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O'Connor TP. Developing Multiple Lines of Evidence to Decrease Drainage-to-Surface Area Ratio for Effective Stormwater Control Sizing Using Bioretention. J Sustain Water Built Environ 2023; 9:1-12. [PMID: 37701074 PMCID: PMC10494893 DOI: 10.1061/jswbay.0001005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 07/24/2022] [Indexed: 09/14/2023]
Abstract
Bioretention units were constructed at the US Environmental Protection Agency's Edison Environmental Center to evaluate drainage-to-surface runoff ratio for sizing of bioretention stormwater controls. Three sizes of hydraulically isolated bioretention units were tested in duplicate with changes in aspect ratio of length from inlet wall by doubling successive length from smallest (3.7 m) to largest (14.9 m) while width remained the same (7.1 m). The watershed areas were nominally the same, resulting in watershed-to-surface area ratios of 5.5:1 for largest duplicate units, 11:1 for the middle units, and 22:1 for the smallest. Each unit was instrumented for continuous monitoring with water content reflectometers (WCRs) and thermistors with data collected since November 2009. The bioretention units were filled with planting media initially comprising 90% sand and 10% sphagnum peat moss by volume and approximately 99% and 1%, respectively, by weight. These units were then planted between May and November of 2010 with a variety of native grasses, perennials, shrubs, and trees that were tolerant to inundation, drought and salt. In late 2012, a survey of the shrubs planted in these bioretention units was performed. The published results of the combined analyses of moisture content, rainfall, and size of shrubs indicated that the smaller units had superior shrub growth due to the more frequent saturation of the root zone as measured by WCR, while the plants in the largest units, particularly away from front wall where runoff entered, potentially relied on direct rainfall only. Starting in 2017, additional monitoring was performed in these units, including chemistry analysis by loss on ignition and total phosphorus of the engineered planting media and an additional survey of the plants. As in the previous study, plants did better in the medium (11:1) and small (22:1) bioretention units than in the largest units (5.5:1), and there was greater buildup of organic matter and phosphorus in the smaller units. One species of grass that dominated the two largest bioretention units away from the inlet was drought tolerant, which indicated that plants in these units relied on rainfall rather than stormwater runoff. Oversized units did not completely use the stromwater control volume, and many of the other original plantings grew slower or were less widespread in comparison to plantings in that smaller units that flooded more frequently and achieved greater growth. Practical Applications Defining the size of stormwater controls can be difficult because there are often multiple objectives imposed on the final design of these structures, including safety and flooding. Results presented here would indicate that if the objective is to create a bioretention area with healthy vegetation, undersized controls may be acceptable because undersized infiltrating controls will have healthier plantings and infiltrate throughout the storm. For municipalities, this means that rights of way previously thought to be too small to use for infiltrative stormwater controls may be converted to such a purpose. This does not free municipalities from stormwater systems that address flooding and safety design objectives, but demonstrates that increasing plantings in the municipal right of way could help to address stormwater as well as other objectives, like greenhouse gas emissions, urban heat island reduction, and clean air. Distributed bioretention controls that capture part or all the runoff of the smaller, most frequent rainfall events should be incorporated throughout municipalities and into their overall stormwater control systems. If clogging by runoff is a concern, roof runoff may be more appropriate for bioretention, or other measures such as sediment capture or increased maintenance may need to be performed.
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Affiliation(s)
- Thomas P O'Connor
- Environmental Engineer, United States Environmental Protection Agency, Stormwater Management Branch, 2890 Woodbridge Ave. (MS-104), Edison, NJ 08817
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2
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O'Connor TP, Borst M. Predicting location and evaluating progression of clogging in a permeable pavement parking lot. J Green Build 2022; 17:3-18. [PMID: 36798811 PMCID: PMC9926402 DOI: 10.3992/jgb.17.4.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
In 2009, a permeable pavement research and demonstration site was constructed at the Edison Environmental Center, Edison, NJ. Infiltration testing of three original permeable parking rows through August 2012 indicated that clogging occurred along the upgradient edge of these pavements from runoff that drained from adjacent impermeable driving lanes. A subsequent infiltration testing data collection effort from April 2017 through March 2020 focused on permeable interlocking concrete pavers (PICP) that replaces one of the original permeable surfaces. While the original infiltration study through 2012 used random locations throughout the permeable parking rows, the newer study targeted upgradient edge to identify where clogging would occur. Testing locations along the upgradient edge were selected based on a high-resolution survey (HRS) of the parking lot performed in December 2014. The HRS identified three low spots along the upgradient edge that eventually clogged in the new PICP infiltration study. The HRS may assist with maintenance routines. The newer study also supports the conclusion of the earlier study with regards to truncating the infiltration testing method, particularly for maintenance assessments.
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Affiliation(s)
- Thomas P O'Connor
- Environmental Engineer, U.S. EPA Office of Research and Development, Edison, New Jersey, 2890 Woodbridge Ave. MS 104, Edison, NJ 08837-3679
| | - Michael Borst
- Chemical Engineer, U.S. EPA Office of Research and Development, Edison, New Jersey, 2890 Woodbridge Ave. MS 104, Edison, NJ 08837-3679
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Müller P, Bagdasarova Y, Hong R, Leredde A, Bailey KG, Fléchard X, García A, Graner B, Knecht A, Naviliat-Cuncic O, O'Connor TP, Sternberg MG, Storm DW, Swanson HE, Wauters F, Zumwalt DW. β-Nuclear-Recoil Correlation from ^{6}He Decay in a Laser Trap. Phys Rev Lett 2022; 129:182502. [PMID: 36374704 DOI: 10.1103/physrevlett.129.182502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 05/12/2022] [Accepted: 06/01/2022] [Indexed: 06/16/2023]
Abstract
We report the first precise measurement of a β-recoil correlation from a radioactive noble gas (^{6}He) confined via a magneto-optical trap. The measurement is motivated by the search for exotic tensor-type contributions to the charged weak current. Interpreted as tensor currents with right-handed neutrinos, the measurements yield |C_{T}/C_{A}|^{2}≤0.022 (90% confidence limit, C.L.). On the other hand, for left-handed neutrinos the limits are 0.007<C_{T}/C_{A}<0.111 (90% C.L.). The sensitivity of the present measurement is mainly limited by experimental uncertainties in determining the time response properties and the distance between the atom cloud and the microchannel plate used for recoil ion detection.
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Affiliation(s)
- P Müller
- Physics Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Y Bagdasarova
- Center for Experimental Nuclear Physics and Astrophysics, University of Washington, Seattle, Washington 98105, USA
| | - R Hong
- Center for Experimental Nuclear Physics and Astrophysics, University of Washington, Seattle, Washington 98105, USA
| | - A Leredde
- Physics Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - K G Bailey
- Physics Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - X Fléchard
- Normandie Univ, ENSICAEN, UNICAEN, CNRS/IN2P3, LPC Caen, 14000 Caen, France
| | - A García
- Center for Experimental Nuclear Physics and Astrophysics, University of Washington, Seattle, Washington 98105, USA
| | - B Graner
- Center for Experimental Nuclear Physics and Astrophysics, University of Washington, Seattle, Washington 98105, USA
| | - A Knecht
- Center for Experimental Nuclear Physics and Astrophysics, University of Washington, Seattle, Washington 98105, USA
- Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - O Naviliat-Cuncic
- Normandie Univ, ENSICAEN, UNICAEN, CNRS/IN2P3, LPC Caen, 14000 Caen, France
- National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - T P O'Connor
- Physics Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - M G Sternberg
- Center for Experimental Nuclear Physics and Astrophysics, University of Washington, Seattle, Washington 98105, USA
| | - D W Storm
- Center for Experimental Nuclear Physics and Astrophysics, University of Washington, Seattle, Washington 98105, USA
| | - H E Swanson
- Center for Experimental Nuclear Physics and Astrophysics, University of Washington, Seattle, Washington 98105, USA
| | - F Wauters
- Center for Experimental Nuclear Physics and Astrophysics, University of Washington, Seattle, Washington 98105, USA
- Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, 55128 Mainz, Germany
| | - D W Zumwalt
- Center for Experimental Nuclear Physics and Astrophysics, University of Washington, Seattle, Washington 98105, USA
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Selvakumar A, O'Connor TP. Seasonal variation in indicator organisms infiltrating from permeable pavement parking lots at the Edison Environmental Center, New Jersey. Water Environ Res 2022; 94:e10791. [PMID: 36124435 PMCID: PMC9620484 DOI: 10.1002/wer.10791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 08/25/2022] [Accepted: 08/29/2022] [Indexed: 06/15/2023]
Abstract
Four types of permeable pavements were monitored at the Edison Environmental Center in Edison, New Jersey, for three water quality indicator organisms consisting of fecal coliform, enterococci, and Escherichia coli. This study expands a previously published result based on less than a year of available data. The current study reflects nearly 5 years of data collection with efforts focusing on collection of data in all four seasons to analyze seasonal effects and to understand the effects of pH on infiltrate concentrations. All three indicators were detected in infiltrates from all four permeable surfaces and as well as asphalt and roof runoff. Seasonally, the infiltrate during winter had fewer detections and lower enumerations and was most often significantly different than surface infiltrate and runoff for the other seasons. More significant concentration reductions were observed in summer and fall, and the lowest reduction was observed in winter. Pervious Asphalt treatment removed the most microorganisms for all three indicator organisms. A permeable interlocking concrete pavement (PICP) that was a replacement for pervious concrete during the study performed better than the original PICP most likely due to smaller gap spacing (8 mm compared to 12.7 mm) and correspondingly smaller specified surface aggregate compared to the original PICP. Percent concentration removal reductions based on geometric means were 89% or greater for PC, PA, and PICP for fecal coliform; 75% or better for PC, PA and PICP for E. coli; and 95% or greater for PC and PA for enterococci, while there were no annual removals for enterococci for original or new PICP nor removals for E. coli for original PICP and minimal removal for fecal coliform for original PICP. The major sources of fecal indicators in the stormwater runoff were most likely from the feces of deer, geese, and other wild animals. PRACTITIONER POINTS: The infiltrate during winter had fewer detections and lower enumerations and was most often significantly different than surface infiltrate and runoff for the other seasons. More significant concentration reductions were observed in summer and fall, and the lowest reduction was observed in winter. Pervious Asphalt treatment removed the most microorganisms for all three indicator organisms.
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Affiliation(s)
- Ariamalar Selvakumar
- Center for Environmental Solutions and Emergency Response, Office of Research and Development, United States Environmental Protection Agency, Edison, New Jersey, USA
| | - Thomas P O'Connor
- Center for Environmental Solutions and Emergency Response, Office of Research and Development, United States Environmental Protection Agency, Edison, New Jersey, USA
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Shevade AV, O'Callaghan YC, O'Brien NM, O'Connor TP, Guinee TP. Development of a dehydrated fortified food base from fermented milk and parboiled wheat, and comparison of its composition and reconstitution behavior with those of commercial dried dairy-cereal blends. Food Sci Nutr 2019; 7:3681-3691. [PMID: 31763017 PMCID: PMC6848806 DOI: 10.1002/fsn3.1226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 09/03/2019] [Accepted: 09/14/2019] [Indexed: 11/08/2022] Open
Abstract
Dehydrated blends of milk and cereal are reconstituted and consumed as a nutritious soup or porridge in many regions; the composition and reconstitution behavior of the blends are likely to impact on nutritional quality and consumer acceptability of the soup/porridge. Experimental samples of dried fermented milk-bulgur wheat blend (FMBW) and commercial samples of dried dairy-cereal blends, namely kishk, tarhana, and super cereal plus corn-soy blend (SCpCSB) were compared for composition, color, water sorption, and reconstitution characteristics. FMBW blends had higher contents of protein, Ca, lactose and lactic acid, lower levels of salt (NaCl) and Fe, and a lighter, more-yellow color (higher L* and b*-color co-ordinates) than tarhana or kishk. Compared with SCpCSB, FMBW had numerically higher levels of protein, lactose, and lactic acid, lower levels of Ca, Fe, Zn, and Mg, and lower pH. Tarhana had highest mean levels of starch, and on reconstitution (133 g/kg) had highest water holding capacity, viscosity during pasting and cooling, yield stress (σ 0), consistency coefficient (K), and viscosity on shearing from 20 to 120 s-1 at 60°C. Reconstituted FMBW, kishk, and SCpCSB had similar pasting and flow behavior properties. Overall, the composition (starch, protein, Ca, Mg), pasting and flow behavior characteristics of FMBW were closer to those SCpCSB and kishk than to tarhana. The results suggest that the FMBW powder, on appropriate supplementation with Ca, Fe, Zn and Mg, could be used for the development of customized fortified blended foods for specific groups.
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Affiliation(s)
- Ashwini V. Shevade
- Teagasc Food Research Centre MooreparkFermoyIreland
- School of Food and Nutritional SciencesUniversity College CorkCorkIreland
| | | | - Nora M. O'Brien
- School of Food and Nutritional SciencesUniversity College CorkCorkIreland
| | - Thomas P. O'Connor
- School of Food and Nutritional SciencesUniversity College CorkCorkIreland
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Stillman BA, Thatcher B, Beall MJ, Lappin M, O'Connor TP, Chandrashekar R. Borrelia burgdorferi Antibody Test Results in Dogs Administered 4 Different Vaccines. Top Companion Anim Med 2019; 37:100358. [PMID: 31837754 DOI: 10.1016/j.tcam.2019.100358] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 08/01/2019] [Accepted: 09/04/2019] [Indexed: 11/30/2022]
Abstract
Vaccines against Borrelia burgdorferi are administered frequently to dogs in areas endemic for the infection. These vaccines produce an antibody response to spirochetal proteins that cross-react in many antibody tests, including immunofluorescence assay, Western blot, and whole cell ELISA used to document exposure to B. burgdorferi. The purpose of this study was to determine whether the in-clinic C6 ELISA assay (SNAP® 4Dx® Plus; IDEXX Laboratories, Inc., Westbrook, Maine) and the quantitative format C6 ELISA (Lyme Quant C6® Antibody Test, IDEXX Laboratories, Inc., Westbrook, ME) react to sera from dogs that have been vaccinated with 1 of 4 different commercially available B. burgdorferi vaccines. Four groups of 3 dogs each were each administered one of the 4 vaccines and sera evaluated over time by indirect fluorescent antibody assay, western blot immunoassay, the in-clinic C6 ELISA assay, and the quantitative format C6 ELISA. While all dogs developed B. burgdorferi antibodies detectable by indirect fluorescent antibody assay and western blot immunoassay after vaccination, none of the samples were positive in either of the C6 peptide-based assays. Based on these results, positive anti-C6 antibody results in client-owned dogs are likely to reflect exposure to B. burgdorferi rather than vaccination.
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Affiliation(s)
- Brett A Stillman
- Infectious Diseases R&D, IDEXX Laboratories, Inc., Westbrook ME, USA
| | - Brendon Thatcher
- Infectious Diseases R&D, IDEXX Laboratories, Inc., Westbrook ME, USA
| | - Melissa J Beall
- Infectious Diseases R&D, IDEXX Laboratories, Inc., Westbrook ME, USA
| | - Michael Lappin
- Department of Clinical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Thomas P O'Connor
- Infectious Diseases R&D, IDEXX Laboratories, Inc., Westbrook ME, USA
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7
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Liu J, Eberts M, Bewsey H, O'Connor TP, Chandrashekar R, Breitschwerdt EB. Sensitivity and specificity levels of two rapid assays for antibodies to Anaplasma spp. in dogs. J Vet Diagn Invest 2017; 30:290-293. [PMID: 29202672 DOI: 10.1177/1040638717745932] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Canine anaplasmosis is a tick-borne disease of dogs that results following infection with Anaplasma phagocytophilum or Anaplasma platys. The SNAP 4Dx Plus test (IDEXX Laboratories) and the VetScan Canine Anaplasma Rapid test (Abaxis) are commercial in-house rapid tests for the detection of antibody to these 2 antigenically related Anaplasma species. We evaluated 2 tests using serum and whole blood samples obtained from reference laboratories and veterinary hospitals. Samples were obtained from regions of the country known to be habitats of the primary tick vectors. The A. phagocytophilum sample set comprised 236 dog sera from the northeastern and midwestern United States; the A. platys sample set comprised 179 sera from dogs living in the southwestern United States. An indirect immunofluorescent antibody (IFA) test and an A. platys species-specific ELISA were used as reference assays for the A. phagocytophilum and A. platys samples, respectively. The SNAP test demonstrated significantly higher sensitivity (84.7% for A. phagocytophilum and 83.1% for A. platys), compared to the VetScan test (39.0% for A. phagocytophilum and 57.6% for A. platys). The specificity of the SNAP test (95.8% for A. phagocytophilum and 99.2% for A. platys) was significantly greater than the VetScan test (85.6% for A. phagocytophilum and 82.5% for A. platys). In a separate clinic study, conducted within an A. phagocytophilum-endemic state (Minnesota) using 154 whole blood samples from client-owned dogs, the VetScan test was negative for 22 of 39 SNAP and IFA seropositive samples.
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Affiliation(s)
- Jiayou Liu
- Department of Assay R&D, IDEXX Laboratories Inc., Westbrook, ME (Liu, Bewsey, O'Connor, Chandrashekar).,Lakeland Veterinary Hospital, N. Baxter, MN (Eberts).,Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC (Breitschwerdt)
| | - Matthew Eberts
- Department of Assay R&D, IDEXX Laboratories Inc., Westbrook, ME (Liu, Bewsey, O'Connor, Chandrashekar).,Lakeland Veterinary Hospital, N. Baxter, MN (Eberts).,Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC (Breitschwerdt)
| | - Hannah Bewsey
- Department of Assay R&D, IDEXX Laboratories Inc., Westbrook, ME (Liu, Bewsey, O'Connor, Chandrashekar).,Lakeland Veterinary Hospital, N. Baxter, MN (Eberts).,Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC (Breitschwerdt)
| | - Thomas P O'Connor
- Department of Assay R&D, IDEXX Laboratories Inc., Westbrook, ME (Liu, Bewsey, O'Connor, Chandrashekar).,Lakeland Veterinary Hospital, N. Baxter, MN (Eberts).,Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC (Breitschwerdt)
| | - Ramaswamy Chandrashekar
- Department of Assay R&D, IDEXX Laboratories Inc., Westbrook, ME (Liu, Bewsey, O'Connor, Chandrashekar).,Lakeland Veterinary Hospital, N. Baxter, MN (Eberts).,Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC (Breitschwerdt)
| | - Edward B Breitschwerdt
- Department of Assay R&D, IDEXX Laboratories Inc., Westbrook, ME (Liu, Bewsey, O'Connor, Chandrashekar).,Lakeland Veterinary Hospital, N. Baxter, MN (Eberts).,Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC (Breitschwerdt)
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O'Connor TP. Detection of Semivolatile Organic Compounds in Permeable Pavement Infiltrate. J Sustain Water Built Environ 2017; 3:999. [PMID: 30345369 PMCID: PMC6192423 DOI: 10.1061/jswbay.0000822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 11/11/2016] [Indexed: 06/08/2023]
Abstract
The U.S. Environmental Protection Agency's Edison Environmental Center (EEC) has a research and demonstration permeable parking lot comprised of three different permeable systems: permeable asphalt, pervious concrete, and permeable interlocking concrete pavers. Water quality and quantity analysis has been ongoing since January 2010. This paper describes analysis of semivolatile organic compounds (SVOCs) to determine if hydrocarbons were in water that infiltrated through the permeable surfaces. SVOCs were analyzed in samples collected from 11 dates over a 3-year period, from February 8, 2010 to April 1, 2013. Results are broadly divided into three categories: 42 chemicals were never detected; 12 chemicals (11 chemical test) were detected at a rate of less than 10% or less; and 22 chemicals were detected at a frequency of 10% or greater (ranging from 10 to 66.5% detections). Fundamental and exploratory statistical analyses were performed on the 22 most observed chemicals. The statistical analyses were limited due to low frequency of detections and dilutions of samples, which impacted detection limits. The infiltrate data through three permeable surfaces were analyzed as nonparametric data by the Kaplan-Meier estimation method for fundamental statistics; there were some statistically observable differences in median concentration between pavement types when using Tarone-Ware comparison hypothesis test. A result was that three groups could be identified based on whether observed porous asphalt infiltrate concentration were greater than, similar to, or less than permeable interlocking concrete pavers infiltrate concentration. Identifying these three groups allowed one-way analysis on chemical attributes; the octonal water partitioning (logK OW), number of benzene rings, and molecular complexity were all significant. These 22 most observed chemicals in the infiltrate were further tested by Spearman rank order nonparametric for correlations between frequency of detection and chemical attributes; significant correlations were observed for porous asphalt frequency of detection and molecular weight (MW), Henry's constant, log K OW and molecular complexity, while both permeable concretes did not have any significant correlations between frequency of detection and chemical parameters. Conclusions from the statistical analyses on the 22 most frequently observed SVOCs in the infiltrate indicate that porous asphalt acts as a source for chemicals with low log K OW and MW and a sink for chemicals with high log K OW and MW, while no significant pattern was observed in the SVOC infiltrate concentrations of the two types of concrete.
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Affiliation(s)
- Thomas P O'Connor
- Environmental Engineer, Urban Watershed Management Branch, U.S. Environmental Protection Agency, 2890 Woodbridge Ave. (MS-104), Edison, NJ 08817.
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Dietrich MR, Bailey KG, O'Connor TP. Alignment of a vector magnetometer to an optical prism. Rev Sci Instrum 2017; 88:055105. [PMID: 28571399 DOI: 10.1063/1.4983146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A method for alignment of a vector magnetometer to a rigidly attached prism is presented. This enables optical comparison of the magnetometer axes to physical surfaces in the apparatus, and thus an absolute determination of the magnetic field direction in space. This is in contrast with more common techniques, which focus on precise determination of the relative angles between magnetometer axes, and so are more suited to measuring differences in the direction of magnetic fields. Here we demonstrate precision better than 500 μrad on a fluxgate magnetometer, which also gives the coil orthogonality errors to a similar precision. The relative sensitivity of the three axes is also determined, with a precision of about 5 × 10-4.
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Affiliation(s)
- M R Dietrich
- Physics Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - K G Bailey
- Physics Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - T P O'Connor
- Physics Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
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Carmichael RC, Duell JR, Holbrook TC, Herrin BH, Leutenegger CM, O'Connor TP, Little SE. Antibodies Reactive toEhrlichiaspp. Are Common in Oklahoma Horses. Vector Borne Zoonotic Dis 2014; 14:552-6. [DOI: 10.1089/vbz.2013.1570] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Robert C. Carmichael
- Department of Veterinary Clinical Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, Oklahoma
| | - Jason R. Duell
- Department of Veterinary Clinical Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, Oklahoma
| | - Todd C. Holbrook
- Department of Veterinary Clinical Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, Oklahoma
| | - Brian H. Herrin
- Department of Veterinary Clinical Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, Oklahoma
| | | | | | - Susan E. Little
- Department of Veterinary Clinical Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, Oklahoma
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11
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Xu CY, Singh J, Zappala JC, Bailey KG, Dietrich MR, Greene JP, Jiang W, Lemke ND, Lu ZT, Mueller P, O'Connor TP. Measurement of the hyperfine quenching rate of the clock transition in 171YB. Phys Rev Lett 2014; 113:033003. [PMID: 25083643 DOI: 10.1103/physrevlett.113.033003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Indexed: 06/03/2023]
Abstract
We report the first experimental determination of the hyperfine quenching rate of the 6s(2) (1)S(0)(F = 1/2) - 6s6p (3)P(0)(F = 1/2) transition in (171)Yb with nuclear spin I = 1/2. This rate determines the natural linewidth and the Rabi frequency of the clock transition of a Yb optical frequency standard. Our technique involves spectrally resolved fluorescence decay measurements of the lowest lying (3)P(0,1) levels of neutral Yb atoms embedded in a solid Ne matrix. The solid Ne provides a simple way to trap a large number of atoms as well as an efficient mechanism for populating (3)P(0). The decay rates in solid Ne are modified by medium effects including the index-of-refraction dependence. We find the (3)P(0) hyperfine quenching rate to be (4.42 ± 0.35) × 10(-2) s(-1) for free (171)Yb, which agrees with recent ab initio calculations.
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Affiliation(s)
- C-Y Xu
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA and Department of Physics and Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637, USA
| | - J Singh
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - J C Zappala
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA and Department of Physics and Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637, USA
| | - K G Bailey
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - M R Dietrich
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - J P Greene
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - W Jiang
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - N D Lemke
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - Z-T Lu
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA and Department of Physics and Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637, USA
| | - P Mueller
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - T P O'Connor
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
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Zappala JC, Bailey K, Lu ZT, O'Connor TP, Jiang W. Note: efficient generation of optical sidebands at GHz with a high-power tapered amplifier. Rev Sci Instrum 2014; 85:046104. [PMID: 24784682 DOI: 10.1063/1.4870412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Two methods using a laser-diode tapered amplifier to produce high-power, high-efficiency optical frequency sidebands over a wide tunable frequency range are studied and compared. For a total output of 500 mW at 811 nm, 20% of the power can be placed in each of the first-order sidebands. Functionality and characterization are presented within the sideband frequency region of 0.8-2.3 GHz, and it is shown that both methods can be applied beyond this frequency range. These methods provide a versatile and effective tool for atomic physics experiments.
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Affiliation(s)
- J C Zappala
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - K Bailey
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - Z-T Lu
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - T P O'Connor
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - W Jiang
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
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13
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Jiang W, Bailey K, Lu ZT, Mueller P, O'Connor TP, Purtschert R. Ion current as a precise measure of the loading rate of a magneto-optical trap. Opt Lett 2014; 39:409-412. [PMID: 24562159 DOI: 10.1364/ol.39.000409] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We have demonstrated that the ion current resulting from collisions between metastable krypton atoms in a magneto-optical trap can be used to precisely measure the trap loading rate. We measured both the ion current of the abundant isotope 83Kr (isotopic abundance=11%) and the single-atom counting rate of the rare isotope 85Kr (isotopic abundance∼1×10(-11)), and found the two quantities to be proportional at a precision level of 0.9%. This work results in a significant improvement in using the magneto-optical trap as an analytical tool for noble-gas isotope ratio measurements, and will benefit both atomic physics studies and applications in the earth sciences.
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O'Connor TP, Muthukrishnan S, Barshatzky K, Wallace W. Trace metal accumulation in sediments and benthic macroinvertebrates before and after maintenance of a constructed wetland. Water Environ Res 2012; 84:370-381. [PMID: 22834226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Stormwater best management practices (BMPs) require regular maintenance. The impact on trace metal concentrations in a constructed stormwater wetland BMP on Staten Island, New York, was investigated by analyzing sediment concentrations and tissue residues of the dominant macroinvertebrates (Tubifex tubifex) prior and subsequent to maintenance. Trace metal concentrations were assessed using standard serial extraction (for sediment) and acid digestion (for tissue burdens) techniques, followed by quantitative determination using graphite furnace atomic absorption spectrometry and inductively coupled plasma optical emission spectrometry, respectively. The results suggest that disturbance of sediment during maintenance of the BMP resulted in an increase in the most mobile fraction of trace metals, especially those associated with finer grained sediments (< 63 tm), and as a consequence, measured metal concentrations in macroinvertebrates increased. Regressions of a subset of metal concentrations (copper, lead, and zinc) in sediment and the macroinvertebrate tissue burden samples generally increased as a result of maintenance. A follow-up sampling event 9 months after maintenance demonstrated that the most readily available form of trace metal in the BMP was reduced, which supports (1) long-term sequestration of metals in the BMP and (2) that elevated bioavailability following maintenance was potentially a transient feature of the disturbance. This study suggests that in the long-term, performing sediment removal might help reduce bioavailability of trace metal concentrations in both the BMP and the receiving water to which a BMP discharges. However, alternative practices might need to be implemented to reduce trace metal bioavailability in the short-term.
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Affiliation(s)
- Thomas P O'Connor
- U.S. Environmental Protection Agency, National Risk Management Research Laboratory, Urban Watershed Management Branch, 2890 Woodbridge Avenue, Edison, NJ 08817, USA.
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15
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Xu CY, Hu SM, Singh J, Bailey K, Lu ZT, Mueller P, O'Connor TP, Welp U. Optical excitation and decay dynamics of ytterbium atoms embedded in a solid neon matrix. Phys Rev Lett 2011; 107:093001. [PMID: 21929234 DOI: 10.1103/physrevlett.107.093001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Indexed: 05/31/2023]
Abstract
Neutral ytterbium atoms embedded in solid neon qualitatively retain the structure of free atoms. Despite the atom-solid interaction, the 6s6p ³P(0) level is found to remain metastable with its lifetimes determined to be in the range of ten to hundreds of seconds. The atomic population can be almost completely transferred between the ground level and the metastable level via optical excitation and spontaneous decay. The dynamics of this process is examined and is used to explicitly demonstrate that the transition broadening mechanism is homogeneous.
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Affiliation(s)
- C-Y Xu
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
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16
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Jiang W, Williams W, Bailey K, Davis AM, Hu SM, Lu ZT, O'Connor TP, Purtschert R, Sturchio NC, Sun YR, Mueller P. 39Ar detection at the 10(-16) isotopic abundance level with atom trap trace analysis. Phys Rev Lett 2011; 106:103001. [PMID: 21469788 DOI: 10.1103/physrevlett.106.103001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Indexed: 05/30/2023]
Abstract
Atom trap trace analysis, a laser-based atom counting method, has been applied to analyze atmospheric 39Ar (half-life=269 yr), a cosmogenic isotope with an isotopic abundance of 8×10(-16). In addition to the superior selectivity demonstrated in this work, the counting rate and efficiency of atom trap trace analysis have been improved by 2 orders of magnitude over prior results. The significant applications of this new analytical capability lie in radioisotope dating of ice and water samples and in the development of dark matter detectors.
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Affiliation(s)
- W Jiang
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
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17
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Yabsley MJ, Adams DS, O'Connor TP, Chandrashekar R, Little SE. Experimental primary and secondary infections of domestic dogs with Ehrlichia ewingii. Vet Microbiol 2011; 150:315-21. [PMID: 21397411 DOI: 10.1016/j.vetmic.2011.02.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Revised: 02/04/2011] [Accepted: 02/10/2011] [Indexed: 11/27/2022]
Abstract
In this study, the infection dynamics of Ehrlichia ewingii, causative agent of granulocytotropic ehrlichiosis in dogs and humans, was examined in experimentally infected dogs by using a combination of physical examination, hematologic and biochemical analyses, and molecular and serologic assays. For the experimental trials, blood from an E. ewingii-infected dog was inoculated intravenously into two naïve dogs and two dogs with prior experimental exposure to E. ewingii (both were negative for E. ewingii DNA by polymerase chain reaction (PCR) assay, but seropositive from initial infection 8 and 10 months prior to challenge). A negative control dog was inoculated with blood from a negative dog. The two primary infection dogs were positive for E. ewingii DNA on DPI 4, remained consistently positive until DPI 60, and were intermittently positive until the end of the study (DPI 144). The two primary infection dogs developed antibodies reactive to E. ewingii by DPI 28 and remained seropositive for the duration of the study. Primary infected dogs had intermittent fever, thrombocytopenia, and leukopenia and some dogs were hyperphosphatemic and/or had elevated ALP levels. The two challenge dogs were positive for E. ewingii DNA on DPI 4 and 18, which was similar to the primary infection dogs, but the duration of E. ewingii DNA detection was shorter. Also, the two challenged dogs did not develop pyrexia or show any hematologic or biochemical abnormalities. E. ewingii was successfully transmitted between dogs by Amblyomma americanum, but not Rhipicephalus sanguineus. This study provides data on the infection dynamics of E. ewingii in dogs during primary and challenge infections and suggests that prior exposure may lessen clinical disease during subsequent infections.
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Affiliation(s)
- Michael J Yabsley
- D.B. Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA.
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18
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O'Connor TP, Saucier JM, Daniluk D, Stillman BA, Krah R, Rikihisa Y, Xiong Q, Yabsley MJ, Adams DS, Diniz PPVP, Breitschwerdt EB, Gaunt SD, Chandrashekar R. Evaluation of peptide- and recombinant protein-based assays for detection of anti-Ehrlichia ewingii antibodies in experimentally and naturally infected dogs. [corrected]. Am J Vet Res 2010; 71:1195-200. [PMID: 20919906 DOI: 10.2460/ajvr.71.10.1195] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate microtiter-plate format ELISAs constructed by use of different diagnostic targets derived from the Ehrlichia ewingii p28 outer membrane protein for detection of E ewingii antibodies in experimentally and naturally infected dogs. SAMPLE POPULATION Serum samples from 87 kenneled dogs, 9 dogs experimentally infected with anti-E ewingii, and 180 potentially naturally exposed dogs from Missouri. PROCEDURES The capacities of the synthetic peptide and truncated recombinant protein to function as detection reagents in ELISAs were compared by use of PCR assay, western blot analysis, and a full-length recombinant protein ELISA. Diagnostic targets included an E ewingii synthetic peptide (EESP) and 2 recombinant proteins: a full-length E ewingii outer membrane protein (EEp28) and a truncated E ewingii outer membrane protein (EETp28) RESULTS A subset of Ehrlichia canis-positive samples cross-reacted in the EEp28 ELISA; none were reactive in the EESP and EETp28 ELISAs. The EESP- and EETp28-based ELISAs detected E ewingii seroconversion at approximately the same time after infection as the EEp28 ELISAs. In afield population, each of the ELISAs identified the same 35 samples as reactive and 27 samples as nonreactive. Anaplasma and E can is peptides used in a commercially available ELISA platform did not detect anti-E ewingii antibodies in experimentally infected dogs. CONCLUSIONS AND CLINICAL RELEVANCE The EESP and EETp28 ELISAs were suitable for specifically detecting anti-E ewingii antibodies in experimentally and naturally infected dogs.
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Affiliation(s)
- Thomas P O'Connor
- Department of Immunoassay R&D, IDEXX Laboratories Incorporated, 1 Indexx Dr, Westbrook, ME 04092, USA.
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19
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Little SE, O'Connor TP, Hempstead J, Saucier J, Reichard MV, Meinkoth K, Meinkoth JH, Andrews B, Ullom S, Ewing SA, Chandrashekar R. Ehrlichia ewingii infection and exposure rates in dogs from the southcentral United States. Vet Parasitol 2010; 172:355-60. [PMID: 20541322 DOI: 10.1016/j.vetpar.2010.05.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2010] [Revised: 04/06/2010] [Accepted: 05/05/2010] [Indexed: 11/26/2022]
Abstract
We used PCR and a novel serologic assay to determine infection and exposure rates to Ehrlichia ewingii in dogs from an area of northeast Oklahoma and northwest Arkansas where Amblyomma americanum ticks are abundant. Of 143 dogs assayed, 13 (9.1%) harbored E. ewingii by PCR and 64 (44.8%) had antibodies to E. ewingii detected using a peptide-based microtiter plate ELISA. Dogs were more likely (P=0.001) to be positive by PCR if sampled in August (30.8%) but no association was found between seropositive status and month of collection of sample (P>0.05). Additional testing revealed PCR evidence of Ehrlichia chaffeensis (4/143; 2.8%) and Anaplasma platys (5/143; 3.5%) as well as antibodies reactive to E. chaffeensis (25/143; 17.5%), Ehrlichia canis (2/143; 1.4%), and Anaplasma spp. (8/143; 5.6%). Testing of another 200 dogs from the area revealed additional PCR and/or serologic evidence of E. ewingii, E. canis, E. chaffeensis, and A. platys. None of the 343 dogs evaluated had evidence of Borrelia burgdorferi exposure. These data support the interpretation that E. ewingii may be the primary agent of canine ehrlichiosis in this region, and suggest that diagnostic evaluation of dogs suspected to have a tick-borne disease should include assays targeting this organism.
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Affiliation(s)
- Susan E Little
- Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK, USA.
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20
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Murdock JH, Yabsley MJ, Little SE, Chandrashekar R, O'Connor TP, Caudell JN, Huffman JE, Langenberg JA, Hollamby S. Distribution of antibodies reactive to Borrelia lonestari and Borrelia burgdorferi in white-tailed deer (Odocoileus virginianus) populations in the eastern United States. Vector Borne Zoonotic Dis 2010; 9:729-36. [PMID: 19874183 DOI: 10.1089/vbz.2008.0144] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Southern tick-associated rash illness is a Lyme-like syndrome that occurs in the southern states. Borrelia lonestari, which has been suggested as a possible causative agent of southern tick-associated rash illness, naturally infects white-tailed deer (WTD; Odocoileus virginianus) and is transmitted by the lone star tick (Amblyomma americanum). To better understand the prevalence and distribution of Borrelia exposure among WTD, we tested WTD from 21 eastern states for antibodies reactive to B. lonestari using an indirect immunofluorescent antibody assay and Borrelia burgdorferi using the IDEXX SNAP 4Dx test. A total of 107/714 (15%) had antibodies reactive to B. lonestari, and prevalence of antibodies was higher in deer from southern states (17.5%) than in deer from northern states (9.2%). Using the SNAP 4DX test, we found that 73/723 (10%) were positive for B. burgdorferi, and significantly more northern deer (23.9%) were positive compared with southern deer (3.8%). Our data demonstrate that WTD are exposed to both Borrelia species, but antibody prevalence for exposure to the two species differs regionally and distributions correlate with the presence of Ixodes scapularis and A. americanum ticks.
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Affiliation(s)
- Jessica H Murdock
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, Georgia 30602, USA
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21
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Ryan E, Galvin K, O'Connor TP, Maguire AR, O'Brien NM. Fatty acid profile, tocopherol, squalene and phytosterol content of brazil, pecan, pine, pistachio and cashew nuts. Int J Food Sci Nutr 2009; 57:219-28. [PMID: 17127473 DOI: 10.1080/09637480600768077] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Nuts contain bioactive constituents that elicit cardio-protective effects including phytosterols, tocopherols and squalene. The objective of the present study was to determine the total oil content, peroxide value, fatty acid composition and levels of tocopherols, squalene and phytosterols in oil extracted from freshly ground brazil, pecan, pine, pistachio and cashew nuts. The total oil content of the nuts ranged from 40.4 to 60.8% (w/w) while the peroxide values ranged from 0.14 to 0.22 mEq O2/kg oil. The most abundant monounsaturated fatty acid was oleic acid (C18:1), while linoleic acid (C18:2) was the most prevalent polyunsaturated fatty acid. The levels of total tocopherols ranged from 60.8 to 291.0 mg/g. Squalene ranged from 39.5 mg/g oil in the pine nut to 1377.8 mg/g oil in the brazil nut. beta-Sitosterol was the most prevalent phytosterol, ranging in concentration from 1325.4 to 4685.9 mg/g oil. In conclusion, the present data indicate that nuts are a good dietary source of unsaturated fatty acids, tocopherols, squalene and phytosterols.
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Affiliation(s)
- E Ryan
- Department of Food and Nutritional Sciences, University College, Cork, Ireland
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22
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To KCW, Church J, O'Connor TP. Growth cone collapse stimulated by both calpain- and Rho-mediated pathways. Neuroscience 2008; 153:645-53. [PMID: 18407419 DOI: 10.1016/j.neuroscience.2008.02.043] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2007] [Revised: 01/22/2008] [Accepted: 02/14/2008] [Indexed: 10/22/2022]
Abstract
The signal transduction pathways regulating growth cone motility remain poorly defined. Previously, we have characterized the inhibitory molecule, motuporamine C (MotC), as a robust stimulator of growth cone collapse. Utilizing MotC as a research tool to elucidate pathways involved with collapse, we have previously shown that the Rho-Rho kinase (ROCK) pathway is partially required for collapse. In this study, we report MotC induces a high-amplitude rise in intracellular free Ca(2+) concentration levels in chicks, resulting in the activation of the Ca(2+)-sensitive protease, calpain. Furthermore, we show that while calpain is necessary for collapse, inhibition of calpain only partially attenuates MotC-mediated collapse. Instead, concomitant inhibition of both the Rho-ROCK and calpain pathways has an additive effect in attenuating the collapse response to MotC. To our knowledge, this is the first demonstration of concurrent activation of calpain and Rho-ROCK signaling during growth cone collapse. Our data support a model of growth cone collapse that requires the combinatorial regulation of multiple signal transduction cascades that likely target different cellular mechanisms to induce this motile response.
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Affiliation(s)
- K C W To
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, British Columbia, Canada
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23
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Mueller P, Sulai IA, Villari ACC, Alcántara-Núñez JA, Alves-Condé R, Bailey K, Drake GWF, Dubois M, Eléon C, Gaubert G, Holt RJ, Janssens RVF, Lecesne N, Lu ZT, O'Connor TP, Saint-Laurent MG, Thomas JC, Wang LB. Nuclear charge radius of 8He. Phys Rev Lett 2007; 99:252501. [PMID: 18233516 DOI: 10.1103/physrevlett.99.252501] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2007] [Indexed: 05/25/2023]
Abstract
The root-mean-square (rms) nuclear charge radius of 8He, the most neutron-rich of all particle-stable nuclei, has been determined for the first time to be 1.93(3) fm. In addition, the rms charge radius of 6He was measured to be 2.068(11) fm, in excellent agreement with a previous result. The significant reduction in charge radius from 6He to 8He is an indication of the change in the correlations of the excess neutrons and is consistent with the 8He neutron halo structure. The experiment was based on laser spectroscopy of individual helium atoms cooled and confined in a magneto-optical trap. Charge radii were extracted from the measured isotope shifts with the help of precision atomic theory calculations.
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Affiliation(s)
- P Mueller
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
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24
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Ryan E, Galvin K, O'Connor TP, Maguire AR, O'Brien NM. Phytosterol, squalene, tocopherol content and fatty acid profile of selected seeds, grains, and legumes. Plant Foods Hum Nutr 2007; 62:85-91. [PMID: 17594521 DOI: 10.1007/s11130-007-0046-8] [Citation(s) in RCA: 270] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2006] [Accepted: 05/04/2007] [Indexed: 05/10/2023]
Abstract
The unsaponifiable lipid fraction of plant-based foods is a potential source of bioactive components such as phytosterols, squalene, and tocopherols. The objective of the present study was to determine the levels of phytosterols, and squalene, as well as tocopherols (alpha and beta + gamma) in selected grains, seeds, and legumes. The method comprised acid hydrolysis and lipid extraction followed by alkaline saponification, prior to analysis by HPLC. In addition, the fatty acid profile of the foods was determined via total lipid extraction, fatty acid derivitisation and GC analysis. In general, beta-sitosterol was the most prevalent phytosterol, ranging in concentration from 24.9 mg/100 g in pumpkin seed to 191.4 mg/100 g in peas. Squalene identified in all foods examined in this study, was particularly abundant in pumpkin seed (89.0 mg/100 g). The sum of alpha- and beta+ gamma-tocopherols ranged from 0.1 mg/100 g in rye to 15.9 mg/100 g in pumpkin seeds. Total oil content ranged from 0.9% (w/w) in butter beans to 42.3% (w/w) in pumpkin seed and the type of fat, in all foods examined, was predominantly unsaturated. In conclusion, seeds, grains, and legumes are a rich natural source of phytosterols. Additionally, they contain noticeable amounts of squalene and tocopherols, and in general, their fatty acid profile is favorable.
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Affiliation(s)
- E Ryan
- Department of Food and Nutritional Sciences, University College, Cork, Ireland.
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25
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Guest JR, Scielzo ND, Ahmad I, Bailey K, Greene JP, Holt RJ, Lu ZT, O'Connor TP, Potterveld DH. Laser trapping of 225Ra and 226Ra with repumping by room-temperature blackbody radiation. Phys Rev Lett 2007; 98:093001. [PMID: 17359153 DOI: 10.1103/physrevlett.98.093001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2006] [Indexed: 05/14/2023]
Abstract
We have demonstrated Zeeman slowing and capture of neutral 225Ra and 226Ra atoms in a magneto-optical trap. The intercombination transition 1S0-->3P1 is the only quasicycling transition in radium and was used for laser-cooling and trapping. Repumping along the 3D1-->1P1 transition extended the lifetime of the trap from milliseconds to seconds. Room-temperature blackbody radiation was demonstrated to provide repumping from the metastable 3P0 level. We measured the isotope shift and hyperfine splittings on the 3D1-->1P1 transition with the laser-cooled atoms, and set a limit on the lifetime of the 3D1 level based on the measured blackbody repumping rate. Laser-cooled and trapped radium is an attractive system for studying fundamental symmetries.
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Affiliation(s)
- J R Guest
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
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26
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Ding Y, Hu SM, Bailey K, Davis AM, Dunford RW, Lu ZT, O'Connor TP, Young L. Thermal beam of metastable krypton atoms produced by optical excitation. Rev Sci Instrum 2007; 78:023103. [PMID: 17578099 DOI: 10.1063/1.2437193] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
A room-temperature beam of krypton atoms in the metastable 5s[3/2]2 level is demonstrated via an optical excitation method. A Kr-discharge lamp is used to produce vacuum ultraviolet photons at 124 nm for the first-step excitation from the ground level 4p6 1S0 to the 5s[3/2]1 level. An 819 nm Ti:sapphire laser is used for the second-step excitation from 5s[3/2]1 to 5s[3/2]2 followed by a spontaneous decay to the 5s[3/2]2 metastable level. A metastable atomic beam with an angular flux density of 3 x 10(14) s(-1) sr(-1) is achieved at the total gas flow rate of 0.01 cm3/s at STP (or 3 x 10(17) at./s). The dependences of the flux on the gas flow rate, laser power, and lamp parameters are investigated.
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Affiliation(s)
- Y Ding
- Enrico Fermi Institute, The University of Chicago, Chicago, Illinois 60637, USA.
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27
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O'Connor TP, Lauenstein GG. Trends in chemical concentrations in mussels and oysters collected along the US coast: update to 2003. Mar Environ Res 2006; 62:261-85. [PMID: 16777213 DOI: 10.1016/j.marenvres.2006.04.067] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2005] [Revised: 02/17/2006] [Accepted: 04/25/2006] [Indexed: 05/10/2023]
Abstract
With data from the annual analyses of mussels and oysters collected in 1986-1993 from sites located throughout the coastal United States [O'Connor, T.P., 1996. Trends in chemical concentrations in mussels and oysters collected along the US coast from 1986 to 1993. Mar. Environ. Res. 41, 183-200] showed decreasing trends, on a national scale, for chemicals whose use has been banned or has greatly decreased and that concentrations of most other chemicals were neither increasing nor decreasing. With data through 2003 those conclusions still apply. National median concentrations of synthetic organic chemicals and cadmium continue to decrease. The added data show that concentrations of lindane and high molecular weight PAHs are also decreasing on a national scale. For metals other than cadmium and zinc (in mussels), the added data reveal trends at more sites than in 1993 but no additional national trends. However, the longer time series has revealed several local and regional trends.
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Affiliation(s)
- Thomas P O'Connor
- National Oceanic and Atmospheric Administration, National Center for Coastal Ocean Sciences, Center for Coastal Monitoring and Assessment, NOAA N/SCI1, Silver Spring, MD 20910, USA
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28
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O'Connor TP, Hanscom JL, Hegarty BC, Groat RG, Breitschwerdt EB. Comparison of an indirect immunofluorescence assay, western blot analysis, and a commercially available ELISA for detection ofEhrlichia canisantibodies in canine sera. Am J Vet Res 2006; 67:206-10. [PMID: 16454622 DOI: 10.2460/ajvr.67.2.206] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To examine the correlation between results for an indirect immunofluorescence assay (IFA) that uses Ehrlichia canis antigen as a substrate (ie, E canis-IFA), 2 western blot (WB) analyses, and a commercially available ELISA in the detection of E canis antibody in dog sera. SAMPLE POPULATION 54 canine serum samples that were reactive on E canis-IFA and 16 canine serum samples that were E canis-IFA nonreactive. PROCEDURE Serum samples were evaluated by use of 2 WB analyses and a commercially available ELISA. Correlation between results of the 3 testing modalities (ie, IFA, WB analyses, and the ELISA) was examined by use of nonreactive (E canis-IFA reciprocal titer, < 20), low-titer (reciprocal titer, 80 to 160), medium-titer (reciprocal titer, 320 to 2,560), and high-titer (reciprocal titer, 5,120 to > 20,480) serum samples. RESULTS For all serum samples in the nonreactive (n = 16), medium-titer (17), and high-titer (18) groups, correlation of results among IFA, WB analyses, and the commercially available ELISA was excellent. A poor correlation was found between IFA results and those of WB analyses and the ELISA for serum samples in the low-titer group (19), with only 4 of the 19 serum samples having positive results on both WB analyses and the commercially available ELISA. CONCLUSIONS AND CLINICAL RELEVANCE The discrepancy between E canis-IFA, WB analyses, and the commercially available ELISA results for the low-titer serum samples may be related to a high IFA sensitivity or, more likely, a lack of specificity associated with cross-reactivity among Ehrlichia spp.
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Affiliation(s)
- Thomas P O'Connor
- Department of Research and Development, IDEXX Laboratories Inc, 1 IDEXX Dr, Westbrook, ME 04092, USA
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To KCW, Loh KT, Roskelley CD, Andersen RJ, O'Connor TP. The anti-invasive compound motuporamine C is a robust stimulator of neuronal growth cone collapse. Neuroscience 2006; 139:1263-74. [PMID: 16564636 DOI: 10.1016/j.neuroscience.2006.01.065] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2005] [Revised: 01/20/2006] [Accepted: 01/26/2006] [Indexed: 11/21/2022]
Abstract
Neuronal outgrowth is a fundamental process for normal development of the nervous system. Despite recent advances, the molecular mechanisms governing neuronal motility are still poorly understood. To provide insight into the intracellular signaling mechanisms required for neuronal outgrowth, we have characterized the effects of a compound previously identified for its anti-motility effects on transformed cells. We show that this compound, motuporamine C, acts as a robust inhibitor of chick neurite outgrowth in a dose-dependent fashion. Furthermore, in the presence of motuporamine C, growth cone collapse is observed, followed by neurite retraction. After removal, growth cones re-extend lamellipodial and filopodial processes and re-establish motility. Neurons exposed to motuporamine C exhibit a significant upregulation of active Rho-GTP. Additionally, effector-blocking experiments using Rho and Rho-associated kinase inhibitors indicate that the Rho pathway plays a critical role in motuporamine C-mediated growth cone collapse. Thus, we have characterized a novel anti-motility compound that has a robust inhibitory effect on neuronal outgrowth and involves signaling through the Rho-Rho kinase collapse pathway. Due to these robust effects, motuporamine C may serve as a valuable tool in further examining the intracellular mechanisms associated with growth cone motility.
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Affiliation(s)
- K C W To
- Department of Cellular and Physiological Sciences, 2350 Health Sciences Mall, University of British Columbia, Vancouver, Canada.
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Mueller P, Wang LB, Drake GWF, Bailey K, Lu ZT, O'Connor TP. Fine structure of the 1s3p 3PJ level in atomic 4He: theory and experiment. Phys Rev Lett 2005; 94:133001. [PMID: 15903989 DOI: 10.1103/physrevlett.94.133001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2004] [Indexed: 05/02/2023]
Abstract
The fine structure intervals in helium have been the focus of many theoretical and experimental studies in recent years with most of them concentrating on the 1s2p (3)P(J) levels. Here, we report on a theoretical calculation and an experimental determination of the 1s2p (3)P(J) fine structure intervals. The values from the theoretical calculation are 8113.730(6) and 658.801(6) MHz for the nu(01) and nu(12) intervals, respectively. The laser spectroscopic measurement reported here yields 8113.714(28) and 658.810(18) MHz for these intervals and is in excellent agreement with the theoretical calculation. Both, however, disagree significantly with the previous most precise experimental results.
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Affiliation(s)
- P Mueller
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
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O'Connor TP, Esty KJ, Hanscom JL, Shields P, Philipp MT. Dogs vaccinated with common Lyme disease vaccines do not respond to IR6, the conserved immunodominant region of the VlsE surface protein of Borrelia burgdorferi. Clin Diagn Lab Immunol 2005; 11:458-62. [PMID: 15138170 PMCID: PMC404571 DOI: 10.1128/cdli.11.3.458-462.2004] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A 25-amino-acid synthetic peptide (C(6) peptide) derived from an immunodominant conserved region (designated IR(6)) of the VlsE protein of Borrelia burgdorferi has been identified and used to construct immunoenzyme-based diagnostic procedures. These procedures have excellent sensitivity and specificity. Previous reports have demonstrated the usefulness of the C(6) peptide as an antigen for the serodiagnosis of human and canine Lyme disease. Results indicated that assays based on the C(6) peptide were nonreactive to sera from vaccinated nonexposed animals. The purpose of the present study was to confirm these results in a controlled trial by testing sera from experimentally vaccinated dogs known to be uninfected. Nine specific-pathogen-free beagles were assigned to one of three vaccine groups, each containing three dogs. Each group received one of three commercial Lyme vaccines: RECOMBITEK Lyme (Merial), LymeVax (Fort Dodge Animal Health), and Galaxy Lyme (Schering-Plough Animal Health). Each animal was administered a total of five doses of vaccine over a period of 39 weeks. Serum samples were collected prior to vaccination and then on a weekly basis from weeks 3 to 18 and from weeks 33 to 43. Selected samples were tested by the immunofluorescence assay (IFA) and the Western blot (WB) assay using whole-cell B. burgdorferi antigen extracts, and the results were compared to those obtained with two immunoenzyme-based procedures formatted by using the C(6) peptide. Serum specimens from all animals were reactive to the IFA and WB assay at week 5 and became highly reactive following the administration of multiple doses of vaccine. All serum specimens were uniformly nonreactive in the C(6) peptide immunoenzyme procedures at all time points throughout the study.
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Affiliation(s)
- Thomas P O'Connor
- Department of Research and Development, IDEXX Laboratories, One IDEXX Dr., Westbrook, ME 04092, USA.
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Swanson RL, Bortman ML, O'Connor TP, Stanford HM. Science, policy and the management of sewage materials. The New York City experience. Mar Pollut Bull 2004; 49:679-687. [PMID: 15530510 DOI: 10.1016/j.marpolbul.2004.06.025] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Development of national policy on sewage sludge management is a classic example of incremental policy formulation [Fiorino, D.J. 1995. Making Environmental Policy. University of California Press. Berkeley, CA. p. 269]. Consequently, policy has developed piecemeal, and results are, in some ways, different than intended. Land application of sewage sludge has not been a panacea. Many of the same types of policy are now being raised about it. We demonstrate this by examining the management of sewage materials by New York City from near the turn of the 20th century, when ocean dumping was viewed as a means to alleviate some of the gross pollution in New York Harbor, to when ocean dumping was banned, and thence to the present when sludge is applied to land as "biosolids." Lessons learned during this long, sometimes contentious history can be applied to present situations--specifically not understanding the long-term consequences of land-based reuse and disposal technologies.
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Affiliation(s)
- R Lawrence Swanson
- Waste Reduction and Management Institute, Marine Sciences Research Center, Stony Brook University, Stony Brook, NY 11794-5000, USA
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Maguire LS, O'Sullivan SM, Galvin K, O'Connor TP, O'Brien NM. Fatty acid profile, tocopherol, squalene and phytosterol content of walnuts, almonds, peanuts, hazelnuts and the macadamia nut. Int J Food Sci Nutr 2004; 55:171-8. [PMID: 15223592 DOI: 10.1080/09637480410001725175] [Citation(s) in RCA: 293] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Nuts are high in fat but have a fatty acid profile that may be beneficial in relation to risk of coronary heart disease. Nuts also contain other potentially cardioprotective constituents including phytosterols, tocopherols and squalene. In the present study, the total oil content, peroxide value, composition of fatty acids, tocopherols, phytosterols and squalene content were determined in the oil extracted from freshly ground walnuts, almonds, peanuts, hazelnuts and the macadamia nut. The total oil content of the nuts ranged from 37.9 to 59.2%, while the peroxide values ranged from 0.19 to 0.43 meq O2/kg oil. The main monounsaturated fatty acid was oleic acid (C18:1) with substantial levels of palmitoleic acid (C16:1) present in the macadamia nut. The main polyunsaturated fatty acids present were linoleic acid (C18:2) and linolenic acid (C18:3). alpha-Tocopherol was the most prevalent tocopherol except in walnuts. The levels of squalene detected ranged from 9.4 to 186.4 microg/g. beta-Sitosterol was the most abundant sterol, ranging in concentration from 991.2 to 2071.7 microg/g oil. Campesterol and stigmasterol were also present in significant concentrations. Our data indicate that all five nuts are a good source of monounsaturated fatty acid, tocopherols, squalene and phytosterols.
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Affiliation(s)
- L S Maguire
- Department of Food and Nutritional Sciences, University College Cork, Ireland
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34
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Wang LB, Mueller P, Bailey K, Drake GWF, Greene JP, Henderson D, Holt RJ, Janssens RVF, Jiang CL, Lu ZT, O'Connor TP, Pardo RC, Rehm KE, Schiffer JP, Tang XD. Laser spectroscopic determination of the 6He nuclear charge radius. Phys Rev Lett 2004; 93:142501. [PMID: 15524784 DOI: 10.1103/physrevlett.93.142501] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2004] [Indexed: 05/24/2023]
Abstract
We have performed precision laser spectroscopy on individual 6He (t(1/2)=0.8 s) atoms confined and cooled in a magneto-optical trap, and measured the isotope shift between 6He and 4He to be 43 194.772+/-0.056 MHz for the 2(3)S1-3(3)P2 transition. Based on this measurement and atomic theory, the nuclear charge radius of 6He is determined for the first time in a method independent of nuclear models to be 2.054+/-0.014 fm. The result is compared with the values predicted by a number of nuclear structure calculations and tests their ability to characterize this loosely bound halo nucleus.
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Affiliation(s)
- L-B Wang
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
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Abstract
While it is being used as such, the sediment quality guideline ERL (effects range low) is not a threshold of any chemical concentration in sediment at which the probability of toxicity shows an abrupt increase. Similarly, while it has been done, there is no basis for assuming that multiple concentrations above an ERL increase the probability of toxicity.
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Affiliation(s)
- Thomas P O'Connor
- NOAA N/SCI1, Center for Coastal Monitoring and Assessment, 1305 East West Highway, Silver Spring, MD 20910, USA.
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36
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Moore ID, Bailey K, Greene J, Lu ZT, Müller P, O'Connor TP, Geppert C, Wendt KDA, Young L. Counting individual 41Ca atoms with a magneto-optical trap. Phys Rev Lett 2004; 92:153002. [PMID: 15169281 DOI: 10.1103/physrevlett.92.153002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2003] [Indexed: 05/24/2023]
Abstract
Atom trap trace analysis, a novel method based upon laser trapping and cooling, is used to count individual atoms of 41Ca present in biomedical samples with isotopic abundance levels between 10(-8) and 10(-10). The method is calibrated against resonance ionization mass spectrometry, demonstrating good agreement between the two methods. The present system has a counting efficiency of 2x10(-7). Within 1 h of observation time, its 3-sigma detection limit on the isotopic abundance of 41Ca reaches 4.5x10(-10).
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Affiliation(s)
- I D Moore
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
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Mueller P, Wang LB, Holt RJ, Lu ZT, O'Connor TP, Schiffer JP. Search for anomalously heavy isotopes of helium in the earth's atmosphere. Phys Rev Lett 2004; 92:022501. [PMID: 14753932 DOI: 10.1103/physrevlett.92.022501] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2003] [Indexed: 05/24/2023]
Abstract
Our knowledge of the possible existence in nature of stable exotic particles depends solely upon experimental observation. Using a sensitive laser spectroscopy technique, we searched for a doubly charged particle accompanied by two electrons as an anomalously heavy isotope of helium in the Earth's atmosphere. The concentration of noble-gas-like atoms in the atmosphere and the subsequent very large depletion of the light (3,4)He isotopes allow stringent upper limits to be set on the abundance: 10(-12)-10(-17) per atom in the solar system over the mass range of 20-10 000 amu.
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Affiliation(s)
- P Mueller
- Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
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38
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Abstract
Loss of deoxyribonuclease I (Dnase1) function is associated with systemic lupus erythematosus (SLE) in humans and mice; however, no coding mutations in Dnase1 are found in polygenic murine models. Instead, both MRL-lpr strains and NZB/W F1 hybrids are homozygous for T89I missense in the macrophage-DNASE, desoxyribonuclease I-like 3 (Dnase1l3). By in vitro expression studies, this substitution decreases this enzyme's nuclease activity against free DNA by only approximately twofold; however, the mutation has a greater effect on the capacity of media conditioned with Dnase1l3 to confer a barrier to liposomal gene transfection to HeLa cells. The 89I substitution decreases the Dnase1l3 barrier function in vitro by eightfold (P < 0.01). In splenocytes and BM-derived macrophages of SLE mice, while cellular Dnase1l3 levels are induced relative to C57BL/6 (control) mice, levels of FD-nuclease activity are similar. Finally, media conditioned by MRL and NZB/W F1 macrophages, relative to control, contains a weak interferon-gamma (IFN-gamma) inducible Dnase1l3-associated barrier to transfection. This barrier function is hypothesized to reflect the inability of SLE mice to degrade membrane-enveloped DNA-associated antigens, such as apoptotic bodies, which are predicted to stimulate the characteristic autoimmunity of SLE. Our results for these two generally independent models strongly suggest that Dnase1l3 deficiency increases the susceptibility of these mice to polygenic SLE.
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Affiliation(s)
- A Wilber
- Division of Genetics and Metabolism, Southern Illinois University School of Medicine, Springfield, IL 62794, USA
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Levy S, O'Connor TP, Hanscom JL, Shields P. Utility of an in-office C6 ELISA test kit for determination of infection status of dogs naturally exposed to Borrelia burgdorferi. Vet Ther 2003; 3:308-15. [PMID: 12447839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
Serologic evaluation for the diagnosis of Lyme disease has been confounded by several factors, including a high prevalence of clinically normal dogs testing seropositive, persistence of antibodies, and the introduction of vaccines that will induce antibodies detectable by immunofluorescent antibody assay, whole-cell ELISA, and Western blot assay. The utility of a commercially available in-office test kit (SNAP 3Dx, IDEXX Laboratories) for the simultaneous detection of Borrelia burgdorferi and Ehrlichia canis antibodies and Dirofilaria immitis antigen was evaluated for its ability to detect exposure to B. burgdorferi in both vaccinated and unvaccinated dogs from a highly Lyme-endemic area of Connecticut. The test kit is an ELISA that uses a synthetic peptide (C6) that duplicates the sequence of the IR6 region. The in-office C6 ELISA kit was found to be particularly useful in Lyme-endemic areas because it can be used conveniently and reliably in the clinic to determine a dog's infection status regardless of the vaccination history of the animal.
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Affiliation(s)
- Steven Levy
- Durham Veterinary Hospital, PC, Durham, CT 06422, USA
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Levy SA, O'Connor TP, Hanscom JL, Shields P. Evaluation of a canine C6 ELISA Lyme disease test for the determination of the infection status of cats naturally exposed to Borrelia burgdorferi. Vet Ther 2003; 4:172-7. [PMID: 14506593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
The efficacy of a commercially available in-office kit (SNAP 3Dx, IDEXX Laboratories) for detection of antibodies directed against an invariable region (IR6) of the B. burgdorferi surface protein VlsE (Vmp-like sequence, Expressed), a surface antigen of the spirochete recognized during active infection has been evaluated in dogs. The present study was conducted to determine whether this in-office test could be useful for detection of antibodies to B. burgdorferi in cats. Cats owned by clients of a veterinary hospital located in an area hyperendemic for Lyme disease were included in the study. When possible, cats with an outdoor lifestyle, bite wounds, or current tick infestation were recruited for the study to help ensure that animals with a likelihood of exposure to natural infection by B. burgdorferi would be included in the test group. Of the 24 cats tested, 17 samples were positive for antibodies to B. burgdorferi by the C6 ELISA kit. For all 17 of these samples, a duplicate sample tested by immunofluorescent assay (IFA) was in agreement with the ELISA. Five samples were negative by both assays. Two samples that were negative by the C6 ELISA test had low IFA titers (1:100). One of these two discrepant samples was negative and one was positive for antibodies to B. burgdorferi by the Western blot test. It was concluded that the C6 ELISA test performed with good agreement with the IFA and Western blot tests for detection of antibody to B. burgdorferi in the majority of cats tested. The test offers the advantages of producing a result rapidly (approximately 8 minutes), and it requires only two drops of serum, plasma, or whole blood.
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Affiliation(s)
- Steven A Levy
- Durham Veterinary Hospital PC, 178 Parmelee Hill Road, Durham, CT 06422, USA
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Beliaeff B, O'Connor TP, Munschy C, Raffin B, Claisse D. Comparison of polycyclic aromatic hydrocarbon levels in mussels and oysters in France and the United States. Environ Toxicol Chem 2002; 21:1783-1787. [PMID: 12206416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This paper compares data of 15 individual polycyclic aromatic hydrocarbon (PAH) concentrations from two monitoring programs: the French Rdseau National d'Observation de la qualité du milieu marin (RNO) and the Mussel Watch project of the U.S. National Status and Trends (NST) program. Polycyclic aromatic hydrocarbon measurements in bivalve (mussels and oysters) are made from samples collected at 265 sites along the U.S. coastline and at 97 sites in the French coastal waters. Individual PAH patterns were found strikingly similar between the two countries with higher concentrations for high-molecular-weight (HMW) PAHs. Principal component analysis results for both RNO and NST show the variability to be dominated by just two components with HMW compounds contributing primarily to the first and low-molecular-weight (LMW) compounds to the second. This could imply a separation of petrogenic and pyrolytic sources with the latter being the more important in both nations accounting for the similarity in results.
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O'Connor TP, Coleman JE. Proton nuclear magnetic resonance (500 MHz) of mono-, di-, tri- and tetradeoxynucleotide complexes of gene 5 protein. Biochemistry 2002. [DOI: 10.1021/bi00283a011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
Since 1986 the NOAA National Status and Trends (NS&T) Program Mussel Watch has monitored concentrations of trace chemicals in the coastal United States by sampling mussels, oysters, and sediment. The sediment data have been used to define the status or geographic distribution of chemical concentrations (Daskalakis, K. D., & O'Connor, T. P. (1995). Distribution of chemical contamination in coastal and estuarine sediments. Marine Environmental Research 40, 381-398) and the molluscan data have provided an estimate of temporal trends (O'Connor, T. P. (1996). Trends in chemical concentrations in mussels and oysters collected along the US coast from 1986 to 1993. Marine Environmental Research 41,183-200, O'Connor, T. P. (1998). Mussel Watch results from 1986 to 1996. Marine Pollution Bulletin 37, 14-19). This paper centers on chemical concentrations in mollusks at 263 sites around the United States. It provides perspective on concentration ranges and on geographic distributions. For most organic chemicals and lead, concentrations vary in proportion to numbers of people living near a site. For elements, other than lead, high concentrations in mollusks can be due more to natural factors than to human activity. Concentrations of PAHs in tissues of mussels from urban areas are in a range reported to exert biological responses.
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Affiliation(s)
- Thomas P O'Connor
- National Status and Trends Program, NOAA N/SCI1, Silver Spring, MD 20910, USA.
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Lauenstein GG, Cantillo AY, O'Connor TP. The status and trends of trace element and organic contaminants in oysters, Crassostrea virginica, in the waters of the Carolinas, USA. Sci Total Environ 2002; 285:79-87. [PMID: 11874050 DOI: 10.1016/s0048-9697(01)00897-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Concentrations of eight trace elements (As, Cd, Cu, Hg, Ni, Pb, Se and Zn), lindane and six groups of organic contaminants (total-chlordane, total-PCB, total-DDT, Dieldrin and Aldrin, total-butyltins, total-PAHs) at the 11 NOAA mussel watch project (MWP) sites located in North and South Carolina have been compared with the national US MWP data. Three sites from North and South Carolina had concentrations of PAHs in the upper 15th percentile on a national scale. One site had high concentrations of butyltins, and two sites had high Se concentrations. All sites from Beaufort, North Carolina, south had high As concentrations. Decreasing temporal trends were found for As, Cd, total-chlordane, DDT, PCB, and PAHs at some sites.
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Affiliation(s)
- Gunnar G Lauenstein
- Center for Coastal Monitoring and Assessment, National Centers for Coastal Ocean Science, NOAA/National Ocean Service, Silver Spring, MD 20910, USA
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45
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Bonner J, O'Connor TP. The permissive cue laminin is essential for growth cone turning in vivo. J Neurosci 2001; 21:9782-91. [PMID: 11739586 PMCID: PMC6763034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
The proper guidance of migrating growth cones relies on the balance of multiple guidance cues in the embryonic environment. In addition to guidance cues, growth cones are in contact with other substrates that may contribute to the pathfinding of neurons. For example, in the developing insect peripheral nervous system, pioneer neurons migrate on and between layers of the basal lamina. Previous studies have demonstrated that one basal lamina molecule, laminin, promotes outgrowth of many classes of neurons in vitro. In this study, the simple grasshopper nervous system was used to investigate the role of laminin in neuronal pathfinding. Laminin expression precedes axonogenesis of the Tibial (Ti1) pioneer neurons in the developing limb bud, and expression continues during outgrowth and guidance of the pioneer neurons. The role of a nidogen-binding motif on laminin was investigated using subunit-specific antibodies and peptides as blocking reagents in vivo. Antibodies and peptides that block the nidogen-binding site on laminin resulted in stalled Ti1 axon migration, predominantly at the precise location where they normally turn ventrally. After prolonged culturing, Ti1 axons remained stalled at the same location. Therefore, although Ti1 axons were capable of outgrowth in the presence of blocking reagents, they were not able to navigate an essential turn. This study indicates that the interaction of the Ti1 growth cone with the nidogen-binding site on laminin is vital for neuronal pathfinding in vivo and suggests that permissive cues may be essential for growth cone steering.
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Affiliation(s)
- J Bonner
- Department of Anatomy, Program in Neuroscience, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
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Abstract
The relationship between resting energy expenditure (REE) (kJ/d) and body mass (M) (kg) is a cornerstone in the study of energy physiology. By expressing REE as a function of body mass observed across mammals, Kleiber formulated the now classic equation: REE = 293M(0.75). The biological processes underlying Kleiber's law have been a topic of long-standing interest and speculation. In the present report we develop a new perspective of Kleiber's law by developing an organ-tissue level REE model consisting of five components: liver, brain, kidneys, heart and remaining tissues. The resting thermal output of each component is the product of the component's specific resting metabolic rate (K) and mass (T). With increasing body size, the K values for all five components had negative exponents and were directly proportional to M(-0.08--0.27), and all component T values were directly proportional to M(0.76-1.01). The resulting exponents of the product (K x T) were M(0.60-0.86) for the five components. Although the (K x T) values of individual components do not scale equally, their combined formula (286M(0.76)) is similar to that observed by Kleiber on the whole-body level. Modeling mammalian REE at the organ-tissue level provides new insights and pathways for future mechanistic explorations of REE-body composition relationships.
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Affiliation(s)
- Z Wang
- Obesity Research Center, St. Luke's-Roosevelt Hospital, Columbia University, College of Physicians and Surgeons, New York, NY 10025, USA.
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O'Connor TP. Comparing episodic, chronic, fishing, and non-fishing impacts on resource populations. Mar Pollut Bull 2001; 42:532-535. [PMID: 11488233 DOI: 10.1016/s0025-326x(00)00227-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Affiliation(s)
- T P O'Connor
- NOAA, N/SCI1, National Status and Trends Program, 1305 East West Highway, Silver Spring, MD 20910, USA.
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Bonner J, O'Connor TP. Semaphorin function in the developing invertebrate peripheral nervous system. Biochem Cell Biol 2001; 78:603-11. [PMID: 11103951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
Different members of the semaphorin family of secreted and transmembrane guidance molecules play important and diverse roles during neuronal development. Within the developing grasshopper limb bud, two semaphorins are expressed in relatively non-overlapping and distinct expression patterns. The establishment of the tibial sensory projection within the limb bud relies on the combinatorial action of both semaphorins. In this review, we describe the function of the two semaphorins in axonal guidance and propose that a hierarchy of cues guide sensory neurons in the developing peripheral nervous system.
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Affiliation(s)
- J Bonner
- Department of Anatomy, University of British Columbia, Vancouver, Canada
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Isbister CM, O'Connor TP. Mechanisms of growth cone guidance and motility in the developing grasshopper embryo. J Neurobiol 2000; 44:271-80. [PMID: 10934328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/15/2023]
Abstract
During neuronal pathfinding in vivo, growth cones must reorient their direction of migration in response to extracellular guidance cues. The developing grasshopper limb bud has proved to be a model system in which to examine mechanisms of growth cone guidance and motility in vivo. In this review we examine the contributions of adhesion and multiple guidance cues (semaphorins 1 and 2) in directing a growth cone steering event. Recent observations have suggested that the tibial pioneer growth cones are not directed via mechanisms of differential adhesivity. We present a model of growth cone steering that suggests a combination of adhesive and guidance receptors are important for a correct steering event and that guidance molecules may be important regulators of adhesive interactions with the actin cytoskeleton.
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Affiliation(s)
- C M Isbister
- Program in Neuroscience, Department of Anatomy, University of British Columbia, 2177 Wesbrook Mall, Vancouver, BC V6T 1Z3, Canada
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50
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O'Donoghue JM, O'Sullivan ST, O'Shaughnessy M, O'Connor TP. Effects of a silicone-coated polyamide net dressing and calcium alginate on the healing of split skin graft donor sites: a prospective randomised trial. Acta Chir Plast 2000; 42:3-6. [PMID: 10815307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
An open randomised prospectively controlled trial was performed to assess the healing efficacy, slippage rate and degree of discomfort on removal of calcium alginate and a silicone-coated polyamide net dressing on split skin graft donor sites. Sixteen patients were randomised to the calcium alginate group and 14 to the silicone-coated group. The donor sites were assessed at days 7, 10, 14 and up to day 21. The mean time to healing in the calcium alginate group was 8.75 +/- 0.78 days (range 7 to 14 days) compared to 12 +/- 0.62 days (range 7 to 16 days) for the silicone-coated group (p < 0.01). Although more silicone-coated dressings slipped (5 versus 1), the difference was not statistically significant. Pain during the first dressing change was assessed using a visual analogue pain scale. Although no significant differences were found between the groups, it was necessary to change the dressing protocol in the silicone-coated arm of the trial after entering the first two patients. Overlaid absorbent gauze adhered to the donor site through the fenestrations in the dressing necessitating the placement of paraffin gauze between the experimental dressing and the overlying cotton gauze. There was one infection in the study, occurring in the alginate group. Based on these results we recommend calcium alginate as the dressing of choice for split skin graft donor sites.
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Affiliation(s)
- J M O'Donoghue
- Department of Plastic Surgery, Cork University Hospital, Wilton, Ireland
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