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Janhunen P, Toivanen PK, Polkko J, Merikallio S, Salminen P, Haeggström E, Seppänen H, Kurppa R, Ukkonen J, Kiprich S, Thornell G, Kratz H, Richter L, Krömer O, Rosta R, Noorma M, Envall J, Lätt S, Mengali G, Quarta AA, Koivisto H, Tarvainen O, Kalvas T, Kauppinen J, Nuottajärvi A, Obraztsov A. Invited article: Electric solar wind sail: toward test missions. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:111301. [PMID: 21133454 DOI: 10.1063/1.3514548] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The electric solar wind sail (E-sail) is a space propulsion concept that uses the natural solar wind dynamic pressure for producing spacecraft thrust. In its baseline form, the E-sail consists of a number of long, thin, conducting, and centrifugally stretched tethers, which are kept in a high positive potential by an onboard electron gun. The concept gains its efficiency from the fact that the effective sail area, i.e., the potential structure of the tethers, can be millions of times larger than the physical area of the thin tethers wires, which offsets the fact that the dynamic pressure of the solar wind is very weak. Indeed, according to the most recent published estimates, an E-sail of 1 N thrust and 100 kg mass could be built in the rather near future, providing a revolutionary level of propulsive performance (specific acceleration) for travel in the solar system. Here we give a review of the ongoing technical development work of the E-sail, covering tether construction, overall mechanical design alternatives, guidance and navigation strategies, and dynamical and orbital simulations.
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Willeke H, Richter L. The effect of parity and litter size on the “on-the-farm” performance tested gilts. ACTA ACUST UNITED AC 2010. [DOI: 10.1111/j.1439-0388.1979.tb00196.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Edelstein M, Buchwald F, Richter L, Kramer S. Integrating background knowledge from internet databases into predictive toxicology models. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2010; 21:21-35. [PMID: 20373212 DOI: 10.1080/10629360903560579] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
While data integration for data analysis has been investigated extensively in biological applications, it has not yet been so much the focus in computational chemistry and quantitative structure-activity relationship (QSAR) research. With the availability and growing number of chemical databases on the web, such data integration efforts become an intriguing possibility (and, in fact, a necessity). In this paper, we take a first step towards the following vision and scenario for predictive toxicology applications. Given a new structure to be predicted, the first step would be to gather (integrate) all relevant information from internet databases for the structure itself, and all structures with available information for the endpoint of interest. In a second step, the collected information is combined statistically into a prediction of the new structure. We simulate this scenario with three endpoints (data sets) from the DSSTox database and collect information from three public chemical databases: PubChem, ChemBank and Sigma-Aldrich. In the experiments, we investigate whether the addition of background knowledge from the three databases can improve predictive performance (over using chemical structure alone) in a statistically significant way. For this purpose, we define groups of features (belonging together from an application point of view) from the three databases, and perform a variant of forward selection to include these feature groups in a prediction model. Our experiments show that the integration of background knowledge from internet databases can significantly improve prediction performance, especially for regression tasks.
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Schneider D, Bronsch K, Richter L. Olaquindox - ein neuer Wachstumspromotor in der Tierernährung. ACTA ACUST UNITED AC 2009. [DOI: 10.1111/j.1439-0396.1975.tb01140.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Chandan U, Richter L. Strengthening families through early intervention in high HIV prevalence countries. AIDS Care 2009; 21 Suppl 1:76-82. [PMID: 22380981 PMCID: PMC2903776 DOI: 10.1080/09540120902923097] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2009] [Accepted: 03/25/2009] [Indexed: 11/24/2022]
Abstract
Families have been at the forefront of the response to the HIV/AIDS epidemic in high-prevalence countries. They have also borne the greatest costs associated with the epidemic, including impoverishment, which has strained their capacity to care for vulnerable members. Within this context, there is consensus that strengthening the capacity of families to care for children is one of the most important strategies for mitigating the impacts of the HIV/AIDS epidemic on children's lives in high-prevalence countries. It is argued that evidence-based early intervention programmes that enhance caregiving and link caregivers with supports and services can play a pivotal role in strengthening families. Based on a systematic review, we recommend that two intervention strategies that should be given consideration within the context of high-prevalence countries, because of their demonstrated benefits in other settings, are nurse home visiting for first time, low-income pregnant mothers and their young children as well as early childhood development programmes for low-income children and families.
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Clayton T, Chen JL, Ernst M, Richter L, Cromer BA, Morton CJ, Ng H, Kaczorowski CC, Helmstetter FJ, Furtmüller R, Ecker G, Parker MW, Sieghart W, Cook JM. An updated unified pharmacophore model of the benzodiazepine binding site on gamma-aminobutyric acid(a) receptors: correlation with comparative models. Curr Med Chem 2008; 14:2755-75. [PMID: 18045122 DOI: 10.2174/092986707782360097] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A successful unified pharmacophore/receptor model which has guided the synthesis of subtype selective compounds is reviewed in light of recent developments both in ligand synthesis and structural studies of the binding site itself. The evaluation of experimental data in combination with a comparative model of the alpha1beta2gamma2 GABA(A) receptor leads to an orientation of the pharmacophore model within the Bz BS. Results not only are important for the rational design of selective ligands, but also for the identification and evaluation of possible roles which specific residues may have within the benzodiazepine binding pocket.
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Clark BC, Arvidson RE, Gellert R, Morris RV, Ming DW, Richter L, Ruff SW, Michalski JR, Farrand WH, Yen A, Herkenhoff KE, Li R, Squyres SW, Schröder C, Klingelhöfer G, Bell JF. Evidence for montmorillonite or its compositional equivalent in Columbia Hills, Mars. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006je002756] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Squyres SW, Arvidson RE, Bollen D, Bell JF, Brückner J, Cabrol NA, Calvin WM, Carr MH, Christensen PR, Clark BC, Crumpler L, Des Marais DJ, d'Uston C, Economou T, Farmer J, Farrand WH, Folkner W, Gellert R, Glotch TD, Golombek M, Gorevan S, Grant JA, Greeley R, Grotzinger J, Herkenhoff KE, Hviid S, Johnson JR, Klingelhöfer G, Knoll AH, Landis G, Lemmon M, Li R, Madsen MB, Malin MC, McLennan SM, McSween HY, Ming DW, Moersch J, Morris RV, Parker T, Rice JW, Richter L, Rieder R, Schröder C, Sims M, Smith M, Smith P, Soderblom LA, Sullivan R, Tosca NJ, Wänke H, Wdowiak T, Wolff M, Yen A. Overview of the Opportunity Mars Exploration Rover Mission to Meridiani Planum: Eagle Crater to Purgatory Ripple. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2006je002771] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Abstract
Insulin- and amino acid-induced signalling by the mammalian target of rapamycin (mTOR) involves hyperphosphorylation of the p70 ribosomal S6 protein kinase (p70S6-kinase) and the eukaryotic initiation factor 4E (eIF4E) binding protein 4E-BP1 and contributes to regulation of protein metabolism. This review considers the impact of cell hydration on mTOR-dependent signalling. Although hypoosmotic hepatocyte swelling in some instances activates p70S6-kinase, the hypoosmolarity-induced proteolysis inhibition in perfused rat liver is insensitive to mTOR inhibition by rapamycin. Likewise, swelling-dependent proteolysis inhibition by insulin and swelling-independent proteolysis inhibition by leucine, a potent activator of p70S6-kinase and 4E-BP1 hyperphosphorylation, in perfused rat liver is insensitive to rapamycin, indicating that at least rapamycin-sensitive mTOR signalling is not involved. Hyperosmotic dehydration in different cell types produces inactivation of signalling components around mTOR, thereby attenuating insulin-induced glucose uptake, glycogen synthesis, and lipogenesis in adipocytes, and MAP-kinase phosphatase MKP-1 expression in hepatoma cells. Direct inactivation of mTOR, stimulation of the AMP-activated protein kinase, and the destabilization of individual proteins may impair mTOR signalling under dehydrating conditions. Further investigation of the crosstalk between the mTOR pathway(s) and hyperosmotic signalling will improve our understanding about the contribution of cell hydration changes in health and disease and will provide further rationale for fluid therapy of insulin-resistant states.
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Marculescu R, Richter L, Rappersberger K. Infektionen mit Herpes-simplex- und Varicella-zoster-Viren in der Schwangerschaft. Hautarzt 2006; 57:207-12, 214-6. [PMID: 16514526 DOI: 10.1007/s00105-006-1105-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Primary infections with herpes simplex virus (HSV) and varicella-zoster virus (VZV) may lead to severe illness in pregnancy. Both diseases may be associated with transplacental virus transmission and fetal infection. Such infections can lead to intrauterine death, severe malformations and premature birth; the fetal/congenital varicella syndrome is well-defined. Herpes genitalis and varicella at the time of labor may lead to life threatening neonatal-herpes or varicella of the newborn. Currently neither active immunization nor neutralizing immunoglobulin is available for HSV infections. VZV-seronegative women in child-bearing age can be vaccinated and pregnant women exposed to VZV can be given specific immunoglobulins. While an infection is rarely blocked, the severity is generally reduced. For severe disease antiviral treatment is necessary, with valacyclovir and acyclovir represents the drugs of choice. Primary or recurrent overt disease of the genital tract at the time of delivery an indication for caesarean section. Suppression of recurrent genital herpes during the last weeks of pregnancy with valacyclovir and acyclovir reduces the need for surgical intervention. Neonates exposed to VZV should receive specific immunoglobulin. If neonates show signs of either infection, immediate treatment with acyclovir must be initiated.
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Cabrol NA, Farmer JD, Grin EA, Richter L, Soderblom L, Li R, Herkenhoff K, Landis GA, Arvidson RE. Aqueous processes at Gusev crater inferred from physical properties of rocks and soils along the Spirit traverse. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005je002490] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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63
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Arvidson RE, Squyres SW, Anderson RC, Bell JF, Blaney D, Brückner J, Cabrol NA, Calvin WM, Carr MH, Christensen PR, Clark BC, Crumpler L, Des Marais DJ, de Souza PA, d'Uston C, Economou T, Farmer J, Farrand WH, Folkner W, Golombek M, Gorevan S, Grant JA, Greeley R, Grotzinger J, Guinness E, Hahn BC, Haskin L, Herkenhoff KE, Hurowitz JA, Hviid S, Johnson JR, Klingelhöfer G, Knoll AH, Landis G, Leff C, Lemmon M, Li R, Madsen MB, Malin MC, McLennan SM, McSween HY, Ming DW, Moersch J, Morris RV, Parker T, Rice JW, Richter L, Rieder R, Rodionov DS, Schröder C, Sims M, Smith M, Smith P, Soderblom LA, Sullivan R, Thompson SD, Tosca NJ, Wang A, Wänke H, Ward J, Wdowiak T, Wolff M, Yen A. Overview of the Spirit Mars Exploration Rover Mission to Gusev Crater: Landing site to Backstay Rock in the Columbia Hills. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005je002499] [Citation(s) in RCA: 202] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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64
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65
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Squyres SW, Arvidson RE, Bell JF, Brückner J, Cabrol NA, Calvin W, Carr MH, Christensen PR, Clark BC, Crumpler L, Marais DJD, d'Uston C, Economou T, Farmer J, Farrand W, Folkner W, Golombek M, Gorevan S, Grant JA, Greeley R, Grotzinger J, Haskin L, Herkenhoff KE, Hviid S, Johnson J, Klingelhöfer G, Knoll AH, Landis G, Lemmon M, Li R, Madsen MB, Malin MC, McLennan SM, McSween HY, Ming DW, Moersch J, Morris RV, Parker T, Rice JW, Richter L, Rieder R, Sims M, Smith M, Smith P, Soderblom LA, Sullivan R, Wänke H, Wdowiak T, Wolff M, Yen A. The Opportunity Rover's Athena science investigation at Meridiani Planum, Mars. Science 2004; 306:1698-703. [PMID: 15576602 DOI: 10.1126/science.1106171] [Citation(s) in RCA: 132] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The Mars Exploration Rover Opportunity has investigated the landing site in Eagle crater and the nearby plains within Meridiani Planum. The soils consist of fine-grained basaltic sand and a surface lag of hematite-rich spherules, spherule fragments, and other granules. Wind ripples are common. Underlying the thin soil layer, and exposed within small impact craters and troughs, are flat-lying sedimentary rocks. These rocks are finely laminated, are rich in sulfur, and contain abundant sulfate salts. Small-scale cross-lamination in some locations provides evidence for deposition in flowing liquid water. We interpret the rocks to be a mixture of chemical and siliciclastic sediments formed by episodic inundation by shallow surface water, followed by evaporation, exposure, and desiccation. Hematite-rich spherules are embedded in the rock and eroding from them. We interpret these spherules to be concretions formed by postdepositional diagenesis, again involving liquid water.
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66
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Arvidson RE, Anderson RC, Bartlett P, Bell JF, Christensen PR, Chu P, Davis K, Ehlmann BL, Golombek MP, Gorevan S, Guinness EA, Haldemann AFC, Herkenhoff KE, Landis G, Li R, Lindemann R, Ming DW, Myrick T, Parker T, Richter L, Seelos FP, Soderblom LA, Squyres SW, Sullivan RJ, Wilson J. Localization and physical property experiments conducted by Opportunity at Meridiani Planum. Science 2004; 306:1730-3. [PMID: 15576608 DOI: 10.1126/science.1104211] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The location of the Opportunity landing site was determined to better than 10-m absolute accuracy from analyses of radio tracking data. We determined Rover locations during traverses with an error as small as several centimeters using engineering telemetry and overlapping images. Topographic profiles generated from rover data show that the plains are very smooth from meter- to centimeter-length scales, consistent with analyses of orbital observations. Solar cell output decreased because of the deposition of airborne dust on the panels. The lack of dust-covered surfaces on Meridiani Planum indicates that high velocity winds must remove this material on a continuing basis. The low mechanical strength of the evaporitic rocks as determined from grinding experiments, and the abundance of coarse-grained surface particles argue for differential erosion of Meridiani Planum.
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67
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Herkenhoff KE, Squyres SW, Arvidson R, Bass DS, Bell JF, Bertelsen P, Ehlmann BL, Farrand W, Gaddis L, Greeley R, Grotzinger J, Hayes AG, Hviid SF, Johnson JR, Jolliff B, Kinch KM, Knoll AH, Madsen MB, Maki JN, McLennan SM, McSween HY, Ming DW, Rice JW, Richter L, Sims M, Smith PH, Soderblom LA, Spanovich N, Sullivan R, Thompson S, Wdowiak T, Weitz C, Whelley P. Evidence from Opportunity's Microscopic Imager for water on Meridiani Planum. Science 2004; 306:1727-30. [PMID: 15576607 DOI: 10.1126/science.1105286] [Citation(s) in RCA: 118] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The Microscopic Imager on the Opportunity rover analyzed textures of soils and rocks at Meridiani Planum at a scale of 31 micrometers per pixel. The uppermost millimeter of some soils is weakly cemented, whereas other soils show little evidence of cohesion. Rock outcrops are laminated on a millimeter scale; image mosaics of cross-stratification suggest that some sediments were deposited by flowing water. Vugs in some outcrop faces are probably molds formed by dissolution of relatively soluble minerals during diagenesis. Microscopic images support the hypothesis that hematite-rich spherules observed in outcrops and soils also formed diagenetically as concretions.
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Soderblom LA, Anderson RC, Arvidson RE, Bell JF, Cabrol NA, Calvin W, Christensen PR, Clark BC, Economou T, Ehlmann BL, Farrand WH, Fike D, Gellert R, Glotch TD, Golombek MP, Greeley R, Grotzinger JP, Herkenhoff KE, Jerolmack DJ, Johnson JR, Jolliff B, Klingelhöfer G, Knoll AH, Learner ZA, Li R, Malin MC, McLennan SM, McSween HY, Ming DW, Morris RV, Rice JW, Richter L, Rieder R, Rodionov D, Schröder C, Seelos FP, Soderblom JM, Squyres SW, Sullivan R, Watters WA, Weitz CM, Wyatt MB, Yen A, Zipfel J. Soils of Eagle Crater and Meridiani Planum at the Opportunity Rover Landing Site. Science 2004; 306:1723-6. [PMID: 15576606 DOI: 10.1126/science.1105127] [Citation(s) in RCA: 138] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The soils at the Opportunity site are fine-grained basaltic sands mixed with dust and sulfate-rich outcrop debris. Hematite is concentrated in spherules eroded from the strata. Ongoing saltation exhumes the spherules and their fragments, concentrating them at the surface. Spherules emerge from soils coated, perhaps from subsurface cementation, by salts. Two types of vesicular clasts may represent basaltic sand sources. Eolian ripples, armored by well-sorted hematite-rich grains, pervade Meridiani Planum. The thickness of the soil on the plain is estimated to be about a meter. The flatness and thin cover suggest that the plain may represent the original sedimentary surface.
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Squyres SW, Arvidson RE, Bell JF, Brückner J, Cabrol NA, Calvin W, Carr MH, Christensen PR, Clark BC, Crumpler L, Des Marais DJ, D'Uston C, Economou T, Farmer J, Farrand W, Folkner W, Golombek M, Gorevan S, Grant JA, Greeley R, Grotzinger J, Haskin L, Herkenhoff KE, Hviid S, Johnson J, Klingelhöfer G, Knoll A, Landis G, Lemmon M, Li R, Madsen MB, Malin MC, McLennan SM, McSween HY, Ming DW, Moersch J, Morris RV, Parker T, Rice JW, Richter L, Rieder R, Sims M, Smith M, Smith P, Soderblom LA, Sullivan R, Wänke H, Wdowiak T, Wolff M, Yen A. The Spirit Rover's Athena science investigation at Gusev Crater, Mars. SCIENCE (NEW YORK, N.Y.) 2004; 305:794-9. [PMID: 15297657 DOI: 10.1126/science.1100194] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The Mars Exploration Rover Spirit and its Athena science payload have been used to investigate a landing site in Gusev crater. Gusev is hypothesized to be the site of a former lake, but no clear evidence for lacustrine sedimentation has been found to date. Instead, the dominant lithology is basalt, and the dominant geologic processes are impact events and eolian transport. Many rocks exhibit coatings and other characteristics that may be evidence for minor aqueous alteration. Any lacustrine sediments that may exist at this location within Gusev apparently have been buried by lavas that have undergone subsequent impact disruption.
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Arvidson RE, Anderson RC, Bartlett P, Bell JF, Blaney D, Christensen PR, Chu P, Crumpler L, Davis K, Ehlmann BL, Fergason R, Golombek MP, Gorevan S, Grant JA, Greeley R, Guinness EA, Haldemann AFC, Herkenhoff K, Johnson J, Landis G, Li R, Lindemann R, McSween H, Ming DW, Myrick T, Richter L, Seelos FP, Squyres SW, Sullivan RJ, Wang A, Wilson J. Localization and physical properties experiments conducted by Spirit at Gusev Crater. Science 2004; 305:821-4. [PMID: 15297662 DOI: 10.1126/science.1099922] [Citation(s) in RCA: 144] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The precise location and relative elevation of Spirit during its traverses from the Columbia Memorial station to Bonneville crater were determined with bundle-adjusted retrievals from rover wheel turns, suspension and tilt angles, and overlapping images. Physical properties experiments show a decrease of 0.2% per Mars solar day in solar cell output resulting from deposition of airborne dust, cohesive soil-like deposits in plains and hollows, bright and dark rock coatings, and relatively weak volcanic rocks of basaltic composition. Volcanic, impact, aeolian, and water-related processes produced the encountered landforms and materials.
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71
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Greeley R, Squyres SW, Arvidson RE, Bartlett P, Bell JF, Blaney D, Cabrol NA, Farmer J, Farrand B, Golombek MP, Gorevan SP, Grant JA, Haldemann AFC, Herkenhoff KE, Johnson J, Landis G, Madsen MB, McLennan SM, Moersch J, Rice JW, Richter L, Ruff S, Sullivan RJ, Thompson SD, Wang A, Weitz CM, Whelley P. Wind-related processes detected by the Spirit Rover at Gusev Crater, Mars. Science 2004; 305:810-3. [PMID: 15297660 DOI: 10.1126/science.1100108] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Wind-abraded rocks, ripples, drifts, and other deposits of windblown sediments are seen at the Columbia Memorial Station where the Spirit rover landed. Orientations of these features suggest formative winds from the north-northwest, consistent with predictions from atmospheric models of afternoon winds in Gusev Crater. Cuttings from the rover Rock Abrasion Tool are asymmetrically distributed toward the south-southeast, suggesting active winds from the north-northwest at the time (midday) of the abrasion operations. Characteristics of some rocks, such as a two-toned appearance, suggest that they were possibly buried and exhumed on the order of 5 to 60 centimeters by wind deflation, depending on location.
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72
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Grant JA, Arvidson R, Bell JF, Cabrol NA, Carr MH, Christensen P, Crumpler L, Des Marais DJ, Ehlmann BL, Farmer J, Golombek M, Grant FD, Greeley R, Herkenhoff K, Li R, McSween HY, Ming DW, Moersch J, Rice JW, Ruff S, Richter L, Squyres S, Sullivan R, Weitz C. Surficial Deposits at Gusev Crater Along Spirit Rover Traverses. Science 2004; 305:807-10. [PMID: 15297659 DOI: 10.1126/science.1099849] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The Mars Exploration Rover Spirit has traversed a fairly flat, rock-strewn terrain whose surface is shaped primarily by impact events, although some of the landscape has been altered by eolian processes. Impacts ejected basaltic rocks that probably were part of locally formed lava flows from at least 10 meters depth. Some rocks have been textured and/or partially buried by windblown sediments less than 2 millimeters in diameter that concentrate within shallow, partially filled, circular impact depressions referred to as hollows. The terrain traversed during the 90-sol (martian solar day) nominal mission shows no evidence for an ancient lake in Gusev crater.
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Squyres SW, Arvidson RE, Bell JF, Brückner J, Cabrol NA, Calvin W, Carr MH, Christensen PR, Clark BC, Crumpler L, Des Marais DJ, d'Uston C, Economou T, Farmer J, Farrand W, Folkner W, Golombek M, Gorevan S, Grant JA, Greeley R, Grotzinger J, Haskin L, Herkenhoff KE, Hviid S, Johnson J, Klingelhöfer G, Knoll A, Landis G, Lemmon M, Li R, Madsen MB, Malin MC, McLennan SM, McSween HY, Ming DW, Moersch J, Morris RV, Parker T, Rice JW, Richter L, Rieder R, Sims M, Smith M, Smith P, Soderblom LA, Sullivan R, Wänke H, Wdowiak T, Wolff M, Yen A. The Spirit Rover's Athena Science Investigation at Gusev Crater, Mars. Science 2004. [DOI: 10.1126/science.3050794] [Citation(s) in RCA: 337] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Daniels WMU, Richter L, Stein DJ. The effects of repeated intra-amygdala CRF injections on rat behavior and HPA axis function after stress. Metab Brain Dis 2004; 19:15-23. [PMID: 15214502 DOI: 10.1023/b:mebr.0000027413.42946.61] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Patients diagnosed with certain anxiety disorders or depression show symptoms of a dysregulated HPA-axis secondary to increased release of corticotropin releasing factor (CRF). Male Wistar rats were injected with CRF (100 ng/microL) in the basolateral amygdala (BLA) for 5 days. Measurement of behavior was performed on the elevated plus maze and open field test. Behavioral and neuroendocrine response to restraint stress was also evaluated. Chronic treatment of CRF resulted in a significant increase in grooming after restraint stress in the Open Field test. Basal plasma corticosterone concentrations were significantly lower in the CRF-injected rats. These animals also showed greater and longer increase in corticosterone levels following the restraint stress than controls, but had comparable ACTH responses to restraint stress. Our results indicate that chronic administration of CRF into the basolateral amygdala may promote stress-induced grooming behavior in rats. In addition the data suggests that increased CRF in the amygdala may contribute to the dysregulation of corticosterone secretion. These findings may have important implications for patients suffering from psychiatric illnesses such as posttraumatic stress disorder and depression that are characterized by abnormalities in cortisol release.
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75
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Gorevan SP, Myrick T, Davis K, Chau JJ, Bartlett P, Mukherjee S, Anderson R, Squyres SW, Arvidson RE, Madsen MB, Bertelsen P, Goetz W, Binau CS, Richter L. Rock Abrasion Tool: Mars Exploration Rover mission. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2003je002061] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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