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Luo D, Ma X, Du P, Chen Z, Lin Q, Liu Y, Niu B, He X, Wang X. Reconstructing Solvation Structure by Steric Hindrance-Coordination Push-Pull of Dipolymer-H2O-Zn2+ toward Long-life Aqueous Zinc-Metal Batteries. Angew Chem Int Ed Engl 2024:e202401163. [PMID: 38702974 DOI: 10.1002/anie.202401163] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 04/28/2024] [Accepted: 05/03/2024] [Indexed: 05/06/2024]
Abstract
Aqueous zinc-metal batteries are prospective energy storge devices due to their intrinsically high safety and cost effectiveness. Yet, uneven deposition of zinc ions in electrochemical reduction and side reactions at the anode interface significantly hinder their development and application. Here, we propose a solvation-interface attenuation strategy enabled by a frustrated tertiary amine amphiphilic dipolymer electrolyte additive. The configuration of superhydrophilic segments with covalently bonded lipophilic spacers enables coupled steric hindrance/coordination, which establishes a balanced push-pull dynamic of dipolymer-H2O-Zn2+. Such interplay reconstructs the solvation structure of Zn2+ and allows the formation of a stable dipolymer-inorganic hybrid solid electrolyte interface (SEI) layer. This SEI layer effectively shields the zinc-metal anode from water and anions, significantly reducing side reactions. In addition, the dipolymer adsorbed at the zinc-metal anode interface regulates the interfacial electrochemical reduction kinetics and ensures uniform zinc deposition. As a result, the Zn-Zn symmetric cells with dipolymer-containing electrolyte exhibit remarkable cycling stability exceeding 5800 h (242 days). The Zn-NVO batteries and Zn-AC hybrid ion supercapacitors also deliver stable cycling for up to 1440 h (60 days) with high-capacity retention over 80%. This research demonstrates the potential to facilitate the development and commercialization of zinc-based energy storage devices.
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Affiliation(s)
- Die Luo
- Southwest Petroleum University, School of New Energy and Materials, CHINA
| | - Xinyu Ma
- Southwest Petroleum University, School of New Energy and Materials, CHINA
| | - Pan Du
- Southwest Petroleum University, School of New Energy and Materials, CHINA
| | - Zuo Chen
- Southwest Petroleum University, School of New Energy and Materials, CHINA
| | - Qiurui Lin
- Southwest Petroleum University, School of New Energy and Materials, CHINA
| | - Yuhan Liu
- Southwest Petroleum University, School of New Energy and Materials, CHINA
| | - Ben Niu
- Songshan Lake Materials Laboratory, Songshan Lake Materials Laboratory, CHINA
| | - Xianru He
- Southwest Petroleum University, New Energy and Materials, Xindu Road, No.8, 610500, Chengdu, CHINA
| | - Xin Wang
- Songshan Lake Materials Laboratory, Songshan Lake Materials Laboratory, CHINA
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Brotherton AR, Shibu A, Meadows JC, Sayresmith NA, Brown CE, Ledezma AM, Schmedake TA, Walter MG. Leveraging Coupled Solvatofluorochromism and Fluorescence Quenching in Nitrophenyl-Containing Thiazolothiazoles for Efficient Organic Vapor Sensing. Adv Sci (Weinh) 2023:e2205729. [PMID: 37186373 DOI: 10.1002/advs.202205729] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 02/26/2023] [Indexed: 05/17/2023]
Abstract
Solvatofluorochromic molecules provide strikingly high fluorescent outputs to monitor a wide range of biological, environmental, or materials-related sensing processes. Here, thiazolo[5,4-d]thiazole (TTz) fluorophores equipped with simple alkylamino and nitrophenyl substituents for solid-state, high-performance chemo-responsive sensing applications are reported. Nitroaromatic substituents are known to strongly quench dye fluorescence, however, the TTz core subtly modulates intramolecular charge transfer (ICT) enabling strong, locally excited-state fluorescence in non-polar conditions. In polar media, a planar ICT excited-state shows near complete quenching, enabling a twisted excited-state emission to be observed. These unique fluorescent properties (spectral shifts of 0.13 - 0.87 eV and large transition dipole moments Δµ = 20.4 - 21.3 D) are leveraged to develop highly sought-after chemo-responsive, organic vapor optical sensors. The sensors are developed by embedding the TTz fluorophores within a poly(styrene-isoprene-styrene) block copolymer to form fluorescent dye/polymer composites (ΦF = 70 - 97%). The composites respond reversibly to a comprehensive list of organic solvents and show low vapor concentration sensing (e.g., 0.04% solvent saturation vapor pressure of THF - 66 ppm). The composite films can distinguish between solvent vapors with near complete fluorescent quenching observed when exposed to their saturated solvent vapor pressures, making this an extremely promising material for optical chemo-responsive sensing.
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Affiliation(s)
- Andrew R Brotherton
- Department of Chemistry, University of North Carolina at Charlotte, Charlotte, NC, 28223, USA
| | - Abhishek Shibu
- Department of Chemistry, University of North Carolina at Charlotte, Charlotte, NC, 28223, USA
| | - Jared C Meadows
- Department of Chemistry, University of North Carolina at Charlotte, Charlotte, NC, 28223, USA
| | - Nickolas A Sayresmith
- Department of Chemistry, University of North Carolina at Charlotte, Charlotte, NC, 28223, USA
| | - Chloe E Brown
- Department of Chemistry, University of North Carolina at Charlotte, Charlotte, NC, 28223, USA
| | - Ana Montoya Ledezma
- Department of Chemistry, University of North Carolina at Charlotte, Charlotte, NC, 28223, USA
| | - Thomas A Schmedake
- Department of Chemistry, University of North Carolina at Charlotte, Charlotte, NC, 28223, USA
| | - Michael G Walter
- Department of Chemistry, University of North Carolina at Charlotte, Charlotte, NC, 28223, USA
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Niu Y, Han S, Wu Z, Pan C, Wang M, Tang Y, Zhang QH, Tan G, Han B. A push-pull strategy for controlling the tea green leafhopper (Empoasca flavescens F.) using semiochemicals from Tagetes erecta and Flemingia macrophylla. Pest Manag Sci 2022; 78:2161-2172. [PMID: 35179311 DOI: 10.1002/ps.6840] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 02/14/2022] [Accepted: 02/18/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND The tea green leafhopper, Empoasca flavescens is the most important pest in Chinese tea plantations. For decades its control has been executed almost exclusively through pesticide applications. A semiochemical-based 'push-pull' strategy was tested on the leafhopper in the study. RESULTS The odors released from Tagetes erecta and Flemingia macrophylla significantly repelled and attracted leafhoppers, respectively. These volatile compounds (46 from T. erecta and 53 F. macrophylla) were identified and quantified via gas chromatography-mass spectometry (GC-MS) analysis. Y-tube olfactometer assays indicated that thymol anisole, thymol and camphor had significant repellent effects on the leafhoppers, resulting in a ternary repellent blend at a 4:3:13 ratio. Cis-3-hexen-1-ol, cis-3-hexenyl acetate, nonanal and α-farnesene were significantly attractive to the leafhoppers, making an attractant blend at a 17:4:1:1 ratio. In the field, the push-pull strategy with the repellent dispensers placed within the tea bushes and the attractant-baited sticky traps hung 15 cm above the tea plants showed a significant control efficacy, reaching 69% and 55% at two and 14 days post-treatment, respectively, similar to those in the insecticide control plots. Additionally, the leafhopper density in the push-pull intercropping plot was 63.2 leafhoppers/100 tea shoots/visit, much lower than those in the pull intercropping plot and nonintercropping plot. CONCLUSION Application of the push-pull strategy using both synthetic repellent and attractant, or intercropping T. erecta and F. macrophylla with tea plants, can effectively reduce the leafhopper population. This approach might have great potential as an environmentally safe control strategy against the leafhopper. © 2022 Society of Chemical Industry.
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Affiliation(s)
- Yuqun Niu
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, College of Plant Protection, Anhui Agricultural University, Hefei, China
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection and Quarantine, College of Life Sciences, China Jiliang University, Hangzhou, China
| | - Shanjie Han
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection and Quarantine, College of Life Sciences, China Jiliang University, Hangzhou, China
| | - Zihui Wu
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection and Quarantine, College of Life Sciences, China Jiliang University, Hangzhou, China
| | - Cheng Pan
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection and Quarantine, College of Life Sciences, China Jiliang University, Hangzhou, China
| | - Mengxin Wang
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection and Quarantine, College of Life Sciences, China Jiliang University, Hangzhou, China
| | - Yanyan Tang
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection and Quarantine, College of Life Sciences, China Jiliang University, Hangzhou, China
| | | | - Genjia Tan
- Anhui Province Key Laboratory of Integrated Pest Management on Crops, College of Plant Protection, Anhui Agricultural University, Hefei, China
| | - Baoyu Han
- Zhejiang Provincial Key Laboratory of Biometrology and Inspection and Quarantine, College of Life Sciences, China Jiliang University, Hangzhou, China
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Sekaran B, Dawson A, Jang Y, MohanSingh KV, Misra R, D'Souza F. Charge-Transfer in Panchromatic Porphyrin-Tetracyanobuta-1,3-Diene-Donor Conjugates: Switching the Role of Porphyrin in the Charge Separation Process. Chemistry 2021; 27:14335-14344. [PMID: 34375474 DOI: 10.1002/chem.202102865] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [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: 08/06/2021] [Indexed: 11/09/2022]
Abstract
Using a combination of cycloaddition-retroelectrocyclization reaction, free-base and zinc porphyrins (H2 P and ZnP) are decorated at their β-pyrrole positions with strong charge transfer complexes, viz., tetracyanobuta-1,3-diene (TCBD)-phenothiazine (3 and 4) or TCBD-aniline (7 and 8), novel class of push-pull systems. The physico-chemical properties of these compounds (MP-Donor and MP-TCBD-Donor) have been investigated using a range of electrochemical, spectroelectrochemical, DFT as well as steady-state and time-resolved spectroscopic techniques. Ground-state charge transfer interactions between the porphyrin and the electron-withdrawing TCBD directly attached to the porphyrin π-system extended the absorption features well into the near-infrared region. To visualize the photo-events, energy level diagrams with the help of free-energy calculations have been established. Switching the role of porphyrin from the initial electron acceptor to electron donor was possible to envision. Occurrence of photoinduced charge separation has been established by complementary transient absorption spectral studies followed by global and target data analyses. Better charge stabilization in H2 P derived over ZnP derived conjugates, and in phenothiazine derived over aniline derived conjugates has been possible to establish. These findings highlight the importance of the nature of porphyrins and second electron donor in governing the ground and excited state charge transfer events in closely positioned donor-acceptor conjugates.
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Affiliation(s)
- Bijesh Sekaran
- Department of Chemistry, Indian Institute of Technology, Indore, 453552, India
| | - Andrew Dawson
- Department of Chemistry, University of North Texas, 1155 Union Circle, #305070, Denton, TX 76203-5017, USA
| | - Youngwoo Jang
- Department of Chemistry, University of North Texas, 1155 Union Circle, #305070, Denton, TX 76203-5017, USA
| | - Kusum V MohanSingh
- Department of Chemistry, Indian Institute of Technology, Indore, 453552, India
| | - Rajneesh Misra
- Department of Chemistry, Indian Institute of Technology, Indore, 453552, India
| | - Francis D'Souza
- Department of Chemistry, University of North Texas, 1155 Union Circle, #305070, Denton, TX 76203-5017, USA
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Scheidegger L, Niassy S, Midega C, Chiriboga X, Delabays N, Lefort F, Zürcher R, Hailu G, Khan Z, Subramanian S. The role of Desmodium intortum, Brachiaria sp. and Phaseolus vulgaris in the management of fall armyworm Spodoptera frugiperda (J. E. Smith) in maize cropping systems in Africa. Pest Manag Sci 2021; 77:2350-2357. [PMID: 33421266 PMCID: PMC8048848 DOI: 10.1002/ps.6261] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 12/13/2020] [Accepted: 01/09/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) is a serious pest of maize. Farming systems such as push-pull or maize-legume intercropping have been reported to reduce FAW infestations significantly. However, the exact mechanisms involved in FAW management have not been practically elucidated. We therefore assessed larval host preference, feeding and survival rate when exposed to four host plants commonly used in push-pull and legume intercropping. We also compared adult moths' oviposition preference between maize and other grasses used as trap crops in push-pull. RESULTS The larval orientation and settlement study showed that maize was the most preferred host plant followed by bean, desmodium and Brachiaria brizantha cv Mulato II. The larval arrest and dispersal experiment showed that mean number of larvae was significantly higher on maize than on Desmodium or B. brizantha cv Mulato II. However, no significant differences were found between maize and bean after 24 h. Maize was the most consumed plant, followed by bean, desmodium and finally brachiaria. The mean percentage of survival to the pupation stage was significantly higher on maize. The study on FAW oviposition preference showed no significant differences in egg deposited between maize and other grasses. However, B. brizantha cv Xaraes, which received more eggs than maize, could be a promising alternative to B. brizantha cv Mulato II for the control of FAW. CONCLUSION The study provides a better understanding of the mechanisms involved in the control of fall armyworm under the push-pull and maize legume intercropping. © 2021 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Laetitia Scheidegger
- Haute école du paysage, d'ingénierie et d'architecture de GenèveGenevaSwitzerland
| | - Saliou Niassy
- International Centre of Insect Physiology and EcologyNairobiKenya
| | - Charles Midega
- International Centre of Insect Physiology and EcologyNairobiKenya
| | - Xavier Chiriboga
- International Centre of Insect Physiology and EcologyNairobiKenya
| | - Nicolas Delabays
- Haute école du paysage, d'ingénierie et d'architecture de GenèveGenevaSwitzerland
| | - François Lefort
- Haute école du paysage, d'ingénierie et d'architecture de GenèveGenevaSwitzerland
| | - Roger Zürcher
- Haute école du paysage, d'ingénierie et d'architecture de GenèveGenevaSwitzerland
| | - Girma Hailu
- International Centre of Insect Physiology and EcologyNairobiKenya
| | - Zeyaur Khan
- International Centre of Insect Physiology and EcologyNairobiKenya
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Paddock KJ, Robert CAM, Erb M, Hibbard BE. Western Corn Rootworm, Plant and Microbe Interactions: A Review and Prospects for New Management Tools. Insects 2021; 12:171. [PMID: 33671118 PMCID: PMC7922318 DOI: 10.3390/insects12020171] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 02/11/2021] [Accepted: 02/13/2021] [Indexed: 12/12/2022]
Abstract
The western corn rootworm, Diabrotica virgifera virgifera LeConte, is resistant to four separate classes of traditional insecticides, all Bacillius thuringiensis (Bt) toxins currently registered for commercial use, crop rotation, innate plant resistance factors, and even double-stranded RNA (dsRNA) targeting essential genes via environmental RNA interference (RNAi), which has not been sold commercially to date. Clearly, additional tools are needed as management options. In this review, we discuss the state-of-the-art knowledge about biotic factors influencing herbivore success, including host location and recognition, plant defensive traits, plant-microbe interactions, and herbivore-pathogens/predator interactions. We then translate this knowledge into potential new management tools and improved biological control.
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Affiliation(s)
- Kyle J. Paddock
- Division of Plant Sciences, University of Missouri, Columbia, MO 65211, USA;
| | - Christelle A. M. Robert
- Institute of Plant Sciences, University of Bern, 3013 Bern, Switzerland; (C.A.M.R.); (M.E.)
- Oeschger Centre for Climate Change Research, University of Bern, 3013 Bern, Switzerland
| | - Matthias Erb
- Institute of Plant Sciences, University of Bern, 3013 Bern, Switzerland; (C.A.M.R.); (M.E.)
- Oeschger Centre for Climate Change Research, University of Bern, 3013 Bern, Switzerland
| | - Bruce E. Hibbard
- Plant Genetics Research Unit, United States Department of Agriculture, Agricultural Research Service, Columbia, MO 65211, USA
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Mutisya MM, Agbodzavu MK, Kinyuru JN, Tanga CM, Gicheha M, Hailu G, Salifu D, Khan Z, Niassy S. Can black soldier fly Desmodium intortum larvae-based diets enhance the performance of Cobb500 broiler chickens and smallholder farmers' profit in Kenya? Poult Sci 2021; 100:420-430. [PMID: 33518093 PMCID: PMC7858130 DOI: 10.1016/j.psj.2020.11.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 09/29/2020] [Accepted: 11/09/2020] [Indexed: 12/02/2022] Open
Abstract
This study aimed to evaluate the performance of broiler chickens fed on 3 black soldier fly larvae (BSFL) (Hermetia illucens) and Greenleaf desmodium (Desmodium intortum)-based meals. We evaluated growth performance, carcass quality, and profitability under various commercial pathways (doorstep, retail, whole, and assorted). Desmodium and BSFL powders were formulated into 3 ratios: T1 25:75, T2 50:50, and T3 75:25. A commercial feed was used as a control. One hundred and twenty mixed-sex 1-day-old broiler chicks (Cobb) were reared in pens for 42 d in a completely randomized design. The chickens were weighed weekly to monitor their growth rate. After the 42-day rearing period, they were slaughtered for carcass quality evaluation and recording of the weights of internal organs. During the initial growth phase (7-21 d), significant effects of fish meal replacement were found on the chickens' average weight (P < 0.001), average daily body weight gain (P < 0.001), average daily feed intake (P < 0.001), and feed conversion ratio (P < 0.001). However, during the second phase (21-42 d), no significant effect of the replacement was detected except on average daily feed intake (P = 0.003). No significant differences were found in terms of the relative weights of internal organs. It was found that Desmodium-BSFL-based feeds were more profitable than the control feed, and the assorted and retail modes of sale generated more revenue compared to when the chickens were sold at doorstep and on whole-chicken basis. The return on investment was higher for a push-pull adopter compared to a non-adopter. The study found that a BSFL-Desmodium mixture can be a valuable replacement for the protein component in conventional feed and would provide a new impetus for the adoption of push-pull.
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Affiliation(s)
- Mary M Mutisya
- Plant Health Division, International Centre of Insect Physiology and Ecology (Icipe), Nairobi, Kenya; Department of Food Science and Technology, Jomo Kenyatta University of Agriculture and Technology (JKUAT), Nairobi, Kenya
| | - Mawufe K Agbodzavu
- Plant Health Division, International Centre of Insect Physiology and Ecology (Icipe), Nairobi, Kenya; International Institute of Tropical Agriculture (IITA), Kinshasa 4163, DR Congo
| | - John N Kinyuru
- Department of Food Science and Technology, Jomo Kenyatta University of Agriculture and Technology (JKUAT), Nairobi, Kenya
| | - Chrysantus M Tanga
- Plant Health Division, International Centre of Insect Physiology and Ecology (Icipe), Nairobi, Kenya
| | - Mathew Gicheha
- Department of Animal Science, Jomo Kenyatta University of Agriculture and Technology (JKUAT), Nairobi, Kenya
| | - Girma Hailu
- Plant Health Division, International Centre of Insect Physiology and Ecology (Icipe), Nairobi, Kenya
| | - Daisy Salifu
- Plant Health Division, International Centre of Insect Physiology and Ecology (Icipe), Nairobi, Kenya
| | - Zeyaur Khan
- Plant Health Division, International Centre of Insect Physiology and Ecology (Icipe), Nairobi, Kenya
| | - Saliou Niassy
- Plant Health Division, International Centre of Insect Physiology and Ecology (Icipe), Nairobi, Kenya.
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Perri DV, Gorosito NB, Schilman PE, Casaubón EA, Dávila C, Fernández PC. Push-pull to manage leaf-cutting ants: an effective strategy in forestry plantations. Pest Manag Sci 2021; 77:432-439. [PMID: 32770659 DOI: 10.1002/ps.6036] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 07/21/2020] [Accepted: 08/08/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Leaf-cutting ants (LCAs) are amongst the most important forestry pests in South America. Currently, their control is carried out almost exclusively through the application of toxic baits of restricted use. Here we evaluate a push-pull strategy (i.e., the simultaneous use of attractant and repellent stimuli in order to divert pests) to manage LCAs Acromyrmex spp. in young willow plantations in the area of Delta of the Parana River, Argentina, a wetland ecosystem. First, we surveyed ants' selection of farmland vegetation during one year. Then, we estimated ants' preferences between the willow Salix babylonica and a subsample of plant species from farmland vegetation under laboratory conditions. Finally, we designed and performed a fully crossed experimental field assay to evaluate a push-pull strategy by using farmland vegetation as pull stimulus. RESULTS We surveyed 39 plant species in the area, 19 of which had been foraged by LCAs along the year. Plants were selected by species, not by abundance. In the lab, ants showed similar preference for the cultivated willow and the subsample of plant species. Push-pull was the only treatment that maintained willow remaining vegetation above 60-80% at the end of the growing season. CONCLUSIONS For the first time the push-pull strategy was evaluated in social insects. We demonstrated that it can be successfully used to manage LCAs in young willow plantations. Our strategy generates biodiversity, which can improve the ecosystem functioning, and it can be easily implemented by producers since its design is based on regular willow plantations.
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Affiliation(s)
- Daiana V Perri
- Laboratorio de Ecofisiología de Insectos, DBBE, FCEN, Universidad de Buenos Aires e Instituto de Biodiversidad y de Biología Experimental y Aplicada (IBBEA), CONICET-UBA, Buenos Aires, Argentina
- Cátedra de Biomoléculas, Facultad de Agronomía, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Norma B Gorosito
- Laboratorio de Entomología Aplicada y Forense, Universidad Nacional de Quilmes, Bernal, Argentina
- Cátedra de Zoología Agrícola, Facultad de Agronomía, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Pablo E Schilman
- Laboratorio de Ecofisiología de Insectos, DBBE, FCEN, Universidad de Buenos Aires e Instituto de Biodiversidad y de Biología Experimental y Aplicada (IBBEA), CONICET-UBA, Buenos Aires, Argentina
| | - Edgardo A Casaubón
- Estación Experimental Agropecuaria Delta, Instituto Nacional de Tecnología Agropecuaria, Buenos Aires, Argentina
| | - Camila Dávila
- Cátedra de Biomoléculas, Facultad de Agronomía, Universidad de Buenos Aires, Buenos Aires, Argentina
- Instituto de Investigaciones en Biociencias Agrícolas y Ambientales, CONICET-UBA, Buenos Aires, Argentina
| | - Patricia C Fernández
- Cátedra de Biomoléculas, Facultad de Agronomía, Universidad de Buenos Aires, Buenos Aires, Argentina
- Estación Experimental Agropecuaria Delta, Instituto Nacional de Tecnología Agropecuaria, Buenos Aires, Argentina
- Centro de Investigaciones de Hidratos de Carbono (CIHIDECAR), CONICET-UBA, Buenos Aires, Argentina
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Noirbent G, Xu Y, Bonardi AH, Duval S, Gigmes D, Lalevée J, Dumur F. New Donor-Acceptor Stenhouse Adducts as Visible and Near Infrared Light Polymerization Photoinitiators. Molecules 2020; 25:E2317. [PMID: 32429126 PMCID: PMC7287840 DOI: 10.3390/molecules25102317] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 05/12/2020] [Accepted: 05/13/2020] [Indexed: 11/17/2022] Open
Abstract
Polymerization photoinitiators that can be activated under low light intensity and in the visible range are being pursued by both the academic and industrial communities. To efficiently harvest light and initiate a polymerization process, dyes with high molar extinction coefficients in the visible range are ideal candidates. In this field, Donor-acceptor Stenhouse Adducts (DASA) which belong to a class of recently discovered organic photochromic molecules still lack practical applications. In this work, a series of DASA-based dyes are proposed as photoinitiators for the free radical polymerization of (meth)acrylates upon exposure to a near infrared light (laser diode at 785 nm).
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Affiliation(s)
- Guillaume Noirbent
- Aix Marseille Univ, CNRS, ICR UMR 7273, F-13397 Marseille, France; (G.N.); (D.G.)
| | - Yangyang Xu
- Université de Haute-Alsace, CNRS, IS2M UMR 7361, F-68100 Mulhouse, France; (Y.X.); (A.-H.B.)
- Université de Strasbourg, F-67000 Strasbourg, France
| | - Aude-Héloise Bonardi
- Université de Haute-Alsace, CNRS, IS2M UMR 7361, F-68100 Mulhouse, France; (Y.X.); (A.-H.B.)
- Université de Strasbourg, F-67000 Strasbourg, France
| | - Sylvain Duval
- Université de Lille, CNRS, Centrale Lille, Univ. Artois, UMR 8181—UCCS—Unité de Catalyse et Chimie du Solide, F-59000 Lille, France;
| | - Didier Gigmes
- Aix Marseille Univ, CNRS, ICR UMR 7273, F-13397 Marseille, France; (G.N.); (D.G.)
| | - Jacques Lalevée
- Université de Haute-Alsace, CNRS, IS2M UMR 7361, F-68100 Mulhouse, France; (Y.X.); (A.-H.B.)
- Université de Strasbourg, F-67000 Strasbourg, France
| | - Frédéric Dumur
- Aix Marseille Univ, CNRS, ICR UMR 7273, F-13397 Marseille, France; (G.N.); (D.G.)
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10
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Stupp P, Rakes M, Oliveira DC, Martins LN, Geisler FCS, Ribeiro LP, Nava DE, Bernardi D. Acetogenin-Based Formulated Bioinsecticides on Anastrepha fraterculus: Toxicity and Potential Use in Insecticidal Toxic Baits. Neotrop Entomol 2020; 49:292-301. [PMID: 31907799 DOI: 10.1007/s13744-019-00747-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 12/05/2019] [Indexed: 06/10/2023]
Abstract
The present study evaluated the lethal toxicity and oviposition deterrence of ethanolic extracts of Annona mucosa Jacq., Annona muricata L., and Annona sylvatica A. St.-Hil on Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) compared with those of a limonoid-based bioinsecticide (Azamax™ 1.2 EC-azadiractin +3-tigloyl-azadiractol) and a synthetic spinosyn-based insecticide (Delegate™ 250 WG-spinetoram). In addition, the efficacy of the selected toxic bait formulations was evaluated by mixing them with food attractants (Anamed™, 3% Biofruit and 7% sugarcane molasses). In the topical application and ingestion bioassays (2000 mg L-1), the aqueous emulsion of the A. mucosa extract caused greater than 80% mortality of A. fraterculus adults in a similar manner to the spinosyn-based synthetic insecticide. Concentration-response curves were performed for the most promising treatments and showed an activity level dependent on the mode of contamination, exposure time, and applied concentration. In bioassays with and without choice, the A. mucosa (77%), A. muricata (51%), A. sylvatica (60%), Azamax™ (74%), and Delegate™ 250 WG (100%) significantly reduced the number of punctures and galleries in grape berries. In combination with the food attractants Anamed™, 3% Biofruit, and 7% sugarcane molasses, the emulsion of the A. mucosa extract had a residual effect similar to that of the spinetoram insecticide, with a mortality rate of over 80% of A. fraterculus adults up to 14 days after application (DAA) in the absence of rain. Thus, acetogenin-rich formulations, especially from A. mucosa seeds, are useful alternatives for the integrated management of A. fraterculus in agricultural orchards.
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Affiliation(s)
- P Stupp
- Department of Plant Protection, Federal Univ of Pelotas (UFPel), Pelotas, Rio Grande do Sul, Brasil
| | - M Rakes
- Department of Plant Protection, Federal Univ of Pelotas (UFPel), Pelotas, Rio Grande do Sul, Brasil
| | - D C Oliveira
- Department of Plant Protection, Federal Univ of Pelotas (UFPel), Pelotas, Rio Grande do Sul, Brasil
| | - L N Martins
- Department of Plant Protection, Federal Univ of Pelotas (UFPel), Pelotas, Rio Grande do Sul, Brasil
| | - F C S Geisler
- Department of Plant Protection, Federal Univ of Pelotas (UFPel), Pelotas, Rio Grande do Sul, Brasil
| | - L P Ribeiro
- Research Center for Family Agriculture, Agricultural Research and Rural Extension Company of Santa Catarina (EPAGRI/CEPAF), Florianópolis, Santa Catarina, Brasil
| | - D E Nava
- Brazilian Agricultural Research Corporation (EMBRAPA - Clima Temperado, CPACT), Pelotas, Rio Grande do Sul, Brasil
| | - D Bernardi
- Department of Plant Protection, Federal Univ of Pelotas (UFPel), Pelotas, Rio Grande do Sul, Brasil.
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11
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Cusumano A, Harvey JA, Bourne ME, Poelman EH, G de Boer J. Exploiting chemical ecology to manage hyperparasitoids in biological control of arthropod pests. Pest Manag Sci 2020; 76:432-443. [PMID: 31713945 PMCID: PMC7004005 DOI: 10.1002/ps.5679] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [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: 08/02/2019] [Revised: 11/05/2019] [Accepted: 11/05/2019] [Indexed: 05/02/2023]
Abstract
Insect hyperparasitoids are fourth trophic level organisms that commonly occur in terrestrial food webs, yet they are relatively understudied. These top-carnivores can disrupt biological pest control by suppressing the populations of their parasitoid hosts, leading to pest outbreaks, especially in confined environments such as greenhouses where augmentative biological control is used. There is no effective eco-friendly strategy that can be used to control hyperparasitoids. Recent advances in the chemical ecology of hyperparasitoid foraging behavior have opened opportunities for manipulating these top-carnivores in such a way that biological pest control becomes more efficient. We propose various infochemical-based strategies to manage hyperparasitoids. We suggest that a push-pull strategy could be a promising approach to 'push' hyperparasitoids away from their parasitoid hosts and 'pull' them into traps. Additionally, we discuss how infochemicals can be used to develop innovative tools improving biological pest control (i) to restrict accessibility of resources (e.g. sugars and alternative hosts) to primary parasitoid only or (ii) to monitor hyperparasitoid presence in the crop for early detection. We also identify important missing information in order to control hyperparasitoids and outline what research is needed to reach this goal. Testing the efficacy of synthetic infochemicals in confined environments is a crucial step towards the implementation of chemical ecology-based approaches targeting hyperparasitoids. © 2019 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Antonino Cusumano
- Laboratory of EntomologyWageningen UniversityWageningenThe Netherlands
| | - Jeffrey A Harvey
- Department of Terrestrial EcologyNetherlands Institute of Ecology (NIOO‐KNAW)WageningenThe Netherlands
- Department of Ecological Sciences, Section Animal EcologyVU University AmsterdamAmsterdamThe Netherlands
| | - Mitchel E Bourne
- Laboratory of EntomologyWageningen UniversityWageningenThe Netherlands
| | - Erik H Poelman
- Laboratory of EntomologyWageningen UniversityWageningenThe Netherlands
| | - Jetske G de Boer
- Department of Terrestrial EcologyNetherlands Institute of Ecology (NIOO‐KNAW)WageningenThe Netherlands
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12
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Johnson NS, Miehls SM, Haro AJ, Wagner CM. Push and pull of downstream moving juvenile sea lamprey ( Petromyzon marinus) exposed to chemosensory and light cues. Conserv Physiol 2019; 7:coz080. [PMID: 33133606 PMCID: PMC6883208 DOI: 10.1093/conphys/coz080] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 08/21/2019] [Accepted: 10/02/2019] [Indexed: 05/16/2023]
Abstract
Visual and olfactory stimuli induce behavioural responses in fishes when applied independently, but little is known about how simultaneous exposure influences behaviour, especially in downstream migrating fishes. Here, downstream moving juvenile sea lamprey (Petromyzon marinus) were exposed to light and a conspecific chemosensory alarm cue in a flume and movement were monitored with overhead cameras and nets. When exposed to light, sea lamprey were more likely to be captured in a net closest to the light array. When exposed to the alarm cue, sea lamprey transit rate through the flume increased, but sea lamprey did not avoid the alarm cue plume by moving perpendicular to flow. When the alarm cue and light were applied simultaneously in a push and pull configuration, the alarm cue still triggered enhanced downstream movement (push downstream) and more sea lamprey was still captured in the net nearest the light (pull to the side), resulting in twice as many sea lamprey being captured in the lighted net relative to controls. To our knowledge, this is the first study using multiple sensory cues in a push-pull configuration to modulate fish outmigration. Push and pull of juvenile sea lamprey with sensory cues could be useful to reduce turbine entrainment where native and enhance trap catch where invasive.
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Affiliation(s)
- Nicholas S Johnson
- Hammond Bay Biological Station, U.S. Geological Survey, Great Lakes Science Center, 11188 Ray Road, Millersburg, MI 49759, USA
- Corresponding author: U.S. Geological Survey, Great Lakes Science Center, Hammond Bay Biological Station, 11188 Ray Road, Millersburg, MI 49759, USA. Tel: 989-734-4768 x 128. Authors contributed equally
| | - Scott M Miehls
- Hammond Bay Biological Station, U.S. Geological Survey, Great Lakes Science Center, 11188 Ray Road, Millersburg, MI 49759, USA
| | - Alex J Haro
- S.O. Conte Anadromous Fish Research Laboratory, U.S. Geological Survey, Leetown Science Center, 1 Migratory Way, Turners Falls, MA 01376, USA
| | - C Michael Wagner
- Department of Fisheries and Wildlife, Michigan State University, Room 13, Natural Resources Building, East Lansing, MI 48824, USA
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13
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Abstract
Dye-sensitized solar cell (DSSC) has been attractive to scientific community due to its eco-friendliness, ease of fabrication, and vivid colorful property etc. Among various kinds of sensitizers, such as metal-free organic molecules, metal-complex, natural dyes etc., porphyrin is one of the most promising sensitizers for DSSC. The first application of porphyrin for sensitization of nanocrystaline TiO2 can be traced back to 1993 by using [tetrakis(4-carboxyphenyl) porphyrinato] zinc(II) with an overall conversion efficiency of 2.6%. After 10 years efforts, Officer and Grätzel improved this value to 7.1%. Later in 2009, by constructing porphyrin sensitizer with an arylamine as donor and a benzoic acid as acceptor, Diau and Yeh demonstrated that this donor-acceptor framwork porphyrins could attain remarkable photovoltaic performance. Now the highest efficiencies of DSSC are dominated by donor-acceptor porphyrins, reaching remarkable values around 13.0% with cobalt-based electrolytes. This achievement is largely contributed by the structural development of donor and acceptor groups within push-pull framwork. In this review, we summarized and discussed the developement of donor-acceptor porphyrin sensitizers and their applications in DSSC. A dicussion of the correlation between molecular structure and the spectral and photovoltaic properties is the major target of this review. Deeply dicussion of the substitution group, especially on porphyrin's meso-position were presented. Furthermore, the limitations of DSSC for commercialization, such as the long-term stability, sophisticated synthesis procedures for high efficiency dye etc., have also been discussed.
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Affiliation(s)
- Jianfeng Lu
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, China
- School of Chemistry, Monash University, Melbourne, VIC, Australia
| | - Shuangshuang Liu
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, China
| | - Mingkui Wang
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, China
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14
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Abstract
Blood sampling is a major source of blood loss in the pediatric intensive care unit (PICU). Blood-sparing sampling techniques such as the push-pull method can significantly reduce sampling-related blood loss and protect patients from anemia and blood transfusions. The push-pull method is supported by research evidence for central venous catheter (CVC) sampling, but research protocols differ and not all CVCs and laboratory tests have been studied. A standard push-pull protocol for the PICU was developed, implemented, and evaluated in this evidence-based practice project. Results show that the protocol can be used safely and reliably as a standard waste-free sampling method in the PICU.
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Affiliation(s)
- Clare McBride
- Oregon Health and Science University, Doernbecher Children's Hospital, Portland, Oregon (Ms McBride); Rady Children's Hospital, San Diego, California (Dr Miller-Hoover); and University of California at San Diego, Altman Clinical and Translational Research Institute, San Diego, California (Mr Proudfoot). Clare McBride, BSN, RN, CCRN, is a pediatric intensive care and cardiac nurse at Oregon Health and Science University's Doernbecher Children's Hospital. She previously worked at Rady Children's Hospital in San Diego and presented this evidence-based practice project at the American Association of Critical Care Nurses' annual teaching conference. Suzan Miller-Hoover, DNP, RN, CCNS, CCRN-K, has been in the nursing profession for more than 35 years. An experienced national speaker and peer-reviewed author, Dr Miller-Hoover is passionate about evidence-based best practice and pediatrics. James A. Proudfoot, MSc, is a senior statistician at the University of California at San Diego, Altman Clinical and Translational Research Institute. He has consulted on numerous clinical trials and is a coauthor of more than 25 articles
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15
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Wallingford AK, Cha DH, Loeb GM. Evaluating a push-pull strategy for management of Drosophila suzukii Matsumura in red raspberry. Pest Manag Sci 2018; 74:120-125. [PMID: 28714131 DOI: 10.1002/ps.4666] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 05/25/2017] [Accepted: 07/08/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND Drosophila suzukii Matsumura is a serious pest of small fruits that lays its eggs in growing fruit. Current management strategies rely on an unsustainable schedule of foliar applications of chemical insecticides. Alternative approaches to suppressing oviposition are under investigation, such as attract-and-kill and the use of oviposition deterrents. Here, we evaluated two behavioral control approaches in combination as a push-pull strategy using laboratory and field assays. RESULTS In laboratory caged assays, both an attractive mass trapping device (pull) and an oviposition deterrent (push: 1-octen-3-ol) reduced oviposition by D. suzukii, and the combination of the two (push-pull) resulted in significantly greater reduction than either treatment alone. In field experiments, oviposition reduction was observed in fruit from plots treated with oviposition deterrent (push) or a combination of mass trapping devices and deterrent (push-pull) compared with fruit from control plots. However, oviposition in plots with mass trapping devices (pull) was higher than observed in all other treatments. Additionally, the protection provided by the deterrent in push plots extended to the entire plot rather than just in fruit closest to deterrent dispensers. CONCLUSION Push-pull treatments negatively affected D. suzukii infestation in both laboratory and field experiments. The reduction in oviposition observed in laboratory experiments was based on the additive effect of push and pull components acting on a finite population, while the reduction observed in field experiments appeared to be mainly based on the effect of pull components. We discuss potential underlying reasons for the discrepancy results and suggest potential improvements. © 2017 Society of Chemical Industry.
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Affiliation(s)
- Anna K Wallingford
- Cornell University, New York Agricultural Experiment Station, Geneva, NY, USA
| | - Dong H Cha
- USDA-ARS, US Pacific Basin Agricultural Research Center, Hilo, HI, USA
| | - Gregory M Loeb
- Cornell University, New York Agricultural Experiment Station, Geneva, NY, USA
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16
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Vega FE, Simpkins A, Miranda J, Harnly JM, Infante F, Castillo A, Wakarchuk D, Cossé A. A Potential Repellent Against the Coffee Berry Borer (Coleoptera: Curculionidae: Scolytinae). J Insect Sci 2017; 17:122. [PMID: 0 PMCID: PMC5751034 DOI: 10.1093/jisesa/iex095] [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] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Indexed: 05/24/2023]
Abstract
The coffee berry borer, Hypothenemus hampei (Ferrari), continues to pose a formidable challenge to coffee growers worldwide. Because of the cryptic life habit of the insect inside coffee berries, effective pest management strategies have been difficult to develop. A sesquiterpene, (E,E)-α-farnesene, produced by infested coffee berries has been identified as a potential repellent against the coffee berry borer both in laboratory bioassays and a field experiment in Hawaii. Various laboratory bioassays revealed significantly lower levels of infestation in berries treated with different concentrations of the (E,E)-α-farnesene. A field experiment in Hawaii resulted in up to 80% decreased coffee berry borer captures in traps containing a standard 3:1 methanol:ethanol attractant and a bubble cap formulation of (E,E)-α-farnesene compared to traps with just the attractant. (E,E)-α-farnesene was still active 19 wk after installation in the coffee plantation, based on 59% lower insect captures in traps containing the attractant + (E,E)-α-farnesene (1,737 insects) compared to traps containing the attractant (4,253 insects). The easy to install bubble caps are a welcome contrast with other pest management strategies that require spraying. The placement of (E,E)-α-farnesene in bubble caps in coffee plantations when coffee berries first become susceptible to infestations (ca. 90 d post-flowering) might result in lower infestation levels throughout the season, and consequently, increased yields and profits.
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Affiliation(s)
- Fernando E Vega
- Sustainable Perennial Crops Laboratory, U. S. Department of Agriculture, Agricultural Research Service, Beltsville, MD
| | - Ann Simpkins
- Sustainable Perennial Crops Laboratory, U. S. Department of Agriculture, Agricultural Research Service, Beltsville, MD
| | - Jose Miranda
- Tropical Plant Genetic Resources and Disease Research Unit, U. S. Department of Agriculture, Agricultural Research Service, Pacific Basin Agricultural Research Center, Hilo, HI
| | - James M Harnly
- Food Composition and Methods Development Laboratory, U. S. Department of Agriculture, Agricultural Research Service, Beltsville, MD
| | | | - Alfredo Castillo
- El Colegio de la Frontera Sur (ECOSUR), Tapachula, Chiapas, México
| | | | - Allard Cossé
- Crop Bioprotection Research Unit, National Center for Agricultural Utilization Research, U. S. Department of Agriculture, Agricultural Research Service, Peoria, IL
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17
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Zhou L, Liu MZ, Li Q, Deng J, Mu D, Sun YG. Organization of Functional Long-Range Circuits Controlling the Activity of Serotonergic Neurons in the Dorsal Raphe Nucleus. Cell Rep 2017; 18:3018-3032. [PMID: 28329692 DOI: 10.1016/j.celrep.2017.02.077] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [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: 12/05/2016] [Revised: 01/26/2017] [Accepted: 02/24/2017] [Indexed: 10/19/2022] Open
Abstract
Serotonergic neurons play key roles in various biological processes. However, circuit mechanisms underlying tight control of serotonergic neurons remain largely unknown. Here, we systematically investigated the organization of long-range synaptic inputs to serotonergic neurons and GABAergic neurons in the dorsal raphe nucleus (DRN) of mice with a combination of viral tracing, slice electrophysiological, and optogenetic techniques. We found that DRN serotonergic neurons and GABAergic neurons receive largely comparable synaptic inputs from six major upstream brain areas. Upon further analysis of the fine functional circuit structures, we found both bilateral and ipsilateral patterns of topographic connectivity in the DRN for the axons from different inputs. Moreover, the upstream brain areas were found to bidirectionally control the activity of DRN serotonergic neurons by recruiting feedforward inhibition or via a push-pull mechanism. Our study provides a framework for further deciphering the functional roles of long-range circuits controlling the activity of serotonergic neurons in the DRN.
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Affiliation(s)
- Li Zhou
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, China; Graduate School, University of Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, China
| | - Ming-Zhe Liu
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, China; Graduate School, University of Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, China
| | - Qing Li
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, China
| | - Juan Deng
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, China; Graduate School, University of Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, China
| | - Di Mu
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, China; Graduate School, University of Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, China
| | - Yan-Gang Sun
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, China.
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18
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Hess S, Decker M. Comparison of the Single-Syringe Push-Pull Technique With the Discard Technique for Obtaining Blood Samples From Pediatric Central Venous Access Devices. J Pediatr Oncol Nurs 2017; 34:381-386. [PMID: 28681653 DOI: 10.1177/1043454217713453] [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] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The discard technique is the most widely used method of obtaining blood samples from patients with central venous access devices (CVADs), but risks removing more blood than is necessary for laboratory testing and may increase a patient's risk of anemia. We hypothesized that laboratory results from pediatric blood specimens obtained via CVAD using the single-syringe push-pull (formerly called the mixing) method and the discard method would be similar. Blood samples were obtained from pediatric oncology patients in a hospital setting using both collection methods and laboratory values were analyzed for concordance using the pairwise t-test, intraclass correlation coefficient, and Bland-Altman analysis methods. Statistical analysis revealed significant differences for sodium, potassium, chloride, bicarbonate, creatinine, calcium, white blood cell count, hemoglobin, hematocrit, and platelet count, but these differences were not clinically significant and within the standard error of measurement for the instrument. Given the similarity in laboratory results, the push-pull method should be considered for obtaining blood samples from CVADs in pediatric patients to avoid unnecessary blood loss.
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Affiliation(s)
- Sarah Hess
- 1 Marshfield Clinic, Marshfield, WI, USA.,2 Providence Health & Service, Family Medicine-Northpointe, Spokane, WA, USA
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19
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Schaub TA, Brülls SM, Dral PO, Hampel F, Maid H, Kivala M. Organic Electron Acceptors Comprising a Dicyanomethylene-Bridged Acridophosphine Scaffold: The Impact of the Heteroatom. Chemistry 2017; 23:6988-6992. [PMID: 28370820 DOI: 10.1002/chem.201701412] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [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: 03/30/2017] [Indexed: 01/25/2023]
Abstract
Stable two-electron acceptors comprising a dicyanomethylene-bridged acridophosphine scaffold were synthesized and their reversible reduction potentials were efficiently tuned through derivatization of the phosphorus center. X-ray crystallographic analysis combined with NMR, UV/Vis, IR spectroscopic, and electrochemical studies, supported by theoretical calculations, revealed the crucial role of the phosphorus atom for the unique redox, structural, and photophysical properties of these compounds. The results identify the potential of these electron deficient scaffolds for the development of functional n-type materials and redox active chromophores upon further functionalization.
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Affiliation(s)
- Tobias A Schaub
- Department of Chemistry and Pharmacy, Chair of Organic Chemistry I, University of Erlangen-Nürnberg, Henkestrasse 42, 91054, Erlangen, Germany
| | - Steffen M Brülls
- Department of Chemistry and Pharmacy, Chair of Organic Chemistry I, University of Erlangen-Nürnberg, Henkestrasse 42, 91054, Erlangen, Germany
| | - Pavlo O Dral
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
| | - Frank Hampel
- Department of Chemistry and Pharmacy, Chair of Organic Chemistry I, University of Erlangen-Nürnberg, Henkestrasse 42, 91054, Erlangen, Germany
| | - Harald Maid
- Department of Chemistry and Pharmacy, Chair of Organic Chemistry I, University of Erlangen-Nürnberg, Henkestrasse 42, 91054, Erlangen, Germany
| | - Milan Kivala
- Department of Chemistry and Pharmacy, Chair of Organic Chemistry I, University of Erlangen-Nürnberg, Henkestrasse 42, 91054, Erlangen, Germany
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20
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Pickett JA, Khan ZR. Plant volatile-mediated signalling and its application in agriculture: successes and challenges. New Phytol 2016; 212:856-870. [PMID: 27874990 DOI: 10.1111/nph.14274] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [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: 04/25/2016] [Accepted: 08/04/2016] [Indexed: 05/25/2023]
Abstract
856 I. 856 II. 857 III. 858 IV. 859 V. 860 VI. 862 VII. 863 VIII. 864 IX. 866 866 References 866 SUMMARY: The mediation of volatile secondary metabolites in signalling between plants and other organisms has long been seen as presenting opportunities for sustainable crop protection. Initially, exploitation of interactions between plants and other organisms, particularly insect pests, foundered because of difficulties in delivering, sustainably, the signal systems for crop protection. We now have mounting and, in some cases, clear practical evidence for successful delivery by companion cropping or next-generation genetic modification (GM). At the same time, the type of plant signalling being exploited has expanded to signalling from plants to organisms antagonistic to pests, and to plant stress-induced, or primed, plant-to-plant signalling for defence and growth stimulation.
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Affiliation(s)
- John A Pickett
- Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - Zeyaur R Khan
- Push-Pull Programme, International Centre of Insect Physiology and Ecology, PO Box 30, Mbita, 40305, Kenya
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21
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Andrews SS, Peria WJ, Yu RC, Colman-Lerner A, Brent R. Push-Pull and Feedback Mechanisms Can Align Signaling System Outputs with Inputs. Cell Syst 2016; 3:444-455.e2. [PMID: 27894998 DOI: 10.1016/j.cels.2016.10.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 06/10/2016] [Accepted: 10/04/2016] [Indexed: 11/23/2022]
Abstract
Many cell signaling systems, including the yeast pheromone response system, exhibit "dose-response alignment" (DoRA), in which output of one or more downstream steps closely matches the fraction of occupied receptors. DoRA can improve the fidelity of transmitted dose information. Here, we searched systematically for biochemical network topologies that produced DoRA. Most networks, including many containing feedback and feedforward loops, could not produce DoRA. However, networks including "push-pull" mechanisms, in which the active form of a signaling species stimulates downstream activity and the nominally inactive form reduces downstream activity, enabled perfect DoRA. Networks containing feedbacks enabled DoRA, but only if they also compared feedback to input and adjusted output to match. Our results establish push-pull as a non-feedback mechanism to align output with variable input and maximize information transfer in signaling systems. They also suggest genetic approaches to determine whether particular signaling systems use feedback or push-pull control.
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22
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Kuhns EH, Martini X, Hoyte A, Stelinski LL. Repellent Activity of Botanical Oils against Asian Citrus Psyllid, Diaphorina citri (Hemiptera: Liviidae). Insects 2016; 7:insects7030035. [PMID: 27429006 PMCID: PMC5039548 DOI: 10.3390/insects7030035] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 06/30/2016] [Accepted: 07/11/2016] [Indexed: 11/16/2022]
Abstract
The Asian citrus psyllid, Diaphorina citri Kuwayama, is the insect vector of the pathogen causing huanglongbing. We selected three botanical oils to evaluate behavioral activity against D. citri. In laboratory olfactometer assays, fir oil was repellent to D. citri females, while litsea and citronella oils elicited no response from D. citri females. In choice settling experiments, D. citri settled almost completely on control plants rather than on plants treated with fir oil at a 9.5 mg/day release rate. Therefore, we conducted field trials to determine if fir oil reduced D. citri densities in citrus groves. We found no repellency of D. citri from sweet orange resets that were treated with fir oil dispensers releasing 10.4 g/day/tree as compared with control plots. However, we found a two-week decrease in populations of D. citri as compared with controls when the deployment rate of these dispensers was doubled. Our results suggest that treatment of citrus with fir oil may have limited activity as a stand-alone management tool for D. citri and would require integration with other management practices.
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Affiliation(s)
- Emily H Kuhns
- Citrus Research and Education Center, Entomological and Nematology Department, University of Florida, 700 Experimentation road, Lake Alfred, FL 33850, USA.
| | - Xavier Martini
- Citrus Research and Education Center, Entomological and Nematology Department, University of Florida, 700 Experimentation road, Lake Alfred, FL 33850, USA.
- North Florida Research and Education Center, Entomological and Nematology Department, University of Florida, 155 Experiment Road, Quincy, FL 32351, USA.
| | - Angel Hoyte
- Citrus Research and Education Center, Entomological and Nematology Department, University of Florida, 700 Experimentation road, Lake Alfred, FL 33850, USA.
| | - Lukasz L Stelinski
- Citrus Research and Education Center, Entomological and Nematology Department, University of Florida, 700 Experimentation road, Lake Alfred, FL 33850, USA.
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Guarino S, Colazza S, Peri E, Bue PL, Germanà MP, Kuznetsova T, Gindin G, Soroker V. Behaviour-modifying compounds for management of the red palm weevil (Rhynchophorus ferrugineus Oliver). Pest Manag Sci 2015; 71:1605-1610. [PMID: 25523649 DOI: 10.1002/ps.3966] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 12/13/2014] [Accepted: 12/13/2014] [Indexed: 06/04/2023]
Abstract
BACKGROUND Populations of red palm weevil (RPW), a severe pest of palms in Mediterranean countries, might be limited by semiochemical-based behaviour-disrupting methods. We evaluated the effects of electroantennogram (EAG)-active plant volatiles on the behaviour of RPWs from Italy and Israel. In field experiments, α-pinene, citronellol, geraniol, citral and 1-octen-3-ol were tested for their ability to disrupt attraction to pheromone-kairomone and molasses baited traps. Those that were found to be disruptive in the field were evaluated in a laboratory choice bioassay in individual cages for their effect on RPW female feeding and oviposition. RESULTS Field experiments showed reduced captures in traps loaded with geraniol (-57%), 1-octen-3-ol (-50%) or α-pinene (-45% to -60%); captures in citronellol- or citral-loaded traps did not differ from control. In laboratory experiments, 1-octen-3-ol was the most potent behaviour-modifying compound, eliciting a significant/marginally significant reduction in both feeding and oviposition at the lowest dose tested in both populations. Geraniol generally caused a strong reduction in feeding and oviposition at each dose tested (Israel), or at the highest dose (Italy). α-Pinene caused some reduction in feeding activity at the highest dose tested (Italy), but no consistent repellency (Israel). CONCLUSION Field and laboratory data suggest the potential for the use of 1-octen-3-ol, geraniol and α-pinene for RPW population management.
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Affiliation(s)
- Salvatore Guarino
- Dipartimento di Scienze Agrarie e Forestali, Università degli Studi di Palermo, Palermo, Italy
- Istituto per la Protezione Sostenibile delle Piante (IPSP), Sesto Fiorentino, Florence, Italy
| | - Stefano Colazza
- Dipartimento di Scienze Agrarie e Forestali, Università degli Studi di Palermo, Palermo, Italy
| | - Ezio Peri
- Dipartimento di Scienze Agrarie e Forestali, Università degli Studi di Palermo, Palermo, Italy
| | - Paolo Lo Bue
- Dipartimento di Scienze Agrarie e Forestali, Università degli Studi di Palermo, Palermo, Italy
| | - Maria Pia Germanà
- Dipartimento di Scienze Agrarie e Forestali, Università degli Studi di Palermo, Palermo, Italy
| | | | - Galina Gindin
- Volcani Centre, Agricultural Research Organisation, Bet Dagan, Israel
| | - Victoria Soroker
- Volcani Centre, Agricultural Research Organisation, Bet Dagan, Israel
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24
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Ruggunan SD, Singh S. Sector switching among histopathologists in KwaZulu-Natal, South Africa: a qualitative study. Hum Resour Health 2013; 11:23. [PMID: 23721129 PMCID: PMC3671983 DOI: 10.1186/1478-4491-11-23] [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] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 05/16/2013] [Indexed: 06/02/2023]
Abstract
BACKGROUND The mobility of health care professionals from the public to private sector is prevalent in South Africa. However, literature on sector switching of clinical doctors remains limited. It is against this background that this study aims to make the labour market visible for histopathologists and identify the reasons for sector switching. METHODS This study is exploratory and descriptive. It uses qualitative methods, such as in-depth interviews, with 70% (n = 16/23) of the population of histopathologists in KwaZulu-Natal, South Africa. Lee's (1966) push-pull theory is adapted to explain the pull sector switching behaviours of histopathologists. Interviews were recorded and independently transcribed. The narratives of the participants were coded to reflect the main themes that contributed to their sector switching behaviours. RESULTS Five key themes emerged as reasons for the mobility of histopathologists from the public to private sector in KwaZulu-Natal. The findings indicate that remuneration, working conditions, work flexibility, career pathing and autonomy of labour processes are the key drivers of this mobility. CONCLUSIONS Histopathologists provide a core function in the health care chain. However, their invisibility in academic discourse in both public health and human resources for health indicates the paucity of research undertaken on the importance of these specialists in the health care chain. This is especially significant in developing countries like South Africa, where there is a dearth of these specialists. This study, while exploratory, aims to open a dialogue to better understand their reasons for sector switching and, hopefully, inform policies on training, recruitment and retention of these specialists.
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Affiliation(s)
- Shaun D Ruggunan
- Discipline of Human Resources Management, University of KwaZulu-Natal, University Road, Durban, 4000, South Africa
| | - Suveera Singh
- Programme for Industrial, Organisational and Labour Studies, University of KwaZulu-Natal, Mazisi Kunene Road, Durban, 4041, South Africa
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25
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Bodenlenz M, Aigner B, Dragatin C, Liebenberger L, Zahiragic S, Höfferer C, Birngruber T, Priedl J, Feichtner F, Schaupp L, Korsatko S, Ratzer M, Magnes C, Pieber TR, Sinner F. Clinical applicability of dOFM devices for dermal sampling. Skin Res Technol 2013; 19:474-83. [PMID: 23581539 DOI: 10.1111/srt.12071] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/23/2013] [Indexed: 11/29/2022]
Abstract
BACKGROUND Sampling the dermal interstitial fluid (ISF) allows the pharmacokinetics and pharmacodynamics of dermatological drugs to be studied directly at their site of action. Dermal open-flow microperfusion (dOFM) is a recently developed technique that can provide minimally invasive, continuous, membrane-free (thus unfiltered) access to the dermal ISF. Herein, we evaluate the clinical applicability and reliability of novel wearable dOFM devices in a clinical setting. METHODS Physicians inserted 141 membrane-free dOFM probes into the dermis of 17 healthy and psoriatic volunteers and sampled dermal ISF for 25 h by using wearable push-pull pumps. The tolerability, applicability, reproducibility, and reliability of multiple insertions and 25 h continuous sampling was assessed by pain scoring, physician feedback, ultrasound probe depth measurements, and 25 h-drift and variability of the sodium relative recovery. RESULTS Insertion pain was moderate and decreased with each additional probe. Probe insertion was precise, although slightly deeper in lesional skin. The wearable push-pull pump enabled uninterrupted ISF sampling over 25 h with low variability. The relative recovery was drift-free and highly reproducible. CONCLUSION dOFM sampling devices are tolerable and reliable for prolonged continuous dermal sampling in a multiprobe clinical setting. These devices should enable the study of a wide range of drugs and their biomarkers in the skin.
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Affiliation(s)
- M Bodenlenz
- HEALTH - Institute for Biomedicine and Health Sciences, Joanneum Research Forschungsgesellschaft m.b.H., Graz, Austria
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26
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Kulhánek J, Bures F, Ludwig M. Convenient methods for preparing pi-conjugated linkers as building blocks for modular chemistry. Beilstein J Org Chem 2009; 5:11. [PMID: 19478966 PMCID: PMC2686302 DOI: 10.3762/bjoc.5.11] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [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: 02/12/2009] [Accepted: 04/07/2009] [Indexed: 11/23/2022] Open
Abstract
Simple, straightforward and optimized procedures for preparing extended pi-conjugated linkers are described. Either unsubstituted or 4-donor substituted pi-linkers bearing a styryl, biphenyl, phenylethenylphenyl, and phenylethynylphenyl pi-conjugated backbone are functionalized with boronic pinacol esters as well as with terminal acetylene moieties allowing their further use as building blocks in Suzuki-Miyaura or Sonogashira coupling reactions.
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Affiliation(s)
- Jirí Kulhánek
- Institute of Organic Chemistry and Technology, Faculty of Chemical Technology, University of Pardubice, nám Cs. legií 565, Pardubice, 532 10, Czech Republic
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27
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Lee PJ, Granata KP. Interface stability influences torso muscle recruitment and spinal load during pushing tasks. Ergonomics 2006; 49:235-48. [PMID: 16540437 PMCID: PMC1630675 DOI: 10.1080/00140130500485285] [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] [Indexed: 05/07/2023]
Abstract
Handle or interface design can influence torso muscle recruitment and spinal load during pushing tasks. The objective of the study was to provide insight into the role of interface stability with regard to torso muscle recruitment and biomechanical loads on the spine. Fourteen subjects generated voluntary isometric trunk flexion force against a rigid interface and similar flexion exertions against an unstable interface, which simulated handle design in a cart pushing task. Normalized electromyographic (EMG) activity in the rectus abdominus, external oblique and internal oblique muscles increased with exertion effort. When using the unstable interface, EMG activity in the internal and external oblique muscle groups was greater than when using the rigid interface. Results agreed with trends from a biomechanical model implemented to predict the muscle activation necessary to generate isometric pushing forces and maintain spinal stability when using the two different interface designs. The co-contraction contributed to increased spinal load when using the unstable interface. It was concluded that handle or interface design and stability may influence spinal load and associated risk of musculoskeletal injury during manual materials tasks that involve pushing exertions.
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Affiliation(s)
- P J Lee
- Musculoskeletal Biomechanics Laboratories, Department of Engineering Science and Mechanics, School of Biomedical Engineering and Science, Virginia Polytechnic Institute and State University, 219 Norris Hall (0219), Blacksburg, VA 24061, USA
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28
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Lauritzen TZ, Miller KD. Different roles for simple-cell and complex-cell inhibition in V1. J Neurosci 2003; 23:10201-13. [PMID: 14614078 PMCID: PMC6741005] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023] Open
Abstract
Previously, we proposed a model of the circuitry underlying simple-cell responses in cat primary visual cortex (V1) layer 4. We argued that the ordered arrangement of lateral geniculate nucleus inputs to a simple cell must be supplemented by a component of feedforward inhibition that is untuned for orientation and responds to high temporal frequencies to explain the sharp contrast-invariant orientation tuning and low-pass temporal frequency tuning of simple cells. The temporal tuning also requires a significant NMDA component in geniculocortical synapses. Recent experiments have revealed cat V1 layer 4 inhibitory neurons with two distinct types of receptive fields (RFs): complex RFs with mixed ON/OFF responses lacking in orientation tuning, and simple RFs with normal, sharp-orientation tuning (although, some respond to all orientations). We show that complex inhibitory neurons can provide the inhibition needed to explain simple-cell response properties. Given this complex cell inhibition, antiphase or "push-pull" inhibition from tuned simple inhibitory neurons acts to sharpen spatial frequency tuning, lower responses to low temporal frequency stimuli, and increase the stability of cortical activity.
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Affiliation(s)
- Thomas Z Lauritzen
- Graduate Group in Biophysics, University of California, San Francisco, California 94143-0444, USA
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Troyer TW, Krukowski AE, Priebe NJ, Miller KD. Contrast-invariant orientation tuning in cat visual cortex: thalamocortical input tuning and correlation-based intracortical connectivity. J Neurosci 1998; 18:5908-27. [PMID: 9671678 PMCID: PMC6793055] [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] [Received: 01/30/1998] [Revised: 05/04/1998] [Accepted: 05/14/1998] [Indexed: 02/08/2023] Open
Abstract
The origin of orientation selectivity in visual cortical responses is a central problem for understanding cerebral cortical circuitry. In cats, many experiments suggest that orientation selectivity arises from the arrangement of lateral geniculate nucleus (LGN) afferents to layer 4 simple cells. However, this explanation is not sufficient to account for the contrast invariance of orientation tuning. To understand contrast invariance, we first characterize the input to cat simple cells generated by the oriented arrangement of LGN afferents. We demonstrate that it has two components: a spatial-phase-specific component (i.e., one that depends on receptive field spatial phase), which is tuned for orientation, and a phase-nonspecific component, which is untuned. Both components grow with contrast. Second, we show that a correlation-based intracortical circuit, in which connectivity between cell pairs is determined by the correlation of their LGN inputs, is sufficient to achieve well tuned, contrast-invariant orientation tuning. This circuit generates both spatially opponent, "antiphase" inhibition ("push-pull"), and spatially matched, "same-phase" excitation. The inhibition, if sufficiently strong, suppresses the untuned input component and sharpens responses to the tuned component at all contrasts. The excitation amplifies tuned responses. This circuit agrees with experimental evidence showing spatial opponency between, and similar orientation tuning of, the excitatory and inhibitory inputs received by a simple cell. Orientation tuning is primarily input driven, accounting for the observed invariance of tuning width after removal of intracortical synaptic input, as well as for the dependence of orientation tuning on stimulus spatial frequency. The model differs from previous push-pull models in requiring dominant rather than balanced inhibition and in predicting that a population of layer 4 inhibitory neurons should respond in a contrast-dependent manner to stimuli of all orientations, although their tuning width may be similar to that of excitatory neurons. The model demonstrates that fundamental response properties of cortical layer 4 can be explained by circuitry expected to develop under correlation-based rules of synaptic plasticity, and shows how such circuitry allows the cortex to distinguish stimulus intensity from stimulus form.
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Affiliation(s)
- T W Troyer
- Department of Psychiatry, University of California, San Francisco, California 94143-0444, USA
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