10 results on '"Lewis, Gavin"'
Search Results
2. The Role of Source‐Sink Dynamics in the Assessment of Risk to Nontarget Arthropods from the Use of Plant Protection Products.
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Lewis, Gavin, Dinter, Axel, Elston, Charlotte, Marx, Michael Thomas, Mayer, Christoph Julian, Neumann, Paul, Pilling, Ed, and Braaker, Sonja
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PLANT products , *PLANT protection , *RISK assessment , *ARTHROPODA , *ENVIRONMENTAL toxicology - Abstract
The concept of source‐sink dynamics as a potentially important component of metapopulation dynamics was introduced in the 1980s. The objective of the present review was to review the considerable body of work that has been developed, to consider its theoretical implications as well as to understand how source‐sink dynamics may manifest under field conditions in the specific case of nontarget arthropods in the agricultural environment. Our review concludes that metapopulation dynamics based on field observations are often far more complex than existing theoretical source‐sink models would indicate, because they are dependent on numerous population processes and influencing factors. The difficulty in identifying and measuring these factors likely explains why empirical studies assessing source‐sink dynamics are scarce. Furthermore, we highlight the importance of considering the spatial and temporal heterogeneity of agricultural landscapes when assessing the population dynamics of nontarget arthropods in the context of the risk from the use of plant protection products. A need is identified to further develop and thoroughly validate predictive population models, which can incorporate all factors relevant to a specific system. Once reliable predictive models for a number of representative nontarget arthropod species are available, they could provide a meaningful tool for refined risk evaluations (higher tier level risk assessment), addressing specific concerns identified at the initial evaluation stages (lower tier level risk assessment). Environ Toxicol Chem 2021;40:2667–2679. © 2021 ERM, FMC, Syngenta, Bayer AG, BASF SE, Corteva agriscience. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]
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- 2021
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3. Group 2 innate lymphoid cells are elevated and activated in chronic rhinosinusitis with nasal polyps.
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Poposki, Julie A., Klingler, Aiko I., Tan, Bruce K., Soroosh, Pejman, Banie, Homayon, Lewis, Gavin, Hulse, Kathryn E., Stevens, Whitney W., Peters, Anju T., Grammer, Leslie C., Schleimer, Robert P., Welch, Kevin C., Smith, Stephanie S., Conley, David B., Raviv, Joseph R., Karras, James G., Akbari, Omid, Kern, Robert C., and Kato, Atsushi
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LYMPHOID tissue ,NASAL polyps ,THYMIC stromal lymphopoietin ,CYTOKINES ,SINUSITIS - Abstract
Background Chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) is characterized by type 2 inflammation with high levels of Th2 cytokines. Although T helper cytokines are released from T cells, innate lymphoid cells (ILC) are also known to produce high levels of the same cytokines. However, the presence of various types of ILC in CRS is poorly understood. Objective The objective of this study was to fully characterize the presence of all ILC subsets in CRS and to identify phenotypical differences of group 2 ILC (ILC2) in CRSwNP compared to ILC2 from non-type 2 inflamed areas. Methods We investigated the presence of ILC subsets in peripheral blood mononuclear cells (PBMC) from healthy subjects, tonsil tissue, ethmoid tissue from control subjects and patients with non-polypoid CRS (CRSsNP) and CRSwNP, as well as nasal polyp (NP) tissue from CRSwNP by flow cytometry. Sorted ILC2 were cultured in the presence and absence of IL-33 and production of IL-5 and IL-13 was assessed by Luminex. Results We found that all ILC subsets were present in NP but ILC2 were dominant and significantly elevated compared to PBMC, tonsil, CRSsNP, and normal sinus tissue. We also found that inducible T-cell co-stimulator (ICOS) and side scatter were increased and CD127 was down-regulated in ILC2 from NP compared to blood or tonsil ILC2. Thymic stromal lymphopoietin, IL-7, and IL-33 were able to down-regulate expression of CD127 and increase side scatter in blood ILC2. Furthermore, sorted NP ILC2 but not blood ILC2 spontaneously released type 2 cytokines including IL-5 and IL-13. Conclusions and Clinical Relevance These results suggest that ILC2 are not only elevated but also activated in CRSwNP in vivo and that ILC2 may play important roles in the type 2 inflammation in CRSwNP. [ABSTRACT FROM AUTHOR]
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- 2017
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4. Initial recommendations for higher-tier risk assessment protocols for bumble bees, Bombus spp. (Hymenoptera: Apidae).
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Cabrera, Ana R, Almanza, Maria Teresa, Cutler, G Christopher, Fischer, David L, Hinarejos, Silvia, Lewis, Gavin, Nigro, Daniel, Olmstead, Allen, Overmyer, Jay, Potter, Daniel A, Raine, Nigel E, Stanley‐Stahr, Cory, Thompson, Helen, and van der Steen, Jozef
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BUMBLEBEES ,INSECT behavior ,BEE ecology ,INSECT ecology ,APPLICATION of pesticides ,PHYSIOLOGY - Abstract
ABSTRACT Global declines of bumble bees and other pollinator populations are of concern because of their critical role for crop production and maintenance of wild plant biodiversity. Although the consensus among scientists is that the interaction of many factors, including habitat loss, forage scarcity, diseases, parasites, and pesticides, potentially plays a role in causing these declines, pesticides have received considerable attention and scrutiny. In response, regulatory agencies have introduced more stringent pollinator testing requirements for registration and reregistration of pesticides, to ensure that the risks to pollinators are minimized. In this context, guidelines for testing bumble bees ( Bombus spp.) in regulatory studies are not yet available, and a pressing need exists to develop suitable protocols for routine higher-tier studies with these non- Apis sp., social bees. To meet this need, Bayer CropScience LP, Syngenta Crop Protection LLC US, and Valent USA. Corporation organized a workshop bringing together a group of global experts on bumble bee behavior, ecology, and ecotoxicology to discuss and develop draft protocols for both semi-field (Tier II) and field (Tier III) studies. The workshop was held May 8-9, 2014, at the Bayer Bee Care Center, North Carolina, USA. The participants represented academic, consulting, and industry scientists from Europe, Canada, the United States, and Brazil. The workshop identified a clear protection goal and generated proposals for basic experimental designs, relevant measurements, and endpoints for both semifield (tunnel) and field tests. These initial recommendations are intended to form the basis of discussions to help advance the development of appropriate protocol guidelines. Integr Environ Assess Manag 2016;12:222-229. © 2015 The Authors. Integrated Environmental Assessment and Management Published by SETAC [ABSTRACT FROM AUTHOR]
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- 2016
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5. Improving Safety in Catheter Ablation for Atrial Fibrillation: A Prospective Study of the Use of Ultrasound to Guide Vascular Access.
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WYNN, GARETH J., HAQ, IRAM, HUNG, JOHN, BONNETT, LAURA J., LEWIS, GAVIN, WEBBER, MATTHEW, WAKTARE, JOHAN E.P., MODI, SIMON, SNOWDON, RICHARD L., HALL, MARK C.S., TODD, DERICK M., and GUPTA, DHIRAJ
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PREVENTION of surgical complications ,CATHETER ablation ,ULTRASONIC imaging ,ATRIAL fibrillation ,CHI-squared test ,CONFIDENCE intervals ,HEMORRHAGE ,LONGITUDINAL method ,PATIENT safety ,QUALITY assurance ,QUESTIONNAIRES ,REGRESSION analysis ,RESEARCH funding ,SURGICAL complications ,T-test (Statistics) ,U-statistics ,DATA analysis software ,DESCRIPTIVE statistics ,ODDS ratio - Abstract
Vascular Ultrasound for AFA Introduction The most frequent complications of AF ablation (AFA) are related to vascular access, but there is little evidence as to how these can be minimized. Methods Consecutive patients undergoing AFA at a high-volume center received either standard care (Group S) or routine ultrasound-guided vascular access (Group U). Vascular complications were assessed before hospital discharge and by means of postal questionnaire 1 month later. Outcome measures were BARC 2+ bleeding complications, postprocedural pain, and prolonged bruising. Results Patients in Group S (n = 146) and U (n = 163) were well matched at baseline. Follow-up questionnaires were received from 92.6%. Patients in Group U were significantly less likely to have a BARC 2+ bleed, 10.4% versus 19.9% P = 0.02, were less likely to suffer groin pain after discharge (27.1% vs. 42.8%; P = 0.006) and were less likely to experience prolonged local bruising (21.5% vs. 40.4%; P = 0.001). Multivariable logistic regression analysis revealed a significant association of vascular complications with nonultrasound guided access (OR 3.12 95%CI 1.54-5.34; P = 0.003) and increasing age (OR 1.05 95%CI 1.01-1.09; P = 0.02). Conclusion Routine use of ultrasound-guided vascular access for AFA is associated with a significant reduction in bleeding complications, postprocedural pain, and prolonged bruising when compared to standard care. [ABSTRACT FROM AUTHOR]
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- 2014
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6. Guidance for the assessment of risks to bees from the use of plant protection products under the framework of Council Directive 91/414 and Regulation 1107/2009.
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Alix, Anne and Lewis, Gavin
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PLANT protection , *SYSTEMIC insecticides , *HONEYBEES , *ANIMAL ecology , *RISK assessment of pesticides , *APPLICATION of pesticides , *PEST control - Abstract
About 15 years have passed since the implementation of Directive 91/414/EEC and the regulatory framework with regard to pesticide use and environmental protection aims, as well as the plant protection techniques involving pesticides, have evolved over this period. In the case of honey bees, further developments and updates with regards to larval testing have been undertaken. Experimental protocols for semi-field and field testing have been reviewed in detail. Finally, a dedicated risk assessment scheme has been developed for seed coating and soil applications that involve systemic compounds. A revision of the original EPPO Standards: the Risk Assessment Scheme PP 3/10(2) Honeybees and the test guidelines PP1/170 (3) Side-effects on honeybees has thus been undertaken in order to benefit from these improvements. This paper aims to provide the details of the reasoning on which the revised risk assessment scheme relies as well as providing the necessary references to the data which have been reviewed in the context of this revision. [ABSTRACT FROM AUTHOR]
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- 2010
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7. AN ECOLOGICAL RISK ASSESSMENT FOR TRICLOSAN IN THE TERRESTRIAL ENVIRONMENT.
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Reiss, Richard, Lewis, Gavin, and Griffin, John
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PLANT-soil relationships , *SOIL microbiology , *MICROORGANISMS , *SEWAGE purification , *WATER utilities , *WATER quality management , *INVESTMENT analysis , *WASTEWATER treatment - Abstract
Triclosan (2,4,4′-trichloro-2′-hydroxydiphenyl ether) is a broad-spectrum bactericide used throughout North America and Europe for a variety of antimicrobial functions. This paper addresses the risk to terrestrial organisms from several potential exposure pathways: Exposure experienced by earthworms, terrestrial plants, and soil microorganisms as the result of the use of sewage sludge containing triclosan as an agricultural soil amendment; secondary exposure by birds and mammals from consumption of earthworms that have been exposed to triclosan in soil; and secondary exposure by birds and mammals from consumption of fish exposed to triclosan as the result of wastewater treatment discharges. The assessment found satisfactory margins of safety for plants, earthworms, birds, fish, mammals, and soil microorganisms. The lowest margins of safety were for nontarget plants (100 for the typical scenario and 8 for the upper-bound scenario). However, these margins of safety are still above the European Union (EU) recommended fivefold assessment value for nontarget plants and are based on cucumber results from a vegetative vigor study conducted in quartz sand that is of limited relevance for risk assessment. In a pre-emergence study conducted in a more relevant soil (sandy loam), cucumbers showed no response to triclosan at the highest dose tested (1,000 μg/kg). A recent study provides limited field measurements of soil and earthworm concentrations. While that study finds higher soil and earthworm concentrations than were estimated in the present study, even these higher concentrations do not indicate significant risks. [ABSTRACT FROM AUTHOR]
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- 2009
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8. Non-redundant function of the MEK5–ERK5 pathway in thymocyte apoptosis.
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Sohn, Sue J., Lewis, Gavin M., and Winoto, Astar
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MITOGEN-activated protein kinases , *APOPTOSIS , *T cells , *PROTEIN kinases , *HOMOLOGY (Biology) - Abstract
The mitogen-activated protein kinases (MAPKs) ERK1/2, p38, and JNK are thought to determine survival-versus-death fate in developing thymocytes. However, this view was challenged by studies using ‘MEK1-ERK1/2-specific’ pharmacological inhibitors, which block both positive and negative selection. Recently, these inhibitors were also shown to affect MEK5, an upstream activator of ERK5, another class of MAPK with homology to ERK1/2. To define the contribution of the MEK5–ERK5 pathway in T-cell development, we retrovirally expressed dominant-negative or constitutively activated form of MEK5 to inhibit or activate the MEK5–ERK5 pathway. We demonstrate that MEK5 regulates apoptosis of developing thymocytes but has no function in positive selection. ERK5 activity correlates with the levels of Nur77 family members but not that of Bim, two effector pathways of thymocyte apoptosis. These results illustrate the critical involvement of the MEK5–ERK5 pathway in thymocyte development distinct from that of ERK1/2 and highlight the importance of the MAPK network in mediating differential effects pertaining to T-cell differentiation and apoptosis. [ABSTRACT FROM AUTHOR]
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- 2008
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9. In Focus: Pesticides and honeybees - the, work of the ICP-BR Bee Protection Group Editorial.
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Lewis, Gavin, Thompson, Helen, and Smagghe, Guy
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BEES ,PEST control ,PESTICIDES ,MANAGEMENT ,MANAGEMENT science - Abstract
The article discusses the pest management science focusing on the protection group, International Commission for Plant Bee Relationships (ICP-BR). The group held their first meeting in 1980 and has since established expert forums for addressing risk to pesticides. The group actively looks into the issues affecting bee health in various EU countries and also in North America.
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- 2007
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10. The role of evaporite mobility in modifying subsidence patterns during normal fault growth and linkage, Halten Terrace, Mid-Norway.
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Richardson, Nick J., Underhill, John R., and Lewis, Gavin
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EVAPORITES ,GEOLOGIC faults ,RIFTS (Geology) ,STRUCTURAL geology ,PHYSICAL geology ,LAND subsidence - Abstract
Well-calibrated seismic interpretation in the Halten Terrace of Mid-Norway demonstrates the important role that structural feedback between normal fault growth and evaporite mobility has for depocentre development during syn-rift deposition of the Jurassic–Early Cretaceous Viking and Fangst Groups. While the main rift phase reactivated pre-existing structural trends, and initiated new extensional structures, a Triassic evaporite interval decouples the supra-salt cover strata from the underlying basement, causing the development of two separate fault populations, one in the cover and the other confined to the pre-salt basement.Detailed displacement–length analyses of both cover and basement fault arrays, combined with mapping of the component parts of the syn-rift interval, have been used to reveal the spatial and temporal evolution of normal fault segments and sediment depocentres within the Halten Terrace area. Significantly, the results highlight important differences with traditional models of normal fault-controlled subsidence, including those from parts of the North Sea where salt is absent. It can now be shown that evaporite mobility is intimately linked to the along-strike displacement variations of these cover and basement faults. The evaporites passively move beneath the cover in response to the extension, such that the evaporite thickness becomes greatest adjacent to regions of high fault displacement. The consequent evaporite swells can become large enough to have pronounced palaeobathymetric relief in hangingwall locations, associated with fault displacementmaxima– the exact opposite situation to that predicted by traditional models of normal fault growth. Evaporite movement from previous extension also affects the displacement–length relationships of subsequently nucleated or reactivated faults. Evaporite withdrawal, on the other hand, tends to be a later-stage feature associated with the high stress regions around the propagating tips of normal faults or their coeval hangingwall release faults. The results indicate the important effect of, and structural feedback caused by, syn-rift evaporite mobility in heavily modifying subsidence patterns produced by normal fault array evolution. Despite their departure from published models, the results provide a new, generic framework within which to interpret extensional fault and depocentre development and evolution in areas in which mobile evaporites exist. [ABSTRACT FROM AUTHOR]
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- 2005
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