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21.
Edgar A. van der Grift Rodney van der Ree Lenore Fahrig Scott Findlay Jeff Houlahan Jochen A. G. Jaeger Nina Klar L. Francisco Madriñan Leif Olson 《Biodiversity and Conservation》2013,22(2):425-448
The last 20 years have seen a dramatic increase in efforts to mitigate the negative effects of roads and traffic on wildlife, including fencing to prevent wildlife-vehicle collisions and wildlife crossing structures to facilitate landscape connectivity. While not necessarily explicitly articulated, the fundamental drivers behind road mitigation are human safety, animal welfare, and/or wildlife conservation. Concomitant with the increased effort to mitigate has been a focus on evaluating road mitigation. So far, research has mainly focussed on assessing the use of wildlife crossing structures, demonstrating that a broad range of species use them. However, this research has done little to address the question of the effectiveness of crossing structures, because use of a wildlife crossing structure does not necessarily equate to its effectiveness. The paucity of studies directly examining the effectiveness of crossing structures is exacerbated by the fact that such studies are often poorly designed, which limits the level of inference that can be made. Without well performed evaluations of the effectiveness of road mitigation measures, we may endanger the viability of wildlife populations and inefficiently use financial resources by installing structures that are not as effective as we think they are. In this paper we outline the essential elements of a good experimental design for such assessments and prioritize the parameters to be measured. The framework we propose will facilitate collaboration between road agencies and scientists to undertake research programs that fully evaluate effectiveness of road mitigation measures. We discuss the added value of road mitigation evaluations for policy makers and transportation agencies and provide recommendations on how to incorporate such evaluations in road planning practices. 相似文献
22.
This systematic review examines effects of surface texture on marine biofouling and characterizes key research methodologies. Seventy-five published articles met selection criteria for qualitative analysis; experimental data from 36 underwent quantitative meta-analysis. Most studies investigated fouling mechanisms and antifouling performance only in laboratory assays with one to several test species. Textures were almost exclusively a single layer of regularly arranged geometric features rather than complex hierarchical or irregular designs. Textures in general had no effect or an inconclusive effect on fouling in 46% of cases. However, effective textures more often decreased (35%) rather than increased (19%) fouling. Complex designs were more effective against fouling (51%) than were regular geometric features (32%). Ratios of feature height, width, or pitch to organism body length were significant influences. The authors recommend further research on promising complex and hierarchical texture designs with more test species, as well as field studies to ground-truth laboratory results. 相似文献
23.
Michelle L. Gatton Nakul Chitnis Thomas Churcher Martin J. Donnelly Azra C. Ghani H. Charles J. Godfray Fred Gould Ian Hastings John Marshall Hilary Ranson Mark Rowland Jeff Shaman Steve W. Lindsay 《Evolution; international journal of organic evolution》2013,67(4):1218-1230
Over the past decade the use of long‐lasting insecticidal nets (LLINs), in combination with improved drug therapies, indoor residual spraying (IRS), and better health infrastructure, has helped reduce malaria in many African countries for the first time in a generation. However, insecticide resistance in the vector is an evolving threat to these gains. We review emerging and historical data on behavioral resistance in response to LLINs and IRS. Overall the current literature suggests behavioral and species changes may be emerging, but the data are sparse and, at times unconvincing. However, preliminary modeling has demonstrated that behavioral resistance could have significant impacts on the effectiveness of malaria control. We propose seven recommendations to improve understanding of resistance in malaria vectors. Determining the public health impact of physiological and behavioral insecticide resistance is an urgent priority if we are to maintain the significant gains made in reducing malaria morbidity and mortality. 相似文献
24.
Horton R Gibson R Coggill P Miretti M Allcock RJ Almeida J Forbes S Gilbert JG Halls K Harrow JL Hart E Howe K Jackson DK Palmer S Roberts AN Sims S Stewart CA Traherne JA Trevanion S Wilming L Rogers J de Jong PJ Elliott JF Sawcer S Todd JA Trowsdale J Beck S 《Immunogenetics》2008,60(1):1-18
The human major histocompatibility complex (MHC) is contained within about 4 Mb on the short arm of chromosome 6 and is recognised
as the most variable region in the human genome. The primary aim of the MHC Haplotype Project was to provide a comprehensively
annotated reference sequence of a single, human leukocyte antigen-homozygous MHC haplotype and to use it as a basis against
which variations could be assessed from seven other similarly homozygous cell lines, representative of the most common MHC
haplotypes in the European population. Comparison of the haplotype sequences, including four haplotypes not previously analysed,
resulted in the identification of >44,000 variations, both substitutions and indels (insertions and deletions), which have
been submitted to the dbSNP database. The gene annotation uncovered haplotype-specific differences and confirmed the presence
of more than 300 loci, including over 160 protein-coding genes. Combined analysis of the variation and annotation datasets
revealed 122 gene loci with coding substitutions of which 97 were non-synonymous. The haplotype (A3-B7-DR15; PGF cell line)
designated as the new MHC reference sequence, has been incorporated into the human genome assembly (NCBI35 and subsequent
builds), and constitutes the largest single-haplotype sequence of the human genome to date. The extensive variation and annotation
data derived from the analysis of seven further haplotypes have been made publicly available and provide a framework and resource
for future association studies of all MHC-associated diseases and transplant medicine.
Horton and Gibson contributed equally to this work. 相似文献
25.
Laura H. Graham Jeff Bolling Gary Miller Nancy Pratt‐Hawkes Sharon Joseph 《Zoo biology》2002,21(4):403-408
Circulating patterns of progesterone and luteinizing hormone (LH) in the elephant have been well characterized, and routine monitoring of these hormones is now viewed as a valuable tool for making informed decisions about the reproductive management of elephants in captivity. Currently, LH monitoring in elephants is done with radio‐immunoassays (RIAs); unfortunately, the use of radioactive materials in RIAs limits their application to institutions with laboratory facilities equipped for the storage and disposal of radioactive waste. Enzyme‐immunoassays (EIAs) offer an inexpensive and more zoo‐friendly alternative to RIA. This work reports on an EIA capable of quantifying circulating LH in African elephants. The EIA employs a biotin label and microtiter plates coated with goat anti‐mouse gamma globulin. LH surges in African elephants (n=3) increased fivefold over baseline concentrations (1.00±0.1 ng/ml vs. 0.2±0.1 ng/ml) and occurred 19.3±0.2 days apart. Ovulatory LH surges were associated with an increase in serum progestogens from 4.8±0.4 ng/ml to 11.7±0.4 ng/ml. The ability to quantify reproductive hormones in elephants via EIA is an important step in the process of making endocrine monitoring more accessible to zoos housing these species. Zoo Biol 21:403–408, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
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27.
Keng Po Lai Xiao Lin Nathan Tam Jeff Cheuk Hin Ho Marty Kwok-Shing Wong Jie Gu Ting Fung Chan William Ka Fai Tse 《Environmental microbiology》2020,22(9):3784-3802
Alteration of the gut microbiota plays an important role in animal health and metabolic diseases. However, little is known with respect to the influence of environmental osmolality on the gut microbial community. The aim of the current study was to determine whether the reduction in salinity affects the gut microbiota and identify its potential role in salinity acclimation. Using Oryzias melastigma as a model organism to perform progressive hypotonic transfer experiments, we evaluated three conditions: seawater control (SW), SW to 50% sea water transfer (SFW) and SW to SFW to freshwater transfer (FW). Our results showed that the SFW and FW transfer groups contained higher operational taxonomic unit microbiota diversities. The dominant bacteria in all conditions constituted the phylum Proteobacteria, with the majority in the SW and SFW transfer gut comprising Vibrio at the genus level, whereas this population was replaced by Pseudomonas in the FW transfer gut. Furthermore, our data revealed that the FW transfer gut microbiota exhibited a reduced renin–angiotensin system, which is important in SW acclimation. In addition, induced detoxification and immune mechanisms were found in the FW transfer gut microbiota. The shift of the bacteria community in different osmolality environments indicated possible roles of bacteria in facilitating host acclimation. 相似文献
28.
Amy E. Zanne Kessy Abarenkov Michelle E. Afkhami Carlos A. Aguilar‐Trigueros Scott Bates Jennifer M. Bhatnagar Posy E. Busby Natalie Christian William K. Cornwell Thomas W. Crowther Habacuc Flores‐Moreno Dimitrios Floudas Romina Gazis David Hibbett Peter Kennedy Daniel L. Lindner Daniel S. Maynard Amy M. Milo Rolf Henrik Nilsson Jeff Powell Mark Schildhauer Jonathan Schilling Kathleen K. Treseder 《Biological reviews of the Cambridge Philosophical Society》2020,95(2):409-433
Fungi play many essential roles in ecosystems. They facilitate plant access to nutrients and water, serve as decay agents that cycle carbon and nutrients through the soil, water and atmosphere, and are major regulators of macro‐organismal populations. Although technological advances are improving the detection and identification of fungi, there still exist key gaps in our ecological knowledge of this kingdom, especially related to function . Trait‐based approaches have been instrumental in strengthening our understanding of plant functional ecology and, as such, provide excellent models for deepening our understanding of fungal functional ecology in ways that complement insights gained from traditional and ‐omics‐based techniques. In this review, we synthesize current knowledge of fungal functional ecology, taxonomy and systematics and introduce a novel database of fungal functional traits (FunFun). FunFun is built to interface with other databases to explore and predict how fungal functional diversity varies by taxonomy, guild, and other evolutionary or ecological grouping variables. To highlight how a quantitative trait‐based approach can provide new insights, we describe multiple targeted examples and end by suggesting next steps in the rapidly growing field of fungal functional ecology. 相似文献
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