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Plasma cortisol and metabolite level profiles in two isogenic strains of common carp during confinement 总被引:3,自引:0,他引:3
A rapid increase in common carp Cyprinus carpio plasma cortisol levels was noted, in two experiments, after 30 mins of a 3 h net confinement, which was sustained while the fish were held in the nets. After release from the nets, cortisol levels returned to control values in 1 h. Plasma glucose and free fatty acid levels were elevated by the confinement. Glucose was increased after 30 min but returned to basal levels after 22 h of recovery while free fatty acids were not elevated until 3 h of confinement and remained high for the duration of the recovery period. After confinement for 3 h, plasma lactate levels were reduced and remained low for a further 1 h. No change in either plasma triglyceride or cholesterol levels were found during the study. Confinement had no effect on haematocrit levels but blood haemoglobin levels were reduced. In both experiments hypochloraemia occurred in response to confinement. However, values returned to pre-confinement levels 22 h after confinement. These results show that rearing isogenic carp strains, under identical conditions, results in a reproducable response to an acute stressor and that these carp respond in a similar manner to other teleost species. 相似文献
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Malin C. Rivers Steven P. Bachman Thomas R. Meagher Eimear Nic Lughadha Neil A. Brummitt 《Biodiversity and Conservation》2010,19(7):2071-2085
Despite the ecological and economic importance of plants, the majority of plant species and their conservation status are
still poorly known. Based on the limited knowledge we have of many plant species, especially those in the tropics, the use
of GIS techniques can give us estimates of the degree of population subdivision to be used in conservation assessments of
extinction risk. This paper evaluates how best to use the IUCN Red List Categories and Criteria to produce effective and consistent
estimates of subpopulation structure based on specimen data available in the herbaria around the world. We assessed population
structure through GIS-based analysis of the geographic distribution of collections, using herbarium specimen data for 11 species
of Delonix sensu lato. We used four methods: grid adjacency, circular buffer, Rapoport’s mean propinquity and alpha hull, to quantify population
structure according to the terms used in the IUCN Red List: numbers of subpopulations and locations, and degree of fragmentation.
Based on our findings, we recommend using the circular buffer method, as it is not dependent on collection density and allows
points to be added, subtracted and/or moved without altering the buffer placement. The ideal radius of the buffer is debatable;
however when dispersal characteristics of the species are unknown then a sliding scale, such as the 1/10th maximum inter-point
distance, is the preferred choice, as it is species-specific and not sensitive to collection density. Such quantitative measures
of population structure provide a rigorous means of applying IUCN criteria to a wide range of plant species that hitherto
were inaccessible to IUCN classification. 相似文献
24.
Rogério de S. Nóia Júnior Jean-Charles Deswarte Jean-Pierre Cohan Pierre Martre Marijn van der Velde Remi Lecerf Heidi Webber Frank Ewert Alex C. Ruane Gustavo A. Slafer Senthold Asseng 《Global Change Biology》2023,29(11):3130-3146
France suffered, in 2016, the most extreme wheat yield decline in recent history, with some districts losing 55% yield. To attribute causes, we combined the largest coherent detailed wheat field experimental dataset with statistical and crop model techniques, climate information, and yield physiology. The 2016 yield was composed of up to 40% fewer grains that were up to 30% lighter than expected across eight research stations in France. The flowering stage was affected by prolonged cloud cover and heavy rainfall when 31% of the loss in grain yield was incurred from reduced solar radiation and 19% from floret damage. Grain filling was also affected as 26% of grain yield loss was caused by soil anoxia, 11% by fungal foliar diseases, and 10% by ear blight. Compounding climate effects caused the extreme yield decline. The likelihood of these compound factors recurring under future climate change is estimated to change with a higher frequency of extremely low wheat yields. 相似文献
25.
James A. Franke Christoph Müller Sara Minoli Joshua Elliott Christian Folberth Charles Gardner Tobias Hank Roberto Cesar Izaurralde Jonas Jgermeyr Curtis D. Jones Wenfeng Liu Stefan Olin Thomas A.M. Pugh Alex C. Ruane Haynes Stephens Florian Zabel Elisabeth J. Moyer 《Global Change Biology》2022,28(1):167-181
Modern food production is spatially concentrated in global “breadbaskets.” A major unresolved question is whether these peak production regions will shift poleward as the climate warms, allowing some recovery of potential climate-related losses. While agricultural impacts studies to date have focused on currently cultivated land, the Global Gridded Crop Model Intercomparison Project (GGCMI) Phase 2 experiment allows us to assess changes in both yields and the location of peak productivity regions under warming. We examine crop responses under projected end of century warming using seven process-based models simulating five major crops (maize, rice, soybeans, and spring and winter wheat) with a variety of adaptation strategies. We find that in no-adaptation cases, when planting date and cultivar choices are held fixed, regions of peak production remain stationary and yield losses can be severe, since growing seasons contract strongly with warming. When adaptations in management practices are allowed (cultivars that retain growing season length under warming and modified planting dates), peak productivity zones shift poleward and yield losses are largely recovered. While most growing-zone shifts are ultimately limited by geography, breadbaskets studied here move poleward over 600 km on average by end of the century under RCP 8.5. These results suggest that agricultural impacts assessments can be strongly biased if restricted in spatial area or in the scope of adaptive behavior considered. Accurate evaluation of food security under climate change requires global modeling and careful treatment of adaptation strategies. 相似文献
26.
Refined Linkage Disequilibrium and Physical Mapping of the Gene Locus for X-Linked Dystonia–Parkinsonism (DYT3) 总被引:3,自引:0,他引:3
Andrea H. Nmeth Dagmar Nolte Eimear Dunne Stephan Niemann Markus Kostrzewa Usha Peters Eileen Fraser Elena Bochukova Robin Butler Julie Brown Roger D. Cox Elaine R. Levy Hans-Hilger Ropers Anthony P. Monaco Ulrich Müller 《Genomics》1999,60(3):320-329
X-linked dystonia-parkinsonism (XDP) is a recessive disorder characterized by generalized dystonia with some patients exhibiting parkinsonism. The disease gene, DYT3, is located between DXS453 (DXS993) and DXS559, and strongest linkage disequilibrium is found distal to DXS7117 and proximal to DXS559. We have isolated and analyzed four novel polymorphic markers between DXS7117 and DXS559 and, by haplotype analysis, have narrowed the candidate interval to <350 kb. A sequence-ready contig of 700 kb has been constructed spanning DXS7117 to DXS559 and is composed of 35 PACs, BACs, and cosmids. Nine genes and novel ESTs have been mapped into this contig, and mutations in the coding regions and intron-exon borders of two genes have been excluded as the cause of XDP. Several of the other genes and ESTs located within the contig code for proteins implicated in normal brain development and function and are candidates for DYT3. 相似文献
27.
Asynchronous demographic responses to Pleistocene climate change in Eastern Nearctic vertebrates 下载免费PDF全文
Frank T. Burbrink Yvonne L. Chan Edward A. Myers Sara Ruane Brian Tilston Smith Michael J. Hickerson 《Ecology letters》2016,19(12):1457-1467
Pleistocene climatic cycles altered species distributions in the Eastern Nearctic of North America, yet the degree of congruent demographic response to the Pleistocene among codistributed taxa remains unknown. We use a hierarchical approximate Bayesian computational approach to test if population sizes across lineages of snakes, lizards, turtles, mammals, birds, salamanders and frogs in this region expanded synchronously to Late Pleistocene climate changes. Expansion occurred in 75% of 74 lineages, and of these, population size trajectories across the community were partially synchronous, with coexpansion found in at least 50% of lineages in each taxonomic group. For those taxa expanding outside of these synchronous pulses, factors related to when they entered the community, ecological thresholds or biotic interactions likely condition their timing of response to Pleistocene climate change. Unified timing of population size change across communities in response to Pleistocene climate cycles is likely rare in North America. 相似文献
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Neil Brummitt Steven P. Bachman Elina Aletrari Helen Chadburn Janine Griffiths-Lee Maiko Lutz Justin Moat Malin C. Rivers Mindy M. Syfert Eimear M. Nic Lughadha 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2015,370(1662)
The IUCN Sampled Red List Index (SRLI) is a policy response by biodiversity scientists to the need to estimate trends in extinction risk of the world''s diminishing biological diversity. Assessments of plant species for the SRLI project rely predominantly on herbarium specimen data from natural history collections, in the overwhelming absence of accurate population data or detailed distribution maps for the vast majority of plant species. This creates difficulties in re-assessing these species so as to measure genuine changes in conservation status, which must be observed under the same Red List criteria in order to be distinguished from an increase in the knowledge available for that species, and thus re-calculate the SRLI. However, the same specimen data identify precise localities where threatened species have previously been collected and can be used to model species ranges and to target fieldwork in order to test specimen-based range estimates and collect population data for SRLI plant species. Here, we outline a strategy for prioritizing fieldwork efforts in order to apply a wider range of IUCN Red List criteria to assessments of plant species, or any taxa with detailed locality or natural history specimen data, to produce a more robust estimation of the SRLI. 相似文献