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81.
To improve the welfare of nonhuman animals under professional care, zoological institutions are continuously utilizing new methods to identify factors that lead to optimal welfare. Comparative methods have historically been used in the field of evolutionary biology but are increasingly being applied in the field of animal welfare. In the current study, data were obtained from direct behavioral observation and institutional records representing 80 individual animals from 34 different species of the order Carnivora. Data were examined to determine if a variety of natural history and animal management factors impacted the welfare of animals in zoological institutions. Output variables indicating welfare status included behavioral diversity, pacing, offspring production, and infant mortality. Results suggested that generalist species have higher behavioral diversity and offspring production in zoos compared with their specialist counterparts. In addition, increased minimum distance from the public decreased pacing and increased offspring production, while increased maximum distance from the public and large enclosure size decreased infant mortality. These results have implications for future exhibit design or renovation, as well as management practices and priorities for future research.  相似文献   
82.
Climate change can affect marine and estuarine fish via alterations to their distributions, abundances, sizes, physiology and ecological interactions, threatening the provision of ecosystem goods and services. While we have an emerging understanding of such ecological impacts to fish, we know little about the potential influence of climate change on the provision of nutritional seafood to sustain human populations. In particular, the quantity, quality and/or taste of seafood may be altered by future environmental changes with implications for the economic viability of fisheries. In an orthogonal mesocosm experiment, we tested the influence of near‐future ocean warming and acidification on the growth, health and seafood quality of a recreationally and commercially important fish, yellowfin bream (Acanthopagrus australis). The growth of yellowfin bream significantly increased under near‐future temperature conditions (but not acidification), with little change in health (blood glucose and haematocrit) or tissue biochemistry and nutritional properties (fatty acids, lipids, macro‐ and micronutrients, moisture, ash and total N). Yellowfin bream appear to be highly resilient to predicted near‐future ocean climate change, which might be facilitated by their wide spatio‐temporal distribution across habitats and broad diet. Moreover, an increase in growth, but little change in tissue quality, suggests that near‐future ocean conditions will benefit fisheries and fishers that target yellowfin bream. The data reiterate the inherent resilience of yellowfin bream as an evolutionary consequence of their euryhaline status in often environmentally challenging habitats and imply their sustainable and viable fisheries into the future. We contend that widely distributed species that span large geographic areas and habitats can be “climate winners” by being resilient to the negative direct impacts of near‐future oceanic and estuarine climate change.  相似文献   
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84.
Quantitative models play an increasing role in exploring the impact of global change on biodiversity. To win credibility and trust, they need validating. We show how expert knowledge can be used to assess a large number of empirical species niche models constructed for the British vascular plant and bryophyte flora. Key outcomes were (a) scored assessments of each modeled species and niche axis combination, (b) guidance on models needing further development, (c) exploration of the trade‐off between presenting more complex model summaries, which could lead to more thorough validation, versus the longer time these take to evaluate, (d) quantification of the internal consistency of expert opinion based on comparison of assessment scores made on a random subset of models evaluated by both experts. Overall, the experts assessed 39% of species and niche axis combinations to be “poor” and 61% to show a degree of reliability split between “moderate” (30%), “good” (25%), and “excellent” (6%). The two experts agreed in only 43% of cases, reaching greater consensus about poorer models and disagreeing most about models rated as better by either expert. This low agreement rate suggests that a greater number of experts is required to produce reliable assessments and to more fully understand the reasons underlying lack of consensus. While area under curve (AUC) statistics showed generally very good ability of the models to predict random hold‐out samples of the data, there was no correspondence between these and the scores given by the experts and no apparent correlation between AUC and species prevalence. Crowd‐sourcing further assessments by allowing web‐based access to model fits is an obvious next step. To this end, we developed an online application for inspecting and evaluating the fit of each niche surface to its training data.  相似文献   
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Chang SB  Anderson LK  Sherman JD  Royer SM  Stack SM 《Genetics》2007,176(4):2131-2138
Predicting the chromosomal location of mapped markers has been difficult because linkage maps do not reveal differences in crossover frequencies along the physical structure of chromosomes. Here we combine a physical crossover map based on the distribution of recombination nodules (RNs) on Solanum lycopersicum (tomato) synaptonemal complex 1 with a molecular genetic linkage map from the interspecific hybrid S. lycopersicum x S. pennellii to predict the physical locations of 17 mapped loci on tomato pachytene chromosome 1. Except for one marker located in heterochromatin, the predicted locations agree well with the observed locations determined by fluorescence in situ hybridization. One advantage of this approach is that once the RN distribution has been determined, the chromosomal location of any mapped locus (current or future) can be predicted with a high level of confidence.  相似文献   
87.
Recently, a novel 87-amino acid influenza A virus protein with proapoptotic properties, PB1-F2, has been reported that originates from an alternative reading frame in the PB1 polymerase gene and is encoded in most known human influenza A virus isolates. Here we characterize the molecular structure of a biologically active synthetic version of the protein (sPB1-F2). Western blot analysis, chemical cross-linking, and NMR spectroscopy afforded direct evidence of the inherent tendency of sPB1-F2 to undergo oligomerization mediated by two distinct domains located in the N and C termini, respectively. CD and (1)H NMR spectroscopic analyses indicate that the stability of structured regions in the molecule clearly depends upon the hydrophobicity of the solvent. In aqueous solutions, the behavior of sPB1-F2 is typical of a largely random coil peptide that, however, adopts alpha-helical structure upon the addition of membrane mimetics. (1)H NMR analysis of three overlapping peptides afforded, for the first time, direct experimental evidence of the presence of a C-terminal region with strong alpha-helical propensity comprising amino acid residues Ile(55)-Lys(85) connected via an essentially random coil structure to a much weaker helix-like region, located in the N terminus between residues Trp(9) and Lys(20). The C-terminal helix is not a true amphipathic helix and is more compact than previously predicted. It corresponds to a positively charged region previously shown to include the mitochondrial targeting sequence of PB1-F2. The consequences of the strong oligomerization and helical propensities of the molecule are discussed and used to formulate a hypothetical model of its interaction with the mitochondrial membrane.  相似文献   
88.
Highly purified fractions of bone extracts capable of inducing ectopic bone formation have been reported to contain peptides corresponding to the mature active regions of the TGF-beta-like bone morphogenetic proteins (BMPs) 2-7, and to the prodomain region of the metalloproteinase BMP1. Co-purification of BMPs 2-7 with BMP1 prodomain sequences through the multiple biochemical steps used in these previous reports has suggested the possibility of interactions between the BMP1 prodomain and BMPs 2-7. Here we demonstrate that the BMP1 prodomain binds BMPs 2 and 4 with high specificity and with a KD of approximately 11 nM, in the physiological range. It is further demonstrated that the BMP1 prodomain is capable of modulating signaling by BMPs 2 and 4 in vitro and in vivo, and that endogenous BMP1 prodomain-BMP4 complexes exist in cell culture media and in tissues.  相似文献   
89.
Fragile X syndrome (FX), the most common heritable cause of mental retardation and autism, is a developmental disorder characterized by physical, cognitive, and behavioral deficits. FX results from a trinucleotide expansion mutation in the fmr1 gene that reduces levels of fragile X mental retardation protein (FMRP). Although research efforts have focused on FMRP's impact on mGluR signaling, how the loss of FMRP leads to the individual symptoms of FX is not known. Previous studies on human FX blood cells revealed alterations in the cyclic adenosine 3', 5'-monophosphate (cAMP) cascade. We tested the hypothesis that cAMP signaling is altered in the FX nervous system using three different model systems. Induced levels of cAMP in platelets and in brains of fmr1 knockout mice are substantially reduced. Cyclic AMP induction is also significantly reduced in human FX neural cells. Furthermore, cAMP production is decreased in the heads of FX Drosophila and this defect can be rescued by reintroduction of the dfmr gene. Our results indicate that a robust defect in cAMP production in FX is conserved across species and suggest that cAMP metabolism may serve as a useful biomarker in the human disease population. Reduced cAMP induction has implications for the underlying causes of FX and autism spectrum disorders. Pharmacological agents known to modulate the cAMP cascade may be therapeutic in FX patients and can be tested in these models, thus supplementing current efforts centered on mGluR signaling.  相似文献   
90.
In recognition, discriminators use sensory information to make decisions. For example, honeybee (Apis mellifera) entrance guards discriminate between nest-mates and intruders by comparing their odours with a template of the colony odour. Comb wax plays a major role in honeybee recognition. We measured the rejection rates of nest-mate and non-nest-mate worker bees by entrance guards before and after a unidirectional transfer of wax comb from a 'comb donor' hive to a 'comb receiver' hive. Our results showed a significant effect that occurred in one direction. Guards in the comb receiver hive became more accepting of non-nest-mates from the comb donor hive (rejection decreased from 70 to 47%); however, guards in the comb donor hive did not become more accepting of bees from the comb receiver hive. These data strongly support the hypothesis that the transfer of wax comb increases the acceptance of non-nest-mates not by changing the odour of the bees, but by changing the template used by guards.  相似文献   
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