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71.
Evidence is accumulating that species' responses to climate changes are best predicted by modelling the interaction of physiological limits, biotic processes and the effects of dispersal‐limitation. Using commercially harvested blacklip (Haliotis rubra) and greenlip abalone (Haliotis laevigata) as case studies, we determine the relative importance of accounting for interactions among physiology, metapopulation dynamics and exploitation in predictions of range (geographical occupancy) and abundance (spatially explicit density) under various climate change scenarios. Traditional correlative ecological niche models (ENM) predict that climate change will benefit the commercial exploitation of abalone by promoting increased abundances without any reduction in range size. However, models that account simultaneously for demographic processes and physiological responses to climate‐related factors result in future (and present) estimates of area of occupancy (AOO) and abundance that differ from those generated by ENMs alone. Range expansion and population growth are unlikely for blacklip abalone because of important interactions between climate‐dependent mortality and metapopulation processes; in contrast, greenlip abalone should increase in abundance despite a contraction in AOO. The strongly non‐linear relationship between abalone population size and AOO has important ramifications for the use of ENM predictions that rely on metrics describing change in habitat area as proxies for extinction risk. These results show that predicting species' responses to climate change often require physiological information to understand climatic range determinants, and a metapopulation model that can make full use of this data to more realistically account for processes such as local extirpation, demographic rescue, source‐sink dynamics and dispersal‐limitation.  相似文献   
72.
Sea‐level rise (SLR) is a projected consequence of global climate change that will result in complex changes in coastal ecosystems. These changes will cause transitions among coastal habitat types, which will be compounded by human‐made barriers to the gradual inland migration of these habitat types. The effect of these changes on the future viability of coastal species will depend on the habitat requirements and population dynamics of these species. Thus, realistic assessments of the impact of SLR require linking geomorphological models with habitat and population models. In this study, we implemented a framework that allows this linkage, and demonstrated its feasibility to assess the effect of SLR on the viability of the Snowy Plover population in Florida. The results indicate that SLR will cause a decline in suitable habitat and carrying capacity for this species, and an increase in the risk of its extinction and decline. The model projected that the population size will decline faster than the area of habitat or carrying capacity, demonstrating the necessity of incorporating population dynamics in assessing the impacts of SLR on coastal species. The results were most sensitive to uncertainties in survival rate and fecundity, and suggested that future studies on this species should focus on the average and variability of these demographic rates and their dependence on population density. The effect of SLR on this species’ viability was qualitatively similar with most alternative models that used the extreme values of each uncertain parameter, indicating that the results are robust to uncertainties in the model.  相似文献   
73.
In this study, nisin producer Lactococcus lactis strains displaying cell surface chitin-binding domain (ChBD) and capable of immobilizing to chitin flakes were constructed. To obtain ChBD-based cell immobilization, Usp45 signal sequence with ChBD of chitinase A1 enzyme from Bacillus circulans was fused with different lengths of PrtP (153, 344, and 800 aa) or AcmA (242 aa) anchors derived from L. lactis. According to the whole cell ELISA analysis, ChBD was successfully expressed on the surface of L. lactis cells. Scanning electron microscope observations supported the conclusion of the binding analysis that L. lactis cells expressing the ChBD with long PrtP anchor (800 aa) did bind to chitin surfaces more efficiently than cells with the other ChBD anchors. The attained binding affinity of nisin producers for chitin flakes retained them in the fermentation during medium changes and enabled storage for sequential productions. Initial nisin production was stably maintained with many cycles. These results demonstrate that an efficient immobilization of L. lactis cells to chitin is possible for industrial scale repeated cycle or continuous nisin fermentation.  相似文献   
74.
Sulfamides represent an important class of biologically active compounds. A series of novel sulfamides were synthesized from 1-aminoindanes, 1-aminotetralin, 2-aminoindanes and 2-aminotetralin via the reactions of free amines, benzyl alcohol and chlorosulfonyl isocyanate (CSI) followed by hydrogenolysis of the obtained sulfamoylcarbamates. Carbonic anhydrase (CA, EC 4.2.1.1) inhibitory effects of the new sulfamides have been investigated. The human (h) isozymes hCA I and hCA II have been investigated in this study by using an esterase assay with 4-nitrophenyl acetate as substrate. The new sulfamides showed inhibition constants in the micro–submicromolar range, with one compound (N-(indane-1-yl)sulfamide) showing a Ki of 0.45 μM against hCA I and of 1.07 μM against hCA II.  相似文献   
75.
The probiotic characteristics of Lactobacillus brevis BG18 and Lb. plantarum BG33, isolated from traditional Turkish Tulum cheese were assessed. These two bacteriocinproducer strains exhibited good probiotic characteristics such as resistance in media containing 0.3% bile salt, pepsin (3 mg mL?1), and pancreatine (1 mg mL?1) as well as acid resistance at pH 2. They were also adhered to Caco-2 epithelial cells in a manner comparable to Escherichia coli LMG3083 (ETEC) and Salmonella Typhimurium SL1344. The strains produced a heat-stable antimicrobial compound that was shown to be proteinaceous in nature, and therefore, referred to as bacteriocins. The bacteriocins were able to inhibit growth of a number grampositive bacteria such as Listeria monocytogenes, Clostridium botulinum, Staphylococcus aureus and Bacillus cereus. Tricine-SDS-PAGE of the active fraction resulted in single bands with estimated molecular masses of 2.5 kDA and 2.7 kDA for Lb. brevis BG18 and Lb. plantarum BG33 bacteriocins, respectively.  相似文献   
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78.
Research in the past decade has established the existence of consistent individual differences or ‘personality’ in animals and their important role in many aspects of animal behaviour. At the same time, research on honest signalling of aggression has revealed that while some of the putative aggression signals are reliable, they are only imperfectly so. This study asks whether a significant portion of the variance in the aggression-signal regression may be explained by individual differences in signalling strategies. Using the well-studied aggressive signalling system of song sparrows (Melospiza melodia), we carried out repeated assays to measure both aggressive behaviours and aggressive signalling of territorial males. Through these assays, we found that aggressive behaviours and aggressive signalling were both highly repeatable, and moreover that aggressive behaviours in 2009–2010 predicted whether the birds would attack a taxidermic mount over a year later. Most significantly, we found that residual variation in signalling behaviours, after controlling for aggressive behaviour, was individually consistent, suggesting there may be a second personality trait determining the level of aggressive signalling. We term this potential personality trait ‘communicativeness’ and discuss these results in the context of honest signalling theories and recent findings reporting prevalence of ‘under-signalling’.  相似文献   
79.
Models that couple habitat suitability with demographic processes offer a potentially improved approach for estimating spatial distributional shifts and extinction risk under climate change. Applying such an approach to five species of Australian plants with contrasting demographic traits, we show that: (i) predicted climate‐driven changes in range area are sensitive to the underlying habitat model, regardless of whether demographic traits and their interaction with habitat patch configuration are modeled explicitly; and (ii) caution should be exercised when using predicted changes in total habitat suitability or geographic extent to infer extinction risk, because the relationship between these metrics is often weak. Measures of extinction risk, which quantify threats to population persistence, are particularly sensitive to life‐history traits, such as recruitment response to fire, which explained approximately 60% of the deviance in expected minimum abundance. Dispersal dynamics and habitat patch structure have the strongest influence on the amount of movement of the trailing and leading edge of the range margin, explaining roughly 40% of modeled structural deviance. These results underscore the need to consider direct measures of extinction risk (population declines and other measures of stochastic viability), as well as measures of change in habitat area, when assessing climate change impacts on biodiversity. Furthermore, direct estimation of extinction risk incorporates important demographic and ecosystem processes, which potentially influence species’ vulnerability to extinction due to climate change.  相似文献   
80.
Sarcoidosis (SA) is an immune-mediated multisystemic disorder of unknown etiology characterized by the accumulation of lymphocytes, mononuclear phagocytes and epithelioid cell granulomas involved in different organs and tissues. The belief that genetics contribute to SA etiology is supported by twin studies, disease clustering in families and racial differences in incidence rates. Involvements of SLC11A1 in macrophage function and activation, makes it an attractive candidate gene for immune-mediated and infectious diseases. We investigated the association between SA and four polymorphisms of the SLC11A1 gene, including a single nucleotide change in intron 4 (INT4); a nonconservative single-base substitution at codon 543 (D543N); a TGTG deletion in the 3′ untranslated region; and the functional (GT)n repeat polymorphism in the 5′ region, in 95 Turkish SA patients and 150 healthy controls, by using amplification refractory mutation system–polymerase chain reaction and sequencing. We found significant association between SA and INT4 G/C allele frequency (P = 0.0000; odds ratio 2.75; 95% confidence interval 1.68–4.52) and 5′(GT)n allele 2/3 frequency (P = 0.0000; odds ratio 2.69; 95% confidence interval 1.61–4.47) suggesting that SLC11A1 might be a plausible candidate gene for SA.  相似文献   
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