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1.
Short-term selective breeding created mouse lines divergent for ethanol drinking (high drinking short-term selected line [STDRHI], low drinking [STDRLO]) or ethanol-induced conditioned taste aversion (CTA; high [HTA], low [LTA]). Compared with STDRLO, STDRHI mice consumed more saccharin and less quinine, exhibited greater ethanol-induced conditioned place preference (CPP), and showed reduced ethanol stimulation and sensitization under some conditions; a line difference in ethanol-induced CTA was not consistently found. Compared with LTA, HTA mice consumed less ethanol but were similar in saccharin consumption, sensitivity to ethanol-induced CPP, and ethanol-induced locomotor stimulation and sensitization. These data suggest that ethanol drinking is genetically associated with several reward-and aversion-related traits. The interpretation of ethanol-induced CTA as more genetically distinct must be tempered by the inability to test the CTA lines beyond Selection Generation 2. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
We report on operant conditioning and artificial neural network (ANN) simulations aimed at further elucidating mechanisms of black-capped chickadee chick-a-dee call note category perception. Specifically, we tested for differences in the speed of acquisition among different discrimination tasks and, in two selected discrimination groups, searched for evidence of peak shift. Earlier, unreported ANN data were instrumental in providing the motivation for the current set of studies with chickadees and are provided here. The ANNs revealed differences in the speed of learning among note-type discrimination groups that is related to the degree of perceptual similarity among the three note types tested (i.e., A, B, and C notes). In many respects, bird and network results were in agreement (i.e., in the observation of peak shift in the same group), but they also differed in important ways (i.e., all discrimination groups showed differences in speed of learning in simulations but not in chickadees). We suggest that the start, peak and end frequency of the chick-a portion of chick-a-dee call notes, which form a graded but overlapping continuum, may drive the peak shift observed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Functional recovery after peripheral nerve injury (PNI) is poor, mainly due to the slow and incomplete regeneration of injured axons. Experimental therapies that increase the excitability of the injured axons have proven remarkably successful in promoting regeneration, but their clinical applicability has been limited. Bioluminescent optogenetics (BL-OG) uses luminopsins, fusion proteins of light-generating luciferase and light-sensing ion channels that could be used to increase neuronal excitability if exposed to a suitable substrate. Excitatory luminopsins were expressed in motoneurons of transgenic mice and in wildtype mice transduced with adeno-associated viral vectors. Intraperitoneal administration of coelenterazine (CTZ), a known luciferase substrate, generated intense bioluminescence in peripheral axons. This bioluminescence increased motoneuron excitability. A single administration of CTZ immediately after sciatic nerve transection and repair markedly enhanced motor axon regeneration. Compound muscle action potentials were 3–4 times larger than controls by 4 weeks after injury. The results observed with transgenic mice were comparable to those of mice in which the luminopsin was expressed using viral vectors. Significantly more motoneurons had successfully reinnervated muscle targets four weeks after nerve injury in BL-OG treated mice than in controls. Bioluminescent optogenetics is a promising therapeutic approach to enhancing axon regeneration after PNI.  相似文献   
4.
This study examined the relationship between groupness and self-reported exercise adherence. Exercise participants (N = 86) recalled a structured setting where they had been active with others during the last six months. To capture groupness, five group variables (i.e., common fate, mutual benefit, social structure, group processes, and self-categorization) were assessed. Indicators of self-reported adherence were participant's recall of frequency (times/month) and percent attendance in a specified structured exercise setting. Results from structural equation modeling revealed an acceptable fit: χ2 = 18.89, p > .05, Root Mean Square Error of Approximation (RMSEA) = 0.075, Comparative Fit Index (CFI) = 0.95 for the hypothesized model. Groupness was positively related to self-reported adherence explaining 20% of the variance in adherence. These findings provide preliminary support for the idea that perceiving a collection of exercise participants as being more like a group may be associated with adherence in a structured exercise setting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
Erythritol is a four‐carbon sugar alcohol produced by microorganisms as an osmoprotectant. It could be used as a natural sweetener in the pharmaceutical and food industries. Here, a snapshot of current knowledge on erythritol metabolism and synthesis, optimization of its production and more precise process and producer strain improvement is presented.  相似文献   
6.
A comprehensive review of the outcomes associated with work-to-family conflict was conducted and effect sizes were estimated. A typology was presented that grouped outcomes into 3 categories: work related, nonwork related, and stress related. Issues concerning the measurement of work-family conflict were also discussed. The results demonstrate the widespread and serious consequences associated with work-to-family conflict. On the basis of the results of the review, an agenda for future research was provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
In ongoing studies towards novel hepatitis C virus (HCV) therapeutics, inhibitors of nonstructural protein 5A (NS5A) were evaluated. Specifically, starting from previously reported lead compounds, peripheral substitution patterns of a series of biaryl‐linked pyrrolidine NS5A replication complex inhibitors were probed and structure–activity relationships were elucidated. Using molecular modelling and a supercritical fluid chromatographic (SFC) technique, intramolecular H‐bonding and peripheral functional group topology were evaluated as key determinants of activity and membrane permeability. The novel compounds exhibited retained potency as compared with the lead compounds, and also showed promising results against a panel of resistance viruses. Together, the results of the study take us a step closer towards understanding the potency of daclatasvir, a clinical candidate upon which the compounds were based, and to designing improved analogues as second‐generation antiviral agents targeting NS5A.  相似文献   
8.
9.
This study investigated the effect of fermentation conditions (time and temperature) of sorghum on the composition of ting, using the Doehlert design of response surface methodology (RSM). Fermentation temperature and time were optimized and pH, titratable acidity (TTA), total viable bacteria count (TBC), total lactic acid bacteria count (TLABC), total fungal and yeast count (TFYC), tannin content (TNC), total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activities (AA) were determined. Experimental and predicted values obtained were similar, with statistical indices indicating the validity of the models generated (R2 between 93.45 and 99.71%, AAD values close to 0, Bf and Af values close to 1). Numerical multi‐response optimization of parameters suggested optimal fermentation conditions to be 34 °C for 24 hr. Physicochemical characterization of ting samples using scanning electron microscopy (SEM), X‐ray diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR) showed slight changes in morphology, similarity in diffraction patterns and presence of different functional groups, respectively. Results of this study could provide information for the commercialization of quality ting.

Practical applications

Response surface methodology was used to study the influence of fermentation conditions on the quality of ting and optimal fermentation conditions were obtained at 34 °C for 24 hr. The findings in this study will be useful for ting processors to obtain a product with maximal beneficial composition and traits.  相似文献   
10.
Biofuels have been identified as a potential short-term solution for reducing greenhouse gas (GHG) emissions from road transport. Currently, ‘1st generation’ biofuels are produced from food crops, but there are concerns with the indirect effects of utilising edible crops for fuel. There is increased interest in producing ‘2nd generation’ biofuels from woody crops and straw, as these can be grown on lower grade land or do not compete directly with food. In order to ensure that biofuels actually deliver emission savings, the overall GHG balance of producing them must be calculated accurately, and compared with conventional fossil fuels. The GHG balance can vary significantly however, depending on biomass type, the production processes, the indirect effects, and also by the method by which the GHG emission balance is calculated. Currently, in the UK, there are three main GHG methodologies that potentially affect biofuel producers. Each has a different approach to measure GHG emissions from biofuel production, and each provides a different result, causing difficulties for policy makers. This study performs a partial life cycle assessment for bioethanol production from wheat grain and wheat straw to demonstrate the variability of the results between methodologies.  相似文献   
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