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High field (400 and 600 MHz) proton NMR spectroscopy has been employed to investigate the thermally-induced autoxidation of glycerol-bound polyunsaturated fatty acids present in intact culinary frying oils and fats. Heating of these materials at 180°C for periods of 30, 60 and 90 min. generated a variety of peroxidation products, notably aldehydes (alkanals, trans-2-alkenals and alka-2, 4-dienals) and their conjugated hydroperoxydiene precursors. Since such aldehydes appear to be absorbed into the systemic circulation from the gut in vivo, the toxicological significance of their production during standard frying practices is discussed.  相似文献   
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Japanese and American subjects were required to sort filterpapers, soaked in taste stimuli, into categories that had conceptuallythe same taste. Both Japanese and Americans sorted in the samemanner, indicating similar conceptualization. Taste names weregiven to the taste categories obtained by using the traditional‘four basic taste’ naming system, common in tastepsychophysics. This method was seen to underestimate the numberof categories actually present. This suggests a re-assessmentof current psychophysical taste-naming techniques.  相似文献   
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The Food and Drug Administration (FDA) initiative of Process Analytical Technology (PAT) encourages the monitoring of biopharmaceutical manufacturing processes by innovative solutions. Raman spectroscopy and the chemometric modeling tool partial least squares (PLS) have been applied to this aim for monitoring cell culture process variables. This study compares the chemometric modeling methods of Support Vector Machine radial (SVMr), Random Forests (RF), and Cubist to the commonly used linear PLS model for predicting cell culture components—glucose, lactate, and ammonia. This research is performed to assess whether the use of PLS as standard practice is justified for chemometric modeling of Raman spectroscopy and cell culture data. Model development data from five small-scale bioreactors (2 × 1 L and 3 × 5 L) using two Chinese hamster ovary (CHO) cell lines were used to predict against a manufacturing scale bioreactor (2,000 L). Analysis demonstrated that Cubist predictive models were better for average performance over PLS, SVMr, and RF for glucose, lactate, and ammonia. The root mean square error of prediction (RMSEP) of Cubist modeling was acceptable for the process concentration ranges of glucose (1.437 mM), lactate (2.0 mM), and ammonia (0.819 mM). Interpretation of variable importance (VI) results theorizes the potential advantages of Cubist modeling in avoiding interference of Raman spectral peaks. Predictors/Raman wavenumbers (cm−1) of interest for individual variables are X1139–X1141 for glucose, X846–X849 for lactate, and X2941–X2943 for ammonia. These results demonstrate that other beneficial chemometric models are available for use in monitoring cell culture with Raman spectroscopy.  相似文献   
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Membrane fusion for exocytosis is mediated by SNAREs, forming trans-ternary complexes to bridge vesicle and target membranes. There is an array of accessory proteins that directly interact with and regulate SNARE proteins. PRIP (phospholipase C-related but catalytically inactive protein) is likely one of these proteins; PRIP, consisting of multiple functional modules including pleckstrin homology and C2 domains, inhibited exocytosis, probably via the binding to membrane phosphoinositides through the pleckstrin homology domain. However, the roles of the C2 domain have not yet been investigated. In this study, we found that the C2 domain of PRIP directly interacts with syntaxin 1 and SNAP-25 but not with VAMP2. The C2 domain promoted PRIP to co-localize with syntaxin 1 and SNAP-25 in PC12 cells. The binding profile of the C2 domain to SNAP-25 was comparable with that of synaptotagmin I, and PRIP inhibited synaptotagmin I in binding to SNAP-25 and syntaxin 1. It was also shown that the C2 domain was required for PRIP to suppress SDS-resistant ternary SNARE complex formation and inhibit high K+-induced noradrenalin release from PC12 cells. These results suggest that PRIP inhibits regulated exocytosis through the interaction of its C2 domain with syntaxin 1 and SNAP-25, potentially competing with other SNARE-binding, C2 domain-containing accessory proteins such as synaptotagmin I and by directly inhibiting trans-SNARE complex formation.  相似文献   
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Capsule Little Owls take a wide variety of food, most of which is made up of earthworms, but also includes bats.  相似文献   
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Nicotinic acetylcholine receptors (nAChRs) are highly expressed at the vertebrate neuromuscular junction (NMJ) where they are required for muscle activation. Understanding the factors that underlie NMJ development is critical for a full understanding of muscle function. In this study we performed whole cell and outside‐out patch clamp recordings, and single‐cell RT‐qPCR from zebrafish red and white muscle to examine the properties of nAChRs during the first 5 days of development. In red fibers miniature endplate currents (mEPCs) exhibit single exponential time courses at 1.5 days postfertilization (dpf) and double exponential time courses from 2 dpf onwards. In white fibers, mEPCs decay relatively slowly, with a single exponential component at 1.5 dpf. By 2 and 3 dpf, mEPC kinetics speed up, and decay with a double exponential component, and by 4 dpf the exponential decay reverts back to a single component. Single channel recordings confirm the presence of two main conductance classes of nAChRs (~45 pS and ~65 pS) in red fibers with multiple time courses. Two main conductance classes are also present in white fibers (~55 pS and ~73 pS), but they exhibit shorter mean open times by 5 dpf compared with red muscle. RT‐qPCR of mRNA for nicotinic receptor subunits supports a switch from γ to ε subunits in white fibers but not in red. Our findings provide a developmental profile of mEPC properties from red and white fibers in embryonic and larval zebrafish, and reveal previously unknown differences between the NMJs of these muscle fibers.© 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 916–936, 2016  相似文献   
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Globally, river degradation has decimated freshwater fish populations. To help reverse this trend in a southeastern Australia river, we used multiple restoration actions, including reintroduction of instream woody habitat, riparian revegetation, removal of a weir hindering fish movement, fencing out livestock, and controlling riparian weeds. We monitored the responses of native fish at the segment scale (20 km) and reach scale (0.3 km) over 7 years to assess the effectiveness of the different restoration strategies. Two closely related species, Murray cod Maccullochella peeli and trout cod Maccullochella macquariensis, increased at the restored segment compared with the control segment. However, inherent differences between river segments and low sample size hampered assessment of the mechanisms responsible for segment‐scale changes in fish abundance. In contrast, at the reach scale, only M. peeli abundance significantly increased in reaches supplemented with wood. These differential responses by 2 closely related fish species likely reflect species‐specific responses to increased habitat availability and enhanced longitudinal connectivity when the weir improved passage around a fishway. Changes in M. peeli abundance in segments supplemented with and without wood suggest an increase in carrying capacity and not simply a redistribution of individuals within the segment, facilitated the observed expansion. Our findings confirm the need to consider individual fish species' habitat preferences carefully when designing restoration interventions. Further, species‐specific responses to restoration actions provide waterway managers with precise strategies to target fish species for recovery and the potential to predict fish outcomes based on ecological preferences.  相似文献   
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