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《Bioscience, biotechnology, and biochemistry》2013,77(3):606-611
The effects of pressure on the enzyme activities of Lacto-bacillus helveticus LHE-511 were examined. Treatment at 400 MPa at 30°C for 10 min completely inhibited acid-producing activity, but the activities of aminopeptidase (AP) and X-prolyl dipeptidyl aminopeptidase (X-PDAP), which are important for acceleration of cheese ripening, increased. These results showed that pressure treatment of L. helveticus LHE-511 selectively inactivates its acid-producing activity. 相似文献
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Identifying genes that direct the mechanism of a disease from expression data is extremely useful in understanding how that mechanism works. This in turn may lead to better diagnoses and potentially could lead to a cure for that disease. This task becomes extremely challenging when the data are characterised by only a small number of samples and a high number of dimensions, as is often the case with gene expression data. Motivated by this challenge, we present a general framework that focuses on simplicity and data perturbation. These are the keys for robust identification of the most predictive features in such data. Within this framework, we propose a simple selective naive Bayes classifier discovered using a global search technique, and combine it with data perturbation to increase its robustness for small sample sizes.An extensive validation of the method was carried out using two applied datasets from the field of microarrays and a simulated dataset, all confounded by small sample sizes and high dimensionality. The method has been shown to be capable of selecting genes known to be associated with prostate cancer and viral infections. 相似文献
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Clare Brant 《Ethnos》2013,78(4):544-563
Olfactory studies are truly multidisciplinary, from anthropology to zoology. What literary criticism can offer is analysis of the language of smell and the discourses of olfactory practice which give smell meanings. In this paper I explore the poetics of odour in selected contexts in the developed West of the twenty-first century. I argue that the language of smell is elusive, contradictory, disguised: nonetheless, it deploys metaphor, story, personal meaning and social meaning, all frames that ‘nest’ together. I demonstrate contradictions of olfactory practice with reference to urban space and technologies of scent, acting on bodies and places. I argue that a relationship between scent, identity and space can be understood in terms of an olfactory sublime, to which there is also resistance, sanctioned by new laws. In public space, the complexity of deodorisation appears in the conflict between fragrance-free and compulsory olfaction, as I argue with reference to Halifax, Nova Scotia and to the London Underground. 相似文献
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《Current biology : CB》2014,24(15):1723-1730
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Ying-Ju Lai Gwo-Jyh Chang Yung-Hsin Yeh Jong-Hwei S. Pang Chung-Chi Huang Wei-Jan Chen 《PloS one》2015,10(9)
Gamma-secretase-mediated Notch3 signaling is involved in smooth muscle cell (SMC) hyper-activity and proliferation leading to pulmonary arterial hypertension (PAH). In addition, Propylthiouracil (PTU), beyond its anti-thyroid action, has suppressive effects on atherosclerosis and PAH. Here, we investigated the possible involvement of gamma-secretase-mediated Notch3 signaling in PTU-inhibited PAH. In rats with monocrotaline-induced PAH, PTU therapy improved pulmonary arterial hypertrophy and hemodynamics. In vitro, treatment of PASMCs from monocrotaline-treated rats with PTU inhibited their proliferation and migration. Immunocyto, histochemistry, and western blot showed that PTU treatment attenuated the activation of Notch3 signaling in PASMCs from monocrotaline-treated rats, which was mediated via inhibition of gamma-secretase expression especially its presenilin enhancer 2 (Pen-2) subunit. Furthermore, over-expression of Pen-2 in PASMCs from control rats increased the capacity of migration, whereas knockdown of Pen-2 with its respective siRNA in PASMCs from monocrotaline-treated rats had an opposite effect. Transfection of PASMCs from monocrotaline-treated rats with Pen-2 siRNA blocked the inhibitory effect of PTU on PASMC proliferation and migration, reflecting the crucial role of Pen-2 in PTU effect. We present a novel cell-signaling paradigm in which overexpression of Pen-2 is essential for experimental pulmonary arterial hypertension to promote motility and growth of smooth muscle cells. Propylthiouracil attenuates experimental PAH via suppression of the gamma-secretase-mediated Notch3 signaling especially its presenilin enhancer 2 (Pen-2) subunit. These findings provide a deep insight into the pathogenesis of PAH and a novel therapeutic strategy. 相似文献
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Abstract We investigate the selective adsorption of xenon, argon, and methane in zeolite NaA by applying the grand canonical ensemble Monte Carlo simulation technique to an adsorbed binary mixture and to two reference systems: i) an adsorbed single component system and ii) a bulk mixture. We define and calculate selectivities and excess densities due to i) mixing and ii) adsorption in terms of differences between the binary adsorbed system and these reference systems. We observe that xenon selectively adsorbs in both xenon-argon and xenon-methane mixtures at low chemical potential (low pressure) due to its greater energetic interaction with the zeolite. However, a reversal in selectivity occurs at higher chemical potential in both of these mixtures. This is due in large part to the greater efficiency in which the smaller component “packs” in the pore as compared to the bulk. We show that the crossover in selectivity occurs at a lower chemical potential for a mixture where one component can occupy regions of the porespace inaccessible to the other. We suggest that this crossover in selectivity may be a general feature of microporous adsorption. 相似文献
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Biochemical Studies of Olfaction: Binding Specificity of Odorants to a Cilia Preparation from Rainbow Trout Olfactory Rosettes 总被引:3,自引:0,他引:3
Cilia isolated from the olfactory epithelium (olfactory rosettes) of rainbow trout (Salmo gairdneri) bind amino acids, which are odor stimuli to this species. We demonstrate that L-threonine, L-serine, and L-alanine bind to a common site, TSA, in the cilia preparation. All possible mixtures of two of the amino acids as competitors, with the third as the 3H-labeled ligand, were studied. The effect of two combined (unlabeled) competitors was always substantially less than additive compared with their actions singly. Along with additional inhibition studies using mixtures of inhibitors, the data show that the three odorants must interact with at least one common binding site, TSA. Binding of L-[3H]lysine to site L was unaffected by addition of L-threonine, L-serine, or L-alanine, establishing its independence from site TSA. L-Arginine inhibited binding of L-[3H]lysine, showing that both of these basic amino acids interact with site L. The data establish the presence, in trout olfactory cilia, of at least two separate and noninteracting populations of odorant binding sites, TSA and L. 相似文献
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Sampling devices differing greatly in shape, size and operating condition have been used to collect air samples to determine rates of emission of volatile substances, including odour. However, physical chemistry principles, in particular the partitioning of volatile substances between two phases as explained by Henrys Law and the relationship between wind velocity and emission rate, suggests that different devices cannot be expected to provide equivalent emission rate estimates. Thus several problems are associated with the use of static and dynamic emission chambers, but the more turbulent devices such as wind tunnels do not appear to be subject to these problems. In general, the ability to relate emission rate estimates obtained from wind tunnel measurements to those derived from device-independent techniques supports the use of wind tunnels to determine emission rates that can be used as input data for dispersion models. 相似文献
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Wu XL Macneil MD De S Xiao QJ Michal JJ Gaskins CT Reeves JJ Busboom JR Wright RW Jiang Z 《Genetica》2005,125(1):103-113
Candidate gene approaches provide tools for exploring and localizing causative genes affecting quantitative traits and the underlying variation may be better understood by determining the relative magnitudes of effects of their polymorphisms. Diacyglycerol O-acyltransferase 1 (DGAT1), fatty acid binding protein (heart) 3 (FABP3), growth hormone 1 (GH1), leptin (LEP) and thyroglobulin (TG) have been previously identified as genes contributing to genetic control of subcutaneous fat thickness (SFT) in beef cattle. In the present research, Bayesian model selection was used to evaluate effects of these five candidate genes by comparing competing non-nested models and treating candidate gene effects as either random or fixed. The analyses were implemented in SAS to simplify the programming and computation. Phenotypic data were gathered from a F2 population of Wagyu × Limousin cattle. The five candidate genes had significant but varied effects on SFT in this population. Bayesian model selection identified the DGAT1 model as the one with the greatest model probability, whether candidate gene effects were considered random or fixed, and DGAT1 had the greatest additive effect on SFT. The SAS codes developed in the study are freely available and can be downloaded at: http://www.ansci.wsu.edu/programs/.Mention of a proprietary product does not constitute a guarantee or warranty of the product by USDA, Montana AES, or the authors and does not imply its approval to the exclusion of other products that may also be suitable. 相似文献
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Murphy PG 《The Clinical biochemist. Reviews / Australian Association of Clinical Biochemists》2008,29(Z1):S17-S22
This article aims to: provide a broad overview of the three stage process of introducing a new or modified method into the clinical diagnostic laboratory; outline general principles and strategies that can be utilised in the process of selecting a suitable method; give a practical example of how these principles and strategies can be applied. 相似文献
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利用HMW-GS优异种质和矮败小麦遗传改良工具,通过苗期HMW-GS基因PCR分子跟踪并结合籽粒SDS-PAGE检测,将优异HMW-GS导入并聚合于矮败小麦,构建矮败小麦优质轮回选择群体.结果表明,在开花期对轮回选择群体的287个单株进行1Dx5和1Bx14基因的PCR检测,有225个单株携带1Dx5基因,有120个单株携带1Bx14基因;其中,有58个单株同时携带1Dx5和1Bx14基因.对群体中287个单株籽粒的HMW-GS组成进行分析,有22%籽粒在Glu-B1、Glu-D1位点发生了亚基聚合:224个单株携带5+10亚基,126个单株携带14+15亚基,有63个单株同时携带5+10+14+15. 相似文献
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Hudson N McGahan E Casey K Lowe S Galvin G Jeston P Dunlop M 《Bioresource technology》2007,98(10):1877-1887
Odour emission rates were measured for seven different anaerobic ponds treating piggery wastes at six to nine discrete locations across the surface of each pond on each sampling occasion over a 14-month period. Emission rate values varied between ponds, between seasons for the same pond and even for the same pond on different days of a sampling week. Average seasonal emission rates ranged from 7.9 to 46.5OU/m(2)s, while average emission rates ranged from 16.0 to 29.0OU/m(2)s. Factors potentially responsible for the variability in emission rates were investigated, including air and pond liquor temperatures, time of day of sample collection, season and the impact of a prolonged drought. 相似文献
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Summary The objective of the work was to select Citrus plants more tolerant to elevated NaCl concentrations in the irrigation water. For this purpose, unfertilized Troyer citrange ovules treated with a chemical mutagenic agent (ethyl methane sulphonate) were cultured in vitro. Whole plants were regenerated from embryos developed in the nucellar tissue of the ovule. The screening for salt tolerance was achieved by irrigating these plants with a nutrient solution containing 45 mM NaCl.Plants obtained from vegetative propagation of the selected plant show faster growth, less leaf damage and lower concentrations of Cl– and Na+ in leaves than the original clone with increasing NaCl levels in the nutrient solution. In addition, the selected plant accumulated more Na+ in shoots and roots and this was accompanied by a significant reduction in K+concentration. It can be concluded that the selected plant restricts the accumulation of Na+ in leaves by concentrating Na+ in shoots and roots.Abbreviations EMS
ethyl-methane-sulphonate
- IBA
indole 3-butyric acid 相似文献
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Rod N. Millward Kevin R. Carman John W. Fleeger Ralph Portier 《Journal of experimental marine biology and ecology》2004,310(1):115-130
A microcosm experiment was used to examine the effects of co-contamination with environmentally realistic but relatively low concentrations (expected to cause occasional to frequent adverse effects) of diesel fuel and metals (Cu, Cd, Hg, Cr, and Pb) on a saltmarsh benthic invertebrate community. After 30 days, exposure to metals did not influence abundances of major meiofaunal taxa (nematodes, ostracods, total copepods, nauplii, or chironomid larvae) or individual copepod species. Diesel exposure did not influence nematode or total copepod abundances, but significantly decreased abundances of ostracods, nauplii, and chironomids. For all taxa except copepods, the metals+diesel treatment yielded results similar to the effects of diesel alone. Although total copepod abundances were not significantly influenced by metals- or diesel-only treatments, abundances were significantly reduced in the metals+diesel treatment, a response that appeared consistent with a non-additive toxicological synergism between metals and diesel. Responses of copepod species to the diesel-only treatment were varied; species could be categorized as ‘diesel-sensitive’ (declined in abundance, presumably due to direct (toxic) effects), or ‘diesel-resistant’ (abundance either unchanged, or increased due to indirect (ecological) effects). In the metals+diesel treatment, the effects on ‘diesel-sensitive’ species were similar to those observed in the diesel-only treatment. However, abundances of ‘diesel-resistant’ species declined in the metals+diesel treatment, suggesting that metals interfere with the indirect effects that lead to enhanced abundances of some species and/or that metal+diesel combinations are uniquely toxic. Collectively, however, responses of most individual copepod species to metals+diesel suggested an additive toxicological action, and thus differed from the apparent synergism observed for total copepod abundance. The presence of diesel enhanced the retention of metals in sediments, which may have important toxicological implications. We conclude that, at relatively low concentrations of metal and diesel fuel co-contamination, both direct (toxic) and indirect effects influence faunal abundance; thus, reductions in abundance of major taxa may give the appearance of toxicological synergisms that are not manifested at the species level. 相似文献
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Zlenko Dmitry V. Skoblin Aleksey A. Vedenkin Alexander S. Mikhaleva Mariya G. Zanin Anatoly M. Tverdislov Vsevolod A. Stovbun Sergey V. 《Origins of life and evolution of the biosphere》2020,50(1-2):77-86
Origins of Life and Evolution of Biospheres - The N-trifluoroacetylated α-aminoalcohols (TFAAAs) are able to form quasi-one-dimensional supramolecular fibers (strings) when chirally pure, and... 相似文献
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Halogen-containing plasmas are often used to form topological structures on semiconductor surfaces; therefore, spectral monitoring of the etching process is an important diagnostic tool in modern electronics. In this work, the emission spectra of gas discharges in mixtures of hydrogen chloride with argon, chlorine, and hydrogen in the presence of a semiconducting gallium arsenide plate were studied. Spectral lines and bands of the GaAs etching products appropriate for monitoring the etching rate were determined. It is shown that the emission intensity of the etching products is proportional to the GaAs etching rate in plasmas of HCl mixtures with Ar and Cl2, which makes it possible to monitor the etching process in real time by means of spectral methods. 相似文献