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Ethanol fermentation from Jerusalem artichoke tubers was performed at elevated temperatures by the consolidated bioprocessing strategy using Saccharomyces cerevisiae MK01 expressing inulinase through cell surface display. No significant difference was observed in yeast growth when temperature was controlled at 38 and 40 °C, respectively, but inulinase activity with yeast cells was substantially enhanced at 40 °C. As a result, enzymatic hydrolysis of inulin was facilitated and ethanol production was improved with 89.3 g/L ethanol produced within 72 h from 198.2 g/L total inulin sugars consumed. Similar results were also observed in ethanol production from Jerusalem artichoke tubers with 85.2 g/L ethanol produced within 72 h from 185.7 g/L total sugars consumed. On the other hand, capital investment on cooling facilities and energy consumption for running the facilities would be saved, since regular cooling water instead of chill water could be used to cool down the fermentation system.  相似文献   
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This paper proposes a modified BFGS formula using a trust region model for solving nonsmooth convex minimizations by using the Moreau-Yosida regularization (smoothing) approach and a new secant equation with a BFGS update formula. Our algorithm uses the function value information and gradient value information to compute the Hessian. The Hessian matrix is updated by the BFGS formula rather than using second-order information of the function, thus decreasing the workload and time involved in the computation. Under suitable conditions, the algorithm converges globally to an optimal solution. Numerical results show that this algorithm can successfully solve nonsmooth unconstrained convex problems.  相似文献   
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OBJECTIVE--To describe the epidemiology of primary bacterial meningitis in the North East Thames region over a three year period before and during the introduction of the vaccine for Haemophilus influenzae type b. DESIGN--Analysis of information on cases of primary bacterial meningitis identified by microbiology laboratories in the region, with collection of case data by questionnaire. MAIN OUTCOME MEASURES--Annual incidence rates for types of meningitis according to age and ethnic group. RESULTS--The annual incidence rates for the three major causes of bacterial meningitis in the general population were 1.9/100,000 for Neisseria meningitidis, 1.6/100,000 for Haemophilus influenzae before vaccination, and 1.0/100,000 for Streptococcus pneumoniae. Higher rates of H influenzae meningitis were found in Asians compared with white people (3.6/100,000 v 1.5/100,000, P = 0.01). As a result of the vaccine programme introduced in October 1992 the number of cases of H influenzae meningitis in children under 5 years has fallen by 87%. CONCLUSIONS--Bacterial meningitis is a serious problem especially in preschool children. There are differences in the incidence of some causes of bacterial meningitis in different ethnic groups; with H influenzae type b being significantly more common among black and Asian people than among white people. The immunisation programme for H influenzae type b in the North East Thames region has been successful in reducing the incidence of this type of meningitis in Asian and white populations. The numbers were too small to evaluate in the black population.  相似文献   
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The interactions between human serum albumin (HSA) and fluphenazine (FPZ) in the presence or absence of rutin or quercetin were studied by fluorescence, absorption and circular dichroism (CD) spectroscopy and molecular modeling. The results showed that the fluorescence quenching mechanism was static quenching by the formation of an HSA–FPZ complex. Entropy change (ΔS 0) and enthalpy change (ΔH 0) values were 68.42 J/(mol? K) and ?4.637 kJ/mol, respectively, which indicated that hydrophobic interactions and hydrogen bonds played major roles in the acting forces. The interaction process was spontaneous because the Gibbs free energy change (ΔG 0) values were negative. The results of competitive experiments demonstrated that FPZ was mainly located within HSA site I (sub‐domain IIA). Molecular docking results were in agreement with the experimental conclusions of the thermodynamic parameters and competition experiments. Competitive binding to HSA between flavonoids and FPZ decreased the association constants and increased the binding distances of FPZ binding to HSA. The results of absorption, synchronous fluorescence, three‐dimensional fluorescence, and CD spectra showed that the binding of FPZ to HSA caused conformational changes in HSA and simultaneous effects of FPZ and flavonoids induced further HSA conformational changes.  相似文献   
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The genetic adaptation of Tibetans to high altitude hypoxia likely involves a group of genes in the hypoxic pathway,as suggested by earlier studies.To test the adaptive role of the previously reported candidate gene EP300 (histone acetyltransferase p300),we conducted resequencing of a 108.9 kb gene region of EP300 in 80 unrelated Tibetans.The allele-frequency and haplotype-based neutrality tests detected signals of positive Darwinian selection on EP300 in Tibetans,with a group of variants showing allelic divergence between Tibetans and lowland reference populations,including Han Chinese,Europeans,and Africans.Functional prediction suggested the involvement of multiple EP300 variants in gene expression regulation.More importantly,genetic association tests in 226 Tibetans indicated significant correlation of the adaptive EP300 variants with blood nitric oxide (NO) concentration.Collectively,we propose that EP300 harbors adaptive variants in Tibetans,which might contribute to high-altitude adaptation through regulating NO production.  相似文献   
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李文卿  江源  赵守栋  张凌楠  刘锬 《生态学报》2017,37(10):3365-3374
研究利用在六盘山地区采集的油松树轮样芯建立树轮宽度标准年表(STD),分别与不同长度时间单元(月、半月、旬)和多时间尺度的标准化降水指数(SPIn)序列进行相关性分析。油松标准年表与不同长度时间单元SPI的相关结果显示,较小的时间单元会使相关性表达更加精确,而时间单元过小则会因为数据波动性增大而导致相关关系弱化。因此,相较于月和旬,半月是相关性分析更为合适的时间单元长度。油松标准年表与多时间尺度SPI的相关结果显示,SPI多时间尺度的特性有助于揭示油松径向生长对不同时间尺度水分状况的响应特征,且油松在不同生长时期对于不同时间尺度水分状况具有相异的响应机制。在温度较低(0℃)的冬季,短时间内的降水并不利于树木生长,而长时间良好的水分储备会为树木生长季需水提供保障;在生长季前期,长时间良好的水分状况比短期内的降水更有利于树木的生长;在生长季,补给性水分和土壤水分都对树木生长起着至关重要的作用。  相似文献   
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