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41.
Functional expression and synergistic cooperation of xylan‐degrading enzymes from Hypocrea orientalis and Aspergillus niger 下载免费PDF全文
42.
Daniela F. S. Fonseca ?ngelo C. Salvador Sónia A. O. Santos Carla Vilela Carmen S. R. Freire Armando J. D. Silvestre Sílvia M. Rocha 《International journal of molecular sciences》2015,16(6):14194-14209
The lipophilic composition of wild Arbutus unedo L. berries, collected from six locations in Penacova (center of Portugal), as well as some general chemical parameters, namely total soluble solids, pH, titratable acidity, total phenolic content and antioxidant activity was studied in detail to better understand its potential as a source of bioactive compounds. The chemical composition of the lipophilic extracts, focused on the fatty acids, triterpenoids, sterols, long chain aliphatic alcohols and tocopherols, was investigated by gas chromatography–mass spectrometry (GC–MS) analysis of the dichloromethane extracts. The lipophilic extractives of the ripe A. unedo berries ranged from 0.72% to 1.66% (w/w of dry weight), and consisted mainly of triterpenoids, fatty acids and sterols. Minor amounts of long chain aliphatic alcohols and tocopherols were also identified. Forty-one compounds were identified and among these, ursolic acid, lupeol, α-amyrin, linoleic and α-linolenic acids, and β-sitosterol were highlighted as the major components. To the best of our knowledge the current research study provides the most detailed phytochemical repository for the lipophilic composition of A. unedo, and offers valuable information for future valuation and exploitation of these berries. 相似文献
43.
Andreas P. Kyriacou Leonel Muinelo-Gallo Oriol Roca-Sagalés 《Papers in Regional Science》2015,94(1):89-107
In this paper we consider how government quality mediates the relationship between fiscal decentralization and regional disparities. Previous work has argued that fiscal decentralization has the potential to reduce income differences across regions but that this potential may not be realized because of governance problems associated with sub-national authorities. Our empirical evidence based on a sample of 24 OECD countries over the period 1984 to 2006 lends a measure of support to this idea. We find that fiscal decentralization promotes regional convergence in high government quality settings but, worryingly, it leads to wider regional disparities in countries with poor governance. 相似文献
44.
Phytochemical screening assay on crude extracts of Ocimum tenuiflorum L. leaves and methanol fractions was performed in this study. Phytochemical qualitative assay on aqueous crude extract and aqueous fraction did not show any steroid and terpenoid. However, ethanol and butanol fractions also did not show steroid in the screening test. The result of HPLC identification of active crude extracts and active fractions showed the possible bioactive compounds in this plant extracts, which may control diabetes. These findings showed that the active crude extract (methanol) and its active fractions (ethyl acetate, and butanol) showed the presence of polyphenolic active constituents such as 3,4-dimethoxycinnamic acid, caffeic acid, diosmetin, luteolin, kaempferol, rosmarinic acid, apigenin, and genistein that control the blood glucose in diabetic rats. Furthermore, isolation of the active components may pave the way for the development of new agents for the treatment of diabetes and its complications. 相似文献
45.
This is the first study that uses multilevel modelling to analyse regional influence on the decision to invest in innovation activities of firms in a single developing country, Ecuador. Our results indicate that the decision to invest in R&D and in other innovation activities are conditioned by the region in which the firm is located. Regional loan volume, orientation towards knowledge exploitation and intra-regional-sectorial R&D spillovers are positively associated with both types of innovation activities, while regional levels of co-operation and inter-regional R&D spillovers are only positively associated with the probability of investing in other innovation activities. 相似文献
46.
Mariana Pereira Barbosa Thaís Caroline Buttow Rigolon Larissa Lorrane Rodrigues Borges Valéria Aparecida Vieira Queiroz Paulo César Stringheta Frederico Augusto Ribeiro de Barros 《International Journal of Food Science & Technology》2021,56(9):4746-4755
This work aimed to evaluate the stability of sorghum 3-deoxyanthocyanins (DXA) in model beverages (pH 3.5) elaborated with crude sorghum phenolic extract, containing ascorbic acid and sulphite, under fluorescent light exposure and subjected to heat treatment. There was no significant difference in the DXA degradation during storage under light exposure (24.16%) and absence of light (20.72%). DXA degradation did not differ in the presence of ascorbic acid during storage under light exposure (23.99–25.38%) and absence of light (19.87–21.74%). The addition of sulphite caused an initial bleaching reaction, but as a reversible reaction, the anthocyanin content was higher on the last day of storage compared to the first day. There were no significant differences in total anthocyanin content of all treatments subjected to the heat treatment (80 °C for 5 and 25 min). Thus, crude DXA are very stable under light, additives and heat, and may be useful as natural food colourants. 相似文献
47.
目的:重庆市具有丰富的医药产业底蕴和极佳的医疗资源,在我国药品注册审评制度改革紧密推进和重庆市大力发展生物医药产业的大背景下,本课题从对重庆市药物临床试验机构(以下简称机构)管理人员调研的角度入手,旨在明确重庆市机构建设现状与问题,探讨可行的创新发展对策。方法:本研究对我市20家有药物临床试验资质机构的54位管理人员问卷数据进行统计;并通过比对相应的公共数据,系统分析我市机构建设水平。结果:问卷分析显示,我市机构仍以传统GCP架构模式为主;以承担国内企业项目为主(90.00%),65.00%的机构近三年承接项目总数在40项以下;机构管理者多数从事机构相关工作的工作年限多在6年以内(79.59%),且仍有部分机构管理者未接受系统的培训;对公共数据调查分析显示,截至2019年5月底,我市机构总数目为22家,自2017年7月22日以来承接在Clinical Trails注册的在研项目数为81项,远低于机构工作开展较好的城市(北京:61家,433项;上海:53家,326项)。结论:重庆市机构建设水平亟待提高,应整合全市临床研究资源,构建区域化的药物临床试验机构体系,加速重庆市医药产业的创新发展。 相似文献
48.
Around the globe, intermittent renewable energies in the form of wind and solar power are on the rise. Their subsidization can be seen as a market intervention, which may deter optimal investment. Thus, this study tests the effect of renewable energies on investment in conventional electricity generation technologies. We estimate a dynamic investment model for 14 European economies for the period 2004–2016 and find a non-negligible negative impact of intermittent renewables on investment in peak-load capacity (mainly gas), while base-load (particularly coal) plants are unaffected. However, the production flexibility of gas-fired plants represents a particularly vital function to balance the supply intermittency of wind and solar. Thus, dispatchable conventional power plants are still necessary to back the system under scarcity events, such as unfavorable weather conditions during high electricity demand. Policymakers should be aware of the adverse effects of RES on investment in peak-load plants and may consider a redesign of the current system, for example by introducing capacity markets. 相似文献
49.
针对依兰三矿极复杂地质条件下近距离突出煤层群开采时面临的瓦斯突出和回采工作面瓦斯超限、自然发火等问题,从保护层开采影响范围、开采后的残余瓦斯压力、回采面瓦斯涌出量、煤层自然发火角度分析了各煤层开采顺序,确定了首采面布置在上1煤层,从上至下依次开采较为合理。回采前确定采用千米定向钻机预抽中煤层巷道区域瓦斯+中煤层穿层钻孔预抽上1煤层条带瓦斯的区域消突方法;回采期间工作面采用高位钻孔+顺层钻孔的瓦斯治理方法,从而实现卸压抽采、条带消突预抽、实施防灭火工程等。采用以上瓦斯治理方法能够有效解决工作面瓦斯超限,达到了区域消突的目的,千米钻机长钻孔钻孔抽放浓度维持在80%以上,回风流瓦斯体积分数基本稳定在0.4%以下。 相似文献
50.
针对高强汽车钢生产合同量小、规格繁多,混浇坯和合同余材多的问题,以550L带钢的生产为例,研究了终轧温度、冷却速率对550L带钢组织以及力学性能的影响。结果表明,粗轧在再结晶区利用大变形量获得细小均匀的奥氏体组织;精轧采用低温轧制,获得内部有大量变形带的扁平状奥氏体组织,可以提高晶界面积,增加相变形核核心和驱动力,在随后的超快密集冷却过程中形成晶粒细小的铁素体组织,充分发挥细晶强化、相变强化、析出强化、位错强化的作用,使其性能达到高级别600L牌号带钢性能,实现了升级轧制,解决了上述问题。 相似文献