953 resultados para lightener evaluation system tyrosinaseTYR


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近年来,随着黑素细胞生物学的发展和对美白剂功效研究的不断深入,美白剂对皮肤正常生理潜在的负面影响正逐渐为人们所重视 ,仅仅通过临床皮肤敏感试验已远不能给以科学的解释,因而建立一个科学量化的美白剂评价体系就显得尤为迫切和必要。本文工 作旨在将体外黑素细胞原代培养与黑素生成相关的生化指标(包括:黑度,细胞量,铬氨酸酶TYR,多巴色素异构酶DT酶活的), 检测相结合,并联系细胞学观察,从而形成一整套相对完善,定性定量的研究美白剂功效的评价体系。通过测定外加a-MSH,内皮素 ET-1及其拮抗剂GD2168后黑素细胞内上述生化指标的变化,不仅验证了a-MSH,内皮素ET-1的促黑作用,内皮素拮抗剂GD2168的美 白功效,而且还体现出本评价体系不同于国内现有的其它美白评价体系的独特优势。首先,本评价体系在国内为首家将原代培养的 黑素细胞用于美白评价,由于原代培养环境与体内皮肤生理环境的相似性,在体外对10-8mol/La-MSH产生了正常的应答,所以在评 价美白剂的功效时该培养体较之将黑素细胞孤立生长的纯化培养体系更为科学也更具有说服力。尤其值得一提的是,国内现有的生 化水平的美白评价多局限于对TYR活力的测定,而本体系的另一特点就是除了TYR外还增加了对TRP-2即DT酶活的测定,由于DT在维 持正常黑素细胞及皮肤生理上的重要意义,对其变化的研究往往可揭示出美白剂对皮肤的潜在毒性,本文通过测定并分析内皮素拮 抗剂GD2168对体外黑素细胞DT活力的下调作用,对其潜在的副作用进行了科学的预测,这项工作国内尚无人开展。Over the past few years, melanin cell research has experienced unprecedent impetus, which also contribute to the study on lightener's function especially it's potent skin damage. As a result, it's the high time to build a more accurate and complete evaluation system to investigate lightener's effects and by-effects as well. After normal human melanocytes were cultured primarily in vitro, the effects of a-MSH, endothelin-1(ET-1)and ET -1's antagonist GD2168 on melanogenesis were studied biochemically by measurement of melanin content, cell-number, tyrosinaseTYR activity and dopachrome tautomeraseDT activity. Compared with untreated cells, the treated cells responsed to 10-8mol/L a-MSH with the increase in all items. ET-1 induced both an increae in DT activity and melanin concent; however, the melanosynthesis increase was inhibited significantly in the present of GD2168. Trough above work, a new evaluation system of lightener has been established and confirmed to be feasible. Different from other evaluation systems present in country, this system used the primary culture, which was more consistent to the physiological circumstance. Moreover, the system added DT activity assay that help reveal the GD2168's potent side-effects, which would have been clouded or ignored if only TYR activity was assayed.

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Expenditure on R&D in the China construction industry has been relatively low in comparison with many developed countries for a number of years – a situation considered to be a major barrier to the industry’s competitiveness in general and unsatisfactory industry development of the 31 regions involved. A major problem with this is the lack of a sufficiently sophisticated method of objectively evaluating R&D activity in what are quite complex circumstances considering the size and regional differences that exist in this part of the world. A regional construction R&D evaluation system (RCRES) is presented aimed at rectifying the situation. This is based on 12 indicators drawn from the Chinese Government’s R&D Inventory of Resources in consultation with a small group of experts in the field, and further factor analysed into three groups. From this, the required evaluation is obtained by a simple formula. Examination of the results provides a ranking list of the R&D performance of each of the 31 regions, indicating a general disproportion between coastal and inland regions and highlighting regions receiving special emphasis or currently lacking in development. The understanding on this is vital for the future of China’s construction industry.

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Proposed transmission smart grids will use a digital platform for the automation of substations operating at voltage levels of 110 kV and above. The IEC 61850 series of standards, released in parts over the last ten years, provide a specification for substation communications networks and systems. These standards, along with IEEE Std 1588-2008 Precision Time Protocol version 2 (PTPv2) for precision timing, are recommended by the both IEC Smart Grid Strategy Group and the NIST Framework and Roadmap for Smart Grid Interoperability Standards for substation automation. IEC 61850-8-1 and IEC 61850-9-2 provide an inter-operable solution to support multi-vendor digital process bus solutions, allowing for the removal of potentially lethal voltages and damaging currents from substation control rooms, a reduction in the amount of cabling required in substations, and facilitates the adoption of non-conventional instrument transformers (NCITs). IEC 61850, PTPv2 and Ethernet are three complementary protocol families that together define the future of sampled value digital process connections for smart substation automation. This paper describes a specific test and evaluation system that uses real time simulation, protection relays, PTPv2 time clocks and artificial network impairment that is being used to investigate technical impediments to the adoption of SV process bus systems by transmission utilities. Knowing the limits of a digital process bus, especially when sampled values and NCITs are included, will enable utilities to make informed decisions regarding the adoption of this technology.

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A theoretical framework for a construction management decision evaluation system for project selection by means of a literature review. The theory is developed by the examination of the major factors concerning the project selection decision from a deterministic viewpoint, where the decision-maker is assumed to possess 'perfect knowledge' of all the aspects involved. Four fundamental project characteristics are identified together with three meaningful outcome variables. The relationship within and between these variables are considered together with some possible solution techniques. The theory is next extended to time-related dynamic aspects of the problem leading to the implications of imperfect knowledge and a non­deterministic model. A solution technique is proposed in which Gottinger's sequential machines are utilised to model the decision process,

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Mestrado em Economia e Políticas Públicas

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An in vitro study was conducted to investigate the effect of tannins on the extent and rate of gas and methane production, using an automated pressure evaluation system (APES). In this study three condensed tannins (CT; quebracho, grape seed and green tea tannins) and four hydrolysable tannins (HT; tara, valonea, myrabolan and chestnut tannins) were evaluated, with lucerne as a control substrate. CT and HT were characterised by matrix assisted laser desorption ionisation-time of flight mass spectrometry (MALDI-TOF-MS). Tannins were added to the substrate at an effective concentration of 100 g/kg either with or without polyethylene glycol (PEG6000), and incubated for 72 h in pooled, buffered rumen liquid from four lactating dairy cows. After inoculation, fermentation bottles were immediately connected to the APES to measure total cumulative gas production (GP). During the incubation, 11 gas samples were collected from each bottle at 0, 1, 4, 7, 11, 15, 23, 30, 46, 52 and 72 h of incubation and analysed for methane. A modified Michaelis-Menten model was fitted to the methane concentration patterns and model estimates were used to calculate the total cumulative methane production (GPCH4). GP and GPCH4 curves were fitted using a modified monophasic Michaelis-Menten model. Addition of quebracho reduced GP (P=0.002), whilst the other tannins did not affect GP. Addition of PEG increased GP for quebracho (P=0.003), valonea (P=0.058) and grape seed tannins (P=0.071), suggesting that these tannins either inhibited or tended to inhibit fermentation. Addition of quebracho and grape seed tannins also reduced (P≤0.012) the maximum rate of gas production, indicating that microbial activity was affected. Quebracho, valonea, myrabolan and grape seed decreased (P≤0.003) GPCH4 and the maximum rate (0.001≤ P≤ 0.102) of CH4 production. Addition of chestnut, green tea and tara tannins did not affect total gas nor methane production. Valonea and myrabolan tannins have most promise for reducing methane production as they had only a minor impact on gas production.

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Bancos comunitários de desenvolvimento no Brasil são instituições únicas que operam de acordo com os princípios da economia solidária em função da inclusão financeira de comunidades carentes. O Instituto Palmas, a instituição que assessora e coordena a rede destes bancos, pediu à Universidade de São Paulo e à Universidade de Columbia em Nova York para desenvolver um conjunto de indicadores que pudesse demonstrar o impacto social e o desempenho institucional dos bancos. Esse relatório apresenta os indicadores, a metodologia utilizada na sua formação, e recomendações para sua utilização. Na medida em que resultados e impacto estão analisados através do uso desses indicadores, a rede dos bancos comunitários e outros interessados terão mais clareza sobre suas funções, seu desempenho, e suas áreas que precisam ser melhoradas para cumprir sua missão – superar a pobreza urbana através da economia solidária.

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OBJECTIVE: The aim of this study was to evaluate the multisegmental static postural balance of active eutrophic and obese elderly women using a three-dimensional system under different sensory conditions. METHODS: A cross-sectional study was conducted on 31 elderly women (16 eutrophic and 15 obese) aged 65 to 75 years. The following anthropometric measurements were obtained: weight, height, waist and hip circumference, and handgrip strength. The physical activity level was evaluated using the International Physical Activity Questionnaire. Body composition was measured using the deuterium oxide dilution technique. The Polhemus (R) Patriot (three-dimensional) equipment was used to measure the parameters of postural balance along the anteroposterior and laterolateral axes. The data acquisition involved one trial of 60 s to test the limit of stability and four trials of 90 s each under the following conditions: (1) eyes open, stable surface; (2) eyes closed, stable surface; (3) eyes open, unstable surface; and (4) eyes closed, unstable surface. RESULTS: For the limit of stability, significant differences were observed in the maximum anteroposterior and laterolateral displacement (p<0.01) and in the parameter maximum anteroposterior displacement in the eyes closed stable surface condition (p<0.01) and maximum anteroposterior and laterolateral displacement in the eyes open unstable surface (p<0.01 and p = 0.03) and eyes closed unstable surface (p<0.01 and p<0.01) conditions. CONCLUSIONS: Obese elderly women exhibited a lower stability limit (lower sway area) compared with eutrophic women, leaving them more vulnerable to falls.

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The paper aims to develop a quasi-dynamic interregional input-output model for evaluating the macro-economic impacts of small city development. The features of the model are summarized as follows: (1) the consumption expenditure of households is regarded as an endogenous variable, (2) the technological change is determined by the change of industrial Location Quotient caused by firm's investment activities. (3) a strong feedback function between the city design and the economic analysis is provided. For checking the performance of the model, Saemangeum's Flux City Design Plan is used as the simulation target in our paper.