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为了确定高在鼢鼠(Myospalax baileyi)体内抗缺氧水成分,通过超临界萃取(SCEF)方法从高原鼢鼠肌肉提取脂溶性部分,我们对其成分通过气相色谱-质谱(GC-MS)联用分析。为了证实高原鼢鼠肌肉脂溶性成分的抗缺氧效果,探讨其抗缺氧机制,我们以小鼠为实验动物,分为5个组,即高剂量实验组(HEG),中剂量实验组(MEG),低剂量实验组(LEG),阳性药物对照组(PEG),空白对照组(CEG),分别以浓度为20%萃取物,10%萃取物,5%萃取物,10%的红景天和蒸馏水连续饲喂10天,然后进行小鼠常压抗缺氧实验,测定小鼠血清超氧化物歧化酶(SOD),谷光甘肽过氧化物酶(GSH-PX),乳酸脱氢酶(LDH)活性及血清丙二(MAD)含量。结果发现,高原鼢鼠肌肉脂溶性物质提取率为11.5%,共确定了17种成分,主要成分是n-十六烷酸(32.293%),n-十廿烷酸(1.109%),n-十八烷酸(6.03%),二-羟基-环十五酮(1.198%),顺十六烯酸(6.13%),反十八烯酸(27.3%),和亚油酸(81.4%),小鼠抗缺氧实验和生化指标测试结果表明,高原鼢鼠肌从脂溶性成分在20%,10%,5%时,与空白对照组相比,都不同程度地延长小鼠在缺氧条件下的存活时间,提高小鼠血清SOD和GSH-PX活性,降低血清LDH活性,减少血清MDA含量。
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以锂元素标准样品和K、Na、Ca、Mg元素标准样品的混合溶液为主要研究对象,采用阳离子交换树脂AG-50W X8(0.032~0.098 mm粒径)来分离富集Li,探索不同淋洗介质(包括盐酸、硝酸以及与甲醇、乙醇的混合)对Li分离纯化的最佳效果.在对比研究的基础上,建立了一种有效分离提纯天然样品中Li的方法.用本方法分离了水体、土壤、岩石等天然样品中的Li,并用MC-ICP-MS准确测定了Li同位素组成.研究结果表明,该方法的精度在0.1‰~1.0‰,与目前文献报道的分析方法具有相似的精度.经过流程前后单元素标准Li同位素比值(δ^7Li)的比较,发现化学处理过程所产生的同位素分馏约为0.3‰,化学处理的流程空白可以忽略不计.该方法测定海水δ^7Li值为(31.6±1.0)‰,与前人的分析结果吻合.因此,本方法可用于测定天然样品中的Li同位素组成.
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Introduction: Brazil is experiencing a nutritional transition characterized by a reduction in the prevalence of nutritional deficits and an increase in overweight and obesity, not only in adults but also in children and adolescents.Objectives: This study was designed to evaluate the factors associated with overweight and obesity in Brazilian 5-year-old preschoolers.Methods: A cross-sectional study of a cohort of 232 preschoolers born in Diamantina/Minas Gerais, Brazil, was undertaken. the data, including socioeconomic status, anthropometry, diet, previous history of the preschoolers and family history, were collected between July of 2009 and July of 2010. To identify the factors associated with overweight and obesity, a logistic regression and a hierarchical model were undertaken.Results: Overweight and obesity occurred in 17.2% of the preschoolers. After adjusting for mother's obesity, per capita income, protective food intake, weight gain at age 0-4 months and time spent playing, the factors associated with overweight and obesity that reached statistical significance were mother's obesity [OR = 3.12 (95% CI 1.41-6.91), P = 0.01], weight gain of more than 0.85 kg/month in the first four months of life [OR = 2.16 (95% CI 1.01-4.64), P = 0.041 and lower per capita income [OR = 0.32 (95 %CI 0.13-0.79), P = 0.01].Conclusion: the results show that more weight gain during the first four months of life and being born of mothers with obesity increased the odds of overweight/obesity in the preschoolers, while lower per capita income was a protective factor.
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Tod, D., Iredale, F., McGuigan, M., Strange, D., Gill, N. (2005). 'Psyching-up' enhances force production during the bench press exercise. Tod, 19 (3), 599-603. RAE2008
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$u http://books.google.com/books?vid=OCLC02623863&id=mQz8gPn0et8C&a_sbrr=1 View book via Google
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The paper considers a problem of scheduling n jobs in a two-machine open shop to minimise the makespan, provided that preemption is not allowed and the interstage transportation times are involved. In general, this problem is known to be NP-hard. We present a linear time algorithm that finds an optimal schedule if no transportation time exceeds the smallest of the processing times. We also describe an algorithm that creates a heuristic solution to the problem with job-independent transportation times. Our algorithm provides a worst-case performance ratio of 8/5 if the transportation time of a job depends on the assigned processing route. The ratio reduces to 3/2 if all transportation times are equal.
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Portland cement (PC) and blended cements containing pulverized fuel ash (PFA) or granulated blast-furnace slag (GGBS) were used to solidify/stabilize an electroplating sludge in this work. The acid neutralization capacity (ANC) of the hydrated pastes increased in the order of PC > PC/GGBS > PC/PFA. The GGBS or PFA replacement (80 wt%) reduced the ANC of the hydrated pastes by 30–50%. The ANC of the blended cement-solidified electroplating sludge (cement/sludge 1:2) was 20–30% higher than that of the hydrated blended cement pastes. Upon carbonation, there was little difference in the ANC of the three cement pastes, but the presence of electroplating sludge (cement/sludge 1:2) increased the ANC by 20%. Blended cements were more effective binders for immobilization of Ni, Cr and Cu, compared with PC, whereas Zn was encapsulated more effectively in the latter. Accelerated carbonation improved the immobilization of Cr, Cu and Zn, but not Ni. The geochemical code PHREEQC, with the edited database from EQ3/6 and HATCHES, was used to calculate the saturation index and solubility of likely heavy metal precipitates in cement-based solidification/stabilization systems. The release of heavy metals could be related to the disruption of cement matrices and the remarkable variation of solubility of heavy metal precipitates at different pH values.
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This study addresses the long-term stability of three trophic groupings in the Northeast Atlantic at regional scales. The most abundant taxa representing phytoplankton, herbivorous copepods, and carnivorous zooplankton were examined from the Continuous Plankton Recorder database. Multivariate control charts using a Bray–Curtis similarity metric were used to assess whether fluctuations within trophic groupings were within or beyond the expected variability. Two evaluation periods were examined: annual changes between 1960 and 1999 (2000–2009 baseline) and recent changes between 2000 and 2009 (1960–1999 baseline). The trends over time in abundance/biomass of trophic levels were region-specific, especially in carnivorous copepods, where abundance did not mirror trends in the overall study area. The stability of phytoplankton was within the expected limits, although not in 2008 and 2009. Higher trophic levels were less stable, perhaps reflecting the added complexity of interactions governing their abundance. In addition, some regions were consistently less stable than others. Correlations in stability between adjacent trophic levels were positive at large marine ecosystem scale but generally non-significant at regional scales. The study suggests that certain regions may be particularly vulnerable to periods of instability in community structure. The benefits of using the control chart method rather than other multivariate measures of plankton dynamics are discussed.
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After considering museums as cultural institutions responsible for preserving cultural memory and its evolution over time, this article describes the cultural practices within our society that are aimed at disseminating art and at reproducing and transmitting culture, history and identity. Further, it considers the key role that older people are steadily assuming in Spain’s ageing society. New social-empowerment activities based on volunteering by the elderly are linked to generativity because the individual and social groups acquire new skills through those activities, thereby strengthening a society for all ages. Never in the history of social work have so many older people been prepared to participate actively at the community level, and never has a social movement with these features gone so unnoticed by so many social agents.
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Using an experimentally based, computer-presented task, this study assessed cognitive inhibition and interference in individuals from the dissociative identity disorder (DID; n=12), generalized anxiety disorder (GAD; n=12) and non-clinical (n=12) populations. Participants were assessed in a neutral and emotionally negative (anxiety provoking) context, manipulated by experimental instructions and word stimuli. The DID sample displayed effective cognitive inhibition in the neutral but not the anxious context. The GAD sample displayed the opposite findings. However, the interaction between group and context failed to reach significance. There was no indication of an attentional bias to non-schema specific negative words in any sample. Results are discussed in terms of the potential benefit of weakened cognitive inhibition during anxious arousal in dissociative individuals.