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991.
为了解miR167家族成员的分子特性及其可能互作的靶标在龙眼体胚发生早期的调控机制,采用生物信息学分析方法进行龙眼miR167基因家族序列分析、二级结构预测、分子进化树分析、靶基因预测及其靶标特异表达的FPKM值分析,并采用实时荧光定量PCR技术(quantitave real-time PCR,qPCR)检测miR1...  相似文献   
992.
应用接触电位差理论和高斯定理,分析了电除尘器收尘极板上沉降粉尘粒子与极板间的双电层现象,继而探讨了两者间的接触粘结力,建立了粘结力与物质材料电子逸出功的关系。研究表明,紧密接触的沉降粉尘粒子与极板间的接触粘结力与它们各自的电子逸出功之差成正比。这一粘结力是阻止微细粉尘脱离收尘极板的一个重要因素。  相似文献   
993.
椒江口海域重金属含量分布及在沉积物和生物体中的富集   总被引:8,自引:2,他引:6  
研究了椒江口海水、沉积物和生物体中7种重金属的浓度水平,评价了各种重金属在沉积物和生物体内的富集情况.结果表明,表层海水中重金属Cr、Cu、Pb、Cd、Zn、As和Hg的平均浓度分别为0.57、7.37、1.89、0.18、36.99、1.57、0.018μg·L-1;表层沉积物中重金属Cr、Cu、Pb、Cd、Zn、As和Hg的浓度分别为30.11、30.62、32.61、0.106、68.56、2.48、0.027×10-6;生物体内除了鲻鱼中未检出Zn外,七种重金属在缢蛏、鲻鱼体内均有检出,且缢蛏中重金属含量明显高于鲻鱼体内重金属的含量.Cr、Cu、Pb、Zn、As在沉积物中富集系数高于生物体内,Cr、Zn、Hg、Pb在鲻鱼中的富集系数大于缢蛏中.  相似文献   
994.
While strengthening public–private interplay is expected to improve the climate profile of urban planning in terms of mitigation and adaptation, less is known about the practice of such new interactive modes of governing. The paper critically examines the role, benefits and limitations of extended public–private interplay in developing a new housing district in Sweden. The developer dialogue between municipal officials and property developers confirms mutual interests, shared understandings and the added value of interacting. However, the closer the dialogue comes to settling agreements, the more difficult it gets for municipal officials to steer the process and its outcomes in favor of climate proofing. Complications with adapting to the new interactive setting means that municipal officials balance between acting as facilitators and/or regulators and property developers between acting as partners, competitors and/or defenders. Refining steering-strategies for sustaining commitments and securing formal agreements are pertinent for using public–private interplay to climate-proof urban planning.  相似文献   
995.
The contemporary work environment is characterized by an ongoing trend to embed employees in teams because of their expected abilities for handling complex tasks and integrating diverse sets of knowledge and skills. However, leveraging this potential is endangered by stimuli within and outside of teams that take a toll on cohesion and teamwork among team members. Understanding the role that stressors and demands play in the work-related functioning of teams and their members is therefore an increasingly important challenge in the organizational behavior literature. Whereas research on stressors and demands has primarily focused on the individual level, we expand the research scope by considering these phenomena to be multilevel. We perform an interdisciplinary review of the literature on these stimuli in teams and show how related research, such as that on destructive leadership, may benefit from a more balanced account and integration of frameworks on stressors. Our multilevel review is informative for the literature on stressors and demands at the individual and team levels, as it offers an important conceptual grounding for how and why various stimuli in this social environment differentially influence both the collective entity and its individual team members.  相似文献   
996.
The purpose of this study was to examine the pattern of urinary protein excretion induced by 3 consecutive days of wildland firefighting. Eighteen male active-duty military personnel served as the participants. All testing on the 3 consecutive days was conducted at a Northwestern USA fire camp. All participants consumed military-based foods containing 2620–2864?kcal/day. The work activity was evaluated with an accelerometer in association with body weight and hydration markers over the experimental period. Urinary samples were collected pre and post workshift on days 1 and 3 to assess glomerular and tubular protein excretion (total protein, albumin, β2-microglobulin, N-acetyl-β-d-glucosaminidase and creatinine). The urinary levels of glomerular and tubular protein were not significantly different. The main findings of the present study indicate that similar alterations of urinary protein composition can be observed over consecutive days of wildland firefighting, which appears to be dependent on intensity rather than total work output.  相似文献   
997.
Rewilding has been an increasingly popular tool to restore plant–animal interactions and ecological processes impaired by defaunation. However, the reestablishment of such processes has seldom been assessed. We investigated the restoration of ecological interactions following the reintroduction of the brown howler monkey (Alouatta guariba) to a defaunated Atlantic forest site. We expected the reintroduction to restore plant–animal interactions and interactions between howlers and dung beetles, which promote secondary seed dispersal. We estimated the number of interactions expected to be restored by the reintroduction to provide the baseline interaction richness that could be restored. We followed the reintroduced howler monkeys twice a week for 24 months (337 hours total) to assess their diet. We used howler monkey dung in secondary seed dispersal experiments with 2484 seed mimics to estimate the removal rates by dung beetles and collected the beetles to assess community attributes. We compared the potential future contribution of howler monkeys and other frugivores to seed dispersal based on the seed sizes they disperse in other areas where they occur. In 2 years, howler monkeys consumed 60 animal-dispersed plant species out of the 330 estimated. Twenty-one dung beetle species were attracted to experimentally provided dung; most of them were tunnelers, nocturnal, and large-sized (>10 mm). On average 30% (range 0–100%) of the large seed mimics (14 mm) were moved by dung beetles. About 91% of the species consumed by howlers (size range 0.3–34.3 mm) overlapped in seed size with those removed by dung beetles. In our study area, howler monkeys may consume more large-seeded fruit species than most other frugivores, highlighting their potential to affect forest regeneration. Our results show reintroductions may effectively restore ecological links and enhance ecological processes.  相似文献   
998.
A sensitive and specific method for the determination of propineb and its metabolites, propylenethiourea (PTU) and propylenediamine (PDA), using gas chromatography with flame photometric detection (GC-FPD) and LC–MS/MS was developed and validated. Propineb and its metabolite residue dynamics in supervised field trials under Good Agricultural Practice (GAP) conditions in banana and soil were studied. Recovery of propineb (as CS2), PDA and PTU ranged from 75.3 to 115.4% with RSD (n = 5) of 1.3–11.1%. The limit of quantification (LOQ) of CS2, PDA and PTU ranged from 0.005 to 0.01 mg kg?1, and the limit of detection (LOD) ranged from 0.0015 to 0.0033 mg kg?1. Dissipation experiments showed that the half-life of propineb in banana and soil ranged from 4.4 to 13.3 days. PTU was found in banana with a half-life of 31.5–69.3 days, while levels of PDA were less than 0.01 mg kg?1 in banana and soil. It has been suggested that PTU is the major metabolite of propineb in banana. The method was demonstrated to be reliable and sensitive for the routine monitoring of propineb and its metabolites in banana and soil. It also serves as a reference for the detection and monitoring of dithiocarbamates (DTCs) residues and the evaluation of their metabolic pathway.  相似文献   
999.
Based on a review of the history of the employee engagement construct and its measurement, we define workforce engagement as the aggregate of the work engagement experiences of individual employees in an organization. In contrast to most research on employee engagement, we study companies rather than individuals and the companies represent a diverse set of industries. We hypothesize and demonstrate on a sample of (up to) 102 publicly traded companies that workforce engagement significantly predicts organizational financial (adjusting for industry: Return on Assets, Net Margin but not Tobin's q) and customer metrics (the American Customer Satisfaction Index and the Harris Reputation Quotient) 1 and 2 years after the workforce engagement data were collected. In addition, using a split‐sample approach to avoid method bias, we hypothesize and show that (a) company organizational practices (the strongest correlate), supervisory support, and work attributes are significant correlates of workforce engagement and (b) that workforce engagement mediates the relationship between these correlates of engagement and the organizational performance metrics. Implications of the findings for research and practice are discussed.  相似文献   
1000.
为了解决目前国内现有工亡率数据所存在的局限性问题,引入我国工伤保险数据,并在此基础上分析2006—2016年我国及各地区的工亡率变化趋势, 进而运用泰尔指数分析法测算全国及各地区的工亡率地区差异。研究结果表明:2006—2016年,我国总体工亡率呈下降趋势,但整体水平仍偏高;西部明显高于东、中部,但东、中、西部之间的工亡率差异在缩小;东部、中部和西部内部各省市之间的差异还比较大。最后,提出设定管控工亡率指标时要注重追求本质上的进步,各地应采取措施解决不平衡的问题,完善标准化工亡报告制度,选择更高水平的国际对标体系。  相似文献   
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