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This study extends research on creativity by exploring the boundary conditions of the creativity–job effectiveness relationship. Building on social exchange theory, we argue that the extent to which employee creativity is related to sales—an objective work effectiveness measure—depends on the quality of leader–member exchange (LMX). We hypothesize that the relationship between creativity and sales is significant and positive when LMX is high, but not when LMX is low. Hierarchical linear modelling analysis provided support for the interaction hypothesis in a sample of 151 sales agents and 26 supervisors drawn from both pharmaceutical and insurance companies. Results showed that sales agents who were more creative generated higher sales only when they had high‐quality LMX. An ad hoc qualitative study provided a more detailed understanding of the moderator role played by LMX. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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During the last few decades, many environmental certification schemes were developed to enhance transparency and traceability within commodity chains. Most of them are transnational schemes, which means that they were created by non-governmental organizations and/or the private sector, independently from governments. This article aims to examine how local certified companies assess the functioning of such private environmental certification. It presents the results of an empirical research about the expectations and satisfaction of certified companies in Lithuania. Empirical data were collected through a survey with 90 companies certified by one of the three major transnational environmental standards: Forest Stewardship Council (FSC) for the forestry and logging, Marine Stewardship Council (MSC) for fishing and aquaculture, and Oeko-Tex for the production of textiles. The results revealed that most companies have adopted these standards quite recently, indicating that it is generally a new trend in Lithuania. The findings suggest that the overall expectations with the standards’ functions, such as sending signals to clients or getting more market share, were higher than the satisfaction in all cases. The main transnational environmental standard adoption motive was the client demand. It turned out, however, that later after the certification procedure the majority of the companies were most satisfied with the market opportunities that opened up. Furthermore, the companies expected certification to operate best as a market-based mechanism; but most satisfactory performance was accredited to the signalling mechanism. Research suggests that certification provides various benefits for the companies, but the expectations might be rather exaggerated.  相似文献   
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Objective

This study aimed to assess the diagnostic yield of prenatal genetic testing using trio whole exome sequencing (WES) and trio whole genome sequencing (WGS) in pregnancies with fetal anomalies by comparing the results with conventional chromosomal microarray (CMA) analysis.

Methods

A total of 40 pregnancies with fetal anomalies or increased nuchal translucency (NT ≥ 5 mm) were included between the 12th and 21st week of gestation. Trio WES/WGS and CMA were performed in all cases.

Results

The trio WES/WGS analysis increased the diagnostic yield by 25% in cases with negative CMA results. Furthermore, all six chromosomal aberrations identified by CMA were independently detected by WES/WGS analysis. In total, 16 out of 40 cases obtained a genetic sequence variant, copy number variant, or aneuploidy explaining the phenotype, resulting in an overall WES/WGS diagnostic yield of 40%. WES analysis provided a more reliable identification of mosaic sequence variants than WGS because of its higher sequencing depth.

Conclusions

Prenatal WES/WGS proved to be powerful diagnostic tools for fetal anomalies, surpassing the diagnostic yield of CMA. They have the potential to serve as standalone methods for prenatal diagnosis. The study highlighted the limitations of WGS in accurately detecting mosaic variants, which is particularly relevant when analyzing chorionic villus samples.  相似文献   
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• Microalgae oil application for biodiesel synthesis is discussed. • Catalytic effectiveness of ferment preparations and chemical catalyst is disputed. • Application of heterogeneous catalysts for biodiesel synthesis is reviewed. • Possibilities of catalyst regeneration is shown. Recently, there is a growing interest in the use of microalga in various fields. Microalgae have properties such as rapid reproduction and high biomass accumulation, and under certain conditions, some are able to accumulate a large amount of oil. However, microalgae oil often contains more free fatty acids than the vegetable oil and is therefore unsuitable for biodiesel synthesis using alkaline catalysts. For this reason, some authors suggest the application of heterogeneous catalysis. A particular interest in the use of immobilized enzymes has developed. Other solid substances can also be used as heterogeneous catalysts are usually metal oxides, carbonates or zeolites. The use of these catalysts results in simpler biodiesel synthesis, especially purification processes, a cleaner end product and a less polluted environment. The molar ratio of alcohol to oil is lower during enzymatic transesterification, and more than 90% ester yield is obtained using a molar ratio of alcohol to oil of 3:1 to 4.5:1. The alcohols do not have a negative effect on the effectiveness of chemical catalysts, so it is possible to use alcohols in molar ratio from 4:1 to 12:1. The optimal temperature of enzymatic process is 30℃‒50℃. An ester yield of more than 95% was obtained in 12‒48 h. Using chemical catalysts, greater than a 95% yield of esters was obtained at higher temperatures in a shorter time. Material costs of enzymatic catalysis can be reduced by reusing the catalysts directly or after regeneration.  相似文献   
5.
This research presents a geographic information systems (GIS)-based method for ecosystem services (ES) potential assessment in a case study for the Lithuanian national territory. The ES potential was assessed for 31 CORINE land-cover classes (CLC2006) together with 31 ES categorized into regulating, provisioning and cultural ES. An expert-based ranking approach using a two-dimensional ES matrix and a geospatial analysis was applied to determine total ES potential, spatial patterns and relations among multiple ES. Results showed that forest areas had the highest potential for ES delivery whereas ES potential in urban areas was lowest. The spatial autocorrelation of regulating and cultural ES were dispersed while provisioning ES were significantly clustered. The principal component analysis (PCA) identified five factors with distinctive geospatial distribution: Factor 1 – forest areas, Factor 2 – aquatic environments, Factor 3 – livestock farming and energy production, Factor 4 – agricultural food production and Factor 5 – mineral extraction sites. The plotting of Factors 1 and 2 accounted for 72.81% of variance and identified three ES bundles composed by specific ES types: Bundle 1 – forest ecosystems, Bundle 2 – marine and freshwater ecosystems and Bundle 3 – mixed provisioning ecosystems. Trade-offs occur between regulating and cultural ES against the provisioning ES crop production and livestock farming. We conclude that the presented ES assessment can support decision-makers in the development of strategies for natural resources management at national and regional level, support the identification of trade-offs and synergies among ES types and foster ES research in Lithuania.  相似文献   
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Eryngium maritimum is a perennial species growing exclusively in a coastal littoral zone both on sand dunes and shingle beach and indicated as declining in Northern Europe. The objective of the present study was to prove the use of nondestructive physiological measurement methods to access physiological status of endangered plants, using E. maritimum as a model species. Plants from two Latvian sites were studied in comparison with other populations in Northern Europe (Estonia, Lithuania, Poland, United Kingdom) to find out if local differences in environmental factors affect vitality of E. maritimum individuals. Noninvasive chlorophyll analysis and chlorophyll a fluorescence measurements were used as indicators of plant physiological status through characterization of various aspects of photochemistry of photosystem II activity. Dynamics and morphology of individuals were investigated for evaluation of clonal growth potential of E. maritimum in natural conditions. Highly fluctuating trend of dynamics of individuals (within 40 groups at two Latvian sites) was established for E. maritimum in natural conditions over a five-year period. Disturbance of individuals lead to formation of new shoots from nodal root meristems. An exponential regression between fluorescence parameters FV/FM and Performance Index and summary monthly precipitation was found indicating that E. maritimum plants had significant tolerance to water shortage together with susceptibility to increased precipitation. Negative correlation between leaf chlorophyll content and more northern localization of individuals was found (r = 0.95 and r = 0.94, for generative and vegetative shoots, respectively). Northern populations of E. maritimum are endangered by high precipitation in conditions of low air temperature, leading to decrease of photosynthetic productivity and overall physiological status. High developmental plasticity at the root level leads to clonal growth and an efficient survival and relatively long life span of E. maritimum individuals. Chlorophyll a fluorescence is a useful method to search for the effect of suboptimal conditions on physiological status of endangered plant species without elimination and disturbance of individuals.  相似文献   
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