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101.
The present study utilizes meta‐analytic techniques to examine the literature on sleep and work performance. In line with previous meta‐analytic research, results indicate that sleep and work performance have a positive relationship. However, more importantly, results from moderator analyses reveal that the type of sleep measurement (sleep quantity and sleep quality), work performance measurement (task performance, organizational citizenship behavior, and counterproductive work behavior), analysis method (between‐person and within‐person), sleep report source (self‐report, other report, and objective), sleep recall window (day, week/month, and more than 1 month), and study setting (field and laboratory) differentially influence the strength of the sleep–work performance relationship. Furthermore, meta‐analytic SEM results indicate that certain mediators (affect, job attitudes, and cognitive resources) provide stronger explanations (i.e., stronger indirect effects) for the relationship between sleep and work performance, depending on the specific type of performance being examined. In general, results highlight the importance of construct operationalization and methodology decisions when conducting sleep–work performance research and provide greater insight into explanations for the relationship between sleep and work performance. Research implications, practical implications, potential limitations, and future directions are also discussed. 相似文献
102.
103.
B. Henderson A. Golub D. Pambudi T. Hertel C. Godde M. Herrero O. Cacho P. Gerber 《Mitigation and Adaptation Strategies for Global Change》2018,23(3):349-369
The objectives of this research are to assess the greenhouse gas mitigation potential of carbon policies applied to the ruminant livestock sector [inclusive of the major ruminant species—cattle (Bos Taurus and Bos indicus), sheep (Ovis aries), and goats (Capra hircus)]—with particular emphasis on understanding the adjustment challenges posed by such policies. We show that market-based mitigation policies can greatly amplify the mitigation potential identified in marginal abatement cost studies by harnessing powerful market forces such as product substitution and trade. We estimate that a carbon tax of US$20 per metric ton of carbon dioxide (CO2) equivalent emissions could mitigate 626 metric megatons of CO2 equivalent ruminant emissions per year (MtCO2-eq year?1). This policy would also incentivize a restructuring of cattle production, increasing the share of cattle meat coming from the multiproduct dairy sector compared to more emission intensive, single purpose beef sector. The mitigation potential from this simple policy represents an upper bound because it causes ruminant-based food production to fall and is therefore likely to be politically unpopular. In the spirit of the Paris Agreement (UNFCCC 2015), which expresses the ambition of reducing agricultural emissions while protecting food production, we assess a carbon policy that applies both a carbon tax and a subsidy to producers to manage the tradeoff between food production and mitigation. The policy maintains ruminant production and consumption levels in all regions, but for a much lower global emission reduction of 185 MtCO2-eq year?1. This research provides policymakers with a quantitative basis for designing policies that attempt to trade off mitigation effectiveness with producer and consumer welfare. 相似文献
104.
Biosynthesis of lipids by Thysanoessa inermis collected from Balsfjorden, northern Norway, in May 1980, was examined in vitro. The highest concentration of lipid within the krill was in the hepatopancreas, and this organ was the most active in esterifying free fatty acids into wax esters. The hepatopancreas (i.e., thoracic contents) incorporated (14C) glucose, (14C) alanine and 3H2O into wax esters, with the fatty alcohol moieties being labelled more than the fatty acids. (14C) fatty acid was incorporated preferentially into the fatty acid moieties of wax esters, this incorporation being markedly stimulated by free fatty alcohol. It is concluded that the fatty alcohols of wax esters are preferentially biosynthesized de novo from dietary protein and carbohydrates, whereas the fatty acids derive preferentially from dietary lipid. On the basis of 3H incorporated from 3H2O, the hepatopancreas in a 50 mg II-group (2 yr old) individual of T. inermis is capable of biosynthesizing de novo, approximately 0.1 mg of lipid (as fatty acids) per day at 5°C. 相似文献
105.
Martin Paulus Monika Altmeyer Roland Klein Armin Hildebrandt Peter Ostapczuk Konstantin Oxynos 《Umweltwissenschaften und Schadstoff-Forschung》1994,6(6):375-383
Ein sinnvoller Einsatz von Akkumulationsindikatoren erfordert zur Qualit?tssicherung neben den vorhandenen Laborstandards
ein anspruchsvolles Probenahmeverfahren, um repr?sentative und reproduzierbate Aussagen über einen Untersuchungsraum treffen
zu k?nnen. Am Beispiel der Regenwürmer wird exemplarisch ein Probenahmeverfahren für landwirtschaftliche R?ume entwickelt
und vorgeführt. Erste Ergebnisse der in den Wurm- und Kotproben gemessenen polyzyklischen aromatischen Kohlenwasserstoffe,
der chlorierten Kohlenwasserstoffe und der Elemente werden dargestellt. Die Schadstoffgehalte der vergleichbaren Wurmproben
belegen, da? es die repr?sentative Probenahmestelle in einem Untersuchungsgebiet nicht gibt. Die Heterogenit?t des Untersuchungsraumes
kann nur durch eine geschichtete Zufallsstichprobe mit einer ausreichenden Anzahl von Einzelproben erfa?t werden. 相似文献
106.
In India, rain water and atmospheric aerosols are observed to bealkaline in nature due to the influence of soil-derivedparticles which are rich in components like Ca and Mg. Thesecomponents increase the neutralization potential of rain waterand have a greater influence at rural site compared to urbansite. However, if there are continuous rains, the concentrationof crustal components becomes lower resulting in lower pH ofrain water. Unlike the characteristics of rain water oncontinent, the pH of rain water has been observed to be acidicin all the events over the Indian Ocean during Pre-campaigns ofIndian Ocean Experiment (INDOEX). The possible reason for acidicrains over Indian Ocean could be the anthropogenic contributionfrom continent transported by NE winds coming towards the oceanduring this period. 相似文献
107.
Sylwia Krzemińska Władysław M. Rzymski Monika Malesa Urszula Borkowska Mariusz Oleksy 《International journal of occupational safety and ergonomics》2016,22(3):350-359
Resistance to permeation of noxious chemical substances should be accompanied by resistance to mechanical factors because the glove material may be torn, cut or punctured in the workplace. This study reports on glove materials, protecting against mineral oils and mechanical hazards, made of carboxylated acrylonitrile–butadiene rubber (XNBR) latex. The obtained materials were characterized by a very high resistance of the produced materials to oil permeation (breakthrough time?>?480?min). The mechanical properties, and especially tear resistance, of the studied materials were improved after the addition of modified bentonite (nanofiller) to the XNBR latex mixture. The nanocomposite meets the requirements in terms of parameters characterizing tear, abrasion, cut and puncture resistance. Therefore, the developed material may be used for the production of multifunctional protective gloves. 相似文献
108.
Švec Roman Martinát Stanislav Pícha Kamil Klusáček Petr Knotek Jaroslav Schaefer Justin Calvin Březinová Monika Navrátil Josef 《Environment, Development and Sustainability》2021,23(10):15074-15099
Environment, Development and Sustainability - Our aim is to determine the factors influencing a visitor’s decision to stay in a green accommodation facility. Visitors from six tourist sites... 相似文献
109.
110.
Ecological theory predicts that low productivity systems should have low biodiversity. However, despite the oligotrophic status
of the Gulf of Aqaba (Northern Red Sea) ciliate species richness was unexpectedly high. In addition, phytoplankton, as main
ciliate prey, was made up by only few genera, indicating a significant niche overlap among the grazers. Up to 97% of the ciliates
were from the same taxonomic group and of the same size range, implying very similar food niches. Ciliate diversity was highest
at times of lowest chlorophyll concentrations, during the period of stable abiotic conditions, but relatively high genetic
diversity within the ciliate prey, notably among the cyanobacteria Synechococcus and Prochlorococcus. In the absence of disturbance and with little predation pressure, the alternate explanations for the observed ciliate diversity
are either very fine niche partitioning by the ciliates, or their competitive equivalence resulting in a random assortment
of species immigrating from a larger metacommunity, in accordance with Hubbell’s, (The unified neutral theory of biodiversity
and biogeography. Princeton University Press, Princeton, 2001) neutral model. While the use of species abundance distributions (SAD’s) is far from definitive, the theoretical SAD’s that
best fit the Gulf of Aqaba ciliate data was most often not that expected by neutral theory. 相似文献