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741.
Hipólito Amanda Caretta Talita de Oliveira Silveira Victória Akemi Itakura Bersaneti Gabrielly Terassi Mali Suzana Celligoi Maria Antonia Pedrine Colabone 《Journal of Polymers and the Environment》2021,29(10):3199-3209
Journal of Polymers and the Environment - Sophorolipids are glycolipid biosurfactants produced by the yeast Starmerella bombicola. They have great potential for application in the food industry due... 相似文献
742.
Maria Grazia Gnoni Gianni Lettera 《Journal of Loss Prevention in the Process Industries》2012,25(3):609-616
A close relationship between near-miss events and major accidents has been demonstrated in major hazard facilities: a near-miss and an accident have often common causes. A near-miss could be defined as a hazardous condition where the event sequence could lead to an accident if it had not been interrupted. An effective Near-miss Management System (NMS) aims to quickly recognize signals from the operational fields in order to apply prevention strategies. As a standard reference model has not yet been developed, the NMS design represents a complex issue. The present paper proposes a critical comparison between two methodologies which could be applied for a near-miss event assessment: a matrix and an index based method. The purpose is to evaluate potentiality and pitfalls of their application as their global efficiency could influence the whole performance of the whole NMS design. An application in a test case of a chemical plant is proposed: results obtained have proved useful in supporting safety management in an effective design of a NMS. 相似文献
743.
Paraskevas Petrou Evangelia Demerouti Maria C. W. Peeters Wilmar B. Schaufeli Jørn Hetland 《组织行为杂志》2012,33(8):1120-1141
This study focused on daily job crafting and explored its contextual determinants and one motivational outcome (i.e., work engagement). Job crafting was conceptualized as “seeking resources,” “seeking challenges,” and “reducing demands.” Participants were 95 employees from several organizations who completed a 5‐day diary survey. As hypothesized, we found a 3‐factor structure for the job crafting instrument, both at the general and day levels. We hypothesized and found that the combination of high day‐level work pressure and high day‐level autonomy (active jobs) was associated with higher day‐level seeking resources and lower day‐level reducing demands. Furthermore, we found that day‐level seeking challenges (but not resources) was positively associated with day‐level work engagement, whereas day‐level reducing demands was negatively associated with day‐level work engagement. Findings suggest that job crafting is a daily employee behavior with implications for management practice and future research. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
744.
Although the prevalence of employees working within the same workplace or occupation with their spouse has increased, relatively little research has examined their experiences. On the basis of the boundary and conservation of resources (COR) theories, we argue that higher levels of work–family role integration among work‐linked couples will lead to higher levels of spousal support resources and lower levels of work–family conflict. This will, in turn, lead to lower emotional exhaustion among employees in a work‐linked relationship. Among two samples of employees in a variety of occupations, we found that being in a work‐linked relationship was associated with both higher spousal instrumental support as well as different forms of work–family conflict. The interaction between spousal support and work–family conflict was associated with emotional exhaustion. We discuss the implications of these findings for boundary and COR theories in terms of movement of resources across work–family boundaries and resource relevance in the strain process. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
745.
微型、小型和中型企业创造了巴西的主要财富.但是这些企业却难以遵守环境法律.在这种情况下,清洁生产意义重大;它使得应用简便、廉价、持续的解决方案帮助小企业减少其环境影响、降低雇员的健康和安全风险成为可能.清洁生产战略通过把中心放在减少浪费和损耗上而改善环境条件.在实施清洁生产措施的同时,对一些措施的环境效率和经济可行性进行评估.采用最多的是良好的内务管理等简便措施.良好的内务管理包括业务参数的最优化、程序的标准化、改进买卖系统以及维护、信息和培训程序的最优化.巴西良好的内务管理战略所占的优势表明了对低成本解决方案的优先选择. 相似文献
746.
Katharina Maria Jörger Martin Heß Timea Pamela Neusser Michael Schrödl 《Marine Biology》2009,156(6):1159-1170
Sperm transfer via spermatophores is common among organisms living in mesopsammic environments, and is generally considered
to be an evolutionary adaptation to reproductive constraints in this habitat. However, conclusions about adaptations and trends
in insemination across all interstitial taxa cannot be certain as differences in mode of insemination via spermatophores do
exist, details of insemination are lacking for many species, and evolutionary relationships in many cases are poorly known.
Opisthobranch gastropods typically transfer sperm via reciprocal copulation, but many mesopsammic Acochlidia are aphallic
and transfer sperm via spermatophores, supposedly combined with dermal fertilisation. The present study investigates structural
and functional aspects of sperm transfer in the Mediterranean microhedylacean acochlid Pontohedyle milaschewitchii. We show that spermatophore attachment is imprecise. We describe the histology and ultrastructure of the two-layered spermatophore
and discuss possible functions. Using DAPI staining of the (sperm-) nuclei, we document true dermal insemination in situ under
the fluorescence microscope. Ultrastructural investigation and computer-based 3D reconstruction from TEM sections visualise
the entire spermatozoon including the exceptionally elongate, screw-like keeled sperm nucleus. An acrosomal complex was not
detected. From their special structure and behaviour we conclude that sperm penetrate epithelia, tissues and cells mechanically
by drilling rather than lysis. Among opisthobranchs, dermal insemination is limited to mesopsammic acochlidian species. In
this spatially limited environment, a rapid though imprecise and potentially harmful dermal insemination is discussed as a
key evolutionary innovation that could have enabled the species diversification of microhedylacean acochlidians. 相似文献
747.
Kostadin Ganev Maria Prodanova Dimiter Syrakov Nikolai Miloshev 《Ecological modelling》2009,217(3-4):255
US EPA Models-3 system is used for calculating the exchange of ozone pollution between three countries in southeast Europe. For the purpose, three domains with resolution 90, 30 and 10 km are chosen in such a way that the most inner domain with dimensions 90 × 147 points covers entirely Romania, Bulgaria and Greece.The ozone pollution levels are studied on the base of three indexes given in the EU Ozone Directive, mainly accumulated over threshold of 40 ppb for crops (AOT40C, period May–July), number of days with 8-h running average over 60 ppb (NOD60) and averaged daily maximum (ADM). These parameters are calculated for every scenario and the influence of each country emissions on the pollution of the region is estimated and commented.Oxidized and reduced sulphur and nitrogen loads over the territories of the three countries are also determined. The application of all scenarios gave the possibility to estimate the contribution of every country to the S and N pollution of the others and detailed blame matrixes to be build.Comparison of the ozone levels model estimates with data from the EMEP monitoring stations is made. 相似文献
748.
Within a species, ontogenetic and genetic variation in defensive chemistry can provide the basis for natural selection from
different predator types. The osmeterial chemistry of fifth (last) instar Papilio glaucus caterpillars is known to differ qualitatively from the composition of early instar caterpillars. However, the osmeterial
chemistry of early instar caterpillars has not been thoroughly characterized and may change as the caterpillars undergo their
first three molts. We have used GC/MS to identify a suite of about 50 different terpene compounds in the osmeterial secretions
of P. glaucus caterpillars, and found the relative amounts of these compounds changed significantly with each molt. These quantitative
changes preceded the more dramatic qualitative switch to the production of 2-methylbutyric and isobutyric acids after the
molt to the fifth instar. We also examined the effects of diet and genetic background on the relative quantities of 15 terpenes
present in the secretions of third instar caterpillars. Parentage was found to affect the percentages of many more of the
individual components than did diet, although both exerted an effect. The ontogenetic and genetic variations in the composition
of the osmeterial secretions appear to have an effect on would-be predators. In the laboratory, terpene secretion was found
to discourage attack by ants, whereas the switch from terpene to acid production rendered the caterpillars less palatable
to a larger predator, the green anole. In the field, the presence of functional osmeteria did not seem to dramatically increase
survival in a field study, and only a small, non-significant advantage was seen. Similarly, field data was suggestive that
parentage might affect the likelihood of survival in a natural setting, but the stage of the caterpillar and the field site
significantly affected survivorship. Further studies with greater replicates will be needed to determine whether and to what
extent chemical differences in osmeterial components as well as behavior contribute to differences in outcomes in the field. 相似文献
749.
JC Gaillard Emmanuel A. Maceda Elodie Stasiak Iwan Le Berre Maria Victoria O. Espaldon 《Journal of Coastal Conservation》2009,13(2-3):119-129
The present study investigates into the link between people’s vulnerability in the face of coastal hazards and sustainable livelihoods. It focuses on the town of Borongan in the Philippines and draws on questionnaire-based surveys and focus group discussions. This research shows that local fishermen are often compelled to go out fishing despite pending typhoon or storm surge to sustain the daily needs of their family. Its also demonstrates that the capacity of these people to protect themselves from the threat is constrained by poor and fragile livelihoods. In the event of a crisis, the study argues that people resort to a range of adjustments on their daily life which is rooted in the strength and diversity of their livelihoods. To reduce people’s vulnerability and enhance capacities to face coastal hazards, the study fosters Community-Based Disaster Risk Reduction with special emphasis to sustainable livelihoods. 相似文献
750.
Sarah Caronni Maria Anna Delaria Augusto Navone Pieraugusto Panzalis Nicola Sechi Giulia Ceccherelli 《Marine Biology》2014,161(8):1787-1798
Chrysophaeum taylorii (Pelagophyceae) is an allochthonous benthic microalga recently recorded in the Mediterranean Sea. During summer, the occurrence of C. taylorii is usually visible to the naked eye due to the large amount of mucilage this species produces. Information on the spatio-temporal variability of this species and on the predictability of massive mucilage events is still scarce and requires to define ad hoc managing strategies of major bloom events. The aim of this work was to identify the relevant scales of variation in the abundance of C. taylorii abundance and to estimate the relative recurrence of its blooms, testing the hypothesis that mucilage was dependent on the cell density. The first approach was the identification of the most appropriate sampling procedure to estimate benthic cell abundance of C. taylorii. The second one was the estimation of the magnitude of variation in C. taylorii cell abundance attributable to each of several spatial (areas, sites, zones and replicates) and temporal scales (fortnights and years) in the Marine Protected Area of Tavolara Punta Coda Cavallo (Western Mediterranean Sea). The results indicate fortnight and year as the most relevant scales of variability in the cell abundance of C. taylorii and highlight the unimportance of small spatial scales (zone and replicates) to the species variability. The collected data also evidence the absence of a direct relationship between the cell density of C. taylorii and the production of mucilage. In conclusion, these results indicate that patterns in the cell abundance of C. taylorii vary notably depending on the considered scale and that future investigations on processes affecting its performance will need to consider the relevant scales of variation evidenced. 相似文献