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1.
During the winter of 1988/1989, the relationships between the prevalence of work-related health and indoor climate complaints and a number of building, management, workplace and personal characteristics have been investigated in a study in more than 60 office buildings located throughout the Netherlands. To collect the information, a questionnaire was prepared on health and indoor climate complaints and personal and workplace characteristics. A checklist was used to obtain information on building characteristics More than 7000 questionnaires were completed by the regular users of the buildings investigated. The results showed that the prevalence of symptoms was higher in air-conditioned buildings than in naturally or mechanically ventilated buildings. some other variables were also related with most work-related complaints after adjustment for selected management, personal, workplace and job characteristics. These included gender, work satisfaction in general, presence of allergies and/or respiratory symptoms, and personal control over temperature at the workplace. No differences were found in symptom prevalences between buildings with spray and steam humidification. The combination of air-conditioning and humidification did not lead to further increases in the prevalence of complaints as compared to buildings with only airconditioning or only humidification. 相似文献
2.
Oxidative Stress Imaging: Visualizing Oxidative Cellular Stress Induced by Nanoparticles in the Subcytotoxic Range Using Fluorescence Lifetime Imaging (Small 23/2018) 下载免费PDF全文
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The product form results recently published for stochastic Petri nets are combined with the well-known product form results for queueing networks in the model formalism of queueing Petri nets yielding the class of product form queueing Petri nets. This model class includes stochastic Petri nets with product form solution and BCMP queueing networks as special cases. We introduce an arrival theorem for the model class and present an exact aggregation approach extending known approaches from queueing networks. 相似文献
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Thin composite layers (tin in plasma polymer matrix) were prepared in a stainless steel vacuum chamber. An RF powered magnetron with tin target was used to excite the discharge and to activate the monomer species (n-hexane). The gas mixture introduced comprised Ar and n-hexane vapours. The properties of the films and chemical composition were characterized by AFM (surface morphology), TEM and Electron tomography (bulk structure characterization), XPS and FTIR spectroscopy (chemical composition analyses). Current-voltage characteristics were measured to examine the electrical properties of the layers and their dependence on the deposition parameters. 相似文献
6.
Aaron Gidding Yuma Matsui Thomas E. Levy Tom DeFanti Falko Kuester 《Future Generation Computer Systems》2013,29(8):2117-2127
The broad adoption of diagnostic and analytical techniques in the field of archeology, presents a unique opportunity for e-Science in the form of scientific explanation, drawing from methodologies aimed at recording, archiving, analyzing, and disseminating, rich data collections to create the needed infrastructure for both research and web-based curation and data management system. This paper presents a needed stepping stone towards synergy between information technology and archeology, by introducing a data acquisition, tagging and characterization pipeline along with a novel method for spatially querying archeological data. 相似文献
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We compared the published cuticular hydrocarbon (CHC) profiles of 78 ant species across 5 subfamilies. Almost 1,000 CHCs have
been described for these species, composing 187 distinct homologous series and ten hydrocarbon groups. In descending order
of occurrence were: n-alkanes > monomethylalkanes > dimethylalkanes > alkenes > dienes>> trimethylalkanes>> methylalkenes > methylalkadienes > trienes
> tetramethylalkanes. Odd chain lengths and positions of methyl or double bonds at odd carbon numbers were far more numerous
than even chain-length compounds or bond positions. Although each species possess its own unique pattern of CHCs, we found
no association between CHC profile and phylogeny. The production of the biosynthetically complex compounds (e.g., methyl branched
dienes) by the most primitive living ant suggests that the basic genetic architecture required to produce the rich diversity
of CHCs was already present prior to their adaptive radiation. Unlike the ubiquitous n-alkanes and monomethylalkanes, there is a huge diversity of species-specific dimethylalkanes that makes them likely candidates
for species and nest-mate discrimination signals. 相似文献
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Numerous recent studies have correlated cuticular hydrocarbon profiles with a wide range of behaviors, particularly in social
insects. These findings are wholly or partly based on multivariate statistical methods such as discriminate analysis (DA)
or principal component analysis (PCA). However, these methods often provide limited insight into the biological processes
that generate the small differences usually detected. This may be a consequence of variability in the system due to inadequate
sample sizes and the assumption that all compounds are independent. A fundamental problem is that these methods combine rather
than separate the effects of signal components. By using cuticular hydrocarbon data from previous social insect studies, we
showed that: (1) in 13 species of Formica ants and seven species of Vespa hornets, at least one group of hydrocarbons in each species was highly (r
2 > 0.8) correlated, indicating that all compounds are not independent; (2) DA was better at group separation that PCA; (3)
the relationships between colonies (chemical distance) were unstable and sensitive to variability in the system; and (4) minor
compounds had a disproportionately large effect on the analysis. All these factors, along with sample size, need to be considered
in the future analysis of complex chemical profiles. 相似文献
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