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271.
BACKGROUND: This study investigated the impact of subjective reports of drowsy driving and non-driving duties on the falling asleep responses and road crash involvement of professional drivers in Crete. An attempt was also made to elucidate other driving parameters, such as freight transportation, which could be potential predictors of risky driving, after controlling for lifestyle patterns. METHOD: A sample of 317 professional drivers was studied through personal interviews. The interview questionnaire included items about sleep and fatigue as contributing factors to falling asleep probability and crash risk. In addition, the drivers reported the type of freight they carried in their last trip, as well as practices such as smoking and alcohol consumption. RESULTS: The first logistic regression analysis showed that the most significant predictors of falling asleep at the wheel were transportation of fruits/vegetables and livestock, non-driving hours of work, insufficient hours of sleep, and smoking. The second logistic regression analysis revealed all the previous items as powerful factors of crash probability, including the transportation of express freight and freezer. IMPACT: The findings of the current study are discussed as they pertain to directions for future studies and for the development of fatigue countermeasures.  相似文献   
272.
The effects of thymol (TOH), thymoquinone (TQ) and dithymoquinone (TQ2) on the reactions generating reactive oxygen species (ROS) such as superoxide anion radical (O2*-), hydroxyl radical (HO*) and singlet oxygen (1O2) were tested using the chemiluminescence (CL) and spectrophotometry methods. All tested compounds acted as scavengers of various ROS. The rate constant of 1O2-dimols quenching by thymol was calculated.  相似文献   
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Waste by-pass cement dust was added in different percentages ranging from 2% to 10% to a standard mix for sewer pipes manufacture, as a substitute for expensive feldspar. It was found that a mix consisting of 45% kaolin, 36% ball clay, 9% grog and 10% by-pass dust and fired at a temperature of 1300 degrees C for 4 h yielded samples that meet the standards. It was possible to reach a water absorption of 4%, a modulus of rupture of 7.8 MPa and a resistance to acids and alkalis conforming with standard values. A test pipe was fabricated by vacuum extrusion using the suggested composition and was found to withstand a hydraulic pressure of 14 MPa for one minute without the appearance of any cracks.  相似文献   
276.
This paper summarises the behaviour of major and trace elements during hydrothermal alteration processes in the Vareilles albite deposit, Saint-Chély d' Apcher area (Lozère, France). Sampling focused mainly on fine- to medium-grained two-mica granite facies surrounding albitite veins in two open pits. The primary chemical variability inherent in sampling parent rock and analytical uncertainties can seriously affect element mobility calculations. Here we present a simple model that allows to discriminate between magmatic and alteration effects and to make a proper evaluation of the chemical changes that have caused the alteration. For this reason, a range of unaltered granites and albitites were sampled to evaluate the degree of parent rock heterogeneity. Duplicate measurements were performed by epithermal neutron activation analysis (ENAA) to obtain a reliable mean concentration for trace elements and to evaluate results reproducibility. ENAA measurements are completed by analysis of major elements by inductively coupled plasma-mass spectrometry (ICP-MS). The enrichment or depletion of an element during alteration, relative to its concentration in fresh parent rock, can be calculated on the basis of the assumed immobility of some elements during the process. In this study, we have assumed Ta as immobile element on the basis for his inert behaviour. The distinct differences in chemical change between altered and unaltered granite suggest the need to consider alteration event as an important parameter in evaluating granitic rocks for nuclear waste disposal.  相似文献   
277.

It has been known since the 1970s that differences exist in the profile of element content in wild-growing mushroom species, although knowledge of the role of mushroom species/families as determinants in the accumulation of diverse element remains limited. The aim of this study was to determine the content of 63 mineral elements, divided into six separate groups in the fruit bodies of 17 wild-growing mushroom species. The mushrooms, growing in widely ranging types of soil composition, were collected in Poland in 2018. Lepista nuda and Paralepista gilva contained not only the highest content of essential major (531 and 14,800 mg kg−1, respectively of Ca and P) and trace elements (425 and 66.3 mg kg−1, respectively of Fe and B) but also a high content of trace elements with a detrimental health effect (1.39 and 7.29 mg kg−1, respectively of Tl and Ba). A high content of several elements (Al, B, Ba, Bi, Ca, Er, Fe, Mg, Mo, P, Sc, Ti or V) in L. nuda, Lepista personata, P. gilva and/or Tricholoma equestre fruit bodies belonging to the Tricholomataceae family suggests that such species may be characterised by the most effective accumulation of selected major or trace elements. On the other hand, mushrooms belonging to the Agaricaceae family (Agaricus arvensis, Coprinus comatus and Macrolepiota procera) were characterised by significant differences in the content of all determined elements jointly, which suggests that a higher content of one or several elements is mushroom species-dependent.

Graphical abstract

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278.
With the rapid development of graphene synthesis and functionalization approaches, graphene and its related derivatives have shown great potential in many applications in material science, including biomedical applications. Several in vitro and in vivo studies clearly showed no definitive risks, while others have indicated that graphene might become health hazards. In this study, we explore the biocompatibility of graphene-related materials with chicken embryo red blood cells (RBC). The hemolysis assay was employed to evaluate the in vitro blood compatibility of reduced graphene, graphene oxide, and reduced graphene oxide, because these materials have recently been used for biomedical applications, including injectable graphene-related particles. This study investigated structural damage, ROS production and hemolysis of chicken embryo red blood cells. Different forms of graphene, when incubated with chicken embryo RBC, were harmful to cell structure and induced hemolysis.  相似文献   
279.
Environmental Science and Pollution Research - Agriculture faces many challenges such as climate change, droughts, and salinity, which requires urgent interventions for fast adaptation and...  相似文献   
280.
Food and Environmental Virology - Pig’s blood and liver are valuable edible slaughter by-products which are also the major ingredients of offal-derived foodstuffs. The aim of the study was an...  相似文献   
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