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181.
The relationship between somatic growth and growth of otoliths of sea bass larvae, postlarvae and juveniles under relatively steady temperature conditions was studied. Larvae were incubated at the constant ambient temperature of 13.5°C, whereas postlarvae and juveniles were reared at a comparatively steady temperature ranging from 18.6 to 20.4°C, with a mean of 19.67°C. The patterns of both somatic and otolith growth were found to be similar. Differentiated data on larvae length and otolith diameters indicated three periods of change in their growth rates. Since temperature was kept relatively steady during the experiment, and larvae fed ad libitum, these periods could be attributed with relative certainty to intrinsic changes which occur during stage-specific periods of growth. The third period of change in both growth rates indicates a specific phase of growth during metamorphosis. The changes in growth rates, as well as the raw time series of the growth of both larval lengths and otolith diameters, may be described by higher order polynomials with a high degree of probability levels. A non-linear relationship between body length and otolith diameters was established, indicating positive allometric growth of otoliths. It was also observed that the coefficient of allometric growth changed at the time estimated for the end of metamorphosis. Thus, a non-linear relationship and changes in the coefficients of allometry should be borne in mind when back-calculating somatic growth from the growth of otoliths.  相似文献   
182.
Radon concentrations in air and geothermal water of the spa pools in Croatia were measured and the average values of 40.3 and 4.5 kBq/m3 were obtained, respectively. Great difference between radon concentrations in pool and spring water was considered as a result of mixing normal and geothermal water in the pool as well as the radon decay. Estimation of an effective dose, received by the personnel in the Bizovac spa, gave the value of 0.27 mSv/y. At the location Stubica, the transfer factor of the radon for air and thermal water in the pool was calculated, and the value of 4.9+/-0.7 x 10(-3) was obtained.  相似文献   
183.
Background: Risky driving is a common cause of traffic accidents and injuries. However, there is no clear evidence of how difficulties in emotion regulation contribute to risky driving behavior, particularly in small post-Soviet countries. The present study aimed to investigate the relationship between difficulties in emotion regulation and self-reported risky driving behavior in a sample of Lithuanian drivers.

Methods: A total of 246 nonprofessional Lithuanian drivers participated in a cross-sectional survey. Difficulties in emotion regulation were assessed using the Difficulties in Emotion Regulation Scale (DERS; Gratz and Roemer 2004), and risky driving behavior was assessed using the Manchester Driver Behaviour Questionnaire (DBQ; Lajunen et al. 2004).

Results: Males scored higher than females in aggressive violations and ordinary violations. Females scored higher for the nonacceptance of emotional responses, whereas males had more difficulties with emotional awareness than females. More difficulties in emotion regulation were positively correlated with driving errors, lapses, aggressive violations, and ordinary violations for both males and females. Structural equation modeling showed that difficulties in emotion regulation explained aggressive and ordinary violations more clearly than lapses and errors. When controlling for interactions among the distinct regulation difficulties, difficulties with impulse control and difficulties engaging in goal-directed behavior predicted risky driving. Furthermore, nonacceptance of emotional responses and limited access to emotion regulation strategies were related to less violations and more driving errors.

Conclusion: Emotion regulation difficulties were associated with the self-reported risky driving behaviors of Lithuanian drivers. This provides useful hints for improving driver training programs in order to prevent traffic injuries.  相似文献   

184.
Purpose. To determine the prevalence of undesirable skin reactions to latex in dental professionals and students of the School of Dental Medicine in Zagreb, Croatia. Methods. Our research included 444 participants, of which 200 agreed to undergo a skin prick test (SPT). All participants answered a questionnaire in which we asked about incidence of skin lesions, duration of occupational exposure to latex, localization of skin lesions and symptoms. Statistical analysis of the questionnaire and test results was then carried out. Results. Of the total 444 participants surveyed, 249 (56.1%) reported lesions on their skin (professionals 64.8%, students 6.1–58.5%). From the questionnaire, 239 (96.0%) respondents reported lesions on the hands and fingers, mostly in the form of erythema (37.0%) and occasional dryness of skin (29.0%). Positive SPT results were found in 14 (7.0%) out of the 200 respondents who underwent the test. Conclusions. While a large number of subjects (56.1%) reported skin lesions when using latex products at their workplace, the SPT test was positive only in 7.0%. The results show that the prevalence of self-reported skin lesions was significantly related to the length of occupational exposure, with a substantial effect size (p?<?0.001; V?=?0.334).  相似文献   
185.
The results of multi-criteria ranking of copper concentrates by their quality, according to their content of useful and harmful components, are presented in this paper. Cu, Ag and Au were taken as useful components, while Pb, Zn, As, Cd, Hg, Bi and Sb were considered as harmful with adequate weight parameters. Considering its specific role in copper metallurgy, sulfur in the concentrate was considered in two scenarios. In the first scenario S was considered as a useful and in the other one as a harmful component. The ranking is done by implementing the PROMETHEE/GAIA method with an additional implementation of the special PROMETHEE V method, using the standard limitations of the heavy metals content in the concentrate. In this way, it is possible to perform an optimization of the input charge for the copper extraction from two aspects. The first aspect covers benefits from the content of useful metals, while the second deals with the protection of the environment, considering the content of harmful components of the charge.Using multi-criteria decision making for the sake of ranking the quality of copper concentrates, as described in this paper, could be considered as a contribution to the methodology of forming the market price of this product.  相似文献   
186.
ABSTRACT

Thirty-five actinobacterial isolates, obtained from button mushroom (Agaricus bisporus) substrates (i.e., compost in different phases of composting, black peat or casing layer) in Serbia in 2014–2016 were tested in vitro against the causal agents of green mold in cultivated mushroom. Out of six most promising isolates, A06 induced 42.4% in vitro growth inhibition of Trichoderma harzianum T54, and 27.6% inhibition of T. aggressivum f. europaeum T77. The novel strain A06 was identified as Streptomyces flavovirens based on macroscopic and cultural characteristics and 16S rDNA sequence and used in mushroom growing room experiments. Actinobacteria had no negative influence on mycelial growth of the cultivated mushroom in compost in situ. Isolate S. flavovirens A06 enhanced mushroom yield significantly, up to 31.5%. The A06 isolate was more efficient in enhancing yield after inoculation with the compost mold T. aggressivum (26.1%), compared to casing mold T. harzianum (8%). Considering disease incidence, actinobacteria significantly prevented green mold in compost caused by T. aggressivum (6.8%). However, fungicide prochloraz-Mn had a more significant role in reducing symptoms of casing mold, T. harzianum, in comparison with actinobacteria (24.2 and 11.8%, respectively). No significant differences between efficacies of S. flavovirens A06 and the fungicide prochloraz-Mn against T. aggressivum were revealed. These results imply that S. flavovirens A06 can be used to increase mushroom yield and contribute to disease control against the aggressive compost green mold disease caused by Trichoderma aggressivum.  相似文献   
187.
Constant and rapid increase in construction and demolition (C&D) waste generation and consumption of natural aggregate for concrete production became one of the biggest environmental problems in the construction industry. Recycling of C&D waste represents one way to convert a waste product into a resource but the environment benefits through energy consumption, emissions and fallouts reductions are not certain. The main purpose of this study is to determine the potentials of recycled aggregate concrete (concrete made with recycled concrete aggregate) for structural applications and to compare the environmental impact of the production of two types of ready-mixed concrete: natural aggregate concrete (NAC) made entirely with river aggregate and recycled aggregate concrete (RAC) made with natural fine and recycled coarse aggregate. Based on the analysis of up-to-date experimental evidence, including own tests results, it is concluded that utilization of RAC for low-to-middle strength structural concrete and non-aggressive exposure conditions is technically feasible. The Life Cycle Assessment (LCA) is performed for raw material extraction and material production part of the concrete life cycle including transport. Assessment is based on local LCI data and on typical conditions in Serbia. Results of this specific case study show that impacts of aggregate and cement production phases are slightly larger for RAC than for NAC but the total environmental impacts depend on the natural and recycled aggregates transport distances and on transport types. Limit natural aggregate transport distances above which the environmental impacts of RAC can be equal or even lower than the impacts of NAC are calculated for the specific case study.  相似文献   
188.
An investigation carried out in 11 dairies in Serbia has shows that 78.75 % of whey, a by-product of cheese industry, is emitted into river systems, thus contributing to the organic pollution of the environment. This pollution can be avoided by processing of whey into food and pharmaceuticals. It is shown that low-temperature regime of whey concentration and fractionation, based on vacuum concentration and diafiltration, preserves whey proteins undenaturated, as proved by differential scanning calorimetry method. Functional native whey proteins based food products, with potentially high immunomodulatory activity, are obtained.  相似文献   
189.
Environmental Science and Pollution Research - According to recent research, even low levels of environmental chemicals, particularly heavy metals, can considerably disrupt placental homeostasis....  相似文献   
190.
The issue of investigations in this study was an application of heterogeneous Fenton-type catalyst, Fe-exchanged zeolite FeZSM5, for the minimization of phenol and overall organic content in the model wastewater. Applied treatment systems included variation of heterogeneous and homogeneous Fenton-type catalyst with and without the assistance of UV irradiation, FeZSM5/H2O2, Fe2+/H2O2/NH4ZSM5, Fe3+/H2O2/NH4ZSM5, UV/FeZSM5/H2O2, UV/Fe2+/H2O2/NH4ZSM5 and UV/Fe3+/H2O2/NH4ZSM5. Processes efficiency was evaluated on the basis of phenol removal, mineralization extent, H2O2 consumption and concentration of iron ions in the bulk after the treatment. By all applied systems, complete phenol removal was achieved in less than 30 min of treatment time. Systems including heterogeneous Fenton-type catalyst showed somewhat lower mineralization efficiency in comparison to the corresponding systems applying homogeneous Fenton-type catalysts and the addition of synthetic zeolite NH4ZSM5. Significantly lower concentration of iron ions in the bulk after the treatment could give these systems, particularly UV/FeZSM5/H2O2, a great advantage over the homogeneous Fenton-type systems.  相似文献   
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