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171.
Carabid beetles, like Pterostichus oblongopunctatus, living in metal contaminated areas may be exposed to elevated levels of metals within their diets. However, when compared to other second order consumers, they have one of the lowest observed levels of metals, indicating methods of detoxification to deal with such toxicants. In this study, we investigated if chronic, multigenerational exposure to metals leads to resistance to toxic metal concentrations, and if so, what are the costs associated with them. Adult organisms were collected from two sites, a polluted and a reference site near Olkusz, in southern Poland. These adults were immediately mated, and eggs were collected twice weekly to assess the effects in the larvae of the F(1) generation. Larvae were randomly exposed to one of four artificial mediums: control, 50 mg kg(-1) Cd, 500 mg kg(-1) Zn, and a combined treatment of 50 mg kg(-1) Cd and 500 mg kg(-1) Zn to investigate possible interactions. Individuals were sacrificed at 10, 30, and 40 days. Although metals were not accumulated in larvae (p>0.05), larvae fed the Cd or the Zn treatment grew significantly slower, and had the lowest survival rate (p<0.05) in respect to control. Out of metal treated animals, those on the combined treatment of CdZn grew the quickest and had the highest observed survival (p<0.05). Although previous studies have demonstrated changes in adult population parameters under chronic, multigeneration exposure to toxic metal concentrations, our study did not reveal any changes in the larval stage.  相似文献   
172.
This paper presents the results of a study on changes in 137Cs activity concentrations in three fish species from the southern Baltic Sea: cod (Gadus morhua), herring (Clupea harengus) and flounder (Platichtys flesus), in the period 2000–2010. During the study period a marked decline in cesium activity concentration in fish muscle tissue was observed, which reflected changes in radionuclide activity concentration in seawater. No statistically significant temporal trends were determined in changes of concentration factors (CFfish/seawater) calculated for the examined fish species. The analysis of 137Cs activity as a function of ichthyological parameters revealed the lack of a relationship between radionuclide activity concentrations in herring muscle tissue and the fish age in an narrow age range (2–4 years). However, a reverse proportionality of total fish mass, as well as body length, against 137Cs activity concentrations in muscles was well documented. The latter observation can be the direct result of the dilution effect related to the increase of fish body weight. 137Cs activity concentration in muscle tissue of the five fish species forms a declining sequence: Gadus morhua, Platichthys flesus, Clupea harengus, Perca fluviatilis and Neogobius melanostomus.  相似文献   
173.
Environmental Science and Pollution Research - This article presents a bibliometric study of 200 European publications released between 2001 and 2016, about the contamination of mushrooms by...  相似文献   
174.
Environmental Science and Pollution Research - Endocrine-disrupting chemicals (EDC) are a wide group of chemicals that interfere with the endocrine system. Their similarity to natural steroid...  相似文献   
175.
There is accumulating evidence that maternal hormones may play a role in offspring sex adjustment, but little is known about the costs of such hormone-mediated mechanisms. Recent studies have reported sex-specific effects of hormones on offspring viability. Specifically, we previously found that elevating the plasma androgen level in mothers results in a male-biased offspring primary sex ratio, but it affects the viability of sons negatively and daughters positively in zebra finches (Taeniopygia guttata; Rutkowska and Cichoń, Anim Behav, 71:1283–1288, 2006). In this study, we studied further fitness consequences of exposure to elevated yolk androgen levels in zebra finches. We measured growth rate and cellular immune response of nestlings that hatched from eggs laid by females injected with testosterone during egg laying and nestlings of unaffected control females. We found that sons of testosterone-treated females grew slower in comparison to sons of control females. The significant interaction between experimental group and offspring sex indicates that sons of testosterone-treated mothers suffered impaired immune responsiveness while daughters seemed to benefit from elevated androgen level in terms of enhanced immune responsiveness. We found no effects of androgens on offspring performance at adulthood—neither fecundity of females nor attractiveness of males was affected. We conclude that the benefits of biasing sex ratio towards males by increasing androgen level in the yolk may be limited due to negative effects on male offspring performance early in life.  相似文献   
176.
With the present development of digital registration and methods for processing speech it is possible to make effective objective acoustic diagnostics for medical purposes. These methods are useful as all pathologies and diseases of the human vocal tract influence the quality of a patient's speech signal. Diagnostics of the voice organ can be defined as an unambiguous recognition of the current condition of a specific voice source. Such recognition is based on an evaluation of essential acoustic parameters of the speech signal. This requires creating a vibroacoustic model of selected deformations of Polish speech in relation to specific human larynx diseases. An analysis of speech and parameter mapping in 29-dimensional space is reviewed in this study. Speech parameters were extracted in time, frequency and cepstral (quefrency) domains resulting in diagrams that qualified symptoms and conditions of selected human larynx diseases. The paper presents graphically selected human larynx diseases.  相似文献   
177.
According to the European prestandard ENV 342:1998, the thermal insulation of cold-protective clothing is measured with a thermal manikin. Systematic studies on the reproducibility of the values, measured with different types of clothing on the commonly used standing and walking manikins, have not been reported in the literature. Over 300 measurements were done in 8 different European laboratories. The reproducibility of the thermal insulation test results was good. The coefficient of variation was lower than 8%. The measured clothing should fit the manikin precisely, because poorly fitting clothing gave an error in the results. The correlation between parallel and serial insulation values was excellent and parallel values were about 20% lower than serial ones. The influence of ambient conditions was critical only in the case of air velocity. The reproducibility of thermal insulation test results in a single laboratory was good, and the variation was lower than 3%.  相似文献   
178.
The kinetics of famotidine (FAM) transformation under the influence of various factors, important from the environmental point of view, was investigated in aqueous solutions. The degradation processes using UV, H2O2, UV/H2O2, H2O2/Fe2+, and UV/H2O2/Fe2+ were studied. Direct photolysis and H2O2-assisted photolysis showed a pseudo-first-order kinetics, while the Fenton and the photo-Fenton processes fit second-order kinetics. The provided experiments proved a high resistance of FAM to direct photolysis. Its stability depends highly on the pH of the reaction solutions. The rate of FAM direct photolysis in acidic solutions was almost negligible. The reaction rate of FAM photolysis at pH 8–9 was 3.7 × 10?3 min?1 with DT50 about 3 h 7 min. It was found that the presence of H2O2 in the reaction environment enhances the rate of photolysis of FAM. The observed rates of reaction were 5.1 × 10?3 min?1 and 3.7 × 10?3 min?1 in acidic and basic solutions, respectively. The used Fenton systems appeared to be the most efficient in FAM removal. The rate of reaction depends on concentration of Fe2+ and H2O2. It was observed that the presence of UV-light enhances the reaction rate by two to six times in comparison to the classical Fenton system. Additionally, FAM behavior in natural water under solar irradiation was examined. The irradiation experiments were carried out in batch experiments with simulated sunlight.  相似文献   
179.
An extremely potent mutagen, 3‐chloro‐4(dichloromethyl)‐5‐hydroxy‐2(5/f)‐furanone (MX) is commonly present in chlorinated drinking water. Due to its high mutagenic activity and according to WHO guidelines its concentration should be controlled in drinking waters. Determination of MX is difficult due to ppt levels at which the compound usually exists in drinking waters. Derivatization with 2‐propanol is presented as a method which significantly lowers GC/MS detection level of MX. Suitability of 2‐propylation for derivatization of other hydroxyfuranones is also shown.  相似文献   
180.
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