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81.
Male infertility is a common health problem that can be influenced by a host of lifestyle risk factors such as environment, nutrition, smoking, stress, and endocrine disruptors. These effects have been largely demonstrated on sperm parameters (e.g., motility, numeration, vitality, DNA integrity). In addition, several studies showed the deregulation of sperm proteins in relation to some of these factors. This review inventories the literature related to the identification of sperm proteins showing abundance variations in response to the four risk factors for male infertility that are the most investigated in this context: obesity, diabetes, tobacco smoking, and exposure to bisphenol-A (BPA). First, we provide an overview of the techniques used to identify deregulated proteins. Then, we summarise the main results obtained in the different studies and provide a compiled list of deregulated proteins in relation to each risk factor. Gene ontology analysis of these deregulated proteins shows that oxidative stress and immune and inflammatory responses are common mechanisms involved in sperm alterations encountered in relation to the risk factors.  相似文献   
82.
Objective: Cognitive models of panic disorder suggest that change in catastrophic misinterpretations of bodily sensations will predict symptom reduction. To examine change processes, we used a repeated measures design to evaluate whether the trajectory of change in misinterpretations over the course of 12-week cognitive behavior therapy is related to the trajectory of change in a variety of panic-relevant outcomes. Method: Participants had a primary diagnosis of panic disorder (N = 43; 70% female; mean age = 40.14 years). Race or ethnicity was reported as 91% Caucasian, 5% African American, 2.3% biracial, and 2.3% “other.” Change in catastrophic misinterpretations (assessed with the Brief Body Sensations Interpretation Questionnaire; Clark et al., 1997) was used to predict a variety of treatment outcomes, including overall panic symptom severity (assessed with the Panic Disorder Severity Scale [PDSS]; Shear et al., 1997), panic attack frequency (assessed with the relevant PDSS item), panic-related distress/apprehension (assessed by a latent factor, including peak anxiety in response to a panic-relevant stressor—a straw breathing task), and avoidance (assessed by a latent factor, which included the Fear Questionnaire–Agoraphobic Avoidance subscale; Marks & Mathews, 1979). Results: Bivariate latent difference score modeling indicated that, as expected, change in catastrophic misinterpretations predicted subsequent reductions in overall symptom severity, panic attack frequency, distress/apprehension, and avoidance behavior. However, change in the various symptom domains was not typically a significant predictor of later interpretation change (except for the distress/apprehension factor). Conclusions: These results provide considerable support for the cognitive model of panic and speak to the temporal sequence of change processes during therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
83.
In order to ensure stable treated water quality and to reduce chemical costs in any treatment plant it is necessary to study and optimize the coagulant dosing control (CDC). This research focused on the affects of coagulant in the integrated membrane (UF & RO) system employed for industrial water production. The dose of coagulant (PACl) might be associated (partly) with the frequency of cleaning in the RO units, and a value of 20 abs/m in the UF permeate is the control of the dosage process. This could suggest that organic fouling is directly and indirectly (inducing biofouling as well) the cause of fouling of the RO membranes. Nevertheless, high doses of PACl could produce scaling of aluminium and, in this work minimizing PACl to prevent operational problems in RO membranes was focused.

The approach involved the study of the treatment processes, determination of the optimum dose of coagulant, evaluation of the removal efficiency of UV and DOC by coagulation. The available data, which comprised monthly/weekly measurements for a period of six years of operation, was studied and analyzed and an attempt was made to draw some conclusions for the plant regarding the coagulant dosage and the link with UV absorbance as control.

The study of the coagulant dosing control revealed that the use of simple and robust online sensors like UV measurement allows an automatic dosing control although this parameter is not found to be sufficient to fully characterize nor predict fouling during membrane operation and there is no link between UV after the UF and the cleaning frequency of the RO. Parameters, as the added value allowed to verify the doses efficiencies in UV and DOC removal. Coagulant dose depends on the level of UV absorbance in the UF permeate and it should never be higher than 20 abs/m to ensure a RO cleaning frequency as long as possible. However, it was found that the target value of 20 abs/m produced substantial over dose of coagulant — 90% of the time – when UV removal is considered only. In the same way, for coagulant doses in excess of 5 mg/L, the additional removal of UV is less than 2.5% per mg coagulant/L, which suggests that the current dose is on the high side.

Furthermore, a coagulant dose in excess of 5 mg/L did not produce significant additional UV removal, and thus a reduction from 14 mg/L (2005 dose) to ca. 7 mg/L could be considered.  相似文献   

84.
水路和水面     
罗德诺霍夫农舍位于奥地利慕维特尔区的偏僻空地上,一对已婚夫妇周末常来此度假。翻修建筑的时候,为更好利用花园,房主和建筑师把原来倾斜的场地修成了台地。场地北边的清水混凝土墙围成一个狭窄的长形水池。房子后方天井的窗户和坐凳是用裸露的混凝土墙建成的。容易引人注意,水生植物在墙上投射下形状不同的影子。水池还具有过滤的功能。在另一头,水流淌过沙砾池底,然后进入地下泳池。一个太阳能水泵把水抽回到过滤池。泳池的四周种着黑刺李树,一棵老樱桃树为池边的观景木台提供了遮荫功能。可循  相似文献   
85.
As part of the ecological risk assessment associated with radionuclides in freshwater ecosystems, toxicity of waterborne uranium was recently investigated in the microcrustacean Daphnia magna over a three-generation exposure (F0, F1, and F2). Toxic effects on daphnid life history and physiology, increasing over generations, were demonstrated at the organism level under controlled laboratory conditions. These effects were modeled using an approach based on the dynamic energy budget (DEB). For each of the three successive generations, DEBtox (dynamic energy budget applied to toxicity data) models were fitted to experimental data. Lethal and sublethal DEBtox outcomes and their uncertainty were projected to the population level using population matrix techniques. To do so, we compared two modeling approaches in which experimental results from F0, F1, and F2 generations were either considered separately (F0-, F1-, and F2-based simulations) or together in the actual succession of F0, F1, and F2 generations (multi-F-based simulation). The first approach showed that considering results from F0 only (equivalent to a standard toxicity test) would lead to a severe underestimation of uranium toxicity at the population level. Results from the second approach showed that combining effects in successive generations cannot generally be simplified to the worst case among F0-, F1-, and F2-based population dynamics.  相似文献   
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88.
Counterfactual thoughts typically take the form of implied or explicit if–then statements. We propose that the multiplicative combination of “if likelihood” (the degree to which the antecedent condition of the counterfactual is perceived to be likely) and “then likelihood” (the perceived conditional likelihood of the outcome of the counterfactual, given the antecedent condition) determine the strength and impact of counterfactuals. This construct, termed counterfactual potency, is a reliable predictor of the degree of influence of counterfactual thinking upon judgments of regret, causation, and responsibility. Through 4 studies, we demonstrate the predictive power of this construct in a variety of contexts and show that it plays a causal role in determining the strength of the effects of counterfactual thought. Implications of counterfactual potency as a central factor of counterfactual influence are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
89.
This study investigated the impact of kilning on α‐amylase, β‐amylase (total and soluble), β‐glucanase and protease activities in buckwheat malt. Common buckwheat (Fagopyrum esculentum) was steeped at 10°C for 12 h, germinated at 15°C for 4 days and kilned at 40°C for 48 h. Moisture content and enzymatic activities were determined throughout the kilning period. Results showed moisture content was reduced from 44% to 5% after 48 h of kilning at 40°C. β‐Amylase was found to exist in a soluble and latent form in buckwheat. Maximum activity of (a) α‐amylase, (b) total β‐amylase, (c) soluble β‐amylase, (d) β‐glucanase and (e) protease activity occurred after (a) 8, (b) 7, (c) 30, (d) 0, and (e) 8 h of kilning, respectively. The final malt exhibited very little β‐glucanase and cellulase activity. Proteolytic activity was low in buckwheat malt when compared to the barley malt control. All enzymatic activities were found to decrease during the kilning stage. Results indicated that after prolonged kilning at 40°C, inactivation of hydrolytic enzymes occurred; two‐stage kilning for shorter periods is recommended. Although, amylolytic activity was low in malted buckwheat, buckwheat malt shows potential as an ingredient for the brewing and cereal industry.  相似文献   
90.
The performance of a multi-slit Integrated Micro Packed Bed Reactor-Heat Exchanger (IMPBRHE) for methanol synthesis from synthesis gas over Cu/ZnO/support commercial catalyst was experimentally investigated from a reaction engineering perspective. Through establishment of a systematic comparison strategy, performance comparison with a laboratory scale tubular Fixed-Bed Reactor (FBR) with three different dilution ratios was made to evaluate the IMPBRHE. The productivity, thermal behavior, activity of body materials, pressure drop and residence time distribution (RTD) of the two reactor types were investigated. The IMPBRHE outperformed the undiluted FBR and gave CO conversions comparable to the diluted FBRs. The main difference is ascribed to superior heat exchange properties of the IMPBRHE, which can improve reactor performance for an exothermic reaction such as methanol synthesis. The results reveal advantages of the IMPBRHE for robust scale up.  相似文献   
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