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81.
Urban part of Seine River serving as drinking water supply in Paris can be heavily contaminated by Cryptosporidium spp. and Giardia duodenalis. In the absence of agricultural practice in this highly urbanized area, we investigated herein the contribution of treated wastewater to the microbiological quality of this river focusing on these two parasites. Other microorganisms such as faecal bacterial indicators, enteroviruses and oocysts of Toxoplasma gondii were assessed concurrently. Raw wastewaters were heavily contaminated by Cryptosporidium and Giardia (oo)cysts, whereas concentrations of both protozoa in treated wastewater were lower. Treated wastewater, flowed into Seine River, had a parasite concentration closed to the one found along the river, in particular at the entry of a drinking water plant (DWP). Even if faecal bacteria were reliable indicators of a reduction in parasite concentrations during the wastewater treatment, they were not correlated to protozoal contamination of wastewater and river water. Oocysts of T. gondii were not found in both raw and treated wastewater, or in Seine River. Parasitic contamination was shown to be constant in the Seine River up to 40 km upstream Paris. Altogether, these results strongly suggest that treated wastewater does not contribute to the main parasitic contamination of the Seine River usually observed in this urbanized area.  相似文献   
82.
Metronidazole is one of the first-line treatments for non-severe Clostridium difficile infections (CDI). However, resistance limits its use in cases of severe and complicated CDI. Structure–activity relationships previously described for the 5-nitroimidazole series have shown that functionalization at the 2- and 4-positions can impart better activity against parasites and anaerobic bacteria than metronidazole. Herein we report the synthesis of new 2,4-disubstituted 5-nitroimidazole compounds that show potent antibacterial activity against C. difficile. We used a vicarious nucleophilic substitution of hydrogen (VNS) reaction to introduce a phenylmethylsulfone at the 4-position and a unimolecular radical nucleophilic substitution (SRN1) reaction to introduce an ethylenic function at the 2-position of the 5-nitroimidazole scaffold.  相似文献   
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A simple and robust method to compartmentalize aqueous solutions into an array of independent microchambers is presented. The array of microchambers fabricated in poly(dimethylsiloxane) are filled with the sample solution through a microfluidic channel and then sealed with oil to isolate the microchambers from each other. A water reservoir close to the microchambers allows the maintainance and incubation of sub‐nanoliter solutions (e.g., at 37 °C) within the chambers for hours without any problem of evaporation. Once assembled, the device is self‐sustainable and can be used for different application purposes. As a demonstration, the device configuration is shown to be suitable for spatiotemporal control of the inner solution conditions by light stimulation through a photomask. This method was applied for the generation of regular EmGFP (emerald green fluorescent protein) expression arrays, selective photobleaching, photopatterning of calcium concentration, and cell culture in independent microchambers.  相似文献   
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This study builds on earlier work showing that adult emotional competencies (EC) could be improved through a relatively brief training. In a set of 2 controlled experimental studies, the authors investigated whether developing EC could lead to improved emotional functioning; long-term personality changes; and important positive implications for physical, psychological, social, and work adjustment. Results of Study 1 showed that 18 hr of training with e-mail follow-up was sufficient to significantly improve emotion regulation, emotion understanding, and overall EC. These changes led in turn to long-term significant increases in extraversion and agreeableness as well as a decrease in neuroticism. Results of Study 2 showed that the development of EC brought about positive changes in psychological well-being, subjective health, quality of social relationships, and employability. The effect sizes were sufficiently large for the changes to be considered as meaningful in people's lives. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
87.
The diffusion of water into hardened cement samples containing different kinds of additives has been studied for the first time using nuclear magnetic resonance imaging (NMRI). The results indicate that NMRI can be used as a research and industrial method to evaluate the properties (permeability, durability, etc.) of the final cement product.  相似文献   
88.
Reviews the book, Intercultural Counselling and Assessment: Global Perspectives edited by Ronald J. Samuda and Aaron Wolfgang (1985). Intercultural Counselling and Assessment is an edited volume of papers presented to an invited Symposium on Intercultural Counselling held at Queen's University at Kingston, Ontario, 1983. The intention of the publication, as stated by the editors, was to fill the gap in guidelines and methods in intercultural counselling by providing source material that is both theoretical and practical. The book is geared to professionals in the field of education, psychology, and social work, with the goal of engendering "greater sensitivity and a more professional approach to the task of coping with an increasingly varied and mixed population of students in schools" (p. xvii). The strength of the book lies in its comprehensive coverage. The philosophy of counselling conveyed in the book reflects the orientation of multiculturalism in Canadian immigration policy. Six chapters address the issues and answers in counselling specific ethnic and cultural groups, including Chinese immigrants, South Asian immigrants, West Indian immigrants, European immigrants, Native Canadians, and foreign students. Another six chapters provide the background and guidelines for counselling minorities in specific environments, such as in employment, correctional service, disability service, and education. It is a comprehensive volume and has highlighted the important issues that counsellors should become familiar with in an intercultural society. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
89.
Streamflow in the Ésera and Upper Cinca Rivers (South Central Pyrenees) experiences alterations in the form of rapid pulses, commonly referred to as hydropeaks, associated with highly variable on-demand hydropower production from flowing or stored water. A hydrological characterization of the hydropeaks in these two rivers was carried out to examine their distinct hydropeaking pattern during hydrologically contrasted years. The Ésera demonstrated a hydropeaking regime characterized by a high frequency and magnitude, while the Upper Cinca presented a regime with higher frequency but of lesser magnitude. Additionally, this study classified hydropeaks following the shapes proposed in previous studies and assessed their temporal distribution (frequency), timing, and magnitude. Results indicated that hydropeaks were different in shape and magnitude in both rivers; a Front Step pulse shape dominated in the Ésera whereas a Rectangle pulse shape was the most frequent in the Cinca. The Front Step shape had the highest ramping rates during the rising limb of the hydrograph and the shortest time to the maximum flow; whereas the Rectangle shape had higher duration and a larger volume of water released. Hydropeaks in the Ésera were less frequent (one per day) than in the Cinca (two per day). The river Ésera presented, in general, high-magnitude hydropeaks, with double volume and duration, and three times larger up-ramping rates and time between flow pulses. Overall, hydropeak shapes in the Ésera varied depending on the hydrological year and the season, while in the Cinca, shape distribution followed the same temporal pattern regardless of year and season; thus, hydropeaking in the Ésera appeared to be much more dependent on the annual hydrology (whether the year is wet or dry) than in the Cinca. Hydropeaking regimes were characterized based on three categories of variables: magnitude (flow-based or hydrological variables), timing (duration), and frequency (occurrence). According to the variability of these variables, a total of three statistically significant groups were obtained in the Ésera, while two groups were identified in the Cinca. Hydropeaks can be statistically classified by their hydrological characteristics that in turn may have a direct effect on sediment entrainment and transport with implications to the ecological functioning of rivers. The different shape of the hydropeaks, however, will control the attenuation of the flows downstream and, consequently, the maintenance of the river's competence and capacity. This methodology provides a useful quantification of hydropeaking regimes to assess the potential impacts on physical and biological aspects of river systems.  相似文献   
90.
The development of malignant effusions such as ascites reflects a massive progression of a malignant disease. In patients with ovarian carcinoma, a high amount of ascites (>500 mL) is an independent negative prognostic marker. The composition and constituents of ascites reflect the inflammatory environment of the underlying tumor. Increased cellular resistance of ascites-derived tumor cells and the development of venous thromboembolic events (VTE) are major risks for these patients, especially in patients with advanced ovarian carcinoma. In this study, we discuss the release of tissue factor-bearing extracellular vesicles (TF+ EVs) from tumor cells into the environment (ascites fluid) and their systemic spreading as a possible causal explanation of the pathologic coagulation status in these patients. We obtained ascites from patients with advanced ovarian carcinoma, collected during surgery or therapeutic paracentesis (n = 20). Larger ectosome-like EVs were isolated using sequential centrifugation, quantified by high-resolution flow cytometry and analyzed using nanoparticle tracking analysis. Furthermore, the pro-coagulant properties (TF activity) of EVs were determined. Compared to published TF activities of EVs from healthy persons, TF activities of EVs derived from ascites of patients with ovarian cancer were very high, with a median of 80 pg/mL. The rate of VTE, as reported in the patient files, was high as well (35%, 7 out of 20). Furthermore, all but one patient with VTE had EV concentrations above the median within their ascetic fluid (p < 0.02). Since VTE continues to be a frequent cause of death in cancer patients, prophylactic antithrombotic treatment might be worth considering in these patients. However, given the risk of bleeding, more clinical data are warranted. Although the study is too small to enable reaching a conclusion on direct clinical implementation, it can well serve as a proof of principle and a rationale to initiate a prospective clinical study with different patient subgroups. We also show ex vivo that these larger ectosome-like EVs induce intracellular ERK phosphorylation and tumor cell migration, which is not directly related to their pro-coagulative potency, but might help to understand why cancer patients with thromboembolic events have a poorer prognosis.  相似文献   
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