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51.
LiMn2O4 was examined as a cathode material for lithium-ion batteries, working together with a room temperature ionic liquid electrolyte, obtained by dissolution of solid lithium bis(trifluoromethanesulfonyl)imide (LiNTf2) in liquid N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide (MePrPipNTf2), with the formation of a liquid LiNTf2-MePrPipNTf2 system. The Li/LiMn2O4 cell was tested by galvanostatic charging/discharging and by impedance spectroscopy. The LiMn2O4 cathode showed good cyclability and Coulombic efficiency in the presence of 10 wt.% of vinylene carbonate (VC) as an additive to the ionic liquid. The flash point of the LiNTf2-MePrPipNTf2-VC(10%) electrolyte was estimated to be above 300 °C.  相似文献   
52.
A novel broadband rat‐race coupler has been investigated. The coupler utilizes an artificial left‐handed transmission line section for broadband phase response realization. Moreover, a narrowband model of left‐handed section has been shown to prove the couplers equivalent circuit at the center frequency. To broaden the operational bandwidth multisection quarter‐wave transformers have been proposed. The exemplary rat‐race coupler with two‐section impedance transformers has been designed and manufactured. © 2013 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:341–347, 2014.  相似文献   
53.
Crack initiation of ferroelectrics under a cyclic electric field was studied using DCB specimens, which contained through-thickness notches of different lengths. An electric field larger than the coercive field strength of the material was applied and resulted in pop-in of a crack in the direction perpendicular to the field. The length of the pop-in varied with the length of the notch. Finite Element modeling was used to quantify the stresses occurring in the specimen under the application of the electric field. The model took into account the fully coupled ferroelectric and ferroelastic hysteresis behavior. Stress intensity factors were derived from the resulting stress distribution using the weight function method. The results were found to agree well with the experimental data.  相似文献   
54.
We assessed the diagnostic potential of cardiovascular disease-associated microRNAs for the early prediction of gestational diabetes mellitus (GDM) in singleton pregnancies of Caucasian descent in the absence of other pregnancy-related complications. Whole peripheral venous blood samples were collected within 10 to 13 weeks of gestation. This retrospective study involved all pregnancies diagnosed with only GDM (n = 121) and 80 normal term pregnancies selected with regard to equality of sample storage time. Gene expression of 29 microRNAs was assessed using real-time RT-PCR. Upregulation of 11 microRNAs (miR-1-3p, miR-20a-5p, miR-20b-5p, miR-23a-3p, miR-100-5p, miR-125b-5p, miR-126-3p, miR-181a-5p, miR-195-5p, miR-499a-5p, and miR-574-3p) was observed in pregnancies destinated to develop GDM. Combined screening of all 11 dysregulated microRNAs showed the highest accuracy for the early identification of pregnancies destinated to develop GDM. This screening identified 47.93% of GDM pregnancies at a 10.0% false positive rate (FPR). The predictive model for GDM based on aberrant microRNA expression profile was further improved via the implementation of clinical characteristics (maternal age and BMI at early stages of gestation and an infertility treatment by assisted reproductive technology). Following this, 69.17% of GDM pregnancies were identified at a 10.0% FPR. The effective prediction model specifically for severe GDM requiring administration of therapy involved using a combination of these three clinical characteristics and three microRNA biomarkers (miR-20a-5p, miR-20b-5p, and miR-195-5p). This model identified 78.95% of cases at a 10.0% FPR. The effective prediction model for GDM managed by diet only required the involvement of these three clinical characteristics and eight microRNA biomarkers (miR-1-3p, miR-20a-5p, miR-20b-5p, miR-100-5p, miR-125b-5p, miR-195-5p, miR-499a-5p, and miR-574-3p). With this, the model identified 50.50% of GDM pregnancies managed by diet only at a 10.0% FPR. When other clinical variables such as history of miscarriage, the presence of trombophilic gene mutations, positive first-trimester screening for preeclampsia and/or fetal growth restriction by the Fetal Medicine Foundation algorithm, and family history of diabetes mellitus in first-degree relatives were included in the GDM prediction model, the predictive power was further increased at a 10.0% FPR (72.50% GDM in total, 89.47% GDM requiring therapy, and 56.44% GDM managed by diet only). Cardiovascular disease-associated microRNAs represent promising early biomarkers to be implemented into routine first-trimester screening programs with a very good predictive potential for GDM.  相似文献   
55.
Lakes are sensitive to environmental changes and anthropogenic effects; and Lake Balaton, the largest shallow freshwater lake in Central Europe, is no exception. To protect the lake (primarily Keszthely Bay) against elevated nutrient loads, the Kis–Balaton Water Protection System (KBWPS) was constructed as a mitigation wetland at the mouth of the River Zala, the largest tributary of the lake. This research demonstrates the effect of the KBWPS on Keszthely Bay's oligotrophication processes. The concentration values of KBWPS and Keszthely Bay's measured parameters and their stochastic relations were analyzed by applying cluster- discriminant analysis, Wilks' lambda statistics, confirmatory principal component- (PCA), and input–output analyses to 19 parameters from 14 monitoring stations. First, the sampling sites were clustered for each year, showing that when the runoff in the system was low, Keszthely Bay behaved as a separate entity, while in the years with high runoff it rather displayed a similarity to the wetland area of the KBWPS. Secondly, PCA showed that, from the perspective of stochastic relations, changes in the background processes of Keszthely Bay were observed only after the settling of the KBWPS; and that the runoff in the examined years did not have any significant influence on it. Furthermore, the eutrophication processes moved upstream from Keszthely Bay to the hypertrophic area of KBWPS. This study confirms that the effects of the KBWPS – together with other load reduction measures – had a beneficial effect on the oligotrophication of Lake Balaton.  相似文献   
56.
The aim of this research is the characterisation of the oxidation products of several hydrophilic phenols of virgin olive oil (VOO), such as hydroxytyrosol (3,4-DHPEA) and tyrosol (p-HPEA) and, their identification in the product during storage. This work is aimed at finding analytical indicators that can be used both as molecular markers of VOO “freshness” and for the evaluation of the shelf life of the product itself. Two oxidation systems were examined for the oxidation of p-HPEA and 3,4-DHPEA: enzymatic oxidation and Fenton oxidation. Reaction products were different for the two systems and were identified as quinones, dimers, and acids. During the autoxidation process, Fenton reaction oxidation products, but not enzymatic oxidation products, were found in VOO.  相似文献   
57.
58.
Reports on a brief orientation program designed to familiarize new interns with some of the major signs of psychopathology they will encounter and to help bridge gaps in training for individual interns. The orientation consists of four 1-day workshops focusing on the areas of depression, suicide and hospitalization, schizophrenia, and neuropsychological problems. Completing these intensive workshop experiences provides a brief overview of psychopharmacology and a short introduction to the evaluation process of child problems. The workshops are regarded as important both for the interns and the staff. As the interns become more curious and less defensive about beginning their clinical rotations, the staff become less frustrated about handling the interns' anxieties concerning their lack of preparation for the internship year. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
59.
60.
Dark chocolate masses and chocolates were supplemented with viable cells of two bacterial strains Lactobacillus caseii and Lactobacillus paracasei with potential probiotic properties, which were lyophilized in milk. Total number of live bacteria in the lyophilizate was 7.9×109 cfu/g. Sucrose or isomalt and aspartame were used as bulking substances and sweeteners. Sensory attributes of these chocolates were not different from that of traditional chocolates. Calorie value of sucrose-free chocolate was lower by approximately 11.1–14.6% (dependent on their formulation) relative to chocolate sweetened with sucrose. Chocolate, which contains isomalt and aspartame can be consumed by diabetics. Numbers of live L. casei and L. paracasei cells in the examined batches of chocolate were very high and approached 106–107 cfu/g after 12 months of keeping at 4 and 18 °C. Neither the texture nor the total and volatile acidity of chocolate masses were changed by addition of the lyophilized preparation of Lactobacillus cells. Casson yield values of dark sucrose-free chocolate masses supplemented with this lyophilizate were decreased by approximately 3–55% (dependently on fat contents in these masses) as compared to that of analogous chocolate masses sweetened with sucrose.  相似文献   
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