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1.
What do health care practitioners need to know about providing adequate care for depressed minority women? This article examined the prevalence of depressive symptoms and clinical depression in ethnic minorities, the extent to which current health service utilization is congruent with needs, and the effectiveness of treatments provided to ethnic minorities in the primary care setting. The impact of ethnic minority women's sociocultural context on symptom expression and help-seeking behavior is also discussed. Finally, the clinical implications for accurate assessment and treatment of ethnic minority women by both medical and mental health practitioners working in the primary care sector are addressed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
The Journal of Supercomputing - Quantum computing is a reality that presents challenges to computer engineering students and practitioners. It has been claimed that it is possible to effectively...  相似文献   
3.
The electrochemical CO2 reduction reaction (CO2RR) to value-added chemicals with renewable electricity is a promising method to decarbonize parts of the chemical industry. Recently, single metal atoms in nitrogen-doped carbon (MNC) have emerged as potential electrocatalysts for CO2RR to CO with high activity and faradaic efficiency, although the reaction limitation for CO2RR to CO is unclear. To understand the comparison of intrinsic activity of different MNCs, two catalysts are synthesized through a decoupled two-step synthesis approach of high temperature pyrolysis and low temperature metalation (Fe or Ni). The highly meso-porous structure results in the highest reported electrochemical active site utilization based on in situ nitrite stripping; up to 59±6% for NiNC. Ex situ X-ray absorption spectroscopy (XAS) confirms the penta-coordinated nature of the active sites. The catalysts are amongst the most active in the literature for CO2 reduction to CO. The density functional theory calculations (DFT) show that their binding to the reaction intermediates approximates to that of Au surfaces. However, it is found that the turnover frequencies (TOFs) of the most active catalysts for CO evolution converge, suggesting a fundamental ceiling to the catalytic rates.  相似文献   
4.
This paper presents a new, simple, accurate, and inexpensive practical methodology and experimental solution for the modeling of conventional (domestic and commercial facilities) photovoltaic generators (PVG), so that they can work at their maximum power point (MPP). The PVG may be a panel, an array of panels, or a photovoltaic field. As a starting restriction (actual) it has to be assumed that it is not possible to isolate the PVG variables dependence (mainly current, voltage, and hence power) with solar radiation and temperature, because they are highly correlated. This methodology proposes the modeling facility on its MPP by its MPP resistance (RMPP = VMPP/IMPP), being VMPP and IMPP the voltage and current of the PVG, respectively, at its MPP. The analysis shows, by simulation first and then experimentally, that RMPP does not present significant temperature dependencies, at least in the usual range. This important result allows us to model the PVG only in terms of solar radiation. From a set of experimental data, different models to estimate RMPP are proposed. The obtained results are very accurate. These models allow an immediate practical application that it is also developed in the paper: MPP tracker (MPPT) design by the calculation of the DC/DC converter duty cycle which places the PVG at its MPP directly and continuously. This new methodology and experimental system has been registered in the Spanish Patent and Trademark Office with the number P201530352. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
5.

Abstract  

n-Butanol dehydrogenation to butyraldehyde was studied using Ru, Cu and Ru–Cu catalysts supported on ceria, titania and zirconia. Among the monometallic Cu and Ru supported catalysts, the non-noble catalytic systems recorded higher conversions and butyraldehyde selectivities than the noble catalysts. Furthermore, the 5Cu/ZrO2 catalyst had the best catalytic activity and selectivity. This behaviour is related to the good metal phase dispersion on the zirconia structure. The addition of Ru reduced this catalyst’s performance because Ru incorporation weakened the Cu-support interaction and favoured the sintering of the Cu metal crystallites.  相似文献   
6.
In this work, we give a complete picture of the behavior of the low intensity bootstrap of linear statistics. Our setup is given by triangular arrays of independent identically distributed random variables and different normalizations related to the rates of bootstrap intensities. We show that the behavior of this low intensity bootstrap coincides with that of partial sums of a number of summands equal to the bootstrap resampling size. Agreement on the limit laws for different (small) bootstrap sizes is thus shown to be closely related to domains of attraction of α-stable laws. As a byproduct, we obtain local distributional properties of Lévy processes.  相似文献   
7.
The acetalization reaction between glycerol and formaldehyde using Amberlyst 47 acidic ion exchange resin was studied. These acetals can be obtained from renewable sources (bioalcohols and bioalcohol derived aldehydes) and seem to be good candidates for different applications such as oxygenated diesel additives. A preliminary kinetic study was performed in a batch stirred tank reactor studying the influence of different process parameters like temperature, feed composition and the stirring speed. A pseudo homogenous kinetic model able to explain the reaction mechanism was adjusted. Thus, the corresponding order of reaction was determined. Amberlyst 47 acidic ion exchange resin showed a fairly good behavior allowing 100% of selectivity towards acetals formation. However, the studied acetalization reaction showed high thermodynamic limitations achieving glycerol conversions around 50% using a stoichiometric feed ratio at 353 K. The product is a mixture of two isomers (1,3-Dioxan-5-ol and 1,3-dioxolane-4-methanol) and the conversion of 1,3-dioxolane-4-methanol into 1,3-Dioxan-5-ol was also observed.  相似文献   
8.
A method for thermodynamic characterization of shape-stabilized phase change materials (PCM) based on one-single sample and one-single experiment has been proposed. The simplicity of the experimental device is comparable to that of the T-History method. However, instead of simple energy balances as in T-History method, a numerical heat transfer model is used to retrieve the whole set of parameters/functions characterizing the PCM from temperature measurements at one-single point within the PCM. An efficient inversion technique has been proposed for that. Its most striking feature is that it allows non-parametric identification of the enthalpy-temperature function in an easy way. Such a function is retrieved by solving a problem of nonhomogeneous heat source term estimation by inversion of a linear heat conduction model.  相似文献   
9.
In this work, we apply statistical modelling techniques to study the influence of increasing concentrations of ethanol on the overall growth of 29 yeast strains belonging to different Saccharomyces and non‐Saccharomyces species. A modified Gompertz equation for decay was used to objectively estimate the noninhibitory concentration (NIC) and minimum inhibitory concentration (MIC) for the assayed strains to ethanol, which are related to the susceptibility and resistance of yeasts to this compound, respectively. A first ANOVA analysis, grouping strains as a function of their respective Saccharomyces species, revealed that S. cerevisiae was the yeast with the highest, and statistically significant, ethanol resistance value. Then, a second factorial ANOVA analysis, using the origin of strains (wild or fermentative) and their taxonomic classification (S. cerevisiae, S. paradoxus or S. bayanus var. uvarum) as categorical predictor variables, showed that no significant differences for the NIC and MIC parameters were found between both ecological niches within the same species, indicative that these physiological characteristics were presumably not modified throughout the adaptation to human‐manipulated fermentative environments. Finally, differences among selected strains with respect to ethanol tolerance were correlated to the initial contents of unsaturated fatty acids, mainly oleic acid. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
10.
OBJECTIVE: Septo-optic dysplasia, which consists of the association of the hypoplasia of the optic nerves and the agenesis of the septum pellucidum, is frequently associated with deficiency of hypothalamic releasing factors. In Magnetic Resonance (MR) of these patients, anomalies in the form and size of the pituitary stalk, adenohypophysis and neurohypophysis are found. Some cases show schizencephaly and it has been proposed as an added component of the syndrome by some authors. This fact has been refuted by others. PATIENTS AND METHODS: We present the clinical and neuroanatomic revision of six children with septo-optic dysplasia studied by MR imaging over the last five years in our Department of Neuropediatrics. The aim was, that through the neuroembryological discussion of the morphopathological aspects of the patients, to determine the malformation and the time in which the injury, which was the underlying cause, occurred. RESULTS: From the six cases, in two only disruptive signs were evident with the optic nerves being affected asymmetrically, disruption of the corpus callosum, falx cerebri indemnity and effects in the cortex conformation. This was opposed to the dysgenic features in the other four cases which had no disruptive features. CONCLUSIONS: Our findings suggest that this entity could be the result of at least two different pathogenic processes, that is, a minor form of holoprosencephaly (dysgenesis) or a disruption which, therefore, occurs later in gestation.  相似文献   
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