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1.
An analytical solution is obtained for the coupled problem of steady-state heat transfer during turbulent flow of a liquid through a plane slot with dissipation of mechanical energy.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 45, No. 3, pp. 392–398, September, 1983.  相似文献   
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Depression in adolescent girls may result in negative consequences in young adulthood. The Center for Epidemiologic Studies Depression Scale (CES-D) was administered to 1,727 Black and White girls ages 16 to 18 years who participated in the National Heart, Lung, and Blood Institute's Growth and Health Study. Three years later, women in the depressed groups were more likely to be current smokers, had attained a lower level of education, and reported lower self-worth relative to the nondepressed group. Body dissatisfaction, eating concerns, and loneliness were greater in the depressed groups. Relative to Black women, White women who were moderately depressed during adolescence reported more health care services utilization in young adulthood. Prevention efforts for depressed adolescents should be broadly focused to improve young adult outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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\(\mathrm {TiO}_{2}\) thin films used as photocatalysts in environmental applications were studied by beam deflection spectroscopy (BDS) and by atomic force microscopy. A novel multiparameter theoretical model was developed in order to explain BDS experimental data. The fundamental parameters of examined films: thermal diffusivity, thermal conductivity, and charge transport properties such as the value of the energy bandgap, carrier lifetime, concentration, and type of dopants, were obtained as results of the modeling of BDS data. With BDS, we observed that the material’s thermal conductivity and thermal diffusivity depend also on the porosity and the surface roughness of films. Consequently, the photocatalytic performance can be estimated by measuring the thermal diffusivity of films. Furthermore, we found that surface roughness is prone to changes when the film is used as photocatalysts in water purification processes. During the purification process, the roughness decreases and the photocatalytical performance drops. Moreover, it was discovered that the thermal, electrical, and morphological properties of photocatalysts films depend on the support to which the \(\mathrm {TiO}_{2}\) layer is deposited. These complex relations demonstrate that knowledge of fundamental physical parameters is required in order to improve the photocatalytic performance of \(\mathrm {TiO}_{2}\) films. In this view, the BDS measurements offer a tool for noncontact and nondestructive evaluation of thermal and electronic parameters of thin film \(\mathrm {TiO}_{2}\) photocatalysts as demonstrated in this work.  相似文献   
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This study examined the levels of hypnotizability and dissociation in an outpatient sample of 17 normal-weight bulimic women and 20 healthy controls. Bulimic patients were significantly more hypnotizable than controls (pp  相似文献   
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The operational principle and the first application of a novel infrared differential thermal lens spectrometer for optical studies of liquid samples is described. Compared to a conventional double-beam (pump/probe) configuration, the instrumental setup described here offers the possibility to substantially reduce (as much as 30 times) the background signal caused by the absorption of solvent, and hence to achieve improved limits of detection (LOD). Differential thermal lens spectrometry (TLS) with a CO laser as the excitation source was applied to detect tuberculostearic acid and the insecticide Carbaryl, both extracted into CCl4; the corresponding LOD are 200 μg/L and 150 μg/L, respectively. Results of preliminary studies also suggest the potential use of differential TLS for detection of citric acid dissolved in water.  相似文献   
8.
This paper investigates a newly proposed spreading code-set based on the prime code (PC) families referred to as ‘transposed modified prime codes (T-MPC)’ for the enhancement of spectral efficiency of synchronous incoherent optical code-division multiple-access (OCDMA) networks. This code family increased the code-set cardinality up to twice of existing PC families’ size. This also implies that a greater number of users can be accommodated by the network. Since there is no longer a time-shift feature in T-MPC like in conventional modified prime codes (MPC), the code is not predictable and thus even more secure. Since the code structure is similar to MPC, its deployment in a system/network already running MPC will not require hardware modification. Due to the higher code utilization factor of T-MPC, a greater number of users are accommodated under certain bit-error rate (BER) resulting in remarkable improvement in the spectral efficiency (SE) and capacity. The T-MPC compatibility with low-weight energy-efficient MPC construction is also investigated. The BER and SE performances are analyzed and compared with existing code families. The results indicated that the T-MPC employment can improve up to 50% higher spectral efficiency.  相似文献   
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Abstract

A general model that accounts for a combined effect of thermal lensing and photothermal beam deflection was derived. The model enables the estimation of contributions to the measured photothermal signal from each of the two phenomena. Experimental parameters such as modulation frequency, the pump beam diameter, and the position of detector can be optimized using this model in order to minimize the unwanted effects of misalignment or laser pointing instability, and to improve the accuracy of thermal lens and photothermal beam deflection spectrometry.  相似文献   
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RT-qPCR is the gold standard and the most commonly used method for measuring gene expression. Selection of appropriate reference gene(s) for normalization is a crucial part of RT-qPCR experimental design, which allows accurate quantification and reliability of the results. Because there is no universal reference gene and even commonly used housekeeping genes’ expression can vary under certain conditions, careful selection of an appropriate internal control must be performed for each cell type or tissue and experimental design. The aim of this study was to identify the most stable reference genes during osteogenic differentiation of the human osteosarcoma cell lines MG-63, HOS, and SaOS-2 using the geNorm, NormFinder, and BestKeeper statistical algorithms. Our results show that TBP, PPIA, YWHAZ, and EF1A1 are the most stably expressed genes, while ACTB, and 18S rRNA expressions are most variable. These data provide a basis for future RT-qPCR normalizations when studying gene expression during osteogenic differentiation, for example, in studies of osteoporosis and other bone diseases.  相似文献   
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