The circuit point of view of the temperature dependent open circuit voltage decay of the solar cell

The open circuit voltage decay (OCVD) technique has been used to determine the minority carrier lifetime. In this study, an experimental and analytical method is described for determination of minority carrier lifetime at porous Si based solar cell by photo induced OCVD technique. The cell is illuminated by a monochromatic light source (λ = 658 nm) in the open circuit configuration, and the decay of voltage is measured after abruptly terminating the excitation. For the analysis of the OCVD characteristic of solar cell device, equivalent electrical circuit has been proposed in which the diffusion capacitance is connected in series with the contribution of the solar cell interface. Exact minority carrier lifetimes at low (50-170 K) and high (190-330 K) temperature regions have been obtained as 28.9 and 2.65 μs from the temperature dependent OCVD measurements by using an alternative extraction technique.     

Ab initio Modelling of Plasmons in Metal-semiconductor Bilayer Transition-metal Dichalcogenide Heterostructures

Two-dimensional transition-metal dichalcogenides (TMDs) have attracted enormous interest, due to the richness of their optical and electronic properties. Here, we consider two prototypical two-dimensional TMD metal-semiconductor bilayer heterostructures, VSe₂-MoSe₂ and VSe₂-WSe₂, and investigate the effect of the semiconducting layer on the plasmons supported by the metallic layer using first principles time-dependent density functional theory (TDDFT) calculations. We focus on the flat region of the plasmon dispersion, where momentum transfer is larger than 0.05 Å⁻¹ and the interband transitions gain importance. With the addition of the semiconducting layer, we show that the electronic band structure undergoes significant changes close to the Fermi level, and hybridization occurs, which leads to strengthening of the interband transitions and a significant redshift in the plasmon energy.     

Replantation in children

BACKGROUND: The morphological demonstration and classification of rare tumor types occurring in the region of the head and neck may involve a number of problems. PATIENT AND METHODS: In the following the exceptional case of a plexiform ameloblastoma located in the main nasal cavity is presented. The morphological peculiarities of this locally destructive tumor are revealed by light and electron microscopy. RESULTS: The light microscopic investigations show one-layered epithelial units which are interlinked in a plexiform manner and extend as far as up to the surface epithelium. The electron microscopic investigations show solid and loosened areas. The organelles are well developed, their number varied; rough endoplasmic reticulum is scarce. Glycogen incorporations occur regularly. The tumor cells are connected with a number of desmosomes. The cell surface is characterized by microvilli. CONCLUSIONS: The combination of different methods of investigation is sometimes justified for diagnostic purposes. Especially electron microscopic studies may serve to demonstrate decisive structural peculiarities to classify a certain tumor type. Complete surgical removal is recommended. Postoperative radiation is generally advisable.     

Finite element modeling of the AP1000 nuclear island for seismic analyses at generic soil and rock sites

The AP1000 is a standard design developed by Westinghouse and its partners for an advanced nuclear power plant utilizing passive safety features. The design has been certified by the US Nuclear Regulatory Commission based on their review of seismic analyses at hard rock sites. The plant has five principal building structures: the nuclear island, the turbine building, the annex building, the diesel generator building and the radwaste building. The nuclear island consists of the containment building (the steel containment vessel and the containment internal structures), the shield building and the auxiliary building. These structures are founded on a common basemat and are collectively known as the nuclear island. This paper describes shell and stick finite element models used in fixed base dynamic analyses for the hard rock design certification using the general purpose finite element program ANSYS. It describes a coarser shell model developed for use in soil structure interaction (SSI) analyses. This model is developed in both ANSYS and the soil structure interaction (SSI) program SASSI. Results of the three types of models from ANSYS analyses are compared for a hard rock site. Results are also compared between the ANSYS and SASSI analyses for the same model.     

When can employees have a family life? The effects of daily workload and affect on work-family conflict and social behaviors at home.

This article presents a longitudinal examination of antecedents and outcomes of work-to-family conflict. A total of 106 employees participating in an experience-sampling study were asked to respond to daily surveys both at work and at home, and their spouses were interviewed daily via telephone for a period of 2 weeks. Intraindividual analyses revealed that employees' perceptions of workload predicted work-to-family conflict over time, even when controlling for the number of hours spent at work. Workload also influenced affect at work, which in turn influenced affect at home. Finally, perhaps the most interesting finding in this study was that employees' behaviors in the family domain (reported by spouses) were predicted by the employees' perceptions of work-to-family conflict and their positive affect at home. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Avoidance coping strategies moderate the relationship between self-efficacy and 5-year alcohol treatment outcomes.

Both self-efficacy and coping strategies are important determinants of functioning for substance use disorder patients, yet little is known about their interrelationship. This study examined the relationship between abstinence self-efficacy and cognitive components of coping (positive reappraisal, cognitive avoidance) for male participants (n = 2,596) from 15 residential substance use disorder treatment programs who were assessed at treatment entry, discharge, and 5-year follow-up. Cognitive avoidance coping moderated the effects of self-efficacy on alcohol use at 5 years, whereas positive reappraisal coping was largely unrelated to outcomes. Specifically, for patients with low self-efficacy, reliance on avoidance coping strategies was associated with poorer alcohol use outcomes, but as self-efficacy increased, the negative influence of avoidance coping strategies diminished. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Synthesis and antimicrobial activity of some novel 2,5- and/or 6-substituted benzoxazole and benzimidazole derivatives

A new series of 2,5- and/or 6-substituted benzoxazoles (7a-f), benzimidazoles (8a-g) holding cyclohexyl or cyclopentyl moieties at position 2 and 5- or 6-substituted-2-cyclohexylaminomethylbenzoxazoles (9a, b) was synthesized in order to determine their antimicrobial activities and feasible structure-activity relationships. The synthesized compounds were tested in vitro against three Gram-positive, two Gram-negative bacteria and the yeast Candida albicans in comparison with several control drugs. Microbiological results showed that the synthesized compounds were possessing a broad spectrum of antibacterial activity against the tested microorganisms. 5-Chloro-2-(2-cyclohexylethyl)benzimidazole (8g) was found as the most active compound against the screened Gram-positive bacteria strains at a minimum inhibitory concentration (MIC) value of 12.5 microg/ml. However, it exhibited lower antibacterial potency than the compared control drugs. On the other side, compounds 7-9 indicated significant antibacterial activity against the Gram-negative enterobacter Pseudomonas aeruginosa having MIC values of 50 microg/ml, providing either the same effect as tetracycline or higher activity than streptomycin, but showing less potency than the compared control drug gentamycin. Moreover, the synthesized compounds also possessed antimycotic activity against the yeast C. albicans showing MIC values between 25-50 microg/ml.     

An application of the interaction matrices method for slope failure susceptibility zoning: Dogankent settlement area (Giresun, NE Turkey)

Large-scale instability phenomena frequently occur in slopes in such geologically complex areas as Dogankent in NE Turkey. This study presents an application of the interaction matrices (IM) methodology, as a semi-qualitative method sensitive to large-scale slope instability. For both rock and soil slopes, the main interactive factors were distance from faults, degree of weathering and slope angle. Using IM, a slope failure susceptibility map was created for the Dogankent area and checked again field evidence. The results indicated that IM could be a useful method for slope stability assessment.      

Target recognition in SAR images using radial Chebyshev moments

In this study, a new algorithm for classification of ground vehicles from standard synthetic aperture radar (SAR) images is proposed. Radial Chebyshev moment (RCM) is a discrete orthogonal moment that has distinctive advantages over other moments for feature extraction. Unlike invariant moments, its orthogonal basis leads to having minimum information redundancy, and its discrete characteristics explore some benefits over Zernike moments (ZM) due to having no numerical errors and no computational complexity owing to normalization. In this context, we propose to use RCM as the feature extraction mechanism on the segmented image and to compare results of the fused images with both Zernike and radial Chebyshev moments. Firstly, by applying different threshold target and shadow parts of each SAR images are extracted separately. Then, segmented images are fused based on the combination of the extracted segmented region, segmented boundary and segmented texture. Experimental results will verify that accuracy of RCM, which improves significantly over the ZM. Ten percent improvement in the accuracy is obtained by using RCM and fusion of segmented target and shadow parts. Furthermore, feature fusion improves the total accuracy of the classification as high as 6%.     

HPLC analysis of eluted monomers released from dental composites containing bioactive glass

Objectives: The aim of the present study is to evaluate the released residual monomers from composite resins that contain different proportions of bioactive glass (BAG). Methods: Experimental resin composites were prepared by a resin matrix (50% BisGMA and 50% TEGDMA) and inorganic filler with BAG (5, 10 and 30%). Each resin composite was placed in the tooth cavity (n = 5). After polymerisation, samples were immediately immersed in 75% ethanol and 25% deionised water (6 ml) at 37 °C. Residual monomers (Bis-GMA, TEGDMA, HEMA and UDMA) that were eluted from the composites for 10 m, 1 h, 1 d, 7 d and 30 d were analysed by high-performance liquid chromatography (HPLC). The data were analysed with one-way ANOVA and Tukey HSD at a p < 0.05 significance level. Results: Among the time periods, the fastest released residual monomer was observed in the 10 m elution. The highest amount of released residual monomer from all groups (except the control group) was TEGDMA, whereas this was HEMA for the control group. The amounts of residual monomers eluted from BAG30 were significantly higher than other groups (p < 0.05). Conclusions: The release of the monomer increases in accordance with the increased BAG addition to the composite resins.