Grain boundary and Se diffusion investigations in CdSe-CdTe thin-film photovoltaics

Cadmium telluride (CdTe) solar cells are a very attractive thin-film photovoltaic technology because of low-cost manufacturing and high light absorption coefficient. Electron hole pairs generated by photons absorbed in the solar cell have a finite lifetime, due to radiative or nonradiative recombination processes. One path towards increasing the efficiency of CdTe solar cells is to minimise non-radiative recombination at grain boundaries. This work aims to com bine cathodoluminescence (CL) contrast (optoelectrical properties) and electron backscatter diffraction (structure properties) to investigate the effect of grain boundary misorientation on non-radiative recombination. At the range between 35°-55° misorientation angle, the CL contrast was significantly high, which indicates that those regular grain boundaries are strong non-radiative recombination centres. For coincident site lattices (CSL) such as Σ3, Σ5, Σ7 and Σ9 which have high symmetry, the CL contrast was much smaller, which means those special grain boundaries are not harmful to the device. The reduced recombination velocity was also measured, and the results shown to be consistent with the contrast measurements. Se diffusion from CdSe to CdTe by using standard and bevel cross-sections has also been investigated for two samples with different external quantum efficiency (EQE) and thicknesses (i.e. 100 and 400 nm) of the CdSe layer. The results showed that both devices have voids at the inter-diffusion layer, although for the 400 nm CdSe sample voids were more numerous. Rapid diffusion of Se along the CdTe grain boundaries led to small grains at the interface region, due to Kirkendall voids and solute pinning of the grain boundaries, which resulted in a lower EQE for the 400 nm CdSe device. Transmission electron microscopy (TEM) diffraction patterns confirmed a zinc blende cubic structure throughout the absorber layer, which suggests that the lower EQE is not due to a change in the crystal structure, as has previously been reported in the literature. The Se diffusion coefficient is calculated using scanning TEM energy dispersive X-ray (EDX). The diffusion coefficient measured is 7.2×10−12 cm2/s, which is an order of magnitude smaller than the literature value

Utility of vest high frequency chest wall oscillation device versus flutter device in acute exacerbation of chronic obstructive pulmonary disease

Background: Objectives to assess the effectiveness of high frequency chest wall oscillation (HFCWO) vest system and Flutter devices in the treatment of patients with AECOPD, and to compare the efficacy of HFCWO vest system versus Flutter devices.Methods: We conducted an interventional study on 108 out of 129 patients presented with AECOPD, recruited from two-university hospitals. They were classified into three groups, HFCWO group (n=37), Flutter group (n=35), and control group (n=36). The HFCWO group and Flutter group were treated with AECOPD medications in addition to either HFCWO or Flutter physiotherapy, three sessions per week, for four weeks, while control group was treated by medications only. All patients were evaluated before and after treatment by spirometry, ABG, CAT score, and the BODE index.Results: Post treatment assessment for both HFCWO and Flutter groups demonstrated that most of spirometric indices (FEV1%, FVC%, FEV1/FVC %), oxygenations parameters (PaO2, SaO2 %) and CAT score, were significantly improved (p 0.05).Conclusions: Both vest HFCWO and Flutter device are highly effective in treatment of patients with AECOPD in terms of improvement in ventilatory function and oxygenation parameters with better exercise tolerance

Anesthetic considerations for robot-assisted gynecologic and urology surgery

Robotic surgery was first conceived by the United States military in the 1980s. It rapidly developed in both complexity and utility and, in the early 21st century, modern robotic surgery for gynecologic and urologic surgery gained approval in the United States. Today, an ever-increasing number and variety of surgical procedures enlist robotic-assistance. Numerous anesthetic considerations for robotic surgery exist. A few of the most important aspects of conducting a safe anesthetic include: investigating the patient’s co-morbid conditions, realizing the risks associated with the robotic equipment, and positioning the patient with care. This manuscript reviews the current literature on robotic-assisted surgery for gynecologic and urologic procedures with emphasis on history, marketplace, type, variety, and expansion of surgery in these fields. The review focuses on practical considerations for the anesthesiologist caring for patients undergoing robotic surgery. Preoperative, intraoperative and postoperative issues are explored in detail. The rapid expansion of robotic surgery worldwide requires thoughtful consideration of the technique’s weaknesses and associated risks. This review provides a roadmap to adequately prepare anesthesiologists for care of gynecologic and urologic patients undergoing robot-assisted surgery

Synthesis, Characterization, And Antibacterial activity Of Mn (II),Fe(II),Co(II),Ni(II),Cu(II),Zn(II),Cd(II),and Hg (II) Mixed- Ligand Complexes Containing Furan-2-carboxylic acid And (1,10-phenanthroline)

The research includes the synthesis and identification of type mixed ligand complexes of M+2 Ions using Furan-2-carboxylic acid( C5H4O3) (FCA H) as a primary ligand and 1,10-phenanthroline (phen )as secondary ligand.The resulting products were found to be solid crystalline complexes' which have been characterized by :Melting points, Solubility, Molar conductivity. determination the percentage of the metal in the complexes by flame(AAS), magnetic susceptibility, Spectroscopic Method [FT-IR and UV-Vis]. The proposed structure of the complexes using program , chem office 3D(2006) . The general formula have been given for the prepared mixed ligand complexes [M(FCA)2(phen)2] M(II) - Mn (II) , Fe (II),Co(II) ,Ni(II),Cu (II), Zn(II) , Cd(II), and Hg (II). Phen = 1,10-phenanthroline = (C14H8N2.H2O)    The results showed that the deprotonated ligand (Furan-2-carboxylic acid (FCA H) to (Furan-2-carboxylate ion (FCA -)  by using (KOH) coordinated to metal ions as a monodendate  ligand through the oxygen atom of the carboxylate group (-COO-),and the retention of ? (C-O-C) band of the (FCA -) ring at 1224 cm-1 oxygen atom of the ring cm-1 indicates that is not taking part in coordination. Keywords : Furan 2-carboxylic acid; 1,10-phenanthroline;mixed ligand complexes ,    heterocyclic aromatic compound

Magnitude of behavioral deficits varies with job-related chlorpyrifos exposure levels among Egyptian pesticide workers.

Chronic occupational exposure to organophosphorus pesticides (OPs) is consistently associated with deficits on behavioral tests when compared to unexposed comparison groups. However, a dose-response relationship has yet to be established, leading some to doubt an association between occupational OP exposure and behavioral deficits. Pesticide application teams in Egypt who are primarily exposed to one OP, chlorpyrifos (CPF), were recruited into a field assessment. Trail Making A and the more challenging Trail Making B tests were administered to 54 engineers (who supervise the pesticide application process, usually from the side of the field), 59 technicians (who guide the pesticide applicators in the field), 31 applicators (who mix and apply pesticides using knapsack sprayers), and 150 controls (who did not work in the fields) at two different times during the OP application season as well as immediately after applications had ended and 1.5 months later. All participants were males since only males work on pesticide application teams in Egypt. Urinary levels of 3,5,6-trichloro-2-pyridinol (TCPy), a specific metabolite of CPF, confirmed the pattern of lower to higher CPF exposures from engineers to technicians to applicators, and these were all greater than urinary metabolite levels in controls. A consistent relationship between job title and performance speed on the behavioral task was observed: Controls had the best (fastest) performance on Trail Making A and B tests throughout the application season, and applicators had significantly slower performance than engineers on Trail Making A (p = 0.015) and B (p = 0.003). However, individual urinary TCPy, blood acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) levels did not predict individual performance. This study identifies a dose-related effect based on job title, which serves as a surrogate for chronic exposure in that differing job titles exhibit varying group exposure levels. The results establish that chronic occupational exposure to chlorpyrifos is neurotoxic and suggest that the classic biomarkers of recent CPF exposure are not predictive of chronic exposure effects

Synthesis, spectral and antimicrobial activity of mixed ligand complexes of Co(II), Ni(II), Cu(II) and Zn(II) with Anthranillic Acid and Tributylphosphine

Mixed ligand complexes of bivalent metal ions, viz; Co(II), Ni(II), Cu(II) and Zn(II) of the composition [M(A)2((PBu3)2]in(1:2:2)(M:A:(PBu3).  molar ratio, (where A- Anthranilate ion ,(PBu3)= tributylphosphine. M= Co(II),Ni(II),Cu(II) and Zn(II). The prepared complexes were characterized using flame atomic absorption, by FT-IR, UV/visible spectra methods as well as magnetic susceptibility and conductivity measurements. The metal complexes were tested in vitro against three types of pathogenic bacteria microorganisms: (Staphylococcus, Klebsiella SPP .and Bacillas)to assess their antimicrobial properties. Results. The study shows that all complexes have octahedral geometry; in addition, it has high activity against tested bacteria. Based on the reported results, it may be concluded that.The results showed that the deprotonated ligand(nthranilc acid ) to anthranilate ion (A-) by using (KOH) coordinated to metal ions as bidentate ligand through the oxygen atom of the carboxylate group (-COO-), and the nitrogen atom of the amine group (-NH2), where the Tributylphosphine coordinated as a monodentate through the  phosphor atom.   Keywords :Mixed(anthranilic acid or tributylphosphine) complexes, spectroscopy studies, mixed ligands  and  Antibacterial Activitie

The Effect of E-Activities via Learning Management System (Blackboard) in Developing the Skills of Digital Storytelling and Learning Satisfaction among Female Students of Taibah University

The study aimed at measuring the effect of e-activities via learning management system Blackboard in the development of the skills of digital storytelling, and hence at measuring learning satisfaction with using it. The study employed quasi experimental design, and was conducted during the first semester of the academic year (1436- 1437 H); on a population consisted of (37) female students of College of Computer Science and Engineering, at Taibah University. The study sample was divided into two groups: control group consisted of (20) female students, and experimental one consisted of (17) female students. To achieve its goals the study constructed the following: a list of digital storytelling skills, e-activities about digital storytelling, observation card of digital storytelling skills and learning satisfaction scale, and all of them were prepared by the researchers. The results of the study showed that there were statistically significant differences between the mean scores of the control group and the experimental group in the skills of digital storytelling, in favour of the experimental group. The results also showed that there was a high level of learning satisfaction among the female students to be learned using e-activities via learning management system Blackboard

Comparison Study of Axial Behavior of RPC-CFRP Short Columns

In this paper, the axial behaviors of reactive powder     concrete (RPC) short  columns confined with carbon fiber reinforced polymer (CFRP) were   investigated. All the specimens have square cross section of 100 mm × 100   mm and length of 400 mm with aspect ratio 4. The experimental work consists   of three groups. The first group consists of six specimens of RPC with 2% micro steel fiber, without ordinary reinforcing steel and confining by zero, one and two layer of CFRP respectively. The second group consists of six    specimens of RPC with 2% micro steel fiber and minimum ordinary reinforcing  steel and confining by zero, one and two layers of CFRP respectively. The third  group consists of four specimens of RPC without micro steel fiber and ordinary  reinforcing steel and confining by one and two layers of CFRP respectively.  Experimental data for strength, longitudinal and lateral displacement and  failure mode were obtained for each test. The toughness (area under the curve) for each test was obtained by using numerical integration. The RPC columns confined with CFRP showed stiffer behavior compared with RPC columns without CFRP. The ultimate load of the RPC columns with 2% micro steel  fiber + two layers of CFRP + minimum ordinary reinforcement were more than that of the RPC columns with 2% micro steel fiber + minimum ordinary   reinforcement and without CFRP by about 1.333. 

Salivary Interleukin 6 is A Valid Biomarker for Diagnosis of Osteoporosis in Postmenopausal Women

Background: Interleukin 6 (IL6) is pro-inflammatory cytokine associated with decline in ovarian function during menopause which is involved in the pathophysiology of postmenopausal bone loss. Objective: To investigate validity of salivary IL6 as a biomarker to diagnose osteoporosis in post-menopausal women. Patients and Methods: This cross sectional study was conducted on 75 postmenopausal women. Bone mineral density (BMD) was measured by dual energy x-ray absorptiometry (DXA) to diagnose osteoporosis. Salivary IL6 was measured for all postmenopausal women by using Human ELISA kit. Results: Of a total 75 individual involved in the study, 25 were healthy postmenopausal women, 25 had osteopenia, and 25 had osteoporosis. There was no statistical significant differences between age and body mass index in all groups (p>0.05). Mean level of salivary IL6 was significantly different among healthy controls, osteopenic group, and osteoporotic group (11.66 ± 4.44 vs 14.51 ± 6.5 vs 23.9 ±5.52 pg/ml; p<0.001) respectively. The mean salivary IL-6 was significantly higher in osteoporosis group (23.9 pg/ml) compared to control group (11.66 pg/ml). Salivary IL-6 was a valid parameter to predict osteoporosis in postmenopausal woman (ROC area=0.91, p<0.001).Salivary IL-6 showed positive strong significant linear correlation with bone t- score (r=0.62,     P<0.001). Salivary IL6 at the optimum cut off value ≥19.45 pg/ml has highest accuracy (81.3%) to diagnose osteoporosis in postmenopausal women  with sensitivity was 84.%, specificity 80 %, positive predictive value (PPV) at pretest probability 50% was 80.8%,  and PPV at pretest probability 90% was 97.4 %,  and  negative predictive value (NPV) at pretest  probability 10% was 97.8 %. Conclusions: Salivary IL6 was a simple, easy, and a valid biomarker to diagnose osteoporosis in postmenopausal women with high accuracy. This may indicate a hopeful measure for early diagnosis and treatment of osteoporosis. Keywords: Salivary IL6, Menopause, Proinflammatory cytokines, Osteoporosis

Cytotoxic Effect of Aqueous Extract of Anastatica hierochuntica L. on AMN-3 Cell Line in vitro

Anastatica hierochuntica L. is distributed throughout Arabain Peninsula, and elsewhere it is locally called "Kuffe Maryam" .All parts of the plant are used in folk medicine. This study amid to investigate the effect of aqueous extract of anastatica hierochunctica L. on the cancer cell lines AMN-3. Anti cancer activity of aqueous extract of  anastatica hierochunctica L. showed anticancer activity against AMN-3  cell line for twelve  concentrations (0.04, 0.09, 0.195, 0.39, 0.78, 1.56, 3.125, 6.25, 12.5, 25, 50, 100) mg/mL  in comparison with negative control. Keywords: Anastatica hierochuntica L., Cytotoxic activity