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Jasbir Makker,1,2 Danial Shaikh,1,2 Harish Patel,1,2 Siddarth Hanumanthu,1,2 Haozhe Sun,1 Bushra Zaidi,1 Madhavi Ravi,1,2 Bhavna Balar1,2 1Department of Medicine, BronxCare Health System, Affiliated with Icahn School of Medicine at Mount Sinai, Bronx, NY 10457, USA; 2Division of Gastroenterology, BronxCare Health System, Affiliated with Icahn School of Medicine at Mount Sinai, Bronx, NY 10457, USACorrespondence: Danial ShaikhBronxCare Health System, Affiliated with Icahn School of Medicine at Mount Sinai Bronx, 1650 Selwyn Ave, Bronx, NY 10457, USATel +1 718-974-7383Fax +1 718-960-2055Email dshaikh@bronxcare.orgBackground: Colonoscopy, although a low-risk procedure, is not without associated adverse events. The rates of major adverse events such as perforation and bleeding after a colonoscopy are well reported. The rates of minor incidents following a colonoscopy, however, are less well examined. Recently the Centers for Medicare and Medicaid Services (CMS) started public reporting on the quality of outpatient endoscopy facilities by using a measure of risk-standardized rates of unplanned hospital visits within 7 days of colonoscopy.Aim: We intended to record and present the characteristics of our patient population who had an unplanned hospital visit within 7 days after undergoing colonoscopy in an outpatient setting.Methods: This is a retrospective single-center observational study. During the study period of July 2018 to December 2019, we reviewed charts of all patients who returned to the emergency room within a week of undergoing an outpatient colonoscopy. Patient demographics, clinical data and details of colonoscopy were collected and analyzed.Results: Of the 5344 outpatient colonoscopies performed, our post-colonoscopy emergency room visit rate was 1.05% (n=56). The mean age of the participants was 58 years and 55% were male; 32% of our patients reported gastrointestinal symptoms such as abdominal pain or gastrointestinal bleeding. Patients with gastrointestinal symptoms had a higher rate of polypectomies performed (36.4% vs 11.8%, P = 0.04) and reported higher illicit drug use (31.9% vs 5.9%, P = 0.02) compared with those with non-gastrointestinal complaints. After colonoscopy, 41% of the patients reported reasons for emergency room visits that were entirely unrelated to the procedure.Conclusion: Our study highlights that unplanned visits within 7 days of colonoscopy are not necessarily related to the procedure, and those that are, tend to be due to unavoidable patient factors. Hence the CMS measure may not be an accurate determinant of the quality of procedure or facility care delivered.Keywords: colonoscopy, Centers for Medicare and Medicaid Services, CMS, 7-day readmission, adverse events, gastrointestinal symptoms, post-colonoscopy, unplanned visit

In this study, we simulated the performance of solar cells using appropriate optical and electrical parameters for MoX2 compounds. We used the solar cell capacitance simulator software to simulate MoS2-based solar cells with two structures (ZnO/WS2/MoS2 or ZnO/WSe2/MoS2). We investigated the impact of varying the thickness of the MoS2 absorbing layer, doping, temperature elevation, and exploring the effect of the buffer layer on the electrical characteristics of the solar cell, including parameters like open-circuit voltage (Voc), short-circuit current (Jsc), and solar cell efficiency (η). This analysis aimed to provide valuable insights into optimizing the design and performance of MoS2-based solar cells, contributing to advancements in thin-film solar cell technology. [ABSTRACT FROM AUTHOR]

Knowledge of the physical properties of a material is crucial to realising its practical technological applications. In this regard, a study related to phase stability, transition pressure, electronic properties, optical properties, and thermal properties of GaAs, GaN, as well as their mixed ternary alloys GaN0.25As0.75, GaN0.5As0.5 and GaN0.75As0.25 is presented. The study is performed by employing a “full-potential-linearized augmented plane wave plus local-orbital (FP-L(APW + lo)) approach framed within the density functional theory (DFT)” and recognized within WIEN2k computational code. The results of the phase stability show that the GaNxAs1–x alloys are stable for all compositions in the zinc blende phase (B3), except for x = 1, whereas the structure corresponding to the x = 1 composition is found to be more stable in the wurtzite (B4) phase. The physical properties of the more stable phases corresponding to each composition are explored. The pressure-induced phase transition is also investigated, corresponding to each composition. The electronic and optical properties are investigated using the “Tran–Blaha modified Becke–Johnson (mBJ)” potential approach. To explore the thermal properties, the "quasi-harmonic Debye model" approach is employed. Our calculated results of the absorption coefficients and optical band gap show that these alloys could be appropriate candidates for applications in solar cells and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Photovoltaic conversion is a photo-electronic process that involves the interaction between a photo and an electron. The subject is to present a study on the physical principle of operation of a photovoltaic cell based on silicon. The external parameters that we have determined from a photovoltaic model are the short-circuit current (Jsc), the open-circuit voltage (Voc) and the photovoltaic conversion efficiency (), we simulate the photovoltaic parameters by the Solar Cell Capacitance Simulator structures (SCAPS-1D) software whose mathematical model is based on solving the equations of Poisson and continuity of electrons and holes. We used two structures to carry out this study, the first ITO/CdS/Si and the second ZnO/Si/CdS, after having noted their current-voltage characteristic (J-V). In this paper we studied the effect of the temperature and the doping concentration on the two structures of heterojunction solar cell. The highest performance value for the ZnO/CdS/Si heterojunction solar cell was simulated as 29.3 %. The performance value for the ITO/CdS/Si structure was increased to 29.7 % with the impact of the ITO antireflective layer. [ABSTRACT FROM AUTHOR]

Based on the conception of the Cosmos as a grand, created Book consisting of Divine Signs, a conception made possible by the linguistic-conceptual system of the Islamized Arabic, this article [...]

Due to increased energy intensive human activities resulting in accelerated demand for electric power coupled with the occurrence of natural disasters with increased frequency, intensity, and duration, it becomes essential to explore and advance renewable energy technology for the sustainability of the society. To meet the energy demand of the future, more energy resources and energy conversion/harvesting technologies with higher efficiencies are needed. Addressing the problem and providing a radical solution have been attempted in this study. To harvest the renewable energy, among variety of solar cells reported, a composite a-Si/CZTS photovoltaic device has not yet been investigated. The calculated parameters for solar cells based on the new array of layers consisting of a-Si/CZTS are reported in this study. The variation of (i) solar cell efficiency as a function of Cu2ZnSnS4 (CZTS) layer thickness, temperature, acceptor, and donor defect concentration; (ii) variation of the open-circuit current density as a function of temperature, open circuit voltage; (iii) variation of open-circuit voltage as a function of the thickness of the CZTS layer has been determined. There has been no reported study on a-Si/CZTS configuration-based solar cell, analysis of the parameters, and study to address the challenges that imped efficiency of the photovoltaic device and the same has been discussed in this work. The value of the SnO2/a-Si/CZTS solar cells obtained from the simulation is 23.9%. [ABSTRACT FROM AUTHOR]

The I-V-T characteristics of perovskite based solar cells using hybrid organic-inorganic metal halide (CH3NH3PbBr3) as one of the material components have been studied. A numerical simulation has been performed through Solar Cell Capacitance Simulator (SCAPS-1D) software to simulate the perovskite solar cells. Poisson equation and continuity equations for the solar cells have been employed using SCAPS-1D program. The variation of the current density with voltage, current density with temperature, efficiency with defect density, and efficiency and fill factor with rise in temperature of the solar cells has been presented in this study. From the investigations, the perovskite solar cell efficiency of the order of 27.5 % has been obtained at an operating temperature of 270 K. The current density for all temperatures is constant having a value close to 25 mA/cm² until the supply voltage is 1.125 V. The power density increases linearly to a maximum of 27.5 mW/cm². The open circuit voltage and temperature are inversely proportional to each other. The obtained efficiency is 27.54 % at a defect density of 1015 cm–3. [ABSTRACT FROM AUTHOR]

In this work, we have investigated the crystal growth of the CuGaSe2 chalcopyrite structure compound which is intended for tandem photovoltaic devices. Analyses by X-ray diffraction have shown that the obtained ingots are polycrystalline and have a chalcopyrite structure. The preferential orientation along the plane (112) -- very suitable for photovoltaic conversion -- was obtained. The lattice parameters a and c were calculated from the X-ray spectra, the ratio c=a was found to be near to 2. The use of an energy dispersive spectrometer (EDS) for the analysis of the chemical composition of the constituents showed that the investigated sample had a stoichiometric ratio Cu/In = 0:99. The morphological analysis performed using a scanning electron microscope (SEM) has shown that the CuGaSe2 compound has a well-crystallized appearance with an average grain size of about 3 μm. Characterizations by Hall effect measurements and resistivity have shown that the prepared ingot exhibits a p-type conductivity and low resistivity, of the order of 12.73 cm. The measurement of the photoconductivity of the prepared compound has allowed us to determine the value of the gap at room temperature. The gap was found to be near 1.68 eV. The results obtained within the framework of this study have shown that the prepared CuGaSe2 compound has good crystalline and optoelectronic properties, which makes it one of the ideal compounds to be used as the top cell for a tandem photovoltaic device. [ABSTRACT FROM AUTHOR]

Aims: To ascertain the effectiveness of Aspergillus niger, Trichoderma harzianum, Pochonia chlamydosporia, Bacillus subtilis and Pseudomonas fluorescens against rice root‐knot nematode, Meloidogyne graminicola, and to optimize their application methods. Methods and Results: The relative effectiveness of five indigenous biocontrol agents (BCA) against M. graminicola on rice cv. PS‐5 was tested initially in pot culture. The BCAs, A. niger, P. chlamydosporia and P. fluorescens proved more effective, and significantly reduced the nematode disease. It is hypothesized that success of a biocontrol module may vary with the BCA and application methods. Hence, the effectiveness of the above three BCAs as well as seven different treatment schemes were evaluated in naturally infested farmer's fields during 2 consecutive years. In nematode‐infested plots without any BCA treatments, terminal galls formed on the roots, and plants suffered a 19–31% decrease in the growth and yield. The treatments with P. chlamydosporia or A. niger through root‐dip (RD) plus one soil application (SA) at 15 days after planting were found to be highly effective against the nematode. Conclusions: Relatively greater nematode control was achieved with RD plus two SAs (15 + 30 DAP) but statistically the effect was on par with RD + one SA at 15 DAP. These treatments significantly reduced galling (22–25%), egg mass production (21–29%) and reproduction factor (63–70%) of M. graminicola, and subsequently increased the grain yield (11–21%). Significance and Impact of the Study: Application methods enhanced the effectiveness of BCAs against M. graminicola. The RD plus one SA at 15 DAP proved to be most effective treatment to control root‐knot disease in rice. Use of multiple treatments (root dip and SA) appears cumbersome, but in view of effectiveness and limitation of chemical control in rice paddies, farmers may adopt the above module that may lead to 11–21% yield improvement. [ABSTRACT FROM AUTHOR]

The aim of our work was to innovatively design and simulate an InxGa1-xN-based thin-film solar cell which is considered as a promising candidate for high performance solar cells. By inserting SnS, CdS and TCO layers, different cell parameters, such as the efficiency η, the fill factor FF, the current density Jsc, the open circuit voltage Voc and the current-voltage (J--V) characteristics, of four configurations, specifically, InxGa1-xN/SnS/ZnO, InxGa1-xN/CdS/ZnO, InxGa1-xN/In0.5Ga0.5N/ZnO and InxGa 1-xN/SnS/TCO, were investigated. The influence of an SnS, In0.5Ga0.5N and CdS buffer layer on the InxGa1-xN/SnS/ZnO structure and the effect of a TCO layer on the electrical characteristics of the structure were also investigated. It was revealed that the current density increases with the increase in the indium content, however, as the concentration attains a value of 80%, Jcc approximately becomes constant. The no-load voltage Voc was observed to decrease as a function of the indium content (from 50 to 80%), however, it slightly increased for In0.9Ga0.1N and for the binary compound InN. The computed results indicated that the effect of doping concentration and thickness of each layer on the electrical parameters of the InxGa1-xN alloys may result in enhancing the performance of solar cells. [ABSTRACT FROM AUTHOR]

The electrical parameters of the microelectronic devices are limited by the presence of the grain boundaries, including dangling bonds, which can represent states with minority carrier traps. The improvement of photovoltaic efficiency requires a good understanding of the phenomenon of solidification, which varies with temperature. In this work, we study the influence of the annealing temperature and hydrogenation on the electrical conductivity and resistivity. The changes in resistivity as a function of heat treatments show that their overall contribution becomes important with increasing temperature before becoming dominant. The analysis by induced current shows the effect of recombinant grain boundaries and electrical activity. [ABSTRACT FROM AUTHOR]

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Thin film solar cell is a second generation solar cell that is made by depositing one or more thin layers. Debutant analysis of the parameters impeding the efficiency of the CdS/MoS2 heterojunction based photovoltaic device is the chief novelty of the present report. In this work, we investigated the effect of Transparent Conductive Oxide (TCO) utilizing zinc oxide (ZnO) or lead oxide (PbO) antireflective thin film (ARC) on the characteristics of CdS/MoS2 heterojunction solar cell (short circuit current density Jsc, open circuit voltage VCO, power-voltage (P-V) and capacitance-voltage (С-V)). All these options are implemented in the one-dimensional numerical simulation program SCAPS. The results obtained show that as a result of the use of TCO, the short circuit current density Jsc decreases as a function of the applied voltage for both cells. The decrease in the current density is modest below 0.6 V and sharper above. On the other hand, the power density increases almost linearly to a maximum of ~ 3.83 and 3.29 mW/cm2 for ZnO and PbO TCO, respectively. The variation in the capacitance with the voltage is similar to the variation of the current density for both configurations and we found that the efficiency of ZnO coating solar cells is higher than of cells coated with PbO. [ABSTRACT FROM AUTHOR]