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We investigated the geometrical and electronic properties of copper-doped MoS2 by first principles calculations. The doping is done by Cu substitution with Mo (1 to 4 atoms) accompanied by study of S vacancies. Our outcomes show that the concentration of doping and vacancy of S leads to determine and finely tune the band gap in the range of 0.16 to 1.95 eV. This fine tuning of band gap results due to variation in concentration of impurity, changing dopant site, and production of S vacancies. The resulting arrangements show significant charge redistribution on replacement of local atoms with foreign atoms dictated by electronegativity determined from the Bader analysis. In addition, bonding mechanism occurring due to substitution of foreign elements is discussed. These results give pleasing data regarding fine desired value of the band gap of the MoS2 which helps its utilization in semiconductor and other opto-electronic devices in addition to understanding the electrical conductivity.

Purpose To test the hypothesis that tolerating some subretinal fluid (SRF) in patients with neovascular age-related macular degeneration (nAMD) treated with ranibizumab using a treat-and-extend (TE intensive arm: SRF intolerant) or resolution of all IRF only (relaxed arm: SRF tolerant except for SRF >200 μm at the foveal center) before extending treatment intervals. A 5-letter noninferiority margin was applied to the primary outcome. Main Outcome Measures Mean change in best-corrected VA (BCVA), and central subfield thickness and number of injections from baseline to month 24. Results Of the 349 participants randomized (intensive arm, n = 174; relaxed arm, n = 175), 279 (79.9%) completed the month 24. The mean change in BCVA from baseline to month 24 was 3.0 letters (standard deviation, 16.3 letters) in the intensive group and 2.6 letters (standard deviation, 16.3 letters) in the relaxed group, demonstrating noninferiority of the relaxed compared with the intensive treatment (P = 0.99). Similar proportions of both groups achieved 20/40 or better VA (53.5% and 56.6%, respectively; P = 0.92) and 20/200 or worse VA (8.7% and 8.1%, respectively; P = 0.52). Participants in the relaxed group received fewer ranibizumab injections over 24 months (mean, 15.8 [standard deviation, 5.9]) than those in the intensive group (mean, 17 [standard deviation, 6.5]; P = 0.001). Significantly more participants in the intensive group never extended beyond 4-week treatment intervals (13.5%) than in the relaxed group (2.8%; P = 0.003), and significantly more participants in the relaxed group extended to and maintained 12-week treatment intervals (29.6%) than the intensive group (15.0%; P = 0.005). Conclusions Patients treated with a ranibizumab T&E protocol who tolerated some SRF achieved VA that is comparable, with fewer injections, with that achieved when treatment aimed to resolve all SRF completely.

Herein, we report thin films&rsquo, characterizations and photovoltaic properties of an organic semiconductor zinc phthalocyanine (ZnPc). To study the former, a 100 nm thick film of ZnPc is thermally deposited on quartz glass by using vacuum thermal evaporator at 1.5 &times, 10&minus, 6 mbar. Surface features of the ZnPc film are studied by using scanning electron microscope (SEM) with in situ energy dispersive x-ray spectroscopy (EDS) analysis and atomic force microscope (AFM) which reveal uniform film growth, grain sizes and shapes with slight random distribution of the grains. Ultraviolet-visible (UV-vis) and Fourier Transform Infrared (FTIR) spectroscopies are carried out of the ZnPc thin films to measure its optical bandgap (1.55 eV and 3.08 eV) as well as to study chemical composition and bond-dynamics. To explore photovoltaic properties of ZnPc, an Ag/ZnPc/PEDOT:PSS/ITO cell is fabricated by spin coating a 20 nm thick film of hole transport layer (HTL)&mdash, poly-(3,4-ethylenedioxythiophene) poly(styrene sulfonic acid) (PEDOT:PSS)&mdash, on indium tin oxide (ITO) substrate followed by thermal evaporation of a 100 nm layer of ZnPc and 50 nm silver (Ag) electrode. Current-voltage (I-V) properties of the fabricated device are measured in dark as well as under illumination at standard testing conditions (STC), i.e., 300 K, 100 mW/cm2 and 1.5 AM global by using solar simulator. The key device parameters such as ideality factor (n), barrier height ( ϕ b ), junction/interfacial resistance (Rs) and forward current rectification of the device are measured in the dark which exhibit the formation of depletion region. The Ag/ZnPc/PEDOT:PSS/ITO device demonstrates good photovoltaic characteristics by offering 0.48 fill factor (FF) and 1.28 &plusmn, 0.05% power conversion efficiency (PCE), &eta

Nitrogen implanted III-V compounds semiconductors have attracted a great deal of attention of the research community due to their interesting fundamental physical properties and potential applications in optoelectronic devices. A small amount of nitrogen incorporation in gallium arsenide (GaAs) causes significant reduction in the band gap energy of fabricated alloys. In this study the GaAsN layer was prepared by implantation of nitrogen ion on thick GaAs wafer and the samples were thermally annealed for studying annealing effects. The structural, compositional and optical properties have been investigated by X-Ray Diffraction (XRD), Rutherford Backscattering Spectroscopy (RBS), Scanning Electron Microscopy (SEM), Photoluminescence (PL) and Photo-thermal Deflection Spectroscopy (PDS). The results reveal that the samples prepared with higher implantation dose and annealed at higher temperature exhibit strong optical signal of GaN, while the samples annealed at lower temperature show weak optical signal. Furthermore in PDS spectra, the band gap reduction was observed indicating the diluted nitrogen content in GaAs. We have demonstrated that annealing conditions and implanted nitrogen doses could be helpful to achieve the desired variation in band gap and low physical damages on surface.

A multilayer system of 10 alternating TiO2 and MgF2 thin film was prepared on BK7 glass substrate by electron beam and resistive thermal evaporation techniques respectively. The substrate with 20 mm diameter and thickness of 1 mm were placed in a vacuum chamber at partial pressures of 10–5 mbar for TiO2 and 10–6 mbar for MgF2 film respectively. The as-deposited films were annealed at 400 °C for an hour in ambient environment. The structural, optical and morphological properties were studied by XRD, UV–vis spectrophotometer, ellipsometery and scanning electron microscopy (SEM) respectively. The structural analysis confirms that all the thin films samples were polycrystalline in nature with tetragonal and rhombohedra phases. SEM analysis confirms the uniformity of surface and quite stable multilayer thin film structure without any micro cracks. Ellipsometery studies were carried out and refractive index and extinction coefficient as function of wavelength are obtained. The samples are found highly transparent in the range of 400–800 nm, whereas the overall absorption and reflection of the multilayer thin film was decreased for the annealed samples. It has been demonstrated that the residual reflectance of the AR coating can be significantly reduced by combining the multilayer systems with an outermost low index layer made of MgF2. The realization of such hybrid multilayer systems are extremely useful as front surface of the photovoltaic cells, optoelectronic devices and front mirror for laser.

To assess changes in vision-related quality of life (VR-QoL) among patients with treatment-resistant neovascular age-related macular degeneration (nAMD) following intravitreal aflibercept treatment over 48 weeks. We conducted a prospective study in which 49 patients with nAMD resistant to anti-vascular endothelial growth factor therapy were switched to intravitreal aflibercept. Patients were treated with three loading doses every 4 weeks followed by injections every 8 weeks, for a total of 48 weeks. Ophthalmic examinations performed at each visit included best-corrected visual acuity (BCVA) and central macular thickness (CMT) measurement. The National Eye Institute Visual Functioning Questionnaire 25 (NEI VFQ-25) was used to assess VR-QoL at baseline and weeks 24 and 48. Changes in NEI VFQ-25 composite and subscale scores were analyzed using paired t tests. The relationship between the change in VR-QoL and changes in BCVA and CMT, and the impact of the better-seeing eye (BSE, defined as the eye reading the greater number of letters at baseline) vs. the worse-seeing eye (WSE, the fellow eye to the BSE) were assessed. Mean NEI VFQ-25 composite scores improved significantly at weeks 24 and 48 compared to baseline (4.5 ± 9.2 and 4.4 ± 11.8, respectively, all p

Here, the structure-dependent electronic, thermal, and transport properties of nanostructured thallium telluride (Tl8Pb x Sb2−x Te6) through controlled variation in Pb and Sb (x = 1.96, 1.97, 1.98, 1.99) concentrations have been investigated. In the temperature and concentration-dependent electrical conductivity measurements, the highest electrical conductivity 131.96 × 103 Ω − 1 m − 1 at 300 K was measured for x = 1.99 and the maximum observed Seebeck value for the optimized Tl8Pb1.96Sb0.04Te6 nanoparticles was 110.7 μV/K at 550 K. Such an increased value of the Seebeck coefficient led to the achievement of a significantly improved high-power factor, which was found to be increasing with temperature and decreasing with the increase of Pb concentration. The density functional theory calculations performed for Pb and Sb co-doped Tl5Te3 resulted in the enhanced σ e and S with a significant reduction in electronic thermal conductivity (κ e ) and is found consistent with experimentally measured κ e . The highest ZT = 0.35 and 0.18 were recorded experimentally and theoretically for Pb and Sb co-doped in Tl5Te3 nanoparticles.

Intravitreal anti-vascular endothelial growth factor (anti-VEGF) agents are the established standard of care for neovascular age-related macular degeneration (nAMD). However, data on long-term outcomes of this therapy are limited. The purpose of this study was to assess the visual and anatomical outcomes and safety profile of intravitreal ranibizumab in treating nAMD over a period of five years. 208 patients (208 eyes) were included in this retrospective case series study. Intervention was an “as-needed” treatment model. Visual acuity (VA), central macular thickness (CMT), ophthalmic examination, and adverse events (AEs) were assessed in each visit. Snellen VA was converted to Early Treatment Diabetic Retinopathy Study letters for analysis. The average VA improved by 1.9 letters after one year (p = 0.017), and decreased by 2.4 letters over five years of treatment (p = 0.043). At the end of year five, 11.1 % of patients (23/208) had improved VA by more than 15 letters and 68.8 % (143/208) had VA improvement or loss less than or equal to 15 letters, while 20.2 % of patients (42/208) had a loss of more than 15 letters. Patients with VA of less than 35 letters at baseline showed significant VA improvement after five years of treatment. There was a positive relationship between injection numbers and VA improvement over the five-year period, after adjusting for age and baseline VA (p

We report the experimental work for the determination of wavelength standard to validate the measurements of Fourier transform spectrometer. A dc run hollow-cathode discharge with two anodes on either sides of a cathode is designed for the p recise measurements of He II lines at 4686 A. The Doppler width and ion-drift shift were measured by using each anode alternatively wh ich changes the direction of electric field fro m 0 o to 180 o . The stability of He II line has been investigated and comparable precision with respect to previous work has been obtained. Excellent wavelength accuracy with relative uncertainty in line position of the order of 10 8 is within reach of single point calibration factor.

Purpose: Retinal ischemia has been traditionally assessed by fluorescein angiography, visualizing perfused vessels. However, this method does not provide any information about nonperfused vessels, and although it is often assumed that vessels in ischemic areas regress, we know little about how nonperfused retinal vessels change over time. Here, we aim to learn more about the long-term fate of nonperfused vessels in the retinal vasculature.\ud \ud Methods: Optical coherence tomography (OCT) was used to visualize perfusion as well as structural properties of the retinal vasculature in patients suffering from retinal vascular occlusions. In addition, postmortem tissue from a patient with long standing (6 years) central retinal vein occlusion (CRVO) was investigated, using immunohistochemistry on whole-mount retina and paraffin sections to visualize blood vessel components.\ud \ud Results: Comparing OCT angiography with enface OCT images revealed that in ischemic areas of the retina, nonperfused, larger vessels could be detected as hyperreflective structures in enface OCT images. Furthermore, analysis of a postmortem tissue sample from a CRVO patient with a large nonperfused region in the macula, revealed preservation of the basement membrane from all retinal vessels, including nonperfused, acellular vessels of all calibers.\ud \ud Conclusions: Our data suggests long-term preservation of vascular basement membrane in ischemic retina. This has implications for therapeutic approaches aiming to alleviate retinal ischemia via the regeneration of damaged vessels.

Thin films of cadmium sulfide with very well defined preferential orientation and relatively high absorption coefficient were fabricated by thermal evaporation technique. The research is focused to the fabrication and characterization of the compositional data of CdS thin films obtained by using X-ray diffraction, scanning electron microscope along with energy dispersive X-ray spectroscopy. The optical properties were studied by using a UV-VIS-NIR spectrophotometer. The effects of silver-doping by ion exchange process on the properties of as-deposited CdS thin films have been investigated.

Purpose: To prospectively assess the safety and efficacy of intravitreal aflibercept for treatment-resistant neovascular age-related macular degeneration (nAMD). Methods: This prospective, non-randomized clinical trial included 49 patients with treatment-resistant nAMD who received 2 mg intravitreal aflibercept as 3 monthly loading doses, followed by injections every 2 months over 12 months. Inclusion criteria included active nAMD on fluorescein angiography at baseline and persistent intra- or subretinal fluid on optical coherence tomography (OCT) for ≥6 months prior to baseline with a minimum of 4 injections of bevacizumab and/or ranibizumab. Patients were assessed monthly for best-corrected visual acuity (BCVA), central retinal thickness (CRT) measured with OCT and occurrence of adverse events. Retinal pigment epithelium atrophy (RPEA) was assessed at baseline and at 12 months. Results: Mean BCVA improved by 4.7 letters (95% CI: 2.1-7.3, p < 0.001) and CRT decreased by 97.2 µm (95% CI: 54.4-140.1, p < 0.001) at 12 months compared to baseline. Median RPEA area increased by 0.48 mm2 (range = -0.1 to 19.9, p < 0.001). There was 1 arterial thromboembolic event and 2 cases of submacular haemorrhage. Conclusion: In this cohort of treatment-resistant nAMD patients, intravitreal aflibercept was effective in improving vision and reducing exudation. Early visual and anatomic outcomes may predict longer-term response to treatment, but further assessment is required.

Fuel cell is undoubtedly widespread energy conversion technology, which can convert fuel (biogas) energy into electricity. Solid oxide fuel cell (SOFC) is one of the best choices among the fuel cell’s family due to high efficiency and fuel flexibility. In this study, zinc-based nanostructured [Formula: see text] electrode materials were successfully developed by solid state reaction. The proposed materials have been characterized by XRD and SEM. The electrical conductivities have been examined by four-probe DC method in the temperature range of 300–600[Formula: see text]C, the maximum values were recorded and found to be 12.019 and 5.106 S/cm at natural gas and air atmosphere, respectively. The electrochemical performance has been measured employing NK-SDC electrolyte material and their current density versus voltage and current density versus power density (I-V and I-P characteristics) have been drawn. The maximum power density was found to be 170 mW/cm2 using natural gas as a bio-fuel over a temperature of 600[Formula: see text]C.

A number of complications are reported with the use of intrauterine contraceptive devices. These may pursue asymptomatic course or present as an acute abdomen after migration into peritoneal cavity. The authors here are reporting an abdominal wall swelling caused by transuterine migration of a copper intrauterine contraceptive device in a 28-year-old female. An open approach was used, and impacted foreign body was retrieved.