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Abstract It has been well documented that the usage of a textured cover layer reduces reflection from the air‐solar cell interface, which ultimately enhances the power conversion efficiency (PCE) of a solar cell. The most commonly used patterns, such as pyramids, micropillars, nanowires (NW), and nanoholes have been widely studied and optimized. Besides using such NWs to enhance light absorption, this work also additionally considers the concept of mimicking the antireflection coating of single or multiple layers in minimizing the reflectance and thus enhancing the total absorptance further. It is shown here that at least one order of magnitude shorter multilayer NW pattern of 268 nm total height can outperform a standard NW of 4270 nm height, which needs less material and can also be fabricated at a reduced cost. Furthermore, the proposed design with reduced height has a significantly lower surface‐to‐volume ratio, which also reduces surface recombination loss than the other textured surface patterns. The results presented in this work have been comprehensively analyzed by initially optimizing optical absorption and then completing the electrical simulations. The optimized design in conjunction with a back reflector offers an efficiency as high as 16.434%.

Fungal keratitis is one of the major causes of microbial keratitis that may lead to corneal blindness. Many problems related to diagnosis and therapy are encountered in fungal keratitis, including difficulty in obtaining laboratory diagnoses and the availability and efficacy of antifungal medications. Intensive and prolonged use of antifungal topical preparations may not be enough. The use of antifungal medications is considered the main treatment for fungal keratitis. It is recommended to start antifungal therapy after confirmation of the clinical diagnosis with a smear or positive cultures. Topical application of antifungal medications is a mainstay for the treatment of fungal keratitis; however, systemic, intra-stromal, or intra-cameral routes may be used. Therapeutic keratoplasty is the main surgical procedure approved for the management of fungal keratitis with good success rate. Intrastromal corneal injection of antifungal medications may result in steady-state drug levels within the corneal tissue and prevent intervals of decreased antifungal drug concentration below its therapeutic level. In cases of severe fungal keratitis with deep stromal infiltration not responding to treatment, intracameral injection of antifungal agents may be effective. Collagen cross-linking has been proposed to be beneficial for cases of fungal keratitis as a stand-alone therapy or as an adjunct to antifungal medications. Although collagen cross-linking has been extensively studied in the past few years, its protocol still needs many modifications to optimize UV fluence levels, irradiation time, and concentration of riboflavin to achieve 100% microbial killing. [ABSTRACT FROM AUTHOR]

Proportional-Integral-Derivative control is the most used kind of control which provides the simplest and most effective solution to different kinds of control engineering applications. But until now PID controller is poorly tuned in real life and online applications. While most of PID tuning is done manually. Switched reluctance motor (SRM) has highly nonlinear characteristics since the developed/produced torque of the motor has a nonlinear function on both phase current and rotor position. These nonlinearities of the SRM drives make the conventional PID (proportional + integral + Derivative) controller a poor choice for application where high dynamic performance is desired under all motor operating conditions. research paper comes up with two artificial and hybrid techniques involving Genetic Algorithm (GA) and Ant Colony Optimization (ACO). Those techniques where used to tune the PID parameters for the switched reluctance motor (SRM) and its performance were compared with the conventional method of “Ziegler Nichols. The results obtained reflects that, the use of those algorithms based controller improves the performance of the whole process in terms of a fast set point tracking and regulatory changes and also provides an optimum stability for the system itself with a minimum overshoot on the output signal.

Historical texts are one of the main pillars for understanding current civilization and are used to reference different aspects. Hadiths are an example of one of the historical texts that should be securely preserved. Due to the expansion of the online resources, fabrications and alterations of fake Hadiths are easily feasible. Therefore, it has become more challenging to authenticate the online available Hadith contents and much harder to keep these authenticated results secure and unmanipulated. In this research, we are using the capabilities of the distributed blockchain technology to securely archive the Hadith and its level of authenticity in a blockchain. We selected a permissioned blockchain customized model in which the main entities approving the level of authenticity of the Hadith are well-established and specialized institutions in the main Islamic countries that can apply their own Hadith validation model. The proposed solution guarantees its integrity using the crowd wisdom represented in the selected nodes in the blockchain, which uses voting algorithms to decide the insertion of any new Hadiths into the database. This technique secures data integrity at any given time. If any organization's credentials are compromised and used to update the data maliciously, 50% + 1 approval from the whole network nodes will be required. In case of any malicious or misguided information during the state of reaching consensus, the system will self-heal using practical Byzantine Fault Tolerance (pBFT). We evaluated the proposed framework's read/write performance and found it adequate for the operational requirements. [ABSTRACT FROM AUTHOR]

Background: Neonatal jaundice is one of the most common neonatal problems especially in preterm ones. Preterm babies are treated with different types of phototherapy. Preterm neonates have a weak antioxidant defense mechanism. Both the hyperbilirubinemia and phototherapy have an impact on this antioxidant defense system. Objective: In the current study we aimed to assess the effect of hyperbilirubinemia and phototherapy in the oxidant/antioxidant status of preterm newborns. Subjects and Methods: Thirty late preterm (≥35 weeks) neonates with non-hemolytic neonatal jaundice in the 3-9 days of life were involved in the preset study, and received phototherapy. 15 healthy neonates of the same gestational and postnatal age without jaundice were included as a control. We assessed the total oxidant status (TOS), total antioxidant capacity (TAC), and oxidative stress index (OSI). Results: TOS and OSI were significantly higher (P<0.01); TAC level was significantly lower (P<0. 01); in jaundiced preterm neonates than in control group. Following phototherapy there were significant increase in TOS and OSI (P<0. 01) and decrease in TAC (P<0.001). Conclusions: Both hyperbilirubinemia and phototherapy induce oxidative stress in preterm neonates. [ABSTRACT FROM AUTHOR]

The number of procedures for upgrading implantable devices for cardiac resynchronization therapy has increased considerably during the last decade. A major challenge that operators face in these circumstances is occlusion of the access vein. We have modified a pull-through method to overcome this obstacle. Six consecutive patients with occluded access veins and well-developed collateral networks underwent a procedure in which the occluded vein was recanalized by snaring the existing atrial lead via transfemoral access. Upgrading the device was successful in all patients; none had intraprocedural complications. Our experience shows that our modified pull-through technique may be a feasible alternative for upgrading cardiac resynchronization therapy in patients with venous occlusion. [ABSTRACT FROM AUTHOR]

Cuttings of Bougainvillea x buttiana "Mrs Butt" were cultured in peat moss [after treating with 1000 ppm indolebutric acid (IBA) or without] or hydroponic units contained: water, quarter Hoagland strength, half Hoagland strength, full Hoagland strength, 2.5 ppm, 5 ppm or 20 ppm IBA solutions. Results showed that treating cuttings with IBA at 1000 ppm before culturing was more effective than culturing without treating. Among the different hydroponic solution treatments, IBA solution at medium (5 ppm) or high concentration (10 ppm) had the best results, since they produced the highest values of rooting percentage, number of roots/cutting, number of shoots/cutting, shoot length, number of leaves/shoot and survival percentage. Also, using of 10 ppm IBA solution resulted in initiating the first root more rapidly than all other treatments. [ABSTRACT FROM AUTHOR]

Aims: Initial studies of catheter-based renal arterial sympathetic denervation to lower blood pressure in resistant hypertensive patients renewed interest in the sympathetic nervous system's role in the pathogenesis of hypertension. However, the SYMPLICITY HTN-3 study failed to meet its prespecified blood pressure lowering efficacy endpoint. To date, only a limited number of studies have described the microanatomy of renal nerves, of which, only two involve humans.Methods and Results: Renal arteries were harvested from 15 cadavers from the Klinikum Osnabruck and Schuchtermann Klinik, Bad Rothenfelde. Each artery was divided longitudinally in equal thirds (proximal, middle, and distal), with each section then divided into equal superior, inferior, anterior, and posterior quadrants, which were then stained. Segments containing no renal nerves were given a score value = 0, 1-2 nerves with diameter <300 µm a score = 1; 3-4 nerves or nerve diameter 300-599 µm a score = 2, and >4 nerves or nerve diameter ≥600 µm a score = 3. A total of 22 renal arteries (9 right-sided, 13 left-sided) were suitable for examination. Overall, 691 sections of 5 mm thickness were prepared. Right renal arteries had significantly higher mean innervation grade (1.56 ± 0.85) compared to left renal arteries (1.09 ± 0.87) (P < 0.001). Medial (1.30 ± 0.59) and distal (1.39 ± 0.62) innervation was higher than the proximal (1.17 ± 0.55) segments (p < 0.001). When divided in quadrants, the anterior (1.52 ± 0.96) and superior (1.71 ± 0.89) segments were more innervated compared to posterior (0.96 ± 0.72) and inferior (0.90 ± 0.68) segments (P < 0.001).Conclusions: That the right renal artery has significantly higher innervation scores than the left. The anterior and superior quadrants of the renal arteries scored higher in innervation than the posterior and inferior quadrants did. The distal third of the renal arteries are more innervated than the more proximal segments. These findings warrant further evaluation of the spatial innervation patterns of the renal artery in order to understand how it may enhance catheter-based renal arterial denervation procedural strategy and outcomes.Condensed Abstract: The SYMPLICITY HTN-3 study dealt a blow to the idea of the catheter-based renal arterial sympathetic denervation. We investigated the location and patterns of periarterial renal nerves in cadaveric human renal arteries. To quantify the density of the renal nerves we created a novel innervation score. On average the right renal arteries were significantly more densely innervated than the left renal arteries, the anterior and superior segments were significantly more innervated compared to the posterior and inferior segments, absolute innervation scores in the proximal third of the left or right renal arteries were always lower when compared to distal segments. These findings may enhance catheter-based renal arterial denervation procedural strategy and outcomes. [ABSTRACT FROM AUTHOR]

Transient apical ballooning syndrome or Takotsubo cardiomyopathy (TC) is a novel acute cardiac syndrome, characterized by regional systolic dysfunction involving the apex and mid-ventricular segments, with hyperkinesis of the basal segments. Mid-ventricular ballooning cardiomyopathy (MVBC) is a recently recognized variant of TC. Both disorders share the same precipitating factors, clinical features and course; however, unlike TC, MVBC is characterized by ballooning and akinesis of the mid-ventricular segments with hypercontractility of the basal and apical segments. While the precise pathogenetic mechanism of this disorder remains elusive, microvascular dysfunction from excessive catecholamine release has been implicated. We report findings on regional contractile dysfunction (strain imaging), myocardial blood flow (semi-quantitative), and perfusion kinetics using myocardial contrast echocardiography in a series of three illustrative cases of TC. [ABSTRACT FROM PUBLISHER]

Two new implantable cardioverter defibrillator systems developed for compatibility with magnetic resonance imaging demonstrate safety and efficacy in the Evera MRI and ProMRI trials, with no significant changes in ventricular pacing threshold < 5.0 V or ventricular sensing. In addition, there were no serious device-related events in both studies. [ABSTRACT FROM AUTHOR]

Background: Transesophageal echocardiography (TEE) has not been compared to transthoracic echocardiography (TTE) for assessment of left ventricular diastolic function (LVDF). Left ventricular diastolic dysfunction is common in systemic lupus erythematosus (SLE), a disease model of premature myocardial disease., Methods: 66 patients with SLE (mean age 36±12 years, 91% women) and 26 age-and-sex matched healthy volunteers (mean age 34±11 years, 85% women) underwent TEE immediately followed by TTE. From basal four-chamber views, mitral inflow E and A velocities, E/A ratio, E deceleration time, isovolumic relaxation time, septal and lateral mitral E' and A' velocities, septal E'/A' ratio, mitral E to septal and lateral E' ratios, and pulmonary veins systolic to diastolic peak velocities ratio were measured. Measurements were averaged over 3 cardiac cycles and performed by 2 independent observers., Results: LVDF parameters were worse in patients than in controls by TEE and TTE (all p≤0.03). Most LVDF parameters were similar within each group by TEE and TTE (all p≥0.17). By both techniques, mitral E and A, mitral and septal E/A ratios, septal and lateral E', septal and lateral E/E' ratios, and average E/E' ratio were highly correlated (r=0.64-0.96, all p≤0.003); E deceleration time, isovolumic relaxation time, and septal A' velocities were moderately correlated (r=0.43-0.54, all p≤0.03); and pulmonary veins systolic to diastolic ratio showed the lowest correlation (r=0.27, p=0.04)., Conclusion: By TEE and TTE, LVDF parameters were worse in SLE patients than in controls; and in both groups, LVDF parameters assessed by TEE and TTE were similar and significantly correlated., Competing Interests: Conflicts of Interest None.

Background: To report our experience and evaluate the results of a hybrid procedure comprising of surgical thrombectomy and adjuvant high pressure balloon angioplasty for management of thrombosed arteriovenous grafts (AVGs) with underlying venous anastomotic stenosis., Methods: Between January 2015 and June 2017, 148 patients with first-time thrombosis of AVGs were considered for treatment with surgical thrombectomy followed by high pressure balloon angioplasty of the underlying venous anastomotic lesions. Monitoring and surveillance was subsequently performed using clinical and hemodialysis criteria to detect a failing/failed access. Primary, assisted primary, and secondary patency rates were calculated using Kaplan-Meier analysis., Results: This hybrid procedure was technically successful in 135 cases (91.2%) and clinically successful in 131 cases (88.5%). The postintervention primary patency rate of the target lesions was 68.2%, 52.4%, and 44.2% at 3, 6, and 12 months, respectively. Endovascular re-interventions increased significantly the postintervention assisted primary patency to 79.1%, 71.9%, and 66.8% (P=0.0004), and the postintervention secondary patency to 86.5%, 82.2%, and 78.6% (P<0.0001) at the same time points, respectively., Conclusions: Hybrid salvage of thrombosed AVGs using high pressure balloon angioplasty of the venous anastomotic stenosis following surgical thrombectomy by Fogarty catheter is a highly successful and safe procedure, with acceptable short-term primary patency. The need for repeated interventions demonstrates the necessity of continuous graft monitoring and surveillance to improve both assisted primary, and secondary patency rates.

Implantable cardiac devices have become the mainstay of the treatment of patients with heart disease. However, data regarding their reliability and, inferentially, safety have been called into question. We reviewed annual reports submitted to the Food and Drug Administration Office of Device Evaluation by device manufacturers from 2003 to 2007. The annual number of implantable cardiac defibrillators (ICDs) and cardiac resynchronization therapy defibrillator (CRT-D) implants, explants, and returned devices were tabulated along with the cumulative (Cum) number of implants for each device. We derived an annual explantation rate (AER) defined as the ratio of the annual number of explants less the number of normal battery depletions/Cum (×1000). From 2003 to 2007, 256,392 CRT-D and 459,300 ICD devices were implanted in the United States. The overall mean (±SD) AERs for ICD and CRT-D devices were, respectively, 49.5 (15.6) per 1000 ICD devices and 82.6 (35.5) per 1000 CRT-D devices. The AER for each device type significantly decreased over the study period (P for trend <0.001) although the AER for CRT-D devices was 38% higher than that for ICD devices (P < 0.001). On average, 20.3% of CRT-D devices and 22.6% of ICD devices were returned to the manufacturer for analysis after explantation. The rates of explanted CRT-D and ICD devices decreased from 2003 to 2007. Notwithstanding this favorable trend, the AER for CRT-D devices was higher than that for ICD devices. Improved methods for tracking individual device histories are needed for more precise estimates of the risk of device explantation for suspected malfunction. The proportion of devices returned to the manufacturer is suboptimal and needs to be improved to better understand the mechanisms of device malfunction.

Background: Left-sided native valve infective endocarditis (LNVIE) can result in mitral (MP) and aortic (AP) valve perforation, the prognostic significance of which remains poorly defined., Hypothesis: Valvular perforation is associated with worse outcomes., Methods: Retrospective review of patients with LNVIE during 1998-2005 was performed to examine characteristics and outcome predictors of LNVIE complicated by valve perforation. Patients were stratified as: group A: MP or AP detected by transesophageal echocardiography (TEE) or surgery; group B: no TEE evidence of MP or AP., Results: A total of 123 patients were included (group A = 47, group B = 76). In group A, 35 patients (74.5%) had MP alone, 11 (23.4%) had AP alone, and 1 patient had both. Severe valvular insufficiency was encountered more in group A (85.1% versus 59.2%, p = 0.003), so was hemodialysis (40.4% versus 17.1%, p = 0.004) and indications for valvular surgery (93.6% versus 77.6%, p = 0.02). Group A had a higher rate of in-hospital death (31.9% versus 15.8%, p = 0.04). Among patients who had an indication for valvular surgery, the in-hospital mortality rate for those who underwent valvular surgery was 16.7% in group A, and 7.9% in group B (p = 0.4), compared to those who did not undergo surgery (71.4% versus 33.3%, p = 0.04). Amongst survivors, hospital stay was on average 9.2 d longer in group A (38.9 versus 29.7 d, p = 0.05). Univariate analysis revealed association between lower survival and valvular perforation (odds ratio [OR]: 0.4, 95% confidence interval [CI]: 0.17-0.95), that was lost after adjusting for hemodialysis., Conclusions: Valve perforation complicating LNVIE is associated with hemodialysis, severe valvular insufficiency, and significant morbidity and mortality. Compared to conservative management, early surgical intervention is associated with improved survival., (Copyright 2009 Wiley Periodicals, Inc.)