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Various engineering applications commonly involve the flow of nanofluids over a porous 45° inclined square cylinder. Therefore, the current study is to assess the impact of the Darcy parameter (Da), nanoparticle volume fraction (ϕ), and Reynolds number (Re) on the momentum transport characteristics over the 45° inclined porous square cylinder. The governing equations were solved numerically using the Darcy–Brinkman–Forchheimer model for different values of Da (10−6≤Da≤10−2), nanoparticle volume fraction ϕ (0.01≤ϕ≤0.05), and Reynolds number Re (1≤Re≤40). The results for each parameter were visualized using streamline plots, velocity profiles within the porous cylinder, and vorticity contours. Complex flow behaviors were observed between Da = 10−3–10−2, flow separation detached and disappeared at the cylinder's downstream side at critical Darcy number. Drag and pressure coefficents are used to represent the global and local parameter of the flow fields. The pressure coefficient on the surface of the cylinder showed an inverse relationship with the nanoparticles volume fraction and Darcy number. The strength of the drag coefficient decreased with the addition of nanoparticles to the base fluid, with a decreasing trend observed for Da = 10−4–10−2 and no change observed for Da = 10−6–10−4. At last, the comparative analysis has been conducted between a porous square cylinder at 0° inclined and another 45° inclined. [ABSTRACT FROM AUTHOR]

This study investigated the momentum and thermal characteristics of a blunt‐headed cylinder immersed in a stream of generalized Newtonian fluids (i.e., power‐law fluids) under various planar confinements. The flow and heat transfer characteristics were obtained by solving the constitutive equations with a finite‐element‐based solver for varying ranges of governing parameters. Reynolds number (Re = 1–40), Prandtl number (Pr = 5–100), power‐law index (n = 0.3–1.8), and blockage ratios (β = 2–40) were considered as the governing parameters for the study. Streamlines, drag coefficients, isotherm contours, and average Nusselt numbers were obtained as output parameters of the study. The local distribution of the pressure coefficient and Nusselt number are also presented to gain deep insight into the vicinity of the blunt‐headed cylinder. Shear‐thickening and shear‐thinning fluids exhibited an inverse trend for flow separation under planar confinements. The average Nusselt number exhibits a positive correlation with the Reynolds and Prandtl numbers while showing negative dependence on the power‐law index and blockage ratio. Overall, momentum and heat transfer show complex relationships with the governing parameters. The functional relationships are shown as correlations for flow‐separation Reynolds number, total drag force, and average Nusselt number on relevant dimensionless parameters for general applications. [ABSTRACT FROM AUTHOR]

Group IV Ge1-xSnx alloy in bulk form and heterostructures using quantum wells (QWs) GeSn/SiGeSn pairs show promise for laser sources in recent years. In this paper, we present the design of transistor laser (TL) structure with a SiGeSn emitter, GeSn QW embedded in the SiGeSn base, and a GeSn collector grown on the top of 200 nm thick strain-relaxed GeSn buffer, compatible with current CMOS technology. The GeSn layer is assumed to have composition of x > 0.08 to achieve the direct band-gap nature. The lasing is examined in terms of minimum base threshold current and optimum lasing action obtained by using Ge 0.87 Sn 0.13 / Si 0.05 Ge 0.82 Sn 0.13 MQW TL structure. The performance of proposed structure is compared with the theoretical values of already reported GeSn TL and some of the experimental values of InGaAs TL. The proposed design reduces the lasing threshold base current to some extent (~ 1.133 mA) and enhances the modulation bandwidth upto ~ 75.9 GHz. [ABSTRACT FROM AUTHOR]

Ternary alloy InGaN made of III-V nitrides has attracted significant attention from many researchers in recent years due to its tunable energy band gap from far infra-red (0.7 eV) to deep ultra-violet (3.4 eV) parts of the electromagnetic spectrum. This material offers the band lineup, which is one of the most important parameters ensuring the better carrier confinement along the quantum wells (QWs). In this work, we design a strained multiple quantum well (MQW)-based tunnel-injection transistor laser (TI-TL) using InGaN (emitter)/GaN (base)/InGaN (collector) grown on a GaN virtual substrate, followed by an investigation of the optimized optical performance of the designed device with the use of strained QWs. The estimated values of modulation bandwidth are compared with already existing theoretical and experimental values of InGaAs-GaAs TL. Higher optical modulation bandwidth ∼66.06 GHz and lower base threshold current ∼1.67 mA, using strained InxGa1−xN QWs, are obtained for the proposed structure, which makes it a potential candidate for high-speed optical devices employed in high bit-rate optical communication networks. [ABSTRACT FROM AUTHOR]

In this present work, forced convection heat transfer from a heated blunt-headed cylinder in power-law fluids has been investigated numerically over the range of parameters, namely, Reynolds number (Re): 1–40, Prandtl number (Pr): 10–100 and power-law index (n): 0.3–1.8. The results are expressed in terms of local parameters, like streamline, isotherm, pressure coefficient, and local Nusselt number and global parameters, like wake length, drag coefficient, and average Nusselt number. The length of the recirculation zone on the rear side of the cylinder increases with the increasing value of Re and n. The effect of the total drag coefficient acting on the cylinder is seen to be higher at the low value of Re and its effect significant in shear-thinning fluids (n < 1). On the heat transfer aspect, the rate of heat transfer in fluids is increased by increasing the value of Re and Pr. The effect of heat transfer is enhanced in shear-thinning fluids up to ∼ 40% and it impedes it's to ∼20% shear-thickening fluids. In the end, the numerical results of the total drag coefficient and average Nusselt number (in terms of JH−factor) have been correlated by simple expression to estimate the intermediate value for the new application. [ABSTRACT FROM AUTHOR]

Highlights • Study and analysis is focused on use of Group III-V material. • Discussion on structures, performances, and results related to some important works. • Comparison of some important characteristics of TI-MQW-TL by varying SCH width. • Proposed structure shows better performance than previously reported works. Abstract Transistor Laser has already established as a promising candidate for high speed optical interconnects and optical telecommunication networks. The present work is focused on the performance of multiple quantum wells (MQW) based transistor laser by incorporating tunnel injection phenomenon and it's performance by varying the width of the separate confinement heterostructure layer. The virtual state (VS) is assumed as a path for the movement of injected charge carriers from bulk to nanostructures. We have estimated the various characteristics such as base threshold current, light power output, and optical modulation response by considering various physical parameters such as diffusion time, gain compression factor, optical confinement factor, photon lifetime, tunneling time and diffusion length, as a function of separate confinement hetero-structure (SCH) layer thickness. It is found that with increasing thickness of the SCH layer, base threshold current reduces, the light output power increases, but the optical modulation response remains almost constant, which ensures the potentiality of the proposed structure for high speed opto-electronic transmitter with low power consumption. [ABSTRACT FROM AUTHOR]

This case report highlights the management of nonfunctional pituitary macroadenoma with volumetric-modulated arc radiotherapy, compared to three-dimensional conformal radiotherapy. [ABSTRACT FROM AUTHOR]

Contemporary computing employs cache hierarchy to fill the speed gap between processors and main memories. In order to optimise system performance, Last Level Caches (LLC) are shared among all the cores. Cache sharing has made them an attractive surface for cross-core timing channel attacks. In these attacks, an attacker running on another core can exploit the access timing of the victim process to infiltrate the secret information. One such attack is called a cross-core Covert Channel Attack (CCA). Timely detection and then prevention of cross-core CCA is critical for maintaining the integrity and security of users, especially in a shared computing environment. In this work, we have proposed an efficient cross-core CCA mitigation technique. We propose a way-wise cache partitioning on targeted sets, only for the processes suspected to be attackers. In this way, the performance impact on the entire LLC is minimised, and benign applications can utilise the LLC to its full capacity. We have used a cycle-accurate simulator (gem5) to analyse the performance of the proposed method and its security effectiveness. It has been successful in abolishing the cross-core covert timing channel attack with no significant performance impact on benign applications. It causes 23% less cache misses in comparison to existing partitioning based solutions while requiring ≈ 0. 26 % storage overhead. [ABSTRACT FROM AUTHOR]

Objective: Unusual clinical course Background: Systemic lupus erythematosus (SLE) is a multisystem autoimmune disorder of unknown etiology which can present at any age with symptoms of mucocutaneous, musculoskeletal, renal, central nervous system, and nonspecific clinical pictures making the disease a "master of mimicry". Case Report: A 53-year-old female, who was recently diagnosed with SLE, presented with right-sided sharp and electric shocklike facial pain starting at the side of her right nostril and traveling down the naso-labial fold and then back to the angle of the jaw, mostly in the region of V2-V3 distribution with no radiation beyond trigeminal distribution. Her pain had been going for the last 2 years and was regarded as "pretrigeminal neuralgia"; however, it progressed in frequency over the last 2 weeks, with no clear identifying triggering factors. Her laboratory test results showed positive anti-nuclear antibodies (ANA) with raised titer, anti-double-stranded DNA, anti-ribonucleoprotein, anti-Sjögren's syndrome-related antigen A, anti-Sjögren's syndrome-related antigen B, and anti-smooth muscle antibodies. Other possibilities of migraine, postherpetic neuralgia, Bell's palsy, and brain tumor were ruled out. A diagnosis of SLE with trigeminal neuralgia (TN) was made and carbamazepine 100 mg 2 times a day was prescribed. Conclusions: TN is seldom mentioned as a neurological manifestation of SLE; hence, we recommend further studies to investigate the SLE-mediated injury to trigeminal fibers to make a timely diagnosis of TN and to prevent progressive autoimmune process-related vasculitic and demyelinating changes. [ABSTRACT FROM AUTHOR]

Paliperidone, an active metabolite of risperidone, is a new atypical antipsychotic agent. Syndrome of inappropriate antidiuretic hormone (SIADH), neuroleptic malignant syndrome (NMS), and rhabdomyolysis are the uncommon side effects of psychotropic drugs. We report a case of 35-year-old male with schizoaffective disorder who was admitted for acute-on-chronic exacerbation of his psychotic disorder for which intramuscular paliperidone 234 mg injection was given. Two days later, the patient developed hyponatremic seizures secondary to SIADH which was treated with hypertonic saline. On the third day, he developed high grade fever and severe muscle rigidity with raised creatine phosphokinase (CPK) and liver enzymes levels. He was treated with dantrolene 100 mg, bromocriptine 2.5 mg, and lorazepam 2 mg. Our patient required management of the three rare conditions following treatment with paliperidone. This case highlights the need for health care providers to be aware of the rare, potentially life threatening but preventable hyponatremia, NMS, and rhabdomyolysis as a possible adverse effect of paliperidone. [ABSTRACT FROM AUTHOR]

Metabolic syndrome is defined by a constellation of interconnected physiological, biochemical, clinical, and metabolic factors that directly increases the risk of cardiovascular disease, type 2 diabetes mellitus, and all cause mortality. Insulin resistance, visceral adiposity, atherogenic dyslipidemia, endothelial dysfunction, genetic susceptibility, elevated blood pressure, hypercoagulable state, and chronic stress are the several factors which constitute the syndrome. Chronic inflammation is known to be associated with visceral obesity and insulin resistance which is characterized by production of abnormal adipocytokines such as tumor necrosis factor α, interleukin-1 (IL-1), IL-6, leptin, and adiponectin. The interaction between components of the clinical phenotype of the syndrome with its biological phenotype (insulin resistance, dyslipidemia, etc.) contributes to the development of a proinflammatory state and further a chronic, subclinical vascular inflammation which modulates and results in atherosclerotic processes. Lifestyle modification remains the initial intervention of choice for such population. Modern lifestyle modification therapy combines specific recommendations on diet and exercise with behavioural strategies. Pharmacological treatment should be considered for those whose risk factors are not adequately reduced with lifestyle changes. This review provides summary of literature related to the syndrome's definition, epidemiology, underlying pathogenesis, and treatment approaches of each of the risk factors comprising metabolic syndrome. [ABSTRACT FROM AUTHOR]

Principal factors leading to the efficient alternating current (AC) field‐induced heating of magnetic fluids are determined based on the results of magnetic and calorimetric measurements on NaFeO2 nanoparticles and their fluids. Features of the magnetic behavior are singled out, and characteristic magnetic parameters, such as the Curie and blocking temperatures, are determined for the NaFeO2 nanoparticles. The dependence of the fluid caloric properties on the AC magnetic field amplitude and nanoparticle concentration is analyzed. It is shown that the heating efficiency of the weakly coercive NaFeO2 nanoparticles displays an amplitude threshold character, and the heating rate is critically dependent on the AC magnetic field amplitude. [ABSTRACT FROM AUTHOR]

Ternary alloy Si 1-x-y Ge x Sn y or Ge x Sn 1-x made up of group IV elements has been receiving attention from researchers in recent years due to its direct band gap nature. In this work, we investigate the performance of solar cells made with this alloy. We have proposed a n+ Si 1-x-y Ge x Sn y (emitter)/p- Si 1-x Ge x (absorber)/p- Si 1-x-y Ge x Sn y (base) /p+ Si 1-x-y Ge x Sn y (back surface field layer: BSF) based solar cell grown on Si 1-x-y Ge x Sn y substrate. The calculated values are compared with the values for existing Si 1-x Ge x solar cells and comparatively improved performances are obtained for the proposed structure. The effects of different absorber layer thickness, doping concentrations of the absorber and BSF layers, Ge concentration in Si 1-x Ge x and Sn concentration in Si 1-x-y Ge x Sn y are also studied for the proposed structure. Conversion efficiency is as high as 19.9 % for substrate thickness as low as 10 μm has been obtained for the proposed structure. The low value of substrate thickness and high efficiency make the proposed structure attractive as a low-cost device for applications in spacecraft and satellites. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid perovskite solar cells (PSCs) have made significant progress in achieving record-high efficiency in the past few years. However, the basic problem for commercialization is the interplay between high efficiency, scalable manufacturing, and chemical stability of the perovskite solar cell. Most efficient PSCs rely on Spiro-OMeTAD-based organic hole transporting layer (OHTL) which suffers from chemical instability, expensive material cost, and low durability. Herein, we demonstrate novel Li/Na-ferrite (LiFeO2/NaFeO2)-based inorganic hole transporting layers (IHTLs) as a potential replacement for Spiro-OMeTAD OHTL, leading to optimized PSCs with high efficiency and long-term chemical stability. The solar cell has been fabricated using the spin coating technique. The performance parameter of the device has been probed by investigating structural, optical, electrical, and photoconversion efficiency as well as simulation of the solar cell. PSCs using Li and Na-ferrite as IHTLs exhibited power conversion efficiency (PCE) ~ 17.5% and ~ 17.1%, respectively, which surpassed the overall performance of Spiro-OMeTAD-based PSC that exhibited PCE ~ 14.4%. The experimental and theoretical studies confirm the stabilized interfacial effect of Li/Na-ferrite IHTLs that strongly controls the crystallization of the perovskite films, charge carrier transport, and trap density, which leads to reduce non-radiative charge recombination losses and improved device stability for long-term operation. Our work highlights the significance of ferrite-based IHTLs as promising candidates for future efficient and stable perovskite solar cells. [ABSTRACT FROM AUTHOR]

Perovskite solar cells attract significant interest due to their high-power conversion efficiencies. The replacement of charge-transporting layers using inorganic materials is an effective approach for improving stability and performance, as these materials are low-cost, highly durable, and environmentally friendly. This work focuses on the inorganic hole and electron transport layers (HTL and ETL), strontium ferrite (SrFe2O4), and zinc oxide (ZnO), respectively, to enhance the efficiency of perovskite solar cells. Favorable band alignment and high charge-collection capability make these materials promising. Experimental and computational studies revealed that the power conversion efficiency of the fabricated device is 7.80% and 8.83%, respectively. Investigating electronic properties and interface charge transfer through density functional theory calculations further corroborated that SrFe2O4 is a good HTL candidate. Our numerical device modeling reveals the importance of optimizing the thickness (100 nm and 300 nm) of the HTL and perovskite layers and defect density (1016 cm−3) of the absorber to achieve better solar cell performance. [ABSTRACT FROM AUTHOR]

Due to the gigantic rise in the use of high data rate-based applications and the ongoing transformation of Indian cities into smart cities, there is a need for a high-speed communication framework to handle the enormous data traffic. The radio frequency (RF) and microwave links seem to be incapable of offering sufficient bandwidth required by the data-hungry applications and consequently, the need for a more effective solution for tackling the issue of scarcity of bandwidth resources has become the necessity of current network infrastructure in India. In this study, a hybrid optical fiber-free space optical (OF-FSO) system for offering high-speed data services has been proposed to assist the implementation of smart city infrastructure in India. This study aims to inspect the system performance of the proposed model under the climatic conditions of mountainous, desert, flatland, and seaside regions of India. The proposed hybrid OF-FSO system comprises a fixed single-mode fiber (SMF) of 20 km and an FSO link (having a varied transmission range between 0–2 km). The proposed hybrid model can support an FSO link of 1.72 km for a fixed SMF of 20 km, corresponding to a bit error rate of the order of 1 0 − 4 for atmospheric conditions of the seaside location of Chennai and the range of FSO link varies from 1.32 km to 1.57 km for other locations of India, for the same length of SMF and bit error rate. Furthermore, the proposed hybrid OF-FSO has demonstrated a reduction of 30.8% in Capital Expenditure (CAPEX) cost in contrast to the conventional passive optical network (PON) system. • The proposed model has delivered promising results for supporting smart city applications. • The model has been tested for the climatic conditions of diverse geographical locations in India. • The proposed model can transmit data for an SMF of 20 km and an FSO link of 1 km for all locations. • For a target bit error rate of 10−4, the maximum possible FSO link range varies from 1.32 to 1.72 km. • The proposed model has reduced the CAPEX by 30.8% in contrast to the conventional PON system. [ABSTRACT FROM AUTHOR]

This case report highlights the management of single metastasis in the liver with stereotactic body radiotherapy in a previously treated case of carcinoma breast. [ABSTRACT FROM AUTHOR]

Homocysteine (tHcy) has been hardly studied among patients with head injury. This study was to evaluate whether there is any independent impact of tHcy levels on neurological outcome following head injury in a multivariate model. Patients admitted within 24 h of injury were included in the study, along with 20 age- and gender-matched controls. Plasma levels of tHcy were measured at admission using direct immunoassay. All the variables were analyzed with respect to tHcy levels and outcome according to Glasgow Outcome Score (GOS) at 3 months. Univariate and multivariate analyses were performed using SPSS 21. There were a total of 72 patients in the study. tHcy levels were significantly higher after head injury (mean 24.03[SD ± 16.0] μmol/L), compared to matched controls (mean 16.62 [SD ± 10.4] μmol/L) (p = 0.05). Patients with severe head injury, acute SDH, or diffuse higher radiological grades had greater levels of tHcy compared to others. There was a significant relationship between tHcy level and neurological outcome. tHcy levels were significantly higher in patients who had unfavorable GOS (mean 36.22[±25.3] μmol/L), compared to those with favorable GOS (mean 22.71[±14.3] μmol/L) (P = 0.03). In multivariate analysis, tHcy level (adj. odds ratio [OR] 1.17, P = 0.05) and Glasgow Coma Scale (adj. OR 5.17, P = 0.01) had significant association with neurological outcome at 3 months independent of age, dietary habit, radiological grading and of each other. tHcy level has significant independent impact on neurological outcome and may be useful as a prognostic marker following head injury. [ABSTRACT FROM AUTHOR]

Perovskite solar cells attract significant interest due to their high-power conversion efficiencies. The replacement of charge-transporting layers using inorganic materials is an effective approach for improving stability and performance, as these materials are low-cost, highly durable, and environmentally friendly. This work focuses on the inorganic hole and electron transport layers (HTL and ETL), strontium ferrite (SrFe2O4), and zinc oxide (ZnO), respectively, to enhance the efficiency of perovskite solar cells. Favorable band alignment and high charge-collection capability make these materials promising. Experimental and computational studies revealed that the power conversion efficiency of the fabricated device is 7.80% and 8.83%, respectively. Investigating electronic properties and interface charge transfer through density functional theory calculations further corroborated that SrFe2O4 is a good HTL candidate. Our numerical device modeling reveals the importance of optimizing the thickness (100 nm and 300 nm) of the HTL and perovskite layers and defect density (1016 cm−3) of the absorber to achieve better solar cell performance. [ABSTRACT FROM AUTHOR]