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The present article deals with the propagation of plane waves in a magneto-thermoelastic medium under the effects of variable thermal conductivity and variable mass diffusivity. It is observed that three coupled longitudinal plane waves and one transverse wave travel in the medium with distinct speeds. The formulae for amplitude ratios and energy ratios corresponding to various reflected waves have been presented, when a set of coupled waves strikes obliquely at the boundary surface of the assumed model. To illustrate the analytical developments, the numerical solution is performed for a particular material and the results in respect of phase velocities, amplitude ratios and energy ratios are presented graphically. It is observed that the results depend upon the angle of incidence, frequency and the thermoelastic properties of the half-space. It is verified that during reflection phenomena, the sum of energy ratios is equal to unity at each angle of incidence and there is no energy dissipation at the free plane boundary. Results of some earlier workers have been deduced from the present formulation. [ABSTRACT FROM AUTHOR]

In this article, a model of two dimensional problem of generalized thermoelasticity for a homogeneous isotropic nonlocal microstretch saturated porous medium with variable thermal conductivity is established. The enunciation is applied to generalized thermoelasticity theory based on Moore-Gibson-Thompson heat conduction model. The formulae for amplitude ratios and energy ratios corresponding to various reflected waves have been presented, when a set of coupled waves strikes obliquely at the boundary surface of the assumed model. The numerical values of modulus of reflection coefficients are presented graphically to depict the effects of microstretch parameter, porosity, variable thermal conductivity, and non local parameter. Expressions of energy ratios have also been obtained in explicit form and are shown graphically as functions of angle of incidence. It has been verified that during the reflection phenomenon, the sum of energy ratios is equal to unity at each angle of incidence. Results of some earlier workers have been deduced from the present formulation. [ABSTRACT FROM AUTHOR]

Current research is dedicated to study the thermo-mechanical interactions in a rotating magneto-thermoelastic diffusive medium with microconcentrations. The entire thermoelastic medium is rotating with a uniform angular velocity. The formulation is subjected to a mechanical load. Exact solution of the problem is procured by applying normal mode technique. Numerical computations for stresses, displacement components, temperature field, concentration, microconcentration and mass diffusion flux moment are performed for a suitable material and are depicted graphically. Some comparisons are made to show the effects of magnetic field, angular velocity, microconcentration parameter and time on the resulting quantities. Certain special cases of interest have been derived from the current report. [ABSTRACT FROM AUTHOR]

Non-bacterial thrombotic endocarditis (NBTE), formerly recognized as marantic endocarditis, represents a rare cardiovascular pathology intricately linked with hypercoagulable states, notably malignancy and autoimmune disorders. Characterized by the development of sterile vegetations comprised of fibrin and platelets on cardiac valves, NBTE poses a diagnostic challenge due to its resemblance to infective endocarditis. Therapeutic endeavours primarily revolve around addressing the underlying aetiology and instituting anticoagulant regimens to forestall embolic events, with surgical intervention seldom warranted. Non-bacterial thrombotic endocarditis frequently coexists with malignancies and autoimmune conditions, such as lupus and antiphospholipid antibody syndrome, and, more recently, has been associated with COVID-19. Its pathogenesis is underpinned by a complex interplay of endothelial dysfunction, hypercoagulability, hypoxia, and immune complex deposition. Clinical manifestations typically manifest as embolic phenomena, particularly cerebrovascular accidents, bearing substantial mortality rates. Diagnosis necessitates a high index of suspicion and meticulous exclusion of infective endocarditis, often facilitated by advanced cardiac imaging modalities. Anticoagulation, typically employing low molecular weight heparin or warfarin, constitutes the cornerstone of pharmacological intervention. Surgical recourse may be warranted in instances of refractory heart failure or recurrent embolic events. Given its multifaceted nature, the management of NBTE mandates a multidisciplinary approach, with prognosis contingent upon individual clinical intricacies. Future endeavours should prioritize further research to refine therapeutic strategies and enhance patient outcomes. [ABSTRACT FROM AUTHOR]

Smart polymers represent a class of advanced materials that undergo reversible changes in their physical or chemical form and are known as responsive polymers. These polymers show transitions when external stimuli, such as temperature and pH, come into play. Smart polymers are being increasingly applied in various fields, such as drug delivery to a targeted site and gene therapy. They also play a pivotal role in tissue engineering, environmental sensors, and the development of shape memory polymers. Despite their major challenges, they remain effective in overcoming significant barriers. It can be said that these polymers have the potential to revolutionize various fields. This review highlights the underlying types and applications of smart polymers, emphasizing their roles in the future. [ABSTRACT FROM AUTHOR]

Background: In recent years, drug abuse among the student population has increased to an alarming rate in India and that too among medical students. Substance abuse among medical students has important implications for their personal health, training, and clinical practice. Aims and Objectives: To plan effective interventions, it is essential to have information on the extent, type, and factors associated with substance abuse among medical students. Hence this study was undertaken to find the prevalence and pattern of substance abuse. Materials and Methods: A cross-sectional study was conducted among undergraduate medical college students of all professional years. Students were assessed for their pattern and prevalence of substance abuse with the help of a structured self-administered questionnaire entitled "Pattern of substance abuse among medical students" as a tool for data collection. The questionnaire had three domains viz. demographic characteristics, short Michigan alcohol screening test, and Fagerstrom test for assessment of level of nicotine dependence. The World Health Organization-Alcohol, Smoking, and Substance Involvement Screening Test Scale was also used to increase the validity of results. Results: Alcohol and Nicotine were the most commonly abused substances among medical students. The trend of abusing a substance increases as per increase in the ladder of professionalism. The majority of students initiated abuse because of peer pressure and mental stress during their academic life. The problem was more among hostellers. Most of the students continued the abuse because of the feeling of enjoyment and to increase their performance in the exams. Conclusion: Awareness creation and academic counseling camps along with stress interventions are recommended and needed to curb drug abuse among medical students. [ABSTRACT FROM AUTHOR]

This manuscript investigates the disruptions occurring in a two-dimensional homogeneous, isotropic, thermoelastic medium with diffusion, double porosity and microtemperatures under Lord and Shulman (LS) theory of generalized thermoelasticity. A mechanical load is applied at the outer free surface of the solid half-space. To procure the exact expressions for various field variables, normal mode analysis is utilized. Numerical computations are performed for a particular material and the acquired results are visualized through graphical representations with the aid of MATLAB software. Comparisons are carried out to elucidate the influences of diffusion parameter, time, double porosity and intensity of load on the resulting quantities. 2010 MSC: 74A15, 80A20. [ABSTRACT FROM AUTHOR]

The low responsivity of conventional Silicon photodiodes in ultraviolet and near-infrared regimes restricts their utility as broadband photodetectors (BBPDs). Despite ongoing investigations into various p-n heterostructures for Silicon-based BBPDs, challenges such as high dark current (I _dark ), low collection efficiency, low detectivity, and compatibility issues with large-scale Silicon-based devices persist. In this context, we have fabricated relatively unexplored n-Er _2 O _3 /p-Si heterojunction-based BBPDs. Polycrystalline Er _2 O _3 thin films (∼110 nm) were deposited on p-Si 〈100〉 substrates by radio frequency magnetron sputtering. Although this process induces a microstrain of approximately 0.022 and a dislocation density of about 0.00303/nm ^2 , the presence of optically active defects is minimal, indicated by a low Urbach energy (∼0.35 eV). X-ray photoelectron spectroscopy (XPS) analysis confirms staggered band alignment at the heterointerface, facilitating efficient charge carrier separation and transport. Consequently, the In/p-Si/n-Er _2 O _3 /In device demonstrated significant BBPD properties– low I _dark ∼0.15 μ A (at +5 V), photo-to-dark current ratio (PDCR) ∼6.5 (at +5 V, 700 nm) with a maximum photoresponsivity ∼22.3 A W ^−1 , and impressive detectivity (∼10 ^13 Jones) even in UV-C region where traditional silicon-based photodetectors respond feebly. The device also demonstrates transient photo-response across an ultrawide spectrum (254 nm–1200 nm) with a fast rise time/fall time ∼79 ms/∼86 ms (at −5 V for 600 nm illumination). This work establishes a straightforward and reliable method for proper material engineering, surface texturing, staggered heterojunction formation, and high-performance BBPD fabrication with prominent broad-spectrum responsivity, sizeable detectivity, and fast response. The integration of these BBPDs with Silicon opens possibilities for their use in electronic devices containing optical switches for communications and broadband image sensors, enhancing their utility in various applications.

Objectives Patients with systemic lupus erythematosus (SLE) have a high risk of cardiovascular disease that could potentially increase postoperative major adverse cardiac events (MACE). We determined the rate of MACE in patients with SLE undergoing noncardiac surgery using national claims‐based data. Methods This was a retrospective cohort study using Optum Clinformatics Data Mart from 2007 to 2020. We identified a cohort of patients with SLE who had undergone noncardiac surgeries using Current Procedural Terminology codes. We also identified two control cohorts without SLE, one with diabetes mellitus (DM) and one without DM. After matching cases and controls by age and sex, the odds of MACE were estimated using multivariable logistic regression models also including race and the Revised Cardiac Risk Index (RCRI) scores. We also examined use of preoperative cardiac testing. Results We identified 4750 patients with SLE, 496,381 DM controls, and 1,484,986 non‐DM controls. After matching, the odds ratio (OR) for MACE in patients with SLE versus non‐DM controls was 1.51 (95% confidence interval 1.09‐2.08), which decreased after adjustment for RCRI score (OR: 0.97, 95% confidence interval 0.7‐1.36). No significant differences were observed in the incidence of MACE between patients with SLE and DM controls (0.82 vs 1.04, P = 0.16). High‐risk patients with SLE (RCRI score of ≥3) were less likely to receive preoperative cardiac testing than non‐DM controls (42.7% vs 35.1%, P

Cancer survivors undergone treatment face an increased risk of developing atherosclerotic cardiovascular disease (CVD), yet the underlying mechanisms remain elusive. Recent studies have revealed that chemotherapy can drive senescent cancer cells to acquire a proliferative phenotype known as senescence-associated stemness (SAS). These SAS cells exhibit enhanced growth and resistance to cancer treatment, thereby contributing to disease progression. Endothelial cell (EC) senescence has been implicated in atherosclerosis and cancer, including among cancer survivors. Treatment modalities for cancer can induce EC senescence, leading to the development of SAS phenotype and subsequent atherosclerosis in cancer survivors. Consequently, targeting senescent ECs displaying the SAS phenotype hold promise as a therapeutic approach for managing atherosclerotic CVD in this population. This review aims to provide a mechanistic understanding of SAS induction in ECs and its contribution to atherosclerosis among cancer survivors. We delve into the mechanisms underlying EC senescence in response to disturbed flow and ionizing radiation, which play pivotal role in atherosclerosis and cancer. Key pathways, including p90RSK/TERF2IP, TGFβR1/SMAD, and BH4 signaling are explored as potential targets for cancer treatment. By comprehending the similarities and distinctions between different types of senescence and the associated pathways, we can pave the way for targeted interventions aim at enhancing the cardiovascular health of this vulnerable population. The insights gained from this review may facilitate the development of novel therapeutic strategies for managing atherosclerotic CVD in cancer survivors.

Objective: To compare the efficacy of oral dexamethasone and prednisolone in the treatment of newly diagnosed children aged 3–36 months of West syndrome. Methods: An open-labeled, randomized controlled clinical trial with parallel group assignment was conducted among children aged 3–36 months with newly diagnosed West syndrome. They were randomized to receive either oral dexamethasone (0.6 mg/kg/day QID) (n = 20) or oral prednisolone (4 mg/kg/day BD) (n = 20). Proportion of children who achieved spasm freedom at 2 weeks was the primary outcome. Secondary outcome measures were proportion of children who achieved electroclinical resolution, greater than 50% reduction in spasms frequency, time to cessation of spasms, and adverse effects at 2 weeks. Results: The efficacy of oral dexamethasone was comparable to oral prednisolone in terms of proportion of children who achieved spasms cessation (13 [65%] vs. 8 [40%]; P = 0.21), electroclinical remission (13 [65%] vs. 8 [40%] P = 0.21), greater than 50% reduction of spasms (3 [15%] vs. 7 [35%] P = 0.65), and time to cessation of spasms (5.31 [2.81] vs. 4.37 [1.41] P = 0.39). Adverse effect profile was also comparable with irritability (18 [90%] vs. 12 [60%] P = 0.06] being most common. Conclusion: There was no difference in electroclinical remission at 2 weeks between oral dexamethasone and prednisolone in children with infantile spasms in this small pilot trial. Further evaluation is suggested with an adequately powered study and long-term follow-up.

Typhoid, paratyphoid, leptospirosis, scrub typhus, and melioidosis are some of the common bacterial infections which are endemic in the region of South Asia. Typhoid and paratyphoid cause enteric fever which is a common cause of fever in the general population in this region. It is caused by Salmonella through contaminated food and water. Enteric fever is one of the most common causes of fever in travelers in this region. Leptospirosis is a zoonotic disease caused by Leptospira and occurs due to direct contact with animals like or through abraded skin after the monsoon in the endemic area. Fever and jaundice are the most common presentations. Scrub typhus is caused by mite Orientia tsutsugamushi and it has now emerged as one of the most common causes of pyrexia in this region. Melioidosis is an uncommon infection caused by the bacteria Burkholderia pseudomalle, which is endemic in some regions of South Asia and is usually seen in immunocompromised individuals. Melioidosis is often called great mimicker due to a variety of clinical manifestations which might confuse it with other diseases. All these infections can cause fever or other systemic complications involving various organs in transplant recipients, so they should be kept as part of differential diagnosis of pyrexia in transplant recipients. There are no recommendations to screen for these infections in transplant candidates or donors, however, transplant candidates or donors with fever should be investigated for these infections and transplant should be deferred until full recovery and for some time thereafter.

This paper presents a novel model for transformer windings to accurately represent the duality between electrical and magnetic circuits. The model can be used for the calculation of high-frequency transients in power systems and the design of high-frequency transformers, for example, those to be used in solid-state (utility-grade) transformers and power electronic converters. Existing circuit models do not consider the flux linkage in the winding thickness in a physical (dual) way. Duality is achieved by discretizing the winding thickness into thin sub-sections and distributing the proposed model building block across the winding. Analytical calculations are carried out to compare the accuracy of the proposed circuit for the computation of the terminal impedance, flux duality, and current distribution in the physical geometry of the winding. Further discretization is performed to extend the circuit to represent high-frequency phenomena: eddy currents and capacitive effects. The model can be easily implemented in any circuit simulation program using available circuit elements. The circuit parameters are computed with very simple expressions. The model is validated with finite element simulations. Differences of around 1% are obtained for relatively low model orders for high frequencies.

Background: Chronic intestinal pseudo-obstruction (CIPO) is an umbrella term for a range of different conditions characterized by repetitive episodes or continuous symptoms and signs of bowel obstruction, including radiographic evidence of dilated intestines and air-fluid levels, due to impaired propulsion in the absence of an anatomical occluding lesion. It is a diagnostic challenge and can mimic Hirschsprung's disease. Clinical Description: A 10-month-old boy presented with a history of recurrent episodes of constipation since the age of 6.5 months. The first two had resolved with symptomatic treatment. The third had been associated with bilious vomiting and required exploratory laparotomy. He was referred to us when there was no symptomatic improvement. The child underwent extensive workup that included a review of earlier investigations (contrast-enhanced computerized tomography abdomen, barium enema, and sigmoid biopsy) as well as upper gastrointestinal endoscopy, workup for secondary CIPO, esophageal and antroduodenal manometry, genetic studies, for primary CIPO. A laparotomy with concurrent adhesionolysis, appendectomy, gastrostomy, and ileostomy was undertaken, which included full-thickness biopsies at multiple sites. This revealed both degenerative leiomyopathy and eosinophilic myenteric ganglionitis (EMG). Known associations of CIPO, an underactive bladder, and sinus arrhythmias were also detected. Management: The infant was provided with supportive therapy. A trial of steroids was given for the EMG. The child had multiple bad prognostic factors and also protracted multiple nosocomial infections. He succumbed to his illness and complications after 40 days of hospitalization. Conclusion: The combination of EMG and degenerative leiomyopathy has not been reported in CIPO before.

BACKGROUND The presence and reactivation of chronic viral infections, such as EBV, CMV, and HIV, have been proposed as potential contributors to long COVID (LC), but studies in well-characterized postacute cohorts of individuals with COVID-19 over a longer time course consistent with current case definitions of LC are limited.METHODS In a cohort of 280 adults with prior SARS-CoV-2 infection, we assessed the presence and types of LC symptoms and prior medical history (including COVID-19 history and HIV status) and performed serological testing for EBV and CMV using a commercial laboratory. We used covariate-adjusted binary logistic regression models to identify independent associations between variables and LC symptoms.RESULTS We observed that LC symptoms, such as fatigue and neurocognitive dysfunction, at a median of 4 months following initial diagnosis were independently associated with serological evidence suggesting recent EBV reactivation (early antigen–diffuse IgG positivity) or high nuclear antigen (EBNA) IgG levels but not with ongoing EBV viremia. Serological evidence suggesting recent EBV reactivation (early antigen–diffuse IgG positivity) was most strongly associated with fatigue (OR = 2.12). Underlying HIV infection was also independently associated with neurocognitive LC (OR = 2.5). Interestingly, participants who had serologic evidence of prior CMV infection were less likely to develop neurocognitive LC (OR = 0.52).CONCLUSION Overall, these findings suggest differential effects of chronic viral coinfections on the likelihood of developing LC and association with distinct syndromic patterns. Further assessment during the acute phase of COVID-19 is warranted.TRIAL REGISTRATION Long-term Impact of Infection with Novel Coronavirus; ClinicalTrials.gov NCT04362150.FUNDING This work was supported by NIH/National Institute of Allergy and Infectious Diseases grants (3R01AI141003-03S1, R01AI158013, and K24AI145806); the Zuckerberg San Francisco General Hospital Department of Medicine and Division of HIV, Infectious Diseases, and Global Medicine; and the UCSF-Bay Area Center for AIDS Research (P30-AI027763).

BackgroundCarcinoid heart disease (CnHD) is a frequent cause of morbidity and mortality in patients with neuroendocrine tumors and carcinoid syndrome. Although valve replacement surgery appears to decrease all-cause mortality in patients with advanced CnHD, few studies have investigated the outcomes of patients after valve replacement.MethodsWe conducted a multi-institution retrospective registry of patients who received both tricuspid and pulmonic bioprosthetic valve (TV/PV) replacements for advanced CnHD from November 2005 to March 2021. Patients were followed post-operatively with echocardiographic studies every 3 months. Carcinoid valvular heart disease scores were used to monitor valve degeneration. Neuroendocrine tumor treatment, their administration times, and associations with echocardiographic findings were recorded.ResultsOf 87 patients with CnHD, 22 patients underwent simultaneous surgical TV and PV replacement. In 6 patients (27.3%), increased PV Vmax was the first echocardiographic manifestation of valve degeneration in the setting of occult neurohormonal release. Post-operative telotristat ethyl and peptide receptor radionuclide therapy appeared to stabilize PV Vmax. The PV Vmax showed consistent elevation in the entire patient population when compared to baseline, while bioprosthetic TV echocardiographic parameters were relatively unchanged throughout. Post-operative warfarin therapy did not affect the rate of PV degeneration, and no major bleeding was recorded during or after post-operative anticoagulation therapy.ConclusionBioprosthetic valve degeneration is common in CnHD. Monitoring with echocardiographic studies every 3 months, focusing on PV velocities, could identify patients with occult disease that very likely promotes valve degeneration. Novel neuroendocrine tumor therapies may have a beneficial impact on valve degeneration.