ABSTRACT
The current investigation delves into the convective heat and mass transfer characteristics of third-grade radiative nanofluid flow within a porous medium over a Riga plate configuration. The Riga plate structure incorporates magnets and electrodes strategically arranged on a plate surface. To enhance the accuracy of energy and concentration expressions within the third-grade fluid flow, the Cattano Christov Double Diffusion model is employed. Entropy generation analysis is conducted by applying the second law of thermodynamics, and Darcy's model is employed to characterize the behavior of a porous medium. Appropriate similarity transformations have been used to convert the partial differential equations monitoring the fluid flow model into dimensionless ordinary differential equations. The Galerkin weighted residual method is employed to resolve these equations numerically. The findings contain detailed explanations of how relevant factors affect the temperature field, concentration field, velocity field, entropy generation, and Bejan number, in addition to graphic representations of the results. The findings indicate that the medium's porosity and Brinkman number promote entropy generation. The Bejan number and entropy production is affected by the thermal radiation parameter, which first rises and then declines after a certain distance.
ABSTRACT
Background: Facial acanthosis nigricans (FAN) is an underrecognized and underdiagnosed entity. The typical presentation of acanthosis nigricans (AN) seen elsewhere on the body like axillae and groins is not seen on the face, making it mimic other pigmentary disorders. Moreover, FAN is seldom not accompanied with AN on the classical sites making the diagnosis challenging. The aims of this study were to determine clinical, dermoscopic, and histopathological features of FAN and to estimate the prevalence of obesity and insulin resistance (IR) in FAN. Methods: Forty cases of FAN and forty healthy nonobese individuals with comparable ages and gender were included in the study. Body mass index, waist circumference, hip circumference, waist to hip ratio, and serum fasting lipid levels were used to evaluate obesity, whereas serum fasting insulin and Homeostatic Model of Assessment of Insulin Resistance (HOMA-IR) were used to evaluate IR. Dermoscopy was performed in all cases. Histopathological features of the skin biopsies were reviewed. Results: Out of the 40 cases, 24 were male and 16 were female. The patterns of facial pigmentation in addition to the classic pattern were a hyperpigmented band over forehead (55%), periorbital darkening (25%), perioral (10%), and generalized darkening (10%). Dermoscopy in all cases revealed linear crista cutis, sulcus cutis, and hyperpigmented dots in crista cutis. Biopsy of 20 cases showed mild hyperkeratosis, acanthosis, papillomatosis, and increase in basal melanin. Clinico-dermoscopic-histological correlation showed that milder (light brown) variants of FAN had follicular plugging and subtle sulci pattern with irregular brown globules and perifollicular pigmentation on dermoscopy and mild hyperkeratosis and hypermelanization of the basal layer with minimal acanthosis and papillomatosis on histopathology. On the other hand, chronic variants (dark brown and black) showed prominent sulci, larger brown globules, and perifollicular hyperpigmentation on dermoscopy and moderate hyperkeratosis and hypermelanization of the basal layer with moderate to severe acanthosis and papillomatosis on histopathology. Fasting blood glucose, insulin, HOMA-IR, fasting serum triglyceride, and total cholesterol were statistically significantly high in cases in comparison with controls (P-value <0.05). Conclusions: Varied clinical presentations of FAN were observed. Dermoscopy and histopathology provide a good aid. FAN may be considered as a cutaneous marker of obesity and IR. Thus, FAN should be suspected in patients presenting with facial melanosis who are obese and have AN over other sites, although FAN can also present de novo.
ABSTRACT
INTRODUCTION: Coronavirus disease 2019 (COVID-19) was declared as pandemic and measures adopted for its control included quarantine of at-risk, isolation of infected along with other measures such as lockdown, restrictions on movement, and social interactions. Both the pandemic and these measures have the potential to cause mental health problems among individuals. OBJECTIVE: The present study aimed to investigate and estimate the prevalence of psychological well-being, particularly from an Indian perspective using systematic review and meta-analysis of existing literature. METHODS: We searched in the PubMed database, starting from the onset of the current pandemic and until 10th October 2020 to synthesize evidence on mental health outcomes from India. DerSimonian and Laird method of the random-effects meta-analysis was employed and heterogeneity between studies was assessed using the Chi-square based Cochran's Q statistic and I-squared (I2) statistics. RESULTS: The pooled prevalence of stress in nine studies was 60.7% (95% CI: 42.3%-77.7%), depression in eight studies was 32.7% (95% CI: 24.6%-41.3%), anxiety in six studies was 34.1% (95% CI: 26.3%-42.3%) and sleep disturbances in six studies was 26.7% (95% CI: 13.9%-41.8%). As expected, high heterogeneity was observed in the above-mentioned outcomes. Sub-group analysis showed that Health Care Workers (HCWs) had a higher prevalence of stress, anxiety, depression & psychological distress in comparison to the general population. CONCLUSION: A significant impact on psychological well-being during COVID-19 was observed in India as common adverse outcomes were stress (61%), psychological distress (43%), anxiety (34%), depression (33%), and sleep disturbances (27%). Thus the COVID-19 pandemic represents an unprecedented threat to mental health, which should become a priority for public health strategies.
