6 research outputs found
Photocatalytic and thermoelectric performance of asymmetrical two-dimensional Janus aluminum chalcogenides
No full textThrough a density functional theory-driven survey, a comprehensive investigation of two-dimensional (2D) Janus aluminum-based monochalcogenides (Al2XY with X/Y = S, Se, and Te) has been performed within this study. To begin with, it is established that the examined phase, in which the Al-atoms are located at the two inner planes while the (S, Se, and Te)-atoms occupy the two outer planes in the unit cell, are energetically, mechanically, dynamically, and thermally stable. To address the electronic and optical properties, the hybrid function HSE06 has been employed. It is at first revealed that all three monolayers display a semiconducting nature with an indirect band gap ranging from 1.82 to 2.79 eV with a refractive index greater than 1.5, which implies that they would be transparent materials. Furthermore, the monolayers feature strong absorption spectra of around 105 cm−1 within the visible and ultraviolet regions, suggesting their potential use in optoelectronic devices. Concerning the photocatalytic performance, the conduction band-edge positions straddle the hydrogen evolution reaction redox level. Also, it is observed that the computed Gibbs free energy is around 1.15 eV, which is lower and comparable to some recently reported 2D-based Janus monolayers. Additionally, the thermoelectric properties are further investigated and found to offer a large thermal power as well as a high figure of merit (ZT) around 1.03. The aforementioned results strongly suggest that the 2D Janus Al-based monochalcogenide exhibits suitable characteristics as a potential material for high-performance optoelectronic and thermoelectric applications.Team Poulumi De
Structures, stabilities, optoelectronic and photocatalytic properties of Janus aluminium mono-chalcogenides Al(Ga, In)STe monolayers
No full textComputational design of new two-dimensional materials constitutes an effective and promising approach in the development and exploration of a wide range of emerging applications such as optoelectronics, photocatalysis, energy storage, and conversion. Within the framework of this work, we systematically investigated for the first time, the structural, stability, optoelectronic, and pho-tocatalytic properties of new predicted Al(Ga, In)STe monolayers derived from Janus Aluminium mono-chalcogenides through Density Functional Theory and Ab-Initio molecular dynamic simulations. After a full optimization of both struc-tures, their dynamics and thermal stability was confirmed through the calculations of phonon spectrum and ab-initio molecular dynamics at a chosen temperature, respectively. Subsequently, the electronic and optical properties were explored and findings revealed that both monolayers exhibit a semiconducting characteristic with a direct and indirect electronic band gap of about 2.23 and 2.69 eV using HSE06 hybrid functional for AlGaSTe and AlInSTe monolayers, re-spectively. Furthermore, the optical absorption indicates a strong absorption of light in the range between 3 and 18 eV. More noticeably, Both Janus monolayers considered exhibiting a promising optical absorption in the visible wavelength region with an absorption coefficient greater than 105 cm−1. In addition, the photocatalytic properties of these structures were investigated by plotting the band edge positions straddle the reduction potential of H2 and the oxidation potential H2O. Based on our results, we conclude that both monolayers offer good thermodynamic stability allowing them to be processed experimentally and can be used as very appropriate candidates for optoelectronics and photocatalytic applications.</p
The Role of Lipolysis in Regulating Plasma Glucose Concentrations in Mourning Doves
No full textabstract: Birds have unusually high plasma glucose concentrations compared to mammals of similar size despite their high metabolic rate. While birds use lipids as their main source of energy, it is still unclear how and why they maintain high plasma glucose concentrations. To investigate a potential underlying mechanism, this study looks at the role of lipolysis in glucose homeostasis. The purpose of this study is to examine the effects of decreased glycerol availability (through inhibition of lipolysis) on plasma glucose concentrations in mourning doves. The hypothesis is that decreased availability of glycerol will result in decreased production of glucose through gluconeogenesis leading to reduced plasma glucose concentrations. In the morning of each experiment, mourning doves were collected at the Arizona State University Tempe campus, and randomized into either a control group (0.9% saline) or experimental group (acipimox, 50mg/kg BM). Blood samples were collected prior to treatment, and at 1, 2, and 3 hours post-treatment. At 3 hours, doves were euthanized, and tissue samples were collected for analysis. Acipimox treatment resulted in significant increases in blood glucose concentrations at 1 and 2 hours post- treatment as well as renal triglyceride concentrations at 3 hours post-treatment. Change in plasma free glycerol between 0h and 3h followed an increasing trend for the acipimox treated animals, and a decreasing trend in the saline treated animals. These results do not support the hypothesis that inhibition of lipolysis should decrease blood glycerol and blood glucose levels. Rather, the effects of acipimox in glucose homeostasis appear to differ significantly between birds and mammals suggesting differing mechanisms for glucose homeostasis
Geometric immunosuppression in CAR T-cell treatment : Insights from mathematical modeling
No full textPublisher Copyright: © 2025 The Author(s)Chimeric antigen receptor T (CAR T) cell therapy has emerged as a promising treatment for hematological malignancies, offering a targeted approach to cancer treatment. Understanding the complexities of CAR T-cell therapy within solid tumors poses challenges due to the intricate interactions within the tumor microenvironment. Mathematical modeling may serve as a valuable tool to unravel the dynamics of CAR T-cell therapy and improve its effectiveness in solid tumors. This study aimed to investigate the impact of spatial aspects in CAR T therapy of solid tumors, utilizing cellular automata for modeling purposes. Our main objective was to deepen our understanding of treatment effects by analyzing scenarios with different spatial distributions and varying the initial quantities of tumor and CAR T-cells. Tumor geometry significantly influenced treatment efficacy in-silico, with notable differences observed between tumors with block-like arrangements and those with sparse cell distributions, leading to the concept of immune suppression due to geometrical effects. This research delves into the intricate relationship between spatial dynamics and the effectiveness of CAR T therapy in solid tumors, highlighting the relevance of tumor geometry in the outcome of cellular immunotherapy treatments. Our results provide a basis for improving the efficacy of CAR T-cell treatments by combining them with other ones reducing the density of compact tumor areas and thus opening access ways for tumor killing T-cells.Peer reviewe
Physical activity in relation to metabolic health and obesity: The Feel4Diabetes study
No full textAim: To examine physical activity levels in association with metabolic health and estimate the stability of metabolically healthy obese (MHO) phenotypes over a 2-year period. Methods: In total, 2848 men and women from families at risk of the development of diabetes were recruited. Participants were classified as obese or non-obese and metabolic health was defined using five existing definitions. Physical activity was estimated with the International Physical Activity Questionnaire and pedometers. Results: Prevalence of the MHO phenotype varied among definitions (0% to 20.2%). Overall, the MHO were more active than the metabolically unhealthy obese (MUO). Daily sitting hours (odds ratio [OR] = 1.055, 95% confidence interval [CI]: 1.009-1.104) and daily steps (per 500; OR = 0.934, 95% CI: 0.896-0.973) were remarkable predictors of metabolic health in individuals with obesity; and likewise, in individuals without obesity. After 2 years, 44.1% of baseline MHO adults transitioned to MUO, while 84.0% of the MUO at baseline remained at the same phenotype. Although physical activity was not a major determinant in phenotype transitioning, daily steps were associated with the maintenance of metabolic health over time in the non-obese group. Conclusion: A universally accepted definition for MHO is needed. Being physically active can contribute to a metabolically healthy profile even in the presence of obesity; still, MHO is a transient condition and physical activity alone may not be an adequate factor for its maintenance. © 2024 The Author(s). Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd
Systematic analysis of authorship demographics in global surgery
No full textBackground Global surgery has recently gained prominence as an academic discipline within global health. Authorship inequity has been a consistent feature of global health publications, with over-representation of authors from high-income countries (HICs), and disenfranchisement of researchers from low-income and middle-income countries (LMICs). In this study, we investigated authorship demographics within recently published global surgery literature.Methods We performed a systematic analysis of author characteristics, including gender, seniority and institutional affiliation, for global surgery studies published between 2016 and 2020 and indexed in the PubMed database. We compared the distribution of author gender and seniority across studies related to different topics; between authors affiliated with HICs and LMICs; and across studies with different authorship networks.Results 1240 articles were included for analysis. Most authors were male (60%), affiliated only with HICs (51%) and of high seniority (55% were fully qualified specialist or generalist clinicians, Principal Investigators, or in senior leadership or management roles). The proportion of male authors increased with increasing seniority for last and middle authors. Studies related to Obstetrics and Gynaecology had similar numbers of male and female authors, whereas there were more male authors in studies related to surgery (69% male) and Anaesthesia and Critical care (65% male). Compared with HIC authors, LMIC authors had a lower proportion of female authors at every seniority grade. This gender gap among LMIC middle authors was reduced in studies where all authors were affiliated only with LMICs.Conclusion Authorship disparities are evident within global surgery academia. Remedial actions to address the lack of authorship opportunities for LMIC authors and female authors are required
