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1.
Sci Rep ; 14(1): 9138, 2024 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-38644366

RESUMEN

Phosphorene is a unique semiconducting two-dimensional platform for enabling spintronic devices integrated with phosphorene nanoelectronics. Here, we have designed an all phosphorene lattice lateral spin valve device, conceived via patterned magnetic substituted atoms of 3d-block elements at both ends of a phosphorene nanoribbon acting as ferromagnetic electrodes in the spin valve. Through First-principles based calculations, we have extensively studied the spin-dependent transport characteristics of the new spin valve structures. Systematic exploration of the magnetoresistance (MR) of the spin valve for various substitutional atoms and bias voltage resulted in a phase diagram offering a colossal MR for V and Cr-substitutional atoms. Such MR can be directly attributed to their specific electronic structure, which can be further tuned by a gate voltage, for electric field controlled spin valves. The spin-dependent transport characteristics here reveal new features such as negative conductance oscillation and switching of the sign of MR due to change in the majority spin carrier type. Our study creates possibilities for the design of nanometric spin valves, which could enable integration of memory and logic elements for all phosphorene 2D processors.

2.
Sci Rep ; 14(1): 4371, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38388641

RESUMEN

Transition metal oxides (TMO) are the preferred materials for metal ion battery cathodes because of their high redox potentials and good metal-ion intercalation capacity, which serve as an outstanding replacement for layered sulphide. In this work, using first-principles calculations based on Density functional theory approach, we explored the structural and electronic properties which comprise of adsorption and diffusion behaviour along with the analysis of voltage profile and storage capacity of Ru doped two-dimensional transition metal oxide [Formula: see text], [Formula: see text], and [Formula: see text] monolayers. The adsorption of alkali ions (Li, Na) to the surface of TMOs is strengthened by Ru-atom doping. Ru doping enhanced the adsorption energy of Li/Na-ion by 25%/11% for [Formula: see text], 8%/13% for [Formula: see text], and 10%/11% [Formula: see text] respectively. The open circuit voltage (OCV) also increases due to the high adsorption capacity of doped Monolayers. Ru doping makes the semiconducting TMOs conduct, which is suitable for battery application. As alkali ion moves closer to the dopant site, the adsorption energy increases. When alkali ions are close to the vicinity of doping site, their diffusion barrier decrease and rises as they go further away. Our current findings will be useful in finding ways to improve the storage performance of 2D oxide materials for application in energy harvesting and green energy architecture.

3.
Sci Rep ; 13(1): 16599, 2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37789039

RESUMEN

Semiconductors with controllable electronic transport coupled with magnetic behaviour, offering programmable spin arrangements present enticing potential for next generation intelligent technologies. Integrating and linking these two properties has been a long standing challenge for material researchers. Recent discoveries in two-dimensional (2D) magnet shows an ability to tune and control the electronic and magnetic phases at ambient temperature. Here, we illustrate controlled spin transport within the magnetic phase of the 2D semiconductor CrOBr and reveal a substantial connection between its magnetic order and charge carriers. First, we systematically analyse the strain-induced electronic behaviour of 2D CrOBr using density functional theory calculations. Our study demonstrates the phase transition from a magnetic semiconductor → half metal → magnetic metal in the material under strain application, creating intriguing spin-resolved conductance with 100% spin polarisation and spin-injection efficiency. Additionally, the spin-polarised current-voltage (I-V) trend displayed conductance variations with high strain-assisted tunability and a peak-to-valley ratio as well as switching efficiency. Our study reveals that CrOBr can exhibit highly anisotropic behaviour with perfect spin filtering, offering new implications for strain engineered magneto-electronic devices.

4.
Sci Rep ; 13(1): 13696, 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37608024

RESUMEN

Atomically thin two-dimensional (2D) Janus materials and their Van der Waals heterostructures (vdWHs) have emerged as a new class of intriguing semiconductor materials due to their versatile application in electronic and optoelectronic devices. Herein, We have invstigated most probable arrangements of different inhomogeneous heterostructures employing one layer of transition metal dichalcogenide, TMD (MoS2, WS2, MoSe2, and WSe2) piled on the top of Janus TMD (MoSeTe or WSeTe) and investigated their structural, electronic as well as optical properties through first-principles based calculations. After that, we applied twist engineering between the monolayers from 0[Formula: see text] 60[Formula: see text] twist angle, which delivers lattice reconstruction and improves the performance of the vdWHs due to interlayer coupling. The result reveals that all the proposed vdWHs are dynamically and thermodynamically stable. Some vdWHs such as MoS2/MoSeTe, WS2/WSeTe, MoS2/WSeTe, MoSe2/MoSeTe, and WS2/MoSeTe exhibit direct bandgap with type-II band alignment at some specific twist angle, which shows potential for future photovoltaic devices. Moreover, the electronic property and carrier mobility can be effectively tuned in the vdWHs compared to the respective monolayers. Furthermore, the visible optical absorption of all the Janus vdWHs at [Formula: see text] = 0[Formula: see text] can be significantly enhanced due to the weak inter-layer coupling and redistribution of the charges. Therefore, the interlayer twisting not only provides an opportunity to observe new exciting properties but also gives a novel route to modulate the electronic and optoelectronic properties of the heterostructure for practical applications.

5.
Front Genet ; 14: 1202135, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37359374

RESUMEN

Host genotype, early post-hatch feeding, and pre- and probiotics are factors known to modulate the gut microbiome. However, there is a knowledge gap on the effect of both chicken genotype and these dietary strategies and their interplay on fecal microbiome composition and diversity, which, in turn, can affect the release of endotoxins in the excreta of broilers. Endotoxins are a major concern as they can be harmful to both animal and human health. The main goal of the current study was to investigate whether it was possible to modulate the fecal microbiome, thereby reducing endotoxin concentrations in the excreta of broiler chickens. An experiment was carried out with a 2 × 2 × 2 factorial arrangement including the following three factors: 1) genetic strain (fast-growing Ross 308 vs. slower growing Hubbard JA757); 2) no vs. combined use of probiotics and prebiotics in the diet and drinking water; and 3) early feeding at the hatchery vs. non-early feeding. A total of 624 Ross 308 and 624 Hubbard JA757 day-old male broiler chickens were included until d 37 and d 51 of age, respectively. Broilers (N = 26 chicks/pen) were housed in a total of 48 pens, and there were six replicate pens/treatment groups. Pooled cloacal swabs (N = 10 chickens/pen) for microbiome and endotoxin analyses were collected at a target body weight (BW) of 200 g, 1 kg, and 2.5 kg. Endotoxin concentration significantly increased with age (p = 0.01). At a target BW of 2.5 kg, Ross 308 chickens produced a considerably higher amount of endotoxins (Δ = 552.5 EU/mL) than the Hubbard JA757 chickens (p < 0.01). A significant difference in the Shannon index was observed for the interaction between the use of prebiotics and probiotics, and host genotype (p = 0.02), where Ross 308 chickens with pre-/probiotics had lower diversity than Hubbard JA757 chickens with pre-/probiotics. Early feeding did not affect both the fecal microbiome and endotoxin release. Overall, the results suggest that the chicken genetic strain may be an important factor to take into account regarding fecal endotoxin release, although this needs to be further investigated under commercial conditions.

6.
Phys Rev Lett ; 129(11): 114801, 2022 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-36154426

RESUMEN

Premature relativistic transparency of ultrathin, laser-irradiated targets is recognized as an obstacle to achieving a stable radiation pressure acceleration in the "light sail" (LS) mode. Experimental data, corroborated by 2D PIC simulations, show that a few-nm thick overcoat surface layer of high Z material significantly improves ion bunching at high energies during the acceleration. This is diagnosed by simultaneous ion and neutron spectroscopy following irradiation of deuterated plastic targets. In particular, copious and directional neutron production (significantly larger than for other in-target schemes) arises, under optimal parameters, as a signature of plasma layer integrity during the acceleration.

7.
Rev Sci Instrum ; 93(5): 053303, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35649771

RESUMEN

Image plates (IPs) are a popular detector in the field of laser driven ion acceleration, owing to their high dynamic range and reusability. An absolute calibration of these detectors to laser-driven protons in the routinely produced tens of MeV energy range is, therefore, essential. In this paper, the response of Fujifilm BAS-TR IPs to 1-40 MeV protons is calibrated by employing the detectors in high resolution Thomson parabola spectrometers in conjunction with a CR-39 nuclear track detector to determine absolute proton numbers. While CR-39 was placed in front of the image plate for lower energy protons, it was placed behind the image plate for energies above 10 MeV using suitable metal filters sandwiched between the image plate and CR-39 to select specific energies. The measured response agrees well with previously reported calibrations as well as standard models of IP response, providing, for the first time, an absolute calibration over a large range of proton energies of relevance to current experiments.

8.
J Postgrad Med ; 68(3): 138-147, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35708395

RESUMEN

Objective: This study was undertaken to assess the change in social contact and transmission dynamics among adults in the Puducherry district during the different phases of country-wide lockdown. Methods: Adults aged 18-69 years in Puducherry were assessed for frequency and duration of contacts in the following time points: prior to lockdown (March 2020), during lockdown, immediate post-lockdown (April, June 2020), and seven months post-lockdown (February 2021). Adjusted incidence rate ratios (aIRR) were obtained using a generalized estimating equation. We also assessed the exponential trajectory of the time-varying reproduction number (Rt) during and after lockdown. Results: Compared to pre-lockdown phase, frequency of social contacts during 1st week, 4th week of lockdown, and immediate post-lockdown were reduced by 89% (aIRR = 0.11; 95% CI: 0.09-0.13), 40% (aIRR = 0.60; 95% CI: 0.52-0.69) and 91% (aIRR = 0.09; 95% CI: 0.07-0.10) respectively. However, the decline was not statistically significant at seven months post-lockdown. Correspondingly, we observed an initial spike in Rt during the lockdown phase followed by a gradual decline during the immediate post-lockdown phase. However, seven months post-lockdown, Rt has increased again. Conclusion: The study showed high compliance to the lockdown measures in Puducherry during the lockdown and immediate post-lockdown periods. However, as the lockdown measures were relaxed, the contact rate returned to the pre-lockdown state.


Asunto(s)
COVID-19 , Adulto , Control de Enfermedades Transmisibles , Humanos , Incidencia , India , Estudios Longitudinales , SARS-CoV-2
9.
SAR QSAR Environ Res ; 33(5): 357-386, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35380087

RESUMEN

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) outbreak is posing a serious public health threat worldwide in the form of COVD-19. Herein, we have performed two-dimensional quantitative structure-activity relationship (2D-QSAR) and three-dimensional pharmacophore modelling analysis employing inhibitors of 3-chymotrypsin-like protease (3CLpro), the leading protease that is crucial for the replication of SARS-CoV-2. The investigation aims to identify the important structural features responsible for the enzyme inhibition and the search for novel 3CLpro enzyme inhibitors as effective therapeutics for treating SARS-CoV-2. Furthermore, we carried out molecular docking studies using the most and least active compounds in the dataset, aiming to validate the contributions of various features as appeared in the QSAR models. Later, the stringently validated 2D-QSAR model was used to estimate the 3CLpro inhibitory activity of compounds from five chemical databases. Compounds with the significant predicted activity were then subjected to pharmacophore-based virtual screening to screen the top-rated compounds, which were then further subjected to molecular docking analysis, absorption, distribution, metabolism, excretion - toxicity (ADMET) profiling, and molecular dynamics (MD) simulation. The multi-step virtual screening analyses suggested that compounds CASAntiV-865453-58-3, CASAntiV-865453-40-3, and CASAntiV-2043031-84-9 could be used as effective therapeutic agents for the treatment of SARS-CoV-2.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , SARS-CoV-2 , Antivirales/química , Antivirales/farmacología , Antivirales/uso terapéutico , Humanos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Inhibidores de Proteasas/química , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasas/uso terapéutico , Relación Estructura-Actividad Cuantitativa
10.
Rev Sci Instrum ; 93(3): 033304, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35364990

RESUMEN

The response of the BAS-TR image plate (IP) was absolutely calibrated using a CR-39 track detector for high linear energy transfer Au ions up to ∼1.6 GeV (8.2 MeV/nucleon), accelerated by high-power lasers. The calibration was carried out by employing a high-resolution Thomson parabola spectrometer, which allowed resolving Au ions with closely spaced ionization states up to 58+. A response function was obtained by fitting the photo-stimulated luminescence per Au ion for different ion energies, which is broadly in agreement with that expected from ion stopping in the active layer of the IP. This calibration would allow quantifying the ion energy spectra for high energy Au ions, which is important for further investigation of the laser-based acceleration of heavy ion beams.

11.
Poult Sci ; 101(6): 101869, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35477136

RESUMEN

The fatty acid content of microalgae, especially the high content of omega-3 fatty acids such as eicosapentaenoic acid (EPA, C20:5) and docosahexaenoic acid (DHA, C22:6), could enrich eggs when fed to laying hens. Moreover, the properties and bioactive components of omega-3 fatty acids could positively influence the health and production performance of laying hens. In this study, the effects of dried Nannochloropsis limnetica inclusions in diets on yolk omega-3 fatty acid content, laying hen performance, nutrient retention, intestinal morphometry and systemic inflammatory markers were measured. A total of 240 twenty-five-wk-old laying hens were randomly assigned to 5 treatments distributed among 30 pens. Treatment A received the reference diet, while diets in treatments B, C, and D contained the control diet with 1, 2, and 3% microalgae added, respectively. In treatment E, a portion of ingredients of the control diet was replaced with rapeseed meal to induce a mild nutritional challenge, along with an inclusion of 3% microalgae. Compared to the control group the rate of lay increased by approximately 5% (P = 0.039) when birds were fed 2 or 3% microalgae. Furthermore, inclusion of 2 and 3% microalgae resulted in higher feed intake compared to the control group (126, 125, and 119 g/hen/d respectively; P = 0.001). Other performance parameters such as nutrient retention and egg characteristics were not affected by the dietary treatments. The EPA and DHA content of the yolk increased with increasing microalgae inclusion level (P < 0.001). A 2% algal inclusion resulted in 58.3 (EPA) and 603 (DHA) mg per 100 g dry yolk, respectively. Plasma haptoglobin levels of laying hens in both treatments receiving 3% microalgae were almost 3 times lower compared to the control group (1.25 and 1.62 vs. 5.60; P < 0.001), regardless of the inclusion of rapeseed in the diet. Based on these results, it can be concluded that the inclusion of N. limnetica enriches the egg yolk without negatively affecting the performance of laying hens and egg characteristics. Due to the positive effect on feed intake, microalgae in the diet provide nutritional benefits for laying hens. However, the positive effects of microalgae, especially on the health of laying hens, warrants further research.


Asunto(s)
Chlorophyta , Ácidos Grasos Omega-3 , Microalgas , Estramenopilos , Alimentación Animal/análisis , Animales , Pollos , Dieta/veterinaria , Suplementos Dietéticos , Ácidos Docosahexaenoicos , Yema de Huevo , Huevos , Ácidos Grasos , Femenino , Nutrientes , Óvulo
14.
Mymensingh Med J ; 31(1): 234-236, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34999708

RESUMEN

Severe Coronavirus disease 2019 (COVID-19) is a multi-systemic disease which presents with respiratory, gastrointestinal or musculoskeletal symptoms. Patients also display myriad post-COVID19 symptoms which range from myalgia to depression. We present case series of unusual and unreported post-COVID19 feature in nine cases who had recovered completely but developed pedal oedema which could not be attributed to any other organic cause. These COVID-19 cases were examined in out-patient department for various post-COVID-19 symptoms at tertiary care centers in North India and Bangladesh from July 2020 to February 2021. Ethical clearance was taken and consent obtained from each patient included in this case series.


Asunto(s)
COVID-19 , Edema/diagnóstico , Edema/etiología , Humanos , India , SARS-CoV-2 , Centros de Atención Terciaria
15.
J Postgrad Med ; 68(1): 14-23, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34531334

RESUMEN

INTRODUCTION: Epidemiological transition remains a key contributor to the rising prevalence of non-communicable diseases (NCDs) across developing nations. Population-specific NCD risk factors estimates derived using World Health Organization (WHO) 'STEP-wise approach' are crucial for devising evidence-based public health interventions to combat NCDs. OBJECTIVE: To estimate the prevalence of behavioral and biological risk factors for NCDs among the rural adult population of Puducherry district in India. METHODOLOGY: STEPS survey was conducted by following all three steps (behavioral, physical measurements and biochemical risk factors) of NCD risk factor assessment. A total of 790 participants were selected from 50 villages through multistage cluster sampling method. STEPS instrument was used to assess behavioral risk factors, physical measurements and biochemical (fasting blood glucose and total cholesterol) risk factors. RESULTS: Tobacco use and alcohol consumption were present among 11.3% (95% Confidence Interval (CI): 9-13.6%) and 19.2% (95% CI: 16.5-22.4%) of the population, respectively. Low physical activity, inadequate intake of fruits and vegetables, overweight and obesity were observed among 29.3% (95% CI: 26.2-32.7%), 89.8% (95% CI: 87.6-92%), 15.6% (95% CI: 13.1-18.3%) and 38.9% (95% CI: 35.4-42.2%), respectively. About 28.2% (95% CI: 25.2-31.6%) had hypertension and 24.4% (95% CI: 20-29%) had diabetes mellitus. Abdominal obesity was twice highly prevalent among women. Tobacco and alcohol use were more common among men, whereas low physical activity, obesity and hypercholesterolemia were higher among women. CONCLUSION: Public health interventions to promote healthy lifestyle need to be initiated especially to increase physical activity, intake for fruits and vegetables, and quitting of tobacco and alcohol consumption in the rural population of Puducherry.


Asunto(s)
Hipertensión , Enfermedades no Transmisibles , Adulto , Consumo de Bebidas Alcohólicas/epidemiología , Estudios Transversales , Femenino , Humanos , Hipertensión/epidemiología , Masculino , Enfermedades no Transmisibles/epidemiología , Sobrepeso/epidemiología , Prevalencia , Factores de Riesgo , Población Rural
16.
Phys Rev Lett ; 127(19): 194801, 2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34797126

RESUMEN

We report on the selective acceleration of carbon ions during the interaction of ultrashort, circularly polarized and contrast-enhanced laser pulses, at a peak intensity of 5.5×10^{20} W/cm^{2}, with ultrathin carbon foils. Under optimized conditions, energies per nucleon of the bulk carbon ions reached significantly higher values than the energies of contaminant protons (33 MeV/nucleon vs 18 MeV), unlike what is typically observed in laser-foil acceleration experiments. Experimental data, and supporting simulations, emphasize different dominant acceleration mechanisms for the two ion species and highlight an (intensity dependent) optimum thickness for radiation pressure acceleration; it is suggested that the preceding laser energy reaching the target before the main pulse arrives plays a key role in a preferential acceleration of the heavier ion species.

17.
Mymensingh Med J ; 30(4): 1051-1059, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34605476

RESUMEN

Neutrophil Gelatinase-Associated Lipocalin (NGAL) is rapidly released by renal tubules after injury, potentially allowing early identification of acute kidney injury (AKI) after cardiac surgery. However, the diagnostic performance of NGAL has varied widely in clinical studies and it remains unknown what factors modify the relationship between NGAL and AKI. The main objective of the study was to determine the efficacy of NGAL in early detection of AKI among the CABG patients undergoing cardiopulmonary bypass (CPB). This prospective observational study was conducted in the Department of Nephrology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh in collaboration with the Department of Biochemistry, BSMMU among 42 patients admitted into the Department of Cardiac Surgery, Ibrahim Cardiac Hospital and Research Institute, Dhaka Bangladesh from July 2014 to June 2015. For the measurement of NGAL, urine samples were obtained before surgery and 6 hours after commencement of CPB. Serum creatinine was measured preoperatively and 6, 24 and 48 hours postoperatively. Increase in the serum creatinine level at 6, 24 and 48 hours after surgery was used to analyze the diagnostic value of urinary NGAL. In this study 42 CABG patients with no known renal insufficiency planned to have CPB were included. Receiver-operator characteristic (ROC) was constructed by using NGAL, which gave a cut off value of ≥185.90ng/ml. Eight patients were AKI positive among them 6(75.0%) patients were NGAL positive and 2(25.0%) were NGAL negative. Diagnosis of AKI was delayed by 24-48 hours by serum creatinine measurement. This study has demonstrated that level of urinary NGAL concentration at 6 hours post CPB increased before the increase of serum creatinine level and NGAL is an early predictor of AKI in adult cardiac surgical patients. The early detection of renal injury by NGAL may allow earlier intervention in patients with high risk for AKI.


Asunto(s)
Lesión Renal Aguda , Puente Cardiopulmonar , Lesión Renal Aguda/diagnóstico , Lesión Renal Aguda/etiología , Proteínas de Fase Aguda , Adulto , Bangladesh , Biomarcadores , Puente Cardiopulmonar/efectos adversos , Puente de Arteria Coronaria , Creatinina , Humanos , Lipocalina 2 , Lipocalinas , Valor Predictivo de las Pruebas , Proteínas Proto-Oncogénicas
18.
Phys Rev E ; 104(2-2): 025210, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34525575

RESUMEN

Laser-driven ion acceleration has attracted global interest for its potential towards the development of a new generation of compact, low-cost accelerators. Remarkable advances have been seen in recent years with a substantial proton energy increase in experiments, when nanometer-scale ultrathin foil targets and high-contrast intense lasers are applied. However, the exact acceleration dynamics and particularly the ion energy scaling laws in this novel regime are complex and still unclear. Here, we derive a scaling law for the attainable maximum ion energy from such laser-irradiated nanometer-scale foils based on analytical theory and multidimensional particle-in-cell simulations, and further show that this scaling law can be used to accurately describe experimental data over a large range of laser and target parameters on different facilities. This provides crucial references for parameter design and experimentation of the future laser devices towards various potential applications.

20.
Heliyon ; 7(6): e07330, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34189330

RESUMEN

In this paper, we introduce the notions of certain classes of soft ideals in soft ternary semigroups and study some inter-relations between different types of soft ideals in a soft ternary semigroup. We also characterize completely regular soft ternary semigroups with the help of these soft ideals of soft ternary semigroups.

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