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1.
Heliyon ; 10(18): e37689, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39309917

RESUMEN

The co-doping of vanadium pentoxide (V2O5) with rare-earth (RE) elements, namely 1.5 % holmium (Ho) and 1.5 % ytterbium (Yb) has been conducted using an eco-friendly, straightforward hydrothermal approach to assess the combined effects on structural, optical, and photocatalytic properties. The application of the density functional theory (DFT) approach effectively examined the impact of RE ions on the photocatalytic efficiency of co-doped V2O5. The stable orthorhombic crystal structure of co-doped V2O5 has been confirmed using DFT and X-ray diffraction without a secondary phase. It appears that homogeneous nucleation occurs while heterogeneous nucleation slows down in co-doped samples, as evidenced by the larger crystallite sizes in co-doped samples compared to doped ones. It means a result, the co-doped samples exhibit photodegrades more quickly and have a higher rate constant than the doped samples. This is because they have less dislocation density (4.26 × 10-3 nm-2) and internal micro-strain (4.93 × 10-3). The bandgap and degradation efficiency are determined by the UV-vis spectroscopy and found to be 2.33 eV and 95 %, respectively, at the optimal pH of 7 in the visible range. The co-doped sample has a rate constant of 24 × 10-3 min-1, which is the highest in the RE-doped V2O5 system. This is a good reason to think of co-doped V2O5 as a possible catalyst.

2.
RSC Adv ; 12(51): 32994-33007, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36425165

RESUMEN

High-hardness materials with ductile deformation behavior have recently piqued interest due to their prospective applications, particularly as hard and protective coatings. The crack formation, especially in metal and ceramic materials, is one of the biggest problems of the surface hard coatings on heavy-duty tools. In this regard, mechanical properties (Vickers hardness, fracture toughness, machinability index, index of brittleness, as well as Pugh's ratio) have been studied for the metallic boro-carbides of A2BC (A = Ti, Zr, Hf, and W) compounds using the state-of-the-art density functional theory in detail. The compounds under investigation are both thermodynamically and mechanically stable. The value of Vickers hardness (in GPa) for A2BC (A = Ti, Zr, Hf, and W) compounds are 28.20, 23.12, 12.44, and 35.70, respectively, which indicates the W2BC could be a member of the hard family (H v > 30 GPa). Pugh's ratio suggests ductile deformation for the W2BC compound, whereas the other three (Ti2BC, Zr2BC, and Hf2BC) compounds exhibit brittle deformation behavior. The W2BC compounds have the highest ductility among the other metallic boro-carbides (M2BC; M = V, Nb, Mo and Ta) and some other benchmark coating materials (TiN, TiAlN, C-BN, and Cr0.5Al0.5N). The fracture toughness (K IC) values are in the following sequence: Zr2BC < Ti2BC < Hf2BC < W2BC, which indicates that, the highest resistance (K IC = 4.96 MPam1/2) found for W2BC is suitable to prevent the crack propagation within the solid. In addition, the structural, electronic, optical, and thermal properties are also investigated for the A2BC (A = Ti, Zr, Hf, and W) compounds. The Ti2BC (W2BC) reflectivity spectra never fall below 53 (45)% in the 0 to 10.3 eV (0 to 16.70 eV) photon energy range, suggesting that these compounds have promise for usage as coating materials to reduce solar heating. Hf2BC and W2BC compounds could also be exploited as promising thermal barrier coating materials, while Ti2BC could be used as heat sink material based on the results of Debye temperature, melting temperature, thermal conductivity, and thermal expansion coefficient. The electronic properties reveal the metallic behavior of these compounds. The results obtained here are compared with those of some commercially known compounds, where available.

3.
Phys Chem Chem Phys ; 24(48): 29640-29654, 2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36449332

RESUMEN

LaIr3Ga2 is a kagome superconductor with a superconducting temperature (Tc) of 5.16 K. Here, we present the physical properties of the LaIr3Ga2 kagome superconductor computed via the DFT method wherein six different exchange-correlation functionals were used. The lattice parameters obtained using different functionals are reasonable, with a slight variation compared to experimental values. The bonding nature was explored. The elastic constants (Cij), moduli (B, G, Y), and Vickers hardness (Hv) were computed to disclose the mechanical behavior. The Hv values were estimated to be 2.56-3.16 GPa using various exchange-correlation functionals, indicating the softness of the kagome material. The Pugh ratio, Poisson's ratio, and Cauchy pressure revealed the ductile nature. In addition, mechanical stability was ensured based on the estimated elastic constants. The anisotropic mechanical behavior was confirmed via different anisotropic indices. The Debye temperature (ΘD), melting temperature (Tm), and minimum thermal conductivity (kmin) were calculated to characterize the thermal properties and predict the potential of LaIr3Ga2 as a thermal barrier coating material. The electronic density of states was investigated in detail. The McMillan equation was used to estimate Tc, and the electron-phonon coupling constant (λ) was calculated to explore the superconducting nature. The important optical constants were also calculated to explore its possible optoelectronic applications. The values of reflectivity in the IR-visible region are about 62% to 80%, indicating that the compound under study is suitable as a coating to reduce solar heating. The obtained parameters were compared with previously reported parameters, where available.

4.
Glob Ment Health (Camb) ; 9: 146-156, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36618722

RESUMEN

Background: We assessed the feasibility of implementing psychological counseling services (PCS) for mothers of children with autism spectrum disorders (ASD) integrated within special education settings in urban Bangladesh. Method: In two special education schools for ASD in Dhaka City, trained female psychologists screened mothers using the Patient Health Questionnaire (PHQ-9). PCS was administered to all the mothers irrespective of a diagnosis of depression. Mothers with a PHQ-9 score >4 who met criteria for a major depressive episode (MDE) based on the DSM-IV Structured Interview Axis I Disorders (SCID-I) were also administered skill-building training through monthly home visits to support ASD care. The level of depression was assessed by the Depression Measurement Scale (DMS), and quality of life (QoL) was measured by Visual Analogue Scale (VAS) of EQ5D5L scale before and after PCS. Result: Among 188 mothers enrolled in the study, 81 (43%) received PCS, and 27.1% (22) had MDE. In the first month, 73 sessions were scheduled and 60 completed (85%). In the last month, 53 sessions were scheduled and 52 completed (98%). The mean DMS score decreased from 79.5 ± 23 to 60 ± 20 (p = 0.004), and DMS scores were significantly higher among mothers with MDE (97.8 ± 12.1 v. 69.9 ± 22.1; p < 0.001) compared to those without MDE (72.7 ± 22.6 v. 56.1 ± 18.1; p = 0.003). The mean VAS score improved from 70.3 ± 14.1 to 80.2 ± 13.3 (p = 0.001) between the first and the last session. Changes in DMS were negatively correlated with changes in VAS scores (ß: -0.213, 95% CI 0.370 to -0.056). Conclusion: Within special education schools for ASD in urban Bangladesh, it was feasible to administer an integrated program of PCS for mothers of children with ASD by trained psychologists who were able to screen and intervene to reduce their level of depression and improve their quality of life.

5.
Front Public Health ; 9: 704726, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34552906

RESUMEN

Background: The negative impact of COVID-19 on mental health has been reported by media throughout the world, although this role is not well-understood in low-and middle-income countries (LMIC). We examined the reporting of mental health issues during the COVID-19 pandemic in Bangladesh and initiatives undertaken to support mental health reported from the viewpoint of media. Methods: We reviewed articles published in 10 local newspapers, including seven Bangla and three English newspapers, during the first year of the COVID-19 pandemic. News topics were identified through discussions among the team members, with searches across online newspapers and portals. Data extrapolated from newspapers were documented in an Excel spreadsheet. A mixed-method approach was used following a framework analysis for analyzing data. Recurring issues and commonly emerging topics were generated from the data. Descriptive statistics were applied for analyzing quantitative data. Results: Between March 2020 and March 2021, we have identified 201 reports on mental health issues including 45 reports (22.4%) focused on stress due to the associated financial crisis, unemployment and loneliness, 50 reports (24.9%) of 80 apparent suicides linked to family issues, disharmony in conjugal relationships, harassment, sexual violence, emotional breakdown, financial crisis, and stigma due to COVID-19.There were 77 reports (38.3%) concerning domestic violence during the pandemic. Twenty-nine reports (14.4%) referenced actions taken by different organizations to address mental health issues in response to the pandemic in Bangladesh. Conclusion: News coverage has the scope to highlight important issues that can emerge as a consequence of the COVID-pandemic, such as mental health, in a low resource setting. Capacity building of the media on the way to report mental health issues during emergency situations could be a useful strategy for more credible reporting on mental health issues during the COVID-19 pandemic for raising awareness of the public and policymakers about the negative consequences on mental health of the COVID-19 pandemic in Bangladesh. Adopting policies to support essential mental health care and promoting the local organizations to take timely public health measures will be imperative for averting the negative consequences of mental health due to the COVID-19 pandemic in Bangladesh.


Asunto(s)
COVID-19 , Suicidio , Bangladesh/epidemiología , Humanos , Salud Mental , Pandemias , SARS-CoV-2
6.
J Econ Entomol ; 114(4): 1470-1479, 2021 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-34231849

RESUMEN

Climate change-induced salinity intrusion into agricultural soils is known to negatively impact crop production and food security. However, the effects of salinity increase on plant-herbivore-natural enemy systems and repercussions for pest suppression services are largely unknown. Here, we examine the effects of increased salinity on communities of rice (Oryza sativa), brown planthopper (BPH), Nilaparvata lugens, and green mirid bug (GMB), Cyrtorhinus lividipennis, under greenhouse conditions. We found that elevated salinity significantly suppressed the growth of two rice cultivars. Meanwhile, BPH population size also generally decreased due to poor host plant quality induced by elevated salinity. The highest BPH density occurred at 2.0 dS/m salinity and declined thereafter with increasing salinity, irrespective of rice cultivar. The highest population density of GMB also occurred under control conditions and decreased significantly with increasing salinity. Higher salinity directly affected the rice crop by reducing plant quality measured with reference to biomass production and plant height, whereas inducing population developmental asynchrony between BPH and GMB observed at 2 dS/m salinity and potentially uncoupling prey-predator dynamics. Our results suggest that increased salinity has harmful effects on plants, herbivores, natural enemies, as well as plant-pest-predator interactions. The effects measured here suggest that the bottom-up effects of predatory insects on rice pests will likely decline in rice produced in coastal areas where salinity intrusion is common. Our findings indicate that elevated salinity influences tritrophic interactions in rice production landscapes, and further research should address resilient rice insect pest management combining multipests and predators in a changing environment.


Asunto(s)
Hemípteros , Heterópteros , Oryza , Animales , Herbivoria , Conducta Predatoria , Salinidad
7.
Mymensingh Med J ; 30(1): 101-105, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33397858

RESUMEN

Free flap reconstruction after surgical ablation of head & neck cancer greatly improve the surgical outcome. Microvascular anastomosis is an important part of Microsurgery and it is not widely practiced in every center. A retrospective review was conducted in the Head & Neck Division of Otolaryngology-Head & Neck Surgery Department, Bangabandhu Sheikh Mujib Medical University (BSMMU), Bangladesh from May 2016 to June 2017. Total 20 patients with head & neck cancer had been treated surgically between this period and 14 patients were reconstructed with free flap. The focus of this study is to establish the surgical outcome, which is more with free flap reconstruction in the patients previously diagnosed as head & neck cancer. We reconstructed 14 cases of oral cavity carcinoma (Stage IV) with the free flap. Majority cases were carcinoma involving the buccal mucosa with retromolar trigone (36%) followed by buccal mucosa (22%), buccal mucosa with lower alveolus (21%), carcinoma tongue with floor of the mouth (14%) and floor of the mouth (7%). Radial forearm freflap (RFFF) were commonly used in 10 cases (71.4%) and Anterolateral thigh flap (ALT) used in four cases (21.5%). Partial flap loss was seen in one case and wound infection occurred in another case but both were managed successfully with postoperative dressing and debridement. Microvascular free flap reconstruction can be a good choice after surgical removal of the head & neck cancer diseases and it should be practiced in every well-equipped tertiary medical center with the help of properly trained surgeon.


Asunto(s)
Colgajos Tisulares Libres , Neoplasias de Cabeza y Cuello , Procedimientos de Cirugía Plástica , Bangladesh , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Estudios Retrospectivos , Universidades
8.
Nat Prod Res ; 35(16): 2793-2798, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31578877

RESUMEN

The WSE is a highly polar, gummy and mucilaginous bioactive content of the Nigella sativa (L.) seeds. This study reports the anxiolytic and anti-inflammatory effects of WSE investigated using Elevated Plus Maze (EPM) and Hole-Board Test (HBT) in adult mice and human RBCs haemolysis inhibition and protein denaturation respectively. The oral WSE treatment (100 & 200 mg/kg b.w/day) for 72 hours has exhibited slightly better anxiolytic effect (p < 0.05) through the time span (92.33 & 93.33 s) spent in the opened arms of EPM vs. diazepam (1 mg/kg b.w i.p/day; 69.33 s). In HBT, only WSE (200 mg/kg b.w/day) has shown a promising number of mean head pokes (13.27 times/min) vs. diazepam (12.87 times/min). The WSE (62.5-500 µg/mL) exposure has exhibited 40.14-72.18% protection against lysis of RBCs vs. aspirin (57.04-71.48%) whilst 62.67-67.66% inhibition of protein denaturation vs. diclofenac sodium (43.11-80.64%). The current findings suggested WSE has promising anxiolytic and anti-inflammatory activities.


Asunto(s)
Ansiolíticos , Antiinflamatorios , Nigella sativa , Animales , Ansiolíticos/aislamiento & purificación , Ansiolíticos/farmacología , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/farmacología , Ansiedad/tratamiento farmacológico , Eritrocitos/efectos de los fármacos , Humanos , Aprendizaje por Laberinto , Ratones , Nigella sativa/química , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Extractos Vegetales/farmacología , Semillas/química
9.
Mymensingh Med J ; 29(1): 149-155, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31915351

RESUMEN

Reconstruction of total lip is a challenging task for a plastic surgeon. It becomes more complicated when there is loss of additional tissues like angle of mouth, buccal mucosa or floor of the mouth. Radial forearm flap with palmaris longus tendon provides an easier but reliable technique for three dimensional lip reconstructions with good functional and aesthetic outcome. In this short observational series we included 5 patients of total lip reconstruction and conducted at Sylhet MAG Osmani Medical College Hospital and Private Clinic of Sylhet, Bangladesh from January 2014 to December 2017. Among these one was a case of basal cell carcinoma of upper lip and rest was squamous cell carcinoma of lower lip. The mean age was 71 years. All the flaps survived and patients had normal speech and oral continence. Composite radial forearm flap with palmaris longus tendon is a good, reliable option for total lip reconstruction.


Asunto(s)
Colgajos Tisulares Libres , Labio/cirugía , Procedimientos de Cirugía Plástica/métodos , Anciano , Bangladesh , Antebrazo , Humanos , Neoplasias de los Labios/cirugía , Persona de Mediana Edad , Neoplasias de la Boca/cirugía , Tendones , Resultado del Tratamiento
10.
Autism Res ; 13(2): 284-297, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31647184

RESUMEN

This cross-sectional study examined the burden of depression and quality of life (QoL) among mothers of children with autism spectrum disorder (ASD) attending six schools offering special educational services for children with ASD in urban Dhaka, Bangladesh. All consenting mothers were 18 years of age and older and met criteria for major depressive disorder (MDD) on the Structured Interview for DSM-V-TR Research Version-non patient edition administered by trained raters. QoL was assessed by the EuroQol five-dimensional standardized questionnaire. MDD was diagnosed in 45% of mothers and was proportionally higher among those who did not work outside the home, had no childcare support at home, expressed low level of satisfaction with the quality of providers when they had sought care for their children with ASD, and reported being recipient of negative attitudes from neighbors toward their children with ASD. QoL was negatively associated with MDD, mothers' illness, and low satisfaction with the health care providers for children with ASD, as well as experiencing a negative attitude by neighbors toward their children. QoL was positively associated with the reported family monthly income and improvement of the children with ASD on school attendance. The prevalence of MDD among mothers of children with ASD was high and associated with poor QoL. Integrating mental health services and supports for mothers in the ASD care of children is likely to address the high burden of depression they face, and improve their overall quality of life. Autism Res 2020, 13: 284-297. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: The levels of depression were assessed among mothers of children with autism spectrum disorder (ASD) attending six schools offering special educational services for children with ASD in urban Dhaka, Bangladesh. Almost one in two mothers was found to have major depression. The quality of life of these mothers was generally poor. Integrating mental health services for mothers with ASD care in children is likely to address the burden of depression among the mothers of children with ASD and improve overall quality of life.


Asunto(s)
Trastorno del Espectro Autista/psicología , Costo de Enfermedad , Trastorno Depresivo Mayor/psicología , Madres/psicología , Calidad de Vida/psicología , Población Urbana/estadística & datos numéricos , Adulto , Bangladesh , Niño , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia
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