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1.
Heliyon ; 10(9): e30369, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38720756

ABSTRACT

Introduction: During the COVID-19 pandemic, restrictions significantly impacted religious activities related to death celebrations, mortuary practices, and funerary rituals in Bangladesh. Bereaved families faced a harsh reality, unable to perform the full rituals for their loved ones due to the pandemic outbreak. This study explores the adjustments and modifications made in cultural rituals and how they affected bereaved families and close relatives. Objective: This study aims to explore how the COVID-19 pandemic impacted the observance of death rituals in Bangladesh and the effects on bereaved families and close relatives. Methods: This study employed a qualitative approach and gathered data through 3 key informant interviews (KIIs) and 58 in-depth interviews (IDIs) conducted between December 2020 and January 2021. Purposive sampling was employed to recruit participants from three distinct groups: (1) individuals who had experienced the death of a relative during the pandemic, (2) caregivers who provided support to those experiencing loss, and (3) volunteers actively involved with funeral and burial services. This selection strategy ensured a diverse range of perspectives on the impact of the pandemic on death rituals. Results: The pandemic forced people to observe funerals or make significant sacrifices to traditional practices reluctantly. Disruptions to long-standing traditions and widespread emotional toll were as various segments of society struggled to find closure in saying goodbye to loved ones. Due to the severity of the pandemic, people became heavily reliant on priests, crematorium workers, and funeral volunteers for mortuary services. Both Hindu and Muslim religions discouraged family gatherings during post-burial rituals. The fear of contracting the virus further limited bereaved families' ability to bid farewell to their deceased loved ones properly. Conclusion: This research highlights the profound impact of the pandemic on death rituals and the resulting emotional distress for bereaved families in Bangladesh. The findings are pivotal in guiding the development of concrete policies for future pandemic preparedness and response. Such policies might encompass guidelines for safe and culturally sensitive mortuary practices, psychosocial support and grief counseling initiatives for affected communities, and strategies to mitigate religious anxieties during public health emergencies.

2.
Heliyon ; 10(10): e31534, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38818141

ABSTRACT

Composites are new materials that combine two or more distinct components with diverse properties to create a new material with improved properties. The goal of this endeavor was to use fiber preparation wastes, or waste from cotton spinning mill blow room and carding, to produce bio composites based on starch. The matrix was prepared using the starches of potatoes, maize, and arrowroot, and any remaining reinforcing material was used. A hand layup technique was used to make the bio-composites. Tensile, bending, density, water absorbency, and SEM testing were among the studies used to illustrate the starch-based biodegradable materials. The maximum tensile strength of 0.49 MPa is displayed by sample AB. The resistive bending force of 3.71 MPa is greatest in Sample AB. The most uniform combination of reinforcing material (wastage cotton) and matrix is seen in PB's SEM picture. Among the samples, AB had the greatest density value, measuring 0.35 g/cm3. The sample PC had the highest absorption findings in both water and the 5 % HCl combination because carding waste had more fiber than blow room and fiber absorbs more water. The resultant bio-composites made of starch had the potential to replace Styrofoam.

3.
Heliyon ; 10(2): e25027, 2024 Jan 30.
Article in English | MEDLINE | ID: mdl-38312702

ABSTRACT

The present world is focusing on sustainable products. Most of the natural products collected from are environmentally friendly. In the textile sector the main raw material is fiber. Most textile products are made from the natural cotton fibers. But because of the shortage of this fiber, most of the researchers are looking forwards to other sources of natural fibers. Here in Bangladesh the natural jute fiber is available and the textile industries are making jute products but the jute products are comparatively lower price than cotton products. That's why some factories are making cotton-jute blended yarn to minimise the cost and increase the product's quality and appearance. Here in this research work, it was tried to identify the best cotton-jute blended ratio for producing good quality yarn. 80C-20 J, 60C-40 J and 40C-60 J blended ratios are compared with 100 C and 100 J yarn to analyse the results. The CV m%, Thick/Km +50 %, Neps/Km +200 %, IPI, RKM and Elongation% of blended yarns are evaluated and compared the results between the ratios. After that the yarn quality index (YQI) was calculated to identify the ratio which indicates a relation between yarns strength, elongation% and CVm. The other quality index was fiber quality index (FQI) which indicates a relation between fibers strength, fiber mean length, elongation% and fiber fineness. One way ANOVA was applied to see the significance level between the independent variables. Box plot was applied to see the visual effect of statistical analysis at the same time the regression results show the impact of cotton-jute ratio with an equation, through which it was easy to identify the perfect ratio. It was found that higher percentage of cotton and lower percentage of jute fiber blended yarn shows good results than others. The products which were made from the ratios were shown good results for their different use of purposes.

4.
Environ Res ; 250: 118436, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38354890

ABSTRACT

Extreme weather events in South and Southeast Asia exert profound psychosocial impacts, amplifying the prevalence of mental illness. Despite their substantial consequences, there is a dearth of research and representation in the current literature. We conducted a systematic review of observational studies published between January 1, 2000, and January 20, 2024, to examine the impact of extreme weather events on the mental health of the South and Southeast Asian population. Quality assessment of the included studies was conducted using the Newcastle-Ottawa Scale (NOS) quality appraisal checklist. The search retrieved 70 studies that met the inclusion criteria and were included in our review. Most were from India (n = 22), and most used a cross-sectional study design (n = 55). Poor mental health outcomes were associated with six types of extreme weather events: floods, storm surges, typhoons, cyclones, extreme heat, and riverbank erosion. Most studies (n = 41) reported short-term outcome measurements. Findings included outcomes with predictable symptomatology, including post-traumatic stress disorder, depression, anxiety, general psychological distress, emotional distress and suicide. Limited studies on long-term effects showed higher mental disorders after floods and typhoons, while cyclone-exposed individuals had more short-term distress. Notably, the review identified over 50 risk factors influencing mental health outcomes, categorized into six classes: demographic, economic, health, disaster exposure, psychological, and community factors. However, the quantitative evidence linking extreme weather events to mental health was limited due to a lack of longitudinal data, lack of control groups, and the absence of objective exposure measurements. The review found some compelling evidence linking extreme weather events to adverse mental health in the South and Southeast Asia region. Future research should focus on longitudinal study design to identify the specific stressors and climatic factors influencing the relationship between climate extremes and mental health in this region.


Subject(s)
Extreme Weather , Mental Health , Humans , Mental Health/statistics & numerical data , Asia, Southeastern/epidemiology , Mental Disorders/epidemiology , Observational Studies as Topic
5.
Heliyon ; 9(9): e19360, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37662786

ABSTRACT

Riding on the journey of a sustainable world it is very crucial to extend the usage of natural cellulosic fiber from renewable sources. Due to their numerous applications and eco-friendly behavior, natural cellulosic fibers are in greater demand every day. In this article a new natural fiber extracted from the creepers of Mikania micrantha with the help of 5% NaOH retting process. Previously no research work have been done with this fiber. The fiber was characterized by following ASTM D1909, ASTM D 2654, ASTM D1445, TAPPI standard for determination of moisture regain and content, bundle fiber strength and chemical composition respectively. XRD, SEM, FTIR and TGA analysis were also done for the identification of crystallinity, fiber morphology, functional group and thermal behavior. The tests results showed that it is a cellulose enriched textile fiber having 56.42% cellulose. The average moisture regain and content % were 9.17% and 8.4% respectively analyzed from the five samples. The average tenacity was determined 38.6 gm/tex with 1.8% elongation and the crystallinity of the tested fiber was 72%. The maximum degradation temperature for this fiber was 477 °C. The application of this noble fiber can be for making fiber reinforced composites, cellulose nanomaterials, biomaterials etc.

6.
ACS Appl Mater Interfaces ; 15(35): 41606-41613, 2023 Sep 06.
Article in English | MEDLINE | ID: mdl-37610983

ABSTRACT

AlxSc1-xN is a nitride-ferroelectric compatible with both CMOS and GaN technology. The origin of ferroelectricity in these ternary nitrides relies on the full inversion of nitrogen atom positions, which is a significantly different structural mechanism than conventional perovskites. Therefore, its ferroelectric characteristics exhibit a high remanent polarization and a tunable coercive field but suffer heavily from leakage currents during the switching event. In this article, we studied epitaxially grown Al0.72Sc0.28N thin films on epitaxial Pt electrode layers deposited on GaN/Al2O3 substrates. The results are compared both structurally and electrically with similar systems on SiO2/Si substrates. Our X-ray diffraction analysis showed that Al0.72Sc0.28N/epi-Pt/GaN is always a complete epitaxial stack without any significant strain gradient. Electrically, this system has an overall lower leakage current and coercive field compared to directly grown, highly crystalline, strained epitaxial Al0.72Sc0.28N/GaN, despite having a lower crystalline quality of the ferroelectric layer. In addition, decreasing the epi-Pt thickness from 100 to 10 nm resulted in further improvement of the leakage profile, which we attribute to a decrease in surface roughness in the thinner Pt. In contrast, the dominant factor of leakage in a fiber-textured system on Si substrates is the Pt(111) texture. Finally, with the combination of in-plane X-ray diffraction and high-resolution scanning transmission electron microscopy, we have demonstrated an all-epitaxial 20 nm Al0.72Sc0.28N/Pt/GaN MFM stack with a sharp interface thickness of less than 1 nm.

7.
Adv Sci (Weinh) ; 10(25): e2302296, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37382398

ABSTRACT

Analog switching in ferroelectric devices promises neuromorphic computing with the highest energy efficiency if limited device scalability can be overcome. To contribute to a solution, one reports on the ferroelectric switching characteristics of sub-5 nm thin Al0.74 Sc0.26 N films grown on Pt/Ti/SiO2 /Si and epitaxial Pt/GaN/sapphire templates by sputter-deposition. In this context, the study focuses on the following major achievements compared to previously available wurtzite-type ferroelectrics: 1) Record low switching voltages down to 1 V are achieved, which is in a range that can be supplied by standard on-chip voltage sources. 2) Compared to the previously investigated deposition of ultrathin Al1-x Scx N films on epitaxial templates, a significantly larger coercive field (Ec ) to breakdown field ratio is observed for Al0.74 Sc0.26 N films grown on silicon substrates, the technologically most relevant substrate-type. 3) The formation of true ferroelectric domains in wurtzite-type materials is for the first time demonstrated on the atomic scale by scanning transmission electron microscopy (STEM) investigations of a sub-5 nm thin partially switched film. The direct observation of inversion domain boundaries (IDB) within single nm-sized grains supports the theory of a gradual domain-wall driven switching process in wurtzite-type ferroelectrics. Ultimately, this should enable the analog switching necessary for mimicking neuromorphic concepts also in highly scaled devices.

8.
Small ; 19(18): e2207492, 2023 May.
Article in English | MEDLINE | ID: mdl-36782364

ABSTRACT

The material design of functional "aero"-networks offers a facile approach to optical, catalytical, or and electrochemical applications based on multiscale morphologies, high large reactive area, and prominent material diversity. Here in this paper, the synthesis and structural characterization of a hybrid ß-Ga2 O3 /ZnGa2 O4 nanocomposite aero-network are presented. The nanocomposite networks are studied on multiscale with respect to their micro- and nanostructure by X-ray diffraction (XRD) and transmission electron microscopy (TEM) and are characterized for their photoluminescent response to UV light excitation and their electrochemical performance with Li-ion conversion reaction. The structural investigations reveal the simultaneous transformation of the precursor aero-GaN(ZnO) network into hollow architectures composed of ß-Ga2 O3 and ZnGa2 O4 nanocrystals with a phase ratio of ≈1:2. The photoluminescence of hybrid aero-ß-Ga2 O3 /ZnGa2 O4 nanocomposite networks demonstrates narrow band (λem  = 504 nm) green light emission of ZnGa2 O4 under UV light excitation (λex  = 300 nm). The evaluation of the metal-oxide network performance for electrochemical application for Li-ion batteries shows high initial capacities of ≈714 mAh g-1 at 100 mA g-1 paired with exceptional rate performance even at high current densities of 4 A g-1 with 347 mAh g-1 . This study provides is an exciting showcase example of novel networked materials and demonstrates the opportunities of tailored micro-/nanostructures for diverse applications a diversity of possible applications.

9.
ACS Appl Mater Interfaces ; 15(5): 7030-7043, 2023 Feb 08.
Article in English | MEDLINE | ID: mdl-36715613

ABSTRACT

The discovery of ferroelectricity in aluminum scandium nitride (Al1-xScxN) opens technological perspectives for harsh environments and space-related memory applications, considering the high-temperature stability of piezoelectricity in aluminum nitride. The ferroelectric and material properties of 100 nm-thick Al0.72Sc0.28N are studied up to 873 K, combining both electrical and in situ X-ray diffraction measurements as well as transmission electron microscopy and energy-dispersive X-ray spectroscopy. The present work demonstrates that Al0.72Sc0.28N can achieve high switching polarization and tunable coercive fields in a 375 K temperature range from room temperature up to 673 K. The degradation of the ferroelectric properties in the capacitors is observed above this temperature. Reduction of the effective top electrode area and consequent oxidation of the Al0.72Sc0.28N film are mainly responsible for this degradation. A slight variation of the Sc concentration is quantified across grain boundaries, even though its impact on the ferroelectric properties cannot be isolated from those brought by the top electrode deterioration and Al0.72Sc0.28N oxidation. The Curie temperature of Al0.72Sc0.28N is confirmed to be above 873 K, thus corroborating the promising thermal stability of this ferroelectric material. The present results further support the future adoption of Al1-xScxN in memory technologies for harsh environments like applications in space missions.

10.
F1000Res ; 12: 1364, 2023.
Article in English | MEDLINE | ID: mdl-38826573

ABSTRACT

Background: Children globally, including in Bangladesh, are facing various forms of online sexual abuse including sextortion, exploitation, body shaming, and blackmail. They are also coerced into engaging in intimate activities, harassed through the sending of sexual content, among other forms of abuse. We aimed to explore the root cause of online child sexual abuse (OCSA) in Bangladesh. Methods: This qualitative research design utilized in-depth interviews (IDIs) and key informant interviews (KIIs) between February and April 2022. The study sample comprised 21 school-going children aged 13-17 years, selected from two different geographical settings (10 from rural areas and 11 from urban areas) in Bangladesh using purposive sampling techniques. They participated in in-depth interviews (IDIs) while additional data was obtained through key informant interviews (KIIs) with 11 multidisciplinary stakeholders. Results: Children from both rural and urban areas reported facing abuse in various ways, such as being asked to send naked photos, being invited to be naked in video calls, and being invited to have virtual sex, among others, over the internet. Conclusions: The government should consider integrating OCSA education into secondary levels. Additionally, there should be efforts to ensure a safe online environment through content scrutiny, promotion of outdoor activities, and community campaigns. An anonymous reporting system must be implemented, and strict measures under the Children's Act must be enforced against perpetrators. Further intervention studies are needed to ensure effective child protection measures in Bangladesh.


Subject(s)
Child Abuse, Sexual , Qualitative Research , Humans , Bangladesh/epidemiology , Adolescent , Female , Male , Child Abuse, Sexual/statistics & numerical data , Internet , Rural Population , Child , Urban Population
11.
Micromachines (Basel) ; 13(8)2022 Aug 08.
Article in English | MEDLINE | ID: mdl-36014204

ABSTRACT

Ferroelectric thin films of wurtzite-type aluminum scandium nitride (Al1−xScxN) are promising candidates for non-volatile memory applications and high-temperature sensors due to their outstanding functional and thermal stability exceeding most other ferroelectric thin film materials. In this work, the thermal expansion along with the temperature stability and its interrelated effects have been investigated for Al1−xScxN thin films on sapphire Al2O3(0001) with Sc concentrations x (x = 0, 0.09, 0.23, 0.32, 0.40) using in situ X-ray diffraction analyses up to 1100 °C. The selected Al1−xScxN thin films were grown with epitaxial and fiber textured microstructures of high crystal quality, dependent on the choice of growth template, e.g., epitaxial on Al2O3(0001) and fiber texture on Mo(110)/AlN(0001)/Si(100). The presented studies expose an anomalous regime of thermal expansion at high temperatures >~600 °C, which is described as an isotropic expansion of a and c lattice parameters during annealing. The collected high-temperature data suggest differentiation of the observed thermal expansion behavior into defect-coupled intrinsic and oxygen-impurity-coupled extrinsic contributions. In our hypothesis, intrinsic effects are denoted to the thermal activation, migration and curing of defect structures in the material, whereas extrinsic effects describe the interaction of available oxygen species with these activated defect structures. Their interaction is the dominant process at high temperatures >800 °C resulting in the stabilization of larger modifications of the unit cell parameters than under exclusion of oxygen. The described phenomena are relevant for manufacturing and operation of new Al1−xScxN-based devices, e.g., in the fields of high-temperature resistant memory or power electronic applications.

12.
Micromachines (Basel) ; 13(5)2022 May 17.
Article in English | MEDLINE | ID: mdl-35630250

ABSTRACT

In this work, we present a method for growing highly c-axis oriented aluminum scandium nitride (AlScN) thin films on (100) silicon (Si), silicon dioxide (SiO2) and epitaxial polysilicon (poly-Si) substrates using a substrate independent approach. The presented method offers great advantages in applications such as piezoelectric thin-film-based surface acoustic wave devices where a metallic seed layer cannot be used. The approach relies on a thin AlN layer to establish a wurtzite nucleation layer for the growth of w-AlScN films. Both AlScN thin film and seed layer AlN are prepared by DC reactive magnetron sputtering process where a Sc concentration of 27% is used throughout this study. The crystal quality of (0002) orientation of Al0.73Sc0.27N films on all three substrates is significantly improved by introducing a 20 nm AlN seed layer. Although AlN has a smaller capacitance than AlScN, limiting the charge stored on the electrode plates, the combined piezoelectric coefficient d33,f with 500 nm AlScN is only slightly reduced by about 4.5% in the presence of the seed layer.

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