•This review work provides an up-to date information regarding the nanocellulose production from biomass by mechanical process.•A special focus is devoted to the pretreatment of lignocellulosic ...biomass for less energy consumption.•Application of nanocellulose-based materials for high performance nanobiocomposites and nanopaper technology are presented and discussed.•Chronology, challenges and obstacles of nanocellulose are discussed.
Nanofibrillated cellulose from biomass has recently gained attention owing to their biodegradable nature, low density, high mechanical properties, economic value and renewability. Although they still suffer from two major drawbacks. The first challenge is the exploration of raw materials and its application in nanocomposites production. Second one is high energy consumption regarding the mechanical fibrillation. However, pretreatments before mechanical isolation can overcome this problem. Hydrophilic nature of nano-size cellulose fibers restricts good dispersion of these materials in hydrophobic polymers and therefore, leads to lower mechanical properties. Surface modification before or after mechanical defibrillation could be a solution for this problem. Additionally, drying affects the size of nanofibers and its properties which needs to study further. This review focuses on recent developments in pretreatments, nanofibrillated cellulose production and its application in nanopaper applications, coating additives, security papers, food packaging, and surface modifications and also for first time its drying.
Healthcare waste comprises the waste generated by healthcare facilities, medical laboratories and biomedical research facilities. Improper treatment of this waste poses serious risks of disease ...transmission to waste pickers, waste workers, health workers, patients, and the community in general through exposure to infectious agents. Poor management of the waste emits harmful and deleterious contaminants into society. However, contamination of highly contagious agents such as the COVID-19 virus has created enormous instability in healthcare waste handling and subsequent recycling because of the volume of the waste generated and its contagious nature. Several countries have adopted safety measures to combat this contamination and manage healthcare waste; however, these measures are insufficient and vary depending on the context of the country. In addition, the WHO has set out guidelines for management of healthcare waste. These guidelines are helping to manage the highly contagious healthcare waste resulting from the current pandemic. Proper healthcare waste management may add value by reducing the spread of the COVID-19 virus and increasing the recyclability of materials instead of sending them to landfill. Disinfecting and sorting out healthcare waste facilitates sustainable management and allows their utilization for valuable purposes. This review discusses the different healthcare solid waste management strategies practiced in different countries, the challenges faced during this management, and the possible solutions for overcoming these challenges. It also provides useful insights into healthcare solid waste management scenarios during the COVID-19 pandemic and a possible way forward.
Display omitted
•Healthcare wastes have increased tremendously during COVID-19 pandemic.•Improper management of healthcare waste aids in transmission of COVID-19 virus.•Safety measures of waste workers and sanitization are pivotal for management.•On-site treatment and temporary storage reduce the burden of healthcare wastes.•Proper management practices alleviate landfill issues and further spread of virus.
Classified as a pandemic by the World Health Organization, the novel Coronavirus Disease (COVID-19) has spread to Bangladesh since early March of 2020, and people are getting daily updates from the ...social and electronic media. We aimed at assessing the prevalence of anxiety among Bangladeshi people during the pandemic in connection with social media exposure (SME) and electronic media exposure (EME). For this cross-sectional study, data were collected from 880 participants by a self-administered online-based questionnaire relating personal characteristics, self-rate health (SRH), SME, and EME with anxiety. Findings show that around half of the surveyed population experienced a spike of anxiety (49.1%) during the pandemic, ten times higher than the national anxiety rate in 2019. The participants with an increased SME of over four hours per day experienced a higher level of anxiety than individuals with < = 2 hours exposure to social media. Similarly, the anxiety was higher among people with fair/bad SRH compared to individuals with excellent SRH. It is highly recommended to develop active surveillance and effective monitoring systems to reduce the spread of misinformation from both social and electronic media to improve the state of mental health conditions during the pandemic.
•Tannins are important natural bioactive compounds found them in different forms.•Tannins are categorized into two types, i.e., condensed and hydrolyzable tannins; the sources of tannins are mainly ...barks, leaves, seeds and stems. However, tannins are also available in foodstuffs, i.e., tea, grape etc.•Condensed tannins are the most dominant one in the world market.•Wide range of solvents, i.e., water, methanol, ethanol, acetone and ionic liquids, and technologies, i.e., water, pressurized hot water, gamma assisted, infrared assisted and ultrasonic extraction are used for extracting tannins.•Tannins have many different applications largely in tanning industry, but they have some other advanced applications, such as, 3D printing, food supplement, medicines.
Tannins are found in most of the species throughout the plant kingdom, where their functions are to protect the plant against predation and might help in regulating the plant growth. There are two major groups of tannins, i.e., hydrolyzable and condensed tannins. The tannins are being used as important and effective chemicals for the tanning of animal hides in the leather processing industry since the beginning of the industry. Additionally, the tannins have been using as mineral absorption and protein precipitation purposes since 1960s. These are also used for iron gall ink production, adhesive production in wood-based industry, anti-corrosive chemical production, uranium recovering chemical from seawater, and removal of mercury and methylmercury from solution. Presently, tannins are considering as bioactive compound in nutrition science. It has also been considered for advanced applications, i.e., 3D printing and biomedical devices. The application of tannins as medicine is another new dimension in medical science. This paper outlines the general information about tannins followed by their extraction process. The utilization of tannins has also been presented in a broader scale. Depending on all these information, the article also describes the impending utilization of tannins for ensuring high-sustainability and better environmental performance.
•New adsorbents were prepared by combining chitosan and poly(1-vinylimidazole) using a facile technique.•High adsorption capacity was observed with the new adsorbent.•Synergistic effect was realized ...from chitosan and poly(1-vinylimidazole).•Interaction mechanism was also evaluated.
Chitosan and poly(1-vinylimidazole) are both potential adsorbents to remove Cr(VI). Here, we designed the preparation of new adsorbents by combining chitosan and poly(1-vinylimidazole) to get the synergistic effect for the removal of hexavalent chromium. Trimethoxysilyl group terminated poly(1-vinylimidazole)-modified-chitosan composite was successfully synthesized by one-step free radical polymerization based on the grafting backbone of chitosan and vinylimidazole. The resulting adsorbents were used for the removal of Cr(VI) ions from the aqueous solution. The modified chitosan composite was characterized by ATR, FTIR, BET isotherm studies, elemental analysis, TGA, DSC, FE-SEM, and EDX. ATR. FTIR results confirmed the presence of the imidazole group in modified chitosan. The adsorption results were described by the Langmuir isotherm model with a maximum adsorption capacity of 196.1 mg/g for modified chitosan, however, the chitosan yielded 151.5 mg/g. It has been observed that the adsorption of chromium fitted better with the pseudo-second-order kinetics. The modified chitosan composite exhibited greater adsorption capacity than chitosan for hexavalent chromium and has potential application for Cr(VI) removal from aqueous solution containing other common ions with regeneration ability. This novel approach of modifying chitosan with telomerized poly(1-vinyl imidazole) offers potential application in wastewater treatment of different industries releasing Cr (VI).
Groundwater recharge is affected by various anthropogenic activities, land use and land cover (LULC) change among these. The long-term temporal and seasonal changes in LULC have a substantial ...influence on groundwater flow dynamics. Therefore, assessment of the impacts of LULC changes on recharge is necessary for the sustainable management of groundwater resources. The objective of this study is to examine the effects of LULC changes on groundwater recharge in the northwestern part of Bangladesh. Spatially distributed monthly groundwater recharge was simulated using a semi-physically based water balance model. Long-term temporal LULC change analysis was conducted using LULC maps from 2006 to 2016, while wet and dry LULC maps were used to examine seasonal changes. The results show that the impervious built-up area has increased by 80.3%, whereas vegetated land cover has decreased by 16.4% over the study period. As a result, groundwater recharge in 2016 has decreased compared to the level seen in 2006. However, the decrease in recharge due to long-term temporal LULC changes is very small at the basin scale (2.6 mm/year), although the impact on regional level is larger (17.1 mm/year) due to urbanization. Seasonal LULC variations also affect recharge due to the higher potential for dry seasonal LULC compared to the wet seasonal LULC, a substantial difference (20.6 mm/year). The results reveal important information about the groundwater system and its response to land cover changes in northwestern Bangladesh.
•The effect of LULC changes on groundwater recharge is evaluated using a spatially distributed water balance model.•Impervious built-up area has increased by 80.3%, whereas vegetated land cover has decreased by 16.4% over the study period.•The decrease in recharge due to long-term temporal LULC changes is very small at the basin scale (2.6 mm/year).•The impact of LULC changes on groundwater recharge at the regional level is larger (17.1 mm/year) due to urbanization.•The seasonal changes in LULC have a substantial influence on groundwater recharge.
Knowing the risk factors like smoking status, overweight/obesity, and hypertension among women of reproductive age could allow the development of an effective strategy for reducing the burden of ...non-noncommunicable diseases. We sought to determine the prevalence and determinants of smoking status, overweight/obesity, hypertension, and cluster of these non-noncommunicable diseases risk factors among Bangladeshi women of reproductive age.
This study utilized the Bangladesh Demographic and Health Survey (BDHS) data from 2017-2018 and analyzed 5,624 women of reproductive age (age 18-49 years). This nationally representative cross-sectional survey utilized a stratified, two-stage sample of households. Poisson regression models with robust error variance were fitted to find the adjusted prevalence ratio (APR) for smoking, overweight/obesity, hypertension, and for the clustering of non-noncommunicable diseases risk factors across demographic variables.
The average age of 5,624 participants was 31 years (SD = 9.1). The prevalence of smoking, overweight/obesity, and hypertension was 9.6%, 31.6%, and 20.3%, respectively. More than one-third of the participants (34.6%) had one non-noncommunicable diseases risk factor, and 12.5% of participants had two non-noncommunicable diseases risk factors. Age, education, wealth index, and geographic location were significantly associated with smoking status, overweight/obesity, and hypertension. Women between 40-49 years had more non-noncommunicable diseases risk factors than 18-29 years aged women (APR: 2.44; 95% CI: 2.22-2.68). Women with no education (APR: 1.15; 95% CI: 1.00-1.33), married (APR: 2.32; 95% CI: 1.78-3.04), and widowed/divorced (APR: 2.14; 95% CI: 1.59-2.89) were more likely to experience multiple non-noncommunicable diseases risk factors. Individuals in the Barishal division, a coastal region (APR: 1.44; 95% CI: 1.28-1.63) were living with a higher number of risk factors for non-noncommunicable diseases than those in the Dhaka division, the capital of the country. Women who belonged to the richest wealth quintile (APR: 1.82; 95% CI: 1.60-2.07) were more likely to have the risk factors of non-noncommunicable diseases.
The study showed that non-noncommunicable diseases risk factors are more prevalent among women from older age group, currently married and widowed/divorced group, and the wealthiest socio-economic group. Women with higher levels of education were more likely to engage in healthy behaviors and found to have less non-noncommunicable diseases risk factors. Overall, the prevalence and determinants of non-noncommunicable diseases risk factors among reproductive women in Bangladesh highlight the need for targeted public health interventions to increase opportunities for physical activity and reduce the use of tobacco, especially the need for immediate interventions in the coastal region.
Healthy life expectancy (HALE) at birth is an important indicator of health status and quality of life of a country's population. However, little is known about the determinants of HALE as yet ...globally or even country-specific level. Thus, we examined the factors that are associated with HALE at birth in low- and lower-middle-income countries.
In accordance with the World Bank (WB) classification seventy-nine low- and lower-middle-income countries were selected for the study. Data on HALE, demographic, socioeconomic, social structural, health, and environmental factors from several reliable sources, such as the World Health Organization, the United Nations Development Program, Population Reference Bureau, WB, Heritage Foundation, Transparency International, Freedom House, and International Center for Prison Studies were obtained as selected countries. Descriptive statistics, correlation analysis, and regression analysis were performed to reach the research objectives.
The lowest and highest HALE were observed in Sierra Leone (44.40 years) and in Sri Lanka (67.00 years), respectively. The mean years of schooling, total fertility rate (TFR), physician density, gross national income per capita, health expenditure, economic freedom, carbon dioxide emission rate, freedom of the press, corruption perceptions index, prison population rate, and achieving a level of health-related millennium development goals (MDGs) were revealed as the correlates of HALE. Among all the correlates, the mean years of schooling, TFR, freedom of the press, and achieving a level of health-related MDGs were found to be the most influential factors.
To increase the HALE in low- and lower-middle-income countries, we suggest that TFR is to be reduced as well as to increase the mean years of schooling, freedom of the press, and the achievement of a level of health-related MDGs.
The recent outbreak of viral zoonotic disease-monkeypox-caused by the monkeypox virus, has infected many people worldwide. This study aims to explore the knowledge, attitudes, and practices (KAP) ...concerning monkeypox among university students in Bangladesh. Data were collected using purposive snowball sampling from 887 university students through an online survey using Google Form. The participants were mostly in their twenties (M = 22.33 SD 2.01 years), and they spent, on average, 2.59 SD 1.91 hours/day on electronic and social media. The participants generally showed moderate knowledge (39.5%), low attitude (25.1%), and moderate practice (48.6%) toward monkeypox, with 47.6% having had a moderate KAP score. Findings further showed that personal attributes of university students, i.e., age, sex, year of schooling, residence, living status, geographical distribution, e.g., division, were statistically and significantly associated with knowledge, attitudes, and practices regarding monkeypox and overall KAP score. It is also apparent that health status, susceptibility to monkeypox, and exposure to social media were the most common factors significantly associated with knowledge, attitudes, and practices regarding monkeypox and overall KAP score. The current study's findings underscore the need for developing appropriate information, education, and communication (IEC) materials and their dissemination, which could play an important role in reducing the risk of monkeypox and similar other infectious diseases, particularly among students in Bangladesh.
The carbon storage in Bangladeshi mangrove plantations is influenced by site-specific variations and plantation management practices. This study was focused on evaluating the impact of stand age and ...above-ground factors on the carbon storage of the western-side high-saline mangrove plantations in Bangladesh. A comprehensive field study was conducted, encompassing mangrove plantations aged 3, 5, 7, 10, 12, 15, and 35 years, to assess their potential for ecosystem carbon storage. The biomass data was calculated by estimating the tree height and diameter at breast height (DBH) with common allometric equations and soil samples were collected from every plot for estimating the organic carbon in the soil of the mangrove plantations. Stand structure attributes showed significant differences among all age classes and Sonneratia apetala was found to be dominant among all other species (IV = 147.41). Biomass C storage upsurges with age, ranging from 51.5±3.2–259.9±103.5 Mg C ha−1, while soil C storage averages 33.1±3.1 Mg C ha−1, showing no significant variation on age. Ecosystem carbon storage increases significantly with age and 35-year-old mangrove plantations exhibit the highest storage potential (292.0±105.5 Mg C ha−1). An analysis of species composition highlighted that Sonneratia apetala accumulated 94.1±28.4 Mg C ha−1 of biomass carbon, a figure notably higher than other species. The comparison indicated that, while the ecosystem carbon storage in Bangladesh is higher in mature-aged mangrove plantations, it lags behind young-aged mangrove plantations in Myanmar. Bangladesh exhibits a higher biomass carbon accumulation rate than China and India but falls short by 56% when compared to Myanmar's biomass carbon accumulation. However, these insights from mangrove plantation studies can serve as valuable guidance for policymakers and researchers, aiding in the conservation and management of mangroves and developing a blue carbon framework to meet the required funding for sustainable development of mangrove plantations and local communities in Bangladesh.
•Biomass C storage upsurges with age, ranging from 51.5∼259.9 Mg C ha-1.•Soil C storage showed no significant difference, with a mean of 33.1±3.1 Mg C ha-1.•The ecosystem carbon increases over age but sequestration decreases.•C storage potential of Bangladesh is comparable with other mangrove plantations.
PDF
