University of Chittagong

Traditional paddy cultivars (TPC) have a high nutritional and medicinal value and can survive severe stress conditions. TPCs are soil and region-specific, produced with organic manure, and free of pesticides or insecticides; as a result, they are more resistant to pests and naturally strong. TPCs are the best solution to the issues of unpredictable rainfall and aid in preventing pest infection since climate change does not affect them, such as increases or decreases in temperatures, humidity, and drought. TPCs are more valuable on the market than new high-yielding and improved varieties and need less labour to grow. Traditional rice has been used to treat various specific conditions, including high blood pressure, digestive system issues, skin inflammation, and blood sugar regulation. This review aims to educate farmers, seed growers, and researchers receiving valuable information regarding the importance of different TPC and cultivating more areas of suitable traditional cultivars of paddy for sustainable agriculture. Therefore, it is crucial to put policies in place to properly preserve farmers' variety if agriculture is to thrive sustainably.

Water quality monitoring in shallow and sheltered sub-tropical coastal water bodies like the Mississippi Sound is crucial for understanding ecosystem dynamics and supporting management decisions, especially when considering major river diversion projects. Application of machine learning (ML) techniques offers promising cost-effective new approaches utilizing archived remote sensing data for analyzing complex environmental data and predicting water quality parameters accurately and efficiently. The aim of this research was to leverage Landsat satellite imagery and ocean optics data from Aqua MODIS in conjunction with ML techniques to enhance the accuracy and efficiency of chlorophyll-a (Chla) estimation in the Mississippi Sound with a focus on variability driven by seasonal patterns, riverine inputs, and ocean biogeochemical parameters. Using a robust ML model based on an ensemble model, Extra Trees (ET), we estimated Chla concentrations across twelve months and evaluated the model’s performance against other ML regression-based models. The ET model consistently provided accurate and reliable predictions, achieving an R² of 0.999 and a root mean square error of 0.187 mg/m³. By capturing complex interactions influencing Chla variability, the ET model demonstrated superior performance compared to traditional empirical and regression-based methods. Model outputs showing lower Chla concentrations observed during winter months align with established seasonal trends in temperate coastal ecosystems. Conversely, the higher Chla concentrations observed along the coast are attributed to increased nutrient inputs from rivers such as the Pearl, Pascagoula, and Mobile Rivers, as well as coastal runoff and freshwater diversions from the Mississippi River. The influx of freshwater increased levels of nutrients, total suspended solids, phytoplankton, and total organic carbon, which resulted in higher light extinction and diminished light penetration to the seabed. This research improves our comprehension of Chla fluctuations in the Mississippi Sound and showcases the promise of cutting-edge machine learning methods for monitoring and forecasting coastal ecosystems.

The microstrip patch antenna was specifically designed to be operational at a frequency of 7.8 GHz for applications in WiMAX and X-band satellite communication. The proposed design utilized a patch with optimized dimensions on Rogers RT/duroid substrate with a permittivity of 2.2 and a thickness of 1.5 mm. The patch of the antenna comprised two patch elements that were connected to each other. Adding the second patch enhanced the antenna's performance by improving its return loss to -49.92 dB and VSWR to 1.006 along with achieving an optimal gain of 8.5 dB. The antenna demonstrated a resonant frequency of 7.8 GHz with a stable radiation pattern, low return loss (-49.92 dB), low VSWR, and high gain of about 8.5 dB.

This paper presents the development and analysis of a high-performance, optimized multiband, two-port Multiple-Input-Multiple-Output (MIMO) antenna with a dimension of 2.0517λ × 1.1737λ × 0.0132λ μm3, which is further extended up to a four-port antenna. The antenna design incorporates graphene, with a thickness of 0.34 nm in the patch and ground plane. It utilizes polyimide (ϵr = 3.5) as a substrate with a unique slot-loaded patch while also providing a thorough examination of their performance over five different substrate materials (Polyimide, Quartz, SiO2, Epoxy Regin, and Rogers RT6006). Initially, a basic patch antenna was built, then by incorporating various slots in the patch element the overall performance of the antenna was optimized. After that, an inverted L-shaped stub was integrated into the partial ground, and it was transformed into a 2-port parallel MIMO antenna. To enhance the performance further the antenna elements were positioned in an orthogonal arrangement. Furthermore, with the addition of metamaterial-inspired (MTM-inspired) shapes in between the antenna elements increase the level of isolation of about −90 dB. Finally, a corresponding four-port antenna was built and its performance characteristics were studied and compared with the two-port counterpart. The proposed two-port MIMO antenna demonstrates an exceptional reflection coefficient of −59 dB, accompanied by remarkable isolation of −90 dB, along with a gain of around 12.48 dBi. Moreover, crucial MIMO antenna performance metrices including Diversity Gain, Mean Effective Gain, Envelope Correlation Coefficient, Total Active Reflection Coefficient, and Channel Capacity Loss were also investigated to substantiate the proposed design. A thorough investigation of the proposed work in compared to the existing literature has been carried out, explicitly demonstrating the superiority of the proposed design. Overall simulation has been carried out using the CST Microwave Studio Suite.

Noncanonical autophagy including unconventional protein secretion has been extensively studied. Our work focused on a leaderless IL-1β protein secretion from human macrophage in response to Acanthamoeba castellanii components, Acanthamoeba culture supernatant (CS) and cell lysate (CL), as well as its association with macrophage autophagy. Phorbol 12-myristate 13-acetate (PMA)–induced THP-1 macrophages were treated with Acanthamoeba components of pathogenic (ATCC50739) and nonpathogenic (ATCC30010) strains in vitro. The data showed that Acanthamoeba treatment resulted in low IL-1β secretion from macrophages. In addition, Acanthamoeba CL of both strains was able to upregulate autophagy-related (Atg) protein 8, an autophagy marker, whereas Acanthamoeba CS downregulated Atg8 expression. We further manipulated autophagy and found that autophagy induction by starvation diminished IL-1β secretion while autophagy inhibition by 3-methyladenine (3MA) increased IL-1β secretion. Interestingly, in the presence of Acanthamoeba components either under starvation or 3MA treatment, IL-1β secretion was significantly reduced. Transcriptional expression of other ATG genes, i.e., ATG6, ATG7, and ATG5, were investigated and showed that their mRNA expression was maintained at the basal level under A. castellanii CS or CL treatment. Inflammasome-related genes, NLRP3 and CASPASE1, were upregulated following A. castellanii 50739 CS treatment but not in A. castellanii 50739 CL-treated condition. However, both conditions were able to increase IL-1β mRNA expression. TEM micrographs revealed that 3MA treatment induced the formation of large vacuoles and accumulation of autophagosome at the edge of THP-1 macrophages. However, the number and size of their structures were declined in the presence of A. castellanii 50739 CS with 3MA. Furthermore, immunofluorescence staining demonstrated the association between Atg8/LC3 and IL-1β expression, where downregulation of Atg8 by A. castellanii 50739 CS led to the upregulation of IL-1β. Altogether, the data indicate that Acanthamoeba can manipulate macrophage autophagy, thereby controlling low IL-1β secretion. The expression of autophagy- and inflammasome-related genes also indicates multiple mechanisms in IL-1β secretion in response to Acanthamoeba components. However, further characterization of Atg proteins and investigations into other intracellular pathways or defense mechanisms are needed to fully understand the unconventional secretion of IL-1β in macrophages. This knowledge could eventually lead to the development of innovative therapeutic strategies against Acanthamoeba infection by modulating autophagy or macrophage responses.

Protonic ceramic fuel cells (PCFCs) should exhibit high performance at intermediate temperatures in the range of 400–600 °C. To reduce the operating temperature, more active air electrodes (positrodes) are needed. In the present work, BaCo0.4Fe0.4Mg0.1Y0.1O3-δ (BCFMY) is investigated as a positrode material for application in PCFCs as well as solid oxide fuel cells (SOFCs). For SOFCs, the polarization resistance ascribed to the oxygen reduction reaction is proportional to pO2−1/4 (pO2: oxygen partial pressure), suggesting that the rate-determining process is the charge transfer on the mixed ionic-electronic conductors. For PCFCs, this polarization resistance is proportional to pO2⁻1/2, suggesting that the rate-determining process is the oxygen dissociation. The total polarization resistance for the PCFCs using the BCFMY positrode is 0.066 Ωcm² at 600 °C, lower than that using the BaCo0.4Fe0.4Zr0.1Y0.1O3-δ (BCFZY) positrode. The higher oxygen nonstoichiometry of BCFMY promotes the oxygen dissociation process on the PCFC positrode surface.

We studied nongeographic intraspecific variation of craniofacial morphology in the lesser bandicoot rat ( Bandicota bengalensis ) by applying linear morphometric methods. Among 26 morphometric characteristics of 30 adult skulls (11 males and 19 females), males exhibited a slightly larger average size in 22 measurements, most of which were non-significant. Males were significantly larger than females only in short lateral facial length. Although, discriminant functions revealed large disparities between the sexes, leave-one-out cross-validation demonstrated that only 43.33% of specimens were properly classified into the sexes. K-means clustering indicated the correct assignment for 30% of specimens to their own clusters. The allometric slopes were also not significantly different between sexes. Therefore, common allometric trends were considered for subsequent investigation. Both bivariate regression (ordinary least-squares and reduced major axis) methods were consistent in allometric trends for most measurements and revealed distinct patterns of allometry in the major sub-regions of craniofacial morphology. In conclusion, we found a limited craniofacial sexual dimorphism in B. bengalensis with similar patterns of allometric growth.

Elatostema sessile is used by traditional medicinal practitioners to treat various diseases. The methanol extract (MES) and its fractions, including petroleum ether (PES), carbon tetrachloride (TES), chloroform (CES), and aqueous soluble fractions (AES), were tested for their antioxidant, cytotoxic, analgesic, and sedative properties on Swiss albino mice. In addition, we used GCMS to determine the bioactive compounds present in the MES of E. sessile. The MES had the lowest IC50 value (24.95 μg/mL) for antioxidant activity, measured by DPPH free radical scavenging, whereas the IC50 value for ascorbic acid was 5.80 μg/mL. In cytotoxic test with brine shrimp, PES exhibited the lowest LC50 value of 6.10 μg/mL among all the extract. Using the formalin‐induced paw licking method, MES and PES showed substantial results (p < 0.001) at 400 mg/kg dose. The tail immersion test showed significant (p < 0.05) findings for MES, PES, and TES after 30, 60, and 90 min following 400 mg/kg dose administration. The hole‐cross test demonstrated highly statistically significant results (p < 0.001) for the sedative activity of PES at a dose of 400 mg/kg after 30 min of administration and for CES after 90 min. According to molecular docking investigations, the extract has the potential to function as a pain‐relieving drug by inhibiting the enzymatic activity of cyclooxygenases 1 and 2. In summary, the results indicate that E. sessile offers significant therapeutic promise in the creation of innovative therapies for cancer, pain, and sleep problems.

Depression and anxiety are common mental health issues globally, yet limited research has focused on job seekers in Bangladesh. This study examines the prevalence and associated factors of depression and anxiety symptoms among Bangladeshi graduates seeking employment. A cross-sectional study was conducted among graduates from two public universities in Bangladesh, using face-to-face interviews and a semi-structured questionnaire. Data were collected between March and April 2024 through convenience sampling. Chi-square tests and logistic regression were used for analysis with SPSS software. Among the participants, 46.8% experienced depressive symptoms and 67.8% had anxiety symptoms, with 42.3% experiencing both. Factors associated with a reduced risk of depressive symptoms included being a first child (OR = 0.48, 95% CI: 0.25–0.93, p = 0.031) and exam satisfaction (OR = 0.22, 95% CI: 0.12–0.39, p < 0.001). Lower symptoms of anxiety were associated with being male (OR = 0.45, 95% CI: 0.25–0.80, p = 0.007), first-born status (OR = 0.45, 95% CI: 0.22–0.92, p = 0.030), financial contribution to family (OR = 0.40, 95% CI: 0.19–0.81, p = 0.011), over 12 months of preparation (OR = 0.37, 95% CI: 0.15–0.92, p = 0.034) and exam satisfaction (OR = 0.40, 95% CI: 0.22–0.71, p = 0.002). Intentionally unemployed participants had a higher risk of anxiety symptoms (OR = 1.70, 95% CI: 1.00–2.89, p = 0.046). This study reveals high rates of depressive and anxiety symptoms among job-seeking graduates in Bangladesh. Socio-demographic and job-related factors appear to significantly impact mental health, underscoring the need for a holistic approach to address these challenges. Targeted mental health interventions and increased public awareness are essential to support vulnerable groups in navigating the highly competitive job market.

Seaweeds, an important component of the Blue Economy of Bangladesh, have the potential to significantly increase both the national GDP and the standard of living in coastal communities. Seaweed with huge medical value and an excellent cuisine has exporting prospects as seafood to earn huge amounts of foreign cash. Moreover, the biochemical, medicinal, and cosmetics industries use seaweed as a component of different products. Many Southeast Asian nations have a highly developed seaweed industry (e.g., China, Indonesia, and the Philippines). An area of 47,201 km2, or 32% of the country, is made up of 19 districts in Bangladesh’s coastal region. The coastal environment, which includes muddy and sandy coastlines, estuaries, and mangrove areas, can provide an appropriate habitat for seaweed growth. Eight out of the 133 kinds of seaweed that are abundantly available in Bangladesh are commercially significant. Nowadays, seaweed production is being tried on Bangladesh’s coastline, and many government and non-government organizations are carrying out various seaweed culture/research programs. Some of the findings are good but not up to the mark. They are attempting to lessen the issues they are now encountering. Several strategies are being used to address the risk issues. For Bangladesh’s seaweed culture to be effective, ongoing study is required to improve the technologies for the production of various commercially significant seed stocks and their advancements. To find ideal locations for widespread seaweed cultivation, thorough surveys must also be carried out for the expansion of seaweed cultivation.

Antimicrobial resistance (AMR) in fish feed sources is becoming a major concern due to the potential spread of resistant microbes to humans through contaminated fish products. This jeopardizes the nutritional and economic viability of aquaculture systems, as it disrupts the efficacy of antimicrobials (AMs) and fosters the proliferation of antibiotic-resistant genes. The development and spread of AMR bacteria are influenced by several factors, such as the use of antibiotics in aquaculture, easy access to AMs, use of sub-therapeutic doses of AMs, discharge of effluents from aqua farms into the environment, inappropriate disposal of antibiotics, lack of awareness among farmers, and, to sum up, poor management practices. Therefore, it is important to establish proper screening and monitoring techniques to prevent the spread of AMR. This involves identifying the presence of AMR bacteria in feed samples, monitoring changes in the prevalence of AMR over time, and tracking the spread of AMR between different species. This insight enables us to improve feed production practices, guide the selection of alternative feed sources, and help mitigate the risk of AMR transmission. This chapter reviews the present knowledge on the types of feed sources, their potential for AMR transmission, and interspecies transmission pathways. Moreover, the chapter examines the different methods of screening and monitoring programs with possible challenges associated with their implementation.

Capsicum chinense (C. chinense) Jacq., recognized for its bioactive compounds, has attracted interest due to its possible immunomodulatory and DNA-damage-protective effects. This study aimed to assess the immunomodulatory, anti-inflammatory, and DNA protection abilities of organic extracts (methanol, ethyl acetate, and petroleum ether) from C. chinense. The immunomodulatory effects were evaluated in Long Evans rats induced with SRBC. At the same time, the anti-inflammatory potential was investigated in LPS-stimulated RAW264.7 macrophages by quantifying pro-inflammatory mediators such as COX-2, iNOS, TNF-α, IL-β, and IL-6. Protective activity against DNA damage was assessed using a method that induces damage with a Fenton reagent. Cytotoxicity was tested on the Hela cell line to gauge the cellular effects of the extracts. The results demonstrated that higher doses (200 mg) of C. chinense methanol extract inhibited immune responses, whereas lower doses helped restore them. The extracts significantly decreased pro-inflammatory mediators and cytokines in LPS-activated macrophages. Both petroleum ether and methanol extracts showed higher cytotoxicity against Hela cells compared to the ethyl acetate extract. The protein levels recorded in the serological parameters were 5.74 ± 0.19, 5.36 ± 0.11, 5.74 ± 0.26, 6.02 ± 0.16, 6.18 ± 0.18, and 6.22 ± 0.20 gm/dL for NC, DC, ML, MLMExCC100, MLMExCC200, and MExCC100, respectively. These findings suggest that C. chinense extracts possess strong immunomodulatory effects and potential protection against DNA damage, supporting their therapeutic application in regulating the innate immunity system.

Objectives A scale measuring students’ attention regulation in classroom contexts has not yet been developed. This research developed and validated the classroom mindful attention regulation scale (CMARS) using modern psychometric approaches for Bangladeshi emerging adults. Method A convenience sample of 600 university students aged 18–25 years was recruited. Measures completed by the participants include CMARS, Mindful Attention Awareness Scale, Philadelphia Mindfulness Scale, and Depression Anxiety Stress Scale-21. To examine the factor structure and ensure factor retention, an exploratory factor analysis (EFA) and parallel analysis (PA) were run, respectively. To validate the factor structure, confirmatory factor analysis (CFA) was performed. Cronbach’s alpha, McDonald’s omega, and Ferguson’s delta were used to determine the internal consistency reliabilities. Multi-group confirmatory factor analysis (MGCFA) was conducted to test the invariance across gender. Results Content validation resulted in the retention of 10 items. The two-factor structure emerged from the EFA, and this solution was retained through PA. While validating the factor structure, CFA model fit indices showed an adequate fit to the data. Mean inter-item correlations, corrected item-total correlations, and internal consistency reliabilities fall within the acceptable ranges. MGCFA revealed that the CMARS can invariably measure the mindful attention regulation across gender. The relationship of CMARS with depression, stress, and mindfulness components indicated the convergent validity of the measure. Conclusions Altogether, the CMARS has been found to be a valid instrument for assessing students’ classroom attention regulation skills and identifying areas for improvement. Preregistration This study is not preregistered.

Bangladeshi fishermen and Agri farmers are particularly at risk from lightning strikes. There is little evidence of this population’s response, especially in rural locations at risk of lightning strikes. This research aims to know how these vulnerable people in northeastern Bangladesh react to lightning. 582 Agri farmers and fishermen participated in our face-to-face Knowledge, Attitude, and Practice (KAP) survey. Multiple regression analyses and descriptive statistics have been performed. Even though lightning is frequent, none had ever participated in lightning training. About 81% did not hear anything about lightning in the news. However, almost 80% had lightning-related knowledge, and 90% had a positive attitude. Fewer than half of the people surveyed had taken any lightning practices. Knowledge is related to occupation, monthly income, location, attitude, and practices; (p <0.05). On the other hand, attitude was linked to factors including age, occupation, monthly income, geographic region, and knowledge. There was an association between practices with monthly income, location, and knowledge. Better lightning protection could be possible with more thorough lightning safety training. Relevant stakeholders such as government agencies, local authorities, and NGOs should take steps to change people’s responses to lightning. They can conduct massive lightning-related campaigns, implement improved safety procedures, and provide intensive training.

This article intends to assess flood susceptibility mapping in Meghna River basin (MRB) and identified flood susceptible regions using three benchmark models including random forest (RF), support vector machine (SVM) and bagging with Naïve Bayes (NB) stacking ensemble algorithms (e.g. RF-NB; SVM-NB and Bagging-NB). The flood sample was partitioned into a training set (70%), and a validation set (30%), and the capability of prediction of flood-influencing variables was quantified by the multi-collinearity test. Several statistical metrics and Area Under the Receiver Operating Characteristics (AUROC) technique were applied to evaluate the techniques’ performance and precision. The outcomes showed that the significant factors influencing flash floods include rainfall, distance from the river and river density. The NB-Bagging outperforms (≈ a prediction accuracy of 95.1%) than other models in predicting the risk of flooding in the MRB. Results obtained from NB-Bagging showed that 12% and 21% of the basin were demarcated as having high and very high flood susceptibility, respectively. This article identified that rainfall and distance from the river were the two most driving factors influencing flooding in the MRB. The present work will aid decision-makers and local authorities determine flood conditioning problems and efficient flood risk management to lessen the consequences.

The study examined health safety issues among semi-intensive shrimp farmers in southwestern Bangladesh. The study assessed semi-intensive shrimp farmers’ knowledge, attitudes, and practices (KAP) on health and safety during their farm activities. The KAP model examined working circumstances, exposures, health complaints, diseases, current health status, and job satisfaction. Face-to-face interviews were conducted with 158 semi-intensive shrimp farmers from Bangladesh’s Khulna, Satkhira, and Bagerhat districts. Type-based data analysis was done. We used Spearman’s rank correlation and multiple linear regression. Only 35% of respondents said that they knew the health safety of chemicals and pesticides used in semi-intensive shrimp farms and that safety training is needed, and all farmers wanted to attend when available. At least 74% of farmers used masks when handling pesticides, fertilizers, and chemicals. 40.50% of farmers used protective clothing, 91% cleansed their hands, legs, and face after each day’s work, and 94% felt that sanitization reduces pesticide, fertilizer, and chemical pollution. A significant positive correlation coefficient was established in KAP. Education significantly increased knowledge. Practices varied with health and safety training. Results suggest that attitudes determine practices, where knowledge is significantly associated with attitudes. A comprehensive health safety and hygiene training program for all shrimp farmers should be developed to raise awareness, reduce illness outbreaks, and preserve healthy living.

While many studies have explored the pros and cons of emergency online learning during the COVID-19 pandemic and its psychological impact on university students, little attention has been given to students' perspectives on adapting to evolving learning environments in the post-pandemic era. This research investigates the intricate dynamics of tertiary-level students' experiences during the transition from online learning, particularly emergency remote teaching (ERT) adopted during Covid-19 pandemic period, to traditional face-to-face learning in the post-pandemic era in Bangladesh. A survey methodology, incorporating both closed and open-ended questions, was employed to capture the diverse perspectives, adaptive strategies, and insights of 294 students across multiple universities in Bangladesh to gauge the awareness of students regarding this new educational landscape. The results unveiled a nuanced perspective, highlighting both the challenges and opportunities associated with online digital learning platforms, including technological, pedagogical, and social aspects. Despite the convenience of emergency online learning, only a minority of respondents, comprising 14%, found it to be more motivating compared to traditional classroom learning. A staggering 75% emphasized the importance of face-to-face contact, highlighting the irreplaceable value of in-person interaction in educational experience. Financial barriers emerged as a significant hurdle, with 41% of participants citing cost as the primary impediment to internet access. Additionally, 51% identified signal availability and strength issues as key challenges, underscoring the digital divide exacerbated by uneven access to technology and connectivity. Key findings indicate that while emergency online learning provided necessary continuity during the pandemic, it also posed significant challenges in motivation, engagement, and social interaction. However, amidst these challenges, a beacon of hope emerged in the form of technological integration. An overwhelming majority of students, constituting 79%, expressed a desire for instructors to leverage technology in traditional offline classes to enhance engagement and capture students' attention. These findings suggest a need for a balanced, hybrid approach that integrates the benefits of both online and offline learning, addressing the diverse needs and preferences of students in the post-pandemic era. Nevertheless, the transition to emergency online learning brought about its own set of challenges. A notable 35% of respondents, including those who strongly agreed, found interactions among students and between students and teachers to be more uncomfortable and challenging compared to the pre-COVID-19 era. Furthermore, half of the respondents (50%) perceived a decline in on-site class etiquette from pre-pandemic times, reflecting the broader societal shift in norms and behaviors in the wake of remote teaching and learning. The findings of this study have the potential to contribute valuable insights into the challenges and opportunities associated with transitioning between different learning modalities and may inform strategies for enhancing students' preparedness and resilience in future educational disruptions.

The atmosphere has been burdened by the augmented release of greenhouse gases, leading to the unfortunate consequences of global warming due to the combustion of fossil fuels. Consequently, the realms of energy have directed their attention toward sustainable alternatives like hydro energy in order to generate electricity. Methods for storing energy have the ability to ensure the provision of energy when it is needed, as long as the energy is stored at a time when renewable sources are available. Hydrogen is regarded as a promising substitute for conventional feedstocks due to its distinctive qualities such as being a clean and high-density energy source, devoid of harmful substances and environmentally friendly. Hydrogen serves as the primary fuel for fuel cells, and it can be generated through various means, including harnessing wind power or utilizing electrolysis methods to extract electricity from renewable sources. However, the secure, efficient, and cost-effective preservation of hydrogen remains a formidable obstacle that hinders the widespread adoption of hydrogen energy. While high-pressure hydrogen gas and cryogenic hydrogen liquid are two storage methods that have been employed, they fail to satisfy the aforementioned criteria. In order to surmount these limitations, the realm of research has predominantly focused on ceramic-based hydrogen storage materials in recent times. This article presents a comprehensive review of the innovative endeavors conducted on these systems, accompanied by a delineation of discoveries made in order to store the workable thresholds for the quantity of hydrogen that may be retained in hydrogen storage systems utilizing ceramic materials.

The rapid urbanization of the Global South has intensified the challenges faced by urban slum communities, leaving them particularly vulnerable to socioeconomic shocks. Despite growing attention to urban poverty in these regions, limited research explores how such challenges intertwined with socioeconomic shocks during crises like the COVID-19 pandemic. This study aims to fill this gap by examining the experiences of slum residents in Bangladesh during the pandemic through the lens of social exclusion theory and urban resilience, focusing on the role of governmental responses. The research employed a qualitative research approach, incorporating in-depth interviews, key informant interviews, focus group discussions, observation methods, and thematic analysis to achieve its objectives. The findings reveal that the pandemic critically threatened the income and food security of the urban poor. Moreover, the study found that many slum residents had to leave the cities, faced social exclusion, and experienced a digital divide. Findings highlight significant shortcomings in government measures, emphasizing the need for stronger social safety net programs, public–private partnerships, and economic resilience strategies. The study emphasizes the importance of building urban resilience and fostering sustainable urban development by addressing the multi-dimensional vulnerabilities of slum communities. The study provides insights into crisis management and resilience building, offering evidence-based recommendations for mitigating the effects of urban poverty and enhancing urban sustainability.

Phytoplankton forms the foundation of the aquatic food chain, with their community composition dependent on environmental conditions. Research on phytoplankton communities in relation to environmental variables across diverse coastal ecosystems in Bangladesh remains limited and focusing on small or discrete areas. This study aimed to explore phytoplankton dynamics across contrasting ecosystems characterized by varying salinity levels (ranging from 0 to 36 ppt), encompassing riverine to marine ecosystem. We identified 48 species, encompassing 28 genera and 4 groups: diatoms (81.25%), blue-green algae (10.41%), dinoflagellates (4.18%), and green algae (4.16%), with Coscinodiscus concinnus (W. Smith) being the most dominant species. Seasonality significantly affected phytoplankton diversity and richness, with the highest diversity (H = 3.55) and richness (40 species) recorded in winter. Conversely, contrasting ecosystems had an effect on richness, but not on diversity with the highest 42 species in the estuarine ecosystems. ANOVA showed notable spatio-temporal heterogeneity in species abundance (p < 0.05), with a peak in the estuarine ecosystem during winter. Variability in environmental factors was also significant, with the exception of pH with seasons, while alkalinity and transparency showed insignificant differences among contrasting ecosystems. We identified distinct seasonal community successions, with a unique species composition in the winter, while the monsoon and pre-monsoon communities exhibited some degree of convergence. A strong correlation between species abundance and environmental factors was evident, especially salinity, alkalinity, and dissolved oxygen, playing major role in species distribution and seasonality. This study provides insights into phytoplankton dynamics and their response to environmental factors, providing baseline ecological information for ecosystem management in the region.