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This paper presents a comparative performance analysis of PVC and MS blades in Archimedes Spiral Hydro Turbines (ASHT) for sustainable hydropower generation. There are two types of ASHT prototypes fabricated based on a three-dimensional (3D) design by varying the blade material; one was Poly Vinyl Chloride (PVC) made screw ASHT, and another was Mild Steel (MS) made ASHT. The thickness of PVC and MS was 4 mm and 1 mm, respectively. The generated voltage and current for 0.5 m, 1.0 m, and 1.5 m heads were analyzed, and the output power was compared with various shaft rotations based on the variation of the head. At the same head, voltage and current were obtained much more for MS-made ASHT. At 1.5m, higher voltage and current were investigated; the voltage and current were 10.2V and 0.57A for MS-made. MS-made ASHT exhibited 52.20% and 23.90% more voltage and current, respectively than PVC-made ASHT at 1.5m head. The maximum power was observed for MS-made ASHT, which was 5.82W at 502 rpm. This paper underscores the importance of balancing design parameters, blade material, and operating conditions to optimize ASHT for sustainable hydropower generation.

This study investigates the dynamic interplay between carbon levels and surface area variations on mild steel strength during the rolling process. Focused on understanding the nuanced relationship between these factors and steel durability, the research adopts a systematic approach. Controlled adjustments in carbon levels and surface area variations are employed to assess their impact on the structural integrity and tensile strength of mild steel. Through rigorous analysis and measurement, this study aims to unveil the intricate connections between carbon content, surface area alterations, and steel strength, offering critical insights for optimizing rolling processes in industrial settings. The experimental works have been conducted with carbon levels variations and surface area variations. The samples were tested in two different laboratories, however, the results of two laboratories are almost similar. The higher carbon content increases strength and yield strength varies with different carbon level and surface area. The surface area variations are affected the mechanical properties of mild steel. The maximum stress recorded was 700 MPa and the breaking point observed at 540 MPa. The findings aspire to contribute significantly to refining manufacturing techniques and developing more resilient steel products, thereby advancing our comprehension of material behavior in mechanical applications.

Yttria-Stabilized Zirconia (YSZ) based electrolytes of Solid Oxide Fuel Cell (SOFC) are widely used due to their higher ionic conductivity, stability, and availability. The present study focuses on improving the performance of YSZ-based electrolytes particularly by doping other particles into YSZ. TiO2 was doped into Fe2O3-8YSZ composite and the effects of TiO2 on the mechanical and physical properties of the composites were observed. The concentrations of TiO2 were varied by 0 wt%, 1 wt%, 3 wt%, and 5 wt% for different compositions of the composites. The samples were fabricated by the solid-state reaction method by pressing the powders at 250 MPa for 3 min and were sintered at 1250 °C for 4 h. The sintered samples were then undergone through characterization tests in terms of percentage of volume shrinkage, density, porosity, Diametral Tensile Strength (DTS), and microhardness. The highest values of volume shrinkage (34.83%), relative density (97.83%), DTS (36.58 MPa), hardness (965 HV), and the lowest porosity (2.17%) were found for 5 wt% TiO2 addition. Besides, the lowest values of volume shrinkage (28.44%), relative density (87.94%), DTS (3.24 MPa), microhardness (340 HV), and the highest porosity (12.06%) were found for Fe2O3-8YSZ composites without (0 wt%) TiO2 addition.

The present work indicates the fabrication of Aluminum Metal Matrix Composites (MMCs) reinforced jute stick charcoal powder (JSCP) using stir casting process and investigates different properties of fabricated composites. Mechanical properties such as flexural strength, tensile strength, hardness, and impact tests are investigated. Additionally, the morphology of the MMCs were analyzed using scanning electron microscopy (SEM). Furthermore, X-ray diffraction (XRD) analysis was used to identify the phase of the MMCs. From the investigation it was found that the tensile and flexural strength of the Al+3% JSCP composite decreased by 27.1% and 1.32% respectively compared to the Al+1% JSCP composite. On the other hand, impact strength and hardness were slightly greater for Al+3% JSCP composite. SEM analysis revealed micro-cavities and charcoal powder particle size and distribution differences. XRD patterns of the prepared composite revealed the presence of JSCP and lattice parameter of the composite. The investigation of surface roughness under different cutting speed reveals that, composite with 1% JSCP exhibited a higher surface roughness than the composite with 3% JSCP because the micro-cavity and porosity was less in Al+3% JSCP.

An extensive analysis on three distinct composite materials, namely Rattan Fiber Composite (RFC), Bamboo Fiber Composite (BFC), and Rattan/Bamboo Fiber Composite (RBFC), was conducted in this research. In scope of this investigation, water absorption (WA), swelling thickness (ST), density, thermogravimetric analysis (TGA), thermal conductivity, and fourier transform infrared spectroscopy (FTIR) of the composites were analyzed and studied. Density differences between composites are evident, with RBFC having the highest density due to its low water absorption and inherent hydrophobicity, while BFC, with its high-water absorption, exhibits the lowest density. With the increase of immersion time of the composite the WA increases. In case of salt solution, the WA is lower than the distilled water (DW). In case of ST, the BFC shows the maximum amount of ST. Overall, the maximum WA, ST, and density was 17.23%, 13.92 % and 1.12 gm/cm3 for BFC, BFC and RBFC respectively. The results of the Fourier Transform Infrared (FTIR) analysis provided evidence of the existence of hemicellulose, cellulose, lignin, and hydroxyl (-OH) groups in RBFC. RBFC shows maximum decomposition rate with 2.42 and 6.11 mg/min at 358 and 414 °C respectively. The maximum thermal conductivity was observed at RBFC with 0.266 W/m.K.

The kenaf fibers and Palmyra palm leaf stalk fibers (PPLSF) fiber were extracted using retting process then the composite was fabricated by Hand lay-up process using chemically treated unidirectional bilayer fibers mat. The fabricated composites undergone with mechanical properties such as tensile, flexural, impact test, and hardness. Three types of composites were manufactured by varying the weight percentage of fiber content, the composites were: Kenaf-Palmyra Palm Leaf Stalk-Kenaf Fiber Composite (KPKFC), Palmyra Palm Leaf Stalk-Kenaf-Palmyra Palm Leaf Stalk Fiber Composite (PKPFC), and Palmyra Palm Leaf Stalk-Kenaf Fiber Composite (PKFC). The KPKFC and PKPFC had shown significant mechanical properties. The maximum tensile and impact strength was found for PKPFC, the tensile and impact strength was 10.60 MPa and 17.37 J/cm2 respectively. The PKPFC had almost 60.18% and 66.72% more tensile and impact strength than KPKFC respectively. The highest flexural strength was obtained for KPKFC and flexural strength was 19.38 MPa. The KPKFC had 49.12% more flexural strength than PKPFC. The maximum hardness was obtained for KPKFC and the hardness was 25.4 Shore D.

BackgroundGlobally, over 81 million people use e-cigarettes, and the majority of them are young adults. Using e-cigarettes causes different types of adverse health effects both in adults and elderly people. Over time, using e-cigarettes has detrimental consequences on lung function, brain development and numerous other illnesses.MethodsThis study employed a mixed-methods conducted between June and September 2023, comprising two phases: Geographical Information System (GIS) mapping of available e-cigarette point-of-sale (POS) locations and conducting 15 in-depth interviews (IDIs) with e-cigarette retailers, along with 5 key informant interviews (KIIs) involving tobacco control activists and policy experts. ArcGIS was employed for spatial analysis, creating distribution and type maps, and buffer and multi-buffer ring analyses were conducted to assess proximity to hospitals and academic institutions. Data analysis involved descriptive statistics for GIS mapping and qualitative analysis for interview transcripts, utilizing a priori codebook and thematic analysis.ResultsA total of 276 POS were mapped in the entire Dhaka city. About 55 POS were found within 100m distance from academic institutions in Dhaka city, which offers the easy accessibility of young generations to e-cigarettes. The younger generation is becoming the major target for e-cigarettes because of their alluring flavors, appealing looks, and variation in flavors. Sellers have been using different marketing tactics such as postering, offering discounts and using internet marketing on social media. Moreover, they try to convince the customers by saying that e-cigarettes are 'not harmful' or 'less harmful'. However, retailers were mostly taking e-cigarettes from local wholesalers or distributors. Customers buy these products both from in-store and online services. Due to the absence of laws and regulations on e-cigarettes in Bangladesh, the availability, marketing, and selling of e-cigarettes are increasing alarmingly.ConclusionE-cigarette retail shops are mostly surrounded by academic institutions, and it is expanding. Besides, frequent exposure, easy accessibility, and tactful promotion encourage the younger generations to consume e-cigarettes. The government should take necessary control measures on manufacturing, storage, advertising, promotion, sponsorship, marketing, distribution, sale, import, and export in order to safeguard the health and safety of young and future generations.

In scope of this research, manufacturing and mechanical characterization of rattan and bamboo fiber reinforced vinyl ester composite material were carried out. Bamboo and rattan fiber was extracted by using retting process followed by chemical treatment to enhance mechanical properties. The composite was manufactured using bidirectional fiber mat in vacuum bag molding and hand layup process. The weight fraction between reinforcement and matrix was 24% and 76% respectively. Three types of composites were manufactured; Bamboo Fiber Composite (BFC), Rattan Fiber Composite (RFC), and Rattan (12%) and Bamboo (12%) Fiber Composite (RBFC). Different mechanical behavior of the composite was investigated, such as tensile strength, flexural strength, hardness, and impact strength. The maximum flexural and impact strength was found for RBFC with 57.66 MPa and 44.49 kJ/m2, respectively. It was found that about 29% and 17% of flexural strength and 29% and 78% of impact strength was improved for RBFC than BFC and RFC respectively. Finally, fabricated composites mechanical characteristics were compared to the Acrylonitrile Butadiene Styrene or ABS plastic materials mechanical characteristics.

BACKGROUND: The current study aims at evaluating the analgesic, anti-pyretic and anti-inflammatory properties of methanolic extract of the stem, bark and leaves of Launaea sarmentosa and Aegialitis rotundifolia roxb. RESULTS: The AELS and AEAR extract presented a significant (***p < 0.001) dose dependent increase in reaction time in writhing method and showed inhibition of 63.1% and 57.1% respectively at the doses of 400 mg/kg body weight while standard drug showed (P < 0.001) inhibition of 69.23%. In tail immersion method, AELS and AEAR showed maximum time of tail retention at 30 min in hot water i.e. 6.93 sec and 6.54 sec respectively at highest doses of 400 mg/kg body weight than lower dose while standard pentazocine showed reaction time of 7.62 sec. The AELS and AEAR extract also exhibited promising anti-inflammatory effect as demonstrated by statistically significant inhibition of paw volume by 32.48% and 26.75% respectively at the dose of 400 mg/kg body weight while the value at the dose of 200 mg/kg body weight were linear to higher dose at the 3rd hour of study. On the other hand, Standard indomethacin inhibited 40.13% of inflammation (***P < 0.001). In Cotton-pellet granuloma method, AELS and AEAR extract at the dose of 400 mg/kg body weight exhibited inhibition of inflammation of 34.7% and 29.1% respectively while standard drug showed (P < 0.001) inhibition of 63.22%. Intraperitoneal administration of AELS and AEAR showed dose dependent decrease in body temperature in brewer's yeast induced hyperthermia in rats at both doses. However, AELS significantly decreased body temperature (***p < 0.001) at 400 mg/kg compared to control. CONCLUSIONS: Present work propose that the methanolic extract of Launaea sarmentosa and Aegialitis rotundifolia roxb possesses dose dependent pharmacological action which supports its therapeutic use in folk medicine possibly mediated through the inhibition or blocking of release of prostaglandin and/or actions of vasoactive substances such as histamine, serotonin and kinins.

BACKGROUND: The study was conducted to evaluate the in vitro antimicrobial activity, cytotoxic, and membrane stabilization activities, and in vivo antiemetic and antipyretic potentials of ethanolic extract, n-hexane and ethyl acetate soluble fractions of Spilanthes paniculata leaves for the first time widely used in the traditional treatments in Bangladesh. RESULTS: In antipyretic activity assay, a significant reduction (P < 0.05) was observed in the temperature in the mice tested. At dose 400 mg/kg-body weight, the n-hexane soluble fraction showed the effect (36.7 ± 0.63°C ) as like as the standard (dose 150 mg/kg-body weight) after 5 h of administration. Extracts showed significant (P < 0.001) potential when tested for the antiemetic activity compared to the standard, metoclopramide. At dose 50 mg/kg-body weight, the standard showed 67.23% inhibition, whereas n-hexane and ethyl acetate soluble fractions showed 37.53% and 24.93% inhibition of emesis respectively at dose 400 mg/kg-body weight. In antimicrobial activity assay, the n-hexane soluble fraction (400 µg/disc) showed salient activity against the tested organisms. It exerts highest activity against Salmonella typhi (16.9 mm zone of inhibition); besides, crude, and ethyl acetate extracts showed resistance to Bacillus cereus and Bacillus subtilis, and Vibrio cholera respectively. All the extracts were tested for lysis of the erythrocytes. At the concentration of 1mg/ml, ethanol extract, and n-hexane and ethyl acetate soluble fractions significantly inhibited hypotonic solution induced lysis of the human red blood cell (HRBC) (27.406 ± 3.57, 46.034 ± 3.251, and 30.72 ± 5.679% respectively); where standard drug acetylsalicylic acid (concentration 0.1 mg/ml) showed 77.276 ± 0.321% inhibition. In case of heat induced HRBC hemolysis, the plant extracts also showed significant activity (34.21 ± 4.72, 21.81 ± 3.08, and 27.62 ± 8.79% inhibition respectively). In the brine shrimp lethality bioassay, the n-hexane fraction showed potent (LC50 value 48.978 µg/ml) activity, whereas ethyl acetate fraction showed mild (LC50 value 216.77 µg/ml) cytotoxic activity. CONCLUSIONS: Our results showed that the n-hexane extract has better effects than the other in all trials. In the context, it can be said that the leaves of S. paniculata possess remarkable pharmacological effects, and justify its folkloric use as antimicrobial, antipyretic, anti-inflammatory, and antiemetic agent. Therefore, further research may be suggested to find possible mode of action of the plant part.

ABSTRACT Background and Aims This article explores antibiotic resistance as a critical public health issue in Bangladesh, emphasizing its growing threat to the nation's healthcare system. As a developing country, Bangladesh faces unique challenges in managing this crisis, with antibiotic resistance posing significant risks due to its multidimensional problems to both individual health and the broader population. Methods We searched for relevant pieces of literature that discuss the antibiotic resistance problem both from a global and national perspective. Based on the importance and our objectives we selected the relevant articles. The perspective was written using the evidence and information available in those articles. Results Key factors contributing to the rise of antibiotic resistance include the irrational use and prescription of antibiotics in both healthcare settings and agriculture, incomplete doses of antibiotics, and insufficient public awareness. The article also discusses potential policy recommendations, such as the implementation of stricter antimicrobial stewardship programs, enhanced surveillance systems, and public education campaigns to reduce the misuse of antibiotics. Conclusion In conclusion, antibiotic resistance in Bangladesh requires urgent attention and coordinated efforts from all sectors of society to prevent further deterioration of public health and safeguard future generations.

Abstract Background Hospital cabins are a part and parcel of the healthcare system. Most patients admitted in hospital cabins reside in bedridden and immobile conditions. Though different kinds of systems exist to aid such patients, most of them focus on specific tasks like calling for emergencies, monitoring patient health, etc. while the patients’ limitations are ignored. Though some patient interaction systems have been developed, only singular options like touch, hand gesture or voice based interaction were provided which may not be usable for bedridden and immobile patients. Methods At first, we reviewed the existing literature to explore the prevailing healthcare and interaction systems developed for bedridden and immobile patients. Then, a requirements elicitation study was conducted through semi-structured interviews. Afterwards, design goals were established to address the requirements. Based on these goals and by using computer vision and deep learning technologies, a hospital cabin control system having multimodal interactions facility was designed and developed for hospital admitted, bedridden and immobile patients. Finally, the system was evaluated through an experiment replicated with 12 hospital admitted patients to measure its effectiveness, usability and efficiency. Results As outcomes, firstly, a set of user-requirements were identified for hospital admitted patients and healthcare practitioners. Secondly, a hospital cabin control system was designed and developed that supports multimodal interactions for bedridden and immobile hospital admitted patients which includes (a) Hand gesture based interaction for moving a cursor with hand and showing hand gesture for clicking, (b) Nose teeth based interaction where nose is used for moving a cursor and teeth is used for clicking and (c) Voice based interaction for executing tasks using specific voice commands. Finally, the evaluation results showed that the system is efficient, effective and usable to the focused users with 100% success rate, reasonable number of attempts and task completion time. Conclusion In the resultant system, Deep Learning has been incorporated to facilitate multimodal interaction for enhancing accessibility. Thus, the developed system along with its evaluation results and the identified requirements provides a promising solution for the prevailing crisis in the healthcare sector. Trial Registration Not Applicable.

Viral epidemics of variable frequency and severity have wreaked havoc and panic across the world. The Nipah virus (NiV), which has been linked to multiple outbreaks, mostly in South and Southeast Asia, is regarded as one of the deadliest in the world. In Bangladesh, seasonal outbreaks of encephalitis caused by the NiV have occurred annually since 2003. In particular, NiV has numerous characteristics that highlight its potential as a pandemic danger, such as its human-to-human transmission capability and its propensity to infect humans directly from natural reservoirs and/or from other animals. Numerous types of research investigate the pathophysiology and viral mechanisms of disease progression. The NiV and its disease have been studied thoroughly but attempts to implement preventive techniques have met cultural and social obstacles. This review highlights the NiV outbreaks, and its present status, the preventative and control measures implemented, the potential causes of the outbreaks in Bangladesh, and the precautions that must be taken by both government and nongovernment entities to contain the outbreaks and assure a future with fewer or no occurrences.

The genus Zingiber consists of about 85 species and many of these species are used as food, spices, and medicines. One of the species, Zingiber montanum (J. Koenig) Link ex A. Dietr. is native to Southeast Asia and has been extensively used as traditional medicines and food. The aim of this review was to collect and critically analyze the scientific information about the bioactive compounds and pharmacological activities of Z. montanum with focus on one of the main components, zerumbone (ZER). Various studies have reported the analysis of volatile constituents of the essential oils from Z. montanum. Similarly, many phenylbutanoids, flavonoids and terpenes were also isolated from rhizomes. These essential oils, extracts and compounds showed potent antimicrobial, anti-inflammatory and antioxidant activities among others. Zerumbone has been studied widely for its anticancer, anti-inflammatory, and other pharmacological activities. Future studies should focus on the exploration of various pharmacological activities of other compounds including phenylbutanoids and flavonoids. Bioassay guided isolation may result in the separation of other active components from the extracts. Z. montanum could be a promising source for the development of pharmaceutical products and functional foods.

Zingiber montanum (J. Koenig) Link ex A. Dietr. (Zingiberaceae) is known as “Banada” in Bangladesh, and the rhizomes are frequently used in traditional medicines for the treatment of constipation, dyspepsia, flatulence, stomach bloating, and as mosquito repellant. In this study, dried rhizomes were extracted successively with 95% and 50% ethanol and the combined extract was then subjected to various column chromatographic methods to isolate one sesquiterpenoid derivative, zerumbone (1) and five kaempferol derivatives, i.e., kaempferol 3-O-methyl ether (2), kaempferol 3-O-α-rhamnopyranoside (3), kaempferol 3-O-α-(4”-O-acetyl)rhamnopyranoside (4), kaempferol 3-O-α-(3”-O-acetyl)rhamnopyranoside (5), and kaempferol 3-O-α-(3”,4”-di-O-acetyl)rhamnopyranoside (6). All compounds except 1 were isolated for the first time from the title plant.