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Guava is a popular, export-promising, fast-growing fruit crop in Bangladesh that encompasses an important demand within the local market. We conducted a study of four types of guavas, specifically Thai guava, Strawberry guava, Kazi guava, and Deshi guava, by observing various parameters. The aim of this investigation to explore the physiochemical characteristics of the guava varieties procured from the local market of Noakhali district of Bangladesh. Physical characteristics such as weight, size, length, diameter, shape, and color were determined, as well as the nutritional status of guava varieties, including their non-reducing,reducing sugar , total sugar contents, vitamin C content, and the relationship between total sugar and vitamin C content, was assessed. According to the results, Kazi guava showed the highest fruit weight (220 gm), length (5.96 cm), and breadth (6.6 cm) compared to the other guava varieties available on the market. All the guava varieties had a similar color (green to pale green), while strawberry guava was red in color. Statistically significant variations were found among the chemical characteristics such as total sugar, reducing sugar, non-reducing sugar, total sugar, reducing sugar and the vitamin C content of various varieties. The highest value of reducing sugar (6.19%), non-reducing sugar (2.02%), and total sugar (8.55%) was found in Thai guava. Vitamin-C content was highest in Deshi guava (74.73 mg/100gm), whereas Kazi guava had the lowest value (61.20 mg/100 gm) of vitamin C content. However, this research explored that Thai guava had comparatively higher nutrition than others, but physical parameters were found to be best in the Kazi guava variety.

Understanding the adsorption mechanism of corticosteroids in the lung surfactant requires the knowledge of corticosteroid molecular interactions with lung surfactant monolayer (LSM). We employed coarse-grained molecular dynamics simulation to explore the action of hydrocortisone on an LSM comprised of a phospholipid, cholesterol and surfactant protein. The structural and dynamical morphology of the lung surfactant monolayer at different surface tensions were investigated to assess the monolayer compressibility. The simulations were also conducted at the two extreme ends of breathing cycles: exhalation (0 mN m-1 surface tension) and inhalation (20 mN m-1 surface tension). The impact of surface tension and hydrocortisone concentration on the monolayer compressibility and stability are significant, resulting the monolayer expansion at higher surface tension. However, at low surface tension, the highly compressed monolayer induces monolayer instability in the presence of the drug due to the accumulation of surfactant protein and drug. The constant area per lipid simulation results demonstrate that the surface pressure-area isotherms show a decrease in area-per-lipid with increased drug concentration. The drug-induced expansion causes considerable instability in the monolayer after a specific drug concentration is attained at inhalation breathing condition, whereas, for exhalation breathing, the monolayer gets more compressed, causing the LSM to collapse. The monolayer collapse occurs for inhalation due to the higher drug concentration, whereas for exhalation due to the accumulation of surfactant proteins and drugs. The findings from this study will aid in enhancing the knowledge of molecular interactions of corticosteroid drugs with lung surfactants to treat respiratory diseases.

Monitoring the flow characteristics through a twisted tube is an important topic because of its vast applications in several engineering sectors. As a result, highly motivated researchers have focused their efforts on discovering novel properties of fluid flow in a curved tube. A wide range of computational and selective experiments have been conducted to investigate flow characteristics in the square tube. However, a thorough study of the impacts of Coriolis-Energy force is less addressed in literature yet. The goal of this research is to precisely understand the transitional flow pattern and heat transfer in curved square domain. For this, we propose a numerical model for the laminar flow characterization through a twisted square tube. The current study examines the development of Dean vortices, which affect heat generation and thermal flow enhancement under various flow controlling parameters. The flow is driven by a constant pressure gradient parameter, the Dean number (Dn = 1000) over a considerable range of the Taylor number (−2500 ≤ Tr ≤ 2500), while the remaining parameters such as the Grashof number (Gr = 100) and the curvature (δ = 0.02) are kept constant. First, a bifurcation structure of steady solution curves is investigated and linear stability of the solutions is then examined. Time-dependent solution shows several flow instabilities including steady-state, periodic, multi-periodic, and chaotic oscillation. Furthermore, the temperature profiles with contours of axial and secondary flow velocities are exposed, which elucidates the impacts of Coriolis-energy force. The outcomes of the investigation demonstrate that the axial flow is pushed at the tube's inner sidewall for the positive rotation and behaves reversely for the negative rotation. The comprehensive analysis demonstrates that temperature-influenced buoyancy compulsion and centrifugal-Coriolis instability dominate the flow behavior affecting the fluid's characteristic and optimizing heat transmission. The implication of the current study will help researchers to better comprehend the fluid flow and heat transfer in internal heating/cooling/gas turbines, electric generators, biological systems, and some nano-filtration processes.

Short Birth Interval (SBI, defined as < 33 months interval between the two most recent births or < 24 months between one live birth to the next pregnancy) is a public health problem in most low- and lower-middle-income countries. Understanding geographic variations in SBI, particularly SBI hot spots and associated factors, may help intervene with tailored programs. This study identified the geographical hot spots of SBI in Bangladesh and the factors associated with them. We analyzed women’s data extracted from the 2017/18 Bangladesh Demographic and Health Survey and the healthcare facility data extracted from the 2017 Service Provision Assessment. SBI was the outcome variable, and it was defined as an interval between consecutive births of 33 months or less, as recommended by the World Health Organization. The characteristics of mothers and their partners were the explanatory variables. Moran’s I was used to examine the spatial variation of SBI in Bangladesh whereas the Getis-Ord Gi∗(d) was used to determine the hot spots of SBI. The Geographical Weighted Regression (GWR) was used to assess the predictors of SBI at the enumeration areas’ level. The variables included in the GWR were selected using the exploratory regression and ordinary least square regression model. Data of 5941 women were included in the analyses. Around 26% of the total births in Bangladesh had occurred in short intervals. A majority of the SBI hot spots were found in the Sylhet division, and almost all SBI cold spots were in the Rajshahi and Khulna divisions. No engagement with formal income-generating activities, high maternal parity, and history of experiencing the death of a child were significantly associated with SBI in the Sylhet division. Women’s age of 34 years or less at the first birth was a protective factor of SBI in the Rajshahi and Khulna divisions. The prevalence of SBI in Bangladesh is highly clustered in the Sylhet division. We recommend introducing tailored reproductive health care services in the hot spots instead of the existing uniform approach across the country.

The understanding of fluid flow and heat transfer (HT) through a rotating curved duct (RCD) is important for different engineering applications. The available literature improved the understanding of the fluid flow and HT through a large-curvature rotating duct. However, the comprehensive knowledge of fluid flow and HT through an RCD with small curvature is little known. This numerical study aims to perform fluid flow characterization and HT through an RCD with curvature ratio 0.001. The spectral based numerical approach investigates the effects of rotation on fluid flow and HT for the Taylor number -1000≤TTTT≤1500. A constant pressure gradient force, the Dean number Dn = 100, and a constant buoyancy force parameter, the Grashof number Gr = 500 are used for the numerical simulation. Fortran code is developed for the numerical computations and Tecplot software is used for the post-processing purpose. The numerical study investigates steady solutions and a structure of two-branches of steady solutions is obtained for positive rotation. The transient solution reports the transitional flow patterns and HT through the rotating duct, and two- to four-vortex solutions are observed. In case of negative rotation, time-dependent solutions show that the Coriolis force exhibits an opposite effect to that of the curvature so that the flow characteristics exhibit various flow instabilities. The numerical result shows that convective HT is increased with the increase of rotation and highly complex secondary flow patterns influence the overall HT from the heated wall to the fluid. To validate the numerical results, a comparison with the experimental data is provided, which shows that a good agreement is attained between the numerical and experimental investigations.

Background Short Birth Interval (SBI) is a public health problem in most low- and lower-middle-income countries. Understanding geographic variations in SBI, particularly SBI hot spots and associated factors, may help intervene with tailored programs. This study identified the geographical hot spots of SBI in Bangladesh and the factors associated with them. `Methods We analyzed women’s data extracted from the 2017/18 Bangladesh Demographic and Health Survey and the healthcare facility data extracted from the 2017 Service Provision Assessment. Moran’s I was used to examine the spatial variation of SBI in Bangladesh whereas the Getis-Ord G*i (d) was used to determine the hot spots of SBI. The Geographical Weighted Regression (GWR) was used to explore the spatial variation of SBI on explanatory variables. The explanatory variables included in the GWR were selected using the exploratory regression and ordinary least square regression model. Results Data of 5941 women were included in the analyses. Around 26% of the total births in Bangladesh had occurred in short intervals. A majority of the SBI hot spots were found in the Sylhet division, and almost all SBI cold spots were in the Rajshahi and Khulna divisions. No engagement with formal income-generating activities, high maternal parity, and history of experiencing the death of a child were significantly associated with SBI in the Sylhet region. Women’s age of 34 years or less at the first birth was a protective factor of SBI in the Rajshahi and Khulna divisions. Conclusion The prevalence of SBI in Bangladesh is highly clustered in the Sylhet division. We recommend introducing tailored reproductive health care services in the hot spots instead of the existing uniform approach across the country.

This paper presents an investigation on the waveguide of circularly polarised radial line slot array (RLSA) antennas to improve gain and radiation bandwidth. Two circularly polarised (CP) RLSA antennas were designed with two different waveguide configurations. In the first configuration the waveguide is fully filled with dielectric materials and in the second configuration the waveguide is partially filled with dielectric materials and rest of the waveguide is filled with air. Numerical results of these two CP-RLSA antennas with two different waveguide configurations are presented and compared. Significant improvements have been made in the 3-dB directivity bandwidth and aperture efficiency of the antenna having waveguide partially filled with dielectric material. The 3-dB directivity bandwidth was measured 6.2% and aperture efficiency increased to 55.5%. The CP-RLSA antenna has also achieved a peak directivity of 31.7 dBic and a gain of 31.2 dBic as compared to the directivity 30.1 dBic and gain 29.5 dBic, respectively achieved with the CP-RLSA antenna having waveguide fully filled with dielectric material.

This study investigates the effectiveness of resourcing in post-disaster housing reconstruction with reference to Cyclones Sidr and Aila in Bangladesh. Through evaluating three key theories- Build Back Better approach, Balance Scorecard approach and Dynamic Competency theories, the synthesis of literature, and empirical fieldwork, this research develops a dynamic theoretical framework that moves the trajectory of post-disaster housing reconstruction towards the reconstruction of more resilient houses. The ultimate goal of any post-disaster housing reconstruction project is to provide quality houses and to achieve high levels of satisfaction for beneficiaries. However, post-disaster reconstruction projects often fail in their stated objectives; only 10-20% housing needs are met, with most houses constructed on a temporary rather than permanent basis. A number of scholars have argued that access to resources can significantly increase the capacity and capability of disaster victims to rebuild their lives, including the construction of new homes. This study draws on structured interviews of 285 villagers affected by cyclones to investigate the effectiveness of resourcing in rebuilding houses after Cyclone Sidr in 2007 and Cyclone Aila in 2009. Furthermore, semi-structured interviews were conducted with 20 key stakeholders in UNDP, OXFAM, government officials, and national and international NGOs. The results of this study show that recovery rate of cyclone resilient houses that can withstand cyclone is very low and majority of the population are still vulnerable. Furthermore, multiple regression of survey data and thematic analyses of qualitative data indicate that access to resources, level of education, quality of building materials and income-generating activities of the respondents are critical for effective post-disaster recovery. Conversely, resource availability, lack of coordination among participant organisations, corruption and lack of access to appropriate land constituted significant obstacles to livelihood recovery. Finally, this study makes significant theoretical contributions to the theories of post-disaster recovery by introducing access to resources, land, level of education and level of income generating activities as new variables and it also identifies relevant method of measuring the effectiveness of resourcing for post-disaster housing reconstruction by employing parameters of rate of housing reconstruction, vulnerability reduction, poverty reduction, livelihood recovery, beneficiaries’ satisfaction and quality of reconstructed houses by which effectiveness of resourcing can be measured.