Facebook use and its predictive factors among students: Evidence from a lower- and middle-income country, Bangladesh

Background:Facebook is a popular social networking site in the modern world. It has an adverse effect such as impairing daily health and psychological health and also interpersonal relationships when the use becomes problematic.AimsTo examine problematic Facebook use (PFU) and its predictors among Bangladeshi students during the COVID-19 pandemic.MethodA cross-sectional online survey was conducted among 601 Bangladeshi students and collected data related to socio-demographic information, behavioral health, internet use behavior, depression, anxiety and problematic Facebook use [assessed using the Bergen Facebook Addiction Scale (BFAS)]. The data were analyzed using descriptive (frequencies and percentages) and inferential statistics (independent sample t-tests, one-way ANOVAs, correlations, and multivariable linear regression).ResultsThe results indicated that 29.1% of participants were problematic Facebook users (using cutoff ≥18 out of 30). Medical college students had higher mean score on PFU than other students (p < 0.001). In addition, the mean score of PFU was significantly higher among the students who were in a relationship (p = 0.001), did not engage in physical activity (p < 0.001), used the internet more than 5 h per day (p < 0.001), used social media (p < 0.001), and had depression or anxiety symptoms (p < 0.001). PFU was significantly associated with depression and anxiety among the whole sample. Predictive factors for PFU included relationship status, daily internet use time, gaming, social media use, depression, and anxiety. The model predicted almost 33.2% variance for PFU.ConclusionsFindings suggest interventions should be implemented for students with a special focus on medical students who had higher score of PFU than other types of students

Modification of CDV reactor for carbon nanomaterialns production

Chemical vapour deposition (CVD) reactor is one of the processes commonly used for carbon nanomaterial (CNM) production. This method is economical and provides high yield of good quality CNM. However, improvement of the CVD reactor system was necessary due to its long time requirement to complete each batch of production. A two-stage CVD was designed, locally fabricated and modified to overcome the limitations. Improvements included multistage system, which can be used to perform different processes such as floating catalyst reaction, fixed catalyst process, calcination, reduction and oxidation processes. A cooling system was added to reduce the production time. The system was further modified to increase the adsorption capacity of the products. The time requirement for one batch of run was reduced from 8 hours to 3 hours by improving the system

A population-based nationwide data set concerning the COVID-19 pandemic and serious psychological consequences in Bangladesh

This paper presents the dataset concerning knowledge, pre- ventive behavior, psychological consequences, and suicidal behavior regarding the COVID-19 pandemic in Bangladesh. Data were collected through an online based cross-sectional survey between April 1 and April 10 in 64 districts at the early stage of the COVID-19 pandemic in Bangladesh. A total of 10,067 participants’ data were recruited for analysis. The survey contained items concerning (i) socio-demographic in- formation, (ii) knowledge concerning COVID-19, (iii) behav- ior towards COVID-19, (iv) lockdown and economic issues, (v) assessment of fear of COVID-19, (vi) assessment of in- somnia, (vii) assessment of depression, and (viii) assessment of suicidal ideation. Data were analyzed utilizing SPSS (ver- sion 22) and are represented as frequencies and percentages based on responses to the whole survey. Given that the data were collected across the whole nation, government authori- ties and healthcare policymakers can use the data to develop various models and/or policies regarding preventive strate- gies and help raise awareness through health education to- wards COVID-19

Kinetics of cadmium adsorption by CNTs grown on PACs

Isotherms and kinetic models are useful tool for the investigation of adsorption process. Carbon nanotubes (CNTs) grown on powdered activated carbons (PACs) was used as novel adsorbent. Two isotherms and three kinetic models were studied for the removal of cadmium from water. The isotherms were Langmuir and Freundlich and the kinetic models were pseudo first order, pseudo second order and intraparticle diffusion models. Langmuir constants were qm = 69.759 mg/g, Kl = 0.223 and R2 = 0.924. The adsorption process was found more likely to follow Freundlich model with R2 value of 0.961, Kf of 9.215 and n of 3.015. Based on the kinetics study, the pseudo second order was the best fit with R2 of 0.996 and model constants were qe = 34.29 (mg/g) and K2 = 0.0013 (g/mg.min). Coefficients for the pseudo first order were qe= 21.145 (mg/g) and K1= 0.09 (min-1) with R2 of 0.936. The intraparticle kinetic model exhibited R2 value of 0.812 with Kd = 1.295 (g/mg.min0.5). CNTs after oxidative functionalization with KMnO4 were observed to be an efficient adsorbent for Cd2+ removal from water

A quantitative image analysis for the cellular cytoskeleton during in vitro tumor growth

The cellular cytoskeleton is a dynamic subcellular structure that can be a marker of key biological phenomena including cell division, organelle movement, shape changes and locomotion during the avascular tumor phase. Little attention is paid to quantify changes in the cytoskeleton while nuclei and cytoplasmic both are present in subcellular microscopic images. In this paper, we proposed a quantitative image analysis method to analyze subcellular cytoskeletal changes using a texture analysis method preceded by segmentation of nuclei, cytoplasm and ruffling regions (area except nuclei and cytoplasm). To test and validate this model we hypothesized that Mammary Serine Protease Inhibitor (maspin) acts as cytoskeleton regulator that mediates cell-extracellular matrix (ECM) adhesion in tumor. Maspin-a tumor suppressor gene shows multiple tumor suppressive properties such as increasing tumor cell apoptosis and reducing migration, proliferation, invasion, and overall tumor metastasis. The proposed method obtained separated ruffling regions from segmentation steps and then adopted gray–level histograms (GLH) and grey-level co-occurrence matrix (GLCM) texture analysis techniques. In order to verify the reliability, the proposed texture analysis method was used to compare the control and maspin expressing cells grown on different ECM components: plastic, collagen I, fibronectin and laminin. The results show that the texture parameters extracted reflect the different cytoskeletal changes. These changes indicate that maspin acts as a regulator of the cell-ECM enhancement process, while it reduces the cell migration. Overall, this paper not only presents a quantitative image analysis approach to analyze subcellular cytoskeletal architectures but also provides a comprehensive tool for the biologist, pathologist, cancer specialist, and computer scientist to understand cellular and subcellular organization of cells. In long term, this method can be extended to be used in live cell tracking in vivo, image informatics based point-of-care expert system and quantification of various complex architectures in organisms

The optimum condition for the synthesis of carbon nanofibers on activated carbon to remove lead from aqueous solution

Optimum process condition for the production of Carbon Nanofibers (CNFs) to remove lead ion (Pb) from aqueous solution is reported here. The CNFs were produced on the catalyst (Ni2+) impregnated palm oil-based cheap Powder Activated Carbon (PAC). Locally fabricated Chemical Vapour Deposition (CVD) system was used while acetylene (C2H2) was the carbon source. The porous nano-composite product is named “PAC-CNFs”, which was synthesized through a process using impregnated oil palm shell based PAC as a solid substrate. Design Expert 6.0.8 software was used to design the experimental plan and to determine the optimized process parameters for the growth of CNFs by using sorption capacity for Pb2+ by the PAC-CNFs adsorbent, as a response. The effect of different factors on the growth of CNFs including the temperature of CNFs growth (550 to 750 °C), time of growth (30 to 60 min), and the ratio of input C2H2/H2 gases (0.25 to 1.0) was evaluated. The predicted values for the sorption capacity of Pb2+ by the PAC-CNFs were in close agreement with the experimental data (R2 = 0.99). The optimal process condition: temperature for the growth of CNFs, time, and C2H2/H2 ratio was determined as 637 °C, 30 min, and 1.0, respectively. The CNFs grown under the optimized condition exhibited sorption capacity of 77 mg/g in removing Pb2+ from synthetic wastewater containing lead (Pb2+) ion

Carbon nanotubes grown on oil palm shell powdered activated carbon as less hazardous and cheap substrate

Multiwall carbon nanotubes were synthesised using fixed catalyst in a chemical vapor deposition reactor. The reactor system was locally built and used to grow carbon nanotubes (CNTs) on oil palm shell powdered activated carbon (PAC). The PAC was impregnated with Fe3+ catalyst through sonication process. The nano-micro composite produced in this study was named as “CNT-PAC”. Acetylene (C2H2) gas was used as carbon source compared to the use of toxic hydrocarbons such as benzene (C6H6). Synthesis parameters such as gas flow rates, temperature and reaction time were varied for high yield of the CNTs on powdered activated carbon. The CNT-PAC samples were characterized using field emission electron microscope and transmission electron microscope to confirm the growth of CNT as well as to study the morphology of the nano product. Selected well-grown CNT-PAC were further characterized using Fourier transform infrared spectroscopy, thermal gravimetric analysis and BET surface area measurement. The results showed that BET surface area was improved from 101.1 to 974.9 m2/g. The Zeta potential was − 46.1 mV. The zeta potential of the nano-micro composite indicated that the material will be in good dispersion in aqueous solution. The CNT-PAC product was also oxidized using KMnO4 to functionalise various radicals on the surfaces. The product could be potential as an adsorbent for gaseous and aqueous pollutants due to its high surface area and the presence of various functional groups