Design, Construction and Performance Study of a Solar Assisted Tri-cycle

Solar energy is one of the important sources of renewable energy which can be a feasible alternative to fossil fuels. There are many works has been done in order to incorporate solar energy to everyday transportation including tricycle. However, most of the tricycle develops are expensive and not feasible for developing countries. In this study, a cheaper solar tricycle with more capability of utilizing the solar energy is designed for developing countries. The main content of the tricycle is Solar PV panel, Brushless PMDC motor, controller, and battery. The power transmission of the solar tricycle is also simple. It is found that tricycle serves 24% back up for running, by the solar panel. Also, the total construction cost of the tricycle is only 240$ with near about zero impact on the environment. This paper highlights the advantages of the dual mode of charging, including the economic and environmental feasibility of the tricycle

Prevalence and Antibiotic Resistance Pattern of Escherichia coli Isolated from Raw Dairy Milk

E. coli is one of the most important food borne pathogen, which could be transmitted by milk and milk products. To assess the role of dairy milk as the source of drug resistant E. coli, we examined 50 raw dairy milk samples (25-farm milk + 25-market milk) from some selected areas of Bangladesh by cultural, morphological, biochemical and antimicrobial sensitivity tests. In the preliminary observation, the mean total aerobic mesophilic count of market and farm raw milk samples were 8.98 and 8.68 log CFU/ml, while mean coliform count were 4.20 and 3.03 log CFU/ml respectively. Thirty-three E. coli isolates were recovered from collected samples (66% 33 of 50) and this pathogen was more prevalent in market milk (76%, 19 of 25) than farm milk (56%, 14 of 25). In addition, most of the isolated E. coli exhibited resistance against ampicillin and cefotaxime. This result shows that, the raw dairy milk and its products could be a source of human drug resistant E. coli

Targeting SARS-CoV-2 main protease (Mpro) and human ACE-2: A virtual screening of carotenoids and polyphenols from tomato (Solanum lycopersicum L.) to combat Covid-19

Background Human angiotensin-converting enzyme-2 (ACE-2) and severe acute respiratory syndrome corona virus-2 (SARS-CoV-2) main protease (Mpro) have been established as the prime targets to restrict viral invasion and replication inside the host, respectively. Methods The current study delineated the SARS-CoV-2 Mpro as well as human ACE-2 inhibitory potential of carotenoids and polyphenols from tomato (Solanum lycopersicum L.) via in-silico interaction studies. Results Our drug-likeness studies showed that the selected carotenoids and polyphenols exhibited acceptable Lipinski’s score and ADME determinants. Further, in-silico molecular modelling studies revealed that β-carotene, among other carotenoids, topped the binding score (ΔG: −6.75 kcal/mol; Ki: 11.32 μM) against SARS-CoV-2 Mpro, whereas, cyanidin was the best inhibitor of SARS-CoV-2 Mpro (−7.24 kcal/mol; Ki: 4.92 μM) amongst polyphenols. Similarly, α-carotene from carotenoids exhibited strongest human ACE-2 inhibitory activity (ΔG: −8.85 kcal/mol; Ki: 326.13 μM), whereas, cyanidin from polyphenols showed best binding affinity against human ACE-2 (ΔG: −7.24 kcal/mol; Ki: 4.89 μM). In contrast, 6-(ethylamino)-pyridine-3-carbonitrile, standard inhibitor of SARS-CoV-2 Mpro, exhibited comparatively weaker binding (ΔG: −4.78 kcal/mol; Ki: 267.49 μM), whereas, telmisartan (reference ACE-2 inhibitor) also exhibited lesser affinity (ΔG: −6.40 kcal/mol; Ki: 20.40 μM). Further exploration via MDS studies also validated the dynamic behavior and stability of protein-ligand complexes as evident by desirable RMSD, RMSF, Rg, and SASA. Conclusion The current study established carotenoids and polyphenols from S. lycopersicum L. as finer substitutes of reference standards against SARS-CoV-2 Mpro and human ACE-2 activity in combating SARS-CoV-2 infection

pH-responsive release of ciprofloxacin hydrochloride from micro-, nano-, and functionalized nanocellulose

This research evaluated pH-responsive release characteristics for the drug (ciprofloxacin hydrochloride) from micro-, nano-, and functionalized cellulose forms. Nanocrystalline cellulose (NCC) was prepared from microcrystalline cellulose (MCC) by sulfuric acid hydrolysis. The aldehyde (–CHO) groups were introduced at the carbon-2 (C-2) and carbon-3 (C-3) positions of glucose moiety of the cellulose network by selective oxidation to form di-aldehyde nanocellulose (DANC). The conversion was validated by chemical, spectroscopic, morphological, and crystallographic analysis. Drug binding capacity (mg/g) of DANC was higher (200.8 mg/g) compared to NCC (138.3 mg/g) and MCC (120.2 mg/g), respectively. The increase in pH from 2.5 to 8.5 enhanced drug release for all the excipients. At pH 2.5, slow release of the drugs was observed. In 6 h, DANC released 44.7 % of the loaded drug at pH 2.5. However, drug release reached equilibrium (84.8 % of loaded drug) within 10 min at pH 8.5. The release kinetics at acidic pH were validated using zero-order, first-order, Higuchi, and Korsmeyer-Peppas kinetics models. Higuchi and Korsmeyer–Peppas' kinetic models interpreted drug release phenomena with a good fit. This implies that diffusion, dissolution, swelling, and slight erosion contribute to drug release. The results suggest that selective functionalization can be applied to cellulose for its potential applications in pH-responsive drug delivery, and therefore, the functionalized cellulose deserves immediate attention