Gastroprotective potential and mechanisms of action of Hedera nepalensis

Abstract Hedera nepalensis (H. nepalensis) , belonging to the family Araliaceae, is a medicinal plant traditionally used to treat stomach problems. The current study investigated the gastroprotective potential and the mechanism of action of H. nepalensis in diclofenac-and ethanol-induced ulcer models. Anti-oxidant and lipid peroxidation inhibitory prospects of H. nepalensis were checked out by free radical scavenging assay and UV spectrophotometer respectively. Effect of H. nepalensis on the pH, gastric total acidity of gastric juice and protective effects of H. nepalensis against ulcer models have been examined. Histopathological studies have been carried out. The aqueous methanol extract of H. nepalensis (100 µg/mL) showed anti-oxidant (83.55%) and lipid peroxidation inhibitory (70.88%) potential at 1000 µg/mL; the extract had no buffer potential. The extract (400 mg/kg) significantly (81.12% and 63.46%) showed gastroprotective effect in diclofenac and ethanol-induced rat ulcer models respectively. Histopathological studies confirmed the biochemical findings. FTIR analysis showed the presence of carboxylic acid, alkanes, conjugated alkanes, aldehydes and alkyl-aryl ethers. Gallic acid, M-coumaric acid and quercetin were found by HPLC analysis. H. nepalensis exhibited significant protection against diclofenac and ethanol induced gastric damage by anti-oxidant and lipid peroxidation suppression effects suggesting potential broad utility in treatment of diseases characterized with gastric damage.

Nanocomposite-Enhanced Efficient Evaporation System for Solar-Driven Seawater Desalination-An Optimized Design for Clean Water Production.

Solar-driven evaporation is a promising technology for desalinating seawater and wastewater without mechanical or electrical energy. The approaches to obtaining fresh water with higher evaporation efficiency are essential to address the water-scarcity issue in remote sensing areas. Herein, we report a highly efficient solar evaporator derived from the nanocomposite of anatase TiO2/activated carbon (TiO2/AC), which was coated on washable cotton fabric using the dip-dry technique for solar water evaporation. The ultra-black fabric offers enhanced solar absorption (93.03%), hydrophilic water transport, and an efficient evaporation rate of 1.65 kg/m2h under 1 kW m-2 or one sun solar intensity. More importantly, the sideways water channels and centralized thermal insulation of the designed TiO2/AC solar evaporator accumulated photothermal heat at the liquid and air interface along with an enhanced surface temperature of 40.98 °C under one sun. The fabricated solar evaporator desalinated seawater (3.5 wt%) without affecting the evaporation rates, and the collected condensed water met the standard of drinking water set by the World Health Organization (WHO). This approach eventually enabled the engineering design groups to develop the technology pathways as well as optimum conditions for low-cost, scalable, efficient, and sustainable solar-driven steam generators to cope with global water scarcity.

Interfacial Photothermal Heat Accumulation for Simultaneous Salt Rejection and Freshwater Generation; an Efficient Solar Energy Harvester.

Water scarcity has emerged as an intense global threat to humanity and needs prompt attention from the scientific community. Solar-driven interfacial evaporation and seawater desalination are promising strategies to resolve the primitive water shortage issue using renewable resources. However, the fragile solar thermal devices, complex fabricating techniques, and high cost greatly hinder extensive solar energy utilization in remote locations. Herein, we report the facile fabrication of a cost-effective solar-driven interfacial evaporator and seawater desalination system composed of carbon cloth (CC)-wrapped polyurethane foam (CC@PU). The developed solar evaporator had outstanding photo-thermal conversion efficiency (90%) with a high evaporation rate (1.71 kg m-2 h-1). The interfacial layer of black CC induced multiple incident rays on the surface allowing the excellent solar absorption (92%) and intensifying heat localization (67.37 °C) under 1 kW m-2 with spatially defined hydrophilicity to facilitate the easy vapor escape and validate the efficacious evaporation structure using extensive solar energy exploitation for practical application. More importantly, the long-term evaporation experiments with minimum discrepancy under seawater conditions endowed excellent mass change (15.24 kg m-2 in consecutive 8 h under 1 kW m-2 solar irradiations) and promoted its operational sustainability for multi-media rejection and self-dissolving potential (3.5 g NaCl rejected from CC@PU surface in 210 min). Hence, the low-cost and facile fabrication of CC@PU-based interfacial evaporation structure showcases the potential for enhanced solar-driven interfacial heat accumulation for freshwater production with simultaneous salt rejection.

Nuclear Disaster Preparedness Level of Medical Responders in Pakistan.

Pakistan is a country with nuclear capability in a region sharing borders with 2 other nuclear powers-that is, India to the east and China to the northeast. This geographic positioning makes the area a nuclear flash point. It is therefore imperative to have commensurate health-care facilities to meet any eventualities. Although Pakistan is trying to improve medical facilities for the people, health-care facilities are already overwhelmed with patients because of the large population of the country. The current study was conducted to evaluate the level of awareness and preparedness of medical responders for nuclear and radiological disasters in public hospitals in the major cities of Pakistan. Methods: A detailed questionnaire covering all aspects of the study was designed and discussed with the people most concerned, including health-care workers in the field of medicine, nuclear sciences, and disaster management in Pakistan. It was adopted on the basis of early studies on the subject, with necessary modifications to fulfill the requirements at Pakistan's level. Semistructured interviews were also conducted with key personnel of different response agencies in Pakistan. Results: Of 880 surveys, 554 were completed and collected from medical providers in different hospitals across the country. The respondents included doctors, nurses, and medical assistants from emergency and nonemergency departments. They are aware of the catastrophic consequences of nuclear disaster and are willing to respond to these kinds of disasters voluntarily, but they are not satisfied with their level of preparedness and awareness regarding nuclear and radiological disasters. Conclusion: Although medical responders have good educational backgrounds and knowledge in their specific fields and are quite active and energetic in their response to conventional injuries and natural disasters, they feel a dire need to enhance their level of knowledge about and preparedness for unconventional disasters and injuries such as those caused by nuclear or radiological events.

Environmental impacts of shifts in energy, emissions, and urban heat island during the COVID-19 lockdown across Pakistan.

Restrictions on human and industrial activities due to the coronavirus (COVID-19) pandemic have resulted in an unprecedented reduction in energy consumption and air pollution around the world. Quantifying these changes in environmental conditions due to government-enforced containment measures provides a unique opportunity to understand the patterns, origins and impacts of air pollutants. During the lockdown in Pakistan, a significant reduction in energy demands and a decline of ∼1786 GWh (gigawatt hours) in electricity generation is reported. We used satellite observational data for nitrogen dioxide (NO2), carbon monoxide (CO), sulphur dioxide (SO2), aerosol optical depth (AOD) and land surface temperature (LST) to explore the associated environmental impacts of shifts in energy demands and emissions across Pakistan. During the strict lockdown period (March 23 to April 15, 2020), we observed a reduction in NO2 emissions by 40% from coal-based power plants followed by 30% in major urban areas compared to the same period in 2019. Also, around 25% decrease in AOD (at 550 nm) thickness in industrial and energy sectors was observed although no major decrease was evident in urban areas. Most of the industrial regions resumed emissions during the 3rd quarter of April 2020 while the urban regions maintained reduced emissions for a longer period. Nonetheless, a gradual increase has been observed since April 16 due to relaxations in lockdown implementations. Restrictions on transportation in the cities resulted in an evident drop in the surface urban heat island (SUHI) effect, particularly in megacities. The changes reported as well as the analytical framework provides a baseline benchmark to assess the sectoral pollution contributions to air quality, especially in the scarcity of ground-based monitoring systems across the country.

The effects of regional climatic condition on the spread of COVID-19 at global scale.

The pandemic outbreak of the novel coronavirus epidemic disease (COVID-19) is spreading like a diffusion-reaction in the world and almost 208 countries and territories are being affected around the globe. It became a sever health and socio-economic problem, while the world has no vaccine to combat this virus. This research aims to analyze the connection between the fast spread of COVID-19 and regional climate parameters over a global scale. In this research, we collected the data of COVID-19 cases from the time of 1st reported case to the 5th June 2020 in different affected countries and regional climatic parameters data from January 2020 to 5th June 2020. It was found that most of the countries located in the relatively lower temperature region show a rapid increase in the COVID-19 cases than the countries locating in the warmer climatic regions despite their better socio-economic conditions. A correlation between metrological parameters and COVID-19 cases was observed. Average daylight hours are correlated to total the COVID-19 cases with a coefficient of determination of 0.42, while average high-temperature shows a correlation of 0.59 and 0.42 with total COVID-19 cases and death cases respectively. The finding of the study will help international health organizations and local administrations to combat and well manage the spread of COVID-19.

Comparison of H2S gas destruction potential using TIO2 nanofibers and nanoparticles.

TiO2 nanoparticles and nanofibers have been used to carry out a comparative study of the destruction of H2S gas. Effects of sulphur doping have also been incorporated to assess the maximum destruction potential of the nanomaterials. An analysis has been made in this paper to evaluate and compare the performance of pure and sulphur-doped TiO2 nanoparticles and nanofibers for the destruction of H2S gas using photocatalysis under laboratory conditions. Regression modelling has been performed to ascertain the individual degradation rates of the nanoparticles and nanofibers. In addition, oxidation rates of H2S gas using the nanoparticles and nanofibers have been used to further elucidate our findings. It was observed that the destruction potential of nanofibers was 10 times more as compared to nanoparticles.

A comparison of TiO2 nanoparticles and nanotubes for catalytic gas phase destruction of H2S gas at high temperatures.

Reduction of H2S gas over Sulphur doped TiO2 nanoparticles and TiO2 nanotubes was studied in this work. Fixed bed catalytic system was used for the catalytic reduction of H2S gas at a high temperature of 450 degrees C under laboratory conditions. 99.97% reduction was achieved using S-doped TiO2. 2.89% Sulphur was adsorbed on S-doped TiO2 nanoparticles in the form of Ti(SO4)2, while 95.6% reduction was achieved in case of TiO2 nanotubes and the sulphur adsorption was 2.67%. The XRD, SEM, and EDX techniques were carried out to characterize the nanoparticles and nanotubes, while gas reduction analysis was carried out using GC-MS for gas samples.