An abnormal rise in greenhouse gases in the atmosphere has triggered a range of environmental problems the foremost of which is global warming. CO2 is among the gases most responsible for the greenhouse effect. That is why, after the 1990s ,new tax regimes, also known as energy-carbon taxes, were put in place in an attempt to lower emissions. There is still an ongoing discussion as to whether tax regimes are working in practice. Certain studies have indicated that carbon taxes are effective or partially effective in preventing CO2 emissions. However, others assert that there is no causal relationship between carbon taxes and the lowering of greenhouse gas emissions. In this study, the annual data of 36 OECD countries in the period of 1990-2018 were used. To detect whether a carbon tax is effective in reducing greenhouse gas emissions, the panel data analysis method was employed. The results of the analysis revealed that carbon taxes have no effect on greenhouse gas emissions.

Klebsiella pneumoniae is an opportunistic pathogen that causes nosocomial infections and high morbidity and mortality in immunocompromised patients. Development of the high level of resistance to multiple antibiotics and lack of new drugs accentuate the need of new antimicrobial substances against this opportunistic pathogen. A novel functionalized bicyclo[3.2.1]octane derivative was initially screened against four Gram-positive bacteria and four Gram-negative bacteria by agar well diffusion method. Minimum inhibitory concentration (MIC) was determined against all test pathogens using resazurin microplate assay. Effect of test compound on growth curve of Klebsiella pneumoniae BDU-44 was evaluated by turbidimetric method. Time kill assay was performed to assess bacteriostatic or bactericidal nature and relationship between the concentration of compound and the net growth rate of Klebsiella pneumoniae BDU-44. Test compound exhibited better antimicrobial activity against Gram-negative bacteria. Klebsiella pneumoniae BDU-49 was most susceptible test culture with MIC 62.5 μg/mL. The growth curves of Klebsiella pneumoniae BDU-44 demonstrated that test compound could inhibit the growth and reproduction of bacteria. Time kill assay showed that test compound is bactericidal at 2× MIC and bacteriostatic at MIC. Overall, these data indicate that test substance could at as probable novel anti- Klebsiella pneumoniae compound in future.

2-hydroxyethyl methacrylate/Maleic acid (2-HEMA/MA) copolymer hydrogel was prepared using gamma radiation (60-Coγ) for possible use as an antibacterial agent. The effects of gamma radiation dose and monomer concentration on the polymerization yield were investigated. The physical properties such as water absorption and gel fraction of the prepared hydrogel were measured; it was found that the gel fraction increases and the swelling percentage decreases with increasing irradiation dose. The antimicrobial activity against certain pathogenic bacteria and yeasts, and the minimum inhibitory concentration (MIC) of the prepared hydrogel was investigated. The prepared hydrogel showed antimicrobial activities against all pathogens tested. The mechanism of action of 2-HEMA/MA hydrogel against selected bacteria (S. aureus, and E. coli) and yeast (C. albicans1) was determined by measuring the microbial cell membrane permeability, absorbing materials and protein, and leakage of potassium ions (K+) from cells. Overall studies indicated that 2-HEMA/MA hydrogel possesses a broad antimicrobial activity against all tested microorganisms and could be used as an antimicrobial agent in food and medical applications.

Metal Matrix Composites (MMC) are finding application in many fields like aerospace and automobile industries for their advantages such as lightweight and low cost. Among all the available non-traditional machining processes, Wire Electric Discharge Machining (WEDM) is found to be a suitable method for producing complex or intricate shapes in composite materials. In this study, Aluminium Metal Matrix Composite (AMMC) with 6% and 8% weight (wt) fraction of Al2O3 is prepared through stir casting process. The fabricated AMMC specimen is machined using WEDM considering various process parameters such as wt % of reinforcement, Gap Voltage (Vg), Peak Current (IP) Wire Tension(WT) and Dielectric Pressure (Pd). The output responses such as Machining Rate (MR) and Surface Roughness (Ra) of the slots are analysed by conducting L18 mixed Orthogonal Array (OA) experiments. The experiments are analysed using Techniques for Order Preference by Similarity to Ideal Solution (TOPSIS) and Analysis of Variance (ANOVA). Based on the analyses, the optimal combination of process parameter for better MR and Ra is wt %=6gm, Vg=53, Ip=8, WT=11, Pd=13 bar. The optimal level of process parameter for MR and Ra are 1.5mm/min and 3.648 µm respectively. Based on the ANOVA the peak current is found to have a significant influence on MR and Ra. Moreover, based on Scanning Electron Microscope (SEM) picture the presence of micro-ridges, reinforcement, micro-craters, micro-cracks, recast layers and oxide formation are analysed on the machined surface.

WHAT HEALTHCARE WORKERS KNOW ABOUT COVID-19 IN NOWSHERA PAKISTAN

In spite of reducing environmental pollution and the excessive consumption of fossil fuels, the adoption of electric vehicles (EVs) is still limited. The purpose of the current review is to explore and identify the potential barriers perceived by consumers in the adoption of EVs. The systematic review was carried out based on literature published in seven databases: “Web of Science”, “Science Direct”, “Springer”, “Wiley”, “Emerald”, “Sage”, and “Jstor” from 2011 to 2018. The current study incorporates 60 articles based on their appropriateness out of 2470 for the final analysis. To have an overall impression of the barriers associated with EVs adoption, barriers linked to similar problems were grouped into a single category. Five different categories “Technical”, “Cost”, “Demographics”, “Contextual”, and “Psychological” and several sub-categories in each group were recognized and proposed. Three barriers (A-Technical, D-Contextual, and E-Psychological) are considered as ‘primary’, these are the initial to stand up while consumers are faced with EVs. However, the study also indicates that barriers (B-Cost and C-Demographics) are considered as ‘secondary’, not noticed frequently, and mediate the three primary categories. The barriers explore in the current review are the potential to play as references for the implementer of the EVs and require attentive analyses.