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841.
Purpose

This study aims at finding the environmental impacts generated by an electric disk insulator supply chain, used for the distribution of electricity by an open wire system, through a case study. This study also aims at benchmarking the environmental impacts of an electric insulator manufacturing process by taking ideal condition of zero waste as reference.

Methods

Cradle-to-grave life cycle assessment (LCA) has been carried out by following the guidelines provided in ISO 14040 series standards and using Umberto NXT software. ReCiPe endpoint and ReCiPe midpoint impact assessment methodologies have been used to calculate environmental impacts under various categories. The primary data has been collected from a medium-scale manufacturer of electric disk insulators located at Bikaner in north-west India. The secondary data has been taken from ecoinvent 3.0 database and literature. The environmental impacts using endpoint assessment (ecosystem quality, human health, and resources) and midpoint assessment (climate change, fossil depletion, human toxicity, metal depletion, ozone depletion, terrestrial acidification, and water depletion) categories have been computed. Finally, the results are compared and benchmarked against the ideal zero waste condition using three different production scenarios. The limitation of this study is that the data has been collected only from one manufacturer and its supply chain.

Results and discussion

It has been found that the use of steel, electricity, and fuel; transportation of product; and disposal of water generate high environmental impacts in the supply chain. It has also been found that in the electric disk insulator supply chain, the raw material extraction phase has the highest environmental impacts followed by manufacturing, disposal, transportation, and installation phases. This study has also found that benchmark scenario “B” (zero waste condition) is environmentally more efficient in comparison to scenario “A” (actual recycling condition) and scenario “C” (maximum waste condition).

Conclusions

This study has identified that raw materials, resources, and processes in the supply chain of an electric disk insulator manufacturing unit are responsible for the environmental damage. The various manufacturing processes and installation of the electric disk insulators are similar for all manufacturers except the machinery efficiency and the generated waste. This study provides environmental impacts associated with an electric disk insulator manufacturing process under zero waste or ideal conditions (scenario B). These results are used as a benchmark to compare environmental performance of electric disk insulator supply chain operating under actual conditions.

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843.
Orientia tsutsugamushi (Ott) is a causative agent of chigger‐borne zoonosis, scrub typhus which is life threatening and highly pervasive illness in humans. In this report, we have mined and classified the proteins involved in pathways unique to Ott by using high‐throughput computational techniques. The 12 metabolic pathways were found to be unique to the pathogen. Forty‐six proteins were reported to be essential for the pathogen's survival and non‐homologous to the humans. The proteins were categorized into different classes, ie, enzymes, transporters, DNA‐binding, secretory, and outer membrane proteins. Further, in silico analysis of 46 proteins showed that 25 proteins were suitable therapeutic targets with known druggable properties. The structural modeling of B3CSG3 (MurA) protein was carried out and catalytic site essential for its functioning was analyzed. Virtual screening of chemical compounds was performed against modeled structure. The docking study by AutodockVina reported compound from PubChem with CID: 16036947 as best and potential inhibitor by means of docking score and binding affinity. The reliability and stability of the MurA‐16036947 complex were confirmed with molecular dynamics simulation. The report will provide insight to understand the mechanism of pathogenesis of Ott and instigate the development of effective treatment strategies against this disease.  相似文献   
844.
Enterococcus faecalis is a gram‐positive, rod‐shape bacteria responsible for around 65% to 80% of all enterococcal nosocomial infections. It is multidrug resistant (MDR) bacterium resistant to most of the first‐line antibiotics. Due to the emergence of MDR strains, there is an urgent need to find novel targets to develop new antibacterial drugs against Efaecalis. In this regard, we have identified naphthoate synthase (1,4‐dihydroxy‐2‐naphthoyl‐CoA synthase, EC: 4.1.3.36; DHNS) as an anti‐E. faecalis target, as it is an essential enzyme for menaquinone (vitamin K2) synthetic pathway in the bacterium. Thus, inhibiting naphtholate synthase may consequently inhibit the bacteria's growth. In this regard, we report here cloning, expression, purification, and preliminary structural studies of naphthoate synthase along with in silico modeling, molecular dynamic simulation of the model and docking studies of naphthoate synthase with quercetin, a plant alkaloid. Biochemical studies have indicated quercetin, a plant flavonoid as the potential lead compound to inhibit catalytic activity of EfDHNS. Quercetin binding has also been validated by spectrofluorimetric studies in order to confirm the bindings of the ligand compound with EfDHNS at ultralow concentrations. Reported studies may provide a base for structure‐based drug development of antimicrobial compounds against Efaecalis.  相似文献   
845.
Present study assessed if semiochemical cues left by an aphidophagous beetle, M. sexmaculatus influenced foraging behaviour of a phytophagous beetle, Z. bicolorata on noxious weed, P. hysterophorus. The lower predation attributes of Z. bicolorata in presence of M. sexmaculatus semiochemical footprints confirms they interfere with weed biological control.  相似文献   
846.
Journal of Plant Biochemistry and Biotechnology - Vitamin E deficiency is a serious health concern in humans. Biofortification of maize kernel with high vitamin E (α-tocopherol) provides...  相似文献   
847.
Due to the extensive applications of vanillin as flavored compound and increasing consumers concern for its natural and environment friendly mode of production, present work was focused on the selection of bacterial isolate capable of producing vanillin using eugenol biotransformation. Bacterial strain SMS1003 is evidenced as the potential strain for vanillin production and identified as Bacillus safensis (GeneBank accession no. MG561863) using biochemical tests and molecular phylogenic analysis of its 16S rDNA gene sequence. Molar yield of vanillin reached up to 10.7% (0.055?g/L) at 96?h of biotransformation using growing culture of B. safensis SMS1003 in following culture conditions: eugenol concentration 500?mg/L; temperature 37?°C; initial pH 7.0; inoculum volume 4%; volume of culture media 10%; and shaking speed 180?rpm. Vanillin was detected as the single metabolite with a molar yield of 26% (0.12?g/L) at 96?h using resting cells of B. safensis SMS1003. Product confirmation was based on spectral scan using photodiode array detector, Fourier-transform infrared spectroscopy, high-performance liquid chromatography, and mass spectroscopy.  相似文献   
848.
Probiotics and Antimicrobial Proteins - The present study investigated skimmed milk and alginate-based encapsulation for protection of a probiotic strain, Lactobacillus gastricus BTM7 during...  相似文献   
849.
850.
There is extensive experimental data showing that the final pH and buffer composition after protein diafiltration (DF), particularly with monoclonal antibodies, can be considerably different than that in the DF buffer due to electrostatic interactions between the charged protein and the charged ions. Previous models for this behavior have focused on the final (equilibrium) partitioning and are unable to explain the complex pH and concentration profiles during the DF process. The objective of this study is to develop a new model for antibody DF based on solution of the transient mass balance equations, with the permeate concentrations of the charged species evaluated assuming Donnan equilibrium across the semipermeable membrane in combination with electroneutrality constraints. Model predictions are in excellent agreement with experimental data obtained during DF of both acidic and basic monoclonal antibodies, with the protein charge determined from independent electrophoretic mobility measurements. The model is able to predict the entire pH/histidine concentration profiles during DF, providing a framework for the development of DF processes that yield the desired antibody formulation.  相似文献   
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