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1.
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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2.
Past applications of biosolids to soils at some locations added higher Cd levels than presently permitted. Cadmium phytoextraction would alleviate current land use constraints. Unamended farm soil, and biosolids amended farm and mine soils were obtained from a Fulton Co., IL biosolids management facility. Soils contained 0.16, 22.8, 45.3 mg Cd kg–1 and 43.1, 482, 812 mg Zn kg–1 respectively with initial pH 6.0, 6.1, 6.4. In greenhouse studies, Swiss chard (Beta vulgaris var. cicla), a Cd-accumulator maize (inbred B37 Zea mays) and a southern France Cd-hyperaccumulator genotype of Noccaea caerulescens were tested for Cd accumulation and phytoextraction. Soil pH was adjusted from ~5.5–7.0. Additionally 100 rice (Oryza sativa) genotypes and the Ni-hyperaccumulator Alyssum murale were screened for potential phytoextraction use.

Chard suffered phytotoxicity at low pH and accumulated up to 90 mg Cd kg–1 on the biosolids amended mine soil. The maize inbred accumulated up to 45 mg Cd kg–1 with only mild phytotoxicity symptoms during early growth at pH > 6.0. N. caerulescens did not exhibit phytotoxicity symptoms at any pH, and accumulated up to 235 mg Cd kg–1 in 3 months. Reharvested N. caerulescens accumulated up to 900 mg Cd kg–1 after 10 months. Neither Alyssum nor 90% of rice genotypes survived acceptably.

Both N. caerulescens and B37 maize show promise for Cd phytoextraction in IL and require field evaluation; both plants could be utilized for nearly continuous Cd removal. Other maize inbreds may offer higher Cd phytoextraction at lower pH, and mono-cross hybrids higher shoot biomass yields. Further, maize grown only for biomass Cd maximum removal could be double-cropped.  相似文献   

3.
Invasive weeds have threatened the integrity of ecosystems throughout the world. They affect not only the species diversity of native areas but also their biological integrity. In India, a number of invasive exotic weeds have been reported but some viz. Parthenium hysterophorus, Lantana camara and Ageratum conyzoides, especially those from tropical America are troublesome and have caused adverse ecological, economic and social impact. These weeds can be seen growing in different landscapes but are luxuriantly localized in unattended forests and cultivated areas. Parthenium hysterophorus (Asteraceae, commonly known as congress grass) is perhaps the most troublesome and noxious weed of urban and rural India. Besides rapidly colonizing areas replacing the native vegetation, it is also known to cause a number of human health problems such as skin allergy, rhinitis and irritation to eyes of the residents in the vicinity. Likewise, it causes fodder scarcity in addition to being unpalatable and toxic to livestock. Lantana camara (Verbenaceae), another serious tropical American pest, has encroached upon large areas of land, especially the forests where it has virtually replaced the forest floor vegetation and reduced tree growth. Also because of its bushy and spreading type of growth it obstructs forest operations. The third weed, Ageratum conyzoides (Asteraceae, Billy goat weed) has invaded agricultural fields. It interferes with crops and causes yield reductions of major staple crops of India. When it invades rangeland areas, it out competes native grasses causing scarcity of fodder. These weeds have similar growth strategies such as fast growth rates, short life-cycles, greater reproductive potential, high competitive abilities and allelopathy that make them successful invaders of native habitats. Mechanical, chemical, biological and cultural control tactics have failed individually, though integrated approaches combining all these approaches along with community participation and proper land management have been relatively successful. This paper presents various aspects of biology, ecology, hazards and control measures of these weeds.  相似文献   
4.
This paper presents a novel feature vector based on physicochemical property of amino acids for prediction protein structural classes. The proposed method is divided into three different stages. First, a discrete time series representation to protein sequences using physicochemical scale is provided. Later on, a wavelet-based time-series technique is proposed for extracting features from mapped amino acid sequence and a fixed length feature vector for classification is constructed. The proposed feature space summarizes the variance information of ten different biological properties of amino acids. Finally, an optimized support vector machine model is constructed for prediction of each protein structural class. The proposed approach is evaluated using leave-one-out cross-validation tests on two standard datasets. Comparison of our result with existing approaches shows that overall accuracy achieved by our approach is better than exiting methods.  相似文献   
5.
Designing protein sequences that can fold into a given structure is a well‐known inverse protein‐folding problem. One important characteristic to attain for a protein design program is the ability to recover wild‐type sequences given their native backbone structures. The highest average sequence identity accuracy achieved by current protein‐design programs in this problem is around 30%, achieved by our previous system, SPIN. SPIN is a program that predicts sequences compatible with a provided structure using a neural network with fragment‐based local and energy‐based nonlocal profiles. Our new model, SPIN2, uses a deep neural network and additional structural features to improve on SPIN. SPIN2 achieves over 34% in sequence recovery in 10‐fold cross‐validation and independent tests, a 4% improvement over the previous version. The sequence profiles generated from SPIN2 are expected to be useful for improving existing fold recognition and protein design techniques. SPIN2 is available at http://sparks-lab.org .  相似文献   
6.
Parkinson disease (PD) is the second leading neurodegenerative disease in the US. As there is no known cause or cure for PD, researchers continue to investigate disease mechanisms and potential new therapies in cell culture and in animal models of PD. In PD, one of the most profoundly affected neuronal populations is the tyrosine hydroxylase (TH)-expressing dopaminergic (DA) neurons of the substantia nigra pars compacta (SNpc). These DA-producing neurons undergo degeneration while neighboring DA-producing cells of the ventral tegmental area (VTA) are largely spared. To aid in these studies, The Michael J. Fox Foundation (MJFF) partnered with Thomas Jefferson University and Taconic Inc. to generate new transgenic rat lines carrying the human TH gene promoter driving EGFP using a 11 kb construct used previously to create a hTH-GFP mouse reporter line. Of the five rat founder lines that were generated, three exhibited high level specific GFP fluorescence in DA brain structures (ie. SN, VTA, striatum, olfactory bulb, hypothalamus). As with the hTH-GFP mouse, none of the rat lines exhibit reporter expression in adrenergic structures like the adrenal gland. Line 12141, with its high levels of GFP in adult DA brain structures and minimal ectopic GFP expression in non-DA structures, was characterized in detail. We show here that this line allows for anatomical visualization and microdissection of the rat midbrain into SNpc and/or VTA, enabling detailed analysis of midbrain DA neurons and axonal projections after toxin treatment in vivo. Moreover, we further show that embryonic SNpc and/or VTA neurons, enriched by microdissection or FACS, can be used in culture or transplant studies of PD. Thus, the hTH-GFP reporter rat should be a valuable tool for Parkinson''s disease research.  相似文献   
7.
Here, we describe the derivation of a novel human embryonic stem cell (hESC) line, Endeavour-2 (E-2), propagated on human fetal fibroblasts (HFF) in a serum-replacement media. The inner cell mass (ICM) was manually dissected from the blastocyst without using immunodissection and, therefore, antibodies from animal sources. A total of 20 embryos were thawed and cultured, eight embryos were hatched, and five ICMs were obtained. They were transferred onto HFF used as feeder layer, and one colony representing the initial cell proliferation of a new hESC line, E-2, was obtained. The newly emerged hESC colony was passaged first by physical dissection and subsequently by enzymatic dissociation. E-2 has been in culture for over 6 months and has been shown to possess typical features of a pluripotent hESC line including expression of stem cell surface markers (SSEA4, TRA-160, and integrin alpha-6), intracellular alkaline phosphatase, and pluripotency gene markers, OCT4 and NANOG. This hESC line shows lineage-specific differentiation into various representative cell types expressing markers characteristic of the three somatic germ layers under both in vitro and in vivo conditions. E-2 line shows a normal karyotype (46 XX) and has been successfully cryopreserved and thawed several times using slow-freezing procedures. E-2 adds to the repertoire of existing hESC lines for research and development purposes in the field of regenerative medicine.  相似文献   
8.
A series of 4-styrylcoumarin have been synthesized by Knoevenagel condensation between substituted 4-methylcoumarin-3-carbonitrile and different heterocyclic or aromatic aldehydes. 4-Methylcoumarin-3-carbonitrile has been synthesized by the base catalyzed reaction between substituted 2-hydroxyacetophenone and ethyl cyanoacetate. The structures of the newly synthesized compounds were confirmed by 1H NMR, IR and mass spectral analysis. All the compounds were evaluated for their anti-inflammatory activity (against TNF-α and IL-6) and anti-tubercular activity. Compounds 6a, 6h and 6j exhibited promising activity against IL-6 with 72-87% inhibition and compound 6v showed potent activity against TNF-α with 73% inhibition at 10 μM concentration. Whereas compounds 6n, 6o, 6r and 6u showed very good anti-tubercular activity against Mycobacterium tuberculosis H37Rv strain at <6.25 μM.  相似文献   
9.
One of the reasons for increased antibiotic resistance in Salmonella enterica serovar Typhi Ty2 is the influx of heavy metal ions in the sewage, from where the infection is transmitted. Therefore, curbing these selective agents could be one of the strategies to manage the emergence of multidrug resistance in the pathogen. As observed in our earlier study, the present study also confirmed the links between cadmium accumulation and antibiotic resistance in Salmonella. Therefore, the potential of a chemically-synthesised compound 2, 2′-dipyridyl diselane (DPDS) was explored to combat the metal-induced antibiotic resistance. Its metal chelating and antimicrobial properties were evidenced by fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM), and microbroth dilution method. Owing to these properties of DPDS, further, this compound was evaluated for its potential to be used in combination with conventional antibiotics. The data revealed effective synergism at much lower concentrations of both the agents. Thus, it is indicated from the study that the combination of these two agents at their lower effective doses might reduce the chances of emergence of antibiotic resistance, which can be ascribed to the multi-pronged action of the agents.  相似文献   
10.
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