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61.
Purpose

Access, affordability and sustainability of raw material supply chains are crucial to the sustainable development of the European Union (EU) for both society and economy. The study investigates whether and how the social life cycle assessment (S-LCA) methodology can support responsible sourcing of raw materials in Europe. The potential of social indicators already available in an S-LCA database is tested for the development of new metrics to monitor social risks in raw material industries at EU policy level.

Methods

The Product Social Impact Life Cycle Assessment (PSILCA) database was identified as a data and indicators source to assess social risks in raw material industries in EU-28 and extra-EU countries. Six raw material country sectors in the scope of the European policy on raw materials were identified and aggregated among those available in PSILCA. The selection of indicators for the assessment was based on the RACER (Relevance, Acceptance, Credibility, Ease, Robustness) analysis, leading to the proposal of 9 social impact categories. An S-LCA of the selected raw material industries was, thus, performed for the EU-28 region, followed by a contribution analysis to detect direct and indirect impacts and investigate related supply chains. Finally, the social performance of raw material sectors in EU-28 was compared with that of six extra-EU countries.

Results and discussion

Considering the overall social risks in raw material industries, “Corruption”, “Fair salary”, “Health and safety” and “Freedom of association and collective bargaining” emerged as the most significant categories both in EU and extra-EU. EU-28 shows an above-average performance where the only exception is represented by the mining and quarrying sector. An investigation of the most contributing processes to social impact categories for EU-28 led to the identification of important risks originating in the supply chain and in extra-EU areas. Therefore, the S-LCA methodology confirmed the potential of a life cycle perspective to detect burdens shifting and trade-offs. However, only a limited view on the sectoral social performance could be obtained from the research due to a lack of social data.

Conclusions

The S-LCA methodology and indicators appear appropriate to perform an initial social sustainability screening, thus enabling the identification of hotspots in raw material supply chains and the prioritization of areas of action in EU policies. Further methodological developments in the S-LCA field are necessary to make the approach proposed in the paper fully adequate to support EU policies on raw materials.

  相似文献   
62.
Vegetation History and Archaeobotany - A system of farming with an alternation of land use between being cultivated or left fallow as grassland (Feldgraswirtschaft) developed in southwestern...  相似文献   
63.
The mammalian target of rapamycin complex 1 (mTORC1) integrates mitogenic and stress signals to control growth and metabolism. Activation of mTORC1 by amino acids and growth factors involves recruitment of the complex to the lysosomal membrane and is further supported by lysosome distribution to the cell periphery. Here, we show that translocation of lysosomes toward the cell periphery brings mTORC1 into proximity with focal adhesions (FAs). We demonstrate that FAs constitute discrete plasma membrane hubs mediating growth factor signaling and amino acid input into the cell. FAs, as well as the translocation of lysosome-bound mTORC1 to their vicinity, contribute to both peripheral and intracellular mTORC1 activity. Conversely, lysosomal distribution to the cell periphery is dispensable for the activation of mTORC1 constitutively targeted to FAs. This study advances our understanding of spatial mTORC1 regulation by demonstrating that the localization of mTORC1 to FAs is both necessary and sufficient for its activation by growth-promoting stimuli.  相似文献   
64.
Peptidoglycan is the major structural component of the Staphylococcus aureus cell wall, in which it maintains cellular integrity, is the interface with the host, and its synthesis is targeted by some of the most crucial antibiotics developed. Despite this importance, and the wealth of data from in vitro studies, we do not understand the structure and dynamics of peptidoglycan during infection. In this study we have developed methods to harvest bacteria from an active infection in order to purify cell walls for biochemical analysis ex vivo. Isolated ex vivo bacterial cells are smaller than those actively growing in vitro, with thickened cell walls and reduced peptidoglycan crosslinking, similar to that of stationary phase cells. These features suggested a role for specific peptidoglycan homeostatic mechanisms in disease. As S. aureus missing penicillin binding protein 4 (PBP4) has reduced peptidoglycan crosslinking in vitro its role during infection was established. Loss of PBP4 resulted in an increased recovery of S. aureus from the livers of infected mice, which coincided with enhanced fitness within murine and human macrophages. Thicker cell walls correlate with reduced activity of peptidoglycan hydrolases. S. aureus has a family of 4 putative glucosaminidases, that are collectively crucial for growth. Loss of the major enzyme SagB, led to attenuation during murine infection and reduced survival in human macrophages. However, loss of the other three enzymes Atl, SagA and ScaH resulted in clustering dependent attenuation, in a zebrafish embryo, but not a murine, model of infection. A combination of pbp4 and sagB deficiencies resulted in a restoration of parental virulence. Our results, demonstrate the importance of appropriate cell wall structure and dynamics during pathogenesis, providing new insight to the mechanisms of disease.  相似文献   
65.
Teylo  Luan  Arantes  Luciana  Sens  Pierre  Drummond  Lucia M. A. 《Cluster computing》2021,24(2):1051-1073
Cluster Computing - Cloud platforms usually offer several types of Virtual Machines (VMs) with different guarantees in terms of availability and volatility, provisioning the same resource through...  相似文献   
66.
ABSTRACT

To understand the mechanisms which enable the nucleus to function under low water potential, the morphology and biochemistry of potato cell nuclei were studied. Conformational modifications were observed in the chromatin of nuclei of cells growing under low water potential. These modifications include a higher number of heterochromatic centres, enlargement of the nuclear diameter, and a different accessibility of DNA to the action of restriction enzymes. Biochemical analyses showed that these chromatin modifications may coincide with quantitative and qualitative variations of several nuclear proteins, some of which may belong to the dehydrin family. We especially focussed our attention on a 45-kDa protein that is heat-stable and is recognised by an antibody raised against the conserved domain of dehydrins. The survival of potato cells in an environment where water availability is low may depend on several simultaneous events regarding the nucleus. The accumulation in the nucleus of specific proteins such as dehydrins could be required to stabilise the chromatin by means of their molecule-salvation action. Further studies are in progress to check whether or not variations in chromatin organisation may be one of the numerous traits that a cell must acquire to become water-stress resistant.  相似文献   
67.
Iron is released in a desferrioxamine (DFO)-chelatable form (DCI) when erythrocytes are challenged by an oxidative stress. In &#103 -thalassemic erythrocytes, both DCI content and release (after aerobic incubation for 24 h) are increased and correlated with the fetal hemoglobin (HbF) levels. Since erythrocytes from newborns have an extremely high content of HbF and are exposed to conditions of oxidative stress, the release of iron in these erythrocytes was investigated. The erythrocyte DCI content was increased in preterm but not in term newborns as compared to adults, while the release was increased in both preterm and term erythrocytes. The level of plasma non protein-bound iron (NPBI), which was not detectable in adults, was much higher in preterm than in term newborns. When term plus preterm newborns were divided in two groups, normoxic and hypoxic, according to cord blood pH, it was found that both iron release and NBPI were markedly higher in the hypoxic newborns compared to normoxic ones. Similar results were also obtained when the preterm and term infants were considered separately on the basis of cord blood pH. Therefore, iron release and NPBI are higher when conditions of hypoxia occur. In fact, when the values for iron release and NPBI were separately plotted against cord blood pH values, significant negative correlations were seen in both cases. NPBI was correlated with iron release seen in all the newborns and a significant part of the released iron could be recovered into the incubation medium at the end of the incubation.  相似文献   
68.
The higher risk of respiratory problem in infants delivered by elective caesarean section in comparison with vaginally born infants may be favoured by lower level of nitric oxide (NO) and carbon monoxide (CO) and higher oxidative stress in infants born by caesarean section. We studied healthy term infants born by vaginal delivery or by elective caesarean section. Nitric oxide, CO, guanosine 3–5 cyclic monophosphate, total hydroperoxide and advanced oxidation protein products (AOPP) were measured at birth and 48–72 h of life. Nitric oxide, CO and cGMP were lower at birth and at 48–72 h of life in infants born by elective caesarean delivery. Total hydroperoxide and AOPP levels were similar in the two groups and increased from birth to 48–72 h of life. In conclusion, nitric oxide and CO concentrations were higher in term infants vaginally born than in infants born by elective caesarean section and decreased from birth to 48–72 h of life. The mode of delivery did not affect the oxidative stress which increases from birth to 48–72 h of life.  相似文献   
69.
This paper studied the effect on UV-B ocular damage of 10µm hydrocaffeic acid (HCAF) alone and as a mixture (MIX) (5µm HCAF+5µm p-coumaric acid). Since ocular UV-B damage is mediated by reactive oxygen species, the aim was to test if HCAF and MIX could reduce oxidation damage in human conjunctival cells (WKD) in vitro and in cornea and sclera of rabbits in vivo. After UVB irradiation (44 J/m2) of WKD cells, 8-oxodG levels in DNA were markedly increased and this effect was attenuated by HCAF and MIX. Rabbit eyes were treated by application of HCAF and MIX drops before UV-B exposure (79 J/m2). Corneal and scleral DNA oxidation damage, xanthine-oxidase (XO) activity and malondialdehyde levels (MDA) in corneal tissue and prostaglandin E2 (PGE2) in the aqueous humour were reduced by HCAF alone and in combination with p-coumaric acid, showing their potential as a topical treatment against UV-B damage.  相似文献   
70.
Although phosphatidylinositol 5‐phosphate (PtdIns5P) is present in many cell types and its biogenesis is increased by diverse stimuli, its precise cellular function remains elusive. Here we show that PtdIns5P levels increase when cells are stimulated to move and we find PtdIns5P to promote cell migration in tissue culture and in a Drosophila in vivo model. First, class III phosphatidylinositol 3‐kinase, which produces PtdIns3P, was shown to be involved in migration of fibroblasts. In a cell migration screen for proteins containing PtdIns3P‐binding motifs, we identified the phosphoinositide 5‐kinase PIKfyve and the phosphoinositide 3‐phosphatase MTMR3, which together constitute a phosphoinositide loop that produces PtdIns5P via PtdIns(3,5)P2. The ability of PtdIns5P to stimulate cell migration was demonstrated directly with exogenous PtdIns5P and a PtdIns5P‐producing bacterial enzyme. Thus, the identified phosphoinositide loop defines a new role for PtdIns5P in cell migration.  相似文献   
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