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1.
In India, about 0.86 million people is engaged in pulling cycle rickshaws as occupation. There is no anthropometric data of cycle rickshaw pullers although data is available for Indian population. The objective of the study was to collect anthropometric data of the cycle rickshaw pullers so that these could be utilized for redesigning a cycle rickshaw. Anthropometric data for 34 body measurements were recorded from 880 rickshaw pullers (age 18 to 66 years) of four different places in India. The mean values of different standing heights, different lengths and breadths of cycle rickshaw pullers were significantly lower compared with Indian population. However, there was no significant difference in erect sitting height. The outcome of the research project is beneficial for the manufacturers of cycle rickshaws and similar products well as users of such products, including rickshaw pullers. The manufacturers would be able to use the data for fabricating newer models of cycle rickshaws which would be more compatible for rickshaw pullers as well as passengers.  相似文献   

2.
细胞周期与细胞凋亡   总被引:9,自引:0,他引:9  
从海洋生物胚胎细胞到哺乳动物的细胞周期,主要是在其细胞周期基因产物周期素及P34的调控下启动,运行和脱出周期的;某些原癌基因或抑癌基因的产物如p53,pRB也直接调控着细胞周期。  相似文献   

3.
An increasing number of elements from the periodic table are being used in a growing number of products, enabling new material and product functionalities. Materials of high importance and high supply risks are usually referred to as critical materials. Many materials that are often considered critical are used in ways leading to their dissipative loss along the product life cycle. So far, the issue of material dissipation has been dealt with mainly on a rather aggregated level. Detailed knowledge on the occurrence and amount of dissipative losses in the life cycle of specific products is only scarcely available. Addressing this, a substance flow analysis of different critical metals along the life cycle of selected products is presented in this article. With regard to products used in Germany, the flows of indium and gallium used in copper‐indium‐gallium‐selenide (CIGS) photovoltaic cells, germanium used in polymerization catalysts, and yttrium used in thermal barrier coatings (TBCs) have been analyzed. The results comprise detailed knowledge about the life cycle stages in which dissipative losses occur and about the receiving media. In all case studies, a complete or almost complete dissipative loss can be observed, mainly to landfills and other material flows. In all case studies, material production can be identified as hotspots for dissipative losses. In two case studies fabrication and manufacturing (F&M for CIGS and TBCs) and in one case study end of life (polymerization catalysts) can be identified as further hotspots for dissipative losses. In addition, actions for reducing dissipation along the life cycle are discussed, targeting aspects such as the recovery of critical metals as by‐products, efficiency in F&M processes, and lack of recycling processes. Lack of economic incentives to apply more‐efficient technologies and processes already available is a key aspect in this regard.  相似文献   

4.
Insulation of buildings in order to save heating energy is an important technology for enabling sustainable development. This paper summarises the results of a comparative LCA study according to ISO 14040 standard series of HT stone wool, flax representing crop grown products and paper wool representing recycled products applied for roof insulation. As the three materials have vastly different lifecycles, yet fulfil the same function cycles, the methodology used should be of general interest. Part 1 consists of the project background, goal and scope definition, a detailed life cycle inventory analysis with sensitivity analysis, impact assessment and interpretation. The actual comparison of the results from the life cycle assessments of the three products, in which an attempt is made to answer the question of whether the biological products flax and paper wool are more environmentally preferable than the mineral product stone wool representing more traditional insulation materials, is discussed in Part 2.  相似文献   

5.
Sustainability assessment standards are currently being developed for a range of building products. This activity has been stimulated through the considerable success of the U.S. Green Building Council's (USGBC) LEED? standard. Transparent life cycle–based standards can guide manufacturers to design products that have reduced environmental impact. The use of a sustainability standard can certify performance and avoid green washing. In this article we present a logical framework for designing a sustainability assessment standard through the creation of tables that award points in the standard to be consistent with life cycle information. Certain minimum principles of consistency are articulated. In the case that the life cycle impact assessment method maps the life cycle inventory to impact through a linear weighting, two design approaches—impact category and activity substitution—are constructed to be consistent with these principles. The approach is illustrated in a case study of a partial redesign of a carpet sustainability assessment standard (NSF/ANSI‐140).  相似文献   

6.
Like the phosphatidyl inositol cycle, the sphingomyelin cycle produces a series of the secondary messengers transmitting extracellular signals from the cytoplasmic membrane into the nucleus. Sphingomyelin, ceramide, sphingosine, sphingomyelinase, and ceramidase are the main components of the sphingomyelin cycle. In spite of numerous data on the functional properties of sphingomyelin cycle products, the activation mechanism for the key enzyme of the sphingomyelin cycle, sphingomyelinase (SMase), is not well understood. We have discovered effects of both reduced (GSH) and oxidized (GSSG) glutathione on the activity of neutral SMase in animals. GSH administration (18 mg per mouse) inhibits this enzymatic activity in liver for 2 h and increases the sphingomyelin level exactly as occurs in cell culture. The levels of diene conjugates and ketodienes decrease simultaneously during the experiment, thus indicating the ability of GSH to suppress oxidative processes in the cell. GSSG administration (18 mg per mouse) has no effect on the SMase activity during the first 15 min, but increases it twofold after 1 h. A short-term decrease in this activity after 30 min may depend on the conversion of excess GSSG into its reduced form by glutathione reductase. Unlike GSH, GSSG has no effect on the level of ketodienes after 1 h, but it induces the accumulation of diene conjugates. A strong correlation exists between the changes in SMase activity and in the level of oxidation products caused by either GSH or GSSG. These data indicate a relationship between SMase activity and the level of peroxidation products and possibly a relation between two signaling systems: the sphingomyelin cycle and the oxidative system.  相似文献   

7.
Matsuno K 《Bio Systems》2012,109(2):159-168
The evolutionary onset of a reaction cycle such as an autocatalytic cycle requires a reliable framework for protecting the harbinger cycle, once it appears by any chance, against the hostile environments in the neighborhood. One natural candidate for protecting the fragile nascent cycle could be available from the operation of internal measurement envisioned in the relative-state formulation of quantum mechanics. Once every chemical reactant is taken to be relative to every other reactant in the act of measuring each other internally, the relative-state formulation provides the condition for favoring and protecting those events such that the reactions mediating between the reactants and the products may eventually form a reaction cycle.  相似文献   

8.
The tricarboxylic acid (TCA) cycle, otherwise known as the Krebs cycle, is a central metabolic pathway that performs the essential function of oxidizing nutrients to support cellular bioenergetics. More recently, it has become evident that TCA cycle behavior is dynamic, and products of the TCA cycle can be co-opted in cancer and other pathologic states. In this review, we revisit the TCA cycle, including its potential origins and the history of its discovery. We provide a detailed accounting of the requirements for sustained TCA cycle function and the critical regulatory nodes that can stimulate or constrain TCA cycle activity. We also discuss recent advances in our understanding of the flexibility of TCA cycle wiring and the increasingly appreciated heterogeneity in TCA cycle activity exhibited by mammalian cells. Deeper insight into how the TCA cycle can be differentially regulated and, consequently, configured in different contexts will shed light on how this pathway is primed to meet the requirements of distinct mammalian cell states.  相似文献   

9.
生命周期管理研究述评   总被引:3,自引:2,他引:3  
黄和平 《生态学报》2017,37(13):4587-4598
生命周期管理起源于生命周期思想,它是生命周期思想在实践中的具体应用,是面向可持续生产和消费,对产品、工艺和服务的全生命周期环境影响进行的综合管理,是解决复合生态系统中结构无序、效率不高和代谢冗余的有效途径,是基于生命周期评价原则与框架的一种环境管理手段或环境管理体系。全面回顾了生命周期管理的起源与内涵,阐述了生命周期管理与生命周期评价的区别与联系,梳理了生命周期管理与环境管理体系的关系。对生命周期管理在产品、企业、行业及城市等层次上的具体应用进行了总结与述评,并对其今后需深入研究的方向进行了展望。  相似文献   

10.
Summary Nonsense mutations have been isolated in cell division cycle genes in a strain of Saccharomyces cerevisiae that carries a temperature-sensitive amber suppressor. These mutants may be valuable in identifying the products of genes involved in the cycle and in determining the pattern of their synthesis during the cell cycle.  相似文献   

11.

Background, aim, and scope

Today, the effective integration of life cycle thinking into existing business routines is argued to be the most critical step for more sustainable business models. The study tests the suitability of an input–output life cycle assessment (IO-LCA) approach in screening life cycle impacts of energy-using products in companies. It estimates the life cycle impacts of three products and assesses the suitability of such approach in a company environment.

Materials and methods

The multiple case studies evaluate the suitability of an IO-LCA method in a company environment. A comprehensive life cycle cost and impact study of three product systems (building ventilation system, information and communication technology (ICT) network product, and welding machine) is conducted and the life cycle phases with highest economical and environmental contribution are determined. Scenario analysis is performed in order to assess the sensitivity of the results to major changes in the studied systems. Finally, the usability of the IO-LCA approach for environmental evaluations in companies is assessed by collecting data on workload and interviewing the participating workers and managers.

Results

The results showed that the use phase with operating energy was environmentally important in all evaluated energy-using products. However, only in one case (ICT network product) the use was the single most significant life cycle phase. In two other cases, the sourcing was equally important. The results also indicated that the IO-LCA approach is much easier to adapt by current management of companies because it automatically links life cycle costs to environmental indicators and, by order of magnitude, reduces the workload in companies.

Discussion

It appears that the IO-LCA approach can be used to screen environmentally significant life cycle phases of energy-using products in companies by utilizing readily available accounting or other documented data. The IO-LCA approach produced comparable results with the ones published in traditional process-based LCA literature. In addition to the main results, some practical benefits of using the IO-LCA could also be suggested: the approach was very fast to use and would thus allow an easier adoption of environmental evaluations in companies as well as wider environmental testing of products in early conceptual design phase.

Conclusions

The results indicated that the IO-LCA approach could clearly offer added value to the environmental management of companies. The IO-LCA was found to provide a very fast access to the key life cycle characteristics of products. Similarly, it offered practical means to integrate life cycle thinking into existing business routines and to activate the decision makers in companies by giving them easily comprehendible results.

Recommendations and perspectives

The results would suggest that similar environmental IO tables, besides the US ones used here, would have value and should be collected for other major geographical and economical regions. The tables would enable a much larger share of companies to manage their environmental issues. It also seems that, because the user profile is so dominant in the case of energy-using products, more studies, both theoretical (How to valuate the future behavior in environmental studies?) and empirical (What really creates value for users?), should focus on the behavior of users.
  相似文献   

12.
The developmental cycle of the obligate intracellular prokaryote Chlamydia trachomatis involves the serial alternation of two distinct morphological forms of the organism. To examine the basis of chlamydial differentiation we have searched for developmentally regulated gene products in this species. Chlamydia-infected cells were pulse-labelled with [35S] cysteine at various stages of development and the products of synthesis examined by SDS-PAGE. Our results indicate that the synthesis of the cysteine-rich outer-membrane proteins is developmentally regulated, occurring only late in the cycle during the conversion of reticulate bodies to elementary bodies. Both hydroxyurea and ampicillin block this conversion; as a result of this blockade the cysteine-rich outer-membrane proteins are not produced in the presence of either drug.  相似文献   

13.

Purpose  

There is an increasing interest in the assessment and comparison of the environmental impacts of consumer products. Schemes such as Grenelle de l’Environnement, currently under development in France, aim to assess and communicate the life cycle impacts of consumer products. Freshwater ecotoxicity is one of the impact categories under consideration. This paper presents the results of a comparison of USEtox and critical dilution volume (CDV) approaches for assessing laundry products.  相似文献   

14.
BACKGROUND: We coin two terms: First, chemical cytometry describes the use of high-sensitivity chemical analysis techniques to study single cells. Second, metabolic cytometry is a form of chemical cytometry that monitors a cascade of biosynthetic and biodegradation products generated in a single cell. In this paper, we describe the combination of metabolic cytometry with image cytometry to correlate oligosaccharide metabolic activity with cell cycle. We use this technique to measure DNA ploidy, the uptake of a fluorescent disaccharide, and the amount of metabolic products in a single cell. METHODS: A colon adenocarcinoma cell line (HT29) was incubated with a fluorescent disaccharide, which was taken up by the cells and converted into a series of biosynthetic and biodegradation products. The cells were also treated with YOYO-3 and Hoechst 33342. The YOYO-3 signal was used as a live-dead assay, while the Hoechst 33342 signal was used to estimate the ploidy of live cells by fluorescence image cytometry. After ploidy analysis, a cell was injected into a fused-silica capillary, where the cell was lysed. Fluorescent metabolic products were then separated by capillary electrophoresis and detected by laser-induced fluorescence. RESULTS: Substrate uptake measured with metabolic cytometry gave rise to results similar to those measured by use of laser scanning confocal microscopy. The DNA ploidy histogram obtained with our simple image cytometry technique was similar to that obtained using flow cytometry. The cells in the G(1) phase did not show any biosynthetic activity in respect to the substrate. Several groups of cells with unique biosynthetic patterns were distinguished within G(2)/M cells. CONCLUSIONS: This is the first report that combined metabolic and image cytometry to correlate formation of metabolic products with cell cycle. A complete enzymatic cascade is monitored on a cell-by-cell basis and correlated with cell cycle.  相似文献   

15.
The effects of orally administered secondary autoxidation products of linoleic acid in rat liver were investigated. Their administration led to two toxic effects on hepatic carbohydrate metabolism, as compared to the administration of saline or linoleic acid used as controls. One effect was depletion of glucose 6-phosphate and fructose 6-phosphate caused by the reduction of glycolysis and glycogenolysis, accompanied by decreases in glycogen synthesis and pentose phosphate cyclic activity. The reduction in these metabolic systems seems unlikely to occur because phosphofructokinase was regulated by ATP or citrate enzymatically, because their accumulation in the liver was not detected in the secondary products. Another toxic effect was the depletion of oxaloacetate and isocitrate caused by the reduction in enzyme activity of the mitochondrial citrate cycle. On the basis of these results, the hepatotoxic effects of secondary products are discussed as follows: the incorporated secondary products impaired the activities of hexokinase and phosphoglucomutase in the liver. The reduction in these enzyme activities resulted in the depletion of glucose 6-phosphate and fructose 6-phosphate, which led ultimately to decreases in the activities of phosphofructokinase, the pentose phosphate cycle, and glycogen synthesis. Moreover, the secondary products disturbed the mitochondrial membrane, resulting in a decrease in the activity of the citrate cycle, which was accompanied by depletion of its metabolites.  相似文献   

16.
Applications of information and communications technology (ICT) for the management of environmental data, if used during the design and at the end of the product life cycle, can improve the environmental performance of products. This specific application of ICT for data management is called product data technology (PDT) and is based on the use of international standards developed by ISO TC184/SC4. PDT enables the computerized representations of information about products, processes, and their properties that are independent of any proprietary computer system or software application. The standard product data models are designed to integrate the necessary information about materials used in the product, and such information can be accessed and used at any point in the life cycle, from design to disposal. In the article, we present how PDT can support life cycle assessment (LCA) by focusing on a series of standards for communicating data for design and manufacture and standards for business and commercial information. Examples of possibilities for using PDT and semantic web for LCA data are introduced. The findings presented here are based on DEPUIS (Design of Environmentally‐Friendly Products Using Information Standards), a project aimed at improving the eco‐design of new products and services through the innovative use of new information standards.  相似文献   

17.

Purpose

Sustainability of a material-based product mainly depends on the materials used for the product itself or during its lifetime. A material selection decision should not only capture the functional performance required but should also consider the economical, social, and environmental impacts originated during the product life cycle. There is a need to assess social impacts of materials along the full life cycle, not only to be able to address the “social dimension” in sustainable material selection but also for potentially improving the circumstances of affected stakeholders. This paper presents the method and a case study of social life cycle assessment (S-LCA) specialized for comparative studies. Although the authors’ focus is on material selection, the proposed methodology can be used for comparative assessment of products in general.

Methods

The method is based on UNEP/SETAC “guidelines for social life-cycle assessment of products” and includes four main phases: goal and scope definition, life cycle inventory analysis, life cycle impact assessment, and life cycle interpretation. However, some special features are presented to adjust the framework for materials comparison purpose. In life cycle inventory analysis phase, a hot spot assessment is carried out using material flow analysis and stakeholder and experts’ interviews. Based on the results of that, a pairwise comparison method is proposed for life cycle impact assessment applying analytic hierarchy process. A case study was conducted to perform a comparative assessment of the social and socio-economic impacts in life cycle of concrete and steel as building materials in Iran. For hot spot analysis, generic and national level data were gathered, and for impact assessment phase, site-specific data were used.

Result and discussion

The unique feature of the proposed method compared with other works in S-LCA is its specialty to materials and products comparison. This leads to some differences in methodological issues of S-LCA that are explained in the paper in detail. The case study results assert that “steel/iron” in the north of Iran generally has the better social performance than “concrete/cement.” However, steel is associated with many negative social effects in some subcategories, e.g., freedom of association, fair salary, and occupational health in extraction phase. Against, social profile of concrete and cement industry is damaged mainly due to the negative impact of cement production on safe and healthy living condition. The case study presented in this article shows that the evaluation of social impacts is possible, even if the assessment is always affected by subjective value systems.

Conclusions

Application of the UNEP/SETAC guidelines in comparative studies can be encouraged based on the results of this paper. It enables a hotspot assessment of the social and socio-economic impacts in life cycle of alternative materials. This research showed that the development of a specialized S-LCA approach for materials and products comparison is well underway although many challenges still persist. Particularly characterization method in life cycle impact assessment phase is challenging. The findings of this case study pointed out that social impacts are primarily connected to the conduct of companies and less with processes and materials in general. These findings confirm the results of Dreyer et al. (Int J Life Cycle Assess 11(2):88–97, 2006). The proposed approach aims not only to identify the best socially sustainable alternative but also to reveal product/process improvement potentials to facilitate companies to act socially compatible. It will be interesting to apply the UNEP/SETAC approach of S-LCA to other materials and products; materials with a more complex life cycle will be a special challenge. As with any new method, getting experience on data collection and evaluation, building a data base, integrating the method in software tools, and finding ways for effective communication of results are important steps until integrating S-LCA in routine decision support.  相似文献   

18.
Messenger RNA has been extracted from all stages of the life cycle of the parasitic multicellular helminth Schistosoma mansoni. In vitro translation of these mRNA preparations in rabbit reticulocyte lysates yielded in each case a large number of polypeptides. Immunoprecipitation of translation products either by serum from immune mice or from human patients demonstrated that relatively few, approximately 10, polypeptides are recognised as antigens. Two of the in vitro synthesised antigens, of mol. wts. 22 000 and 14 000, were demonstrated to correspond to schistosomula surface antigens. The expression of these antigens may show stage specificity. Both are readily detected from adult and sporocyst translation products, neither from schistosomula and only the 22 000 antigen from miracidia. This is an unexpected finding since similar polypeptide antigens occur on the surface of schistosomula. These results indicate that not only are schistosomula surface antigens preformed at the preceding sporocyst stage, i.e., within the snail host, but they also remain invariant throughout the life cycle in the vertebrate host. Two other prominent schistosomula surface antigens of mol. wts. 38 000 and 32 000, were not recognised amongst cell-free translation products directed by RNA from any life cycle stage. The demonstration that at least two schistosomula surface antigens are detectable amongst adult mRNA cell-free translation products demonstrates the feasibility of identifying the genes encoding them in cDNA libraries from adult worm mRNA.  相似文献   

19.
The International Journal of Life Cycle Assessment - Life cycle assessment (LCA) is considered a robust method to analyse the environmental impacts of products and is used in public and private...  相似文献   

20.
We report here the cloning of a human cell cycle gene capable of complementing a temperature-sensitive (ts) S-phase cell cycle mutation in a Chinese hamster cell line. Cloning was performed as follows. A human genomic library in phage lambda containing 600,000 phages was screened with labeled cDNA synthesized from an mRNA fraction enriched for the specific cell cycle gene message. Plaques containing DNA inserts which hybridized to the cDNA were picked, and their DNAs were assayed for transient complementation in DNA transformation experiments. The transient complementation assay we developed is suitable for most cell cycle genes and indeed for many genes whose products are required for cell proliferation. Of 845 phages screened, 1 contained an insert active in transient complementation of the ts cell cycle mutation. Introduction of this phage into the ts cell cycle mutant also gave rise to stable transformants which grew normally at the restrictive temperature for the ts mutant cells.  相似文献   

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