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1.

Purpose  

Authors of different sustainability journals, including authors of articles in past issues of the International Journal of Life Cycle Assessment have acknowledged the rising interest and the pressing need for a social and socio-economic life cycle assessment methodology and identified challenges in its development and implementation. Social life cycle assessment (LCA) allows identification of key issues, assessing, and telling the story of social conditions in the production, use, and disposal of products. In this article, the United Nations Environment Programme/The Society of Environmental Toxicology and Chemistry Guidelines for Social Life Cycle Assessment of Products will be presented.  相似文献   

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In 1991, the Nordic Council of Ministers initiated a project on LCA. The objectives of the project have been to develop a Code of Practise for LCA built on Nordic consensus, to provide industry and other practitioners with a set of guidelines for LCA, mainly in “key issue identification” LCAs and to influence the international discussion on the subject. The final phase of the project is now being finished, resulting in Guidelines for LCA, which arc presented here briefly. Important topics are system boundary setting, cutoff criteria, allocations, data quality and impact assessment methods.  相似文献   

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Goal, Scope and Background  

In recent years several different approaches towards Social Life Cycle Assessment (SLCA) have been developed. The purpose of this review is to compare these approaches in order to highlight methodological differences and general shortcomings. SLCA has several similarities with other social assessment tools, although, in order to limit the expanse of the review, only claims to address social impacts from an LCA-like framework are considered.  相似文献   

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Meta-analysis: the past, present and future   总被引:1,自引:0,他引:1  
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Chitosomes: past, present and future   总被引:4,自引:0,他引:4  
José Ruiz-Herrera's discovery that chitin microfibrils could be made by a fungal extract paved the way for elucidating the intracellular location of chitin synthetase. In collaboration with Charles Bracker, chitosomes were identified as the major reservoir of chitin synthetase in fungi. Unique in size, buoyant density, and membrane thickness, chitosomes were found in a wide range of fungi. Their reversible dissociation into 16S subunits is another unique property of chitosomes. These 16S subunits are the smallest molecular entities known to retain chitin synthetase activity. Further dissociation leads to complete loss of activity. From studies with secretory mutants, yeast researchers concluded that chitosomes were components of the endocytosis pathway. However, key structural and enzymatic characteristics argue in favor of the chitosome being poised for exocytotic delivery rather than endocytotic recycling. The chitosome represents the main vehicle for delivering chitin synthetase to the cell surface. An immediate challenge is to elucidate chitosome ontogeny and the role of proteins encoded by the reported chitin synthetase genes in the structure or function of chitosomes. The ultimate challenge would be to understand how the chitosome integrates with the cell surface to construct the organized microfibrillar skeleton of the fungal cell wall.  相似文献   

10.
Immunotherapy: past,present and future   总被引:15,自引:0,他引:15  
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11.
Molecular methods of taxonomy and phylogeny have changed the way in which life on earth is viewed; they have allowed us to transition from a eukaryote-centric (five-kingdoms) view of the planet to one that is peculiarly prokarote-centric, containing three kingdoms, two of which are prokaryotic unicells. These prokaryotes are distinguished from their eukaryotic counterparts by their toughness, tenacity and metabolic diversity. Realization of these features has, in many ways, changed the way we feel about life on earth, about the nature of life past and about the possibility of finding life elsewhere. In essence, the limits of life on this planet have expanded to such a degree that our thoughts of both past and future life have been altered. The abilities of prokaryotes to withstand many extreme conditions has led to the term extremophiles, used to describe the organisms that thrive under conditions thought just a few years ago, to be inconsistent with life. Perhaps the most extensive adaptation to extreme conditions, however, is represented by the ability of many bacteria to survive nutrient conditions not compatible with eukaryotic life. Prokaryotes have evolved to use nearly every redox couple that is in abundance on earth, filling the metabolic niches left behind by the oxygen-using, carbon-eating eukaryotes. This metabolic plasticity leads to a common feature in physically stratified environments of layered microbial communities, chemical indicators of the metabolic diversity of the prokaryotes. Such 'metabolic extremophily' forms a backdrop by which we can view the energy flow of life on this planet, think about what the evolutionary past of the planet might have been, and plan ways to look for life elsewhere, using the knowledge of energy flow on earth.  相似文献   

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On 12-15 May 2011, a diverse group of students, researchers and practitioners from across Canada and around the world met in Banff, Alberta, to discuss the many facets of biodiversity science at the 6th Annual Meeting of the Canadian Society for Ecology and Evolution.  相似文献   

14.
Ranavirus: past, present and future   总被引:1,自引:0,他引:1  
Emerging infectious diseases are a significant threat to global biodiversity. While historically overlooked, a group of iridoviruses in the genus Ranavirus has been responsible for die-offs in captive and wild amphibian, reptile and fish populations around the globe over the past two decades. In order to share contemporary information on ranaviruses and identify critical research directions, the First International Symposium on Ranaviruses was held in July 2011 in Minneapolis, MN, USA. Twenty-three scientists and veterinarians from nine countries examined the ecology and evolution of ranavirus-host interactions, potential reservoirs, transmission dynamics, as well as immunological and histopathological responses to infection. In addition, speakers discussed possible mechanisms for die-offs, and conservation strategies to control outbreaks.  相似文献   

15.
Plague: past, present, and future   总被引:2,自引:0,他引:2  
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Biodiversity: past, present, and future   总被引:2,自引:0,他引:2  
Data from the fossil record are used to illustrate biodiversity in the past and estimate modern biodiversity and loss. This data is used to compare current rates of extinction with past extinction events. Paleontologists are encouraged to use this data to understand the course and consequences of current losses and to share this knowledge with researchers interested in conservation and ecology.  相似文献   

17.
During the processes of human population dispersal around the world over the past 50 000-100 000 years, along with associated cultural evolution and inter-population contact and conflict, there have been several major transitions in the relationships of Homo sapiens with the natural world, animate and inanimate. Each of these transitions has resulted in the emergence of new or unfamiliar infectious diseases.The three great historical transitions since the initial advent of agriculture and livestock herding, from ca. 10 000 years ago, occurred when: (i) early agrarian-based settlements enabled sylvatic enzootic microbes to make contact with Homo sapiens; (ii) early Eurasian civilizations (such as the Greek and Roman empires, China and south Asia) came into military and commercial contact, ca. 3000-2000 years ago, swapping their dominant infections; and (iii) European expansionism, over the past five centuries, caused the transoceanic spread of often lethal infectious diseases. This latter transition is best known in relation to the conquest of the Americas by Spanish conquistadores, when the inadvertent spread of measles, smallpox and influenza devastated the Amerindian populations.Today, we are living through the fourth of these great transitional periods. The contemporary spread and increased lability of various infectious diseases, new and old, reflect the combined and increasingly widespread impacts of demographic, environmental, behavioural, technological and other rapid changes in human ecology. Modern clinical medicine has, via blood transfusion, organ transplantation, and the use of hypodermic syringes, created new opportunities for microbes. These have contributed to the rising iatrogenic problems of hepatitis C, HIV/AIDS and several other viral infections. Meanwhile, the injudicious use of antibiotics has been a rare instance of human action actually increasing 'biodiversity'.Another aspect of this fourth transition is that modern hyper-hygienic living restricts microbial exposure in early life. This, in the 1950s, may have contributed to an epidemic of more serious, disabling, poliomyelitis, affecting older children than those affected in earlier, more endemic decades. As with previous human-microbe transitions, a new equilibrial state may lie ahead. However, it certainly will not entail a world free of infectious diseases. Any mature, sustainable, human ecology must come to terms with both the need for, and the needs of, the microbial species that help to make up the interdependent system of life on Earth. Humans and microbes are not "at war"; rather, both parties are engaged in amoral, self-interested, coevolutionary struggle. We need to understand better, and therefore anticipate, the dynamics of that process.  相似文献   

18.
Conservation managers are in the unenviable position of trying to conserve and restore biodiversity, without having a definitive timeframe to restore it to. Currently, managers around the world focus on various timeframes from recent to historical, but without a definitive target, countless conservation problems arise. Managers need to determine what constitutes a native species, which species to reintroduce, whether selective breeding should be implemented to resurrect supposedly extinct organisms, targets on population levels, whether assisted migration should be employed when climate change alters the environmental envelope of a species surrounded by human-altered landscapes, and how to manage for stochasticity and evolutionary processes. Without having definitive goals to target, these issues are difficult/impossible to address. It is only by discussing these important issues that some consensus will be attained that allow us to stop responding to crises and start predicting the future of biodiversity and plan and respond accordingly.  相似文献   

19.
Pagel JM 《Cytotherapy》2008,10(1):13-20
For more than a decade, Ab conjugated to a radionuclide emitting particulate radiation has been used in the management of leukemia in an effort to deliver targeted doses of radiation to BM, spleen and other sites of disease, while sparing normal organs. This radioimmunotherapy (RIT) approach has been employed to achieve significant remissions in patients with AML, particularly when used at high doses of radioactivity in conjunction with myeloablation. This report focuses on the therapeutic aspects of radiolabeled Ab for leukemia. Clinical results from recent leukemia RIT studies are reviewed, with emphasis on approaches being evaluated to improve rates of response and survival. Discussion of pre-clinical studies are limited to those that offer insights into future directions for clinical RIT studies of leukemia.  相似文献   

20.
Bacterial metallothioneins (MTs) have been known since the mid-1980s. The only family known until recently was the BmtA family, exemplified by the zinc- and cadmium-binding SmtA from the cyanobacterium Synechococcus PCC 7942, for which a structure was determined in 2001. Only in 2008 was a second type of bacterial MT identified in mycobacteria, and the copper-binding gene product was called MymT. Many of the features of SmtA either have been unexpected or are otherwise “unusual”, for example the presence of a zinc finger fold and the kinetic inertness of one of the four zinc ions bound to the protein. The unpredictability of molecular properties of this protein exemplified the need for continued biophysical studies of novel proteins. Homologues for SmtA have been identified in a limited number of bacterial genomes from cyanobacteria, pseudomonads, alphaproteobacteria, gammaproteobacteria, and firmicutes. Except for the residues defining the zinc finger fold, these homologous protein sequences display an intriguing variety, especially in terms of metal ligand position and identity. The increased number of homologues has allowed use of hidden Markov models to look for more remote relatives of SmtA, leading to the identification of a novel family of putative hybrid LIM domain MTs. However, database searches based on sequence similarity are of limited use for mining for further “overlooked” bacterial MTs, as so far undiscovered bacterial MTs may be too diverse from any other known MTs, and other approaches are required.  相似文献   

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