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191.
Nicolae Peiu 《The International Journal of Life Cycle Assessment》2007,12(4):225-229
Aim, Scope and Background The paper proposes the assessment of the environmental interventions resulting from the electrical energy production in Romania,
a Central East European country, using the LCA technique limited to a Life Cycle Inventory study (an LCA without the Life
Cycle Impact Assessment phase).
Main Features The following life cycles of the energy carriers employed in the production of the electrical energy are analysed according
to their provenance: lignite (domestic) 31.2%, brown coal (domestic) 3.4%, brown coal (import) 0.4%, heavy oil (domestic,
land) 4.2%, heavy oil (domestic, continental platform of the Black Sea) 0.4%, heavy oil (import) 3.6%, natural gas (domestic)
12.4%, natural gas (import) 6.1%, hydropower 27.8%, and nuclear energy 10.5% from the total of the electrical energy produced
in Romania. The unit processes of the life cycles of these energy carriers are aggregated in two main stages: Pre-combustion
(extraction, processing, transport and achievement of infrastructure) and Combustion (the production of electricity). The
functional unit of the study is represented by 1 kwh. The spatial limits of the analysed system are extended as far as CIS
countries for coal, Western Siberia (Russian Federation) for natural gas and the OPEC countries for oil. The temporal limits
are included in the year 2000.
Results and Discussion The LCI study enabled us to quantify the interventions on the environment, which result from the electricity production in
Romania, the independent use of different energy carriers and the different life cycle stages of the system. The use of the
LCA technique in a prospective way shows the reduction of these interventions that could be achieved through the adoption
of specific scenarios for the development of electrical energy production in the country.
Conclusions The main findings of this Life Cycle Inventory study, the first for Romania, are: the emissions of pollutant substances are
prevailing in the combustion stage; for different energy carriers, the magnitude of environmental interventions decrease in
the following order: coal, oil, natural gas, hydropower and nuclear energy. By comparison with other countries, the environment
is more affected by the production of electricity in the case of Romania and only the promotion of alternative, renewable
resources such as hydropower could substantially improve these interventions.
Recommendations and Perspectives Some important interactions with the environment, like land use or the risks of the nuclear energy, are not taken into consideration
in the study because of the lack of particular data for Romania. We would like to continue the investigation in order to surpass
the limits of the study, on the one hand by collecting data concerning the risk of nuclear power or land use at the national
level for different energy carriers or, on the other hand, by taking into account some other renewable resources like wind
or solar energy. 相似文献
192.
The view of extracellular matrix (ECM) has evolved from a merely scaffolding and space filling tissue element to an interface
actively controlling cellular activities and tissue functions. A highly specialized form of ECM is the basement membrane (BM),
an ubiquitous sheet-like polymeric structure composed of a set of distinct glycoproteins and proteoglycans. In this review
we are largely focusing on function and assembly of BM in skin (1) at the dermo-epidermal interface and (2) in the resident
micro-vasculature. The role of the non-polymeric components perlecan and particularly nidogen is exemplified by reviewing
experiments based on genetic approaches and adequate experimental skin models in vivo and in vitro. While in mice total deficiency
of one of these components is eventually developmentally lethal, the severity of the defects varies drastically between tissues
and also the skin models recapitulating BM formation in vitro. There is accumulating evidence that this relies on the mechanical
properties, the molecular composition of the BM, the adjacent ECM or connective tissue, the dynamics of molecular assembly,
and ‘minor’ tissue-specific modifier or adapter components. Though the role of nidogen or perlecan is still remaining a controversial
issue, the statements ‘being essential for BM/or not’ should be consequently referred to the developmental, tissue, and functional
(e.g., repair) context. 相似文献
193.
Nicolae Hulpoi 《Archives of microbiology》1936,7(1-5):579-583
Zusammenfassung Mit Hilfe der Aufwuchsplattenmethode nach Cholodny läßt sich eine starke Mikroorganismenanhäufung in der Rhizosphäre der Pflanzen nachweisen. Teilweise handelt es sich um richtige Bakterienmäntel, die das Wurzelhaar umgeben. Unter Ergänzung durch Züchtungs- usw. Verfahren dürfte die Methode in dieser Richtung aussichtsreiche Möglichkeiten bieten.Im übrigen gab die Methode auf verschieden gedüngten Böden wenig faßbare Einblicke; doch dürfte auch hier eine Verbesserung der Methodik weiter führen. Die Mikroorganismenzahl ist in Freilandversuchen geringer als in Gefäßversuchen. In reichen Böden ist sie größer als in armen Böden; in jenen herrschten Stäbchen, Actinomyceten und Pilze vor, in diesen (Heidesand) waren fast nur Kokken zu beobachten. 相似文献
194.
195.
This paper argues that the practical reach and ethical impact of the One Health paradigm is conditional on satisfactorily distinguishing between interconnected and interdependent factors among human, non‐human, and environmental health. Interconnection does not entail interdependence. Offering examples of interconnections and interdependence in the context of existing One Health literature, we demonstrate that the conversations about One Health do not yet sufficiently differentiate between those concepts. They tend to either ignore such distinctions or embrace bioethically untenable positions. We conclude that careful conceptual differentiation can prevent One Health stakeholders either from over‐reaching or under‐reaching the practical and ethical boundaries of this developing paradigm. 相似文献