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1.
Cyanobacterial populations detected on buildings by traditional methods are mainly filamentous, whereas direct microscopy shows that they are principally coccoid morphotypes that often cannot be isolated in culture, but may grow on artificial media when the spatial biofilm relationships are maintained. The polyphasic strategy described here was to select morphologically distinct colonies from rehydrated biofilms for direct DNA amplification, allowing uncultured organisms to be sequenced and their morphology to be characterized by microscopy. DNA data banks currently contain many entries for cyanobacteria of unrecorded morphology, which does not facilitate identification, although genetic variability in a population may be assessed. The sequence homologies of the present biofilm organisms (EMBL accession numbers AJ619681 to 619690) with those in DNA databanks were low, indicating differences between xerophytic cyanobacteria on walls and aquatic species comprising the majority in the databases. Further development of databases for the populations found in this environment, subject to temperature extremes, repeated desiccation and high UV and salt levels, is required.  相似文献   
2.
Vascular endothelial growth factor (VEGF) is the most important angiogenic mediator in ovarian hyperstimulation syndrome OHSS. Studies proved that cabergoline administration blocks the increase in vascular permeability via dephosphorylation of VEGF receptors and hence can be used as prophylactic agent against OHSS. This study aimed at evaluating the effectiveness of early administration of cabergoline in the prevention of OHSS in high risk cases prepared for ICSI. This case series study was conducted on 126 high risk patients prepared for ICSI using the fixed antagonist protocol. High risk patients were defined as having more than 20 follicles >12 mm in diameter, and/or E2 more than 3000 pg/ml when the size of the leading follicle is more than 15 mm. When the size of the leading follicle reached 15 mm, cabergoline was administered (0.5 mg/day) for 8 days. Patients were followed up clinically, ultrasonographically and hematologically. The final E2 was 6099.5 ± 2730 and the mean number of retrieved oocytes was 19.7 ± 7.8. The clinical pregnancy rate was 62/126 (49.2%). There were no significant changes (p > 0.05) comparing hematological parameters, renal function tests and liver function tests between the day of HCG and the day of blastocyst transfer. The incidence of severe OHSS in this group was 1/126 (0.9%), while moderate OHSS was 12 (9.5%) and there were no cases of critical OHSS. We concluded that early administration of cabergoline is a safe and potentially more effective approach for prophylaxis against OHSS in high risk cases.  相似文献   
3.
Life cycle thinking plays an important role in sustainable development in the building sector. However, the complexity of data collection and scope definition limits life cycle assessment (LCA) applications. Even if the inventory data have already been collected, tabulated, and indexed, the method is still time‐consuming, which may be discouraging for designers. This study demonstrates how the LCA of buildings can be robustly streamlined using structured underspecification of impact data combined with an effective and efficient triage of the data collection. Tests were conducted with a series of building typologies that were analyzed with a cradle‐to‐gate approach. The probabilistic triage approach was tested to identify selected activities requiring detailed specification because they contribute most to total impact, thereby reducing data gathering effort. Impacts such as global warming, acidification, eutrophication, and smog creation were assessed, and results showed that 40% to 46% of the bill of materials components represent 75% of total impacts of single‐family houses and multifamily buildings. By specifying only a prioritized subset of the bill of materials to the highest level of specificity, results proved to be reasonably accurate and obtainable with less effort.  相似文献   
4.
Most anthropogenic material stocks and flows are associated with the building sector. Several recent studies have developed material composition indicators (MCIs) suitable for calculating material stocks and flows of the building sector using bottom‐up approaches, which hold great potential to provide information to support resource efficiency policies. A major limitation is the lack of country‐specific MCIs. This study aims to introduce a concept for a better transferability of MCI across different contexts by proposing requirements for defining MCIs and to discuss options and limits of the transferability. We take existing MCIs for residential buildings in Germany and Japan as case studies and make them comparable by applying harmonization methods. Based on that, similarities and differences are systematically identified and discussed, considering their socioeconomic, cultural, technical, and environmental factors. Our results indicate significant limitations to the transferability of MCIs for detached houses, while bigger apartment complexes show greater homogeneity despite the very different environments in which they are constructed. This indicates that while it is possible to assume foreign MCIs as plausible for large constructions, local coefficients need to be estimated for smaller single‐family homes.  相似文献   
5.
This paper has outlined the areas of the Environment and Climate Programme (Economic and Social Aspects of Human Settlement) the BEQUEST project addresses. It has also examined the framework for analysis the project sets out for a common understanding of SUD and the assessment methods currently made use of by planners, architects, engineers and surveyors to build environmental capacity. The paper has done this by:
•  fore-grounding the question of urban development and representing the process of urbanisation as a life cycle of inter-related activities;
•  agreeing the sustainable development issues underlying the urban process;
•  identifying the environmental, economic and social structure, spatial level and time scales of sustainable urban development.
  相似文献   
6.
LCA of concrete and steel building frames   总被引:1,自引:0,他引:1  
The effects on the external environment of seven concrete and steel building frames representative of present-day building technology in Sweden were analysed using LCA methodology. Objects of the study included frame construction and supplementary materials. Several-storey offices and dwellings were studied. The functional unit was defined as one average m2 of floor area during the lifetime of the building. Inventory data were elaborated for concrete and steel production, the building site, service life, demolition and final disposal. Parameters included were raw material use, energy use, emissions to air, emissions to water and waste generation. The inventory results were presented and evaluated as such, in addition to an interpretation by using three quantitative impact assessment methods. Parameters that weighed heavily were use of fossil fuels, CO2, electricity, SOx 2 NOx 2 alloy materials and waste, depending on what assessment method was used. Over the life cycle, building production from cradle to gate accounted for about the same contribution to total environmental loads as maintenance and replacement of heat losses through external walls during service life, whereas demolition and final disposal accounted for a considerably lower contribution.  相似文献   
7.
8.
The potential impact of climate change by the year 2050 on intensive livestock systems in Britain is assessed through the use of simulation models of farming systems. The submodels comprise livestock feeding, livestock thermal balance and the thermal balance of controlled environment buildings and a stochastic weather generator. These are integrated to form system models for growing pigs and broiler chickens. They are applied to scenarios typical of SE England, which is the warmest region of the country and represents the worst case. For both species the frequency of severe heat stress is substantially increased, with a consequent risk of mortality. To offset this, it would be necessary to reduce stocking densities considerably, or to invest in improved ventilation or cooling equipment. Other effects on production are likely to be small.  相似文献   
9.
Mainly cyanobacteria, but also algae and fungi, were identified on the Jesuit missions San Ignacio Miní, Loreto, Santa María and Santa Ana, in NE Argentina. Many organisms were deeply pigmented, indicative of stressful conditions. San Ignacio samples of itacurú rock showed higher colonization and biodiversity, related to higher porosity allowing entry of water and nutrients. Sandstone from other locations was arenitous, containing 95% silicates. Physicochemical analyses suggested mobilization of ions, particularly Fe, from within the stone to the surface. This intense deteriorating colonization, together with climatic weathering, transforms the sandstone to a “protosoil,” for growth of bryophytes and higher plants.  相似文献   
10.
Longstanding demographic growth accompanied by rising settlement activities and development of industry led to an increasing demand on utilization of wood. Tree species were selected for their specific properties. As a consequence of regional differences of forest species composition, wood has become an extremely important trade commodity. Therefore, the utilization of individual species could substantially change in space and time. In this study, we use 8´135 precisely dated timber constructions from a dendrochronological database to investigate spatio-temporal changes in wood utilization across the Czech lands from the 15th to the 19th century. Our results suggest that the utilization of individual species in historical timber constructions was primarily limited by their availability. Species selection was also based on wood properties and stem geometry. Most of historical constructions (99.7%), represented mainly by roofs and ceilings, are made of fir, spruce, pine, and oak. While fir constructions prevail in eastern Moravia and Silesia, spruce constructions are largely spread across the western and central part of the Czech Republic. Pine and oak constructions reflect natural occurrence of such forests in lower elevated central Bohemia and southern Moravia. Although fir prevailed in timber construction in the late-Medieval and post-Medieval times, planting of spruce monocultures resulted in its significantly increased utilization by the end of the 19th century. This study demonstrates the value of dendrochronological databases as an indicator of historical wood utilization.  相似文献   
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