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701.
702.
Nanotechnology has widespread application in agricultural, environmental and industrial sectors ranging from fabrication of molecular assemblies to microbial array chips. Despite the booming application of nanotechnology, there have been serious implications which are coming into light in the recent years within different environmental compartments, namely air, water and soil and its likely impact on the human health. Health and environmental effects of common metals and materials are well-known, however, when the metals and materials take the form of nanoparticles – consequential hazards based on shape and size are yet to be explored. The nanoparticles released from different nanomaterials used in our household and industrial commodities find their way through waste disposal routes into the wastewater treatment facilities and end up in wastewater sludge. Further escape of these nanoparticles into the effluent will contaminate the aquatic and soil environment. Hence, an understanding of the presence, behavior and impact of these nanoparticles in wastewater and wastewater sludge is necessary and timely. Despite the lack of sufficient literature, the present review attempts to link various compartmentalization aspects of the nanoparticles, their physical properties and toxicity in wastewater and wastewater sludge through simile drawn from other environmental streams.  相似文献   
703.
Late Quaternary extinctions and population fragmentations have severely disrupted animal‐plant interactions globally. Detection of disrupted interactions often relies on anachronistic plant characteristics, such as spines in the absence of large herbivores or large fruit without dispersers. However, obvious anachronisms are relatively uncommon, and it can be difficult to prove a direct link between the anachronism and a particular faunal taxon. Analysis of coprolites (fossil feces) provides a novel way of exposing lost interactions between animals (depositors) and consumed organisms. We analyzed ancient DNA to show that a coprolite from the South Island of New Zealand was deposited by the rare and threatened kakapo (Strigops habroptilus), a large, nocturnal, flightless parrot. When we analyzed the pollen and spore content of the coprolite, we found pollen from the cryptic root‐parasite Dactylanthus taylorii. The relatively high abundance (8.9% of total pollen and spores) of this zoophilous pollen type in the coprolite supports the hypothesis of a former direct feeding interaction between kakapo and D. taylorii. The ranges of both species have contracted substantially since human settlement, and their present distributions no longer overlap. Currently, the lesser short‐tailed bat (Mystacina tuberculata) is the only known native pollinator of D. taylorii, but our finding raises the possibility that birds, and other small fauna, could have once fed on and pollinated the plant. If confirmed, through experimental work and observations, this finding may inform conservation of the plant. For example, it may be possible to translocate D. taylorii to predator‐free offshore islands that lack bats but have thriving populations of endemic nectar‐feeding birds. The study of coprolites of rare or extinct taxonomic groups provides a unique way forward to expand existing knowledge of lost plant and animal interactions and to identify pollination and dispersal syndromes. This approach of linking paleobiology with neoecology offers significant untapped potential to help inform conservation and restoration plans. Un Eslabón Perdido entre un Loro No Volador y una Planta Parásita y el Papel Potencial de Coprolitos en Paleobiología de la Conservación  相似文献   
704.
Phytoremediation, the use of plants for in situ contaminant cleanup, is gaining new appreciation as an aesthetically pleasing, sustainable method that naturally makes use of solar power. Hybrid poplars are widely used because they grow rapidly and have high transpiration rates, making them advantageous for hydraulic control of groundwater. However, the tendency for trees and other vegetation to uptake metals may be a disadvantage in some settings due to potential redistribution of metals from groundwater to the ground surface. Therefore, a pilot test in the upper midwestern United States was implemented to evaluate the applicability of poplars to groundwater withdrawal and metals transport. © 2009 Wiley Periodicals, Inc.  相似文献   
705.
The recent intensification of human disturbances in the Caribbean has increased the prevalence of partial mortality on coral colonies. Partial mortality can change colony size by directly shrinking colonies or by splitting colonies into fragments. A reduction in colony size can also adversely affect fecundity and fitness as internal resources shift away from reproduction toward colony maintenance. This study aimed to determine whether three Caribbean coral species, Siderastrea siderea, Montastraea faveolata, and Diploria strigosa, along the reef tract in Puerto Morelos, Mexico (20o52′N, 86o51′W), continued to dedicate resources to reproduction when colonies were fragmented to pre-maturation size. Contrary to expectations, eggs were found in colonies that were smaller than the maturation size and had been subjected to partial mortality. The continued dedication of resources toward reproduction, even in the smallest colonies, suggests that resource trade-offs away from reproduction are not as rigid as previously suggested in stressed corals.  相似文献   
706.
Earthquakes are separated from other hazards in meaning, significance, and risk perception throughout the Islamic World due to their specific focus in their own chapter or surah “al-Zalzala” (99th) in the Qur'an. Unlike earthquakes that are discussed in terms or the Judgment Day or as divine punishment or retribution against the disbelieving or hypocritical—other natural hazards like floods, tornadoes, and landslides are rarely discussed. An extensive survey of earthquake survivors and longtime residents was undertaken to better understand the perceptions of seismic risk in Agadir, Morocco where two moderate earthquakes razed the city in 1960 leaving 15,000 dead and 25,000 injured. Most of the deaths were attributed to faulty construction (along with standards and enforcement), inaddition to poor evacuation plans.

During the summer of 2002, more than 250 earthquake survivors and residents were surveyed and interviewed for their knowledge and perception of the disaster forty years before. Surveys were conducted in Arabic, French and English and included questions and Likertscaled responses including extensive interviews in the hopes of obtaining ideas of their potential quake recurrence, seismology, current construction standard policies, and local and regional planning strategies. In addition, reviews the Qur'an, Hadith and classical and contemporary tafasir texts were used to investigate the guiding passages used in Islamic discussions of “al-Zalzala”.

It was found that younger persons (<25yo) were more likely to believed that brick, mortar and cement structures were always safer and stronger during and after a tremor, regardless as to whether they are iron-reinforced or sub-standard (and hazardous) stone or brick infilled. After the 1960 disaster, speedy recovery efforts often undermined concrete construction and reinforcement techniques since such ‘rebar’ was relatively unavailable. Even today, inferior and seismically unstable construction practices are widely used.

It was found that television-watchers considered themselves less knowledgeable about earthquakes, when in fact many aspects of the1960 event and earthquakes in general, were more widely understood by this group, supporting the notion that the medium of televisionis the most widely used, efficient, and fastest mass communication and education tool.

Less-educated respondents in general tended to attribute earthquakes to divine action and retribution. All questions, however, concerning the possibility of quake recurrence frequency or magnitude caused an overwhelming refusal to answer, or with the reply of ‘Allahu a'lam’ or “God is wisest”—implying or directly stating that any attempt at earthquake forecasting, quake-related construction, advanced architectural standards for seismic safety, and/or related education was ‘haram’ or prohibited by Islam.

Further discussions with participants in Agadir indicated that any guess, awareness or prediction was in fact, fortune-telling and therefore an act forbidden by the Qur'an and Hadith.

Finally, the less educated were more likely to say that Allah protected those who were devout and considered scientific assessment as futile, forecasting as forbidden, or new construction technologies as a waste since only the ‘kafir’ (non-Muslim) or ‘munafiq’ (hypocrite) were at risk to death or injury from an earthquake. These conclusions are important toward gaining an insight of perception and risky behavior in a questionably constructed city with now more than 600,000 people 40 years later, and in a region laced by active faulting.  相似文献   
707.
In loss estimation there is a spatial mismatch of hazard data that are commonly modeled on an explicit raster level and exposure data that are often available only for aggregated administrative units. Usually disaggregation methods that use ancillary information to distribute lumped exposure data in a finer spatial resolution help to bridge this gap. However, the actual influence of different mapping techniques and ancillary data on the final loss estimation has not been analyzed yet. In this paper three methods are applied to disaggregate residential building assets using two kinds of land use/land cover (LULC) data. The resulting disaggregated assets are validated and compared using census data of the residential building number on the community and constituency level. In addition, the disaggregated assets are taken to estimate residential building losses due to the flood in August 2002 in 21 municipalities on the River Mulde in Saxony, Germany. Losses are calculated with the help of four loss models. In general, disaggregation helps to decrease the error variance within the loss estimation. It must, however, be stated that the application of sophisticated disaggregation methods does not lead to significant improvements compared to the straightforward binary method. Therefore more effort should instead be put into the provision of high-resolution LULC data. Finally, the remaining uncertainties in loss estimation are high and demand further improvements in all modeling aspects.  相似文献   
708.
709.
Air pollutants in exhaust gas produced from LP-gas (propane) were studied using both laboratory engines and vehicles. The objective of the study was both to evaluate propane as a low-pollution fuel and to provide information on adjustment of engine parameters for advantageous use of propane as a low-pollution fuel. Variables in the study were air-fuel ratio (A/F), ignition timing schedule, and ambient temperature. Data comparable to that for propane relating A/F and ambient temperature to emissions are shown for natural gas and for gasoline.  相似文献   
710.
Individuals make decisions every day in group contexts which vary in size, structure, and purpose. The US Department of Defense (DoD) is a large organization composed of many groups, and like many organizations, it has a vested interest in improving the performance of its affiliated groups, especially as it concerns risk-informed decision-making. This article discusses current foibles and considerations for decision-making in DoD groups as identified through a workshop with experts in risk-informed decision-making, cognitive science, and military operations. Experts noted that terms associated with risk-informed decision-making were often misconstrued, that formal decision-making frameworks are underutilized, and that many considerations should be taken into account when attempting to improve decision-making performance.  相似文献   
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