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491.
Frans J. Los MD PhD Diane Van Opstal Martin P. Schol Johannes L. J. Gaillard Helen Brandenburg Ans M. W. Van Den Ouweland Peter A. In 'T Veld 《黑龙江环境通报》1995,15(12):1155-1159
A prenatally detected case of a rare mosaic tetrasomy 12p/trisomy 12p is reported, presenting as the well-known accessory isochromosome 12p and a supernumerary single 12p marker in 17/24 and 6/24 clones of cultured amniotic fluid cells, respectively. The chromosomal nature of both marker chromosomes was investigated in cultured amniotic fluid cells by fluorescent in situ hybridization with various probes: the 12-centromeric probes pa12H8 and D12Z3, a whole chromosome 12 paint, and the chromosome 12p-specific paint M28. DNA analysis revealed a maternal origin of the extra 12p material. After counselling, the parents requested termination of pregnancy. Inspection and autopsy of the fetus revealed many of the dysmorphisms and internal structural abnormalities of the Pallister–Killian syndrome. 相似文献
492.
Miscanthus for Renewable Energy Generation: European Union Experience and Projections for Illinois 总被引:1,自引:0,他引:1
Heaton Emily A. Long Stephen P. Voigt Thomas B. Jones Michael B. Clifton-Brown John 《Mitigation and Adaptation Strategies for Global Change》2004,9(4):433-451
Mitigation and Adaptation Strategies for Global Change - 相似文献
493.
Chemical process simulation (CPS) software has been widely used by chemical (process) engineers to design, test, optimise, and integrate process plants. It is expected that industrial ecologists to bring these same problem-solving benefits to the design and operation of industrial ecosystems can use CPS. This paper provides industrial ecology researchers and practitioners with an introduction to CPS and an overview of chemical engineering design principles. The paper highlights recent research showing that CPS can be used to model industrial ecosystems, and discusses the benefits of using CPS to address some of the technical challenges facing companies participating in an industrial ecosystem. CPS can be used to (i) quantitatively evaluate and compare the potential environmental and financial benefits of material and energy linkages; (ii) solve general design, retrofit, or operational problems; (iii) help to identify complex and often counter-intuitive solutions; and (iv) evaluate what-if scenarios. CPS should be a useful addition to the industrial ecology toolbox. 相似文献
494.
Carbon sequestration in the global carbon cycle is almost always attributed to organic carbon storage alone, while soil mineral carbon is generally neglected. However, due to the longer residence time of mineral carbon in soils (102–106 years), if stored in large quantities it represents a potentially more efficient sink. The aim of this study is to estimate the mineral carbon accumulation due to the tropical iroko tree (Milicia excelsa) in Ivory Coast. The iroko tree has the ability to accumulate mineral carbon as calcium carbonate (CaCO3) in ferralitic soils, where CaCO3 is not expected to precipitate. An estimate of this accumulation was made by titrating carbonate from two characteristic soil profiles in the iroko environment and by identifying calcium (Ca) sources. The system is considered as a net carbon sink because carbonate accumulation involves only atmospheric CO2 and Ca from Ca-carbonate-free sources. Around one ton of mineral carbon was found in and around an 80-year-old iroko stump, proving the existence of a mineral carbon sink related to the iroko ecosystem. Conservation of iroko trees and the many other biomineralizing plant species is crucial to the maintenance of this mineral carbon sink. 相似文献
495.
496.
M. M. P. B. Fuentes M. R. Fish J. A. Maynard 《Mitigation and Adaptation Strategies for Global Change》2012,17(1):51-63
Climate change poses a serious threat to sea turtles (Cheloniidae) as their terrestrial reproductive phase is only successful
within a limited range of environmental and physical conditions. These conditions are likely to become less optimal as climate
change progresses. To date, management and conservation of sea turtles has focused almost entirely on non-climatic stressors,
due at least in part to practitioners not knowing what strategies to take and the feasibility and risks of potential strategies.
To aid the management of sea turtles in a changing environment, we identified management strategies via a focus workshop and
surveys to mitigate the impacts of climate change to the terrestrial reproductive phase of sea turtles. The effectiveness,
ecological risks and potential social and logistical constraints associated with implementing each of the identified management
strategies is discussed. Twenty management strategies were identified; strategies varied from habitat protection to more active
and direct manipulation of nests and the nesting environment. Based on our results, we suggest a three-pronged approach to
sea turtle conservation in light of climate change, where managers and researchers should: 1) enhance sea turtle resilience
to climate change by mitigating other threats; 2) prioritise implementing the ‘no regret’ and ‘reversible’ management strategies
identified here; and 3) fill the knowledge gaps identified to aid the trial and implementation of the potential strategies identified here. By combining these three approaches our collective toolkit of sea turtle management strategies
will expand, giving us an array of viable approaches to implement as climate change impacts become more extreme. 相似文献
497.
Baselines for land-use change in the tropics: application to avoided deforestation projects 总被引:2,自引:0,他引:2
Sandra Brown Myrna Hall Ken Andrasko Fernando Ruiz Walter Marzoli Gabriela Guerrero Omar Masera Aaron Dushku Ben DeJong Joseph Cornell 《Mitigation and Adaptation Strategies for Global Change》2007,12(6):1001-1026
Although forest conservation activities, particularly in the tropics, offer significant potential for mitigating carbon (C)
emissions, these types of activities have faced obstacles in the policy arena caused by the difficulty in determining key
elements of the project cycle, particularly the baseline. A baseline for forest conservation has two main components: the
projected land-use change and the corresponding carbon stocks in applicable pools in vegetation and soil, with land-use change
being the most difficult to address analytically. In this paper we focus on developing and comparing three models, ranging
from relatively simple extrapolations of past trends in land use based on simple drivers such as population growth to more
complex extrapolations of past trends using spatially explicit models of land-use change driven by biophysical and socioeconomic
factors. The three models used for making baseline projections of tropical deforestation at the regional scale are: the Forest
Area Change (FAC) model, the Land Use and Carbon Sequestration (LUCS) model, and the Geographical Modeling (GEOMOD) model.
The models were used to project deforestation in six tropical regions that featured different ecological and socioeconomic
conditions, population dynamics, and uses of the land: (1) northern Belize; (2) Santa Cruz State, Bolivia; (3) Paraná State,
Brazil; (4) Campeche, Mexico; (5) Chiapas, Mexico; and (6) Michoacán, Mexico.
A comparison of all model outputs across all six regions shows that each model produced quite different deforestation baselines.
In general, the simplest FAC model, applied at the national administrative-unit scale, projected the highest amount of forest
loss (four out of six regions) and the LUCS model the least amount of loss (four out of five regions). Based on simulations
of GEOMOD, we found that readily observable physical and biological factors as well as distance to areas of past disturbance
were each about twice as important as either sociological/demographic or economic/infrastructure factors (less observable)
in explaining empirical land-use patterns.
We propose from the lessons learned, a methodology comprised of three main steps and six tasks can be used to begin developing
credible baselines. We also propose that the baselines be projected over a 10-year period because, although projections beyond
10 years are feasible, they are likely to be unrealistic for policy purposes. In the first step, an historic land-use change
and deforestation estimate is made by determining the analytic domain (size of the region relative to the size of proposed
project), obtaining historic data, analyzing candidate baseline drivers, and identifying three to four major drivers. In the
second step, a baseline of where deforestation is likely to occur–a potential land-use change (PLUC) map—is produced using
a spatial model such as GEOMOD that uses the key drivers from step one. Then rates of deforestation are projected over a 10-year
baseline period based on one of the three models. Using the PLUC maps, projected rates of deforestation, and carbon stock
estimates, baseline projections are developed that can be used for project GHG accounting and crediting purposes: The final
step proposes that, at agreed interval (e.g., about 10 years), the baseline assumptions about baseline drivers be re-assessed.
This step reviews the viability of the 10-year baseline in light of changes in one or more key baseline drivers (e.g., new
roads, new communities, new protected area, etc.). The potential land-use change map and estimates of rates of deforestation
could be re-done at the agreed interval, allowing the deforestation rates and changes in spatial drivers to be incorporated
into a defense of the existing baseline, or the derivation of a new baseline projection. 相似文献
498.
V. Sivakumar V. Ravi Verma P.G. Rao G. Swaminathan 《Journal of Cleaner Production》2007,15(18):1813-1818
Focus on eco-friendly processing techniques makes vegetable tanning a viable option in leather processing and establishes the subsequent need for the more efficient methods of extraction in tannin manufacture. Application of ultrasound has been tried in the extraction of tannins from myrobalan nuts in order to improve the extraction efficiency, to perform the extraction under milder process conditions and to reduce the process time. The influence of process parameters such as ultrasonic output power, time and temperature has been studied. Scale-up trials and the use of ultrasound in pulse mode have also been attempted. The results show that a three- to fivefold improvement is possible with ultrasonic output from 20 to 100 W. Extraction efficiency has been calculated from the maximum extractable materials from myrobalan nuts. Extraction efficiency is found to be 90% for ultrasound, 100 W without external heating as compared to 77% for control process at 70 °C for 4 h. Therefore, ultrasound could be employed even dispensing with provision for temperature controls. The use of ultrasound in pulse mode offered 70% extraction efficiency of continuous mode. Scale-up trials indicate that there exists an optimum ultrasonic output power depending on the amount of nuts used, to achieve better extraction efficiency. The effectiveness of ultrasonically extracted tannin solution has also been tested in the tanning process for its applicability. The degree of tanning efficacy has been assessed by shrinkage temperature measurement. The results indicate that ultrasonically extracted tannin solution is suitable for tanning process. Therefore, application of ultrasound in tannin extract manufacture is a viable option with added advantages. 相似文献
499.
500.
Jesús M. Avilés Deseada Parejo Tomás Pérez-Contreras Carlos Navarro Juan J. Soler 《Die Naturwissenschaften》2010,97(2):181-186
A considerable number of bird species carry feathers to their nests. Feathers’ presence in the nests has traditionally been explained by their insulating properties. Recently, however, it has been suggested that feathers carried to the nests by females of the spotted starling (Sturnus unicolor L.) could have an ornamental function based on their ultraviolet (300–400 nm) and human-visible longer wavelength (400–700 nm) coloration. In our population, 95.7% of feathers found inside next-boxes occupied by nesting starlings were rock dove fly feathers. Of these feathers, 82.7% were naturally positioned with their reverse side oriented toward the entrance hole and 42.4% of all found feathers were situated within the nest-cup. Here we experimentally assess the signaling function of ultraviolet coloration of feathers in nests of spotless starlings by providing nests with a number of pigeon flight feathers that were respectively treated on their obverse, reverse, both, or neither side with a UV blocker. Starlings placed 42.5% of the experimental feathers in the nest-cup irrespective of the UV block treatment. Orientation of feathers toward the entrance hole was not related with their ultraviolet radiation. However, feathers placed within the nest-cup were more likely found with their reverse side oriented toward the entrance hole confirming our correlative findings. These results suggest a minor role of ultraviolet coloration on feather location by spotless starlings. 相似文献