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B. Sikkema-Raddatz R. H. Sijmons M. B. Tan-Sindhunata A. Y. Van Der Veen R. Brunsting B. De Vries J. R. Beekhuis D. J. Bekedam B. Van Aken B. De Jong 《黑龙江环境通报》1995,15(5):467-473
We report two cases of apparently balanced complex de novo chromosomal rearrangements (BCCR) detected prenatally at 17 weeks and 10 weeks of gestation, respectively. Chromosomes were studied using GTG-banding and fluorescent in situ hybridization (FISH). In one case four chromosomes and in the other case three chromosomes were involved in the rearrangements. One of the pregnancies was terminated and no external or internal abnormalities were detected at autopsy. The other pregnancy continued to term. Level III ultrasound examination showed no abnormalities. The child is now 3 years old and has neither congenital anomalies nor evidence of delayed psychomotor development. 相似文献
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Climate change has recently become a major focus for industry and government agencies. Some recent works have been reported on the use of pinch analysis techniques for carbon-constrained energy planning problems. This paper discusses a new application of graphical technique based on pinch analysis for company-level visualization and analysis of carbon footprint improvement. The technique is based on the decomposition of total carbon footprint into material- and energy-based components, or alternatively, into internal and external components. The decomposition facilitates the evaluation and screening of process improvement alternatives. Two industrial case studies on the production of phytochemical extracts and bulk chemicals are used to illustrate the new extension. 相似文献
116.
A juvenile lizard specimen with well-preserved skin impressions from the Upper Jurassic/Lower Cretaceous of Daohugou, Inner Mongolia, China 总被引:1,自引:0,他引:1
Lizards are now relatively well known from the Yixian Formation of northeastern China. In this study, we describe a juvenile
lizard from a fossil horizon at Daohugou, Inner Mongolia. These beds predate the Yixian Formation, and are probably Late Jurassic
or earliest Cretaceous in age. The new specimen thus documents the first lizard material from the Daohugou locality and is
the earliest lizard skeleton from China. Comparisons with developmental stages of modern lizards suggest the Daohugou lizard
is a hatchling. Although tiny, the specimen is notable in preserving exquisite skin impressions showing the variation in scalation
across the body, the shape and position of the cloacal outlet, and details of the manus and pes. These are the earliest recorded
lepidosaurian skin traces. In its general proportions and the possession of paired frontals, the small Daohugou lizard resembles
both the Yixian taxon Yabeinosaurus tenuis and the questionable Jeholacerta formosa, but it differs from the latter in scalation and, based on other characters, may be distinct from both. 相似文献
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Building regional priorities in forests for development and adaptation to climate change in the Congo Basin 总被引:1,自引:0,他引:1
Denis J. Sonwa Johnson N. Nkem Monica E. Idinoba Mekou Y. Bele Cyprain Jum 《Mitigation and Adaptation Strategies for Global Change》2012,17(4):441-450
Indentifying common priorities in shared natural resource systems constitutes an important platform for implementing adaptation
and a major step in sharing a common responsibility in addressing climate change. Predominated by discourses on REDD + (Reduced
Emissions from Deforestation and Forest Degradation and conservation, sustainable management of forests and enhancement of
forest carbon stocks in developing countries) with little emphasis on adaptation there is a risk of lack of policy measures
in addressing climate change in the Congo Basin. Forest products and ecosystem services provide security portfolios for the
predominantly rural communities, and play major roles in national development programmes in both revenue and employment opportunities.
Thus, raising the profile of forests in the policy arena especially in the twin roles of addressing climate change in mitigation
and adaptation and achieving resilient development is crucial. Within the framework of the Congo Basin Forests and Climate
Change Adaptation project (COFCCA) project, science policy dialogue was conducted to identify and prioritize forest based
sectors vulnerable to climate change but important to household livelihoods and national development. The goal of the prioritization
process was for the development of intervention in forest as measures for climate change adaptation in Central Africa. Participants
constituted a wide range of stakeholders (government, Non Governmental Organizations, research institutions, universities,
community leaders, private sectors etc.) as representatives from three countries directly involved in the project: Cameroon,
Central African Republic and Democratic Republic of Congo. Building on national priorities, four forest related sectors were
identified as common priorities at the regional level for focus on climate change adaptation. These sectors included: (1)
energy with emphasis on fuel wood and Charcoal; (2) Water principally quality, quantity, accessibility, etc.; (3) Food with emphasis on Non Timber Forest Products, and (4) Health linked to healthcare products (medicinal plants). Using these prioritized sectors, the project focused on addressing the impacts of climate change on local communities and the development of adaptation strategies in the three pilot countries
of the Congo Basin region. The four sectors constitute the key for development in the region and equally considered as priority sectors in the poverty
reduction papers. Focused research on these sectors can help to inject the role of forests in national and local development
and their potentials contributions to climate change adaptation in national and public discourses. Mainstreaming forest for
climate change adaptation into national development planning is the key to improve policy coherence and effectiveness in forest
management in the region. 相似文献
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European scale application of atmospheric reactive nitrogen measurements in a low-cost approach to infer dry deposition fluxes 总被引:1,自引:0,他引:1
Y.S. Tang I. Simmons N. van Dijk C. Di Marco E. Nemitz U. Dmmgen K. Gilke V. Djuricic S. Vidic Z. Gliha D. Borovecki M. Mitosinkova J.E. Hanssen T.H. Uggerud M.J. Sanz P. Sanz J.V. Chorda C.R. Flechard Y. Fauvel M. Ferm C. Perrino M.A. Sutton 《Agriculture, ecosystems & environment》2009,133(3-4):183
A European scale network was established in 2006 as part of the NitroEurope Integrated Project to infer reactive nitrogen (Nr) dry deposition fluxes, based on low-cost sampling of gaseous and aerosol species and inferential modelling. The network provides monthly measurements of NH3, NH4+, HNO3 and NO3−, as well as SO2, SO42−, HCl, Cl− and base cations at 58 sites. Measurements are made with an established low-cost denuder methodology (DELTA) as a basis to: (1) examine temporal trends and spatial patterns across Europe, (2) improve and calibrate inferential modelling techniques to estimate exchange of Nr species, (3) provide best estimates of atmospheric dry N deposition, and (4) permit an analysis of net GHG exchange in relation to atmospheric and agricultural N inputs at the European scale. Responsibility for measurements is shared among seven European laboratories. An inter-comparison of the DELTA implementation by 6 laboratories at 4 test sites (Montelibretti, Italy; Braunschweig, Germany; Paterna, Spain and Auchencorth, UK) from July to October 2006 provided training for the laboratories and showed that good agreement was achieved in different climatic conditions (87% of laboratory site-means within 20% of the inter-laboratory median). Results obtained from the first year of measurements show substantial spatial variability in atmospheric Nr concentrations, illustrating the major local (NH3) and regional (HNO3, NO3−, and NH4+) differences in Nr concentrations. These results provide the basis to develop future estimates of site-based Nr dry deposition fluxes across Europe, and highlight the role of NH3, largely of agricultural origin, which was the largest single constituent and will dominate dry Nr fluxes at most sites. 相似文献