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101.
Several protein kinases have been shown to be involved in the regulation of cell growth and differentiation. Molecules, regulating the activity of these protein kinases, also effect the activity of certain transport systems. Genetic experiments, suggesting a similar connection between the regulation of cell growth and transport functions in MDCK cells, are discussed. 相似文献
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Chen Wenjun Chen Jing M. Price David T. Cihlar Josef Liu Jane 《Mitigation and Adaptation Strategies for Global Change》2000,5(2):143-169
Using an Integrated TerrestrialEcosystem C-budget model (InTEC), we simulated thecarbon (C) offset potentials of four alternativeforest management strategies in Canada: afforestation,reforestation, nitrogen (N) fertilization, andsubstitution of fossil fuel with wood, under differentclimatic and disturbance scenarios. C offset potentialis defined as additional C uptake by forest ecosystemsor reduced fossil C emissions when a strategy isimplemented to the theoretical maximum possibleextent. The simulations provided the followingestimated gains from management: (1) Afforesting allthe estimated 7.2 Mha of marginal agricultural landand urban areas in 1999 would create an average Coffset potential of 8 Tg C y-1 during 1999–2100,at a cost of 3.4 Tg fossil C emission in 1999. (2)Prompt reforestation of all forest lands disturbed inthe previous year during 1999–2100 would produce anaverage C offset potential of 57 Tg C y-1 forthis period, at a cost of 1.33 Tg C y-1. (3)Application of N fertilization (at the low rate of 5kg N ha-1 y-1) to the 125 Mha ofsemi-mature forest during 1999–2100 would create anaverage C offset of 58 Tg C y-1 for this period,at a cost of 0.24 Tg C y-1. (4) Increasingforest harvesting by 20% above current average ratesduring 1999–2100, and using the extra wood products tosubstitute for fossil energy would reduce averageemissions by 11 Tg C y-1, at a cost of 0.54 TgC y-1. If implemented to the maximum extent, thecombined C offset potential of all four strategieswould be 2–7 times the GHG emission reductionsprojected for the National Action Plan for ClimateChange (NAPCC) initiatives during 2000–2020, and anorder of magnitude larger than the projected increasein C uptake by Canada's agricultural soils due toimproved agricultural practices during 2000–2010. 相似文献
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M. R. Ulm MD K. Chalubinski C. Ulm B. Plöckinger J. Deutinger G. Bernaschek 《黑龙江环境通报》1995,15(4):368-372
Recently, sonography of the fetal face has gained increasing importance in prenatal diagnosis. It is not yet clear whether sonographic depiction of fetal tooth germs would have an influence on the prenatal diagnosis of ectodermal dysplasia syndromes. During routine malformation screening, horizontal sections of fetal jaws were visualized and examined for tooth germs in 124 pregnant women following sonographic ‘facing’. Histological jaw sections of fetuses that had died in utero at various gestational ages were produced in order to examine the degree of correspondence between the sonographic and histological findings. At least four tooth germs were found in the jaws of all fetuses between 19 and 34 gestational weeks (n=104). Although jaw visualization was possible between 14 and 18 gestational weeks (n=20), the exact number and location of the tooth germs could not be determined. Assessment of tooth germs may become increasingly important, as aplasia of the tooth germs is one of the principal signs of various hereditary ectodermal diseases. 相似文献
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Tuck Fatt Siew Thomas Aenis Joachim H. Spangenberg Alexandra Nauditt Petra Döll Sina K. Frank Lars Ribbe Beatriz Rodriguez-Labajos Christian Rumbaur Josef Settele Jue Wang 《Sustainability Science》2016,11(5):813-829
Transdisciplinary research (TDR) aims at identifying implementable solutions to difficult sustainability problems and at fostering social learning. It requires a well-managed collaboration among multidisciplinary scientists and multisectoral stakeholders. Performing TDR is challenging, particularly for foreign researchers working in countries with different institutional and socio-cultural conditions. There is a need to synthesize and share experience among researchers as well as practitioners regarding how TDR can be conducted under specific contexts. In this paper, we aim to evaluate and synthesize our unique experience in conducting TDR projects in Asia. We applied guiding principles of TDR to conduct a formative evaluation of four consortium projects on sustainable land and water management in China, the Philippines, and Vietnam. In all projects, local political conditions restricted the set of stakeholders that could be involved in the research processes. The set of involved stakeholders was also affected by the fact that stakeholders in most cases only participate if they belong to the personal network of the project leaders. Language barriers hampered effective communication between foreign researchers and stakeholders in all projects and thus knowledge integration. The TDR approach and its specific methods were adapted to respond to the specific cultural, social, and political conditions in the research areas, also with the aim to promote trust and interest of the stakeholders throughout the project. Additionally, various measures were implemented to promote collaboration among disciplinary scientists. Based on lessons learned, we provide specific recommendations for the design and implementation of TDR projects in particular in Asia. 相似文献
107.
Josef Cyrys Annette Peters Jens Soentgen H.-Erich Wichmann 《Journal of the Air & Waste Management Association (1995)》2014,64(4):481-487
In many European cities mass concentrations of PM10 (particles less than 10 μm in size) are still exceeding air quality standards as set by the European Commission in 1999. As a consequence, many cities introduced low emission zones (LEZs) to improve air quality and to meet the limit values. In Germany currently 48 LEZs are in operation. By means of dispersion modeling, PM10 concentrations were estimated to decrease up to 10%. Analysis of PM10 levels conducted for Cologne, Berlin, and Munich some time after the LEZs were introduced showed reduction of PM10 mass concentration in the estimated range. The PM10 particle fraction is, however, composed of particles with varying toxicity, of which diesel soot is highly health relevant. An evaluation of air quality data conducted in Berlin showed that in 2010 traffic-related soot concentrations measured along major roads decreased by 52% compared to 2007. Diesel particle emissions in Berlin were reduced in 2012 by 63% compared to a business-as-usual scenario (reference year 2007). A strong reduction of the traffic-related particle fraction of PM2.5 was also reported for Munich. Therefore, it is likely that the effects of LEZs are considerably more significant to human health than was anticipated when only considering the reduction of PM10 mass concentrations.
Implications: The implementation of low emission zones in German cities might result in a reduction of PM10 levels concentrations by up to 10%. However, it is difficult to show a reduction of PM10 annual averages in this order of magnitude as meteorology has a large impact on the year-to-year variation of PM mass concentrations. Monitoring of other PM metrics such as black smoke (BS) or elemental carbon (EC) might be a better strategy for evaluating LEZs effects. The benefit of low emission zones on human health is far greater than is presently visible from routine measurements of PM10. 相似文献
108.
The photocatalytical inactivation of bacteria (Escherichia coli, Staphylococcus epidermidis,...) in the flow‐through plate solar reactor by sunlight was investigated. The low stability of bacteria in the reactor was attributed to bacteria sensitivity to mixing and/or gas bubbling. Sunlight inactivation proceeds with sufficient rate even under cloudy conditions. 相似文献
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精神分析批评作为一种文学批评方法,可以用于解释作者的创作动机和研究文学文本。简要梳理精神分析批评的理论渊源,分析其对文学研究的影响,指出其缺陷,旨在帮助文艺批评者更好、更有效地运用于文学批评。 相似文献