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71.
Mitigation and adaptation synergy in forest sector 总被引:1,自引:1,他引:1
N. H. Ravindranath 《Mitigation and Adaptation Strategies for Global Change》2007,12(5):843-853
Mitigation and adaptation are the two main strategies to address climate change. Mitigation and adaptation have been considered
separately in the global negotiations as well as literature. There is a realization on the need to explore and promote synergy
between mitigation and adaptation while addressing climate change. In this paper, an attempt is made to explore the synergy
between mitigation and adaptation by considering forest sector, which on the one hand is projected to be adversely impacted
under the projected climate change scenarios and on the other provide opportunities to mitigate climate change. Thus, the
potential and need for incorporating adaptation strategies and practices in mitigation projects is presented with a few examples.
Firstly, there is a need to ensure that mitigation programs or projects do not increase the vulnerability of forest ecosystems
and plantations. Secondly, several adaptation practices could be incorporated into mitigation projects to reduce vulnerability.
Further, many of the mitigation projects indeed reduce vulnerability and promote adaptation, for example; forest and biodiversity
conservation, protected area management and sustainable forestry. Also, many adaptation options such as urban forestry, soil
and water conservation and drought resistant varieties also contribute to mitigation of climate change. Thus, there is need
for research and field demonstration of synergy between mitigation and adaptation, so that the cost of addressing climate
change impacts can be reduced and co-benefits increased. 相似文献
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75.
Multiple placental passes during chorionic villus sampling (CVS) increase the risk of fetal loss; however, specific factors that predispose to repeat aspiration have not been delineated. To identify anatomic and technical variables associated with multiple-pass procedures, a detailed review of 205 videotaped CVS procedures (single pass = 163; multiple pass = 42) was performed, blinded to pregnancy outcome. The route of sampling did not influence the need for multiple aspiration attempts (transabdominal—30/ 135; transcervical—12/70), nor was placental location alone discriminatory. However, the combination of a posterior placenta and uterine retroversion was observed more frequently in the multiple-pass cohort (8/42 vs. 9/163; p<0.05). In transabdominal cases, suboptimal needle placement (e.g., perpendicular to the placental long axis) was more common in the initial aspiration of a multiple-pass procedure (21/30 vs. 38/105;p<0.01), while limited penetration of the catheter tip (e.g., just inside the placental edge) characterized a majority of multiple-pass cases in the transcervical subset (7/12 vs. 3/58; p<0.0001). A case-control cohort was constructed to evaluate the impact of these technical variables on sampling efficacy, independent of the influence of uterine position and placental site. In that analysis, suboptimal location and/or orientation of the sampling device remained characteristic of multiple-pass cases. We conclude that further reduction in the frequency of multiple-pass procedures might be achieved by consistent placement of the device tip in the central placental mass. Unlike amniocentesis, where any point of amnion entry will suffice, this technical nuance should be emphasized with CVS to maximize the single-pass success rate. 相似文献
76.
A case is described of the prenatal diagnosis of choroid plexus cysts at 17 weeks' gestation which persisted beyond 36 weeks but could not be detected after delivery. At birth the child was found to have trisomy 18. 相似文献
77.
Stanislav N. Gorb 《Die Naturwissenschaften》1999,86(11):552-555
Two main types of joints occur in the damselfly wing: mobile and immobile. Some longitudinal veins (RP2–, RP3&4–, and MP–) are elastically joined with cross veins, whereas other longitudinal veins (IR1+, IR2+, MA+, CuA'+) are firmly joined with cross veins. In this study we mapped the distribution of serial elastic elements in the wing. The
occurrence of resilin, a rubberlike protein, in mobile joints suggests that the automatic twisting mechanism of the leading
edge by aerodynamic force works not by flexibility but by the elasticity of these joints. First, it should result in elastic
energy storage in the distal areas of the wing. Second, serial elastic elements of wing presumably act as dampers of an aerodynamic
force, which are responsible for gradual twisting of the leading edge.
Received: 16 March 1999 / Accepted in revised form: 26 August 1999 相似文献
78.
Citrullinaemia was presumed to be excluded in a fetus at risk by the direct assay of argininosuccinate synthetase in chorionic villi. The diagnosis was confirmed after amniocentesis by normal argininosuccinate synthetase activity in the cultured amniotic fluid cells and by a normal citrulline concentration in the amniotic fluid. The prediction of a normal fetus was confirmed at term by the birth of a non-citrullinaemic boy. 相似文献
79.
Paul Katzenberger 《Die Naturwissenschaften》1975,62(12):555-564
Works in the natural sciences are provided with comparatively less copyright protection than literary works. Nevertheless, this protection is important- for scientists. However, more recently, modern methods and techniques of information and documentation, such as reprography, microfilm archives, electronic data storage and retrieval, and data transmission have questioned the justification and effectiveness, even in principle, of this protection. A more detailed analysis demonstrates that this involves not so much a crisis of copyright law as a crisis of the entire field of scientific information. 相似文献
80.