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991.
Ecosystem service (ES) evidence and arguments can mobilize support for biodiversity conservation. However, the ES concept’s impact on the ground seems unclear: It is reliant upon a range of pre-requisites at the science-policy nexus and it tends to be science-driven and demanding in terms of data and required capacity. The TEEB stepwise approach (The Economics of Ecosystems and Biodiversity for Local and Regional Policy Makers, Earthscan, London, 2012) guides purpose-driven ES assessments and seeks to enhance the usefulness of the ES concept in difficult real-world settings. An application of this approach has not yet been appraised. Also, beyond the instrumental use of ES data (e.g. for the design of payment schemes for ES), there is little documented experience with strategically using ES arguments for mobilizing financial resources for conservation. As many other countries, Côte d’Ivoire does not have a strong knowledge base on ecosystem services (ES). Such circumstances can preclude the use of the ES concept for convincing potential donors to co-finance conservation. We examine the recent ES assessment for the Parc national de Taï (PNT), Côte d’Ivoire, which followed the TEEB stepwise approach. We look at process, results and outcomes to address three questions: (i) How did study results contribute to mobilizing funds for the PNT? (ii) In which ways was the TEEB stepwise approach useful in practice? (iii) What lessons can be drawn for ES assessments geared to conservation finance?  相似文献   
992.
The results of a 15 years investigation after the conversion from conventional to organic farming are presented for the beetle family Staphylinidae. The aim of the study was to find general trends in the succession of assemblages, changes in the biodiversity and changes of dispersion for invading or retreating species. The succession of all fields studied are shifted in the same direction, which indicates an overall driving ecological factor after the conversion. However, individual fields showed a different speed within the succession. The number of species remained on the same level in the first 8 years but increased from the eighth to the 15th year. However, the species diversity on the organic fields were still lower than in the field margins. The conventionally farmed fields in 2001 before the conversion of the main study area was compared with adjacent conventionally farmed fields investigated 15 years later. This comparison showed that the species diversity was currently much lower there than 15 years before in the main study area. During the succession single species retreated from fields after the conversion and other species invaded the fields. In particular, species of open habitats and inquilines of mammals invaded the fields. It was concluded that organic farming had benefit effects on biodiversity, but a mosaic with field margins will enhance this effect.  相似文献   
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The neutral glycosphingolipid fraction from adults of the pig parasitic nematode, Ascaris suum, was resolved into four components on thin-layer chromatography. The high-performance liquid chromatography-isolated components were structurally analysed by: methylation analysis; exoglycosidase cleavage; gas-liquid chromatography/mass spectrometry; liquid secondary-ion mass spectrometry; and, in particular, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Their chemical structures were determined as: Glc(β1-1)ceramide, Man(β1-4)Glc(β1-1)ceramide, GlcNAc(β1-3)Man(β1-4)Glc(β1-1)ceramide and Gal(α1-3)GalNAc(β1-4)GlcNAc(β1-3)Man(β1-4)Glc(β1-1)ceramide; and were characterized as belonging to the arthro-series of protostomial glycosphingolipids. No glycosphingolipid component corresponding to ceramide tetrasaccharide was detected during these analyses. The ceramide composition of the parent glycosphingolipids was dominated by the 2-(R)-hydroxy C24:0 fatty acid, cerebronic acid, and C17 sphingoid-bases: 15-methylhexadecasphing-4-enine and 15-methylhexadecaphinganine in approximately equal proportions. The component ceramide monohexoside was characterized by an additional 15-methylhexadecaphytosphingosine. Abbreviations: CDH, ceramide dihexoside; Cer, ceramide; CMH, ceramide monohexoside; CPH, ceramide pentahexoside; CTH, ceramide trihexoside; CTetH, ceramide tetrahexoside; Hex, hexose; HexNAc, N-acetylhexosamine; HPTLC, high-performance thin-layer chromatography; LSIMS, liquid secondary-ion mass spectrometry; MALDI-TOF-MS, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry; N-, Nz- and A-glyco(sphingo)lipids, neutral, neutralzwitterionic and acidic glyco(sphingo)lipids, respectively This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
999.
A reciprocal t(17;22)(q11.2;q11.2) was found in a female patient with neurofibromatosis type 1 (NF1) and in her affected daughter. Sequence analysis of cloned junction fragments traversing the breakpoints allowed the identification of the structures involved in the rearrangement. Aberrant bands in Southern hybridizations of restriction enzyme-digested DNA of the patient pointed to the disruption of the NF1 gene in intron 31. Semispecific polymerase chain reaction analysis of the genomic DNA of the patient with the specific primer anchored at NF1 exon 31 was used to obtain the breakpoint-spanning fragment of the derivative chromosome 17. The intron 31 sequence turned out to be interrupted within a large irregular (AT) repeat. The chromosome 22-derived sequence of the der(17) junction fragment allowed us to identify cosmids of the corresponding region from a chromosome 22-specific cosmid library. With the support of the breakpoint-spanning cosmids, the chromosome 22 region upstream of the fragment carried by the der(17) was characterized. Primers deduced from the sequence of this upstream region were used in combination with a primer in NF1 intron 31 distal to the breakpoint on chromosome 17 to amplify the der(22) junction fragment. The structure of the junction sequences suggested that the translocation had arisen by unequal homologous recombination between (AT)-rich repeats on chromosome 22 and on chromosome 17 in intron 31 of the NF1 gene. However, our data support the assumption of additional rearrangements prior to, or in the course of, the recombination event, leading to a loss of the sequences between the involved (AT) repeats on chromosome 22. In the direct vicinity of these (AT) repeats, two members of a previously undescribed low-copy repetitive sequence have been found, copies of which are also present on human chromosome 13. Received: 27 August 1996 / Revised: 7 October 1996  相似文献   
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Teratomas are benign tumors that form after ectopic injection of embryonic stem (ES) cells into mice and contain derivatives of all primitive germ layers. To study the role of β1 integrin during teratoma formation, we compared teratomas induced by normal and β1-null ES cells. Injection of normal ES cells gave rise to large teratomas. In contrast, β1-null ES cells either did not grow or formed small teratomas with an average weight of <5% of that of normal teratomas. Histological analysis of β1-null teratomas revealed the presence of various differentiated cells, however, a much lower number of host-derived stromal cells than in normal teratomas. Fibronectin, collagen I, and nidogen were expressed but, in contrast to normal teratomas, diffusely deposited in β1-null teratomas. Basement membranes were present but with irregular shape and detached from the cell surface.

Normal teratomas had large blood vessels with a smooth inner surface, containing both host- and ES cell–derived endothelial cells. In contrast, β1-null teratomas had small vessels that were loosely embedded into the connective tissue. Furthermore, endothelial cells were always of host-derived origin and formed blood vessels with an irregular inner surface. Although β1- deficient endothelial cells were absent in teratomas, β1-null ES cells could differentiate in vitro into endothelial cells. The formation of a complex vasculature, however, was significantly delayed and of poor quality in β1-null embryoid bodies. Moreover, while vascular endothelial growth factor induced proliferation of endothelial cells as well as an extensive branching of blood vessels in normal embryoid bodies, it had no effect in β1-null embryoid bodies.

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