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1.
For some years now, the Nederlandse Taalunie (Dutch Language Union) has been active in promoting the development of human language technology (HLT) applications for speakers of Dutch with communicative disabilities. The reason is that HLT products and services may enable them to improve their communication skills and verbal autonomy. We sought to identify a minimum common set of HLT resources that is required to develop tools for a wide range of communication disabilities. In order to reach this goal, we investigated the specific needs of communicatively disabled people and related these needs to the underlying HLT software components. By analysing the availability and quality of these essential HLT resources, we were able to identify which of the crucial elements need further research and development to become usable for developing applications for communicatively disabled speakers of Dutch. The results obtained in the current survey can be used to inform policy institutions on how they can stimulate the development of HLT resources for this target group. In the current survey results were obtained for Dutch, but a similar approach can also be applied to other languages.  相似文献   
2.
An electron-microscopical investigation of the morphology of equiatomic TiNi martensite has revealed at least two types of martensite: the twinned plate martensite and a wavy martensite. To our knowledge the latter has never been reported in the literature before. In a thin foil, the plate martensite can be transformed into the wavy martensite within a few weeks at ambient temperature or by temperature cycling between +100° C and liquid nitrogen temperature. The transformation into the wavy martensite has been studied dynamically with the aid of a video-recording system attached to the microscope. This revealed the step-wise migration of the irregular boundary between the wavy martensite and the high temperature phase. The transformation from the B2 phase to the wavy martensite is preceded by the formation of a superstructure having three times the lattice parameter of the CsCl (B2) structure. The transformation is very sensitive to the cooling rate during temperature cycling and can even be totally suppressed if the cooling rate is too high. The transformation characteristics are not affected by the thermal history of the sample.  相似文献   
3.
A male fetus is described with multiple congenital abnormalities including craniosynostosis and bilateral radial aplasia. There are many similarities to the case recently reported by Imaizumi and Kuroki (Am J Med Genet 41: 162-163). These cases may represent a new syndrome with overlapping features of the Baller-Gerold and Roberts syndromes.  相似文献   
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5.
Unsaturated fatty acids are usually hydrogenated with a nickel catalyst. As a side reaction, nickel dissolves in the fatty acids and forms nickel soaps. On refining the crude fatty acid feedstock by distillation, these nickel soaps are enriched in the bottom fraction (pitch) to a concentration range of 2,500–5,500 ppm. With a heat value comparable to heavy fuel oil, the pitch has been used as fuel. However, due to new environmental restrictions, the nickel concentration must be considerably reduced to limit gas emission of nickel. In this study, solvent extraction was investigated as a separation method for denickling of this valuable oleochemical by-product. At a temperature of 80°C, the nickel content in the pitch was reduced from 2,900 ppm to 4 ppm in three extraction steps by means of 1 wt% citric acid in water. Based on experimental results, a preliminary process flowsheet is presented consisting of extraction, stripping, acid washing and electrolysis. An economic analysis, performed on the extraction process and a process based on direct combustion followed by electrostatic precipitation revealed that direct combustion is economically more advantageous. However, the compatibility of the extraction alternative can be considerably improved by process optimization. The type and concentration of the stripping and acid washing agents, phase ratios, temperature, ionic strength and the equilibrium pH of the aqueous and acid phases are important process parameters that should be considered in the optimization process.  相似文献   
6.
A child with afibrinogenemia was evaluated for prophylactic cryoprecipitate transfusion due to recurrent episodes of traumatic bleeding. The parents would only consider ongoing transfusion therapy if a limited donor program could be established. Automated plasmapheresis was performed on a regular basis on the patient's parents and a limited number of selected donors. Studies on the initial units collected demonstrated that a single 500 mL plasmapheresis yielded a mean of 606 mg fibrinogen in the cryoprecipitate, which was stored in two bags. A total of 166 U of cryoprecipitate from 84 individual plasmapheresis donations were transfused prophylactically every 2-3 weeks over a 16-month period. Compared to transfusions from random donors, the use of a limited number of apheresis donors resulted in a donor exposure reduction of 87%. Clinically, the patient has had minimal bleeding during this period.  相似文献   
7.
More than 65% of IC failures are related to thermal and mechanical problems. For wafer backend processes, thermo-mechanical failure is one of the major bottlenecks. The ongoing technological trends like miniaturization, introduction of new materials, and function/product integration will increase the importance of thermomechanical reliability, as confirmed by the ITRS (International technology roadmap for semiconductors; [1]). Since most of the thermomechanical problems initiate in the design phase, failure prevention-designing for reliability, is strongly desired. To support wafer backend process development, it is necessary to develop reliable and efficient methodologies (both testing and modeling) to predict the thermal and mechanical behavior of backend processes.This paper presents our research results covering the backend process reliability modeling considering both thermal and mechanical (CMP) loading. The emphasis is particularly on the effect of using Cu/SiLK low-dielectric-constant (low-k) structure instead of the traditional Al/SiO2. SiLK is a particular polymeric low-k material developed by the Dow Chemical Company [2] [Adv. Mater. 12 (2002) 1767].Our results shows that Cu/SiLK structures exhibit significantly different reliability characteristics than their aluminum predecessors, and that they are more critical from several design aspects. This not only makes the stress management in the stacks more difficult, but also strongly impacts packaging.  相似文献   
8.
Beschreibung einer Versuchsanordnung zur Verfolgung von Umwandlungsvorgängen bei thermomechanischen Behandlungen durch Messung der Sättigungsinduktion. Mitteilung erster Versuchsergebnisse an legierten Stählen.  相似文献   
9.
Modulation of gene expression via nucleic acid sequence-specific intervention represents a new paradigm for drug discovery and development. Ribozymes are small RNA structures capable of cleaving RNA target molecules in a catalytic fashion. A 2'-O-allyl-modified hammerhead ribozyme designed to cleave the messenger RNA of cytochrome P-450 3A2 was administered to rats via 0.25 mg intravenous injections to investigate the disposition of this compound. The chemically modified ribozyme binds to serum albumin and can be displaced by phosphorothioate oligonucleotides. A biphasic plasma clearance with a distribution half-life of 12 min and an elimination half-life of 6.5 h was observed. A volume of distribution of 2.1 l/kg indicates perfusion into tissues well beyond the vascular system. The chemically modified ribozyme can be detected intact in the plasma up to 48 h after injection. Metabolic degradation of the chemically modified ribozyme occurs at unmodified ribonucleotides, leaving the 2'-O-allyl-modified sites intact. Recovery of intact chemically modified ribozyme was 1.9% of the administered dose at 12 h along with significant metabolites. The renal clearance of the intact ribozyme is an average 34.3 ml/h. The tissue distribution of the chemically modified ribozyme at 48 h is primarily to kidney and liver but the only detected material is a single 27-mer metabolite that has been cut in the unmodified GAAA region. The brain concentration of the prominent 27-mer metabolite is greater than that observed in the lung or spleen. Examination of tissues reveals no morphological evidence of toxicity. These data strongly support the potential utility of synthetic, 2'-O-allyl-modified hammerhead ribozymes as therapeutic agents in vivo.  相似文献   
10.
Units of 2-ureido-4-pyrimidone that dimerize strongly in a self-complementary array of four cooperative hydrogen bonds were used as the associating end group in reversible self-assembling polymer systems. The unidirectional design of the binding sites prevents uncontrolled multidirectional association or gelation. Linear polymers and reversible networks were formed from monomers with two and three binding sites, respectively. The thermal and environmental control over lifetime and bond strength makes many properties, such as viscosity, chain length, and composition, tunable in a way not accessible to traditional polymers. Hence, polymer networks with thermodynamically controlled architectures can be formed, for use in, for example, coatings and hot melts, where a reversible, strongly temperature-dependent rheology is highly advantageous.  相似文献   
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