1,017 research outputs found
Das hethitische Phonem /xw/
No full textIn the Hittite phonological system there was a labialized velar fricative /xw/ beside the plain velar fricative /x/ parallel to the opposition between the velar stops /kw/ and /k/. The frequent syllable /xwa/ was spelled either hu-(u) or hu-wa. Evidence from the frequency of words with initial hu in the lexicon, from spelling variations and from ablaut alternations is presented to demonstrate the existence of /xw/. It is suggested that Hittite /xw/ regularly corresponds to the reflexes of *w in the non-Anatolian Indo-European languages
Effective tumor therapy with plasmid-encoded cytokines combined with in vivo electroporation
No full textPlasmids may have unique advantages as a gene delivery system. However, a major obstacle is the low in vivo transduction efficiency. In this study, an electroporation-based gene transduction approach was taken to study the effect of interleukin (IL)-2 or IL-12 gene transduction on the growth of experimental murine tumors. Significant intratumoral gene transduction was achieved by electroporation of tumors that had been injected with naked plasmids encoding reporter genes and cytokine genes (IL-2 and IL-12) under the control of a constitutive cytomegalovirus promoter. In addition, significant tumor growth delay could be achieved in a murine melanoma line B16,F10 with the cytokine genes. Most importantly, systemic transgene levels were negligible when compared with intratumoral adenovirus-mediated IL-12 gene delivery, which leads to significantly higher systemic cytokine levels, Therefore, naked plasmid- and in vivo electroporation-mediated cancer gene therapy may be therapeutically efficacious while maintaining low systemic toxicity
The D1-triangulation in simplicial variable dimension algorithms for computing solutions of nonlinear equations
No full textPreparation, quasi-static, and dynamic compressive mechanical properties of BMG-W energetic structural materials
No full textIn this paper, the Zr41.2Ti13.8Cu12.5Ni10Be22.5 amorphous alloy powder and the spherical W particles were used to prepare the BMG-xW (BMG=Bulk Metallic Glass, x = 10, 20, 30, 40, 50 vol%) energetic structural materials (ESMs) by spark plasma sintering. The research results on energy performance indicated that the Zr41.2Ti13.8Cu12.5Ni10Be22.5 alloy powder had excellent thermal reactivity, high combustion enthalpy and combustion integrity. The microstructure, quasi-static, and dynamic compressive mechanical properties of the BMG-xW ESMs were investigated. The quasi-static compression test showed that when the sintering temperature was 365 °C and above, the BMG-xW ESMs with the W content of 20 vol% to 50 vol% had similar fracture strengths and higher plastic deformation abilities than the BMG samples prepared under the same conditions. We have analyzed the plasticity enhancement mechanism of the BMG-xW ESMs. In addition, the failure modes of the BMG-xW ESMs were all shear fracture, which was conducive to exerting their shear self-sharpening. The Hopkinson compression bar test showed that the fracture strength and failure strain of the BMG-xW ESMs were greater than the Zr41.2Ti13.8Cu12.5Ni10Be22.5 BMG under dynamic compression at the same strain rate, and the higher the W content, the fracture strength and failure strain tended to increase. All samples showed obvious flame during dynamic compression. The larger the strain rate, the lower the W content, the shorter the ignition delay time, the faster the flame spreading speed and the longer the combustion time. The damage experiment confirmed that the BMG-xW ESMs had significantly superior damage performance than the Zr41.2Ti13.8Cu12.5Ni10Be22.5 BMG
Effects of single and mixed infections with wild type and genetically modified Helicoverpa armigera nucleopolyhedrovirus on movement behaviour of cotton bollworm larvae
No full textNaturally occurring insect viruses can modify the behaviour of infected insects and thereby modulate virus transmission. Modifications of the virus genome could alter these behavioural effects. We studied the distance moved and the position of virus-killed cadavers of fourth instars of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) infected with a wild-type genotype of H. armigera nucleopolyhedrovirus (HaSNPV) or with one of two recombinant genotypes of this virus on cotton plants. The behavioural effects of virus infection were examined both in larvae infected with a single virus genotype, and in larvae challenged with mixtures of the wild-type and one of the recombinant viruses. An egt-negative virus variant caused more rapid death and lower virus yield in fourth instars, but egt-deletion did not produce consistent behavioural effects over three experiments, two under controlled glasshouse conditions and one in field cages. A recombinant virus containing the AaIT-(Androctonus australis Hector) insect-selective toxin gene, which expresses a neurotoxin derived from a scorpion, caused faster death and cadavers were found lower down the plant than insects infected with unmodified virus. Larvae that died from mixed infections of the AaIT-expressing recombinant and the wild-type virus died at positions significantly lower, compared to infection with the pure wild-type viral strain. The results indicate that transmission of egt-negative variants of HaSNPV are likely to be affected by lower virus yield, but not by behavioural effects of egt gene deletion. By contrast, the AaIT recombinant will produce lower virus yields as well as modified behaviour, which together can contribute to reduced virus transmission under field conditions. In addition, larvae infected with both the wild-type virus and the toxin recombinant behaved as larvae infected with the toxin recombinant only, which might be a positive factor for the risk assessment of such toxin recombinants in the environment
Optical properties of GaN wurtzite quantum wires
No full textThe electronic structure and optical properties of freestanding GaN wurtzite quantum wires are studied in the framework of six-band effective-mass envelope function theory. It is found that the electron states are either twofold or fourfold degenerate. There is a dark exciton effect when the radius R of GaN wurtzite quantum wires is in the range of [0.7, 10.9] nm. The linear polarization factors are calculated in three cases, the quantum confinement effect (finite long wire), the dielectric effect and both effects (infinitely long wire). It is found that the linear polarization factor of a finite long wire whose length is much less than the electromagnetic wavelength decreases as R increases, is very close to unity (0.979) at R = I nm, and changes from a positive value to a negative value around R = 4.1 nm. The linear polarization factor of the dielectric effect is 0.934, independent of radius, as long as the radius remains much less than the electromagnetic wavelength. The result for the two effects shows that the quantum confinement effect gives a correction to the dielectric effect result. It is found that the linear polarization factor of very long (treated approximately as infinitely long) quantum wires is in the range of [0.8, 1]. The linear polarization factors of the quantum confinement effect of CdSe wurtzite quantum wires are calculated for comparison. In the CdSe case, the linear polarization factor of R = I nm is 0.857, in agreement with the experimental results (Hu et al 2001 Science 292 2060). This value is much smaller than unity, unlike 0.979 in the GaN case, mainly due to the big spin-orbit splitting energy Delta(so) of CdSe material with wurtzite structure
Study on the ions' behavior in an electron cyclotron resonance plasma
No full textThe energy, velocity, angle distribution of ions in magnetoactive electron cyclotron resonance plasma have been studied with a two-dimension hybrid mode. The dependence of these distribution functions versus position and pressure are discussed. Our simulation results are in good agreement with many experimental measurements. (C) 1997 American Institute of Physics
Design of triangular lattice photonic crystals using genetic algorithms
No full textGenetic Algorithms (GAs) were used to design triangular lattice photonic crystals with large absolute band-gap. Considering fabricating issues, the algorithms represented the unit cell with large pixels and took the largest absolute band-gap under the fifth band as the objective function. By integrating Fourier transform data storage mechanism, the algorithms ran efficiently and effectively and optimized a triangular lattice photonic crystal with scatters in the shape of 'dielectric-air rod'. It had a large absolute band gap with relative width (ratio of gap width to midgap) 23.8%
High level synthesis for loop-based BIST
No full textArea and test time are two major overheads encountered during data path high level synthesis for BIST. This paper presents an approach to behavioral synthesis for loop-based BIST. By taking into account the requirements of the BIST scheme during behavioral synthesis processes, an area optimal BIST solution can be obtained. This approach is based on the use of test resources reusability that results in a fewer number of registers being modified to be test registers. This is achieved by incorporating self-testability constraints during register assignment operations. Experimental results on benchmarks are presented to demonstrate the effectiveness of the approach.link_to_subscribed_fulltex
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