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51.
Collaborative research and development (R&D) activities between public universities and industry are of importance for the sustainable development of the innovation ecosystem. However, policymakers especially in developing countries show little knowledge on the issues. In this paper, we analyse the level of university–industry collaboration in Malaysia. We further examine the fundamental conditions that hinder university–industry collaboration despite the government’s initiatives to improve such linkages. We show that the low collaboration  is a result of an R&D gap between the entities. While the universities engage in basic and fundamental R&D, the private sectors involved in incremental innovation that requires less R&D investments. The different nature of the industries’ R&D requires closer cooperation between firms namely buyers, suppliers and technical service providers and not the universities. Among others, the lack of an intermediary role, absorptive capacity and collaborative initiative by the industry also contribute to the problem. The study suggests that the collaborative activities can benefit both if deliberate and effective efforts on reducing the R&D mismatch are made between the universities and industry. Likewise, proper institutional arrangements in coordinating these activities are required. This result seems to reflect the nature of many developing countries’ national innovation systems, and therefore, lessons from Malaysia may serve as a good case study.  相似文献   
52.
Vanadium dioxide is popular for the metal-insulator phase transition at 68°C. Chemical doping is one of the effective ways adopted to tune the phase transition temperature, where tungsten is known to reduce the transition temperature of VO2. This work investigates the effect of tungsten doping on the mechanical properties of VO2 microcrystals and their polymer composites. Doping of VO2 with W shows a systematic reduction in phase transition temperature up to 33°C for 4 wt% W-doped VO2. For 3 wt% W-doped VO2, the elastic modulus values enhance by 50%. The fracture toughness of 3 wt% W-doped VO2 shows an enhancement of fourfold compared to the undoped VO2. The dynamic compressive strength of 3 wt% W-doped VO2–UHMWPE polymer composite at room temperature is found to be 7% higher than the undoped VO2—composite.  相似文献   
53.
The present work is focused on optimization of Fe–Mo content, which is essential for transient liquid phase formation and densification, during in‐situ reaction sintering of nanostructured titanium boride (TiB) in the bulk form. The principle objective is to develop a systematic understanding of how the Fe–Mo additions affect the densification, microstructure, and hardness of the TiB nano‐ceramic. Various TiB ceramic compositions, with varying Fe–Mo content and retaining a high‐volume fraction of TiB in the final microstructure, were made by the electric‐field‐activated‐sintering (EFAS) technique. An increase in Fe–Mo content is found to decrease the beginning point of densification temperature/time during the consolidation process through transient liquid phase formation. It is shown that at the optimum level of Fe–Mo, which is around 1.5 wt%, the density and hardness reach maximum levels with a least amount of spatial segregation of Fe within the ceramic. Interestingly, it has been found that Mo is uniformly incorporated within the orthorhombic lattice of the boride, while Fe is largely segregated to β‐Ti phase. At the optimal Fe–Mo content (1.5 wt%), a relative density of 99.7% and a Vickers hardness of 2050 ± 40 kg/mm2 were achieved. From microstructural and X‐ray diffraction analyses, it is found that a high proportion of TiB (>99 vol%), with a least amount of metallic ductile phase, is formed in this composition.  相似文献   
54.
Multiple Sclerosis (MS) is an inflammatory demyelinating neurodegenerative disorder of the brain and spinal cord that causes significant disability in young adults. Although the precise aetiopathogenesis of MS remains unresolved, its pathological hallmarks include inflammation, demyelination, axonal injury (acute and chronic), astrogliosis and variable remyelination. Despite major recent advances in therapeutics for the early stage of the disease there are currently no disease modifying treatments for the progressive stage of disease, whose pathological substrate is axonal degeneration. This represents the great and unmet clinical need in MS. Against this background, human stem cells offer promise both to improve understanding of disease mechanism(s) through in-vitro modeling as well as potentially direct use to supplement and promote remyelination, an endogenous reparative process where entire myelin sheaths are restored to demyelinated axons. Conceptually, stem cells can act directly to myelinate axons or indirectly through different mechanisms to promote endogenous repair; importantly these two mechanisms of action are not mutually exclusive. We propose that discovery of novel methods to invoke or enhance remyelination in MS may be the most effective therapeutic strategy to limit axonal damage and instigate restoration of structure and function in this debilitating condition. Human stem cell derived neurons and glia, including patient specific cells derived through reprogramming, provide an unprecedented experimental system to model MS “in a dish” as well as enable high-throughput drug discovery. Finally, we speculate upon the potential role for stem cell based therapies in MS.  相似文献   
55.
So-called sdvanced oxidation involves the generation of free radical hydroxy species. Ozone, a highly unstable compound, liberates such radicals, which can be used for bleaching. In this work grey cotton fabric was bleached with an ozone/oxygen gas mixture, and the effects of ozone concentration and treatment time on the properties of the bleached fabric were studied. The properties evaluated were whiteness index, strength, elongation, extent of impurities (size and wax) removed, degree of chemical modification (carboxyl and aldehyde groups) and reactive dye take-up. These properties were compared to those from conventionally bleached materials (acid desize-scour-peroxide/calcium hypochlorite bleach). The results show that an acceptable degree of whiteness (ready for dyeing) can be obtained by ozone bleaching in a very short time. This process is environmentally acceptable because it is does not use harmful chemicals, it requires a very low quantity of water, and bleaching is achieved in a very short time at room temperature.  相似文献   
56.
57.
We report three neonates, one boy and two girls, born to an inbred Arab family who had cortical dysplasia, probably agyria-pachygyria, and agenesis of the corpus callosum. All had asphyxia, intractable seizures, and increased muscle tone at birth and died in the neonatal period. Congenital microcephaly or dysmorphic features were absent. Cytogenetic abnormality, metabolic disorder, and intrauterine infection were excluded. These cases suggest a new cerebral dysgenesis syndrome with autosomal recessive inheritance.  相似文献   
58.
Ray–based representations can model complex light transport but are limited in modeling diffraction effects that require the simulation of wavefront propagation. This paper provides a new paradigm that has the simplicity of light path tracing and yet provides an accurate characterization of both Fresnel and Fraunhofer diffraction. We introduce the concept of a light field transformer at the interface of transmissive occluders. This generates mathematically sound, virtual, and possibly negative‐valued light sources after the occluder. From a rendering perspective the only simple change is that radiance can be temporarily negative. We demonstrate the correctness of our approach both analytically, as well by comparing values with standard experiments in physics such as the Young's double slit. Our implementation is a shader program in OpenGL that can generate wave effects on arbitrary surfaces.  相似文献   
59.
Rectangles in a plane provide a very useful abstraction for a number of problems in diverse fields. In this paper we consider the problem of computing geometric properties of a set of rectangles in the plane. We give parallel algorithms for a number of problems usingn processors wheren is the number of upright rectangles. Specifically, we present algorithms for computing the area, perimeter, eccentricity, and moment of inertia of the region covered by the rectangles inO(logn) time. We also present algorithms for computing the maximum clique and connected components of the rectangles inO(logn) time. Finally, we give algorithms for finding the entire contour of the rectangles and the medial axis representation of a givenn × n binary image inO(n) time. Our results are faster than previous results and optimal (to within a constant factor).The work of Sung Kwan Kim was supported by NSF Grant CCR-87-03196 and the work of D. M. Mount was partially supported by National Science Foundation Grant CCR-89-08901.  相似文献   
60.
By the year 2050, the world’s population is predicted to have grown to around 9–10 billion people. The food demand in many countries continues to increase with population growth. Various abiotic stresses such as temperature, soil salinity and moisture all have an impact on plant growth and development at all levels of plant growth, including the overall plant, tissue cell, and even sub-cellular level. These abiotic stresses directly harm plants by causing protein denaturation and aggregation as well as increased fluidity of membrane lipids. In addition to direct effects, indirect damage also includes protein synthesis inhibition, protein breakdown, and membranous loss in chloroplasts and mitochondria. Abiotic stress during the reproductive stage results in flower drop, pollen sterility, pollen tube deformation, ovule abortion, and reduced yield. Plant nutrition is one of the most effective ways of reducing abiotic stress in agricultural crops. In this paper, we have discussed the effectiveness of different nutrients for alleviating abiotic stress. The roles of primary nutrients (nitrogen, phosphorous and potassium), secondary nutrients (calcium, magnesium and sulphur), micronutrients (zinc, boron, iron and copper), and beneficial nutrients (cobalt, selenium and silicon) in alleviating abiotic stress in crop plants are discussed.  相似文献   
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