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61.
62.
Most approaches to multi-project scheduling are based on the assumption that resources can be transferred between projects
without any expense in time and cost. As this assumption often is not realistic, we generalise the multi-project scheduling
problem (RCMPSP) by additionally including transfer times and cost. To integrate this aspect, in a first step, we develop
a framework for considering resource transfers in single- and multi-project environments. It includes managerial approaches
to handle resource transfers, a classification of resource transfer types and new roles that resources can take in these transfers.
Afterwards, we define the multi-project scheduling problem with transfer times (RCMPPTT) and formulate it in a basic and an
extended version as integer linear programmes. Eventually, it is supplemented for the first time by cost considerations and
introduced as resource constrained multi-project scheduling problem with transfer times and cost (RCMPSPTTC). Computational
experiments compare the presented managerial approaches and prove the necessity of explicitly considering transfer times in
project scheduling already during the planning phase. Moreover, the experiments evaluate the presented MIP models and show
that specialised solution procedures are vital. 相似文献
63.
Enn Seppet Marju Gruno Ants Peetsalu Zemfira Gizatullina Huu Phuc Nguyen Stefan Vielhaber Manfred H.P. Wussling Sonata Trumbeckaite Odeta Arandarcikaite Doreen Jerzembeck Maria Sonnabend Katharina Jegorov Stephan Zierz Frank Striggow Frank N. Gellerich 《International journal of molecular sciences》2009,10(5):2252-2303
Mitochondrial dysfunction is a hallmark of almost all diseases. Acquired or inherited mutations of the mitochondrial genome DNA may give rise to mitochondrial diseases. Another class of disorders, in which mitochondrial impairments are initiated by extramitochondrial factors, includes neurodegenerative diseases and syndromes resulting from typical pathological processes, such as hypoxia/ischemia, inflammation, intoxications, and carcinogenesis. Both classes of diseases lead to cellular energetic depression (CED), which is characterized by decreased cytosolic phosphorylation potential that suppresses the cell’s ability to do work and control the intracellular Ca2+ homeostasis and its redox state. If progressing, CED leads to cell death, whose type is linked to the functional status of the mitochondria. In the case of limited deterioration, when some amounts of ATP can still be generated due to oxidative phosphorylation (OXPHOS), mitochondria launch the apoptotic cell death program by release of cytochrome c. Following pronounced CED, cytoplasmic ATP levels fall below the thresholds required for processing the ATP-dependent apoptotic cascade and the cell dies from necrosis. Both types of death can be grouped together as a mitochondrial cell death (MCD). However, there exist multiple adaptive reactions aimed at protecting cells against CED. In this context, a metabolic shift characterized by suppression of OXPHOS combined with activation of aerobic glycolysis as the main pathway for ATP synthesis (Warburg effect) is of central importance. Whereas this type of adaptation is sufficiently effective to avoid CED and to control the cellular redox state, thereby ensuring the cell survival, it also favors the avoidance of apoptotic cell death. This scenario may underlie uncontrolled cellular proliferation and growth, eventually resulting in carcinogenesis. 相似文献
64.
Qiquan Feng Caspar J. McConville Doreen D. Edwards 《Journal of the American Ceramic Society》2005,88(6):1455-1460
The microstructures and dielectric properties of multilayer ceramic capacitors based on reoxidized Ba(Ti0.88 ,Zr0.12 )O3 (BTZ) materials with Ni electrodes were studied using transmission electron microscopy. Dielectric measurements showed that the BTZ materials exhibited frequency relaxation effects. Although X-ray diffraction showed a single pseudocubic phase, split and elongated electron diffraction spots were observed using selected area diffraction (SAD). There were no super-lattice diffraction spots in the SAD pattern. The microstructures of BTZ dielectric materials were observed at dynamical diffraction conditions, and multidomain structures coexisting in one grain were imaged with high contrast. Bright field and centered dark field images revealed the pseudocubic (100) and (110) domain walls had developed in some regions of the same grain with normal ferroelectric macro-domain features, and bend contours and distorted domain walls were seen. Defects with the features of low angle grain boundaries, dislocations, and phase boundaries were also observed. Uneven distribution of internal stress and coexistence of multiphases and multidomains in individual grains were considered to be responsible for the frequency relaxor behavior observed in these materials. A model of the evolution of the microstructures with the decrease of temperature is presented. 相似文献
65.
Doreen Kunze Kati Erdmann Michael Froehner Manfred P. Wirth Susanne Fuessel 《International journal of molecular sciences》2013,14(6):12297-12312
The overexpression of antiapoptotic genes, such as Bcl-xL and survivin, contributes to the increased survival of tumor cells and to the development of treatment resistances. In the bladder cancer cell lines EJ28 and J82, the siRNA-mediated knockdown of survivin reduces cell proliferation and the inhibition of Bcl-xL sensitizes these cells towards subsequent chemotherapy with mitomycin C and cisplatin. Therefore, the aim of this study was to analyze if the simultaneous knockdown of Bcl-xL and survivin might represent a more powerful treatment option for bladder cancer than the single inhibition of one of these target genes. At 96 h after transfection, reduction in cell viability was stronger after simultaneous inhibition of Bcl-xL and survivin (decrease of 40%–48%) in comparison to the single target treatments (decrease of 29% at best). Furthermore, simultaneous knockdown of Bcl-xL and survivin considerably increased the efficacy of subsequent chemotherapy. For example, cellular viability of EJ28 cells decreased to 6% in consequence of Bcl-xL and survivin inhibition plus cisplatin treatment whereas single target siRNA plus chemotherapy treatments mediated reductions down to 15%–36% only. In conclusion, the combination of simultaneous siRNA-mediated knockdown of antiapoptotic Bcl-xL and survivin—a multitarget molecular-based therapy—and conventional chemotherapy shows great potential for improving bladder cancer treatment. 相似文献
66.
利用2,2-双[4-(4-氨基苯氧基)苯1丙烷及偏苯三酸酐合成聚酰亚胺齐聚物,并用此齐聚物改性环氧树脂胶粘剂。使用红外光谱、凝胶化时间、接触角和拉伸剪切强度对改性胶粘剂性能进行表征。结果表明,齐聚物的加入对环氧树脂固化反应具有促进作用;当100质量份环氧中加入16份齐聚物时,胶粘剂力学性能最佳;当齐聚物用量为20份时;胶粘剂表面能最高。 相似文献
67.
Yosephine Andriani Jing Song Poh Chong Lim Debbie Hwee Leng Seng Doreen Mei Ying Lai Siew Lang Teo Junhua Kong Xiaobai Wang Xiaowu Zhang Songlin Liu 《Ceramics International》2019,45(4):4909-4917
As the structural analogue of graphene, boron nitride nanosheets (BNNSs) are anticipated to have a wide range of potential applications. BNNSs exhibit good mechanical properties, outstanding thermal conductivity, oxidation and chemical stability and are excellent electrical insulators. While BNNSs have gained recognition as one of the most versatile 2D materials in recent years, their application in research and industry is still hampered by the lack of methods to produce BNNSs in large quantity and a cost-effective way. In this study, we report highly efficient h-BN exfoliation via the oxygen doping-facilitated liquid exfoliation. Oxygen atoms are introduced into the hexagonal boron nitride (h-BN) structure via a facile thermal treatment. The relationship of thermal treatment, structural changes and h-BN exfoliation are studied to elucidate the key factor for advancing the BNNS production. The optimum concentration of hydroxyl groups and weakening of interlayer interactions have synergistically facilitated the delamination of h-BN in water under mild exfoliation conditions, resulting in up to 1255% yield increment and without noticeable new defects in the BNNS structure as compared with the untreated control. An efficient and environmentally friendly exfoliation process of h-BN is a crucial starting point towards the cost-effective and mass production of BNNSs which is needed for the currently identified and myriad future applications of BNNSs. 相似文献
68.
Kathiresan Purushothaman Jerryl Kim Han Tan Doreen Lau Jolly M. Saju Natascha M. Thevasagayam Caroline Lei Wee Shubha Vij 《International journal of molecular sciences》2021,22(4)
A reduction in daily caloric or nutrient intake has been observed to promote health benefits in mammals and other vertebrates. Feed Restriction (FR), whereby the overall food intake of the organism is reduced, has been explored as a method to improve metabolic and immune health, as well as to optimize productivity in farming. However, less is known regarding the molecular and physiological consequences of FR. Using the model organism, Danio rerio, we investigated the impact of a short-term (month-long) FR on growth, gut morphology and gene expression. Our data suggest that FR has minimal effects on the average growth rates, but it may affect weight and size heterogeneity in a sex-dependent manner. In the gut, we observed a significant reduction in gut circumference and generally lower mucosal heights, whereas other parameters remained unchanged. Gene Ontology (GO), EuKaryotic Orthologous Groups (KOG), and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis identified numerous metabolic, reproductive, and immune response pathways that were affected by FR. These results broaden our understanding of FR and contribute towards growing knowledge of its effects on vertebrate health. 相似文献
69.
This paper presents a detailed meta-analysis of end and primary energy use for heating, cooling and ventilation of 11 low-energy non-residential buildings and one residential building in Germany that belong to the EnOB research program launched by the German Federal Ministry for Economy. In particular, the analysis emphasizes the substantial impact of auxiliary energy use on the efficiency of heating and cooling performance. The investigated buildings employ environmental energy sources and sinks - such as the ground, ground water, rainwater and the ambient air - in combination with thermo-active building systems. These concepts are promising approaches for slashing the primary energy use of buildings without violating occupant thermal comfort. A limited primary energy use of about 100 kWhprim/(m2neta) as a target for the complete building service technology (HVAC and lighting) was postulated for all buildings presented. With respect to this premise, a comprehensive long-term monitoring in high time resolution was carried out over the course of two to five years, with an accompanying commissioning of the building performance. Measurements include the energy use for heating, cooling, and ventilation, as well as the auxiliary equipment, the performance of the environmental heat source and sink, and local climatic site conditions. 相似文献
70.
This paper introduces and evaluates a novel heating and cooling concept employing thermo-active building systems and environmental energy, harnessed from two 11-m3 rainwater cisterns for a 285-m2 residential building in passive house standard in Germany. The building strives for a significantly reduced primary energy use with carefully coordinated measures, such as high quality building envelope, by means of vacuum insulated panels, supply and exhaust air system with heat recovery, reduced solar heat gains (solar shading), and the integration of thermal solar collectors and photovoltaic in the plant system. On this premise, a comprehensive long-term monitoring in high time-resolution was carried out for the building for two years with an accompanying commissioning of the building performance. Measurements comprise the energy use for heating, cooling, and ventilation, as well as the auxiliary equipment, the performance of the environmental heat source and sink (rainwater cistern), thermal comfort, and local climatic site conditions. 相似文献