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1.
Journal of Infrared, Millimeter, and Terahertz Waves - Various regimes of hybrid, bulk-surface, modes being excited in the clinotron oscillator with a sheet electron beam and nonuniform grating...  相似文献   
2.
Pyogenic spondylodiscitis can cause severe osteolytic and destructive lesions in the spine. Elderly or immunocompromised individuals are particularly susceptible to infectious diseases; specifically, infections in the spine can impair the ability of the spine to support the trunk, causing patients to be bedridden, which can also severely affect the physical condition of patients. Although treatments for osteoporosis have been well studied, treatments for bone loss secondary to infection remain to be elucidated because they have pathological manifestations that are similar to but distinct from those of osteoporosis. Recently, we encountered a patient with severely osteolytic pyogenic spondylodiscitis who was treated with romosozumab and exhibited enhanced bone formation. Romosozumab stimulated canonical Wnt/β-catenin signaling, causing robust bone formation and the inhibition of bone resorption, which exceeded the bone loss secondary to infection. Bone loss due to infections involves the suppression of osteoblastogenesis by osteoblast apoptosis, which is induced by the nuclear factor-κB and mitogen-activated protein kinase pathways, and osteoclastogenesis with the receptor activator of the nuclear factor-κB ligand-receptor combination and subsequent activation of the nuclear factor of activated T cells cytoplasmic 1 and c-Fos. In this study, we review and discuss the molecular mechanisms of bone loss secondary to infection and analyze the efficacy of the medications for osteoporosis, focusing on romosozumab, teriparatide, denosumab, and bisphosphonates, in treating this pathological condition.  相似文献   
3.
This study presents systematic packaging design tools integrating functional and environmental consequences on product life cycle. To design packaging for sustainability, the trade-offs between functional and environmental aspects of packaging throughout the product life cycle should be considered. However, it is difficult for packaging designers to understand the overall trade-offs because the extent of the design consequences on the entire life cycle of packaging and its contents is unclear. We developed two tools for packaging design: the Life Cycle Association Matrix (LCAM) and the Function Network Diagram (FND). The following three steps, based on literature reviews and interviews with industrial experts, were applied. Firstly, we listed the product functions and design variables related to the functions as the attributes allocated to the product life cycle. Secondly, the attributes were connected appropriately based on causal relationships. Lastly, we identified the factors to support decision making in the packaging design procedure. As a result, the LCAM depicts the design consequences on the life cycle, and the FND determines the stakeholders affected by the design consequences. Two case studies were demonstrated to analyze the trade-offs by using our tools. In the case studies, a liquid laundry detergent bottle and a milk carton were redesigned. The tools identified the design consequences and stakeholders affected by the redesign of the usability and protective function for the detergent and milk cases, respectively. The results showed the significance of understanding the design consequences on the product life cycle by integrating the functional and environmental aspects.  相似文献   
4.
5.
The deuterium (hydrogen) passivation effect on acceptors in boron-doped CVD homoepitaxial diamond was studied by electrical (Hall-effect) and secondary ion mass spectroscopy (SIMS) measurements. Deuterium was incorporated into the samples using microwave (MW) deuterium plasma at 673 K for 2–24 h. We observed the progress of acceptor passivation with p-type conduction, which finally resulted in a highly resistive state.  相似文献   
6.
We investigated rutile-type titanium dioxide (TiO2) films for possible use as a high-k gate insulator. The TiO2 thin films were directly deposited on Si substrates using a RF magnetron sputtering method with a sintered oxide target. A single phase of rutile-type TiO2 whose dielectric constant of approximately 75 was obtained when the film was deposited in an inert gas atmosphere and annealed at 800 °C in an oxidizing gas atmosphere. The oxygen ions were deficient in the as-deposited film, and consequently, a sufficient oxygen supply was needed to crystallize the film to a single phase of rutile during the post-annealing. However, the interfacial SiO2 layer between the TiO2 and the Si substrate simultaneously grew thicker than 2 nm. As the interfacial SiO2 grew, the leakage current was decreased and the equivalent oxide thickness was increased, in the Au/rutile-type TiO2/Si capacitor. Therefore, we concluded that the growth of the interfacial SiO2 layer thicker than 2 nm is inevitable to form the single phase of rutile-type TiO2 and to decrease the leakage.  相似文献   
7.
Hot-carrier degradation of lightly doped drain (LDD) MOSFET's under ac stress is investigated. Enhanced ac degradation occurs in LDD MOSFET's as well as in single-drain MOSFET's. However, there is a peculiar degradation mechanism in LDD MOSFET's. For single-drain MOSFET's, enhanced ac degradation appears in both threshold voltage and transconductance at stress drain voltages larger than a critical value. On the other hand, for LDD MOSFET's, although the enhanced degradation in threshold voltage and transconductance appears at stress drain voltages larger than a critical value, the enhanced degradation in transconductance appears even under stress drain voltages lower than the critical value. The difference in the ac-enhanced degradation between LDD and single-drain structures can be explained by a hot hole generated neutral-electron-trap model and the change in hot-hole-injected oxide region according to stress bias conditions  相似文献   
8.
A molecular orbital approach to materials design has recently made great progress. This approach is based on the electronic structure calculations by the DV-Xα cluster method. In this paper recent progress in this approachis reviewed. In particular  相似文献   
9.
ABSTRACT: The thermal evolution behavior of the organic free radicals induced in irradiated black pepper was studied by electron spin resonance spectroscopy. To analyze the time-dependent evolution process, we used the theory of transient phenomena, that is, an ordinal differential equation, as well as the nonlinear least squares numerical method. We found that the radical evolution that occurred in the irradiated pepper obeys a single exponential function and yields a unique time constant. The evolution of the organic free radical undergoes a simple reaction process of a single radical species.  相似文献   
10.
The electrochemical behavior of ferrocene (Fc) and ferricenium (Fc+) was investigated by cyclic voltammetry with convolutional and semi-differential electroanalyses in the temperature range 298-373 K in the hydrophobic room temperature ionic liquid systems consisting of bis(trifluoromethanesulfone)imide anion with quaternary ammonium cation. The experimental results indicated that the redox reaction of Fc/Fc+ was reversible in this ionic liquid and the charge-transfer rate constant (k0) has been obtained. Mass transport towards the electrode is a simple diffusion process and the diffusion coefficient (D) for Fc/Fc+ has been also calculated. These results indicated that the k0 and D increased with increasing temperature in ionic liquids. The validity of the Arrhenius law was verified by investigating the temperature dependences of k0 and D.  相似文献   
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