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1.
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   
2.
In recent years, frequent damage to wind turbines by winter lightning has been reported in the region along the Sea of Japan. It is a serious finding that lightning hits concentrate on wind turbines in this region. The authors investigated the increase rate of the frequency of lightning hits on wind turbines due to wind turbine construction by using LLS (lightning location system) data. As a result, an experimental formula to estimate the increase rate of the frequency of lightning hits on wind turbines as a function of parameters related to the construction conditions, namely the height of wind turbines, the height above sea level, and the latitude, is proposed.  相似文献   
3.
In this paper, the mechanical behavior of inclined jointed rock masses during tunneling is considered. Such rock masses can be considered as an assembly of discrete blocks with the discontinuities having a significant influence on the mechanical behavior. To simulate this situation, a discrete numerical analysis method, Discontinuous Deformation Analysis (DDA), is applied. The DDA results show the existence of stress arching in the rock masses during tunneling. This stress arching is the primary influence on the stress distribution and surface subsidence. In addition, the stress arching is affected by the dip angle of the jointed rock masses. Moreover, the DDA results are in good agreement with experiments, explaining the reason for the asymmetrical vertical stress and surface subsidence obtained in laboratory tests. These results suggest that DDA can be applied to model the tunneling behavior of complicated discontinuous rock masses.  相似文献   
4.
ABSTRACT

This paper proposes a novel, simultaneous bipedal locomotion method using haptics for remote operation of biped robots. In general, traditional biped walking methods require very high computational power and advanced controllers to perform the required task. However, in this proposed method, a master exoskeleton attached to the human’s lower body is used to obtain the trajectory and haptic information to generate the trajectory of the slave biped robot in real time. Lateral motion of the center of mass of the biped is constrained in this experiment. Also, it is considered that no communication delay is presented in between the two systems in this experiment, and they are not discussed in this paper. Since a direct motion transmission is used in the proposed method, this method is quite straight forward and a simultaneous walking can be realized at the same time with high performance. Also, it does not require an exact dynamic model of the biped or specific method to plan the trajectory. The gait pattern of the biped is directly determined by that of the human. Also, the operator can feel the remote environment through the exoskeleton robot. Results obtained from the experiments validate the proposed method.  相似文献   
5.
Reactive oxygen and nitrogen species have been implicated in diverse pathophysiological conditions, including inflammation, neurodegenerative diseases and cancer. Accumulating evidence indicates that oxidative damage to biomolecules including lipids, proteins and DNA, contributes to these diseases. Previous studies suggest roles of lipid peroxidation and oxysterols in the development of neurodegenerative diseases and inflammation-related cancer. Our recent studies identifying and characterizing carbonylated proteins reveal oxidative damage to heat shock proteins in neurodegenerative disease models and inflammation-related cancer, suggesting dysfunction in their antioxidative properties. In neurodegenerative diseases, DNA damage may not only play a role in the induction of apoptosis, but also may inhibit cellular division via telomere shortening. Immunohistochemical analyses showed co-localization of oxidative/nitrative DNA lesions and stemness markers in the cells of inflammation-related cancers. Here, we review oxidative stress and its significant roles in neurodegenerative diseases and cancer.  相似文献   
6.
This paper proposes some basic methods of content search yielding high user utility or user's satisfaction from numerous information sources scattered over large‐scale networks. In these methods, the search policy is decided by the estimated user utility gain and/or current user utility for each search action, and the most favorable combination of information sources and search content items is selected so as to enlarge the total user utility of the entire search activity. In addition, we evaluate the efficiency of the methods by computer simulations, in which we specify the network topology, user utility functions, probabilities of existence of the search content items in each information source, and so on, apply the proposed methods and other methods for comparison, and compare their aggregate utility gains as an estimation index. The proposed methods are found to achieve good performance in general and an index value about 2.45 times that of ordinary search is observed in an extreme simulation scenario. We discuss the pros and cons of the proposed methods for all the simulation scenarios.  相似文献   
7.
8.
Partially fluorinated metal oxides were studied for manufacturing dichloropentafluoropropanes (CF3CF2CHCl2 and CCl2FCF2CHClF) and controlling the selectivity of their isomers. When activated by elemental fluorine or dichlorodifluoromethane, metal oxides such as TiO2, HfO2, Al2O3, and ZrO2, exhibited catalytic activity in the reaction of dichlorofluoromethane with tetrafluoroethylene. In the case of the TiO2 catalyst, the more fluorine incorporated, the higher the selectivity was for the CCl2FCF2CHClF formation. The fluorine-activated TiO2 catalyst was identified by XRD and XPS as a mixture of TiO2 and partially fluorinated TiO2 including TiOF2.  相似文献   
9.
The effects of fatty acid, monoacylglycerol, and polyglycerol fatty acid ester with varying chain length in their acyl chains on the extent of complex formation (complex index) and in vitro enzymatic digestibility of gelatinized potato starch were investigated. The complex index increased with increase in the concentration of the ligands (fatty acid, monoacylglycerol, and polyglycerol fatty acid ester), with the plateau in the complex index value depending on the type of ligands. In comparison of complex index among fatty acid-samples, the complex index maximum increased as the chain length increased up to octanoic acid and then decreased. In comparison of complex index among fatty acid-, monoacylglycerol-, and polyglycerol fatty acid ester-samples at each acyl chain, the complex index maximum followed the order polyglycerol fatty acid ester > monoacylglycerol > fatty acid. Fatty acid, monoacylglycerol, and polyglycerol fatty acid ester with long acyl chains greatly reduced the enzymatic hydrolysis of starch. Polyglycerol fatty acid ester with palmitic acid chains was the strongest inhibitor of starch hydrolysis, suggesting that further complex formation may occur during the hydrolysis of gelatinized starch (enzyme-annealing).  相似文献   
10.
A new integral experiment with a deuteron–triton fusion (DT) neutron beam started in order to validate scattering cross section data. First the DT neutron beam was constructed with a collimator. The performance of the collimator system and the characteristics of the DT neutron beam were measured. Second a new integral experiment for type 316 stainless steel (SS316) was carried out with this DT neutron beam. The DT neutron beam of 3.5 cm in diameter was injected to the front surface center of an SS316 cylindrical assembly. Reaction rates of the 93Nb(n,2n)92mNb reaction in the assembly were measured with the activation foil method and were calculated with the Monte Carlo transport calculation code. The measurement points were located at three positions, on the center of the beam axis and at 15 cm and 30 cm apart from the axis. The ratio of calculation to experiment of the 93Nb(n,2n)92mNb reaction rate became smaller than 1 with the distance from the beam axis. Then, the dependency of each reaction rate on scattering angle was calculated. It was proved that at off-axis positions, where C/E is smaller than 1, 90° scattering contribute relatively larger than at on-axis positions and backward scattering made little contribution to the results in this experiment. The reasons of the discrepancy between the measured and calculated data will be investigated.  相似文献   
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