MECHANICAL RESPONSE ANALYSIS AND TREATMENT MEASURES OF PARTITION WALL OF METRO STATION

In the process of metro station construction, the partition wall is usually used to prevent the displacement of the soil behind the wall to ensure the construction platform. This research aims to analyze the response of partition wall to keep the safety of the structure. The time-horizontal displacement and cracks of the partition wall are measured during the process of metro station construction. The finite element software FLAC 3D is used to simulate the response of partition wall, and the reasons of partition wall cracking and displacement are analyzed by finite element simulation and measurement data. The stiffness and self-stability of the partition wall in the station is powerful, the stress concentration appeared on the central area and caused cracks of the partition wall. Reducing the pressure exerted on the partition wall and shifting partial pressure exerted on the partition wall by the construction of the medium plate can solve the tress concentration problem. Through the data analysis of the strengthened partition wall, the reinforcement effect is good, ensuring the safety of the subsequent construction. The causes of partition wall cracking are found during process of metro station construction, and the solution proposed in this paper is effective. Engineers can refer to this paper to analyze the response of partition wall in the construction of similar structures, which can ensure construction safety and reduce construction cost

Zigzag graphene nanoribbons without inversion symmetry

Graphene on a substrate will suffer an inversion-symmetry-breaking (ISB) lattice potential. Taking electron-electron interaction into account, we study in this paper the possibility of half-metallicity and noncollinear (NC) magnetic phase for graphene zigzag nanoribbons without inversion symmetry. At half-filling it is found that half-metallic(HM) state can be achieved at an intermediate value of the ISB potential due to its competition with the electron-electron interaction. Away from half-filling, the phase diagrams of doping versus ISB potential for different ribbon width are given, where the regimes for the HM states and NC magnetic state are clearly indicated and discussed. For ribbons with perfect edges, we predict a topological transition between two HM states with different magnetic structures, which is accompanied by an abrupt transition of electrical conductance along the ribbon from $2e^2/h$ to $e^2/h$.Comment: 7 pages, 7 figure

Rigid vortices in MgB2

Magnetic relaxation of high-pressure synthesized MgB$_2$ bulks with different thickness is investigated. It is found that the superconducting dia-magnetic moment depends on time in a logarithmic way; the flux-creep activation energy decreases linearly with the current density (as expected by Kim-Anderson model); and the activation energy increases linearly with the thickness of sample when it is thinner than about 1 mm. These features suggest that the vortices in the MgB$_2$ are rather rigid, and the pinning and creep can be well described by Kim-Anderson model.Comment: Typo corrected & reference adde

Current-voltage characteristics of NdFeAsO0.85F0.15 and NdFeAsO0.85 superconductors

The vortex phase diagrams of NdFeAsO0.85F0.15 and NdFeAsO0.85 superconductors are determined from the analysis of resistivity and current-voltage (I-V) measurements in magnetic fields up to 9 T. A clear vortex glass to liquid transition is identified only in the oxygen deficient NdFeAsO0.85, in which I-V curves can be well scaled onto liquid and glass branches consistent with the vortex glass theory. With increasing magnetic field, the activation energy U0, deduced from the Arrhenius plots of resistivity based on the thermally activated flux-flow model (TAFF), decays more quickly for NdFeAsO0.85F0.15 than for NdFeAsO0.85. Moreover, the irreversibility field Hirr of NdFeAsO0.85 increases more rapidly than that of NdFeAsO0.85F0.15 with decreasing temperature. These observations evidence the strong vortex pinning effects, presumably caused by the enhanced defects and disorders in the oxygen deficient NdFeAsO0.85. It is inferred that the enhanced defects and disorder can be also responsible for the vortex glass to liquid transition in the NdFeAsO0.85.Comment: 19 pages, 5 figure

Psychological Stress Induces Temporary Masticatory Muscle Mechanical Sensitivity in Rats

To explore the relationship between psychological stress and masticatory muscle pain, we created a communication stress animal model to determine whether psychological stress could induce increased mechanical sensitivity in masticatory muscles and to study the changes of mechanical nociceptive thresholds after stress removal. Forty-eight male Sprague-Dawley rats were divided into a control group (CON), a foot-shocked group (FS, including 3 subgroups recorded as FS-1, FS-2, and FS-3), a psychological stress group (PS), and a drug treatment group (DT). PS and DT rats were confined in a communication box for one hour a day to observe the psychological responses of neighboring FS rats.Measurements of the mechanical nociceptive thresholds of the bilateral temporal and masseter muscles showed a stimulus-response relationship between psychological stress and muscle mechanical sensitivity. The DT rats, who received a diazepam injection, showed almost the same mechanical sensitivity of the masticatory muscles to that of the control in response to psychological stress. Fourteen days after the psychological stressor was removed, the mechanical nociceptive thresholds returned to normal. These findings suggest that psychological stress is directly related to masticatory muscle pain. Removal of the stressor could be a useful method for relieving mechanical sensitivity increase induced by psychological stress

Acute Symptoms after a Community Hydrogen Fluoride Spill

OBJECTIVES: This study was conducted to describe the demographic characteristics, and clinical signs and symptoms of patients who visited a general hospital because of the release of chemically hazardous hydrogen fluoride that occurred on September 27, 2012 in Gumi City, Korea. METHODS: The medical records at 1 general hospital 9 km from the accident site were reviewed using a standardized survey format. There were 1,890 non-hospitalized and 12 hospitalized patients exposed to hydrogen fluoride between September 27 and October 13 2012. RESULTS: Among the 12 hospitalized patients, 11 were discharged within 1 week and the other was hospitalized for 10 days. The chief complaints were respiratory symptoms such as hemoptysis and shortness of breath, gastrointestinal symptoms, neurologic symptoms, sore throat, and lip burn. The number of non-hospitalized patients exhibited a bimodal distribution, peaking on the first and twelfth days after the accident. Their chief complaints were sore throat (24.1%), headache (19.1%), cough (13.1%), and eye irritation (9.2%); some patients were asymptomatic (6.2%). Patients who visited the hospital within 3 days (early patients) of the spill more often had shortness of breath (27.0%) and nausea (6.3%) as the chief complaints than patients who visited after 3 days (late patients) (3.5% and 2.6%, respectively). However, cough and rhinorrhea were more common in the late patients (14.0% and 3.3%, respectively) than in the early patients (5.0% and 0.0%, respectively). Patients who were closer to the accident site more often had shortness of breath and sputum as the chief complaints than patients who were farther away. The mean serum calcium concentration was 9.37 mg/dL (range: 8.4–11.0 mg/dL); none of the patients had a decreased serum calcium level. Among 48 pulmonary function test results, 4 showed decreased lung function. None of the patients had abnormal urine fluoride levels on the eighth day after exposure. CONCLUSIONS: Patients hospitalized due to chemical hazard release of hydrogen fluoride had acute respiratory, gastrointestinal, and neurologic health problems. Non-hospitalized patients have acute symptoms mainly related to upper respiratory irritation

Sulforaphane induces adipocyte browning and promotes glucose and lipid utilization

Scope: Obesity is closely related to the imbalance of white adipose tissue storing excess calories, and brown adipose tissue dissipating energy to produce heat in mammals. Recent studies revealed that acquisition of brown characteristics by white adipocytes, termed “browning,” may positively contribute to cellular bioenergetics and metabolism homeostasis. The goal was to investigate the putative effects of natural antioxidant sulforaphane (1-isothiocyanate-4-methyl-sulfonyl butane; SFN) on browning of white adipocytes. Methods and Results: 3T3-L1 mature white adipocytes were treated with SFN for 48 h, and then the mitochondrial content, function, and energy utilization were assessed. SFN was found to induce 3T3-L1 adipocytes browning based on the increased mitochondrial content and activity of respiratory chain enzymes, whereas the mechanism involved the upregulation of nuclear factor E2-related factor 2/ sirtuin1/ peroxisome proliferator-activated receptor gamma coactivator 1 alpha signaling. SFN enhanced uncoupling protein 1 expression, a marker for brown adipocyte, leading to the decrease in cellular ATP. SFN also enhanced glucose uptake and oxidative utilization, lipolysis and fatty acid oxidation in 3T3-L1 adipocytes. Conclusion: SFN-induced browning of white adipocytes enhanced the utilization of cellular fuel, and the application of SFN is a promising strategy to combat obesity and obesity-related metabolic disorder

Treatment of instability with scapular notching and glenoid component loosing by partial mixed different implant revision

In general, reverse shoulder arthroplasty revision is performed using the same implant for both the humerus and glenoid components. However, the authors of the present case used different implants from what was used previously for treating instability with scapular notching and glenoid aseptic loosening and report the case