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• The activation of osteoclast in OVX rats could activate sensory nerves to release CGRP. • CGRP promoted serotonin release in the brainstem and spinal cord. • Increased brain-derived serotonin inhibited CGRP release in the femur. • CGRP and serotonin were related to osteoporosis and osteoporotic pain. Postmenopausal osteoporosis (PMO) and osteoporotic fracture seriously impair human health in developed countries. The present study aims to explore whether sensory nerves, calcitonin gene-related peptide (CGRP), and brain-derived serotonin are related to bone loss in ovariectomized (OVX) rats. Female rats were grouped into the ovariectomized (OVX) and sham surgery (SHAM) groups. Immunocytochemistry, western blotting, and qPCR were performed to detect CGRP expression in the femurs. The expression levels of serotonin and CGRP in the spinal cord and brainstem were estimated using western blotting, immunofluorescence, and qPCR. ELISA was used to evaluate the serum biomarkers of bone formation and resorption. Bone mineral density was measured using dual-energy X-ray (DXA) analysis. Femur microstructure was imaged by Micro CT. P values less than 0.05 were considered statistically significant. ELISA showed that serum bone alkaline phosphatase (BALP), tartrate-resistant acid phosphatase (TRAP), β-crosslaps, and β-ctx were increased in the OVX group. In the OVX group, in vivo bone mineral density, trabecular bone mineral density, bone volume fraction (BV/TV), and trabecular number (Tb. N) were significantly decreased, while trabecular spacing (Tb. Sp) and trabecular bone pattern factor (Tb. Pf) were markedly increased. In the OVX group, the expression levels of CGRP of the femur were significantly downregulated. In contrast, CGRP and serotonin expression was increased in the spinal cord of the OVX group. Serotonin expression was increased in the brainstem, brainstem nucleus raphe magnus (RMG), and nucleus raphe dorsalis (DRN). Our results indicated that the activation of osteoclast triggered the release of CGRP from nociceptive sensory nerve fibers and transmitted this painful stimulus to the dorsal horn of the spinal cord to release increased CGRP. The descending serotonergic inhibitory system was activated by increased CGRP levels of the spinal cord and promoted serotonin release in the brainstem RMG, DRN, and the spinal cord, contributing to the decreased CGRP level in bone tissue, which revealed a novel mechanism of bone loss in PMO. [ABSTRACT FROM AUTHOR]

• The ground states and the dynamics of the biased bosonic ladder are discussed. • The Meissner, Vortex and two new Plane Wave phases are predicted analytically. • Interestingly, the Plane Wave phases break both Z 2 and time-reversal symmetry. • Rich chiral Bolch oscillations are predicted to distinguish the novel phases. • The work gives an interesting way to explore phases in condensed physics dynamically. The ground states and the dynamics of a biased two-leg flux ladder in the presence of a gravitational field are discussed. In the absence of the gravitational field, the ground states and the critical condition of phase transition are obtained analytically. We identify the Meissner phase, Vortex phase, and interestingly, two new Plane Wave phases, that break both Z 2 and time-reversal symmetry, characterized by the imbalance particle density distribution, asymmetry double well energy band structure in Plane Wave I (PWI) phase and asymmetry single well energy band structure in Plane Wave II (PWII) phase, respectively. In the presence of a longitudinal dc gravitational field, rich chiral Bloch oscillation and Landau-Zener tunneling are predicted theoretically and confirmed numerically. The characteristics of the chiral Bloch oscillation can distinguish the novel phases intuitively. Our work gives an interesting way to discuss the quantum phase transitions in a dynamical way. [ABSTRACT FROM AUTHOR]

To efficiently utilize energy, refrigeration industries, including air conditioning, have put forward higher and higher requirements for the performances of copper pipes used for heat exchangers. Horizontal continuous casting of pipe blank is a key process in production of copper pipes, and optimization of its technological parameters has positive effects on improving the structure uniformity of casting blank. The stability of the performances of pipe blank also directly influences the quality of subsequent machining process. In this paper, numerical analysis was carried out for the temperature field and structure field during solidification of pipe blank in the crystallizer for horizontal continuous casting, and the steady-state sump depth and morphology in the crystallizer for continuous casting, which could be used to evaluate production safety, were obtained. Quantitative analysis was conducted for the laws of influence of different casting technological parameters, such as cooling water flow rate, withdrawal speed, and casting temperature, on the sump morphology in the crystallizer for casting blank and the final distribution of structure field in casting blank. Metallographic experiment was carried out for casting blank, and the results were compared visually with the structure field from simulation calculation, to provide measurable reference bases for further optimizing the horizontal casting technological parameters for copper pipes. [ABSTRACT FROM AUTHOR]

The realization and detection of two-leg ladders with the interplay of the artificial gauge field provide an ideal platform for investigations of the quantum phase transition and quantum dynamics. Here, we realize the spatio-temporal evolution dynamics of two-leg ladder systems with magnetic flux analytically and numerically. The quench dynamics induced by giving sudden quenches of initial density distributions of left and right leg components, rung-to-leg coupling ratios and magnetic flux from the ground state are discussed in detail. Affected by the chirality of ladder systems together with the tunneling between the two legs, rich and interesting quench dynamics observed, which including the Josephson Oscillations (JOs), Chiral Density Wave (CDW), Scissors Mode (SM), Periodic Torsional Vortex (PTV) and Periodic Torsional-Scissors Vortex (PTSV). Remarkably, we find that the oscillation frequency of the quench dynamics associated with coupling ratios and magnetic flux can be used to identify the phase transition between the Meissner phase and Vortex phase. Therefore, our work may provide an effective way to distinguish phase transitions by using quench dynamics. [ABSTRACT FROM AUTHOR]

Copper tubes are efficient heat exchange parts in refrigeration industry, and their quality has a bearing on the grade of corresponding products. The cooling process of copper tube after three-roll planetary rolling is a key step in the production of copper tube by the casting and rolling method, and its cooling effect matters to the quality of copper tube products. Aiming at the characteristics of motion of a rolled piece in the through water cooling with a cooling water jacket, the method of "stepwise" moving cooling water jacket was used in this paper to achieve equivalence to the motion of the rolled piece, realizing finite element simulation of the whole process of three-roll planetary rolling and cooling of copper tube. The velocity field and pressure field of the fluid in the cooling water model were analyzed, and it was found that there existed a flow "dead zone" with the velocity below 8 m/s, there was a "negative pressure" phenomenon, and there were more eddy currents occurring. Through the study on the temperature field during the cooling process of the rolled piece, it was found that there was a phenomenon of non-uniform temperature distribution in the cooling process of the rolled piece. With the maximum temperature difference at each monitoring point in the cooling process of rolled piece as the evaluation criterion for the uniformity of temperature distribution in the cooling process of rolled piece, the process parameters affecting the rolled piece cooling effect, including the size of water inlet, the size of water outlet, and the pressure of entering water, were studied respectively, and the optimum process parameter values for improving the quality of rolled pieces were finally obtained. The accuracy of the model was verified by comparatively analyzing the metallographic microstructure and microhardness between the factory produced sample and the thermally simulated sample. • Realize the whole process of three-roll planetary rolling and cooling of the tube. • Simulation method of "stepwise" moving cooling water jacket was used. • It was found that there existed a flow "dead zone". • There were "negative pressure" phenomenon and eddy current phenomena occurring. [ABSTRACT FROM AUTHOR]

Abstract: Removal of NO was studied in a lab-scale bubbling reactor. Effects of operation parameters such as pH value, H2O2 concentration, NO inlet concentration and reaction temperature on NO removal efficiency were investigated. The operation parameters included 250–1000ppm NO, 0.5–1.5mol/L H2O2, FeSO4 0.05mol/L, 2–6 pH, 25–70°C. As can be seen from the experimental results, pH value had a great impact on NO removal efficiency. The experimental results indicated that the gas–liquid reaction between NO and Fenton reagent solution was liquid-film controlled as NO inlet concentration exceeded 600ppm. And NO removal efficiency decreased with increasing reaction temperature. [Copyright &y& Elsevier]

Abstract: Dissolution rate of magnesium hydrate for wet flue gas desulfurization was measured by a pH-stat method. It was found that the dissolution rate of magnesium hydrate was controlled by mass transfer. As can be seen from the experimental results, the dissolution rate of magnesium hydrate increases with increasing reaction temperature and stirring speed. Lower pH value is favorable to the dissolution process of magnesium hydrate. And sulfate can promote the dissolution of magnesium due to the formation of bisulfate. [ABSTRACT FROM AUTHOR]

A graphited g -C 3 N 4 assembled with highly-dispersed nickel (HDNi@ g -C 3 N 4) exhibits accelerated reaction kinetics, excellent reversible capacity, and rate performance due to superior metallicity with increased density of states (DOS) at the Fermi energy level, narrowed energy gap between LUMO and HOMO level, and decreased positive Gibbs energy of polysulfide conversion. [Display omitted] • A graphited g -C 3 N 4 assembled with highly-dispersed nickel is designed as a catalyst of Li-S battery. • Exhibiting superior metallicity with increased density of states (DOS) at the Fermi energy level. • Narrowed energy gap contributes much to fast kinetics of negative electrons and positive Li+ ions. • Positive Gibbs energy significantly decreases for the prepared cathode materials. Lithium-sulfur (Li-S) batteries are promising next-generation energy storage devices due to high theoretical energy density and low-cost. Nevertheless, the practical applications are hindered by polysulfide shuttling effect, low electrical conductivity of sulfur, and slower conversion kinetics. Here, the graphited g -C 3 N 4 assembled with highly-dispersed nickel (HDNi@ g -C 3 N 4) is designed as a catalyst to accelerate the reaction kinetics of lithium polysulfide. The oxidized Ni sites of HDNi@ g -C 3 N 4 molecules significantly accommodate the orbital for the electron clouds of polysulfide by forming S n 2–‧‧‧Ni-N active site, thus efficiently improving redox kinetics and mitigating shuttle effects. Based on density functional theory (DFT) calculations, HDNi@ g -C 3 N 4 exhibits a superior metallicity with increased density of states (DOS) at the Fermi energy level. Then, the narrowed energy gap between the lowest unoccupied molecular orbital (LUMO) and highest occupied molecular orbital (HOMO) level contributes to the enhanced conductivity of catalyst molecular and fast combination between electrons and Li+ ions. Moreover, the positive Gibbs free energy change is significantly decreased for the HDNi@ g -C 3 N 4 cathode. The Li-S battery exhibits a high reversible capacity of 1, 271.6 mAh g−1 at 0.1 C and a high rate capacity of 571.96 mAh g−1 at 2.0 C, a preferable cycling stability with a capacity retention of 53 % even after 500 cycles at a 1.0 C, and an average decay rate of 0.733 % per cycle. [ABSTRACT FROM AUTHOR]

Objective To evaluate the efficacy and safety of uterine artery embolization (UAE) in the management of primary postpartum hemorrhage associated with placenta accreta. Methods We retrospectively reviewed the medical records of patients with placenta accreta between January 2010 and August 2014. Totally 18 women (mean age 30.8±4.2 years) of primary massive postpartum hemorrhage with diagnosis of placenta accrete received treatment of UAE after delivery. Images of DSA and medical records were reviewed. Technical success was defined as control of bleeding after embolization. The complications, control of hemorrhage and recurrent bleeding of the placenta left inside the uterus were retrospectively collected for assessment. Results All patients underwent transcatheter embolization of bilateral uterine arteries. The technical success rate of embolization was 100%. Bleeding was controlled in 17 of 18 patients (94%) during follow-up period (median 18 months, 3–31 months) without further bleeding recurred. One patient with placenta percreta undertook an emergent hysterectomy along with surgical bladder repair after UAE because of persistent uterine bleeding. Eight patients had postembolization syndrome and no other complications occurred. Conclusion Uterine artery embolization is an effective and safe treatment for the management of primary postpartum massive hemorrhage associated with placenta accreta. [ABSTRACT FROM AUTHOR]

Objective To evaluate the role of multidetector computed tomography-angiography (MDCTA) for management of life-threatening spontaneous retroperitoneal haemorrhage (SRH). Methods A retrospective analysis of the medical records of all SRH patients admitted to our hospital from January 1, 2005 to November 31, 2014 was performed. SRH was defined as unrelated to invasive procedures, surgery, trauma, abdominal tumor or aortic aneurysm. Life-threatening SRH was defined as hemodynamic instability with hypotension. Sixteen cases met the inclusive criteria. Patients' characteristics, clinical presentation, imaging of MDCTA, treatment modalities, morbidity, and follow-up data were analyzed. Results The group of 16 patients included 11 men and 5 women, with a mean age of 51.5±16.4 years. All patients underwent MDCTA scan examinations, and active contrast media (CM) extravasation were found in 9 patients. Angiography was performed for 8 patients in the CM extravasation group. Bleeding vessels were found in 7 patients who underwent successful embolization. One patient in the CM extravasation group did not undergo angiography and died of bleeding. Seven patients without active CM extravasation underwent conservative management. Bleeding was controlled for all these 7 patients, and 1 patient died of multiple organ failure. Fourteen patients survived from SRH were successfully discharged. One patient died of heart failure during follow-up. Conclusion MDCTA was useful in the diagnosis of SRH and proved to be predictive for the outcome of conservative treatment and early intervention. [ABSTRACT FROM AUTHOR]

Abstract: In order to simulate coal combustion and develop optimal and stable boiler control systems in real power plants, it is imperative to obtain the detailed information in coal combustion processes as well as to measure species contents in fly ash, which should be controlled and analyzed for enhancing boiler efficiency and reducing environmental pollution. The fly ash consists of oxides (SiO2, Al2O3, Fe2O3, CaO, and so on), unburned carbon, and other minor elements. Recently laser-induced breakdown spectroscopy (LIBS) technique has been applied to coal combustion and other industrial fields because of the fast response, high sensitivity, real-time and non-contact features. In these applications it is important to measure controlling factors without any sample preparation to maintain the real-time measurement feature. The relation between particle content and particle diameter is also one of the vital researches, because compositions of particles are dependent on their diameter. In this study, we have detected the contents of size-segregated particles using LIBS. Particles were classified by an Anderson cascade impactor and their contents were measured using the output of 1064nm YAG laser, a spectrograph and an ICCD camera. The plasma conditions such as plasma temperature are dependent on the size of particles and these effects must be corrected to obtain quantitative information. The plasma temperature was corrected by the emission intensity ratio from the same atom. Using this correction method, the contents of particles can be measured quantitatively in fixed experimental parameters. This method was applied to coal and fly ash from a coal-fired burner to measure unburned carbon and other contents according to the particle diameter. The acquired results demonstrate that the LIBS technique is applicable to measure size-segregated particle contents in real time and this method is useful for the analysis of coal combustion and its control because of its sensitive and fast analysis features. [Copyright &y& Elsevier]

Abstract: The absorption kinetics of NO into aqueous solutions of NaClO3/NaOH was investigated under different experimental conditions in a stirred tank reactor. It is proven that the absorption process is a fast pseudo-mth reaction. The reaction was found to be second-order with respect to NO and first-order with respect to NaClO3. The frequency factor and average activation energy of this reaction were 2.696×106 m3/(mols) and 13.88kJ/mol, respectively. The addition of NaOH to solutions of NaClO3 decreased the absorption rate of NO. And the absorption rate of NO increased with increasing reaction temperature. In this study, the flue gas flow rate almost had little effect on the absorption of NO. [ABSTRACT FROM AUTHOR]

Abstract: The total synthesis of isomer of didemnaketal A was achieved in 26 steps. The position of esters is switched at C7 and C8 with respect to their proposed position in natural didemnaketal A, which shows potent anti-HIV activity but so far has not been synthesized in the laboratory. Structural analysis of synthetic isomer of didemnaketal A indicates that the esters at C7 and C8 are correctly assigned, suggesting that the problems for the structural reassignment of natural didemnaketal A lie elsewhere. [Copyright &y& Elsevier]