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Guangxin Hu,1,&ast; Xijuan Qi,1,&ast; Ben Li,1 Ting Ge,1 Xi Li,1 Zhijun Liu,1 Jiaxing Li,1 Xuemei Zhang,1 YinPing Li,1 Shichang Zhang,1 Yajuan Wang,2 Tingting Zhao,3 Botao Zhang,1 Qingbin Xu1 1Department of Cardiology, General Hospital of Ningxia Medical University, Yinchuan, 750002, People’s Republic of China; 2Department of Pharmacy, General Hospital of Ningxia Medical University, Yinchuan, 750002, People’s Republic of China; 3Department of Respiratory Medicine, General Hospital of Ningxia Medical University, Yinchuan, 750002, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Guangxin Hu, Email hugx8911_ecg@163.comObjective: To assess the effectiveness and safety of an IVUS-guided rotational atherectomy (RA) percutaneous coronary intervention (PCI) in chronic renal patients with complex coronary calcification who are at risk for contrast-related acute kidney injury (AKI).Methods: From October 2018 to October 2021, 48 patients with chronic renal disease who were receiving PCI with RA at the General Hospital of NingXia Medical University were informed for data collection for this research. They were randomly assigned to the IVUS-guided RA group and the Standard RA group, which did not use IVUS. According to a clinical expert consensus document on rotational atherectomy in China, both PCI procedures were performed. The intravascular ultrasound (IVUS) results from the study group were used to describe the morphology of the lesion and to guide the selection of burrs, balloons, and stents. IVUS and angiography were used to evaluate the outcome in the end. IVUS-guided RA PCI and Standard RA PCI groups’ effects and results were contrasted.Results: There were no appreciable differences in the clinical baseline characteristics between the IVUS-guided RA PCI group and the Standard RA PCI group. The average estimated glomerular filtration rate (eGFR) of two groups was (81.42 ± 20.22 vs 82.34 ± 22.19) mL/min/1.73 m2. Most of them (45.8% vs 54.2%) was in stage 60– 90 mL/min/1.73m2. When compared to the standard RA PCI group, RA in IVUS-Guided group was more performed electively (87.5% vs 58.3%; p = 0.02). The IVUS-guided RA PCI group was associated with shorter fluoroscopy time (20.6 ± 8.4 vs 36 ± 22; p< 0.01) and less contrast amount (32 ± 16 vs 184 ± 116mL; p< 0.01) than Standard-RA group. Five patients in the Standard RA PCI group developed contrast-induced nephropathy, which was 5 times than the IVUS-guided RA PCI group (20.8% VS 4.1%; p=0.19).Conclusion: In chronic renal patients with complex coronary calcification, an IVUS-guided RA PCI technique is effective and safe. It can also lower the volume of contrast and perhaps the incidence of contrast-related AKI.Keywords: rotational atherectomy, chronic renal disease, contrast-associated acute kidney injury, intravascular ultrasound

BackgroundDietary antioxidants have long been thought to be likely to prevent the development of gliomas. Previous studies have reported vitamin A, C, and E protective effects against gliomas. B vitamins, one of the main vitamins in the diet, are closely related to human health, but the association with gliomas has rarely been reported.ObjectiveThis study aimed to evaluate the relationship between five B vitamins and glioma.MethodsIn this Chinese population-based case–control study, 506 glioma cases and 506 matched (age and sex) controls were included. The dietary intake of study participants was assessed using a valid 111-item food frequency questionnaire. The intake of five B vitamins was calculated based on participants’ dietary information from the food frequency questionnaire. The logistic regression model was used to examine the association between B vitamins and glioma, and the restriction cubic spline evaluated the dose–response relationship between the two.ResultsAfter adjusting for confounding factors, thiamine (OR = 0.09, 95%CI: 0.05–0.20), riboflavin (OR = 0.12, 95%CI: 0.06–0.25), nicotinic acid (OR = 0.24, 95%CI: 0.12–0.47), folate (OR = 0.07, 95%CI: 0.03–0.15) and biotin (OR = 0.14, 95%CI: 0.07–0.30) in the highest tertile were associated with a significantly decreased risk of glioma compared with the lowest tertile. The results of thiamine and biotin in glioma with different pathological types and grades were different. The restricted cubic spline function showed significant dose–response relationships between the intake of five B vitamins and the risk of glioma. When B vitamins exceeded a specific intake, the risk of glioma did not change.ConclusionOur study suggests that higher dietary intake of thiamine, riboflavin, nicotinic acid, and folate are associated with a decreased risk of glioma, but the results of biotin are not consistent among different populations. In the future, prospective studies should be conducted better to validate the effects of B vitamins on gliomas.

Olfactory neuroblastoma is a rare neoplasm that usually presents in the upper nasal cavity. Although its prognosis is highly unfavorable, effective treatment options are still lacking. Moreover, there is no standard treatment for patients with olfactory neuroblastoma that progressed to leptomeningeal carcinomatosis. Here we report an uncommon case of a 59-year-old woman who was diagnosed with olfactory neuroblastoma and leptomeningeal carcinomatosis. For a direct delivery of the drugs to the tumor, and to avoid the impact of lumbar puncture on the patient’s quality of life, the intravenous chemotherapy plus intrathecal administration of MTX via an Ommaya reservoir was chosen. The results were striking, with the disappearance of tumor cells in the cerebrospinal fluid and the relief of the patient’s symptoms with PR. Our result indicates that chemotherapy via an Ommaya reservoir offers a new potential therapy for patients with meningeal metastases.

The catalytic performances of different commercial cobalt oxides(Co x O y , i.e., Co2O3, Co3O4, and CoO) for peroxymonosulfate(PMS) activation in dye degradation were compared in this study. The CoO/PMS system exhibited the highest catalytic oxidation performances with more than 96% methylene blue(MB) removal at 90 min. The concentration of dissolved cobalt ions from CoO was 1.474 mg/L at neutral pH and 5.231 mg/L at acidic pH at 90 min which accounted for the high MB removal and CoO activated PMS homogeneously compared to the associated CoSO4/PMS. Co3O4 and Co2O3 exhibited similar catalytic performances and characteristics. The MB removal in Co3O4/PMS and Co2O3/PMS system were more than 88% at neutral pH and over 64% at acidic pH, respectively, in 90 min. The concentration of dissolved cobalt ions from Co3O4 and Co2O3 was less than 0.018 mg/L at neutral pH and 0.036 mg/L at acidic pH at 90 min. The MB removal achieved by Co3O4/PMS and Co2O3/PMS were approximately three times higher than that achieved by their associated CoSO4/PMS systems and the heterogeneous catalysis played a principal role in the processes. According to scavenger experiments, the contributions of the hydroxyl radicals in the MB degradation were negligible compared to sulfate radicals in the CoO/PMS system. Hydroxyl radicals contributed one-third or more and sulfate radicals were the dominant oxidizing species in the Co3O4/PMS and Co2O3/PMS systems. Co x O y could also effectively activate PMS to generate free radicals for degradation of other dyes. The dyedegradation processes in Co3O4/PMS, Co2O3/PMS and CoSO4/PMS systems followed pseudo-first-order kinetic model and dye degradation rates in different systems were also compared.

Natural convection boiling in channel with Arc-Shaped will be encountered in the IVR-ERVC (In-Vessel Retention measure by External Reactor Vessel Cooling) system in nuclear power plant under severe accident. The flow and heat transfer characters in this situation is simulated by flow boiling of deionized water in an inclined rectangular channel under low flow rates. This paper aims to separate various parameters (such as orientation, mass flow rate and inlet quality, etc.) to investigate their individual effects on heat transfer coefficient (HTC) in a rectangular channel with cross section of 17 mm × 10 mm. By using a preheater at the inlet of the rectangular channel, the inlet quality could be controlled and the two-phase flow situation could be observed before the fluids entering into the main heater region on one side of the channel wall in downstream. Thus the characteristics of HTC on the main heater could be investigated at different flow patterns. The channel orientations vary from 15 to 90°, the mass flow rates vary from 110 to 288 kg/(m2s) and the qualities vary from 0.003 to 0.036, respectively. Experimental results show that the mass flow rate and quality effects on the HTC are very weak in this study. However, the orientation angle effect on HTC shows an transition region within 45°~60°, while it slowly changes when the orientation angle is smaller than 45° and bigger than 60°. Such tendency could be well formulated by the error function. Compared with different empirical formulas of saturated boiling HTC, it is found that the Liu & Winterton correlation can well predict the experimental HTC results in 90° orientation channel. Based on such correlation and coupled with the error function, a new model was developed by considering the orientation effect, which has an error of ±15% comparing with the experimental data.

This paper presents a probabilistic path planning method for robot target search to reduce the expected-time cost in uncertain environments. Considering the validity of the manual setting probability decreases with time, a model of attenuation and growth is constructed to update the probability information of observation points. Because different direction may lead to different expected-time in the same loop, a direction choosing method is used to improve the performance of this planning method. Then, a double-level planning strategy is designed. At the top level, a heuristic sequence planning algorithm is employed to generate the sequence of observation points. At the lower level, the Artificial Potential Field (APF) is applied to plan the optimal path between every two observation points. Simulations demonstrated that this method can reduce the expected-time in repeated target search tasks by increasing a little computational cost.

External reactor vessel cooling (ERVC) is the key technology for In-Vessel Retention (IVR) to ensure the safety of a nuclear power plant (NPP) under severe accident conditions. The thermal margin of nucleate boiling heat transfer on the reactor pressure vessel (RPV) lower head is important for ERVC and of wide concern to researchers. In such boiling heat transfer processes, the reactor vessel wall inclination effect on the heat transfer coefficient (HTC) and critical heat flux (CHF) should be considered. In this study, experiments were performed to investigate the effects of heater material and surface orientation on the HTC and CHF of nucleate boiling. Copper and stainless steel (SS) surfaces were used to perform boiling tests under atmosphere pressure. The orientation angle of both boiling surfaces were varied between 0° (upward) and 180° (downward). The experimental results show that the surface orientation effects on the HTC is slight for both the copper surface and the SS surface. In addition, the relationship of measured CHF values with the inclination angles was obtained and it shows that the CHF value changes little as the inclination angle increases from 0° to 120° but it decreases rapidly as the orientation angle increases towards 180° for both boiling surfaces. The material effect on CHF is also observed and the copper surface has higher CHF value than the SS surface. Based on the experimental data, a correlation for CHF prediction is developed which includes both the surface orientation effect and the heater material effect.Copyright © 2017 by ASME

A physical, hydrochemical and isotopic evaluation of springs in Beijing was conducted in 2009 to reveal apparent changes in the properties of those springs. The results showed that most of the 2nd class springs and more than 50 % of the 1st class springs recorded in the early 1980s were depleted, while the discharges of existing springs have also decreased sharply. In addition, the majority of springs were of the HCO3–Ca–Mg type and good water quality, with the quality indices changing slightly compared to those recorded 30 years ago. The abundances of 2H, 18O, and 3H in the springs indicated that most of the springs were of meteoric origin with a relatively close connection to modern atmospheric precipitation. As a result, the springs have a relatively strong renewability within a shallow circulation.

Although there is an obvious relationship between the Chinese Postman Problem (CPP) and the path-planning problem for multiple target-search tasks by a robot, no attempts have been made so far to connect the two. A novel map transformation framework (MTF) is proposed in this paper. With MTF, a feature map or a topological map can be converted into a standard topological map on which many graph-search algorithms suitable for CPP can be employed to carry out path planning for multiple target search. Theoretical analysis proves that the route generated by this approach is optimal. Both simulation results and experiments indicate that the MTF-based algorithm is better than several other target-search algorithms. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

In the control of inverter power system, with reference to the dq transform in three-phase inverter control system, a control method of single-phase power inverter system based on lead signal and dq transform is proposed. In this method, the αβ frame is constructed by the physical “Real Circuit” and the second “Imaginary Orthogonal Circuit”, which is constituted by the 90 degree lead signal, thus the control scheme based on dq transform is realized. Simulation model based on dq transform is constructed in the simulink of MATLAB, the effectiveness and viability of the method is verified by the simulation and experiment results.

Under shock pressures up to 210 GPa, we measured the refractive index of sapphire at a wavelength of 1550 nm by performing plate impact experiments in order to investigate its refractive-index change behaviors and phase transitions along the Hugoniot state. There were two discontinuities in the refractive index at ∼65 to 92 GPa and ∼144 to 163 GPa, respectively. Moreover, above the Hugoniot elastic limit, the pressure dependence of the refractive index was divided into three segments, and there were large differences in their pressure-change trends: the refractive index decreased evidently with pressure in the first segment (∼20 to 65 GPa), remained nearly constant from ∼92 to ∼144 GPa in the second segment, and obviously increased with pressure in the last segment (∼163 to 210 GPa). Our first-principles calculations suggest that the observed discontinuities were closely related to the corundum-Rh2O3(II) and Rh2O3(II)-CaIrO3 structural transitions, and the shock-induced vacancy point defects could be one ...

Hierarchical nanostructures with much increased surface-to-volume ratio have been of significant interest for prototypical gas sensors. Herein we report a novel resistive gas sensor based on TiO2/V2O5 branched nanoheterostructures fabricated by a facile one-step synthetic process, in which well-matched energy levels induced by the formation of effective heterojunctions between TiO2 and V2O5, a large Brunauer-Emmett-Teller surface area and complete electron depletion for the V2O5 nanobranches induced by the branched-nanofiber structures are all beneficial to the change of resistance upon ethanol exposure. As a result, the ethanol sensing performance of this device shows a lower operating temperature, faster response/recovery behavior, better selectivity and about seven times higher sensitivity compared with pure TiO2 nanofibers. This study not only confirms the gas sensing mechanism for performing enhancement of branched nanoheterostructures, but also proposes a rational approach to the design of nanostructure-based chemical sensors with desirable performance.

Aimed at the mobile manipulator of which with a 6-DOFs manipulator mounted on the platform, the self-restriction as well as the redundant problem of the whole system are analyzed systematically,, and the standard D-H method is used to establish the forward kinematics model of the manipulator. Doing by certain kind of targets, the self-restriction of the whole system is taken into account, we have analyzed the inverse kinematics of the system using the conception of working room, and a reasonable and effective plan for the freedom distribution is brought forward, also the grasp motion to the target is realized. Experiment results are presented to show the effectiveness of the proposed approach.

A general expression for the spectrum of the DC-link capacitor voltage in the cascaded multilevel STATCOM is presented, and to predict the amplitude and frequency of the voltage harmonic components produced by balanced AC power voltage and current. The computation is developed using the switching functions approach, relating DC-link current, SPWM control pulse and the output AC current. Especially, the 2-th voltage harmonic is discussed in detail. Consideration of the voltage ripple, the required capacitance value and the voltage reference value are presented.

We design a Hankel's filter on the basis of detailed discussion of the techniques of integral of 0- and 1-order Bessel's function, and give the numerical examples together with the results of program operation in transient electromagnetic methods (TEM) theory.

We perform the integral of the double Bessel function in TEM theory by dividing the integral region with zero points, and give the results of the double Bessel function integral.