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High inductive helical support provides a solution to controlling the alignment error of inner electrodes in magnetically insulated transmission lines (MITLs). Three-dimensional particle-in-cell simulations were performed to examine the current loss mechanism and the effects of structural parameters on electron flow in an MITL with a helical inductor. An empirical expression related to the ratio of electron current loss to anode current and the ratio of anode current to self-limited current was obtained. Electron current loss caused by helical inductor with different structures was displayed. The results indicate that the current loss in an MITL, near an inductive helical support, comprises both the inductor current and the electron current loss. The non-uniform structure and current of a helical inductor cause an abrupt change in the magnetic field near the helical support, which leads to anomalous behavior and current loss of electron flow. In addition, current loss in the inductive helical-supported MITL is negligible when the inductance of the support is sufficiently high. This work facilitates the estimation of electron current loss caused by the inductive helical support in MITLs.
Echinococcus granulosus sensu stricto (s.s.), Echinococcus multilocularis and Echinococcus canadensis are the common causes of human echinococcosis in China. An accurate species identification tool for human echinococcosis is needed as the treatments and prognosis are different among species. The present work demonstrates a method for the simultaneous detection of these three Echinococcus species based on multiplex polymerase chain reaction (mPCR). Specific primers of this mPCR were designed based on the mitochondrial genes and determined by extensive tests. The method can successfully detect either separated or mixed target species, and generate expected amplicons of distinct size for each species. Sensitivity of the method was tested by serially diluted DNA, showing a detection threshold as less as 0.32 pg for both E. granulosus s.s. and E. canadensis, and 1.6 pg for E. multilocularis. Specificity assessed against 18 other parasites was found to be 100% except weakly cross-react with E. shiquicus. The assay was additionally applied to 69 echinococcosis patients and 38 healthy persons, confirming the high reliability of the method. Thus, the mPCR described here has high application potential for clinical identification purposes, and can further provide a useful tool for evaluation of serology and imaging method.
The output performances of a bidirectional ring amplifier with twin pulses are demonstrated. Compared to the extraction efficiency of 32% for single-pulse injection, the extraction efficiency of stored energy for twin-pulse injection with bidirectional propagation is increased to 60%. The maximum output energies of the twin pulses are 347 mJ and 351 mJ, and the output energy of a single pulse is only 373 mJ under the same amplifier operating conditions. The experimental results show that the bidirectional ring amplifier with twin pulses can achieve a higher extraction efficiency of stored energy at a lower operating fluence, and has potential applications in high-power and high-energy laser facilities.
The preparation of three-dimensional honeycomb nitrogen-doped carbon materials (3D-HNCMs) which can be used as electrode materials for supercapacitors is reported. The composites with the 3D honeycomb structure exhibited better electrochemical performance, and the structure and properties were proved by various means, such as SEM, TEM, IR, N2 sorption, XRD and XPS. Used as electrode materials for supercapacitors in the KOH electrolyte, 3D-HNCMs displayed a significantly high specific capacitance (409 F/g at a current of 0.5 A/g). Moreover, the 3D-HNCM electrode exhibited superior electrochemical performance, such as excellent cycling stability (98% capacitance retention after 10,000 cycles), a maximum energy density of 15.37 W h/kg, a maximum power density of 40.3 kW/kg, and low equivalent series resistance (2.1 Ω). Particularly, the electrochemical characteristic of 3D-HNCMs could be attributed to the synergistic effect of a high surface area, unique microporous and mesoporous structure, and nitrogen atom doping. These carbon materials with unique structure are promising electrode materials for future supercapacitor application.
A 15-year-old teenager presented with a 2-month history of headache. Neurological examination was normal except for papilledema. Further lumbar puncture indicated intracranial hypertension (330 mm H2O). Brain magnetic resonance imaging (MRI) was normal but phase contrast-magnetic resonance venography (PC-MRV) (Figure 1(A)) suggested possible left transverse-sigmoid sinus thrombosis; subsequent contrast-enhanced 3D fat-saturated T1 volumetric isotropic turbo spin echo acquisition (VISTA) MRI (Figure 1(B)) confirmed the pathology. Hyper-coagulable panel results (including six steroid sex hormones, antithrombin III, protein C, protein S, lupus anticoagulant, and anticardiolipin antibodies) were all within normal range. In further examination, computed tomography (CT) venography images (Figure 1(C) and (D)) showed that the left jugular vein was compressed by the styloid process, consistent with Eagle syndrome.1 The patient who refused the recommended surgical treatment, however, chose anticoagulant therapy consisting of low-molecular weight heparin subcutaneous injection in addition to new oral anticoagulant. At 18-month follow-up, the patient reported no symptoms remained.
Whether borderline personality disorder (BPD) and bipolar disorder are the same or different disorders lacks consistency.
To detect whether grey matter volume (GMV) and grey matter density (GMD) alterations show any similarities or differences between BPD and bipolar disorder.
Web-based publication databases were searched to conduct a meta-analysis of all voxel-based studies that compared BPD or bipolar disorder with healthy controls. We included 13 BPD studies (395 patients with BPD and 415 healthy controls) and 47 bipolar disorder studies (2111 patients with bipolar disorder and 3261 healthy controls). Peak coordinates from clusters with significant group differences were extracted. Effect-size signed differential mapping meta-analysis was performed to analyse peak coordinates of clusters and thresholds (P < 0.005, uncorrected). Conjunction analyses identified regions in which disorders showed common patterns of volumetric alteration. Correlation analyses were also performed.
Patients with BPD showed decreased GMV and GMD in the bilateral medial prefrontal cortex network (mPFC), bilateral amygdala and right parahippocampal gyrus; patients with bipolar disorder showed decreased GMV and GMD in the bilateral medial orbital frontal cortex (mOFC), right insula and right thalamus, and increased GMV and GMD in the right putamen. Multi-modal analysis indicated smaller volumes in both disorders in clusters in the right medial orbital frontal cortex. Decreased bilateral mPFC in BPD was partly mediated by patient age. Increased GMV and GMD of the right putamen was positively correlated with Young Mania Rating Scale scores in bipolar disorder.
Our results show different patterns of GMV and GMD alteration and do not support the hypothesis that bipolar disorder and BPD are on the same affective spectrum.
Astrophysical collisionless shocks are amazing phenomena in space and astrophysical plasmas, where supersonic flows generate electromagnetic fields through instabilities and particles can be accelerated to high energy cosmic rays. Until now, understanding these micro-processes is still a challenge despite rich astrophysical observation data have been obtained. Laboratory astrophysics, a new route to study the astrophysics, allows us to investigate them at similar extreme physical conditions in laboratory. Here we will review the recent progress of the collisionless shock experiments performed at SG-II laser facility in China. The evolution of the electrostatic shocks and Weibel-type/filamentation instabilities are observed. Inspired by the configurations of the counter-streaming plasma flows, we also carry out a novel plasma collider to generate energetic neutrons relevant to the astrophysical nuclear reactions.
We present laboratory measurement and theoretical analysis of silicon K-shell lines in plasmas produced by Shenguang II laser facility, and discuss the application of line ratios to diagnose the electron density and temperature of laser plasmas. Two types of shots were carried out to interpret silicon plasma spectra under two conditions, and the spectra from 6.6 Å to 6.85 Å were measured. The radiative-collisional code based on the flexible atomic code (RCF) is used to identify the lines, and it also well simulates the experimental spectra. Satellite lines, which are populated by dielectron capture and large radiative decay rate, influence the spectrum profile significantly. Because of the blending of lines, the traditional
value are not applicable in diagnosing electron temperature and density of plasma. We take the contribution of satellite lines into the calculation of line ratios of He-
lines, and discuss their relations with the electron temperature and density.
Three types of multilayer flyer energy conversion elements (MFECEs) through integrating different laser pulse absorption/ablation layer of nano-film materials into a laser-driven flyer plates between thermal barrier of alumina and transparent substrate have been investigated in this study. The relationships among the velocity of flyer plates, initiation performance of hexanitrostilbene (HNS-IV), and initiation energy were analyzed, comparing with single-layer Al flyer plate. The photonics Doppler velocimetry and James criterion were utilized in the experiments to characterize the velocity of flyer plates and shock initiation of laser-driven flyer detonator, respectively. The surface reflectivity measurements of the Al, C/Al and Mg/Al layers were performed using laser reflectivity. HNS-IV without initiation was analyzed by scanning electron microscope and energy dispersive spectrometer. Caused by aluminum/alumina/aluminum (Al/Al2O3/Al) flyer plate, the residual fragments were found in the pit on the surface of charge. The results obtained were shows that three types of multilayer flyer plates can initiate HNS-IV successfully under the lower laser pulse energy, although all four kinds of flyer plates have successfully initiated HNS-IV with laser pulse energy in the range of 53.80–166.80 mJ. Changing the ablation layer structure and adding thermal insulation layer to the multilayer flyer plates, reduces the shock initiation laser pulse energy of HNS-IV to 53.80 mJ. The laser-driven flyer detonator has significant advantages in providing safety and reliability, especially in a strong electromagnetic environment. The MFECEs of laser-driven flyer detonator exhibited a high level of integration and proved to have promoted laser-driven energy coupling rate, which can significantly be used to improve the performance of the laser-driven flyer detonator in military and civilian applications.
Electrocatalytic water splitting for the production of H2 is increasingly becoming a significant method to mitigate the current energy crisis and environmental pollution. However, oxygen evolution reaction (OER), a slow four-electron progress, is the bottle neck of water splitting. Thus, developing new, low cost, and effective catalysts for OER is a research hotspot in material and energy resource fields. Therefore, the research of nonprecious, metal-based OER catalysts has been popular. In this work, it is validated that 3D hollow Co(OH)2 nanoflowers synthesized by a facile template-based strategy at room temperature are effective electrocatalysts for OER. The catalysts display high activity with a current density of 10 mA/cm2 at an overpotential of 310 mV and a small Tafel slope of 68.9 mV/dec in alkaline condition. It’s noteworthy that this material is stable for over 20 h of chronopotentiometry. This work offers a simple and promising way to prepare efficient and durable electrocatalysts.
A novel scheme for power-combined frequency tripler adopting 2N diodes is proposed in this work. Even mode coupled suspended substrate stripline is used to divide and recombine the input and output power. The circuits of the tripler are printed on both sides of the substrate, with N diodes on the front side and the other N diodes on the back side. The front diodes and back diodes are in anti-parallel connection, and DC biased separately to increase the bandwidth and power capacity. Three Q-band prototypes with two, four, and six diodes are fabricated and tested. The output compression powers at output frequency of 43.5 GHz for two/four/six-diode tripler are 9.2, 11, and 12 dBm, respectively. Power capacity is improved with the proposed tripler. Optimum DC bias is also discussed in this work, and it is found that it first increases with drive power, and then drops when large drive power applied because of the increased series resistance of the diode due to high junction temperature.
The CMP challenges for advanced technology nodes are discussed. Global and local uniformity challenges and their cumulative effects are presented. Uniformity improvements for advanced node integration were achieved through slurry, pad and platen optimization, innovative integration schemes, the reduction of incoming variation and the reduction of cumulative effects. We discuss reduction of typical CMP defect types. Defects resulting from simple mechanisms (foreign material, polish residues) and those resulting from chemical and physical interactions (corrosion, chemical attack, scratches, physical migration) and strategies for control are studied. Defectivity reduction measures include new post-CMP clean chemicals, new slurries and pads and reduction of incoming defectivity. Finally we discuss an observed tradeoff between good defectivity and good uniformity.
This article outlines the evolution of a rescue team in responding to adenovirus prevention with a deployable field hospital. The local governments mobilized a shelter hospital and a rescue team consisting of 59 members to assist with rescue and response efforts after an epidemic outbreak of adenovirus. We describe and evaluate the challenges of preparing for deployment, field hospital maintenance, treatment mode, and primary treatment methods. The field hospital established at the rescue scene consisted of a medical command vehicle, a computed tomography shelter, an X-ray shelter, a special laboratory shelter, an oxygen and electricity supply vehicle, and epidemic prevention and protection equipment. The rescue team comprised paramedics, physicians, X-ray technicians, respiratory therapists, and logistical personnel. In 22 days, more than 3000 patients with suspected adenovirus infection underwent initial examinations. All patients were properly treated, and no deaths occurred. After emergency measures were implemented, the spread of adenovirus was eventually controlled. An emergency involving infectious diseases in less-developed regions demands the rapid development of a field facility with specialized medical personnel when local hospital facilities are either unavailable or unusable. An appropriate and detailed prearranged action plan is important for infectious diseases prevention. (Disaster Med Public Health Preparedness. 2018;12:109–114)
A dense monolithic intermetallic Al3Ti alloy was successfully synthesized via reactive sintering in vacuum using TC4 alloy and pure aluminum foils with appropriate initial thickness. Energy dispersive spectroscopy (EDS), x-ray diffractometry (XRD), and scanning electron microscopy (SEM) were used to characterize the phase and microstructure of Al3Ti alloy. Ultrasonic measurement was performed to evaluate the physical property of Al3Ti alloy. Different thermal analysis, thermogravimetry (TG) and differential scanning calorimetry (DSC) were used to assess the thermal property of Al3Ti alloy. The compressive tests were carried out on a universal load frame to determine the mechanical properties, including the compressive strength and failure strain of the fabricated intermetallic Al3Ti alloy. The current results indicated that the density of Al3Ti alloy is slightly higher than the theoretical density, the average Young's modulus is lower than the theoretical value. A trace of aluminum in Al3Ti alloy was detected, which is distinctly affected on the density, Young's modulus and mechanical properties of this titanium aluminide alloy. The stress–strain curves of Al3Ti alloy shows a linear elastic behavior without any plastic deformation, and the fracture features are the mixed fracture of transgranular and intergranular. Some other fundamental physical and mechanical properties of the Al3Ti alloy were also obtained in the present study.
SG-III laser facility is now the largest laser driver for inertial confinement fusion research in China. The whole laser facility can deliver 180 kJ energy and 60 TW power ultraviolet laser onto target, with power balance better than 10%. We review the laser system and introduce the SG-III laser performance here.
Widespread loess deposits in the Central Shandong Mountains yield valuable paleoclimatic records for this currently semi-humid monsoonal region of northern China. The grain-size distribution and major element composition for bulk samples and two grain-size fractions (< 20 and 20–63 μm) for the loess in the Central Shandong Mountains were compared with loess from the Chinese Loess Plateau and sediment from the Yellow River to help determine its provenance. The presence of a significant percentage of medium- and coarse-silt, and the difference in relatively immobile major element ratios of TiO2/Al2O3 and K2O/Al2O3 for the < 20 and 20–63 μm fractions, suggests that sediment that forms the loess deposits in the Central Shandong Mountains was not blown directly from the northern deserts of China as is the case for the loess deposits of the Chinese Loess Plateau. Rather, this suggests that sediments exposed during glacial times on the North China fluvial plain, including the floodplain of the Yellow River, were the major dust source for the loess in the Central Shangong Mountains. In addition, the wide distribution of perimontane loess in the Central Shandong Mountains region indicates the occurrence of strengthened local aridification during glacial times since the middle Pleistocene.
This is a case-control study to investigate the prevalence, characteristics, and risk factors of pain in patients with Parkinson's disease (PD).
A total of 200 PD patients from eastern China were enrolled in our study. Accordingly, 200 healthy elderly adults were recruited as controls. The characteristics of pain were collected by using the Visual Analog Scale, Brief Pain Inventory (BPI), SF-36 Bodily Pain Scale, Unified Parkinson's Disease Rating Scale, Hoehn–Yahr Scale (H-Y), Hamilton Depression Scale, and Leeds Assessment of Neuropathic Symptoms and Signs.
Of the 200 PD patients, pain was complained by 106 patients (53%). According to the SF-36 Bodily Pain Scale, pain morbidity in PD patients was significantly higher than in the control group. The average pain during last 24 h measured by the BPI was 2.67. About 76% of PD patients were found to have one pain type, 21.7% were having two pain types, and 1.9% had three pain types. Further, 69.8% of these patients were presented with musculoskeletal pain, 4.7% with dystonic pain, 22.6% with radicular-neuropathic pain, 20.8% with central neuropathic pain, and 9.4% with akathisia pain. The onset age and depression were the most significant predictors of pain in PD patients (p < 0.05). However, there was no significant association between pain and gender, age, disease duration, or severity of the disease. Only 5.7% of PD patients with pain received treatment in this study.
Pain is frequent and disabling, independent of demographic and clinical variables, and is significantly more common in PD patients.
To assess correlations between cruciferous vegetable intake and urinary isothiocyanate (ITC) level, in addition to glutathione S-transferase (GST) genotypes and other individual factors.
The study included cohort participants whose urinary ITC levels had been previously ascertained. Urinary ITC was assessed using HPLC. Usual dietary intake of cruciferous vegetables was assessed using a validated FFQ and total dietary ITC intake was calculated. Recent cruciferous vegetable intake was determined. GST genotypes were assessed using duplex real-time quantitative PCR assays. Spearman correlations were calculated between the covariates and urinary ITC levels and linear regression analyses were used to calculate the mean urinary ITC excretion according to GST genotype.
Urban city in China.
The study included 3589 women and 1015 men from the Shanghai Women’s and Men’s Health Studies.
Median urinary ITC level was 1·61 nmol/mg creatinine. Self-reported usual cruciferous vegetable intake was weakly correlated with urinary ITC level (rs=0·1149; P<0·0001), while self-reported recent intake was more strongly correlated with urinary ITC (rs=0·2591; P<0·0001). Overall, the GST genotypes were not associated with urinary ITC level, but significant differences according to genotype were observed among current smokers and participants who provided an afternoon urine sample. Other factors, including previous gastrectomy or gastritis, were also related to urinary ITC level.
The study suggests that urinary secretion of ITC may provide additional information on cruciferous vegetable intake and that GST genotypes are related to urinary ITC level only in some subgroups.
In this paper, a class of novel four Degrees of Freedom (DOF) non-overconstrained parallel mechanisms with large rotational workspace is presented based on screw theory. First, the conflict between the number of independent constraints applied on the moving platform and the number of kinematic limbs for 4-DOF non-overconstrained parallel mechanism is identified. To solve this conflict, the platform partition method is introduced, and two secondary platforms are employed in each of the parallel mechanisms. Then, the motion requirements of the secondary platforms are analyzed and all the possible kinematic chains are enumerated. The geometrical assembly conditions of all possible secondary limbs are analyzed and some typical non-overconstrained parallel mechanisms are generated. In each of the parallel mechanisms, a planetary gear train is used to connect both of the secondary platforms. The large rotational workspace of the moving platform is obtained due to the relative motion of the two secondary platforms. Finally, the kinematics analysis of a typical parallel mechanism is conducted.