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Three-dimensional graphene (3D-GN)/Cu/Fe3O4 composite support materials were synthesized by a modified chemical reduction method using graphene oxide precursor. A 3D-GN/Cu/Fe3O4 biosensor was prepared by coating the electrode with laccase. The electrochemical properties of the biosensor were investigated by cyclic voltammetry (CV) and differential pulse voltammetry using potassium ferricyanide, phosphate-buffered saline (PBS) solution, and bisphenol A (BPA) solution. The current response of 3D-GN/Cu/Fe3O4 biosensors presents a remarkable sensitivity based on CV. The linear range of BPA is 7.2–18 μM using differential pulse voltammetry in PBS solution (pH = 4.0). A linear fitting equation of the laccase biosensor was observed for the current response as a function of BPA concentration. The detection limit was decreased to 1.7 μM. The detection approach herein turns out to be highly sensitive, has a wide linear range, and exhibits excellent stability.
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.
Although the streaked optical pyrometer (SOP) system has been widely adopted in shock temperature measurements, its reliability has always been of concern. Here, two calibrated Planckian radiators with different color temperatures were used to calibrate and verify the SOP system by comparing the two calibration standards using both multi-channel and single-channel methods. A high-color-temperature standard lamp and a multi-channel filter were specifically designed for the measurement system. To verify the reliability of the SOP system, the relative deviation between the measured data and the standard value of less than 5% was calibrated out, which demonstrates the reliability of the SOP system. Furthermore, a method to analyze the uncertainty and sensitivity of the SOP system is proposed. A series of laser-induced shock experiments were conducted at the ‘Shenguang-II’ laser facility to verify the reliability of the SOP system for temperature measurements at tens of thousands of kelvin. The measured temperature of the quartz in our experiments agreed fairly well with previous works, which serves as evidence for the reliability of the SOP system.
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.
Computerized cognitive remediation therapy (CCRT) is generally effective for the cognitive deficits of schizophrenia. However, there is much uncertainty about what factors mediate or moderate effectiveness and are therefore important to personalize treatment and boost its effects.
In total, 311 Chinese inpatients with Diagnostic and Statistical Manual of Mental Disorders-IV schizophrenia were randomized to receive CCRT or Active control for 12 weeks with four to five sessions per week. All participants were assessed at baseline, post-treatment and 3-month follow-up. The outcomes were cognition, clinical symptoms and functional outcomes.
There was a significant benefit in the MATRICS Consensus Cognitive Battery (MCCB) total score for CCRT (F1,258 = 5.62; p = 0.02; effect size was 0.27, 95% confidence interval 0.04–0.49). There were no specific moderators of CCRT improvements. However, across both groups, Wisconsin Card Sort Test improvement mediated a positive effect on functional capacity and Digit Span benefit mediated decreases in positive symptoms. In exploratory analyses younger and older participants showed cognitive improvements but on different tests (younger on Symbol Coding Test, while older on the Spatial Span Test). Only the older age group showed MSCEIT benefits at post-treatment. In addition, cognition at baseline negatively correlated with cognitive improvement and those whose MCCB baseline total score was around 31 seem to derive the most benefit.
CCRT can improve the cognitive function of patients with schizophrenia. Changes in cognitive outcomes also contributed to improvements in functional outcomes either directly or solely in the context of CCRT. Age and the basic cognitive level of the participants seem to affect the cognitive benefits from CCRT.
Schizophrenia is a complex mental disorder with high heritability and polygenic inheritance. Multimodal neuroimaging studies have also indicated that abnormalities of brain structure and function are a plausible neurobiological characterisation of schizophrenia. However, the polygenic effects of schizophrenia on these imaging endophenotypes have not yet been fully elucidated.
To investigate the effects of polygenic risk for schizophrenia on the brain grey matter volume and functional connectivity, which are disrupted in schizophrenia.
Genomic and neuroimaging data from a large sample of Han Chinese patients with schizophrenia (N = 509) and healthy controls (N = 502) were included in this study. We examined grey matter volume and functional connectivity via structural and functional magnetic resonance imaging, respectively. Using the data from a recent meta-analysis of a genome-wide association study that comprised a large number of Chinese people, we calculated a polygenic risk score (PGRS) for each participant.
The imaging genetic analysis revealed that the individual PGRS showed a significantly negative correlation with the hippocampal grey matter volume and hippocampus–medial prefrontal cortex functional connectivity, both of which were lower in the people with schizophrenia than in the controls. We also found that the observed neuroimaging measures showed weak but similar changes in unaffected first-degree relatives of patients with schizophrenia.
These findings suggested that genetically influenced brain grey matter volume and functional connectivity may provide important clues for understanding the pathological mechanisms of schizophrenia and for the early diagnosis of schizophrenia.
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.
Robots often need to accomplish some complex tasks such as surveillance, response and obstacle avoidance. In this paper, a dynamic search method is proposed to generate optimal robot trajectories satisfying complex task requirement in uncertain environment. The LTL-A* algorithm is presented to generate a global optimal path and the A* algorithm is provided to modify the global optimal path. The task is specified by a linear temporal logic (LTL) formula, and a weighted transition system according to the known information in uncertain environment is modeled to describe the robot motion. Subsequently, a product automaton is constructed by combining the transition system with the task requirement. Based on the product automaton, the LTL-A* algorithm is proposed to generate a global optimal path. The local path planning based on the A* algorithm is employed to deal with the environment change during the process of tracking the global optimal path for the robot. The results of the simulation and experiments show that the proposed method can not only meet the complex task requirement in uncertain environment but also improve the search efficiency.
A compact high-isolation power divider with bandpass response and high-frequency selectivity is presented in this letter. Two dual-mode resonators are used to realize filtering response. The circuit size of the proposed power divider can be reduced by using dual-mode capacitance loaded square meander loop resonators. Due to capacitive load, the resonator can exhibit slow-wave characteristics, which can be utilized to suppress harmonics and reduce size. The simulated and measured results show reasonable agreement.
The aim of the study was to investigate any association between extrauterine growth restriction (EUGR) and intestinal flora of <30-week-old preterm infants. A total of 59 preterm infants were assigned to EUGR (n=23) and non-EUGR (n=36) groups. Intestinal bacteria were compared by using high-throughput sequencing of bacterial rRNA. The total abundance of bacteria in 344 genera (7568 v. 13,760; P<0.0001) and 456 species (10,032 v. 18,240; P<0.0001) was significantly decreased in the EUGR group compared with the non-EUGR group. After application of a multivariate logistic model and adjusting for potential confounding factors, as well as false-discovery rate corrections, we found four bacterial genera with higher and one bacterial genus with lower abundance in the EUGR group compared with the control group. In addition, the EUGR group showed significantly increased abundances of six species (Streptococcus parasanguinis, Bacterium RB5FF6, two Klebsiella species and Microbacterium), but decreased frequencies of three species (one Acinetobacter species, Endosymbiont_of_Sphenophorus_lev and one Enterobacter_species) compared with the non-EUGR group. Taken together, there were significant changes in the intestinal microflora of preterm infants with EUGR compared to preterm infants without EUGR.
In order to improve the damage threshold and enlarge the aperture of a laser beam shaper, photolithographic patterning technology is adopted to design a new type of liquid crystal binary mask. The inherent conductive metal layer of commercial liquid crystal electro-optical spatial light modulators is replaced by azobenzene-based photoalignment layers patterned by noncontact photolithography. Using the azobenzene-based photoalignment layer, a liquid crystal binary mask for beam shaping is fabricated. In addition, the shaping ability, damage threshold, write/erase flexibility and stability of the liquid crystal binary mask are tested. Using a 1 Hz near-IR (1064 nm) laser, the multiple-shot nanosecond damage threshold of the liquid crystal mask is measured to be higher than
. The damage threshold of the azobenzene-based photoalignment layer is higher than
under the same testing conditions.
A high-power, Joule-class, nanosecond temporally shaped multi-pass ring laser amplifier system with two neodymium-doped phosphate glass (Nd:glass) laser heads is demonstrated. The laser amplifier system consists of three parts: an all-fiber structure seeder, a diode-pumped Nd:glass regenerative amplifier and a multi-pass ring amplifier, where the thermally induced depolarization of two laser heads is studied experimentally and theoretically. Following the injection of a square pulse with the pulse energy of 0.9 mJ and pulse width of 6 ns, a 0.969-J high-energy laser pulse at 1 Hz was generated, which had the ability to change the waveform arbitrarily, based on the all-fiber structure front end. The experimental results show that the proposed laser system is promising to be adopted in the preamplifier of high-power laser facilities.
Laves phase plays a positive role in improving the strength of high-entropy alloys (HEAs); Nb and Ti elements have potential to promote Laves phase formation in some HEAs. For improving the strength of the face-centered cubic (FCC) CoCrFeMnNi HEA, a series of (CoCrFeMnNi)100−xNbx (atomic ratio: x = 0, 4, 8, 12, 16) and (CoCrFeMnNi)100−xTix (atomic ratio: x = 0, 2, 4, 6, 8, 12) HEAs were prepared by melting. The effects of Nb and Ti on the microstructure evolution and compressive properties of the CoCrFeMnNi HEAs were investigated. For (CoCrFeMnNi)100−xNbx HEAs, the second-phase (Laves and σ phase) volume fraction increased from 0 to 42%. The yield strength also increased gradually from 202 to 1010 MPa. However, the fracture strain decreased from 60% (no fracture) to 12% with increasing Nb content. For (CoCrFeMnNi)100−xTix HEAs, the yield strength increased from 202 to 1322 MPa. The Laves phase volume fraction also increased from 0 to 27%. However, the fracture strain decreased from 60% (no fracture) to 7.5% with increasing Ti content. Addition of Nb and Ti has a good effect on improving the strength of FCC CoCrFeMnNi HEA.
The ultra-wideband bandpass-response power divider with high-frequency selectivity is presented in this paper. This power divider consists of an impedance transformer, a filter network, and two isolation resistors. In order to realize the ultra-wideband filtering performance, parallel coupling lines and parallel open-circuit branches are applied to the second impedance converter. A resistor is added to the ends of the coupling lines to achieve good isolation and output return loss. The equivalent-circuit method is employed to analyze the presented power divider. The power divider, working at 3.45–8.29 GHz, is designed and fabricated. Two transmission zeros are generated at 2.8 and 9 GHz, respectively, and the out-of-band suppression is >13 dB. The measured results are in good agreement with the simulation ones.
A modified compact Y-junction substrate-integrated waveguide (SIW) four-way power divider (PD)/combiner is proposed in this paper. The proposed approach is based on the traditional Y-junction waveguide. By using direct transition structure from SIW to half-mode SIW, four-way PD that provides equal power split to all four output ports is achieved. The even- and odd-mode equivalent circuits are given to analyze and design the PD. The measured results validate the proposed design methodology and show good agreement with the simulation results. The measured 17 dB return loss bandwidth and 1.2 dB insertion loss bandwidth of this four-way PD are both about 2.5 GHz.
The characteristics and mechanism for unsteady shock train motions were experimentally studied in a constant-area rectangular duct. High-speed Schlieren techniques and high-frequency pressure measurements were utilized in this research. The results show that the shock train undergoes periodical motions in response to downstream periodical excitations. The mechanism for unsteady shock train motions is that the shock train keeps changing its moving speed to change the relative Mach number ahead of shock train to match the varying back-pressure condition. It can be found that the unsteady shock train motion can be predicted well with a theoretical model, which is based on this mechanism. A correlation between the amplitude of shock train motions and some flow parameters was illustrated using an analytical equation, which was confirmed by the experimental results.
We demonstrate a laser diode end-pumped helium gas-cooled multislab Nd:glass laser amplifier. The design and thermal management of the proposed laser amplifier are discussed. The thermally induced wavefront aberration of the slabs was also measured and compared with simulation results. A small-signal single-pass longitudinal gain of 1.8 was measured with a pump energy of 7.3 J. With an injected seed energy of 0.6 mJ, the output energy from the amplifier reached 0.5 J at 0.2 Hz and 0.43 J at 0.5 Hz in a multipass extraction geometry, thus demonstrating the feasibility of diode-pumped, high-energy lasers with direct gas cooling.
In this paper, a response model of an Unmanned Surface Vehicle (USV) with a pod-like propulsion device is established. To improve the robustness of motion control in heavy sea states, an integrated nonlinear feedback course-keeping controller is proposed. First, to establish a response model of a USV with pod-like propulsion, model parameters are obtained by the method of system identification, then an integrated nonlinear feedback control strategy is proposed. The essence of this method is to make the original error signal pass through a nonlinear function, and then the output of this function is used to replace the original error signal. Simulation results show that under ordinary sea states, nonlinear feedback can save up to 34.5% of energy used compared with standard feedback methods; under heavy sea states, this can rise to 40.8%. A set of field experiments were carried out with a USV with pod-like propulsion. Results show that under heavy sea states, the test USV can maintain the target course well, which proves the correctness of the model and the robustness of the proposed method.
SCN5A encodes sodium-channel α-subunit Nav1.5. The mutations of SCN5A can lead to hereditary cardiac arrhythmias such as the long-QT syndrome type 3 and Brugada syndrome. Here we sought to identify novel mutations in a family with arrhythmia.
Genomic DNA was isolated from blood of the proband, who was diagnosed with atrial flutter. Illumina Hiseq 2000 whole-exome sequencing was performed and an arrhythmia-related gene-filtering strategy was used to analyse the pathogenic genes. Sanger sequencing was applied to verify the mutation co-segregated in the family.
Results and conclusions
A novel missense mutation in SCN5A (C335R) was identified, and this mutation co-segregated within the affected family members. This missense mutation was predicted to result in amplitude reduction in peak Na+ current, further leading to channel protein dysfunction. Our study expands the spectrum of SCN5A mutations and contributes to genetic counselling of families with arrhythmia.
On August 12, 2015, a hazardous chemical explosion occurred in the Tianjin Port of China. The explosions resulted in 165 deaths, 8 missing people, injuries to thousands of people. We present the responses of emergency medical services and hospitals to the explosions and summarize the lessons that can be learned.
This study was a retrospective analysis of the responses of emergency medical services and hospitals to the Tianjin explosions. Data on injuries, outcomes, and patient flow were obtained from the government and the hospitals.
A total of 46 ambulances and 143 prehospital care professionals were dispatched to the scene, and 198 wounded were transferred to hospitals by ambulance. More than 4000 wounded casualties surged into hospitals, and 798 wounded were admitted. Both emergency medical services and hospitals were quick and successful in the early stage of the explosions. The strategy of 4 centralizations (4Cs) for medical services management in a mass casualty event was successfully applied.
The risk of accidental events has increased in recent years. We should take advantage of the lessons learned from the explosions and apply these in future disasters. (Disaster Med Public Health Preparedness. 2018; 12: 411–414)