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Background: Few studies have investigated the association between cognition and brain volume associated with cerebral small vessel disease (CSVD). Objective: We investigated the association between cognition and brain volume and neuroimaging markers of CSVD in a community-dwelling population. Methods: Participants (n = 993, age≥35 years) from the community-based Shunyi Study were included to investigate the association between neuroimaging markers and cognition cross-sectionally. Magnetic resonance imaging markers included brain volume measurements of the total cerebrum, white matter, gray matter, and CSVD imaging markers. Cognitive performance was assessed using neuropsychological tests of the Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Fuld Object Memory, digit span, Trail Making Test (TMT)-A, and TMT-B. Results: For brain volume measurement, subcortical white matter fraction was positively associated with MMSE score (β= 0.034, p = 0.0062) and MoCA score (β= 0.034, p = 0.0174), and negatively associated with TMT-A and TMT-B completion time (β= –2.319, p = 0.0002; β= –2.827, p = 0.0073, respectively). For evaluation of CSVD imaging markers, the presence of lacunes was positively associated with TMT-B completion time (β= 17.241, p = 0.0028). Conclusion: In community-dwelling populations, reduced white matter volumes, as a consequence of aging and vascular damage, are associated with worse global cognition and executive function. Our findings provide potential insights into the correlation between cognition and CSVD-associated subcortical white matter injury.

Background and Purpose: To compare the risk factors and risk of stroke between lacune and large perivascular spaces (PVSs) in a community-based sample. Methods: Large PVSs were assessed using 3.0T MRI in a population-based cohort consisting of 1,204 participants. The relationship between cardiovascular risk factors, neuroimaging changes, and incidental stroke risk and the presence of lacune or large PVSs was assessed with univariate and multivariable ordinal logistic regression analysis. Results: Of the 1,204 study participants (55.7 ± 9.3 years, 37.0% men), a total of 347 large PVSs were detected in 235 (19.5%) subjects, while a total of 219 lacunes were detected in 183 subjects (15.2%). The presence of lacunes was found to be significantly associated with age, male gender, hypertension, and diabetes, whereas only age (p < 0.01) and ApoEε4 carrier status (p < 0.01) were related to the presence of large PVSs. Those who had lacunes detected on MRI at baseline had a significant increased risk of stroke (hazard ratio [HR] 4.68; 95% confidence interval [CI], 1.15–19.07) during the 3-year follow-up independent of age, gender, and other vascular risk factors. However, there was no significant relationship between the presence of large PVSs and incident stroke (HR 3.84; 95% CI, 0.82–18.04). Conclusions: The lack of association between large PVSs and cardiovascular risk factors or risk of stroke indicated a nonvascular pathogenic mechanism underlying large PVSs, suggesting the importance of distinguishing large PVSs from lacunes in clinical practice.

At present, the diversity of internal parameters of flexible load clusters has become one of the important factors affecting the modeling effectiveness of the unified integrated model of flexible load clusters. Therefore, a unified integrated model considering parameter diversity often produces a natural damping, which makes the system more stable. This paper introduces a modeling method for flexible load aggregation, by means of mathematically modeling a single flexible load, and then establishing a state-transferring model of load power, thereby obtaining the adjustment potential of the load aggregation; Secondly, after the primary aggregation is conducted on the flexible loads, the switch state and power change of the flexible load group are analyzed using the Monte Carlo simulation method, and the relationship between the switch probability distribution and the aggregate power change over time is constructed; Finally, the flexible loads are aggregated again to establish a unified integration model to obtain the operating status and power changes of the entire flexible load group. The simulation is conducted in the setting of a regional integrated energy system including renewable energy, CHP, power/heating storage, and flexible loads to verify the effectiveness of the proposed method.

Grass carp (Ctenopharyngodon idellus) is an important aquaculture species in China that is affected by serious diseases, especially hemorrhagic disease caused by grass carp reovirus (GCRV). Grass carp have previously shown age-dependent susceptibility to GCRV, however, the mechanism by which this occurs remains poorly understood. Therefore, we performed transcriptome and metabolome sequencing on five-month-old (FMO) and three-year-old (TYO) grass carp to identify the potential mechanism. Viral challenge experiments showed that FMO fish were susceptible, whereas TYO fish were resistant to GCRV. RNA-seq showed that the genes involved in immune response, antigen presentation, and phagocytosis were significantly upregulated in TYO fish before the GCRV infection and at the early stage of infection. Metabolome sequencing showed that most metabolites were upregulated in TYO fish and downregulated in FMO fish after virus infection. Intragroup analysis showed that arachidonic acid metabolism was the most significantly upregulated pathway in TYO fish, whereas choline metabolism in cancer and glycerophospholispid metabolism were significantly downregulated in FMO fish after virus infection. Intergroup comparison revealed that metabolites from carbohydrate, amino acid, glycerophospholipid, and nucleotide metabolism were upregulated in TYO fish when compared with FMO fish. Moreover, the significantly differentially expressed metabolites showed antiviral effects both in vivo and in vitro. Based on these results, we concluded that the immune system and host biosynthesis and metabolism, can explain the age-dependent viral susceptibility in grass carp.

Background: Major depressive disorder (MDD) patients face an increased risk of developing cognitive impairments. One of the prominent cognitive impairments in MDD patients is verbal fluency deficit. Nonetheless, it is not clear which vulnerable brain region in MDD is interactively linked to verbal fluency deficit. It is important to gain an improved understanding for verbal fluency deficit in MDD.Methods: Thirty-four MDD patients and 34 normal controls (NCs) completed resting-state fMRI (rs-fMRI) scan and a set of verbal fluency tests (semantic VFT and phonemic VFT). Fourteen brain regions from five brain networks/systems (central executive network, default mode network, salience network, limbic system, cerebellum) based on their vital role in MDD neuropathology were selected as seeds for functional connectivity (FC) analyses with the voxels in the whole brain. Finally, correlations between the z-score of the FCs from clusters showing significant between-group difference and z-score of the VFTs were calculated using Pearson correlation analyses.Results: Increased FCs in MDD patients vs. NCs were identified between the bilateral posterior cingulate cortex (PCC) and the right inferior frontal gyrus (triangular part), in which the increased FC between the right PCC and the right inferior frontal gyrus (triangular part) was positively correlated with the z score of phonemic VFT in the MDD patients. Moreover, decreased FCs were identified between the right hippocampal gyrus and PCC, as well as left cerebellum Crus II and right parahippocampal gyrus in MDD patients vs. NCs.Conclusions: The MDD patients have altered FCs among key brain regions in the default mode network, the central executive network, the limbic system, and the cerebellum. The increased FC between the right PCC and the right inferior frontal gyrus (triangular part) may be useful to better characterize pathophysiology of MDD and functional correlates of the phonemic verbal fluency deficit in MDD.

Objective: To retrospectively investigate the comparative efficacy, safety and cost-benefits of three nutritional treatment schemes including short peptide jejunal nutrition (SPJN), whole protein jejunal nutrition (WPJN), and partial parenteral nutrition (PPN) in patients underwent esophagectomy for esophageal cancer in our hospital. This study was carried out in accordance with the conceptual framework of nutritional therapy in fast-track rehabilitation surgery.Methods: We retrospectively reviewed 305 patients who were assigned to receive esophagectomy for esophageal cancer. Eligible patients was naturally divided into SPJN group [n = 98 (32.1%)], WPJN group [n = 95 (31.1%)], and PPN group [n = 112 (36.7%)] according to the type of nutritional scheme which was actually prescribed to patients by the attendingphysician in clinical practice. The differences of the serum total protein (TP), albumin (ALB), pre-albumin (PA), hemoglobin (HGB), white blood cells (WBCs), red blood cells (RBCs) and neutrophils were compared among 3 nutritional schemes groups. We also investigated the relationship of the fluid intake, urine output, gastric juice drainage volume and thoracic drainage volume among 3 nutritional groups at 3 days after surgery. Moreover, the differences of cost-benefit indexes, complications, length of hospitalization and hospital expenditure were also compared.Results: The serum TP, ALB, and PA in the SPJN group were all higher than those in the WPJN and PPN groups (p < 0.05). The gastric juice volume of gastrointestinal decompression drainage and fluid volume of thoracic drainage in the SPJN group were all less than that in the WPJN group (p < 0.05). The overall hospital stay and post-operative hospital stay in the SPJN group were all shorter than that in WPJN group (p < 0.05). Moreover, the incidence of post-operative complications including anastomotic leakage, infection, and gastrointestinal reaction was remarkably lower in the SPJN group compared to the WPJN group (p < 0.05). Interesting, hospital expenditure in the PPN group was less than that in the SPJN and the WPJN groups (p < 0.001).Conclusion: Patients may obtain benefits in improving protein level after receiving SPJN scheme at the early stage after esophagectomy. Meanwhile, patients may obtain benefits in improving post-operative complications and hospital stay after receiving SPJN or PPN compared to WPJN protocol. However, the difference between SPJN and PPN requires further study because no difference was detected in terms of clinical outcomes including complications and the length of hospitalization although PPN may achieve a possible decrease of medical expenditure.

China has emerged as a leading electric vehicle (EV) market, accounting for approximately half of the global EV sales volume. We employed an atmospheric chemistry model to evaluate the air quality impacts from multiple scenarios by considering various EV penetration levels in China and assessed the avoided premature mortality attributed to fine particulate matter and ozone pollution. We find higher fleet electrification ratios can synergistically deliver greater air quality, climate and health benefits. For example, electrifying 27% of private vehicles and a larger proportion of certain commercial fleets can readily reduce the annual concentrations of fine particulate matter, nitrogen dioxide and summer concentrations of ozone by 2030. This scenario can reduce the number of annual premature deaths nationwide by 17,456 (95% confidence interval: 10,656–22,160), with the Beijing–Tianjin–Hebei, Yangtze River Delta and Pearl River Delta regions accounting for ~37% of the total number. The high concentration of health benefits in populous megacities implies that their municipal governments should promote more supportive local incentives. This study further reveals that fleet electrification in China could have more health benefits than net climate benefits in the next decade, which should be realized by policymakers to develop cost-effective strategies for EV development. Wide adoption of electric vehicles can contribute to mitigate climate change and air pollution. Here the authors develop various fleet electrification scenarios in China to evaluate the associated air quality and health impacts to inform sound policies.

Landslides are one of the most important natural disasters at present. This paper uses machine learning to optimize the design of micro-piles, reinforce the expansive soil landslide, and achieve safety protection. The effective safety protection of the landslide is realized by machine learning design of pile arrangement, pile spacing, row spacing, anchoring depth, sizes and reinforcement bars of piles. It is found that when three-row piles are used to reinforce the expansive soil landslide, the proportional coefficient of the bearing sliding force of each expansive soil is 1:0.7:0.6, in which the distribution of sliding forces is calculated by the respective steel piles. Through the calculation of the overall stability of each pile, the shear bearing capacity and bearing capacity of the sliding surface, the rationality of the design is analyzed and finally verified by the engineering project.

This paper presents an isolated auxiliary power supply for medium-voltage power electronics systems. The proposed converter comprises two stages: a non-isolated ac/dc stage that connects directly to the medium-voltage line, and an isolated dc/dc stage that provides 100-W output power at 24 V, with 10 kV isolation. The proposed modular ac/dc stage uses just one active semiconductor device per module, features an internal capacitor voltage balancing, and achieves power factor correction by employing predictive current control. High switching frequency operation of both converter stages enable a reduction in system size and weight when compared to traditional low-frequency transformer-based approach. The proposed converter is simulated and its operation is validated experimentally on a 100-W prototype.

By subjecting concrete specimens to pressure and tension under different loading conditions, this paper studies the relationships of stress state with crack opening and development and failure forms of specimens. Based on the principle of conservation of energy, it explores the relationship between failure area, failure energy and strength. The numerical calculation and CT test results show that the stress state of concrete determines the failure form, that the failure form determines the failure area, that failure area determines the energy consumed by the failure and that the failure energy determines the strength of the specimen, regardless of how the specimen is loaded.

In theory, discretionary pricing improves the company's performance by allowing managers to incorporate local information into their pricing decisions. However, in practice, managers are vulnerable to behavioral biases that can lead to inaccurate estimation of the customer's willingness to pay and price sensitivity, and precipitate poor decisions. This paper investigates the effectiveness of discretionary pricing and examines how information advantage and behavioral bias influence managers' pricing decisions. Collaborating with a pharmacy retailer, we analyze a quasi-field experiment that delegates pricing power to local pharmacy managers. Our analysis reveals that under discretionary pricing, managers incorporate local information into their pricing decisions. However, they are also subject to behavioral biases, which leads to aggressive, sub-optimal price adjustments. We find that managers increase prices of high-priced drugs by 8.6\%, resulting in significant sales and revenue losses. The effect is particularly prominent in stores located in low-competition areas. Moreover, we find that manager experience can alleviate such behavioral biases---more experienced managers from larger stores are not subject to these biases. Our findings highlight the importance of recognizing managers' behavioral biases in business decisions. We provide implications for pricing practices and offer solutions that allow companies to leverage local information while reducing the impact of human biases.

This paper deals with the multi-physics analysis of surface inset permanent magnet (PM) motors with different slot-pole combinations. Five surface inset PM motors including 24-slot/4-pole (4p24s) integral-slot distributed-winding (ISDW), 27-slot/6-pole (6p27s) fractional slot distributed winding (FSDW), 6-slot/4-pole (4p6s), 9-slot/8-pole (8p9s), 12-slot/l0-pole (10pl2s) fractional slot concentrated winding (FSCW) are designed with the same specifications and analyzed utilizing the finite-element method (FEM). Firstly, the electromagnetic performance is analyzed, including cogging torques, torque characteristics, magnetic and reluctance torque ripples. Then, the electromagnetic vibration and noise are studied through two-dimensional (2D) decomposing of radial force density and modal analysis of stators. Finally, the vibrations under different speeds are discussed. It is concluded that cogging torques of the FSCW motors (8p9s and 10pl2s) are significantly suppressed. The torque characteristic results show that the reluctance torques of distributed winding motors (4p24s and 6p27s) account for a larger proportion of total torques than that of the other three motors. According to the study of magnetic and reluctance torque ripple, the fractional slot motors are better than the integral-slot motors. The vibration and noise analysis results show that the distributed winding motors (4p24s and 6p27s) have lower vibration.

Decentralized methods are recently employed in combined heat and power systems (CHPS), because the electric power systems (EPS) and distribute heating systems (DHS) are controlled independently by different operators. However, most of them only focus on the accuracy of computation results but neglect the cost of communication in computation. In this paper, we develop a communication-censored alternating direction method of multipliers (COCA) to solve the CHPS dispatch problem. Different from the ADMM, the boundary information is allowed to transmit to neighbors in COCA only when its value is significantly changed as compared to its previous value. The censoring function is utilized to measure the difference to improve the efficiency of communication. Experimental results demonstrate that COCA can not only reach the same solution as the centralized method but also reduce communication costs.

Background: Major depressive disorder (MDD) is one of the most common and costly psychiatric disorders. In addition to significant changes in mood, MDD patients face an increased risk of developing cognitive dysfunction. It is important to gain an improved understanding of cognitive impairments and find a biomarker for cognitive impairment diagnosis in MDD. Methods: One hundred MDD patients and 100 normal controls (NCs) completed resting-state fMRI (rs-fMRI) scan, in which 34 MDD patients and 34 NCs had scores in multiple cognitive domains (executive function, verbal fluency, and processing speed). Twenty-seven regions of interest from the default mode network (DMN), central executive network (CEN), salience network (SN), and limbic system (LS) were selected as seeds for functional connectivity (FC) analyses with the voxels in the whole brain. Finally, partial correlations were conducted for cognitive domain scores and FCs with significant differences between the MDD and NC groups. Results: Significant FC differences between groups were identified among the seeds and clusters in the DMN, CEN, LS, visual network, somatomotor network, ventral attention network, and dorsal attention network. In the MDD patients, the magnitude of the Stroop interference effect was positively correlated with the illness duration, and the illness duration was negatively correlated with the FC between the right ventral hippocampal gyrus and the left inferior frontal gyrus. However, the correlation between the Stroop interference effect and the FC of the right anterior prefrontal cortex with the left cerebellum_4_5 was disrupted in these patients. Conclusions: The MDD patients have altered FCs among multiple brain networks and a disrupted correlation between the FC of prefrontal cortex and executive function. The disrupted correlation could present before the symptoms develop and may be the core process in the development of executive function impairment.

This paper studies and introduces the successful case of gob-side entry retaining technology and the typical mining pressure law in Luan mining area, which is the main mining coal seam in Qinshui coalfield. Qinshui coalfield has an estimated coal reserve of 300 billion tons, accounting for 9.58% of the total national coal reserve in China, especially anthracite, chemical coal, and coking coal. The methods of field investigation, theoretical analysis, physical experiment, and industrial test are adopted. Through the field investigation, theoretical analysis, physical experiments, and industrial test, the following conclusions have been drawn in this study: (1) A thorough engineering geological investigation was conducted on the entry retaining along the gob side on noncoal pillar mining working face, which covers multiple periods of mining process including the roadway excavation period, primary mining period, primary mining stability period, and secondary mining influence period. A series of analysis and tests were conducted such as core sampling, rock mechanics property testing, borehole detection, and flexible formwork support evaluation, which laid a foundation for identifying the mining pressure law of gob-side entry retaining by using noncoal pillar mining. (2) The mining pressure law was studied through the collection of the field measurements taken from the entry retaining along the gob side on noncoal pillar mining working face. The keys to achieve the roadway surrounding rock stability through noncoal pillar mining are obtained. According to the study, the stability control of retained roadway surrounding rock mainly depends on the stability of top coal, coal side, and shoulder angle coal. (3) In this study, a roadway reinforcement scheme is proposed to improve the surrounding rock control technology for gob-side entry retaining by noncoal pillar mining, whose effectiveness has been verified by a series of industrial test. Therefore, the wide adoption of the noncoal pillar mining method in Number #3 coal mine can significantly relieve the predicament of coal pressing under a large number of buildings in Luan mining area, which provides insightful guidance to the coal-free pillar mining in the whole Luan mining area.

We usually use a digraph to represent a wireless network (WN). Correspondingly, a connected dominating set (CDS) of the digraph is usually used to denote a virtual backbone (VB) of the corresponding WN. In this article, focusing on the problem of a minimum strongly connected dominating and absorbing set (MSCDAS) with a bounded diameter (or guaranteed routing cost) for a digraph, which is strongly connected, we introduce two algorithms. One is called the guaranteed routing cost strongly connected dominating and absorbing set (GOC-SCDAS), which can generate a strongly connected dominating and absorbing set (SCDAS) with a performance ratio 14.4k+1/22 in respect of the optimal solution. Another is called the α guaranteed routing cost strongly connected bidirectional dominating and absorbing set (α-GOC-SCBDAS), which can generate a strongly connected bidirectional dominating and absorbing set (SCBDAS) with a performance ratio 8.8443k+1/22k+1/22 in respect of the optimal solution and a better routing cost, where k=rmax/rmin and rmin,rmax is the transmission range of nodes in the network. Through the simulation experiments, we obtain the conclusion that in terms of the diameter and average routing path length (ARPL) of CDS, the outputs of our algorithms are better than those of the algorithm in (Du et al. 2006).

In the elderly, brain structural deficits and gait disturbances due to cerebral small vessel disease (CSVD) have been well demonstrated. The relationships among CSVD, brain atrophy, and motor impairment, however, are far from conclusive. Particularly, the effect of CSVD on subcortical nuclear atrophy, motor performance of upper extremities, and associating patterns between brain atrophy and motor impairment remains largely unknown. To address these gaps, this study recruited 770 community‐dwelling subjects (35–82 years of age), including both CSVD and non‐CSVD individuals. For each subject, four motor tests involving upper and lower extremities were completed. High‐resolution structural MRI was applied to extract gray matter (GM) volume, white matter volume, cortical thickness, surface area, and subcortical nuclear (caudate, putamen, pallidum, and thalamus) volumes. The results showed worse motor performance of lower extremities but relatively preserved performance of upper extremities in the CSVD group. Intriguingly, there was a significant association between the worse performance of upper extremities and atrophy of whole‐brain GM and pallidum in the CSVD group but not in the non‐CSVD group. In addition, mediation analysis confirmed a functional CSVD‐to‐“brain atrophy”‐to‐“motor impairment” pathway, that is, a mediating role of thalamic atrophy in the CSVD effect on walking speed in the elderly, indicating that CSVD impairs walking performance through damaging the integrity of the thalamus in aging populations. These findings provide important insight into the functional consequences of CSVD and highlight the importance of evaluating upper extremities functions and exploring their brain mechanisms in CSVD populations during aging.

Electrification has been rapidly promoted to transform the energy source for public transit buses. Among all electric technologies penetrating the public bus fleet, battery electric buses (BEBs) dominates the market. Nevertheless, real-world energy consumption (EC) is of great concern, since BEBs are often used under congested conditions that may affect their energy and environmental benefits. This study proposes an operating mode binning method to assess on-road EC and well-to-wheel (WTW) air pollutants emissions of BEBs under complex real-world usage patterns. Second-by-second EC and operating data of two BEBs demonstrated in Macao, China is adopted to establish the EC profiles under each micro modes. Results show that EC value would be below zero in certain operation modes with negative vehicle specific power values, which suggests the regenerative brake system is effectively functioning under deceleration conditions. Average EC are estimated to be 1.7 to 4.1 kWh km −1 for BEB12 and 1.2 to 2.9 kWh km −1 for BEB10 (i.e., vehicle length of 12 m and 10 m), respectively, under all operating conditions (i.e., 18 various patterns) by average speed, loading mass and air conditioner usage. The large variation in real-world EC would proportionally affect WTW emissions of carbon dioxide (CO 2 ) and air pollutants from BEBs. When deployed in Macao where non-fossil electricity is relatively abundant, BEB can significantly reduce WTW emissions of nitrogen oxides (NO X ) and volatile organic compounds (VOC) by 60%–80%, along with considerable reductions of 10%–40% for CO 2 and fine particulate matters (PM 2.5 ). Further, the benefits related to WTW CO 2 and PM 2.5 emissions would not exist if BEBs are deployed in coal power-rich regions. Our measurement results and WTW emission suggests that current fuel economy testing procedure of BEB should be modified to better inform customers and policy-makers of their real-world performance and benefits.

This paper presents a multiobjective real-time controller for a modular multilevel converter capable of parallel module connectivity, the so-called modular multilevel series parallel converter (MMSPC). The MMSPC topology allows the batteries to be dynamically rewired in various series–parallel configurations, generating a wide range of output voltage levels. The novel control method parallelizes the modules to balance their voltages without the need for individual module voltage monitoring. Additionally, the controller optimizes across the large number of feasible system configurations to minimize switching and conduction losses. Finally, the controller efficiently encodes the system configuration with module interconnection states rather than the module switch states, which substantially simplifies control. Furthermore, this work experimentally validates the MMSPC topology and concept. In the prototype, the parallel mode reduced the system losses at 5 kW output power by 18% and 24% for load power factors of 1.0 and 0.8, respectively. Sensorless balancing via parallelization maintained well-matched module voltages (standard deviation = 0.045 V) over a 5-h battery discharge with highly variable load current. The reduced conduction losses and simple balancing capability of the MMSPC can enable new applications at medium and low voltages that benefit from its high-quality output, elimination of filtering magnetics, fast response, and modularity.

Summary The improvement in the operating range of electric vehicles can be accomplished by robust modelling of the design and optimization of the energy storage capacity of the battery pack system. In this work, the authors have conducted a comprehensive survey on battery modelling methods and identified critical areas of improvement vital for estimating the battery capacity. This work proposes the artificial intelligence approach of automated neural networks search (ANS) in development of the robust battery capacity models for the lithium ion batteries based on the inputs (temperature and discharge rates). The robustness in the models is introduced by incorporating uncertainties in the inputs (the temperature and discharge rates, the architecture of algorithm and the models). The statistical analysis and validation of the models reveal that the models formulated using an ANS approach outperform the response surface regression models with correlation coefficient achieved as high as 0.97. The uncertainty analysis based on normal distribution of the inputs suggests that the models formulated from ANS are least sensitive to change in the input conditions when compared to response surface regression models. The global sensitivity analysis reveals that the temperature is a dominant factor for accurate battery capacity estimation. Copyright © 2017 John Wiley & Sons, Ltd.

This work presents a cost-effective and compact medium-voltage (MV) solid-state transformer (SST). The pro-posed SST is rated at 5kW, and provides a low voltage dc output serving dc loads and sources such as batteries, photovoltaics, and household dc loads. The proposed multi-cell topology features an internal capacitor voltage balancing and requires only one dc-link voltage sensor. A major challenge of the proposed topology is the unbalanced circulating currents when using the conventional interleaved pulse-width modulated (PWM) scheme. The unbalanced circulating currents cause uneven component stress, and may require different current rating among the switch devices. By analyzing non-ideal equivalent circuits of the converter, we propose a new PWM scheme that minimizes and balances the circulating currents, thus increasing system efficiency. The proposed modulation scheme is verified on a full scale prototype.

Background Few studies have investigated the correlation between cerebral microbleeds (CMBs), a hemorrhagic imaging marker of cerebral small vessel disease (CSVD), and brain volume. Objective We investigated the association between the burden and locations of CMBs and brain volume in community-dwelling populations. Methods Data were obtained from 1,029 participants who underwent brain magnetic resonance imaging (MRI) and APOE genotyping. Volumes of the whole brain, subcortical white matter (WM), cortical gray matter (GM), and hippocampus were extracted. Linear regression models were used to investigate the relationship between the CMB burden and their location with structural changes. Results Regarding burden, participants with≥3 CMBs had significantly lower whole brain (β= -1.124, p = 0.0133), subcortical WM (β= -1.020, p = 0.0043), and hippocampus (β= -0.015, p = 0.0088) volumes than those without CMBs. Regarding location and burden, the presence of≥3 strictly lobar CMBs was negatively associated with whole brain volume (β= -2.838, p = 0.0088). Additionally, higher CMB burdens in strictly lobar locations or deep/mixed locations were associated with lower subcortical WM volume (β= -1.689, p = 0.0482; β= -0.872, p = 0.0464, respectively). Finally, the presence of≥3 deep/mixed CMBs was associated with lower hippocampus volume (β= -0.018, p = 0.0088), and these associations were independent of other ischemic markers of CSVD. However, the CMB burden and distributional pattern did not correlate with cortical GM volumes. Conclusion A higher CMB burden, in specific locations, is associated with decreased brain volumes in community-dwelling populations.

A method to design and optimize a Medium Frequency Transformer (MFT) based on commercially available components and semiconductor and converter constraints is presented. The optimization algorithm is used to redesign the transformer for a scaled-down electric vehicle (EV) fast charger using a three-level resonant circuit topology. The main consideration of this paper is the uncertainty caused by modeling assumptions in optimization algorithms. To reduce this uncertainty, space mapping is used to create an optimized design point. Finally, a comparison of the designs found using the original optimization algorithm and the space mapping technique are compared and analyzed. For simplicity, only a single objective optimization routine is employed.

This paper presents a medium-voltage (MV) (12.47 kV), 350 kW electric vehicle (EV) fast charger using 10 kV SiC MOSFETs. Detailed system design procedure based on the 10 kV SiC MOSFET characterization is presented to provide a guide on the 10 kV SiC MOSFET converter development. Taking the advantage of the 10 kV SiC MOSFET’s high voltage blocking capability and efficient switching performance, a single module high power density system is designed with the DC/DC stage operates at 25 kHz and the simulated system efficiency exceeds 98%, input current THD lower than 2%. With all the passive components selected, the designed system power density is 1.6 kW/L.

Bus and metro are the two most important public transport modes in many metropolises in China, and they both have experienced rapid growth and meanwhile coexisted for decades. However, little is known on how the metro and bus interacted with each other during their rapid growths. This study was proposed to investigate the growth and interaction of bus-metro from the macro perspective. The passenger volume data for metro and bus were collected from seven central cities to represent the development of the two public transport modes, and the Logistic model and Lotka–Volterra model were employed to model the growth as well as the interaction of bus-metro, respectively. The modeling results show that the development of bus conforms to the Logistic model (i.e. S-shaped curve), while the bus-metro interaction conforms to the Lotka–Volterra model with interaction modes of competition (Shanghai city from 2000–2009, Shanghai city from 2009–2018, Guangzhou city from 2009–2017, Nanjing city from 2008–2018), and mutualism (Guangzhou city from 2000–2009). The further analysis indicates that urban characteristics and policies determine the interaction, and the parameters of the Lotka–Volterra model could be used to judge the bus-metro interaction type.

The present study was designed to evaluate the potential role of miR-93 in cerebral ischemic/reperfusion (I/R) injury in mice. The stroke model was produced in C57BL/6 J mice via middle cerebral artery occlusion (MCAO) for 1 h followed by reperfusion. And miR-93 antagomir was transfected to down-regulate the miR-93 level. Our results showed that miR-93 levels in the cerebral cortex of mice increased at 24 and 48 h after reperfusion. Importantly, in vivo study demonstrated that treatment with miR-93 antagomir reduced cerebral infarction volume, neural apoptosis and restored the neurological scores. In vitro study demonstrated that miR-93 antagomir attenuated hydrogen peroxide (H2O2)-induced injury. Moreover, miR-93 antagomir suppressed oxidative stress in I/R brain and H2O2 treated cortical neurons. Furthermore, we founded that down-regulation of miR-93 increased the expression of nuclear factor erythroid 2-related factor (Nrf2) and heme oxygenase-1 (HO-1) and the luciferase reporter assay confirmed that miR-93 directly binds to the predicted 3'-UTR target sites of the nrf2 gene. Finally, we found that knockdown of Nrf2 or HO-1 abolished miR-93 antagomir-induced neuroprotection against oxidative stress in H2O2 treated neuronal cultures. These results suggested that miR-93 antagomir alleviates ischemic injury through the Nrf2/HO-1 antioxidant pathway.

Postpartum weight retention is a significant contributor to obesity in reproductive-aged women, but the key implementation characteristics of postpartum weight management interventions have not been systematically identified to inform policy and practice. This study aimed to evaluate the intervention characteristics associated with weight loss in postpartum women using the Template for Intervention Description and Replication (TIDieR) framework. We searched MEDLINE, CINAHL, EMBASE, PSYCINFO, and EBM databases to identify lifestyle intervention RCTs in postpartum women (within 2 years after birth) published up to January 2018. From 4512 studies, 33 studies were included in the systematic review and meta-analysis (n = 4960 women). Health professional-delivered interventions had significantly greater weight loss than those delivered by nonhealth professionals (mean difference, 95% confidence interval: (-3.22 kg [-4.83, -1.61] vs -0.99 kg [-1.53, -0.45], P = 0.01 for subgroup differences)). Diet and physical activity combined had significantly greater weight loss compared with physical activity-only interventions (-3.15 kg [-4.34, -1.96] vs -0.78 kg [-1.73, 0.16], P = 0.009 for subgroup differences). The extent of weight loss was not influenced by intervention intensity (duration, number of sessions) and setting (individual or group).

Objective This study was designed to verify the association between dementia and mortality in the elderly undergoing hip fracture surgery, and assessed the mortality of patients with dementia after hip fracture surgery. Material and methods PubMed, Embase, and Web of Science were searched until April, 2018 without language restrictions. Two reviewers selected related studies, assessed study quality, and extracted data independently. Risk ratios (RRs) with 95% confidence intervals (CI) were derived using random-effects model throughout all analyses. The endpoints included 30-day, 6-month, 1-year, and more than 1-year mortality. This meta-analysis was performed following PRISMA statement and carried out by using stata14.0 software. Results Dementia significantly increased postoperative mortality of patients suffered from hip fracture in 30-day [RR = 1.57, 95% CI (1.29, 1.90), P

As spectrum scarcity and inter cell interference (ICI) are both limiting factors in wireless cellular system, ICI coordination (ICIC) techniques play an important role in improving system performance. Soft Frequency Reuse (SFR) is an effective way to manage the spectrum and reduce ICI in cellular system. It carries out resource allocation prior to system deployment, and dynamic schemes allocate resource regardless of the actual network traffic and interference distribution, both of which limit the potential system performance. Energy Internet’s deployment is becoming more and more intensive. It is important to increase system throughput and reduce data error rate. In this paper, an adaptive resource allocation scheme (ARAS) is proposed which first dynamically optimizes resource allocation according to interference distribution and traffic load. In ARAS, the interference thresholds and the roles of victim and aggressor require to be specific. For each victim user, their dominant interferer (DI) applies the Different Evolution (DE) to find the optimal transmission power reduction, aiming at improving victim users’ performance and guaranteeing data requirement. To improve system performance, extra resources are allocated to balance ICIC and system capacity. Simulation results show that the ARAS achieves better SINR and throughput compared with existing ICIC schemes.

This paper presents an auxiliary power supply for medium-voltage (MV) power electronics systems, based on modular multilevel series-parallel converter (MMSPC). The converter connects to 2.4 kV RMS at the input, and produces 24 V dc at the output, providing 100 W of power with 10 kV isolation. Unlike the traditional solutions which use a grid-frequency bulky and heavy potential transformers, the proposed converter can operate at higher switching frequencies, thus reducing the weight and providing higher power density, compared to the traditional approach. Additionally, the proposed converter features an internal capacitor voltage balancing and achieves power factor correction (PFC) by using predictive control. The proposed converter is simulated and its operation is experimentally validated on the developed prototype at low input voltage.

In the paper, a novel pulse ignition circuit is proposed for electronic ballast with the zero-voltage-switching quasi-square wave (ZVS-QSW) converter; the voltage pulse of the proposed igniting circuit contains both a high frequency part and a low frequency part; the high frequency part made it easy to exit the gas in the ionization conduction state in the high-intensity discharge lamp, and the low frequency part makes it easy to lower the igniting potential and provides the continuous pulse energy. The circuit is with few components, low costs, high reliability, and easy to control. The circuit model is analyzed in detail and the influence of the circuit parameters on the pulse amplitude and width is given in this paper. The peak current is limited and the amplitude variation caused by the deviation of the parasitic capacitor for the transformer is restricted by the auxiliary inductor. The auxiliary inductor and the transformer parasitic capacitor form another resonant circuit. As a result, an igniting pulse sequence with two different frequencies is applied to the lamp and both pulse amplitude and width are guaranteed. In the laboratory, the circuit is used in a 70-W metal halide lamp electronic ballast with the ZVS-QSW converter, and the lamp can be ignited reliably.

A two-stage street lighting system is presented, where the front stage is a single-stage AC/DC converter based on the sepic circuit and flyback converter. Since the sepic circuit and flyback converter share a switching device, the costs of the system can be reduced, and the efficiency and reliability can be improved. At the same time, the switch operates in quasi-resonant state, which reduces the switching losses and enhances the efficiency. The second stage is a light-emitting diode constant current circuit, which achieves the constant current control by adopting boost circuit in peak current control mode. A 100 W prototype is presented, which confirms the correctness of the analysis, the front stage work in the soft-switching condition and the efficiency is up to 83% when the system is in full load condition.

// Yang Yu 1,* , Xinyu Liang 3,* , Haikuo Yu 5 , Weina Zhao 1 , Yan Lu 6 , Yue Huang 7 , Changhao Yin 1 , Gaolang Gong 3 , and Ying Han 2,4 1 Department of Neurology, Hongqi Hospital of Mudanjiang Medical University, Mudanjiang, Heilongjiang, China 2 Department of Neurology, XuanWu Hospital of Capital Medical University, Beijing, China 3 State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China 4 Center of Alzheimer’s Disease, Beijing Institute for Brain Disorders, China 5 Department of Rehabilitation, XuanWu Hospital of Capital Medical University, Beijing, China 6 Department of Ophthalmology, Xuan Wu Hospital, Capital Medical University, Beijing, China 7 School of Medical Sciences, Faculty of Medicine, UNSW Australia, Sydney, Australia * These authors have contributed equally to this work Correspondence to: Ying Han, email: // Gaolang Gong, email: // Changhao Yin, email: // Keywords : mild cognitive impairment, neuroimage, Gerotarget Received : September 02, 2016 Accepted : December 07, 2016 Published : December 15, 2016 Abstract Changes in white matter (WM) microstructure may relate to the pathophysiology of cognitive impairment. Whether WM microstructure differs in two common pre-dementia subtypes, vascular mild cognitive impairment (VaMCI) and amnestic mild cognitive impairment (aMCI), is largely unknown. This study included 28 VaMCI (12 men, age: 46 ~ 77 years) and 34 aMCI patients (14 men, age: 51 ~ 79 years). All patients underwent a battery of neuropsychological tests and structural and diffusion magnetic resonance imaging (MRI) scanning. WM microstructure was quantified using diffusion MRI parameters: fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AxD) and radial diffusivity (RD). These parameters were compared between the two patient groups using tract-based spatial statistics (TBSS) after controlling for age, gender, and education. No significant differences in FA/MD/AxD/RD were observed between the VaMCI and aMCI groups, which suggests a similar pattern of WM microstructure in the early stage of cognitive impairment for different dementia types. However, the two groups exhibited significant differences in the relationship between FA and the Auditory Verbal Learning Test (AVLT), which were primarily located around the corona radiate and corpus callosum. Specifically, there were significant positive correlations (R = 0.64, P < 0.001) between the FA and AVLT in the VaMCI group, but the opposite trend was observed in the aMCI group (R = -0.34, P = 0.047). The differential relationship between WM and memory between VaMCI and aMCI indicates an independent neuropathology for specific memory deficits in different types of dementia.

This paper presents an isolated medium-voltage, high-power-quality and high efficiency (over 96%), fast charger for plug-in electric vehicles. The proposed fully modular fast charger uses off-the-shelf Silicon Carbide (SiC) power devices to convert the rectified single-phase 2.4 kV medium-voltage input to variable dc output. The adopted input-series-output-parallel unidirectional topology enables converter scalability in both the input voltage and the output power. Using wide bandgap (WBG) power devices enables 9 times reduction in volume and 6 times reduction in weight, compared to the state-of-the-art fast chargers, while exceeding the efficiency of the state-of-the-art fast chargers by more than 1.5% Based on the system requirements, the appropriate converter topology was selected, its operation was simulated and validated by experiments on the developed fast charger prototype.

This paper presents an isolated power converter module for medium-voltage (2.4 kV), high-power-quality (PF ≥ 0.98, current THD ≤ 2%), 50 kW fast charger for plug-in electric vehicles. The proposed high-efficiency (above 96%), and reduced-footprint converter module utilizes off-the-shelf Silicon Carbide (SiC) devices to step down the rectified single-phase medium-voltage input. The developed module can also serve as a building block for other medium voltage rectifier applications, including power supplies for data centers and other dc power distribution systems. Based on the system requirements, the appropriate unidirectional converter topology was selected, its operation was simulated and validated by experiments on the developed converter prototype.

We present a control approach for the modular multilevel converter (MMC) with series and parallel module connectivity (MMSPC) that provides natural module balancing, reduced conduction losses, and enhanced robustness afforded by the parallel mode. In conventional MMC control, the voltage of each module's storage element has to be measured or estimated to enable the controller to equalize the voltages across all modules. This requirement has been one of the key barriers for MMCs in low and medium power applications. In contrast, we use the parallel connectivity of the MMSPC for module voltage balancing. It also enables robust operation in the presence of battery failure by supporting the module voltage with frequent parallelizations of the residual module capacitance. The parallel connectivity further reduces conduction losses at voltage levels below the system maximum by decreasing the effective source impedance. This approach renders attractive for the first time low and medium power MMC applications as well as MMC-based battery storage. These are illustrated with an experimental MMSPC system comprising eight battery modules that generates high-quality ac output without filtering magnetics.

According to the modern bridge health assessment and testing methods, compared with the traditional manual test to determine fracture, detection method based on digital image which applies digital image processing and pattern recognition technology to test and assess the bridge surface defect images has the characteristics of non-contact and high precision. Taking the grey-scale feature of the crack, this paper will put forward a kind of crack detection method based on multi-scale and multi-perspective. In view of the interference factors such as the holes, dirties and the others on the concrete pavement, we should analyze the characteristics of collected road surface images, and adopt DWT and NSST to resolve the source images from multiscale, and then establish grey value similarity function, and withdraw the suspected crack information according to the similarity of contrast; second, remove the false crack use connected component measurement, and transfer the problem into graph theory problem; last, use the approximation coefficient of NSST domain, the fusion approximate coefficient of DWT domain and fusion detail coefficients to inverse, transform and rebuild fusion images so as to extract real crack. Through a lot of tests on the concrete pavement picture, experimental results show that this method can achieve real pavement cracks feature extraction, and enjoys a strong practicability.

Background Australian guidelines for cervical cancer screening are being revised under the “renewal program”. Physicians’ willingness to accept these changes will play a pivotal role in its success. Objective To understand the willingness and acceptance of, as well as barriers and facilitators for Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG) affiliates to screening using human papillomavirus (HPV) testing, starting at 25 years of age, every 5 years. Study design An electronic survey of RANZCOG affiliates was undertaken April–June 2014, while renew was announced April 28th 2014. Responses used a 7 point Likert scale, which was dichotomized as ≤4, indicating ‘unwilling’ and >4, indicating ‘willing’ to adopt revised practices. Results Response rate was 22% ( n = 956): 60% were obstetricians and gynaecologists (OG); 27% general practitioner diplomates; 13% OG trainees. Overall, 60% ( n = 526/874) were willing to revise their screening practice. This correlated with awareness of new guidelines ( p = n = 438/869) of respondents were concerned about delaying to 25 years, and 48% ( n = 421/869) concerned cervical cancers would be missed. Reasons respondents gave for wishing to continue screening from 18 years contrary to guidelines included: women not being vaccinated (65.6%), immunosuppressed women (92.2%) and women who had been victims of childhood sexual assault (73.9%). Conclusions The majority of RANZCOG affiliates were willing to change screening practice however, a number of barriers to delaying onset of screening age to age 25 years were reported. Effective change management strategies will need to be implemented to address the concerns raised to ensure best practice for cervical screening.

In order to design and optimize the trolly frame of stacker-reclaimer running mechanism, it is very convenient and efficient to take advantage of ANSYS, which can not only ensure security but also reduce time and cost. The stacker-reclaimer is a common continuous and efficient bulk materials stevedoring and transporting device in the world, running mechanism is located in bottom of the whole machine, which plays an important role of supporting the machine and the running function of the machine. Therefore, the security and reliability of the running mechanism is very significant and critical in the safe operation of the whole machine. To guarantee stiffness and hardness of the steel structure, it is carried out that the static analysis of the key components the trolly frame by using finite element analysis software. Through careful analysis and research, it proves that the design of the components meets completely requirements of real conditions.