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A liquid metal Filtering Power Divider (FPD) with frequency tuning and controllable number of passbands is proposed in this paper. According to the resonance characteristics of uniform impedance resonator (UIR) and stub loaded resonator (SLR), the structure parameters of the FPD are given. The proposed FPD consists of 4 UIRs, 4 SLRs and the liquid metal adjustable modules. By changing the position and length of liquid metal, different center frequency and passband number can be obtained. Two-passband and three-passband are realized on the same FPD. In the two-passband mode, the center frequency of both passbands can be tuned. In the three-passband mode, there are two tuning modes, which can tune the first two pass bands and the third pass band respectively. The designed FPD innovatively applies liquid metal to the structure and has flexible adjustability. In order to verify the proposed design, a reconfigurable FPD based on liquid metal is fabricated and measured. The measured results are in good agreement with the simulated results.

A circular polarization (CP)-agile and continuous beam-steerable array antenna is presented using a hybrid design approach. It is accomplished by combining digital reconfigurable antenna elements with analog continuously tunable phase shifters. To realize both polarization reconfiguration and initial phase generation for beam-scanning simultaneously, the designed antenna element enables eight states that corresponds to two CP modes with four quantized phases. The phase shifters further provide additional variable phases of -90° to 0° for antenna element excitation. Superposition of the initial and additional phases helps to satisfy a full and continuous 360° phase coverage for a beam-steerable array. Meanwhile, the phase decomposition also facilitates the design of phase shifters without complex or cascaded structures. By altering the bias states of the electronic components loaded in the array antenna, CP switching and beam scanning can be independently controlled. For verification, prototypes of the antenna element, phase shifter, and a four-element array are all fabricated and tested. Reasonable agreement is obtained between simulation and measurement. The resultant array could scan up to nearly ±40° off the boresight, along with stable radiation patterns and good CP performance.

Background Patients with chronic obstructive pulmonary disease (COPD) can have recurrent exacerbations and acute respiratory failure (ARF) triggered by particulate matter with a diameter of ≤2.5 μm (PM2.5). To prevent ventilator shortages, this study investigated the short-term association between PM2.5 concentration and emergency department visits (EDVs) among patients with acute exacerbation of COPD (AECOPD) requiring mechanical ventilation (MV). Methods We conducted a time-series study to predict the PM2.5 concentration and number of ventilators needed. Daily counts of EDVs among AECOPD patients requiring ventilation from 2015 to 2019 were obtained from a hospital. Generalized linear models extending Poisson regression were used to explore the association of AECOPD with PM2.5 after controlling for the time trend, seasonal variations, and meteorological variables. Results Eight hundred seventy-five AECOPD patients receiving MV were recorded, of whom 734 received noninvasive ventilation and 141 received invasive ventilatory support. EDVs for AECOPD patients with ARF significantly increased by 3.5% (95% confidence interval [CI]: 2.51%–4.42%) per 10 μg m−3 increase in PM2.5 concentration. Among seasons, PM2.5 concentration had the strongest effect on AECOPD patients with ARF in spring ( Conclusion This is the first study to predict the number of ventilators required by calculating quantitative estimates of the short-term effects of PM2.5 on EDVs for AECOPD patients with ARF. Adverse effects of PM2.5 on AECOPD patients requiring MV are evident, especially in the spring. Establishing protective standards and reducing the PM2.5 concentration to below various thresholds are urgently needed.

Background Research into the potential utility of plasma-derived circulating cell-free nucleic acids as non-invasive adjuncts to radiological imaging have been occasioned by the invasive nature of brain tumour biopsy. The objective of this study was to determine whether significant differences exist in the plasma transcriptomic profile of glioma patients relative to differences in their tumour characteristics, and also whether any observed differences were representative of synchronously obtained glioma samples and TCGA glioma-derived RNA. Methods Blood samples were collected from twenty glioma patients prior to tumour resection. Plasma ccfmRNAs and glioma-derived RNA were extracted and profiled. Results BCL2L1, GZMB, HLA-A, IRF1, MYD88, TLR2, and TP53 genes were significantly over-expressed in glioma patients (p p p = 0.022, versus low-grade glioma patients). There was positive correlation between the magnitude of fold change of differentially expressed genes in plasma- and glioma-derived RNA (Spearman r = 0.6344, n = 14, p = 0.017), and with the mean FPKM in TCGA glioma-derived RNA samples (Spearman r = 0.4614, n = 19, p r = 0.9813, n = 20, p Conclusion We identified significant differential expression of genes involved in cancer inflammation and immunity crosstalk among patients with different glioma grades, and there was positive correlation between their transcriptomic profile in plasma and tumour samples, and with TCGA glioma-derived RNA.

This letter proposes a converter-level method for measuring the on -state voltages of all power semiconductors in a single-phase inverter by using a single circuit only. The proposed circuit distinguishes itself by connecting to the middle point of each phase leg, instead of the two power terminals of individual devices as conventional methods do. It has the advantages of reduced circuit complexity, size, cost, and ease of connection. The principle and theoretical analysis of the proposed converter-level method are discussed. A case study on a single-phase full-bridge inverter is demonstrated to prove the concept.

A significantly negative reversion in the QuantiFERON-TB Gold In-tube (QFT-GIT) test is reported in patients on dialysis, which makes the results unreliable. The CD4 and CD8 responses of the QFT-Gold plus (QFT-Plus) may have better positive consistency, but this needs to be investigated. We enrolled dialysis patients with baseline positive QFT-GIT0 results and conducted two rounds of follow-up paired QFT-GIT1&2 and QFT-Plus1&2 tests at an interval of 6 months. The positive consistency, concordance, and discordance of the QFT results were analyzed. A total of 236 patients on dialysis were screened, and 73 participants with positive QFT-GIT0 results were enrolled. The baseline QFT-GIT0 response was higher in the 1st QFT-Plus1(+) group than in the QFT-Plus1(−) group, but insignificantly different between the 1st QFT-GIT1(+) and QFT-GIT1(−) groups. The two assays had good correlation when concurrently tested. Fifty-three subjects completed a second round of the QFT-GIT2 and QFT-Plus2. Persistent positivity was higher with the QFT-Plus2 (81.8%) than with the QFT-GIT2 (58.8%, p = 0.040). The QFT-GIT1 and QFT-Plus1 CD4 responses were higher in patients with persistent positivity than in those with negative reversion, whereas the difference of the QFT-Plus TB1 and TB2 data, representative of the CD8 response, were similar between positive persistence and negative reversion. In conclusion, the QFT-Plus provides more reliable positive consistency than does the QFT-GIT. The CD4 interferon-γ response might play a role in maintaining positivity of LTBI.

This letter proposes a testing method to emulate realistic stress conditions of DC and AC capacitors, with minimum required power supply and robust operation at the presence of capacitor degradation. It is especially suitable for parameter characterization and accelerated degradation testing of high-voltage and high-ripple current power electronic capacitors. The circuit architecture of the proposed testing method and the constraints of the testing samples under given designs are discussed. Proof-of-concept experiments on both DC and AC capacitors verify the feasibility.

This article proposes a mission profile-based reliability prediction method for modular multilevel converters (MMCs). It includes key modeling steps, such as long-term mission profile, analytical power loss models, system-level and component-level thermal modeling, lifetime modeling, Monte Carlo analysis, and redundancy analysis. Thermal couplings and uneven thermal stresses among submodules are considered. A case study of a 15-kVA down-scale MMC has been used to demonstrate the proposed method and validate the theoretical analysis. The outcomes serve as a first step for developing realistic reliability analysis and model-based design methods for full-scale MMCs in practical applications.

The active capacitor concept based on power electronic circuits has been proposed recently to exceed the physical limit of the passive capacitor. It retains the physical convenience of use as a passive capacitor and has the potential to increase either the power density or the lifetime depending on the applications. However, the cost of the existing design by using ceramic or film capacitors to achieve extreme performance increases a lot, which must be taken into account in the design from the industry aspect. This article proposes a cost-constrained design of an active capacitor used for dc-link applications. It is implemented based on high-current electrolytic capacitors instead of film capacitors or ceramic capacitors. A model-based optimization design procedure is discussed in terms of performance factors of interest. A case study of a 5.5-kW single-phase inverter demonstrates a 38% volume reduction of the dc link with the proposed active capacitor under specific constraints of cost, volume, power loss, and lifetime. The outcomes move one step further for the practical application of the active capacitor concept.

This letter proposes a novel capacitor condition monitoring method for modular multilevel converters (MMCs) based on reference submodules (SMs). It significantly enhances the capacitor monitoring accuracy by making full use of the SM voltage sensor measurement range. Accuracy comparison between the existing method and the proposed method is conducted to quantify the improvement of accuracy. Moreover, its operation principle and practical implementation considerations are presented. Finally, a three-phase MMC platform is built to experimentally verify the effectiveness of the proposed method.

The COVID-19 outbreak can be seen as a 'big test' for China; a summative assessment of its preparedness on multiple fronts, including medical education. Being intimately involved in the coordinated response, the First Affiliated Hospital of Sun Yat-sen University has been a first-hand witness to the strengths and weaknesses of the current medical education system in China. On the one hand, we believe that the distinguished contributions in disease containment efforts by healthcare professionals indicated that our medical education system has achieved its intended outcomes and is socially accountable. On the other hand, we have also identified three major issues that need to be addressed from an educational standpoint: insufficient emphasis on public health emergency preparedness; unsophisticated mechanisms for interdisciplinary cooperation; and inadequate guidance in medical ethics. Whilst these reflections might be seen in its summative form, we would suggest changing it to that of a formative process, where we learn from our assessment through observation and feedback of the gaps, upon which improvement of our present situation can be made. We hope that these lessons may be helpful to our colleagues in the rest of China and around the world, who are engaged in medical educational reform.

Background The risk of tuberculosis (TB) in patients with impaired kidney function remains unclear by different stages of renal function impairment. Methods We retrospectively recruited all patients with kidney function in a tertiary-care referral center from January 2008 to December 2013 and followed them till December 2016. We defined the primary outcome as active TB development and analyzed the impact of kidney function impairment. Results During the study period, a total of 289,579 patients were enrolled for analysis, and of them, 1012 patients had active TB events in an average of 4.13 years of follow-up. According to kidney function impairment, the incidence rate of TB was similar in patients with no chronic kidney disease (CKD) or stage 1 and stage 2, and it increased apparently at stage 3a (167.68 per 100,000 person-years) to stage 3b, stage 4 and stage 5 (229.25, 304.95 and 349.29 per 100,000 person-years, respectively). In a Cox proportional hazard regression model, the dose response of TB risk among different stages of kidney function impairment increased significantly from CKD stage 3a to stage 5. Patients with long-term dialysis had a hazard ratio of 2.041 (1.092–3.815, p = 0.0254), which is similar to that of stage 4 CKD but lower than that of stage 5. Conclusion In patients with impaired kidney function, the risk of TB increases from CKD stage 3, and in stage 5, the risk is even higher than that of those receiving dialysis. Further strategies of TB control need to consider this high-risk group.

With the increasing penetration of renewable power, its reliability and cost-effective production are becoming more important. A filter is inserted between the grid-connected inverter and the power grid to reduce the PWM switching harmonics, which may become a fragile part seen from the power electronics converter perspective. As the grid-connected inverter is typically designed with additional reactive power capability, this paper tries to investigate the additional stresses of the filter capacitor introduced by the reactive power injection. According to an electro-thermal stress evaluation, the time-to-failure distribution of a single LCL filter capacitor is investigated in detail. Moreover, the increasing equivalent series resistance along with the operational period is taken into account. Aiming towards a system-level reliability analysis, a Weibull distribution based reliability of an individual capacitor can be linked to the reliability of a capacitor bank by using a reliability block diagram. A case study of a 2 MW wind power converter shows that the lifetime is significantly reduced from the individual capacitor to the capacitor bank. Besides, over-excited reactive power injection further reduces the lifetime of the LCL filter capacitors.

Various methods have been presented in the past to emulate the electrical behavior of modular multilevel converters (MMCs). To meet the demands for the reliability aspect study of MMCs, this paper proposes a viable setup to emulate the thermal behavior and to investigate its feasibility for reliability testing and thermal model validation of the power modules in the MMC. The proposed mission profile emulator has three distinctive features: 1) capable of emulating and measuring the thermal stresses of power modules; 2) capable of implementing practical switching profile as a full-scale MMC; and 3) having significantly reduced requirement for dc power supply compared to existing setups used for electrical studies. Theoretical discussions, and simulations as well as the experimental results are presented to demonstrate the capability of the mission profile emulator both electrically and thermally. Moreover, this paper is accompanied by a video demonstrating how to measure the junction temperature of the power devices using the optical fiber and the thermal camera.

Improvement in the efficiency of distributed generation (DG) inverters is a concern and challenge for researchers across the globe. To address the concern, an inverter control technique is developed. Inverters have issues with voltage regulation and harmonics when operating in the grid-connected (GC) and stand-alone (SA) mode. This article proposes a control strategy capable of operating DGs in both SA and GC environments. The GC operation of the inverter is achieved by the current control mode, and the SA control features a voltage control loop capable of overcoming the drawbacks due to load shedding or load switching. Besides, the harmonics due to various conditions of transition and load switching are eliminated by adapting a harmonic elimination pulsewidth modulation (PWM) scheme. To enhance the performance of the inverter and eliminate the problem of flexibility associated with conventional and offline switching angle calculations in the PWM technique, a bioinspired intelligent algorithm is adapted. The developed system is verified for various reduced total harmonic distortions (THDs) by performing simulations and experiments. The results depict that the output voltage is regulated for varying load conditions, and the THD is observed to be 2.4% under varying load conditions.

Background: Neuropathic pain (NP), a severe and disruptive symptom following many diseases, normally restricts patients' physical functions and leads to anxiety and depression. As an economical and effective therapy, exercise may be helpful in NP management. However, few guidelines and reviews focused on exercise therapy for NP associated with specific diseases. The study aimed to summarize the effectiveness and efficacy of exercise for various diseases with NP supported by evidence, describe expert recommendations for NP from different causes, and inform policymakers of the guidelines.Design: A systematic review and expert consensus.Methods: A systematic search was conducted in PubMed. We included systematic review and meta-analysis, randomized controlled trials (RCTs), which assessed patients with NP. Studies involved exercise intervention and outcome included pain intensity at least. Physiotherapy Evidence Database and the Assessment of Multiple Systematic reviews tool were used to grade the quality assessment of the included RCTs and systematic reviews, respectively. The final grades of recommendation were based on strength of evidence and a consensus discussion of results of Delphi rounds by the Delphi consensus panel including 21 experts from the Chinese Association of Rehabilitation Medicine.Results: Eight systematic reviews and 21 RCTs fulfilled all of the inclusion criteria and were included, which were used to create the 10 evidence-based consensus statements. The 10 expert recommendations regarding exercise for NP symptoms were relevant to the following 10 different diseases: spinal cord injury, stroke, multiple sclerosis, Parkinson's disease, cervical radiculopathy, sciatica, diabetic neuropathy, chemotherapy-induced peripheral neuropathy, HIV/AIDS, and surgery, respectively. The exercise recommended in the expert consensus involved but was not limited to muscle stretching, strengthening/resistance exercise, aerobic exercise, motor control/stabilization training and mind-body exercise (Tai Chi and yoga).Conclusions: Based on the available evidence, exercise is helpful to alleviate NP intensity. Therefore, these expert consensuses recommend that proper exercise programs can be considered as an effective alternative treatment or complementary therapy for most patients with NP. The expert consensus provided medical staff and policymakers with applicable recommendations for the formulation of exercise prescription for NP. This consensus statement will require regular updates after five–ten years.

BackgroundThe incidence of nontuberculous mycobacterial lung disease (NTM-LD) is increasing worldwide. Immune exhaustion has been reported in NTM-LD, but T-cell immunoglobulin and mucin domain-containing protein 3 (TIM3), a co-inhibitory receptor on T cells, has been scarcely studied.MethodsPatients with NTM-LD and healthy controls were prospectively recruited from July 2014 to August 2019 at three tertiary referral centers in Taiwan. We examined TIM3 expression on the T cells from the participants using flow cytometry. TIM3 expression was analyzed for different disease statuses and after treatment. The apoptosis and cytokine profiles were analyzed according to the TIM3 expression.ResultsAmong enrolled subjects (47 patients and 46 controls), TIM3 on CD4+ cells (6.44% vs. 4.12%, p = 0.028) and CD8+ cells (18.47% vs. 9.13%, p = 0.003) were higher in NTM-LD patients than in the controls. The TIM3 level on CD4+ and CD8+ T cells was positively associated with T-cell apoptosis in the NTM-LD patients. In stimulating peripheral blood mononuclear cells using PMA plus ionomycin, a high TIM3 level on T cells correlated with low interleukin-2 and tumor necrosis factor-alpha (TNF-α) on CD4+ cells and interferon-gamma and TNF-α on CD8+ T cells. For clinical manifestation, low body mass index (BMI), positive sputum acid-fast smear, and high radiographic score correlated with high TIM3 expression on T cells. After NTM treatment, TIM3+ decreased significantly on CD4+ and CD8+ T cells.ConclusionsIn patients with NTM-LD, TIM3+ expression increased over CD4+ and CD8+ T cells and correlated with cell apoptosis and specific cytokine attenuation. Clinically, TIM3+ T cells increased in patients with low BMI, high disease extent, and high bacilli burden but decreased after treatment.

Key Points Question Are underlying inflammatory pathways and body composition profiles associated with less favorable 5-year colon cancer outcomes? Findings In this cohort study including 28 patients with nonmetastatic colon cancer, high visceral fat and low muscle mass were associated with increased inflammatory activity and poor 5-year cancer outcomes, including recurrence and disease-specific mortality. Low skeletal muscle area and high visceral to total fat ratio were associated with increased expression of proinflammatory cytokines and vascular endothelial growth factor and inhibition of protective inhibitory cytokines in patients with less favorable 5-year cancer outcomes. Meaning These findings suggest that less favorable colon cancer outcomes associated with low skeletal muscle area and high visceral to total fat ratio were also associated with increased expression of proinflammatory cytokines and vascular endothelial growth factor and lower levels of protective inhibitory cytokines., This cohort study examines associations among body composition profiles, inflammatory marker expressions, and 5-year colon cancer outcomes., Importance Obesity, particularly visceral obesity and sarcopenia, are poor prognostic indicators in colon cancer. Objectives To explore the association between body composition profiles and 5-year colon cancer outcomes and delineate the associated underlying inflammatory processes. Design, Setting, and Participants This multicenter translational cohort study included patients with nonmetastatic colon cancer who did not have underlying chronic inflammatory disorders and were not receiving anti-inflammatory drugs referred to tertiary cancer centers from 2009 to 2015. Preoperative acute phase proteins (white cell count, C-reactive protein, and albumin), cytokines (interleukin [IL]-1b, IL-2, IL-6, IL-10, interferon γ, and tumor necrosis factor α), vascular endothelial growth factor (VEGF), and cell surface receptor expression levels (CD11b and CD14) were measured. All patients underwent follow-up for at least 5 years. Data were analyzed in December 2020. Exposure Nonmetastatic colon cancer. Main Outcomes and Measures The associations of body composition profiles with 5-year cancer recurrence and disease-specific mortality were analyzed using Mantel Cox log-rank test and Kaplan-Meier curves. Results A total of 28 patients were included (median [interquartile range] age, 67 [58-72] years; 22 [78.6%] men). Low skeletal muscle area (SMA) and high visceral to total fat ratio were associated with poor clinical and oncological outcomes, including increased 5-year recurrence (low SMA: hazard ratio [HR], 2.30 [95% CI, 1.41-2.89]; P = .04; high visceral to total fat ratio: HR, 5.78 [95% CI, 3.66-7.95]; P = .02). High visceral to total fat ratio was associated with increased 5-year disease-specific mortality (HR, 5.92 [95% CI, 4.04-8.00]; P = .02). Patients with low SMA who developed a cancer recurrence, compared with those who did not, had higher C-reactive protein (mean [SD], 31.24 [6.95] mg/dL vs 8.11 [0.58] mg/dL; P = .003), IL-6 (mean [SD], 1.93 [1.16] ng/mL vs 0.88 [0.14] ng/mL; P = .004), VEGF (mean [SD], 310.03 [122.66] ng/mL vs 176.12 [22.94] ng/mL; P = .007), and CD14 (mean [SD], 521.23 [302.02] ng/mL vs 322.07 [98.35] ng/mL; P = .03) expression and lower albumin (mean [SD], 3.8 [0.6] g/dL vs 43.50 [3.69] g/dL; P = .01), IL-2 (mean [SD], 0.45 [0.25] ng/mL vs 0.94 [0.43] ng/mL; P

This article discloses part of an invention on plug-and-play converter-level on -state voltage measurement methods for power semiconductor devices. To exclude the external power supply required in on -state voltage measurement circuits, a self-power solution is proposed to provide the required bidirectional low-voltage power sources. The application of the measurement circuit with the proposed self-power solution is demonstrated for a single-switch, a single-phase inverter, and a three-phase inverter.

Background Low handgrip strength (HGS) is independently associated with a higher exacerbation risk in stable chronic obstructive pulmonary disease (COPD); however, the relationship between HGS while being admitted for COPD exacerbation and further exacerbation risk after discharge remains unclear. Methods We enrolled patients admitted for COPD exacerbation between January 2018 and June 2019. HGS tests were done within 3 days after admission. The primary endpoint was exacerbations within 12 months after the index admission, which needed emergency room visits or hospital admission. We analyzed the relationships among demographics, HGS, pulmonary function parameters, and acute exacerbation events. Results Among 43 enrolled patients, 31 (72.1%) participants (HGSw) had HGS weakness (22.1 ± 4.1 kg). The other 12 (27.9%) participants (non-HGSw) had the strength of handgrips 33.7 ± 3.1 kg. HGSw group showed a significantly higher rate of emergency room visits within 6, 9, and 12 months after the index admission than non-HGSw group (0.81 ± 1.30 vs. 0.08 ± 0.29, p = 0.045; 1.26 ± 1.59 vs. 0.17 ± 0.38, P = 0.019; 1.48 ± 1.86 vs. 0.25 ± 0.62, P = 0.027, respectively). There was a trend to have higher admission rate within 9 and 12 months in HGSw group, which did not achieve statistical significance (0.77 ± 1.38 vs. 0.08 ± 0.29, P = 0.064; 0.94 ± 1.56 vs. 0.08 ± 0.29, P = 0.062, respectively). Conclusions HGS weakness measured upon admission for COPD exacerbation was associated with a higher risk of exacerbation in the next year. Trial registration ClinicalTrials.gov Identifier: NCT04885933.

This paper proposes an intelligent seamless transition controller for smooth transition between grid-connected (GC) and standalone modes of distributed generation (DG) units in the grid. The development of this seamless controller contributes to two main processes in the transition modes: the synchronization process and an islanding process. For the synchronization process, the stationary reference frame phase-locked loop (SRF-PLL) associated with the voltage source inverter (VSI) is modified using the frequency, voltage deviation, and phase angle information. Furthermore, the islanding process is classified as intentional and unintentional islanding scenarios for achieving efficient transition control. Here, the intentional islanding process is achieved with the information that is available in the system due to the planned disconnection. For the unintentional islanding process, a fuzzy inference system (FIS) is used to modify the conventional droop control using the information of change in active power, voltage, and frequency. To identify the action of the proposed approach during the transition process, numerical simulations are conducted with the hardware-in-loop (HIL) simulator by developing a 10kWp three-phase grid-connected DG system. The results identified the efficient control of the VSI for both islanding and grid connection processes. In the islanding conditions, the proposed controller provides advantage with less detection and disconnection time, and during synchronization, it instantly minimizes the phase-angle deviation to achieve efficient control.

This article proposes a capacitor voltage ripple reduction method used for a modular multilevel cascade converter (MMCC) with single delta bridge cells (SDBC), by applying a third harmonic zero-sequence current. A practical case study on an 80 MVar/33 kV MMCC-SDBC-based STATCOM is used to demonstrate the method. The impact of the third harmonic zero-sequence current level of the capacitor ripple reduction and the electrothermal stresses on insulated gate bipolar transistor modules are analyzed. An optimal parameter of the current level is obtained by compromising the above-mentioned performance factors. The obtained result shows that the required capacitance, as well as the capacitor bank volume, is reduced by 20% without increasing the total power semiconductor losses by using the proposed method.

One of the next challenges for modular multilevel converters (MMCs) is how to the size the critical components to their limits with reduced design margins, while at the same time fulfilling the reliability target. To do it confidently, better thermal modeling with quantitative uncertainty analysis is necessary to support the decision-making during the product design stage. Regarding the conversion of long-term mission profiles into thermal profiles for reliability evaluation, this paper proposes a computationally efficient thermal modeling method for insulated-gate bipolar transistor modules in MMCs. The proposed method considers the impact of the inherent thermal unbalance and has minimum computation with quantitative error analysis. Finally, both simulations and experiments have verified the theoretical results.

Objectives: To assess the prevalence of hepatitis B virus (HBV) infection among married individuals and to analyze the associated risk factors of HBV infection in vaccinated and unvaccinated groups in 2006 and 2014. Methods: Information of married individuals aged over 16 y with a clear HBV vaccination status was extracted from the database constructed by the Beijing Center for Disease Prevention and Control from population-based investigation. A structured questionnaire was employed to collect demographic information, vaccinated history, and other related influence information of HBV of participants. Pearson chi-square test, Fisher's test, and logistic regression were used to explore the risk factors of HBV infection. Results: A total of 2874 individuals in 2006 and 1622 individuals in 2014 were enrolled in our study. The mean age of individuals was 49.30 and 46.68 y in 2006 and 2014, respectively. The overall positive rates of HBsAg, anti-HBc, and single anti-HBs were 4.80%, 43.01%, and 5.78% in 2006, which were 4.69%, 38.22%, and 14.18% in 2014, respectively. For vaccinated individuals, age was significantly correlated with anti-HBc in 2014 (40 < age ≤50 versus age ≤30, relative risk (RR) = 3.03, 95% confidence interval (95%CI) = 1.04–8.84). Gender [male versus female, RR = 0.60, 95%CI = 0.36–1.00 (2006); RR = 0.71, 95%CI = 0.52–0.97 (2014)] and age (in 2006) were found to be significantly associated with single anti-HBs. For unvaccinated individuals, HBsAg positivity was statistically significant correlated with gender [RR = 1.47, 95%CI = 1.04–2.06, in 2006], residence (urban versus rural, RR = 0.40, 95%CI = 0.24–0.67, in 2006; RR = 0.58, 95%CI = 0.34–0.99, in 2014), sharing syringes [RR = 3.75, 95%CI = 1.33–10.63 (in 2006); RR = 2.07, 95%CI = 1.26–3.41 (in 2014)], infected wives (RR = 1.97, 95%CI = 1.28–3.05, in 2006), and infected husbands (RR = 2.19, 95%CI = 1.25–3.82, in 2006). Anti-HBc positivity was significantly associated with gender [RR = 1.19, 95%CI = 1.10–1.30 (in 2006); RR = 1.24, 95%CI = 1.09–1.40 (in 2014)], age (in 2006 and 2014), endoscopic medicine treatment [RR = 1.16, 95%CI = 1.03–1.32 (in 2006), RR = 1.21, 95%CI = 1.01–1.45 (in 2014)], sharing syringes (RR = 1.43, 95%CI = 1.25–1.64, in 2014), body piercing (RR = 0.84, 95%CI = 0.75–0.93, in 2006), infected wives (RR = 1.32, 95%CI = 1.18–1.47, in 2006), and infected husbands (RR = 1.39, 95%CI = 1.22–1.59, in 2006). Anti-HBs positivity was associated with age (in 2006 and 2014). Conclusions: Prevalence of HBV infection was lower in 2014 than in 2006 according to HBsAg and anti-HBc positivity. Unvaccinated individuals faced much more risk of HBV infection than those of vaccinated.

Modular multilevel cascade converters (MMCCs) are becoming attractive solutions as high-voltage Static Synchronous Compensators (STATCOMs) for power plants in renewable energy generation, in order to satisfy the strict grid codes under both normal and grid fault conditions. This paper investigates the performances of four potentially used configurations of the MMCC family for the STATCOM in large-scale offshore wind power plants, with special focus on asymmetrical low-voltage ride through capability under grid faults. The specifications and the sizing of components of each type of practical 80-MVar/33-kV-scaled MMCC-STATCOM are carefully designed and compared. The total cost and volume are compared based on the total power semiconductor chip area and the total energy stored in the passive components. Asymmetrical reactive power delivering operation of the MMCC family considering the dc-link capacitor voltage-balancing method is solved mathematically in order to quantitatively understand the performance limitations and behaviors. The electrothermal stress of the power modules used in each type of the MMCC for a practical 80-MVar/33-kV-scaled STATCOM is analyzed. The asymmetrical reactive power capability of the MMCC solutions is compared under different scenarios of grid faults, while considering the device temperature limits as well as voltage saturation. It is found that the MMCC configuration with double-star bridge cells becomes the most attractive circuit configuration for the STATCOM application based on the obtained results.

This paper proposes a new series resonant DC-DC converter with four configurable operation states depending on the input voltage and output voltage levels. It suits well for the DC-DC stage of grid-connected photovoltaic (PV) systems with a wide-input voltage range and different grid voltage levels, i.e., 110/120 V and 220/230/240 V. The proposed converter consists of a dual-bridge structure on the primary side and a configurable half- or full-bridge rectifier on the secondary side. The root-mean-square (RMS) currents are kept low over a fourfold voltage-gain range; The primary-side MOSFETs and secondary-side diodes can achieve zero-voltage switching (ZVS) on and zero-current switching (ZCS) off, respectively. Therefore, the converter can maintain high efficiencies over a wide voltage gain range. A fixed-frequency pulse width modulated (PWM) control scheme is applied to the proposed converter, which makes the gain characteristics independent of the magnetizing inductance and thereby simplifies the design optimization of the resonant tank. The converter topology and operation principle are first described. Then the characteristics, i.e., the dc voltage gain, soft-switching, and RMS currents, are detailed before a performance comparison with conventional resonant topologies is carried out. Furthermore, the design guidelines of the proposed converter are also presented. Finally, the experimental results from a 500-W converter prototype verify feasibility of the proposed converter.

Background: Cognitive impairment is a frequent and often debilitating consequence of stroke. This single-blinded randomized controlled trial examined the therapeutic benefits of continuous theta burst stimulation (cTBS) for patients with post-stroke cognitive impairment (PSCI). Methods: Twenty patients with PSCI were randomly and equally allocated to cTBS and sham cTBS groups. Groups received the indicated treatments five consecutive days per week for 2 weeks (10 sessions) plus 10 sessions of computer-assisted cognitive training. The primary outcomes were changes in Alzheimer’s Disease Assessment Scale-cognitive subscale (ADAS-cog) score and analysis along the perivascular space (ALPS) index. Results: The post-intervention change in ADAS-cog score from baseline was significantly greater in the cTBS group than the sham cTBS group (-7.7 ± 3.8 vs. -3.7 ± 1.5, t = -3.096, P = 0.006). Change in ALPS index from baseline was also greater in the cTBS group (0.182 ± 0.097 vs. 0.093 ± 0.080, t = 2.236, P = 0.038). Conclusion: Continuous theta burst stimulation can improve cognitive outcome and enhance ALPS. Enhanced waste clearance via the glymphatic system induced by cTBS may contribute to improved cognitive function following stroke.Clinical Trial Registration URL: http://www.chictr.org.cn. ChiCTR1800017997. Registered August 25, 2018, retrospectively registered.

This is a preprint version of the manuscript submitted to IEEE on June 4, 2020.This paper gives an overview of the Artificial Intelligence (AI) applications for power electronic systems. The three distinctive life-cycle phases, design, control, and maintenance are correlated with one or more tasks to be addressed by AI, including optimization, classification, regression, and data structure exploration. The applications of four categories of AI are discussed, which are expert system, fuzzy logic, metaheuristic method, and machine learning. More than 500 publications have been reviewed to identify the common understandings, practical implementation challenges, and research opportunities in the application of AI for power electronics.

The epidemic of the novel, pathogenic SARS-coronavirus 2 (SARS-CoV-2) in the world pose a global health emergency. Cancer has been identified as a risk factor for the novel Coronavirus disease 2019 (COVID-19). The ACE2 and TMPRSS2 have been implicated in SARS-CoV-2 infection for mediating viral entry into the host cell. However, a systematic analysis of aberrant expression of ACE2 and TMPRSS2 was not yet reported in multiple human cancers. Here, we analyzed gene expression of ACE2 and TMPRSS2 across 31 types of tumors. Notably, overexpression of ACE2 and TMPRSS2 have been observed in colorectal cancer including colon adenocarcinoma (COAD), and rectum adenocarcinoma (READ). In addition, the colorectal tumors with upregulated gene expressing presented with decreased DNA methylation levels. DNA methylation might be one of the reasons for abnormal expression of ACE2 and TMPRSS2. Conclusively, colorectal cancer was the only cancer with the upregulated expression of ACE2 and TMPRSS2. More care of colorectal cancer patients is needed in multiple cancers affected by the COVID-19 outbreak.

Condition monitoring is a proactive measure to realize operation optimization, predictive maintenance, and high availability of Power Electronic Systems (PES). It is demanded by reliability-, safety-, or availability-critical applications. The core of condition monitoring is a prediction based on historical and present information. Artificial Intelligence (AI) could play a role in addressing optimization, regression, and classification problems in predicting the operation or health status of PES. Besides AI algorithms, quality data collection, objective formulation, and result validation require an in-depth understanding of the PES. The nexus between PES and AI expects to create overarching effects in the condition monitoring area. This article presents exploratory efforts in the data-driven condition monitoring of PES in the view of existing challenges and emerging opportunities.

Orthocyclic winding in magnetic components is common in both laboratory prototyping and mass production, especially for round wires with curved edges. However, its impact on winding parasitics, i.e., winding capacitance, ac resistance, and leakage inductance, has not been systematically investigated yet. Omission or inaccurate calculation of these parameters leads to current ringing, additional losses, and even abnormal operations. In this article, three modified formulas for parasitics of orthocyclic windings are proposed, and the impacts of orthocyclic windings are comprehensively studied. Magnetic field distortion and air-gap effect are analyzed and compensated. The formulas are verified by finite-element method (FEM) simulation and experimental results. Finally, normal and orthocyclic windings are compared, and conclusions are listed to illustrate the impact of orthocyclic windings on parasitics.

Condition monitoring (CM) methods applied for power electronics can provide effective information for predictive maintenance and prevent unexpected system downtime. This paper proposes a non-invasive and in-situ CM method for capacitors in modular multilevel converters. Unlike the conventional methods that monitor low-frequency signals, the proposed method focuses on high-frequency transient analysis. By analyzing the transient voltage at the capacitor's charging moment with wavelet decomposition, the proposed method can estimate the capacitor's equivalent series resistance in situ. Moreover, the proposed method based on high-frequency transients is decoupled from system operating states, while the conventional low-frequency signals are often affected by operations (e.g., loads, environments, etc.). Finally, the effectiveness of the proposed method has been validated in a 14kW case study by simulation.

This letter proposes a simplified converter-level on-state voltage measurement circuit for power semiconductor devices, without an external power supply and self-power circuit. It has a reduced component count and circuit complexity, and retains the plug-and-play feature, comparable measurement accuracy, and dynamic response as recently reported methods. A proof-of-concept prototype is developed and tested for a three-phase inverter application.

The dc-link capacitor is considered as a weak component in photovoltaic (PV) inverter systems and its reliability needs to be evaluated and tested during the product development. Conventional reliability testing methods for capacitors are typically carried out under constant loading conditions, which do not reflect the real operating conditions (e.g., mission profile) of the dc-link capacitor in PV inverters. To address this issue, a new reliability testing concept for the dc-link capacitor in PV inverters is proposed in this article. In contrast to the conventional method, the proposed reliability testing method designs the test profile through the modification of the original mission profile (e.g., solar irradiance and ambient temperature) in order to maintain the test condition as close to the real application as possible. A certain acceleration factor is applied during the mission profile modification based on the lifetime model of the capacitor, in order to increase the thermal stress of the dc-link capacitor during test, and thereby effectively reduce the testing time.

This letter proposes a safe operating area (SOA) concept for film capacitors in dc-link applications. The SOA is presented by capacitor voltage and ripple current, considering the impact of ambient temperature, degradation, and parameter variance. The theoretical derivations and proof-of-concept experimental verifications are given.

Nowadays, transformerless PV inverters (TPVI) are more popular due to its excellent features such as lower in size, cost and higher in efficiency, as compared with conventional inverters. Undoubtedly it leads dangerous leakage current via stray capacitors to the ground, which results higher current ripples and problems related to electromagnetic interference (EMI). Therefore, a several configurations have been proposed with reduced leakage current and constant common-mode voltage (CMV). In this paper a modified H-bridge structure is proposed with rectifier circuit at mid-point of the dc-link capacitor to keep constant CMV in the whole grid cycle namely M-HB topology. The theoretical findings of the MHB inverter are tested through simulation results. At the end a fair comparative analysis is presented.

Background Myocardial dysfunction is an important adverse factor of hemorrhagic shock that induces refractory hypotension, and post-hemorrhagic shock mesenteric lymph (PHSML) return is involved in this adverse effect. This study investigated whether mesenteric lymph drainage (MLD) improves PHSML return-induced cardiac contractile dysfunction via the restoration of cardiomyocyte calcium sensitivity. Materials and methods A hemorrhage shock model was established by using a controlled hemorrhage through the femoral artery that maintained a mean arterial pressure of 40 ± 2 mmHg for 3 h. MLD and mesenteric lymph duct ligation (MLDL) were performed from 1 to 3 h during hypotension. The papillary muscles of the heart were collected for measurement of calmodulin expression and for determining contractile responses to either isoprenaline or calcium. Results The results showed that either MLD or MLDL reversed the hemorrhagic shock-induced downregulation of calmodulin expression, a marker protein of cardiomyocyte calcium sensitization, in papillary muscles. MLD also improved the decreased contractile response and ±df/dt of the papillary muscle strip to gradient isoprenaline or calcium caused by hemorrhagic shock. Conclusion These findings indicate that increased cardiac contractibility may be associated with the restoration of calcium sensitivity produced by PHSML drainage.

A high end-fire gain, low-profile surface wave antenna with capacitive feed structure is presented in this paper. The proposed dielectric-metal surface wave antenna is composed of a dielectric slab that is mounted on a metal carrier and a low-profile feed structure. The feed structure is composed of a monopole radiation pin that is loaded with a circular metal plate and a grounding pin. The profile height of the antenna is only one-tenth of the operating wavelength. With a good end-fire performance and low profile, the antenna is very suitable to be conformally mounted on the surface of flight vehicles. The proposed antenna was designed and manufactured at the center frequency of 6 GHz. Measured results demonstrated that the proposed antenna had a bandwidth of 7.33%, ranging from 5.89 to 6.33 GHz, and the antenna reached a high gain of 9.76 dBi with a length of 122.96 mm (2.45 λ) in the end-fire direction.

In this paper, the power losses of three-level active neutral-point-clamped (3L-ANPC) inverters fully utilizing silicon-carbide (SiC) MOSFETs are studied and compared under three typically modulation schemes (i.e., the outer mode, inner mode, and full mode). Double-pulse tests (DPTs) are performed on a 3L-ANPC inverter prototype to evaluate the switching losses of SiC MOSFETs. The overall conversion losses subject to the three modulation schemes are investigated considering device junction temperatures. Accordingly, loss distributions among SiC devices are obtained, and the devices subject to the most significant electro-thermal stresses are identified. A power-loss comparison exhibits a comparable loss performance between the outer-mode and inner-mode modulation methods, while the full-mode loss characteristic is quite dependent on its loading condition. Finally, the theoretical finding presented in this work are validated through experimental measurements of the conversion efficiencies.

Background: It has been convincingly suggested that a close correlation exists between the incidence of hepatocellular carcinoma (HCC) and cigarette smoking. However, the underlying effect of smoking on HCC is not clear. Methods: A binary unconditional logistic regression was used for the data on a total of 300 cases and 612 controls. The approach of functional analysis of separated alleles in yeast and direct sequencing of TP53 mutations were applied to analyze the p53 status in the HCC group. The relationship between p53 mutation at serine 249 (p53-RS) and smoking was assessed. Quantitative reverse transcription PCR was employed for the evaluation to transcriptional activity of p53 and p53-RS. Results: Smoking was linked to the risk of HCC with an increased dose-response effect. Moreover, among subjects who did not drink, the risks of HCC were significantly increased for smokers between HCC and controls. Besides, there was an increase in the number of HCC in smokers compared to nonsmokers after exclusion of HBV and/or HCV infection. Also, a significant difference was observed in the incidence of p53-RS between smokers and nonsmokers the HCC group. Furthermore, the p53-RS transcriptional activity was significantly increased in tumor tissues. Conclusions: It strongly demonstrated that tobacco smoking is positively and independently associated with HCC, which may be attributed to p53-RS and its gain of function.

OBJECTIVE To investigate the effectiveness of molding custom-made insoles for female patients with foot pain. METHODS The study included 20 patients whose insoles were prescribed according to biomechanical evaluations and molded by repositioning the subtalar joint in its neutral position using a simple set of tools. Plantar biomechanics were measured under the following conditions: static stand, walking at self-comfortable walking speed (CWS) barefoot, walking in patient owned running shoes, and walking in running shoes plus insoles. Each patient's upper arm isometric muscle strength and subjective feelings before and after the insole intervention were assessed. RESULTS The molded insoles increased plantar contact area both during static standing and walking at CWS compared to the barefoot condition. The insoles also had more evenly distributed plantar contact area and loading rate, with the changes in the medial arch area being most significant. Moreover, the custom-made insole intervention immediately increased maximum resistance and duration of bilateral upper arms, as well as improved foot comfort, especially at the medial arch area during single leg squat tests. CONCLUSION Molding custom-made insoles by repositioning the subtalar joint in its neutral position can be accomplished with a simple set of tools, making this method highly applicable for a majority of less developed regions. Insoles molded using this method are effective in immediately improving plantar biomechanics disorders and enhancing isometric upper muscle performance in female patients with foot pain.

Background The major risk factors for hepatocellular carcinoma (HCC) are known to be hepatitis b virus (HBV) infection and aflatoxin B1(AFB1) exposure. However, there is still controversy about whether smoking is related to HCC.Methods A binary unconditional logistic regression was used for the data about a total of 300 cases and 612 controls. The approach of functional analysis of separated alleles in yeast (FASAY) was applied to analyze p53 status in HCC group. The relationship between p53 mutation at Serine 249 (p53-RS) and smoking was assessed. Quantitative reverse-transcription PCR (qRT-PCR) was employed for the evaluation to transcriptional activity of p53 and p53-RS. Results Smoking was linked to the risk of HCC with an increased dose-response effect. Moreover, among subjects without alcohol drinker, the risks of HCC were significantly increased for smokers between HCC and controls. Besides, there was an increase in the number of HCC in smokers compared to non-smokers after exclusion of HBV and/or HCV infection. Also, a significant difference was observed about p53-RS between smokers and nonsmokers. Furthermore, the p53-RS transcriptional activity was significantly increased in tumor tissues.Conclusions It demonstrated that tobacco smoking is positively and independently associated with HCC, which may be attributed to p53-RS and its gain of function.

Two sets of hybrid constructed wetlands (HCWs) with the first-stage aeration were used to treat actual domestic sewage in this paper, where the effects of three important factors of aeration mode, hydraulic loading rates (HLR), and aeration volume on the removal of pollutants in both HCWs were studied in contrasts. In addition, the pollutant removal efficiency, the contribution of plants, and the characteristics of biofilm in both HCWs were explored. The results of 250-day experiment showed that the TN removal capacity of HCW combining vertical flow CW with horizontal flow CW (VF-HF) was better than HCW’s converse combination (HF-VF) in treatingsewage, while the removal efficiency of COD and NH4+-N were similar, and the concentrations of TN and COD in the effluent of VF-HF could successfully meet the National discharge requirements. Compared with the continuous aeration, the intermittent aeration only had a little effect on the removal of COD and NH4+-N, but could improve TN removal performance in both HCWs. Meanwhile, increasing the aeration volume was beneficial to remove NH4+-N but not TN in HCWs. In addition, although the pollutant removal performances in both HCWs were impacted, the removal capacity of TN in VF-HF was only affected a little, when HLR was increased by 50%. The contribution of plants’ uptake accounted for about 10% to nitrogen removal and 20% to phosphorus removal in both HCWs. The biomass at the filler surface near the plant rhizosphere was greater than that in the non-rhizosphere zones, and the impact of plant rhizosphere on the nitrification activity of biofilm was significantly greater than that on denitrification activity in both HCWs.

Background: Although patients with end-stage renal disease (ESRD) receiving dialysis are considered a high risk group for tuberculosis, the optimal treatment regimen for latent tuberculosis infection (LTBI) had not been studied yet. Aim: To compare the two regimens – twelve-dose weekly rifapentine plus isoniazid (3HP) and nine-month daily isoniazid (9H) for LTBI among patients under maintenance dialysis, with emphasis on completion rate and adverse drug reactions (ADR). Method: Since September 2014, we prospectively followed ESRD patients screened and treated for LTBI in three medical centers and one regional hospital in north Taiwan. Patients received 3HP or 9H for LTBI treatment if clinically suitable. Patients on 3HP were obliged to join directly observed preventive therapy program (DOPT), while those on 9H received DOPT based on availability. Laboratory results, ADR, reasons for discontinuation were recorded. Results: 88 ESRD patients and 91 treatment courses (9H n=41, 3HP n=50) were recorded. The completion rate was 50% (16/32) for 9H and 81.3% (39/48) for 3HP (p=0.003). The leading cause of incomplete treatment was patient refusal for 9H (50%) and ADR for 3HP (55.6%). Malaise was the most frequently reported ADR in both regimens. Higher rate of ≥grade 2 ADRs were reported among 3HP regimen (45.8% vs 15.8%, p=0.003). AST (aspartate aminotransaminase) elevation Conclusion: Despite higher rate of ADR using 3HP regimen, ESRD patients on maintenance dialysis could had higher rate of completion as compared with 9H.

The main task of object detection is to identify and locate interested objects from still images or video sequences. It is one of the key tasks in the field of computer vision. However, the object usually has variable factors in brightness, shape, occlusion and so on, and is interfered by various and complex environmental factors, which makes the research opportunities and challenges of object detection algorithm coexist. In this paper, a main frame of object detection algorithm based on convolutional neural network is studied, which is based on regression. We propose a real-time object detection algorithm based on fully convolution network, which aims to solve the problems of low detection accuracy and poor location accuracy of objects in regression method. The innovation is that the proposed fully convolution network increases the detection flexibility of the model because it is not affected by the input scale. At the same time, we propose a multi feature fusion and multi border prediction strategy, which effectively improves the detection accuracy of small objects. In order to prove the effectiveness of the proposed algorithm, we use PASCAL VOC data set to carry out object detection experiments. In this paper, the accuracy of each object category and the average accuracy of all categories are calculated. Experiments show that the performance of the multi feature fusion algorithm based on the fully convolution network is better than that based on the regression idea such as YOLO, and more than 10% higher than that of the YOLO model.

This letter proposes a new submodule capacitor condition monitoring method for modular multilevel converters (MMCs) based on the dc-side start-up procedure. During this process, the MMC can be simplified into an RC charging circuit, and the submodule capacitance can be estimated by investigating its relationship with the phase current and submodule voltage. Several practical issues related to the implementation, advantages, and limitations of the proposed method are presented as well. In order to validate the method, a series of experiments with different submodule capacitances are conducted based on a three-phase MMC platform. Experimental results confirm the effectiveness and feasibility of the proposed method.

In the thermal analysis of a Modular Multilevel Converter (MMC) system, one of the challenges is to model the heat sources and thermal paths across large spatial scales, i.e., from a tiny power semiconductor chip at square millimeters to the whole converter system up to several thousand cubic meters. Without good understanding of the dissimilarity of thermal behaviors under different spatial scales, conventional thermal models usually lead to either considerable modeling errors or heavy computational burden. In this paper, a hierarchical decomposition method is proposed to do the system-level thermal modeling of the MMC. At Sub-Module(SM) level, ethe junction/hotspot-to-local ambient thermal model of devices is established, where Thermal Cross-Coupling (TCC) effects among different devices in the SM are considered. At converter-level, thermal model is obtained to depict mutual European influences Unionamong the SMs in the MMC. A 15-kVA MMC prototype provides the experimental verifications at last.

Purpose Mycobacterium avium complex-lung disease (MAC-LD) is increasing worldwide and may progress to cause mortality significantly. However, for patients without initial treatment at diagnosis, the survival outcomes and predictors of mortality remain unclear. Methods From 2011 to 2017, MAC-LD patients at two medical centers in Taiwan were screened, and those who received MAC treatment at the initial were excluded. The clinical course and characteristics were recorded. Cox regression analysis and receiver operating characteristic (ROC) curves were performed to assess risk factors of mortality within 4 years. Results We included 123 MAC-LD patients without initial MAC treatment. The mean follow-up period was 4.15 ± 2.52 years. Twenty-two (17.9%) patients died within four years. Multivariate analysis showed that four independent factors related to 4-year mortality were consolidation pattern (hazard ratio [HR] 6.0, 95% confidence interval [2.3–15.5]), radiographic score > 6 (HR:11.0 [4.0–31.1]), radiographic deterioration within two years (HR: 5.2 [2.1–13.1]) and no MAC treatment during follow up (HR: 6.5 [1.3–31.1]). The areas under the ROC curves for prediction of 4-year mortality for the combination of consolidation and radiographic score >6, the two factors plus radiographic progression, the two plus no MAC treatment, and the combination of the four factors were 0.702, 0.798, 0.758, and 0.835, respectively. Conclusions The four-year mortality rate in MAC-LD without initial treatment is high. Presence of consolidation pattern and radiographic score >6 at initial visit, radiographic deterioration and no treatment during follow-up were risk factors of 4-year mortality in initially untreated MAC-LD.

Planar transformers are widely used in high- frequency high power density power electronic converters. With the demands of miniaturization, more detailed analysis of thermal stress of the transformers is necessary to enhance its reliability. Due to the strong coupling between the power loss and the distribution of the temperature, a model-based design considering the thermal issue together with the winding configuration is essential. This paper presents a thermal modelling method for planar transformers considering different winding configurations and internal uneven power loss distribution. The temperature distributions of different locations in the transformer windings and cores are identified. The impact of the winding structure on the thermal behavior is analyzed. Finally, A case study with a simplified analytical model, computational fluid dynamic (CFD) simulations, and experimental results are presented for verification.