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A novel asymmetric interior permanent magnet (AIPM) machine is proposed in this paper for electric vehicle application. It has a skewed V-shape permanent magnet (PM) cavity, two PMs with different dimensions and an additional flux barrier outside the V-shape cavity in each pole. This asymmetric rotor topology can inherently utilize the magnetic-field-shifting (MFS) effect to reduce the current angle difference between the maximum PM and reluctance torque components, thereby enhancing the maximum synthetic torque with the same PM usage. The influences of cavity positions in the proposed AIPM and an existing AIPM with extra flux barrier inside the V-shape cavity are investigated and compared using finite element analysis. It is found that the proposed structure with outside flux barrier has higher average torque than the one with inside flux barrier. Both AIPM topologies are designed with the same stator, rotor diameter, and PM usage as the conventional V-shape IPM benchmark for Prius 2010. Electromagnetic, mechanical and steady-state thermal performance of three machines are compared. The results confirm that the proposed AIPM machine can achieve significant torque enhancement due to utilizing MFS effect, compared with the existing AIPM and the IPM benchmark. Finally, a small prototype of the proposed AIPM machine is designed, manufactured and tested to validate the FE analysis.

The behavior of displacement field due to a screw dislocation is similar to the angular basis function (ABF) Arg(z). It is different from the radial basis function (RBF) ln(r) that is used to describe the velocity potential of a sink or source. Nevertheless, the complex-valued fundamental solution ln(z) contains the two parts of RBF ln(r) and ABF Arg(z). In this paper, not only the RBF in the null-field boundary integral equation (BIE) but also the ABF for the screw dislocation are employed to study the interaction between a screw dislocation and an elastic elliptical inhomogeneity. This problem is decomposed into a free field with a screw dislocation and a boundary value problem containing an elliptical inhomogeneity. The boundary value problem is solved by using the RBF and the null-field BIE. Since the geometric shape is an ellipse, the degenerate kernel is expanded to a series form under the elliptical coordinates, while the unknown boundary densities are expanded to eigenfunctions. By combining the degenerate kernel and the null-field BIE, the boundary value problem can be easily solved. The inconsistency between Sendeckyj [1] and Gong & Meguid [2] for the problem was also found by using the present approach. The error in [2] was also printed out. Finally, some examples are demonstrated to verify the validity of the present approach.

Backgrounds Chronic kidney disease (CKD) is underdiagnosed in children with congenital heart disease (CHD). Our aim was to study the incidence of CKD in CHD children and identify risk factors for CKD. Methods CHD patients were enrolled from the Kaohsiung Veterans General Hospital database between 2010 and 2019. Patient age at enrollment was age at first visit to the hospital. The end of follow-up was marked by the last measurement of serum creatinine, urine protein-to-creatinine ratio (UPCR), or urine microalbumin-to-creatinine ratio (UACR) after enrollment, and only patients who underwent the aforementioned tests in 2 different years were included. Patients with an estimated glomerular filtration rate (eGFR) < 90 mL/min/1.73m2 were diagnosed as having CKD and were further classified into clinically recognized CKD (CR-CKD, defined as eGFR 2, UPCR >0.5, or UACR >30 mg/g) and non-clinically recognized CKD (NCR-CKD). Their demographic data, CHD category, heart surgery types, medications, and contrast-related examinations during follow-up were collected. Results The study included 359 CHD patients, of whom 167 (46.5%) developed CKD (18 patients with CR-CKD and 341 with NCR-CKD). Patients with CR-CKD were significantly older at enrollment than patients with NCR-CKD. Corrective heart surgery may be a protective factor for CKD. Furthermore, cyanotic heart disease, two or more image-related contrast exposures, and diuretic use may be associated with CKD. Conclusion CHD patients have a high incidence of CKD. The early detection of CKD and prompt corrective heart surgery for CHD may be beneficial for kidney function. Graphical abstract

The 6-slot/2-pole (6s/2p) permanent magnet motors with a diametrically magnetized PM rotor are popular for high speed application. Meanwhile, toroidal winding can not only reduce end-winding length but also eliminate unbalanced magnetic force for short axial length motors. Therefore, the electromagnetic performance of a 6s/2p high speed PM (HSPM) motor with toroidal windings is firstly analyzed, including air-gap flux density, flux linkage, back-EMF, cogging torque and electromagnetic torque. Then, considering modular design for auto-manufacturing, the influence of stator gap and misalignment on the electromagnetic performance is investigated. It shows that the stator gap results in unbalanced three phase back-EMFs, not only amplitudes, but also phase angles. The stator gap increases the equivalent air-gap length and PM flux leakage, which leads to lower air-gap flux density, back-EMF, and average torque. Moreover, the stator gap results in asymmetric air-gap length, which results in large cogging torque. Further, it shows that the misalignment of two stator parts mainly affects the uneven equivalent air-gap length and symmetry of winding configuration, which leads to unbalanced three phase back-EMFs, especially phase angles, and self- and mutual-inductances, as well as rotor PM loss. Experimental results of a prototype motor with/without stator gap and/or misalignment are given to validate the finite element predicted analyses.

The hot-wall metal-organic chemical vapor deposition (MOCVD), previously shown to enable superior III-nitride material quality and high performance devices, has been explored for Mg doping of GaN. We have investigated the Mg incorporation in a wide doping range ($2.45\times{10}^{18}~cm^{-3}$ up to $1.10\times{10}^{20}~cm^{-3}$) and demonstrate GaN:Mg with low background impurity concentrations under optimized growth conditions. Dopant and impurity levels are discussed in view of Ga supersaturation which provides a unified concept to explain the complexity of growth conditions impact on Mg acceptor incorporation and compensation. The results are analysed in relation to the extended defects, revealed by scanning transmission electron microscopy (STEM), X-ray diffraction (XRD), and surface morphology, and in correlation with the electrical properties obtained by Hall effect and capacitance-voltage (C-V) measurements. This allows to establish a comprehensive picture of GaN:Mg growth by hot-wall MOCVD providing guidance for growth parameters optimization depending on the targeted application. We show that substantially lower H concentration as compared to Mg acceptors can be achieved in GaN:Mg without any in-situ or post-growth annealing resulting in p-type conductivity in as-grown material. State-of-the-art $p$-GaN layers with a low-resistivity and a high free-hole density (0.77 $\Omega$.cm and $8.4\times{10}^{17}~cm^{-3}$, respectively) are obtained after post-growth annealing demonstrating the viability of hot-wall MOCVD for growth of power electronic device structures., Comment: main: 11 pages, 8 figures - supplementary: 2 pages, 3 figures

This brief is devoted to the predesigned motion trajectory-based finite time dynamic positioning (DP) control for a marine surface vehicle (MSV) with unknown external disturbances. Firstly, a preset motion trajectory is presented through establishing the relationship function among position tracking errors and heading tracking error, facilitating the MSV to arrive in the equilibrium point along the pre-designed trajectory. Furthermore, a novel nonsingular and fast terminal sliding mode control (NTSMC) approach is investigated, which ensures faster convergence rate and better stability performance of the close-loop system than the conventional backstepping control approach. What’s more, by incorporating the adaptive technique with the NTSMC approach, an adaptive nonsingular and fast terminal sliding mode control (ANTSMC) strategy is addressed. Compared to the NTSMC approach, it strengthens robustness to disturbances and guarantees system states to converge to a closer neighborhood of the equilibrium point. Finally, simulation results illustrate the remarkable effectiveness of proposed control schemes.

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Background Type 2 diabetes mellitus is common in patients undergoing dialysis. However, the association between anti-diabetic drug use and survival outcomes is rarely discussed. We aimed to investigate whether continued anti-diabetic medication use affects the survival of diabetic dialysis patients and whether different hypoglycemic drug use influences prognosis. Methods Using a nationwide database, we enrolled patients with incident end-stage renal disease under maintenance dialysis during 2011–2015 into the pre-existing diabetes dialysis (PDD), incident diabetes after dialysis (IDD), and non-diabetic dialysis (NDD) groups. The PDD group was further subclassified into patients who continued (PDD-M) and discontinued (PDD-NM) anti-diabetic drug use after dialysis. Results A total of 5249 dialysis patients were examined. The PDD-NM group displayed a significantly higher mortality rate than the IDD, PDD-M, and NDD groups (log-rank test P Conclusions For dialysis patients with diabetes, continuous administration of anti-diabetic drugs after dialysis and choice of medication may affect outcomes.

Introduction: ARDS is often unrecognized. We aimed to developed and validate a deep learning algorithm using EHR structured data to identify patients at risk for ARDS or in-hospital mortality in pre-COVID and COVID-19 inpatient population. Method: The initial cohort consisted of adult ICU patients on mechanical ventilation (MV) from 2017 to 2018 at 3 hospitals at Montefiore Medical Center. Independently trained physician reviewed all chest x-rays in patients with PaO2/FiO2 ratio ≤ 300 to determine ARDS as per Berlin criteria. We used 66 discrete EHR variables to generate 135 features based on variable types. We longitudinally sampled hourly and missing data were forwardly imputed. We trained a preliminary Long Short-Term Memory network to determine the probability of ARDS or in-hospital mortality in the 2017-2018 cohort. Using active learning process, we applied this preliminary model to additional MV patients admitted between 2016-2017 and 2018-2019 to expand the sample size with additional ARDS and non-ARDS patients. The expanded pre-COVID cohort (2016-2019) was split into training and validation cohort (80 and 20%). A new and final LSTM model were trained on the pre-COVID training cohort. Validations were performed on the pre-COVID validation cohort and a population of mechanically ventilated and non-ventilated COVID-19 patients between March-April 2020. Result: The pre-COVID cohort included 3905 MV patients in the ICU from final 2016-2019. 1646 (42.4%) had ARDS and 1033 (26.5%) died during hospitalization. COVID-19 cohort included 5672 patients and 907 (16%) died. 803 (14.2%) were mechanically ventilated including 583 ARDS patients(10.3% of COVID cohort and 72.6% of MV COVID patients) and 418 (52.1%) who died (Table 1). The model ROC was 0.78 for pre-COVID validation cohort. At model cutoff 0.90, the sensitivity was 86% and specificity was 57% (Table 1) In the COVID-19 cohort, the ROC was 0.83 (sensitivity of 70% and specificity of 84%). On the COVID-19 +MV sub-cohort, the model ROC was 0.70 and accurately diagnosed 91.6% of ARDS or death. The model was able to identify ARDS or death close to the time of intubation and ARDS label time in both pre-COVID and COVID-19 cohort (Table 1). Conclusion: Our LSTM algorithm accurately and timely identified the probability ARDS or in-hospital in mechanically ventilated patients. When we applied the model to a larger cohort of hospitalized patients with COVID-19 which had a higher prevalence of ARDS, the sensitivity, and positive predictive value remains high but specificity is much lower among MV patients.

Rationale: Prone positioning is a well-established recruitment maneuver to improve oxygenation and decrease mortality in intubated patients with severe acute respiratory distress syndrome (ARDS). There is evolving literature in utilizing proning among non-intubated and hypoxemic patients with novel coronavirus 2019 (COVID-19). However, there is paucity of evidence proving a sustained improvement in patient-centered outcomes. We aimed to determine the association between prone positioning in non-intubated patients with COVID-19 and incidence of invasive mechanical ventilation (IMV) or in-hospital mortality. Methods: We conducted a nested matched case-control analysis of adult COVID-19 patients admitted to three hospital sites in Bronx, NY between March 1, 2020 and April 1, 2020. Patients with do-not-intubate orders were excluded. Cases were defined by IMV or in-hospital mortality. Each case was matched with two controls based on age, gender, admission date within two weeks, and hospital length of stay greater than index time of matched case via risk-set sampling. Index time was defined as time after hospital admission when the case was intubated or died, whichever came first. The presence of non-intubated proning was identified from provider documentation. Results: We included 600 patients, 41 (6.8%) underwent non-intubated proning. Cases had lower SpO2/FiO2 (S/F) ratios prior to IMV or in-hospital mortality compared to controls (case median, 97 [interquartile range, 90-290] versus control median, 404 [interquartile range, 296-452]). While most providers (58.5%) documented immediate improvement in oxygenation status after initiating non-intubated proning, there was no difference in worst S/F ratios before and after non-intubated proning in both case and control (case median S/F ratio difference, 3 [interquartile range,-3-8] versus control median S/F ratio difference, 0 [interquartile range,-3-50]). In the univariate analysis, patients who underwent non-intubated proning were 2.57 times more likely to require IMV or experience in-hospital mortality (hazard ratio, 2.57;95% confidence interval, 1.17-5.64;P =.02). Following adjustment for patient level differences, we found no association between non-intubated proning and IMV or inhospital mortality (adjusted hazard ratio, 0.92;95% confidence interval, 0.34-2.45;P =.86). Conclusions: Although many providers documented an immediate improvement in oxygenation after non-intubated proning, sustained improvement was not identified. Non-intubated proning did not reduce the need for IMV or in-hospital mortality after adjustment for severity of illness and oxygenation status. While non-intubated proning may temporarily improve hypoxemia, it may lead to harmful delays in intubation and respiratory complications. Physicians should rigorously monitor respiratory parameters when attempting non-intubated proning.

Introduction: Daily spontaneous awakening trials (SAT) have been associated with decreased ventilator and ICU days We evaluated the compliance with SATs in COVID positive patients using electronic health record data and whether increasing SAT performance was associated with mortality, length of stay (LOS) and ventilator-free-days (VFDs). Methods: We retrospectively analyzed mechanically ventilated (MV) COVID positive patients admitted to the ICU from March 10, 2020 to May 21, 2020. Using an EHR-based performance measure for SAT, we excluded patients whom daily SAT was contra-indicated by admission primary ICD-10 codes: status epilepticus, increased intra-cranial pressure, alcoholic withdrawal. Eligibility for SAT for each day on MV was defined as absence of acidosis with pH =0 or had a time period in which no continuous sedating medication were administered. A performance measure for SAT was defined as the percentage of eligible MV days in which SAT was done. Multivariate linear regression was used, adjusting for age, gender, race, and APACHE score and transforming length of stay to satisfy normality assumption. Results: 626 COVID positive patients including 552 on MV were admitted to the ICU during the target time period. Of these, 487 (88%) had at least one ICU day where they met eligibility for SAT. The in-hospital mortality of this cohort was 60.4% (n= 294, Table 1). SAT was performed on 66.7% (IQR 42.9%,100%) of eligible MV days with 5.1% of patients having no SATs done and 34.3% of patients receiving SAT on all eligible days, meaning they reached 100% SAT performance. Multivariate analyses demonstrated that while 100% SAT performance was not significantly associated with mortality (OR 1.06 95% CI (0.71,1.62)), it was associated with shorter hospital LOS and ICU LOS (Hospital LOS coefficient-0.37, 95% CI (-0.51,-0.24) and ICU LOS coefficient-0.74, 95% CI (-0.87,-0.61)) and greater number of ventilator-free days (coefficient 5.36, 95% CI (2.01,8.71)). Conclusion: Improving compliance with SAT on intubated COVID patients may decrease ICU length of stay which has implications for post-COVID recovery as well as resource optimization. We were limited by incomplete documentation during overwhelming COVID surge and likely underpowered to detect significant associations for the primary outcome of in-hospital mortality.

RATIONALE: Preliminary studies have shown varied outcomes when comparing Acute Respiratory Distress Syndrome (ARDS) caused by Coronavirus Disease 2019 (COVID-19) versus “Classic” ARDS. The aim of this study was to compare patient characteristics and outcome of ARDS before and during COVID-19 pandemic. METHODS: We conducted a single center retrospective cohort study at 3 hospitals sites of Montefiore Medical Center comparing a pre-COVID respiratory failure cohort from 2017 to 2018 and a COVID respiratory failure cohort from March 2020 to May 2020. ARDS was identified by having PaO2/FiO2 ratio

Hereditary gingival fibromatosis (HGF) is a rare genetic disorder featured by nonsyndromic pathological overgrowth of gingiva. The excessive gingival tissues can cause dental, masticatory, and phonetic problems, which impose severe functional and esthetic burdens on affected individuals. Due to its high recurrent rate, patients with HGF have to undergo repeated surgical procedures of gingival resection, from childhood to adulthood, which significantly compromises their quality of life. Unraveling the genetic etiology and molecular pathogenesis of HGF not only gains insight into gingival physiology and homeostasis but also opens avenues for developing potential therapeutic strategies for this disorder. Recently, mutations in

This brief is devoted to the predesigned motion trajectory-based finite time dynamic positioning (DP) control for a marine surface vehicle (MSV) with unknown external disturbances. Firstly, a preset motion trajectory is presented through establishing the relationship function among position tracking errors and heading tracking error, facilitating the MSV to arrive in the equilibrium point along the pre-designed trajectory. Furthermore, a novel nonsingular and fast terminal sliding mode control (NTSMC) approach is investigated, which ensures faster convergence rate and better stability performance of the close-loop system than the conventional backstepping control approach. What’s more, by incorporating the adaptive technique with the NTSMC approach, an adaptive nonsingular and fast terminal sliding mode control (ANTSMC) strategy is addressed. Compared to the NTSMC approach, it strengthens robustness to disturbances and guarantees system states to converge to a closer neighborhood of the equilibrium point. Finally, simulation results illustrate the remarkable effectiveness of proposed control schemes.