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Abstract The multiphase matrix converter outperforms the conventional three‐phase system with higher fault tolerance capability and higher power control competency. This paper discusses the direct control based on different possible switching combinations of a three‐phase to five‐phase matrix converter (MC). The proposed control topology significantly reduces the switching commutations in a switching cycle when compared with its counterpart. The control is based on the modified space vector pulse width modulation (SVPWM) strategy. The proposed space vector scheme intelligently selects the voltage vectors to get the desired output characteristics with the least possible switching transitions in a switching cycle. Three possible cases exist in controlling space vectors based on their magnitude, the number of active switching vectors, and their commutations. The results for three different cases of SVPWM have been presented and compared. The total harmonic distortion (THD) obtained in the output is lower in case 2; however, it suffers from a higher common‐mode voltage (CMV). The scheme has been successfully implemented and verified in hardware.

Key Clinical Message We present an interesting case that showed a non‐hematopoietic structure embedded in the bone marrow biopsy. Given the clinical and morphological difficulties, it was challenging to identify this artifact's nature. Publishing this case would familiarize pathologists with this artifact and save additional testing and delays in reporting.

Introduction Nontraumatic Intracerebral Hemorrhage (ICH) is the second most prevalent type of stroke worldwide and is strongly linked with severe disability and mortality. Survivors of ICH have a high risk of all‐cause readmission. Understanding characteristics of readmitted patients and etiologies of readmission may provide a framework for risk stratification and readmission prevention. Methods We identified patients with a primary diagnosis of ICH (ICD‐10 code: I61.x) from 2016‐2019 using the Nationwide Readmission Database (NRD). The difference in days between the index admission and the readmission was used to identify patients who were readmitted within 30 and 90 days. The primary diagnosis of the readmission was used to identify the etiology of readmission. Data was weighted to allow for representative nationwide estimates. Results A total of 260,854 patients were admitted with a primary diagnosis of ICH between 2016‐2019. The mean age of the cohort was 68.49 years, with 52.6% being male. The 30‐day readmission rate was 7.68% while the 90‐day readmission rate was 12.73%. There was a small but significant increase in 90‐day readmission rates from 2016 to 2019 (12.61% vs 12.93%, p=0.05), but no significant increase in 30‐day readmission rates (7.10% vs 7.72%, p=0.870). Around 60% of 90‐day readmissions occurred within the first 30 days. Patients readmitted within 30 days and within 90 days, compared to those not requiring readmission, were more likely to be younger (68 and 68.1 vs 68.53 years) and male (54.87% and 53.92% vs 52.41) (p

Introduction Subarachnoid Hemorrhage (SAH) is the leading cause of morbidity and mortality in stroke patients, associated with severe neurological, infectious, and thromboembolic complications. Identifying clinical predictors linked to hospital readmissions after a SAH allows for the determination of patients with higher risks of complications, opening an avenue for prevention and improved quality of care. Methods The Nationwide Readmission Database (NRD) was used to extract patients with SAH (ICD‐10 code: I60.x) from 2016‐2019. The difference in days between the index admission and the readmission was used to identify patients who were readmitted within 30 and 90 days. The primary diagnosis of the readmission was used to identify the etiology of readmission. Data was weighted to allow for representative nationwide estimates. Results We identified 68,726 patients with SAH, with a mean age of 60.47 years, and 57.86% being female. Overall, 7.79% (n=5354) were readmitted within 30 days and 12.04% (n=8525) were readmitted within 90 days. The rate of 30‐day readmission was overall stable (7.34% in 2016 and 7.70% in 2019; p=0.42), but the 90‐day readmission rate slightly increased from 11.69% in 2016 to 12.47% in 2019 (p=0.04). Around 62% of 90‐day readmissions occurred within the first 30 days. Patients readmitted within 30 days were more likely to be older (mean age = 61.92 vs 60.99 years; p

Introduction Primary Angiitis of the Central Nervous System (PACNS) is a rare, relapsing inflammatory disorder of blood vessels in the brain and spinal cord presenting clinically with a spectrum of manifestations including strokes, seizures, and neurologic deficits. Limited data are available on the modifiable and nonmodifiable predictors of readmissions for patients diagnosed with PACNS, which hinders the ability of healthcare systems to risk‐stratify patients based on their specific demographics, comorbidities, and hospital status. Methods We identified patients with PACNS (ICD‐10 code: I67.7) admitted from 2016‐2019 using the Nationwide Readmission Database (NRD). The difference in days between the index admission and the readmission was used to identify patients who were readmitted within 30 and 90 days. The primary diagnosis of the readmission was used to identify the etiology of readmission. Data was weighted to allow for representative nationwide estimates. Results We identified 1,398 patients admitted with a primary diagnosis of PACNS between 2016 and 2019. The mean age was 52.81 years, with 59.20% (n=828) being female. The 30‐day readmission rate was 10.52% (n=147) and the 90‐day readmission rate was 19.60% (n=274). Nearly half of 90‐day readmissions occurred within the first 30 days. Annual variations in readmission rates were insignificant. Age and sex distribution were not statistically different between patients not requiring readmission, those readmitted within 30 days, and those readmitted within 90 days. Compared to those not requiring readmission, patients readmitted within 30 days had a higher prevalence of diabetes (38.07% vs 29.06%; p=0.023) and hypertension (65.66% vs 56.88%; p=0.035), while those readmitted within 90 days had a higher prevalence of diabetes (41.56% vs 27.19%, p

Introduction Transient Ischemic Attack (TIA) is a common neurologic condition characterized by temporary, focal cerebral ischemia that results in reversible neurological deficits without tissue infarction. Type 2 Diabetes Mellitus (T2DM) is a rapidly growing global health problem with increasing prevalence. Currently, data are lacking regarding the trends of 90‐day readmission rates and etiologies among diabetic patients with TIA. Methods We used the Nationwide Readmission Database (NRD) to identify patients with a primary diagnosis of TIA (ICD‐10 code: G45.9) from 2016‐2019 and secondary diagnosis of T2DM. The difference in days between the index admission and the readmission was used to identify patients who were readmitted within 90 days. The primary diagnosis of the readmission was used to identify the etiology of readmission. Data was weighted to allow for representative nationwide estimates. Results We identified 426,549 patients who were admitted with a primary diagnosis of TIA between 2016 and 2019. Of those patients, 35.43% (n=273,993) were diabetic and 64.57% (n=151,112) were non‐diabetic. Diabetics were more likely to be younger (70.43 vs 70.71 years, p

Background Traumatic direct carotid cavernous fistulas results in a direct communication between the internal carotid artery and the cavernous sinus. Covered stents are not frequently used in neuro‐endovascular procedures due to concerns primarily about occlusion of perforating vessels. There are however several factors in direct carotid cavernous fistulas that make it more amenable to covered stenting than other diseases treated endovascularly. Methods Wepresent 2 cases of occlusion of traumatic direct carotid cavernous fistulas utilizing the PK Papyrus stent. Results In our first case, this device was successfully used as a salvage technique afterfailure of conventional techniques and in the second case it was used as primary treatment. Conclusion The properties of the PK Papyrus covered stent are promising in overcoming the difficulties of other covered stents and warrants further investigation.

Abstract Spinal tuberculosis (TB) is diagnostically challenging, particularly in atypical forms. Non‐contiguous multilevel spinal TB (NMLST) is a rare presentation of spinal TB, mimicking spinal malignancies. We reported an unusual NMLST case with a paraspinal and epidural abscess in a young patient with misleading clinical and imaging presentations.

Abstract Technology‐driven control measures could be an important tool to control the COVID‐19 pandemic crisis. This study evaluates the potentiality of emerging technologies such as 5G and 6G communication, Deep Learning (DL), big data, Internet of Things (IoT) etc. for controlling the COVID‐19 transmission and ensuring health safety. The healthcare sector is able to provide a unified, rapid, and incessant service to people by applying modern wireless connectivity tools like 5G or 6G during the COVID‐19 pandemic. This study has identified eight key areas of applications for the COVID‐19 management like infection detection; travel history analysis; identification of infection symptoms; early detection; transmission identification; access to information in lockdown; movement of people; and development of medical treatments and vaccines. Data have been collected from the respondents living in Sakaka city, KSA during pandemic. This study reveals that most people receive information from social networking sites, health professionals, and television without facing any challenges. The analysis shows that, during the COVID‐19 pandemic, about 42% of respondents felt tense always or most of the time in a day. Only 28.6% of respondents felt tense sometimes, whereas the remainder (about 30%) did not feel tense in relation to the COVID‐19 crisis. Satisfaction with COVID‐19‐related information is also positively correlated with COVID‐19‐related information literacy (r = 0.53, p

Abstract Nanoneedles can target nucleic acid transfection to primary cells at tissue interfaces with high efficiency and minimal perturbation. The corneal endothelium is an ideal target for nanoneedle‐mediated RNA interference therapy aimed at enhancing its proliferative capacity, necessary for tissue regeneration. This work develops a strategy for siRNA nanoninjection to the human corneal endothelium. Nanoneedles can deliver p16‐targeting siRNA to primary human corneal endothelial cells in vitro without toxicity. The nanoinjection of siRNA induces p16 silencing and increases cell proliferation, as monitored by ki67 expression. Furthermore, siRNA nanoinjection targeting the human corneal endothelium is nontoxic ex vivo, and silences p16 in transfected cells. These data indicate that nanoinjection can support targeted RNA interference therapy for the treatment of endothelial corneal dysfunction.

Abstract A new fault diagnosis method for detecting the rotor eccentricity faults including static, dynamic and mixed eccentricity is proposed for brushless doubly‐fed induction machines (BDFIMs). BDFIMs are attractive alternatives for the conventional doubly‐fed induction generator (DFIG) for offshore wind power generation; therefore, paying attention to their fault detection is essential. Existing fault detection methods for conventional induction machines cannot be directly applied to the BDFIM due to its special rotor structure and stator winding configurations as well as complex magnetic field patterns. This article proposes a novel fault detection method based on motor current signal analysis to determine stator current harmonics, induced by the nested‐loop rotor slot harmonics (NRSHs), as fault indices. The analysis is performed under healthy conditions and with different types of rotor eccentricity. Finally, a sensitivity analysis is carried out to confirm the practicability of the proposed technique with various fault intensities and load conditions. Analytical winding function approach, finite element analysis and experimental tests on a prototype D180 BDFIM are used in this study to validate the proposed fault detection technique.

Abstract The present study was designed to develop a disease predictive model based upon meteorological variables, that is, minimum and maximum temperatures, rainfall, and relative humidity to predict lentil wilt severity. Correlation and regression analyses were performed to determine the relationship of meteorological variables with disease severity. A significant correlation was found between all meteorological variables and lentil wilt severity. Maximum temperature showed negative correlation, while minimum temperature, rainfall, and relative humidity exhibited positive correlation with lentil wilt severity. Environmental variables and disease severity data of 2 years (2017–2018) were used to develop a disease predictive model using a stepwise multiple regression analysis. Maximum and minimum temperatures, rainfall, and relative humidity significantly contributed to disease development and explained 94.39% variability in disease severity. This model, based on 2 years data, was then validated with 5 years (2012–2016) meteorological variables and disease severity data set. Homogeneity of regression line in the multiple regression equations of 2 years (2017–2018) model and 5 years (2012–2016) model indicated that they validated each other. Lentil wilt severity was high at maximum (17–25°C) and minimum temperature (9.5–15.1°C), rainfall (4.5–6.5 mm), and relative humidity (55%–85%), respectively. The lentil wilt disease predictive model developed for four lentil varieties, namely M‐85, NL‐2, Mansehra‐89, and NARC‐08‐1, during the present investigation will be useful to predict disease severity before epidemic occurrence and the time of fungicide application. Hence, the model is helpful to reduce the use of fungicides, lessen environmental pollution, and help limit the cost of production of lentil growers.

Abstract Oligodendrogliomas (ODGs) are rare brain tumors in adults, mostly presenting as a supratentorial solid mass, while less than 10% occur infratentorially. Infratentorial cystic ODGs are extremely rare. We reported a large partially cystic cerebellar ODG in a 31‐week pregnant patient with an unusual presentation and discussed the challenging management.

This study studies, using experimentally verified finite element (FE) analysis, various performance measures of the brushless doubly fed induction generator (BDFIG) when magnetic wedges are used for closing stator open slots. The BDFIG is an attractive generator solution for offshore wind power and can replace doubly fed slip-ring induction generators. It is shown in this study that the use of magnetic wedges, commonly used in large induction machines, reduces the stator windings magnetising currents in a BDFIG, reflected in the values of magnetising inductances. They also increase the leakage flux in the stator slots, leading to a larger series inductance in the equivalent circuit. The series inductance significantly affects the BDFIG performance as well as the rating of its converter. The effects of magnetic wedges on BDFIG air-gap flux, synchronous torque, and stator tooth top saturation is also investigated. Two-dimensional FE analysis of an experimental 250 kW BDFIG is used in this study, verified by experimental measurements.

In this study, a novel 6-degree of freedom compact carrier using magnetically levitated transverse flux permanent magnet linear synchronous motor is proposed and initial design characteristics are analysed. Motor structure is compact with magnetic iron cores for thrust and levitation, arranged orthogonally. This allows reduced magnetic coupling between linear synchronous motor (LSM) and electromagnets despite their close proximity. Such configuration also ensures independent design for propulsion and suspension. Furthermore, by virtue of the proposed configuration, yaw and lateral motion are inherently stable, leaving the required active actuators to merely four for thrust, pitch, roll, and heave active control. Preliminary characteristics are analysed using 3D finite element method and performance considerations for the simultaneous design of LSM and electromagnets are discussed thoroughly.