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In this research, the synthesis of novel derivatives of spiroisatins in high yields was investigated. These new compounds were synthesized using a multicomponent reaction (MCR) of isatin, malononitrile, acetophenone derivatives, diethyl oxalate, primary amines, and Et3N in aqueous media. Under similar conditions, spiropyrroloisatins were prepared using MCRs of synthesized spiroistins. The antioxidant activity of newly synthesized spiroisatins is due to having an NH group which was evaluated by two procedures. Also, the antimicrobial activity of newly generated spiroisatins was evaluated by a disk distribution process utilizing two kinds of Gram‐negative bacteria and Gram‐positive bacteria and bacterial growth was stopped using these compounds. The advantages of this method are short reaction times, high yields of products, and the easy separation of catalyst and product using simple procedures. [ABSTRACT FROM AUTHOR]

Background: Currently, Glasgow Coma Scale (GCS) is used to assess patients' level of consciousness. Although this tool is highly popular in clinical settings, it has various limitations that reduce its applicability in certain situations. This had led researchers to look for alternative scoring systems. This study aims to compare the value of GCS and Full Outline of UnResponsiveness (FOUR) score for prediction of mortality in traumatic brain injury (TBI) patients through a systematic review and meta-analysis. Method: Online databases of Medline, Embase, Scopus, and Web of Science were searched until the end of July 2022 for studies that had compared GCS and FOUR score in TBI patients. Interested outcomes were mortality and unfavorable outcome (mortality + disability). Findings are reported as area under the curve (AUC) sensitivity, specificity, and diagnostic odds ratio. Results: 20 articles (comprised of 2083 patients) were included in this study. AUC of GCS and FOUR score for prediction of in-hospital mortality after TBI was 0.92 (95% CI 0.80–0.91) and 0.91 (95% CI 0.88–0.93) respectively. The diagnostic odds ratio of the two scores for prediction of in-hospital mortality after TBI was 44.51 (95% CI 23.58–84.03) for GCS and 45.16 (95% CI 24.25–84.09) for FOUR score. As for prediction of unfavorable outcome after TBI, AUC of GCS and FOUR score were 0.95 (95% CI 0.93 to 0.97) and 0.93 (95% CI 0.91–0.95), respectively. The diagnostic odds ratios for prediction of unfavorable outcome after TBI were 66.31 (95% CI 35.05–125.45) for GCS and 45.39 (95% CI 23.09–89.23) for FOUR score. Conclusion: Moderate level of evidence showed that the value of GCS and FOUR score in the prediction of in-hospital mortality and unfavorable outcome is comparable. The similar performance of these scores in assessment of TBI patients gives the medical staff the option to use either one of them according to the situation at hand. [ABSTRACT FROM AUTHOR]

Background: Studies show that leaving the hospital with personal consent is increasing. This phenomenon has unpleasant and sometimes irreversible consequences. This study aims to investigate the causes and consequences of leaving the hospital with the personal consent of patients referred to the emergency department of hospitals affiliated with Qom University of Medical Sciences in 2021. Materials and Methods: In this descriptive-analytical study, 345 patients were selected who, with personal consent, left the emergency department of selected hospitals affiliated with Qom University of Medical Sciences in 2021. The study data were collected via a questionnaire and a checklist. The questionnaire comprised demographic variables, patientrelated factors, personnel-related factors, and hospital-related factors. The checklist of the consequences included questions about leaving the hospital with personal consent. The data were analyzed using descriptive and inferential statistics in SPSS software, version 20. Results: Of 345 patients included in the study, 55.9% were male and the mean age of patients was 47.1 years. The most important reasons for leaving the hospital with personal consent were as follows: personal reasons (22.9%), fear of continuing treatment (11.9%), preference to continue the treatment in other medical centers (9.3%), the suggestion of other hospital staff (35.1%), not having the desired doctor (27%), nurses' suggestion (19.4%), lack of care (20.4%), and inadequate hospital space and facilities (14.0%). The consequences of leaving the hospital with personal consent in this study included re-admission and hospitalization (10.3%), mortality (3.4%), heart disease (0.87%), and mental disorders (0.57%). Conclusion: After identifying the reasons for leaving the hospital with personal consent and highlighting the irreparable human and financial consequences, these causes should be eliminated to prevent irreparable and unfortunate consequences. Such causes include personal reasons, fear of continuing the treatment, and lack of care. Fixing the causes requires proper planning and effective actions. [ABSTRACT FROM AUTHOR]

Outlier detection has been widely explored and applied to different real-world problems. However, outlier characterization that consists in finding and understanding the outlying aspects of the anomalous observations is still challenging. In this paper, we present a new approach to simultaneously detect subspace outliers and characterize them. We introduce the Dimension-wise Local Outlier Factor (DLOF) function to quantify the degree of outlierness of the data points in each feature dimension. The obtained DLOFs are used in an outlier ensemble so as to detect and rank the anomalous points. Subsequently, the same DLOFs are analyzed in order to characterize the detected outliers with their relevant subspace and their same-type anomalies. Experiments on various datasets show the efficacy of our method. Indeed, we demonstrate through an experimental evaluation that the proposed approach is competitive compared to the existing solutions in terms of both detection and characterization accuracy. [ABSTRACT FROM AUTHOR]

Ensuring service continuity in safety critical applications is crucial. In some of these applications, multilevel converters play a vital role. In this regard, this research work presents a self-healing fault-tolerant control approach to ensure the resiliency of a neutral-point clamped converter when a semiconductor component encounters an open circuit fault. The defective semiconductor can be a power switch or a clamping diode. By applying the proposed real-time fault-tolerance control, the rated output voltage and output current are restored during post-fault operation. Furthermore, the total harmonic distortion value of the output voltage during application of the real time self-healing control does not increase when compared with that during healthy operation. Since the realization of the proposed control strategy does not require any bidirectional switch, a fast transition between the healthy and fault-tolerant operation is accomplished. Moreover, the proposed structure can ensure service continuity in case of a fault event in the anti-parallel diodes, something which has been overlooked in previously conducted research works. [ABSTRACT FROM AUTHOR]

Background: Patient engagement in patient safety is aimed at increasing the awareness and participation of patients in error-prevention strategies. The aim of this project was to improve the patient safety with the patient engagement within the local context of a maternity hospital by implementing best practice. Methods: A clinical audit was conducted using the JBI Practical Application of Clinical Evidence System tool. The current project was conducted in surgical ward of Shahid-Beheshti maternity hospital, Iran. The sample size was 46 patients and 46 healthcare practitioners for both the baseline and follow-up. In phase 1, four audit criteria were used and a baseline audit was conducted for this project. In phase 2, barriers to compliance were identified, and strategies were adopted to promote best practice. In phase 3, a follow-up audit was conducted. Results: The results showed varying levels of compliance with the four criteria used in this project. The criterion 1, which was related to training of healthcare practitioners on how they can support patients, has the highest compliance at 87% in baseline and follow up data collection. Furthermore, compared with the baseline data (criterion 2 = 52%; criterion 3 = 37%; criterion 4 = 61%), compliance with criteria 2, 3, and 4 notably improved at 85, 76, and 92%, respectively. Conclusions: The present project successfully implements patient engagement in Iran and reveals varying results on compliance and the increasing knowledge of healthcare practitioners and patients on evidence-based patient engagement in order to improve the patient safety. The used strategies can facilitate implementation of evidence based procedures in clinical practice. [ABSTRACT FROM AUTHOR]

Multilevel inverters are increasingly used in industrial applications in which service continuity is crucial. This paper presents an original approach to ensure the fault-tolerant operation of neutral-point-clamped (NPC) inverters in the case of an open-circuit fault event in a clamping diode, which is rarely investigated in the conducted research work. The proposed fault-tolerant strategy meets the following criteria: restoring rated output voltage and current during post-fault operation, realizing fault-tolerant operation without additional components, maintaining rated total harmonic distortion (THD) during fault-tolerant operation, and fast transition between faulty operation and remedial operation. In the proposed approach, prior to applying the appropriate remedial action, identification of the defective clamping diode is required. In this respect, a very fast and simple logic-based fault diagnosis is presented whose implementation does not need any additional components and external circuit. Moreover, it does not require any component modeling and complicated calculations. The proposed strategy is validated by simulation and experimentation. [ABSTRACT FROM AUTHOR]

The fault diagnosis in multilevel converters is of great importance since they are comprised of more solid-state switches, compared with the conventional two-level converters. In this article, we propose a fast and efficient real-time fault detection and faulty component identification for an open-switch fault diagnosis based on the failure-mode algorithm for a single-phase five-level neutral-point-clamped inverter. Component modeling, complicated calculations, and load parameters are not required for realizing the proposed approach. Furthermore, the proposed strategy does not require any extra sensors. The signals already available in the control system, such as the applied switching pattern and terminal voltage, fulfill the fault diagnosis. Thanks to the proposed fault detection strategy, any misdiagnosis arising from noise existence, response time of the sensors, turn on and turn off delay times of the power switches, and measurement errors are avoided. The simulations and experiments are carried out to confirm the performance and effectiveness of the presented strategy. [ABSTRACT FROM AUTHOR]

Context: In some studies, Fresh Frozen Plasma (FFP) transfusion in severely ill patients was accompanied with an increase in the risk of nosocomial infection. However, there are no comprehensive data in terms of FFP transfusion and its relationship with nosocomial infection in heart surgery. Hence, the present systematic review and meta-analysis aimed to investigate the relationship between FFP transfusion and nosocomial infection risk in the patients undergoing cardiac surgery. Evidence Acquisition: Study selection: The present study included all the studies, which probed into nosocomial infection after FFP transfusion in patients with cardiac surgery. Data sources: Medline, Web of Science, Embase, Central, and Scopus electronic databases were searched to the end of March 2019. Results: Finally, five articles and three abstracts that studied nosocomial infection were entered into the present systematic review. FFP increased the rate of nosocomial infection in cardiac surgery in one article, but this was not the case in the remaining four articles. The three abstracts also reported that FFP increased the rate of nosocomial infection in cardiac surgery. Conclusion: The studies indicated that the benefit of FFP administration outweighed the probable risk of infection. Indeed, none of the studies indicated a strong relationship between FFP transfusion and infection rate after cardiac surgery. [ABSTRACT FROM AUTHOR]

Hiccups that last more than 48 hours are known as persistent hiccups. A 38-year-old man presented to the emergency with a 3-day history of persistent hiccups, and after partial treatment and normal test results, he was discharged from the emergency. After 22 hrs, he was brought to the emergency again with a complaint of stuttering and was admitted with a chance of stroke. A 50% stenosis development in the right carotid artery was reported, and the MRI results were normal. After 20 hrs of admission, the patient's stutter was thoroughly treated, and he was discharged with the diagnosis of TIA. Persistent hiccups can be a precursor to a stroke. [ABSTRACT FROM AUTHOR]

In this paper, a five-level neutral-point-clamped (NPC) inverter with short-circuit fault-tolerant capability is presented. Based on the proposed approach, in order to ensure service continuity subsequent to a short-circuit fault event in a switch, two steps are carried out. First of all, destructive consequences arising from short-circuit fault in a power switch is prevented. Afterwards, according to the defected component, remedial actions are taken. The proposed strategy does not require any redundant component. The service continuity is acquired by applying a remedial control and modifying switching commands applied to the power switches. Using the proposed approach helps to restore the rated voltage and rated current at the terminal, and there is no limit for modulation index during fault-tolerant operation under remedial control. Furthermore, compared to healthy operation, harmonic content of the terminal voltage and current is not deteriorated during fault-tolerant operation. Moreover, additional components, such as bidirectional switches and contactors, are not employed in this strategy. Only some fast fuses are placed in the converter circuit for protection purposes which do not impose a noticeable cost compared to the bidirectional switches and contactors. [ABSTRACT FROM AUTHOR]

Network anomaly detection systems (NADSs) play a significant role in every network defense system as they detect and prevent malicious activities. Therefore, this paper offers an exhaustive overview of different aspects of anomaly-based network intrusion detection systems (NIDSs). Additionally, contemporary malicious activities in network systems and the important properties of intrusion detection systems are discussed as well. The present survey explains important phases of NADSs, such as pre-processing, feature extraction and malicious behavior detection and recognition. In addition, with regard to the detection and recognition phase, recent machine learning approaches including supervised, unsupervised, new deep and ensemble learning techniques have been comprehensively discussed; moreover, some details about currently available benchmark datasets for training and evaluating machine learning techniques are provided by the researchers. In the end, potential challenges together with some future directions for machine learning-based NADSs are specified. [ABSTRACT FROM AUTHOR]

This paper presents a multi-objective optimal rotor design for an interior permanent magnet synchronous motor (IPMSM) based on finite element analysis. Due to the importance of torque characteristic in electromagnetic design of IPMSMs, the main efforts of this study are focused on finding a proper trade-off for its torque profile challenges. In this regard, in order to attain high average torque and low torque ripple, the influence of several key factors, such as the permanent magnet (PM) arrangements, PM positions and PM sizes, are examined. Subsequently, according to the outcomes of the performed sensitivity analysis, the appropriate variation interval of the parameters as well as their initial values is determined. Employing such a deterministic optimization algorithm, which does not need large sample points, minimizes the finite element computational cost and leads to accelerate the convergence process. The two-dimensional finite element model (FEM) of an IPMSM is used to perform a sensitivity analysis and establish a multi-objective FEM-based optimization. [ABSTRACT FROM AUTHOR]