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BackgroundMethodsResultsConclusionWith the increasing cases of TBI cases in the elderly population taking anticoagulants for comorbidities, there is a need to better understand the safety of new anticoagulants and how to manage anticoagulated TBI patients.A meta-analysis using a random-effect model was conducted to compare the effect of preinjury use of DOACs and VKAs on the outcomes following TBI.From 1951 studies, 49 studies with a total sample size of 15,180 met our inclusion criteria. Our meta-analysis showed no difference between preinjury use of DOACs or VKAs on ICH progression, in-hospital delayed ICH, delayed ICH at follow-up, and in-hospital mortality, but using DOACs was associated with a lower risk of immediate ICH (OR = 0.58; 95% CI = [0.42; 0.79]; p < 0.01) and neurosurgical interventions (OR = 0.59; 95% CI = [0.42; 0.82]; p < 0.01) compared to VKAs. Moreover, patients on DOACs experienced shorter length of stay in the hospital than those on VKAs (OR = -0.42; 95% CI = [−0.78; −0.07]; p = 0.02).We found a lower risk of immediate ICH and surgical interventions as well as a shorter hospital stay in patients receiving DOACs compared to VKA users before the head injury. [ABSTRACT FROM AUTHOR]

This paper presents a novel topology for Z-source inverters (ZSI). The new Z-Source network is based on the coupled-inductors and active switched boost. Features of the topology include high voltage boost ability, single magnetic-core, low voltage stress on the active switch, and capacitors. The principles of operation, analysis, voltage and current equations of each component, and the converter voltage gain in the steady-state are presented. A comparison with other topologies has also been performed to determine the advantages and disadvantages of the proposed ZSI. Finally, experimental results of the laboratory prototype are presented to confirm the performance of the proposed topology. [ABSTRACT FROM AUTHOR]

In this paper, an interleaved DC–DC step-up converter with improved characteristics based on a voltage multiplier rectifier is presented. The proposed converter is presented and analyzed for two different operating duty regions including operating region 1 (0 < D ≤ 0.5), and operating region 2 (0.5 ≤ D < 1). This converter can be used in various applications such as energy storage, electric vehicles, and renewable energy systems. This converter is composed of two stages: an interleaved boost stage and a voltage multiplier rectifier stage, which collectively forms its general structure. The interleaved boost stage is a type of two-phase boost converter that transforms the input DC voltage into a high-frequency AC square waveform. This waveform can be readily filtered using smaller capacitors. The square-shaped voltage waveform from the interleaved boost stage is rectified and converted to a high DC voltage by the Voltage Multiplier Rectifier (VMR) stage. The operating regions, the evaluation of the steady-state condition, the voltage gain of the proposed converter's parasitic and ideal models as well as its losses and efficiency analysis have been evaluated. The proposed converter has an efficiency of 97% at the output power of 150 W. The proposed converter is simulated to convert a voltage of 25–159.5 V and to validate the mathematical relationships and simulation results, a laboratory prototype has been developed. The simulation and experimental results show the precision of the performance of the proposed interleaved boost converter. [ABSTRACT FROM AUTHOR]

Summary Multilevel inverters are known as essential converters in renewable sources. First, in this paper, a new submodule is presented, and based on it, a new sub‐multilevel inverter is presented. The proposed sub‐multilevel inverter consists of several unidirectional and bidirectional switches and DC voltage sources. Then, the generalized topology, developed in two modular and cascaded modes, is presented to increase production levels. The proposed submodules are connected in series in the modular topology, increasing production levels. The proposed topology to produce the maximum output levels has the minimum number of IGBTs, drivers, DC voltage sources, etc. Mathematical analyses for conduction and switching losses are provided, and mathematical analyses for the number of devices and voltage across the switches are also presented. In addition to the mathematical analysis of losses, the simulation results are also presented. A general comparison of proposed topology components is presented to demonstrate their advantages. This comparison shows that the proposed topology has the minimum number of power electronic devices. In this paper, nearest level modulation is used to control the proposed topology. The simulation and experimental results of the proposed sub‐multilevel verify the performance of the proposed topology. [ABSTRACT FROM AUTHOR]

This paper presents a non‐isolated single‐switch ultra‐high step‐up (UHSU) DC–DC converter with a three‐winding coupled inductor (CI) which is utilized to achieve ultra‐high voltage gain with a small amount of duty cycle leading to low conduction losses of the power switch and higher efficiency. The voltage gain of the suggested UHSU converter is adjusted by two methods: the duty cycle of the power switch and the three‐winding CI turn ratio, therefore enhancing the design flexibility of the suggested converter. Due to the utilization of the passive clamp circuit in the structure of the proposed converter, it is possible to select a power switch with low voltage rated and small ON‐state resistance, further enhancing the converter efficiency. The operation modes are discussed in detail and to clarify the salient features of the proposed converter, a comparison with other configurations is provided. Finally, to accredit the performance of the proposed converter, a 150‐W laboratory archetype with an input and output voltage of 20 and 300 V, respectively, at 50 kHz switching frequency is fabricated. [ABSTRACT FROM AUTHOR]

Background: Traumatic brain injury (TBI) is a leading cause of death and disability worldwide. It has been estimated that 64-74 million individuals experience TBI from all causes each year. Due to these variations in reporting TBI prevalence in the general population, we decided to perform a meta-analysis of published studies to better understand the prevalence of TBI in the general adult population of the US which can help health decision-makers in determining general policies to reduce TBI cases and their costs and burden on the healthcare system., Methods: Our meta-analysis was performed using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) checklist. The study protocol was registered with PROSPERO (CRD42024534598). A comprehensive literature search of PubMed from the National Library of Medicine and Google Scholar was performed from database inception to April 2024. Sixteen studies that evaluated the US general population met our inclusion criteria. A meta-analysis using a random-effects model was performed to estimate the prevalence of TBI in the general adult population of the US., Results: The total sample consisted of 27,491 individuals, of whom 4,453 reported a lifetime history of TBI with LOC (18.2%, 95% CI 14.4-22.7%). Some studies did not report relevant information based on gender, but based on available data, among males, 1,843 individuals out of 8,854 reported a lifetime history of TBI with LOC (20.8%). Among females, 1,363 individuals out of 11,943 reported a lifetime history of TBI with LOC (11.4%). The odds of sustaining TBI in males was higher than in females with moderate heterogeneity between studies (OR = 2.09, 95% CI 1.85-2.36, p &lt; 0.01, I2 = 40%)., Conclusion: The prevalence of TBI in the US general population is 18.2%, making it a major public health concern. In addition, males were more than twice as likely as females to sustain TBI with LOC. Considering the irreparable long-term adverse effects of TBI on survivors, their families, and the healthcare system, prevention strategies can facilitate substantial reductions in TBI-related permanent disabilities and medical care costs., (S. Karger AG, Basel.)