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This work proposes a novel technique for transmission of data from two different sources by using a combination of wavelength shift keying (WSK) and pulse position modulation (PPM) over a free space optical (FSO) link. It has been shown that the proposed technique has potential of improving the physical layer security of FSO links, which is a growing concern due to considerable interest in the employment of FSO for high data rate applications. The proposed technique transmits at a combined data rate of 20 Gbps over a single pulse per bit slot. The wavelength and position in time of the pulse is varied according to the combination of bits received from the two different data sources. Gamma–Gamma channel model is used to simulate the FSO link whose length has been varied from 0.5 km to 3 km to observe the bit error rate (BER) performance. The BER has also been observed for different time delays induced over the optical pulse for implementing the PPM technique. It has been shown that the proposed technique can work under different time delays, hence making it difficult for an eavesdropper to sample the optical pulses at the correct instant for information extraction. Furthermore, this scheme allows us to perform balanced detection, resulting in wider eye opening at the receiver.

PURPOSE To investigate the differences in the visibility and size of abdominal wall hernias in computed tomography (CT) with and without Valsalva maneuver. METHODS This single-center retrospective study included consecutive patients who underwent abdominal CTs with Valsalva maneuver between January 2018 and January 2022. Inclusion criteria was availability of an additional non-Valsalva CT within 6 months. A combined reference standard including clinical and surgical findings was used. Two independent, blinded radiologists measured the hernia sac size and rated hernia visibility on CTs with and without Valsalva. Differences were tested with a Wilcoxon signed rank test and McNemar's test. RESULTS The final population included 95 patients (16 women; mean age 46 ± 11.6 years) with 205 hernias. Median hernia sac size on Valsalva CT was 31 mm compared with 24 mm on non-Valsalva CT (p < 0.001). In 73 and 82% of cases, the hernias were better visible on CT with Valsalva as compared to that without. 14 and 17% of hernias were only visible on the Valsalva CT. Hernia visibility on non-Valsalva CT varied according to subtype, with only 0 and 3% of umbilical hernias not being visible compared with 43% of femoral hernias. CONCLUSIONS Abdominal wall hernias are larger and better visible on Valsalva CT compared with non-Valsalva CT in a significant proportion of patients and some hernias are only visible on the Valsalva CT. Therefore, this method should be preferred for the evaluation of abdominal wall hernias.

This paper comprehensively reviews several techniques that address the static and dynamic voltage balancing of series-connected MOSFETs. The effectiveness of these techniques was validated through simulations and experiments. Dynamic voltage-balancing techniques include gate signal delay adjustment methods, passive snubbers, passive clamping circuits, and hybrid solutions. Based on the experimental results, the advantages and disadvantages of each technique are investigated. Combining the gate-balancing core method with an RC snubber, which has proven both technically and commercially attractive, provides a robust solution. If the components are sorted and binned, voltage-balancing techniques may not be necessary, further enhancing the commercial viability of series-connected MOSFETs. An investigation of gate driver topologies yields one crucial conclusion: magnetically isolated gate drivers offer a simple and cost-effective solution for high-frequency (HF) applications (2.5–50 kHz) above 8 kV with an increased number of series devices. Below 8 kV, it is advantageous to move the isolation barrier from the gate drive IC to an optocoupler and isolated supply, allowing for a simple design with commercially available components., High Voltage Technology Group

INTRODUCTION Compression syndromes of the celiac artery (CAS) or superior mesenteric artery (SMAS) are rare conditions that are difficult to diagnose; optimal treatment remains complex, and symptoms often persist after surgery. We aim to review the literature on surgical treatment and postoperative outcome in CAS and SMAS syndrome. METHODS A systematic literature review of medical literature databases on the surgical treatment of CAS and SMAS syndrome was performed from 2000 to 2022. Articles were included according to PROSPERO guidelines. The primary endpoint was the failure-to-treat rate, defined as persistence of symptoms at first follow-up. RESULTS Twenty-three studies on CAS (n = 548) and 11 on SMAS (n = 168) undergoing surgery were included. Failure-to-treat rate was 28% for CAS and 21% for SMAS. Intraoperative blood loss was 95 ml (0-217) and 31 ml (21-50), respectively, and conversion rate was 4% in CAS patients and 0% for SMAS. Major postoperative morbidity was 2% for each group, and mortality was described in 0% of CAS and 0.4% of SMAS patients. Median length of stay was 3 days (1-12) for CAS and 5 days (1-10) for SMAS patients. Consequently, 47% of CAS and 5% of SMAS patients underwent subsequent interventions for persisting symptoms. CONCLUSION Failure of surgical treatment was observed in up to every forth patient with a high rate of subsequent interventions. A thorough preoperative work-up with a careful patient selection is of paramount importance. Nevertheless, the surgical procedure was associated with a beneficial risk profile and can be performed minimally invasive.

Use of extracorporeal membrane oxygenation (ECMO) in children receiving haematopoietic cell transplantation (HCT) and immune effector cell therapy is controversial and evidence-based guidelines have not been established. Remarkable advancements in HCT and immune effector cell therapies have changed expectations around reversibility of organ dysfunction and survival for affected patients. Herein, members of the Extracorporeal Life Support Organization (ELSO), Pediatric Acute Lung Injury and Sepsis Investigators (PALISI) Network (HCT and cancer immunotherapy subgroup), the Pediatric Diseases Working Party of the European Society for Blood and Marrow Transplantation (EBMT), the supportive care committee of the Pediatric Transplantation and Cellular Therapy Consortium (PTCTC), and the Pediatric Intensive Care Oncology Kids in Europe Research (POKER) group of the European Society of Pediatric and Neonatal Intensive Care (ESPNIC) provide consensus recommendations on the use of ECMO in children receiving HCT and immune effector cell therapy. These are the first international, multidisciplinary consensus-based recommendations on the use of ECMO in this patient population. This Review provides a clinical decision support tool for paediatric haematologists, oncologists, and critical care physicians during the difficult decision-making process of ECMO candidacy and management. These recommendations can represent a base for future research studies focused on ECMO selection criteria and bedside management.

We report the synthesis of titania nanofibers (TNF) of ?195 nm mean diameter doped with phosphorus through one-pot electrospinning followed by decoration of Ag nanoparticles (NPs). The Ag NPs of ?8 nm size on 2 % P-doped TNFs (Ag-PTNFs) showed excellent photocatalytic activity for the reduction of Cr(VI), under simulated solar light, with ?100 % conversion to Cr(III) in 90 min at pH 3 with a pseudo-first order rate constant of 0.085 min?1 that is 96.5 % higher than TNFs. The Ag-PTNFs also exhibited excellent photodegradation of methylene blue with pseudo-first order rate constant of 0.052 min?1 which is 82.7 % better than TNFs. The enhanced photocatalytic performance of Ag-PTNFs is attributed to the reduced band-gap, increased charge separation and reduced recombination rates. A proposed photocatalytic mechanism based on the synergistic effect of both Ag and P doping is presented which highlights the potential of these composite materials for water remediation. © 2020 Wiley-VCH GmbH

Carbon-based supercapacitive materials are promising energy storage materials because of their high power density and long durability. The energy density of carbon based materials can be significantly improved by making their hybrids with metal/metal oxides and hydroxides. Here, we successfully fabricated the electrospun carbon nanofibers (CNFs) with Fe encapsulated carbon nanotubes (CNTs) by simple chemical vapor deposition (CVD). The Fe nanoparticles later got oxidized by absorbing oxygen from air resulting in the desired hierarchical Fe/Fe3O4 encapsulated CNT/CNF nanostructure (Fe/Fe3O4@CNT-CNF). The composite material showed a high specific capacitance of 195 F g-1 at 0.5 A g-1, areal capacitance of 398 m F cm-2 in 1 M KOH and long term durability with 95% capacitance retention even after 5000 charge discharge cycles. The findings of our results suggest that Fe/Fe3O4@CNT-CNF hybrid is a potential candidate for electrode material of an electrochemical capacitor due to its distinctive nanoarchitectures and physiochemical properties. © 2020 Elsevier B.V.

We report the synthesis of titania nanofibers (TNF) of ?195 nm mean diameter doped with phosphorus through one-pot electrospinning followed by decoration of Ag nanoparticles (NPs). The Ag NPs of ?8 nm size on 2 % P-doped TNFs (Ag-PTNFs) showed excellent photocatalytic activity for the reduction of Cr(VI), under simulated solar light, with ?100 % conversion to Cr(III) in 90 min at pH 3 with a pseudo-first order rate constant of 0.085 min?1 that is 96.5 % higher than TNFs. The Ag-PTNFs also exhibited excellent photodegradation of methylene blue with pseudo-first order rate constant of 0.052 min?1 which is 82.7 % better than TNFs. The enhanced photocatalytic performance of Ag-PTNFs is attributed to the reduced band-gap, increased charge separation and reduced recombination rates. A proposed photocatalytic mechanism based on the synergistic effect of both Ag and P doping is presented which highlights the potential of these composite materials for water remediation. © 2020 Wiley-VCH GmbH

Residential buildings account for 17% of global greenhouse gas (GHG) emissions. With detached housing accounting for over 70% of all of Australia’s residential dwellings, and a projected doubling of population in the next 40 years, these houses represent a significant opportunity for GHG emissions reduction. Prefabrication can improve the environmental performance of buildings through lower resource input, reduction in waste and improved quality. However, little research exists on whether it reduces embodied GHG emissions, an increasingly significant proportion of a building’s life cycle GHG emissions. The aim of this study was to compare the embodied GHG emissions associated with the construction of detached residential housing in Australia using panelised prefabricated external wall systems. This study used a Path Exchange hybrid life cycle inventory approach to quantify the construction-related embodied GHG emissions of a typical detached house with three external wall assembly variations: cross laminated timber (CLT), structural insulated panels (SIPs) and prefabricated timber framed panels. Compared to conventional brick veneer construction, the prefabricated timber framed panel was the only one that lowered embodied GHG emissions (by 7%). The SIPs resulted in the highest embodied GHG emissions for the house (6% higher than the brick veneer option). The use of prefabrication may not always reduce GHG emissions associated with house construction. In reducing the initial embodied GHG emissions, while the construction process accounts for around 30% of these emissions, the key focus should be on selecting materials with low GHG emissions intensity.

Kinetic and isothermal biosorption studies of cobalt, copper and nickel ions using Polyalthia longifolia leaf powder has been carried out in this study on batch scale. Various factors like adsorbent dose, pH, initial concentration of metal ion and agitation time were optimized. Maximum biosorption of Cu(II), Co(II) and Ni(II) occurred at pH 6, 6 and 5, respectively. Isothermal models like Langmuir, Freundlich and Temkin were studied and observed to fit well. The maximum removing capacity of Polyalthia longifolia leaves was found to be 1.74, 3.99 and 4.08 mg/g for copper, cobalt and nickel ions, respectively following pseudo-second-order model. So, Polyalthia longifolia leaves found to besuitable for amputation of cobalt, copper and nickel ions in an environmentally benign way.