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AIMS To assess the efficacy and safety of iGlarLixi (the titratable fixed-ratio combination of insulin glargine 100 U/mL [iGlar] plus lixisenatide [Lixi]), in adults with type 2 diabetes (T2D) with glycated haemoglobin (HbA1c) levels ≥8% (≥64 mmol/mol). MATERIALS AND METHODS The LixiLan-O study (NCT02058147) compared iGlarLixi with iGlar or Lixi in adults with T2D inadequately controlled on metformin ± a second oral antidiabetes drug (OAD). This exploratory analysis evaluated the LixiLan-O subgroup of participants with baseline HbA1c levels of ≥8% (≥64 mmol/mol) who were receiving metformin plus a second OAD at screening. RESULTS The mean diabetes duration was 10.0 years, and the mean duration of second OAD use was 4.5 years. iGlarLixi demonstrated greater mean reductions from baseline in HbA1c and 2-hour postprandial glucose (PPG) compared with iGlar or Lixi (HbA1c -1.9% vs. -1.6% or -1.0% [-20 vs. -17 or -10 mmol/mol; 2-hour PPG -7.2 vs. -4.6 or -5.5 mmol/L). Greater proportions of participants achieved HbA1c

Background Fat embolism syndrome (FES) is a rare complication caused by the presence of fat particles in the microcirculation, which usually occurs within 12-72 h after trauma. At present, there have been few cases of fat embolism presenting within 3 h after trauma. Here, we report a case of femoral fracture complicated with an acute fat embolism caused by a car accident. Case summary A 29-year-old woman with pain, swelling and limited movement of her left lower limb after a car accident was taken by ambulance to our hospital. X-ray examination showed fracture of the middle and lower part of the left femur and fracture of the base of the left fifth metatarsal bone. She was hospitalized and admitted to the orthopedic ward. After the attending doctor performed tibial tubercle bone traction, the patient became confused, followed by respiratory distress. Finally, she was transferred to the intensive care unit. After nearly a month of treatment in the intensive care unit, the patient's cognitive function gradually recovered over 6 mo. Conclusion For patients with early traumatic fractures, young emergency physicians and orthopedics should be aware of the possibility of FES.

We report the design, fabrication and characterization of a 1.55-μm dual-wavelength Distributed Bragg Reflector (DBR) laser photonic integrated circuit (PIC) chip for continuous-waves (CW) terahertz generation. The PIC chip consists of a pair of parallel DBR lasers with integrated semiconductor optical amplifiers (SOA), and a multimode interference (MMI) coupler for combining the two wavelength channels into a single output waveguide. A room temperature continuous wave THz tuning range of 0.06 THz – 0.71 THz was obtained through optical heterodyne technique.

In this communication, we propose a tunable radar absorber based on the combination of a graphene capacitor with a varactor-loaded active frequency-selective surface (FSS). The absorbing amplitude and frequency can be independently controlled by changing the effective sheet resistance of graphene and the capacitance of the varactor through different bias voltages, respectively. We fabricated the designed absorber and measured its tunable reflectivity. The measured results indicate that the absorber can tune its absorbing frequency ranging from 3.53 to 7.05 GHz under normal incidence when changing bias voltages applied to the varactors from 0.5 to 10 V. By further varying the graphene resistance through the bias voltage, the absorbing amplitude at each absorbing frequency can be dynamically modulated. In addition, it is found that the absorber achieves polarization-insensitive characteristics due to the symmetrical design of the active FSS. The physical mechanism of this absorber is discussed by providing the equivalent transmission-line (TL) model.

Introduction Good quality basic life support (BLS) is associated with improved outcome from cardiac arrest. Chest compression fraction (CCF) is a BLS quality indicator, which may be influenced by the type of airway used. We aimed to assess CCF according to the airway strategy in the PARAMEDIC2 study: no advanced airway, supraglottic airway (SGA), tracheal intubation, or a combination of the two. Our hypothesis was that tracheal intubation was associated with a decrease in the CCF compared with alternative airway management strategies. Methods PARAMEDIC2 was a multicentre double-blinded placebo-controlled trial of adrenaline vs placebo in out-of-hospital cardiac arrest. Data showing compression rate and ratio from patients recruited by London Ambulance Service (LAS) as part of this study was collated and analysed according to the advanced airway used during the resuscitation attempt. Results CPR process data were available from 286/ 2058 (13.9%) of the total patients recruited by LAS. The mean compression rate for the first 5 min of data recording was the same in all groups (P = 0.272) and ranged from 104.2 (95% CI of mean: 100.5, 107.8) min−1 to 108.0 (95% CI of mean: 105.1, 108.3) min−1. The mean compression fraction was also similar across all groups (P = 0.159) and ranged between 74.7% and 78.4%. There was no difference in the compression rates and fractions across the airway management groups, regardless of the duration of CPR. Conclusion There was no significant difference in the compression fraction associated with the airway management strategy.

Background Supervised cardio-pulmonary rehabilitation may be safe and beneficial for people with pulmonary hypertension (PH) in groups 1 (pulmonary arterial hypertension) and 4 (chronic thromboembolic disease), particularly as a hospital in-patient. It has not been tested in the most common PH groups; 2 (left heart disease), 3 (lung disease), or 5 (other disorders). Further it has not been evaluated in the UK National Health Service (NHS) out-patient setting, or with long-term follow-up. The aim of this randomised controlled trial (RCT) is to test the clinical and cost-effectiveness of a supervised exercise rehabilitation intervention with psychosocial support compared to best practice usual care for people with PH in the community/outpatient setting. Methods This multi-centre, pragmatic, two-arm RCT with embedded process evaluation aims to recruit 352 clinically stable adults with PH (groups 1–5) and WHO functional class II-IV. Participants will be randomised to either the Supervised Pulmonary Hypertension Exercise Rehabilitation (SPHERe) intervention or control. The SPHERe intervention consists of 1) individual assessment and familiarisation sessions; 2) 8-week, twice-weekly, supervised out-patient exercise training; 3) psychosocial/motivational support and education; 4) guided home exercise plan. The control intervention consists of best practice usual care with a single one-to-one practitioner appointment, and general advice on physical activity. Outcomes will be measured at baseline, 4 months (post-intervention) and 12 months by researchers blinded to treatment allocation. The primary outcome is the incremental shuttle walk test at 4 months. Secondary outcomes include health-related quality of life (HRQoL), time to clinical worsening and health and social care use. A purposive sample of participants (n = 20 intervention and n = 20 control) and practitioners (n = 20) will be interviewed to explore experiences of the trial, outcomes and interventions. Discussion The SPHERe study is the first multi-centre clinical RCT to assess the clinical and cost effectiveness of a supervised exercise rehabilitation intervention compared to usual care, delivered in the UK NHS, for people in all PH groups. Results will inform clinicians and commissioners as to whether or not supervised exercise rehabilitation is effective and should be routinely provided for people with PH. Trial registration ISRCTN no. 10608766, prospectively registered on 18th March 2019.

Purpose:\ud To compare the effectiveness of the intravenous (IV) and intraosseous (IO) routes for drug administration in adults with a cardiac arrest enrolled in the Pre-Hospital Assessment of the Role of Adrenaline: Measuring the Effectiveness of Drug Administration in Cardiac Arrest (PARAMEDIC2) randomised, controlled trial.\ud \ud Methods:\ud Patients were recruited from five National Health Service Ambulance Services in England and Wales from December 2014 through October 2017. Patients with an out-of-hospital cardiac arrest who were unresponsive to initial resuscitation attempts were randomly assigned to 1 mg adrenaline or matching placebo. Intravascular access was established as soon as possible, and IO access was considered if IV access was not possible after two attempts.\ud \ud Results:\ud Among patients with out-of-hospital cardiac arrest, 3631 received adrenaline and 3686 received placebo. Amongst these, 1116 (30.1%) and 1121 (30.4%) received the study drug via the IO route. The odds ratios were similar in the IV and IO groups for return of spontaneous circulation (ROSC) at hospital handover [adjusted odds ratio (aOR) 4.07 (95% CI 3.42–4.85) and (aOR 3.98 (95% CI 2.86–5.53), P value for interaction 0.90]; survival to 30 days [aOR 1.67 (1.18–2.35) versus 0.9 (0.4–2.05), P = 0.18]; and favourable neurological outcome [aOR 1.39 (0.93–2.06) versus 0.62 (0.23–1.67), P = 0.14].\ud \ud Conclusion:\ud There was no significant difference in treatment effect (adrenaline versus placebo) on ROSC at hospital handover between drugs administered by the intraosseous route or by the intravenous route. We could not detect any difference in the treatment effect between the IV and IO routes on the longer term outcomes of 30-day survival or favourable neurological outcome at discharge (ISRCTN73485024).

The rock-climbing fish (Beaufortia kweichowensis) adheres to slippery, fouled surfaces and crawls both forward and backward in torrential streams. During locomotion, two suckers can be distinguished. Here, the general skeletal structure of the rock-climbing fish was determined using microtomography. Friction and adhesion were positively correlated, as were friction and fin ray angle. The unique adhesive locomotion system used by the rock-climbing fish was observed with a high speed camera. This system comprised two anisotropic suckers bearing two paired fins and two girdle muscles. A locomotion model was established based on these results. In this model, the fin states controlled the direction of motion using anisotropic friction, and alternate contractions of the girdle muscles provided propulsion during bidirectional crawling. This adhesive locomotion system was compared with other biological locomotion mechanisms. Based on these comparisons, we hypothesized that this novel system might represent an energy-saving solution for undulatory underwater vertical movement without detaching from the substrate.

The nonstructural antigen protein 3 of the hepatitis C virus (HCV NS3), commonly-used for HCV ELISA diagnosis, possesses protease and helicase activities. To prevent auto-degradation, a truncated NS3 protein was designed by removing the protease domain. Firstly, it was overexpressed in E. coli by IPTG induction under two different temperatures (25 and 37 °C), and purified using affinity chromatography to attain homogeneity above 90%. The molecular mass of purified protein was determined to be approx. 55 kDa. While lowering the temperature from 37 to 25 °C, the yield of the soluble fraction of HCV NS3 was increased from 4.15 to 11.1 mgL−1 culture, which also improved the antigenic activity and specificity. The protein stability was investigated after long-term storage (for 6 months at −20 °C) revealed no loss of activity, specificity, or antigenic efficacy. A thermal stability study on both freshly produced and stored HCV NS3 fractions at both temperatures showed that the unfolding curve profile properly obey the three-state unfolding mechanism. In the first transition phase, the midpoints of the thermal denaturation of fresh NS3 produced at 37 °C and 25 °C, and that produced after long-term storage at 37 °C and 25 °C, were 59.7 °C, 59.1 °C, 55.5 °C, and 57.8 °C, respectively. Microplates coated with the fresh NS3 produced at 25 °C or at 37 °C that were used for the HCV ELISA test and the diagnosis outcome were compared with two commercial kits—Abbott HCV EIA 2.0 and Ortho HCV EIA 3.0. Results indicated that the specificity of the HCV NS3 produced fresh at 25 °C was higher than that of the fresh one at 37 °C, hence showing potential for application in HCV ELISA diagnosis.

Background: Both continuous positive airway pressure (CPAP) and high-flow nasal oxygenation (HFNO) have been recommended for acute respiratory failure in COVID-19. However, uncertainty exists regarding effectiveness and safety. Methods: In the Recovery-Respiratory Support multi-center, three-arm, open-label, adaptive, randomized controlled trial, adult hospitalized patients with acute respiratory failure due to COVID-19, deemed suitable for treatment escalation, were randomly assigned to receive CPAP, HFNO, or conventional oxygen therapy. Comparisons were made between each intervention and conventional oxygen therapy. The primary outcome was a composite of tracheal intubation or mortality within 30-days. Results: Over 13-months, 1272 participants were randomized and analysed (380 (29.9%) CPAP; 417 (32.8%) HFNO; 475 (37.3%) conventional oxygen therapy). The need for tracheal intubation or mortality within 30-days was lower in the CPAP group (CPAP 137 of 377 participants (36.3%) vs conventional oxygen therapy 158 of 356 participants (44.4%); unadjusted odds ratio 0.72; 95% CI 0.53 to 0.96, P=0.03). There was no difference between HFNO and conventional oxygen therapy (HFNO 184 of 414 participants (44.4%) vs conventional oxygen therapy 166 of 368 participants (45.1%); unadjusted odds ratio 0.97; 95% CI 0.73 to 1.29, P=0.85). Conclusions: CPAP, compared with conventional oxygen therapy, reduced the composite outcome of intubation or death within 30 days of randomisation in hospitalized adults with acute respiratory failure due to COVID-19. No effect was observed with the use of HFNO. (Funded by the UK National Institute for Health Research; ISRCTN 16912075).

BackgroundBoth continuous positive airway pressure (CPAP) and high-flow nasal oxygenation (HFNO) have been recommended for acute respiratory failure in COVID-19. However, uncertainty exists regarding effectiveness and safety.MethodsIn the Recovery-Respiratory Support multi-center, three-arm, open-label, adaptive, randomized controlled trial, adult hospitalized patients with acute respiratory failure due to COVID-19, deemed suitable for treatment escalation, were randomly assigned to receive CPAP, HFNO, or conventional oxygen therapy. Comparisons were made between each intervention and conventional oxygen therapy. The primary outcome was a composite of tracheal intubation or mortality within 30-days.ResultsOver 13-months, 1272 participants were randomized and included in the analysis (380 (29.9%) CPAP; 417 (32.8%) HFNO; 475 (37.3%) conventional oxygen therapy). The need for tracheal intubation or mortality within 30-days was lower in the CPAP group (CPAP 137 of 377 participants (36.3%) vs conventional oxygen therapy 158 of 356 participants (44.4%); unadjusted odds ratio 0.72; 95% CI 0.53 to 0.96, P=0.03). There was no difference between HFNO and conventional oxygen therapy (HFNO 184 of 414 participants (44.4%) vs conventional oxygen therapy 166 of 368 participants (45.1%); unadjusted odds ratio 0.97; 95% CI 0.73 to 1.29, P=0.85).ConclusionsCPAP, compared with conventional oxygen therapy, reduced the composite outcome of intubation or death within 30 days of randomisation in hospitalized adults with acute respiratory failure due to COVID-19. There was no effect observed, compared with conventional oxygen therapy, with the use of HFNO.(Funded by the UK National Institute for Health Research; ISRCTN 16912075).

Fast-charged energy-storage technologies have become important nowadays as they are required by many applications, including automobiles. This inspires the exploitation of hybrid supercapacitors (HSCs) with the advantages of fast charge offered by the capacitor characters and high energy density from the property of battery technology. The challenges lay in the construction of advanced materials with high pseudocapacitive activity. Herein, a metal-organic framework derivative is utilized to address the problems. Specifically, polyhedral CoNi layered double hydroxide (CoNi-LDHx) cages assembled in the form of nanosheet arrays are prepared from ZIF-67 using a facile ion-exchange approach. Based on the control over the mass ratio of ZIF-67 to Ni salt, the optimal CoNi-LDH2 is attained. It exhibits ultrahigh capacities ranging from 1031.4 to 667.3 C g-1 under 1-25 A g-1, thanks to rich Faradaic active spots and the accelerated kinetics provided by the synergy between nanosheet arrays and the hollow structure. The CoNi-LDH2-based HSC with the gel electrolyte shares remarkable energy output of 49 Wh kg-1 and approving cyclability with almost no capacity decay after 12 000 cycles. This is an advancement vs many related studies and can arouse tremendous interests of researchers in solving the main problems of energy storage.

Importance Platelet-rich plasma injections are used as a treatment for chronic midportion Achilles tendinopathy, but evidence for this treatment is limited. Objective In adults with midportion Achilles tendinopathy, to assess the effects of a single platelet-rich plasma injection, compared with sham injection, on the outcome of the Victorian Institute of Sport Assessment-Achilles (VISA-A) score (a single composite measure of Achilles tendinopathy severity). Design, Setting, and Participants A participant-blinded, multicenter randomized clinical trial that included 240 people from 24 sites assigned to either a platelet-rich plasma injection or a sham injection between April 2016 and February 2020. Final follow-up was July 2020. Participants were older than 18 years with midportion Achilles tendon pain for more than 3 months as confirmed by ultrasound, magnetic resonance imaging, or both. Interventions A single intratendinous platelet-rich plasma injection (n = 121) or a single sham injection (insertion of a subcutaneous dry needle not entering the tendon) (n = 119). Main Outcomes and Measures The primary outcome was the VISA-A score, measured 6 months after treatment allocation. The VISA-A score contains 8 questions that cover 3 domains of pain, function, and activity, analyzed as a composite score (range, 0 [worst symptoms] to 100 [no symptoms]; minimal clinically important difference in score, 12 points). The primary analysis was adjusted for laterality, age, sex, and baseline VISA-A score. Results Among 240 patients assigned to a platelet-rich plasma or sham injection (mean age, 52 years; 138 [58%] women), 221 (92%) completed the trial. At 6-month follow-up, mean VISA-A score values in the plasma-rich plasma group vs the sham injection group were 54.4 vs 53.4 (adjusted mean difference, −2.7 [95% CI, −8.8 to 3.3]). The most common adverse events compared between patients in the platelet-rich plasma group vs the sham group were injection site discomfort (97 vs 73 patients), swelling (56 vs 52 patients) and bruising (48 vs 49 patients). Conclusions and Relevance Among patients with chronic midportion Achilles tendinopathy, treatment with a single injection of intratendinous platelet-rich plasma, compared with insertion of a subcutaneous dry needle, did not reduce Achilles tendon dysfunction at 6 months. These findings do not support the use of this treatment for chronic midportion Achilles tendinopathy. Trial Registration isrctn.org Identifier:ISRCTN13254422

Background Falls and fractures are a major problem. Objectives To investigate the clinical effectiveness and cost-effectiveness of alternative falls prevention interventions. Design Three-arm, pragmatic, cluster randomised controlled trial with parallel economic analysis. The unit of randomisation was the general practice. Setting Primary care. Participants People aged ≥ 70 years. Interventions All practices posted an advice leaflet to each participant. Practices randomised to active intervention arms (exercise and multifactorial falls prevention) screened participants for falls risk using a postal questionnaire. Active treatments were delivered to participants at higher risk of falling. Main outcome measures The primary outcome was fracture rate over 18 months, captured from Hospital Episode Statistics, general practice records and self-report. Secondary outcomes were falls rate, health-related quality of life, mortality, frailty and health service resource use. Economic evaluation was expressed in terms of incremental cost per quality-adjusted life-year and incremental net monetary benefit. Results Between 2011 and 2014, we randomised 63 general practices (9803 participants): 21 practices (3223 participants) to advice only, 21 practices (3279 participants) to exercise and 21 practices (3301 participants) to multifactorial falls prevention. In the active intervention arms, 5779 out of 6580 (87.8%) participants responded to the postal fall risk screener, of whom 2153 (37.3%) were classed as being at higher risk of falling and invited for treatment. The rate of intervention uptake was 65% (697 out of 1079) in the exercise arm and 71% (762 out of 1074) in the multifactorial falls prevention arm. Overall, 379 out of 9803 (3.9%) participants sustained a fracture. There was no difference in the fracture rate between the advice and exercise arms (rate ratio 1.20, 95% confidence interval 0.91 to 1.59) or between the advice and multifactorial falls prevention arms (rate ratio 1.30, 95% confidence interval 0.99 to 1.71). There was no difference in falls rate over 18 months (exercise arm: rate ratio 0.99, 95% confidence interval 0.86 to 1.14; multifactorial falls prevention arm: rate ratio 1.13, 95% confidence interval 0.98 to 1.30). A lower rate of falls was observed in the exercise arm at 8 months (rate ratio 0.78, 95% confidence interval 0.64 to 0.96), but not at other time points. There were 289 (2.9%) deaths, with no differences by treatment arm. There was no evidence of effects in prespecified subgroup comparisons, nor in nested intention-to-treat analyses that considered only those at higher risk of falling. Exercise provided the highest expected quality-adjusted life-years (1.120), followed by advice and multifactorial falls prevention, with 1.106 and 1.114 quality-adjusted life-years, respectively. NHS costs associated with exercise (£3720) were lower than the costs of advice (£3737) or of multifactorial falls prevention (£3941). Although incremental differences between treatment arms were small, exercise dominated advice, which in turn dominated multifactorial falls prevention. The incremental net monetary benefit of exercise relative to treatment valued at £30,000 per quality-adjusted life-year is modest, at £191, and for multifactorial falls prevention is £613. Exercise is the most cost-effective treatment. No serious adverse events were reported. Limitations The rate of fractures was lower than anticipated. Conclusions Screen-and-treat falls prevention strategies in primary care did not reduce fractures. Exercise resulted in a short-term reduction in falls and was cost-effective. Future work Exercise is the most promising intervention for primary care. Work is needed to ensure adequate uptake and sustained effects. Trial registration Current Controlled Trials ISRCTN71002650. Funding This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 34. See the NIHR Journals Library website for further project information.

Background Adrenaline has been used as a treatment for cardiac arrest for many years, despite uncertainty about its effects on long-term outcomes and concerns that it may cause worse neurological outcomes. Objectives The objectives were to evaluate the effects of adrenaline on survival and neurological outcomes, and to assess the cost-effectiveness of adrenaline use. Design This was a pragmatic, randomised, allocation-concealed, placebo-controlled, parallel-group superiority trial and economic evaluation. Costs are expressed in Great British pounds and reported in 2016/17 prices. Setting This trial was set in five NHS ambulance services in England and Wales. Participants Adults treated for an out-of-hospital cardiac arrest were included. Patients were ineligible if they were pregnant, if they were aged Interventions Participants were randomised to either adrenaline (1 mg) or placebo in a 1 : 1 allocation ratio by the opening of allocation-concealed treatment packs. Main outcome measures The primary outcome was survival to 30 days. The secondary outcomes were survival to hospital admission, survival to hospital discharge, survival at 3, 6 and 12 months, neurological outcomes and health-related quality of life through to 6 months. The economic evaluation assessed the incremental cost per quality-adjusted life-year gained from the perspective of the NHS and Personal Social Services. Participants, clinical teams and those assessing patient outcomes were masked to the treatment allocation. Results From December 2014 to October 2017, 8014 participants were assigned to the adrenaline (n = 4015) or to the placebo (n = 3999) arm. At 30 days, 130 out of 4012 participants (3.2%) in the adrenaline arm and 94 out of 3995 (2.4%) in the placebo arm were alive (adjusted odds ratio for survival 1.47, 95% confidence interval 1.09 to 1.97). For secondary outcomes, survival to hospital admission was higher for those receiving adrenaline than for those receiving placebo (23.6% vs. 8.0%; adjusted odds ratio 3.83, 95% confidence interval 3.30 to 4.43). The rate of favourable neurological outcome at hospital discharge was not significantly different between the arms (2.2% vs. 1.9%; adjusted odds ratio 1.19, 95% confidence interval 0.85 to 1.68). The pattern of improved survival but no significant improvement in neurological outcomes continued through to 6 months. By 12 months, survival in the adrenaline arm was 2.7%, compared with 2.0% in the placebo arm (adjusted odds ratio 1.38, 95% confidence interval 1.00 to 1.92). An adjusted subgroup analysis did not identify significant interactions. The incremental cost-effectiveness ratio for adrenaline was estimated at £1,693,003 per quality-adjusted life-year gained over the first 6 months after the cardiac arrest event and £81,070 per quality-adjusted life-year gained over the lifetime of survivors. Additional economic analyses estimated incremental cost-effectiveness ratios for adrenaline at £982,880 per percentage point increase in overall survival and £377,232 per percentage point increase in neurological outcomes over the first 6 months after the cardiac arrest. Limitations The estimate for survival with a favourable neurological outcome is imprecise because of the small numbers of patients surviving with a good outcome. Conclusions Adrenaline improved long-term survival, but there was no evidence that it significantly improved neurological outcomes. The incremental cost-effectiveness ratio per quality-adjusted life-year exceeds the threshold of £20,000–30,000 per quality-adjusted life-year usually supported by the NHS. Future work Further research is required to better understand patients’ preferences in relation to survival and neurological outcomes after out-of-hospital cardiac arrest and to aid interpretation of the trial findings from a patient and public perspective. Trial registration Current Controlled Trials ISRCTN73485024 and EudraCT 2014-000792-11. Funding This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 25. See the NIHR Journals Library website for further project information.

Background:\ud Newly-developed suction-based airway clearance devices potentially provide a novel way to improve outcome in patients with foreign body airway obstruction. We conducted a randomised controlled crossover manikin trial to compare the efficacy and usability of two of these devices with abdominal thrusts.\ud \ud Methods:\ud We randomised participants from a UK medical school to one of six groups which determined the order in which participants attempted the three techniques (abdominal thrusts; LifeVac, Nesconset, New York, USA; Dechoker, Concord North Carolina, USA). Randomisation was performed using an online randomisation system. Following brief training, participants sought to remove a foreign body airway obstruction from a manikin using the allocated technique. The primary outcome was successful removal of the foreign body. Usability was assessed in a questionnaire following the three simulations.\ud \ud Results:\ud We randomised and analysed data from 90 participants (58% male; 86% aged 18−29 years). Compared with abdominal thrusts, successful foreign body airway obstruction removal was achieved more frequently in manikins in the LifeVac group (odds ratio 47.32, 95% CI 5.75–389.40) but not in the Dechoker group (odds ratio 1.22, 95% CI 0.60–2.47). The usability of LifeVac and abdominal thrusts were generally evaluated more positively than the Dechoker.\ud \ud Conclusion:\ud In this manikin study, we found that, compared with abdominal thrusts, the success rate for foreign body airway obstruction removal was higher in the LifeVac group but not in the Dechoker group.

The primary objective is to determine which of two interventions: 1) an eight week, online, home-based, supervised, group rehabilitation programme (REGAIN); or 2) a single online session of advice (best-practice usual care); is the most clinically and cost-effective treatment for people with ongoing COVID-19 sequelae more than three months after hospital discharge. Multi-centre, 2-arm (1:1 ratio) parallel group, randomised controlled trial with embedded process evaluation and health economic evaluation. Adults with ongoing COVID-19 sequelae more than three months after hospital discharge Inclusion criteria: 1) Adults ≥18 years; 2) ≥ 3 months after any hospital discharge related to COVID-19 infection, regardless of need for critical care or ventilatory support; 3) substantial (as defined by the participant) COVID-19 related physical and/or mental health problems; 4) access to, and able/supported to use email and internet audio/video; 4) able to provide informed consent; 5) able to understand spoken and written English, Bengali, Gujarati, Urdu, Punjabi or Mandarin, themselves or supported by family/friends. Exclusion criteria: 1) exercise contraindicated; 2) severe mental health problems preventing engagement; 3) previous randomisation in the present study; 4) already engaged in, or planning to engage in an alternative NHS rehabilitation programme in the next 12 weeks; 5) a member of the same household previously randomised in the present study. Intervention 1: The Rehabilitation Exercise and psycholoGical support After covid-19 InfectioN (REGAIN) programme: an eight week, online, home-based, supervised, group rehabilitation programme. Intervention 2: A thirty-minute, on-line, one-to-one consultation with a REGAIN practitioner (best-practice usual care). The primary outcome is health-related quality of life (HRQoL) – PROMIS® 29+2 Profile v2.1 (PROPr) – measured at three months post-randomisation. Secondary outcomes include dyspnoea, cognitive function, health utility, physical activity participation, post-traumatic stress disorder (PTSD) symptom severity, depressive and anxiety symptoms, work status, health and social care resource use, death - measured at three, six and 12 months post-randomisation. Participants will be randomised to best practice usual care or the REGAIN programme on a 1:1.03 basis using a computer-generated randomisation sequence, performed by minimisation and stratified by age, level of hospital care, and case level mental health symptomatology. Once consent and baseline questionnaires have been completed by the participant online at home, randomisation will be performed automatically by a bespoke web-based system. To ensure allocation concealment from both participant and REGAIN practitioner at baseline, randomisation will be performed only after the baseline questionnaires have been completed online at home by the participant. After randomisation has been performed, participants and REGAIN practitioners cannot be blind to group allocation. Follow-up outcome assessments will be completed by participants online at home. A total of 535 participants will be randomised: 263 to the best-practice usual care arm, and 272 participants to the REGAIN programme arm. Current protocol: Version 3.0 (27th October 2020) Recruitment will begin in December 2020 and is anticipated to complete by September 2021. ISRCTN:11466448 , 23rd November 2020 The full protocol Version 3.0 (27th October 2020) is attached as an additional file, accessible from the Trials website (Additional file 1). In the interests of expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol. The study protocol has been reported in accordance with the Standard Protocol Items: Recommendations for Clinical Interventional Trials (SPIRIT) guidelines.

Direct growth of graphene on insulating substrate is highly desired for practical applications in two-dimensional electronics and optoelectronics. However, the controllable synthesis of large scale graphene films on dielectrics is still limited in thickness and crystallinity by the absence of catalyst. Here we develop a transfer-free method to synthesize continuous graphene films on various insulating substrates by using molten Ga-Pd alloy and silicon carbide (SiC) as catalyst and carbon source. The catalytic Ga-Pd alloy induces the decomposition of Si C bonds and promotes the formation of C-C sp2 at relatively low temperature around 1000 °C. The suitable carbon solubility of Ga-Pd alloy could also promote the fabrication of few-layer graphene films on the interface between alloy and SiC substrate as well as the upper surface of alloy. Furthermore, this strategy could be extended to the interfacial growth of graphene on other dielectrics by simply placing the substrate face down to the surface of molten alloy. The progress of this work may help to understand the mechanism of molten Ga-Pd alloy catalyzed interfacial growth of transfer-free graphene and benefit the application of graphene-based electronics and photonics in the future.

The general method to achieve electromagnetic (EM) invisibility is to use absorbing materials that can reduce the backscattering microwave signals. However, they will influence the transmission of useful signals, and their passive operation mode also blocks the realization of active camouflage systems. Here, the authors propose an electrically tunable metadevice which can dynamically manipulate the reflection magnitude and realize high-efficiency transmission at two distinctive frequency bands. Such a metadevice is driven by graphene sandwich structure integrated with multi-layer metasurface. By electrically controlling the sheet resistance of graphene, the authors have experimentally verified that the metadevice can tune the reflection magnitude from -5 to -20 dB over a wide frequency band of 5-15 GHz, and meanwhile realize a high transparent EM window with 3-dB transmission band covering from 23 to 25 GHz. The operation mechanism is discussed by examining the electric field distribution and also employing an equivalent circuit model to analyze the input impedance. Furthermore, using the developed metadevice, the authors still demonstrate its dynamical camouflaging performance and application potential as an antenna radome by experiment. The finding in this study is expected to trigger great interest in adaptive camouflage, stealth radome, and multifunctional EM manipulation fields.

Aims We recently reported early outcomes in patients enrolled in a randomised trial of adrenaline in out-of-hospital cardiac arrest: the PARAMEDIC2 (Prehospital Assessment of the Role of Adrenaline: Measuring the Effectiveness of Drug Administration in Cardiac Arrest) trial. The purpose of the present paper is to report long-term survival, quality of life, functional and cognitive outcomes at 3, 6 and 12-months. Methods PARAMEDIC2 was a pragmatic, individually randomised, double blind, controlled trial with an economic evaluation. Patients were randomised to either adrenaline or placebo. This paper reports results on the modified Rankin Scale scores at 6-months, survival at 6 and 12-months, as well as other cognitive, functional and quality of life outcomes collected at 3 and 6 months (Two Simple Questions, the Mini Mental State Examination, the Informant Questionnaire on Cognitive Decline Evaluation for Cardiac Arrest, Hospital Anxiety and Depression Scale, the Post Traumatic Stress Disorder Checklist - Civilian Version, Short-Form 12-item Health Survey and the EuroQoL EQ-5D-5L). Results 8014 patients were randomised with confirmed trial drug administration. At 6-months, 78 (2.0%) of the patients in the adrenaline group and 58 (1.5%) of patients in the placebo group had a favourable neurological outcome (adjusted odds ratio 1.35 [95% confidence interval: 0.93, 1.97]). 117 (2.9%) patients were alive at 6-months in the adrenaline group compared with 86 (2.2%) in the placebo group (1.43 [1.05, 1.96], reducing to 107 (2.7%) and 80 (2.0%) respectively at 12-months (1.38 [1.00, 1.92]). Measures of 3 and 6-month cognitive, functional and quality of life outcomes were reduced, but there was no strong evidence of differences between groups. Conclusion Adrenaline improved survival through to 12-months follow-up. The study did not find evidence of improvements in favourable neurological outcomes. (ISCRTN 73485024)

Objective The trial objective is to determine if Continuous Positive Airway Pressure (CPAP) or High-Flow Nasal Oxygen (HFNO) is clinically effective compared to standard oxygen therapy in patients with confirmed or suspected COVID-19. Trial design Adaptive (group-sequential), parallel group, pragmatic, superiority randomised controlled, open-label, multi-centre, effectiveness trial. Participants The trial is being conducted across approximately 60 hospitals across England, Wales, Scotland, and Northern Ireland. Inpatients at participating hospitals are eligible to participate if they have respiratory failure with suspected or proven COVID-19, and meet all of the inclusion criteria and none of the exclusion criteria. Inclusion criteria: 1) Adults ≥ 18 years; 2) Admitted to hospital with suspected or proven COVID-19; 3) Receiving oxygen with fraction of inspired oxygen (FiO2) ≥0.4 and peripheral oxygen saturation (SpO2) ≤94%; and 4) Plan for escalation to tracheal intubation if needed. Exclusion criteria: 1) Planned tracheal intubation and mechanical ventilation imminent within 1 hour; 2) Known or clinically apparent pregnancy; 3) Any absolute contraindication to CPAP or HFNO; 4) Decision not to intubate due to ceiling of treatment or withdrawal of treatment anticipated; and 5) Equipment for both CPAP and HFNO not available. Intervention and comparator Intervention one: Continuous positive airway pressure delivered by any device. Set-up and therapy titration is not protocolised and is delivered in accordance with clinical discretion. Intervention two: High-flow nasal oxygen delivered by any device. Set-up and therapy titration is not protocolised and is delivered in accordance with clinical discretion. Comparator group: Standard care- oxygen delivered by face mask or nasal cannula (excluding the use of continuous positive airway pressure or high-flow nasal oxygen). Set-up and therapy titration is not protocolised and is delivered in accordance with clinical discretion. Intervention delivery continues up to the point of death, tracheal intubation, or clinical determination that there is no ongoing need (palliation or improvement). Main outcomes The primary outcome is a composite outcome comprising tracheal intubation or mortality within 30 days following randomisation. Secondary outcomes include tracheal intubation rate, time to tracheal intubation, duration of invasive ventilation, mortality rate, time to mortality, length of hospital stay, and length of critical care stay. Randomisation Participants are randomised in a 1:1:1 ratio to receive either continuous positive airway pressure, high-flow nasal oxygen or standard care. Due to the challenging environment of study delivery, a specific intervention may not always be available at the hospital site. The study uses two integrated randomisation systems to allow, where required, the site to randomise between all three interventions, between CPAP and standard care, and between HFNO and standard care. System integration ensures maintenance of balance between interventions. Randomisation is performed using a telephone-based interactive voice response system to maintain allocation concealment. The randomisation sequence was computer-generated using the minimisation method. Participant randomisation is stratified by site, gender (M/F), and age (=50 years). Blinding (masking) The nature of the trial interventions precludes blinding of the researcher, patient and clinical team. Primary and secondary outcomes are all objective outcomes, thereby minimising the risk of detection bias. Numbers to be randomised (sample size) 4002 participants (1334 to be randomized to each of the three study arms) Trial Status Current protocol: Version 4.0, 29th May 2020. Recruitment began on April 6, 2020 and is anticipated to be complete by April 5, 2021. The trial has been awarded Urgent Public Health status by the National Institute of Health Research on 13th April 2020. Trial registration ISRCTN, ISRCTN16912075. Registered 6th April 2020, http://www.isrctn.com/ISRCTN16912075 Full protocol The full protocol (version 4.0, 29th May 2020) is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol. The study protocol has been reported in accordance with the Standard Protocol Items: Recommendations for Clinical Interventional Trials (SPIRIT) guidelines (Additional file 2).

Purpose To examine the time to drug administration in patients with a witnessed cardiac arrest enrolled in the Pre-Hospital Assessment of the Role of Adrenaline: Measuring the Effectiveness of Drug Administration in Cardiac Arrest (PARAMEDIC2) randomised controlled trial. Methods The PARAMEDIC2 trial was undertaken across 5 NHS ambulance services in England and Wales with randomisation between December 2014 and October 2017. Patients with an out-of-hospital cardiac arrest who were unresponsive to initial resuscitation attempts were randomly assigned to 1 mg intravenous adrenaline or matching placebo according to treatment packs that were identical apart from treatment number. Participants and study staff were masked to treatment allocation. Results 8016 patients were enrolled, 4902 sustained a witnessed cardiac arrest of whom 2437 received placebo and 2465 received adrenaline. The odds of return of spontaneous circulation decreased in both groups over time but at a greater rate in the placebo arm odds ratio (OR) 0.93 (95% CI 0.92–0.95) compared with the adrenaline arm OR 0.96 (95% CI 0.95–0.97); interaction OR: 1.03, 95% CI 1.01–1.05, p = 0.005. By contrast, although the rate of survival and favourable neurological outcome decreased as time to treatment increased, the rates did not differ between the adrenaline and placebo groups. Conclusion The rate of return of spontaneous circulation, survival and favourable neurological outcomes decrease over time. As time to drug treatment increases, adrenaline increases the chances of return of spontaneous circulation. Longer term outcomes were not affected by the time to adrenaline administration. (ISRCTN73485024). Electronic supplementary material The online version of this article (10.1007/s00134-019-05836-2) contains supplementary material, which is available to authorized users.

Background Phase III trials often require large sample sizes, leading to high costs and delays in clinical decision-making. Group sequential designs can improve trial efficiency by allowing for early stopping for efficacy and/or futility and thus may decrease the sample size, trial duration and associated costs. Bayesian approaches may offer additional benefits by incorporating previous information into the analyses and using decision criteria that are more practically relevant than those used in frequentist approaches. Frequentist group sequential designs have often been used for phase III studies, but the use of Bayesian group sequential designs is less common. The aim of this work was to explore how Bayesian group sequential designs could be constructed for phase III trials conducted in emergency medicine. Methods The PARAMEDIC2 trial was a phase III randomised controlled trial that compared the use of adrenaline to placebo in out-of-hospital cardiac arrest patients on 30-day survival rates. It used a frequentist group sequential design to allow early stopping for efficacy or harm. We constructed several alternative Bayesian group sequential designs and studied their operating characteristics via simulation. We then virtually re-executed the trial by applying the Bayesian designs to the PARAMEDIC2 data to demonstrate what might have happened if these designs had been used in practice. Results We produced three alternative Bayesian group sequential designs, each of which had greater than 90% power to detect the target treatment effect. A Bayesian design which performed interim analyses every 500 patients recruited produced the lowest average sample size. Using the alternative designs, the PARAMEDIC2 trial could have declared adrenaline superior for 30-day survival with approximately 1500 fewer patients. Conclusions Using the PARAMEDIC2 trial as a case study, we demonstrated how Bayesian group sequential designs can be constructed for phase III emergency medicine trials. The Bayesian framework enabled us to obtain efficient designs using decision criteria based on the probability of benefit or harm. It also enabled us to incorporate information from previous studies on the treatment effect via the prior distributions. We recommend the wider use of Bayesian approaches in phase III clinical trials. Trial registration PARAMEDIC2 Trial registration ISRCTN, ISRCTN73485024. Registered 13 March 2014, http://www.isrctn.com/ISRCTN73485024

In this communication, we propose a method to achieve high-efficiency transmission and wideband scattering reduction at two distinctive frequency bands by combining frequency-selective surface (FSS) and electromagnetic bandgap (EBG) surface. Such FSS-EBG surface is composed of two-layered metallic patterns. The bottom FSS layer works as a filter for allowing in-band signal to pass and reflecting out-of-band signal, while the top EBG layer adopts 0 and $\pi $ reflection phase cells with a chessboard distribution to reduce the backward scattering wave. As a proof-of-concept demonstration, the planar and cylindrical surfaces are, respectively, designed to verify such two functionalities. Our FSS-EBG surface can make the antenna signal transmit at S-band with small insertion loss and simultaneously provide wideband low-scattering property at X–Ku band, which is suitable to be used as the stealth antenna radome. In addition, the possibility of integrating polarization conversion function into the passing band is numerically demonstrated.

We demonstrate a distributed reflector (DR) laser with the distributed feedback (DFB) section and the distributed Bragg reflector (DBR) section sharing the same multiple-quantum-well structure. The DR laser exhibits a stable dynamic single-longitudinal mode characteristic. A direct modulation bandwidth of 27 GHz is obtained through the detuned-loading effect and photon–photon resonance effect. The fabrication process of the DR laser is simplified due to the identical active layer structure and the uniform grating in the DFB and DBR sections.

The drying of energetic materials is an essential and hazardous process involving complicated heat and mass transfer. In this paper, the drying properties of Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) are investigated using a novel developed continuous dryer which can be applied for the drying of both hazardous powders and ordinary powders. The results reveal that a distinct falling rate period occurs following a short increasing rate period with no any constant rate drying period, greatly shortening the drying time. Ten different thin-drying mathematical models are tested by the drying curve fitting and Midilli-Kucuk model with the higher R, EF and the lower MBE, RMSE and χ 2 is selected as the most adequate model for describing the thin layer drying of RDX. Effective moisture diffusivities are in the range of 3.16 × 10−8–3.46 × 10−8 m2/s. It is confirmed that drying monitoring values are well inside the security perimeter with lower temperature (less than 90 °C), electrostatic charge (at a desired level) and dust (reduced by 85.6%). Compared to the original static tray drying, the continuous drying of RDX in the novel dryer exhibits a great superiority for energy saving and cost saving with the falls of 59.7% and 13.7% respectively.

A monolithically integrated four-channel directly modulated laser (DML) array working at the 1.3-μm band is demonstrated. The laser was manufactured by using the techniques of selective area growth (SAG) of the upper separate confinement heterostructure (Upper-SCH) and modified butt-joint method. The fabricated device showed stable single mode operation with the side mode suppression ratio (SMSR) >35 dB, and high wavelength accuracy with the deviations from the linear fitted values 7 GHz was obtained, which may be suitable for 40 GbE applications in the 1.3-μm band.

In this paper, a broadband and tunable radar cross section (RCS) reduction structure is proposed by using the hybrid physical mechanism that is based on high-order reflections and Salisbury-type absorption. Our design combines the high-index grating structure with a traditional Salisbury screen in which the lossy sheet is made of a graphene structure. When it is illuminated by a plane wave with normal incidence, the Salisbury screen can absorb the incoming wave, and the introducing high-index grating structure could further reduce the backward scattering wave by generating high-order reflection beams, which broadens the RCS reduction bandwidth. In addition, the RCS reduction level can be dynamically controlled by tuning the surface resistance of the graphene layer. Simulated results show that the proposed structure can realize tunable RCS reduction between 4.1 and 18 GHz under normal incidence with different graphene resistances. Experimental results are in accordance with those of the simulation results. In addition, the scattering field distributions and the plots of surface power loss density have been illustrated to analyze the RCS-reduction mechanism of our structure.

We report a low-cost arrayed waveguide grating (AWG) based mode-locked semiconductor laser designed for multichannel synchronous ultrashort pulse generation. Both the fabrication process and chip characterization results are discussed in detail. By deploying a bundle active–passive photonic integration technique, only one regrowth step is required to monolithically integrate a semiconductor optical amplifier array, an AWG, and a common saturable absorber on a single InP substrate. Combined with a shallow ridge waveguide structure common for both active and passive sections and formed in a single dry etching process, our process allows the fabrication of the monolithic photonic integrated circuit chip in a much simplified process. The fabricated device demonstrated multichannel mode-locking operation at a repetition frequency of 4.1 GHz in a fundamental mode-locking regime under both passive mode-locking and synchronous hybrid mode-locking conditions. Timing jitter as low as 1 ps was obtained, and preliminary pulse chirping characteristics were analyzed by a frequency-resolved optical gating technique. The exhibited performance makes our device a promising candidate as a multichannel ultrashort pulse optical source for future cost-effective high-speed optical networking and signal processing applications .

We report on ultra-short pulse single-section mode-locked lasers emitting at 1.55 μm, based on self-assembled InAs/InGaAsP/InP quantum dot active regions grown by metal-organic vapor phase epitaxy (MOVPE). For a 1.5-mm-long Fabry-Perot laser, mode-locking at a repetition rate of 29.8 GHz with pulse duration of 855 fs is obtained without any external pulse compression techniques. The mode-beating exhibits a narrow RF linewidth less than 30 kHz, and a wide frequency tuning range up to 73 MHz can be achieved by simply changing the injection current. Moreover, a higher repetition rate of 55.6 GHz and the transform limited Gaussian-pulse with the 707 fs pulse duration are achieved from a device with a shorter cavity length of 0.8 mm.

We demonstrate an ultrashort pulse and high power single-section mode-locked laser using chirped multiple InAs/InP quantum dot (QD) layers as the active region of the laser. The chirped QD active region consists of seven layers of InAs QDs of different heights, which is beneficial in broadening the material gain spectrum. A transform-limited Gaussian pulse with a pulse duration of 322 fs is obtained from a device of 1 mm in length. Moreover, the femtosecond pulse with highest peak power of 6.8 W is achieved for the 45.5-GHz mode-locked laser. These results show the potential of the mode-locked laser for femtosecond pulse generation with high peak power and high repetition rate in the 1.55- $\mu \text{m}$ wavelength band.

We report a novel arrayed waveguide grating (AWG)-based $4\,\times \,12$ GHz multichannel harmonically mode-locked semiconductor laser operating near 1535 nm, which was realized by monolithically integrating a semiconductor optical amplifier (SOA) array, a set of passive optical delay lines, an AWG with 400 GHz channel spacing, a saturable absorber, and a common output SOA. Our device layout and fabrication were completed on the European JePPIX InP photonic integration platform, based on the multiproject wafer run foundry approach. We demonstrated four wavelength channels operating in the fifth harmonic mode-locking regime. Channel repetition rate of 12 GHz and 3-dB RF linewidth as narrow as 6 kHz were obtained. The exhibited performance makes our device a very promising candidate as an ultracompact multichannel light source for future hybrid optical time and wavelength division multiplexing, high-speed photonic analog-to-digital conversion, and optical clock recovery applications.

We demonstrate a four-wavelength distributed feedback (DFB) diode laser array integrated with a semiconductor optical amplifier (SOA) for widely tunable terahertz (THz) mode-beating generation. The InP-based monolithically integrated chip consists of DFB laser diodes, an SOA, and a multimode interference (MMI) coupler. Microheaters and electrode plates are integrated on top of each DFB section for continuous and independent wavelength tuning. By heterodyning the output from the DFB lasers on a Uni-Traveling Carrier Photodiode (UTC-PD) integrated antenna, a continuous THz radiation ranging from 0.1 to 2.25 THz was obtained.

A two-phase flow ejector is an important part of a water mist fire suppression system, and these devices have become a popular research topic in recent years. This paper proposes a supersonic ejector that aims to improve the efficiency of water mist fire suppression systems. The effects of ejector geometric parameters on the entrainment ratio (ER) were explored. The effects of primary flow pressure (PP) on the mixing process and flow phenomena were studied by a high-speed camera. The experimental results show that the ER first increases and then decreases with increasing PP. ER increases with increasing ejector area ratio (AR). The PP corresponding to the maximum ER of ejectors with a different nozzle exit position (NXP) is 3.6 bar. The ejector with an NXP of +1 and AR of 6 demonstrate the best performance, and the ER of this ejector reaches 36.29. The spray half-cone angle of the ejector increases with increasing ER, reaching a maximum value of 7.07&deg, The unstable atomization half-cone angle is mainly due to a two-phase flow pulsating phenomenon. The pulsation period is 10 ms. In the present study, a general rule that provides a reference for ejector design and selection was obtained through experiments.

In this paper, a new sparse transmitting and receiving array is designed to improve the joint angle and polarization parameter estimation performance for bistatic electromagnetic vector sensors Multiple-Input Multiple-Output radar. Firstly, large array aperture can be obtained with the aid of the sparse transmitting and receiving array. Then, an effective third-order tensor model is constructed in order to make full use of the multidimensional space-time characteristics of output data after matching filtering. And, the Parallel Factor trilinear alternating least square algorithm is proposed to deal with the constructed third-order tensor model, which can yield closed-form automatically paired two dimensional Direction of Departure and two dimensional Direction of Departure estimation without additional angle pair matching process. Furthermore, two sets of high accuracy rotation invariance relationships corresponding to transmit elevation angle and receive elevation angle can be achieved by using the estimated transmit steering vector matrix and receive steering vector matrix. After the accuracy transmit elevation angle and receive angle are obtained, the corresponding transmitting and receiving azimuth angle, polarization angle and polarization phase difference can be accurately estimated by using the vector-cross-product algorithm. Compared with existing algorithms, the proposed algorithm can avoid high dimensional eigenvalue decomposition and additional parameter matching process. Moreover, the high estimation performance of the proposed can be further guaranteed by using the designed sparse array. Finally, simulation results demonstrate the effectiveness and superiority of the proposed method in terms of estimation accuracy and angle resolution.

Study Design: This is secondary research examining the longitudinal mediation effect within a structural equation model. Objective: To identify possible mechanisms that mediate the effects of a cognitive behavioral approach upon disability and pain in low back pain patients. Summary of Background Data: Cognitive behavioral interventions (CBIs) can improve pain and disability in low back pain (LBP) but the mechanisms of action are unclear. We used data from a large randomized controlled trial to investigate mediators of the treatment effect of CBI. Methods: Pain self-efficacy, fear avoidance, and physical and mental functioning were selected as candidate mediators based on the theoretical rationale of the intervention. The primary treatment outcomes were the Roland Morris Questionnaire (RMDQ) and the modified Von Korff scale (MVK pain and disability) at 12 months. We used structural equation models to estimate the contribution of mediators. All models were tested for goodness-of-fit using χ2, Root Mean Square Error of Approximation, Adjusted Goodness of Fit Index, and Bentler Comparative Fit Index. Results: We included 701 adults with LBP. The average RMDQ score at baseline for those on the intervention arm was 8.8 (Standard Deviation 5.0). The intervention was effective in reducing disability and pain at 12 months. Change in mental functioning was not a significant mediator. Changes to pain self-efficacy, fear avoidance, and physical functioning were causal mediators of the treatment effect at 12 months (RMDQ b= –0.149, P < 0.001; MVK-pain b = –0.181, P < 0.001 and MVK-disability b = –0.180, P < 0.001). Overall, the SEM model exceeded the threshold for acceptable goodness-of-fit. Conclusion: Fear avoidance and self-efficacy were important causal mediators of the cognitive behavioral treatment effect. Self-assessed change in physical function was a causal mediator but mental functioning was not. This suggests people need to experience meaningful change in physical function and beliefs but not in mental functioning associated with LBP, to achieve a treatment benefit.

The electrochemical oxidation of thiourea in phosphate-buffered solution (PBS, pH 6.0) was studied, and it was shown in the cyclic voltammogram that sulfate addition results in the appearance of a new current peak at ∼0.90 V versus RHE (reversible hydrogen electrode), indicating that the sulfate is chemisorbed. Both current and potential oscillations were observed during the electrochemical oxidation of thiourea in the presence of sulfate under potentiostatic and galvanostatic control, respectively. Potential oscillations occurred in two regions of linear current sweep voltammetry. The presence of adsorbed sulfate gives rise to negative differential resistance (NDR) for the positive feedback of oscillations in the first oscillation region. The bursting and period-doubling oscillations in the second region are caused by oxide formation and adsorbed sulfate acting simultaneously as positive feedbacks. A similar chemisorbed sulfate layer was previously observed with scanning tunneling microscopy and surface ...

We report a novel interpenetrating three-dimentional (3D) macroporous graphene aerogels (GAs) composite consisting of MnO2 wrapping for potential supercapacitor applications. In this article, the macroporous GAs holds abundant of interconnected macroporous and has excellent intrinsic high electrical conductivity resulting from the graphene. Therefore, employing the GAs as the substrates to combine with MnO2 will exhibit excellent electronic conductivity and effective ion-transport capability. The 3D macroporous MnO2/GAs composite has a specific capacitance of 200 F g-1. Thus, the corresponding 3D porous hierarchical GAs/MnO2 materials have a great potential to be used in the field of supercapacitors. This strategy could also be used for other materials to improve the performance of supercapacitors.

We report a direct, modulated bandwidth enhancement in a amplified feedback laser (AFL), both experimentally and numerically. By means of fabricated devices, an enhanced ?3??dB bandwidth of 27 GHz with an in-band flatness of ±3??dB is experimentally confirmed at 13?°C. It is numerically confirmed that the modulated bandwidth of the AFL can be enhanced to two times its original bandwidth, with more controlled flexibility to realize a flat, small-signal response.

We report a novel high-power bistable distributed feedback (DFB) semiconductor laser diode operating near 1060 nm, which is realized by inserting a high-bandgap electron barrier layer and a grating layer in a super large optical cavity laser design. Optical and electrical bistable characteristics are both observed for this device. An on-state optical output power of 98 mW and an on-off extinction ratio of 22 dB were demonstrated between the bistable states. A qualitative physical model based on carrier population profile shift is used to explain the switching effect. Optical flip-flop operation was also demonstrated.

We report the fabrication of multi-wavelength DFB laser arrays operating around 1.3 μm using a novel MOCVD based selective area growth approach. We show that the DFB laser wavelength can be precisely tuned by adjusting key design parameters including the oxide mask strip width and separation. Stable-single-mode DFB laser array operations are demonstrated with side mode suppression ratio >35 dB and the wavelength span of DFB laser array can arrive at 13.9 nm through optimizing the design parameters. Our process represents a simple and cost effective solution for applications requiring multi-wavelength laser sources covering a wide wavelength span, such as silicon photonic light sources in next generation 100 G Gigabit Ethernet optical systems.

We demonstrate the modulation bandwidth enhancement in integrated coupled DFB lasers. The coupling strength of the dual DFB is tunable duo to a SOA sandwiching in the center. The 3-dB bandwidth is increased from 8.6 GHz to 18.7 GHz under mutual injection locking.

We report the second harmonic generation frequency-resolved optical gating (SHG-FROG) measurements on a monolithically integrated multichannel mode-locked semiconductor laser based on arrayed waveguide grating. Clear phase correlation between synchronized mode-locked channels was demonstrated.

We present preliminary results on a widely-tunable laser with monolithically integrated high-Q ring based on heterogeneous silicon integration platform. The laser exhibits > 43 nm tuning range with side mode suppression ratio larger than 40 dB in the O-band.