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Solar energy, wind energy etc. are the main sustainable energy sources used around the world. These sustainable energy sources are used in day-to-day life in various forms for numerous purposes. One of the highly used sustainable energy sources is the solar energy which with the help of photovoltaic (PV) cells can be made use for the generation of electrical power. However, these sources generate less voltage values and thus it requires a high gain converter. In this paper, a modified Luo with flyback DC to DC converter is presented that assures high voltage gain, single switch, less stress across the components and less ripple current. Furthermore, the simulations along with the hardware prototype for the presented converter is carried out and presented in this paper.

A 76-year-old man was admitted to the hospital with acute onset of involuntary movements of the left side of his body. His neurological examination revealed he was oriented only to himself, and aforementioned movements of his left arm and leg. CT head demonstrated old infarcts in his right aspect of his pons and basal ganglia. Cerebrospinal fluid analysis was unremarkable. He initially had a normal blood glucose with an elevated anion gap and elevated creatine kinase. Brain MRI showed a small lacunar-type ischaemic infarct within the anteromedial aspect of the right cerebral peduncle, which localised to his haemiballism. To prevent worsening rhabdomyolysis associated with his haemiballism, the primary team initiated both tetrabenazine and diazepam. His movements improved after 1 week of medication therapy. This report discusses a thorough workup for this movement disorder and when to intervene for this distressing condition.

Objectives: We examined whether preadmission history of depression is associated with less delirium/coma-free (DCF) days, worse 1-year depression severity and cognitive impairment. Design and measurements: A health proxy reported history of depression. Separate models examined the effect of preadmission history of depression on: (a) intensive care unit (ICU) course, measured as DCF days; (b) depression symptom severity at 3 and 12 months, measured by the Beck Depression Inventory-II (BDI-II); and (c) cognitive performance at 3 and 12 months, measured by the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) global score. Setting and participants: Patients admitted to the medical/surgical ICU services were eligible. Results: Of 821 subjects eligible at enrollment, 261 (33%) had preadmission history of depression. After adjusting for covariates, preadmission history of depression was not associated with less DCF days (OR 0.78, 95% CI, 0.59–1.03 p = 0.077). A prior history of depression was associated with higher BDI-II scores at 3 and 12 months (3 months OR 2.15, 95% CI, 1.42–3.24 p = p = 0.003). We did not observe an association between preadmission history of depression and cognitive performance at either 3 or 12 months (3 months beta coefficient −0.04, 95% CI, −2.70–2.62 p = 0.97; 12 months 1.5, 95% CI, −1.26–4.26 p = 0.28). Conclusion: Patients with a depression history prior to ICU stay exhibit a greater severity of depressive symptoms in the year after hospitalization.

Background Surgical approaches to the third ventricle (TV) have always represented a technical challenge in neurosurgery. Virtual reality (VR) is attaining increasing relevance in training programs and preoperative planning. The aim of this study is to demonstrate the worthwhile mutual contribution of VR simulations and specimen dissections to develop a new surgical approach to the TV. Methods The transcortical endoportal subchoroidal endoscope-assisted (TEPSEA) approach was planned and simulated thanks to VR (Surgical Theater©, LLC, Cleveland, Ohio), and then implemented on cadaver specimens by using the VBAS portal system (Viewsite™ Brain Access System TC Model, Vycor Medical™ Inc). We assessed anthropometric measurements during VR planning and evaluated surgical operability during anatomical dissections. Results Surgical field depths measured between 75.6 and 85.3 mm to mammillary bodies and habenular commissure, which were in mean 20.2 mm away. An 18-mm movement was estimated for 15°-posterior tilting of a 70-mm long VBAS. Excellent exposure and maneuverability were achieved within the TV through a 2.47 cm2 portal working area. The 30°-endoscope assistance expanded the access towards the anterior and posterior walls of the TV particularly to the infundibular recess, mammillary bodies, habenular commissure and pineal recess. Conclusions We documented the utility of a step-by-step VR planning and simulation followed by anatomical dissections to study surgical approaches to deep brain areas. The TEPSEA exploits the portal system and endoscopic assistance to access the entire TV minimizing cortical and white matter manipulation.

Operating CMOS circuits at cryogenic temperatures offers advantages of higher mobility, higher ON-current, and better subthreshold characteristics, which can be leveraged to realize high-performance CMOS circuits. However, an ultra-low-voltage operation is necessary to minimize the power consumption and to offset the cooling cost overheads. The MOSFET threshold voltages (Vt) increase at cryogenic temperatures making it challenging to achieve high performance while operating at very low voltage. Ultra-thin body and buried oxide silicon-on-insulator (UTBB-SOI)-based MOSFETs can modulate the transistor threshold voltage using the back-gate bias, unlike conventional FinFETs. This unique UTBB-SOI technology attribute has been leveraged to realize compact pseudo-static storage circuits, namely, embedded dynamic random access memory (DRAM) bitcell and a flip-flop operating at 0.2 V and 77 K. This article presents UTBB-SOI device fabrication details and calibrate experimental device characteristics with BSIM compact models. SPICE simulations suggest the feasibility of three-transistor gain-cell embedded DRAM (eDRAM) capable of reliably storing three distinct voltage levels (1.5 bits/cell) and exhibiting retention time of the order of 104 s. Furthermore, a unique pseudo-static flip-flop design is presented, which can lower the clock power by 50%, transistor count by 20%, and static power consumption by 20%.

Background In patients with heart failure with reduced ejection fraction (HFrEF) and hypertension, systolic blood pressure is recommended to be maintained below 130 mmHg, although this has not been shown to be associated with improved outcomes. We examined the association of anti-hypertensive drug initiation and outcomes in patients with HFrEF. Methods In the Medicare-linked OPTIMIZE-HF, 7966 patients with HFrEF (ejection fraction ≤40%) without renal failure were not receiving anti-hypertensive drugs before hospitalization, of whom 692 received discharge prescriptions for those drugs (thiazides and calcium channel blockers). We assembled a propensity score-matched cohort of 687 pairs of patients initiated and not initiated on anti-hypertensive drugs, balanced on 38 baseline characteristics. Hazard ratios (HR) and 95% confidence intervals (CI) for outcomes associated with anti-hypertensive drug initiation were estimated in matched cohort. Results Matched patients (n=1374) had a mean age of 74 years, 41% were women, 17% were African American, 66% were discharged on renin-angiotensin system inhibitors and beta blockers, and 10% on aldosterone antagonists. During 6 (median 2.5) years of follow-up, 70% of the patients died and 53% had heart failure readmission. Anti-hypertensive drug initiation was not significantly associated with all-cause mortality (HR, 0.95; 95% CI, 0.83–1.07) or heart failure readmission (HR, 0.93; 95% CI, 0.80–1.07). Similar associations were observed during 30 days and 12 months of follow-up. Conclusions Among hospitalized older patients with HFrEF receiving contemporary treatments for heart failure, initiation of an anti-hypertensive drug was not associated with a lower risk of all-cause mortality or hospital readmission.

Although preoperative immunotherapy is increasingly utilized for non-small cell lung cancer, there remains a paucity of robust clinical data on its safety and long-term survival. Our objective was to evaluate the perioperative outcomes and survival associated with immunotherapy followed by surgery for patients with non-small cell lung cancer.Outcomes of patients with non-small cell lung cancer who underwent lung resection after preoperative chemotherapy with or without radiation or immunotherapy (with or without chemotherapy or chemoradiation) in the National Cancer Database (2010 to 2017) were evaluated using Kaplan-Meier analysis, multivariable logistic regression, multivariable Cox proportional hazards analysis, and propensity score-matched analysis.From 2010 to 2017, 236 patients (2.2%) received immunotherapy and 10 715 patients received preoperative chemotherapy followed by surgery. There were no significant differences between the immunotherapy and preoperative chemotherapy groups with regard to margin positivity (8.5% [n = 20] vs 7.5% [n = 715], P = .98), 30-day readmission (4.2% [n = 10] vs 4.1% [n = 440], P = .87), and 30-day mortality (0.4% [n = 1] vs 2.4% [n = 253], P = .25). The immunotherapy and preoperative chemotherapy groups had similar overall survival (5-year survival 63% [95% confidence interval, 50% to 74%] vs 51% [95% confidence interval, 50% to 52%], log rank P = .06; multivariable adjusted hazard ratio 0.98; 95% confidence interval, 0.67 to 1.41; P = .90). A propensity score matched analysis of 344 patients, well matched by preoperative characteristics, showed no significant differences in short-term outcomes and overall survival (log rank P = 1.00) between the two groups.In this national analysis, preoperative immunotherapy followed by surgery for non-small cell lung cancer was found to be safe and feasible with similar short-term outcomes and overall survival when compared with preoperative chemotherapy followed by surgery.

Background During the COVID-19 pandemic, patients with lung cancer may experience treatment delays. The objective of this study was to evaluate the impact of extended treatment delays on survival among patients with stage I typical bronchopulmonary carcinoid (BC), lepidic predominant adenocarcinoma (LPA) or invasive adenocarcinoma with a lepidic component (ADL). Methods Using National Cancer Database data (2004-2015), multivariable Cox regression analysis with penalized smoothing splines was performed to examine the association between treatment delay and all-cause mortality for stage I BC, LPA, and ADL. Propensity score–matched analyses compared the overall survival of patients who received “early” vs “delayed” surgery (ie, 0-30 vs 90-120 days after diagnosis) across the different histologic subtypes. Results During the study period, patients with stage I BC (n = 4947), LPA (n = 5340), and ADL (n = 6816) underwent surgery. Cox regression analysis of these cohorts showed a gradual steady increase in the hazard ratio the longer treatment is delayed. However, in propensity score–matched analyses that created cohorts of patients who underwent early and delayed surgery that were well-balanced in patient characteristics, no significant differences in 5-year survival were found between early and delayed surgery for stage I BC (87% [95% CI:77%-93%] vs 89% [95% CI: 80%-94%]), stage I LPA (73% [95% CI: 64%-80%] vs 77% [95% CI: 68%-83%]), and stage I ADL (71% [95% CI: 64%-76%] vs 69% [95% CI: 60%-76%]). Conclusions During the COVID-19 pandemic, for early-stage indolent lung tumors and part-solid ground glass lung nodules, a delay of surgery by 3-4 months after diagnosis can be considered.

BACKGROUND: Improved understanding of the pathways associated with airway pathophysiologic features in COPD will identify new predictive biomarkers and novel therapeutic targets. RESEARCH QUESTION: Which physiologic pathways are altered in the airways of patients with COPD and will predict exacerbations? STUDY DESIGN AND METHODS: We applied a mass spectrometric panel of metabolomic biomarkers related to mucus hydration and inflammation to sputa from the multicenter Subpopulations and Intermediate Outcome Measures in COPD Study. Biomarkers elevated in sputa from patients with COPD were evaluated for relationships to measures of COPD disease severity and their ability to predict future exacerbations. RESULTS: Sputum supernatants from 980 patients were analyzed: 77 healthy nonsmokers, 341 smokers with preserved spirometry, and 562 patients with COPD (178 with Global Initiative on Chronic Obstructive Lung Disease [GOLD] stage 1 disease, 303 with GOLD stage 2 disease, and 81 with GOLD stage 3 disease) were analyzed. Biomarkers from multiple pathways were elevated in COPD and correlated with sputum neutrophil counts. Among the most significant analytes (false discovery rate, 0.1) were sialic acid, hypoxanthine, xanthine, methylthioadenosine, adenine, and glutathione. Sialic acid and hypoxanthine were associated strongly with measures of disease severity, and elevation of these biomarkers was associated with shorter time to exacerbation and improved prediction models of future exacerbations. INTERPRETATION: Biomarker evaluation implicated pathways involved in mucus hydration, adenosine metabolism, methionine salvage, and oxidative stress in COPD airway pathophysiologic characteristics. Therapies that target these pathways may be of benefit in COPD, and a simple model adding sputum-soluble phase biomarkers improves prediction of pulmonary exacerbations. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT01969344; URL: www.clinicaltrials.gov

Background The effects of integrated yoga programs on mental health outcomes in inflammatory bowel disease (IBD) have not been well explored. To explore the acceptability, implementation and effectiveness of an integrated eight-week yoga program plus aromatherapy massage in patients with IBD. Methods Nine participants with documented IBD were recruited from a gastroenterology clinic in Calgary, Alberta, Canada to participate in an integrated yoga program weekly for eight weeks with outcomes assessed at baseline and week 8. Primary outcomes were assessed using Theory of Planned Behaviour as a guiding theory to identify salient beliefs from qualitative analysis of a semi-structured interview, survey items measuring the strength of beliefs and a daily log was used to capture adherence and adverse events. Secondary outcomes were collected using validated survey tools examining anxiety, depression, stress, sleep quality, and physical and mental quality of life. Results Attitude, subjective norm and perceived behavioral control beliefs pertinent to the yoga intervention and daily practice were identified. Participants reported feeling the intervention was very helpful; however, felt guilt about not completing daily practices which decreased confidence and intention to continue with the practice. An average of 55.6% of in-person sessions were attended and decreased over time. Participants practiced on average of 5.4 days per week. Depression and mental health scores improved at week 8 from baseline. Conclusions We were able to identify key salient beliefs of IBD patients in regard to an integrated yoga plus aromatherapy massage intervention. This intervention appears to be acceptable and further research should explore its potential to improve mental and physical health outcomes including IBD symptoms.

Cirrhosis is the terminal stage of progressive liver fibrosis, affecting 1%-2% of the global population and accounting for 1.3 million deaths annually.1,2 Median survival for persons with compensated cirrhosis is approximately 12 years, compared with only 2 years for those with hepatic decompensation. Accurate prediction of hepatic decompensation is an unmet need to enable identification of patients with cirrhosis who could benefit from close monitoring and timely medical interventions. Besides, risk stratification of patients with cirrhosis could help inform patient selection for trials evaluating therapies to prevent hepatic decompensation. Although various clinical scores, such as the albumin-bilirubin (ALBI) and fibrosis-4 (FIB-4) indices (ALBI-FIB4 score) have been proposed to predict long-term risk of hepatic decompensation,3 external validation has often shown suboptimal prognostic capability and revealed room for improvement.4.

Age estimation models can be employed in many applications, including soft biometrics, content access control, targeted advertising, and many more. However, as some facial images are taken in unrestrained conditions, the quality relegates, which results in the loss of several essential ageing features. This study investigates how introducing a new layer of data processing based on a super-resolution generative adversarial network (SRGAN) model can influence the accuracy of age estimation by enhancing the quality of both the training and testing samples. Additionally, we introduce a novel convolutional neural network (CNN) classifier to distinguish between several age classes. We train one of our classifiers on a reconstructed version of the original dataset and compare its performance with an identical classifier trained on the original version of the same dataset. Our findings reveal that the classifier which trains on the reconstructed dataset produces better classification accuracy, opening the door for more research into building data-centric machine learning systems.

OBJECTIVE There is a reported elevated risk of cerebral aneurysms in patients with intracranial dural arteriovenous fistulas (dAVFs). However, the natural history, rate of spontaneous regression, and ideal treatment regimen are not well characterized. In this study, the authors aimed to describe the characteristics of patients with dAVFs and intracranial aneurysms and propose a classification system. METHODS The Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR) database from 12 centers was retrospectively reviewed. Analysis was performed to compare dAVF patients with (dAVF+ cohort) and without (dAVF-only cohort) concomitant aneurysm. Aneurysms were categorized based on location as a dAVF flow-related aneurysm (FRA) or a dAVF non–flow-related aneurysm (NFRA), with further classification as extra- or intradural. Patients with traumatic pseudoaneurysms or aneurysms with associated arteriovenous malformations were excluded from the analysis. Patient demographics, dAVF anatomical information, aneurysm information, and follow-up data were collected. RESULTS Of the 1077 patients, 1043 were eligible for inclusion, comprising 978 (93.8%) and 65 (6.2%) in the dAVF-only and dAVF+ cohorts, respectively. There were 96 aneurysms in the dAVF+ cohort; 10 patients (1%) harbored 12 FRAs, and 55 patients (5.3%) harbored 84 NFRAs. Dural AVF+ patients had higher rates of smoking (59.3% vs 35.2%, p < 0.001) and illicit drug use (5.8% vs 1.5%, p = 0.02). Sixteen dAVF+ patients (24.6%) presented with aneurysm rupture, which represented 16.7% of the total aneurysms. One patient (1.5%) had aneurysm rupture during follow-up. Patients with dAVF+ were more likely to have a dAVF located in nonconventional locations, less likely to have arterial supply to the dAVF from external carotid artery branches, and more likely to have supply from pial branches. Rates of cortical venous drainage and Borden type distributions were comparable between cohorts. A minority (12.5%) of aneurysms were FRAs. The majority of the aneurysms underwent treatment via either endovascular (36.5%) or microsurgical (15.6%) technique. A small proportion of aneurysms managed conservatively either with or without dAVF treatment spontaneously regressed (6.2%). CONCLUSIONS Patients with dAVF have a similar risk of harboring a concomitant intracranial aneurysm unrelated to the dAVF (5.3%) compared with the general population (approximately 2%–5%) and a rare risk (0.9%) of harboring an FRA. Only 50% of FRAs are intradural. Dural AVF+ patients have differences in dAVF angioarchitecture. A subset of dAVF+ patients harbor FRAs that may regress after dAVF treatment.

As compute demands and their large energy costs continue to rise in the datacenter, it is imperative to identify low energy compute solutions. One approach is to investigate device schemes based on collective mode phenomena arising at low temperatures where power dissipation and switching voltage can be extremely low. Additionally, such devices could also have applications in quantum computing where such a low power logic/memory scheme could possibly be integrated onto the qubit plane, which is typically at ∼10 mK temperature. Josephson Junction Field Effect Transistor (JJFET) is a promising candidate for low power operation with zero voltage drop across its drain-source terminals while operating in the superconducting regime. JJFET logic gate is typically realized as a n-type JJFET connected in a common-source configuration with a current source load. This results in high noise margin for logic-1 input but not for both logic-1 and 0. In this paper, we propose an overdamped region, n-type JJFET based digital logic using a cascaded common-source configuration-based design yielding high noise margin for both the logic inputs. DC noise margin sensitivity analysis is performed for the bias current and threshold voltage modulation. The noise margin can be further improved (approaches ideal inverter case) by cascading multiple common source stages yielding higher inverter gain.

Background Intravenous fluid therapy represents the most common intervention critically ill patients are exposed to. Hyperchloremia and metabolic acidosis associated with 0.9% sodium chloride have been observed to lead to worse outcomes, including mortality. Balanced solutions, such as Plasma-Lyte 148 and Compound Sodium Lactate, represent potential alternatives but the evidence on optimal fluid choices in critically ill children remains scarce. This study aims to demonstrate whether balanced solutions, when used as intravenous fluid therapy, are able to reduce the incidence of a rise in serum chloride level compared to 0.9% sodium chloride in critically ill children. Methods This is a single-centre, open-label randomized controlled trial with parallel 1:1:1 assignment into three groups: 0.9% sodium chloride, Plasma-Lyte 148, and Compound Sodium Lactate solutions for intravenous fluid therapy. The intervention includes both maintenance and bolus fluid therapy. Children aged < 16 years admitted to intensive care and receiving intravenous fluid therapy during the first 4 h of admission are eligible. The primary outcome measure is a ≥ 5mmol/L increase in serum chloride level within 48 h post-randomization. The enrolment target is 480 patients. The main analyses will be intention-to-treat. Discussion This study tests three types of intravenous fluid therapy in order to compare the risk of hyperchloremia associated with normal saline versus balanced solutions. This pragmatic study is thereby assessing the most common intervention in paediatric critical care. This is a single-centre open-label study with no blinding at the level of delivery of the intervention. Certain paediatric intensive care unit (PICU) patient groups such as those admitted with a cardiac condition or following a traumatic brain injury are excluded from this study. Trial registration The study has received ethical approval (HREC/19/QCHQ/53177: 06/06/2019). It is registered in the Australian New Zealand Clinical Trials Registry (ACTRN12619001244190) from 9th September 2019. Recruitment commenced on 12th November 2019. The primary results manuscript will be published in a peer-reviewed journal.

Kidney-sparing procedures for upper tract urothelial carcinoma (UTUC) have evolved from imperative to elective indications for management of low-risk disease. Ureterorenoscopy is the most common procedure for the diagnosis, treatment, and surveillance of UTUC. A notable consideration following ureterorenoscopy is the higher risk of downstream bladder seeding. Here we review the importance of and scientific evidence for chemoprophylaxis after ureterorenoscopy. PATIENT SUMMARY: For patients with low-risk cancer of the upper urinary tract, a procedure called ureterorenoscopy (URS) involving insertion of a thin telescope through the ureter and into the kidney is increasingly used for biopsy. URS increases the risk of cancer seeding in the bladder. We review evidence on the benefit of prophylactic bladder chemotherapy after URS.

Purpose Higher energy (>6 MV) photons reduce dose inhomogeneity with breast tangent beams, thereby reducing late breast toxicity, but skin and superficial tissue sparing by higher energy beams raises concerns about local recurrence (LR) risk. This study aimed to determine whether beam energy and surgical bed-to-skin distance affect LR. Methods and Materials This population-based study included newly diagnosed invasive breast cancers without skin involvement (pT1-4a, any-N, M0) treated with breast-conserving surgery and adjuvant whole breast radiotherapy without bolus or beam spoilers. The primary endpoint was the cumulative incidence of LR (CILR). A multivariable analysis (MVA) included mean beam energy, age, T-stage, nodal status, overall stage, lymphovascular invasion (LVI), grade, margin status, extensive intraductal component (EIC), breast cancer subtype, hormone therapy and chemotherapy. In a subgroup with contoured surgical beds, another MVA included surgical bed-to-skin distance. Results The cohort consisted of 10,083 women treated from 2002 to 2011, 327 with 4MV, 6,006 with 6 MV, 2,083 with >6-10 MV and 1,667 with >10 MV tangents. The median follow-up time was 11.1 years. The 10-year CILR was 3.1% [95% confidence interval 1.6,5.4] with 4 MV, 2.8% [2.4,3.3] with 6 MV, 4.2% [3.4,5.3] with >6-10 MV and 2.6% [1.9,3.5] with >10 MV. On MVA of the entire cohort, LR risk was increased with positive margins, LVI, EIC, and lack of hormone therapy, but was not associated with beam energy (HR = 1.01 [0.96,1.05], p = 0.8). On MVA of 3,359 patients with contoured surgical beds, LR risk was not associated with surgical bed-to-skin distance (HR = 1.00 [0.99,1.02], p = 0.8). Conclusions Use of higher breast tangent beam energies is not associated with increased risk of local recurrence, including in cases with surgical beds that are close to the skin.

Severe alcoholic hepatitis (AH) is a highly lethal condition and it is still a challenge to predict the outcome. We previously identified and validated a composite score of hepatic 123-gene prognostic signature and the model for end-stage liver disease (MELD) score: gene signature-MELD. However, the need for liver biopsy limits its clinical application. Therefore, we aimed to identify a plasma protein-based surrogate of the gene signature and independently validate its prognostic capability.All patients were diagnosed with severe AH at Cliniques universitaires de Bruxelles Hôpital Erasme (Brussels, Belgium), and the plasma samples were collected at admission before any treatment. The primary outcome was death or liver transplantation within 90 days. Using our computational pipeline, named translation of tissue expression to secretome (TexSEC), a hepatic-transcriptome-based prognostic signature was converted to a plasma-based secretome signature, which was optimized in 50 patients by comparing their hepatic molecular dysregulation status and combining it with the MELD score. The composite score was validated independently in 57 patients.The TexSEC and optimization process identified a 6-plasma-protein panel as a surrogate for the 123-gene signature. A composite score with the MELD score, the plasma-signature (ps)-MELD score, was created by using the coefficients of the gene signature-MELD equation. In the validation cohort, the high-risk ps-MELD (n = 23; 40%) was associated significantly with death or liver transplantation within 90 days (adjusted hazard ratio, 4.57; 95% CI, 2.15-9.30; P.001). The ps-MELD score showed a stable, high prognostic association (time-dependent area under receiver operating characteristics curve,0.80) and was well calibrated over time; it consistently outperformed existing clinical scores as indicated by various model performance indices.The high-risk ps-MELD score was associated with short-term survival in patients with severe AH.

Electric grids are seeing increasing adoption of renewables interfaced with power electronics. As the share of renewable generation increases, the inverters are expected to operate in grid-forming mode to replace large conventional synchronous generation. Further, in geographical islands and isolated/rural areas, inverters interfacing renewable generators and storage are used to form the grids and share the loads. Given the expected presence of grid-forming inverters in future power systems, there is an urgent need to revise education curricula about the stability issues arising from these interconnected inverters. Existing training is overly reliant on numerical simulation or on expensive tools such as real-time simulators. In this paper, we present a laboratory hands-on project dealing with small-signal stability in droop-controlled inverters. It entails simulation and hands-on experimentation for which an inexpensive microgrid set up was developed in-house at the National University of Singapore. The design project can be integrated into power engineering courses offered to senior and postgraduate students.

Endoscopic resection (ER) is the preferred treatment for superficial esophageal cancer; however, a safe time frame for performing ER has not been established. This study evaluated the period in which ER can be performed for patients with stage I esophageal adenocarcinoma without compromising outcomes.The 2004-2015 National Cancer Database was used to identify patients with cT1 N0 M0 esophageal adenocarcinoma who underwent upfront ER. The primary outcome was overall survival, which was evaluated using Kaplan-Meier and multivariable Cox proportional hazards methods. The secondary outcome was rate of margin-positive resection, which was evaluated using a multivariable logistic regression.A total of 983 patients met study criteria. The median time from diagnosis to ER was 34 days (interquartile range, 5-70 days). Patients in the highest quartile of time to ER were more likely to be treated at a high-volume center and at a center different from that of diagnosis compared with those in the lowest quartile. Increasing time to ER was not independently associated with survival (adjusted hazard ratio per 10 days, 1.02; 95% confidence interval, 0.98-1.05; P = .32) or margin-positive resection (odds ratio per 10 days 1.01; 95% confidence interval, 0.96-1.06; P = .60).In this National Cancer Database analysis, increasing time to endoscopic resection, up to 180 days from diagnosis, was not associated with worsened survival or increased odds of margin-positive resection in patients with cT1 N0 M0 esophageal adenocarcinoma. Given these findings, patients may be afforded time to be seen in specialty centers without risk of tumor progression.

Rationale: Individuals with Chronic Obstructive Pulmonary Disease (COPD) have a high prevalence of depression, which is associated with increased COPD hospitalizations and readmissions. Objectives:...

Background Previous studies suggest that prone positioning can increase PaO2/FiO2 and reduce mortality in moderate to severe acute respiratory distress syndrome. Effect of prone positioning and high flow nasal oxygen has been studied individually in COVID-19 patients but their combined effect on patient's outcome is yet to be reported. Methods In this study 120 severe COVID-19 positive patients were included and placed in awake prone positioning with high flow nasal oxygen. The efficacy in improving oxygenation with prone positioning and high flow nasal oxygen were evaluated by blood gas analysis. The primary outcome was a proportion of patients requiring non-invasive ventilation or invasive ventilation. The secondary outcomes were a comparison of arterial blood gas parameters and biochemical inflammatory parameters pre proning, end of first proning and end of last prone position in these patients. Results We found only 35 patients (34.3%) required the need for non-invasive or invasive mechanical ventilation support whereas 67 patients (65.7%) were managed successfully on high flow nasal oxygen along with awake prone positioning (p = 0.001). We found there were statistically significant improvements in arterial blood gas parameters and biochemical inflammatory markers after the end of last prone positioning with high flow nasal oxygen. Conclusions Early application of prone positioning in combination with high flow nasal oxygen may help in avoiding mechanical ventilation by improving oxygenation and biochemical inflammatory markers.

Introduction: Probiotics, including lactobacilli, have immunomodulatory activities with promising effects on inflammatory diseases. In this study, we evaluate the effect of Enterococcus durans (Edu) and three various strains of lactobacilli (Lacto-mix), including L. rhamnosus, L. casei, and L. plantarum, to prevent Experimental Autoimmune Encephalomyelitis (EAE) features Methods: C57BL/6 female mice were inoculated with Myelin Oigodendrocyte Glycoprotein (MOG35-55) in CFA (complete Freund’s adjuvant) to induce EAE. Five groups (n=6 in each group) of animals received saline or probiotics by oral gavage with 200 µL of lactobacilli (1.5×108 CFU/mL) for 2 weeks before the immunization and during the test for one month. Results: Histopathological studies showed an increase in infiltration of inflammatory cells and destruction of the myelin membrane in the EAE group but a decrease in inflammatory cells in the probiotic-treated animals. Pro-inflammatory cytokines (Interleukin [IL]-17 and Interferon [IFN]-γ) concentration in the supernatant of the brain and spinal cord tissues showed a significant increase in the EAE compared with the normal saline group (P

Friction stir welding (FSW) is a new solid-state welding technique used to join similar and dissimilar materials, especially aluminium alloys. Friction stir (FS) welding proposes numerous benefits compared to conventional fusion welding techniques and can be successfully applied in shipbuilding, aerospace, automobile, and railway industries. This paper gives a comprehensive review of the FSW process and its technical aspects. The effects of tool pin profiles, feed rate, tool tilt angle and welding speed, etc., and mechanical and metallurgical behavior of FS welded joints have been reviewed in this article. In addition, this paper covers the literature review of friction stir welding of similar and dissimilar aluminum alloys (AA), optimization techniques, welding defects, and fatigue behavior of FS welded joints. Furthermore, a summarized report of work done by many researchers in friction stir welding is also presented. Finally, it also identifies the future scope, applications, and research gap.

Background: Paediatric tumours are often characterised by the presence of recurrent DNA copy number alterations (CNAs). These DNA copy number profiles, obtained from a tissue biopsy, can aid in the correct prognostic classification and therapeutic stratification of several paediatric cancer entities (e.g. MYCN amplification in neuroblastoma) and are part of the routine diagnostic practice. Liquid biopsies (LQBs) offer a potentially safer alternative for such invasive tumour tissue biopsies and can provide deeper insight into tumour heterogeneity. Procedure: The robustness and reliability of LQB CNA analyses was evaluated. We performed retrospective CNA profiling using shallow whole-genome sequencing (sWGS) on paired plasma circulating cell-free DNA (cfDNA) and tissue DNA samples from routinely collected samples from paediatric patients (n = 128) representing different tumour entities, including osteosarcoma, Ewing sarcoma, rhabdomyosarcoma, Wilms tumour, brain tumours and neuroblastoma. Results: Overall, we observed a good concordance between CNAs in tissue DNA and cfDNA. The main cause of CNA discordance was found to be low cfDNA sample quality (i.e. the ratio of cfDNA (700 bp)). Furthermore, CNAs were observed that were present in cfDNA and not in tissue DNA, or vice-versa. In neuroblastoma samples, no false-positives or false-negatives were identified for the detection of the prognostic marker MYCN amplification. Conclusion: In future prospective studies, CNA analysis on LQBs that are of sufficient quality can serve as a complementary assay for CNA analysis on tissue biopsies, as either cfDNA or tissue DNA can contain CNAs that cannot be identified in the other biomaterial.

Chemical energy is not effectively converted into mechanical energy by an internal combustion engine. Major portion of heat energy get dissipated with exhaust and coolant. Use of thermoelectric generator (TEG) technology is regarded as an environment friendly technique for recovering the waste heat, with which heat energy directly converts into electrical energy. In this study, an experiment is conducted in which TEG technology has been used to recover waste heat going out through exhaust gas from the diesel engine. Thermoelectric modules were fixed on the surface of stainless steel made pipe having square cross-section. It has been found that the power output of thermoelectric generator enhances with the increase in engine load. The maximum electrical power output of TEG has been obtained as 37 W at maximum load of 6 kg. Overall thermal efficiency of diesel engine has also been improved with the use of TEG type of waste heat recovery system.

Background : The spread of duodenoscope-related infections has led to the recognition that reprocessing of duodenoscopes using high-level disinfection (HLD), if done perfectly, narrowly meets the advised thresholds of endoscope decontamination. In 2019, the US Food and Drug Administration (FDA) recommended a transition to duodenoscopes designed to pose less risk, including the use of disposable duodenoscopes. The EXALT Model-D™ single-use duodenoscope (EXALT) has been shown to be substantially equivalent to reusable duodenoscopes for clinical use. The objective of this study was to estimate the cost-effectiveness of EXALT in the United States Healthcare system. Methods : A cost-effectiveness model was developed comparing HLD, culture-and-quarantine (CQ), Ethylene oxide sterilization (ETO), and EXALT in a simulated cohort undergoing Endoscopic Retrograde Cholangiopancreatography (ERCP) for choledocholithiasis. Published information was leveraged describing clinical estimates, infectious outbreaks, and hospital costs. Results : In a base analysis, HLD was the least costly ($962), and EXALT was the costliest ($3,000), but yielded the most QALYs (0.0172 incremental QALYs). The incremental cost-effectiveness ratio was $38,461 for ETO gas sterilization and $62,185 for EXALT. However, with the availability of device-specific reimbursement for EXALT in the US in the form of transitional pass-through payment (TPT) and new technology add-on payment (NTAP), EXALT provided the highest cost-savings to the hospital versus alternative strategies by maintaining QALY gains while decreasing estimated net costs. Probabilistic sensitivity analyses showed EXALT to be preferred compared to HLD over a range of willingness-to-pay. Conclusion : EXALT is a viable and cost-effective strategy that should be strongly considered for ERCP.

Purpose Low-grade intermediate-risk nonmuscle-invasive bladder cancer (LG IR NMIBC) is a recurrent disease, thus requiring repeated transurethral resection of bladder tumor under general anesthesia. We evaluated the efficacy and safety of UGN-102, a mitomycin-containing reverse thermal gel, as a primary chemoablative therapeutic alternative to transurethral resection of bladder tumor for patients with LG IR NMIBC. Materials and methods This prospective, phase 2b, open-label, single-arm trial recruited patients with biopsy-proven LG IR NMIBC to receive 6 once-weekly instillations of UGN-102. The primary end point was complete response (CR) rate, defined as the proportion of patients with negative endoscopic examination, negative cytology and negative for-cause biopsy 3 months after treatment initiation. Patients with CR were followed quarterly up to 12 months to assess durability of treatment effect. Safety and adverse events were monitored throughout the trial. Results A total of 63 patients (38 males and 25 females 33-96 years old) enrolled and received ≥1 instillation of UGN-102. Among the patients 41 (65%) achieved CR at 3 months, of whom 39 (95%), 30 (73%) and 25 (61%) remained disease-free at 6, 9 and 12 months after treatment initiation, respectively. A total of 13 patients had documented recurrences. The probability of durable response 9 months after CR (12 months after treatment initiation) was estimated to be 73% by Kaplan-Meier analysis. Common adverse events (incidence ≥10%) included dysuria, urinary frequency, hematuria, micturition urgency, urinary tract infection and fatigue. Conclusions Nonsurgical primary chemoablation of LG IR NMIBC using UGN-102 resulted in significant treatment response with sustained durability. UGN-102 may provide an alternative to repetitive surgery for patients with LG IR NMIBC.

This study sought to determine whether stress cardiac magnetic resonance (CMR) provides clinically relevant risk reclassification in patients with known coronary artery disease (CAD) in a multicenter setting in the United States.Despite improvements in medical therapy and coronary revascularization, patients with previous CAD account for a disproportionately large portion of CV events and pose a challenge for noninvasive stress testing.From the Stress Perfusion Imaging in the United States (SPINS) registry, we identified consecutive patients with documented CAD who were referred to stress CMR for evaluation of myocardial ischemia. The primary outcome was nonfatal myocardial infarction (MI) or cardiovascular (CV) death. Major adverse CV events (MACE) included MI/CV death, hospitalization for heart failure or unstable angina, and late unplanned coronary artery bypass graft. The prognostic association and net reclassification improvement by ischemia for MI/CV death were determined.Out of 755 patients (age 64 ± 11 years, 64% male), we observed 97 MI/CV deaths and 210 MACE over a median follow-up of 5.3 years. Presence of ischemia demonstrated a significant association with MI/CV death (HR: 2.30; 95% CI: 1.54-3.44; P 0.001) and MACE (HR: 2.24 ([95% CI: 1.69-2.95; P0.001). In a multivariate model adjusted for CV risk factors, ischemia maintained strong association with MI/CV death (HR: 1.84; 95% CI: 1.17-2.88; P = 0.008) and MACE (HR: 1.77; 95% CI: 1.31-2.40; P 0.001) and reclassified 95% of patients at intermediate pretest risk (62% to low risk, 33% to high risk) with corresponding changes in the observed event rates of 1.4% and 5.3% per year for low and high post-test risk, respectively.In a multicenter cohort of patients with known CAD, CMR-assessed ischemia was strongly associated with MI/CV death and reclassified patient risk beyond CV risk factors, especially in those considered to be at intermediate risk. Absence of ischemia was associated with a2% annual rate of MI/CV death. (Stress CMR Perfusion Imaging in the United States [SPINS] Study; NCT03192891).

The active power consumption (APCm/c) of machine tools is generally the most significant electric parameter. Minimizing electrical energy and cutting emissions are both advantages of optimizing active power for machining operations. The active power consumption while drilling ST52.3 alloy steel was optimized under the present investigation. The influence of spindle rpm, feed rate, peck length, and drill point angle, as well as their interactions, were analyzed using Taguchi's L-27 design. The solid carbide drill was used in a drilling operation. The regression models were developed with RSM. Cutting parameters were held at lower levels, and drill point angle was retained at a greater level to get the minimum APCm/c values. According to the ANOVA results, the feed with a contribution of 61.85% emerged as one of the most critical cutting parameters for APCm/c. For APCm/c, the drill point angle seems to have no substantial impact, and the interactions between variables also affect little. Compared to industrial drilling parameters, there is a 15.19 percent improvement in APCm/c at the optimal levels of a drilling operation. The APCm/c regression model’s R square value is 99.11 percent, demonstrating the model's ability to make excellent predictions.

Problem definition: Operational disruptions can impact a firm’s risk, which manifests in a host of operational issues, including a higher holding cost for inventory, a higher financing cost for capacity expansion, and a higher perception of the firm’s risk among its supply chain partners. Academic/practical relevance: Although disruptions have been studied extensively in the operations management literature, the emphasis has been on mitigating the deleterious impact on the firm’s production potential rather than its risk. We examine whether implementing and credibly attesting to having effective internal control systems will meaningfully influence the impact of operational disruptions on the firm’s risk and market valuation. Methodology: We exploit a 2004 regulatory change that required certain firms to attest to having control systems in place. Our triple-difference regression specification takes advantage of a regulatory anomaly that excluded a well-defined set of firms from complying with the control system requirement. Results: We find that firms that were obligated to comply with this regulatory requirement experienced a materially smaller increase in their risk and a smaller decrease in their market value in the aftermath of an operational disruption. Firms that were not obligated to comply with this requirement did not experience such benefits in the aftermath of a disruption and instead, experienced a larger increase in their risk. Managerial implications: Fostering a better understanding of whether credible control systems can reduce the impact of disruptions on the firm’s risk and value is important as it identifies a broader set of mitigation strategies available to operations managers. This can help managers achieve a better fit between their risk mitigation initiatives and their objectives and budget constraints.