Load frequency stabilization of distinct hybrid conventional and renewable power systems incorporated with electrical vehicles and capacitive energy storage.

Maintaining a power balance between generation and demand is generally acknowledged as being essential to maintaining a system frequency within reasonable bounds. This is especially important for linked renewable-based hybrid power systems (HPS), where disruptions are more likely to occur. This paper suggests a prominent modified "Fractional order-proportional-integral with double derivative (FOPIDD2) controller" as an innovative HPS controller in order to navigate these obstacles. The recommended control approach has been validated in power systems including wind, reheat thermal, solar, and hydro generating, as well as capacitive energy storage and electric vehicle. The improved controller's performance is evaluated by comparing it to regular FOPID, PID, and PIDD2 controllers. Furthermore, the gains of the newly structured FOPIDD2 controller are optimized using a newly intended algorithm terms as squid game optimizer (SGO). The controller's performance is compared to benchmarks such as the grey wolf optimizer (GWO) and jellyfish search optimization. By comparing performance characteristics such as maximum frequency undershoot/overshoot, and steadying time, the SGO-FOPIDD2 controller outperforms the other techniques. The suggested SGO optimized FOPIDD2 controller was analyzed and validated for its ability to withstand the influence of power system parameter uncertainties under various loading scenarios and situations. Without any complicated design, the results show that the new controller can work steadily and regulate frequency with an appropriate controller coefficient.

Decision analysis in cardiac surgery: a scoping review and methodological primer.

OBJECTIVES: Randomized controlled trials are the gold standard for evidence generation in medicine but are limited by their real-world generalizability, resource needs, shorter follow-up durations and inability to be conducted for all clinical questions. Decision analysis (DA) models may simulate trials and observational studies by using existing data and evidence- and expert-informed assumptions and extend analyses over longer time horizons, different study populations and specific scenarios, helping to translate population outcomes to patient-specific clinical and economic outcomes. Here, we present a scoping review and methodological primer on DA for cardiac surgery research. METHODS: A scoping review was performed using the PubMed/MEDLINE, EMBASE and Web of Science databases for cardiac surgery DA studies published until December 2021. Articles were summarized descriptively to quantify trends and ascertain methodological consistency. RESULTS: A total of 184 articles were identified, among which Markov models (N = 92, 50.0%) were the most commonly used models. The most common outcomes were costs (N = 107, 58.2%), quality-adjusted life-years (N = 96, 52.2%) and incremental cost-effectiveness ratios (N = 89, 48.4%). Most (N = 165, 89.7%) articles applied sensitivity analyses, most frequently in the form of deterministic sensitivity analyses (N = 128, 69.6%). Reporting of guidelines to inform the model development and/or reporting was present in 22.3% of articles. CONCLUSION: DA methods are increasing but remain limited and highly variable in cardiac surgery. A methodological primer is presented and may provide researchers with the foundation to start with or improve DA, as well as provide readers and reviewers with the fundamental concepts to review DA studies.

Stabilization and tracking control of underactuated ball and beam system using metaheuristic optimization based TID-F and PIDD2-PI control schemes.

In this paper, we propose two different control strategies for the position control of the ball of the ball and beam system (BBS). The first control strategy uses the proportional integral derivative-second derivative with a proportional integrator PIDD2-PI. The second control strategy uses the tilt integral derivative with filter (TID-F). The designed controllers employ two distinct metaheuristic computation techniques: grey wolf optimization (GWO) and whale optimization algorithm (WOA) for the parameter tuning. We evaluated the dynamic and steady-state performance of the proposed control strategies using four performance indices. In addition, to analyze the robustness of proposed control strategies, a comprehensive comparison has been performed with a variety of controllers, including tilt integral-derivative (TID), fractional order proportional integral derivative (FOPID), integral-proportional derivative (I-PD), proportional integral-derivative (PI-D), and proportional integral proportional derivative (PI-PD). By comparing different test cases, including the variation in the parameters of the BBS with disturbance, we examine step response, set point tracking, disturbance rejection analysis, and robustness of proposed control strategies. The comprehensive comparison of results shows that WOA-PIDD2-PI-ISE and GWO-TID-F- ISE perform superior. Moreover, the proposed control strategies yield oscillation-free, stable, and quick response, which confirms the robustness of the proposed control strategies to the disturbance, parameter variation of BBS, and tracking performance. The practical implementation of the proposed controllers can be in the field of under actuated mechanical systems (UMS), robotics and industrial automation. The proposed control strategies are successfully tested in MATLAB simulation.

Barriers to Access to Cardiac Surgery: Canadian Situation and Global Context.

Cardiovascular disease is the leading cause of morbidity and mortality worldwide. Cardiovascular care spans primary, secondary, and tertiary prevention and care, whereby tertiary care is particularly prone to disparities in care. Challenges in access to care especially affect low- and middle-income countries (LMICs), however, multiple barriers also exist and persist across high-income countries. Canada is lauded for its universal health coverage but is faced with health care system challenges and substantial geographic barriers. Canada possesses 203 active cardiac surgeons, or 5.02 per million population, ranging from 3.70 per million in Newfoundland and Labrador to 7.48 in Nova Scotia. As such, Canada possesses fewer cardiac surgeons per million population than the average among high-income countries (7.15 per million), albeit more than the global average (1.64 per million) and far higher than the low-income country average (0.04 per million). In Canada, adult cardiac surgeons are active across 32 cardiac centres, representing 0.79 cardiac centres per million population, which is just above the global average (0.73 per million). In addition to centre and workforce variations, barriers to care exist in the form of waiting times, sociodemographic characteristics, insufficient virtual care infrastructure and electronic health record interoperability, and health care governance fragmentation. Meanwhile, Canada has highly favourable surgical outcomes, well established postacute cardiac care infrastructure, considerable spending on health, robust health administrative data, and effective health technology assessment agencies, which provides a foundation for continued improvements in care. In this narrative review, we describe successes and challenges surrounding access to cardiac surgery in Canada and globally.

Emergency Department Frequentation and Unscheduled Visits of Liver Transplant Patients: Ten Years Experience in Tertiary Care Center, Saudi Arabia.

Introduction and objectives Liver transplantation and its indications represent an increased burden on patients' health. This can be represented in a variety of ways, such as in emergency visits, unscheduled clinic visits, and unanticipated admissions. This study aims to analyze emergency department (ED) visits, the most common presenting complaints, and the outcomes of those visits. Methods A retrospective observational study was performed in which electronic medical records were reviewed for all patients who underwent liver transplantation and presented to the emergency department between October 2011 and October 2021. The following data were collected: demographics, comorbidities, liver transplant features, and emergency department visit data and outcomes. Recurrent visits were assessed and labeled as first, second, third, fourth, and fifth or more. Results A total of 699 patients and 5,225 visits were included in the analysis. Living donors accounted for 80% of all transplants. The mean post-operative length of stay was 22.6 ± 17.8. The majority of patients (74%) had at least one comorbidity, with diabetes (47%), hypertension (31%), and chronic kidney disease (CKD) (16%) being the commonest comorbidities; however, comorbidities were not associated with an increased risk of emergency department visits. Out of the 5,225 visits to the emergency department, 2,265 (41%) were within the first year. Emergency department visits in the first seven days after discharge amounted to 22% of total first visits. By 30 days, six months, and one year, they increased to 46%, 83%, and 91%, respectively. Living donor recipients had an average of 7.3 ED visits as compared to deceased donor recipients, who had an average of 8.4 ED visits. The most common presenting complaints were gastrointestinal (GI) symptoms (18%), infectious disease symptoms (9%), and respiratory symptoms (8%). There were a total of 296 patients who were readmitted at least once since discharge after liver transplantation. Conclusion The majority of first-time presentations to ED occurred in the first year post-transplant, marking this time period as critical for liver transplant patients. Our study also highlighted the continual presentations of liver transplant patients to the ED a few years post-transplant. This requires close scrutiny of the main causes of such presentations as well as comparison with other transplant cases to identify whether they are specific to liver transplants or not.

Association Between Low Serum Creatinine and Mortality in Patients With Severe Chronic Obstructive Pulmonary Disease.

INTRODUCTION:  Muscle mass may be a better predictor of mortality than BMI in chronic obstructive pulmonary disease (COPD). Serum creatinine depends on muscle mass and renal function; low values may predict higher mortality. OBJECTIVE:  To determine whether there is an association between low serum creatinine and mortality in severe COPD. METHODS: This is a retrospective study of serum creatinine values at admission and within the last year before admission. Outcomes measured were mortality at 30 days and one year after admission in patients with acute type 2 respiratory failure secondary to COPD, who were admitted over a one-year period to a respiratory ward (N = 130). The statistics were calculated using the chi-squared test. RESULTS:  There appears to be a significant relationship between the one-year pre-admission creatinine values and mortality at one year (p = 0.0003). CONCLUSIONS:  The relationship with mortality appears to be stronger with pre-admission creatinine values rather than the admission values and appears to predict the patients at the highest risk of mortality one year after admission.

An in vitro study of comparative evaluation of efficacy of electrochemically activated water as a root canal irrigant in smear layer removal.

AIM: The aim was to compare and evaluate the efficacy of electrochemically activated water (ECA) against maleic acid, Mixture of tetracycline, acid and detergent. ie; 3% doxycycline, 4.25% citric acid, and 0.5% Tween 80 detergent (MTAD), Sodium hypochlorite (NaOCl), and saline as root canal irrigants in removing the smear layer. MATERIALS AND METHODS: Twenty single canal mandibular premolars were randomly divided into five groups (n = 4), decoronated, prepared to working length, and instrumented till F3 using protaper gold rotary files. Each group was assigned a different irrigant. Saline-negative control and NaOCl-positive control. Teeth were sectioned and subjected to Scanning Electron Microscopic analysis. ECA was prepared using a custom-made apparatus having two chambers of capacity 50 ml each separated by a polymer membrane. About 40 ml of tap water was collected in each chamber. Two graphite electrodes were connected to the top of the compartments, linked to a power supply which initiates electrolysis, and the solutions obtained in anodic and cathodic compartments were collected. Statistical analysis was done using one-way ANOVA and Post hoc Tukey analysis. RESULTS: NaOCl, maleic acid, and ECA had similar smear layer removal efficacy. MTAD was less efficient than the other irrigants tested. Saline did not remove the smear layer. CONCLUSION: Electrochemically activated water has promising smear layer removal efficacy and is comparable with conventional root canal irrigants.

The impact of perioperative inotropes on the incidence of pancreatic leak following pancreaticoduodenectomy.

BACKGROUNDS/AIMS: Pancreatic leak and fistula formation following pancreatic resection is a dreaded complication associated with significant morbidity and mortality. The perioperative use of inotropes has been implicated in anastomotic dehiscence in other types of gastrointestinal surgery but their impact in pancreatic surgery remains unclear and a potentially modifiable risk factor for pancreatic leak. This study aims to assess the impact of perioperative inotrope infusion on the incidence of pancreatic leak following pancreaticoduodenectomy. METHODS: Retrospective data analysis of all patients undergoing pancreaticoduodenectomy at a tertiary HPB institute. Multivariate analysis and regression models assessed the impact of inotrope use against other known risk factors such as pancreatic duct size and gland texture. Pancreatic fistulae were graded as per ISGPF as Grade A (biochemical leak), Grade B and Grade C fistula. RESULTS: One-hundred and twenty-three (123) patients were included. A total of 52 patients (42%) developed a leak (29 grade A, 15 grade B, and 8 Grade C). In the fistula group, 28 patients (55%) received perioperative inotropes compared to 26 (35%) in the no fistula group. On univariate analysis, patients receiving inotropes (p=0.04) and patients with a soft pancreatic texture (p=0.003) had a statistically higher incidence of developing a pancreatic fistula of any grade. On multivariate analysis, only inotrope use was associated with an increased risk of developing a pancreatic fistula of any grade (OR 2.46, p=0.026), independent of pancreatic texture and pancreatic duct size. CONCLUSIONS: Perioperative inotrope use is associated with an increase incidence of pancreatic leak following pancreaticoduodenectomy and should therefore be used judiciously.