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Abstract In the islanded microgrid, it is necessary to distribute the harmonic powers correctly among generators and mitigate the voltage harmonics at the point of common coupling (PCC) for effective microgrid operation. These control objectives are hard to satisfy at the same time with only one virtual impedance component. To simultaneously improve the microgrid voltage quality and share the distortion powers, a consensus‐based distributed power‐sharing scheme is proposed along with PCC harmonics mitigation. In the proposed control scheme, the controllable parts of output impedance at the fundamental and harmonic frequencies are separately tuned by simple integral controllers without depending on feeder impedance parameters. Compared to conventional control schemes, the proposed method is less complicated while ensuring a high voltage quality despite sudden changes in load power. A small‐signal state‐space model of the microgrid is analysed to validate the stability of the proposed control scheme, and its effectiveness is verified by experiments with a scaled‐down microgrid system.

Abstract Research on pancreatic cancer has transformed with the advent of organoid technology, providing a better platform that closely mimics cancer biology in vivo. This review highlights the critical advancements facilitated by pancreatic organoid models in understanding disease progression, evaluating therapeutic responses, and identifying biomarkers. These three-dimensional cultures enable the proper recapitulation of the cellular architecture and genetic makeup of the original tumors, providing insights into the complex molecular and cellular dynamics at various stages of pancreatic ductal adenocarcinoma (PDAC). We explore the applications of pancreatic organoids in dissecting the tumor microenvironment (TME); elucidating cancer progression, metastasis, and drug resistance mechanisms; and personalizing therapeutic strategies. By overcoming the limitations of traditional 2D cultures and animal models, the use of pancreatic organoids has significantly accelerated translational research, which is promising for improving diagnostic and therapeutic approaches in clinical settings, ultimately aiming to improve the outcomes of patients with pancreatic cancer.

Background. Emergency groin hernia is an understudied research field despite its severity requiring emergency surgery associated with high postoperative morbidity and mortality rates. Therefore, the purpose of this study was to investigate the efficacy, critical technical elements, and management of problems associated with the transabdominal preperitoneal (TAPP) laparoscopic technique for adult patients in need of an emergency groin hernia repair. Methods. We analyzed adult patients who were treated between January 2021 and March 2023 for emergency groin hernia repair. These patients' preoperative data were examined. Results. The surgery was successfully performed on all 21 patients. The duration of the surgery was 71.6±19.7 minutes (range, 45–120 minutes). The hospitalization time was 3.2±2.2 days (range, 2–5 days). Conclusions. The TAPP approach is a secure and efficient method for performing emergency groin hernia repair in adults due to its ability to evaluate hernia content and reduce the incidence of incisional infection.

Objectives: Quality of surgery has recently become an essential topic in the prognosis of colon cancer. Complete mesocolic excision for colon cancer has recently gained popularity with high-quality surgery. Patient specimens after complete mesocolic excision with central vessel ligation procedures have an integrity of the mesocolon and the yield of three fields of lymph node harvest. We apply the glacial acid, absolute ethanol, water, and formaldehyde solution to each specimen based on the Japanese classification of lymph node groups and station numbers. We aim to identify the distribution and status of lymph node metastasis according to each tumor site and some pathological characteristics related to this disease. Methods: A prospective cohort study was performed on 45 laparoscopic complete mesocolic excision surgery patients. Results: 2791 lymph nodes were harvested after complete mesocolic excision surgery. The average number was 62.0 ± 22.3 nodes. The mean tumor size (in the largest dimension) was 4.2 ± 1.8 cm. The average length of the resected bowel segments was 29.1 ± 7.7 cm. There are 63 (2.3%) node metastases in 2791 lymph nodes, in which 17/45 (37.8%) patients had pN(+). The minimum positive node size was 1 mm. The positive pericolic lymph nodes (station 1) accounted for the highest rate, with 53 nodes (1.9%). The number of lymph nodes in young age ⩽60 is more significant than in older. The results were similar, with a more significant node retrieval in the group with a tumor size >4.5 cm and specimen length >25 cm. The number of lymph nodes in lower tumor invasive (pT1,3) was smaller than pT4. Our research shows that the cecum, ascending, and descending colon had greater nodes than others, with a mean number of 78.6, 74.2, and 71.3, respectively. Conclusions: The metastasis and harvested lymph nodes accounted for the highest rate of colon cancer in station 1 and the lowest rate in station 3. The number of retrieved lymph nodes was significantly associated with tumor location, size, specimen length, and patient age.

Past research examining lay theories of the origins of prejudice has focused on white Americans and has not considered how Black Americans’ lay theories of prejudice may impact emotion regulation following discrimination. Across three samples of Black Americans (N = 419), the present research examined relationships between endorsement of two lay theories of prejudice origins (1, beliefs that prejudice stems from shared social ignorance and 2, that prejudice stems from malice). Stronger beliefs that prejudice stems from shared ignorance were associated with greater expression suppression following experiences of racial discrimination (studies 1b and 2), which was, in turn, associated with psychological distress (study 2). By centering the beliefs and experiences of Black Americans in response to discrimination events, the present research has implications for understanding how emotion regulation following racial discrimination is impacted by marginalized groups’ conceptualizations of prejudice. Future research should investigate how these factors impact health disparities.

The paper delves into an in-depth analysis of the intrinsic resistance of the inverted pendulum system which causes the modeling of the system to differ from the actual system. Our primary objective revolves around the implementation and subsequent optimization of fuzzy logic controllers (FLC), drawing inspiration from human perceptual assessments. The processing comprises comprehensive mathematical system modeling, intrinsic resistance examination, and improved fuzzy logic control with detailed membership function and rule design. In addition, we conduct a comparative analysis with the widely recognized linear quadratic regulator (LQR) algorithm, which is considered the conventional control algorithm. The result demonstrates that the improved FLC outperforms the conventional LQR algorithm overshoot mitigation, thereby underscoring its superior efficacy and optimality. [ABSTRACT FROM AUTHOR]

The cutting temperature in hard turning is extremely high, which reduces tool life, lowers machined-surface quality, and affects dimensional control. However, hard turning differs greatly from conventional turning in that the cutting process mainly happens at the tool-nose radius due to the extremely shallow depth of the cut. This paper provides a comprehensive and systematic analysis of this issue based on an evaluation of tool geometry in hard turning via finite element analysis (FEA) simulations and experiments. The effect of tool angles on cutting temperature in hard turning is analyzed. The impacts of cutting-edge angle, rake angle, inclination angle, and average local rake angle on the cutting temperature are investigated via central composite design (CCD). The simulated results and the empirically measured cutting temperature exhibit comparable patterns, with a minor 2% difference. Increasing the cutting-edge angle, negative rake angle and negative inclination angle enhances the local negative rake angles of the cutting-edge elements at the tool-nose radius involved in the cutting process. Notably, the most important component influencing cutting temperature in hard turning is the inclination angle, as opposed to normal turning, where the rake angle dominates the heat generation. Following this is the cutting-edge angle and the rake angle, which each contribute 40.75%, 32.39%, and 7.03%. These findings could enhance the application of the hard-turning technique by improving tool life and surface quality by focusing on optimizing the inclination angle. [ABSTRACT FROM AUTHOR]

In recent years, high-power three-level neutral point clamped (NPC) inverters have significantly increased, particularly in the renewable energy sector and industries. These inverters are crucial in applications such as offshore wind farms and high-power motor drives, where reducing switching losses and improving the overall longevity, efficiency, and reliability of inverter systems are key. While conventional space vector pulse width modulation (SVPWM) has been used to reduce switching losses, it also increases the computational burden in the αβ coordinates. Our study introduces an effective and highly efficient carrier-based discontinuous pulse width modulation (DPWM) method specifically designed for high power factor loads to address this challenge. This approach significantly reduces computational execution time by adding the zero-sequence function into the fundamental signals. The efficiency of our new method is evident in the results: the proposed DPWM has successfully reduced switching losses, leading to a substantial enhancement of system efficiency. Our space vector analysis and simulation results, achieved using MATLAB and PLECS software, further validate the efficiency of our approach. Additionally, experimental results with a smallscale three-phase NPC inverter were conducted to validate the effectiveness and efficiency of the proposed DPWM. [ABSTRACT FROM AUTHOR]

Abstract Medical staff caring for COVID-19 patients face mental stress, physical exhaustion, separation from families, stigma, and the pain of losing patients and colleagues. Many of them have acquired SARS-CoV-2 and some have died. In Africa, where the pandemic is escalating, there are major gaps in response capacity, especially in human resources and protective equipment. We examine these challenges and propose interventions to protect healthcare workers on the continent, drawing on articles identified on Medline (Pubmed) in a search on 24 March 2020. Global jostling means that supplies of personal protective equipment are limited in Africa. Even low-cost interventions such as facemasks for patients with a cough and water supplies for handwashing may be challenging, as is ‘physical distancing’ in overcrowded primary health care clinics. Without adequate protection, COVID-19 mortality may be high among healthcare workers and their family in Africa given limited critical care beds and difficulties in transporting ill healthcare workers from rural to urban care centres. Much can be done to protect healthcare workers, however. The continent has learnt invaluable lessons from Ebola and HIV control. HIV counselors and community healthcare workers are key resources, and could promote social distancing and related interventions, dispel myths, support healthcare workers, perform symptom screening and trace contacts. Staff motivation and retention may be enhanced through carefully managed risk ‘allowances’ or compensation. International support with personnel and protective equipment, especially from China, could turn the pandemic’s trajectory in Africa around. Telemedicine holds promise as it rationalises human resources and reduces patient contact and thus infection risks. Importantly, healthcare workers, using their authoritative voice, can promote effective COVID-19 policies and prioritization of their safety. Prioritizing healthcare workers for SARS-CoV-2 testing, hospital beds and targeted research, as well as ensuring that public figures and the population acknowledge the commitment of healthcare workers may help to maintain morale. Clearly there are multiple ways that international support and national commitment could help safeguard healthcare workers in Africa, essential for limiting the pandemic’s potentially devastating heath, socio-economic and security impacts on the continent.

This article discussed Vietnam’s ongoing efforts to decentralize the health system and its fitness to respond to global health crises as presented through the Covid-19 pandemic. We used a general review and expert’s perspective to explore the topic. We found that the healthcare system in Vietnam continued to decentralize from a pyramid to a wheel model. This system shifts away from a stratified technical hierarchy of higher- and lower-level health units (pyramid model) to a system in which quality healthcare is equally expected among all health units (wheel model). This decentralization has delivered more quality healthcare facilities, greater freedom for patients to choose services at any level, a more competitive environment among hospitals to improve quality, and reductions in excess capacity burden at higher levels. It has also enabled the transformation from a patient-based traditional healthcare model into a patient-centered care system. However, this decentralization takes time and requires long-term political, financial commitment, and a working partnership among key stakeholders. This perspective provides Vietnam’s experience of the decentralization of the healthcare system that may be considered as a useful example for other countries to strategically think of and to shape their future system within their own socio-political context.

Introduction Despite early adoption of the WHO guidelines to deliver lifelong antiretroviral (ARV) regimen to pregnant women on HIV diagnosis, the HIV prevention of mother to child transmission programme in Papua New Guinea remains suboptimal. An unacceptable number of babies are infected with HIV and mothers not retained in treatment. This study aimed to describe the characteristics of this programme and to investigate the factors associated with programme performance outcomes.Methods We conducted a retrospective analysis of clinical records of HIV-positive pregnant women at two hospitals providing prevention of mother to child transmission services. All women enrolled in the prevention of mother to child transmission programme during the study period (June 2012–June 2015) were eligible for inclusion. Using logistic regression, we examined the factors associated with maternal loss to follow-up (LTFU) before birth and before infant registration in a paediatric ARV programme.Results 763 of women had records eligible for inclusion. Demographic and clinical differences existed between women at the two sites. Almost half (45.1%) of the women knew their HIV-positive status prior to the current pregnancy. Multivariate analysis showed that women more likely to be LTFU by the time of birth were younger (adjusted OR (AOR)=2.92, 95% CI 1.16 to 7.63), were newly diagnosed with HIV in the current/most recent pregnancy (AOR=3.50, 95% CI 1.62 to 7.59) and were in an HIV serodiscordant relationship (AOR=2.94, 95% CI 1.11 to 7.84). Factors associated with maternal LTFU before infant registration included being primipara at the time of enrolment (AOR=3.13, 95% CI 1.44 to 6.80) and being newly diagnosed in that current/most recent pregnancy (AOR=2.49, 95% CI 1.31 to 4.73). 6.6% (50 of 763) of exposed infants had a positive HIV DNA test.Conclusions Our study highlighted predictors of LTFU among women. Understanding these correlates at different stages of the programme offers important insights for targets and timing of greater support for retention in care.

Introduction Hepatitis C virus (HCV) is a global public health threat, and novel models of care are required to treat those currently or previously at highest risk of infection, particularly persons who inject drugs (PWID; ever injected), as conventional healthcare models do not have the reach to deliver cure of HCV to disadvantaged, disproportionately affected communities. In Western Europe and Australasia, it is estimated that HCV affects between 0.4% and 1.0% of the regions’ populations, accordingly, it affects between 0.4% and 0.7% of the populations of countries in this study (Scotland, Wales and Australia). Reaching mEthadone users Attending Community pHarmacies with HCV (REACH HCV) will evaluate community pharmacy-based diagnostic outreach and HCV treatment against conventional HCV testing and treatment pathways for clients receiving opioid substitution therapy (OST) in community pharmacies.Methods and analysis REACH HCV is an international multicentre cluster randomised controlled trial with sites in Scotland, Wales and Australia. The sites are community pharmacies which are randomised equally to one of two pathways: the pharmacy intervention pathway or the education-only (control) pathway. Participants are recruited from OST clients in these pharmacies.In the pharmacy intervention pathway, participants receive a rapid point-of-care HCV PCR test in their pharmacy by a study outreach nurse. If positive, direct-acting antivirals (DAAs) are delivered to participants via their pharmacist in line with their OST schedule.In the education-only pathway, pharmacists counsel OST clients on HCV and refer them to the nearest nurse-led clinic or general practitioner offering HCV testing according to standard care protocols. If positive, DAAs are delivered as in the intervention pathway.The primary endpoint for both pathways is sustained viral response at 12 weeks post-treatment . Secondary outcomes are: cost-efficacy by pathway; participants tested by pathway; adherence to therapy by pathway and impact of blood test results on treatment decisions.A statistical analysis plan will be finalised prior to data lock. Analysis will be by intention to treat (ITT) to show superiority. Modified ITT analysis will also be undertaken to explore the steps in the pathways.Ethics and dissemination The trial received ethical favourable opinion from the East of Scotland Research Ethics Committee 2 (19/ES/0025) for UK sites and approval from the Alfred Hospital Ethics Committee (148/19) for Australian sites and complies with principles of Good Clinical Practice. Final results will be presented in peer-reviewed journals and at relevant conferences.Trial registration number ClinicalTrials.gov Registry NCT03935906.Protocol version V.4.0—19 March 2020.

Past research examining lay theories of the origins of prejudice has focused on white Americans and has not considered how Black Americans' lay theories of prejudice may impact emotion regulation following discrimination. Across three samples of Black Americans (N = 419), the present research examined relationships between endorsement of two lay theories of prejudice origins (1, beliefs that prejudice stems from shared social ignorance and 2, that prejudice stems from malice). Stronger beliefs that prejudice stems from shared ignorance were associated with greater expression suppression following experiences of racial discrimination (studies 1b and 2), which was, in turn, associated with psychological distress (study 2). By centering the beliefs and experiences of Black Americans in response to discrimination events, the present research has implications for understanding how emotion regulation following racial discrimination is impacted by marginalized groups' conceptualizations of prejudice. Future research should investigate how these factors impact health disparities. [ABSTRACT FROM AUTHOR]