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The broad demonstration of grid-forming converters (GFMs) in microgrid applications has been well documented. Following this, the idea of GFM was assessed for its potential use in large-scale linked networks that include transmission and distribution systems combined with renewable energy sources. As a result, a thorough examination of GFM performance became imperative. This study provides a comprehensive examination of GFMs, encompassing fundamental principles, control mechanisms, implementation strategies, operational aspects, and potential avenues for further research. The capacity of GFMs to withstand system disturbances is of utmost importance for ensuring the overall stability of the system, particularly in situations where inertial response is diminished. Classical control methods are inadequate in addressing transient stability circumstances, necessitating the development of current control approaches to overcome these limitations. The utilization of GFM control is becoming increasingly important in the global initiative to establish a sustainable energy system through the integration of renewable energy. GFM control is particularly significant as it determines the level of controllability over non-dispatchable and variable generation, especially on a larger scale, thus contributing to the practical realization of this initiative. Therefore, an extensive and evaluative examination of many control systems, control theories, and algorithms has been conducted in the last twenty years. This study provides a comprehensive classification of control objectives and applications, emphasizing their importance and effectiveness. The findings of this study are equally applicable to various interdisciplinary fields such as power system operation, power electronics, renewable energy integration, advanced control, and smart grids. [ABSTRACT FROM AUTHOR]

Study Design: Cross sectional. Background: Functional gastrointestinal disorders (FGIDs) are a class of disorders that are identified and categorized based on symptoms because they lack a significant deviation from the normal histological, anatomical, and biochemical characteristics. A chronic gastrointestinal illness called irritable bowel syndrome (IBS) is characterized by recurring stomach pain or discomfort linked to a changed bowel routine. Global research has determined that between 5 and 20% of people worldwide suffer from IBS. Gastroenterology clinics have received referrals for 30% to 50% of IBS patients. A thorough review of the patient's symptoms, a thorough history (including information about diet, medications, medical, surgical, and psychological history), an assessment of the patient for the presence of warning signs (such as "red flags" of anemia, hematochezia, unintentional weight loss, or a family history of colorectal cancer or inflammatory bowel disease), and a guided physical examination are all necessary to make the traditional diagnosis of IBS. Methods: In Southern Saudi Arabia, IBS was targeted on all accessible groups using a descriptive cross-sectional strategy. Participants in the poll had to be Saudi citizens who were 18 years of age or older, had IBS, and resided in the Aseer region. Data collection was started after receiving approval from the institutional ethics committee. An electronic questionnaire that was already pre-structured was used to collect data from the participants. Between April and June 2021. Results: Out of total 1622 respondents 55.49% were females while 44.51% were males 61.6% have 5-10 working hours ,23.3% were working in civil areas, 25.9% were from southern region, 83.2% were living in cities, 61.6% have income level 5000 to 15000SAR, 67.82% were nonsmokers 21.95 & 28.1% were suffering from DM and HTN respectively. We did not observe gender wise significance difference in the prevalence of IBS. Conclusion: This is the first study to quantify the prevalence of IBS and FD, as well as the risk factors related with these disorders, in the Saudi city of Abha. Our findings are useful in bridging the epidemiological data gap Aseer region IBS, FD, and OS. Future research would allow for a better knowledge of the complicated biology of both disorders, as well as better management tailored to the risk factors associated. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to determine the prevalence of low back pain (LBP) and to identify risk factors associated with LBP among medical students. Materials and Methods: A cross-sectional study was conducted among 2021 medical students from four medical colleges in Saudi Arabia during the academic year 2019–2020. A self-administered questionnaire was conducted and included three sections: demographic data, risk factors of LBP, and prevalence of LBP (during lifetime, past 12 months, and past 7 days). Data were analyzed using SPSS. Results: A total of 2021 medical students responded to our survey. The participants were 57.1% female and 42.9% male. Most of the students’ ages (76.3%) ranged from 20 to 24 years. Medical students younger than 20 and older than 24 were 21.8% and 1.9%, respectively. The prevalence of LBP was 80.7% at any time, 67.6% in the past 12 months, and 38.2% in the past 7 days. Females were found to have higher prevalence of LBP than males(P < 0.0001), 95% confidence interval (CI) (1.37, 2.04). History of physical trauma to the back was significantly associated with LBP (P < 0.0001), 95% CI (1.32, 2.40). A lack of daily exercise was also found to be associated with LBP (P = 0.015), 95% CI (1.05, 1.55). LBP affected the daily functions, such as walking and sleeping, of 30.1% of medical students. Around 11% of medical students sought medical care because of LBP. Conclusions: We conclude that the prevalence of LBP is high among Saudi medical students. LBP seemed to be higher in females and associated with history of back trauma. Back care awareness should be emphasized among medical students. [ABSTRACT FROM AUTHOR]

Background: Anterior Cruciate Ligament (ACL) reconstruction is a well-known surgical knee procedure performed by orthopaedic surgeons. There is a general consensus for the effectiveness of a postoperative ACL reconstruction rehabilitation program, however there is little consensus regarding the optimal components of a program Objective of the Study: to assess the merits and demerits of current ACL reconstruction rehabilitation programs and interventions based on the evidence supported by previously conducted systematic reviews. Methods: a Systematic search in the scientific database (Medline, Scopus, EMBASE , and Google Scholer) between 1970 and 2017 was conducted for all relevant Systematic reviews discussing the primary endpoint ( ACL reconstruction rehabilitation ) studies were analyzed and included based on the preset inclusion and exclusion criteria. Study screening and quality was assessed against PRISMA guidelines and a best evidence synthesis was performed. Results: the search results yielded five studies which evaluated eight rehabilitation components (bracing, Continuous passive motion (CPM), neuromuscular electrical stimulation (NMES), open kinetic chain (OKC) versus closed kinetic chain (CKC) exercise, progressive eccentric exercise, home versus supervised rehabilitation, accelerated rehabilitation and water based rehabilitation). A strong evidence suggested no added benefit of short term bracing (0-6 weeks post-surgery) compared to standard treatment. Whilst a moderate evidence reinforced no added advantage of continuous passive motion to standard treatment for boosting motion range. Furthermore, a moderate evidence of equal effectiveness of closed versus open kinetic chain exercise and home versus clinic based rehabilitation, on a range of short term outcomes. There was inconsistent or limited evidence for some interventions including: the use of NMES and exercise, accelerated and non-accelerated rehabilitation, early and delayed rehabilitation, and eccentric resistance programs after ACL reconstruction. Conclusion: short term post-operative bracing and continuous passive motion (CPM) introduce no benefit over standard treatment and thus not recommended. A moderate evidence suggested equal efficiency for 1) CKC and OKC are equally effective for knee laxity, pain and function, at least in the short term (6-14 weeks) after ACL reconstruction and 2) home based and clinic based rehabilitation. Nevertheless, the degree of physiotherapy input remains unclear. [ABSTRACT FROM AUTHOR]