An Accelerated Homotopy Perturbation Method for Solving Nonlinear Two-Dimensional Volterra-Fredholm Integrodifferential Equations

We propose and apply coupling of the variational iteration method (VIM) and homotopy perturbation method (HPM) to solve nonlinear mixed Volterra-Fredholm integrodifferential equations (VFIDE). In this approach, we use a new formula called variational homotopy perturbation method (VHPM) and variational accelerated homotopy perturbation method (VAHPM). This approach is based on the form of He’s polynomials and on a new form of He’s polynomials. We discuss the convergence of the technique. Some numerical examples are introduced to verify the efficiency of this technique

Neonatal Outcomes in Type 1 Diabetes Pregnant Women, A Single-Center Retrospective Study

Background: Pregnancy in women with type 1 diabetes mellitus (T1DM) is associated with an increased risk of congenital malformations, and obstetric complications including increased rates of cesarean section birth, prematurity, and neonatal adverse outcomes including large for gestational age (LAG), and hypoglycemia. Our aim of this study is to investigate and evaluate the prevalence and the different neonatal outcomes of T1DM pregnant women compared to nondiabetic healthy pregnant women in a single-center experience to improve the effectiveness of interventions for the treatment of pregnant women with T1DM. Methods: This is a retrospective cohort study of 113 pregnant women (43 pregnant patients with T1DM and 70 non-diabetic healthy pregnant women) who underwent regular follow-in the antenatal period and delivered at King Fahad Military Medical Complex (KMMC) - Dhahran between 2018 and 2023. Results: A total of 117 pregnant women (47 with Type-1 diabetes mellitus-T1DM and 70 healthy controls) were included in the study. The proportion of elective C-sections was significantly high in women with T1DM 21 (44.7%) and the proportion of neonatal hypoglycemia who need treatment was also significantly high in diabetic women 20 (42.6%). NICU/SCBU admission was significantly high in diabetic women 23 (48.9%). Conclusion: The high prevalence of neonatal adverse outcomes especially hypoglycemia and intensive care admission of T1DM pregnant women compared to non-diabetic pregnant women indicates that this model of antenatal diabetes care must be improved to enhance maternal and fetal outcomes, especially in such high-risk groups and challenging problems

Microstructure and mechanical properties of Al-1050 during incremental ECAP

Incremental ECAP is a new method of ECAP process were the severe shear deformation is incrementally applied on the sample resulting in grain refining and new texture developing. The fundamental objective of the present work is an observation of effect of different passes of I-ECAP on microstructure and mechanical properties of AA1050 billet. To that end, 8 pass of I-ECAP have been carried out using Bc route and microstructure evolution and mechanical properties of the I-ECAPed samples have been studied. The EBSD and TEM analyses indicates that I-ECAP is as capable as conventional ECAP to grain refinements and a UFG structure is resulted after I-ECAP cycles. Tensile testing and hardness measurements indicates that mechanical properties of the Al-1050 billets increases dramatically by increasing the I-ECAP passes

Bilateral pneumothorax as possible atypical presentation of coronavirus disease 2019 (COVID-19)

© 2020 The Authors Coronavirus disease 2019 (COVID-19) is most frequently associated with a mild presentation of fever, cough, and shortness of breath. Typical radiographic findings of COVID-19 are bilateral ground-glass opacities on computed tomography (CT) scans. However, there have been instances of pneumothorax, giant bulla, and pneumomediastinum, mainly in elderly COVID-19 patients and predominately occurring at least one week after symptom onset. Here, we report a case where a healthy, young Hispanic man presented with three days of fever, cough, and dyspnea. On admission to the emergency department, he was found to have bilateral pneumothoraces, pneumomediastinum, and pneumopericardium requiring bilateral chest tubes. The patient had no predisposing risk factors for pneumothorax, such as a history of trauma, smoking, past intubations, asthma, high pressure oxygen delivery, or a history of prior pneumothorax. The only positive diagnostic test was a SARS-CoV-2 test by real-time reverse transcriptase–polymerase chain reaction assay. This case highlights the potential atypical presentation of a COVID-19 infection and is the first reported case, to our knowledge, that features bilateral spontaneous pneumothoraces, pneumomediastinum, and pneumopericardium as a probable rare presentation of COVID-19

Epidemiology of Autoimmune Diseases among Attendants of General Hospitals in Aseer region

It has long been recognized that environmental influences play an important role in the risk of developing Autoimmune disease. Defining specific pathogenic environmental mediators that may trigger the development or progression of autoimmune disease remains a focus of increasing investigative effort. Factors promoting disease may not be identical to factors that influence the severity or progression of the disorder. The cause(s) of autoimmune disorders remain largely unknown. Considerable evidence supports a role for environmental agents in inducing autoimmune disorders. OBJECTIVES: The study aims to explore the risk factors of autoimmune diseases among attendants of general hospitals in Aseer Region. Methods: case control study design was carried out  included 70  patients with multiple types of auto immune diseases attending general hospitals and primary health care centers in Abha city. They were clinically diagnosed as having autoimmune diseases. and 140 clinically free subjects , age and sex matched were included as controls. RESULTS: The present study included 70 autoimmune disease patients predominantly females (88.4%). Their mean age was 42.7 ± 12.1 years and disease duration was 11.2 ± 7.2 years. The mean age of the control group was 47.1 ± 13.6 years with no significant differences in the demographic data between the patients and control (p > 0.05). This study found no significant differences between cases with autoimmune diseases and sociodemographic characteristics. Conclusion :There is multiple determinants and risk factors affecting the occurrence of autoimmune diseases. Familial history, psychological stresses, hormonal supplementation, using hair dyes, smoking and recent vaccination were significant factors associated with autoimmune diseases. Keywords: Epidemiology, autoimmune, diseases, Aseer regio

An interdisciplinary approach to the study of kiln firing: a case study from the Campus Galli open-air museum (southern Germany)

Pottery kilns are a common feature in the archaeological record of different periods. However, these pyrotechnological installations are still seldom the target of interdisciplinary investigations. To fill this gap in our knowledge, an updraft kiln firing experiment was run at the Campus Galli open-air museum (southern Germany) by a team consisting of experimental archaeologists, material scientists, geoarchaeologists, and palaeobotanists. The entire process from the preparation of the raw materials to the firing and opening of the kiln was carefully recorded with a particular focus on the study of the raw materials used for pottery making, as well as on fuel usage. The temperatures were monitored by thermocouples placed at different positions in the combustion and firing chambers. In addition, thermocouples were installed within the kiln wall to measure the temperature distribution inside the structure itself. Unfired raw materials as well as controlled and experimentally thermally altered ceramic samples were then characterised with an integrated analysis including ceramic petrography, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and portable X-ray fluorescence (pXRF). Our work provides data about mineralogical and microstructural developments in both pottery kiln structures and the ceramics produced in this type of installations. This is helpful to discuss the limits and potential of various scientific analyses commonly used in ancient ceramic pyrotechnological studies. Overall, our work contributes to a better understanding of updraft kiln technology and offers guidelines on how to address the study of this type of pyrotechnological installations using interdisciplinary research strategies

Assessment of Global Kidney Health Care Status.

Kidney disease is a substantial worldwide clinical and public health problem, but information about available care is limited.To collect information on the current state of readiness, capacity, and competence for the delivery of kidney care across countries and regions of the world.Questionnaire survey administered from May to September 2016 by the International Society of Nephrology (ISN) to 130 ISN-affiliated countries with sampling of key stakeholders (national nephrology society leadership, policy makers, and patient organization representatives) identified by the country and regional nephrology leadership through the ISN.Core areas of country capacity and response for kidney care.Responses were received from 125 of 130 countries (96%), including 289 of 337 individuals (85.8%, with a median of 2 respondents [interquartile range, 1-3]), representing an estimated 93% (6.8 billion) of the world's population of 7.3 billion. There was wide variation in country readiness, capacity, and response in terms of service delivery, financing, workforce, information systems, and leadership and governance. Overall, 119 (95%), 95 (76%), and 94 (75%) countries had facilities for hemodialysis, peritoneal dialysis, and kidney transplantation, respectively. In contrast, 33 (94%), 16 (45%), and 12 (34%) countries in Africa had facilities for hemodialysis, peritoneal dialysis, and kidney transplantation, respectively. For chronic kidney disease (CKD) monitoring in primary care, serum creatinine with estimated glomerular filtration rate and proteinuria measurements were reported as always available in only 21 (18%) and 9 (8%) countries, respectively. Hemodialysis, peritoneal dialysis, and transplantation services were funded publicly and free at the point of care delivery in 50 (42%), 48 (51%), and 46 (49%) countries, respectively. The number of nephrologists was variable and was low (<10 per million population) in Africa, the Middle East, South Asia, and Oceania and South East Asia (OSEA) regions. Health information system (renal registry) availability was limited, particularly for acute kidney injury (8 countries [7%]) and nondialysis CKD (9 countries [8%]). International acute kidney injury and CKD guidelines were reportedly accessible in 52 (45%) and 62 (52%) countries, respectively. There was relatively low capacity for clinical studies in developing nations.This survey demonstrated significant interregional and intraregional variability in the current capacity for kidney care across the world, including important gaps in services and workforce. Assuming the responses accurately reflect the status of kidney care in the respondent countries, the findings may be useful to inform efforts to improve the quality of kidney care worldwide

The origin of fracture in the I-ECAP of AZ31B magnesium alloy

Magnesium alloys are very promising materials for weight-saving structural applications due to their low density, comparing to other metals and alloys currently used. However, they usually suffer from a limited formability at room temperature and low strength. In order to overcome those issues, processes of severe plastic deformation (SPD) can be utilized to improve mechanical properties, but processing parameters need to be selected with care to avoid fracture, very often observed for those alloys during forming. In the current work, the AZ31B magnesium alloy was subjected to SPD by incremental equal-channel angular pressing (I-ECAP) at temperatures varying from 398 K to 525 K (125 °C to 250 °C) to determine the window of allowable processing parameters. The effects of initial grain size and billet rotation scheme on the occurrence of fracture during I-ECAP were investigated. The initial grain size ranged from 1.5 to 40 µm and the I-ECAP routes tested were A, BC, and C. Microstructures of the processed billets were characterized before and after I-ECAP. It was found that a fine-grained and homogenous microstructure was required to avoid fracture at low temperatures. Strain localization arising from a stress relaxation within recrystallized regions, namely twins and fine-grained zones, was shown to be responsible for the generation of microcracks. Based on the I-ECAP experiments and available literature data for ECAP, a power law between the initial grain size and processing conditions, described by a Zener–Hollomon parameter, has been proposed. Finally, processing by various routes at 473 K (200 °C) revealed that route A was less prone to fracture than routes BC and C