The Relevant Operators for the Hubbard Hamiltonian with a magnetic field term

The Hubbard Hamiltonian and its variants/generalizations continue to dominate the theoretical modelling of important problems such as high temperature superconductivity. In this note we identify the set of relevant operators for the Hubbard Hamiltonian with a magnetic field term.Comment: 19 pages, RevTe

Covid-19 Outbreak and Stock Market Performance: Evidence From Major Countries

The objective of this study is to determine the impact of COVID-19 on the performance of major Stock Market indices. This study uses the data of COVID-19 related confirmed cases, fatalities, and the closing prices of the selected indexes during the period from January 1 to July 31 in 2020. The findings of the study suggest that only COVID-19 confirmed cases are influencing the performance of the S&P 500 index, while the COVID 19 death cases are influencing the performance of both Shanghai composite index and KSE all indexes. However, no relationship exists between the NSE 500 index and COVID 19 confirmed and death cases. Keywords: COVID-19 and Stock Market, Major Stock Market and Pandemic. DOI: 10.7176/EJBM/12-24-09 Publication date:August 31st 202

Pattern and outcomes of admissions to the Medical Acute Care Unit of a tertiary teaching hospital in South Africa

A research report submitted to the University of the Witwatersrand, in fulfilment for the requirements of the degree of Master of Medicine in the branch of Internal Medicine. Johannesburg 2018.Background A Medical Acute Care Unit (MACU) was established at Chris Hani Baragwanath Academic Hospital (CHBAH) to provide comprehensive medical specialist care to the patients presenting with acute medical emergencies. Improved standards of health care delivery systems at the MACU may result in shorter hospital stay, better outcomes and less mortality. Objectives The objective of the study was to describe the demographics, diagnoses, pattern of diseases and the outcomes, including mortality of patients admitted to the MACU at the Chris Hani Baragwanath Academic Hospital (CHBAH). Methods A record review of 200 patients admitted to the MACU at CHBAH was performed from March 2015 to August 2015. The records were analysed for patient demographics, diagnosis at admission and duration of stay in MACU. The outcome was defined as transfer to the medical ward, Intensive Care Unit (ICU) or discharged home. The main causes of mortality were also recorded. Results Of the 200 patients, 59% were females. The mean age of the patients was 46 ± 17.2 years and the mean duration of stay at the MACU was 1.45 ± 1.25 days. Noncommunicable diseases accounted for 76% of admissions. The most frequently diagnosed conditions included: diabetic ketoacidosis acidosis (DKA) and hyperosmolar non-ketotic (HONK) (17.5%), non-accidental self-poisoning (16%), hypertensive emergencies (9.5%), decompensated cardiac failure (8%) and ischemic v heart disease (7%). Infectious diseases comprised 14% of the diagnoses of which pneumonias were the most common (5%). Most patients (77.5%) were transferred to medical wards, 12% to ICU, while 10% demised at the MACU. The main causes of death included sepsis (25%), DKA/HONK (20%), non-accidental self-poisoning (10%) and cardiac failure (10%). Conclusion Non-communicable diseases particularly diabetic emergencies were the main causes of admission to the MACU at CHBAH. During the study period, high rates of case improvement, patient discharge, shorter hospital stay, and less mortality were observed. The main cause of mortality was sepsis related.LG201

3D echocardiography allows rapid and accurate surgical planning in complex aortic root abscess cases

Despite 3D echocardiography (3DE) acquiring significantly greater data than standard 2D echocardiography (2DE), it is underutilised in assessing cardiac anatomy and physiology. A key advantage is the ability of a single 3DE acquisition to be post-processed to generate volume-rendered 3D models and an unlimited number of multiplanar reconstruction (MPR) images. We describe the case of a highly anxious patient with life-threatening complex aortic valve endocarditis and aortic root abscess, refusing transesophageal echocardiography (TOE) under general anaesthesia with tachycardia, breathlessness and acute kidney injury precluding accurate or safe gated (computed tomography) CT, who was comprehensively assessed with a rapid 3D-TOE under sedation. This led to timely surgery and an excellent outcome for the patient

Failure Load Prediction for Dapped-End Beam

Dapped-end beams are members of precast concrete structures that widely used nowadays in construction industry, especially in buildings and bridges due to its good lateral stability. The design analysis of dapped-end connections is complex and the re-entrant corner is identified as the weakest point because stress concentration develops in that area, which also known as disturbed regions. The accuracy of different codes and approaches in predicting failure load is yet to be fully explored. Therefore, investigation of the relative performance of different methods in predicting failure load capacity is crucial to be done. Besides, the incident of collapsed of Concorde Bridge has risen up many researchers’ attention and interest to conduct deeper research on design and strengthening of dapped-end connections to determine the load capacity for future design work purposes. Thus, this research project intended to determine the failure load of the dapped-end beams by using twodimensional non-linear finite element analysis (FEA) software called Vector2 and also using PCI design approach. The results from the Vector2 and also from PCI design approach will be used to compare with the load capacity obtained experimentally by Wang et al (2005) in their experimental research project as validation to determine which code or method is providing better accuracy in determining the failure load capacity. The analysis result obtained from FEA software and PCI Design Handbook is 47.6kN and 36.7kN, which is quite near compared to the experimental value, 42.24kN. Parametric study conducted to determine the sensitivity of different dapped-end parameters on the failure load capacity. As a conclusion, it is proven that the FEA software can be used to predict the failure load capacity accurately and can be used for parametric study