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Diurnal and seasonal temperature variations cause uniform temperature changes, vertical temperature gradients, and horizontal temperature gradients. Vertical temperature gradients occur when the bridge deck absorbs heat due to solar radiation more than the bottom parts of bridge girders. Consequently, the vertical temperature gradient causes redistribution of bearing reactions, and induces additional flexural stresses in continuous spans. Estimating the vertical temperature gradient effect on continuous concrete bridges requires knowledge of thermal analysis of statically indeterminate structures or advanced three-dimensional (3 D) finite element (FE) analysis. Therefore, this article focuses on developing a simplified analysis method for estimating vertical temperature variations effects on continuous prestressed concrete bridge girders, which is required for bridge design. Restraint moments induced by vertical temperature gradients are investigated using 3 D FE analysis. A total of 115 bridges with different configurations (number of spans, girder spacing, and girder type) were analyzed to estimate the positive thermal moments at support locations. Results from these analyses were then used to develop simplified equations for estimating the positive restraint moments due to vertical temperature gradients from AASHTO LRFD Bridge Design Specifications (BDS). The developed equations are validated using John James Audubon Bridge #2 field data, and for other AASHTO LRFD temperature zones. [ABSTRACT FROM AUTHOR]

Background: SARS-CoV-2 was identified as a worldwide fatal pandemic that causes acute respiratory infections. The aim of this work was to compare the effect of Using combined therapy: (tocilizumab with Methylprednisolone) versus using (Methylprednisolone alone) as immuno-modulatory therapy on 28 days mortality mortality, need for mechanical ventilation & adverse effects. Methods: This retrospective observational cohort study was carried out on 60 patients diagnosed as having covid 19 infection with cytokine storm and severe acute respiratory syndrome during the period(2020-2021). Patients were divided into 2 groups: (TCZ+MP)group received 2 doses of tocilizumab within 24hrs (5mg/kg in each dose) in addition to a dose of methylprednisolone (2mg/kg/day) for 7 days and(MP)group: received only a dose of methylprednisolone (2mg\kg\day) for 7 days. All patients were subjected to routine laboratory investigations (Complete blood count, liver function tests, kidney function tests, LDH, ferritin, D-dimer, frequent ABGs (P/F ratio), CRP, IL6, procalcitonin & albumin), and radiology investigation (Chest x-ray and CT chest). Results: 60 patients with ARDS(both genders) were included in this study, in TCZ+MPgroup, 8(26.67%) of 30 patients died, compared to 17(56,67%) of 30patients in (MP)group, so mortality rate was significantly lower in patients on TCZ+MPgroup than those on (MP)group (P value =0.018). In TCZ+MPgroup, 12(40%) of 30 patients needed mechanical ventilation compared to 22(73.33%) of 30 patients in MP group, so Number of patients who required mechanical ventilation was significantly lower in patients on TCZ+MPgroup than MP group (P value = 0.009). Adverse effects of intervention drugs after 28 days were insignificantly different between both groups (P value = 0.018). Conclusions: In patients with severe COVID-19 infection, combination therapy of tocilizumab &methylprednisolone reduced mortality rate and need for mechanical ventilation as compared with the use of methylprednisolone alone. [ABSTRACT FROM AUTHOR]

Background Umbilical herniorrhaphy in cirrhotic patients with ascites is not usually done due to high postoperative morbidity and mortality rates. However, recent reports recommending elective surgery in these patients with perioperative preparation will result in good and safe outcome to avoid emergent repair later on. The aim of this study was to evaluate the outcome of umbilical herniorrhaphy in patients with liver cirrhosis and ascites regarding postoperative morbidity and mortality. Patients and methods A retrospective study was done on 102 patients with umbilical hernia and ascites in the period between March 2014 and April 2017 who had undergone surgical repair either electively or emergently at Tanta University Hospital. Patient characteristics, morbidity, and mortality are recorded. Results Seventy-two men and 30 women with a mean age of 51.3 years were analyzed. Eighteen (17.6%) patients were of Child–Pugh–Turcotte (CPT) class A, 54 (53%) patients were of class B, and 30 (29.4%) patients were of class C. The patients had a model for end-stage liver disease score of 16.23. Fifty-seven patients underwent elective operations while 45 patients underwent emergency surgery of whom 24 patients had incarceration, 12 cases had rupture of the hernia sac, and nine cases had skin ulceration or necrosis. Primary repair was done in 60 (58.8%) patients and meshes were used in 42 (41.2%) patients. The morbidity and mortality rates were 37.2% (n=38) and 3.9% (n=4), respectively. Conclusion Elective repair of umbilical hernia can be performed easily and safely in cirrhotic patients with ascites with good perioperative preparation with better results than emergent repair. [ABSTRACT FROM AUTHOR]