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Current study deals with strength and seismic ductility assessment of reinforced high strength concrete (HSC) columns. We have studied the nonlinear response of HSC columns with various reinforcement and axial force ratios subjected to cyclic loading. Study consists of primary verification of mathematical nonlinear model and further calibration to ensure accuracy. An existing experimental work is assumed as verification pilot that consists of four columns. Column members differ in the strength and axial force. Concrete has 63.1 MPa mean strength and 0.3% crushing strain. The longitudinal and transverse reinforcements are according to ACI 318 regulations in experiment. We used the nonlinear fiber-element code in OpenSees environment for modeling and analysis of models. The existing proposed stress-strain curve is modified to ensure validity of assessment. Calibration procedure led to conclusion that the post-yield slope needs to be modified in HSC model as the average value of ACI 363 reference. We have developed twelve extra models to estimate the interaction of concrete strength, rebar ratio and the axial force effect on the seismic performance. Parametric study of calibrated models reveals that the seismic energy dissipation in HSC members is function of the provided longitudinal reinforcement ratio and lateral confining stirrup amount. [ABSTRACT FROM AUTHOR]

Gastrocolic reflux is a troublesome symptom causing repeated aspiration or chocking in patients underwent retrosternal colon interposition. Various techniques were described to avoid such complication, however, they entail complicated technique that may jeopardize the viability of the graft or cause obstructing symptoms. A simple antireflux procedure is described here alleviating this problem. Over the last 7 years, 87 patients had gastrocolic antireflux procedure for cologastric anastomosis; 75 patients as a primary procedure (group 1) and 12 patients as a secondary procedure treating symptomatic reflux (group 2). The technique entails the creation of cologastric angle after finishing the cologastric anastomosis by applying three stitches between the colon and the stomach, thus tucking the colon to the stomach for 3-4 cm. Gastrocolic reflux was evaluated clinically and radiologically 3 months postoperatively. In group 1, three cases (4%) suffered symptomatic gastrocolic reflux, and seven cases (9.3%) had radiological asymptomatic mild reflux, while all patients in group 2 had complete alleviation of their symptoms with gastrogram showing no reflux. Gastrocolic reflux can be treated simply by creation of cologastric angle; however, controlled trial is needed to confirm its effectiveness in comparison to other described techniques. [ABSTRACT FROM AUTHOR]

This study introduces a suite of robust models aimed to advance the determination of physiochemical properties in heavy oil refinery fractions. By integrating real-time analytical technique inside the refinery analysis, we have developed a single analyzer capable of employing six partial least square regression equations. These designed models enable to provide real-time prediction of critical petroleum properties, such as sulfur content, micro carbon residues (MCR), asphaltene content, heating value, and the concentrations of nickel and vanadium metals. Specifically tailored for heavy oil in refinery feeds with an American petroleum institute (API) gravity range of 3° to 32° and sulfur content of 2.8 to 5.5 wt%, the models streamline the analysis process within refinery operations, bridging the gap between catalytic and non-catalytic processes across refinery units. The accuracy of our physiochemical prediction models has been validated against American Society for Testing and Materials (ASTM) standards, demonstrating their capability to deliver precise real-time property values. This approach not only enhances the efficiency of refinery analysis but also sets a new standard for the monitoring and optimization of heavy oil processing in real-time approach., (© 2024. The Author(s), under exclusive licence to The Japan Society for Analytical Chemistry.)

This study focuses on addressing the challenges in the dry reforming of propane, a process historically marked by low syngas yields and only moderate conversions of CO 2 and propane. The primary objective was to enhance CO 2 utilization and boost the selectivity of syngas (CO and H 2 ) production using titania-based catalysts. For synthesizing these catalysts, an impregnation method was employed with subsequent characterization through X-ray diffraction (XRD), N 2 adsorption-desorption, ammonia temperature-programmed desorption (TPD), and hydrogen temperature-programmed reduction (TPR). The titania-based catalysts generally possess weak acidic strength, with each catalyst displaying a unique reduction profile. The dry reforming process using these catalysts resulted in varying levels of propane conversion, with V/Ti, Ir/Ti, Al/Ti, and Zr/Ti catalysts showing distinct efficiencies. Notably, the Ir/Ti and V/Ti oxide catalysts achieved the lowest selectivity for generating intermediate byproducts such as methane, ethane, ethylene, and propylene while successfully promoting higher syngas CO and H 2 production alongside stable propane conversion. When exposed to excess CO 2 , each catalyst consumed differing amounts of CO 2 molecules. Particularly, the Ir/Ti and V/Ti oxide catalysts demonstrated enhanced activity in promoting CO 2 reactions with intermediate radical species, facilitating carbon-carbon (C-C) bond dissociation and leading to increased syngas production. This study offers valuable insights into the potential of titania-based catalysts in improving the efficiency and selectivity of propane dry reforming processes for blue hydrogen., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Closed gastroschisis is a rare entity usually associated with intestinal atresia and short bowel syndrome. We report two cases of closed gastroschisis presenting with neonatal intestinal obstruction and para-umbilical evisceration without an abdominal defect.

Background: Inflammatory bowel disease (IBD) is increasingly encountered in children. Early disease is associated with higher complication rate with increased incidence of surgical intervention., Patients and Methods: From January 2010 to June 2015, 25 patients in the pediatric and adolescent age groups with IBD underwent surgical intervention in our center. They were classified into two groups. Group I included 15 patients with ulcerative colitis where 5 cases had left colon disease underwent left colectomy, while 10 cases had pancolonic disease underwent total colectomy and anal mucosectomy with ileo-anal or ileal pouch-anal anastomosis with covering ileostomy. Group II included 10 cases with Crohn's disease where the indications for surgery were intestinal obstruction in seven cases, fulminant perianal infection with septic shock in one, perianal fistula and ulcers in one, and growth failure due to resistant intestinal fistula in one., Results: Group I included eight males and seven females; mean age at surgery was 10.6 years. There were postoperative complications in seven cases in the form of pelvic abscess and wound infection in one, wound infection in two, and recurrent pouchitis in four cases. Group II contained eight males and two females; mean age at surgery was 6.6 years. Two cases had recurrent symptoms after stricturoplasty. The mean length of time from diagnosis to surgery was 2.4 years (ranging from 6 to 36 months)., Conclusion: A multidisciplinary team is mandatory for proper management of IBD cases. The risk of the disease and the expected surgical complications determine the timing of surgical interference.

Purpose: To define the characteristic radiological features following colonic replacement of the esophagus in children., Materials and Methods: The upper gastro-intestinal contrast studies of 43 patients who underwent colonic replacement of the esophagus at our pediatric surgery unit were available for analysis. UGI contrast studies were performed routinely in the post-surgical period in 17 cases (first asymptomatic group), while the rest of contrast studies (26) belonged to a second group of out-patients complaining of dysphagia (18) or dyspepsia (8) following colonic replacement of the esophagus. Based on our observations, we proposed a grading system to describe the degree of colonic redundancy in the thorax., Results: Redundancy of the colonic conduit in the thoracic cavity was a common radiological finding (62.8%). The redundancy was mild (grade 1) in 18 patients, moderate (grade 2) in eight, and severe (grade 3) in only one patient. In 88.9%, the redundancy was in the right hemi-thorax. Patients presenting with postoperative dysphagia had a stricture at the site of the esophago-colic anastomosis in the neck, which should be differentiated from other sites of anatomical narrowing at the inlet and outlet of the thoracic cavity. Gastro-colic reflux was common among patients who underwent colonic replacement of the esophagus without an anti-reflux procedure., Conclusion: Colonic replacement of the esophagus in children results in considerable anatomical alterations. Knowledge about the normal post-surgical changes and imaging features of the commonly encountered complications can increase the diagnostic confidence among radiologists and clinicians when dealing with these cases., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)