Patent foramen ovale (PFO) is a common congenital abnormality of the heart. It results from incomplete closure of foramen ovale that persists in adulthood. Most individuals with PFO are asymptomatic and are discovered incidentally. The left atrial pressure is generally higher than the right atrial pressure, which prevents blood flow against the gradient; however, any medical condition that increases the pulmonary artery pressure can lead to reversal of blood flow from right to left by elevating right atrial pressure. We present a case of a 59-year-old female who presented with complaints of shortness of breath associated with bilateral lower-extremity edema and was found to have acute decompensated heart failure and atrial fibrillation. Transesophageal echocardiogram (TEE) with cardioversion was performed. Propofol was given for conscious sedation; however, the procedure was terminated as patient became hypoxemic and was noted to have moderately dilated right ventricle (RV) with hypokinesia and PFO with right-to-left shunting. It also demonstrated mild mitral regurgitation, mild left ventricular hypertrophy, and a left ventricular ejection fraction of 55-60%. In contrast to TEE findings, while the patient was having normal oxygen saturation, transthoracic echocardiogram showed left-to-right shunting instead of right-to-left and no RV hypokinesia was noted. In conclusion, this case draws attention to the relationship between acute hypoxemia and rightto-left shunting in a patient with PFO. This case illustrates and highlights the need for more prospective studies to establish a relationship between acute hypoxemia and right-to-left shunting in the presence of PFO.

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The phenomenon of dumping used tires in Kuwait has reached critical levels, with a landfill containing millions of tires being formed in a remote area, which is a major environmental hazard. Nowadays, recycled rubber is used as a suitable and useful material in civil engineering applications, particularly in the production of “green concrete”. This study aims to see whether recycled tire by-products can be used to make “green concrete” for pavements. Each type of tire by-product was tested individually to examine its properties and effects on a benchmark mix before creating hybrid mixes that contain a combination of the materials. Eleven mixes containing different doses of shredded or crumbed rubber or steel fibers contained within the tires were made to evaluate their impact on the concrete’s slump, compressive strength, split tensile strength, and modulus of rupture. Additionally, twelve hybrid concrete mixes containing different doses of various tire by-products were developed. Preliminary results show that the incorporation of rubber products has a reduction on the concrete’s properties. The use of replacement materials sourced from recycled tires using the dosages investigated in this study does not detract from the usability of green pavement concrete suited for hot weather. The concrete produced in this study could be evaluated for specific properties relating to its road safety in further studies. Additionally, long-term effects of using the concrete can be studied using finite element analysis.

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