This study investigated the mechanical behavior of normal strength (NS) and high strength (HS) concrete containing recycled fine aggregates (RFAs). A high slump mixing design was employed, which may be potentially used as filled structural concrete. The compressive strength, tensile strength, and elastic modulus were measured according to the RFA replacement ratio and curing time. In addition, the shrinkage strain was measured in a temperature and humidity chamber over 260 days. The compressive strength and elastic modulus of RFA concrete were approximately 70–90% of those of virgin concrete. The decreases in the compressive strength and elastic modulus for NS concrete were larger than those for HS concrete. This could be explained by the difference in failure mechanism between NS and HS concrete. The average ratio of the compressive strength at 190 days to that at 28 days was 1.15–1.3, and the ratio of the tensile strength at 190 days to that at 28 days was 1.15–1.25. These demonstrate good strength development. The ratios between the elastic modulus and compressive strength for RFA concrete were dissimilar to those for virgin concrete but similar to those for recycled coarse aggregate concrete. ACI 318-14 (Building code requirements for structural concrete and commentary, 2014) and Model Code (Fib model code for concrete structures, 2010) overestimated the elastic modulus of RFA concrete. Therefore, this study suggested an empirical expression to approximate the elastic modulus of RFA concrete. The increase in shrinkage owing to the use of RFA was at most 5–6% of the ultimate compressive strain of concrete.

We report the solution processed polycrystalline InGaZnO thin film transistor. The films with molar ratio of In, Ga, and Zn (1: 1: 2) were deposited by spin coating, and the device exhibits an on-to-off current ratio of ~1.88ⅹ10 5 and field effect mobility of ~0.96 cm 2 /Vs, respectively.

Splenic infarction is an unusual cause for a patient to present with left upper abdomen pain. A 47-year-old woman presented to the emergency department with left upper abdomen pain. She reported that she stopped taking warfarin two days prior to presentation. A physical examination revealed fine crackles within the left lower lobe and significant tenderness within the left upper abdomen. Computed tomography of the abdomen showed mild cardiomegaly with a 2.3 cm calcified thrombus in the left ventricular apex. We noted infarction in the spleen and right kidney with bilateral renal scarring. The patient was initially started on a heparin drip and later bridged to warfarin on the third day. She was discharged after seven days with complete resolution of the abdominal pain. The decision to prescribe an anticoagulant should include a consideration of underlying causes, comorbidities, an assessment of risks and benefits, and chances of recurrence. In our patient, her new splenic infarct and renal infarction were most likely embolic in origin due to her left ventricular apical aneurysm with thrombus and nonadherence to her prescribed anticoagulation medication.

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Digoxin is rarely used in modern cardiovascular disease management. Therefore, digoxin toxicity has been infrequently encountered and it is paramount to diagnose in a timely fashion. Bidirectional ventricular tachycardia is an unusual arrhythmia wherein every other beat has a different QRS axis as it travels alternately down different conduction pathways. The arrhythmia can be a manifestation of myocarditis, myocardial infarct, Andersen-Tawil syndrome, arrhythmogenic right ventricular cardiomyopathy, catecholaminergic polymorphic ventricular tachycardia, herbal aconite poisoning, and digoxin toxicity. This case illustrates the importance of clinician awareness of rare electrocardiogram (EKG) patterns of digoxin toxicity and visual resolution of fatal arrhythmia with timely treatment.

This is a case of a 77-year-old woman who underwent a multiple-gated acquisition (MUGA) scan to evaluate her cardiac function after initially presenting with chest pain and shortness of breath. The scan revealed the presence of an apicoaortic conduit (AAC) and incidentally found a left ventricular pseudoaneurysm. After aneurysmectomy, the MUGA scan was repeated.

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Introduction:Myocarditis is a disease that has varying degrees of clinical manifestations. Furthermore, its diagnosis and management can pose as a challenge to clinicians. With over 250 million people receiving the mRNA covid vaccine, there have been rare reports of myocarditis, pericarditis or other cardiovascular involvement. However, its natural course remains unclear. Case:We report a 30-year-old healthy male who was hospitalized 3 days after the second dose of the covid-19 vaccination. He had high cardiac laboratory markers (cardiac troponin I peak of 22 ng/mL, normal <0.03 ng/mL). He had a subsequent coronary angiogram and echocardiogram that were normal and was hence diagnosed with myocarditis. After week 3, his symptoms fully abated along with all of his inflammatory and cardiac markers. He had a cardiac magnetic resonance (CMR) study 8 weeks later (from the date of his vaccine dose) that showed prominent mid to epicardial lateral wall fibrosis with normal T1 and T2 mapping. A repeat CMR was performed 3 months later, which is almost 22 weeks since the vaccine administration. It showed persistent, though partially resolving fibrosis, despite full resolution of symptoms and biomarkers, demonstrating an insidious recovery. Conclusion:This case demonstrates myocarditis following the second dose of the mRNA covid-19 vaccination with evidence of myocardial fibrosis on CMR and on follow-up CMR scan nearly 5 and a ½ months from administration. Furthermore, it shows remaining evidence of myocardial fibrosis despite the normalization of symptoms and traditional screening methods such as echocardiography and the use of cardiac and inflammatory biomarkers in disease surveillance. It provides insight into its natural course and insidious recovery as well as the utility of CMR in clinical management.