Subsurface oxygen defects electronically interacting with active sites on In2O3 for enhanced photothermocatalytic CO2 reduction.

Oxygen defects play an important role in many catalytic reactions. Increasing surface oxygen defects can be done through reduction treatment. However, excessive reduction blocks electron channels and deactivates the catalyst surface due to electron-trapped effects by subsurface oxygen defects. How to effectively extract electrons from subsurface oxygen defects which cannot directly interact with reactants is challenging and remains elusive. Here, we report a metallic In-embedded In2O3 nanoflake catalyst over which the turnover frequency of CO2 reduction into CO increases by a factor of 866 (7615 h-1) and 376 (2990 h-1) at the same light intensity and reaction temperature, respectively, compared to In2O3. Under electron-delocalization effect of O-In-(O)Vo-In-In structural units at the interface, the electrons in the subsurface oxygen defects are extracted and gather at surface active sites. This improves the electronic coupling with CO2 and stabilizes intermediate. The study opens up new insights for exquisite electronic manipulation of oxygen defects.

Severe Prinzmetal's Angina Inducing Ventricular Fibrillation Cardiac Arrest.

Prinzmetal's angina is a vascular spasm of the coronary artery that can mimic acute coronary syndrome. It is rarely responsible for ventricular arrhythmias and cardiac arrest; however, survivors with these complications are at increased risk for recurrent ventricular arrhythmias and sudden cardiac death. This is true despite the presence of normal cardiac function and optimal medical therapy. Thus, this select population should be considered for an implantable cardioverter defibrillator (ICD). In this case vignette, we describe a healthy 48-year-old female with ventricular fibrillation arrest, followed by recurrent ventricular tachyarrhythmias caused by Prinzmetal's angina.

Broadband dispersion-free optical cavities based on zero group delay dispersion mirror sets.

A broadband dispersion-free optical cavity using a zero group delay dispersion (zero-GDD) mirror set is demonstrated. In general zero-GDD mirror sets consist of two or more mirrors with opposite group delay dispersion (GDD), that when used together, form an optical cavity with vanishing dispersion over an enhanced bandwidth in comparison with traditional low GDD mirrors. More specifically, in this paper, we show a realization of such a two-mirror cavity, where the mirrors show opposite GDD and simultaneously a mirror reflectivity of 99.2% over 100 nm bandwidth (480 nm - 580 nm).

Rapid correction of hypokalemia in a patient with an implantable cardioverter-defibrillator and recurrent ventricular tachycardia.

We present the case of a 74-year-old man with non-ischemic dilatated cardiomyopathy and an implantable cardioverter-defibrillator presenting with a serum potassium of 2.6 mmol/L, recurrent unstable ventricular tachycardia, and multiple defibrillations. Administration of a rapid bolus of 20 mEq KCL solution via central venous access, followed by an additional total of 80 mEq (orally and intravenously [i.v.]) over the next 2 h, resulted in immediate resolution of his recurrent unstable dysrhythmia without toxic side effects. Guidelines for rapid correction of hypokalemia quote a maximum safe administration of 20 mEq i.v./h. In addition to discussing the clinical relevance and physiologic interactions of the variables leading to this patient's presentation, we discuss the successful termination of his sustained recurrent ventricular dysrhythmia by rapid potassium repletion above currently recommended rates. The patient we present is representative of a growing population, given medical and technological advances over the years. Potassium boluses may be reasonable in such circumstances, particularly in patients with ICDs.

Giant colonic diverticulum: percutaneous computed tomography-guided treatment.

We present a case of inflamed giant sigmoid diverticulum, which was treated under computed tomographic guidance by dilating the neck and decompressing the inflamed diverticulum. The procedure also involved placement of an internal stent across the neck of the diverticulum, the purpose of which was to decompress the giant diverticulum into the sigmoid colon and prevent acute recurrence. In patients with inflamed giant colonic diverticulum, the percutaneous approach may be useful in treatment of diverticulitis and avoiding a staged Hartmann procedure with end colostomy.