Removal of hexavalent chromium and pentavalent arsenic from aqueous solutions by adsorption on polyethylenimine-modified silica nanoparticles.

Chromium and arsenic are commonly found in water and wastewater as hexavalent chromium, Cr(VI), and inorganic arsenic species, such as pentavalent arsenic, As(V). In aqueous media, both Cr(VI) and As(V) exist predominantly in the form of oxy-anions. In our study, we prepared a polyethylenimine-silica composite material (SiO₂-PEI) as an adsorbent to study the adsorption capacity for chromate and arsenate ions.

Long-Term Outcomes of Aortic Stenosis Patients with Different Flow/Gradient Patterns Undergoing Transcatheter Aortic Valve Implantation.

Few data exist on the comparative long-term outcomes of severe aortic stenosis (AS) patients with different flow-gradient patterns undergoing transcatheter aortic valve implantation (TAVI). This study sought to evaluate the impact of the pre-TAVI flow-gradient pattern on long-term clinical outcomes after TAVI and assess changes in the left ventricular ejection fraction (LVEF) of different subtypes of AS patients following TAVI. Consecutive patients with severe AS undergoing TAVI in our institution were screened and prospectively enrolled.

Chromium(VI) Removal from Water by Lanthanum Hybrid Modified Activated Carbon Produced from Coconut Shells.

Cr(VI) is considered to be the most hazardous and toxic oxidation state of chromium and hence the development of effective removal technologies, able to provide water with Cr(VI) below the drinking water limits (US EPA 100 μg/L, European Commission 50 μg/L, which will be reduced to 25 by 2036) is a very important issue in water treatment. This study aimed at examining the performance of activated carbon produced from coconut shells, modified by lanthanum chloride, for Cr(VI) removal from waters. The structure of the formed material (COC-AC-La) was characterized by the application of BET, FTIR and SEM techniques.

Long-Term Outcomes and Valve Performance in Patients Undergoing Transcatheter Aortic Valve Implantation.

Transcatheter aortic valve implantation (TAVI) is an established method for treating patients with aortic valve stenosis. We sought to determine the long-term clinical outcomes and performance of a self-expanding bioprosthesis beyond 5 years. Consecutive patients scheduled for TAVI were included in the analysis.

One-year clinical and echocardiographic outcomes of direct implantation of a self-expanding valve.

Objective: To present 1 year clinical and echocardiographic outcomes of the randomized DIRECT (Pre-dilatation in Transcatheter Aortic Valve Implantation Trial) trial.

Background: Intermediate-term data from randomized studies investigating the safety and efficacy of direct implantation are lacking.

Methods: DIRECT trial randomized 171 consecutive patients with severe aortic stenosis at four tertiary centers to undergo TAVI with the use of self-expanding prostheses with (pre-BAV) or without pre-dilatation (no-BAV).