OPTIMIZATION OF A PROCESS FOR DISCOLORATION OF LOW-GRADE SYRUP

L'amélioration de la couleur du sirop industriel de qualité inférieure, sur le charbon actif, a été optimisée à l'aide d'une conception composite centrale et d'une méthodologie de surface de réponse. Cette étude vérifie l'effet de trois paramètres expérimentaux : masse d'adsorbant (charbon actif), temps de contact adsorbat-adsorbant (sirop - charbon actif), rapport de masses des farines constituant le gâteau de filtration (m w /m b ) , et leurs interactions sur la réponse : ICUMSA Color. L'exploitation du modèle établi dans l'espace des variables a permis de définir des conditions économiques optimales d'obtention de sirop de classe claire selon la Commission Internationale pour les Méthodes Uniformes d'Analyse du Sucre (ICUMSA)

Advanced statistical optimization of parameters of synthesis process of oxygenated carbonated apatite

International audienceThe synthesis process of oxygenated carbonated apatite was optimized by an advanced statistical planning of experiments. Full factorial design of 24 experiments was used to find the effects of five principal parameters: pH of the reaction medium, atomic ratio Ca/P of the reagents, concentration of the calcium solution (Ca2+), temperature of the reaction medium (T) and duration of the reaction (D), with fixing the H2O2 composition at 30% and stirring to 600 turns/min. Studied responses were the atomic ratio Ca/P, % O2, % O2 2− and % CO3 2−. Optimum synthesis parameters were found to be pH = 7.38, Ca/P = 1.647, [Ca2+] = 0.636 M, T = 40°C and D = 1 h. The prediction responses were Ca/P = 1.575, % O2 = 0.76, % O2 2− = 0.50 and % CO3 2−= 1.84. The actual experimental results were in agreement with the prediction

Synthesis, characterization and thermal behaviour of a Phosphocalcic Oxygenated Apatite

A new route for preparing an antiseptic biomaterial has been described. An oxygenated apatite-based calcium phosphate powder that had a Ca/P ratio of 1.55 was synthesized from calcium nitrate and phosphoric acid in oxygenated water via a precipitation method. The X-ray diffraction and FTIR analysis of the as-dried powder reveals that the apatite is poorly crystalline and is converted into a biphasic calcium phosphate (HAP/beta TCP) when calcined at a temperature higher than 600°C. The chemical analysis of oxygenated species shows the disappearance of these species at 400°C

Cardiac risk after elective endovascular repair for infrarenal abdominal aortic aneurysm: Results from the Italian Collaborators for EVAR multicenter registry

Objective: Major adverse cardiac events (MACEs) were common complications after endovascular aortic repair (EVAR) causing significant postoperative morbidity and mortality. The aim of the study was to evaluate the cardiac risk after elective EVAR for uncomplicated noninfected infrarenal abdominal aortic aneurysm in a large multicenter cohort. Methods: This is a multicenter, retrospective, financially unsupported physician-initiated observational cohort study conducted by four academic tertiary referral hospitals from January 2018 to March 2021. Baseline, perioperative, and postoperative information of elective EVARs was evaluated. The primary outcome was the incidence of MACEs after EVAR, which was defined as acute coronary syndrome, non-ST-elevation myocardial infarction, unstable angina pectoris, de novo atrial fibrillation, hospitalization for heart failure, and revascularization as well as cardiovascular death. Secondary outcomes were 1-year overall survival (all-cause mortality) and freedom from aorta-related mortality. Comparative analysis was conducted between MACE and overall population, and univariate and multivariate logistic regression analyses were used to analyze factors associated with the risk of the MACE occurrence and early 1-year mortality. Results: The study has enrolled 497 patients (35 females, 7%) with a mean age of 75.3 ± 7.8 years. The MACE rate was 6.4% (32/497, events/patients), and the majority of the events were recorded in the postoperative period (24/32, 75%; overall 24/497, 4.8%). One-year survival from all-cause mortality was 94% (95% confidence interval [CI]: 91-96), and the MACE population showed a significantly lower survival estimation rate (Overall - MACEs, 95.8% [95% CI: 93-97] - 67.9% [95% CI: 47-82], log-rank 41.950, P =.0001). Freedom from aorta-related mortality was 99.3% (95% CI: 98-100). The perioperative need for red blood cell transfusions was strongly related to the MACE occurrence (odds ratio: 2.67, 95% CI: 1.52-4.68, P =.001) and 1-year mortality (hazard ratio: 2.14, 95% CI: 1.48-3.09, P =.0001). Conclusions: MACEs represent a common complication in the postoperative and early period after elective EVAR. Blood loss requiring red blood cell transfusions is associated with increased postoperative MACEs and early mortality, suggesting that all the efforts should be carried out to reduce the bleeding during and after elective interventions