Iron-Iron Oxide Core-Shell Nanochains as High-Performance Adsorbents of Crystal Violet and Congo Red Dyes from Aqueous Solutions.

The main aim of this work was to use the iron-iron oxide nanochains (Fe NCs) as adsorbents of the carcinogenic cationic crystal violet (CV) and anionic Congo red (CR) dyes from water. The investigated adsorbent was prepared by a magnetic-field-induced reduction reaction, and it revealed a typical core-shell structure. It was composed of an iron core covered by a thin Fe3O4 shell (<4 nm). The adsorption measurements conducted with UV-vis spectroscopy revealed that 15 mg of Fe NCs constituted an efficient dose to be used in the CV and CR treatment. The highest effectiveness of CV and CR removal was found for a contact time of 90 min at pH 7 and 150 min at pH 8, respectively. Kinetic studies indicated that the adsorption followed the pseudo-first-order kinetic model. The adsorption process followed the Temkin model for both dyes taking into account the highest value of the R2 coefficient, whereas in the case of CR, the Redlich-Peterson model could be also considered. The maximal adsorption capacity estimated from the Langmuir isotherms for the CV and CR was 778.47 and 348.46 mg g-1, respectively. Based on the Freundlich model, both dyes adsorbed on the Fe NCs through chemisorption, but Coulombic interactions between the dye and adsorbent cannot be excluded in the case of the CV dye. The obtained results proved that the investigated Fe NCs had an excellent adsorption ability for both dye molecules within five cycles of adsorption/desorption, and therefore, they can be considered as a promising material for water purification and environmental applications.

Green composites based on volcanic red algae Cyanidiales, cellulose, and coffee waste biomass modified with magnetic nanoparticles for the removal of methylene blue.

In this paper, green nanocomposites based on biomass and superparamagnetic nanoparticles were synthesized and used as adsorbents to remove methylene blue (MB) from water with magnetic separation. The adsorbents were synthesized through the wet co-precipitation technique, in which iron-oxide nanoparticles coated the cores based on coffee, cellulose, and red volcanic algae waste. The procedure resulted in materials that could be easily separated from aqueous solutions with magnets. The morphology and chemical composition of the nanocomposites were characterized by SEM, FT-IR, and XPS methods. The adsorption studies of MB removal with UV-vis spectrometry showed that the adsorption performance of the prepared materials strongly depended on their morphology and the type of the organic adsorbent. The adsorption studies presented the highest effectiveness in neutral pH with only a slight effect on ionic strength. The MB removal undergoes pseudo-second kinetics for all adsorbents. The maximal adsorption capacity for the coffee@Fe3O4-2, cellulose@Fe3O4-1, and algae@Fe3O4-1 is 38.23 mg g-1, 41.61 mg g-1, and 48.41 mg g-1, respectively. The mechanism of MB adsorption follows the Langmuir model using coffee@Fe3O4 and cellulose@Fe3O4, while for algae@Fe3O4 the process fits to the Redlich-Peterson model. The removal efficiency analysis based on UV-vis adsorption spectra revealed that the adsorption effectiveness of the nanocomposites increased as follows: coffee@Fe3O4-2 > cellulose@Fe3O4-1 > algae@Fe3O4-1, demonstrating an MB removal efficiency of up to 90%.

Higher milk consumption is not associated with fracture risk reduction: systematic review and meta-analysis.

INTRODUCTION: Osteoporosis affects over 200 million people worldwide causing nearly 9 million fractures annually, with more than half in America and Europe. OBJECTIVES: This meta-analysis was conducted to investigate whether low milk intake is associated with an increased risk of fractures by summarizing all the available evidence. METHODS: Relevant studies were identified by searching the PubMed and EMBASE databases up to June 2020. The pooled relative risks with 95% confidence intervals were calculated. RESULTS: In a meta-regression analysis of 20 included studies (11 cohort and 9 case-control studies), a higher milk intake was not associated with a reduction in the total fracture risk in both sexes (OR 0.95, 95% CI: 0.84- 1.08), either in cohort (OR 0.91; 95% CI: 0.79-1.05) or case-control studies (OR 1.09; 95% CI: 0.82-1.44), as well as separately in men (OR 0.87; 95% CI: 0.71-1.07) and women (OR 0.95; 95% CI: 0.80-1.13). CONCLUSION: Higher milk consumption is not associated with fracture risk reduction and should not be recommended for fracture prevention.

Usefulness of scoring systems in outcome prediction for older cancer patients undergoing abdominal surgery.

BACKGROUND: Several postoperative outcome scoring systems have been developed and validated, combining both pre- and intraoperative factors. Among others are the Portsmouth Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity (P-POSSUM), the Estimation of Physiologic Ability and Stress (E-PASS) and the Surgical Apgar Score combined with the American Society of Anesthesiologists physical status classification (SASA). The aim of this study was to compare the above scoring systems in the prediction of 30-day postoperative outcome in older patients with cancer undergoing abdominal surgery. METHODS: Consecutive patients ≥70 years were prospectively enrolled. Pre- and intraoperative variables were used to calculate the scores, the ROC and perform logistic regression analysis. RESULTS: The study sample comprised 201 patients with a median age of 77 (range 70-93) years. The most common surgical procedure was for colorectal (75%), followed by gastric (10.4%) pancreas (7.0%), gall bladder (3.5%), small bowel (2.5%), and other (1.5%) types of cancer. All scores were independent predictors of 30-day postoperative mortality. In case of 30-day morbidity only SASA turned to be significant. The ROC curves were highly valid and area under the curve showed fair to good discriminatory ability (0.60-0.77) for 30-day postoperative mortality and fair (AUC 0.6) in case of SASA for the 30-day postoperative. CONCLUSION: The SASA, E-PASS, and P-POSSUM were confirmed to be predictive of 30-day postoperative mortality in older patients undergoing abdominal elective cancer surgery. Only SASA demonstrated as independent factor predicting postoperative 30-day major morbidity.