757 research outputs found
Biosorption mechanism of Methylene Blue from aqueous solution onto White Pine (Pinus durangensis) sawdust: Effect of operating conditions
In this work, the biosorption mechanism of the cationic dye Methylene Blue (MB) on natural White Pine
sawdust (NS) (Pinus durangensis) was investigated. Likewise, the surface charge distribution of NS was
determined, and its point of zero charge was found to be 4.3. Besides, the capacity of the NS for adsorbing
MB was increased 1.7, 2.0 and 4.6 times when the pH was raised from 3 to 4.25, 3 to 7 and 3 to 10,
respectively. This behavior was attributed to the electrostatic attraction between the negatively charged
surface of NS and the cationic species MBĂŸ. The adsorption capacity increased with increased temperature
because the adsorption was an endothermic process. The adsorption capacity was drastically
reduced by increasing the ionic strength of the solution corroborating with the fact that the electrostatic
attractions played a crucial role in the adsorption of MB on NS. It was also shown that the MB was
chemisorbed because the adsorption was not reversible. The predominant adsorption mechanisms were
the electrostatic attraction and chemisorption and not ion exchange.This work was funded by the Consejo Nacional de Ciencia y
Tecnologia, CONACyT, Mexico, through grants: CONAFOR-2010-
C02-148302 and CB-2012-02-182779
Psychological and Sleep Effects of Tryptophan and Magnesium-Enriched Mediterranean Diet in Women with Fibromyalgia
Anxiety, mood disturbance, eating and sleep disorders, and dissatisfaction with body image are prevalent disorders in women with fibromyalgia. The authors of this study aimed to determine the effects of tryptophan (TRY) and magnesium-enriched (MG) Mediterranean diet on psychological variables (trait anxiety, mood state, eating disorders, self-image perception) and sleep quality in women with fibromyalgia (n = 22; 49 ± 5 years old). In this randomized, controlled trial, the participants were randomly assigned to the experimental group and the placebo group. The intervention group received a Mediterranean diet enriched with high doses of TRY and MG (60 mg of TRY and 60 mg of MG), whereas the control group received the standard Mediterranean diet. Pittsburgh Sleep Quality Questionnaire, Body Shape Questionnaire, StateâTrait Anxiety Inventory (STAI), Profile of Mood States (POMS-29) Questionnaire, Eating Attitudes Test-26, and Trait Anxiety Inventory were completed before and 16 weeks after the intervention. Significant differences were observed between groups after the intervention for the mean scores of trait anxiety (p = 0.001), self-image perception (p = 0.029), mood disturbance (p = 0.001), and eating disorders (p = 0.006). This study concludes that tryptophan and magnesium-enriched Mediterranean diet reduced anxiety symptoms, mood disturbance, eating disorders, and dissatisfaction with body image but did not improve sleep quality in women with fibromyalgia
Confined Pt11+ Water Clusters in a MOF Catalyze the LowâTemperature WaterâGas Shift Reaction with both CO2 Oxygen Atoms Coming from Water
The synthesis and reactivity of single metal atoms in a lowâvalence state bound to just water, rather than to organic ligands or surfaces, is a major experimental challenge. Herein, we show a gramâscale wet synthesis of Pt11+ stabilized in a confined space by a crystallographically wellâdefined first water sphere, and with a second coordination sphere linked to a metalâorganic framework (MOF) through electrostatic and Hâbonding interactions. The role of the water cluster is not only isolating and stabilizing the Pt atoms, but also regulating the charge of the metal and the adsorption of reactants. This is shown for the lowâtemperature waterâgas shift reaction (WGSR: CO + H2O â CO2 + H2), where both metal coordinated and Hâbonded water molecules trigger a double water attack mechanism to CO and give CO2 with both oxygen atoms coming from water. The stabilized Pt1+ single sites allow performing the WGSR at temperatures as low as 50â°C.This work was supported by the MINECO (Spain) (Projects CTQ2016â75671âP, MAT2013 40823âR, MAT2016â81732âERC, CTQ2017â86735âP, MAT2017â86992âR, MAT2017â82288âC2â1âP and Excellence Units âSevero Ochoaâ and âMaria de Maeztuâ SEVâ2016â0683 and MDMâ2015â0538) the Generalitat Valenciana (PROMETEOII/2014/004) and the Ministero dellâIstruzione, dellâUniversitĂ e della Ricerca (Italy) and the Junta de AndalucĂa (FQMâ195). M. M. and M.âA. R. C. thanks the MINECO for a predoctoral contract. Thanks are also extended to the RamĂłn y Cajal Program (E. V. R.âF., E. P. and J.âC. H.âG.) and the âSubprograma atracciĂł de talentâcontractes postdoctorals de la Universitat de Valenciaâ (J. F.âS.). M. L.âH. acknowledges the financial support from the Juan de la Cierva Fellowships Program of MINECO (IJCIâ2014â19367)
Alternative Eco-Friendly Methods in the Control of Post-Harvest Decay of Tropical and Subtropical Fruits
The effectiveness on several fruits by the application of alternative methods against fungi is summarized in the present chapter. Several investigations have reported the efficacy of these technologies for controlling fungal infections. Currently, high post-harvest loses have been reported due to several factors such as inefficient management, lack of training for farmers, and problems with appropriate conditions for storage of fruits and vegetables. Even now, in many countries, post-harvest disease control is led by the application of chemical fungicides. However, in this time, awareness about fungi resistance, environmental, and health issues has led to the research of eco-friendly and effective alternatives for disease management. The pathogen establishment on fruits can be affected by the application of GRAS compounds like chitosan, essential oils, salts, among others; besides, their efficacy can be enhanced by their combination with other technologies like ultrasound. Thus, the applications of these alternatives are suitable approaches for post-harvest management of fruits
Constitutive modelling of skin ageing
The objective of this chapter is to review the main biomechanical and structural aspects associated with both intrinsic and extrinsic skin ageing, and to present potential research avenues to account for these effects in mathematical and computational models of the skin. This will be illustrated through recent work of the authors which provides a basis to those interested in developing mechanistic constitutive models capturing the mechanobiology of skin across the life course
Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).
Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and â„1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (nâ=â5069) or prospectively (nâ=â5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (â€6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; pâ=â0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)
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