Folate and folic acid intake estimation and food enrichment requirements

The term "folate" is a generic way to name the different forms derived from folic acid, one of the B vitamins (specifically B9 vitamin). They are essential in the metabolism when they act as cofactors in the transfer reactions of one carbon. However, only plants and microorganisms are able to synthesize them de novo, in such a way that both animals and human beings have to intake them through their diet. Folic acid is widely spread in nature, mainly in vegetables, liver ans cereals. However, nowadays, the lack of folates in the diet is one of the most common nutritional deficiencies in the world, and it has serious consequences on human health. There is evidence that even in developed countries folate intake is usually low; and even, is some cases, below optima levels. The authorities in several countries have adapted different norms related to folic acid, fortifying staple food such as dairy products or cereals, mandatory (U.S.A., Canada or Chile) or voluntary (most of the European countries).     

Preparation and in situ characterization of surfaces using soft landing in a Fourier transform ion cyclotron resonance mass spectrometer

Mass-selected peptide ions produced by electrospray ionization were deposited onto fluorinated self-assembled monolayer surfaces (FSAM) surfaces by soft landing using a Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS) specially designed for studying interactions of large ions with surfaces. Analysis of the modified surface was performed in situ by combining 2-keV Cs+ secondary ion mass spectrometry with FT-ICR detection of the sputtered ions (FT-ICR-SIMS). Regardless of the initial charge state of the precursor ion, the SIMS mass spectra included singly protonated peptide ion, peptide fragment ions, and peaks characteristic of the surface in all cases. In some experiments, multiply protonated peptide ions and [M + Au]+ ions were also observed upon SIMS analysis of modified surfaces. For comparison with the in situ analysis of the modified surfaces, ex situ analysis of some of the modified surfaces was performed by 25-keV Ga+ time-of-flight-secondary ion mass spectrometry (TOF-SIMS). The ex situ analysis demonstrated that a significant number of soft-landed peptide ions remain charged on the surface even when exposed to air for several hours after deposition. Charge retention of soft-landed ions dramatically increases the ion yields obtained during SIMS analysis and enables very sensitive detection of deposited material at less than 1% of monolayer coverage. Accumulation of charged species on the surface undergoes saturation due to coulomb repulsion between charges at close to 30% coverage. We estimated that close to 1 ng of peptide could be deposited on the spot area of 4 mm2 of the FSAM surface without reaching saturation.     

Impregnated active carbons to control atmospheric emissions: influence of impregnation methodology and raw material on the catalytic activity

Previous studies have reported the influence of raw material on the catalytic activity of metal oxides impregnated in activated carbons. However, knowledge was as yet quite scarce for impregnation performed before activation. The main objective of the study here reported was the development of such knowledge. Olive stones, pinewood sawdust, nutshells, and almond shells were recycled to prepare the activated carbons. Transition metal oxides (CoO, Co3O4, and CrO3) were impregnated aiming to prepare activated carbons to be used for the complete catalytic oxidation of benzene. When impregnation was performed after activation the impregnated species were deposited on the internal surface, blocking part of the initial porous texture. When impregnation was performed before activation, the metal species acted as catalysts during the activation step, allowing better catalyst distribution on a more well-developed mesoporous texture. Co3O4 was the best catalyst and almond shells were the best support. With this catalyst/support pair a conversion of 90% was possible at 404 K, the lowest temperature of all the carbons studied. Good conversions were obtained at temperatures that guarantee carbon stability (lower than 575 K). It was concluded that activated carbon was a suitable support for metal oxide catalysts aiming for the complete oxidation of benzene, especially when a suitable porous texture is induced, by performing the impregnation step before activation.     

Effect of a postoperative exercise program on arteriovenous fistula maturation: A randomized controlled trial

Exercises after arteriovenous fistula (AVF) creation may help to improve maturation; however, their usefulness has only been examined in indirect, non‐comparative studies or small trials. Between June 2013 and November 2014, we included all ambulatory patients with stages 5‐5D chronic kidney disease who were candidates for the creation of a native AVF in our center. After surgery, all patients were randomized to an exercise group or a control group with single‐blind control. At 1 month postoperatively, clinical maturation (expert nurse inspection) and ultrasonographic maturation (flow >500 mL/min, venous diameter >5 mm and depth <6 mm) were assessed in all patients. A total of 72 patients were randomized, 3 were lost to follow‐up, and 69 were finally analyzed. The mean age was 66.8 years (standard deviation 13.8), 70.0% were men, and 65.2% were in pre‐dialysis. After surgery (42.0% had distal AVF), the patients were randomized (31 controls, 38 exercise group). At 1 month after surgery, global clinical and ultrasonographic maturation was assessed in 88.4% and 78.3% of AVF, respectively (kappa = 0.539). Non‐significant differences in clinical or ultrasonographic maturation were seen between exercise and control group (94.7% vs. 80.6%, P = 0.069; 81.6% vs. 74.2%, P = 0.459). A stepwise logistic regression was performed to control previously analyzed asymmetrically distributed confounding factors (AVF localization), revealing that the exercise group showed greater clinical, but not ultrasonographic, maturation (odds ratio [OR] 5.861, 95% confidence interval: 1.006–34.146 and OR 2.403, 0.66–8.754). A postoperative controlled exercise program after AVF creation seems to increase 1‐month clinical AVF maturation in distal accesses. Furthermore, exercise programs should be taken into account, especially in distal accesses.     

H2S Promoted Oxidative Dehydrogenation of Hydrocarbons in Molten Media

The H₂S promoted oxidative dehydrogenation of butane to butadiene can be efficiently carried out if a molten salt medium, e.g. LiCl/KCl, is used to dissipate the heat from the highly exothermic reaction. The reaction is catalyzed by the addition of soluble salts such at Tl₂O₃, BaCl₂ or MnCl₂. Optimization of reaction conditions by varying temperature, space velocity and quantity of promoter results in a 53% olefin yield (5% butenes, 48% butadiene) at 80% butane conversion. The system is also shown to be efficient for the dehydrogenation of ethane to ethylene, propane to propylene, butene to butadiene and ethylbenzene to styrene.     

SO2 promoted oxidative dehydrogenation of ethylbenzene

It has been demonstrated that SO₂ acts as an efficient dehydrogenation agent in the conversion of ethylbenzene to styrene in the presence of alkali and alkaline earth metal oxide doped alumina and titania catalysts. Development of these catalysts, which give styrene yields of greater than 80% per pass, is described in the paper. The catalysts allow the use of close to stoichiometric amounts of sulphur dioxide, are active in the presence of steam diluent and show low deactivation with time. The effect of varying process conditions such as temperature, reactant concentration and diluent amount is also described.