Barrier potential for laser written graphitic wires in diamond

Diamond substrates supporting an internal array of conductive graphitic wires inscribed by a femtosecond pulse laser, are useful for the detection of ionising radiation in a range of applications. Various parameters involved in the laser fabrication process were investigated in this paper to understand their impact on the electrical properties of the wires. The study revealed an effect, whereby the wires exhibit insulating behaviour until a barrier potential is overcome. When high enough voltages are applied, the wires display ohmic behaviour. The magnitude of the barrier potential, which in some cases exceeds 300 V, is shown to be strongly dependent on the laser fabrication parameters. Through process optimisation, the potential barrier may be minimised and effectively removed, coinciding with reduced values of the wire resistance

Module production of the one-arm AFP 3D pixel tracker

The ATLAS Forward Proton (AFP) detector is designed to identify events in which one or two protons emerge intact from the LHC collisions. AFP will consist of a tracking detector, to measure the momentum of the protons, and a time of flight system to reduce the background from multiple proton-proton interactions. Following an extensive qualification period, 3D silicon pixel sensors were selected for the AFP tracker. The sensors were produced at CNM (Barcelona) during 2014. The tracker module assembly and quality control was performed at IFAE during 2015. The assembly of the first AFP arm and the following installation in the LHC tunnel took place in February 2016. This paper reviews the fabrication process of the AFP tracker focusing on the pixel modules.Comment: PIXEL 2016 proceedings; Submitted to JINS

Application of multivariate analysis to investigate potential antioxidants in conventional and torrefacto roasted coffee

In the present work multivariate statistical techniques were applied to the coffee compounds and the overall antioxidant capacity of commercial conventional and torrefacto roasted coffees in order to investigate the main antioxidant compounds in coffee. Statistical analyses showed significant correlations between browned compounds, trigonelline, 5-caffeoylquinic acid and cafeic acid contents with the antioxidant activity measured by both DPPH- and redox potential methods. Trigonelline solutions showed an antioxidant capacity close to zero and should not be considered as a potential antioxidant compound. Principal Component Analysis (PCA) was applied to evidence the correlations between antioxidant capacity and coffee chemical compounds. Conventional and torrefacto roasted coffees were separated by PC1 (62.5% of the total variance) characterized by antioxidant capacity and chemical compounds highly correlated with antioxidant capacity. Furthermore, a descriptive chemical characterization of conventional and torrefacto ground roasted coffee has been carried out. Sixty-nine volatile compounds were identified and quantified. Their negative correlations with antioxidant capacity suggest a prooxidant capacity that should need further investigations

Structural Phase Transition and Superconductivity in 2H-BaGaGe with Buckled Honeycomb Layers

We report on the structural and superconducting properties of the intermetallic compound BaGaGe. We find that this material undergoes a structural second-order phase transition from the distorted AlB$_2$-type structure (1H, $a$ = 4.3254(2) \r{A}, $c$ = 5.1078(3) \r{A}, P6/mmm) into the CaIn$_2$-type structure (2H, $a$ = 4.3087(3) \r{A}, $c$ = 10.2117(6) \r{A}, P6$_3$/mmc) at a transition temperature of $T_{\rm S}$ = 253 K. We find that the structural phase-transition corresponds to a coherent buckling of the honeycomb layers, which we can interpret as a disorder-to-order transition of the atoms located within this layer. We show that the 2H-BaGaGe phase becomes superconducting at a critical temperature of $T_{\rm c}$ = 2.1 K. The bulk nature of the superconductivity in 2H-BaGaGe is confirmed by means of specific heat measurements, where we determine a value of $\Delta C$/$\gamma T_{\rm c}$ = 1.59, which is close to the expected BCS value in the weak coupling limit

A micellar formulation of quercetin prevents cisplatin nephrotoxicity

Producción CientíficaThe antioxidant flavonoid quercetin has been shown to prevent nephrotoxicity in animal models and in a clinical study and is thus a very promising prophylactic candidate under development. Quercetin solubility is very low, which handicaps clinical application. The aim of this work was to study, in rats, the bioavailability and nephroprotective efficacy of a micellar formulation of Pluronic F127-encapsulated quercetin (P-quercetin), with improved hydrosolubility. Intraperitoneal administration of P-quercetin leads to an increased plasma concentration and bioavailability of quercetin compared to the equimolar administration of natural quercetin. Moreover, P-quercetin retains overall nephroprotective properties, and even slightly improves some renal function parameters, when compared to natural quercetin. Specifically, P-quercetin reduced the increment in plasma creatinine (from 3.4 ± 0.5 to 1.2 ± 0.3 mg/dL) and urea (from 490.9 ± 43.8 to 184.1 ± 50.1 mg/dL) and the decrease in creatinine clearance (from 0.08 ± 0.02 to 0.58 ± 0.19 mL/min) induced by the nephrotoxic chemotherapeutic drug cisplatin, and it ameliorated histological evidence of tubular damage. This new formulation with enhanced kinetic and biopharmaceutical properties will allow for further exploration of quercetin as a candidate nephroprotector at lower dosages and by administration routes oriented towards its clinical use.Fundación de Universidades y Enseñanzas Superiores de Castilla y León (FUESCyL) y Banco de Santander - (grant: Ed. 2014– 2015 Desafío UNIV-EMP)Fundación General de la Universidad de Salamanca, Fondo Europeo de Desarrollo Regional (FEDER) y Junta de Castilla y León - (grant: Ed. 2015 Lanzadera TC)Junta de Castilla y León - (grant: VA225U14

Flavonoids: Important Biocompounds in Food

Flavonoids are secondary metabolites in plants that show some desirable characteristics. These compounds can be grouped in different classes on the basis of their basic structure. It has been reported that flavonoids are important for human health because of their antioxidant, antibacterial, antiviral, and anti‐inflammatory activities and because they act as free radical scavengers as they are potential reducing agents that protect from oxidative damage, which are conferred by the content of hydroxyl groups. In recent years, flavonoids have been investigated based on their ability to reduce the incidence of many diseases, to inhibit cell damage, to repair DNA process and to reduce oxidative stress. Besides, flavonoids have been demonstrated to have cardioprotective effects, have potential to improve coronary vasodilatation and prevent LDLs from oxidizing and also showed potential neuroprotective effects. Moreover, flavonoids have been used in the food industry due to their ability to preserve foods, to provide colour and flavour and to make dietary supplements, among other important industrial applications

Effect of ultra high temperature (UHT) treatment on coffee brew stability

In this work, the influence of an Ultra High Temperature (UHT) treatment on chemical and sensory composition of Arabica coffee brews for a longer shelf-life has been studied. A temperature of 120 degrees C for 2 s allows to obtain a microbiologically safe coffee brew, good valued from the sensory point of view. The behavior of the UHT vs non UHT treated coffee brew was followed throughout 120 days of storage at 4 degrees C. The UHT treatment keeps the typical acidity of the brews longer, delaying and softening the pH decrease and the development of sourness, which is one of the main causes for the rejection of stored coffee brews. The UHT treatment hardly affects the concentrations of caffeine and trigonelline, and of some phenolic compounds such as 5-caffeoylquinic (5-CQA), caffeic or ferulic acids. Sixteen key odorants and staling volatiles were analyzed by HS-GC-MS and lower changes were observed in the UHT treated coffee brew throughout storage. Higher DPPH center dot scavenging activity was observed in the UHT treated coffee brew from days 60 to 120. In conclusion, the application of an UHT treatment is proposed to extend the shelf-life (up to 60 days) of stored coffee brews

Polycyclic aromatic hydrocarbons in the dwarf galaxy IC 10

Infrared observations from the Spitzer Space Telescope archive are used to study the dust component of the interstellar medium in the IC~10 irregular galaxy. Dust distribution in the galaxy is compared to the distributions of H$\alpha$ and [SII] emission, neutral hydrogen and CO clouds, and ionizing radiation sources. The distribution of polycyclic aromatic hydrocarbons (PAH) in the galaxy is shown to be highly non-uniform with the mass fraction of these particles in the total dust mass reaching 4%. PAHs tend to avoid bright HII regions and correlate well with atomic and molecular gas. This pattern suggests that PAHs form in the dense interstellar gas. We propose that the significant decrease of the PAH abundance at low metallicity is observed not only globally (at the level of entire galaxies), but also locally (at least, at the level of individual HII regions). We compare the distribution of the PAH mass fraction to the distribution of high-velocity features, that we have detected earlier in wings of H$\alpha$ and SII lines, over the entire available galaxy area. No conclusive evidence for shock destruction of PAHs in the IC~10 galaxy could be found.Comment: Accepted for publication in Astronomy Report

Total dairy consumption in relation to overweight and obesity in children and adolescents: A systematic review and meta-analysis

A systematic review and meta-analysis of cross-sectional and prospective cohort studies was conducted to assess the associations between total dairy consumption and its different subtypes with the prevalence and incidence of overweight, obesity, and overweight/obesity in children and adolescents. A literature search was conducted in Medline through PUBMED and Cochrane Library databases until October 18, 2021. Articles reporting the risk estimates as odd ratios (OR), risk ratios (RR), or hazard ratios and their corresponding 95% confidence interval (CI) for the association between dairy product consumption and the risk of overweight and/or obesity were included. In the meta-analysis from cross-sectional studies, results showed an inverse association between total dairy consumption and obesity prevalence (OR (95% CI): 0.66 (0.48–0.91). No significant associations were found between milk or yogurt and obesity prevalence risk. Regarding prospective studies, total milk consumption was positively associated with overweight prevalence (OR (95% CI): 1.13 (1.01–1.26)) and incidence (RR (95%CI): 1.17 (1.01–1.35)) risk. Evidence from pooled analysis of cross-sectional studies suggested an inverse association between total dairy consumption and obesity. However, there is limited and no conclusive evidence to confirm an inverse relationship from pooled analysis of prospective studies in children and adolescents