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This article is oriented to the degradation of nickel in an ionic state at laboratory level from synthetic water made with nickel sulfate, using the electrocoagulation process with aluminum cathodes and modifying this process by the addition of the Fenton reagent, which results from the combination of hydrogen peroxide (H2O2) and ferrous sulfate (FeSO4) being this reagent a catalyst and oxo-coagulant agent, The efficiency of this reagent will be compared with the typical treatment with aluminum sulfate, which is a typical process based on ion exchange/coagulation at the same percentage concentrations as the Fenton reagent. For this purpose, the optimum conditions of the advanced electrocoagulation process were determined, which consisted of determining the concentrations of Fenton’s reagent at concentrations of 150 ppm, 300 ppm, and 450 ppm, in addition to the operating variables such as pH of 8 and 10, voltage of 17.5 V and 19 V and their reaction time, which were compared with aluminum sulfate at 300 ppm, 600 ppm, and 900 ppm. The results obtained with respect to the typical treatment were 0% nickel degradation. However, with the advanced oxidation treatment, an average reduction of 97.5% was found at the conditions of 19 V, pH 10, and Fenton 150 ppm in a time of 30 min.

Distribution amplitudes are functions of non-perturbative matrix elements describing the hadronization of quarks and gluons. Thanks to factorization theorems, they can be used to compute the scattering amplitude of high-energy processes. Recently, new ideas have allowed their computation using lattice QCD, which should provide us with a general, fully relativistic determination. We present the first lattice calculation of the ηc-meson distribution amplitude at leading twist. Starting from the relevant matrix element in discrete Euclidean space on a set of Nf = 2 CLS ensembles, we explain the method to connect to continuum Minkowski spacetime. After addressing several sources of systematic uncertainty, we compare to Dyson-Schwinger and non-relativistic QCD determinations of this quantity. We find significant deviations between the latter and our result even at small Ioffe times. [ABSTRACT FROM AUTHOR]

Human papillomavirus (HPV)-positive Head and Neck Squamous Cell Carcinomas (HNSCC) comprise a particular cancer entity traditionally associated with better clinical outcomes. Around 25% of HNSCC are HPV positive, HPV16 being the most prevalent type. Nevertheless, close to 30% of the HPV-positive patients have an unfavorable prognosis, revealing that this type of tumor exhibits great heterogeneity leading to different clinical behaviors. Efforts have been made to identify RNA molecules with prognostic value associated with the clinical outcome of patients with HPV-positive HNSCC, with the aim of identifying patients at high risk of metastasis, disease recurrence, and poor survival, who would require closer clinical follow-up and timely intervention. Moreover, the molecular identification of those HPV-positive HNSCC patients with good prognosis will allow the implementation of de-escalating therapeutic strategies, aiming to reduce side effects, resulting in a better quality of life. This review compiles a series of recent studies addressing different methodological and conceptual approaches aimed at searching for potential gene expression-based biomarkers associated with the prognosis of patients with HPV-positive HNSCC. [ABSTRACT FROM AUTHOR]

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The zero-age main sequence (ZAMS) is a critical phase for stellar angular momentum evolution, as stars transition from contraction-dominated spin-up to magnetic wind-dominated spin-down. We present the first robust observational constraints on rotation for FGK stars at ≈40 Myr. We have analyzed TESS light curves for 1410 members of five young open clusters with ages between 25 and 55 Myr: IC 2391, IC 2602, NGC 2451A, NGC 2547, and Collinder 135. In total, we measure 868 rotation periods, including 96 new, high-quality periods for stars around 1 M ⊙. This is an increase of ten times the existing literature sample at the ZAMS. We then use the τ 2 method to compare our data to models for stellar angular momentum evolution. Although the ages derived from these rotation models do not match isochronal ages, we show that these observations can clearly discriminate between different models for stellar wind torques. Finally, τ 2 fits indicate that magnetic braking and/or internal angular momentum transport significantly impact rotational evolution even on the pre-main sequence. [ABSTRACT FROM AUTHOR]

Abstract: Pathogenesis of diabetic foot infections include polineuropathy, macro and microvascular disease and neutrophil functional deficit. Endothelium dependent vasodilatation related to Nitric Oxide (NO) production is compromised in diabetics predisposed to foot ulceration. NO is also produced when neutrophils and macrophages are stimulated by cytokines or bacterial lipopolysaccarides through the inducible nitric oxide synthase (iNOS), exerting microbicide activity. Lipid peroxidation reflected by Malondialdehyde (MDA) production, is associated with diabetic microangiopathy development. To compare serum NO and MDA levels in patients with infected and non-infected diabetic foot, 27 type 2 diabetics, 38 to 65 years old were studied, and divided into three groups: 8 control subjects without foot affection (A), 10 with non-infected diabetic foot (B) and 9 with infected diabetic foot (C). NO was determined by diazotization assay and MDA by thiobarbituric acid assay. B and C showed lower NO levels (p = 7.636 x 10-5 and p = 0,006) compared with A group. NO was higher in the infected group than in the non-infected (p = 0,05), nevertheless, the obtained values do not coincide with the expected values considering the big amount of NO produced through iNOS, it suggests another defect of diabetic’s leukocyte. There were no significant differences in MDA between the groups, indicating absence of relevant oxidative stress. Resumen: La patogenia de las infecciones del pie diabético involucra la polineuropatía, la enfermedad macro y microvascular y el déficit funcional de los neutrófilos. La vasodilatación dependiente del endotelio, relacionada con el Óxido Nítrico (NO), está comprometida en diabéticos predispuestos a ulceración del pie. El NO, es producido también por neutrófilos y macrófagos estimulados por citoquinas o lipopolisacáridos bacterianos mediante la sintetasa de NO inducible (iNOS), ejerciendo actividad microbicida. La peroxidación lipídica reflejada por la producción de Malondialdehido (MDA), está implicada en el desarrollo de microangiopatía diabética. Para comparar los niveles séricos de NO y MDA en pacientes con pie diabético con y sin infección, se estudiaron 27 individuos diabéticos tipo 2 con edades entre 38 y 65 años divididos en 3 grupos: 8 controles sin afección de los pies (A), 10 con pie diabético sin infección (B) y 9 con pie diabético infectado (C). El NO fué determinado mediante ensayo de diazotización y el MDA mediante la reacción de Ácido Thiobarbitúrico. ByC mostraron niveles de NO menores (p = 7.636 x 10-5 y p = 0,006) que A. El NO fue mayor en el grupo infectado que en el grupo sin infección (p = 0,05), sin embargo los valores obtenidos no coinciden con lo esperado teniendo en cuenta las grandes cantidades de NO producido mediante la iNOS, sugiriendo un defecto más del leucocito del diabético. No hubo diferencia significativa en el MDA entre los grupos, indicando ausencia de stress oxidativo relevante.