The aim of this work was to develop an air diffusion mesoporous carbon electrode (ADE-MC) as cathode for the in-situ electrogeneration of hydrogen peroxide and its application on electro-Fenton (EF) ...and solar photo electro-Fenton (SPEF) processes. Three different mesoporous carbon materials were obtained by organic-organic self-assembly synthesis (soft-template route) by changing concentrations of resorcinol-formaldehyde polymer as carbon precursor and Pluronic F-127™ surfactant as matrix-forming agent. The materials were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), linear voltammetry (LV) and linear rotating disk electrode voltammetry (LV-RDE). MC materials showed pore diameter between 3.6 and 4.6 nm. The efficiency of ADE-MC was explored as a function of H2O2 produced at current densities (50, 100 and 150 mA cm−2). The highest production of H2O2 was 10.85 mmol L−1 by applying 150 mA cm−2. Finally, the ADE-MC were used for the mineralization of amoxicillin (50 mg L−1), allowing complete degradation and mineralization percentages of 55% and 85% with EF and SPEF processes, respectively. MC electrodes produce H2O2 in enough amounts that provide a viable option to degradation and mineralization of others organic pollutants in aqueous media by EF and SPEF processes.
There is evidence that maternal viral load of HCV during delivery influences the risk for Mother-to-child transmission (MTCT), but this does not explain all cases. We study the role of the ...immunogenetic profile (HLA, KIRs and KIR-ligand binding) of mothers and children in HCV-MTCT and in chronicity in the children.
79 HCV-RNA (+) mothers and their 98 children were included. 24 children were infected, becoming chronic in 8 cases and clearing in 16. HLA-class-I and II and KIRs were determined by Luminex.
MTCT study: The presence of HLA-C1-ligand in mothers and/or their children reduces the risk of transmission (mothers: Pc = 0.011, children: P = 0.033), whereas the presence of HLA-C2C2-ligand in mothers increases it (Pc = 0.011). In children KIR2DL3-HLA-C1 is a protector factor (Pc = 0.011). Chronicity in children study: Maternal DQA1*01 allele (Pc = 0.027), KIR2DS1 (Pc = 0.011) or KIR3DS1 (Pc = 0.011) favours chronicity in the child. The presence of the DQB1*03 allele (Pc = 0.027) and KIR2DS3 (P = 0.056) in the child and homozygosity for KIR3DL1/3DL1 (Pc = 0.011) and for the HLA-Bw4/Bw4 ligand (P = 0.027) is associated with viral clearance, whereas the presence of HLA-Bw6 ligand (P = 0.027), the binding of KIR3DS1-HLA-Bw4 (P = 0.037) and heterozygosity for KIR3DL1/3DS1 (Pc = 0.011) favour viral chronicity. Mother/child allele matching: In the joint HLA analysis, matching was greater between mothers and children with chronic infection vs those who had cleared the virus (67%±4.1 vs 57%±1.2, P = 0.003).
The HLA-C1 ligand in the mother is related to MTCT, while several genetic factors of the mother or child are involved in the chronification or clearance of infection in the child. Matching allelic data is considered to be an indicator of HCV chronicity in the child and can be used as a potential prognostic test. This implies that NK cells may play a previously undocumented role in protecting against MTCT and that both NK cell immunity and adaptive T-cell responses may influence viral clearance in infected children.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
An automated method to determine the band gap energy (Eg) of pure and mixed powder compounds using diffuse reflectance spectroscopy is presented. This method is based on a five-step algorithm that ...mimics the judgment made by an expert analyst in identifying the linear segments in Tauc plots and subsequent estimation of the Eg value. It is demonstrated that the method to estimate Eg by intersecting the straight-line fit of the Tauc segment with the photon energy axis is not appropriate for those samples containing more than one optical absorbing phase because systematic underestimation of the Eg value results. The automated method accounts for such cases by introducing a base line function. The robustness of the implemented algorithm was tested using three model systems, ZnO-Al2O3, ZnO-CoO and ZnO-CdO. The estimated Eg's using the automated method differ in less than 1% than those obtained by its manual counterpart.
► Antioxidant potential and antiproliferative effect of five monoterpenes was investigated. ► α-Terpineol presented good antioxidant activity in ORAC test. ► Limonene and α-terpineol presented ...equivalent antiproliferative profile in vitro. ► α-Terpineol had encouraging results against breast carcinoma and chronic myeloid leukemia. ► In vivo assays must be performed to confirm the anti-tumor potential of α-terpineol.
α-Terpineol is a relatively cheap and abundant aroma compound. It is widely used in food, cosmetics, and household products. Many of its monoterpene counterparts have been applied in antiproliferative assays, leading to promising results in the prevention or even treatment of cancers. However, despite its theoretic potential, no paper reports the evaluation of antiproliferative capacity of this alcohol. Thus, antioxidant potential of three monoterpenoids (carvone, perillyl alcohol, and α-terpineol) was measured using two methods: DPPH and ORAC. Also, the antiproliferative effect of these monoterpenoids against nine cancerous cell lines were performed and compared to limonene and doxorubicin. Results showed that all samples tested had very low antioxidant activity in the DPPH assay, but α-terpineol (2.72μmolTrolox equiv./μmol) could be compared to commercial antioxidants in the ORAC assay. The antiproliferative results obtained encourage future in vivo studies for α-terpineol, since this monoterpenoid presented cytostatic effect against six cell lines, especially for breast adenocarcinoma and chronic myeloid leukemia, in a range of 181–588μM.
Nowadays, India is the third-largest CO2 emitter and energy consumer in the world, and, it is soon expected to surpass China as the most populated country. Therefore, it is of great interest to ...analyse how India is developing its energy transition to a lower-carbon economy. This work analyses the evolution of the main driving forces of CO2 emissions in India during the period 1990–2016 through the use of an enlarged version of the Kaya identity, which establishes a link between CO2 emissions, types of energy sources (16), size of the economic sectors (3) and value of the Gross Domestic Product. India's CO2 emissions increased by 276% in the period under study, due to the rapid economic growth of India, which has been the dominating driving force contributing to the increase in CO2 emissions by 241%, while the energy intensity has been the main one reducing them by approximately −47%. So far, the use of coal has supported the rapid economic growth and the contribution of renewable energy, although significant, is still short compared to the total amount of energy employed. Remarkably, the estimated value of the emission intensity for 2020 supposes a 26% reduction concerning the value in 2005. According to this result, India is on the right pathway to fulfil its Nationally Determined Contribution but not to reduce its net CO2 emissions.
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•The per-capita income is the main contributor to CO2 emissions increase in India.•The energy intensity is the main contributor to CO2 emissions decrease in India.•The share of renewable energy in India has continuously dropped from 1990 to 2016.•India will reach its government target for 2020 regarding emission intensity.•India can fulfil its NDC without reducing its net CO2 emissions.
AIMS: To evaluate the impact of the amount and distribution of soil water on xylem anatomy and xylem hydraulics of current-year shoots, plant water status and stomatal conductance of mature ...‘Manzanilla’ olive trees. METHODS: Measurements of water potential, stomatal conductance, hydraulic conductivity, vulnerability to embolism, vessel diameter distribution and vessel density were made in trees under full irrigation with non-limiting soil water conditions, localized irrigation, and rain-fed conditions. RESULTS: All trees showed lower stomatal conductance values in the afternoon than in the morning. The irrigated trees showed water potential values around −1.4 and −1.6 MPa whereas the rain-fed trees reached lower values. All trees showed similar specific hydraulic conductivity (K ₛ) and loss of conductivity values during the morning. In the afternoon, K ₛ of rain-fed trees tended to be lower than of irrigated trees. No differences in vulnerability to embolism, vessel-diameter distribution and vessel density were observed between treatments. CONCLUSIONS: A tight control of stomatal conductance was observed in olive which allowed irrigated trees to avoid critical water potential values and keep them in a safe range to avoid embolism. The applied water treatments did not influence the xylem anatomy and vulnerability to embolism of current-year shoots of mature olive trees.
Abstract
Eridanus II (Eri II) is an ultrafaint dwarf (UFD) galaxy (
M
V
= −7.1) located at a distance close to the Milky Way virial radius. Early shallow color–magnitude diagrams (CMDs) indicated ...that it possibly hosted an intermediate-age or even young stellar population, which is unusual for a galaxy of this mass. In this paper, we present new Hubble Space Telescope/Advanced Camera for Surveys CMDs reaching the oldest main-sequence turnoff with excellent photometric precision and derive a precise star formation history (SFH) for this galaxy through CMD fitting. This SFH shows that the bulk of the stellar mass in Eri II formed in an extremely short star formation burst at the earliest possible time. The derived star formation rate profile has a width at half maximum of 500 Myr and reaches a value compatible with null star formation 13 Gyr ago. However, tests with mock stellar populations and with the CMD of the globular cluster M92 indicate that the star formation period could be shorter than 100 Myr. From the quantitative determination of the amount of mass turned into stars in this early star formation burst ( ∼2 × 10
5
M
⊙
) we infer the number of supernova (SN) events and the corresponding energy injected into the interstellar medium. For reasonable estimates of the Eri II virial mass and values of the coupling efficiency of the SN energy, we conclude that Eri II could be quenched by SN feedback alone, thus casting doubts on the need to invoke cosmic reionization as the preferred explanation for the early quenching of old UFD galaxies.
In this study, UiO-67 (Zr)/g-C3N4 composites (U67N) were synthesized at wt.% ratios of 05:95, 15:85, and 30:70 using the solvothermal method at 80 °C for 24 h followed by calcination at 350 °C. The ...composites were characterized using UV–Vis diffuse reflectance spectroscopy, Fourier-transform infrared spectroscopy, photoluminescence spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscopy–energy-dispersive X-ray spectroscopy, transmission electron microscopy, and nitrogen physisorption analysis. In addition, thermal stability analysis of UiO-67 was conducted using thermogravimetric analysis.
The photocatalytic performance of the composites was assessed during the degradation and mineralization of a mixture of methylparaben (MeP) and propylparaben (PrP) under simulated sunlight. The adsorption process of U67N 15:85 was characterized through kinetic studies and adsorption capacity experiments, which were modeled using pseudo-first-order and pseudo-second-order kinetics and Langmuir and Freundlich isotherms, respectively.
The influence of pH levels 3, 5, and 7 on the photocatalytic degradation of the mixture was investigated, revealing enhanced degradation and mineralization at pH 3. The U67N composite exhibited dual capability in removing contaminants through adsorption and photocatalytic processes. Among the prepared composites, U67N 15:85 demonstrated the highest photocatalytic activity, achieving removal efficiencies of 96.8% for MeP, 92.5% for PrP, and 45.7% for total organic carbon in 300 kJ/m2 accumulated energy (3 h of reaction time). The detoxification of the effluent was confirmed through acute toxicity evaluation using the Vibrio fischeri method.
The oxidation mechanism of the heterojunction formed between UiO-67 (Zr) and g-C3N4 was proposed based on PL analysis, photoelectrochemistry studies (including photocurrent response, Nyquist, and Mott–Schottky analyses), and scavenger assays.
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•UiO-67(Zr)/g-C3N4 showed dual capacity to remove parabens by adsorption and photocatalysis decreasing effluent toxicity.•U67N 15:85 reached the highest photocatalytic response in the degradation and mineralization of the MeP and PrP at pH 3.•Coupling UiO-67(Zr) into g-C3N4 improved activity by delaying recombination and promoting charge separation and migration.•The proposed band scheme suggests that O2•- radicals are primarily involved in parabens oxidation.
•A review on acaricide activity against ticks of plant products and secondary compounds was done.•Mortalities (5–100%) against the Rhipicephalus, Amblyomma, Dermacentor, Hyalomma and Argas genera ...were reported.•The families Lamiaceae, Fabaceae, Asteraceae, Piperaceae, Verbenaceae, and Poaceae are evaluated mainly.•Thymol, carvacrol, 1,8-cineol, n-hexanal, nicotine and sulfides are responsible for the acaricidal activity.•Plant metabolites could be used as an alternative control against susceptible or resistant ticks to commercial acaricides.
The present review documents the results of studies evaluating the acaricidal activity of different plant products and secondary metabolites against ticks that are resistant and susceptible to conventional acaricides. Studies published from 1998 to 2016 were included. The acaricidal activity of plant extracts, essential oils and secondary compounds from plants have been evaluated using bioassays with ticks in the larval and adult stages. There is variable effectiveness according to the species of plant and the concentrations used, with observed mortalities ranging from 5 to 100% against the Rhipicephalus (Boophilus), Amblyomma, Dermacentor, Hyalomma, and Argas genera. A number of plants have been reported to cause high mortalities and/or affect the reproductive capacity of ticks in the adult phase. In the majority of these trials, the main species of plants evaluated correspond to the families Lamiaceae, Fabaceae, Asteraceae, Piperaceae, Verbenaceae, and Poaceae. Different secondary metabolites such as thymol, carvacrol, 1,8-cineol and n-hexanal, have been found to be primarily responsible for the acaricidal activity of different essential oils against different species of ticks, while nicotine, dibenzyldisulfide and dibenzyltrisulfide have been evaluated for plant extracts. Only thymol, carvacrol and 1,8-cineol have been evaluated for acaricidal activity under in vivo conditions. The information in the present review allows the conclusion that the secondary metabolites contained in plant products could be used as an alternative for the control of ticks that are susceptible or resistant to commercial acaricides.
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