The total PAH associated to the airborne particulate matter (PM10) was apportioned by one receptor model based on positive matrix factorization (PMF) in an urban environment (Zaragoza city, Spain) ...during February 2010–January 2011. Four sources associated with coal combustion, gasoline, vehicular and stationary emissions were identified, allowing a good modelling of the total PAH (R2 = 0.99). A seasonal behaviour of the four factors was obtained with higher concentrations in the cold season. The NE direction was one of the predominant directions showing the negative impact of industrial parks, a paper factory and a highway located in that direction. Samples were classified according to hierarchical cluster analysis obtaining that, episodes with the most negative impact on human health (the highest lifetime cancer risk concentrations), were produced by a higher contribution of stationary and vehicular emissions in winter season favoured by high relative humidity, low temperature and low wind speed.
► PMF receptor model apportioned four sources associated to the total PAH in Zaragoza. ► The sources were: vehicular, coal combustion, gasoline and stationary emissions. ► Samples were additionally classified according to hierarchical cluster analysis. ► The stationary and vehicular emissions factors showed higher risk for human health. ► Low temperature, wind speed and high relative humidity favoured this negative impact.
Episodes with the most negative impact on human health regarding PAH were produced by a higher contribution of stationary and vehicular emissions in winter season.
The He
I
λ
10833 Å triplet is a powerful tool for characterising the upper atmosphere of exoplanets and tracing possible mass loss. Here, we analysed one transit of GJ 1214 b observed with the ...CARMENES high-resolution spectrograph to study its atmosphere via transmission spectroscopy around the He
I
triplet. Although previous studies using lower resolution instruments have reported non-detections of He
I
in the atmosphere of GJ 1214 b, we report here the first potential detection. We reconcile the conflicting results arguing that previous transit observations did not present good opportunities for the detection of He
I
, due to telluric H
2
O absorption and OH emission contamination. We simulated those earlier observations, and show evidence that the planetary signal was contaminated. From our single non-telluric-contaminated transit, we determined an excess absorption of 2.10
−0.50
+0.45
% (4.6
σ
) with a full width at half maximum (FWHM) of 1.30
−0.25
+0.30
Å. The detection of He
I
is statistically significant at the 4.6
σ
level, but repeatability of the detection could not be confirmed due to the availability of only one transit. By applying a hydrodynamical model and assuming an H/He composition of 98/2, we found that GJ 1214 b would undergo hydrodynamic escape in the photon-limited regime, losing its primary atmosphere with a mass-loss rate of (1.5–18) × 10
10
g s
−1
and an outflow temperature in the range of 2900–4400 K. Further high-resolution follow-up observations of GJ 1214 b are needed to confirm and fully characterise the detection of an extended atmosphere surrounding GJ 1214 b. If confirmed, this would be strong evidence that this planet has a primordial atmosphere accreted from the original planetary nebula. Despite previous intensive observations from space- and ground-based observatories, our He
I
excess absorption is the first tentative detection of a chemical species in the atmosphere of this benchmark sub-Neptune planet.
ABSTRACT
We study the star formation rate (SFR), stellar mass (M⋆), and the gas metallicity (Z) for 4636 galaxy pairs using the Galaxy And Mass Assembly (GAMA) survey. Our galaxy pairs lie in a ...redshift range of 0 < z < 0.35, mass range of 7.5 < log(M⋆/M⊙) < 11.5 and ΔV < 1000 km s−1. We explore variations in SFR and Z from three point of views: multiplicity, pair separation, and dynamics. We define multiplicity as the number of galaxies paired with a single galaxy, and analyzed for the first time variations in SFR and Z for both, single pairs and pairs with higher multiplicity. For the latter, we find SFR enhancements from 0.025–0.15 dex, that would shift the M–SFR relation of single pairs by 27${{\ \rm per\ cent}}$ to higher SFRs. The effect of Z, on the other hand, is of only 4${{\ \rm per\ cent}}$. We analyse the most and least massive galaxy of major/minor pairs as a function of the pair separation. We define major pairs those with mass ratios of 0.5 < M1/M2 < 2, while pairs with more discrepant mass ratios are classified as minor pairs. We find SFR enhancements of up to two and four times with respect to their control sample, for major and minor pairs. For the case of Z, we find decrements of up to 0.08 dex for the closest pairs. When we focus on dynamics, Z enhancements are found for minor pairs with high-velocity dispersion $(\sigma _p \gt 250 \,\, \mathrm{km\, s ^{-1}})$ and high multiplicity.
Achieving the stable osteointegration of prosthetic implants is one of the great challenges of modern orthopedic surgery. The fixation of ceramic acetabular cups of hip joint prostheses is usually ...achieved using a metal shell provided with screws or pegs that penetrate into the host pelvic bone. The deposition of bioactive coatings on the implant surface to be put in contact with bone could be a valuable strategy to promote a more "physiological" osteointegration. In this work, bioactive glass porous coatings were manufactured on the top of alumina/zirconia composite implants by two different methods, i.e., sponge replication and laser cladding. The coated samples underwent immersion studies in Kokubo's simulated body fluid (SBF) to assess in vitro bioactivity and were found to exhibit an excellent hydroxyapatite-forming ability, which is key to allow bonding to bone. Biological tests using mesenchymal stem and osteoblast-like cells revealed the good biocompatibility of both types of materials. Furthermore, a higher level of mineralization was induced by the sponge-replicated coatings at 10 days. Overall, these results are highly promising and encourage further research on these materials.
This work describes the development of a paper-based platform for highly sensitive detection of diclofenac. The quantification of this anti-inflammatory drug is of importance in clinical (e.g. ...quality and therapeutic control) and environmental (e.g. emerging contaminant determination) areas. The easy-to-handle platform here described consists of a carbon-ink paper-based working electrode and two metallic wires, provided by a gold-plated standard connector, as reference and counter electrodes. The porous paper matrix enables the preconcentration of the sample, decoupling sample and detection solutions. Thus, relatively large sample volumes can be used, which significantly improves the sensitivity of the method. A wide dynamic range of four orders of magnitude, between 0.10 and 100 μM, was obtained for diclofenac determination. Due to the predominance of adsorption at the lowest concentrations, there were two linear concentration ranges: one comprised between 0.10 and 5.0 μM (with a slope of 0.85 μA μM−1) and the other between 5.0 and 100 μM (with a slope of 0.48 μA μM−1). A limit of detection of 70 nM was achieved with this simple device that provided accurate results with an RSD of ca. 5%. The platform was applied for diclofenac quantification in spiked tap water samples. The versatility of this design enabled the fabrication of a multiplexed platform containing eight electrochemical cells that work independently. The low cost, small size and simplicity of the device allow on-site analysis, which is very useful for environmental monitoring.
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•Ultrasensitive paper-based electrochemical determination of an emerging contaminant.•Low-cost, disposable and multiplex electroanalytical device for the drug diclofenac.•A 60-fold sensitivity increase by preconcentration on a paper-based platform.•An 800-fold lower limit of detection preconcentrating DCF on paper working electrodes.•The paper-based platform provide wide concentration range (0.1-100 µM) and high precision.
Like China, Mexico has a traditional system of medicine dating back almost 5000 years that incorporates the healing practices of pre-Columbian civilizations, including the Maya and Aztec. Mexican ...Traditional Medicine (MTM) women depend on MTM practices and herbal medicines for their primary healthcare needs as limited access and high costs of Western medicine is a significant problem. The aims of this work were to determine the medicinal plants more commonly used in MTM for women's reproductive health issues and assess the clinical data supporting their use. Data from multiple sources was compiled and information on plants commonly used by women in Mexico MTM for the treatment of fertility and menstruation issues, pregnancy, and menopause was analyzed. Analysis of the data show that 185 species of plants representing > 60 families were used for a wide range of reproductive health issues. Some of these plants have been used in MTM for fertility regulation in women of which 35 species were used as emmenagogues and abortifacients. Approximate 40 species were used for the symptoms of premenstrual syndrome, heavy menstrual bleeding, and dysmenorrhea. In terms of pregnancy, 35 species were used for postpartum care and to facilitate breastfeeding, 16 species were used as oxytocic agents to induce labor and speed birth, and six plant species were used to prevent miscarriage. Fourteen plant species were reported to treat infertility or promote fertility, and seven species were used to treat uterine prolapse. Three plants species were reported to treat menopause and two plants were used for osteoporosis. Analysis of the clinical data for commonly used medicinal plants showed some clinical support for the use of these plants in MTM. In Mexico, women use medicinal plants for almost every aspect of reproductive health. While some plants have clinical data, most medicinal plants used in MTM have no safety or efficacy data available and could serve as the basis of future investigations.
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•Heterogeneity of composting process hinds the establishment of bioindicators.•Biodiversity and respirometric index affect phytostimulant power of compost.•Phenolic content and ...nitrification index could impact compost biodiversity.•Compost biodiversity is greater the lower the activity of xylanase.•Different raw materials evolve similar products by different bioestrategies.
Currently, the metagenomic study of the composting process has gained great importance since it has allowed the identification of the existence of microorganisms that, until now, had not been isolated during the process by traditional techniques. However, it is still complex to determine which bioindicators could reveal the degree of maturity and stability of a particular compost. Thereby, the main objective of this work was to demonstrate the possible correlation between traditional parameters of maturity and stability of compost, with other indicators of biodiversity in products highly heterogeneous from composting processes on an industrial scale.
The results demonstrated the enormous influence of the raw materials in characterizing the products obtained. Even so, important relationships were established between the Chao1 and Shannon indexes, and certain parameters related to the maturity, stability and toxicity of the samples, such as nitrification index, humification rate, phenolic content, germination index or oxygen consumption.
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•Metallomicelles of Ru(II) showed cytotoxic activity and selectivity by some cancer cell lines.•Confocal fluorescence microscopy demonstrated the interaction between micelles and ...DNA.•Metallomicelles of Ru(II) showed a good internalization into cancer and normal cells at low surfactant concentrations.•DNA acted as a catalyst in the structural change from spherical to elongated micelles.
The use of nanovectors in several medicinal treatments has reached a great importance in the last decade. Some drugs need to be protected to increase their lifetimes in the blood flow, to avoid degradation, to be delivered into target cells or to decrease their side effects. The goal of this work was to design and prepare nanovectors formed by novel surfactants derived from the Ru(bpy)32+ complex. These amphiphilic molecules are assembled to form metallomicelles which can act as pharmaceutical agents and, at the same time, as nanovectors for several drugs. TEM images showed a structural transition from spherical to elongated micelles when the surfactant concentration increased. Fluorescence microscopy confirmed the internalization of these metallomicelles into diverse cell lines and cytotoxicity assays demonstrated specificity for some human cancer cells. The encapsulation of various antibiotics was carried out as well as a thorough study about the DNA condensation by the metallomicelles. To the best of our knowledge, applications of these metallomicelles have not been shown in the literature yet.
GJ 3470b is a warm Neptune transiting an M-dwarf star at the edge of the evaporation desert. It offers the possibility of investigating how low-mass, close-in exoplanets evolve under the irradiation ...from their host stars. We observed three transits of GJ 3470b in the Lyman-α line with the Hubble Space Telescope (HST) as part of the Panchromatic Comparative Exoplanet Treasury (PanCET) program. Absorption signatures are detected with similar properties in all three independent epochs, with absorption depths of 35 ± 7% in the blue wing of the line, and 23 ± 5% in the red wing. The repeatability of these signatures, their phasing with the planet transit, and the radial velocity of the absorbing gas allow us to conclude that there is an extended upper atmosphere of neutral hydrogen around GJ 3470b. We determine from our observations the stellar radiation pressure and XUV irradiation from GJ 3470 and use them to perform numerical simulations of the upper atmosphere of GJ 3470b with the EVaporating Exoplanets (EVE) code. The unusual redshifted signature can be explained by the damping wings of dense layers of neutral hydrogen that extend beyond the Roche lobe and are elongated in the direction of the planet motion. This structure could correspond to a shocked layer of planetary material formed by the collision of the expanding thermosphere with the wind of the star. The blueshifted signature is well explained by neutral hydrogen atoms escaping at rates of about 1010 g s−1 that are blown away from the star by its strong radiation pressure and are quickly photoionized, resulting in a smaller exosphere than that of the warm Neptune GJ 436b. The stronger escape from GJ 3470b, however, may have led to the loss of about 4–35% of its current mass over its ~2 Gyr lifetime.
This paper describes the development of simple, sustainable, and low-cost strategies for signal enhancement on paper-based carbon platforms through gold nanoparticles electrogenerated from small ...volumes of tetrachloroauric (III) acid solutions. Carbon ink is deposited on a hydrophilic working area of the paper delimited with hydrophobic wax. This maskless procedure is fast and cuts down ink waste. The connection of this working electrode to the potentiostat is ensured with the use of screen-printed electrodes (SPEs). Close contact of the whole area of both carbon electrodes improves the precision of the nanostructuration. Resulting gold-modified paper-based carbon working electrodes (AuNPs-PCWEs) were characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), and electron dispersion X-ray spectrometry (SEM/EDX). This methodology was applied for the first time to the inorganic arsenic determination in commercial white wines by chronoamperometric stripping of the electrodeposited As(0). In an optimized system, As(III) was reduced and deposited as As(0) on the nanostructured surface by applying a potential of −0.3 V during 180 s. Then, anodic stripping chronoamperometry was performed at +0.4 V. The analytical signal was the current recorded at 30 s. On the other hand, As(V) was chemically reduced to As(III) with 0.2 M KI, and total determination of arsenic could be carried out. As(V) was determined as the difference between total As and As(III). Then, this fast, simple and low-cost method can be employed for speciation purposes. Limits of detection for As(III) and total arsenic (in the presence of KI) are 2.2 μg L–1 and 2.4 μg L–1, respectively, and indicate that this method is suitable for regulated quality control.
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