Spatial distribution and pollution evaluation in dry riverbeds affected by mine tailings.

The objective of this study was to evaluate the level of pollution, sources and potential risk of heavy metals (Zn, Cu, Mn, Cd, Cr, Ni, Fe and Pb) and arsenic (As) in four dry riverbeds affected by mine tailing, which drain into one of the biggest coastal lagoon of Europe (Mar Menor). El Beal, La Carrasquilla, Las Matildes and Ponce dry riverbeds sediments were sampled along its course (20, 18, 13, 19 samples were collected, respectively), and total/soluble metal(loid)s, water soluble ions, nitrogen, and organic/inorganic carbon contents were analyzed. Spatial distribution, principal component analysis (PCA), hierarchical cluster analysis (HCA), contamination factor (Cf), pollution load index (PLI) and potential ecological risk index (RI) were used to identify the possible sources of metal(loid)s and to assess the sediment pollution status. The results showed that the mean total concentrations of As, Cu, Cd, Mn, Zn and Pb exceeded the natural background levels of the study area, with the highest values located close to the mining areas. Correlation and cluster analysis identified that Cd and Zn were associated mainly with anthropogenic activities for all riverbeds, while Cr and Ni come from parent. PLI graded the four riverbeds as contaminated by heavy metals, while RI manifested that 100% of samples located in El Beal, La Carrasquilla and Las Matildes had a significantly high ecological risk. Therefore, this study suggests that mine wastes are the main source of metal(loids) contamination in the dry riverbeds, which results can be used to design actions and measures to reduce the environmental impact of metal(loid)s in the Mar Menor coastal lagoon.

Anatomy and Design of Musculocutaneous Flaps in Nasal Reconstruction. / Anatomía y diseño de colgajos musculocutáneos en reconstrucción nasal.

The nose is a common site for skin tumors. The main arteries that supply the nose extend through the subcutaneous tissue. Submuscular dissection facilitates the design of safe, reliable musculocutaneous flaps that adapt well to the morphology of nasal defects. The diversity of these flaps makes them the first choice for reconstructing defects in more complex regions, such as the inner canthus of the eye and the nasal ala. We describe the surgical design of the procerus, V-Y nasalis, and lateral wall nasalis musculocutaneous flaps used to repair defects following tumor excision. The descriptions are illustrated by photographs taken by the authors during procedures and in cadaveric dissections.

Activity and foraging behaviour of the hoverfly Eristalinus aeneus (Scopoli, 1763) in protected cultivation of mango (Mangifera indica L.).

The hoverfly Eristalinus aeneus is an important pollinator of crops and wild plants. However, there is a lack of detailed information about its foraging behaviour and its potential as a managed pollinator of mango. Given the growing economic importance of protected cultivation of mango, our aim is to study the flight activity and foraging behaviour of E. aeneus on this crop. Eristalinus aeneus displayed a bimodal daily activity, with peaks during mid-morning and mid-afternoon. The activity was maintained over a wide range of temperature (from 17.8 up to 37.4°C), light intensity (from 8.2 up to 57.4 klux) and relative humidity (from 19.0 up to 88.8%). The syrphids were active most of the time in this crop, and we observed five different types of activity: foraging (67%), resting (17%), flying (10%), grooming (4%) and walking (2%). This hoverfly visited hermaphrodite flowers more often than male flowers. On average, it visited 36.46 ± 13.92 flowers per 5 min, with a higher number of floral visits for nectar feeding. The duration of the visits to hermaphrodite and male flowers was similar but pollen-feeding visits lasted longer (6.44 s per flower) than nectar-feeding ones (5.51 s per flower). The highest number of visits to mango inflorescences was observed during the morning, but the longest visits occurred at midday. The implication of these results for the potential use of E. aeneus as a managed pollinator in protected cultivation of mango is discussed.

Microwave Spectroscopy Reveals the Quantum Geometric Tensor of Topological Josephson Matter.

Quantization effects due to topological invariants such as Chern numbers have become very relevant in many systems, yet key quantities such as the quantum geometric tensor providing local information about quantum states remain experimentally difficult to access. Recently, it has been shown that multiterminal Josephson junctions constitute an ideal platform to synthesize topological systems in a controlled manner. We theoretically study properties of Andreev states in topological Josephson matter and demonstrate that the quantum geometric tensor of Andreev states can be extracted by synthetically polarized microwaves. The oscillator strength of the absorption rates provides direct evidence of topological quantum properties of the Andreev states.

Acute-onset smell and taste disorders in the context of COVID-19: a pilot multicentre polymerase chain reaction based case-control study.

BACKGROUND AND PURPOSE: Specific respiratory tract infections, including COVID-19, may cause smell and/or taste disorders (STDs) with increased frequency. The aim was to determine whether new-onset STDs are more frequent amongst COVID-19 patients than influenza patients. METHOD: This was a case-control study including hospitalized patients of two tertiary care centres. Consecutive patients positive for COVID-19 polymerase chain reaction (cases) and patients positive for influenza polymerase chain reaction (historical control sample) were assessed during specific periods, employing a self-reported STD questionnaire. RESULTS: Seventy-nine cases and 40 controls were included. No significant differences were found in basal features between the two groups. New-onset STDs were significantly more frequent amongst cases (31, 39.2%) than in the control group (5, 12.5 %) [adjusted odds ratio 21.4 (2.77-165.4, P = 0.003)]. COVID-19 patients with new-onset STDs were significantly younger than COVID-19 patients without STDs (52.6 ± 17.2 vs. 67.4 ± 15.1, P < 0.001). Amongst COVID-19 patients who presented STDs, 22 (70.9%) recalled an acute onset and it was an initial manifestation in 11 (35.5%). Twenty-five (80.6%) presented smell disorders (mostly anosmia, 14, 45.2%) and 28 (90.3%) taste disorders (mostly ageusia, 14, 45.2%). Only four (12.9 %) reported concomitant nasal obstruction. The mean duration of STD was 7.5 ± 3.2 days and 12 patients (40%) manifested complete recovery after 7.4 ± 2.3 days of onset. CONCLUSION: New-onset STDs were significantly more frequent amongst COVID-19 patients than influenza patients; they usually had an acute onset and were commonly an initial manifestation. The use of STD assessment in anamnesis as a hint for COVID-19 and to support individuals' self-isolation in the current epidemic context is suggested.

Clinical and histological characterization of vesicular COVID-19 rashes: a prospective study in a tertiary care hospital.

COVID-19 is an infectious disease caused by severe acute respiratory coronavirus 2 (SARS-CoV-2). Vesicular skin rashes have been reported as associated with COVID-19, but there is little information about this cutaneous manifestation. We designed a prospective observational study of patients diagnosed with COVID-19 who had vesicular lesions. Clinical characterization of skin findings was conducted by dermatologists. When possible, histological analysis and detection of SARS-CoV-2 in the content of the vesicles was performed. In total, 24 patients were included. A disseminated pattern was found in 18 patients (75%), and a localized pattern was found in 6 (25%). Median duration of the skin rash was 10 days. Of the 24 patients, 19 (79.2%) developed the skin rash after the onset of COVID-19 symptoms. Histological examination in two patients was consistent with viral infection, SARS-CoV-2 was not detected in four patients. This single-centre study shows the clinical characteristics of vesicular skin rashes in patients with COVID-19.

Enhancing Near-Field Radiative Heat Transfer with Si-based Metasurfaces.

We demonstrate in this work that the use of metasurfaces provides a viable strategy to largely tune and enhance near-field radiative heat transfer between extended structures. In particular, using a rigorous coupled wave analysis, we predict that Si-based metasurfaces featuring two-dimensional periodic arrays of holes can exhibit a room-temperature near-field radiative heat conductance much larger than any unstructured material to date. We show that this enhancement, which takes place in a broad range of separations, relies on the possibility to largely tune the properties of the surface plasmon polaritons that dominate the radiative heat transfer in the near-field regime.

Theoretical study of carbon-based tips for scanning tunnelling microscopy.

Motivated by recent experiments, we present here a detailed theoretical analysis of the use of carbon-based conductive tips in scanning tunnelling microscopy. In particular, we employ ab initio methods based on density functional theory to explore a graphitic, an amorphous carbon and two diamond-like tips for imaging with a scanning tunnelling microscope (STM), and we compare them with standard metallic tips made of gold and tungsten. We investigate the performance of these tips in terms of the corrugation of the STM images acquired when scanning a single graphene sheet. Moreover, we analyse the impact of the tip-sample distance and show that it plays a fundamental role in the resolution and symmetry of the STM images. We also explore in depth how the adsorption of single atoms and molecules in the tip apexes modifies the STM images and demonstrate that, in general, it leads to an improved image resolution. The ensemble of our results provides strong evidence that carbon-based tips can significantly improve the resolution of STM images, as compared to more standard metallic tips, which may open a new line of research in scanning tunnelling microscopy.

Killer-cell immunoglobulin-like receptors and cytomegalovirus reactivation during late pregnancy.

Human cytomegalovirus (CMV) represents an important public health concern as it is associated with severe morbidity and mortality in transplant recipients, HIV-infected individuals and pregnant women given the risk of congenital infection. Congenital CMV is a leading cause of neurological sequelae, developmental delay and birth defects worldwide. Cytomegalovirus can be transmitted to the foetus following maternal infection or reactivation. NK cells expressing killer-cell immunoglobulin-like receptors (KIR) are part of the innate immune system and the first line of defence against viral incursions. Previous reports have shown that KIR genes are associated with CMV infections in the post-transplant setting. In this study, we set out to determine whether a protective effect of KIR genes over CMV infection is seen in Mexican pregnant women. Cytomegalovirus infection was assessed through nucleic acid testing in 200 pregnant women and 600 healthy blood donors comprising the Mexican mestizo reference population. Killer-cell immunoglobulin-like receptors and HLA-C genotypes were obtained from 200 pregnant women and 300 reference samples using a comprehensive PCR-SSP approach. We observed statistically lower carrier frequencies of cB03|tA01 gene-content haplotype, of cB03 haplotype motif, of the KIR2DL5 + 2DS3/2DS5 gene pair and of KIR2DL5 amongst CMV-positive pregnant women in comparison with those CMV negative. None of these were associated with CMV status in the reference population. Logistic regression analysis revealed that the most important factor determining CMV status during third-trimester pregnancies was the KIR2DL5 + 2DS3/2DS5 gene pair (OR 0.376 (95%CI 0.174, 0.811, P = 0.013). Our results indicate that CMV-protective KIR gene associations described in Caucasoid populations are also present in the genetically distinct Mexican mestizo population. Our results suggest that certain KIR gene combinations provide protection against CMV infections occurring during late-term pregnancies, a finding of utmost epidemiological importance given its implication with congenital CMV infections.

Transversal modulation ion mobility spectrometry (IMS) coupled with mass spectrometry (MS): exploring the IMS-IMS-MS possibilities of the instrument.

A prototype is introduced based on the transversal modulation ion mobility spectrometry (TMIMS) technique, which provides a continuous output of mobility-selected ions, greatly easing the synchronization between different analyzing stages. In the new architecture, two stages of filtration are used to drastically reduce the background produced by one stage alone. Two-stages TMIMS was coupled with two different atmospheric pressure interface mass spectrometers (MS). The new system enables IMS-IMS-MS analysis and other modes of operation: IMS prefiltration, IMS-IMS, and full transmission mode. It provides a resolving power R > 60 in IMS mode, and R > 40 in each stage of IMS-IMS mode. 2-Propanol vapors were introduced in one of the stages to enhance the mobility variations, and their effect was studied on a set of tetraalkylammonium ions. We found that concentrations as low as 1% (in partial pressure) produce mobility variations as high as 20%, which suggest that IMS-IMS separation using dried N2 (in one stage) and a dopant (in the other stage), could be a very powerful way to enhance the separation capacity of the IMS-IMS prefiltration approach.

Faraday effect in hybrid magneto-plasmonic photonic crystals.

We present a theoretical study of the Faraday effect in hybrid magneto-plasmonic crystals that consist of Au-Co-Au perforated membranes with a periodic array of sub-wavelength holes. We show that in these hybrid systems the interplay between the extraordinary optical transmission and the magneto-optical activity leads to a resonant enhancement of the Faraday rotation, as compared to purely ferromagnetic membranes. In particular, we determine the geometrical parameters for which this enhancement is optimized and show that the inclusion of a noble metal like Au dramatically increases the Faraday rotation over a broad bandwidth. Moreover, we show that the analysis of the Faraday rotation in these periodically perforated membranes provides a further insight into the origin of the extraordinary optical transmission.

Treatment with afobazole at delayed time points following ischemic stroke improves long-term functional and histological outcomes.

There is currently a significant lack of therapeutic options for acute ischemic stroke, and no drug has been approved for treating patients at delayed time points (≥6h post-stroke). Afobazole, an anxiolytic currently used clinically in Russia, has been shown to reduce neuronal and glial cell injury in vitro following ischemia. Experiments using the permanent middle cerebral artery occlusion (MCAO) rat model were carried out to determine if afobazole can reduce ischemic stroke damage in vivo and expand the therapeutic window for stroke treatment. Post-stroke (24h) application of afobazole (0.3-3mg/kg) significantly decreased infarct volume at 96h post-surgery, as determined by Fluoro-Jade and NeuN staining of brain sections. Moreover, afobazole helped preserve both the levels and normal histological distribution of myelin basic protein, indicating a reduction in white matter injury. A time-dependence study showed that either pre-treatment or treatment started 6 to 48h post-stroke with the drug yields improved outcomes at 96h. The decrease in infarct volume produced by afobazole was blocked by the application of either a σ-1 (BD 1063, 30mg/kg) or a σ-2 (SM-21, 1mg/kg) antagonist, indicating that both receptor subtypes are involved in the effects of afobazole. Treatment with afobazole starting at 24h post-stroke resulted in enhanced survival one month following surgery. Behavioral testing of animals 28-32days post-surgery using the elevated body swing and forelimb grip-strength tests revealed that treatment with afobazole starting 24h post-stroke significantly reduces behavioral deficits caused by ischemic stroke. The increase in survival and improved functional outcomes are accompanied by a reduction in infarct volume, as determined by thionin staining of brain sections. Taken together, our data support the use of afobazole as a post-stroke pharmacological agent to expand the current therapeutic window.

Scanning tunneling spectroscopy study of the proximity effect in a disordered two-dimensional metal.

The proximity effect between a superconductor and a highly diffusive two-dimensional metal is revealed in a scanning tunneling spectroscopy experiment. The in situ elaborated samples consist of superconducting single crystalline Pb islands interconnected by a nonsuperconducting atomically thin disordered Pb wetting layer. In the vicinity of each superconducting island the wetting layer acquires specific tunneling characteristics which reflect the interplay between the proximity-induced superconductivity and the inherent electron correlations of this ultimate diffusive two-dimensional metal. The observed spatial evolution of the tunneling spectra is accounted for theoretically by combining the Usadel equations with the theory of dynamical Coulomb blockade; the relevant length and energy scales are extracted and found in agreement with available experimental data.

Effects of pneumoperitoneum and body position on the morphology of the caudal cava vein analyzed by MRI and plastinated sections.

BACKGROUND: Pneumoperitoneum and patient positioning are essential factors during laparoscopic surgical procedures. They cause hemodynamic and anatomical changes in several abdominal organs among which the caudal cava vein (CCV) is involved. Hemodynamic changes in this vein (decreased venous return) have been described in the porcine model, but how the vein morphology and size is affected at different abdominal levels is unknown. We sought to assess the morphological and morphometrical changes in the CCV of the pig caused by pneumoperitoneum and the reverse Trendelenburg position by in vivo magnetic resonance imaging (MRI). METHODS: Six pigs were scanned via MRI under four situations: S1, control (no pneumoperitoneum); S2, control in the reverse Trendelenburg position; S3, pneumoperitoneum (14 mmHg); and S4, pneumoperitoneum in the reverse Trendelenburg position. MRI and plastinated body sections were used to evaluate the topography, morphology and cross-sectional area of the CCV. RESULTS: Two portions of the CCV were differentiated: a prehepatic portion (located between the vertebral levels L1-T15) with flat and irregular morphology, and a hepatic portion (between T14-T11) that was almost rounded. The reverse Trendelenburg position caused an increase in the lumen affecting mainly the prehepatic portion, while pneumoperitoneum caused a decrease in the total vascular lumen, exerting a greater effect on the hepatic portion. The combination of both situations resulted in a further decrease in the vascular area and global morphological changes. CONCLUSIONS: The pneumoperitoneum and reverse Trendelenburg position caused morphological and morphometrical changes in the prehepatic and hepatic portions of the CCV, which should assist in gaining a better understanding of the hemodynamic changes described in the literature.

Analysis of exosome release and its prognostic value in human colorectal cancer.

A significant proportion of extracellular nucleic acids in plasma circulate highly protected in tumor-specific exosomes, but it is unclear how the release of exosomes is modulated in carcinogenesis. We quantified by cytometry exosomes in plasma of 91 colorectal cancer patients to evaluate their potential as a tumor indicator and their repercussions on diagnosis and prognosis. We examined the involvement of TSAP6, a TP53-regulated gene involved in the regulation of vesicular secretion, in levels of circulating exosomes in plasma of colorectal patients and in HCT116 TP53-(wild-type and null) human colorectal cancer cell lines. The fraction of exosomes in cancer patients was statistically higher than in healthy controls (mean rank » 53.93 vs. 24.35). High levels of exosomes in plasma of patients correlated with high levels of carcino-embryonic antigen (P » 0.029) and with poorly differentiated tumors (P » 0.039) and tended to have shorter overall survival than patients with low levels (P » 0.056). Release of exosomes did not correlate with TSAP6 expression; and regulation of TSAP6 by TP53 was not shown either in tumor samples or in HCT116 cell lines. Although it was not suggested that the TP53/TSAP6 pathway regulates the release of exosomes into the plasma of colorectal cancer patients, the level of circulating exosomes may be used as a tumor indicator, because it correlates with poor prognosis parameters and shorter survival.

Usefulness of EUCAST rapid antibiotic susceptibility breakpoints and screening cut-off values directly from blood cultures for the inference of ß-lactam resistance mechanisms in Enterobacterales.

Background: Reducing the turnaround time for reporting antimicrobial susceptibility testing (AST) results is important for adjusting empirical treatments and may impact clinical outcomes of septic patients, particularly in settings with high antimicrobial resistance. Disc diffusion could be useful for inferring ß-lactam resistance mechanisms. Objectives: To evaluate the usefulness of EUCAST rapid AST (RAST) disc diffusion breakpoints for the screening of resistance mechanisms (sRAST) and interpretive reading of resistance phenotypes to infer ESBL and carbapenemases production in Enterobacterales. Methods: Blood cultures were artificially spiked with Enterobacterales clinical isolates with well-characterized ß-lactam resistance mechanisms (n = 93), WT phenotypes (n = 26) and ATCC strains (n = 8). AST was performed by disc diffusion directly from blood cultures and inhibition zones were manually measured at 4, 6 and 8 h. To infer the presence of resistance mechanisms, EUCAST RAST breakpoints and screening cut-off values (sRAST) combined with the double-disc synergy test (DDS) for ESBLs or aztreonam susceptibility for carbapenemases detection were used. Results: DDS together with sRAST detected all ESBL producers as early as at 4 h incubation. Cefotaxime was the antibiotic with the highest discriminatory power. The suspicion of carbapenemase production by sRAST at 8 h was possible in 73% of Klebsiella pneumoniae and in 100% of Escherichia coli carbapenemase-producing isolates. Phenotypic analysis improves the detection of some low hydrolytic carbapenemases (OXA-48 or KPC-3 mutants). Conclusions: Early detection of ß-lactam resistance mechanisms directly from positive blood cultures was possible using sRAST together with the interpretive reading of antibiotic resistance phenotypes. Some carbapenemase types such as OXA-48 might be difficult to infer. Screening-positive isolates should be confirmed using an alternative technique.

Transversal Modulation Ion Mobility Spectrometry (TM-IMS), a new mobility filter overcoming turbulence related limitations.

The analysis of ions according to their mobility is a technique that is attracting increasing interest. The new technology presented here, which we have termed Transversal Modulation Ion Mobility Spectrometry (TM-IMS), utilizes only electric fields, operates at atmospheric pressure, produces a continuous output of mobility selected ions (according to their true mobility and not to nonlinear effects), and has a very accessible inlet and outlet. These features would make it an ideal choice for tandem IMS-MS analysis in combination with most commercial Atmospheric Pressure Interface MS (API-MS) systems. We modeled and evaluated two different TM-IMS configurations (TM-IMS, and multistage TM-IMS), and we concluded that the most promising configuration would be a two-stage TM-IMS. We developed and tested a TM-IMS, and the measured resolving power is R = 55. The TM-IMS behaves similarly to the planar Differential Mobility Analyzer, but the TM-IMS utilizes only electric fields, and no fragile flow with high Reynolds numbers is required. We tested the robustness of the TM-IMS, which proves to be a very robust and reliable analyzer: the required voltage accuracy is 5 V in 10 kV, and the mechanical precision is 1 mm in 5 cm.

Generation of localized modes in an electrical lattice using subharmonic driving.

We show experimentally and numerically that an intrinsic localized mode (ILM) can be stably produced (and experimentally observed) via subharmonic, spatially homogeneous driving in the context of a nonlinear electrical lattice. The precise nonlinear spatial response of the system has been seen to depend on the relative location in frequency between the driver frequency, ω(d), and the bottom of the linear dispersion curve, ω(0). If ω(d)/2 lies just below ω(0), then a single ILM can be generated in a 32-node lattice, whereas, when ω(d)/2 lies within the dispersion band, a spatially extended waveform resembling a train of ILMs results. To our knowledge, and despite its apparently broad relevance, such an experimental observation of subharmonically driven ILMs has not been previously reported.

Interaction of organic contaminants with natural clay type geosorbents: potential use as geologic barrier in urban landfill.

The aim of this work is to characterize the capability of several clay materials as preservative of organic pollution for use as landfill barrier. Interaction of representative organic pollutants with different polarity and water solubility (atrazine, benzamide, methomyl, paraquat and toluene) with several clay materials coming from several locations of Spain were studied. Batch suspension method was used to study the pesticide adsorption onto the clay sorbents in solution conditions that simulate the composition of a young leachate in its aerobic acetogenic stage (pH=5 and I=0.15) The obtained data of the analytes sorption were modelized by several sorption isotherm models, and the best fitted data were got with a generalized Langmuir adsorption isotherm. The higher maxima adsorptions were observed for paraquat (50-62 mmol kg(-1)) and toluene (19-34 mmol kg(-1)) whereas more hydrophobic compounds present lower adsorption (0.7-2.5 mmol kg(-1)). Paraquat is the compound that presents the higher bonding coefficients. Therefore these clays could be used as components of the multibarriers in controlled urban landfill.