Coal pit lakes in abandoned mining areas in León (NW Spain): characteristics and geoecological significance

1-14 pMining activity introduces severe changes in landscapes and, subsequently, in land uses. One of the most singular changes is the existence of pit lakes, which occur in active and, more frequently, abandoned mines. Pit lakes are produced by water table interception when open-pit mines deepen. Their characteristics are highly variable, depending on the type of mine, the environment or the climate. In León province there is a long tradition of coal mining that dates back to the nineteenth century, and hundreds of open pits from the 1970s to 2018 have been opened, producing permanent landscape changes. This work analyses the main parameters, including morphological measurements, depth and pH values obtained from aerial photos and field work, of 76 coal pit lakes more than 30 m in length. The vast majority of these pit lakes were unknown until now and were not included in inventories or maps. The data obtained provide baseline knowledge that will allow, in the future, potential uses (storage of water for various uses, recreational use, wildlife habitat, and geological heritage sites) for these pit lakes and establish their importance as a new geoecological environment.S

One-year study of airborne sugar compounds: cross-interpretation with other chemical species and meteorological conditions

The daily evolution of seventeen sugar compounds (seven saccharides, seven alcohol-saccharides and three anhydrosaccharides) in atmospheric aerosol samples collected between 9 March 2016 and 14 March 2017 was studied in León (Spain). The main links between the concentration of sugar compounds and various chemical species, pollen, fungal spores and meteorological conditions were investigated. The results showed that, in spring, when high levels of metabolic activity of the plants occur and temperatures increase, glucose, sucrose, 2-methyl-erithritol, mannitol, arabitol and inositol, are significantly correlated with airborne pollen concentrations. Between spring and autumn, Alternaria air concentrations are significantly correlated with temperatures, arabitol and sorbitol + adonitol concentrations. Furthermore, during rainy days, Alternaria is also correlated with mannitol. In autumn, lower temperatures cause an increase in the concentrations of levoglucosan, mannosan and galactosan, probably due to the increased use of domestic heating devices. These anhydrosugars and arabinose, fructose and glucose, are significantly correlated with K, NO3−, EC, OC, Cu, Zn, Se, Pb, V and Ni, while mannosan also correlates with As, showing that these anhydrosaccharides can be emitted from different anthropogenic sources. Precipitation causes an increase in glucose and sucrose concentrations, due to the break of pollen particles that produce hundreds of fine size particles. Besides, precipitation causes an increase in arabitol concentrations, due to the release and growth of fungi.publishe

The field high-amplitude SX Phe variable BL Cam: results from a multisite photometric campaign. II. Evidence of a binary - possibly triple - system

Short-period high-amplitude pulsating stars of Population I ($\delta$ Sct stars) and II (SX Phe variables) exist in the lower part of the classical (Cepheid) instability strip. Most of them have very simple pulsational behaviours, only one or two radial modes being excited. Nevertheless, BL Cam is a unique object among them, being an extreme metal-deficient field high-amplitude SX Phe variable with a large number of frequencies. Based on a frequency analysis, a pulsational interpretation was previously given. aims heading (mandatory) We attempt to interpret the long-term behaviour of the residuals that were not taken into account in the previous Observed-Calculated (O-C) short-term analyses. methods heading (mandatory) An investigation of the O-C times has been carried out, using a data set based on the previous published times of light maxima, largely enriched by those obtained during an intensive multisite photometric campaign of BL Cam lasting several months. results heading (mandatory) In addition to a positive (161 $\pm$ 3) x 10$^{-9}$ yr$^{-1}$ secular relative increase in the main pulsation period of BL Cam, we detected in the O-C data short- (144.2 d) and long-term ($\sim$ 3400 d) variations, both incompatible with a scenario of stellar evolution. conclusions heading (mandatory) Interpreted as a light travel-time effect, the short-term O-C variation is indicative of a massive stellar component (0.46 to 1 M_{\sun}) with a short period orbit (144.2 d), within a distance of 0.7 AU from the primary. More observations are needed to confirm the long-term O-C variations: if they were also to be caused by a light travel-time effect, they could be interpreted in terms of a third component, in this case probably a brown dwarf star ($\geq$ 0.03 \ M_{\sun}), orbiting in $\sim$ 3400 d at a distance of 4.5 AU from the primary.Comment: 7 pages, 5 figures, accepted for publication in A&

Case report: Challenges and implications of conduction system pacing in pediatrics: Case series

Cardiac electrical stimulation in children usually is needed in the setting of complete congenital atrioventricular block, atrioventricular block after heart surgery, and bradycardia associated with some specific channelopathies. In cases of atrioventricular block, the high percentage of ventricular stimulation raises concern on the deleterious effects of chronic stimulation of the right ventricle. In recent years, physiologic stimulation has developed as a valid approach for adult patients and a great interest has risen in offering conduction system pacing also to the pediatric population. We present three pediatric cases of stimulation of the conduction system (His bundle or left bundle branch), in order to show the intrinsic particularities and challenges implied in these new techniques

Chitosan/Poly(Dllactide-Co-Glycolide) Scaffolds for Tis- sue Engineering

Abstract Chitosan/poly(DL-lactide-co-glycolide) (Ch/DL PLG) composite scaffolds were fabricated by freeze-drying lyophilization, and were evaluated and compared for use as a bone regeneration scaffold through measurements of the compression mechanical properties of the porous scaffolds. Also, In vitro cell culture of Sprague-Dawley rat's osteoblasts were used to evaluate the phenotype expression of cells in the scaffolds, characterizing the cellular adhesion, proliferation and alkaline phosphatase activity. The gene expression of osteocalcin, sialoprotein, alkaline phosphatase, Type I collagen and TGFb1 were confirmed in the samples; moreover, it was confirmed, the mineralization by IR spectra and EDS analysis. Our results thus show that Ch/DL PLG scaffolds are suitable for biological applications

Functional electrical stimulation therapy controlled by a P300-based brain–computer interface, as a therapeutic alternative for upper limb motor function recovery in chronic post-stroke patients. A non-randomized pilot study

IntroductionUp to 80% of post-stroke patients present upper-limb motor impairment (ULMI), causing functional limitations in daily activities and loss of independence. UMLI is seldom fully recovered after stroke when using conventional therapeutic approaches. Functional Electrical Stimulation Therapy (FEST) controlled by Brain–Computer Interface (BCI) is an alternative that may induce neuroplastic changes, even in chronic post-stroke patients. The purpose of this work was to evaluate the effects of a P300-based BCI-controlled FEST intervention, for ULMI recovery of chronic post-stroke patients.MethodsA non-randomized pilot study was conducted, including 14 patients divided into 2 groups: BCI-FEST, and Conventional Therapy. Assessments of Upper limb functionality with Action Research Arm Test (ARAT), performance impairment with Fugl–Meyer assessment (FMA), Functional Independence Measure (FIM) and spasticity through Modified Ashworth Scale (MAS) were performed at baseline and after carrying out 20 therapy sessions, and the obtained scores compared using Chi square and Mann–Whitney U statistical tests ( = 0.05).ResultsAfter training, we found statistically significant differences between groups for FMA (p = 0.012), ARAT (p < 0.001), and FIM (p = 0.025) scales.DiscussionIt has been shown that FEST controlled by a P300-based BCI, may be more effective than conventional therapy to improve ULMI after stroke, regardless of chronicity.ConclusionThe results of the proposed BCI-FEST intervention are promising, even for the most chronic post-stroke patients often relegated from novel interventions, whose expected recovery with conventional therapy is very low. It is necessary to carry out a randomized controlled trial in the future with a larger sample of patients

An additive manufactured CubeSat mirror incorporating a novel circular lattice

Additive Manufacturing (AM; 3D printing) for mirror fabrication allows for intricate designs that can combine lightweight structures and integrated mounting. Conventional lightweight structures utilise cubic or prismatic unit cells, which do not provide uniform support at the edge of curved mirrors. We present a new circular lattice based upon cylindrical coordinates and how this lattice has been incorporated within an 80 mm diameter mirror intended for use in a 3U CubeSat telescope. Several design iterations are explored, which include prototype mirrors produced in a titanium alloy and a finite element analysis of the one of the design iterations

Co-limitation towards lower latitudes shapes global forest diversity gradients

The latitudinal diversity gradient (LDG) is one of the most recognized global patterns of species richness exhibited across a wide range of taxa. Numerous hypotheses have been proposed in the past two centuries to explain LDG, but rigorous tests of the drivers of LDGs have been limited by a lack of high-quality global species richness data. Here we produce a high-resolution (0.025° × 0.025°) map of local tree species richness using a global forest inventory database with individual tree information and local biophysical characteristics from ~1.3 million sample plots. We then quantify drivers of local tree species richness patterns across latitudes. Generally, annual mean temperature was a dominant predictor of tree species richness, which is most consistent with the metabolic theory of biodiversity (MTB). However, MTB underestimated LDG in the tropics, where high species richness was also moderated by topographic, soil and anthropogenic factors operating at local scales. Given that local landscape variables operate synergistically with bioclimatic factors in shaping the global LDG pattern, we suggest that MTB be extended to account for co-limitation by subordinate drivers

Southern African Large Telescope Spectroscopy of BL Lacs for the CTA project

In the last two decades, very-high-energy gamma-ray astronomy has reached maturity: over 200 sources have been detected, both Galactic and extragalactic, by ground-based experiments. At present, Active Galactic Nuclei (AGN) make up about 40% of the more than 200 sources detected at very high energies with ground-based telescopes, the majority of which are blazars, i.e. their jets are closely aligned with the line of sight to Earth and three quarters of which are classified as high-frequency peaked BL Lac objects. One challenge to studies of the cosmological evolution of BL Lacs is the difficulty of obtaining redshifts from their nearly featureless, continuum-dominated spectra. It is expected that a significant fraction of the AGN to be detected with the future Cherenkov Telescope Array (CTA) observatory will have no spectroscopic redshifts, compromising the reliability of BL Lac population studies, particularly of their cosmic evolution. We started an effort in 2019 to measure the redshifts of a large fraction of the AGN that are likely to be detected with CTA, using the Southern African Large Telescope (SALT). In this contribution, we present two results from an on-going SALT program focused on the determination of BL Lac object redshifts that will be relevant for the CTA observatory

Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).

Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and ≥1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (n = 5069) or prospectively (n = 5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (≤6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; p = 0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)