384 research outputs found
The earliest evidence of true lambdoid craniosynostosis: the case of “Benjamina”, a Homo heidelbergensis child
Background The authors report the morphological and
neuroimaging findings of an immature human fossil
(Cranium 14) diagnosed with left lambdoid synostosis.
Discussion The skull was recovered at the Sima de los
Huesos site in Atapuerca (Burgos, Spain). Since the human
fossil remains from this site have been dated to a minimum
age of 530,000 years, this skull represents the earliest
evidence of craniosynostosis occurring in a hominid. A
brief historical review of craniosynostosis and cranial
deformation is provided
SmartLET: learning analytics to enhance the design and orchestration in scalable, IoT-enriched, and ubiquitous Smart Learning Environments
Proceeding of: 6th International Conference on Technological Ecosystems for Enhancing Multiculturality (TEEM 2018), Salamanca, Spain, 24-26 October 2018This paper presents the SmartLET project, a coordinated research project funded by the Spanish Ministry of Science, Innovation and Universities, which just started in 2018. The main aim of this project is to provide support for the design and orchestration of Smart Learning Environments (SLEs) with the support of learning analytics and the Internet of Things. This paper gives an overview of our conception of SLEs based on previous works, provides some ideas about the connection of learning design and orchestration with SLEs, and analyses different ethical and privacy issues for SLEs. In addition, an initial hypothesis and some specific objectives for a support environment for SLEs are proposed
Studing audition in fossil hominins: a new approach to the evolution of language?
The evolution of human language is one of the oldest questions inpaleoanthropology. Nevertheless, many previous attempts to approachthis question have not yielded informative results since they are oftenbased on anatomical features whose role in speech production in modernhumans is unclear or whose functional implications in fossil specimensare difficult to assess. We take a new approach to this question bystudying the evolution of audition. Human hearing differs from that ofchimpanzees and other primate taxa in maintaining a widened bandwidthof heightened sensitivity between 1-8 kHz, a region that contains relevantacoustic information in spoken language. Comparative analysis ofprimate audiograms suggests that this represents a unique derived featurein modern humans. Knowledge of the auditory capacities in our fossilhuman ancestors could greatly enhance the understanding of when thishuman pattern emerged during the course of our evolutionary history.Here we present a comprehensive approach to this question, onlyrarely addressed in human evolutionary studies. We have analyzed theauditory capacities in five fossil human specimens from the MiddlePleistocene site of the Sima de los Huesos (SH) in the Sierra deAtapuerca of Spain. The results demonstrate that the Atapuerca (SH)hominins resemble modern humans in showing a widened bandwidth ofheightened sensitivity between 1-5 kHz, a frequency range whichoverlaps the range of frequencies emitted during spoken language. At thesame time, both modern humans and the Atapuerca (SH) hominins differfrom chimpanzees in showing a heightened sensitivity to the highconsonant area (approximately 3-5 kHz) of the so-called "speechbanana", a frequency range associated with consonant production inhuman spoken language.The presence of a modern human auditory pattern in the Atapuercahominins suggests that these Middle Pleistocene humans alreadypossessed the anatomical features of the outer and middle ear that supportthe perception of human spoken language. Given the intuitive, butdifficult to quantify, link between sound perception and vocal productionin animals, the study of auditory capacities may have implications for theemergence of language in our fossil human ancestors. Although the studyof audition is an indirect approach to the question of speech capacity infossil specimens, the results of the present study are consistent with otherrecent suggestions for the presence of some form of spoken language inthe genus Homo prior to the appearance of our own species, Homosapiens
Investigation of enhanced thermal properties in NiO-based nanofluids for concentrating solar power applications: A molecular dynamics and experimental analysis
Nanofluids could be a promising alternative to the typical heat transfer fluids (HTF) used in concentrating solar power. This study analyses nanofluids based on a typical HTF for concentrating solar power (CSP) applications and NiO nanoparticles. The optimum nanoparticle concentration was determined by analysing the stability of the nanofluids. Some of their properties, such as density, viscosity, isobaric specific heat and thermal con- ductivity, were characterized to evaluate their performance. Their thermal conductivity increased by up to 96% and the heat transfer coefficient by 50%. Molecular dynamics calculations were performed to explain from a molecular perspective how the presence of equal proportions of two surfactants, benzalkonium chloride (BAC) and 1-Octadecanethiol (ODT), enhanced the thermal properties of the NiO nanofluid. The isobaric specific heat and thermal conductivity values followed the same experimental tendency. The analysis of the radial distribu- tion functions (RDFs) and spatial distribution functions (SDFs) revealed an inner layer of base fluid and sur- factant molecules around the NiO cell. This first layer contained BAC molecules at all the temperatures, while ODT was only incorporated at higher temperatures. The exchange of surfactant and base fluid molecules around the NiO as the temperature increases may play an important role in the enhancement of the thermal properties
MoS2 nanosheets vs nanowires: preparation and theoretical study of highly stable and efficient nanofluids for Concentrating Solar Power
The nano-colloidal suspension of nanomaterials in a base fluid, typically named a nanofluid, is a promising system that shows interesting properties, such as those related to heat transfer processes. Obtaining nanofluids with high stability is a priority challenge for this kind of system. So, a rationalization of the preparation of nanofluids is clearly needed. Thus, this study presents a methodology based on liquid phase exfoliation that makes it possible to prepare stable nanofluids and control the morphology of the nanostructures, which is defined by the surfactant used. Two stable nanofluids were prepared based on MoS2 nanosheets and MoS2 nanowires and a typical heat transfer fluid (HTF) used in high temperature applications. Periodic-Density Functional Theory (periodic-DFT) calculations were performed to rationalize why different nanostructures were obtained according to the surfactant used. Finally, enhancements in thermal properties were found, being up to 57% for thermal conductivity and up to 7.5% for isobaric specific heat. Therefore, these nanofluids are a promising alternative to the typical HTF used, which is a eutectic mixture of biphenyl and diphenyl oxide. Also, to our knowledge, controlling the nanostructures obtained and the rationalization of the methodology for the preparation of stable nanofluids is reported for the first time. This leads to highly stable nanofluids with improved thermal properties, promising for application in concentrating solar power
Human remains from Valdegoba Cave (Huérmeces, Burgos, Spain)
Systematic excavations, begun in 1987, at the Valdegoba cave site in
northern Spain have yielded the remains of five individuals associated
with a Middle Paleolithic stone tool technology and Pleistocene
fauna. A fragmentary mandible of an adolescent (VB1), preserving
nearly a full set of teeth, exhibits a symphyseal tubercle and slight
incurvatio mandibulae anterior on the external symphysis. Both the
superior and inferior transverse tori are present on the internal aspect.
A second individual (VB2) is represented by a set of ten deciduous
teeth consistent with an age at death of 6–9 months. A proximal
manual phalanx (VB3) displays a relatively broad head, a characteristic
which is found in both Neandertals, as well as European Middle
Pleistocene hominids. VB4 is a fourth metatarsal that lacks the distal
epiphysis, indicating it comes from an adolescent individual, and has
a relatively high robusticity index. Finally, VB5 is a fifth metatarsal of
an adult. The VB1 mandible shows a combination of archaic characteristics
as well as more specific Neandertal morphological traits. The
VB2 deciduous teeth are very small, and both the metrics and
morphology seem more consistent with a modern human classification.
The postcranial elements are undiagnostic, U-Th dating has
provided an age of >350 ka for the base of the sequence and a date of
<73·2 ± �5 ka for level 7, near the top. Faunal analysis and radiometric
dates from other nearby Mousterian sites suggests that the Valdegoba
site is correlative with oxygen isotope stages 3–6 on the Iberian
peninsula, and an Upper Pleistocene age for the Valdegoba hominids
seems most reasonable
Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector
A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results
Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)
Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters.
Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs).
Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001).
Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio
Juxtaposing BTE and ATE – on the role of the European insurance industry in funding civil litigation
One of the ways in which legal services are financed, and indeed shaped, is through private insurance arrangement. Two contrasting types of legal expenses insurance contracts (LEI) seem to dominate in Europe: before the event (BTE) and after the event (ATE) legal expenses insurance. Notwithstanding institutional differences between different legal systems, BTE and ATE insurance arrangements may be instrumental if government policy is geared towards strengthening a market-oriented system of financing access to justice for individuals and business. At the same time, emphasizing the role of a private industry as a keeper of the gates to justice raises issues of accountability and transparency, not readily reconcilable with demands of competition. Moreover, multiple actors (clients, lawyers, courts, insurers) are involved, causing behavioural dynamics which are not easily predicted or influenced.
Against this background, this paper looks into BTE and ATE arrangements by analysing the particularities of BTE and ATE arrangements currently available in some European jurisdictions and by painting a picture of their respective markets and legal contexts. This allows for some reflection on the performance of BTE and ATE providers as both financiers and keepers. Two issues emerge from the analysis that are worthy of some further reflection. Firstly, there is the problematic long-term sustainability of some ATE products. Secondly, the challenges faced by policymakers that would like to nudge consumers into voluntarily taking out BTE LEI
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