4,452 research outputs found
Rediscovering Cova de la Sarsa (València, Spain): a Multidisciplinary Approach to One of the Key Early Neolithic Sites in the Western Mediterranean
Cova de la Sarsa (València, Spain) is one of the most important Neolithic impressed ware culture archaeological sites in the Western Mediterranean. It has been widely referenced since it was excavated in the 1920s, due partly to the relatively early excavation and publication of the site, and partly to the qualitative and quantitative importance of its archaeological remains. Unfortunately, as it was an older excavation and lacked present-day rigorous methodological approaches, this important site has been somewhat relegated to the background in the reviews about the Neolithic at the end of the 20th century. However, during the last few years, both the site itself and its archaeological remains have been the object of new studies that hopefully will return the site to the forefront of discussions about the Mediterranean Neolithic. We here present the most relevant results of the research carried out by our group (i.e., pottery study, radiocarbon dating, and isotope analysis), and contextualize them within the dense research history of the cave and the studies carried out by other colleagues with the purpose of revisiting its materials and increasing the knowledge available from the site. Radiocarbon dates on human remains show that the cave was used during prehistoric times as a funerary space longer than expected, and also sporadically afterwards. The characterization of the pottery assemblage concludes that most materials belong to the Early Neolithic. Isotopic analysis portrays an overall similar diet based on terrestrial C3 resources throughout prehistoric times, with a possible varied dietary protein input between individuals during the Early Neolithic
Acquisition scenario analysis for face recognition at a distance
The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-642-17289-2_44Proceedings of 6th International Symposium, ISVC 2010, Las Vegas, NV, (USA)An experimental analysis of three acquisition scenarios for face recognition at a distance is reported, namely: close, medium, and far distance between camera and query face, the three of them considering templates enrolled in controlled conditions. These three representative scenarios are studied using data from the NIST Multiple Biometric Grand Challenge, as the first step in order to understand the main variability factors that affect face recognition at a distance based on realistic yet workable and widely available data. The scenario analysis is conducted quantitatively in two ways. First, we analyze the information content in segmented faces in the different scenarios. Second, we analyze the performance across scenarios of three matchers, one commercial, and two other standard approaches using popular features (PCA and DCT) and matchers (SVM and GMM). The results show to what extent the acquisition setup impacts on the verification performance of face recognition at a distance.This work has been partially supported by projects Bio-Challenge (TEC2009-11186), Contexts (S2009/TIC-1485), TeraSense (CSD2008-00068) and "Cátedra UAM-Telefónica"
Zero-lag long-range synchronization via dynamical relaying
We show that simultaneous synchronization between two delay-coupled
oscillators can be achieved by relaying the dynamics via a third mediating
element, which surprisingly lags behind the synchronized outer elements. The
zero-lag synchronization thus obtained is robust over a considerable parameter
range. We substantiate our claims with experimental and numerical evidence of
these synchronization solutions in a chain of three coupled semiconductor
lasers with long inter-element coupling delays. The generality of the mechanism
is validated in a neuronal model with the same coupling architecture. Thus, our
results show that synchronized dynamical states can occur over long distances
through relaying, without restriction by the amount of delay.Comment: 10 pages, 4 figure
The Relationship between Visual-Spatial and Auditory-Verbal Working Memory Span in Senegalese and Ugandan Children
BACKGROUND: Using the Kaufman Assessment Battery for Children (K-ABC) Conant et al. (1999) observed that visual and auditory working memory (WM) span were independent in both younger and older children from DR Congo, but related in older American children and in Lao children. The present study evaluated whether visual and auditory WM span were independent in Ugandan and Senegalese children. METHOD: In a linear regression analysis we used visual (Spatial Memory, Hand Movements) and auditory (Number Recall) WM along with education and physical development (weight/height) as predictors. The predicted variable in this analysis was Word Order, which is a verbal memory task that has both visual and auditory memory components. RESULTS: Both the younger (<8.5 yrs) and older (>8.5 yrs) Ugandan children had auditory memory span (Number Recall) that was strongly predictive of Word Order performance. For both the younger and older groups of Senegalese children, only visual WM span (Spatial Memory) was strongly predictive of Word Order. Number Recall was not significantly predictive of Word Order in either age group. CONCLUSIONS: It is possible that greater literacy from more schooling for the Ugandan age groups mediated their greater degree of interdependence between auditory and verbal WM. Our findings support those of Conant et al., who observed in their cross-cultural comparisons that stronger education seemed to enhance the dominance of the phonological-auditory processing loop for WM
Degradable high Tg sugar-derived polycarbonates from isosorbide and dihydroxyacetone
Polycarbonates from isosorbide and dihydroxyacetone (DHA) have been synthesised using organocatalytic step-growth polymerization of their corresponding diols and bis-carbonylimidazolide monomers. By the choice of the feed ratio and monomer activation, either isosorbide or ketal protected DHA, random and alternating poly(Iso-co-DHA) carbonates have been formed. Thermal properties by DSC and TGA were herein strongly correlated to the monomer composition. Dilution studies using 1H-NMR spectroscopy of a model compound DHA-diethyl carbonate in CD3CN and D2O highlighted the influence of alfa-substituents on the keto/hydrate equilibrium of DHA. Further kinetics studies in the pH* range of 4.7 to 9.6 serve to show the hydrolytic pH-profile of DHA-carbonates. The hydrolytic degradation of deprotected polymer pellets shows an increased degradation with increasing DHA content. Pellets with a random or alternating configuration show different characteristics in terms of mass loss and molecular weight loss profile over time
Perfect Cluster States from Imperfect Global Entanglement
The cluster state, the highly entangled state that is the central resource
for one-way quantum computing, can be efficiently generated in a variety of
physical implementations via global nearest-neighbor interactions. In practice,
a systematic phase error is expected in the entangling process, resulting in
imperfect cluster states. We present a stochastic measurement technique to
generate large perfect cluster states and other graph states with high
probability from imperfect cluster states even when their initial entanglement
is weak.Comment: 16 pages IOP style, 4 EPS figures; major revisions to the strategy
for growth of cluster states, 2 new figures, several new references; accepted
for publication in NJ
De la prospección sistemática al laboratorio GIS en La Canal de Navarrés
El trabajo que presentamos se ha desarrollado en el marco del proyecto NSF “The Emergence of Coupled Natural and Human Landscapes in the Western Mediterranean”, en el área comprendida por la actual comarca de La Canal de Navarres. Este espacio se convierte en uno de las áreas elegidas para un programa de recogida de datos centrado en la prospección sistemática “off site “  o “patch-based” (Barton et al. 2004; Dunnell 1992). Los datos relativos a la cultura material se combinan con la información espacial y ecológica, lo cual permite una comprensión dinámica de los mismos
Elasticity Theory Connection Rules for Epitaxial Interfaces
Elasticity theory provides an accurate description of the long-wavelength
vibrational dynamics of homogeneous crystalline solids, and with supplemental
boundary conditions on the displacement field can also be applied to abrupt
heterojunctions and interfaces. The conventional interface boundary conditions,
or connection rules, require that the displacement field and its associated
stress field be continuous through the interface. We argue, however, that these
boundary conditions are generally incorrect for epitaxial interfaces, and we
give the general procedure for deriving the correct conditions, which depend
essentially on the detailed microscopic structure of the interface. As a simple
application of our theory we analyze in detail a one-dimensional model of an
inhomogeneous crystal, a chain of harmonic oscillators with an abrupt change in
mass and spring stiffness parameters. Our results have implications for phonon
dynamics in nanostructures such as superlattices and nanoparticles, as well as
for the thermal boundary resistance at epitaxial interfaces.Comment: 7 pages, Revte
Screening for Gynecologic Conditions With Pelvic Examination US Preventive Services Task Force Recommendation Statement
IMPORTANCE Many conditions that can affect women\u27s health are often evaluated through pelvic examination. Although the pelvic examination is a common part of the physical examination, it is unclear whether performing screening pelvic examinations in asymptomatic women has a significant effect on disease morbidity and mortality. OBJECTIVE To issue a new US Preventive Services Task Force(USPSTF) recommendation on screening for gynecologic conditions with pelvic examination for conditions other than cervical cancer, gonorrhea, and chlamydia, for which the USPSTF has already made specific recommendations. EVIDENCE REVIEW The USPSTF reviewed the evidence on the accuracy, benefits, and potential harms of performing screening pelvic examinations in asymptomatic, nonpregnant adult women 18 years and older who are not at increased risk for any specific gynecologic condition. FINDINGS Overall, the USPSTF found inadequate evidence on screening pelvic examinations for the early detection and treatment of a range of gynecologic conditions in asymptomatic, nonpregnant adult women. CONCLUSIONS AND RECOMMENDATION The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of performing screening pelvic examinations in asymptomatic, nonpregnant adult women. (I statement) This statement does not apply to specific disorders for which the USPSTF already recommends screening (ie, screening for cervical cancer with a Papanicolaou smear, screening for gonorrhea and chlamydia)
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