238 research outputs found

    Estudio bioarqueológico de una población prehispánica lacustre del Valle de Toluca durante el horizonte epiclásico

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    El patrimonio arqueológico representa uno de los recursos más importantes para la recuperación de información relativa al devenir histórico de las sociedades que ocuparon el territorio nacional antes de la Conquista española. En cada sitio arqueológico se tiene una valiosa oportunidad para rescatar información relativa a procesos que permitieron la conformación de sociedades complejas que evolucionaron a lo largo de cientos de años. Desafortunadamente el vertiginoso desarrollo de la sociedad moderna, que se observa en el crecimiento desmedido de las áreas urbanas, destruye gran cantidad de sitios con la consiguiente pérdida de datos que nos dejan una visión fragmentaria, a veces poco comprensible. En virtud de lo anterior, es imprescindible realizar trabajos en el Valle de Toluca, que permitan la localización y registro de asentamientos a fin de contar con una base de datos que nos acerquen al conocimiento de la salud en poblaciones antiguas.El patrimonio arqueológico representa uno de los recursos más importantes para la recuperación de información relativa al devenir histórico de las sociedades que ocuparon el territorio nacional antes de la Conquista española. En cada sitio arqueológico se tiene una valiosa oportunidad para rescatar información relativa a procesos que permitieron la conformación de sociedades complejas que evolucionaron a lo largo de cientos de años. Desafortunadamente el vertiginoso desarrollo de la sociedad moderna, que se observa en el crecimiento desmedido de las áreas urbanas, destruye gran cantidad de sitios con la consiguiente pérdida de datos que nos dejan una visión fragmentaria, a veces poco comprensible. En virtud de lo anterior, es imprescindible realizar trabajos en el Valle de Toluca, que permitan la localización y registro de asentamientos a fin de contar con una base de datos que nos acerquen al conocimiento de la salud en poblaciones antiguas

    A Comparative Study of Age-Related Hearing Loss in Wild Type and Insulin-Like Growth Factor I Deficient Mice

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    Insulin-like growth factor-I (IGF-I) belongs to the family of insulin-related peptides that fulfils a key role during the late development of the nervous system. Human IGF1 mutations cause profound deafness, poor growth and mental retardation. Accordingly, Igf1−/− null mice are dwarfs that have low survival rates, cochlear alterations and severe sensorineural deafness. Presbycusis (age-related hearing loss) is a common disorder associated with aging that causes social and cognitive problems. Aging is also associated with a decrease in circulating IGF-I levels and this reduction has been related to cognitive and brain alterations, although there is no information as yet regarding the relationship between presbycusis and IGF-I biodisponibility. Here we present a longitudinal study of wild type Igf1+/+ and null Igf1−/− mice from 2 to 12 months of age comparing the temporal progression of several parameters: hearing, brain morphology, cochlear cytoarchitecture, insulin-related factors and IGF gene expression and IGF-I serum levels. Complementary invasive and non-invasive techniques were used, including auditory brainstem-evoked response (ABR) recordings and in vivo MRI brain imaging. Igf1−/− null mice presented profound deafness at all the ages studied, without any obvious worsening of hearing parameters with aging. Igf1+/+ wild type mice suffered significant age-related hearing loss, their auditory thresholds and peak I latencies augmenting as they aged, in parallel with a decrease in the circulating levels of IGF-I. Accordingly, there was an age-related spiral ganglion degeneration in wild type mice that was not evident in the Igf1 null mice. However, the Igf1−/− null mice in turn developed a prematurely aged stria vascularis reminiscent of the diabetic strial phenotype. Our data indicate that IGF-I is required for the correct development and maintenance of hearing, supporting the idea that IGF-I-based therapies could contribute to prevent or ameliorate age-related hearing loss

    Ibérico (Iberian) Pig

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    The main characteristics of the Iberian breed, an autochthonous pig breed of the Iberian Peninsula, are presented in this chapter along with the results of a literature review on productive traits. Reproductive performance was estimated by sow age at first parturition, litters per sow and year, piglets alive per litter, piglet weight at birth and at weaning, percentage of stillborn per litter, mortality at weaning, lactation length and farrowing interval. For growth performance, average daily gain and daily feed intake during lactation and in different growing phases are provided. Carcass traits were evaluated by age and weight at slaughter, hot carcass weight, carcass yield, backfat thickness measurements, muscle thickness and loin eye area. Meat quality traits of longissimus muscle (pH, objective colour measurements and intramuscular fat) were also assessed. The main part of the studies considered simulated practical production conditions in Iberian pig rearing although others evaluated a defined growing period, sometimes quite far from the usual commercial slaughter weight of this breed. Therefore, some figures should be interpreted with caution. Although a considerable number of studies on Iberian pig were included in the current review, scientific papers on reproductive performance and some meat quality parameters are still rather scarce

    Can evidence change belief ? Reported mobile phone sensitivity following individual feedback of an inability to discriminate active from sham signals

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    Abstract Objective: In this study, we tested whether providing individuals, who described being sensitive to mobile phone signals, with accurate feedback about their ability to discriminate an active mobile phone signal from a sham signal had any impact on their subsequent symptom levels or their perceived sensitivity to mobile phones. Methods: Sixty-nine participants who reported sensitivity to mobile phones took part in a doubleblind, placebo-controlled provocation study. Perceived sensitivity to mobile phones was assessed using a version of the Sensitive Soma Assessment Scale (SSAS) and the severity of any symptoms attributed to mobile phones was recorded. Both the overall ("negative") findings of the provocation study and the participant's own individual results ("correct" or "incorrect" at detecting a mobile phone signal) were then described to them. Six months later, perceived sensitivity and symptom severity were measured again. Results: Fifty-eight participants (84%) received feedback and participated in the 6-month follow-up. No significant differences in SSAS scores or in symptom severity scores were found between individuals told that they were correct (n=31) or incorrect (n=27) in their ability to detect mobile phone signals in the provocation study. Conclusion: The provision of accurate feedback was insufficient to change attributions or reduce symptoms in this study. However, an overtly negative reaction to feedback was not observed among most participants, and some participants were willing to consider that factors other than electromagnetic field may be relevant in causing or exacerbating their symptoms. Discussing possible psychological factors with electromagnetic hypersensitivity patients may be beneficial for some

    Local Pig Breeds: Nutritional Requirements, Innovative Practices and Local Feeding Resources as Challenges in Project TREASURE

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    TREASURE is a research and innovation project of European Union’s Horizon 2020 programme which is devoted to traditional genetic resources in pig production with aim to improve their potentials for enhanced use. Studying and improving management of local pig breeds in their production systems is one of the challenges in which we address their performances and nutrition with special attention on locally available feeding resources and innovative practices aiming to improved welfare. For that purpose 15 experiments on 12 breeds were designed in the project, which are hereafter shortly presented. Their concepts and main objectives with some highlights on already available results are described

    Enfrentando los riesgos socionaturales

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    El objetivo del libro es comprender la magnitud de los Riesgos Socionaturales en México y Latinoamérica, para comprender el peligro que existe por algún tipo de desastre, ya sea inundaciones, sismos, remoción en masa, entre otros, además conocer qué medidas preventivas, correctivas y de contingencias existen para estar atentos ante alguna señal que la naturaleza esté enviando y así evitar alguna catástrofe. El libro se enfoca en los aspectos básicos de análisis de los peligros, escenarios de riesgo, vulnerabilidad y resiliencia, importantes para la gestión prospectiva o preventiva

    Gamma/Hadron Separation with the HAWC Observatory

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    The High Altitude Water Cherenkov (HAWC) gamma-ray observatory observesatmospheric showers produced by incident gamma rays and cosmic rays with energyfrom 300 GeV to more than 100 TeV. A crucial phase in analyzing gamma-raysources using ground-based gamma-ray detectors like HAWC is to identify theshowers produced by gamma rays or hadrons. The HAWC observatory records roughly25,000 events per second, with hadrons representing the vast majority(>99.9%>99.9\%) of these events. The standard gamma/hadron separation technique inHAWC uses a simple rectangular cut involving only two parameters. This workdescribes the implementation of more sophisticated gamma/hadron separationtechniques, via machine learning methods (boosted decision trees and neuralnetworks), and summarizes the resulting improvements in gamma/hadron separationobtained in HAWC.<br

    Validation of standardized data formats and tools for ground-level particle-based gamma-ray observatories

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    Ground-based gamma-ray astronomy is still a rather young field of research,with strong historical connections to particle physics. This is why mostobservations are conducted by experiments with proprietary data and analysissoftware, as it is usual in the particle physics field. However in recentyears, this paradigm has been slowly shifting towards the development and useof open-source data formats and tools, driven by upcoming observatories such asthe Cherenkov Telescope Array (CTA). In this context, a community-driven,shared data format (the gamma-astro-data-format or GADF) and analysis toolssuch as Gammapy and ctools have been developed. So far these efforts have beenled by the IACT community, leaving out other types of ground-based gamma-rayinstruments.We aim to show that the data from ground particle arrays, such asthe High-Altitude Water Cherenkov (HAWC) observatory, is also compatible withthe GADF and can thus be fully analysed using the related tools, in this caseGammapy. We reproduce several published HAWC results using Gammapy and dataproducts compliant with GADF standard. We also illustrate the capabilities ofthe shared format and tools by producing a joint fit of the Crab spectrumincluding data from six different gamma-ray experiments. We find excellentagreement with the reference results, a powerful check of both the publishedresults and the tools involved. The data from particle detector arrays such asthe HAWC observatory can be adapted to the GADF and thus analysed with Gammapy.A common data format and shared analysis tools allow multi-instrument jointanalysis and effective data sharing. Given the complementary nature of pointingand wide-field instruments, this synergy will be distinctly beneficial for thejoint scientific exploitation of future observatories such as the SouthernWide-field Gamma-ray Observatory and CTA.<br

    The TeV Sun Rises: Discovery of Gamma rays from the Quiescent Sun with HAWC

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    We report the first detection of a TeV gamma-ray flux from the solar disk (6.3σ\sigma), based on 6.1 years of data from the High Altitude Water Cherenkov (HAWC) observatory. The 0.5--2.6 TeV spectrum is well fit by a power law, dN/dE = A(E/1 TeV)γA (E/1 \text{ TeV})^{-\gamma}, with A=(1.6±0.3)×1012A = (1.6 \pm 0.3) \times 10^{-12} TeV1^{-1} cm2^{-2} s1^{-1} and γ=3.62±0.14\gamma = -3.62 \pm 0.14. The flux shows a strong indication of anticorrelation with solar activity. These results extend the bright, hard GeV emission from the disk observed with Fermi-LAT, seemingly due to hadronic Galactic cosmic rays showering on nuclei in the solar atmosphere. However, current theoretical models are unable to explain the details of how solar magnetic fields shape these interactions. HAWC's TeV detection thus deepens the mysteries of the solar-disk emission.Comment: 15 pages, 8 figures including supplementary material. Accepted for publication in Physical Review Letter

    HAWC Study of Very-High-Energy γ\gamma-ray Spectrum of HAWC J1844-034

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    Recently, the region surrounding eHWC J1842-035 has been studied extensively by gamma-ray observatories due to its extended emission reaching up to a few hundred TeV and potential as a hadronic accelerator. In this work, we use 1,910 days of cumulative data from the High Altitude Water Cherenkov (HAWC) observatory to carry out a dedicated systematic source search of the eHWC J1842-035 region. During the search we have found three sources in the region, namely, HAWC J1844-034, HAWC J1843-032, and HAWC J1846-025. We have identified HAWC J1844-034 as the extended source that emits photons with energies up to 175 TeV. We compute the spectrum for HAWC J1844-034 and by comparing with the observational results from other experiments, we have identified HESS J1843-033, LHAASO J1843-0338, and TASG J1844-038 as very-high-energy gamma-ray sources with a matching origin. Also, we present and use the multi-wavelength data to fit the hadronic and leptonic particle spectra. We have identified four pulsar candidates in the nearby region from which PSR J1844-0346 is found to be the most likely candidate due to its proximity to HAWC J1844-034 and the computed energy budget. We have also found SNR G28.6-0.1 as a potential counterpart source of HAWC J1844-034 for which both leptonic and hadronic scenarios are feasible.Comment: 13 pages, 9 figures, published in Ap
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