609 research outputs found

    ESTRUCTURA ESPACIO‐TEMPORAL DE LA DIVERSIDAD TAXONÓMICA Y FUNCIONAL DE COLIBRÍES EN LA RESERVA DE LA BIOSFERA EL TRIUNFO, CHIAPAS, MÉXICO

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    RESUMEN ∙ La diversidad taxonómica y funcional de las comunidades de aves está determinada por la distribución espacio‐temporal y la densidad de las poblaciones de las especies que las integran. La diversidad puede variar según el gradiente de elevación, en general al aumentar la elevación se reduce la riqueza de especies, como es el caso en algunas comunidades de colibríes (Trochilidae). En este estudio se evaluó la distribución, la densidad, la diversidad taxonómica y funcional de tres comunidades de colibríes en diferentes elevaciones y temporadas en la Reserva de la Biosfera El Triunfo, Chiapas, México. Establecimos transectos en tres elevaciones (300 a 2500 m s.n.m.), los cuales se recorrieron durante tres temporadas (secas, lluvias y post‐lluvias) de 2015 a 2016. Asimismo, obtuvimos datos morfométricos de las especies para analizar rasgos funcionales (i.e., masa corporal, longitud y curvatura del pico) y evaluar la diversidad funcional de las comunidades. Los resultados indican que la mayor diversidad de colibríes ocurrió en la elevación media, y no hubo variación significativa de la diversidad entre temporadas. De acuerdo a los rasgos funcionales medidos, solo la masa corporal mostró diferencias con la altura, siendo mayor en elevaciones altas. Los valores de la diversidad funcional obtenidos fueron similares entre elevaciones, pero la divergencia fue mayor en la elevación baja, y la especialización fue mayor en elevaciones media y baja. Esto indica una diferenciación de nichos en la elevación baja y un efecto ambiental en la elevación alta, lo que estructuraría las comunidades de colibríes en nuestro sitio de estudio.Abstract ∙ Spatio‐temporal structure of the taxonomic and functional diversity of hummingbirds at the biosphere reserve El Triunfo, Chiapas, Mexico The taxonomic and functional diversity of bird communities is determined by the spatio‐temporal distribution and population density of their constitutive species. Diversity can change along environmental gradients and one of these patterns shows that as the elevation increases bird richness is reduced, as has been observed in some communities of hummingbirds. We evaluated the distribution, taxonomic and functional structure of three hummingbird (Trochilidae) communities at El Triunfo Biosphere Reserve, Chiapas, Mexico. We established transects where we performed counts at three elevations (300 to 2500 m a.s.l.) and during three seasons (dry, rainy, and post‐rainy) from 2015 to 2016. We also obtained morphometric data from the species to analyze functional traits (i.e., body mass, length, and curvature of the bill) and functional diversity. The results indicate that the highest species diversity of hummingbirds occurred at intermediate elevation, and that there was no significant variation in diversity among seasons. Out of the functional traits measured only body mass showed differences, being higher at high elevations. Functional diversity values were similar across elevations, but the divergence was higher at low elevations, and the degree of specialization was higher at medium and low elevations. This suggests a differentiation of niches at low elevations and an environmental filtering effect at high elevation, which structure hummingbird communities at our study site

    Anomalías de forma y número en dentición temporal en una población Mexicana

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    Objetivo: Determinar la frecuencia y distribución de las anomalías de forma y de número en dentición temporal.  Material y Métodos: Estudio retro-prolectivo, transversal y descriptivo. Muestreo probabilístico por conveniencia estratificado por género. Se revisaron 1568 expedientes de pacientes que acudieron a la Clínica de Estomatología Pediátrica de la FEBUAP, durante el periodo 2012 a 2014, se incluyeron 720 expedientes (321 niñas y 399 niños) de 1 a 10 años, que presentaron estudios radiográficos completos, nítidos, con presencia de anomalías de forma o número, el estudio fue dividido en pacientes activos e inactivos. Para los inactivos se tomaron fotografías de las radiografías con presencia de anomalías de forma y/o número. En el caso de los activos, se realizó una entrevista con alguno de los padres, se solicitó autorización bajo consentimiento informado, asentimiento por parte del niño para realizar la exploración clínica y la toma de fotografías intraorales. Resultados: En total 63 niños tuvieron anomalías (17 niñas y 46 niños). La prevalencia total de las anomalías dentarias fue de 9%, de los cuales el 3,1% fueron (dientes fusionados y geminados), 1,1% (agenesias) y 1,9% (supernumerarios), 1,3% (raíces supernumerarias), 0,27% (macrodoncia), 0,11% (microdoncia) y finalmente el 0,27% correspondió a (talón cuspídeo). Conclusiones: A pesar de que la prevalencia de estas anomalías no es alta, es importante el examen radiográfico de rutina para realizar un diagnóstico temprano y así aplicar las medidas preventivas correctas, para establecer el mejor plan de tratamiento

    Dynamical Patterns of Cattle Trade Movements

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    Despite their importance for the spread of zoonotic diseases, our understanding of the dynamical aspects characterizing the movements of farmed animal populations remains limited as these systems are traditionally studied as static objects and through simplified approximations. By leveraging on the network science approach, here we are able for the first time to fully analyze the longitudinal dataset of Italian cattle movements that reports the mobility of individual animals among farms on a daily basis. The complexity and inter-relations between topology, function and dynamical nature of the system are characterized at different spatial and time resolutions, in order to uncover patterns and vulnerabilities fundamental for the definition of targeted prevention and control measures for zoonotic diseases. Results show how the stationarity of statistical distributions coexists with a strong and non-trivial evolutionary dynamics at the node and link levels, on all timescales. Traditional static views of the displacement network hide important patterns of structural changes affecting nodes' centrality and farms' spreading potential, thus limiting the efficiency of interventions based on partial longitudinal information. By fully taking into account the longitudinal dimension, we propose a novel definition of dynamical motifs that is able to uncover the presence of a temporal arrow describing the evolution of the system and the causality patterns of its displacements, shedding light on mechanisms that may play a crucial role in the definition of preventive actions

    Dynamical Patterns of Cattle Trade Movements

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    Despite their importance for the spread of zoonotic diseases, our understanding of the dynamical aspects characterizing the movements of farmed animal populations remains limited as these systems are traditionally studied as static objects and through simplified approximations. By leveraging on the network science approach, here we are able for the first time to fully analyze the longitudinal dataset of Italian cattle movements that reports the mobility of individual animals among farms on a daily basis. The complexity and inter-relations between topology, function and dynamical nature of the system are characterized at different spatial and time resolutions, in order to uncover patterns and vulnerabilities fundamental for the definition of targeted prevention and control measures for zoonotic diseases. Results show how the stationarity of statistical distributions coexists with a strong and non-trivial evolutionary dynamics at the node and link levels, on all timescales. Traditional static views of the displacement network hide important patterns of structural changes affecting nodes' centrality and farms' spreading potential, thus limiting the efficiency of interventions based on partial longitudinal information. By fully taking into account the longitudinal dimension, we propose a novel definition of dynamical motifs that is able to uncover the presence of a temporal arrow describing the evolution of the system and the causality patterns of its displacements, shedding light on mechanisms that may play a crucial role in the definition of preventive actions

    VAMOS: a Pathfinder for the HAWC Gamma-Ray Observatory

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    VAMOS was a prototype detector built in 2011 at an altitude of 4100m a.s.l. in the state of Puebla, Mexico. The aim of VAMOS was to finalize the design, construction techniques and data acquisition system of the HAWC observatory. HAWC is an air-shower array currently under construction at the same site of VAMOS with the purpose to study the TeV sky. The VAMOS setup included six water Cherenkov detectors and two different data acquisition systems. It was in operation between October 2011 and May 2012 with an average live time of 30%. Besides the scientific verification purposes, the eight months of data were used to obtain the results presented in this paper: the detector response to the Forbush decrease of March 2012, and the analysis of possible emission, at energies above 30 GeV, for long gamma-ray bursts GRB111016B and GRB120328B.Comment: Accepted for pubblication in Astroparticle Physics Journal (20 pages, 10 figures). Corresponding authors: A.Marinelli and D.Zaboro

    Carbapenem-resistant Citrobacter spp. isolated in Spain from 2013 to 2015 produced a variety of carbapenemases including VIM-1, OXA-48, KPC-2, NDM-1 and VIM-2

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    Objectives: There is little information about carbapenemase-producing (CP) Citrobacter spp.We studied the molecular epidemiology and microbiological features of CP Citrobacter spp. isolates collected in Spain (2013-15). Methods: In total, 119 isolates suspected of being CP by the EUCAST screening cut-off values were analysed. Carbapenemases and ESBLs were characterized using PCR and sequencing. The genetic relationship among Citrobacter freundii isolates was studied by PFGE. Results: Of the 119 isolates, 63 (52.9%) produced carbapenemases, of which 37 (58.7%) produced VIM-1, 20 (31.7%) produced OXA-48, 12 (19%) produced KPC-2, 2 (3.2%) produced NDM-1 and 1 (1.6%) produced VIM- 2; 9 C. freundii isolates co-produced VIM-1 plus OXA-48. Fourteen isolates (22.2%) also carried ESBLs: 8 CTX-M-9 plus SHV-12, 2 CTX-M-9, 2 SHV-12 and 2 CTX-M-15. Fifty-seven isolates (90.5%) were C. freundii, 4 (6.3%) were Citrobacter koseri, 1 (1.6%) was Citrobacter amalonaticus and 1 (1.6%) was Citrobacter braakii. By EUCAST breakpoints, eight (12.7%) of the CP isolates were susceptible to the four carbapenems tested. In the 53 CP C. freundii analysed by PFGE, a total of 44 different band patterns were observed. Four PFGE clusters were identified: cluster 1 included eight isolates co-producing VIM-1 and OXA-48; blaVIM-1 was carried in a class 1 integron (intI-blaVIM-1 - aacA4-dfrB1-aadA1-catB2-qacE¿1/sul1) and blaOXA-48 was carried in a Tn1999.2 transposon. Conclusions: We observed the clonal and polyclonal spread of CP Citrobacter spp. across several Spanish geographical areas. Four species of Citrobacter spp. produced up to five carbapenemase types, including coproduction of VIM-1 plus OXA-48. Some CP Citrobacter spp. isolates were susceptible to the four carbapenems tested, a finding with potential clinical implications

    Anti-IL-6 Receptor Tocilizumab in Refractory Graves? Orbitopathy: National Multicenter Observational Study of 48 Patients

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    Graves’ orbitopathy (GO) is the most common extrathyroidal manifestation of Graves’ disease (GD). Our aim was to assess the e cacy and safety of Tocilizumab (TCZ) in GO refractory to conventional therapy. This was an open-label multicenter study of glucocorticoid-resistant GO treated with TCZ. The main outcomes were the best-corrected visual acuity (BVCA), Clinical Activity Score (CAS) and intraocular pressure (IOP). These outcome variables were assessed at baseline, 1st, 3rd, 6th and 12th month after TCZ therapy onset. The severity of GO was assessed according to the European Group on Graves’ Orbitopathy (EUGOGO). We studied 48 (38 women and 10 men) patients (95 eyes); mean age standard deviation 51 11.8 years. Before TCZ and besides oral glucocorticoids, they had received IV methylprednisolone (n = 43), or selenium (n = 11). GO disease was moderate (n =29) or severe (n = 19) and dysthyroid optic neuropathy (DON) (n = 7). TCZ was used in monotherapy (n = 45) or combined (n = 3) at a dose of 8 mg/kg IV every four weeks (n = 43) or 162 mg/s.c. every week (n = 5). TCZ yielded a significant improvement in all of the main outcomes at the 1st month that was maintained at one year. Comparing the baseline with data at 1 year all of the variables improved; BCVA (0.78 0.25 vs. 0.9 0.16; p = 0.0001), CAS (4.64 1.5 vs. 1.05 1.27; p = 0.0001) and intraocular pressure (IOP) (19.05 4.1 vs. 16.73 3.4 mmHg; p = 0.007). After a mean follow-up of 16.1 2.1 months, low disease activity (CAS 3), was achieved in 88 eyes (92.6%) and TCZ was withdrawn in 29 cases due to low disease activity (n = 25) or ine cacy (n = 4). No serious adverse events were observed. In conclusion, TCZ is a useful and safe therapeutic option in refractory GO treatment.This work was also partially supported by RETICS Programs, RD08/0075 (RIER) and RD12/0009/0013 from “Instituto de Salud Carlos III” (ISCIII) (Spain)

    Aspectos clínicos y epidemiológicos de los síndromes de Apert y Crouzon en España

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    Epidemiología y Teratología: Resultados sobre los datos del ECEMCApert and Crouzon syndromes are the most frequent ones among those syndromes with craniosynostosis. We have used data from the Spanish Collaborative Study of Congenital Malformations (ECEMC), to analyze some clinical and epidemiological characteristics of both syndromes. A total of 19 cases of Apert and 21 cases of Crouzon syndromes were identified among 1,914,726 liveborn infants. Their birth prevalence has diminished along the time although the decrease is only statistically significant for Crouzon syndrome. Mean parental ages, and mean differences between the parental ages, are significantly higher in Apert cases than in controls, what is indicating a relationship between paternal age and mutations for this syndrome. The differences between the parental ages of Crouzon cases and controls are not statistically significant. All the cases with Apert syndrome of our series were the first occurrence in the family, while 38.10% of the Crouzon cases were familial. We also observed a significant increasing linear trend in the frequency of infants with Apert syndrome, with the increasing paternal age, which is more noticeable since the age of 35 years. However, this is not observed for Crouzon cases whether sporadic or familial. Regarding the clinical aspects, Apert syndrome is more frequently associated to other defects than Crouzon syndrome. With respect to the affectation of hands in the Apert cases, the most frequent defect was the so-called "mitten hand", wich was present in 50% of our cases. In 28.57% the first finger was separated from the rest that are fused. Interestingly, in one case only the fifth finger was separated for the other four that remain fused.N

    Usefulness of bone turnover markers as predictors of mortality risk, disease progression and skeletal-related events appearance in patients with prostate cancer with bone metastases following treatment with zoledronic acid: TUGAMO study

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    Owing to the limited validity of clinical data on the treatment of prostate cancer (PCa) and bone metastases, biochemical markers are a promising tool for predicting survival, disease progression and skeletal-related events (SREs) in these patients. The aim of this study was to evaluate the predictive capacity of biochemical markers of bone turnover for mortality risk, disease progression and SREs in patients with PCa and bone metastases undergoing treatment with zoledronic acid (ZA). Methods: This was an observational, prospective and multicenter study in which ninety-eight patients were included. Patients were treated with ZA (4mg every 4 weeks for 18 months). Data were collected at baseline and 3, 6, 9, 12, 15 and 18 months after the beginning of treatment. Serum levels of bone alkaline phosphtase (BALP), aminoterminal propeptide of procollagen type I (P1NP) and beta-isomer of carboxiterminal telopeptide of collagen I (b-CTX) were analysed at all points in the study. Data on disease progression, SREs development and survival were recorded. Results: Cox regression models with clinical data and bone markers showed that the levels of the three markers studied were predictive of survival time, with b-CTX being especially powerful, in which a lack of normalisation in visit 1 (3 months after the beginning of treatment) showed a 6.3-times more risk for death than in normalised patients. Levels of these markers were also predictive for SREs, although in this case BALP and P1NP proved to be better predictors. We did not find any relationship between bone markers and disease progression. Conclusion: In patients with PCa and bone metastases treated with ZA, b-CTX and P1NP can be considered suitable predictors for mortality risk, while BALP and P1NP are appropriate for SREs. The levels of these biomarkers 3 months after the beginning of treatment are especially importantThis study was supported by Novartis Oncology Spai

    On the sensitivity of the HAWC observatory to gamma-ray bursts

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    We present the sensitivity of HAWC to Gamma Ray Bursts (GRBs). HAWC is a very high-energy gamma-ray observatory currently under construction in Mexico at an altitude of 4100 m. It will observe atmospheric air showers via the water Cherenkov method. HAWC will consist of 300 large water tanks instrumented with 4 photomultipliers each. HAWC has two data acquisition (DAQ) systems. The main DAQ system reads out coincident signals in the tanks and reconstructs the direction and energy of individual atmospheric showers. The scaler DAQ counts the hits in each photomultiplier tube (PMT) in the detector and searches for a statistical excess over the noise of all PMTs. We show that HAWC has a realistic opportunity to observe the high-energy power law components of GRBs that extend at least up to 30 GeV, as it has been observed by Fermi LAT. The two DAQ systems have an energy threshold that is low enough to observe events similar to GRB 090510 and GRB 090902b with the characteristics observed by Fermi LAT. HAWC will provide information about the high-energy spectra of GRBs which in turn could help to understanding about e-pair attenuation in GRB jets, extragalactic background light absorption, as well as establishing the highest energy to which GRBs accelerate particles
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