Diseño y cálculo de una pala cargadora para tractor agrícola

El proyecto consiste en realizar el diseño una pala cargadora para tractora agrícola así como una horquilla porta balas acoplable a esta. Las premisas fundamentales que deben cumplir el diseño es elevar una masa de 1.000 Kg a una altura máxima de 3,5 metros. Para realizar el diseño de las piezas ha sido realizado un estudio de mercado además se han estudiado las distintas soluciones adoptadas por otros fabricantes. Todas las piezas han sido dibujadas con el programa Autodesk Inventor. Tras el diseño de las piezas necesarias para el buen funcionamiento de la pala cargadora han sido comprobadas mediante programas de cálculo, como Solidworks

The impact of histopathology and NAB2-STAT6 fusion subtype in classification and grading of meningeal solitary fibrous tumor/hemangiopericytoma.

Meningeal solitary fibrous tumor (SFT)/hemangiopericytoma (HPC) is a rare tumor with propensity for recurrence and metastasis. Although multiple classification schemes have been proposed, optimal risk stratification remains unclear, and the prognostic impact of fusion status is uncertain. We compared the 2016 WHO CNS tumor grading scheme (CNS-G), a three-tier system based on histopathologic phenotype and mitotic count, to the 2013 WHO soft-tissue counterpart (ST-G), a two-tier system based on mitotic count alone, in a cohort of 133 patients [59 female, 74 male; mean age 54 years (range 20-87)] with meningeal SFT/HPC. Tumors were pathologically confirmed through review of the first tumor resection (n = 97), local recurrence (n = 35), or distant metastasis (n = 1). A STAT6 immunostain showed nuclear expression in 132 cases. NAB2-STAT6 fusion was detected in 99 of 111 successfully tested tumors (89%) including the single STAT6 immunonegative tumor. Tumors were classified by CNS-G as grade 1 (n = 43), 2 (n = 41), or 3 (n = 49), and by ST-G as SFT (n = 84) or malignant SFT (n = 49). Necrosis was present in 16 cases (12%). On follow-up, 42 patients had at least one subsequent recurrence or metastasis (7 metastasis only, 33 recurrence only, 2 patients had both). Twenty-nine patients died. On univariate analysis, necrosis (p = 0.002), CNS-G (p = 0.01), and ST-G (p = 0.004) were associated with recurrence-free (RFS) but not overall survival (OS). NAB2-STAT6 fusion type was not significantly associated with RFS or OS, but was associated with phenotype. A modified ST-G incorporating necrosis showed higher correlation with RFS (p = 0.0006) and remained significant (p = 0.02) when considering only the primary tumors. From our data, mitotic rate and necrosis appear to stratify this family of tumors most accurately and could be incorporated in a future grading scheme

Estrés percibido y felicidad auténtica a través del nivel de actividad física en jóvenes universitarios

Se ha demostrado en la literatura que el estrés y la felicidad se han relacionado de diversas maneras, y estas a su vez, también se relacionan con la práctica de actividad física (AF). El objetivo de este trabajo fue poner a prueba el papel de la AF en la reducción del estrés y el aumento de la felicidad, así como su rol mediador en la relación entre ambas variables. Concretamente, se pusieron a prueba las siguientes hipótesis: 1) la percepción del estrés (con o sin control de la situación estresante) y la felicidad auténtica difieren en función del nivel de AF; 2) a mayor práctica de AF, mayor percepción de control en la situación estresante y menor percepción de sentirse sobrepasado por la situación; 3) a mayor práctica de AF mayor felicidad auténtica; y 4) la relación entre la percepción del estrés (con o sin control de la situación estresante) y la felicidad auténtica está mediada por la AF. Participaron 938 estudiantes de licenciatura, con un rango de edad de 17 a 51 años (M= 20.25, DT= 3.34), 521 mujeres y 417 hombres. Respecto a la actividad física (AF) que realizan: 15.1% no realiza ninguna actividad; 19.7% realiza actividad irregular; 28% actividad física moderada (2hrs/sem); y 37.1% actividad intensa (20min/día, 5 veces/sem). Los participantes contestaron la PSS (Cohen, Kamarck, y Mermelstein, 1983) y el AHI (Shepherd, Oliver, y Schofield, 2015). Mediante análisis descriptivos, ANOVAs y modelos de regresión mediada se dio respuesta a las hipótesis. Los resultados muestran que la percepción del estrés (con o sin control de la situación estresante) y la felicidad auténtica difieren significativamente en función del nivel de AF. Concretamente, a mayor nivel de práctica de AF mayor percepción de control ante una situación estresante y mayor felicidad auténtica; mientras que a menor práctica de AF, mayor percepción de verse sobrepasado ante una situación estresante. Por último, el nivel de actividad física media la relación entre el estrés percibido (con control de la situación estresante y sin control de la situación estresante) y la felicidad auténtica. Con base enlos resultados concluimos que la AF ayuda a percibir un menor estrés ante situaciones demandantes, por lo que promueve un bienestar psicológico

Mechano-chemical kinetics of DNA replication: identification of the translocation step of a replicative DNA polymerase

[EN] During DNA replication replicative polymerases move in discrete mechanical steps along the DNA template. To address how the chemical cycle is coupled to mechanical motion of the enzyme, here we use optical tweezers to study the translocation mechanism of individual bacteriophage Phi29 DNA polymerases during processive DNA replication. We determine the main kinetic parameters of the nucleotide incorporation cycle and their dependence on external load and nucleotide (dNTP) concentration. The data is inconsistent with power stroke models for translocation, instead supports a loose-coupling mechanism between chemical catalysis and mechanical translocation during DNA replication. According to this mechanism the DNA polymerase works by alternating between a dNTP/PPi-free state, which diffuses thermally between pre- and post-translocated states, and a dNTP/PPi-bound state where dNTP binding stabilizes the post-translocated state. We show how this thermal ratchet mechanism is used by the polymerase to generate work against large opposing loads (~50 pN).We thank Stephan Grill laboratory (MPI-CBG, Dresden) for help with data collection and E. Galburt, M. Manosas and M. De Vega for critical reading of the manuscript. Spanish Ministry of Economy and Competitiveness [BFU2011-29038 to J.L.C., BFU2013-44202 to J.M.V., BFU2011-23645 to M.S., FIS2010-17440, GR35/10-A920GR35/10-A-911 to F.J.C., MAT2013-49455-EXP to J.R.A.-G. and BFU2012-31825 to B.I.]; Regional Government of Madrid [S2009/MAT 1507 to J.L.C. and CDS2007-0015 to M.S.]; European Molecular Biology Organization [ASTF 276-2012 to J.M.L.]. Funding for open access charge: Spanish Ministry of Economy and Competitiveness [BFU2012-31825 to B.I.].Morin, J.; Cao, F.; Lázaro, J.; Arias-Gonzalez, JR.; Valpuesta, J.; Carrascosa, J.; Salas, M.... (2015). 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The EMBO Journal, 25(15), 3458-3468. doi:10.1038/sj.emboj.7601211Zhang, H., Cao, W., Zakharova, E., Konigsberg, W., & De La Cruz, E. M. (2007). Fluorescence of 2-aminopurine reveals rapid conformational changes in the RB69 DNA polymerase-primer/template complexes upon binding and incorporation of matched deoxynucleoside triphosphates. Nucleic Acids Research, 35(18), 6052-6062. doi:10.1093/nar/gkm587Wang, W., Wu, E. Y., Hellinga, H. W., & Beese, L. S. (2012). Structural Factors That Determine Selectivity of a High Fidelity DNA Polymerase for Deoxy-, Dideoxy-, and Ribonucleotides. Journal of Biological Chemistry, 287(34), 28215-28226. doi:10.1074/jbc.m112.366609Berezhna, S. Y., Gill, J. P., Lamichhane, R., & Millar, D. P. (2012). Single-Molecule Förster Resonance Energy Transfer Reveals an Innate Fidelity Checkpoint in DNA Polymerase I. Journal of the American Chemical Society, 134(27), 11261-11268. doi:10.1021/ja3038273Hariharan, C., Bloom, L. B., Helquist, S. A., Kool, E. 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Trigger loop dynamics mediate the balance between the transcriptional fidelity and speed of RNA polymerase II. Proceedings of the National Academy of Sciences, 109(17), 6555-6560. doi:10.1073/pnas.1200939109Bar-Nahum, G., Epshtein, V., Ruckenstein, A. E., Rafikov, R., Mustaev, A., & Nudler, E. (2005). A Ratchet Mechanism of Transcription Elongation and Its Control. Cell, 120(2), 183-193. doi:10.1016/j.cell.2004.11.045Bai, L., Fulbright, R. M., & Wang, M. D. (2007). Mechanochemical Kinetics of Transcription Elongation. Physical Review Letters, 98(6). doi:10.1103/physrevlett.98.068103Abbondanzieri, E. A., Greenleaf, W. J., Shaevitz, J. W., Landick, R., & Block, S. M. (2005). Direct observation of base-pair stepping by RNA polymerase. Nature, 438(7067), 460-465. doi:10.1038/nature04268Dangkulwanich, M., Ishibashi, T., Liu, S., Kireeva, M. L., Lubkowska, L., Kashlev, M., & Bustamante, C. J. (2013). 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Disentangling signatures of selection before and after European colonization in latin Americans

Throughout human evolutionary history, large-scale migrations have led to intermixing (i.e., admixture) between previously separated human groups. Although classical and recent work have shown that studying admixture can yield novel historical insights, the extent to which this process contributed to adaptation remains underexplored. Here, we introduce a novel statistical model, specific to admixed populations, that identifies loci under selection while determining whether the selection likely occurred post-admixture or prior to admixture in one of the ancestral source populations. Through extensive simulations, we show that this method is able to detect selection, even in recently formed admixed populations, and to accurately differentiate between selection occurring in the ancestral or admixed population. We apply this method to genome-wide SNP data of ∼4,000 individuals in five admixed Latin American cohorts from Brazil, Chile, Colombia, Mexico, and Peru. Our approach replicates previous reports of selection in the human leukocyte antigen region that are consistent with selection post-admixture. We also report novel signals of selection in genomic regions spanning 47 genes, reinforcing many of these signals with an alternative, commonly used local-ancestry-inference approach. These signals include several genes involved in immunity, which may reflect responses to endemic pathogens of the Americas and to the challenge of infectious disease brought by European contact. In addition, some of the strongest signals inferred to be under selection in the Native American ancestral groups of modern Latin Americans overlap with genes implicated in energy metabolism phenotypes, plausibly reflecting adaptations to novel dietary sources available in the Americas

Identification of KIF3A as a Novel Candidate Gene for Childhood Asthma Using RNA Expression and Population Allelic Frequencies Differences

Asthma is a chronic inflammatory disease with a strong genetic predisposition. A major challenge for candidate gene association studies in asthma is the selection of biologically relevant genes.Using epithelial RNA expression arrays, HapMap allele frequency variation, and the literature, we identified six possible candidate susceptibility genes for childhood asthma including ADCY2, DNAH5, KIF3A, PDE4B, PLAU, SPRR2B. To evaluate these genes, we compared the genotypes of 194 predominantly tagging SNPs in 790 asthmatic, allergic and non-allergic children. We found that SNPs in all six genes were nominally associated with asthma (p<0.05) in our discovery cohort and in three independent cohorts at either the SNP or gene level (p<0.05). Further, we determined that our selection approach was superior to random selection of genes either differentially expressed in asthmatics compared to controls (p = 0.0049) or selected based on the literature alone (p = 0.0049), substantiating the validity of our gene selection approach. Importantly, we observed that 7 of 9 SNPs in the KIF3A gene more than doubled the odds of asthma (OR = 2.3, p<0.0001) and increased the odds of allergic disease (OR = 1.8, p<0.008). Our data indicate that KIF3A rs7737031 (T-allele) has an asthma population attributable risk of 18.5%. The association between KIF3A rs7737031 and asthma was validated in 3 independent populations, further substantiating the validity of our gene selection approach.Our study demonstrates that KIF3A, a member of the kinesin superfamily of microtubule associated motors that are important in the transport of protein complexes within cilia, is a novel candidate gene for childhood asthma. Polymorphisms in KIF3A may in part be responsible for poor mucus and/or allergen clearance from the airways. Furthermore, our study provides a promising framework for the identification and evaluation of novel candidate susceptibility genes

Latin Americans show wide-spread Converso ancestry and imprint of local Native ancestry on physical appearance

Historical records and genetic analyses indicate that Latin Americans trace their ancestry mainly to the intermixing (admixture) of Native Americans, Europeans and Sub-Saharan Africans. Using novel haplotype-based methods, here we infer sub-continental ancestry in over 6,500 Latin Americans and evaluate the impact of regional ancestry variation on physical appearance. We find that Native American ancestry components in Latin Americans correspond geographically to the present-day genetic structure of Native groups, and that sources of non-Native ancestry, and admixture timings, match documented migratory flows. We also detect South/East Mediterranean ancestry across Latin America, probably stemming mostly from the clandestine colonial migration of Christian converts of non-European origin (Conversos). Furthermore, we find that ancestry related to highland (Central Andean) versus lowland (Mapuche) Natives is associated with variation in facial features, particularly nose morphology, and detect significant differences in allele frequencies between these groups at loci previously associated with nose morphology in this sample.Instituto Multidisciplinario de Biología Celula

Latin Americans show wide-spread Converso ancestry and imprint of local Native ancestry on physical appearance

Historical records and genetic analyses indicate that Latin Americans trace their ancestry mainly to the intermixing (admixture) of Native Americans, Europeans and Sub-Saharan Africans. Using novel haplotype-based methods, here we infer sub-continental ancestry in over 6,500 Latin Americans and evaluate the impact of regional ancestry variation on physical appearance. We find that Native American ancestry components in Latin Americans correspond geographically to the present-day genetic structure of Native groups, and that sources of non-Native ancestry, and admixture timings, match documented migratory flows. We also detect South/East Mediterranean ancestry across Latin America, probably stemming mostly from the clandestine colonial migration of Christian converts of non-European origin (Conversos). Furthermore, we find that ancestry related to highland (Central Andean) versus lowland (Mapuche) Natives is associated with variation in facial features, particularly nose morphology, and detect significant differences in allele frequencies between these groups at loci previously associated with nose morphology in this sample.Instituto Multidisciplinario de Biología Celula

Enfermedades crónicas

Adherencia al tratamiento farmacol&oacute;gico y relaci&oacute;n con el control metab&oacute;lico en pacientes con DM2Aluminio en pacientes con terapia de reemplazo renal cr&oacute;nico con hemodi&aacute;lisis en Bogot&aacute;, ColombiaAmputaci&oacute;n de extremidades inferiores: &iquest;est&aacute;n aumentando las tasas?Consumo de edulcorantes artificiales en j&oacute;venes universitariosC&oacute;mo crecen ni&ntilde;os normales de 2 a&ntilde;os que son sobrepeso a los 7 a&ntilde;osDiagn&oacute;stico con enfoque territorial de salud cardiovascular en la Regi&oacute;n MetropolitanaEfecto a corto plazo de una intervenci&oacute;n con ejercicio f&iacute;sico, en ni&ntilde;os con sobrepesoEfectos de la cirug&iacute;a bari&aacute;trica en pacientes con s&iacute;ndrome metab&oacute;lico e IMC &lt; 35 KG/M2Encuesta mundial de tabaquismo en estudiantes de profesiones de saludEnfermedades cr&oacute;nicas no transmisibles: Consecuencias sociales-sanitarias de comunidades rurales en ChileEpidemiolog&iacute;a de las muertes hospitalarias por patolog&iacute;as relacionadas a muerte encef&aacute;lica, Chile 2003-2007Estado nutricional y conductas alimentarias en adolescentes de 4&ordm; medio de la Regi&oacute;n de CoquimboEstudio de calidad de vida en una muestra del plan piloto para hepatitis CEvaluaci&oacute;n del proceso asistencial y de resultados de salud del GES de diabetes mellitus 2Factores de riesgo cardiovascular en poblaci&oacute;n universitaria de la Facsal, universidad de Tarapac&aacute;Implicancias psicosociales en la g&eacute;nesis, evoluci&oacute;n y tratamiento de pacientes con hipertensi&oacute;n arterial esencialInfarto agudo al miocardio (IAM): Realidad en el Hospital de Puerto Natales, 2009-2010Introducci&oacute;n de nuevas TIC y mejor&iacute;a de la asistencia a un programa de saludNi&ntilde;os obesos atendidos en el Cesfam de Puerto Natales y su entorno familiarPerfil de la mortalidad por c&aacute;ncer de cuello uterino en R&iacute;o de JaneiroPerfil del paciente primo-consultante del Programa de Salud Cardiovascular, Consultorio Cordillera Andina, Los AndesPrevalencia de automedicaci&oacute;n en mujeres beneficiarias del Hospital Comunitario de Til-TiPrevalencia de caries en poblaci&oacute;n preescolar y su relaci&oacute;n con malnutrici&oacute;n por excesoPrevalencia de retinopat&iacute;a diab&eacute;tica en comunas dependientes del Servicio de Salud Metropolitano Occidente (SSMOC)Problemas de adherencia farmacol&oacute;gica antihipertensiva en poblaci&oacute;n mapuche: Un estudio cualitativoRol biol&oacute;gico de los antioxidantes innatos en pacientes portadores de VIH/SidaSobrepeso en empleados de un restaurante de una universidad p&uacute;blica del estado de S&atilde;o Paul

Disentangling Signatures of Selection Before and After European Colonization in Latin Americans

Throughout human evolutionary history, large-scale migrations have led to intermixing (i.e., admixture) between previously separated human groups. Although classical and recent work have shown that studying admixture can yield novel historical insights, the extent to which this process contributed to adaptation remains underexplored. Here, we introduce a novel statistical model, specific to admixed populations, that identifies loci under selection while determining whether the selection likely occurred post-admixture or prior to admixture in one of the ancestral source populations. Through extensive simulations, we show that this method is able to detect selection, even in recently formed admixed populations, and to accurately differentiate between selection occurring in the ancestral or admixed population. We apply this method to genome-wide SNP data of ∼4,000 individuals in five admixed Latin American cohorts from Brazil, Chile, Colombia, Mexico, and Peru. Our approach replicates previous reports of selection in the human leukocyte antigen region that are consistent with selection post-admixture. We also report novel signals of selection in genomic regions spanning 47 genes, reinforcing many of these signals with an alternative, commonly used local-ancestry-inference approach. These signals include several genes involved in immunity, which may reflect responses to endemic pathogens of the Americas and to the challenge of infectious disease brought by European contact. In addition, some of the strongest signals inferred to be under selection in the Native American ancestral groups of modern Latin Americans overlap with genes implicated in energy metabolism phenotypes, plausibly reflecting adaptations to novel dietary sources available in the Americas