Curvas de crecimiento en bovinos Limousin de raza pura y cruzados

The objective was to fit a non-linear model (NLM) to evaluate the growth curve in purebred (PB) Limousin cattle and in five degrees of crossbreeding (DCBs: 1/2, 3/4, 7/8, 15/16, 31/32 Limousin). Live weight, the birth weight interval at 500 d of age, was analyzed. Four NLMs were evaluated: Brody, Bertalanffy, Gompertz, and logistic. Growth parameters were estimated: adult weight (ADW); growth rate (GR); age (AIP; months) and weight (WIP; kg) at inflection point; age (months; A50M) to reach 50 % maturity and degree of maturity at 15 mo (DM15). The growth curve in DCB was characterized using the NLM selected for BP. The best-fitting model was Bertalanffy. The ADW for purebred (PB) males was 566.1, for crossbred (CB) males it was in the range of 446.9 to 527.4; for CB females it was in the range of 374.5 to 419.9, and for PB females, it was 443.0. The NLMs exhibited correlations below -0.75 between ADW and GR. In PB heifers, AIP was estimated at 3.7, and WIP, at 131.2; in CB heifers, AIP and WIP were in the ranges of 2.9 to 3.7 and 110.9 to 124.4, respectively. A50M for PB females was 10.6, and for CB females, within the range of 8.9 to 10.5. DM15 for CB females, the average was 90.5 %, and 87.9 % for PB females. PB males reach A50M at the age of 13 mo.El objetivo fue el ajuste de un modelo no lineal (MNL) para evaluar la curva de crecimiento en bovinos Limousin, en pureza de raza (PRZ) y cinco grados de cruzamiento (GPZ; 1/2, 3/4, 7/8, 15/16, 31/32 de Limousin). Se analizó el peso vivo, el intervalo de peso al nacer a 500 días de edad. Se evaluaron cuatro MNL: Brody, Bertalanffy, Gompertz y logístico. Se estimaron parámetros de crecimiento: peso adulto (PAD); tasa de crecimiento (TAC); edad (EPI; meses) y peso (PPI; kg) al punto de inflexión; edad (meses; E50M) para alcanzar 50% de madurez y madurez a 15 meses (GM15). Con el MNL seleccionado en PRZ se caracterizó la curva de crecimiento en GPZ. El modelo de mejor ajuste fue Bertalanffy. El PAD para machos PRZ fue 566.1, para GPZ estuvo en el intervalo de 446.9 a 527.4; para hembras, en GPZ estuvo en el intervalo de 374.5 a 419.9, en PRZ fue 443.0. Los MNL presentaron correlaciones por debajo de -0.75 entre PAD y TAC. En vaquillas de PRZ, EPI se estimó a 3.7 con 131.2 para PPI; en GPZ, EPI y PPI estuvieron en los intervalos de 2.9 a 3.7 y 110.9 a 124.4, respectivamente. E50M para hembras, en PRZ fue a 10.6 y para GPZ en el intervalo de 8.9 a 10.5. GM15 para hembras, en GPZ el promedio fue 90.5 % en PRZ fue de 87.9 %. Los machos en PRZ alcanzan E50M a partir de 13 meses

Estructura y variabilidad genética del bisonte americano (Bison bison) en México

Controlling for genetic variables to managing conservation populations. Single nucleotide polymorphism (SNP) genetic markers were used to analyze genetic structure and variability in an American bison population in the state of Chihuahua, Mexico. A total of 174 individuals were sampled and analysis done of 42,366 SNP distributed in 29 chromosomes. Estimates were done of expected (He) and observed (Ho) heterozygosity, polymorphic information content (PIC), the fixation index (FST), the Shannon index (SI), linkage disequilibrium (LD), kinship relationships (Rij; %), and effective population size (Ne). A genetic structure analysis was run to infer how many lines or genomes (k) define the studied population. A panel with 2,135 polymorphic SNPs was identified and selected, with an average of 74 SNP per chromosome. In the exclusion process, 84.5 % were monomorphic, 8.5 % had a usable percentage less than 90 %, 6.3 % had a minor allele frequency less than 0.01 and 0.70 % exhibited Hardy-Weinberg disequilibrium (P<0.05). Estimated values were 0.30 for the SI, 0.187 for Ho, 0.182 for He, -0.029 for the FST, and 0.152 for PIC. Of the 15,051 Rij estimates generated, the average value was 7.6 %, and 45.1 % were equal to zero. The Ne was 12.5, indicating a possible increase of 4 % in consanguinity per generation. Three genetic lines were identified (proportions = 0.730, 0.157 and 0.113), and, given the study population’s origin, are probably associated with natural selection or genetic drift. Genetic variability, as well as Rij levels, must be considered in conservation schemes.Los objetivos fueron analizar la estructura y variabilidad genética del bisonte americano con marcadores genéticos de tipo SNP. Se muestrearon 174 bisontes y se analizaron 42,366 SNP distribuidos en los 29 cromosomas. Se estimó la heterocigosis esperada (He) y observada (Ho), contenido de información polimórfica (CIP), índice de fijación (FIS), índice de Shannon (IS), desequilibrio de ligamiento y relación de parentesco (Rij; %), así como el tamaño efectivo de población (Ne). Se realizó un análisis de estructura genética para inferir cuántas líneas o genomas (k) definen la población. Se identificó y seleccionó un panel con 2,135 SNP polimórficos, con un promedio de 74 SNP por cromosoma. En el proceso de exclusión,  84.5 % fueron monomórficos,  8.5 % con porcentaje de usables menor a 90 %, 6.3 % con frecuencia del alelo menor inferior a 0.01 y 0.70 % por desequilibrio Hardy-Weinberg (P<0.05). Las estimaciones de IS, Ho, He, FIS y CIP fueron de 0.30, 0.187, 0.182, -0.029 y 0.152, respectivamente. Se generaron 15,051 estimaciones de Rij, el valor promedio de éstas fue 7.6 %, y el 45.1 % de ellas fue igual a cero. El Ne fue de 12.5, señalando un posible incremento de consanguinidad por generación de 4 %. Se identificaron tres líneas genéticas, con proporciones de 0.730, 0.157 y 0.113; dado el origen de la población, se asocian a selección natural o deriva genética. La variabilidad genética, así como los niveles de la Rij, se deben de considerar en esquemas de conservación

Diversidad genética en burros criollos de México

The aim of this study was to evaluate the genetic diversity of the Mexican criollo donkey with SNP-type genetic markers. Sixteen individuals (eight males and eight females) were randomly sampled and genotyped using the GGP Equine 70K chip (71 947 loci). Within chromosome the polymorphic SNPs were identified, determining the expected (He) and observed (Ho) heterozygosity, polymorphic information content (PIC), the fixation index (FIS) and the Hardy-Weinberg equilibrium (HW). Linkage disequilibrium was assessed based on the correlation (r2) between frequencies across loci. An analysis of molecular variance (AMOVA) and a cluster study were performed to infer the number of clusters (k). It was found that 3579 loci (4.9%) presented genetic variability, but 24.9% presented HW disequilibrium (p&lt;0.05). Across chromosomes, the number of polymorphic loci ranged from 50 to 269 with a mean of 115. The (within chromosome) means for PIC and FIS ranged from 0.222 to 0.267 and -0.392 to -0.208, respectively. In all chromosomes Ho was superior to He. For r2, the mean values within chromosome were greater than 0.10; the optimal k corresponded to 2. In the AMOVA, the genetic variability within individuals explained 67%. The SNPs identified as polymorphic make up a first panel of genetic markers for the Mexican creole burro, and the estimated genetic variability can be used in development and conservation schemes.El estudio tuvo como objetivo evaluar la diversidad genética del burro criollo mexicano con marcadores genéticos de tipo SNP. Se muestreó aleatoriamente a 16 individuos (ocho machos y ocho hembras) y el genotipado se hizo con el chip GGP Equine 70K (71 947 loci). Dentro de cromosoma se identificaron los SNP polimórficos, determinándose la heterocigosis esperada (He) y observada (Ho), contenido de información polimórfica (CIP), el índice de fijación (FIS) y el equilibrio (HW) Hardy-Weinberg. El desequilibrio de ligamiento se evaluó con base en la correlación (r2) entre frecuencias a través de locus. Se realizó un análisis de varianza molecular (AMOVA) y un estudio de agrupamiento para inferir el número de cluster (k). Se encontró que 3579 loci (4.9%) presentaron variabilidad genética, pero el 24.9% presentó desequilibrio HW (p&lt;0.05). A través de cromosomas, el número de loci polimórficos osciló de 50 a 269 con un promedio de 115. Los promedios (dentro de cromosoma) para PIC y FIS fluctuaron de 0.222 a 0.267 y de -0.392 a -0.208, respectivamente. En todos los cromosomas Ho fue superior a He. Para r2, los valores promedio dentro de cromosoma fueron superior a 0.10; el k óptimo correspondió a 2. En el AMOVA, la variabilidad genética dentro de individuos explicó el 67%. Los SNP identificados como polimórficos, conforman un primer panel de marcadores genéticos para el burro criollo mexicano, y la variabilidad genética estimada puede ser utilizada en esquemas de desarrollo y conservación

Características epidemiológicas de receptores de trasplante cardiaco en el Perú, 2010-2020

Objective. To evaluate the epidemiological, clinical, surgical, pathological characteristics and outcomes in the follow-up of heart transplant recipients at the National Cardiovascular Institute during 2010-2020. Material and methods. A retrospective descriptive study was performed by reviewing the medical records of patients undergoing heart transplantation at a national referral center, describing the clinical, surgical, laboratory, pathology characteristics and survival of patients up to 10 years of follow-up. Results. Eightysix patients were transplanted in 10 years, the median age was 41 years (RIQ 28-56), being predominantly male (66.3%). The three leading causes of indication for heart transplantation were: dilated cardiomyopathy (48.9%), ischemic heart disease (17.4%), and myocarditis (6.9%). Total ischemia time was 160 minutes (RIQ 129.7-233.5). Survival at one, five, and ten years was 84.8%, 73.6%, and 65.7% respectively. The main cause of death was non-cardiac: infectious (39.1%) and of unknown origin (26%). Conclusions. The main etiology of heart failure in heart transplant recipients in Peru in recent years was nonischemic dilated cardiomyopathy. We observed that the survival rate was similar to that of international registries; however, the rate of mortality due to infectious causes and death of unknown origin is high, which poses a challenge in the management of post-transplant patients.Objetivo. Evaluar las características epidemiológicas, clínicas, quirúrgicas, patológicas y desenlaces en el seguimiento de los pacientes receptores de trasplante cardiaco en el Instituto Nacional Cardiovascular durante 2010-2020. Materiales y métodos. Estudio retrospectivo descriptivo de pacientes sometidos a trasplante cardiaco en un centro de referencia nacional, se describen las características clínicas, quirúrgicas, de laboratorio, de patología y la supervivencia de los pacientes hasta los 10 años de seguimiento. Resultados. Ochenta y seis pacientes fueron trasplantados en 10 años, la mediana de edad fue de 41 años (RIQ 28-56), con predominancia de varones (66,3%). Las tres primeras causas de indicación de trasplante cardiaco fueron: cardiomiopatía dilatada (48,9%), cardiopatía isquémica (17,4%) y miocarditis (6,9%). El tiempo de isquemia total fue de 160 min (RIQ 129,7-233,5). La sobrevida al año, cinco y diez años fue de 84,8%, 73,6% y 65,7%, respectivamente. La principal causa de muerte fue la infecciosa (39,1%) y de origen desconocido (26%). Conclusiones. La principal etiología de la insuficiencia cardiaca en el receptor de trasplante cardiaco en el Perú, en los últimos años, fue la cardiomiopatía dilatada no isquémica. Se observa que la tasa de sobrevida fue similar a la de registros internacionales; sin embargo, la tasa de mortalidad de causa infecciosa y muerte de origen desconocido es alta, lo cual plantea un desafío en el manejo de los pacientes postrasplante

Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO

Jet energy measurement with the ATLAS detector in proton-proton collisions at root s=7 TeV

The jet energy scale and its systematic uncertainty are determined for jets measured with the ATLAS detector at the LHC in proton-proton collision data at a centre-of-mass energy of √s = 7TeV corresponding to an integrated luminosity of 38 pb-1. Jets are reconstructed with the anti-kt algorithm with distance parameters R=0. 4 or R=0. 6. Jet energy and angle corrections are determined from Monte Carlo simulations to calibrate jets with transverse momenta pT≥20 GeV and pseudorapidities {pipe}η{pipe}<4. 5. The jet energy systematic uncertainty is estimated using the single isolated hadron response measured in situ and in test-beams, exploiting the transverse momentum balance between central and forward jets in events with dijet topologies and studying systematic variations in Monte Carlo simulations. The jet energy uncertainty is less than 2. 5 % in the central calorimeter region ({pipe}η{pipe}<0. 8) for jets with 60≤pT<800 GeV, and is maximally 14 % for pT<30 GeV in the most forward region 3. 2≤{pipe}η{pipe}<4. 5. The jet energy is validated for jet transverse momenta up to 1 TeV to the level of a few percent using several in situ techniques by comparing a well-known reference such as the recoiling photon pT, the sum of the transverse momenta of tracks associated to the jet, or a system of low-pT jets recoiling against a high-pT jet. More sophisticated jet calibration schemes are presented based on calorimeter cell energy density weighting or hadronic properties of jets, aiming for an improved jet energy resolution and a reduced flavour dependence of the jet response. The systematic uncertainty of the jet energy determined from a combination of in situ techniques is consistent with the one derived from single hadron response measurements over a wide kinematic range. The nominal corrections and uncertainties are derived for isolated jets in an inclusive sample of high-pT jets. Special cases such as event topologies with close-by jets, or selections of samples with an enhanced content of jets originating from light quarks, heavy quarks or gluons are also discussed and the corresponding uncertainties are determined. © 2013 CERN for the benefit of the ATLAS collaboration

Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

The inclusive and dijet production cross-sections have been measured for jets containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The measurements use data corresponding to an integrated luminosity of 34 pb^-1. The b-jets are identified using either a lifetime-based method, where secondary decay vertices of b-hadrons in jets are reconstructed using information from the tracking detectors, or a muon-based method where the presence of a muon is used to identify semileptonic decays of b-hadrons inside jets. The inclusive b-jet cross-section is measured as a function of transverse momentum in the range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet cross-section is measured as a function of the dijet invariant mass in the range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets and the angular variable chi in two dijet mass regions. The results are compared with next-to-leading-order QCD predictions. Good agreement is observed between the measured cross-sections and the predictions obtained using POWHEG + Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet cross-section. However, it does not reproduce the measured inclusive cross-section well, particularly for central b-jets with large transverse momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final version published in European Physical Journal

Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO

Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC

The uncertainty on the calorimeter energy response to jets of particles is derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the calorimeter response to single isolated charged hadrons is measured and compared to the Monte Carlo simulation using proton-proton collisions at centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009 and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter response to specific types of particles (positively and negatively charged pions, protons, and anti-protons) is measured and compared to the Monte Carlo predictions. Finally, the jet energy scale uncertainty is determined by propagating the response uncertainty for single charged and neutral particles to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3% for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table, submitted to European Physical Journal

Observation of associated near-side and away-side long-range correlations in √sNN=5.02 TeV proton-lead collisions with the ATLAS detector

Two-particle correlations in relative azimuthal angle (Δϕ) and pseudorapidity (Δη) are measured in √sNN=5.02  TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1  μb-1 of data as a function of transverse momentum (pT) and the transverse energy (ΣETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Δη|<5) “near-side” (Δϕ∼0) correlation that grows rapidly with increasing ΣETPb. A long-range “away-side” (Δϕ∼π) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ΣETPb, is found to match the near-side correlation in magnitude, shape (in Δη and Δϕ) and ΣETPb dependence. The resultant Δϕ correlation is approximately symmetric about π/2, and is consistent with a dominant cos⁡2Δϕ modulation for all ΣETPb ranges and particle pT