25 results on '"Arango J"'
Search Results
2. Accuracy of genomic prediction of shell quality in a White Leghorn line
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Wolc, A., Drobik-Czwarno, W., Jankowski, T., Arango, J., Settar, P., Fulton, J.E., Fernando, R.L., Garrick, D.J., and Dekkers, J.C.M.
- Abstract
Several genomic methods were applied for predicting shell quality traits recorded at 4 different hen ages in a White Leghorn line. The accuracies of genomic prediction of single-step GBLUP and single-trait Bayes B were compared with predictions of breeding values based on pedigree-BLUP under single-trait or multitrait models. Breaking strength (BS) and dynamic stiffness (Kdyn) measurements were collected on 18,524 birds from 3 consecutive generations, of which 4,164 animals also had genotypes from an Affymetrix 50K panel containing 49,591 SNPs after quality control edits. All traits had low to moderate heritability, ranging from 0.17 for BS to 0.34 for Kdyn. The highest accuracies of prediction were obtained for the multitrait single-step model. The use of marker information resulted in higher prediction accuracies than pedigree-based models for almost all traits. A genome-wide association study based on a Bayes B model was conducted to detect regions explaining the largest proportion of genetic variance. Across all 8 shell quality traits analyzed, 7 regions each explaining over 2% of genetic variance and 54 regions each explaining over 1% of genetic variance were identified. The windows explaining a large proportion of genetic variance overlapped with several potential candidate genes with biological functions linked to shell formation. A multitrait repeatability model using a single-step method is recommended for genomic evaluation of shell quality in layer chickens.
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- 2020
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3. Manejo diagnóstico-terapéutico de las lesiones mamarias atípicas
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Delgado Márquez, M. and Rodríguez Arango, J.
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- 2018
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4. Repeatability vs. multiple-trait models to evaluate shell dynamic stiffness for layer chickens
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Wolc, A., Arango, J., Settar, P., O'Sullivan, N. P., and Dekkers, J. C. M.
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Shell quality is one of the most important traits for improvement in layer chickens. Proper consideration of repeated records can increase the accuracy of estimated breeding values and thus genetic improvement of shell quality. The objective of this study was to compare different models for genetic evaluation of the collected data. For this study, 81,646 dynamic stiffness records on 21,321 brown egg layers and 93,748 records on 24,678 white egg layers from 4 generations were analyzed. Across generations, data were collected at 2 to 4 ages (at approximately 26, 42, 65, and 86 wk), with repeated records at each age. Seven models were compared, including 5 repeatability models with increasing complexity, a random regression model, and a multitrait model. The models were compared using Akaike Information Criteria with significance testing of nested models with a Log Likelihood Ratio test. Estimates of heritability were 0.31–0.36 for the brown line and 0.23–0.26 for the white line, but repeatability was higher for the model with age-specific permanent environment effects (0.59 for both lines) than for the model with an overall permanent environmental effects (0.47 for the brown and 0.41 for the white line). The model that allowed for permanent environmental effect within age and heterogeneous residual variance between ages resulted in improved fit compared to the traditional model that fits single permanent environment and residual effects, but was inferior in fit and predictive ability to the full multiple-trait model. The random regression model had better fit to the data than repeatability models but slightly worse than the multiple-trait model. For traits with repeated records at different ages, repeatability within and across ages as well as genetic correlations should be considered while choosing the number of records collected per individual as well as the model for genetic evaluation.
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- 2017
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5. Poultry industry paradigms: connecting the dots
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Castro, F.L.S., Chai, L., Arango, J., Owens, C.M., Smith, P.A., Reichelt, S., DuBois, C., and Menconi, A.
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Providing high-quality food for the increasing world population with limited natural resources is a challenge for animal agriculture. Over the past decades, poultry production has undergone remarkable advancements to adapt to emerging challenges and evolving changes in consumer expectations. Among these changes, the need for an animal protein production system that considers the social, economic, and environmental aspects of sustainability has increased. With that in mind, efforts were and will continue to be made toward improving various aspects of the poultry production chain. Genetic selection has evolved from a simple phenotypic mass selection to the use of genomics, focusing not only on efficiency, but also on animal welfare and the demand from niche markets. Precision poultry farming technologies should be further innovated to develop the core component of an integrated imaging system for evaluating poultry production and wellbeing. Moreover, feed formulation will continue to be adjusted as the birds' nutritional requirements, feed ingredient availability, and cost change, and bird processing will continue to adopt technologies that can improve meat quality and reduce labor intensity and demand. These adaptations highlight a dynamic aspect of the poultry industry and its continuous effort to produce a safe, cost-effective, and environment friendly protein source while maintaining animal welfare.
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- 2023
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6. Mechanical Strain in Capped and Uncapped Self-Assembled Ge/Si Quantum Dots
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Gomes, P., Fernandes, H., and González-Arango, J.
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In this study, we numerically calculate the spatial profile of mechanical strain on self-assembled germanium (Ge) quantum dots (QDs) grown on a silicon (Si) substrate. Although the topic has been exhaustively studied, interesting features have not been explained or even mentioned in the literature yet. We studied the effect of the cap layer considering two cases: capped QDs (where a Si cap is present above the Ge QDs) and uncapped QDs (where no Si is present above the Ge QDs). We observed that Ge in the capped QDs is more strained compared with the uncapped QDs. This expected effect is attributed to the additional tension from the Si cap layer. However, the situation is opposite for the Si substrate, it is more strained in the uncapped QD because the Ge layer is less strained in this case. We also calculated the band-edge alignment for the electrons and holes.
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- 2015
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7. MA10.08 Activated Pathways of Myastenia Gravis in Thymic Epithelial (TETs)
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Benítez, J.C., JOB, B., Thomas de Montpréville, V., Lacroix, L., Saulnier, P., Arana, R., Lambotte, O., Mussot, S., Mercier, O., Fadel, E., Florez-Arango, J., Scoazec, J.-Y., Molina, T., and Besse, B.
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- 2022
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8. Segmentation of prostate from CT scans using a combined voxel random forests classification with spherical harmonics regularization
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Romero, Eduardo, Lepore, Natasha, Commandeur, F., Acosta, O., Simon, A., Ospina Arango, J. D., Dillenseger, J. L., Mathieu, R., Haigron, P., and de Crevoisier, R.
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- 2015
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9. Study of codes of disposal at different parities of Large White sows using a linear censored model
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Arango, J., Misztal, I., Tsuruta, S., Culbertson, M., and Herring, W.
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To study the genetic relationship between three grouped reasons for sow removal (SR) in consecutive parities, accounting for censoring, 13,838 records from Large White sows were analyzed. Data were from seven pure-line farms having, on average, 5.9% unknown SR. Three traits were subjectively defined, each corresponding to a classification of SR (reproductive [RR], nonreproductive [RN], and others [RO]). Records for each trait could take one of five categories, according to parity at removal (0 to 4 or later). A multivariate linear censored model was implemented. The model to estimate (co)variance components and parameters included the effects of year-season, region, contemporary group, and additive genetic effects. The most common SR was related to reproduction (48.5%). Diseases of different origin and cause, old age/parity, and sow death or loss accounted for about 18, 7, and 4% of total culls, respectively. Estimates of variance components showed heterogeneity of additive genetic and residual variances for the three traits. Estimates of heritability were 0.18, 0.13, and 0.15 for RR, RN, and RO, respectively. Genetic correlations between removal codes were high (≥0.90). Results suggest sizeable additive genetic variances exist for parity at removal and different codes of removal. Different SR reasons seem to operate similarly or as a closely related genetic trait associated with fitness. In particular, RN and RO seem to be genetically indistinguishable. Data structure, definition, and volume are major limitations in studies of sow survival. A multiple-trait censored model is preferred to evaluate reasons of sow disposal. Grouped removal causes seem to be strongly genetically correlated but with heterogeneous variances, suggesting that combining all removal causes and treating the trait as parity at disposal is an alternative approach.
- Published
- 2005
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10. Estimation of variance components including competitive effects of Large White growing gilts1
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Arango, J., Misztal, I., Tsuruta, S., Culbertson, M., and Herring, W.
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Records of on-test ADG of Large White gilts were analyzed to estimate variance components of direct and associative genetic effects. Models included the effects of contemporary group (farm-barn-batch), birth litter, pen group, and direct and associative additive genetic effects. The area of each pen was 14 m2. The additive genetic variance was a function of the number of competitors in a group, the additive relationships between the animal performing the record and its pen mates, and the additive relationships between pen mates. To partially account for differences in the number of pen mates, a covariable (qi= 1, 1/n, or 1/n½) was added to the associative genetic effect. There were 4,946 records from 2,409 litters and 362 pen groups. Pen group size ranged from 12 to 16 gilts. Analyses by REML converged very slowly. A grid search showed that the likelihood function was almost flat when the additive genetic associative effect was fitted. Estimates of direct and associative heritability were 0.15 and 0.03, respectively. Within the BLUPF90 family of programs, the mixed-model equations can be set up directly. For variance component estimation, simple programs (REMLF90 and GIBBSF90) worked without modifications, but more optimized programs did not. Estimates obtained using the three values of qiwere similar. With the data structure available for this study and under an environment with relative low competition among animals, accurate estimation of associative genetic effects was not possible. Estimation of competitive effects with large pen size is difficult. The magnitude of competition effects may be larger in commercial populations, where housing is denser and food is limited.
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- 2005
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11. Threshold-linear estimation of genetic parameters for farrowing mortality, litter size, and test performance of Large White sows
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Arango, J., Misztal, I., Tsuruta, S., Culbertson, M., and Herring, W.
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Up to 109,447 records of 49,656 Large White sows were used to evaluate the genetic relationship between number of pigs born dead (BD) and number born alive (BA) in first and later parities. Performance data (n = 30,832) for ultrasound backfat (BF) at the end of the test and days to reach 113.5 kg (AD) were used to estimate their relationships with BD and BA at first parity in a four-trait threshold-linear analysis (TL). Effects were year-farm, contemporary group (CG: farm-farrowing year-farrowing month) and animal additive genetic. At first parity, estimates of heritability were 0.09, 0.09, 0.37, and 0.31 for BA, BD, AD, and BF, respectively. The estimate of genetic correlation between BD and litter size was −0.04 (BD-BA). Corresponding values with test traits were both −0.14 (BD-AD, BD-BF). Estimates of genetic correlation between BA and performance traits were 0.08 (BA-AD) and 0.05 (BA-BF). The two test traits were moderately negatively correlated (−0.22). For later parities, a six-trait (BD, BA in three parities) TL model was implemented. The estimates of additive genetic variances and heritability increased with parity for BD and BA. Estimates of heritabilities were: 0.09, 0.10, and 0.11 for BD, and 0.09, 0.12, and 0.12 for BA in parities one to three, respectively. Estimates of genetic correlations between different parities were high (0.91 to 0.96) for BD, and slightly lower (0.74 to 0.95) for BA. Genetic correlations between BD and BA were low and positive (0.02 to 0.17) for BA in Parities 1 and 2, but negative (−0.04 to −0.10) for BA in Parity 3. Selection for increased litter size should have little effect on farrowing piglet mortality. Intense selection for faster growth and increased leanness should increase farrowing piglet mortality of first-parity sows. A repeatability model with a simple correction for the heterogeneity of variances over parities could be implemented to select against farrowing mortality. The genetic components of perinatal piglet mortality are independent of the ones for litter size in the first parity, and they show an undesirable, but not strong, genetic association in second parity.
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- 2005
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12. Comparisons of Angus, Charolais, Galloway, Hereford, Longhorn, Nellore, Piedmontese, Salers, and Shorthorn breeds for weight, weight adjusted for condition score, height, and condition score of cows1
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Arango, J. A., Cundiff, L. V., and Van Vleck, L. D.
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Breed differences for weight (CW), height (CH), and condition score (CS) were estimated from records (n = 12,188) of 2- to 6-yr-old cows (n = 744) from Cycle IV of the U.S. Meat Animal Research Center's Germplasm Evaluation (GPE) Program. Cows were produced from mating Angus and Hereford dams to Angus, Hereford, Charolais, Shorthorn, Galloway, Longhorn, Nellore, Piedmontese, and Salers sires. Samples of Angus and Hereford sires were 1) reference sires born from 1962 through 1970 and 2) 1980s sires born in 1980 through 1987. The mixed model included cow age, season of measurement and their interactions, year of birth, pregnancy-lactation code (PL), and breed-group as fixed effects for CW and CS. Analyses of weight adjusted for condition score included CS as a linear covariate. The model for CH excluded PL. Random effects were additive genetic and permanent environmental effects associated with the cow. Differences among breed groups were significant (P< 0.05) for all traits and were maintained through maturity with few interchanges in ranking. The order of F1cows for weight was as follows: Charolais (506 to 635 kg for different ages), Shorthorn and Salers, reciprocal Hereford-Angus (HA) with 1980s sires, Nellore, HA with reference sires, Galloway, Piedmontese, and Longhorn (412 to 525 kg for different ages). Order for height was as follows: Nellore (136 to 140 cm), Charolais, Shorthorn, Salers, HA with 1980s sires, Piedmontese, Longhorn, Galloway and HA with reference sires (126 to 128 cm). Hereford and Angus cows with reference sires were generally lighter than those with 1980s sires. In general, breed differences for height followed those for weight except that F1Nellore cows were tallest, which may in part be due to Bos taurus-Bos indicusheterosis for size.
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- 2004
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13. Covariance functions and random regression models for cow weight in beef cattle1
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Arango, J. A., Cundiff, L. V., and Van Vleck, L. D.
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Data from the first four cycles of the Germplasm Evaluation program at the U.S. Meat Animal Research Center were used to evaluate weights of Angus, Hereford, and F1cows produced by crosses of 22 sire and 2 dam (Angus and Hereford) breeds. Four weights per year were available for cows from 2 through 8 yr of age (AY) with age in months (AM). Weights (n = 61,798) were analyzed with REML using covariance function-random regression models (CF-RRM), with regression on orthogonal (Legendre) polynomials of AM. Models included fixed regression on AM and effects of cow line, age in years, season of measurement, and their interactions; year of birth; and pregnancy-lactation codes. Random parts of the models fitted RRM coefficients for additive (a) and permanent environmental (c) effects. Estimates of CF were used to estimate covariances among all ages. Temporary environmental effects were modeled to account for heterogeneity of variance by AY. Quadratic fixed regression was sufficient to model population trajectory and was fitted in all analyses. Other models varied order of fit and rank of coefficients for a and c. A parsimonious model included linear and quartic regression coefficients for a and c, respectively. A reduced cubic order sufficed for c. Estimates of all variances increased with age. Estimates for older ages disagreed with estimates using traditional bivariate models. Plots of covariances for c were smooth for intermediate, but erratic for extreme ages. Heritability estimates ranged from 0.38 (36 mo) to 0.78 (94 mo), with fluctuations especially for extreme ages. Estimates of genetic correlations were high for most pairs of ages, with the lowest estimate (0.70) between extreme ages (19 and 103 mo). Results suggest that although cow weights do not fit a repeatability model with constant variances as well as CF-RRM, a repeatability model might be an acceptable approximation for prediction of additive genetic effects.
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- 2004
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14. Breed comparisons of Angus, Brahman, Hereford, Pinzgauer, Sahiwal, and Tarentaise for weight, weight adjusted for condition score, height, and body condition score1
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Arango, J. A., Cundiff, L. V., and Van Vleck, L. D.
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Data from topcross cows (n = 468) from six breeds of sire (Angus, Brahman, Hereford, Pinzgauer, Sahiwal, Tarentaise) and two breeds of dam (Angus and Hereford) of Cycle III of the Germplasm Evaluation (GPE) program at the U.S. Meat Animal Research Center (MARC) comprising cow weight (CW, n = 9,012), height (CH, n = 9,010), and condition score (CS, n = 8,991) recorded in four seasons per year from 2 to 6 yr of age were used to estimate breed-group differences. The mixed models included cow age, season of measurement and their interactions, year of birth, pregnancy-lactation code (PL), and breed group as fixed effects for CW and CS. Analyses of weight adjusted for condition score included CS as a linear covariate. Model for CH excluded PL. Random effects were additive genetic and permanent environmental effects. Differences among breed-groups were significant for all traits for different ages and were maintained across ages, with few interchanges in ranking through maturity. Cows with Sahiwal sires were lightest (392 to 479 kg), whereas Hereford-Angus (HA) reciprocal-cross cows were shortest (119 to 123 cm) at each age. Cows with Brahman sires were heaviest and tallest among breed groups at all ages, exceeding HA cows by 19 to 24 kg and 9 to 10 cm, respectively. Cows with Pinzgauer and Tarentaise sires were intermediate for weight and height and interchanged ranking across ages. Differences in weight due to differences in condition seemed to be of small magnitude because adjustment for condition score did not affect rankings of breed groups across ages. Important changes for mature size of cows can be achieved by breed substitution with the breeds of sires used in this study.
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- 2002
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15. Comparisons of Angus-, Braunvieh-, Chianina-, Hereford-, Gelbvieh-, Maine Anjou-, and Red Poll-sired cows for weight, weight adjusted for body condition score, height, and body condition score1
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Arango, J. A., Cundiff, L. V., and Van Vleck, L. D.
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Data from Angus, Hereford, and topcross cows (n = 641) from 2- to 8-yr-old daughters of seven breeds of sires included in Cycle II of the Germplasm Evaluation Program at the U.S. Meat Animal Research Center, comprising cow weight (CW, n = 15,698), height (CH, n = 15,676), and condition score (CS, n = 15,667), were used to estimate breed-group differences. Data were recorded in four seasons of each year (1975 to 1982). The mixed model included cow age, season of measurement, and their interactions, year of birth, pregnancy-lactation code (PL), and breed-group as fixed effects for CW and CS. Analyses of weight adjusted for condition score included CS as covariate. The model for CH excluded PL. Random effects were additive genetic and permanent environmental effects. Differences among breed-groups were significant for all traits at different ages and were maintained across ages, with few interchanges in ranking through maturity. Cows were ranked (by breed of sire) in the following order for weight: Red Poll (lightest), Hereford-Angus (reciprocal), Braunvieh, Gelbvieh, Maine Anjou, and Chianina (heaviest). In general, cows sired by breeds of British origin were lighter and shorter than those of continental origin. Differences in weight due to differences in condition seemed to be of small magnitude because making an adjustment for condition score did not affect rankings of breed groups across ages. Differences among breed groups for height were consistent with differences for weight. Cows from Chianina sires were taller than Hereford-Angus cows by 14 to 15 cm across ages. In this study, breed of sire effects were significantly different for the mature size of their daughters.
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- 2002
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16. Breed comparisons of Angus, Charolais, Hereford, Jersey, Limousin, Simmental, and South Devon for weight, weight adjusted for body condition score, height, and body condition score of cows1,2
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Arango, J. A., Cundiff, L. V., and Van Vleck, L. D.
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Breed means and differences for weight (CW, n = 19,851), height (CH, n = 14,553), and condition scores (CS, n = 19,536) recorded in four seasons per year were evaluated for 881 cows ranging from 2 to 7 yr of age from Cycle I of the Germplasm Evaluation Program at the U.S. Meat Animal Research Center. Cows were straightbred Herefords and Angus and topcrosses from mating of Hereford, Angus, South Devon, Jersey, Simmental, Limousin, and Charolais sires to Hereford and Angus dams. The model included cow age, season of measurement, and their interactions, with year of birth, pregnancy-lactation (PL) code, and breed group as fixed effects for CW and CS. Analyses of weight adjusted for condition score included CS as covariate. Model for CH excluded PL. Random effects were additive genetic and permanent environmental effects. Data were analyzed by REML. Differences due to breeds of sire were significant for all traits. Differences were generally maintained across ages, with few interchanges in ranking through maturity. Rankings were in the following order: Jersey (lightest and shortest), Hereford-Angus (and reciprocal), Limousin, South Devon, Simmental, and Charolais (heaviest and tallest). The only exception was that Limousin-sired cows were heavier than South Devon-sired cows after 5 yr of age. Cows sired by breeds of British origin tended to be lighter than breeds of continental European origin. Adjustment for condition score changed estimates of breed differences. Rankings of breed groups, however, were generally the same for actual weight and weight adjusted for condition score. Results indicated that the part of the differences in weight due to differences in condition were of small magnitude. Differences tended to increase when adjusted for condition score, especially in contrasts of continental vs British breeds. Differences among breed groups for height followed differences for weight closely.
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- 2002
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17. Genetic parameters for weight, weight adjusted for body condition score, height, and body condition score in beef cows1,2
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Arango, J. A., Cundiff, L. V., and Van Vleck, L. D.
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Weight (CW, n = 61,798), weight adjusted for condition score (WA), hip height (CH, n = 56,494), and condition score (CS, n = 61,434) of cows (2 through 8 yr of age) produced by crosses of 22 sire breeds with Angus and Hereford dams in the first four cycles of the Germplasm Evaluation (GPE) Program at the U.S. Meat Animal Research Center were used to estimate genetic parameters with REML. The model included sire breed, dam breed, age in years, season of measurement (1 to 4) and their interactions, and year of birth and pregnancy-lactation code (PL) as fixed effects for CW and CS. The model for CH excluded PL. Random effects were additive genetic and permanent environmental effects. Univariate analyses of all data, by season and by year of age, bivariate analyses between pairs of seasons and ages (2 to 6), and between traits were done. Estimates of heritability and repeatability over all ages were 0.49, 0.54, 0.68, and 0.16, and 0.65, 0.67, 0.75, and 0.30 for CW, WA, CH, and CS, respectively. Corresponding estimates for each age and season were similar for all traits and cycles. Estimates of genetic and permanent environmental correlations were close to unity for all pairs of seasons and traits. Genetic correlations were greater than 0.92 for all pairs of ages for CW, WA, and CH, and greater than 0.67 for CS. Genetic correlations were 0.80, 0.86, 0.43, and −0.04 for CW-CH, WA-CH, CW-CS, and CH-CS, respectively. Results suggest that repeatability models can be used to model weights and heights in this population.
- Published
- 2002
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18. Sex differences in mental illness: a community study of the influence of physical health and sociodemographic factors
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Vázquez-Barquero, J. L., Manrique, J. F. Diez, Muñoz, J., Arango, J. Menendez, Gaite, L., Herrera, S., and Der, G. J.
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This paper examines sex differences in psychiatric morbidity, using data from a community sample. The PSE-CATEGO-ID system was used to evaluate psychopathology. Six sociodemographic factors and physical illness were taken as independent variables. Females exhibit both a significantly higher psychiatric morbidity than males and a predominance of syndromes closely related to depression (SD; OD syndromes) and anxiety (GA; SA; TE; IT syndromes). Logistic modelling analysis, carried out separately for each sex, yielded different models. Psychiatric illness in men was best predicted by physical illness, unemployment and the interaction between the two. In contrast, physical illness emerged, in women, as the only factor exerting significant effects on psychiatric morbidity.
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- 1992
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19. The pathology of the posterior root ganglia in AIDS and its relationship to the pallor of the gracile tract
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Scaravilli, F., Sinclair, E., Arango, J. -C., Manji, H., Lucas, S., and Harrison, M. J. G.
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The spinal cord and the thoracic and lumbar posterior root ganglia (PRGs) of 14 HIV-positive men and 7 age- and sex-matched controls were studied by routine histology, morphometric analysis of the number of nodules of Nageotte (nN) and the diameters of sensory ganglion cells, immunohistochemistry and in situ hybridization. In 7 patients (2 of whom had evidence of cytomegalovirus ganglionitis) there were increased numbers of nN and diffuse, mild infiltration with CD45R
+ T lymphocytes; no B lymphocytes were observed. Macrophages were increased in number in all cases. Whenever more than one ganglion was examined from the same patient, the appearances were similar in all. There was no alteration in the distribution of ganglion cell diameters. Changes in the spinal cord included vacuolar myelopathy (5 cases), HIV myelitis (1 case), microglial nodules (3 cases) and pallor of the gracile tracts (GTP) in 7 cases, in 6 of whom it co-existed with increased numbers of nN. Seven cases had no abnormalities, except the increase in number of macrophages in PRGs. In spite of a correlation between sensory nerve cell loss and GTP our findings suggest that other mechanisms, such as ‘dying back’ may contribute to the pathogenesis of GTP. Moreover, sensory disturbances were found most commonly in association with nerve cell loss; however, loss of sensory ganglion cells was not necessarily associated with evidence of sensory impairment.- Published
- 1992
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20. Cyclohexenyl Nucleosides and Related Compounds
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Arango, J. H., Geer, A., Rodriguez, J., Young, P. E., and Scheiner, P.
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Cis and trans-1-(4-hydroxy-2-cyclohexenyl)- and 1-(2-hydroxy-5-cyclohexenyl) thymines were obtained by stereospecific routes. Oxidation of the 1, 4-products afforded 1-(4-oxo-2-cyclohexenyl)thymine, the carbocyclic analog of a reportedly antiviral ketopyranosyl nucleoside. Exclusive 1, 6-conjugate addition occurred with heterocyclic bases and methyl 1, 3-cyclohexadiene-1-carboxylate. Reduction of the thymine adduct gave 1-(4-hydroxymethyl1-3-cyclohexenyl)thymine. Michael-type addition provided a direct route to 3-oxocycloalkyl nucleosides, and lactone nucleosides resulted from addition of bases to α-methylene-γ-butyrolactone. Anti-HIV screening revealed no activity for the new compounds.
- Published
- 1993
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21. Effectiveness of Two New Cephalosporins, Cephazolin and Cephapirin, Administered Intermittently in Acute and Chronic Osteomyelitis in Children
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Arango, J L, Trujillo, H, Worren, D, Uribe, A, Agudelo, Nancy H, and de Vidal, Esther Luisa
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Ten patients were treated, most of pre-school age, with acute osteomyelitis, produced by Staphylococcus aureus and Salmonella, having evolved for approximately one week, with sodium cephazolin at doses of 60 mg/kg/day intramuscularly in two daily injections for the first seven days and then in a single dose every twenty-four hours for four to seven weeks. Nine of ten patients were asymptomatic six months after this treatment. The patient who manifested chronic signs at the end of six weeks of therapy continued to be treated with three weekly injections of the same drug at an equal dose until the completion of six months, at the end of which he was asymptomatic.Ten patients with chronic osteomyelitis having evolved for two months to five years, due to penicillin-resistant Staphylococcus aureus, were treated with cephapirin at the dose of 30 mg/kg in one daily injection intramuscularly for three to four weeks and then the same dose on Mondays, Wednesdays and Fridays until the completion of six months. Eight patients who required it were sequestrectomized. Seven of the ten patients improve and remained asymptomatic for the same period of observation. The three patients who did not show marked clinical improvement did exhibit an appreciable radiological recovery.We have presented these regimens of treatment with a view to encouraging research into the intermittent administration of bactericidal antibiotics for pyogenic infections; in spite of the good results, we do not dare to recommend them in daily practice.
- Published
- 1976
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22. Rous sarcoma virus-transformed baby hamster kidney cells express higher levels of asparagine-linked tri- and tetraantennary glycopeptides containing [GlcNAc-beta (1,6)Man-alpha (1,6)Man] and poly-N-acetyllactosamine sequences than baby hamster kidney cells.
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Pierce, M and Arango, J
- Abstract
The alterations in complex-type N-linked oligosaccharides that can occur when an animal cell line is transformed by two dissimilar viruses were examined by comparing the N-linked oligosaccharides of baby hamster kidney (BHK) cells, metabolically radiolabeled with [2-3H]mannose, to the same class of oligosaccharides from BHK cells separately transformed by Rous sarcoma virus (RS-BHK), an RNA retrovirus, and polyoma virus (PY-BHK), a DNA papovavirus. Based on experiments that utilized serial lectin affinity chromatography, glycosidase digestions, and methylation analyses, both RS-BHK and PY-BHK cells demonstrated a significant increase in the relative amounts of tri- and tetraantennary complex-type N-linked oligosaccharides containing the branching sequence, [GlcNAc-beta(1,6)Man-alpha(1,6)Man], compared to the nontransformed BHK cells. In addition, almost all of the poly-N-acetyllactosamine sequence, [GlcNAc-beta(1,3)-Gal-beta(1,4)], was expressed on the tri- and tetraantennary N-linked oligosaccharides from BHK and RS-BHK cells that contain the sequence, [GlcNAc-beta(1,6)Man-beta(1,6)Man]. The increase in the relative amounts of this latter sequence in the transformed cells, therefore, most likely results in an increase in the amount of poly-N-acetyllactosamine sequence on the N-linked glycopeptides of these cells. The analysis of the degree of sialylation of the complex-type N-linked oligosaccharides from BHK and RS-BHK cells by ion exchange chromatography revealed no apparent differences, and in both of these cell types approximately 3% of the glycopeptide fraction radiolabeled with mannose was recovered in a highly negatively charged fraction that was identified by keratanase digestion to be keratan sulfate.
- Published
- 1986
- Full Text
- View/download PDF
23. THE HISTORY OF THE MOSQUITOMALARIA THEORY—II
- Author
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Jaramillo‐Arango, J.
- Published
- 1948
- Full Text
- View/download PDF
24. A CLN5mutation causing an atypical neuronal ceroid lipofuscinosis of juvenile onset
- Author
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Pineda-Trujillo, N, Cornejo, W, Carrizosa, J, Wheeler, R B., Múnera, S, Valencia, A, Agudelo-Arango, J, Cogollo, A, Anderson, G, Bedoya, G, Mole, S E., and Ruíz-Linares, A
- Abstract
Three related patients from Colombia presented with a juvenile-onset neuronal ceroid lipofuscinosis. Electron microscopy of one case showed condensed fingerprint profiles, and genetic analyses identified a novel missense mutation in CLN5. The authors demonstrate the existence of pathogenic CLN5mutations outside northern Europe and that mutations in this gene can lead to an atypical late-onset neuronal ceroid lipofuscinosis disease, in addition to the late infantile form first described in Finland.
- Published
- 2005
- Full Text
- View/download PDF
25. Rapid communication: mapping of the Steroidogenic Acute Regulatory Protein(StAR) gene to porcine chromosome 15 by linkage analysis using a novel PCR-RFLP1
- Author
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Splan, R. K., Pilcik, B. R., Tomsen, U. J., Arango, J. A. G., Ruiz-Flores, A., Hallock, J. W., Allan, M. F., Karnati, S. K. R., Vega, V., Lindsey, B. R., Moody, D. E., and Pomp, D.
- Published
- 1998
- Full Text
- View/download PDF
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