A Novel Imaging Protocol for Investigating Arabidopsis thaliana Siliques and Seeds Using X-rays.

Understanding silique and seed morphology is essential to developmental biology. Arabidopsis thaliana is one of the best-studied plant models for understanding the genetic determinants of seed count and size. However, the small size of its seeds, and their encasement in a pod known as silique, makes investigating their numbers and morphology both time consuming and tedious. Researchers often report bulk seed weights as an indicator of average seed size, but this overlooks individual seed details. Removal of the seeds and subsequent image analysis is possible, but automated counts are often impossible due to seed pigmentation and shadowing. Traditional ways of analyzing seed count and size, without their removal from the silique, involve lengthy histological processing (24-48 h) and the use of toxic organic solvents. We developed a method that is non-invasive, requires minimal sample processing, and obtains data in a short period of time (1-2 h). This method uses a custom X-ray imaging system to visualize Arabidopsis siliques at different stages of their growth. We show that this process can be successfully used to analyze the overall topology of Arabidopsis siliques and seed size and count. This new method can be easily adapted for other plant models. Key features • No requirement for organic solvents for imaging siliques. • Easy image capture and rapid turnaround time for obtaining data. • Protocol may be easily adapted for other plant models.

The Future of Neurocritical Care Research: Proceedings and Recommendations from the Fifth Neurocritical Care Research Network Conference.

The Fifth Neurocritical Care Research Network (NCRN) Conference held in Boca Raton, Florida, in September of 2018 was devoted to challenging the current status quo and examining the role of the Neurocritical Care Society (NCS) in driving the science and research of neurocritical care. The aim of this in-person meeting was to set the agenda for the NCS's Neurocritical Care Research Central, which is the overall research arm of the society. Prior to the meeting, all 103 participants received educational content (book and seminar) on the 'Blue Ocean Strategy®,' a concept from the business world which aims to identify undiscovered and uncontested market space, and to brainstorm innovative ideas and methods with which to address current challenges in neurocritical care research. Three five-member working groups met at least four times by teleconference prior to the in-person meeting to prepare answers to a set of questions using the Blue Ocean Strategy concept as a platform. At the Fifth NCRN Conference, these groups presented to a five-member jury and all attendees for open discussion. The jury then developed a set of recommendations for NCS to consider in order to move neurocritical care research forward. We have summarized the topics discussed at the conference and put forward recommendations for the future direction of the NCRN and neurocritical care research in general.

"Candidatus Accumulibacter delftensis": A clade IC novel polyphosphate-accumulating organism without denitrifying activity on nitrate.

Populations of "Candidatus Accumulibacter", a known polyphosphate-accumulating organism, within clade IC have been proposed to perform anoxic P-uptake activity in enhanced biological phosphorus removal (EBPR) systems using nitrate as electron acceptor. However, no consensus has been reached on the ability of "Ca. Accumulibacter" members of clade IC to reduce nitrate to nitrite. Discrepancies might relate to the diverse operational conditions which could trigger the expression of the Nap and/or Nar enzyme and/or to the accuracy in clade classification. This study aimed to assess whether and how certain operational conditions could lead to the enrichment and enhance the denitrification capacity of "Ca. Accumulibacter" within clade IC. To study the potential induction of the denitrifying enzyme, an EBPR culture was enriched under anaerobic-anoxic-oxic (A2O) conditions that, based on fluorescence in situ hybridization and ppk gene sequencing, was composed of around 97% (on a biovolume basis) of affiliates of "Ca. Accumulibacter" clade IC. The influence of the medium composition, sludge retention time (SRT), polyphosphate content of the biomass (poly-P), nitrate dosing approach, and minimal aerobic SRT on potential nitrate reduction were studied. Despite the different studied conditions applied, only a negligible anoxic P-uptake rate was observed, equivalent to maximum 13% of the aerobic P-uptake rate. An increase in the anoxic SRT at the expenses of the aerobic SRT resulted in deterioration of P-removal with limited aerobic P-uptake and insufficient acetate uptake in the anaerobic phase. A near-complete genome (completeness = 100%, contamination = 0.187%) was extracted from the metagenome of the EBPR biomass for the here-proposed "Ca. Accumulibacter delftensis" clade IC. According to full-genome-based phylogenetic analysis, this lineage was distant from the canonical "Ca. Accumulibacter phosphatis", with closest neighbor "Ca. Accumulibacter sp. UW-LDO-IC" within clade IC. This was cross-validated with taxonomic classification of the ppk1 gene sequences. The genome-centric metagenomic analysis highlighted the presence of genes for assimilatory nitrate reductase (nas) and periplasmic nitrate reductase (nap) but no gene for respiratory nitrate reductases (nar). This suggests that "Ca. Accumulibacter delftensis" clade IC was not capable to generate the required energy (ATP) from nitrate under strict anaerobic-anoxic conditions to support an anoxic EBPR metabolism. Definitely, this study stresses the incongruence in denitrification abilities of "Ca. Accumulibacter" clades and reflects the true intra-clade diversity, which requires a thorough investigation within this lineage.

Comparative evaluation of supplemental zilpaterol hydrochloride sources on growth performance, dietary energetics and carcass characteristics of finishing lambs.

OBJECTIVE: We compare the effects of three different approved sources of supplemental zilpaterol on growth-performance responses and carcass characteristics of finishing lambs. METHODS: Twenty four Pelibuey×Katahdin lambs (46.75±2.43 kg) were used in a 33-day feeding trial. Lambs were fed a dry rolled corn-based finishing diet. Treatments consisted of the non-supplemental basal diet (Control) versus the basal diet supplemented with 125 mg zilpaterol/kg of diet (as fed basis) from three commercial sources marketed in Mexico: Zilmax (ZIL), Grofactor, and Zipamix. RESULTS: Compared to controls, zilpaterol (ZH) supplementation did not affect dry matter intake (DMI), but increased carcass adjusted daily weight gain (ADG, 36.7%), gain efficiency (34.2%), and dietary net energy (26.0%), and decreased (23.4%) the ratio of observed:expected DMI. Compared to controls, supplemental ZH increased hot carcass weight (6.4%), dressing percentage (3.2%), m. longissimus thoracis (LM) area (15.6%), and shoulder muscle:fat ratio (28.7%), but decreased kidney-pelvic-heart fat, and fat thickness. Supplemental ZH increased 10.9% and 14.3% whole cut weight of loin and leg, respectively, and the proportion (as percentage of cold carcass weight) of leg (4.3%). These increases were reflected in greater forequarter and hindquarter weights. Lambs fed ZH increased (4.6%) empty body weight (EBW) and reduced (14.7%) liver/spleen weight (as g/kg EBW). Likewise, ZH supplementation tended (p = 0.08) to lower (8.9%) visceral fat. Growth performance, energetic efficiency, hot carcass weight, dressing percentage, LM area and whole cuts were not different across supplemental ZH sources. However, compared with non-supplemented controls, only ZIL appreciably decreased carcass fat distribution, including fat thickness, percentage kidney pelvic and heart fat, shoulder fat, and visceral fat. CONCLUSION: Supplemental ZH increases ADG, gain efficiency, carcass dressing percentage, and LM area. The magnitude of these responses was similar among ZH sources. Nevertheless, compared with non-supplemented controls, only ZIL appreciably decreases carcass fat. The basis for this is uncertain, but indicative that some practical differences in zilpaterol bio-equivalency may exist across commercial sources tested.

Spanish validation of the PAS-ADD Checklist Questionnaire for people with intellectual disabilities for Spanish population.

BACKGROUND: The Psychiatric Assessment Schedule for Adult with Developmental Disability (PAS-ADD) is an international reference tool for the diagnosis and assessment of mental health problems and behavioural disorders among people with intellectual disabilities. Although the original PAS-ADD instrument has been validated in the Spanish language, the shorter PAS-ADD Checklist has yet not been validated. The aim of this study is to validate the PAS-ADD Checklist for the Spanish population. METHODS: The PAS-ADD Checklist Questionnaire was administered to 208 adults with intellectual disabilities at a vocational centre in Madrid, Spain. The psychometric analyses included internal consistency, inter-rater and test-retest reliability, Varimax rotation factor analysis for construct validity, criterion validity and feasibility. RESULTS: The Cronbach's alpha was 0.80 for the overall questionnaire and between 0.40 and 0.79 for the subscales. The Kappa coefficients for test-retest and inter-rater reliability were between 0.66 and 0.80. Varimax rotation factor analysis showed five well-defined factors. The Kappa coefficients for criterion validity were between 0.30 and 0.70. Feasibility was also good. CONCLUSIONS: The PAS-ADD Checklist is a feasible and reliable instrument for carrying out initial assessment of the mental health status of adults with intellectual disabilities, referring cases to more specialised diagnosis and treatment.

Cooperation between Candidatus Competibacter and Candidatus Accumulibacter clade I, in denitrification and phosphate removal processes.

Although simultaneous P-removal and nitrate reduction has been observed in laboratory studies as well as full-scale plants, there are contradictory reports on the ability of PAO I to efficiently use nitrate as electron acceptor. Such discrepancy could be due to other microbial groups performing partial denitrification from nitrate to nitrite. The denitrification capacities of two different cultures, a highly enriched PAO I and a PAO I-GAO cultures were assessed through batch activity tests conducted before and after acclimatization to nitrate. Negligible anoxic phosphate uptake coupled with a reduction of nitrate was observed in the highly enriched PAO I culture. On the opposite, the PAO I-GAO culture showed a higher anoxic phosphate uptake activity. Both cultures exhibited good anoxic phosphate uptake activity with nitrite (8.7 ± 0.3 and 9.6 ± 1.8 mgPO4-P/gVSS.h in the PAO I and PAO I-GAO cultures, respectively). These findings suggest that other microbial populations, such as GAOs, were responsible to reduce nitrate to nitrite in this EBPR system, and that PAO I used the nitrite generated for anoxic phosphate uptake. Moreover, the simultaneous denitrification and phosphate removal process using nitrite as electron acceptor may be a more sustainable process as can: i) reduce the carbon consumption, ii) reduce oxygen demand of WWTP, and iii) due to a lower growth yield contribute to a lower sludge production.

Long-term effects of sulphide on the enhanced biological removal of phosphorus: The symbiotic role of Thiothrix caldifontis.

Thiothrix caldifontis was the dominant microorganism (with an estimated bio-volume of 65 ± 3%) in a lab-scale enhanced biological phosphorus removal (EBPR) system containing 100 mg of sulphide per litre in the influent. After a gradual exposure to the presence of sulphide, the EBPR system initially dominated by Candidatus Accumulibacter phosphatis Clade I (98 ± 3% bio-volume) (a known polyphosphate accumulating organism, PAO) became enriched with T. caldifontis. Throughout the different operating conditions studied, practically 100% phosphate removal was always achieved. The gradual increase of the sulphide content in the medium (added to the anaerobic stage of the alternating anaerobic-aerobic sequencing batch reactor) and the adjustment of the aerobic hydraulic retention time played a major role in the enrichment of T. caldifontis. T. caldifontis exhibited a mixotrophic metabolism by storing carbon anaerobically as poly-ß-hydroxy-alkanoates (PHA) and generating the required energy through the hydrolysis of polyphosphate. PHA was used in the aerobic period as carbon and energy source for growth, polyphosphate, and glycogen formation. Apparently, extra energy was obtained by the initial accumulation of sulphide as an intracellular sulphur, followed by its gradual oxidation to sulphate. The culture enriched with T. caldifontis was able to store approximately 100 mg P/g VSS. This research suggests that T. caldifontis could behave like PAO with a mixotrophic metabolism for phosphorus removal using an intracellular sulphur pool as energy source. These findings can be of major interest for the biological removal of phosphorus from wastewaters with low organic carbon concentrations containing reduced S-compounds like those (pre-)treated in anaerobic systems or from anaerobic sewers.

Effect of immunocastration with Bopriva on carcass characteristics and meat quality of feedlot Holstein bulls.

To evaluate the effect of immunocastration on carcass and meat characteristics, Holstein bulls aged between 7 and 8months with a live weight of 232±1.19kg were given two separate treatments, placebo (intact bulls) versus Bopriva, and then slaughtered after approximately 239days of fattening. While the testosterone levels in intact bulls remained at 0.42ng/ml throughout the study, by day 181, differences (P<0.05) were observed in immunized bulls, with values of 0.21ng/ml. The carcasses of animals treated with Bopriva recorded both a higher hot carcass weight (HCW) and a cold carcass weight (CCW), as well as higher dorsal fat density, marbling and KPH (P<0.05); however, no differences (P>0.05) were observed in the Longissimus lumborum area. No significant differences (P>0.05) were recorded between the treatments for pH, L*, a*, b* C* and H*. The carcasses of the animals treated with Bopriva were heavier, with higher dorsal fat density and marbling score.

Sulphide effects on the physiology of Candidatus Accumulibacter phosphatis type I.

Sulphate-rich wastewaters can be generated due to (i) use of saline water as secondary-quality water for sanitation in urban environments (e.g. toilet flushing), (ii) discharge of industrial effluents, (iii) sea and brackish water infiltration into the sewage and (iv) use of chemicals, which contain sulphate, in drinking water production. In the presence of an electron donor and absence of oxygen or nitrate, sulphate can be reduced to sulphide. Sulphide can inhibit microbial processes in biological wastewater treatment systems. The objective of the present study was to assess the effects of sulphide concentration on the anaerobic and aerobic physiology of polyphosphate-accumulating organisms (PAOs). For this purpose, a PAO culture, dominated by Candidatus Accumulibacter phosphatis clade I (PAO I), was enriched in a sequencing batch reactor (SBR) fed with acetate and propionate. To assess the direct inhibition effects and their reversibility, a series of batch activity tests were conducted during and after the exposure of a PAO I culture to different sulphide concentrations. Sulphide affected each physiological process of PAO I in a different manner. At 189 mg TS-S/L, volatile fatty acid uptake was 55% slower and the phosphate release due to anaerobic maintenance increased from 8 to 18 mg PO4-P/g VSS/h. Up to 8 mg H2S-S/L, the decrease in aerobic phosphorus uptake rate was reversible (Ic60). At higher concentrations of sulphide, potassium (>16 mg H2S-S/L) and phosphate (>36 mg H2S-S/L) were released under aerobic conditions. Ammonia uptake, an indicator of microbial growth, was not observed at any sulphide concentration. This study provides new insights into the potential failure of enhanced biological phosphorus removal sewage plants receiving sulphate- or sulphide-rich wastewaters when sulphide concentrations exceed 8 mg H2S-S/L, as PAO I could be potentially inhibited.

Estimation of genetic and phenotypic parameters for production traits in Holstein and Jersey from Colombia / Estimación de parámetros genéticos y fenotípicos para características de producción en ganado Holstein y Jersey Colombiano

Objective. Determine the genetic and phenotypic parameters for milk yield, fat percentage, protein percentage and somatic cell score. Materials and methods. 18134 lactation records were used to Holstein and 1377 lactations for Jersey in different herds. The (co) variance components and genetic parameters were estimated using the software Multiple Trait Derivative-Free Restricted Maximum Likelihood MTDFREML. Results. The Holstein and Jersey heritability's (and standard error) for milk yield were: 0.16 (0.082) and 0.15 (0.306), 0.30 (0.079) and 0.37 (0.319) for protein percentage, 0.32 (0.076) and 0.46 (0.313) for fat percentage and for somatic cell score were: 0.01 (0.054) and 0.01 (0.233), respectively. The largest genetic correlations were found between the percentage of fat and percentage of protein, with values of 0.82 (0.126) and 0.98 (0.852) for Holstein and Jersey respectively. The lowest correlations were between fat percentage and somatic cell score with -0.01 (1.147) and -0.01 (1. 734). Phenotypic correlations were generally found low and repeatability showed a significant effect of permanent environment on milk production per lactation. Conclusions. It is important to emphasize the development of research to help guide breeding programs in the tropics, using selection indices of multi-traits.

Objetivos. Determinar los parámetros genéticos y fenotípicos para producción de leche, porcentaje de grasa, porcentaje de proteína y puntaje de células somáticas. Materiales y métodos. Se utilizó información de 18134 lactancias para Holstein y 1377 para Jersey de diferentes hatos del departamento de Antioquia (Colombia). La determinación de los componentes de varianza, covarianza y los parámetros genéticos se realizó mediante el método de máxima verosimilitud restricta libre de derivadas usando el programa MTDFREML. Resultados. La heredabilidad y el error estándar en Holstein y Jersey para producción de leche fueron 0.16 (0.082) y 0.15 (0.306), para porcentaje de proteína 0.30 (0.079) y 0.37 (0.319), para el porcentaje de grasa de 0.32 (0.076) y 0.46 (0.313) y para el puntaje de células somáticas fue de 0.01 (0.054) y 0.01 (0.233), respectivamente. Las mayores correlaciones genéticas encontradas fueron entre porcentaje de grasa y porcentaje de proteína, con valores de 0.82 (0.126) y 0.98 (0.852) para Holstein y Jersey, respectivamente. La menores correlaciones fueron obtenidas entre porcentaje de grasa y puntaje de células somáticas con valores de -0.01 (1.147) y -0.01 (1.734), respectivamente. Las correlaciones fenotípicas encontradas por lo general fueron bajas y la repetibilidad evidenció un efecto importante del ambiente permanente sobre la producción de leche por lactancia. Conclusiones. El presente trabajo encuentra algunas diferencias con los reportes de parámetros genéticos en otros países, lo que resalta la importancia del desarrollo de trabajos de investigación que permitan orientar los programas de mejoramiento genético en el trópico.

Estimation and comparison of conventional and genomic breeding values in Holstein cattle of Antioquia, Colombia / Estimación y comparación de valores de cría convencionales y genómicos en ganado Holstein de Antioquia, Colombia

Objective. To estimate and compare breeding values (EBV) using the conventional method (BLUP) and genomic breeding values (MEBV and GEBV) estimated through bayes C method for milk yield and milk quality traits in dairy cattle in Antioquia, Colombia. Materials and methods. Two methods were used to estimate breeding values: BLUP to estimate conventional breeding value (EBV) and bayes C to estimate genomic values (MEBV and GEBV). The traits evaluated were: milk yield (PL), protein percentage (PPRO), fat percentage (PGRA) and score somatic cell (SCS). The methods (BLUP and bayes C) were compared using Person correlation (r p), Spearman rank correlation (r s) and linear regression coefficient (b). Results. The Pearson and Spearman correlations among EBVs and genomic values (MEBV and GEBV) (r pMEBV;EBV and r sGEBV;EBV) were greater than 0.93 and the linear regression coefficients of EBVs on genomic values (MEBV and GEBV) (bMEBV;EBV, and bGEBV;EBV) ranged between 0.954 and 1.051 in all traits evaluated. Conclusions. The predictions of genomic values (MEBV and GEBV), using bayes C method were consistent with the predictions of the EBVs estimate through the conventional method (BLUP) in conditions of high Colombian tropic, allowing to obtain high associations between the breeding values.

Objetivo. Estimar y comparar valores genéticos (EBV) usando el método convencional (BLUP) y valores genómicos (MEBV y GEBV) mediante el método bayes C en características de producción y calidad de la leche en ganado Holstein de Antioquia, Colombia. Materiales y métodos. Fueron empleados dos métodos para estimar valores genéticos: BLUP para estimar valores genéticos (EBV) y Bayes C para estimar valores genómicos (MEBV y GEBV). Las características evaluadas fueron: producción de leche (PL), porcentaje de proteína (PPRO), porcentaje de grasa (PGRA) y puntaje de células somáticas (SCS). Los métodos BLUP y bayes C fueron comparadas usando correlación de Pearson (r p), correlación por rangos de Spearman (r s) y regresión lineal (b). Resultados. Las correlaciones de Pearson y Spearman entre los EBVs y los valores genómicos (MEBV y GEBV) (r pMEBV;EBV y r sGEBV;EBV) fueron mayores de 0.93 y los coeficientes de regresión entre los EBVs y los valores genómicos (MEBV y GEBV) (bMEBV;EBV, y bGEBV;EBV) oscilaron entre 0.954 y 1.051 en todas las características evaluadas. Conclusiones. La predicción de valores genómicos (MEBV y GEBV) usando el método Bayes C fue consistente con los EBVs estimados mediante el método BLUP en condiciones del trópico alto colombiano, permitiendo obtener altas asociaciones entre los valores genéticos.

Influence of protein and energy level in finishing diets for feedlot hair lambs: growth performance, dietary energetics and carcass characteristics.

Forty-eight Pelibuey×Katahdin male intact lambs (23.87±2.84 kg) were used in an 84-d feeding trial, with six pens per treatment in a 2×2 factorial design arrangement. The aim of the study was to evaluate the interaction of two dietary energy levels (3.05 and 2.83 Mcal/kg ME) and two dietary protein levels (17.5% and 14.5%) on growth performance, dietary energetics and carcass traits. The dietary treatments used were: i) High protein-high energy (HP-HE); ii) High protein-low energy (HP-LE); iii) Low protein-high energy (LP-HE), and iv) Low protein-low energy (LP-LE). With a high-energy level, dry matter intake (DMI) values were 6.1% lower in the low-protein diets, while with low-energy, the DMI values did not differ between the dietary protein levels. Energy levels did not influence the final weight and average daily gain (ADG), but resulted in lower DMI values and higher gain efficiencies. No effects of protein level were detected on growth performance. The observed dietary net energy (NE) ratio and observed DMI were closer than expected in all treatments and were not affected by the different treatments. There was an interaction (p<0.03) between energy and protein level for kidney-pelvic and heart fat (KPH), KPH was higher in lambs fed high energy and high protein diet but not in high energy and low protein diet. The KPH was increased (20.2%, p = 0.01) in high-energy diets, while fat thickness was increased (21.7%, p = 0.02) in high-protein diets. Therefore, it is concluded that dietary energy levels play a more important role in feed efficiency than protein levels in finishing lambs with a high-energy diet (>2.80 Mcal/kg ME). Providing a level of protein above 14.5% does not improves growth-performance, dietary energetics or carcass dressing percentage.

Detection of key factors affecting lycopene in vitro accessibility.

On the basis of a Plackett-Burman experimental design for a resolution IV level obtained via a foldover strategy, the effect of 11 factors on lycopene in vitro accessibility was investigated. The selected factors were thermal treatment (X1), olive oil addition (X2), gastric pH (X3), gastric digestion time (X4), pepsin concentration (X5), intestinal pH (X6), pancreatin concentration (X7), bile salts concentration (X8), colipase addition (X9), intestinal digestion time (X10), and intestinal digestion speed (X11). Tomato passata was used as a natural source of lycopene. Samples were collected after gastric and intestinal digestion, and from the micellar phase, to quantify the (all-E)-lycopene and its (Z)-isomers by HPLC. Except for X3, X6, X7, and X11, the other factors studied explained lycopene in vitro accessibility, mainly regarding intestinal digestion, with R(2) values ≥ 0.60. Our results showed that the accessibility of lycopene is influenced by the conditions applied during in vitro intestinal digestion.

Acute respiratory distress syndrome and acute lung injury in patients with vertebral column fracture(s) and spinal cord injury: a nationwide inpatient sample study.

STUDY DESIGN: Retrospective Nationwide Inpatient Sample (NIS) study. OBJECTIVES: To determine national trends in prevalence, risk factors and mortality for vertebral column fracture (VCF) and spinal cord injury (SCI) patients with and without acute respiratory distress syndrome/acute lung injury (ARDS/ALI). SETTING: United States of America, 1988 to 2008. METHODS: The NIS was utilized to select 284 612 admissions for VCF with and without acute SCI from 1988 to 2008 based on ICD-9-CM. The data were stratified for in-hospital complications of ARDS/ALI. RESULTS: Patients with SCI were more likely to develop ARDS/ALI compared with those without (odds ratio (OR): 4.9, 95% confidence interval (CI) 4.7-5.2, P<0.001). Compared with patients with lumbar fractures, those with cervical, thoracic and sacral fractures were more likely to develop ARDS/ALI (P<0.001). ARDS/ALI was statistically more prevalent (P<0.01) in VCF/SCI patients with epilepsy, sepsis, cardiac arrest, congestive heart failure (CHF), hypertension, chronic obstructive pulmonary disease and metabolic disorders. Patients with female gender, surgery at rural practice setting, and coronary artery disease and diabetes were less likely to develop ARDS/ALI (P<0.001). VCF/SCI patients who developed ARDS/ALI were more likely to die in-hospital than those without ARDS/ALI (OR 6.5, 95% CI 6.0-7.1, P<0.001). Predictors of in-hospital mortality after VCF/SCI include: older age, male sex, epilepsy, sepsis, hypertension, CHF, chronic obstructive pulmonary disease and liver disease. Patients who developed ARDS/ALI stayed a mean of 25 hospital days (30-440 days) while patients without ARDS/ALI stayed a mean of 6 days (7-868 days, P<0.001). CONCLUSION: Our analysis demonstrates that SCI patients are more at risk for ARDS/ALI, which carries a significantly higher risk of mortality.

Estructura y diversidad genética en vacas Holstein de Antioquia usando un polimorfismo del gen bGH / Structure and Genetic Diversity of a population Holstein cows of Antioquia department, using a polymorphism of bGH gene

Objetivo. Determinar las frecuencias alélicas y genotípicas del polimorfismo del intrón 3 del gen bGH y estimar algunos parámetros de estructura poblacional en ganado Holstein. Materiales y métodos. El estudio se realizó con 1366 vacas Holstein en 120 hatos de 11 municipios del departamento de Antioquia. Se extrajo DNA por el método de Salting out y la genotipificación se realizó usando la técnica de PCR-RFLPs. La diversidad genética se determinó mediante la comparación de las heterocigosidades, El equilibrio de Hardy-Weinberg (HW) y la diferenciación genética entre las poblaciones se realizó usando el software Arlequín 2.0 Las frecuencias alélicas y genotípicas se evaluaron mediante el paquete estadístico SAS®. Resultados. Las frecuencias genotípicas encontradas fueron 0.764 (+/+), 0.223 (+/-) y 0.013 (-/-) y las frecuencias alélicas 0.876 (+) y 0.124 (-). No se encontraron desviaciones del Equilibrio de Hardy Weinberg en ninguna de las subpoblaciones. La diversidad genética determinada mediante la comparación de las heterocigosidades fue relativamente baja entre poblaciones pero al interior de estas no. El valor de FST de toda la población fue de 0.0068 y significativo (p<0.05), algunos FST pareados también lo fueron, tomando valores desde 0.0 a 0.13. Los estadísticos FIT y FIS no fueron significativos. Conclusiones. El gen bGH es un candidato interesante para evaluar características de importancia económica ya que no parece haber sido sometido a selección directa, presenta una variabilidad media en las poblaciones, observándose diferenciación genética significativa entre distintos municipios, producto de los diferentes sistemas de producción y acceso a las biotecnologías.

Objective. To determine the allele frequencies and genotypic polymorphism of the intron 3 of gene bGH and estimate structural parameters in Holstein cattle populations. Materials and methods. The study was conducted with 1366 Holstein cows belonging to 120 herds in 11 municipalities of the department of Antioquia. DNA was extracted by the Salting out method and genotyping was carried out using PCR-RFLP. Genetic diversity was determined by comparing the heterozygosities, Hardy-Weinberg (HW) and genetic differentiation between populations was performed using the Arlequin software 3.0. The allelic and genotyping frequencies were assessed using the SAS statistical software. Results. The genotype frequencies found were 0.764 and 0.013 (+/-) 0.223 (+/+), (-/-) and allele frequencies were 0.876 (+) and 0124 (-). There was no unbalance for Hardy Weinberg in the subpopulations. The genetic diversity determined by comparison of the heterozygosity was low among populations but within them it was not. The FST value of the entire population was 0.0068 and significant (p<0.05), FST also matched some were values ranging from 0.0 to 0.13. The statistical FIT and FIS were not significant. Conclusions. The gene bGH is an interesting candidate to economically evaluate important traits because it does not seem to have been subject to direct selection, has a mean variability in populations, showing significant genetic differentiation between several municipalities, resulting from the different production systems and access to biotechnologies.

Effects of Replacing Dry-rolled Corn with Increasing Levels of Corn Dried Distillers Grains with Solubles on Characteristics of Digestion, Microbial Protein Synthesis and Digestible Energy of Diet in Hair Lambs Fed High-concentrate Diets.

Four male lambs (Katahdin; average live weight 25.9±2.9 kg) with "T" type cannulas in the rumen and proximal duodenum were used in a 4×4 Latin square experiment to evaluate the influence of supplemental dry distillers grain with solubles (DDGS) levels (0, 10, 20 and 30%, dry matter basis) in substitution for dry-rolled (DR) corn on characteristics of digestive function and digestible energy (DE) of diet. Treatments did not influence ruminal pH. Substitution of DR corn with DDGS increased ruminal neutral detergent fiber (NDF) digestion (quadratic effect, p<0.01), but decreased ruminal organic matter (OM) digestion (linear effect, p<0.01). Replacing corn with DDGS increased (linear, p≤0.02) duodenal flow of lipids, NDF and feed N. But there were no treatment effects on flow to the small intestine of microbial nitrogen (MN) or microbial N efficiency. The estimated UIP value of DDGS was 44%. Postruminal digestion of OM, starch, lipids and nitrogen (N) were not affected by treatments. Total tract digestion of N increased (linear, p = 0.04) as the DDGS level increased, but DDGS substitution tended to decrease total tract digestion of OM (p = 0.06) and digestion of gross energy (p = 0.08). However, it did not affect the dietary digestible energy (DE, MJ/kg), reflecting the greater gross energy content of DDGS versus DR corn in the replacements. The comparative DE value of DDGS may be considered similar to the DE value of the DR corn it replaced up to 30% in the finishing diets fed to lambs.

Periodic magnetorotational dynamo action as a prototype of nonlinear magnetic-field generation in shear flows.

The nature of dynamo action in shear flows prone to magnetohydrodynamc instabilities is investigated using the magnetorotational dynamo in Keplerian shear flow as a prototype problem. Using direct numerical simulations and Newton's method, we compute an exact time-periodic magnetorotational dynamo solution to three-dimensional dissipative incompressible magnetohydrodynamic equations with rotation and shear. We discuss the physical mechanism behind the cycle and show that it results from a combination of linear and nonlinear interactions between a large-scale axisymmetric toroidal magnetic field and nonaxisymmetric perturbations amplified by the magnetorotational instability. We demonstrate that this large-scale dynamo mechanism is overall intrinsically nonlinear and not reducible to the standard mean-field dynamo formalism. Our results therefore provide clear evidence for a generic nonlinear generation mechanism of time-dependent coherent large-scale magnetic fields in shear flows and call for new theoretical dynamo models. These findings may offer important clues to understanding the transitional and statistical properties of subcritical magnetorotational turbulence.

The roles of pH extraction and colloidal protein solubility in the optimization of spectrophotometric nitrite determination in meat products via response surface methodology.

The influence of four critical factors such as sample weight/borax reagent ratio (B(R) factor), ascorbic acid content (A(R) factor), neutralization with HCl 1N (N(R) factor) and stirring extraction time (S(ET) factor), was investigate in order to find the best conditions (optimization) to develop the official ISO 2.918 spectrophotometric method to determine the residual nitrite content in meat products, using the response surface methodology (RSM) as optimization tool. The factors most strongly affecting nitrite determination in meat products are B(R), N(R) and A(R), due to their respective effects on pH extraction parameters and on the amount of colloidal protein present in the sample extract. At pH⩽6, for example, the extract - though appearing clear and transparent to the analyst - contains a considerable amount of hydrolyzed protein, which will severely interfere with measurements, generating false-positive results. The colloidal protein present in the extract (⩽20mg/g, corresponding in these working conditions to an OD(340) value of ⩽0.600) will lead to the recording of nitrite values greater than those actually present in the sample. In order to avoid these drawbacks, this paper proposes that the amount of borax added (B(R)) varies as a function of sample weight (W(S)), using the ratio W(S)/B(R)=1.11. In order to monitor the analytical method, it is further recommended that pH be adjusted to 6-7 (lower protein solubility) and that colloidal protein levels be ⩾20mg/g, as confirmed by an OD(340) value of ⩾0.600.

Self-sustaining nonlinear dynamo process in Keplerian shear flows.

A three-dimensional nonlinear dynamo process is identified in rotating plane Couette flow in the Keplerian regime. It is analogous to the hydrodynamic self-sustaining process in nonrotating shear flows and relies on the magnetorotational instability of a toroidal magnetic field. Steady nonlinear solutions are computed numerically for a wide range of magnetic Reynolds numbers but are restricted to low Reynolds numbers. This process may be important to explain the sustenance of coherent fields and turbulent motions in Keplerian accretion disks, where all its basic ingredients are present.

FACO/LUZ: hacia la construcción de un modelo educativo integral en odontología (parteII) / FACO/LUZ: towards the contruction of integral an educative model in odontolgy (part II)

Caracterizar el plan de estudio vigentes de la Facultad de Odontología de la Universidad del Zulia y los fundamentos teóricos-metodológicos que sustentan su modelo educativo. Parte del análisis histórico de los cambios estructurales y funcionales que ha transitado la institución, el cual devela un marco epistemológico que reafirma su compromiso social. El estudio fue documental y descriptivo. El estudio de las fuentes documentales de tipo analítico - expositivo. El plan de estudio se estructura en función de áreas y ejes cuniculares que muestran correpondencia con los elementos estructurales que conforman el diseño curricular. El plan posibilita la formación de talento humano cuya praxis apunta a la transformación cuali-cuantitativa, de la situación de salud bucal de la población. Reafirma el modelo educativo docencia-servicio-investigación e inserta conceptos como la bioética, la transculturalidad, la epidisciplinariedad y el uso de lenguas autóctonas de la región y el país. Finalmente, integra la teoría y la práctica en el marco de la estrategia de la atención primaria en salud.