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Centrolene savagei
Number of Pages: 11Geological SciencesIntegrative Biolog
Molecular phylogenetics of the Pristimantis lacrimosus species group (Anura: Craugastoridae) with the description of a new species from Colombia
The Pristimantis lacrimosus species group, with 24 species distributed in the Neotropics, is a group of arboreal frogs commonly inhabiting bromeliads. Previous studies have claimed the group to be monophyletic but few species have been included in phylogenetic analyses. In this paper, we included five additional species from the northern Andes in Colombia and tested the monophyly of this phenetic group using genetic data under a Bayesian approach. Our results show that the P. lacrimosus group represents two distant and unrelated clades. Clade “A” is endemic to Colombia while Clade “B” encompasses species distributed in Central America, Ecuador and Peru. For the first time, we reveal the phylogenetic position of P. boulengeri and a new species is described. The new taxon is most closely related to P. brevifrons from southwestern Colombia with a genetic distance of 4.3% for 16S and 10.6% for COI. Our results suggest, one more time, that morphological similarity among species in the most diverse vertebrate genus not necessarily agree with its evolutionary history and that more effort in alpha taxonomy needs to be done in order to understand the tremendous radiation of this lineage in the Neotropics
Validating a High-performance Liquid Chromatography method for the quantification of gibberellic acid in germinating maize seeds
Gibberellic acid is a phytohormone that triggers the germination of seeds
in a state of dormancy. Through the quantification of this hormone, the
physiological condition of seeds of economic importance can be studded.
In this work we validated a High-Performance Liquid Chromatography
method to quantify gibberellic acid in germinated maize (Zea mays L.)
seeds. Chromatographic conditions included the use of a C-18 reversed-phase
column, acetonitrile-formic acid (1:9 %) as the mobile phase, flow of 0.5 mL
min−1
, and detection at 195 nm. We evaluated our method for seven analytical
parameters. The method was linear for gibberellic acid concentrations from
1.0 mg·kg−1
to 50.0 mg·kg−1
. The method’s limits were 0.3 mg·kg−1
and
1.0 mg·kg−1
for detection and quantification, respectively. The method was
highly precise; we obtained variable but low relative standard deviations
(2.62 % - 12.66 %) for the studied gibberellic acid concentrations. We assessed
accuracy through recovery percentages, ranging from 52.85 % - 63.68 %, for
three gibberellic acid concentrations. We conclude that our analytical method
can be used to measure gibberellic acid during the early stages of maize
germination. In addition, the method could be used for the analysis of other
types of plant matrices
Comparación de la distribución de tamaño de bolas de alúmina en dos unidades de molienda de cemento blanco utilizando la función swebrec
Micromechanical Properties of Injection-Molded Starch–Wood Particle Composites
The micromechanical properties of injection molded starch–wood particle composites were investigated as a function of particle content and humidity conditions.
The composite materials were characterized by scanning electron microscopy and X-ray diffraction methods. The microhardness
of the composites was shown to increase notably with the concentration of the wood particles. In addition,creep behavior under the indenter and temperature dependence
were evaluated in terms of the independent contribution of the starch matrix and the wood microparticles to the hardness value. The influence of drying time on the density
and weight uptake of the injection-molded composites was highlighted. The results revealed the role of the mechanism of water evaporation, showing that the dependence of water uptake and temperature was greater for the starch–wood composites than for the pure starch sample. Experiments performed during the drying process at 70°C indicated that
the wood in the starch composites did not prevent water loss from the samples.Peer reviewe
Sensitive Periods for Psychosocial Risk in Childhood and Adolescence and Cardiometabolic Outcomes in Young Adulthood
Greater psychosocial risk in childhood and adolescence predicts poorer cardiometabolic outcomes in adulthood. We assessed whether the timing of psychosocial risk from infancy through adolescence predicts cardiometabolic outcomes in young adulthood. Young adults and their mothers participated in a longitudinal study beginning in infancy in Santiago, Chile (N = 1040). At infancy, 5 years, 10 years, and adolescence, mothers reported on depressive symptoms, stressful experiences, support for child development in the home, father absence, parental education, and socioeconomic status (SES) to create a psychosocial risk composite at each time point. Young adults (52.1% female; 21–27 years) provided fasting serum samples and participated in anthropometric and blood pressure (BP) assessments, including a dualenergy X-ray absorptiometry (DXA) scan for measuring body fat. Greater infant psychosocial risk was associated with a greater young adult metabolic syndrome score (β = 0.07, 95% confidence intervals (CI): 0.01 to 0.13, p = 0.02), a higher body mass index and waist circumference composite (β = 0.08, 95% CI: 0.03 to 0.13, p = 0.002), and a higher body fat (DXA) composite (β = 0.07, 95% CI: 0.01 to 0.12, p = 0.02). No psychosocial risk measure from any time point was associated with BP. Infant psychosocial risk predicted cardiometabolic outcomes in young adulthood better than psychosocial risk at 5 years, 10 years, or adolescence, mean of psychosocial risk from infancy through adolescence, and maximum of psychosocial risk at any one time. Consistent with the Developmental Origins of Health and Disease model, findings suggest that infancy is a sensitive period for psychosocial risk leading to poorer cardiometabolic outcomes in young adulthood
Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).
Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and ≥1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (n = 5069) or prospectively (n = 5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (≤6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; p = 0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)
Estudio sobre la distribución de tamaño de bola de alúmina en molienda de cemento blanco
IER, JLP, AL and MRF thank to Institución Universitaria Pascual Bravo for the financial support within the research project entitled: “Estudio espectral y de la respuesta óptica de sistemas de pocas partículas confinadas en nanoestructuras semiconductoras cuasi bidimensionales” with grant number IN201907
A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)
Meeting abstrac
Respuesta fisiológica y productiva de novillos engordados con un sistema de enfriamiento a espacio abierto en un clima árido y seco
Evaluation of the effects of an open space cooling system on weight gain, respiration rate and serum thyroid hormone (T3 and T4) levels in feedlot steers was done using 60 Holstein steers (344 kg) allotted randomly in two treatments: a control with only shade in the corral (n=30), and a cooling with an open space cooling system (n=30). Daily maximum temperature-humidity index (THI) ranged from 82 to 88 during the 12-week study period. The open space cooling system consisted of a fan with 2.4 m diameter blade that displaced 1,416 m3 of air per minute and had a 90º oscillation range, and sprinklers. The fan was installed at 8 m distance on the south side of the shade. Water discharge was 12 L per minute over a 7 h period. Body weight and thyroid hormone levels were measured every two weeks and respiration rate twice a week (1400). Data were analyzed by repeated measures, including initial weight as a covariate. Daily weight gain was different (PCon objeto de evaluar el efecto de un sistema de enfriamiento a espacio abierto sobre la ganancia de peso, frecuencia de respiración y niveles sanguíneos de triiodotironina (T3) y tiroxina (T4) durante el verano, 60 novillos Holstein fueron asignados aleatoriamente a un grupo testigo con únicamente sombra y un segundo grupo con sombra, más enfriamiento. Durante el experimento se registró un Índice de temperatura-humedad máximo que oscilo entre 82 a 88. El sistema de enfriamiento colocado a 8 m a partir de la sombra, consistió de una hélice de 2.4 m de diámetro produciendo 1,416 m3/min de aire con una rotación de 90° y un flujo de agua de 12 L/min. El peso corporal y los niveles de hormonas fueron registrados cada dos semanas, mientras la frecuencia de respiración (1400) en dos ocasiones por semana. Los datos fueron analizados con un diseño de mediciones repetidas, incluyendo el peso inicial como covariable. La ganancia de peso fue mayor (
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