Santiago de los Caballeros, Dominican Republic

Pontifical Catholic University Madre y Maestra
Santiago de los Caballeros, Dominican Republic
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Lalonde L.F.,Canadian Food Inspection Agency | Reyes J.,Pontifical Catholic University Madre y Maestra | Gajadhar A.A.,Canadian Food Inspection Agency
American Journal of Tropical Medicine and Hygiene | Year: 2013

A quantitative polymerase chain reaction assay with melt curve analysis (qPCR-MCA) was applied for the detection of protozoan oocysts in 501 human fecal samples collected in Dominican Republic. Samples were subjected to qPCR using universal coccidia primers targeting 18S rDNA to detect oocysts followed by MCA to identify oocyst species based on amplicon melting temperature. Putative positive samples were also tested by conventional PCR and microscopy. Cystoisospora belli ( ×3), Cryptosporidium parvum ( ×3), Cryptosporidium hominis ( ×5), Cryptosporidium meleagridis ( ×1), Cryptosporidium canis ( ×1), and Cyclospora cayetanensis ( ×9) were detected by qPCR-MCA and confirmed by sequencing. This assay consistently detected 10 copies of the cloned target fragment and can be considered more efficient and sensitive than microscopy flotation methods for detecting multiple species of oocysts in human feces. The qPCR-MCA is a reliable protozoan oocyst screening assay for use on clinical and environmental samples in public health, food safety and veterinary programs. Copyright © 2013 by The American Society of Tropical Medicine and Hygiene.

Silvestre G.,Pontifical Catholic University Madre y Maestra | Iglesias R.M.,Pontifical Catholic University Madre y Maestra | Silvestre E.,Pontifical Catholic University Madre y Maestra
Aphasiology | Year: 2017

Background: Although neuropsychology is a well-established discipline worldwide, in the Dominican Republic (DR), its practice is relatively new. Aims: This research was conducted with the aim of adapting and standardising the 2005, 60-item version of the Boston Naming Test (BNT) in the DR, taking into consideration the influence of gender, educational level and age. Methods & Procedures: The sample consisted of 239 Spanish-speaking, healthy community-dwelling Dominicans between 16 and 80 years of age from each of the country’s major provinces. Outcomes & Results: Results indicate that, of the demographic variables studied, the educational level alone influences performance on the naming test. Conclusions: We recommend a change in the presentation order of the original BNT items to respond to the intended increase in difficulty. The use of these norms will facilitate interpretation of the results not only for Dominicans in the DR but also for first-generation Dominicans who live in other countries like the United States, Canada, and Spain, where there are sizeable Dominican communities, helping to adequately classify performances as normal or pathological. © 2017 Informa UK Limited, trading as Taylor & Francis Group

Reyes-Jaquez B.,Pontifical Catholic University Madre y Maestra | Echols C.H.,University of Texas at Austin
Journal of Cognition and Development | Year: 2016

In 2 studies, we examined how 5-­year-­olds weigh similarity against other factors in deciding from whom to learn. Specifically, we examined the factors of history of and reasons for inaccuracy in Experiment 1 (n = 64) and of competence and authority in Experiment 2 (n = 32). In the 1st phase of Experiments 1 and 2, children’s social biases were tested: 5-year-olds met both a similar informant (SI) and a dissimilar informant (DI). These informants were puppets (Experiment 1) or human teachers (Experiment 2). Children could select either informant as a source of object names. Across experiments children systematically preferred learning from the SI over DI. In the 2nd phase of Experiment 1, both informants first provided accurate information and then 1 of them became inaccurate during an event that clearly explained (being blindfolded) or did not explain (wearing a scarf) the inaccuracy. For half the children, the SI was accurate and the DI was inaccurate. Only after inaccuracy events that were causally unclear did children showcase similarity biases in their subsequent learning preferences. Experiment 2 showed that identifying a DI as a teacher (a profession associated with positive attributes) failed to counter children’s similarity bias. These findings provide important insights on contextual factors that contribute to children’s favoring of socially meaningful others. Copyright © 2016 Taylor & Francis Group, LLC

Guo Y.,Purdue University | Efe M.,Purdue University | Moscoso W.,Pontifical Catholic University Madre y Maestra | Moscoso W.,Purdue University | And 3 more authors.
Scripta Materialia | Year: 2012

The deformation field in large-strain extrusion machining, a constrained chip formation process, is characterized using high-speed imaging and particle image velocimetry. The field is shown to be controllable and narrowly confined, with attributes ranging from conventional deformation processing to severe plastic deformation. Implications for deformation processing of sheets, engineering of microstructures in bulk forms and on machined surfaces, and study of large-strain deformation phenomena in metal alloys are highlighted. © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Efe M.,Purdue University | Moscoso W.,Pontifical Catholic University Madre y Maestra | Moscoso W.,Purdue University | Trumble K.P.,Purdue University | And 2 more authors.
Acta Materialia | Year: 2012

An analysis of the mechanics of large strain extrusion machining (LSEM), a constrained chip formation process, is presented for deformation processing of bulk alloys. The deformation field is shown to be narrowly confined and controllable, with attributes ranging from conventional deformation processing to severe plastic deformation. Controllable deformation parameters include strain/strain rate, hydrostatic pressure, temperature and deformation path. These attributes are highlighted in deformation processing of Mg AZ31B, an alloy of commercial significance but noted for its poor workability, into sheet and foil forms. Noteworthy features of the processing are suppression of segmentation, realization of a range of strains and deformation rates, engineering of microstructures ranging from conventional to ultrafine grained, and creation of sheet/foil from the bulk in a single step of deformation without pre-heating. Guidelines for realizing specific sheet attributes, and scalability of LSEM for production are analyzed and discussed. © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Sagapuram D.,Purdue University | Efe M.,Purdue University | Moscoso W.,Pontifical Catholic University Madre y Maestra | Chandrasekar S.,Purdue University | Trumble K.P.,Purdue University
Acta Materialia | Year: 2013

Constrained chip (sheet) formation by large strain extrusion machining is used to impose effective strains of ∼1 in Mg alloy AZ31B sheet in a single step of deformation. High-speed image analysis shows the deformation underlying sheet formation to be simple shear that is confined to a narrow zone. This confinement of the deformation limits the need for pre-heating of the workpiece to realize continuous sheet forms. Tilted-basal textures, wherein the basal poles are inclined from the sheet surface normal, are achieved by this processing. These textures are quite different from those prevalent in rolled sheet. By controlling the strain path, the basal pole inclination could be varied in the range 32-53. The primary texture component is the B-fiber, indicating basal slip to be the main deformation mode over the temperature range 165-400 C. An additional C2-fiber component appears above 250 C due to the activation of pyramidal 〈c+a〉 slip. In conjunction with these textures, microstructures ranging from ultrafine-grained (∼200 nm) to fine-grained (∼2 μm) could be obtained by controlling the deformation temperature. Implications of the results for production of Mg sheet are discussed. © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Stauffer B.L.,Aurora University | Stauffer B.L.,Denver Health and Hospital Authority | Russell G.,Pontifical Catholic University Madre y Maestra | Nunley K.,Aurora University | And 2 more authors.
Journal of Molecular and Cellular Cardiology | Year: 2013

miRNAs are short regulatory RNAs that can regulate gene expression through interacting with the 3'UTR of target mRNAs. Although the role of miRNAs has been extensively studied in adult human and animal models of heart disease, nothing is known about their expression in pediatric heart failure patients. Different than adults with heart failure, pediatric patients respond well to phosphodiesterase inhibitor (PDEi) treatment, which is safe in the outpatient setting, results in fewer heart failure emergency department visits, fewer cardiac hospital admissions and improved NYHA classification. We have recently shown that pediatric heart failure patients display a unique molecular profile that is different from adults with heart failure. In this study we show for the first time that pediatric heart failure patients display a unique miRNA profile, and that expression of some miRNAs correlate with response to PDEi treatment. Moreover, we show that expression of Smad4, a potential target for PDEi-regulated miRNAs, is normalized in PDEi-treated patients. Since miRNAs may be used as therapy for human heart failure, our results underscore the importance of defining the molecular characteristics of pediatric heart failure patients, so age-appropriate therapy can be designed for this population. © 2013 Elsevier Ltd.

Bueno-Lopez S.W.,Pontifical Catholic University Madre y Maestra | Bevilacqua E.,New York University
IForest | Year: 2012

The ability to predict cumulative bole volume to any predefined upper stem diameter on a standing tree is essential for estimating current inventory levels and making informed decisions regarding the management of forest resources. Several types of mathematical models have been developed to predict cumulative bole volume, requiring only the collection of low cost data but high accuracy tree measurements. This paper reports on the comparison of a variableexponent taper model and a volume-ratio model for estimating inside-bark cumulative bole volume to three predefined upper stem diameters using stem analysis data Pinus occidentalis trees in La Sierra, Dominican Republic. Each sampled tree was measured at multiple points on the bole, making observations spatially correlated within the tree. Inference problems due to autocorrelation were addressed by using a nonlinear mixed-effects model fitted by restricted maximum likelihood (REML) and including two random parameter coefficients at tree level in each of the two models tested. Using an independent validation data set, the variable-exponent taper model with two random parameters demonstrated better predictive ability as compared to the volume-ratio model when estimating cumulative bole volume to the three predefined upper stem diameters. The taper model allows flexible volume estimation for the population average as well for specific trees. © iForest - Biogeosciences and Forestry.

Hernandez T.,Organic Waste Management | Garcia E.,Pontifical Catholic University Madre y Maestra | Garcia C.,Organic Waste Management
Soil Biology and Biochemistry | Year: 2015

This work evaluates the mid-term impact of the addition of large amounts of an organic amendment on the recovery of the physical, chemical and, particularly, the microbiological properties of a marginal semiarid degraded soil and on increasing the soil organic C pool. In order to perform this study, a semiarid degraded soil was treated with composted urban waste at doses equivalent to the addition of 1% (S+CCD1) and 3% (S+CCD2) of organic C (Corg). Changes in soil characteristics in the amended soils were evaluated with respect to a control soil without organic amendment for a period of 5 years after the organic amendment was applied. A spontaneous vegetal cover developed on both amended and unamended soils 3-4 months after the organic amendments were added, yet the level of vegetal biodiversity was lower in the amended plots. Compost-amended soils showed higher concentrations of Corg, water-soluble C and water-soluble carbohydrates than the control soil throughout the experimental period. Furthermore, all of these C fractions were significantly higher (p≤0.05) in S+CCD2 than in S+CCD1 and the control soil.However, compost addition also increased soil electrical conductivity and nitrate content, particularly at the higher dose. Likewise, compost addition produced a 4- to 10-fold increase in soil heavy metal concentrations, although the levels of heavy metal were under the limits allowed in soils. Five years after the organic amendment was added, the soil water holding capacity, stable aggregate percentage, porosity and nutrient and humic substance and humic acid content were greater in amended soils than in control soil, and the higher dose produced greater increases than the lower dose. Soils receiving the highest dose of compost also showed the highest values of basal respiration, dehydrogenase activity and β-glucosidase and phosphatase activity, as well as a greater abundance of total PLFAs, bacterial and fungal PLFAs, and saturated and monounsaturated fatty acids. A greater level of functional diversity was also observed in amended soils, particularly in the soil receiving the higher dose of compost. It can be concluded that the addition of high doses of compost can be a suitable strategy for restoring semiarid degraded soils and for fixing C in these soils, provided that the organic material is of high quality and has a low concentration of heavy metals. © 2015 Elsevier Ltd.

Provided herein are carbon nanotubes conformally coated with diamond nanocrystals or silicon carbide, or both, methods of their preparation, methods of their use and compositions and materials comprising the conformally coated carbon nanotubes.

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