Papers by LUIS RAUL NEIRA CONTRERAS
Metals
The formation and hydrogen sorption properties of the NaMgH3 perovskite/type hydride have been ex... more The formation and hydrogen sorption properties of the NaMgH3 perovskite/type hydride have been examined. Samples were mechanically ball milled under argon for 2, 5 and 15 h; then characterized by X-ray diffraction (XRD), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) coupled with a mass spectrometer (MS). Lattice parameters and cell volume of the main NaMgH3 phase increase as a function of milling. Dehydrogenation proceeded in two-step reactions for the NaMgH3. The maximum amount of released hydrogen was achieved for the 2 h milled NaMgH3 hydride accounting for 5.8 wt.% of H2 from 287 °C to 408 °C. Decomposed NaMgH3 samples were reversibly hydrogenated under 10 bar H2 at ~200 °C.
Materials
The memristor is the fourth fundamental element in the electronic circuit field, whose memory and... more The memristor is the fourth fundamental element in the electronic circuit field, whose memory and resistance properties make it unique. Although there are no electronic solutions based on the memristor, interest in application development has increased significantly. Nevertheless, there are only numerical Matlab or Spice models that can be used for simulating memristor systems, and designing is limited to using memristor emulators only. A memristor emulator is an electronic circuit that mimics a memristor. In this way, a research approach is to build discrete-component emulators of memristors for its study without using the actual models. In this work, two reconfigurable hardware architectures have been proposed for use in the prototyping of a non-linearity memristor emulator: the FPAA (Field Programing Analog Arrays) and the FPGA (Field Programming Gate Array). The easy programming and reprogramming of the first architecture and the performance, high area density, and parallelism o...
Enseñanza de las Ciencias. Revista de investigación y experiencias didácticas, 2008
A partir del trabajo de Sfard en relación con las fases de interiorización, condensación y cosifi... more A partir del trabajo de Sfard en relación con las fases de interiorización, condensación y cosificación para explicar los procesos cognitivos referidos al aprendizaje de las matemáticas, realizamos una propuesta de modelo interpretativo del desarrollo profesional. A continuación, analizamos sus características aplicándolo al caso de una maestra participante en un entorno colaborativo de desarrollo profesional, evidenciando de este modo las potencialidades del modelo.
Revista Latinoamericana De Psicologia, 2011
Studies using Event-Related Potentials have shown the existence of a component called Feedback Er... more Studies using Event-Related Potentials have shown the existence of a component called Feedback Error-Related Negativity (fERN). This component has been characterized as a negative deflection which responds differentially to profits and losses in terms of expected and unexpected outcomes. Thus, while some studies have defined the idea of "expected outcome" as the probability to win vs. to lose, others have defined it as the expected size of rewards. How these alternative interpretations of "expected outcome" affect the fERN's research, and the effects of their interaction under a specific model of "expected value" has not been properly assessed. This work contextualizes the general study of neural mechanisms involved in decisionmaking processes, putting the fERN studies in context; besides, it reviews the two main approaches to its research; and finally, it explores the possibilities to further expand the fERN studies, in the context of the transdisc...
ArXiv, 2018
In this work, we present a multimodal system for active robot-object interaction using laser-base... more In this work, we present a multimodal system for active robot-object interaction using laser-based SLAM, RGBD images, and contact sensors. In the object manipulation task, the robot adjusts its initial pose with respect to obstacles and target objects through RGBD data so it can perform object grasping in different configuration spaces while avoiding collisions, and updates the information related to the last steps of the manipulation process using the contact sensors in its hand. We perform a series of experiment to evaluate the performance of the proposed system following the the RoboCup2018 international competition regulations. We compare our approach with a number of baselines, namely a no-feedback method and visual-only and tactile-only feedback methods, where our proposed visual-and-tactile feedback method performs best.
Although the skills required to solve isolated robotics problems are reaching amazing performance... more Although the skills required to solve isolated robotics problems are reaching amazing performances recently, we propose the evaluation of such individual solutions in fully integrated robot systems tested in real daily situations like those presented at international robotics competitions. The simulation Domestic Standard Platform League (sDSPL), which utilizes the HSR simulator developed for the World Robot Summit, surges from the necessity to standardise and spread the research on Domestic Service Robots where a series of solutions can be tested to solve a general-purpose task in a standard domestic environment; this approach has been proven successful at several international competitions, namely, the RoboCup Japan Open, the Mexican Tournament of Robotics, and the RoboCup 2021.**This work was accepted to The 39th Annual Conference of the Robotics Society of Japan.
Géotechnique, 2019
The fall-cone test is one of the most popular methods used to characterise fine-grained soils. Tr... more The fall-cone test is one of the most popular methods used to characterise fine-grained soils. Traditionally, the fall-cone has been used to determine the liquid limit. However, the undrained shear strength of a given soil can be related to the penetration depth based on Hansbo's cone factor K. Specifically for the 30° cone, a wide number of different K values are reported in the literature, ranging from 0·5 to 1·33. It has been consistently argued that the cone surface roughness is one of the main reasons for the divergence. In the first part of this paper, four different cone surfaces were tested under similar conditions with three different soils; the experimental evidence shows that the cone surface roughness does not have a major effect on the fall-cone penetration. Instead, different shear rates during calibration procedures are mainly responsible for diverging K values. In the second part of the paper, experimental evidence from this work and that of several other authors...
Journal of Rock Mechanics and Geotechnical Engineering, 2019
A Bayesian approach is proposed for the inference of the geotechnical parameters used in slope de... more A Bayesian approach is proposed for the inference of the geotechnical parameters used in slope design. The methodology involves the construction of posterior probability distributions that combine prior information on the parameter values with typical data from laboratory tests and site investigations used in design. The posterior distributions are often complex, multidimensional functions whose analysis requires the use of Markov chain Monte Carlo (MCMC) methods. These procedures are used to draw representative samples of the parameters investigated, providing information on their best estimate values, variability and correlations. The paper describes the methodology to define the posterior distributions of the input parameters for slope design and the use of these results for evaluation of the reliability of a slope with the first order reliability method (FORM). The reliability analysis corresponds to a forward stability analysis of the slope where the factor of safety (FS) is calculated with a surrogate model from the more likely values of the input parameters. The Bayesian model is also used to update the estimation of the input parameters based on the back analysis of slope failure. In this case, the condition FS ¼ 1 is treated as a data point that is compared with the model prediction of FS. The analysis requires a sufficient number of observations of failure to outbalance the effect of the initial input parameters. The parameters are updated according to their uncertainty, which is determined by the amount of data supporting them. The methodology is illustrated with an example of a rock slope characterised with a Hoek-Brown rock mass strength. The example is used to highlight the advantages of using Bayesian methods for the slope reliability analysis and to show the effects of data support on the results of the updating process from back analysis of failure.
Journal of Rock Mechanics and Geotechnical Engineering, 2018
One of the main difficulties in the geotechnical design process lies in dealing with uncertainty.... more One of the main difficulties in the geotechnical design process lies in dealing with uncertainty. Uncertainty is associated with natural variation of properties, and the imprecision and unpredictability caused by insufficient information on parameters or models. Probabilistic methods are normally used to quantify uncertainty. However, the frequentist approach commonly used for this purpose has some drawbacks. First, it lacks a formal framework for incorporating knowledge not represented by data. Second, it has limitations in providing a proper measure of the confidence of parameters inferred from data. The Bayesian approach offers a better framework for treating uncertainty in geotechnical design. The advantages of the Bayesian approach for uncertainty quantification are highlighted in this paper with the Bayesian regression analysis of laboratory test data to infer the intact rock strength parameters σci and mi used in the Hoek-Brown strength criterion. Two case examples are used to illustrate different aspects of the Bayesian methodology and to contrast the approach with a frequentist approach represented by the nonlinear least squares (NLLS) method. The paper discusses the use of a Student's t-distribution versus a normal distribution to handle outliers, the consideration of absolute versus relative residuals, and the comparison of quality of fitting results based on standard errors and Bayes factors. Uncertainty quantification with confidence and prediction intervals of the frequentist approach is compared with that based on scatter plots and bands of fitted envelopes of the Bayesian approach. Finally, the Bayesian method is extended to consider two improvements of the fitting analysis. The first is the case in which the Hoek-Brown parameter, a, is treated as a variable to improve the fitting in the triaxial region. The second is the incorporation of the uncertainty in the estimation of the direct tensile strength from Brazilian test results within the overall evaluation of the intact rock strength.
Revista médica de Chile, 2015
Molecular analysis of sporadic colon cancer Background: In Chile, colorectal cancer (CRC) is ofte... more Molecular analysis of sporadic colon cancer Background: In Chile, colorectal cancer (CRC) is often diagnosed in late stages. Thus, surgical treatment must be complemented with chemotherapy. KRAS mutations and microsatellite instability have been detected in these tumors. However, the response to treatment in patients without KRAS mutations varies and requires a better understanding. Aim: To determine the frequency and distribution of somatic point mutations in KRAS, BRAF and PIK3CA genes and microsatellite instability status (MSI) in patients with colon cancer (CC). Material and Methods: A prospective observational study of patients undergoing surgery for colon cancer. Tumor-derived DNA was analyzed by polymerase chain reaction (PCR) for the most frequent mutations of KRAS, BRAF and PIK3CA. PCR was also used to analyze MSI. Results: Fifty-eight patients with sporadic CC were analyzed, 16 showed KRAS mutations (G12R, G12D, G12V, G13D) and out of the 42 patients that did not show any mutation, 10 had mutations in BRAF (V600E) and PIK3CA (E542K, E545D, E545K, Q546E, H1047R). BRAF mutations alone or in combination with PIK3CA mutations were observed in 27% of high MSI tumors and in 2% of tumors without instability (p < 0.049). A higher percentage of high MSI tumors were located in the right colon (p < 0.001), and showed BRAF mutation (p < 0.020). Conclusions: The highest percentage of high MSI and BRAF mutations was observed in the right colon. Therefore, this study suggests the presence of different molecular features between right and left colon tumors that should be considered when defining the therapeutic management.
ABSTRACT Studies using Event-Related Potentials have shown the existence of a component called Fe... more ABSTRACT Studies using Event-Related Potentials have shown the existence of a component called Feedback Error-Related Negativity (fERN). This component has been characterized as a negative deflection which responds differentially to profits and losses in terms of expected and unexpected outcomes. Thus, while some studies have defined the idea of “expected outcome” as the probability to win vs. to lose, others have defined it as the expected size of rewards. How these alternative interpretations of “expected outcome” affect the fERN’s research, and the effects of their interaction under a specific model of “expected value” has not been properly assessed. This work contextualizes the general study of neural mechanisms involved in decisionmaking processes, putting the fERN studies in context; besides, it reviews the two main approaches to its research; and finally, it explores the possibilities to further expand the fERN studies, in the context of the transdisciplinary rising field of neuroeconomics.
Revista médica de Chile, 2012
Lynch syndrome: selection of families by microsatellite instability and immunohistochemistry Back... more Lynch syndrome: selection of families by microsatellite instability and immunohistochemistry Background: Selection of patients with Lynch Syndrome (LS) for a genetic study involves the application of clinical criteria. To increase the rate of identification of mutations, the use of molecular studies as Microsatellite Instability (MSI) and Immunohistochemistry (IHC) in the tumor has been proposed. Aim: To demonstrate the usefulness of MSI and IHC in the detection of mutations in patients with LS. Material and Methods: From our Familial Colorectal Cancer Registry, families suspected of LS were selected according to Amsterdam or Bethesda clinical criteria. Screening of germline mutations of MLH1, MSH2 and MSH6 genes was performed. In addition, analysis of MSI and IHC were performed in colorectal tumors. Results: A total of 35 families were studied (19 met Amsterdam and 16 met Bethesda criteria). Twenty one families harbored a germline alteration in MLH1, MSH2 or MSH6 (18 Amsterdam and 3 Bethesda). In these families, eighteen different alterations were found, 15 of which were mutations and 3 corresponded to variants of uncertain pathogenicity. On the other hand, 80% of the tumors showed positive microsatellite instability (27 MSI-high and 1 MSI-low), and immunohistochemical testing showed that 77% of tumors had the loss of a protein. Correlation between results of tumor molecular studies and the finding of germline nucleotide change showed that IHC and MSI predicted mutations in 81 and 100% of patients, respectively. Conclusions: MSI and IHC can efficiently select patients with a high probability of carrying a mutation in DNA repair genes.
Revista médica de Chile, 2012
A screening program for colorectal cancer in Chilean subjects aged fi fty years or more Backgroun... more A screening program for colorectal cancer in Chilean subjects aged fi fty years or more Background: Mortality from colorectal cancer (CCR) in Chile has nearly doubled over the past 15 years. International studies have shown that CCR screening programs based on fecal occult blood test (FOBT) reduce CCR mortality. Aim: To analyze the results from a CCR screening model in people over 50 years. Material and Methods: Between 2007 and 2009, a prospective multicenter study was performed in seven major Chilean cities. FOBT using an immunological method, was measured in asymptomatic subjects aged 50 years or more, without risk factors. In patients with a positive FOBT, with symptoms or with family risk factors, a colonoscopy was indicated. Results: A total of 6348 subjects were assessed, FOBT was performed in 4938 of them, with a compliance of 77%. The result was positive in 9.6%. A total of 2359 colonoscopies were ordered, with an overall compliance of 50.1%. Of the 1184 colonoscopies performed, adenomas and high risk adenomas were found in 304 (26%) and 75 (6%) patients, respectively. Thirteen patients were diagnosed with stage I and II CCR. Three of these lesions were excised endoscopically and 10 surgically. The detection rate of polyps, high risk adenomas and cancer was 75, 12 and 2 per 1000 screened individuals, respectively. Conclusions: This program allowed the early detection of an important number of high risk colon lesions, and all patients with CCR were diagnosed at early stages.
Bolema: Boletim de Educação Matemática, 2012
Desde la educación matemática, la formación inicial del maestro debe promover la adquisición de c... more Desde la educación matemática, la formación inicial del maestro debe promover la adquisición de competencias en la enseñanza y aprendizaje de las matemáticas, asumiendo adquiridas, al menos en gran parte, las relativas a la disciplina. Este objetivo se ve mermado por las numerosas y graves lagunas en conocimientos puramente matemáticos de los estudiantes para maestro que acceden a ella, que les impide implicarse en razonamientos didácticos específicos. En este artículo describimos las competencias numéricas deseables en los estudiantes para Maestro y, a través de un estudio exploratorio con alumnos de la Universidad de Huelva, indagamos sobre el grado de adquisición de algunas de ellas.
Bolema: Boletim de Educação Matemática, 2014
Este estudio trata de conocer la importancia que tienen las oportunidades de aprendizaje (OTL) qu... more Este estudio trata de conocer la importancia que tienen las oportunidades de aprendizaje (OTL) que ofrece el profesor en su aula a la hora de facilitar la adquisición de las competencias matemáticas de sus estudiantes (CM). Se presenta la parte empírica de una investigación, que ha consistido en el estudio de dos casos particulares (en España y Armenia), y documentamos los resultados obtenidos a la luz de un modelo teórico OTL-CM, construido de forma emergente en el proceso de análisis de los datos. Los resultados de nuestra investigación han constatado que las escasas OTL que promueven el aprendizaje significativo de las matemáticas limitan tanto la adquisición de los conocimientos y destrezas matemáticas básicas, como la capacidad de aplicarlos en situaciones de la vida real.
World Journal of Surgery, 1997
One of the alternatives for the repair of large incisional hernias is the use of a prosthetic mat... more One of the alternatives for the repair of large incisional hernias is the use of a prosthetic material. The present retrospective study relates the experience acquired for treatment of large incisional hernias (hernial orifice &amp;amp;amp;amp;gt; 10 cm) with ePTFE prostheses. Thirty-eight massive incisional hernias were repaired using ePTFE 1 mm thick Soft Tissue Patches. Twenty-four patients received a prosthetic patch of 10 x 15 cm, 13 a patch of 15 x 20 cm, and 1 a patch of 20 x 30 cm. In 30 cases the ePTFE was sutured to the recipient tissues with a double row of polypropylene stitches. For the first eight interventions the ePTFE was secured using a single row of polypropylene sutures. Pathologic studies of biopsies from patients who had undergone surgical reintervention at 40 days, 12 months, and 48 months, respectively, were done using light microscopy, scanning electron microscopy, and immunohistochemistry with human antimacrophage antibodies KP-1. The follow-up period for all patients was between 18 and 72 months. There was no perioperative mortality. No infection or rejection of prostheses was recorded. Seroma was present in four patients. Computed tomography was performed for evaluation purposes on 10 randomly selected patients (mean postoperative delay 1-4 years) and showed the ePTFE encapsulated by newly formed tissue. One of the patients suffered from mechanical intestinal obstruction 40 days after implant and suffered a recurrence a year later. Three recurrences at the patch-recipient tissue interface where the ePTFE had been secured with a single row of polypropylene stitches were recorded after 8, 12, and 28 months. At 40 days good integration of the biomaterial was observed in the newly formed tissue. On both sides of the implant an accumulation of four to six strata of cells was appreciable. Some of them were labeled with KP-1. Cell infiltration of the prosthesis was restricted to the most exterior third of the patch. There was no colonization at the patch-recipient tissue interface. At 12 and 28 months the cell barrier had almost disappeared. KP-1-labeled macrophages were scarce. Scanning electron microscopy revealed a well defined peritoneum. It may be concluded that: (1) a double suture row is recommended to secure the prosthesis; (2) ePTFE provides an adequate substrate for the formation of scar tissue; and (3) the macrophage response induced by the ePTFE decreases with time.
Transplantation Proceedings, 2008
Alemtuzumab (ALT), a humanized monoclonal anti-CD52 antibody, was introduced in solid organ trans... more Alemtuzumab (ALT), a humanized monoclonal anti-CD52 antibody, was introduced in solid organ transplantation as an induction agent. ALT associated with anticalcineurins has provided a low incidence of acute rejection episodes (ARE) and potential tolerogenic properties. We analyzed the clinical outcomes and effects on peripheral Treg of renal transplant recipients treated with ALT. Six-month data on kidney alone or kidney combined with pancreas or liver patients treated with ALT and tacrolimus (TAC) in standard doses were compared with those on renal transplant recipients of similar demography who were not treated with ALT. We evaluated patient and graft survivals, ARE incidence, hematological parameters, renal function, adverse events, and CD4ϩCD25ϩFoxP3ϩ T cells in peripheral blood. Demographics of recipients, donors, and transplants were similar in both groups. Mean HLA mismatch was slightly greater among ALT-treated patients (3.5 vs 2.5). No combined transplantation was performed in the ALT-untreated group. Patient and graft survivals were 100% without rejection or serious infections in both groups. ALT-treated recipients showed anemia and leukopenia in 3 patients as well as severe lymphopenia in 5 recipients, who partially recovered on day 90. Final mean plasma creatinine was 1.4 mg/dL, while calculated creatinine clearance was approximately 65 mL/min in both groups. Mean Treg cell percentage was higher among ALT-treated recipients than the comparative group or healthy controls (P Ͻ .05). In conclusion, renal transplantation results obtained using ALT with rigorous immunosuppressive therapy were excellent; serious adverse events and acute rejection were absent. The effect of the increased proportion of Treg cells must be evaluated with longer observation.
The Engineering Economist, 1975
Page 1. Volume 20 - Number 4 Expected Present Worths ofCash Flows Under Uncertain Timing Donovan ... more Page 1. Volume 20 - Number 4 Expected Present Worths ofCash Flows Under Uncertain Timing Donovan Young Luis E. Contreras Georgia Institute of Technology INTRODUCTION 257 Maximization of expected present worth is a widely' accepted decision principle ...
The American Naturalist, 1981
NOTES AND COMMENTS 597 SAXICOLOUS LICHEN COMMUNITIES: NONEQUILIBRIUM SYSTEMS? The theory of islan... more NOTES AND COMMENTS 597 SAXICOLOUS LICHEN COMMUNITIES: NONEQUILIBRIUM SYSTEMS? The theory of island biogeography, originally formulated by MacArthur and Wilson (1967), hypothesizes that the number of species of a given taxonomic group of organisms ...
Pediatric Nephrology, 2011
This prospective, comparative trial investigated the impact on mean change in height standard dev... more This prospective, comparative trial investigated the impact on mean change in height standard deviation score (SDS), acute rejection rate, and renal function of early steroid withdrawal in 96 recipients with 5 years of follow-up. Recipients under basiliximab induction and steroid withdrawal (SW: TAC/MMF; n = 55) were compared with a matched steroid control group (SC: TAC/MMF/STEROID, n = 41). SW received steroids until Day 6, SC decreased to 10 mg/m(2) within 2 months post-transplant. Five years after SW, the longitudinal growth (SDS) gain was 1.4 ± 0.4 vs. 1.1 ± 0.3 for SC group (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.02). Height benefits in prepubertal and pubertal status in both groups were demonstrated in the delta growth trends (mixed model; p…
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Papers by LUIS RAUL NEIRA CONTRERAS