Colecciones Institucionales

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Browsing Colecciones Institucionales by browse.metadata.fuente "ORCID"

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    11β-hydroxysteroid dehydrogenase type 2 polymorphisms and activity in a Chilean essential hypertensive and normotensive cohort.
    (2012) Campino, Carmen; Quinteros, Hector; Owen, Gareth I.; Carvajal, Cristian A.; Morales, Mauricio; Olivieri, Oliviero; Guidi, Giancesare; Faccini, Giovanni; Pasini, Francesco; Baudrand, Rene; Padilla, Oslando; Valdivia, Carolina; Thichauer, Juan; Lagos, Carlos F.; Kalergis, Alexis M.; Fardella, Carlos E.
    BACKGROUND: 11β-hydroxysteroid dehydrogenase type 2 enzyme (11β-HSD2) inactivates cortisol (F) to cortisone (E); its impairment is associated with hypertension. We reported that 15.7% of the Chilean essential hypertensives possessed a high F/E ratio suggesting a partial deficit in 11β-HSD2 activity. It has been reported that the G534A(Glu178/Glu) polymorphism in the HSD11B2 gene is associated with hypertension. Investigate the frequency of the G534A polymorphism and its correlation with the glucocorticoid profile in Chilean essential hypertensive and normotensive subjects. METHODS: Essential hypertensive outpatients (n = 232) and normotensive subjects (n = 74) were recruited. A change in the AluI restriction enzyme digest pattern, caused by the presence of the G534A polymorphism, was utilized to screen DNA isolated from leukocytes within the cohort before confirmation by sequencing. Plasma renin activity (PRA), serum aldosterone, F, and E were measured by radioimmunoassay. Urinary tetrahydrocortisol (THF), 5α-tetrahydrocortisol (5α-THF), and tetrahydrocortisone (THE) were measured by gas chromatography-mass spectrometry. RESULTS: G534A polymorphism frequency was similar between hypertensive patients (19 of 232; 8.2%) and normotensive subjects (7 of 74; 9.5%). When categorized by presence or absence of the G534A polymorphism, no significant differences in the serum F/E ratio or other measured biochemical variables were detected. Despite a previous report that the G534A polymorphism is associated with a neighboring C468A (Thr156/Thr) polymorphism, analysis within our cohort showed that only one patient in each group presented with this double polymorphism. CONCLUSIONS: We report the frequency of the G534A polymorphism in the Spanish-Amerindian population. No correlation was detected between this polymorphism and the presence of hypertension and biochemical parameters in this Chilean cohort.
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    25 Hydroxy Vitamin D Level, Bone Health, Vitamin D and Calcium Intake in Chilean Patients with Phenylketonuria and Hyperphenylalaninemias
    (2021) Leiva, Carla; Bravo Jiménez, Paulina; Arias, Carolina; Cabello, Juan; Leal-Witt, María Jesús; Salazar Silva, Florencia; Cornejo, Verónica
    It has been shown that there is a decrease in the concentrations of 25 hydroxyvitamin D (25-OHD) and bone mineral density (BMD) in patients with phenylketonuria (PKU) in their follow-up. Our objective was to determine concentrations of 25-OHD in subjects with PKU and hyperphenylalaninemia (HPA). Transversal analytical study considered three groups: G1-PKU with neonatal diagnosis and formula intake without Phe; G2-HPA, without specific treatment and G3-C control group. Sixteen patients per group (aged 6-23) were included. Levels of 25-OHD, lumbar spine (L2-L4), femur and total BMD, intact parathormone (PTH) and vitamin D (VitD) and calcium intake were calculated. The Kruskal-Wallis statistical test was applied (p-value<0,05). Significant differences were detected in concentrations of 25-OHD between G1-PKU and G2-HPA (38.9 ng/mL; 28 ng/mL, respectively) (NV: >30 ng/mL). G1-PKU had a higher intake of VitD, with differences among groups. There were no significant differences among groups in relation to BMD and intact PTH. In conclusion, G1-PKU under treatment and with good adherence, does not present VitD deficiency and no BMD alterations are observed. In contrast, G2-HPA had a lower intake of VitD and decreased 25-OHD concentrations which could affect the bone architecture in the long term. Further studies on the G2-HPA are suggested.
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    30 years from the Caracas Declaration: the situation of psychiatric hospitals in Latin America and the Caribbean prior, during and after the COVID-19 pandemic
    (2021) Mascayano, Franco; Alvarado, Rubén; Martínez-Viciana, Carmen; Irarázaval, Matías; Durand-Arias, Sol; Freytes, Marcela; Montenegro Cortés, Cristián; Susser, Ezra; Bruni, Andrea
    Latin America and the Caribbean (LAC) recently celebrated 30 years from the Caracas Declaration, which, in 1990, set forth the principles to transition from hospital-based mental health care into community mental health services [1]. Since then, significant efforts have been made to reduce the number of psychiatric hospital beds, increase mental health teams within general hospitals, integrate mental health into primary care, implement outpatient mental health facilities, and encourage the participation of community members in the provision and implementation of mental health care [2]. Nonetheless, progress has been uneven across countries [2]. Many large psychiatric hospitals (PHs) still exist and consume most of the scanty national mental health budgets [3]. Moreover, PH residents in LAC were poor and socially excluded even before the COVID-19 pandemic hit. The COVID-19 pandemic has worsened the living conditions of these people, especially in resource-constrained settings.
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    3D imaging techniques for improved colonoscopy.
    (2014) Durr, Nicholas J.; González, Germán; Parot Fernández, Vicente José
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    3D non-destructive evaluation techniques for wood analysis
    (2014) Paulina Fernández, M.; Tejos Nunez, Cristian Andres; Rojas, G.; Lillo, I.; Guesalaga, A.; Irarrázaval, P.
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    El 98, hoy, en Chile
    (1999) Sagredo Baeza, Rafael
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    A column generation approach to intraday scheduling of chemotherapy patients
    (2023) Lyon Bossay, Gabriel; Cataldo Cornejo, Alejandro; Angulo, Gustavo; Rey, Pablo; Sauré, AntoineLyon Bossay, Gabriel; Cataldo Cornejo, Alejandro; Angulo, Gustavo; Rey, Pablo; Sauré, Antoine
    Chemotherapy scheduling at cancer treatment centres is a complex problem due to high and grow-ing demand, diversity of treatment protocols, limitations on resources and the need to coordinatetreatment session times with laboratory preparation of medication. Over a given planning horizon,treatment centres assign patients first to specific days (interday scheduling) and then to specifictimes within each day (intraday scheduling), the latter process including the definition of medicationpreparation time. This paper addresses the intraday scheduling problem using an integer program-ming model that attempts to schedule all patients assigned to the horizon, and the preparation ofthe medication to be administered, simultaneously. The linear relaxation of the model formulation,which is based on treatment patterns, is solved using column generation. The proposed approachallows for medication preparation on the day of treatment or a previous day subject to time slot avail-ability. A case study is conducted using actual data from a Chilean cancer centre to compare throughsimulationtheschedulesgeneratedbytheproposedapproachandthecentre’smanualmethod.Theresults show that the proposed approach performs better on makespan, treatment chair occupancy,number of overtime hours and finding solutions at high demand levels.
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    A Community Disaster Resilience Index for Chile
    (2023) Bronfman, Nicolás; Castañeda González, Javiera Valentina; Guerrero Mancilla, Nikole Fernanda; Cisternas, Pamela; Repetto Lisboa, Paula Beatriz; Martínez, Carolina; Chamorro Giné, Marcela AlondraBronfman, Nicolás; Castañeda González, Javiera Valentina; Guerrero Mancilla, Nikole Fernanda; Cisternas, Pamela; Repetto Lisboa, Paula Beatriz; Martínez, Carolina; Chamorro Giné, Marcela Alondra
    Although Chile is one of the countries most exposed to natural hazards, to date there is no national index that shows the differences in resilience levels within the country. This study develops a community resilience index on a national scale based on the Baseline Resilience Community (BRIC) index. The BRIC index for Chile was built with 49 indicators, from different sources at the district level. Our results determined that resilience is not distributed homogeneously throughout the country. The highest levels of resilience are concentrated in the central macro-zone. In comparison, the extreme zones of Chile focus close to 90% of their population in the lowest levels, accounting for an uneven distribution of resources and services that impact resilience levels. These differences were mainly explained by indicators such as the percentage of the population without a health insurance system, the percentage of the population without internet access, and the percentage of electoral participation, among others. The results demonstrate that the BRIC model can be successfully implemented to assess community resilience in Chile and suggests the possibility of targeting resources and strategies to increase resilience in areas with the lowest levels of community resilience.
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    A comparative analysis of University Sustainable Travel Plans – Experience from Australia
    (2023) Nelson J. D.; Balbontin Tahnuz, Camila; Hensher D. A.; Beck M.
    Travel Demand Management (TDM) initiatives are widely applied by transport planners to establish and enable appropriate use of critical transport infrastructure. Less attention has been given to the specific case of TDM in an education precinct (university) context. Travel Plans have been promoted as a means for an organisation to encourage sustainable travel choices by their employees, visitors and customers. This paper offers an empirical contribution to the literature through a comparative qualitative evaluation of selected University Sustainable Travel Plans (USTPs) in Australia to identify the most important questions that a USTP should address explicitly. The evaluation comprised identification of a set of evaluation questions, completion of a template for each USTP considered and application of a simple scoring exercise. We also identify TDM measures that have been introduced as part of a USTP in response to the typical travel patterns exhibited in university settings. A contribution of this paper is to create a means of comparison of USTPs and to establish the components of a comprehensive travel plan.
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    A comparative analysis of virial black hole mass estimates of moderate-luminosity active galactic nuclei using Subaru/FMOS.
    (2013) Matsuoka, K.; Treister, Ezequiel; Silverman, J. D.; Schramm, M.; Steinhardt C. L.; Nagao, T.; Kartaltepe, J.; Sanders, David B.; Hasinger, G.; Akiyama, M.
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    A Comparison of Energy Efficiency Certification in Housing: A Study of the Chilean and Spanish Cases
    (2019) Sanhueza Durán, Francisco; Gómez Soberón, José M.; Valderrama Ulloa, Claudia; Ossio Castillo, Felipe Antonio
    Faced with implementing policies that seek to improve the energy efficiency of housing and reduce the impact of CO2 emissions, several countries are introducing (unilaterally or by international agreement) energy certification systems that allow the effects of these policies to be evaluated. This study aims to compare the energy efficiency certification systems in Spain and Chile, identifying convergent and divergent parameters, enabling the existing gaps to be identified and improvements noted for both systems. To do so, 20 sample dwellings in Santiago de Chile were evaluated, along with the local calculating tools in both countries. The analysis considered the aspects of regulation, its reach, the characterization of the models and the necessary indicators. The comparison identified, among others, differences such as obligatory implementation of the system, a study of the existing buildings in the focus area, the prevailing indicators for evaluating the effects of the buildings, the low incidence of mixed energy systems in the Chilean system and the possibility of proposing and evaluating improvements in the Spanish system. As a result, higher energy requirements and greater CO2 emissions were identified in the Chilean system, reaching differences of 42 kWh/m2/year in consumption and 14 kgCO2/ m2/year in emissions with regard to the Spanish qualification. The results of this comparison have facilitated the identification of improvements that will increase the evaluation standards of the Chilean system.
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    A competency-based model for construction supervisors in developing countries
    (2007) Ferrada Calvo, Ximena Verónica
    Purpose - To analyze the role of construction site supervisors, including foremen and general foremen, as front-line managers. The role is treated as a critical labor function and a source of value-added for construction management.||Design/methodology/approach - An original model based on the labor competency management framework is proposed for training, developing and certifying construction supervisors in Chile and other developing countries. This model was developed from the findings of a case study in which the competency framework was applied to a specific construction company.||Findings - This case study has demonstrated the significant potential of the competency framework for the Chilean construction sector, with its underdeveloped human resources management methods. In particular, this framework can be an effective approach to achieving the competencies required by construction site supervisors who must deal with inadequately trained workers, as is the case in many developing countries. The structured approach of the competency framework can help companies create more objective schemes for the design and implementation of training programs.||Practical implications - The application of the competency approach can greatly improve the human resources management function in construction companies as well as the site performance of their personnel. The findings obtained so far in Chile can also be projected to construction companies in other developing countries in the region.||Originality/value - This paper presents the first application of the competency framework to a Chilean construction company. This study is also original in the sense that the application described here was carried out in an environment where human resource conditions are quite deficient.
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    A Compound Real Option Approach for Determining the Optimal Investment Path for RPV-Storage Systems
    (The Energy Journal, 2022) Hassi, Benjamín A.; Reyes Torres, Tomas Hernan; Sauma Santis, Enzo Enrique
    The use of residential Photovoltaic-Storage systems may produce large benefits to owners and has expanded rapidly in recent years. Nonetheless, large uncertainties regarding the profitability of these systems make it necessary to incorporate flexibilities in their economic evaluations. This paper offers a new method to evaluate the compound flexibility of both the option of delaying investments and the option of further expanding the capacity of solar photovoltaic modules and batteries during the investment horizon. Flexibility is modeled as a compound real option, whose value is computed using a novel method that we call Compound Least Squares Monte Carlo (CLSM). The model is applied to the investment decisions associated to a residential Photovoltaic-Storage system. Results suggest that investors should use the proposed CLSM method in the economic valuation of multi-stage projects, since considering only a single flexibility could promote sub-optimal decisions. Moreover, in our case study, we show that it is optimal to break the investment down into two steps or more in 36% of future scenarios, on average.
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    A Comprehensive Review on Recycling of Construction Demolition Waste in Concrete
    (2023) HERBERT SINDUJA J; Thamilselvi Pachiappan; SIVA AVUDAIAPPAN; Nelson Maureira; Angel Roco-Videla; Guindos Bretones, Pablo; P. F. Parra
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    A comprehensive view of a strongly lensedplanck-associated submillimeter galaxy.
    (2012) Fu, Hai; Kim, Sam; Jullo, E.; Cooray, Asantha; Bussmann, R. S.; Ivison, R. J.; Pérez-Fournon, I.; Djorgovski, S. G.; Scoville, Nick Z.; Yan, L.; Riechers, D. A.
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    A computer environment for modeling and evaluating strategic decisions
    (1998) Alarcon Cardenas, Luis Fernando; Bastias, A; Wang, KCP