Artículos de Investigación

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Underutilized Native Biobío Berries: Opportunities for Foods and Trade
(2018)
Diana María López-celis
;
Nieves Baenas Navarro
;
Jorge Andrès Retamal-salgado
;
Nelson Stiven Zapata Rios
;
Diego Ángel Moreno-fernández
The Biobío Region in Chile presents special edaphoclimatic characteristics and biodiversity that make it suitable for the introduction and development of some berries that are understudied in terms of their health-promoting composition and characteristics. Chilean strawberry (Fragaria chiloensis ssp. chiloensis, form chiloensis) and calafate (Berberis microphylla G. Forst.) have been underused despite having interesting nutritive values and health-promoting capacities. The polyphenolic compositions of Chilean strawberry and calafate were characterized by HPLC-DAD-ESI-MSn analyses, as well as their antioxidant potential (in ORAC and DPPH assays). The major secondary metabolites present in Chilean strawberry and calafate were ellagic acid derivatives and anthocyanins, respectively, being the anthocyanins more closely related to the higher antioxidant capacity found in the berries. Therefore, the Biobío Region berries analyzed are rich in bioactive phytochemicals with health-promoting characteristics. This represents an opportunity for the food industry and for international trade with Chilean berries, as well as a potential way of promoting rural development in the region.
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Residual effect of cadmium applications in different crop rotations and environments on durum wheat cadmium accumulation
(2019-01)
J. Hirzel
;
J. Retamal-Salgado
;
I. Walter
;
I. Matus
Cadmium (Cd) is one of the heavy metals commonly present in soils that is toxic for living organisms and carcinogenic in humans. The uptake of Cd by a crop depends on various factors such as soil properties, plant-soil interaction, fertilizer management, and pre vious crop. The aim of the present study was to evaluate the residual effect of three Cd rates applied in three preceding crops (durum wheat [Triticum turgidum L. var durum], white lupine [Lupinus albus L.], and narrow-leafed lupine [Lupineus angustifolius L.]) on total dry matter, grain yield, and Cd concentration and uptake in three durum wheat cultivars in four envi ronments. The residual effect of a cadmium chloride (CdCl2 ) dose applied in the preceding crop to durum wheat was affected by location and previous crop, with the greatest effect in La Serena with narrow-leafed lupines as the preceding crop. Finally, in soils where a critical level of Cd is present, narrow-leafed lupines should not be used as a previous crop to durum wheat.
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Description of intraoral pressures on sub-palatal space in young adult patients with normal occlusion
(2015)
Fuentes, Ramón
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Engelke, Wilfried
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Flores, Tania
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Navarro, Pablo
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Borie, Eduardo
Under normal conditions, the oral cavity presents a perfect system of equilibrium between teeth, soft tissues and tongue. The equilibrium of soft tissues forms a closed capsular matrix, generating differences with the atmospheric environment. This difference is known as intraoral pressure. Negative intraoral pressure is fundamental to the stabilization of the soft palate and tongue, reducing neuromuscular activity for the permeability of the respiratory tract. Thus, the aim of this study was to describe the variations of intraoral pressure of the sub-palatal space (SPS) under different physiological conditions and biofunctional phases. A case series was conducted with 20 individuals aged between 18 and 25. The intraoral pressures were measured through a system of cannulae connected to a digital pressure meter in the SPS during seven biofunctional phases. Descriptive statistics were used based on the mean and standard deviation. The data recorded pressure variations under physiological conditions, reaching 65 mbar as the intraoral peak in forced inspiration. In the swallowing phase, peaks reached -91.9 mbar. No pressure variations were recorded in terms of atmospheric changes with the mouth open and semi-open. The data obtained during the swallowing and forced inspiration phases indicated forced lingual activity. In the swallowing phase, the adequate position of the tongue creates negative intraoral pressure, which represents a fundamental mechanism for the physical stabilization of the soft palate. This information could contribute to subsequent research into the treatment of primary roncopathies.
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Supernaturally Infused or Naturally Emerged Soul? A Study of the Appeal of Theistic Evolutionist Systems to Dual Anthropology
(2014)
Răzmeriță, Gheorghe
The article studies the relationship between theistic evolutionism and the dualistic and sinful aspects of the human nature. This engagement proves essential to Adventist theology, with its particular creationism and anthropology. Two questions stand out in this study. First, how do the concepts of dualism and sin affect theistic evolutionism? Could some Adventist theologians who may be tempted to accept theistic evolutionism remain consistent with their biblical anthropology and still embrace theistic evolutionism? Besides the introduction and conclusion, the article is structured in three major sections: theistic evolutionist systems that integrate dualism, theistic evolutionist systems that do not integrate dualism, and an assessment of both options.
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Maximum electron concentration and total electron content of the ionosphere over Concepción, Chile, prior to the 27 February 2010 earthquake
(2013)
Ovalle, E.M.
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Bravo M.A.
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Villalobos Núñez, Carlos Ulises
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Foppiano A.J.
Ionospheric variability observed prior to mayor earthquakes has been studied for decades. In particular, in many such studies the identification of ionospheric precursors of large earthquakes has been regarded as a specific goal. This paper analyses the observations of the maximum electron concentration (NmF2) over Concepción (36.8°S; 73.0°W) and of the total electron content (TEC) for an area covering the rupture zone corresponding to the very large Chile earthquake of 27 February 2010. The analyses used here are similar to those published before for many earthquakes in Taiwan, Japan and Russia. Possible NmF2 and TEC precursors are compared with other precursors proposed for the same earthquake using different TEC determinations and satellite observations of electron/ion concentration, energetic particle bursts and electromagnetic emissions. Some possible precursors derived from the various observations are consistent with each other. However, none can be unambiguously associated to the Chilean earthquake.
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Cold tolerance evaluation in Chilean rice genotypes at the germination stage
(2013)
Gabriel Donoso Ñanculao
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Mario Paredes Cárcamo
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Oscar Arbiza de los Santos
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Viviana Becerra Velásquez
Low temperature is the most important abiotic stress affecting rice (Oryza sativa L.) yield in Chile. Rice in Chile is usually planted when the minimum air temperatures are below 12 °C. This temperature is lower than the optimum needed for normal rice germination. Therefore, the aim of this study was to evaluate cold tolerance in 20 experimental lines from the Rice Breeding Program of the Instituto de Investigaciones Agropecuarias (INIA), Chile, at the germination stage. Coleoptile length reduction (CRED), coleoptile length after cold treatment (CLEN), coleoptile length recovery (CREC), and coleoptile regrowth (CREG) were evaluated at 13 °C for 4 d using ‘Diamante-INIA’ as the cold-tolerant control. To find genotypes with cold tolerance (low CRED value and high CLEN, CREC, and CREG values), genotypes were ranked, a biplot of principal components, and cluster analysis were performed. No differences were found among genotypes in the ranking based on CREC value so this trait was not considered. Analysis showed that only three experimental lines had cold tolerance similar to that of ‘Diamante-INIA’; all other experimental lines exhibited intermediate to low cold tolerance. These results showed low cold tolerance of some Chilean genotypes at the germination stage, thus confirming the need to evaluate the rest of the germplasm from the Rice Breeding Program.
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A <i>SHMT1</i> variant decreases the risk of nonsyndromic cleft lip with or without cleft palate in Chile
(2019)
Carlos Salamanca
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Patricio González‐Hormazábal
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Andrea S. Recabarren
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Pamela A. Recabarren
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Roberto Pantoja
<jats:title>Abstract</jats:title><jats:sec><jats:title>Objective</jats:title><jats:p>To assess the association between polymorphic variants from <jats:italic>SHMT1</jats:italic> and <jats:italic>MTHFS</jats:italic> genes, involved in the cytoplasmic futile folate cycle, and the risk of nonsyndromic cleft lip with or without cleft palate (NSCL/P) in the Chilean population.</jats:p></jats:sec><jats:sec><jats:title>Subjects and Methods</jats:title><jats:p>In a sample of 139 Chilean NSCL/P cases and 278 controls, we obtained the genotypes for nine variants of <jats:italic>SHMT1</jats:italic> and <jats:italic>MTHFS</jats:italic> and the association between them and the phenotype was evaluated using odds ratios (OR) in additive (allele), dominant, and recessive models.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>After correction for multiple comparisons, only the variant rs1979277 (G > A; p.Leu474Phe) from <jats:italic>SHMT1</jats:italic> showed a significant and protective effect for additive (OR 0.60; 95% CI 0.42–0.86; <jats:italic>p</jats:italic> = .0054, <jats:italic>q</jats:italic> = 0.0488) and dominant models (OR 0.48; 95% CI 0.29–0.75; <jats:italic>p</jats:italic> = .0009; <jats:italic>q</jats:italic> = 0.0081). Our bioinformatic prediction plus functional evidence from previous reports demonstrate that the A allele for this missense variant decreases the enzymatic activity.</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>Owing to the rs1979277 A allele, which reduces the cytoplasmic SHMT activity and has a higher frequency in controls than in NSCL/P cases, we hypothesized that a low enzyme activity may increase the cytoplasmic concentration of folates and, therefore, explain the protective role against OFCs.</jats:p></jats:sec>
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Level of physical activity, eating habits, and their relationship with academic performance in adolescent students at COMEDUC foundation, Chile.
(2019)
Ibarra Mora, Jessica
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Ventura-Vall-Llovera, Carles
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Hernández-Mosqueira, Claudio
This study was aimed to determine the impact of the level of physical activity and eating habits in the academic performance of an adolescent school population in Chile. The study has a descriptive cross-cutting design. The sample was formed by 2116 students (60.8% women and 39.2% men), later it was stratified according to level of physical activity and eating habit. Habits were determined by means of a 24-hour reminder, the level of physical activity by means of the International Physical Activity Questionnaire, and the general school averages, mathematics and language, as well as standardized tests were considered. For the analysis of data, descriptive and inferential statistics were used. The results indicated that having a high level of physical activity and having the main meals per day is associated with a better school performance, highlighting the importance of promoting these habits among the school community.
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The Effectiveness of the Instruction of the Intonation of English Implications to L1 Spanish Trainee Teachers
(2019)
Marco Sandro Antonio Ugarte Olea
When it comes to Second and Foreign Language Teaching, the teaching of pronunciation has, for long, been neglected (Derwin & Munro, 2005) and it has not been given due attention in textbooks (Thompson, 1995). Additionally, studies tend to focus on only some intonation patterns such as wh- questions and yes-no questions, leaving other patterns which are as important unexplored. Thus, a research gap is generated. This study aims to narrow that gap by means of exploring the effectiveness of the teaching of intonation to Spanish-speaking trainee teachers at a Chilean university. The study focuses on a less familiar intonation pattern, that of utterances which express implied information, namely, implications. The study involved 9 participants (3 males, and 6 females) who were in the process of becoming English teachers and who were enrolled in an English phonetics course. All participants took a pre-test followed by a four-session intervention on the intonation of English implications and a post-test which involved the reading of 29 prompts. In order to compare pre- and post-test results, a Wilcoxon signed-ranked test was run. The results drawn from the non-parametric test revealed that the participants were able to perform English intonation for implications better after having received training (Mdn=22) than before the treatment (Mdn=11), Z=-2,668, p=0,008.
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Lingua Franca Core: A Plausible Option?
(2019)
Marco Sandro Antonio Ugarte Olea
<jats:p>One important decision that English language teachers should make is to decide on a pronunciation model. This decision should be based not only on mere preference, but also on technical information. This paper seeks to review the Lingua Franca Core (LFC), a pronunciation model proposed by Jennifer Jenkins (1998, 2000) in an attempt to facilitate communication for L2 speakers. This paper also presents a set of reactions that her proposal has prompted in scholars in the area of teaching English language pronunciation. Such reactions are the manifestation of rejection of the LFC which is based on a number of arguments. First, there is no agreement as to the number of interactions that occur in English in L1 and L2 contexts. Thus, the predominant use of L2 speakers of English is questioned. Secondly, the advantage of the intelligibility of non-native speakers over native speakers in interaction with other non-native speakers is also subjected to scrutiny. Finally, a special focus on implications for the L1-Spanish-speaking learner of English is proposed, as well as for English language teachers who teach pronunciation. For instance, a series of issues which could facilitate the learner’s workload is discussed. One the other hand, the implementation of the LFC implies that the amount of work to be done by the teacher would be drastically increased. This necessarily entails a disadvantage in terms of both time and teaching materials to be allocated by the English Language Teaching (ELT) professional.</jats:p>

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