Temuco Catholic University
  • Temuco, Temuco, Chile
Recent publications
Zinc, iron, and silicon nanoparticles (NPs) are widely used in plant system. As their mineral base is a relevant constituent of the earth's crust, they are are commonly found in nature; indeed, Zn and Fe are considered essential nutrients. The Zn, Fe, and Si NPs effects on the plant are known, but its role in a nutrient acquisition under salinity and drought stress is less known. Thus, this chapter aimed to analyze critically the role of Zn, Fe, and Si NPs on crop plant nutrient acquisition under salinity and drought stress to comprehend their physiological and biochemical regulations. The specific information is scarce; however, we found tangential studies in several crop plants like cereals, legumes, oilseeds, and vegetables, where the NPs could play a relevant role in plant nutrition under abiotic stress allowing alleviate it and give a better plant response. Most of the authors suggest that smaller NPs increase the efficiency to counter the adverse effects. Moreover, direct exposition of NPs to soil or via fertilizer was preferable rather than foliar spraying methods. Zinc, iron, and silicon NPs affect the nutrient acquisition, trending to increase some macronutrient and micronutrients concentration in plant tissue; also, the relevant cations (K, Ca, and Mg) are increased, and Na is reduced, which is traduced in an increased of (K, Ca, and Mg)/Na ratio under salinity. The mechanisms underlying are not fully elucidated because several factors interact as NPs size and doses, and its electrical and chemical properties, mainly when are soil-applied. More studies are necessary to discover the primary mechanisms involved in the effect of NPs on nutrient stress, which could explain some observations and validate its use on the productive scale for contributing to satisfying the increasing food needs of the human population.
Background The associations of cancer with types of diets, including vegetarian, fish, and poultry-containing diets, remain unclear. The aim of this study was, therefore, to investigate the association of type of diet with all cancers and 19 site-specific incident cancers in a prospective cohort study and then in a meta-analysis of published prospective cohort studies. Methods A total of 409,110 participants from the UK Biobank study, recruited between 2006 and 2010, were included. The outcomes were incidence of all cancers combined and 19 cancer sites. Associations between the types of diets and cancer were investigated using Cox proportional hazards models. Previously published prospective cohort studies were identified from four databases, and a meta-analysis was conducted using random-effects models. Results The mean follow-up period was 10.6 years (IQR 10.0; 11.3). Compared with meat-eaters, vegetarians (hazard ratio (HR) 0.87 [95% CI: 0.79 to 0.96]) and pescatarians (HR 0.93 [95% CI: 0.87 to 1.00]) had lower overall cancer risk. Vegetarians also had a lower risk of colorectal and prostate cancers compared with meat-eaters. In the meta-analysis, vegetarians (Risk Ratio (RR): 0.90 [0.86 to 0.94]) and pescatarians (RR 0.91 [0.86; 0.96]) had lower risk of overall and colorectal cancer. No associations between the types of diets and prostate, breast, or lung cancers were found. Conclusions Compared with meat-eaters, vegetarians and pescatarians had a lower risk of overall, colorectal, and prostate cancer. When results were pooled in a meta-analysis, the associations with overall and colorectal cancer persisted, but the results relating to other specific cancer sites were inconclusive.
Background In 2013, PEDV was introduced in the United States (U.S.) and rapidly spread across the country. Here we describe the occurrence of PEDV in the growing pig herd of one large U.S. production system through an active surveillance set in place between October 2019 and November 2020 designed to assess disease status upon placement into the growing pig site, before shipping to the slaughter plant and when diarrhea events were present at the site. We also assessed the impact of preventive procedures implemented in PEDV incidence that comprised site-specific equipment segregation and biosecurity changes regarding personnel movement between sites. Results 36.50% (100/274) of the sites had at least one PEDV introduction event before preventive procedures were implemented, yielding an incidence rate of 2.41 per 100 farm-weeks. Most (63/100) of them occurred in sites where animals were placed negative and PEDV was detected in clinical samples in a median of 8 weeks post placement. After preventive procedures were implemented, the overall PEDV incidence rate dropped to 0.37 per 100 farm-weeks (84.65% reduction, p < 0.001). Conclusion These results highlight the importance of systematic surveillance to identify the burden of diseases, areas of improvement in prevention and control, and to allow the measurement of the impact of policy/protocol changes.
Photosynthetic traits, leaf soluble sugars and fruit yield and size were evaluated in order to identify the role of early sink manipulation (girdling and fruiting spur thinning applied in winter) in modulating the effect of late-deficit irrigation (recovering 60% of crop evapotranspiration during 36 days pre-harvest) in ‘Lapins’ sweet cherry branches. Photosynthesis (PN), stomatal conductance (gs), and fruit weight were affected by both treatments, whereas intercellular CO2 concentration of leaves (Ci), mesophyll conductance (gm), Rubisco carboxylase activity (Vcmax), electron transport rate (Jmax), leaf soluble sugars and branch yield were exclusively affected by sink manipulation. The effect of sink manipulation on PN was mainly observed in the girdling treatment as it was not altered by thinning. In girdled branches, PN dropped by 34%, accompanied by a two-fold increase in leaf soluble sugars, indicating that sink feedback regulation of carbon assimilation occurred. Irrespective of the irrigation, the higher PN observed in the controls were not sufficient to achieve the fruit weight and yield of the girdled branches, indicating that fruit carbon demand in control branches was source-limited. The depressed PN by girdling was associated with significant reductions in gs, gm, Vcmax and Jmax. Since lowered PN by deficit irrigation was neither attributable to a gs-associated decrease in Ci nor to changes in any other photosynthetic variable, further research is needed to clarify this point. Results showed that irrigation deficit was sufficient to reduce PN in girdled branches, whereas it had no effect in control and thinned branches. Thus, the depressive effect of deficit irrigation on PN appeared to be exacerbated by the sink effect.
Phosphorus (P) cycling by microbial activity is highly relevant in the eutrophication of lakes. In this context, the contents of organic (Po) and inorganic (Pi) phosphorus, the activity of acid (ACP) and alkaline (ALP) phosphomonoesterase (Pase), and the abundances of bacterial Pase genes (phoD, phoC, and phoX) were studied in sediments from Budi Lake, a eutrophic coastal brackish water lake in Chile. Our results showed spatiotemporal variations in P fractions, Pase activities, and Pase gene abundances. In general, our results showed higher contents of Pi (110–144 mg kg⁻¹), Po (512–576 mg kg⁻¹), and total P (647–721 mg kg⁻¹) in sediments from the more anthropogenized sampling sites in summer compared with those values of Pi (86–127 mg kg⁻¹), Po (363–491 mg kg⁻¹) and total P (449–618 mg kg⁻¹) in less anthropogenized sampling sites in winter. In concordance, sediments showed higher Pase activities (μg nitrophenyl phosphate g⁻¹ h⁻¹) in sediments from the more anthropogenized sampling sites (9.7–22.7 for ACP and 5.9 to 9.6 for ALP) compared with those observed in less anthropogenized sampling sites in winter (4.2–12.9 for ACP and 0.3 to 6.7 for ALP). Higher abundances (gene copy g⁻¹ sediment) of phoC (8.5–19 × 10⁸), phoD (9.2–47 × 10⁶), and phoX (8.5–26 × 10⁶) genes were also found in sediments from the more anthropogenized sampling sites in summer compared with those values of phoC (0.1–1.1 × 10⁸), phoD (1.4–2.4 × 10⁶) and phoX (0.7–1.2 × 10⁶) genes in the less anthropogenized sites in winter. Our results also showed a positive correlation between P contents, Pase activities, and abundances of bacterial Pase genes, independent of seasonality. The present study provided information on the microbial activity involved in P cycling in sediments of Budi Lake, which may be used in further research as indicators for the monitoring of eutrophication of lakes.
Deep learning has provided promising results in various applications; however, algorithms tend to be overconfident in their predictions, even though they may be entirely wrong. Particularly for critical applications, the model should provide answers only when it is very sure of them. This article presents a Bayesian version of two different state-of-the-art semantic segmentation methods to perform multi-class segmentation of foods and estimate the uncertainty about the given predictions. The proposed methods were evaluated on three public pixel-annotated food datasets. As a result, we can conclude that Bayesian methods improve the performance achieved by the baseline architectures and, in addition, provide information to improve decision-making. Furthermore, based on the extracted uncertainty map, we proposed three measures to rank the images according to the degree of noisy annotations they contained. Note that the top 135 images ranked by one of these measures include more than half of the worst-labeled food images.
The thesis proposed in this chapter refers to the impossibility of forming a regional communication research agenda without a critical, decolonising review of the epistemological coordinates governing the work of the social sciences in general and of communication. However, the first step towards this is to break through the analysis of the academic field itself in order to situate the problem beyond scientific rationality. The central argument of this thesis runs as follows: for the shape of a decolonised regional research agenda, one must look into the kind of rationality underlying the shape of the historical development of Western modernity, which, we claim, has managed to impose itself as a universal framework based on dispositifs of representation, exclusion and delegitimisation of any possible alterity.
Resumen La comunicación oral como eje en el plan de estudio escolar en Chile es un tema relevante para las comunidades indígenas mapuche de la Región de La Araucanía, sobre todo, porque la oralidad es la fuente de conocimiento y transmisión de saberes para este pueblo. Aunque este eje se considera en el currículo oficial, se enseña y se evalúa desde métodos educativos occidentales. Este estudio tiene como finalidad identificar y describir componentes de la comunicación oral, cuya inclusión es necesaria en escuelas con estudiantes mapuche y chileno-occidentales. Para esto, el estudio fue participativo en base al enfoque dialógico-kishu kimkelay ta che, por medio de una fase de revisión de fuentes documentales, y una fase de trabajo con profesores/as que se desempeñan en contexto indígena rural y urbano. Entre los principales resultados, se identifica la distancia epistémica entre la oralidad de los programas ministeriales y la experiencia del profesorado, como también, se presentan recursos metodológicos, tanto didácticos como evaluativos, cuya incorporación es importante en las prácticas de aula cuando se desempeña en contextos con población indígena.
El artículo propone una teoría sustantiva que busca explicar el fenómeno de la invisibilidad social del pueblo mapuche en el currículo escolar de Historia y Ciencias Sociales a partir de lo que piensan, dicen y hacen los profesores y profesoras de educación primaria en Chile. La investigación se llevó a cabo través de la teoría fundamentada en su modalidad sistemática y reflexiva. El estudio se desarrolló a partir de la triangulación de cuestionarios, entrevistas y observaciones participantes aplicadas a docentes del ciclo básico. El proceso de investigación integró los diversos componentes de la teoría fundamentada en un esquema organizativo que incluyó la estructura propuesta por Strauss y Corbin (2002) con el objetivo de formar nuestra teoría. La codificación de los datos fue realizado con el apoyo del software ATLAS.ti. Los resultados revelan una política oficial del conocimiento que opera en el currículo y que transforma en invisible la historia y la memoria mapuche en el currículo de Historia. Además, intervienen ciertos mecanismos que mantienen la invisibilidad social como las pruebas estandarizadas, la formación de docentes y la comunidad educativa. Palabras clave Enseñanza de la historia-Cultura mapuche-Diversidad cultural-Diseño curricular. 1-El conjunto de datos que da soporte a los resultados de este estudio no está disponible públicamente, debido a los protocolos de confidencialidad de los datos. La solicitud de acceso a los datos se puede hacer directamente al autor, por el ARTÍCULOS This content is licensed under a Creative Commons attribution-type BY-NC.
The deep-water rose shrimp, Parapenaeus longirostris (H. Lucas, 1846), is the most dominant shrimp species on the Algerian west coast. In that area, the diet of P. longirostris was studied between July 2020 and June 2021. This approach to the diet of the rose shrimp was based on analysis of the stomach contents and determination of the ingested prey. A seasonal sampling was carried out in the main fishing ports (Béni Saf, Bouzedjar, Oran and Mostaganem). The results obtained showed that the shrimp feed intensively in spring and increasingly less in winter and summer. Crustaceans, foraminiferans, polychaetes, and molluscs constituted the most frequent preys in the diet, with respective frequencies of 58.85, 55.95, 36.63 and 32.04%. Small microplancton and mesoplancton prey (radiolarians, copepods, and various larvae) were less important in the diet of P. longirostris . Fish and echinoderms constitute accidental prey, of which the frequency is less than 10%.
This article proposes a substantive theory intended to explain the Mapuche people’s social invisibility phenomenon in the History and Social Sciences school curriculum, based on what elementary school teachers think, say and do in Chile. The research method was designed using Grounded Theory through its systematic and reflexive modality.This study was developed by means of a triangulation method combining questionnaires, interviews and participant observations, applied to elementary school teachers. The investigation integrated the different elements of Grounded theory into an organizational scheme that included the structure proposed by Strauss and Corbin (2002) and the research process for the purpose of developing our theory. The data codification process was conducted with the help of ATLAS.ti software. The results show an oficial knowledge policy that operates within the curriculum and makes the Mapuche history and memory invisible in the History school curriculum. Furthermore, there are certain mechanisms that intervene in the maintenance of this social invisibility, such as standardized tests, the professional development of elementary school teachers and the educational community.
The aim was to analyze the reliability and validity of a low-cost instrument, based on a radar system, to quantify the kicking ball speed in soccer. A group of 153 male soccer players (under-13, n = 53; under-15, n = 54; under-18, n = 46) participated in this study. Each player performed three kicks on the goal in a standardized condition while the ball speed was measured with three different devices: one Radar Stalker ATS II® (reference criterion) and two Supido Radar® (Supido-front of the goal and Supido-back of the goal). The standard error of measurement (SEM) expressed as a coefficient of variation (CV) and the intraclass correlation coefficient (ICC) were employed for assessing the reliability of each instrument. Stalker and Supido-back showed very high absolute (CV = 4.0–5.4%) and relative (ICC = 0.945–0.958) reliability, whereas Supido-front resulted in moderate to low reliability scores (CV = 7.4–15%, ICC = 0.134–0.693). In addition, Lin’s concordance correlation coefficient (CCC) values revealed an ‘almost perfect’ agreement between Stalker and Supido-back for the average (r = 0.99) and maximal (r = 0.98) ball speed, regardless of the ball speed range analyzed. However, Supido-front resulted in a poor degree of concordance (CCC = 0.688) and a high magnitude of error (17.0–37.5 km·h−1) with the reference Stalker radar gun. The Supido Radar® placed behind the goal could be considered a reliable and valid device for measuring ball speed in soccer.
A new Rhodamine-based ́́Turn On‘‘ fluorescent probe (E)-3',6'-bis(diethylamino)-2-((2,5-dimethoxybenzylidene)amino)spiro[isoindoline-1,9'-xanthen]-3-one (WGB) was synthesized. Results show that WGB is selective for Cu2+ cations, forming a WGB-Cu2+ complex in a 2:1 stoichiometry, confirmed through density functional theory (DFT) electronic structure calculations and reactive molecular dynamics (MD) simulations. Theoretical calculations agreed with the experimental data. The detection limit of WGB-Cu+2 complex is 6.76 x 10-8 M. Preliminary studies employing epifluorescence microscopy demonstrate that Cu2+ can be imaged in neuroblastoma SH-SY5Y cells treated with WGB.
This article analyses how the first circumnavigation of the world, from 1519 to 1522, introduced South America as a key space in the formation of the ‘global’, thus producing a historical point of inflection. We examine the commercial and political plans and networks that began to function as a result of this new connectivity, which turned the American continent into a major global axis. The analysis focuses on the way in which this voyage gave new prominence to an unexplored region of the world, namely the southernmost tip of America, thus changing the notion of habitability that had prevailed for centuries in Europe. These changes questioned the authority of ‘ancient’ Greek thinkers and strengthened a European historical narrative that appropriated the discovered territories and distinguished the extreme southern part of America from other southern regions, as symbolized through figures such as the Patagonian giants. I consider these changes based on evidence from Spanish sources.
Aliarcobacter butzleri (formerly known as Arcobacter butzleri) is an emerging food-borne zoonotic pathogen that establishes in vitro endosymbiotic relationships with Acanthamoeba castellanii, a free-living amoeba. Previously, we described that this bacterium acts as an endocytobiont of A. castellanii, surviving for at least 10 days in absence of bacterial replication. Thus, the aim of this study was to evaluate the ability of A. butzleri to survive as a long-term endosymbiont of A. castellanii for 30 days in two models of symbiotic interaction with A. castellanii: (i) endosymbiotic culture followed by gentamicin protection assay and (ii) transwell co-culture assay. The results allow us to conclude that A. butzleri is capable of surviving as an endosymbiont of A. castellanii for at least 30 days, without multiplying, under controlled laboratory conditions. In addition, in the absence of nutrients and as both microorganisms remain in the same culture, separated by semi-permeable membranes, A. castellanii does not promote the survival of A. butzleri, nor does it multiply. Our findings suggest that the greater survival capacity of A. butzleri is associated with their endosymbiont status inside A. castellanii, pointing out the complexity of this type of symbiotic relationship.
Aims: People with diabetes are at high risk for cardiovascular events including heart failure. We examined the effect of the glucagon-like peptide 1 agonist dulaglutide on incident heart failure events and other cardiovascular outcomes in those with or without prior heart failure the randomized placebo-controlled Researching Cardiovascular Events with a Weekly Incretin in Diabetes (REWIND) trial (ClinicalTrials.gov number NCT01394952). Methods and results: The REWIND major adverse cardiovascular event (MACE) outcome was the first occurrence of a composite endpoint of non-fatal myocardial infarction, non-fatal stroke, or death from cardiovascular causes (including unknown causes). In this post-hoc analysis, a heart failure event was defined as an adjudication-confirmed hospitalization or urgent evaluation for heart failure. Of the 9901 participants studied over a median follow-up of 5.4 years, 213/4949 (4.3%) randomly assigned to dulaglutide and 226/4952 (4.6%) participants assigned to placebo experienced a heart failure event (HR 0.93, 95% CI 0.77- 1.12; P=0.46). In the 853 (8.6%) participants with heart failure at baseline, there was no change in either MACE or heart failure events with dulaglutide as compared to participants without heart failure (p=0.44 and 0.19 for interaction, respectively). Combined CV death and heart failure events were marginally reduced with dulaglutide compared to placebo (HR 0.88, 95% CI: 0.78-1.00; p=0.050) but unchanged in patients with and without heart failure at baseline (p=0.31). Conclusions: Dulaglutide was not associated with a reduction in HF events in patients with type 2 diabetes regardless of baseline HF status over 5.4 years of follow up. This article is protected by copyright. All rights reserved.
Environmental management has increasingly focused on promoting social engagement in biodiversity and ecosystem services conservation as a way to foster sustainability. However, a critical challenge that still remains is the adequate implementation of strategies of communication, education, and participation (CEPA) oriented to reconnect the social and ecological dimensions in the systems. This study analyzed the main features and types of CEPA implemented by the Colombian Regional Autonomous Corporations in environmental management projects that consider ecosystem services. We found a variety of CEPA focused on a wide range of stakeholders. Communication and education were the most frequently implemented in the projects. Within communication, spreading information about the projects was the most common, while education focused on instrumental training of local communities. Participation, the less frequently implemented, mainly aimed to ensure government and decision-makers involved in the initial phases of the projects. We conclude that there is a need to increase and improve education strategies in conservation projects to make decisions based on critical and reflective thinking, and foster the engagement of a broader set of stakeholders in the processes.
Influenza is an important respiratory disease of pigs and humans. Controlling influenza in pigs is challenging due to the substantial genetic diversity of influenza A virus (IAV). In this study, we assessed the impact of internal biosecurity practices directed at limiting exposure of piglets to IAV before weaning; evaluated the association of sow parity with IAV prevalence in piglets and the levels of maternally derived antibodies (MDA), and documented the frequency of detection of IAV on farmworkers’ hands and the instruments used when handling pigs. The control group included litters in rooms where no specific changes were made to standard farm procedures. The treatment group included litters in rooms where no cross-fostering or nurse sows use was allowed, and where farmworkers were required to change gloves between litters when handling pigs. Both, younger (≤ Parity 3) and older parity sows (>Parity 3) were represented in all rooms included in the study. Overall, litters in the treatment group had lower IAV prevalence (29.9%) than litters in the control group (44.2%) (p < 0.001), and at day 8 of age the litters from the control group had 7.5 times higher IAV prevalence than the litters from the treatment group. However, at weaning differences were not found (77.2% vs. 81% for treatment vs. control, respectively, p = 0.41). There were no differences in IAV detection between parity groups at any of the sampling points (p = 0.86) and incidence of detection in sows from farrowing to weaning was 29%. Piglets that tested ELISA negative were 1.3 times more likely to test IAV positive than piglets that were ELISA positive for IAV antibody test, suggesting that effective colostrum intake may reduce the likelihood of infection. IAV was detected on 46% of the instruments used when handling piglets and on 58% of farmworkers’ hands, indicating the potential risk for mechanical transmission of IAV in pigs. Overall, we showed that the implementation of internal biosecurity practices that limit IAV exposure to newborn piglets helped delay IAV infections but were not sufficient to reduce the prevalence of IAV infection in litters at weaning.
Cyclotides are mini-proteins with potent bioactivities and outstanding potential for agricultural and pharmaceutical applications. More than 450 different plant cyclotides have been isolated from six angiosperm families. In Brazil, studies involving this class of natural products are still scarce, despite its rich floral biodiversity. Herein were investigated the cyclotides from Anchietea pyrifolia roots, a South American medicinal plant from the family Violaceae. Fourteen putative cyclotides were annotated by LC-MS. Among these, three new bracelet cyclotides, anpy A−C, and the known cycloviolacins O4 (cyO4) and O17 (cyO17) were sequenced through a combination of chemical and enzymatic reactions followed by MALDI-MS/MS analysis. Their cytotoxic activity was evaluated by a cytotoxicity assay against three human cancer cell lines (colorectal carcinoma cells: HCT-116 and HCT 116 TP53 −/− and breast adenocarcinoma, MCF-7). For all assays, the IC 50 values of isolated compounds ranged between 0.8 and 7.3 μM. CyO17 was the most potent cyclotide for the colorectal cancer cell lines (IC 50 , 0.8 and 1.2 μM). Furthermore, the hemolytic activity of anpy A and B, cyO4, and cyO17 was assessed, and the cycloviolacins were the least hemolytic (HD 50 > 156 μM). This work sheds light on the cytotoxic effects of the anpy cyclotides against cancer cells. Moreover, this study expands the number of cyclotides obtained to date from Brazilian plant biodiversity and adds one more genus containing these molecules to the list of the Violaceae family.
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2,191 members
Gustavo Curaqueo
  • Facultad de Recursos Naturales / Departamento de Ciencias Agropecuarias y Acuícolas
Rodrigo Tomás Del Valle
  • Facultad de Educación
Cesar Cuevas
  • Ciencias Biológicas y Químicas
Angélica Casanova-Katny
  • Escuela de Ciencias Ambientales
Alexander Ortloff
  • Escuela de Medicina Veterinaria
Information
Address
Manuel Montt Nro. 56, Temuco, Casilla 15-D, Temuco, Temuco, Chile
Head of institution
Aliro Borquez
Website
https://uct.cl/
Phone
+56 (45) 2205205