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The use of trace elements in agriculture as a complement to crop fertilization programs is a practice that is gaining importance and relevance worldwide. Iodine and selenium perform essential functions in human health, related to the proper functioning of the thyroid gland, acting as antioxidants and antiproliferatives, and their limited intake through food consumption can cause malnutrition, reflected in the abnormal development and growth of humans. This research aimed to evaluate the nutraceutical quality of tomato (Solanum lycopersicum L.) in response to seed priming based on KIO3 (0, 100, 150, 200, 250 mg L-1) and Na2SeO3 (0, 0.5, 1, 2, 3 mg L-1), performed by interaction from a 52-factorial design and by independent factors in a 24-h imbibition time. The tomato crop was established under greenhouse conditions in 10-L polyethylene containers containing peat moss and perlite 1:1 (v/v). Regarding non-enzymatic antioxidant compounds, lycopene, ß-carotene and flavonoid contents in tomato fruits significantly increased with KIO3 and Na2SeO3 treatments; however, vitamin C content was negatively affected. KIO3 increased the phenol and chlorophyll-a contents of leaves. In relation to enzymatic activity, KIO3 positively influenced GSH content and PAL activity in tomato fruits. KIO3 also positively influenced GSH content in leaves while negatively affecting PAL and APX activities. Na2SeO3 favored GSH content and GPX activity in tomato fruits and leaves. Na2SeO3 negatively affected the antioxidant capacity of hydrophilic compounds by ABTS in fruits and leaves and favored hydrophilic compounds by DPPH in leaves. Seed imbibition based on KIO3 and Na2SeO3 is a method that is implemented in the tomato crop and presents interesting aspects that favor the nutraceutical quality of tomato fruits, which may contribute to increasing the intake of these minerals in humans through tomato consumption.

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Zn is an indispensable nutrient for crops that usually presents low bioavailability. Different techniques have been proposed to improve the bioavailability of Zn, including the use of nanofertilizers. The objective of the study was to evaluate the applications of drench (D) and foliar (F) ZnO nanoparticles (NZnO) compared to those of ionic Zn2+ (ZnSO4) in lettuce. The plants cv. Great Lakes 407 was produced in pots of 4 L with perlite-peat moss (1:1) under greenhouse conditions. The treatments consisted of NZnO applications that replaced the total Zn provided with a Steiner solution, as follows: Zn2+ (100%D) (control); Zn2+ (50%D+50%F); NZnO (100%D); NZnO (50%D+50%F); NZnO (75%D); NZnO (50%D); NZnO (75%F) and NZnO (50%F). Four applications of Zn were made with a frequency of 15 days. 75 days after transplant (DAP), the fresh and dry biomass, chlorophyll a, b, and ß-carotene, phenolics, flavonoids, antioxidant capacity, vitamin C, glutathione, H2O2, total protein, and enzymatic activity of PAL, CAT, APX, and GPX were evaluated. The mineral concentrations (N, P, K, Ca, Mg, S, Cu, Fe, Mn, Mo, Zn, Ni, and Si) in the leaves and roots of plants were also determined. The results showed that, compared to Zn2+, NZnO promoted increases in biomass (14-52%), chlorophylls (32-69%), and antioxidant compounds such as phenolics, flavonoids, and vitamin C. The activity of enzymes like CAT and APX, as well as the foliar concentration of Ca, Mg, S, Fe, Mn, Zn, and Si increased with NZnO. A better response was found in the plants for most variables with foliar applications of NZnO equivalent to 50-75% of the total Zn2+ applied conventionally. These results demonstrate that total replacement of Zn2+ with NZnO is possible, promoting fertilizer efficiency and the nutraceutical quality of lettuce.

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The objective of this review is to present a compilation of the application of various biostimulants in strawberry plants. Strawberry cultivation is of great importance worldwide, and, there is currently no review on this topic in the literature. Plant biostimulation consists of using or applying physical, chemical, or biological stimuli that trigger a response-called induction or elicitation-with a positive effect on crop growth, development, and quality. Biostimulation provides tolerance to biotic and abiotic stress, and more absorption and accumulation of nutrients, favoring the metabolism of the plants. The strawberry is a highly appreciated fruit for its high organoleptic and nutraceutical qualities since it is rich in phenolic compounds, vitamins, and minerals, in addition to being a product with high commercial value. This review aims to present an overview of the information on using different biostimulation techniques in strawberries. The information obtained from publications from 2000-2022 is organized according to the biostimulant's physical, chemical, or biological nature. The biochemical or physiological impact on plant productivity, yield, fruit quality, and postharvest life is described for each class of biostimulant. Information gaps are also pointed out, highlighting the topics in which more significant research effort is necessary.

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Currently, the use of biostimulants in agriculture is a tool for mitigating certain environmental stresses. Brown algae extracts have become one of the most important categories of biostimulants in agriculture, and are derived from the different uses and positive results obtained under optimal and stressful conditions. This study aimed to examine the efficacy of a foliar application of a hydroalcoholic extract of Sargassum spp. and two controls (a commercial product based on Ascophyllum nodosum and distilled water) with regard to growth, the antioxidant system, and the expression of defense genes in tomato seedlings grown in nonsaline (0 mM NaCl) and saline (100 mM NaCl) conditions. In general, the results show that the Sargassum extract increased the growth of the seedlings at the end of the experiment (7.80%) compared to the control; however, under saline conditions, it did not modify the growth. The Sargassum extract increased the diameter of the stem at the end of the experiment in unstressed conditions by 14.85% compared to its control and in stressful conditions by 16.04% compared to its control. Regarding the accumulation of total fresh biomass under unstressed conditions, the Sargassum extract increased it by 19.25% compared to its control, and the accumulation of total dry biomass increased it by 18.11% compared to its control. Under saline conditions, the total of fresh and dry biomass did not change. Enzymatic and nonenzymatic antioxidants increased with NaCl stress and the application of algal products (Sargassum and A. nodosum), which was positively related to the expression of the defense genes evaluated. Our results indicate that the use of the hydroalcoholic extract of Sargassum spp. modulated different physiological, metabolic, and molecular processes in tomato seedlings, with possible synergistic effects that increased tolerance to salinity.

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Global changes require urgent integration of health and wellbeing into all urban policies. Complex social and environmental factors define wellbeing outcomes and inequities present in cities. Additionally, political decisions are seldom thought and developed considering the needs and participation of children and adolescents. The REDibuja study aims to develop a multidimensional framework of wellbeing for children and adolescents and to validate an index of opportunities for better wellbeing for children and adolescents in the urban context of Temuco, Chile. This child-centered and cross-sectional study will involve mixed methodologies throughout the implementation of five work packages for two years (2022-2023): (1) development of a conceptual framework for child and adolescent wellbeing, (2) integration of available and public data, (3) studies in the local context, (4) data integration using geographic information systems, and (5) validation of the wellbeing opportunity index for children and adolescents. REDibuja will implement methodologies that until now are little used to facilitate political decisions in our regional context. This process and results could be transferred for assessment and decision-making in Latin America and low- and middle-income countries in other regions.

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The production of ornamentals is an economic activity of great interest, particularly the production of Lilium. This plant is very attractive for its color and shapes; however, the quality of its flower and its shelf life can decrease very fast. Therefore, it is of the utmost importance to develop techniques that allow for increasing both flower quality and shelf life. Nanotechnology has allowed for the use of various materials with unique characteristics. These materials can induce a series of positive responses in plants, among which the production of antioxidant compounds stands out. The objective of this study was to determine the impact of the application of silicone nanoparticles (SiO2 NPs) on the quality, shelf life, and antioxidant status of Lilium. For this, different concentrations of SiO2 NPs (0, 200, 400, 600, 800, and 1000 mg L-1) were applied in two ways, foliar and soil, as two independent experiments. The contents of enzymatic (superoxide dismutase, glutathione peroxidase, catalase, ascorbate peroxidase, and phenylalanine ammonia lyase) and non-enzymatic (phenols, flavonoids, and glutathione) antioxidant compounds, the mineral content, flower quality, and shelf life were analyzed. The results showed that the application of SiO2 NPs through the foliar method induced a greater flowers' shelf life (up to 21.62% more than the control); greater contents of Mg, P, and S (up to 25.6%, 69.1%, and 113.9%, respectively, compared to the control); more photosynthetic pigment (up to 65.17% of total chlorophyll); more glutathione peroxidase activity (up to 69.9%); more phenols (up to 25.93%); and greater antioxidant capacity as evaluated by the DPPH method (up to 5.18%). The use of SiO2 NPs in the production of Lilium is a good alternative method to increase flower quality and shelf life.

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Plant biostimulants are compounds, living microorganisms, or their constituent parts that alter plant development programs. The impact of biostimulants is manifested in several ways: via morphological, physiological, biochemical, epigenomic, proteomic, and transcriptomic changes. For each of these, a response and alteration occur, and these alterations in turn improve metabolic and adaptive performance in the environment. Many studies have been conducted on the effects of different biotic and abiotic stimulants on plants, including many crop species. However, as far as we know, there are no reviews available that describe the impact of biostimulants for a specific field such as transcriptomics, which is the objective of this review. For the commercial registration process of products for agricultural use, it is necessary to distinguish the specific impact of biostimulants from that of other legal categories of products used in agriculture, such as fertilizers and plant hormones. For the chemical or biological classification of biostimulants, the classification is seen as a complex issue, given the great diversity of compounds and organisms that cause biostimulation. However, with an approach focused on the impact on a particular field such as transcriptomics, it is perhaps possible to obtain a criterion that allows biostimulants to be grouped considering their effects on living systems, as well as the overlap of the impact on metabolism, physiology, and morphology occurring between fertilizers, hormones, and biostimulants.

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OBJECTIVE: To conduct a comprehensive review of scientific publications related to mental pain and suicide risk in order to deepen relevant aspects to guide clinical interventions. METHOD: Using a text analysis tool, we collected the terms most frequently linked with that situation in published results of research using various tools to evaluate mental pain or psychache. DISCUSSION: We propose clinical interventions for the clinical conditions most commonly associated with mental pain.

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BACKGROUND: This study aimed to determine conditional dependence relationships of variables that contribute to psychological vulnerability associated with suicide risk. A Bayesian network (BN) was developed and applied to establish conditional dependence relationships among variables for each individual subject studied. These conditional dependencies represented the different states that patients could experience in relation to suicidal behavior (SB). The clinical sample included 650 mental health patients with mood and anxiety symptomatology. RESULTS: Mainly indicated that variables within the Bayesian network are part of each patient's state of psychological vulnerability and have the potential to impact such states and that these variables coexist and are relatively stable over time. These results have enabled us to offer a tool to detect states of psychological vulnerability associated with suicide risk. CONCLUSION: If we accept that suicidal behaviors (vulnerability, ideation, and suicidal attempts) exist in constant change and are unstable, we can investigate what individuals experience at specific moments to become better able to intervene in a timely manner to prevent such behaviors. Future testing of the tool developed in this study is needed, not only in specialized mental health environments but also in other environments with high rates of mental illness, such as primary healthcare facilities and educational institutions.

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Tomato is one of the most economically important vegetables worldwide and is constantly threatened by various biotic and abiotic stress factors reducing the quality and quantity in the production of this crop. As an alternative to mitigate stress in plants, carbon nanomaterials (CNMs) have been used in agricultural areas. Therefore, the objective of the present work was to evaluate the antioxidant responses of tomato seedlings to the application via foliar and drench of carbon nanotubes (CNTs) and graphene (GP). Different doses (10, 50, 100, 250, 500, and 1000 mg L-1) and a control were evaluated. The results showed that the fresh and dry root weight increased with the application of CNMs. Regarding the antioxidant responses of tomato seedlings, the application of CNMs increased the content of phenols, flavonoids, ascorbic acid, glutathione, photosynthetic pigments, activity of the enzyme's ascorbate peroxidase, glutathione peroxidase, catalase, and phenylalanine ammonia lyase as well as the content of proteins. Therefore, the use of carbon-based nanomaterials could be a good alternative to induce tolerance to different stress in tomato crop.

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Tomato fruit is rich in antioxidant compounds such as lycopene and ß-carotene. The beneficial effects of the bioactive compounds of tomato fruit have been documented as anticancer activities. The objective of this research was to determine whether arsenic (As) causes changes in the content of antioxidant compounds in tomato fruits and whether Silicon nanoparticles (SiO2 NPs) positively influence them. The effects on fruit quality and non-enzymatic antioxidant compounds were determined. The results showed that As decreased the oxide-reduction potential (ORP), while lycopene and ß-carotene were increased by exposure to As at a low dose (0.2 mg L-1), and proteins and vitamin C decreased due to high doses of As in the interaction with SiO2 NPs. A dose of 250 mg L-1 of SiO2 NPs increased glutathione and hydrogen peroxide (H2O2), and phenols decreased with low doses of As and when they interacted with the NPs. As for the flavonoids, they increased with exposure to As and SiO2 NPs. The total antioxidant capacity, determined by the ABTS (2,2´-azino-bis[3-ethylbenzthiazolin-6-sulfonic acid]) test, showed an increase with the highest dose of As in the interaction with SiO2 NPs. The application of As at low doses induced a greater accumulation of bioactive compounds in tomato fruit; however, these compounds decreased in high doses as well as via interaction with SiO2 NPs, indicating that there was an oxidative burst.

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Sulfur is an essential element in determining the productivity and quality of agricultural products. It is also an element associated with tolerance to biotic and abiotic stress in plants. In agricultural practice, sulfur has broad use in the form of sulfate fertilizers and, to a lesser extent, as sulfite biostimulants. When used in the form of bulk elemental sulfur, or micro- or nano-sulfur, applied both to the soil and to the canopy, the element undergoes a series of changes in its oxidation state, produced by various intermediaries that apparently act as biostimulants and promoters of stress tolerance. The final result is sulfate S+6, which is the source of sulfur that all soil organisms assimilate and that plants absorb by their root cells. The changes in the oxidation states of sulfur S0 to S+6 depend on the action of specific groups of edaphic bacteria. In plant cells, S+6 sulfate is reduced to S-2 and incorporated into biological molecules. S-2 is also absorbed by stomata from H2S, COS, and other atmospheric sources. S-2 is the precursor of inorganic polysulfides, organic polysulfanes, and H2S, the action of which has been described in cell signaling and biostimulation in plants. S-2 is also the basis of essential biological molecules in signaling, metabolism, and stress tolerance, such as reactive sulfur species (RSS), SAM, glutathione, and phytochelatins. The present review describes the dynamics of sulfur in soil and plants, considering elemental sulfur as the starting point, and, as a final point, the sulfur accumulated as S-2 in biological structures. The factors that modify the behavior of the different components of the sulfur cycle in the soil-plant-atmosphere system, and how these influences the productivity, quality, and stress tolerance of crops, are described. The internal and external factors that influence the cellular production of S-2 and polysulfides vs. other S species are also described. The impact of elemental sulfur is compared with that of sulfates, in the context of proper soil management. The conclusion is that the use of elemental sulfur is recommended over that of sulfates, since it is beneficial for the soil microbiome, for productivity and nutritional quality of crops, and also allows the increased tolerance of plants to environmental stresses.

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Objective: To identify clinical and sociodemographic factors that increase or decrease suicidal risk in a clinical sample of subjects seeking mental health care. Method: A cross-sectional study was performed at three health centers in Santiago, Chile. The Parental Bonding Instrument (PBI), Depressive Experience Questionnaire (DEQ), Outcome Questionnaire (OQ-45.2), Reasons for Living Inventory (RFL), and State Trait Anger Expression Inventory (STAXI-2), in addition to a sociodemographic survey, were applied to 544 participants (333 with suicidal behavior and 211 without current suicidal behavior). Through hierarchical clustering analysis, participants were grouped by similarity regarding suicidal risk. Then, a regression analysis was performed using the Least Absolute Shrinkage and Selection Operator (LASSO) technique, and factors that decrease or increase suicide risk (SR) were identified for each cluster. Results: The resultant clusters were grouped mainly by the age of participants. The most important protective factor was having confidence in one's own coping skills in difficult situations. Relevant risk factors were major depressive disorder (MDD), poor anger management, and difficulties in interpersonal relationships. Conclusions: Suicidal risk manifests differently throughout the life cycle, and different types of bonds may protect from or increase risk of suicide.

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Biostimulants are materials that when applied in small amounts are capable of promoting plant growth. Nanoparticles (NPs) and nanomaterials (NMs) can be considered as biostimulants since, in specific ranges of concentration, generally in small levels, they increase plant growth. Pristine NPs and NMs have a high density of surface charges capable of unspecific interactions with the surface charges of the cell walls and membranes of plant cells. In the same way, functionalized NPs and NMs, and the NPs and NMs with a corona formed after the exposition to natural fluids such as water, soil solution, or the interior of organisms, present a high density of surface charges that interact with specific charged groups in cell surfaces. The magnitude of the interaction will depend on the materials adhered to the corona, but high-density charges located in a small volume cause an intense interaction capable of disturbing the density of surface charges of cell walls and membranes. The electrostatic disturbance can have an impact on the electrical potentials of the outer and inner surfaces, as well as on the transmembrane electrical potential, modifying the activity of the integral proteins of the membranes. The extension of the cellular response can range from biostimulation to cell death and will depend on the concentration, size, and the characteristics of the corona.

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OBJECTIVE: To identify clinical and sociodemographic factors that increase or decrease suicidal risk in a clinical sample of subjects seeking mental health care. METHOD: A cross-sectional study was performed at three health centers in Santiago, Chile. The Parental Bonding Instrument (PBI), Depressive Experience Questionnaire (DEQ), Outcome Questionnaire (OQ-45.2), Reasons for Living Inventory (RFL), and State Trait Anger Expression Inventory (STAXI-2), in addition to a sociodemographic survey, were applied to 544 participants (333 with suicidal behavior and 211 without current suicidal behavior). Through hierarchical clustering analysis, participants were grouped by similarity regarding suicidal risk. Then, a regression analysis was performed using the Least Absolute Shrinkage and Selection Operator (LASSO) technique, and factors that decrease or increase suicide risk (SR) were identified for each cluster. RESULTS: The resultant clusters were grouped mainly by the age of participants. The most important protective factor was having confidence in one's own coping skills in difficult situations. Relevant risk factors were major depressive disorder (MDD), poor anger management, and difficulties in interpersonal relationships. CONCLUSIONS: Suicidal risk manifests differently throughout the life cycle, and different types of bonds may protect from or increase risk of suicide.

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Silicon is an essential nutrient for humans, additionally is beneficial for terrestrial plants. In plants Si enhances tolerance to different types of stress; in humans, it improves the metabolism and increases the strength of skeletal and connective tissues as well as of the immune system. Most of the Si intake of humans come from edible plants creating a double benefit: first, because the absorption of Si increases the antioxidants and other phytochemicals in plants, thereby increasing its functional value, and second because the higher concentration of Si in plants increases intake in human consumers. Therefore, it is desirable to raise the availability of Si in the human diet through the agronomic management of Si accumulator species, such as corn, wheat, rice, soybeans, and beans. But also in such species as tomatoes, carrots, and other vegetables, whose per capita consumption has increased. However, there are few systematized recommendations for the application and management of Si fertilizers based on the physicochemical factors that determine their availability, absorption, transport, and deposition in cells and tissues. This study presents updated information about edaphic and plant factors, which determine the absorption, transport, and deposition rates in edible organs. The information was integrated into an estimated dynamic model that approximates the processes previously mentioned in a model that represents a tomato crop in soil and soilless conditions. In the model, on the other hand, was integrated the available information about key environmental factors related to Si absorption and mobilization, such as the temperature, pH, and soil organic matter. The output data of the model were compared against information collected in the literature, finding an adequate adjustment. The use of the model for educational or technical purposes, including the possibility of extending it to other horticultural crops, can increase the understanding of the agronomic management of Si in plants.

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Chitosan is a natural polymer, which has been used in agriculture to stimulate crop growth. Furthermore, it has been used for the encapsulation of nanoparticles in order to obtain controlled release. In this work, the effect of chitosan-PVA and Cu nanoparticles (Cu NPs) absorbed on chitosan-PVA on growth, antioxidant capacity, mineral content, and saline stress in tomato plants was evaluated. The results show that treatments with chitosan-PVA increased tomato growth. Furthermore, chitosan-PVA increased the content of chlorophylls a and b, total chlorophylls, carotenoids, and superoxide dismutase. When chitosan-PVA was mixed with Cu NPs, the mechanism of enzymatic defense of tomato plants was activated. The chitosan-PVA and chitosan-PVA + Cu NPs increased the content of vitamin C and lycopene, respectively. The application of chitosan-PVA and Cu NPs might induce mechanisms of tolerance to salinity.

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Introducción La biopsia percutánea con guía estereotáxica digital (bed) ha permitido disminuir el número de cirugías innecesarias y planificar con mejores resultados las biopsias y cirugías radioquirúrgicas. Objetivos El objetivo de este trabajo fue analizar la tasa de subestimación de la punción biopsia percutánea con guía estereotáxica digital y correlacionar la imagen mamográfica con la histopatología. Material y método Se evaluaron 247 pacientes con lesiones mamarias subclínicas diagnosticadas por mamografía y sometidas a una bed (suros) durante el período mayo 2013 a diciembre 2015. Se registró de cada paciente la edad, clasificación de bi-rads, la morfología radiológica de las lesiones, los informes histopatológicos de las bed y de posteriores biopsias y/o cirugías radioquirúrgicas (bp/cxrdq). Se analizaron 237 biopsias (Bp). La edad promedio fue de 52 años. De 237 Bp realizadas, obtuvimos 168 lesiones benignas, 25 lesiones de alto riesgo histológico (larh) y 44 malignas. La sensibilidad de las bed fue del 97,7% y la especificidad del 100%; la tasa de subestimación del método fue del 4% para larh y del 26% para cdis. Las lesiones radiológicas predominantes fueron las microcalcificaciones. Conclusiones La bed ha demostrado ser un excelente método de diagnóstico, con múltiples ventajas respecto de la bprdq, con una buena correlación histopatológica y muy baja tasa de subestimación en larh

Introduction Vacuum-assisted stereotactic breast biopsy (dvab) allowed to reduce the number of unnecessary surgeries and plan with better results biopsies and radiosurgical surgeries. Objectives The aim was to analyze the underestimation rate of dvab and correlate the mammographic image with histopathology. Materials and method 247 patients with subclinical breast lesions diagnosed by mammography and subjected to a dvab (suros) during the period May 2013 - December 2015 were evaluated. The age of each patient, bi-rads classification, radiological morphology of lesions, dvab histopathologic reports and subsequent biopsies and/or radiosurgical surgeries (bp/cxrdq) were registered. 237 biopsies were analyzed. The average age was 52 years. Of 237 Bp realized, we obtained 168 benign lesions (lb), 25 high risk histologically lesions (hrhl) and 44 malignant lesions (lm). The dvab sensitivity and specificity was 97.7% and 100%, respectively. The rate of underestimation of the method was 4% for hrhl and 26% for dcis. Microcalcifications were the predominant radiological lesions. Conclusions The dvab has proved to be an excellent method of diagnosis, with multiple advantages over the BpRDQ, with a good correlation histopathological and very low rate of underestimation in hrhl.

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Resumen Se aborda en este articulo la perspectiva teórica y resultados de una investigación realizada en la ciudad de Córdoba (2014-2015) acerca de las prácticas de apropiación juvenil de computadoras personales (netbook), provistas a estudiantes de escuelas secundarias de gestión pública, a través del Programa Conectar Igualdad (PCI). Uno de los propósitos del PCI es la disminución de las diferencias entre los jóvenes que poseen acceso a las tecnologías digitales y quienes no lo tienen, para favorecer la inclusión digital. Los resultados del estudio muestran que para el caso de la ciudad de Córdoba, esta meta fue alcanzada ampliamente. Considerando integralmente las políticas públicas en el tema, como investigadores nos interesa observar el lugar que ocupan las netbook en la vida cotidiana de los jóvenes, describir las modalidades que asumen las prácticas de apropiación e identificar los factores que las condicionan, generando modos de apropiación diferenciada entre diversos grupos. La definición de apropiación que sostenemos presupone que la disponibilidad y el acceso son condiciones necesarias pero no suficientes. Otra de las dimensiones de la apropiación que es preciso considerar es la referida a las competencias tecnológicas. Hemos observado que muchos jóvenes se declaran expertos en el uso de diversas aplicaciones informáticas, fundamentalmente aquellas vinculadas al entretenimiento y las redes sociales. Pero muchos otros usos, en particular los referidos al aprendizaje y la producción de conocimiento, son desconocidos y poco explorados por ellos. Identificamos que es en la escuela donde están adquiriendo, incipientemente aún, aprendizajes alternativos a los propuestos por el mercado.

Resumo O presente artigo aborda a perspectiva teórica e os resultados de uma pesquisa realizada na cidade de Córdoba (2014-2015) sobre as práticas de apropriação juvenil de computadores pessoais (netbook), dadas aos estudantes secundaristas de escolas públicas pelo "Programa Conectar Igualdad" (PCI). Um dos propósitos do PCI é a diminui- ção das diferenças entre os jovens que possuem acesso às tecnologias digitais e os que não a tem, a fim de favorecer sua inclusão digital. Os resultados do estudo mostram que, para o caso da cidade de Córdoba, esta meta foi amplamente alcançada. Considerando integralmente as políticas públicas sobre o tema, como pesquisadores nos interessa observar o lugar que os netbooks ocupam na vida cotidiana dos jovens, descrever as modalidades que assumem as práticas de apropriação e identificar os fatores que as condicionam, gerando modos de apropriação diferenciados entre os diversos grupos. A definição de apropriação que sustentamos pressupõe que a disponibilidade e o acesso são condições necessárias, mas, não são suficientes. Outra dimensão da apropriação que é preciso considerar refere-se às competências tecnológicas. Observamos que muitos jovens se declaram experts no uso de várias aplicações informáticas, fundamentalmente àquelas vinculadas ao entretenimento e às redes sociais. Entretanto, muitos outros usos, em particular os referidos à aprendizagem e à produção de conhecimento, são desconhecidos e pouco explorados por eles. Identificamos que é na escola que os jovens estão adquirindo, ainda que incipientemente, aprendizagens alternativas às propostas pelo mercado.

Abstract This article discusses the theoretical perspective and the results of a research carried out in the city of Córdoba (2014-2015), on the may in which secondary school students make their appropriation process towards the utilization of personal computers provided by the PCI (Programa Conectar Igualdad). One of the main goals of the PCI is to diminish who have access to digital technologies and those who do not, in order to digital enlarge the number of students reached by digital inclusion. Taking into account the public policies in the matter, as researches, we are interested in observing the place these computers have in youngsters everyday life. Moreover, we are interested in describing the different ways of appropriation and identifying the factors which affect this practice. Nevertheless, the definition of the term appropriation that we sustain presupposes that the availability and access to technological tools are important matters, but then are not sufficient. It is also necessary to take into account the technological competences with is one of the many dimensions that constitutes the concept of appropriations. Generally, youngsters declare themselves to be experts on the use of a diverse variety of technological applications, mainly those ones related to entertainment and social networks. However, youngsters somehow ignore and barely explore the uses of these applications with are related to learning and the production of knowledge. Moreover, we notice that students acquire these types of alternative learning at school and these learning differ from those ones with are promoted by the market.

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Selenium is an element that must be considered in the nutrition of certain crops since its use allows the obtaining of biofortified crops with a positive impact on human health. The objective of this review is to present the information on the use of Se and S in the cultivation of plants of the genus Allium. The main proposal is to use Allium as specialist plants for biofortification with Se and S, considering the natural ability to accumulate both elements in different phytochemicals, which promotes the functional value of Allium. In spite of this, in the agricultural production of these species, the addition of sulfur is not realized to obtain functional foods and plants more resistant; it is only sought to cover the necessary requirements for growth. On the other hand, selenium does not appear in the agronomic management plans of most of the producers. Including S and Se fertilization as part of agronomic management can substantially improve Allium crop production. Allium species may be suitable to carry out biofortification with Se; this practice can be combined with the intensive use of S to obtain crops with higher production and sensory, nutritional, and functional quality.

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