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El trabajo se realizó en la FCA-UNR en otoño, invierno y primavera, con el objetivo de evaluar el efecto de los sistemas de producción, forma de sujeción y días de almacenamiento sobre el rendimiento y las pérdidas poscosecha. El ensayo se realizó teniendo en cuenta tres factores: 1) sistemas de producción: invernadero (I), media sombra (MS), manta fl otante (MF) y campo (C), 2) formas de sujeción: manojo (A) y granel (G) y 3) días de almacenamiento. Las variables medidas fueron: rendimiento, materia seca, pérdida de peso por descarte y por agua e índice de color. En las tres épocas, I obtuvo el mayor rendimiento y menor contenido de materia seca. I y MF obtuvieron las menores pérdidas de peso por descarte en otoño; en invierno y otoño aumentan con los días de almacenamiento. I y MF registraron las menores pérdidas de peso por agua en otoño en los días 3 y 6 de almacenamiento. La acelga mostró una tendencia hacia el verde amarillento en MF en otoño, C en invierno e I en primavera, en todos los días de almacenamiento.

Learning environments can benefit from the enactive concept which considers human and technological aspects as coupled together so that interaction is seen as a cycle of perceptually guided actions. Although existing literature reviews have been conducted to address the use of technologies in enactive learning environments, we observe they do not address the relations of technology with core concepts of enactive systems and its social aspects. This paper presents a systematic literature review (SLR) to investigate if and how core concepts of enactive systems are being addressed by learning environments. The SLR was based on the PRISMA protocol, and considered relevant sources of studies (ACM DL, IEEE Xplore, SpringerLink, Scopus, Scielo). We based our analysis on a set of 104 selected articles (from 4514 raised), scrutinized with regards to contextual information, and a proposed set of categories of data related to subjects identified in the studies (e.g., embodiment, technology, social, among others). Our work reveals the types of technologies being used, the types of enactive interactions promoted by the technology-based environments, and the main challenges for a research agenda in the field. Our discussion raised open challenges related to a need for a common vocabulary, a framework to organize concepts in the field, and missing points that deserve further research, such as social aspects of enactive system.

Constructionism has different meanings for what the learner is constructing, a concrete object or an idea, and whether this construction is done through the use of digital technology. In the embodied-based environment created in this study, children carry out or "construct" a series of actions, a performance, which allows them to solve the task of directing an already programmed robot to a particular target. The activity was based on an adaptation of the "Little Red Riding Hood" narrative. Children played the role of rangers (instead of hunters) who had to coordinate their actions in order to help a robot (an mBot characterized as a Robot-Wolf) find Grandma's laboratory, so she could fix its GPS. The children wore boots, which were used to interact with the Robot-Wolf. The main question we addressed was how to create this embodied-based environment for kindergarten children, and how to identify the actions children performed and the concepts they used in this construction. The research was based on the Socially-Aware Design, and the study was conducted in a school setting for kindergarten students. 26 children (11F, 15 M), between 4 and 5 years old, participated in this study. The children's activities were recorded and analysed using the Grounded Theory methodology. The results show that the children's performative sequence of actions is distinct from the hands-on, heads-in processes that are part of classical constructionist environments. For the children, the process and the product of their (body) "dance" were underlying their movement (perceiving and acting), working together so as to accomplish the given task in the environment.

Computing systems have a tremendous influence on how we understand the world. Due to its ubiquity and pervasiveness over the past decade, computing technology has created societal challenges (e.g., related to justice, sustainability, ethics, peace) that demand we reexamine how we design computer-based systems. Drawing on a phenomenological understanding of the human-technology-society relation, this work contributes to the discussion on such challenges and to design practice with a framework we call socially aware design (SAwD). We developed this framework to bring awareness to the human-technology-society relation in the design process. In this paper, we present the framework's main concepts, its underlying worldview, and its methodological base with reference to its origins. We illustrate the framework with design practices that we have experienced in designing systems in diverse situations. We also summarize key aspects of the proposed human-technology-society coupling relevant to the practice of technology design as a social phenomenon, which might open new agendas in the field. [ABSTRACT FROM AUTHOR]

Presents a group of semiotic principles for software design and uses them to show how they explain different educational possibilities. Discusses interface design and describes Theater in the Computer, a software environment for children, to illustrate semiotic-based principle of interface design. (Author/LRW)

Background and Aims: Aleurone is the innermost layer of wheat bran, rich in fiber, minerals, vitamins, phenolic compounds, and betaine. The metabolic effects of aleurone rich foods are still unknown. Our aim was to investigate the effects of consuming a Wheat Aleurone rich diet vs. a Refined Wheat diet for 8 weeks on fasting and postprandial glycemic and lipid metabolism, inflammation, and oxidative stress in overweight/obese individuals.Methods and Results: According to a randomized cross-over study design, 23 overweight/obese individuals, age 56 ± 9 years (M±SD), were assigned to two isoenergetic diet - Wheat Aleurone and Refined Wheat diets - for 8 weeks. The diets were similar for macronutrient composition but different for the aleurone content (40-50 g/day in the Wheat Aleurone diet). After each diet, fasting and postprandial plasma metabolic profile, ferulic acid metabolites and 8-isoprostane concentrations in 24-h urine samples were evaluated. Compared with the Refined Wheat Diet, the Wheat Aleurone Diet increased fasting plasma concentrations of betaine by 15% (p = 0.042) and decreased the excretion of 8-isoprostane by 33% (p = 0.035). Conversely, it did not affect the fasting and postprandial glucose, insulin and triglyceride responses, homocysteine, and C-Reactive Protein concentrations, nor excretion of phenolic metabolites.Conclusion: An 8-week Wheat Aleurone Diet improves the oxidative stress and increases plasma betaine levels in overweight/obese individuals with an increased cardiometabolic risk. However, further studies with longer duration and larger sample size are needed to evaluate the benefits of aleurone-rich foods on glucose and lipid metabolism in individuals with more severe metabolic abnormalities.Clinical Trial Registry Number: NCT02150356, (https://clinicaltrials.gov). [ABSTRACT FROM AUTHOR]

Abstract: Background and aims: Trans-resveratrol (RSV) is a natural compound occurring in different foods and plants, which in vivo is rapidly conjugated with glucuronic acid and sulfate. Despite its demonstrated cardioprotective activity, the bioaccumulation of RSV or its metabolites in cardiac tissue is still unknown. Methods and results: Diabetic rats were randomized to 1, 3 or 6 weeks of RSV treatment at two different doses (1 or 5 mg/kg/day). A dose and time-dependent accumulation was observed, with no detectable levels of RSV metabolites found in heart tissues after 1 week and significant concentrations of RSV-3-sulfate and RSV-3-glucuronide after 6 weeks of treatment (0.05 nmol/g of tissue and 0.01 nmol/g of tissue, respectively). Tissue accumulation of RSV metabolites was accompanied by an improvement of cardiac function in long-term diabetes, when myocardial morpho-functional damage is more evident, with an almost complete recovery of all hemodynamic parameters, at the highest RSV dose. Conclusion: Even if a higher concentration of RSV in tissues cannot be ruled out after constant oral administration, an accumulation coherent with what is usually evaluated in cell based mechanistic studies is largely unattainable and the RSV unconjugated form would not be present in this paradigm. The current investigation provides data on myocardial tissue concentrations of RSV metabolites, after short/medium term RSV treatment. This knowledge constitutes a basic requirement for future studies aimed at reliably defining the molecular pathways underlying RSV-mediated cardioprotective effects and opens up new perspectives for research focused on testing phenolic compounds as adjuvants in degenerative heart diseases. [Copyright &y& Elsevier]

Background and Aims: Resveratrol, the most investigated dietary compound in studies aimed at linking wine consumption to human health, is an extremely minor component of this beverage and it is generally studied in vitro as the unconjugated aglycone at concentrations largely exceeding those found in the human circulatory system after dietary intake. Moreover, following intestinal absorption, trans-resveratrol and its glucoside, which are naturally present in wine and other food sources, are converted to sulphate and glucuronide metabolites. An estrogenic activity has previously been documented for resveratrol, yet nothing is known about the activity of its blood-circulating metabolic derivatives.Methods and Results: Using a yeast two-hybrid detection system relying on the interaction between the ligand-binding domain of the human oestrogen receptors α and β and the human coactivator Tif2, we have systematically examined the oestrogen agonist and antagonist activities of the two main resveratrol forms present in planta (trans-resveratrol and trans-resveratrol-3-O-glucoside) and of the three main metabolites found in human plasma (trans-resveratrol-3-O-sulphate, trans-resveratrol-3-O-glucuronide and trans-resveratrol-4'-O-glucuronide). Only resveratrol-3-O-sulphate was found to display a fairly strong and oestrogen receptor α-preferential antagonistic activity, which was confirmed in a human breast adenocarcinoma cell line containing a luciferase reporter gene under the control of an oestrogen-responsive promoter.Conclusions: We show, for the first time, that resveratrol-3-O-sulphate, but neither of its metabolites, is endowed with anti-estrogenic activity and how human metabolism of phenolic substances plays a pivotal role in modulating their biological effect. [ABSTRACT FROM AUTHOR]

Enormous changes in the computing field are being experienced, altering the way we relate ourselves with computational technology. If computers had at first limited function and presence in our lives, they are now being used everywhere, all the time, for a multitude of purposes and interaction means for interactivity, supporting even our social relations. This shift calls for new ways of evaluating systems, demanding attention not only to usability and accessibility issues but also to the emotional and affective ones. This paper presents a brief review on theory and methods for affective evaluation of computer systems, as a preliminary discussion on the suitability of existing methods for social software applications. The discussion is instantiated in inclusive social software - Vila na Rede, a system developed under a participatory design approach with the purpose of fostering a digital culture among the less favoured segment in the Brazilian society. [ABSTRACT FROM AUTHOR]

Abstract: This study evaluated the absorption and metabolism of milk thistle flavonolignans silychristin, silydianin, silybin and isosilybin isomers (all together known as silymarin) in humans. Fourteen volunteers consumed an extract of milk thistle and urine was collected up to 48h after consumption. Thirty-one metabolites were identified in urine by means of HPLC–MS/MS, monoglucuronides being the most common excreted form, followed by sulphate–glucuronides and diglucuronides, respectively. The excretion of monoglucuronides peaked 2h after consumption, whereas sulphate–glucuronide and diglucuronide excretion peaked at 8h. The bioavailability of milk thistle flavanolignans was 0.45±0.28% (mean±SD). In conclusion, milk thistle flavonolignans are extensively modified after ingestion and recovered in urine as sulpho- and glucuronyl-conjugates, indicating a strong affinity for hepatic phase II enzymes. All future studies (in vitro and in vivo) dealing with the effects of milk thistle should start by considering the modification of its flavonolignans after ingestion by humans. [Copyright &y& Elsevier]

Achalasia is a rare neuromuscular esophageal disorder in children. There are many surgical options to treatment including botulinum toxin (Botox) injections, oral pharmacologic therapies with nitrates and calcium channel blockers, pneumatic dilation (PD), and surgical myotomy (open surgery, endoscopy, laparoscopy and recently robotic approach). In pediatric age, usually, Heller's myotomy is the main choice. Laparoscopic approach is known and standardized. Few robotic have been published. We decided to report our first case to share our experience with scientific community. • Achalasia is a rare neuromuscular esophageal disorder in children. • Heller's myotomy is the main surgical technique and it is associated with fundoplication in the majority of patients. • Robotic assisted surgery reveled a safe and efficient option in pediatric patient. [ABSTRACT FROM AUTHOR]