Ground-state configurations in ferromagnetic nanotori

Magnetization ground states are studied in toroidal nanomagnets. The energetics associated to the ferromagnetic, vortex and onion-like configurations are explicitly computed. The analysis reveals that the vortex appears to be the most prominent of such states, minimizing total energy in every torus with internal radius $r\gtrsim10\,{\rm nm}$ (for Permalloy). For $r\lesssim10\,{\rm nm}$ the vortex remains the most favorable pattern whenever $R/\ell_{ex}\gtrsim1.5$ ($R$ is the torus external radius and $\ell_{ex}$ is the exchange length), being substituted by the ferromagnetic state whenever $R/\ell_{ex}\lesssim1.5$.Comment: 16 pages, 9 figures, 3 apendices, Revtex forma

Relational Operant Skills Training Increases Standardized Matrices Scores in Adolescents: A Stratified Active-Controlled Trial

In recent years, small-scale studies have suggested that we may be able to substantially strengthen children's general cognitive abilities and intelligence quotient (IQ) scores using a relational operant skills training program (SMART). Only one of these studies to date has included an active Control Condition, and that study reported the smallest mean IQ rise. The present study is a larger stratified active-controlled trial to independently test the utility of SMART training for raising Non-verbal IQ (NVIQ) and processing speed. We measured personality traits, NVIQs, and processing speeds of a cohort of school pupils (aged 12–15). Participants were allocated to either a SMART intervention group or a Scratch computer coding control group, for a period of 3 months. We reassessed pupils’ NVIQs and processing speeds after the 3-month intervention. We observed a significant mean increase in the SMART training group’s (final nexp = 43) NVIQs of 5.98 points, while there was a nonsignificant increase of 1.85 points in the Scratch active-control group (final ncont = 27). We also observed an increase in processing speed across both conditions (final nexp = 70; ncont = 55) over Time. Our results suggest that relational skills training may be useful for improving performance on matrices tasks, and perhaps in future, accelerating children’s progression toward developmental milestones

Effect of different stress treatments on mature green tomatoes (Solanum lycopersicum) to enhance fruit quality

Tomato (Solanum lycopersicum) is a crop of immense economic importance and is grown worldwide. Its fruit is of great nutritional importance as it forms a major part of human diet. Global production of tomato has been estimated at over 153 million metric tonnes in 2009. Consumption of tomato is believed to benefit the heart among other things, as it contains lycopene, one of the most powerful natural antioxidants. The present study was conducted to find the effect of multiple stresses; salt, mannitol, drought and methyl jasmonate on fruit quality of tomato as determined by the evaluation of the content of lycopene, beta-carotene, sucrose and total phenolics. Levels of antioxidants in the tomato after exposure to different stresses during the mature green stage of fruit development were assessed at the Rice Genomics laboratory in the Department of Crop, Soil and Environmental Sciences at the University of Arkansas, USA. Seeds of the tomato cultivar M82 were germinated in the dark for 48 hours. The seedlings were then transplanted into commercial potting soil before being transferred to the greenhouse. The plants were watered every other day until the mature green stage of fruit development (85-90 days post germination). The plants were then divided into five groups and treated with 200mM NaCl, 200 mM mannitol, drought, 100 μM methyl jasmonate and tap water for a period of 72 hours. Afterwards, the stress treatments were removed and fruits allowed to ripen. After ripening the fruits were assayed for lycopene, beta-carotene, phenolics and sucrose content. Tomato plants (S. lycopersicum) subjected to salt stress showed the highest increase in lycopene (2.8x) while for other stresses the increase was by 1.1-1.2x. Beta-carotene content was increased by 2.5-2.7x after salt and drought stress were applied. The highest level of phenolic compounds (2.3x) was observed after treatment with methyl jasmonate. Salt stress increased the sucrose content by 3.2x. Thus the application of stress at the mature green stage of fruit development leads to an increase in bioactive compounds in tomato. This condition has the potential for production of enhanced fruit quality in tomato.Keywords: Tomato (Solanum lycopersicum), stress, antioxidant compounds, lycopene, beta-carotene, sucrose, phenolic

Avaliação hídrica de um latossolo vermelho submetido a sistemas de manejo.

O conteúdo de água em sistemas de preparo do solo são essenciais para avaliar a sustentabilidade agrícola. O objetivo deste estudo foi avaliar os efeitos do teor de água em um Latossolo Vermelho distrófi co sob diferentes sistemas de manejo: 1) Crotalária (Crotalaria juncea), em sistema de semeadura direta (SDC); 2) Milheto (Pennisetum americanum sin. Tiphoydes), em sistema de semeadura direta (SDM); 3) Lablabe (Dolechus lablab), em sistema de semeadura direta (SDL); 4) Semeadura convencional após uma gradagem aradora e duas niveladoras (SSC) e 5) pousio. A propriedade física do solo foi avaliada nas camadas 0,5-0,10 m e 0,15-0,20 m . A curva de retenção de água foi mais influenciada pelo SDM na camada 0,5-0,10 m

Bibliografia de recursos naturais da Amazônia brasileira.

bitstream/item/145920/1/BIBLIOG-RECURSOS-NATURAIS.pd

Portuguese Adaptation of Students Engagement in Schools International Scale (SESIS)

The importance of student’s engagement has been recently pointed out in research. However, there has been a lack of engagement assessment instrument, pertaining psychometric qualities. Objective: This paper presents the Portuguese adaptation of the “Student’s Engagement in School International Scale” (SESIS), drawn up from a12 countries international study (Lam et al., 2012; Lam et al., in press). Method: Psychometric properties of this scale were examined with data from 685 students from different grades (6th, 7th, 9th and 10th), from both sexes, and different regions of the country. Results: Factorial analysis of the results, with varimax rotation, lead to three different factors which explain 50.88% of the variance. The scale integrates the original 33 items, and cognitive, affective and behavioural dimensions. For the external validity study, the relationship between student’s engagement in school results and other school variables — academic performance, self-concept — was considered, and significant relations were observed, as expected. Conclusion: The data presented highlights the qualities of SESIS, as well as its usefulness for research purposes. Suggestion: It is suggested the investigation of the extension of SESIS’s three-dimensionality, in future studiesKeywords: Innovation, technology, research projects, etc. [Arial 10-point, justified alignment]

Towards a Better Understanding of the Factors Associated with Distress in Elderly Cancer Patients: A Systematic Review

his study presents a systematic review of the sociodemographic, clinical, and psychosocial factors associated with distress in elderly cancer patients. Relevant studies were identified using four electronic databases: PubMed, Scopus, Web of Science and ProQuest. Cross-sectional and longitudinal studies exploring factors associated with distress in people over 60 years of age were included and independently assessed using the Joanna Briggs Institute Critical Assessment Checklists. A total of 20 studies met the inclusion criteria. Research showed that being a woman, being single, divorced or widowed, having low income, having an advanced diagnosis, having functional limitations, having comorbidities, and having little social support were factors consistently associated with emotional distress. Data further showed that the impact of age, cancer type, and cancer treatment on symptoms of anxiety and/or depression in elderly patients is not yet well established. The findings of this review suggest that the emotional distress of elderly cancer patients depends on a myriad of factors that are not exclusive, but coexisting determinants of health. Future research is still needed to better understand risk factors for distress in this patient population, providing the resources for healthcare providers to better meet their needs