STUDENTS’ PERCEPTIONS OF TEACHER INSTRUMENTAL SUPPORT AS A PREDICTOR OF MOTIVATION IN READING AND MATH AND ACHIEVEMENT FROM SECOND THROUGH TWELFTH GRADE

In this study, relations among students’ perceptions of instrumental help/support from their teachers and their reading and math ability beliefs, subjective task values, and academic grades, were explored from elementary through high school. These relations were examined in an overall sample of 1,062 students from the Childhood and Beyond (CAB) study dataset, a cohort-sequential study that followed students from elementary to high school and beyond. Multi-group structural equation model (SEM) analyses were used to explore these relations in adjacent grade pairs (e.g., second grade to third grade) in elementary school and from middle school through high school separately for males and females. In addition, multi-group latent growth curve (LGC) analyses were used to explore the associations among change in the variables of interest from middle school through high school separately for males and females. The results showed that students’ perceptions of instrumental help from teachers significantly positively predicted: (a) students’ math ability beliefs and reading and math task values in elementary school within the same grade for both girls and boys, and (b) students’ reading and math ability beliefs, reading and math task values, and GPA in middle and high school within the same grade for both girls and boys. Overall, students’ perceptions of instrumental help from teachers more consistently predicted ability beliefs and task values in the academic domain of math than in the academic domain of reading. Although there were some statistically significant differences in the models for girls and boys, the direction and strength of the relations in the models were generally similar for both girls and boys. The implications for these findings and suggestions for future research are discussed.

Connecting the dots: Examining the role of parental beliefs and preschoolers’ affect and engagement in predicting parent-child number exploration during a meaningful math experience

The current study examined the frequency and quality of how 3- to 4-year-old children and their parents explore the relations between symbolic and non-symbolic quantities in the context of a playful math experience, as well as the role of both parent and child factors in this exploration. Preschool children’s numerical knowledge was assessed while parents completed a survey about the number-related experiences they share with their children at home, and their math-related beliefs. Parent-child dyads were then videotaped playing a modified version of the card game War. Results suggest that parents and children explored quantity explicitly on only half of the cards and card pairs played, and dyads of young children and those with lower number knowledge tended to be most explicit in their quantity exploration. Dyads with older children, on the other hand, often completed their turns without discussing the numbers at all, likely because they were knowledgeable enough about numbers that they could move through the game with ease. However, when dyads did explore the quantities explicitly, they focused on identifying numbers symbolically, used non-symbolic card information interchangeably with symbolic information to make the quantity comparison judgments, and in some instances, emphasized the connection between the symbolic and non-symbolic number representations on the cards. Parents reported that math experiences such as card game play and quantity comparison occurred relatively infrequently at home compared to activities geared towards more foundational practice of number, such as counting out loud and naming numbers. However, parental beliefs were important in predicting both the frequency of at-home math engagement as well as the quality of these experiences. In particular, parents’ specific beliefs about their children’s abilities and interests were associated with the frequency of home math activities, while parents’ math-related ability beliefs and values along with children’s engagement in the card game were associated with the quality of dyads’ number exploration during the card game. Taken together, these findings suggest that card games can be an engaging context for parent-preschooler exploration of numbers in multiple representations, and suggests that parents’ beliefs and children’s level of engagement are important predictors of this exploration.

e-Math Workshops : a forum for exchanging experiences of mathematics e-learning at university level

We report here about a series of international workshops on e-learning of mathematics at university level, which have been jointly organized by the three publicly funded open universities in the Iberian Peninsula and which have taken place annually since 2009. The history, achievements and prospects for the future of this initiative will be addressed.

Casi di aggiunta della διαστολή nel codice Vaticano Gr. 1209

El artículo estudia casos de adición de la διαστολή en el Codex Vaticanus gr. 1209. Esta adición puede advertirse, asimismo, en pasajes del Nuevo Testamento y en la Septuaginta donde se utiliza el pronominal ὅτι. Este artículo sostiene que, en los pasajes examinados, la adición responde a propósitos filológicos en lugar de obedecer a razones de lectura. La διαστολή, de hecho, podría ser una especie de firma involuntaria que ayuda a establecer o confirmar los puntos clave antes de que el codex llegase a la Biblioteca Vaticana en 1475.

El diseño de la unidad, la evaluación del aprendizaje y el uso de las calculadoras gráficas ejemplificado en la unidad de ecuaciones de segundo grado

El presente trabajo asume como referente teórico la evaluación del aprendizaje desarrollado en la tesis de doctorado de la autora principal del trabajo (Pérez, 2000), en este sentido la evaluación toma un matiz diferente y está presente desde que planificamos y organizamos el proceso de enseñanza aprendizaje. Paralelamente a esto se muestra el papel y la utilidad de las calculadoras gráficas en la enseñanza de las matemáticas, mostrándose como un recurso más en el quehacer didáctico de los maestros o de una herramienta al servicio de los maestros y alumnos. En el trabajo se muestra cómo lograr el diseño de una unidad en las matemáticas a partir del tema de ecuaciones de segundo grado. Esta propuesta ha sido utilizada en diversos cursos de didáctica de las matemáticas en maestrías de enseñanzas de las ciencias y en cursos independientes para la formación del personal docente, obteniéndose resultados alentadores en el trabajo de los maestros y alumnos.

Learning math through movement: physical education as another alternative

The purpose of this study was to determine the cognitive effects of applying physical recreational activities to two groups of pre-school students, related to mathematics to one of the groups and recreational games to the other.  A total of 27 subjects (13 girls and 14 boys) of 5 and a half and 6 and half years of age participated in the study.  The instrument used was a questionnaire including basic math concepts such as geometry, basic operations with concrete elements, and how to read the clock, based on the topics established by the Costa Rican Ministry of Public Education.  Once the instrument was developed, a plan of physical recreational activities related to math was prepared and applied to the experimental group (pre-school B) for one and a half months, while the other group played recreational games.  Data was analyzed using descriptive and inferential statistics.  Positive and significant effects were found in the physical recreational activity program regarding student performance in 10 of the 12 items that were applied to assess mastery of basic math concepts.  In conclusion, using physical education as another instrument to teach other disciplines represents an excellent alternative for pre-school teachers that try to satisfy the learning needs of children that will soon be attending school.  Using movement as part of guided and planned activities plays an indispensable role in children’s lives; therefore, learning academic subjects should be adapted to their needs to explore and know their environment.

Corrigendum to “The envelope theorem for multiobjective convex programming via contingent derivatives” [J. Math. Anal. Appl. 372 (1) (2010) 197–207]

The aim of this note is to formulate an envelope theorem for vector convex programs. This version corrects an earlier work, “The envelope theorem for multiobjective convex programming via contingent derivatives” by Jiménez Guerra et al. (2010) [3]. We first propose a necessary and sufficient condition allowing to restate the main result proved in the alluded paper. Second, we introduce a new Lagrange multiplier in order to obtain an envelope theorem avoiding the aforementioned error.

Vadr går gränsen?

This article introduces a study concerning parents regulations regarding their child’s participation in social activities. The aim of the study is to examine how many pupils who are not allowed to participate in social activities and some educational elements at school, as for example sports and study tours. The ethnicity and gender perspectives are central for the questions. The implicit aim is to compare the situation among boys and girls with immigrant background in relation to boys and girls with Swedish background. The study contains a quantitative survey among 1193 children, 13 to 15 years old, living in a Swedish middle-sized city. The result from the analysis shows that most of the children are allowed to participate in the activities. However, regarding parental consent to participating in activities the results show that children with immigrant background experience restrictions to a larger extent than others. This result concerns in particular girls with immigrant background. Other significant findings in this study indicate that low-educated parents or/and religious parents have more restrictive norms considering pupils participating in social activities, especially for immigrant girls.

Avaliação preliminar e caracterização morfoagronômica de acessos de feijão-de-metro [Vigna unguiculata (L.) Walp.], cv-gr. Sesquipedalis, no município de Belém, Pará.

O feijão-de-metro é um importante alimento, rico em proteína, vitaminas, fibras e minerais. Muito consumido na região Norte do país, principalmente no estado do Pará, onde é conhecido como feijão-verde. Os materiais utilizados atualmente são os mesmos introduzidos no início do século passado. São comercializadas sementes de uma única cultivar registrada no Registro Nacional de Cultivares (RNC) e de outra que não tem registro. Este trabalho foi realizado com o objetivo de avaliar linhagens de feijão-de-metro em Belém-PA. Foram avaliados 66 acessos no delineamento de blocos de Federer, com duas testemunhas comuns. O experimento foi conduzido na Embrapa Amazônia Oriental, em delineamento de Blocos Federer. Foram avaliados caracteres qualitativos e quantitativos. Com base na produtividade e nos caracteres cor, comprimento e aspecto geral da vagem, importantes para a aceitação comercial, destacaram-se com produtividade superior à 1,6 kg/2m2 os seguintes acessos: China town (PI 487501), TVO 2141 (MNC 1618), CP-74 (PI 487550), Dagupan pangasinan (PI 487486).

Water Stress Reveals Differential Antioxidant Responses Of Tolerant And Non-tolerant Sugarcane Genotypes.

The biochemical responses of the enzymatic antioxidant system of a drought-tolerant cultivar (IACSP 94-2094) and a commercial cultivar in Brazil (IACSP 95-5000) grown under two levels of soil water restriction (70% and 30% Soil Available Water Content) were investigated. IACSP 94-2094 exhibited one additional active superoxide dismutase (Cu/Zn-SOD VI) isoenzyme in comparison to IACSP 95-5000, possibly contributing to the heightened response of IACSP 94-2094 to the induced stress. The total glutathione reductase (GR) activity increased substantially in IACSP 94-2094 under conditions of severe water stress; however, the appearance of a new GR isoenzyme and the disappearance of another isoenzyme were found not to be related to the stress response because the cultivars from both treatment groups (control and water restrictions) exhibited identical changes. Catalase (CAT) activity seems to have a more direct role in H2O2 detoxification under water stress condition and the shift in isoenzymes in the tolerant cultivar might have contributed to this response, which may be dependent upon the location where the excessive H2O2 is being produced under stress. The improved performance of IACSP 94-2094 under drought stress was associated with a more efficient antioxidant system response, particularly under conditions of mild stress.

Neural Mechanisms And Delayed Gastric Emptying Of Liquid Induced Through Acute Myocardial Infarction In Rats.

Background: In pathological situations, such as acute myocardial infarction, disorders of motility of the proximal gut can trigger symptoms like nausea and vomiting. Acute myocardial infarction delays gastric emptying (GE) of liquid in rats. Objective: Investigate the involvement of the vagus nerve, α 1-adrenoceptors, central nervous system GABAB receptors and also participation of paraventricular nucleus (PVN) of the hypothalamus in GE and gastric compliance (GC) in infarcted rats. Methods: Wistar rats, N = 8-15 in each group, were divided as INF group and sham (SH) group and subdivided. The infarction was performed through ligation of the left anterior descending coronary artery. GC was estimated with pressure-volume curves. Vagotomy was performed by sectioning the dorsal and ventral branches. To verify the action of GABAB receptors, baclofen was injected via icv (intracerebroventricular). Intravenous prazosin was used to produce chemical sympathectomy. The lesion in the PVN of the hypothalamus was performed using a 1mA/10s electrical current and GE was determined by measuring the percentage of gastric retention (% GR) of a saline meal. Results: No significant differences were observed regarding GC between groups; vagotomy significantly reduced % GR in INF group; icv treatment with baclofen significantly reduced %GR. GABAB receptors were not conclusively involved in delaying GE; intravenous treatment with prazosin significantly reduced GR% in INF group. PVN lesion abolished the effect of myocardial infarction on GE. Conclusion: Gastric emptying of liquids induced through acute myocardial infarction in rats showed the involvement of the vagus nerve, alpha1- adrenergic receptors and PVN.Fundamento: Distúrbios da motilidade do intestino proximal no infarto agudo do miocárdio podem desencadear sintomas digestivos como náuseas e vômitos. O infarto do miocárdio ocasiona retardo do esvaziamento gástrico (EG) de líquido em ratos. Objetivo: Investigar se existe a influência do nervo vago (VGX), adrenoreceptores α-1, receptores GABAB do sistema nervoso central e participação do núcleo paraventricular (NPV) do hipotálamo no esvaziamento gástrico (EG) e complacência gástrica (CG) em ratos infartados. Métodos: Ratos Wistar (n = 8-15) foram divididos em: grupo infarto (INF), sham (SH) e subdivididos. O infarto foi realizado por ligadura da artéria coronária descendente anterior. A complacência gástrica foi estimada com curvas pressão-volume. Realizada vagotomia por secção dos ramos dorsal e ventral. Para verificar a ação dos receptores GABAB foi injetado baclofeno por via intra ventrículo-cerebral. Simpatectomia química foi realizada com prazosina intravenosa (iv), e na lesão do núcleo paraventricular do hipotálamo foi utilizada corrente elétrica de 1mA/10s, com esvaziamento gástrico determinado por medição da retenção gástrica (% RG) de uma refeição salina. Resultados: Não houve diferença significativa na CG. A vagotomia (VGX) reduziu significativamente a %RG; no grupo INF, o tratamento intra ventrículo-cerebral (ivc) com baclofeno reduziu significativamente a % RG; não houve conclusivamente envolvimento dos receptores GABAB em retardar o EG; o tratamento intravenoso com prazosina reduziu significativamente a %RG no grupo INF. A lesão do NPV aboliu o efeito do infarto do miocárdio no EG. Conclusão: O nervo vago, receptores α-adrenérgicos e núcleo paraventricular estão envolvidos no retardo do esvaziamento gástrico no infarto agudo do miocárdio em ratos.

Jnk And Ikkβ Phosphorylation Is Reduced By Glucocorticoids In Adipose Tissue From Insulin-resistant Rats.

Peripheral insulin resistance (IR) is one of the main side effects caused by glucocorticoid (GC)-based therapies, and the molecular mechanisms of GC-induced IR are not yet fully elucidated. Thus, we aimed to investigate the effects of dexamethasone treatment on the main components of insulin and inflammatory signaling in the adipose tissue of rats. Male Wistar rats received daily injections of dexamethasone (1mg/kg body weight (b.w.), intraperitoneally (i.p.)) for 5 days (DEX), whereas control rats received saline (CTL). The metabolic status was investigated, and the epididymal fat fragments were collected for lipolysis and western blot analyses. The DEX rats became hyperglycemic, hyperinsulinemic, insulin resistant and glucose intolerant, compared with the CTL rats (P<0.05). The basal glycerol release in the fat fragments was 1.5-fold higher in the DEX rats (P<0.05). The phosphorylation of protein kinase B (PKB) at ser(473) decreased by 44%, whereas, the phosphorylation of insulin receptor substrate (IRS)-1 at ser(307) increased by 93% in the adipose tissue of the DEX rats after an oral bolus of glucose (P<0.05). The basal phosphorylation of c-jun-N-terminal kinase (JNK) and inhibitor of nuclear factor kappa-B (IKKβ) proteins was reduced by 46% and 58%, respectively, in the adipose tissue of the DEX rats (P<0.05). This was paralleled with a significant reduction (47%) in the glucocorticoid receptor (GR) protein content in the adipose tissue of the DEX rats (P<0.05). The insulin-resistant status of rats induced by dexamethasone administration have PKB and IRS-1 activity attenuated in epididymal fat without increases in the phosphorylation of the proinflammatory signals JNK and IKKβ.

Antioxidative responses of cell suspension cultures of two Coffea arabica varieties to low aluminum levels at pH 5.8

The effects of aluminum (Al) on the activities of antioxidant enzymes and ferritin expression were studied in cell suspension cultures of two varieties of Coffea arabica, Mundo Novo and Icatu, in medium with pH at 5.8. The cells were incubated with 300 µM Al3+, and the Al speciation as Al3+ was 1.45% of the mole fraction. The activities of superoxide dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST) were increased in Mundo Novo, whereas glutathione reductase (GR) and guaiacol peroxidase (GPOX) activities remained unchanged. SOD, GR, and GST activities were increased in Icatu, while CAT activity was not changed, and GPOX activity decreased. The expression of two ferritin genes (CaFer1 and CaFer2) were analyzed by Real-Time PCR. Al caused a downregulation of CaFER1 expression and no changes of CaFER2 expression in both varieties. The Western blot showed no alteration in ferritin protein levels in Mundo Novo and a decrease in Icatu. The differential enzymes responses indicate that the response to Al is variety-dependent.

Centros de treinamento de ginástica rítmica no Brasil : estrutura e programas

Universidade Estadual de Campinas . Faculdade de Educação Física