3,258 research outputs found
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]
Magnetic properties of GdZn (T = Fe, Co) investigated by X-ray diffraction and spectroscopy
We investigate the magnetic and electronic properties of the GdZn
( = Fe and Co) compounds using X-ray resonant magnetic scattering (XRMS),
X-ray absorption near-edge structure (XANES) and X-ray magnetic circular
dichroism (XMCD) techniques. The XRMS measurements reveal that the
GdCoZn compound has a commensurate antiferromagnetic spin structure
with a magnetic propagation vector =
below the N\'eel temperature ( 5.7 K). Only the Gd ions carry a magnetic moment forming an
antiferromagnetic structure with magnetic representation . For the
ferromagnetic GdFeZn compound, an extensive investigation was
performed at low temperature and under magnetic field using XANES and XMCD
techniques. A strong XMCD signal of about 12.5 and 9.7 is observed
below the Curie temperature ( 85 K) at the Gd- and edges,
respectively. In addition, a small magnetic signal of about 0.06 of the
jump is recorded at the Zn -edge suggesting that the Zn 4 states are spin
polarized by the Gd 5 extended orbitals
Políticas públicas na agroindústria do dendê na visão do produtor.
bitstream/item/63648/1/Oriental-Doc222.PD
Armazenabilidade de sementes de Coffea canephora Pierre colhidas em diferentes estádios de maturação e submetidas a diferentes métodos de secagem.
A lenta e desuniforme germinação de sementes de cafeeiro aliadas ao seu baixo potencial de armazenamento, dificultam a obtenção de mudas uniformes e bem desenvolvidas. Apesar dos esforços das pesquisas as causas da lenta germinação ou baixa armazenabilidade das sementes continuam obscuras. Para a produção de sementes de cafeeiro é recomendada à colheita dos frutos no estádio cereja, no entanto pesquisas têm demonstrado que estas sementes já adquirem a sua máxima capacidade germinativa entre os estádios verde cana e cereja e que sementes completamente maduras, podem não ter o máximo potencial de armazenamento ou maior tolerância à desidratação devido à provável iniciação do processo de germinação já no final do processo de desenvolvimento. Assim, o presente trabalho foi realizado com o objetivo de investigar os efeitos do estádio de desenvolvimento e do método de secagem sobre a germinabilidade e a armazenabilidade de sementes de cafeeiro. Sementes foram processadas a partir de frutos de Coffea canephora Pierre, cultivar Apoatã IAC2258, colhidos no estádio cereja e verde cana e submetidas a três métodos de secagem (sem secagem, secagem lenta à sombra e secagem rápida em secador estacionário). Após quatro meses de armazenamento sob temperatura de 10ºC em embalagens herméticas, foram avaliados a qualidade fisiológica e o vigor das sementes por meio dos testes de germinação, de protrusão radicular, de matéria seca de plântulas, de emergência em bandejas, de índice de velocidade de emergência, de condutividade elétrica e de viabilidade pelo teste de tetrazólio. Analisando-se os resultados pode-se concluir que sementes de Coffea canephora L. apresentam maior capacidade de armazenamento quando colhidas no estádio cereja e são armazenadas úmidas. Além disto, em ambos estádios de maturação, as sementes apresentam desempenhos fisiológicos semelhantes, após quatro meses de armazenamento, quando são submetidas uma secagem lenta. A secagem rápida é prejudicial à qualidade fisiológica de sementes de Coffea canephora L
Application of Anaerobic and Ozonation Processes in the Landfill Leachate Treatment
The optimization of leachate treatment was investigated as well as the configuration of a biological-ozonation process. The leachate used for the experiments was diluted to 1/5 with tap water and treated anaerobically. The anaerobic effluent and the raw leachate were treated with ozone in order to increase their biodegradability getting the minimum organic matter removal. Both were submitted to the ozonation process, applying a constant ozone dose and varying the contact time. The ozonation of raw leachate produced a decrease of COD and BOD5 concentrations as well as BOD5/COD ratios, applying an ozone dose of 38.72 mg/L•min and contact times between 15 and 60 minutes. Ozonation as a pre-treatment process to the biological system did not improve the biodegradability of the raw leachate. The anaerobic effluent from the reactor fed with leachate diluted to 1/5, was subjected to an ozone dose of 34.99 mg/L•min and applying different contact times. BODf values increased from 74.75 up to 1220 mg/L and BODf/COD ratios reached values higher than 1. Then, the application of ozone to the anaerobic effluent led to the improvement of the biodegradability of the leachate as well as the BODf/COD ratio for all the contact times used
Produção e composição química de cultivares de capim elefante no município de Altamira-PA.
bitstream/item/57537/1/Belem-BP1.pd
Severe intracranial haemorrhage in neonatal alloimmune thrombocytopenia
Neonatal alloimmune thrombocytopenia is a rare (1/1000-5000 births) life-threatening disorder, caused by fetomaternal incompatibility for a fetal human platelet alloantigen inherited from the father, with production of maternal alloantibodies against fetal platelets, leading to severe thrombocytopenia and potential bleeding. Intracranial haemorrhage is the most feared complication. This report presents the case of a term newborn infant, born from caesarean section after a normal pregnancy, presenting signs of skin bleeding with different ages. Obstetric history included a previous spontaneous abortion after amniocentesis. Severe thrombocytopenia (4×10(9)/l platelets) was found and brain ultrasound showed multiple intracranial haemorrhages. Human platelet antigen (HPA) phenotyping showed maternal negative HPA-1a and paternal positive HPA-1a platelets. Strongly positive anti-HPA-1a and weakly positive anti-human leukocyte antigen class I alloantibodies were found in the mother. Multiple platelet transfusions, intravenous immunoglobulin and corticosteroid were given but favourable response was accomplished only after a compatible platelet transfusion. Brain MRI showed multiple subacute and chronic haemorrhages
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