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1.
J Sci Educ Technol ; 30(5): 658-677, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33758488

RESUMO

Science and Engineering (S&E) fairs are a valuable educational activity and are believed to increase students' engagement and learning in science and engineering. However, due to differences in resources, many schools do not implement fairs to achieve these benefits for their students. This study reports the findings of a program intended to increase the participation of students from low-achieving and under-resourced schools in a regional fair program that feeds into the international fair competition. We found that the number of schools and projects participating in our regional fair increased dramatically since the start of the program. Teachers had mostly positive expectations for the project and expressed buy-in for the effort the project would take. They recruited a diverse pool of students to participate in the school fairs. Quasi-experimental methods allowed us to explore the impact of completing S&E fairs on student gains on science self-efficacy, interest and value perceptions. Controlling for pre-existing differences in these attitudes, we found that students not completing projects showed declines in their science attitudes during the year. Students who completed projects maintained similar attitudes, while those whose projects advanced to the regional fair had substantial gains on all three variables. It is unknown whether this gain can be attributed to the experience of engaging with a quality project, from being the kind of student who completes a quality project, or some other factor. Future research with greater experimental control could address these questions.

2.
Chem Commun (Camb) ; 57(20): 2551-2554, 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33585852

RESUMO

A new naphthylsalophen and its 3 : 2 ligand-to-lanthanide sandwich-type complexes were isolated. When excited at 380 nm, the complexes display the characteristic metal-centred emission for NdIII, ErIII and YbIII. Upon 980 nm excitation, in mixed lanthanide and the Er complexes, Er-centred upconversion emission at 543 and 656 nm is observed, with power densities as low as 2.18 W cm-2.

3.
Chem Commun (Camb) ; 54(83): 11693-11696, 2018 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-30177989

RESUMO

A salophen ligand derivative incorporating naphthalene (naphthylsalophen = [H2L]) and the corresponding uranyl (UO22+) complex have been synthesized and characterized both in solution and the solid-state. A hydrogen bonding uranyl tetramer and the electrochemical analysis of [H2L] and UO2[L] are described.

4.
Physiol Behav ; 172: 24-30, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-27422674

RESUMO

Prenatal stress has been linked to deficits in neurological function including deficient social behavior, alterations in learning and memory, impaired stress regulation, and susceptibility to adult disease. In addition, prenatal environment is known to alter cardiovascular health; however, limited information is available regarding the cerebrovascular consequences of prenatal stress exposure. Vascular disturbances late in life may lead to cerebral hypoperfusion which is linked to a variety of neurodegenerative and psychiatric diseases. The known impact of cerebrovascular compromise on neuronal function and behavior highlights the importance of characterizing the impact of stress on not just neurons and glia, but also cerebrovasculature. Von Willebrand factor has previously been shown to be impacted by prenatal stress and is predictive of cerebrovascular health. Here we assess the impact of prenatal stress on von Willebrand factor and related angiogenic factors. Furthermore, we assess the potential protective effects of concurrent anti-depressant treatment during in utero stress exposure on the assessed cerebrovascular endpoints. Prenatal stress augmented expression of von Willebrand factor which was prevented by concurrent in utero escitalopram treatment. The functional implications of this increase in von Willebrand factor remain elusive, but the presented data demonstrate that although prenatal stress did not independently impact total vascularization, exposure to chronic stress in adulthood decreased blood vessel length. In addition, the current study demonstrates that production of reactive oxygen species in the hippocampus is decreased by prenatal exposure to escitalopram. Collectively, these findings demonstrate that the prenatal experience can cause complex changes in adult cerebral vascular structure and function.


Assuntos
Citalopram/farmacologia , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Estresse Psicológico/metabolismo , Fator de von Willebrand/biossíntese , Fatores Etários , Tonsila do Cerebelo/irrigação sanguínea , Proteínas Angiogênicas/biossíntese , Animais , Citalopram/administração & dosagem , Feminino , Hipocampo/irrigação sanguínea , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Córtex Pré-Frontal/irrigação sanguínea , Gravidez , Ratos , Espécies Reativas de Oxigênio/metabolismo , Estresse Psicológico/patologia
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