Remark on the vectorlike nature of electromagnetism and electric charge quantization

In this work we study the structure of electromagnetic interactions and electric charge quantization in gauge theories of electroweak interactions based on semisimple groups. We show that in the standard model of electroweak interactions the structure of electromagnetic interactions is strongly correlated to the quantization pattern of electric charges. We examine these two questions also in all possible chiral bilepton gauge models of electroweak interactions. In all, we can explain the vectorlike nature of electromagnetic interactions and electric charge quantization together demanding nonvanishing fermion masses and anomaly cancellations. ©1999 The American Physical Society.

Leaf and stem anatomy of Vochysiaceae in relation to subfamilial and suprafamilial systematics

Several leaf anatomical features are potentially systematically informative within both the family Vochysiaceae and the order Myrtales, notably tracheoidal idioblasts, mucilage cells and secretory canals. Tracheoids with spiral wall thickenings are present in the mesophyll of most species of Vochysia, and also occur in several other families of Myrtales. Mucilage cells are common in the leaf epidermis in some Vochysiaceae. Secretory ducts are present in the midrib in Salvertia and Vochysia, which are apparently closely related, although Salvertia also shares some leaf anatomical characters with Qualea and Callisthene. Anatomical data do not support the segregation of Ruizterania from Qualea; leaves of R. albiflora leaves are very similar to those of Q. paraensis in venation pattern, and leaf and stem anatomy. Different venation patterns are characteristic of sections within the genus Qualea, but within the large genus Vochysia, leaf anatomy is variable even within a subsection. Amongst other Myrtales, leaf anatomy of Vochysiaceae most closely resembles that of Combretaceae and Onagraceae. © 2002 The Linnean Society of London.

The contribution of biofuels to the sustainability of development in Latin America and the Caribbean

Includes bibliography

Benchmarking the plan of action of the World Summit on the Information Society (WSIS) in Latin America and the Caribbean (version 3.0)

Includes bibliography

Rate of cognitive decline in relation to sex after 60 years-of-age: A systematic review

Some studies have shown differences in specific cognitive ability domains between the sexes at 60 years-of-age. However is important to analyze whether the rate of cognitive decline is also similar between the sexes after this age. The present study examined previously published literature to investigate whether cognitive decline is distinct between men and women after the age of 60 years. A systematic review was carried out with the PubMed, LILACS and PsycINFO databases (2001-2011) using the following search terms: aging, aged, cognitive function, mild cognitive impairment, mental health and cognition. We analyzed longitudinal research that used neuropsychological tests for evaluating cognitive function, showed results separated by sex and that excluded participants with dementia. Elderly women showed better performance in tests of episodic memory, whereas elderly men had a better visuospatial ability. Only one study detected distinct rates of cognitive decline in specific tests between the sexes. Despite differences observed in some domains, most of the studies showed that this rate is similar between the sexes until the age of 80 years. It is unclear whether sex influences the rate of cognitive decline after the age of 80 years. The present review observed that sex does not determine the rate of cognitive decline between 60 and 80 years-of-age. The contextual and cultural factors that involve men and women might determine a distinct decline between them, rather than sex alone. © 2013 Japan Geriatrics Society.

The solid solution between platinum and palladium in nature

Chemical and structural data are reported for platinum-palladium intermediates from two nuggets found at Corrego Bom Sucesso, Minas Gerais, Brazil. Three grains with simple stoichiometries (i.e. PtxPd1 -x with x ∼0.67, ∼0.5 and ∼0.33, which correspond to Pt2Pd, PtPd and PtPd2, respectively) were characterized by single-crystal X-ray diffraction and electron-probe microanalysis. In the absence of single-crystal data it might be tempting to hypothesize that such simple stoichiometries represent distinct mineral species, however structural analyses show that all of the phases are cubic and crystallize in space group Fm3̄m. They are, therefore, natural intermediates in the palladium-platinum solid solution. Reflectance and micro-hardness values are reported for the samples and a comparison with the pure metallic elements made. On the basis of information gained from the chemical and structural characterization it can be concluded that there is a complete solid solution between Pt and Pd in nature. These findings corroborate results from experiments on synthetic compounds. © 2013 The Mineralogical Society.

O projeto Machadianas: Machado de Assis, o Ágora Teatro e a narrativa em cena

Pós-graduação em Artes - IA

Comunicação pública e cidadania: um estudo exploratório na unidade do poupatempo Bauru (SP)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A qualidade dos serviços educacionais e a proteção do código de defesa do consumidor

Pós-graduação em Direito - FCHS

A ética ambiental na produção teórica (dissertações e teses) em educação ambiental no Brasil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A temática ambiental e os cursos superiores de turismo do Estado de São Paulo

Pós-graduação em Educação - IBRC

A dimensão política da educação ambiental: reflexões sobre os trabalhos dos encontros de pesquisa em Educação Ambiental (I, II, III EPEAS)

Pós-graduação em Educação - IBRC

O significado atribuído por licenciandos ao currículo de Biologia numa perspectiva CTSA

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

As TICs no processo de formação de professores de língua estrangeira: crenças de uma professora e de seus alunos de graduação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Renewable energy sources in Latin America and the Caribbean: situation and policy proposals

Includes bibliography