497 research outputs found

    Esah Etsu Saba: a bronze stool from Nupeland.

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    Este estudo visa enfatizar a iconografia, iconologia, proveniência idade e significância na História da Arte Nupe e nigeriana de um banco de bronze de valor de antiguidade encontrado em Nupeland, Nigéria. São feitas comparações a objetos de arte similares, yoruba e do Benin, bem como a fontes escritas e orais relevantes. Evidências indicam que o banco pertenceu a Etsu Saba, que governou Nupeland entre 1591 e 1600.0 banco é relacionado estilística e morfológicamente a alguns objetos de bronze em Nupeland, Ile-Ife e Benin. Consequentemente, é localizado, tentativamente, no período do séc. XIV ao séc. XVI, no qual aqueles objetos a que está relacionado têm sido datados. Era, provavelmente, uma mercadoria yoruba ou do reino Edo do Benin, destinada a Nupeland

    Iconography, Arts and Design of Metal Sculptures in Nigerian Art Institutions (1980-2011)

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    Nigeria’s rich and diverse artistic heritage dates back to over 2000 years. The earliest noteworthy art pieces, according to scholars, are the finely produced terra-cotta sculptures of the Nok culture, together with bronze heads from Ife dating from the thirteenth century. The bronze plaques, statues and ivory carvings from Benin are generally considered Nigeria’s most important artistic legacies. These sculptures represent those art forms rendered at the period when the impact of foreign aesthetics judgment, ideological and religious influences had not been fully apprehended by the natives, local artisans and craftsmen. With the advent of Western influences, Nigerian art, to a major extent, gave way to modern tendencies: a modern Nigerian art evolved through formal, institution training in art. Sculptural expressions manifested in these institutions are depicted in varied styles, themes, and media such as in cement, metals, marble-stone, fibre-glass, plastics and found-object. With time, a large number of these sculptures were prone to destruction through the effect of weathering and oxidation; particularly, those works produced in metal alloys. This study examines sculptures made of metal alloy in these institutions and looks at some changes that had come up to them as a result of weathering and oxidation over a period of time and proffer some preventive strategies for the metal works. As globalisation affects every facet of human life, the whole world becomes one little village. The visual arts, particularly metal sculpture, are not left out in the benefit of this trend. The study further elucidates on the new aesthetic forms and iconography, styles and themes, materials and techniques that have evolved from the works and positions the genres in historical perspective of modern Nigerian art. Keywords: Iconography, Arts and Design, Metal Sculptures, Nigerian art Institutions

    Parabolic resonances and instabilities in near-integrable two degrees of freedom Hamiltonian flows

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    When an integrable two-degrees-of-freedom Hamiltonian system possessing a circle of parabolic fixed points is perturbed, a parabolic resonance occurs. It is proved that its occurrence is generic for one parameter families (co-dimension one phenomenon) of near-integrable, t.d.o. systems. Numerical experiments indicate that the motion near a parabolic resonance exhibits new type of chaotic behavior which includes instabilities in some directions and long trapping times in others. Moreover, in a degenerate case, near a {\it flat parabolic resonance}, large scale instabilities appear. A model arising from an atmospherical study is shown to exhibit flat parabolic resonance. This supplies a simple mechanism for the transport of particles with {\it small} (i.e. atmospherically relevant) initial velocities from the vicinity of the equator to high latitudes. A modification of the model which allows the development of atmospherical jets unfolds the degeneracy, yet traces of the flat instabilities are clearly observed

    Knowledge-Salvage Practices for Dormant R&D Projects

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    Most successful firms have an abundance of new and old knowledge in their research and development laboratories, and only a fraction is being put into use in new product development. This knowledge is left over from projects that have been killed at different development stages and may actually carry considerable value. In this article, we propose a knowledge bank as a possible solution to preserve and possibly grow this knowledge. It is a self-sustaining institute with minimal or no ongoing effort from the donor company, yet manages the knowledge in a way that protects proprietary interests and actively fosters communication and interchange among sponsoring companies wherever possible. The framework of this structure, as well as how it works, is described here. Specifically, a system dynamics modeling of the knowledge bank is developed, and a simulation study is conducted using VENSIM®. The results confirm the viability of creating such a system in a consortium of organizations

    A influ?ncia entre os estilos de lideran?a sobre o comprometimento organizacional : um estudo em um institui??o de ensino do Munic?pio de Guarabira - PB

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    36 f.A lideran?a possui um importante papel de influenciar e essa habilidade ? necess?ria para que possa elaborar condi??es construtivas na rela??o l?der-liderado. As mudan?as que vem ocorrendo na sociedade e no cen?rio social concede uma reestrutura??o nas institui??es escolares que resultam em formas concretas de gest?o e lideran?a. A import?ncia do papel da lideran?a na escola resultar? em melhoria no desenvolvimento das organiza??es escolares e principalmente a todos que fazem parte da comunidade escolar. Diante disso o presente trabalho tem como objetivo analisar a rela??o entre estilos de lideran?a e comprometimento organizacional dos funcion?rios na Escola Estadual de Ensino Fundamental Deputado Gustavo Amorim do munic?pio de Guarabira ? PB. A pesquisa ? de natureza descritiva e explorat?ria com abordagem quantitativa. Foram aplicados question?rios a todos os funcion?rios da institui??o sendo assim caracterizado um estudo de censo. A coleta de dados foi dividida em dois question?rios, o primeiro realizado com a gest?o da escola. Este question?rio foi elaborado por Almeida (2007) e nele est?o estruturadas as tipologias de lideran?a sendo elas: tra?os, comportamento orientado para tarefas, comportamento orientado para pessoas, contingencial e transformacional. O outro question?rio foi aplicado para os demais funcion?rios da escola sobre a ?tica multidimensional do comprometimento organizacional, aplicando os tr?s indicadores de Meyer e Allen (1991) sendo eles: afetivo, instrumental e normativo. Diante dos resultados obtidos, a gest?o da escola tem predomin?ncia de dois estilos de lideran?a o comportamento orientado para pessoas e a lideran?a transformacional. Constatou-se que os comprometimentos organizacionais dos funcion?rios apresentaram v?nculo afetivo, normativo e instrumental. E por fim encontrou correla??es entre o estilo de lideran?a e o comprometimento, no qual o estilo transformacional teve maior influ?ncia entre os comprometimentos afetivo e normativo

    Rela??o entre comprometimento organizacional e motiva??o no trabalho : um estudo em uma institui??o p?blica do munic?pio de Guarabira ? PB

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    Os aspectos do comportamento humano v?m sendo estudados ao longo dos anos, dessa forma o comprometimento organizacional e a motiva??o no trabalho tem um grande destaque nos estudos da ?rea. O presente estudo tem o objetivo analisar a rela??o entre o comprometimento organizacional e a motiva??o no trabalho dos funcion?rios da Escola Estadual de Ensino Fundamental Deputado Gustavo Amorim no munic?pio de Guarabira-PB. Realizou-se uma pesquisa descritiva e explorat?ria de natureza quantitativa. Foi aplicado um question?rio a todos os funcion?rios da escola caracterizado um estudo de censo. O question?rioera sobre motiva??o do trabalho que ecomprometimento organizacional sobre a ?tica multidimensional dos tr?s indicadores de Meyer e Allen. Diante dos resultados obtidos, observou-se que, no geral, os funcion?rios da escola est?o motivados com o trabalho e os componentes de comprometimento organizacional apresentam v?nculo maior no afetivo e normativo. Foi poss?vel observar, ainda, que a correla??o entre o comprometimento organizacional e a motiva??o do trabalho dos funcion?rios da institui??o foi predominamente negativa entre as vari?veis dos fatores estudados. Constatou-se que os comprometimentos afetivo e normativo apresentaram fraca correla??o com os demais fatores motivacionais, tais resultado sugere que o comprometimento de um funcion?rio n?o passa necessariamente pelo seu estado motivacional. Foram encontradas correla??es positivas entre o comprometimento instrumental e o fator de independ?ncia financeira, provavelmente isso pode ter ocasionado pelo fato da faixa et?ria e tempo de institui??o desses funcion?rios uma vez que eles associam seu comprometimento com as perdas de recompensas que podem ocorrer devido sua sa?da da institui??o

    NASA space station automation: AI-based technology review

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    Research and Development projects in automation for the Space Station are discussed. Artificial Intelligence (AI) based automation technologies are planned to enhance crew safety through reduced need for EVA, increase crew productivity through the reduction of routine operations, increase space station autonomy, and augment space station capability through the use of teleoperation and robotics. AI technology will also be developed for the servicing of satellites at the Space Station, system monitoring and diagnosis, space manufacturing, and the assembly of large space structures

    Plasma level of mannose-binding lectin is associated with the risk of recurrent pregnancy loss but not pregnancy outcome after the diagnosis

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    STUDY QUESTION: Are low or high plasma mannose-binding lectin (p-MBL) levels associated with recurrent pregnancy loss (RPL) and the reproductive and perinatal outcomes before and after RPL? SUMMARY ANSWER: The prevalence of low p-MBL levels was significantly higher in RPL patients, while high levels were significantly less prevalent. No association was found between p-MBL level and reproductive and perinatal outcomes before and after RPL. WHAT IS KNOWN ALREADY: Mannose-binding lectin (MBL) is an important component in the innate immune system. Low p-MBL levels have been associated with RPL, while the correlation with high levels has been poorly studied. Adverse perinatal outcomes are generally more frequent among RPL patients, but reports concerning the association between maternal p-MBL levels and perinatal outcomes, including birth weight (BW) and gestational age (GA), are conflicting. STUDY DESIGN, SIZE, DURATION: This study was a combined cross-sectional and cohort study of 267 RPL patients admitted to the RPL Center of Western Denmark between January 2016 and March 2020. RPL patients were followed until birth of a liveborn child or until end of follow-up, March 2021. A sample of 185 healthy female blood donors of reproductive age was used as a MBL reference group. PARTICIPANTS/MATERIALS, SETTING, METHODS: All RPL patients had ≥3 consecutive pregnancy losses, a regular menstrual cycle and no known significant chromosomal or uterine malformations. At the first consultation, routine blood samples including p-MBL measurement and detailed obstetrical and perinatal information were collected. p-MBL levels in RPL patients were compared to the MBL reference group. A logistic regression analysis adjusted for relevant confounders assessed the association between low p-MBL levels and an unsuccessful reproductive outcome in RPL patients in first pregnancy after admission. Perinatal outcomes before and after RPL were compared between RPL subgroups according to low (≤500 µg/l), intermediate (501–3000 µg/l) and high (>3000 µg/l) p-MBL levels. MAIN RESULTS AND THE ROLE OF CHANCE: Significantly more RPL patients had low p-MBL levels (prevalence proportion ratio (PPR): 1.79, 95% CI: 1.34–2.38) and fewer had high p-MBL levels (PPR: 0.56, 95% CI: 0.40–0.79) compared to the reference group, while the prevalence of intermediate p-MBL level was not different between the groups (PPR: 0.86, 95% CI: 0.69–1.08). In the prospective study, low p-MBL level was not a significant risk factor for a pregnancy loss in the first pregnancy after admission after adjustment for age, BMI and smoking. Neither before nor after the RPL diagnosis were maternal p-MBL levels significantly associated with BW or GA. LIMITATIONS, REASONS FOR CAUTION: Only 161 (60.3%) patients had given birth after RPL during the follow-up period, which limited the possibility to detect clear associations between p-MBL levels and perinatal outcomes after RPL. WIDER IMPLICATIONS OF THE FINDINGS: In agreement with several previous studies, low p-MBL levels are strongly associated with RPL, while this study for the first time documents that high levels may play a protective role, which suggests a causal relationship. We suggest that larger prospective studies evaluate the association between p-MBL levels and RPL prognosis. STUDY FUNDING/COMPETING INTEREST(S): No external funding was received. We acknowledge the Department of Obstetrics and Gynaecology at Aalborg University Hospital for financial support. U.S.K. has reported personal fees from Merck, consulting fees from IBSA Nordic, and a grant from Gedeon Richter, Merck and IBSA Nordic outside of the submitted work. TRIAL REGISTRATION NUMBER: ID from clinicaltrials.gov is NCT04017754

    Influ?ncia de Azteca chartifex (formicidae) na microbiota foliar de Byrsonima sericea.

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    Programa de P?s-Gradua??o em Ecologia de Biomas Tropicais. Departamento de Biodiversidade, Evolu??o e Meio Ambiente, Instituto de Ci?ncias Exatas e Biol?gicas, Universidade Federal de Ouro Preto.A intera??o entre formigas e microrganismos na superf?cie foliar de plantas hospedeiras ? um aspecto negligenciado da ecologia. H? evid?ncias de que a elevada densidade de formigas em um dado habitat foliar pode afetar substancialmente a microbiota, e a rela??o desta com a planta. A quest?o fundamental deste trabalho ? determinar, ainda que de forma preliminar, at? que ponto a microbiota associada a formigas dominantes e abundantes no dossel florestal poderia atuar na inibi??o de grupos microbianos invasivos e potencialmente entomopat?genos. Para tal, foi verificada a influ?ncia das intera??es entre a formiga Azteca chartifex, plantas da esp?cie Byrsonima sericea e bact?rias Gram-positivas e Gram-negativas dos corpos das oper?rias e da superf?cie das folhas. Um ensaio do efeito inibit?rio das pr?prias bact?rias e dos compostos extra?dos de A. chartifex sobre Xanthomonas citri subsp. Citri (XAC 306), Staphyloccocus aureus e S. epidermidis foi realizado. Em acr?scimo, foi verificado o efeito inibit?rio direto de bact?rias mutual?sticas associadas ao exoesqueleto das formigas contra bact?rias das superf?cies foliares de B. sericea. Finalmente, foi avaliado se as bact?rias mutual?sticas com as formigas e com maior potencial inibit?rio seriam Gram-negativas, devido ?s vantagens adaptativas das duas membranas deste tipo de bact?ria para ocupa??o de ambientes extremos. Verificamos que os compostos extra?dos de A. chartifex n?o tiveram efeito inibit?rio contra S. aureus e X. citri subsp. Citri. Ao contr?rio, os tratamentos contendo o extrato das formigas obtiveram maiores taxas de crescimento destas bact?rias. Por outro lado, foi encontrado que bact?rias associadas ? A. chartifex tiveram maior taxa de crescimento sobre bact?rias Gram-positivas associadas ?s folhas de B. sericeae que n?o possuem intera??o com essas formigas, portanto sugerindo potencial de inibi??o. Tamb?m foi detectado que a maior taxa de crescimento foi de bact?rias de formigas provenientes do ninho matriz em rela??o aos ninhos sat?lites. Os filos mais representativos dos isolados das formigas foram Proteobacteria, Firmicutes e Actinobacteria. Houve maior porcentagem de Gram-negativas nos tr?s grupos de amostras. Portanto, as formigas carregam bact?rias capazes de inibir microrganismos ex?genos ? microbiota associada ? A. chartifex, bact?rias Gram-negativas seriam mais competitivas que Gram-positivas, e h? um maior investimento em defesa dentro de col?nias onde h? maior densidade de indiv?duos, que seleciona isolados mais agressivas na inibi??o de bact?rias ex?genas ao sistema

    NASA space station automation: AI-based technology review. Executive summary

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    Research and Development projects in automation technology for the Space Station are described. Artificial Intelligence (AI) based technologies are planned to enhance crew safety through reduced need for EVA, increase crew productivity through the reduction of routine operations, increase space station autonomy, and augment space station capability through the use of teleoperation and robotics
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