bluuebunny/crossref_metadata_2025 huggingface dataset:
Efeito de luz e imersão em água na germinação de sementes de perpétua produzidas no Estado de São Paulo.
Authors: Sena Filho Antonio , Manoel Ferreira Bento , Julio Flórez-Roncancio Victor , Esmeralda Soares Payão Demattê Maria
Published: March 2015

Realizaram-se dois experimentos com sementes de perpétua (Gomphrena globosa L.) produzidas em Jaboticabal (SP). No primeiro, em temperaturas alternadas de 20-30oC, comparou-se apenas o efeito de 16 horas de luz por dia ou de escuro contínuo, para sementes das variedades de inflorescências brancas e purpúreas, logo após sua coleta. Para as duas variedades, verificou-se maior porcentagem de germinação com luz. Nos testes efetuados sem tratamento pré-germinativo e com luz, as médias das porcentagens de germinação variaram entre 64,5 e 81,0%. Desenvolveu-se o segundo experimento com sementes da variedade de inflorescências brancas, armazenadas durante seis mese em câmara seca. Em temperaturas alternadas de 20-30oC, a germinação foi mais lenta em escuro contínuo do que em 16 horas de luz por dia; a imersão prévia das sementes em água durante 24 horas foi prejudicial tanto à porcentagem como à velocidade de germinação.
Murcha bacteriana em oxális causada por Ralstonia solanacearum.
Authors: M.G. Almeida Irene , A. Malavolta Jr Valdemar
Published: March 2015

Observaram-se mudas de oxális apresentando sintomas de seca e queda de folhas, além de murcha e morte de plantas, ocorrendo em reboleiras, em canteiros de jardins da cidade de São Paulo (SP), além de descoloração no sistema vascular dessas plantas, com abundante exsudação bacteriana visualizada em exames microscópicos. Os isolamentos efetuados mostraram predominância de colônias bacterianas fluidas, de coloração branca com centro rosa em meio com tetrazólio, as quais foram caracterizadas como Ralstonia solanacearum (sin. Pseudomonas solanacearum), biovar 1, com base em testes bioquímicos e fisiológicos. Este é o primeiro relato da ocorrência dessa bactéria em oxális no Brasil. Linhagem bacteriana encontra-se depositada na Coleção de Culturas IBSBF sob no 1548.
Regeneração de plantas a partir de calos em gladíolo.
Authors: Cristiane Simões Fernanda , Duarte de Oliveira Paiva Patrícia , Pasqual Moacir , José Oliveira Néri Guilherme , Paiva Renato
Published: March 2015

Para a proliferação in vitro de calos de gladíolo (Gladiolus x grandiflorus L.), utilizaram-se gemas como explantes adicionadas em meio MS com 0,5 mg/L de 6-benzilaminopurina (BAP) e 1,0 mg/L de ácido naftalenoacético (ANA). Para a regeneração dos calos, testaram-se as concentrações de BAP (0; 0,5; 1,0; 2,0 e 4,0 mg/L) em combinação com ANA (0; 0,1 e 1,0 mg/L), em todas as combinações possíveis formando um esquema fatorial 5 x 3. A regeneração dos calos formados foi melhor na concentração 0,1 mg/L de ANA e na ausência de BAP, produzindo, em média, 2,07 brotos com tamanho médio de 2,27 cm. O objetivo do trabalho foi encontrar uma concentração ideal de reguladores de crescimento para a regeneração de plantas a partir de calos de gladíolo.
“Invented Invaders”
Authors: Lampert Evan
Published: March 2015

Invasive species, defined as exotic species that reach pest status, are major threats to global biodiversity. Although invasive species can belong to any taxonomic group, general characteristics such as rapid growth and reproduction are shared by many invasive species. “Invented Invaders” is a collaborative activity in which students invent and draw the “perfect” invasive species, made up of a combination of characteristics of actual invasive species in their geographic region. Students then list sustainable ways to control or manage the invented invader. This activity engages students and educates them about a continuing global problem while encouraging creativity and advocacy for the environment.
A Model Inquiry-Based Genetics Experiment for Introductory Biology Students
Authors: Setty Sumana , Kosinski-Collins Melissa S.
Published: March 2015

It has been noted that undergraduate project-based laboratories lead to increased interest in scientific research and student understanding of biological concepts. We created a novel, inquiry-based, multiweek genetics research project studying Ptpmeg, for the Introductory Biology Laboratory course at Brandeis University. Ptpmeg is a protein involved in axon formation in Drosophila melanogaster. In order to better understand Ptpmeg’s functionality, students sought to find Ptpmeg’s enhancers and suppressors by engaging in either a 4- or a 7-week modular research project. By the end of the semester, students were able to learn various laboratory techniques and acquire a deeper understanding of Drosophila genetics in both versions of the course.
Building a Twig Phylogeny
Authors: Flinn Kathryn M.
Published: March 2015

In this classroom activity, students build a phylogeny for woody plant species based on the morphology of their twigs. Using any available twigs, students can practice the process of cladistics to test evolutionary hypotheses for real organisms. They identify homologous characters, determine polarity through outgroup comparison, and construct a parsimonious tree based on synapomorphies (shared derived characters). This activity efficiently demonstrates many systematics concepts, including homology, homoplasy (convergence and reversal), polarity, synapomorphy, symplesiomorphy, autapomorphy, polytomy, and parsimony. It also engages students in inquiry, promotes student collaboration, raises awareness of plant structure, and exposes students to the diversity of common local trees.
Special Speciation
Authors: Countryman Lyn L. , Maroo Jill D.
Published: March 2015

Considerable anecdotal evidence indicates that some of the most difficult concepts that both high school and undergraduate elementary-education students struggle with are those surrounding evolutionary principles, especially speciation. It’s no wonder that entry-level biology students are confused, when biologists have multiple definitions of “species.” We developed this speciation activity to provide clarity and allow students a hands-on experience with a speciation model.
Vestigial Biological Structures
Authors: Senter Phil , Ambrocio Zenis , Andrade Julia B. , Foust Katanya K. , Gaston Jasmine E. , Lewis Ryshonda P. , Liniewski Rachel M. , Ragin Bobby A. , Robinson Khanna L. , Stanley Shane G.
Published: March 2015

Lists of vestigial biological structures in biology textbooks are so short that some young-Earth creationist authors claim that scientists have lost confidence in the existence of vestigial structures and can no longer identify any verifiable ones. We tested these hypotheses with a method that is easily adapted to biology classes. We used online search engines to find examples of 21st-century articles in primary scientific literature in which biological structures are identified as vestigial. Our results falsify these creationist hypotheses and show that scientists currently identify many structures as vestigial in animals, plants, and single-celled organisms. Examples include not only organs but also cells, organelles, and parts of molecules. Having students repeat this study will give them experience with hypothesis testing, introduce them to primary scientific articles, and further their education on vestigial structures.
Optimal Foraging by Birds
Authors: Pecor Keith W. , Lake Ellen C. , Wund Matthew A.
Published: March 2015

Optimal foraging theory attempts to explain the foraging patterns observed in animals, including their choice of particular food items and foraging locations. We describe three experiments designed to test hypotheses about food choice and foraging habitat preference using bird feeders. These experiments can be used alone or in combination and can also provide a foundation for students to develop extensions incorporating the basic methodology. We see these experiments as most applicable in secondary and postsecondary education, but they could be adapted for a variety of educational environments and for students with a variety of backgrounds.
Investigating Tree Thinking & Ancestry with Cladograms
Authors: Davenport KD , Milks Kirstin Jane , Tassell Rebecca Van
Published: March 2015

Interpreting cladograms is a key skill for biological literacy. In this lesson, students interpret cladograms based on familial relationships and language relationships to build their understanding of tree thinking and to construct a definition of “common ancestor.” These skills can then be applied to a true biological cladogram.
Factores que impactan los resultados empresariales: un estudio comparativo entre empresas chilenas y españolas
Authors: Huerta Patricia , Almodóvar Paloma , Pedraja Liliana , Navas José , Contreras Sergio
Published: March 2015

Los resultados empresariales representan un tema que sigue concentrando el interés de los investigadores y que aún no está resuelto. Es por ello que el presente estudio persigue dos objetivos: en primer lugar, realizar una revisión bibliográfica de los factores que impactan sobre los resultados empresariales; en segundo lugar, contrastar los planteamientos anteriores para aportar evidencia empírica al respecto, a través de un análisis comparativo entre dos países. Metodológicamente se realiza un contraste sobre paneles completos de empresas industriales chilenas y españolas, utilizando dos bases de datos: (i) la Encuesta Nacional Industrial Anual (ENIA) y (ii) la base de datos de la Encuesta sobre Estrategias Empresariales (ESEE), respectivamente, para el periodo 2000-2007. Utilizando análisis de componentes de varianza se identifican los factores que explican más del 90% de los resultados empresariales y, empleando técnicas para datos de panel, se descubre que estos factores también influyen en los resultados obtenidos. De este modo, el presente artículo avanza en la discusión del tema, a través de su aplicación a empresas de un país en vías de desarrollo como Chile, además de analizar un aspecto descuidado en la literatura como es el estudio de la influencia de los factores, sin concentrarse únicamente en el análisis del porcentaje de explicación de los factores identificados sobre los resultados empresariales; de igual manera, este trabajo actualiza el periodo tradicionalmente investigado e incorpora un factor relevante pero menos analizado en este tipo de estudios, como es la localización geográfica, factor que contribuye a explicar significativamente el modelo propuesto. Dentro de las repercusiones que implican el estudio, es evidente que sus resultados permitirán a los directivos y dueños de empresas comprender los elementos que influyen en los resultados organizacionales, los cuales son la base de su existencia y supervivencia en el futuro.
El empleo de la Webmetría para el análisis de los indicadores de desempeño y posición financiera de la empresa: un análisis exploratorio en diversos sectores económicos de los Estados Unidos
Authors: Romero-Frías Esteban , Vaughan Limen , Rodríguez Ariza Lázaro
Published: March 2015

El desarrollo de Internet a lo largo de las dos últimas décadas ha dado lugar a una nueva disciplina que permite estudiar la Web desde un punto de vista cuantitativo: la webmetría. La aplicación de técnicas webmétricas al estudio de empresas apunta a la posible existencia de relaciones entre el número de enlaces que recibe un sitio web corporativo y determinadas variables económico-financieras. La incipiente evidencia encontrada se limita, en todo caso, a empresas pertenecientes a sectores tecnológicos que, por su propia naturaleza, cuentan con una fuerte presencia en la Red. El presente trabajo, de carácter exploratorio, extiende el análisis a diversos sectores económicos de los Estados Unidos, confirmando la existencia de una relación significativa entre las variables expuestas. Esto abre nuevas posibilidades de investigación en el ámbito empresarial a partir del empleo de la información extraída de la estructura de enlaces de la Web.
UM ESTUDO COMPARATIVO ENTRE BANCO DE DADOS ORIENTADO A OBJETOS, BANCO DE DADOS RELACIONAIS E FRAMEWORK PARA MAPEAMENTO OBJETO/RELACIONAL, NO CONTEXTO DE UMA APLICAÇÃO WEB
Authors: Oliveira Manoel Marisergio Alves de , Carlos Danilo Gomes , Sousa Antonio Raimar do Vale Oliveira e , Castro Angelica Feliz de
Published: March 2015

Os bancos de dados relacionais são fortemente utilizados em sua forma direta, ou seja, a aplicação interagindo diretamente com o driver do SGBD, pois os mesmos há muito tempo vêm comprovando aspectos importantes, como confiabilidade e integridade dos dados, porém alguns frameworks oferecem, além disso, outras vantagens, sendo a mais importante a portabilidade entre os SGBDS. Por outro lado, os bancos de dados orientados a objetos oferecem maior agilidade e facilidade na modelagem dos dados. Neste artigo será apresentado um estudo de caso entre o uso de banco de dados relacionais puros, banco de dados relacionais com frameworks e banco de dados orientado a objeto.
CONTROLE ALTERNATIVO DE NEMATOIDE DAS GALHAS (Meloidogyne enterolobii) COM CRAVO DE DEFUNTO (Tagetes patula L.), EM SOLO
Authors: Carvalho Moreira Francisco José , Ferreira Antonio Carlos dos Santos
Published: March 2015

A correta identificação de fitopatógenos é de grande importância para se formar um acervo de dados que serão úteis para diagnose e controle. Com o aumento do plantio de goiaba no Ceará, percebe-se a presença de Meloidogyne associado à cultura e causando grandes prejuízos, contudo, o controle para tal moléstia ainda não existe. Em função disso, objetivou-se nesse ensaio avaliar o controle alternativo de M. enterolobii com a incorporação de fitomassa de cravo de defunto. O trabalho foi realizado de janeiro a maio de 2009, em Barbalha-CE. A avaliação do efeito da incorporação da fitomassa de cravo de defunto ao solo foi realizada em função da idade de transplantio (12, 18, 24 e 30 dias). Avaliou-se aos 35 dias após o transplantio do tomate, sendo mensuradas: número de galhas, peso fresco da parte aérea e do sistema radicular. Verificou-se que a incorporação da fitomassa de cravo de defunto ao solo apresentou-se eficiente na redução da população do nematoide. Conclui-se que a incorporação de fitomassa é eficiente na redução populacional de M. enterolobii e que 30 dias após o transplantio é a melhor época para se cortar e incorporá-la ao solo.
A SUSTENTABILIDADE NO ENSINO TÉCNICO EM ADMINISTRAÇÃO: CURRÍCULO OFICIAL OU OCULTO
Authors: Zamberlan João Fernando , Bortolotto Rafael Pivotto , Ramos Juliano Perlin de , Cabral Helenésio , Jesus Geofredy Montilla de , Leão Débora Ortiz de , Frizzo Kamila
Published: March 2015

A preocupação em aliar desenvolvimento econômico e social com a preservação dos recursos naturais é objeto de pesquisas nas mais diversas áreas do conhecimento, dentro do que rege o tema sustentabilidade. Torna-se imperativo que as instituições insiram estes temas em seus currículos. Sobre esta perspectiva, objetivo do nosso trabalho foi verificar qual a importância dada e se está presente a temática da sustentabilidade no currículo do curso Técnico em Administração. Para a pesquisa, foram entrevistados o coordenador do curso e os docentes que ministram as disciplinas técnicas do Colégio Politécnico da Universidade Federal de Santa Maria. A escolha dos docentes de acordo com as competências técnicas que ministram no curso Técnico em Administração. Os resultados mostraram que a sustentabilidade é importante para o curso e possui aplicabilidade na área sendo tratada por muitos docentes de forma transversal. Concluiu-se que a sustentabilidade encontra-se no currículo oculto por ser abordada no curso de forma implícita em outros conteúdos devido à iniciativa própria dos docentes, não constando no currículo oficial da escola.
EVALUATION OF VEGETABLE EXTRACTS FROM THE SEMI-ARID AS NATURAL pH INDICATOR
Authors: Torres Brilhante Sebastiana Estefana , Da Silva Paiva Valdevino Francisca Ítala , De Oliveira Neto Francisco Barros , Maia da Silva Francisco Felipe , Bertini Luciana Medeiros , Alves Leonardo Alcântara
Published: March 2015

Given the various difficulties to expose the contents of the subject of chemistry is a constant search for alternative materials to facilitate learning. This may partly be due to chemical science to be a significant practical character. However, due to professional educational institutions and material limitations ends up being passed on to the student of predominantly theoretical way, requiring a high degree of abstraction and consequently in their disinterest the same. In this context , we investigated the use of ethanol extracts of various plants, such as: Jitirana (Ipomoea glabra ), Íxora (Ixora coccínea), Centro (Centrosema brasilianum) and Candlebush (Senna alata) flowers, Beet (Beta vulgaris L.) fruit and Urucum (Bixa orellana) seeds as an acids and bases natural indicator, from laboratory tests capable of identifying properties demonstrate the pH. Initially we evaluated the variation in the coloration of extracts using for this buffer solutions at pH 3, 7 and 12. Among the cited vegetable flowers Jitirana, ixora and Centro presented activities relevant indicator as staining variants between pH 2:13. The extracts of plants were further added in glass tubes containing buffer solutions with a pH ranging from 2 to 13. The change in color of the extracts showed good activity has the same pH indicator.
A INTERNALIZAÇÃO DOS PRINCÍPIOS DA NORMA ISO 26000: O CASO DA PETROBRAS
Authors: Silva Arthur William Pereira da , Siqueira Elisabete Stradiotto
Published: March 2015

A ISO (International Organization for Standardization) 26000 vem contribuindo com o desenvolvimento da responsabilidade social empresarial, porém ainda mantém a natureza genérica, característica das abordagens anteriores e a ausência de indicadores. Dentro desse contexto, questiona-se se a ausência de indicadores da norma ISO 26000 compromete a avaliação e consequentemente a internalização do comportamento socialmente responsável por parte das organizações? Para responder a tal questionamento é proposto neste artigo analisar o relatório de sustentabilidade da PETROBRAS (Petróleo Brasileiro S/A) a fim de identificar de que forma os princípios da norma ISO 26000 são internalizados. O método utilizado foi o estudo de caso, sendo a empresa objeto do estudo a PETROBRAS. A técnica escolhida para a coleta dos dados foi a pesquisa documental. Os resultados e as discussões evidenciaram que existem incoerências entre os discursos sobre responsabilidade social da PETROBRAS e parte de suas ações e que a existência dessas divergências entre discurso e práticas torna-se possível graças à generalidade da norma, como também, pela ausência de indicadores.
A DANÇA DO REI: O BALÉ DE CORTE E O PODER DE SOBERANIA EM FOUCAULT
Authors: Fantini Wilne de Souza
Published: March 2015

No presente artigo teceremos algumas análises acerca do funcionamento do poder de soberania em Foucault e as relações desse poder com o corpo do indivíduo e com o surgimento, no domínio da dança, do balé de corte. O poder de soberania é um poder de obediência por vincular soberano e súdito. Segundo Foucault, esse poder funciona através de rituais e cerimônias (gestos, hábitos, sinais de respeito, brasões etc.) que se inserem no nível mais elementar do corpo social, pois ele se refere a uma série de poderes microscópicos que penetram nos comportamentos cotidianos e nos corpos dos indivíduos. A efetivação do poder de soberania na área da dança aparece no balé de corte que nasceu na França do século XVI. Esse balé era amiúde uma combinação de arte, de política e de entretenimento. Além do papel de passatempo para o monarca e sua comitiva, o balé de corte também tinha a função de ratificar o poder soberano. Ao dançar nos balés, o rei fazia lembrar seu poder de controle da cena social, econômica e política. Consequentemente, havia um domínio do monarca sobre os corpos dos indivíduos de tal modo que quando um indivíduo transgredia uma lei, ele atingia o próprio soberano porque a lei era expressão de sua vontade. Até o século XVIII os corpos dos indivíduos eram a única riqueza acessível que legitimava o poder absoluto do soberano e, portanto, há uma relação do poder de soberania e do suplício como punição. As cerimônias dos suplícios eram um ritual cuja função jurídico-política era de reconstituir a soberania lesada por um instante.
“Was Taking Me Out of the Home Necessary?” Perspectives of Foster Youth on the Necessity for Removal
Authors: Jones Loring Paul
Published: March 2015

The public views on child protection are often negative and assume that children in care are uniformly unhappy and would rather be at home than in care. This qualitative research sought to give voice to youth on their foster care experience. Former foster youth were asked to recall being removed from their home and reflect on whether they thought removal was necessary. More than three quarters thought removal was necessary and beneficial; 16% disagreed with the removal decision. The reasons given by both sets of youth are discussed. These results support other research findings that suggest foster youth are more satisfied than dissatisfied with care. The implications of these findings for policy are discussed.
Pacific Islander Youth and Sources of Risk for Problem Behaviors (Research Note)
Authors: Davis Robin L. , Vakalahi Halaevalu F. O. , Smith Larry L.
Published: March 2015

This analysis focused on family, community, school, and individual/peer-based factors that can contribute to problem behaviors among Pacific Islander youth. This study included Native Hawaiian, Samoan, and Tongan youth which are the largest Pacific Islander groups in Utah (U.S. Census Bureau, 2000). The larger study consisted of 30,000 youth participants of which 530 were Pacific Islanders. Participating Pacific Islander youth reported higher levels of actual, as well as risk for, problem behaviors compared to other youth in the study. Pacific Islander youth also reported significantly lower levels of opportunities for prosocial involvement and rewards for involvement in the community but high levels of family attachment and religiosity. Implications for the future are provided.
Hemiparasitic plant impacts animal and plant communities across four trophic levels
Authors: Hartley S. E. , Green J. P. , Massey F. P. , Press M. C. P. , Stewart A. J. A. , John E. A.
Published: March 2015

Understanding the impact of species on community structure is a fundamental question in ecology. There is a growing body of evidence that suggests that both subdominant species and parasites can have disproportionately large effects on other organisms. Here we report those impacts for a species that is both subdominant and parasitic, the hemiparasite Rhinanthus minor. While the impact of parasitic angiosperms on their hosts and, to a lesser degree, coexisting plant species, has been well characterized, much less is known about their effects on higher trophic levels. We experimentally manipulated field densities of the hemiparasite Rhinanthus minor in a species‐rich grassland, comparing the plant and invertebrate communities in plots where it was removed, present at natural densities, or present at enhanced densities. Plots with natural and enhanced densities of R. minor had lower plant biomass than plots without the hemiparasite, but enhanced densities almost doubled the abundance of invertebrates within the plots across all trophic levels, with effects evident in herbivores, predators, and detritivores. The hemiparasite R. minor, despite being a subdominant and transient component within plant communities that it inhabits, has profound effects on four different trophic levels. These effects persist beyond the life of the hemiparasite, emphasizing its role as a keystone species in grassland communities.
Responses of a desert nematode community to changes in water availability
Authors: Vandegehuchte Martijn L. , Sylvain Zachary A. , Reichmann Lara G. , de Tomasel Cecilia Milano , Nielsen Uffe N. , Wall Diana H. , Sala Osvaldo E.
Published: March 2015

The most recent climate models unequivocally predict a strong drying trend for the southwestern USA within the next century. Soil nematodes are a highly important component of desert ecosystem functioning, but rely on water films for movement. However, it is currently poorly understood how different trophic groups of nematodes respond to chronic presses as well as short‐lived pulses of altered water availability, especially in arid systems where such changes are expected to have the greatest impact. The aim of this study was to assess the effects of both instantaneous and long‐term variation in water availability on desert soil nematode trophic groups. We hypothesized that nematode abundance would respond positively to both short‐ and long‐term increases in moisture. Based on the ecology of the different trophic groups we further made predictions about their relative rates of response. We increased or decreased precipitation from ambient levels in the Chihuahuan Desert for four consecutive years and sampled soil nematodes after two, three and four years. We tested the effects of altered precipitation treatments through time as well as gravimetric soil moisture at the time of sampling on the abundance of the different nematode trophic groups. In contrast to our hypotheses, the abundances of most nematode trophic groups were unaffected by the amount of precipitation, even after four years of altered precipitation. Plant‐parasitic nematodes from low moisture soils were the only group that reacted positively to increased precipitation from the third year onwards. Trophic groups responded differently to soil moisture, with bacterivores decreasing with increasing moisture and omnivores showing a positive relationship that diminished over time. We show that in general, these desert nematodes were not limited by precipitation, and were highly resilient to decreases therein. However, when also considering the effects of soil moisture, some more complex patterns and differences among trophic groups emerged. We discuss potential mechanisms explaining these observations and contrast our findings with those from other ecosystems around the world. We conclude that deserts harbor nematode communities that seem more resilient to altered water availability than other ecosystems.
Effects of elevation and land use on the biomass of trees, shrubs and herbs at Mount Kilimanjaro
Authors: Ensslin Andreas , Rutten Gemma , Pommer Ulf , Zimmermann Reiner , Hemp Andreas , Fischer Markus
Published: March 2015

The protection and sustainable management of forest carbon stocks, particularly in the tropics, is a key factor in the mitigation of global change effects. However, our knowledge of how land use and elevation affect carbon stocks in tropical ecosystems is very limited. We compared aboveground biomass of trees, shrubs and herbs for eleven natural and human‐influenced habitat types occurring over a wide elevation gradient (866–4550 m) at the world's highest solitary mountain, Mount Kilimanjaro. Thanks to the enormous elevation gradient, we covered important natural habitat types, e.g., savanna woodlands, montane rainforest and afro‐alpine vegetation, as well as important land‐use types such as maize fields, grasslands, traditional home gardens, coffee plantations and selectively logged forest. To assess tree and shrub biomass with pantropical allometric equations, we measured tree height, diameter at breast height and wood density and to assess herbaceous biomass, we sampled destructively. Among natural habitats, tree biomass was highest at intermediate elevation in the montane zone (340 Mg ha−1), shrub biomass declined linearly from 7 Mg ha−1 at 900 m to zero above 4000 m, and, inverse to tree biomass, herbaceous biomass was lower at mid‐elevations (1 Mg ha−1) than in savannas (900 m, 3 Mg ha−1) or alpine vegetation (above 4000 m, 6 Mg ha−1). While the various land‐use types dramatically decreased woody biomass at all elevations, though to various degrees, herbaceous biomass was typically increased. Our study highlights tropical montane forest biomass as important aboveground carbon stock and quantifies the extent of the strong aboveground biomass reductions by the major land‐use types, common to East Africa. Further, it shows that elevation and land use differently affect different vegetation strata, and thus the matrix for other organisms.
Proper Selection of Surfactants for Enhanced Oil Recovery Applications Based on Interfacial Rheology Measurements of Oil-Water Interfaces
Authors: Rane Jayant P. , Xu Liang
Published: March 2015

Asphaltenes are indigenous species in crude oil responsible for formation of tight crude oil-water emulsion during oil recovery. It is important to understand interfacial behavior of asphaltenes at the oil-water interface to understand the oil recovery process. In recent studies, using pendant drop as Langmuir trough and interfacial rheology measurements, it was concluded that asphaltenes follow a Langmuir equation of state (EOS). Such a Langmuir EOS involves only one parameter, namely surface excess coverage, which is actually the size of the molecule at the interface.

This study discusses creation of asphaltene stabilized interfaces from four crude oils from the Monterey shale and extracted asphaltene powder. Interfacial rheology and pendant drop measurements were conducted and it can be observed that the Langmuir EOS is followed for all four oils and extracted asphaltenes. The size of molecule at the interface is approximately 0.36 nm2 for all crude oils and 0.34 nm2 for extracted asphaltenes, respectively, which is consistent with the well-known Yen Mullins model. It confirms that crude oil-water interfaces are predominantly stabilized by asphaltene molecules present in crude oil.

Asphaltene stabilized interfaces are exposed to the weakly emulsifying (WE) and non-emulsifying (NE) surfactant families, which have been widely used during matrix acidizing operations in the Monterey shale. Interfacial rheology measurements conclude that asphaltene stabilized interfaces are elastic. Elastic interfaces are almost immobile (solid-like) and hence, during oil recovery, can cause issues while flowing through porous media. WE surfactants, as studied previously, form a weak emulsion during oil recovery, which aids more recovery 1–3. WE surfactants also reduce the elastic modulus of the interface significantly within seconds to make the interface mobile and deformable. Hence, it helps the oil droplet mobilize, squeeze, or elongate through the pores during oil recovery. NE surfactants, on the contrary, reduce elastic modulus slowly and do not appear to reduce the elastic modulus enough to make interface deformable (still remains elastic).

Corresponding field data shows that wells treated with WE surfactants show higher oil recovery consistently than those wells treated with NE surfactants.
An Analysis of Cyclic Steam Stimulation Projects in the California Opal A Diatomite
Authors: Elias Ramon , Powell Trey , Medizade Mason
Published: March 2015

Cyclic steam stimulation (CSS) in the California Opal A diatomite has been a successful commercial oil recovery technique since the 1990s. This paper analyzes the production performance of several California CSS diatomite projects comparing actual and calculated steam-oil ratios, SOR, as a function of oil recovery to ascertain whether a project is performing up to its full potential. SORs are computed using simplified Buckley-Leverett fractional flow theory applied to steam injection.

SOR, or its reciprocal oil-steam ratio (OSR), have always been useful qualitative indicators of CSS project performance; but have not been used to optimize production performance other than to say operators should strive to keep the SOR low, or the OSR high. We show that an SOR equal to about 1 is what a CSS diatomite project should achieve through the recovery of about 20% of the oil-in-place, or more, to yield the highest oil production for a given set of conditions. A corresponding “optimum” steam injection rate is discussed. Projects that are managed this way have the highest average oil production rate per well and the lowest instantaneous SOR.

This study shows that steam over-injection in the diatomite is common even when the injected cold water equivalent (CWE) steam is “in balance” with the oil and water that are produced. Although not discussed in detail, we postulate that the low permeability diatomite has an inherent low rate of heat absorption compared to other oil bearing rocks that can cause too much vapor to accumulate around the well when steam injection becomes excessive. Relative permeability effects develop during flow back that give way to (a) the preferential flow of steam to the producer and (b) constrained re-saturation of the heated zone.

Avoiding this tendency helps insure good project performance including high oil flow rates and high oil recovery. Although the calculation method we discuss is used for CSS in the low permeability diatomite, it should be helpful in all CSS applications. Improving CSS steam practices will have the added benefit of lowering the carbon intensity of the oil that is produced.

Our analysis uses published data for the needed input parameters including information from the California Division of Oil, Gas and Geothermal Resources (DOGGR) internet web data base.
Salmonid Acclimatisation in Colonial Victoria: Improvement, Restoration and Recreation 1858-1909
Authors: Minard Peter
Published: March 2015

Aquaculture and salmonid acclimatisation in Victoria drew upon and adapted European and American precedents to reflect local circumstances and priorities. Multiple attempts were made to acclimatise various species of European and American salmonids in Victoria throughout the nineteenth century. The Acclimatisation Society of Victoria assembled a salmonid acclimatisation network that combined transnational aquaculture expertise with local commercial imperatives, a desire to restore damaged fisheries and a unique local acclimatisation theory. This network was subsequently used and transformed by regional fish acclimatisation societies and private individuals. The network finally collapsed with the professionalisation of the Victorian fisheries in the 1880s and the establishment of the Fisheries and Game department in 1909. Exploring the rise and fall of this network demonstrates and analyses the operation of transnational acclimatisation knowledge and practices.
The Concept of Climate Improvement: Colonialism and Environment in German South West Africa
Authors: Siiskonen Harri Olavi
Published: March 2015

The desiccation theories formulated in the eighteenth century pointed out the connection between deforestation, rainfall reduction and climate change. After the 'Scramble for Africa' the conservation philosophy of the European colonial powers was based on anti-desiccation forest policy. This article seeks to consider how the concepts of 'desiccationism' were taken into account by the German colonists in forest and land management of their new colony: South West Africa. The conservation policy carried out by the German colonial administration was very controversial because they were interested only in areas suitable for European settlement. The early twentieth century idea of improving the climate of South West Africa by greening the Central Highland and the Namib Desert was an excellent indication of a firm belief in science. The other side of the coin was that no environmental responsibility was taken for the African reserves.
Les paradoxes des politiques multiculturelles en Bolivie : entre inclusion et exclusion
Authors: Canessa Andrew
Published: March 2015

La Bolivie est un bon exemple de pays ayant placé le multiculturalisme au centre de son idéologie politique. L’actuelle administration Morales ne se contente pas de cautionner les politiques multiculturelles, elle a également inscrit les principes d’une nation multiculturelle et pluriethnique dans la nouvelle Constitution. Cet article décrit certains paradoxes au cœur de cette nation multiculturelle : le nouveau discours sur l’indigénéité est utilisé autant pour affranchir les masses subalternes que pour exclure d’autres populations privées d’accès aux discours du pouvoir. L’auteur montre ici que lorsque l’indigénéité passe d’un langage de protestation au langage de la gouvernance, elle peut être un facteur d’affranchissement autant que d’exclusion.
Métis malgré tout : une résistance Amazonienne aux politiques ethniques
Authors: Véran Jean-François
Published: March 2015

Nação Mestiça est un mouvement politique né des banlieues pauvres de Manaus, capitale de l’État d’Amazonie, en réaction aux politiques dites « ethno-raciales » qui se développent à l’échelle nationale depuis le début des années 2000. Dans l’objectif de restituer et comprendre le point de vue logique à partir duquel ses militants questionnent la démocratie brésilienne, l’article montre dans un premier temps comment Nação Mestiça défend le métissage dans le parfait contresens de la déconstruction idéologique par laquelle le concept s’est vu progressivement destitué de toute légitimité au plan politique national. Il sera ensuite argumenté que cette posture doit être comprise à partir d’une pragmatique de l’expérience métisse, dans laquelle s’inscrit une conception particulière des rapports entre métissage et démocratie. Il s’agira finalement de montrer comment le mouvement déplace le débat sur les politiques « affirmatives » en le re-territorialisant au sein de l’espace pratique des enjeux micro-locaux.
Chronique d’une ethnogenèse annoncée – Histoire des luttes indiennes contemporaines dans le Nord-ouest argentin (1970-2014)
Authors: Boullosa-Joly Maïté
Published: March 2015

On assiste à un processus important d’ethnogenèse dans la région du Nord-Ouest argentin. Il est lié au développement des lois multiculturelles qui donnent des droits culturels, sociaux et territoriaux aux populations autochtones depuis la fin des années 1980. Afin de comprendre ce processus d’ethnicisation, nous reviendrons sur l’histoire coloniale de la région et sur le traitement subi par les Indiens qu’on a dépossédés de leur territoire. Cette dépossession s’est accentuée après l’indépendance au 19 e siècle dans un pays qui, ayant construit son identité nationale sans les prendre en compte, a été considérée comme une Nation sans indiens. Comment expliquer alors ce renouveau identitaire que connaît aujourd’hui l’Argentine ? Nous reviendrons sur 40 ans d’histoire de luttes sociales et territoriales menées par les populations dans le Nord-Ouest argentin qui se revendiquent Diaguita Calchaquies. Mais nous verrons aussi les stratégies employées par les propriétaires terriens pour délégitimer les arguments des organisations indianistes. Les situations sont cependant très contrastées, plus ou moins violentes selon les contextes. Ces études de cas nous permettront de mesurer les avancées qu’a permis l’implantation des lois multiculturelles dans le pays, la valorisation identitaire qu’elles ont suscitée, les droits qu’elles ont permis de réclamer, mais d’en observer aussi les ambiguïtés et les limites.
Le double discours des politiques d’éducation interculturelle bilingue au Paraguay
Authors: Boidin Capucine
Published: March 2015

La nouvelle Constitution du Paraguay en 1992 a reconnu le guarani comme langue officielle sur tout le territoire national aux côtés de l’espagnol. Depuis 1994 une politique nationale d’éducation bilingue interculturelle a été lancée. Le Paraguay est proclamé comme étant un pays “bilingue et pluriculturel”. Mais ce ne sont pas tant des politiques multiculturelles qui sont mises en place qu’une nouvelle manifestation de nationalisme paraguayen : la communauté nationale est imaginée comme métisse et bilingue guarani espagnol, à l’exclusion de toute autre identité ethnique. Pour comprendre la spécificité de ces politiques, il faut les situer en continuité avec la gestion historique des altérités au Paraguay à l’époque coloniale et indépendantiste : une altérité incorporée (guarani) et des altérités maintenues en état d’extériorité (Ayoreo, Aché, Enxet, Mbya...). Cela étant dit, si au niveau politique le guarani bénéficie d’une forte reconnaissance symbolique, au niveau de la planification linguistique, de nombreuses résistances envers l’usage officiel du guarani peuvent être observées. Parallèlement à cette officialisation et visibilisation croissante, se multiplient les propositions pour effacer les connotations indigènes de la langue au profit de ses dimensions nationales.
L’Afrique : futur eldorado des médias francophones ?
Authors: d’Amours Liette , Lafrance Sylvain
Published: March 2015

Selon les prévisions de l’Organisation internationale de la francophonie (OIF), la planète devrait compter quelque 770 millions de francophones d’ici 2050, alors qu’elle n’en dénombre aujourd’hui que 200 millions. Fait encore plus étonnant : neuf locuteurs français sur dix habiteraient alors l’Afrique. À ce compte, pas surprenant que les plus grandes puissances du monde multiplient actuellement les actions pour explorer, voire exploiter, tout le potentiel économique de ce nouvel Eldorado. À l’heure où l’industrie des médias est en pleine redéfinition, n’est-ce pas l’occasion d’amorcer une réflexion majeure sur ces futurs marchés ?
La gouvernance de la gestion des risques : quoi de neuf ?
Authors: Moreau Rémi , Dionne Georges
Published: March 2015

La gestion des risques des entreprises a grandement évolué depuis 25 ans. De nos jours, elle englobe plusieurs aspects dont la prévention, la précaution, la gestion financière et l’utilisation de l’assurance. Cela dit, quels sont les effets d’une bonne gouvernance sur la valeur d’une entreprise et qu’en est-il de la compétence des membres des conseils d’administration ?
Yves Pigneur et le Business Model Generation : un modèle d’affaires au service d’un livre... ou vice versa ?
Authors: Cardinal Jacqueline
Published: March 2015

Un million d’exemplaires vendus, traduit en 30 langues, distribué partout au monde, le livre Business Model Generation a connu une gestation hors norme. Qu’on en juge : deux coauteurs, 470 contributeurs payants recrutés dans 45 pays par l’intermédiaire du Net, un noyau dur de concepteurs, designers, vidéastes et éditeurs, travaillant de concert en ligne à l’élaboration d’un projet exaltant ! Voilà de quoi interpeller tant les entrepreneurs de PME et les dirigeants de grandes entreprises que les gestionnaires désireux de transformer leurs idées porteuses en entreprises performantes et innovantes.
Modèles d’affaires à surveiller
Authors: d’Amours Liette
Published: March 2015

Quels sont les modèles d’affaires en émergence ? Lesquels suscitent actuellement suffisamment l’intérêt des chercheurs universitaires pour être étudiés et cités en exemple ? Quels sont leur potentiel et leurs limites ? Pleins feux sur des modèles d’affaires à surveiller de près au cours des prochaines années et qui font grandement place à l’innovation et à la créativité, tels que Sensorica, Airbnb, Uber, etc.
Système de santé : l’ère du guichet automatique
Authors: Auger Claudine
Published: March 2015

Désengorger le réseau de santé québécois, à un moment où la croissance des coûts, la population vieillissante et l’accessibilité aux soins semblent, à eux seuls, le mener tout droit vers le chaos ? Possible, pourtant, selon certains fervents de la télésanté. En fait, sans évincer toutes les difficultés auxquelles fait face le réseau de la santé, les technologies de l’information offrent de grandes possibilités en défiant l’espace-temps : la distance n’est désormais plus un obstacle, transformant avantageusement les pratiques et l’organisation des services ; le temps est décuplé et les compétences des spécialistes, à portée de caméra.
Communiquer la marque employeur sur les médias sociaux
Authors: Lessard Steven
Published: March 2015

Dans un contexte de rareté et de pénurie de main-d’œuvre, les médias sociaux représentent d’importants canaux de communication dans la diffusion de la marque employeur. En plus de rejoindre de nombreux publics et d’interagir avec eux, les médias sociaux permettent d’intéresser et de mettre à l’avant-plan les employés, ce qui permet, au final, d’humaniser l’entreprise. Néanmoins, une organisation doit s’assurer de prévoir des ressources financières suffisantes ainsi que de consacrer le temps et les efforts nécessaires dans la gestion de sa présence en ligne. Tout en encadrant et en formant les employés pour qu’ils deviennent de bons ambassadeurs de la marque, l’entreprise doit également veiller à prévenir les débordements en mettant en place une gestion de crise.
Expert Modeling, Expert/Self-Modeling Versus Lecture: A Comparison of Learning, Retention, and Transfer of Rescue Skills in Health Professions Students
Authors: Kardong-Edgren Suzan , Butt Ann , Macy Rosemary , Harding Sarah , Roberts Caleb J. , McPherson Sterling , Waddell Alexandra , Erickson Amanda
Published: March 2015

Background:

It is unclear whether traditional lecture followed by simulation leads to the best learning and knowledge and skill retention over time.

Method:

A 3×4 mixed design study used three modes of education—traditional lecture with self-guided learning, expert modeling/dual viewing with brief questioning, and expert plus self-modeling—at four time points to compare knowledge, time to treat, and correct steps over time.

Results:

No significant differences were found in knowledge or time to treat between training methods. An expert modeling/ dual viewing group with brief questioning performed more steps correctly (
p
= 0.05) than did the other two groups.

Conclusion:

Expert modeling may help students remember and perform a complex series of tasks in a scenario. Further research is needed to explore expert modeling for novice learners. [
J Nurs Educ.
2015;54(4):185–191.]
A Correlation Study of Social Network Usage Among Health Care Students
Authors: Suit Louise , Winkler Patricia , Campbell Linda , Pennington Karen , Szutenbach Mary Pat , Haight Robert , Roybal Deborah , McCollum Marianne
Published: March 2015

Background:

Due to anecdotal concerns about adequacy of health professions students’ communication skills, health professions faculty at a private university formed an interprofessional research team. The study was designed to explore whether the use of social networking services (SNS) influenced health care students’ written and oral communication skills.

Method:

One hundred thirty-two students participated in the study. Communication skills were assessed by using assignments from a health care ethics course required of all students. Use of SNS was measured with an information technology questionnaire.

Results:

Contrary to expected findings, this exploratory correlation study found no meaningful relationship between the frequency of SNS usage and oral and written communication skills in health professions students.

Conclusions:

Future studies of SNS would benefit from a younger and more homogeneous study population to assess the use of SNS for learning versus leisure. [
J Nurs Educ.
2015;54(4):207–213.]
Impact of the Ice Cover onto Seismic Waves' Propagation in Shallow Arctic Water
Authors: Tcheverda V.A. , Khaidukov V.G. , Lisitsa V.V. , Reshetova G.V.
Published: March 2015

Seismic study of transition zones in Arctic regions in summer is troublesome because of the presence of large areas covered by shallow waters like bays, lakes, rivers, their estuaries and so on. The winter is more convenient and essentially facilitates logistic operations and implementation of seismic acquisition. But in winter there is a complicating factor - intensive seismic noise generated for acquisitions installed on the ice covering shallow waters. It is well-known that this noise is connected with flexural waves generated in ice by seismic sources. These waves are one of the strongest known coherent noises. At the same time they are much slower than surface waves well known for onshore acquisition and seem to be easy avoided by f-k filtration. However, this type of filtration fails to suppress such noise. To understand the matter the representative series of numerical experiments are conducted and prove that the main impact to noise is multiple conversions of flexural waves to the body ones and vice versa. Ways to reduce this noise are proposed and discussed.