bluuebunny/crossref_metadata_2025 huggingface dataset:
SURGICAL MANAGEMENT OF CYSTIC LESIONS OF THE PANCREAS: A SINGLE-CENTRE EXPERIENCE
Authors: SIA Gabriela Beatriz , SOARES Pedro França da Costa , GESTIC Martinho Antonio , CHAIM Elinton Adami , CALLEJAS-NETO Francisco , CAZZO Everton
Published: February 2019

ABSTRACT BACKGROUND: Cystic lesions of the pancreas represent a group of pancreatic diseases with great histological heterogeneity, varying from benign lesions, some of them with malignant potential, to overt malignant lesions. OBJECTIVE: To describe the cases of cystic lesions of the pancreas which underwent surgical intervention at a tertiary university hospital. METHODS: This is a retrospective population-based study (historical cohort) which was carried out enrolling individuals attended at the Outpatient service of Pancreas Surgery of the Hospital de Clínicas of Unicamp. The individuals underwent surgical procedures performed from January 2012 through December 2016. RESULTS: In the period evaluated, 39 cases of cystic lesions of the pancreas which underwent surgery were identified, 26 (66.6%) of which were female. The average age at diagnosis was 47.4±16.4 years (range, 18-73). In regards to symptoms, 35 (89.7%) were symptomatic. The average length of hospital stay was 10 days (range 4-76). Surgeries performed to treat the lesions depended on the localization and type of the lesions: cystojejunostomy (41%), distal pancreatectomy (36%), pancreaticoduodenectomy (15.4%), drainage of ruptured and/or infected pseudocyst (5.2%) and central pancreatectomy (2.6%). CONCLUSION: Cystic lesions of the pancreas are a group of lesions with a highly varying presentation and diagnostic approach and may require an also highly variable surgical treatment. An appropriate preoperative imaging diagnosis is essential for their management.
CONGENITAL HEPATIC FIBROSIS AND OBLITERATIVE PORTAL VENOPATHY WITHOUT PORTAL HYPERTENSION - A REVIEW OF LITERATURE BASED ON AN ASYMPTOMATIC CASE
Authors: GUERRA Juliana Arrais , KAMPA Kátia Cristina , ZAPPAROLI Maurício , ALVES Venâncio AF , IVANTES Cláudia Alexandra Pontes
Published: February 2019

ABSTRACT The disease and the case reported here are relevant especially because of their varied clinical presentation, possibility of being associated with other disorders affecting several organs and possible differential diagnoses. Congenital Hepatic Fibrosis is an autosomal recessive disease due to mutation in the PKHD1 gene, which encodes the fibrocystin/polyductine protein. It is a cholangiopathy, characterized by varying degrees of periportal fibrosis and irregular proliferation of bile ducts. Affected patients are typically diagnosed in childhood, but in some cases the disease may remain asymptomatic for many years. The exact prevalence and incidence of the disease are not known, but it is consider a rare disease, with a few hundred cases described worldwide. It can affect all ethnic groups and occur associated with various hereditary and non-hereditary disorders. The clinical presentation is quite variable, with melena and hematemesis being initial symptoms in 30%-70% of the cases. More rarely, they may present episodes of cholangitis. The disease has been classified into four types: portal hypertension, cholestasis / cholangitis, mixed and latent. Diagnosis begins with imaging tests, but the definition is made by the histopathological sample. So far, there is no specific therapy that can stop or reverse the pathological process. Currently, the therapeutic strategy is to treat the complications of the disease.
A educação como direito social e a escola como espaço protetivo de direitos: uma análise à luz da legislação educacional brasileira
Authors: Santos Émina
Published: February 2019

Resumo Problematiza-se neste artigo de revisão documental e bibliográfica, pertencente à área de estudos em Educação em Direitos Humanos (EDH), a qualidade social da educação escolar a partir da análise da sua institucionalidade no marco normativo educacional instituído após a Constituição Federal de 1988. Tais atos legislativos legalizam uma função inovadora para a escola, a de ser e atuar como espaço protetivo de direitos de crianças e adolescentes. No entanto, o que se constata é que o ambiente escolar ainda se constitui como lugar da escolarização baseada na lógica do trabalho e do ideal de abundância do consumo como sinônimo de felicidade. Propõe-se, a partir do exposto, que a escola protetiva atue a partir de uma dinâmica distributiva de saberes transformando a máxima liberal da igualdade de oportunidades e meritocracia em intervenção estatal pela educação equitativa, como justiça social. Para tal, a educação como direito humano fundamental, e a escola como espaço de proteção social devem assimilar características que vão além da simples socialização de conteúdos instrucionais, devendo abranger princípios como totalidade, disponibilidade, acessibilidade, aceitabilidade e adaptabilidade. Dessa forma, concebemos EDH como indispensável à formação de agentes capazes de potencializar a escola como espaço de proteção social. Referida formação deve ser, portanto, constitutiva da identidade profissional dos que atuam na escola e nas demais instituições componentes da rede de proteção social no sistema de garantia de direitos.
Critical state behaviour of an unsaturated high-plasticity clay
Authors: Burton Glen J. , Sheng Daichao , Airey David W.
Published: February 2019

This paper describes a series of tests carried out to examine triaxial compression and shearing of a high-plasticity compacted clay. Reconstituted and compacted samples which were saturated are used as a basis for interpreting the unsaturated test results within a critical state soil mechanics (CSSM) framework. The shear strength behaviour of unsaturated soils have previously been found to be reasonably well captured in a CSSM framework, whereas the volume change behaviour has been more difficult to rationalise. Based on test results presented using the Bishop effective stress, the volume change behaviour during shear suggests that a unique critical state line is approached, independent of the applied suction. The normalised shearing behaviour of the compacted unsaturated soil is interpreted to be analogous to that of saturated-structured soils.
Manufacturing wall panels using waste sawmill dust bonded by polystyrene waste
Authors: Mwasha Abrahams , Ramdhanie Dillon
Published: February 2019

Sawmill dust bonded with polystyrene waste as a binder is being considered for producing wall panels that will exhibit improved physical and mechanical properties. Test specimens were produced from various composites, which were used to perform flexural, tensile and water absorption tests. The samples were left to cure at room temperature for 12 and 28 d. The results obtained displayed that the composition of 60% sawdust 40% polystyrene slurry was the optimum composition, yielding the highest tensile strength of 8·355 N/mm2 and rupture modulus of 5·72 N/mm2, with desirable water absorption properties when compared with some of the manufactured wood samples (particle board and plywood).
Subsurface S-type Granitoid Identification Based on Gravity and Seismic Tomography Models in Pacitan, East Java
Authors: Soesilo Joko , Palupi Indriati Retno , Raharjo Wiji , Sutanto Sutanto , Sulistyohariyanto Faris Ahad , Ekaristi Kevin Gardo Bangkit , Stiawan Fandi Budi
Published: February 2019

ABSTRACT Granitoid outcrop has been observed in Montongan, Tulakan Subdistrict, Pacitan District, East Java. Geochemically, granitoid shows peralluminous S-type granitoid which consists of comparable plagioclase and potassium feldspar leading to adamelite and granodiorite variety with andalusite, fine size corundum and cordierite inside. These modal minerals are consistent with its bulk chemical analysis result that shows alumina rich rock. Highly weathered spotted pinkish soil with remaining quartz gravels characterizes its surface. Lateritic pink soil up to more than 25 meters thick covers the granitoid body and this feature is indicative to locate its surface distribution, while its subsurface distribution is remain uncertain. The research aimed to identify granitoid subsurface distribution. To identify the subsurface body, gravity and seismic tomography models were used. According gravity model, the pluton body is 5 km wide which is rootless downward and seems extends eastward. Meanwhile, the north-south seismic tomographic model across Pacitan Region indicates dense solid body override the recent Java subduction zone. The body is assumed to have correlation with surface granitic rock. It supports an idea that there is a micro continent trapped beneath Southern Mountain of East Java. ABSTRAK Singkapan granitoid telah teramati di daerah Montongan, Kecamatan Tulakan, Kabupaten Pacitan, Jawa Timur. Secara geokimia, granitoid Pacitan memperlihatkan granitoid peralumina tipe-S yang tersusun berdasarkan perbandingan plagioklas dan kalium felspar menunjuk pada varian adamelit dan granodiorit dengan andalusit, korundum halus dan kordierit di dalamnya. Mineral modal tersebut konsisten dengan hasil analisis kimia total yang menunjukkan batuan kaya alumina. Tanah berwarna merah muda yang sangat lapuk dengan kerikil sisa kuarsa menjadi ciri khas di permukaannya. Tanah laterit merah muda yang tebalnya lebih dari 25 meter menutupi tubuh granitoid tersebut dan menjadi petunjuk penyebaranya di permukaan, namun penyebaran di bawah permukaannya masih belum pasti. Penelitian ini bertujuan untuk mengetahui penyebaran granitoid di bawah permukaan. Untuk mengidentifikasi tubuh bawah permukaannya, digunakan pemodelan gravitasi dan tomografi seismik. Menurut model gravitasi tubuh pluton mempunyai lebar 5 km dan tampak memanjang ke arah timur yang tidak menentu ke bawahnya. Sementara itu, model tomografi seismik utara-selatan yang memotong wilayah Pacitan, menunjukkan suatu tubuh padat keras berada di atas zona subduksi Jawa saat ini. Tubuh tersebut diasumsikan memiliki hubungan dengan batuan granitik di permukaan. Hal tersebut mendukung ide bahwa terdapat mikro-kontinen terperangkap di bawah Pegunungan Selatan Jawa Timur.
Rosetta Stone for Language Learning
Authors: Lord Gillian
Published: February 2019

The Rosetta Stone program advertises that it can teach language as effectively as, or even more effectively than, a typical classroom-learning environment. Little research has examined this claim, but as institutions are asked to cut costs and simultaneously embrace digital technologies, these programs are often considered as a possible solution to potentially replace teachers or other personnel. This exploratory multiple case study examines the claims and learning outcomes of the Rosetta Stone program among beginning Spanish learners to assess the effects of a semester-long treatment in which participants used Rosetta Stone as their class textbook or alone (instead of any class attendance), as compared to a control group. Data analysis focuses on learner outcomes in terms of linguistic production as well as their attitudes about the materials. Results reveal qualitative differences characterizing learners’ speech and strategies, as well as their reactions to the program. While continued investigation is needed, these initial results do not yet provide indication that the Rosetta Stone program, although possibly able to deliver success in some areas, would be capable of replacing the classroom language learning experience.
Hypertext versus Footnotes
Authors: Ebsworth Miriam Eisenstein , McDonell Tommy , DeFazio Anthony , Cai Chencen
Published: February 2019

This study considers forty adolescent English Language Learners who read a passage online containing additional information available through either hypertext links or footnotes. Participants were attending a special high school for English learners at the time of the study. Two versions of the text were offered, one with hypertext and the other with footnotes, and participants were randomly assigned to the footnote or hypertext condition. Answers to multiple choice questions showed no significant difference between groups in recall of the reading under the two conditions, in contrast with an earlier study of learners in higher education settings whose recall of reading with hypertext was significantly lower than with footnotes. Learners’ ratings of perceived comprehensibility of the 2 texts was also not significantly different. Additional interpretive data came from focus group interviews involving all of the participants.
Stratification of Domains Using Composite Estimation to Measure the Revenue Level of Small Businesses in Poland
Authors: Dehnel Grażyna
Published: February 2019

To meet the growing demand for detailed, precise, accurate and timely estimation of entrepreneurship and economic conditions, it is necessary to systematically extend the scope of information provided by business statistics. In view of the policy aimed at reducing survey costs and burdens for business units, the only way in which this objective can be achieved is by modernizing survey methodology. One area where this kind research is being conducted are applications of indirect estimation based on auxiliary sources of information from administrative sources. Hence, the purpose of the study described in this article is to evaluate the precision of estimates of revenues of small businesses for domains defined by spatial aggregation and business classification by applying stratification in composite estimators based on information collected from administrative registers.
Dane w chmurze czy dane zlinkowane?
Authors: Nahotko Marek
Published: February 2019

Two phenomena related to the functioning of libraries in a wide area network were compared: cloud library and Linked Open Data. Both of these phenomena are intertwined, but they are different. They are linked by the tendency to move everincreasing amounts of data into the Web environment. A new way to include the metadata to the cloud is Linked Open Data. It is about putting all the metadata in the OPEN network: bibliographic descriptions, authority files, dictionaries of all kinds (for example subject headings vocabularies). These data, after appropriate processing (RDF syntactic), form a global metadata cloud, which greatly changes how the Internet functions as an information environment, including the role of libraries.
Usługi biblioteczne w dobie cloud computing – technologia, dane, sieciowe, społeczności informacyjne
Authors: Firlej-Buzon Aneta
Published: February 2019

This text refers to the application of cloud computing technology in modern libraries, with particular emphasis on large academic institutions. Based on the experiences of the Library of Congress, benefits from the use of cloud services by libraries and recommendations for the secure use of cloud technology. Networking of cloud-based information communities contributes to the growth of book and reader promotion, library support, and book development.
Chmura w bibliotece jako lekarstwo na chmury nad biblioteką na przykładzie bibliotek pedagogicznych
Authors: Wachowicz Monika
Published: February 2019

Using the cloud computing has become universal nowadays. It permeated into private and professional life. The article presents examples of the ways of using cloud computing on various types of devices by teacher-librarians. The author assumes that cloud computing can solve problems related to the implementation of statutory tasks of libraries in some situations. Services available in the cloud are investigated by informatologists and topics trainings are often organized, both by librarians and for librarians. According to the author, working in the cloud does not pose a threat to the identity of the pedagogical library, but it is only a new tool to support activities of such an institution. Farthermore, cloud computing should be assumed with the knowledge of its capabilities and limitations.
Biblioteka akademicka – płaszczyzny ewolucji
Authors: Kazan Anna , Skubała Elżbieta
Published: February 2019

„Do libraries more and more lose their tangible form and, through entering the virtual world, lose an established identity…?” For one, the answer to a question given in the conference agenda is obvious and unambiguous, with a hint of nostalgia and pejorative evaluation – yes! For others, the positive answer means progress, up-todateness and service quality of library, which in common perception still remains a symbol of „traditional” institution. The range of changes regarding higher schools libraries, following technical development and users expectations, is huge and concerns not only the merits, but also finances, accounting, inventory of the property or human resources managment. Ultimately the mission of an academic library and its role at the university may change. With some of those changes librarians are already familiar and therefore – ready for the effects. But some of those modifications may still be surprising. In the article we will analyse some of the library activities, which – due to technological evolution – are transfered to virtual world. We will also try to guess a direction in which academic libraries should begin to change.
Miejsce bibliotek w erze transformacji prasy
Authors: Felińska Renata
Published: February 2019

Journals of high, medium and low input consist significant par t of library collection. They play also an important role in formation of society's culture. Press is not the basic source of knowledge and information, but as Polish Studies on Reading (PSR) indicates, for majority of readers, it the most valuable resource of content. Values such as professionalism, honesty, authority, reliability and intelligence are associated with the image of press. For many readers digital version of press becomes more attractive form of expression. More and more titles that traditionally were issued in paper form, now are digitalized. Report from PSR studies shows growth of interest in reading digital press. At the same time these studies show that their range of influence should grow. Report about diagnosis of reader’s behaviors in relation to press does not show optimist vision for sharing press in libraries. However, both analyst’s and librarians’ observations of publishing market give hope that for many years to come printed press will source of knowledge and social opinion. Libraries also have the ability to offer digital press that readers find interesting.
Standaryzacja opracowania zbiorów w bibliotece akademickiej
Authors: Knop Urszula
Published: February 2019

The article presents changes in the standardization of cataloging library collections on the example of cataloging books in the OPACs in libraries cooperating with NUKAT (central catalog of scientific libraries) and cataloging of periodicals in electronic databases in the project “Central Open Science Library”. The direction of changes in the standardization of cataloging of library collections and the reason why it plays a special role in customer service, are just some of the problems that the author has taken in this article. The problems described in the article do not reflect the whole overview of the situation, they only indicate trends associated with dynamic changes in cataloging of scientific collections, which are important in customer service.
Analiza przestrzeni informacyjnej Biblioteki Uniwersytetu Gdańskiego
Authors: Kulczycka Urszula
Published: February 2019

The modern world is dominated by information, the importance of which is constantly growing. To say that members of the modern society are living in information`s environment is truism, but most important thing in the communication process is commitment of technology. This increases the importance of digital competence and increases the aspirations of society in respect of access to knowledge in a fast, easy and convenient way. Contemporary infospace, especially virtual, is more and more complex, dynamic and scattered. An example of such space mighty be online digital libraries, databases, and catalogs. This article discusses how the Library of the University of Gdańsk is now making an attempt to respond to or client`s needs.
Gubernamentalidad: de la tradición biopolítica a la tradición gubernamental
Authors: Ocampo Giraldo Hernán Dario
Published: February 2019

El propósito de este comentario sobre la tradición biopolítica es ayudar a aclarar, a los lectores nuevos en estas cuestiones, el panorama general y la ruta que se ha trazado en torno a los análisis de esta tecnología que describió Foucault. En este artículo se sostiene que hay, al menos, cuatro momentos claramente identificables dentro de la tradición biopolítica, y tres dentro de la tradición gubernamental, ambas tradiciones están asociadas al contexto social que demanda nuevas teorías para analizar el presente, así como a la divulgación de esas teorías. También se traza aquí una grilla de inteligibilidad entre la biopolítica y la gubernamentalidad.
La formación integral: una apuesta de la educación superior
Authors: Nova Herrera Adriana Judith
Published: February 2019

Con base en las leyes 30 de 1992 y 115 de 1994, la misión de la educaciónsuperior en Colombia es formar integralmente al ser humano, esta tarea esasumida por las instituciones de educación superior, pero, a diferencia de lainvestigación y los saberes técnicos, es difícil identificarla en la práctica. Laformación humana de Kant y Locke fundamentan la formación integral, y lavisión contemporánea de esta se apoya en los planteamientos de Rincón, Orozco,Campo y Restrepo y Zazar, quienes afirman que el fin de la educación es llevaral ser a alcanzar su humanización, a partir del desarrollo de su condición ynaturaleza, para lograr formar personas plenamente desarrolladas y sociedadesmás justas y pacíficas. Pero a la educación superior se le delegan múltiplesresponsabilidades que la desvían de su fin. Este artículo presenta una revisión de teorías que se enmarcan desde el período de la Ilustración hasta finales delsiglo XX, junto con algunos documentos gubernamentales. Este proceso serealizó a través de una conceptualización teórica, asumida como una primerafase del análisis de contenido cualitativo que se aplica en el proyecto «Límites yalcances de la formación integral en la UPTC. Sede Tunja 2008-2010». Elpresente documento evidencia la necesidad de una visión de educación superiormás integradora. Se destaca la importancia de incluir las corrientes humanistasen la relación enseñanza-aprendizaje.
Del conocimiento histórico al conocimiento escolar. Planificación docente para la enseñanza de Historia y Ciencias Sociales
Authors: Castañeda Meneses Marta Cecilia
Published: February 2019

El conocimiento histórico se enfrenta al desafío de convertirse en saber escolar. Este proceso se inicia con las decisiones curriculares ministeriales sobre el qué enseñar y se concreta en el aula escolar a partir de las decisiones profesionales de los docentes. En ese contexto, el artículo da cuenta de los procesos de planificación que para la asignatura de historia realizan estudiantes en práctica profesional y profesores noveles de una universidad pública y regional chilena. Como opción metodológica de investigación se utiliza el Estudio de Casos. Los casos se construyen teniendo como eje la enseñanza de conceptos sociales, a partir de entrevistas, observaciones de clases y análisis de documentos. Entre las principales conclusiones se puede mencionar, que los procesos de planificación están directamente relacionados con el dominio conceptual y disciplinar del docente, que existe una autonomía relativa en los procesos de planificación principalmente dada por el contexto, y que se reconocen limitaciones metodológicas y externas al proceso de planificación que desarrollan ambos colectivos. La presencia de los conceptos sociales en los procesos de planificación es prioritariamente implícita, priorizándose los hechos por sobre las revisiones conceptuales.
Los sobrevivientes del Holocausto en Argentina durante la Guerra de los Seis Días en Medio Oriente (1967)
Authors: Kahan Emmanuel Nicolás
Published: February 2019

El presente trabajo pretende, en primer lugar, reconstruir las acciones desarrolladas por Sherit Hapleitá , la Asociación de sobrevivientes de la persecución nazi en Argentina, durante los días en que tuviera lugar la Guerra de los Seis Días en Medio Oriente. En segundo término, el artículo se propone analizar cómo operó una narrativa «argentina» en torno a la experiencia y sobrevivencia del nazismo como discurso legitimador de las acciones y de la propia existencia de Israel. En este sentido, las intervenciones de los sobrevivientes del Holocausto resultaron significativas, pues tuvieron lugar en un contexto nacional en el que las narrativas de la derecha nacionalista y las organizaciones de izquierda en proceso de radicalización cuestionaban la lealtad de los judíos a la nacionalidad argentina, así como la legitimidad del sionismo como adscripción política. La investigación se desarrolló en torno al fondo documental de quien fuera el presidente de la organización y del relevamiento de prensa del período.
Biodiversité des macrochampignons sauvages comestibles de la forêt humide du Sud-Cameroun
Authors: Onguene Awana Nérée , Tchudjo Tchuente Armelle Nadine , Kuyper Thomas W.
Published: February 2019

Pour les communautés de forêts humides du Cameroun – Bantu, pygmées Baka et Bagyeli –, les champignons sauvages comestibles (CSC) ont toujours été considérés comme de substantielles sources alimentaires et médicinales. Cependant, peu d’informations sont disponibles sur la diversité et l’écologie des CSC du Cameroun. Aussi une étude a-t-elle été entreprise pour connaître la diversité et acquérir les connaissances endogènes des principaux champignons sauvages comestibles et médicinaux de la forêt humide de ce pays. À partir d’excursions mycologiques, d’enquêtes structurées et semi-structurées conduites dans une vingtaine de sites de cinq régions du Grand-Sud-Cameroun, les espèces de CSC ont été collectées et décrites. Quatre-vingt-quatorze taxons de CSC ont été identifiés, appartenant à 32 familles et 41 genres, dont environ 61,7 % de saprotrophes, 21,3 % de taxons ectomycorhiziens (ECM) et 17 % d’espèces du genre Termitomyces, les plus fréquemment collectées et consommées. Cette forte diversité fongique s’est traduite par un éventail varié d’habitats et de niches écologiques. Les CSC les plus appréciés sont les saprotrophes Armillaria camerounensis et Volvariella volvacea, ainsi que toutes les espèces de Termitomyces et de chanterelles. La plupart de CSC sont collectés pour la consommation. La vingtaine d’espèces de CSC ectomycorhiziens sont symbiotiquement associées aux racines de 13 genres d’essences forestières appartenant aux familles des Cesalpiniaceae et Phyllantaceae. In fine, deux principaux services écosystémiques de production sont fournis par les CSC du Cameroun : l’approvisionnement alimentaire et médicinal, et l’octroi de revenus. Des besoins de recherche s’imposent en faveur de l’étude de la biodiversité et des médicinaux des CSC de la forêt humide du Cameroun, et de la valorisation des déchets agricoles pour la culture du champignon de paille V. volvacea.
Banque de graines du sol et déterminants de la germination du tali, Erythrophleum suaveolens (Guill. & Perr.) Brenan
Authors: Douh Chauvelin , Gorel Anaïs-Pasiphaé , Daïnou Kasso , Fonteyn Davy , Bustillo Esther , Obsomer Louise , Bourdouxhe Axel Bourdouxhe , Morin-Rivat Julie , Forni Éric , Gourlet-Fleury Sylvie , Loumeto Jean Joël , Doucet Jean-Louis
Published: February 2019

Cette étude évalue l’abondance des graines d’Erythrophleum suaveolens dans la banque de semences du sol des forêts denses humides d’Afrique centrale. Les travaux ont été menés au Nord-Congo dans deux types forestiers : la forêt à Celtis sur des sols argilo-sableux à sablo-argileux et la forêt à Manilkara sur des sols sableux. Les tiges d’E. suaveolens (dhp ≥ 10 cm) ont été inventoriées dans deux blocs de 400 ha, et les structures diamétriques de leurs populations ont été comparées. En outre, 80 fosses (2 x 40 fosses par type de forêt) ont été creusées au pied de 20 arbres (10 par forêt), sur trois couches contiguës de 10 cm chacune, soit à une profondeur totale de 30 cm, et l’abondance des graines dans la banque de semences du sol a été évaluée. La dormance des graines récoltées a été testée par des essais de germination après traitement au H2SO4 et cinq graines prélevées jusqu'à une profondeur de 20 cm dans la forêt à Celtis ont été utilisées pour estimer leur âge par spectroscopie de masse par accélérateur (AMS). Dans les deux types forestiers, les structures diamétriques présentent une distribution gaussienne, illustrant un déficit de régénération. Alors que les densités de tiges (dhp ≥ 10 cm) sont proches, avec 0,85 et 1,05 tige/ha respectivement, dans la forêt à Celtis et la forêt à Manilkara. Les densités de graines sont significativement plus élevées dans la forêt à Celtis (8,55 graines/m2) que dans la forêt à Manilkara (0,15 graine/m2). Le pourcentage maximum de germination obtenu était de 19,1 % pour des graines n’ayant subi aucun traitement. Les lots traités à l’acide ont présenté de moindres taux de germination. Ces graines semblent pouvoir se conserver une dizaine d’années au moins dans la banque du sol. Les facteurs pouvant influencer les variations de densité des graines sont discutés et des recommandations sylvicoles sont formulées.
Entropia e energias de Helmholtz e de Gibbs
Authors: Bassi Adalberto B. M. S.
Published: February 2019

Tradicionalmente, o conceito de entropia só existe para o equilíbrio, o que exige o mesmo para as energias de Helmholtz e de Gibbs, porque estas são definidas a partir dele. Como conseqüência, toda a termodinâmica acaba restrita ao equilíbrio, embora ela inclua grandezas costumeiramente chamadas mecânicas, como o volume e a energia interna, as quais são consideradas existentes mesmo fora do equilíbrio. Por esta razão, a termodinâmica é a única ciência natural que é proclamada atemporal. Porém, desde que esta imposição foi colocada, ainda no século XIX, alguns pesquisadores contra ela se rebelaram. A moderna termodinâmica dos meios contínuos, da qual a termodinâmica dos meios homogêneos é a teoria introdutória, traz nova luz sobre esta antiga polêmica. No presente trabalho, a interpretação dada por Boltzman e Planck, que jamais aceitaram restringir o conceito de entropia a estados de equilíbrio, é defendida por meio de idéias atuais.
Espectroscopia de luminescência
Authors: Atvars Teresa D. Z. , Martelli Cláudia
Published: February 2019

Esta matéria apresenta, sucintamente, os princípios teóricos da espectroscopia de luminescência de moléculas orgânicas, a partir de um estado eletrônico excitado. Para isto apresenta uma breve revisão sobre os processos de absorção, sobre a estrutura vibracional das transições eletrônicas e sobre a dependência da intensidade de luminescência com a concentração da amostra. Traz os esquemas e a descrição dos principais tipos de processos envolvidos após a excitação molecular sob condições fotoestacionárias (excitação com uma fonte contínua). Aborda alguns exemplos e os principais tipos de informações moleculares que podem ser obtidos a partir deste tipo de espectroscopia. Os aspectos experimentais relacionados às medidas de espectroscopia de fluorescência sob condições fotoestacionárias estão tratados em outro texto.
Funções de base: o ajuste variacional
Authors: Morgon Nelson Henrique , Custódio Rogério
Published: February 2019

Dentre os modelos matemáticos utilizados para representar a estrutura eletrônica de sistemas microscópicos um dos mais valiosos é o modelo de Hartree-Fock [1]. O maior problema a ser resolvido neste modelo está na escolha das funções matemáticas a serem utilizadas para representar os orbitais de Hartree-Fock. Uma das sugestões mais importantes ao método Hartree-Fock foi formalizada por J.J.Roothaan através da técnica que ficou popularizada como o método da combinação linear de orbitais atômicos ou funções de base [2]. Em outras palavras, orbitais atômicos e moleculares podem ser obtidos como combinação linear de funções de base. Embora o modelo de Hartree-Fock-Roothaan tenha se tornado computacionalmente atrativo, para ser utilizado adequadamente impõem a solução de questões de caráter técnico, tais como: quais funções matemáticas podem ser utilizadas como conjuntos de base? e quantas funções de base devem ser utilizadas para representar adequadamente o sistema em estudo?
Espectroscopia eletrônica de absorção
Authors: Atvars Teresa D. Z. , Martelli Cláudia
Published: February 2019

Esta matéria apresenta, sucintamente, os princípios de funcionamento de espectrofotômetros para a obtenção de espectros eletrônicos de absorção, na região espectral do ultravioleta ao infravermelho próximo. Traz os esquemas e a descrição de instrumentos de mono e duplo feixes, bem como daqueles com detectores do tipo arranjo de diodos e fotomultiplicadoras. Esse texto será complementado por um outro, que descreverá o princípio de funcionamento de espectrofotômetros para a obtenção de espectros eletrônicos de emissão e de excitação em condições fotoestacionárias, normalmente chamados de espectrofluorímetros.
Lei dos processos de absorção da radiação
Authors: Custodio Rogério , Kubota Lauro T. , Andrade João Carlos de
Published: February 2019

A radiação eletromagnética que uma amostra absorve pode revelar algumas de suas características. A Lei de Beer estabelece uma relação linear entre a absorbância e a concentração da amostra, sendo portanto, possível determinar a concentração de uma amostra através de sua curva de calibração (absorbância versus concentração).
Segurança no laboratório químico
Authors: Coscione Aline Renée , Almeida Alex Magalhães de , Andrade João Carlos de , Custodio Rogério
Published: February 2019

No texto abaixo estão relacionados itens elementares para sua segurança no laboratório químico. Incorpore-os em seu procedimento habitual ao enfrentar um dia de trabalho.
Método LCAO
Authors: Custodio Rogério , Morgon Nelson Henrique
Published: February 2019

Orbitais atômicos e moleculares podem ser obtidos como uma combinação linear de funções de base. Este modelo ficou conhecido como método da combinação linear de orbitais atômicos (do inglês: Linear Combination of Atomic Orbitals), sendo uma das técnicas mais utilizadas para o cálculo de propriedades eletrônicas de átomos, moléculas, etc., por métodos quânticos. Neste texto serão abordados alguns dos aspectos fundamentais para o cálculo de propriedades eletrônicas através do método denominado Hartree-Fock-Roothaan, que corresponde à aplicação da combinação linear de orbitais atômicos usando o modelo Hartree-Fock.
Quantidade de matéria e concentração
Authors: Andrade João Carlos de , Custodio Rogério
Published: February 2019

O presente artigo apresenta as definições de quantidade de matéria, mol e concentração, além das várias unidades aceitas pelo Sistema Internacional para concentração.
Normas de segurança do IQ / UNICAMP
Authors: UNICAMP Instituto de Química
Published: February 2019

As Normas de Segurança do Instituto de Química da Universidade Estadual de Campinas determinam os requisitos básicos para a proteção da vida e da propriedade nas suas dependências, onde são manuseados produtos químicos e equipamentos. Essas normas se aplicam a todas as pessoas alocadas no Instituto de Química e também àquelas que não estejam ligadas ao mesmo, mas que tenham acesso ou permanência autorizadas às suas dependências.
Normas do laboratório de reações perigosas
Authors: UNICAMP Instituto de Química
Published: February 2019

Todos os cuidados necessários para a utilização do Laboratório de Reações Perigosas, assim como as normas que devem ser seguidas e os termos de responsabilidade que devem ser entregues à Comissão de Segurança do Instituto de Química da Unicamp, são aqui apresentados.
Cromatografia a gás: curso em diapositivos
Authors: Augusto Fábio
Published: February 2019

A separação e análise de misturas de substâncias voláteis podem ser feita por meio da Cromatografia Gasosa (CG). O uso desta técnica exige alguns cuidados, dentre eles a escolha correta da fase estacionária (FE) e da fase móvel (FM). A temperatura deve ser também controlada, para assegurar a reprodutibilidade das análises. Estes e outros pontos críticos da técnica de Cromatografia Gasosa serão abordados neste artigo.
Matemática e termodinâmica
Authors: Bassi Adalberto B. M. S.
Published: February 2019

Matemática e Termodinâmica parecem imiscíveis. Os termodinamicistas adotam uma matemática própria que, para reencontrar a ciência a que os atuais matemáticos se dedicam, precisa retornar em mais de um século no tempo. Os matemáticos dificilmente se interessam por termodinâmica e, quando o fazem, produzem trabalhos de difícil compreensão para os termodinamicistas. Embora ambos pareçam muito bem acomodados nesta situação, a evolução científica, inevitavelmente, perturbará esta tranqüila convivência.
Química analítica básica: uma visão histórica da análise qualitativa clássica
Authors: Andrade João Carlos de , Alvim Terezinha Ribeiro
Published: February 2019

A história mostra que nada é totalmente novo e que por isso o antigo não deve ser descartado e sim conhecido para que novos conhecimentos sejam construídos. Assim, quando entrevistado por Rudy M. Baum, Henry Taube, Prêmio Nobel de Química de 1983, disse que foi um erro o desaparecimento da análise qualitativa dos currículos das universidades norte-americanas, porque esta constituía um meio de introduzir a química descritiva e de motivar os alunos a estudarem as reações químicas que, em sua opinião, “são o coração da química” [1]. Em vista desta polêmica e das possíveis opções para o emprego da disciplina de Química Analítica Qualitativa como ferramenta para o ensino básico dos equilíbrios químicos em solução aquosa, apresenta-se a seguir uma visão crítica da seqüência histórica do desenvolvimento dos procedimentos de análise qualitativa.
Química analítica básica: o papel da química analítica clássica na formação do químico
Authors: Andrade João Carlos de , Alvim Terezinha Ribeiro
Published: February 2019

O conteúdo programático da Química Analítica Qualitativa Inorgânica geralmente usado pelas Instituições de Ensino Superior (I.E.S.) brasileiras compreende a teoria do equilíbrio químico em solução aquosa e, na parte prática, a separação e identificação de cátions e ânions em solução ou em amostras sólidas, empregando os métodos clássicos. Como ainda se convive com opiniões favoráveis e contrárias à manutenção da Química Analítica Qualitativa clássica nos currículos dos cursos superiores de Química brasileiros, pretende-se fornecer elementos que demonstrem a importância do ensino da pesquisa de cátions e ânions na formação do químico no Brasil, como base fundamental para o ensino da Análise Quantitativa e da Análise Instrumental.
Swap-Driven Self-Adhesion and Healing of Vitrimers
Authors: Ciarella Simone , Ellenbroek Wouter G.
Published: February 2019

Vitrimers are covalent network materials, comparable in structure to classical thermosets. Unlike normal thermosets, they possess a chemical bond swap mechanism that makes their structure dynamic and suitable for activated welding and even autonomous self-healing. The central question in designing such materials is the trade-off between autonomy and material stability: The swap mechanism facilitates the healing but it also facilitates creep, which makes the perfectly stable self-healing solid a hard goal to reach. Here, we address this question for the case of self-healing vitrimers made from star polymers. Using coarse-grained molecular dynamics simulations, we study the adhesion of two vitrimer samples and find that they bond together on timescales that are much shorter than the stress relaxation time. We show that the swap mechanism allows the star polymers to diffuse through the material through coordinated swap events, but the healing process is much faster and does not depend on this mobility.
The Effect of Humidity on the Electrical Resistance of Smart Sensor Based on Carbon Fibers
Authors: Górski Marcin , Krzywoń Rafał , Kekez Sofija
Published: February 2019

The paper describes preliminary studies on the influence of humidity on the electrical resistance of a textile sensor made of carbon fibers. The concept of the sensor refers to externally bonded fiber reinforcement commonly used to strengthen building structures. However, the zig-zag arrangement of carbon fiber tow allows measuring strains, as it is done in popular resistive strain gauges. The sensor tests proved its effectiveness in the measurement of strains, but also showed a high sensitivity to changes in the temperature and humidity which unfavorably affects the readings and their interpretation. The influence of these factors must be compensated. Due to the size of the sensor, there is not possible electrical compensation by the combining of several sensors into the half or full Wheatstone bridge circuit. Only mathematical compensation based on known humidity resistance functions is possible. The described research is the first step to develop such relations. The tests were carried out at temperatures of 10 °C, 20 °C and 30 °C, with changing the humidity in the range of 30-90%.
The Global Legal Entity Identifier System: How Can It Deliver?
Authors: Milne Alistair , Chan Ka Kei
Published: February 2019

We examine the global legal entity identifier (LEI) system for the identification of participants in financial markets. Semi-structured interviews with data professionals reveal the many ways in which the LEI can improve both business process efficiency and counterparty and credit risk management. Larger social benefits, including monitoring of systemic financial risk, are achievable if it becomes the accepted universal standard for legal entity identification. Our interviews also review the substantial co-ordination and investment barriers to LEI adoption. To address these, a clear regulatory-led road map is needed for its future development with widespread application in regulatory reporting.
The Influence of Reputation of Public Accounting Firms on the Integrity of Financial Statements with Corporate Governance as the Moderating Variable
Authors: Machdar Nera Marinda , Nurdiniah Dade
Published: February 2019

This research aimed to determine the effect of the reputation of the public accounting firm on the integrity of financial statements by including leverage and firm size as the control variables. This research also investigated the effects of corporate governance moderation that was proxied by the independent commissioner, institutional ownership, and audit committee in strengthening or weakening the reputation of the public accounting firms on the integrity of the financial statements. The population was manufacturing companies listed on the Indonesia Stock Exchange (IDX) in 2013-2015. The sample utilized the purposive sampling method and resulted in 34 manufacturing firms, so the total observations were 102 firms in all observed years. This research performed statistical data processing with EVIEWS 8. There are two main findings of this research. First, the reputation of public accounting firm affects the integrity of the financial statement. Second, corporate governance that utilizes the independent commissioners and institutional ownership strengthen the effect of the reputation of the public accounting firm on the integrity of the financial statement. However, corporate governance using audit committee weakens the reputation of the public accounting firm on the integrity of financial statements.
Exploratory Factors Analysis of Employee Retention at Tertiary Educational Institution: A Case Study of a Private University in East Indonesia
Authors: Tansuria Billy Ivan , Nelwan Melinda Lydia
Published: February 2019

This research aimed to identify the factors that contributed to the employee retention in the tertiary educational institution in Indonesia. The researchers used a case study of a private university in East Indonesia. This research was an exploratory factor analysis research. The items generated from in-depth interviews were developed into a questionnaire and distributed to 165 employees of the particular university based on purposive sampling method. About 105 respondents were obtained. The researchers utilized SPSS to analyze the data. The result shows that performance management function, organizational culture, employee engagement, social support, and work environment are the main factors contributing to the employee retention in the university. Among those factors, the performance management function is the factor with the highest factor loading.
Modeling of Tourist Satisfaction in Bali
Authors: Adinegara Gusti Ngurah Joko
Published: February 2019

This research provided the new results on the determinants of tourist satisfaction. The data were obtained using questionnaire as the instrument. The variables used were destination and hotel service quality, destination and hotel image, tourist perceived value, tourist satisfaction, revisit intention, and word of mouth. Sampling technique was convenience sampling. The respondents were foreign and domestic tourists who traveled to Bali and stayed at three and four-star hotels. The sample size was 265. Then, the Structural Equation Modeling (SEM) was utilized in explaining the relationship between latent variables and hypotheses. The result shows that from eleven hypotheses, there are two rejected hypotheses regarding the influence of destination service quality and hotel service quality on the image. Destination and hotel image has a significant effect on revisit intention and word of mouth through tourist perceived value and satisfaction. Theoretically, tourist satisfaction determines the factors that affect it directly and indirectly. Practically, tourism business should manage the destination and hotel service quality because it increases the tourist perceived value.
Performance Analysis on IEEE 802.11ah Standard with Enhanced Distributed Channel Access Mechanism
Authors: Oktaviana Ana , Perdana Doan , Negara Ridha Muldina
Published: February 2019

IEEE 802.11ah is a new task group on the IEEE 802.11 standard designed to work on the 900 MHz. It is with a range of communication coverage up to 1kilometer, lower energy consumption, and up to 8191 stations. There are two types of STAs in 802.11ah: sensor type to support sensor service and non-sensor type for offload service. In this research, it only focuses on non-sensor STA. For non-sensor STA, maximizing throughput is more important than power consumption. This research aims to see the performance of IEEE 802.1 1ah with Enhanced Distributed Channel Access (EDCA). To achieve that purpose, a mechanism is needed to provide guarantees various services required by theSTA. EDCA is an access mechanism used to set the Quality of Service (QoS) for the IEEE 802.11 standard through modifications in MAC layer. In this research,it focuses on one of the EDCA parameters, Arbitration Inter-Frame Space (AIFS). In addition, this research also focuses on the 802.11ah feature is Restricted Access Window (RAW) by changing the number of the RAW groups. From the results of the research, it is found that the improvement scheme with Arbitration Inter-Frame Space Number (AIFSN) value AC BK = 2, AC BE = 1, AC VI = 1, AC VO = 1 has better performance compared to the default scheme with AIFSN value AC BK = 7, AC BE = 3, AC VI = 2, AC VO = 2) with an average throughput of 1.504598 Mbps, average overall delay of 0.066242 second and average PDR of 62%. In addition, changes in the number of RAW groups and RAW slots affect network performance. This feature can improve the value of throughput, average delay, and Packet Delivery Ratio. The goals of this research is to know the effect of AIFSN value changes on AIFSN parameters, variation of RAW group and RAW slot number to throughput,average delay and packet delivery ratio.