984 resultados para Table of Contents
Resumo:
BACKGROUND: Direct colonic electrical stimulation may prove to be a treatment option for specific motility disorders such as chronic constipation. The aim of this study was to provoke colonic contractions using electrical stimulation delivered from a battery-operated device. METHODS: Electrodes were inserted into the caecal seromuscular layer of eight anaesthetized pigs. Contractions were induced by a neurostimulator (Medtronic 3625). Caecal motility was measured simultaneously by video image analysis, manometry and a technique assessing colonic transit. RESULTS: Caecal contractions were generated using 8-10 V amplitude, 1000 micros pulse width, 120 Hz frequency for 10-30 s, with an intensity of 7-15 mA. The maximal contraction strength was observed after 20-25 s. Electrical stimulation was followed by a relaxation phase of 1.5-2 min during which contractions propagated orally and aborally over at least 10 cm. Spontaneous and stimulated caecal motility values were significantly different for both intraluminal pressure (mean(s.d.) 332(124) and 463(187) mmHg respectively; P < 0.001, 42 experiments) and movement of contents (1.6(0.9) and 3.9(2.8) mm; P < 0.001, 40 experiments). CONCLUSION: Electrical stimulation modulated caecal motility, and provoked localized and propagated colonic contractions.
Resumo:
In the preparation of this compilation of drainage laws of Iowa, an attempt has been made to include those sections of the Code to which reference is frequently required by the State Highway Commission, Boards of Supervisors and County Engineers in the conduct of highway and road administration as it is affected by the Iowa drainage laws. Of necessity some Code provisions which have a bearing on the principal subject were omitted. Enactments of the 56th General Assembly which modify existing code sections have been included as part of the regular text of the Code sections included in this publication. THE USER IS CAUTIONED THAT THESE CODE SECTIONS, AS MODIFIED BY THE 56th GENERAL ASSEMBLY, ARE NOT A PART OF THE 1954 CODE OF IOWA AND ARE OFFICIAL ONLY INSOFAR AS THEY ARE PRINTED IN THE OFFICIAL PUBLICATION ACTS OF THE 56TH GENERAL ASSEMBLY. SINCE THE 57TH GENERAL ASSEMBLY IS IN SESSION DURING THE PRINTING OF THIS PUBLICATION, ENACTMENTS OF THAT BODY WHICH AMEND OR REPEAL SECTIONS SET OUT HEREIN ARE INCLUDED IN THE BACK OF THIS VOLUME ON THE PINK-COLORED PAPER. THE USER IS CAUTIONED IN USING THIS VOLUME TO REFER TO THE TABLE OF SECTIONS REPEALED OR AMENDED, ON THE PINK-COLORED PAPER AT THE BACK OF THIS VOLUME. This publication is offered with the hope and belief that it will prove to be of value and assistance to those concerned with the problems of administering a highway, road and drainage system.
Resumo:
El artículo presenta el panorama actual de las nuevas tecnologías en el mundo de la educación.Del potencial que presentan las nuevas tecnologias y concretamente los dispositivos móviles, nace el proyecto KPAX, una plataforma tecnológica que soporte la incorporación de módulos independientes de aprendizaje basado en juegos.Wit Quiz es un caso práctico de dicho proyecto. Es un juego que integra las nuevas tecnologías con nuevas formas de aprendizaje informal. Se ha optado por una primera implementación sobre Iphone debido al éxito creciente de sus apps.La aplicación Wit Quiz ha sido desarrollada con cocoa, xcode y objective-c y permite una fácil gesión de sus contenidos gracias a la implementación de un servicio web.
Resumo:
Tutkielman pääaiheena on asunto-osakkeiden kauppa. Keskeisimpänä tutkimusaiheena on myyjän asemesta korjausrakentamiseen painottuva näkökulma. Tutkielman tarkoituksena on analysoida omistuksen, statuksen ja päätöksenteon vaikutusta myyjän vastuisiin. Tutkielmassa pyritään myös selvittämään asunto-osakeyhtiön omistuspohjan merkitystä elinkeinonharjoittajana toimivan osakkaan vastuisiin. Metodina käytetään vertailevaa tutkimusotetta, painottuenosaltaan kausaliteettiin. Teemaa koskevan analyysin avulla pyritään lainsäädännön sisältä tulkitsemaan ja selkeyttämään asuntokauppaan liittyviä ongelmia. Praktisen lähestymistavan avulla pyritään tuottamaan viitekehys, joka palvelee voimassaolevan normatiivisen tiedon kehittämistä. Tutkielma osoittaa, että lainsäädäntö on jakautunut asunto-osakkeiden kaupan näkökulmasta tavalla, jota voidaan kritisoida. Asuntokauppalaissa sääntely ei kohdistu tilanteisiin, joissa huomioitaisiin korjausrakentamisen moniulotteisuus. Pikemminkin käytännön näkökulmasta on nähtävissä suunta, jossa korostetaan tiedon merkitystä osanavaihdantaa jopa sisällön ja validiteetin kustannuksella
Resumo:
El objetivo de este trabajo fue el de evaluar la deposición transversal de caldo de las boquillas pulverizadoras de doble abanico TTJ60-11004 y TTJ60-11002 en distintas condiciones operacionales. Se utilizaron 5 muestras de cada boquilla pulverizadora siendo considerada cada unidad, una repetición. La distribución de caldo fue evaluada por medio de una mesa de evaluación de distribución construida de acuerdo con la norma ISO 56821. Se evaluó el perfil de distribución individual, la distribución volumétrica simulada de la superposición de los chorros por medio del coeficiente de variación (CV%) de los volúmenes colectados, el caudal y el ángulo de abertura de los chorros. Las condiciones operacionales fueron: presión de trabajo de 200, 300 y 400 Kpa, altura de 30, 40 y 50 cm en relación al blanco y espaciamiento entre boquillas simulados en Software (Microsoft Excel) entre 45 y 100 cm. Las boquillas presentaron perfil individual descontinuo con la mayor deposición de líquido en la región central y reducción del volumen gradual en dirección a las extremidades. El aumento de la presión promovió alargamiento del perfil y de la franja de aplicación. Las boquillas proporcionaron perfil uniforme que dependió del espaciamiento entre las boquillas, con valores menores con reducción en el espaciamiento y en presiones mayores. El caudal y el ángulo del chorro aumentaron con el incremento en la presión.
Resumo:
Los recursos educativos abiertos son un concepto reciente en lo que respecta a la organización del mundo de intercambio de variedad de materiales y herramientas educacionales, e instituciones como la UNESCO están interesadas en el desarrollo de éstos para ser utilizados en una escala tan amplia y global como sea posible. Sin embargo, los REA cuentan con algunas dificultades para obtener plenamente su eficacia, ya que existen diferencias cruciales en la organización y en la interacción de estas redes abiertas. Este artículo intenta explorar el intercambio libre y legal de los contenidos y su reutilización como recursos de apoyo para el aprendizaje en diferentes espacios en línea, aprovechando las posibilidades tecnológicas que permiten conformar nuevas estructuras de socialización y colaboración en línea; y concluye con una reflexión sobre las barreras que aún tienen que superar los REA para lograr un éxito total.
Resumo:
A history of the periodic table of the elements is presented, from the first tentative classifications, passing through Meyer and Mendeleev, up to recent speculations on super-heavy elements still to be synthesized. Many of the discussions and discoveries related to chemical elements and their proper periodic classification are also presented.
Resumo:
In this paper we identify the requirements for creating formal descriptions of learning scenarios designed under the European HigherEducation Area paradigm, using competences and learning activities as the basic pieces of the learning process, instead of contents and learning resources, pursuing personalization. Classical arrangements of content based courses are no longer enough to describe all the richness of this new learning process, where user profiles, competences and complex hierarchical itineraries need to be properly combined. We study the intersection with the current IMS Learning Design specification and theadditional metadata required for describing such learning scenarios. This new approach involves the use of case based learning and collaborativelearning in order to acquire and develop competences, following adaptive learning paths in two structured levels.
Resumo:
Tutkielman tavoitteena on selvittää kuinka tilintarkastajista tilintarkastuslautakunnalle tehdyt kantelut ovat muuttuneet vuosien 1990–2000 ja 2001–2006 aikana. Tutkimuksen tarkoituksena on tarkastella ovatko kansainvälistymisen aiheuttamat muutokset tilintarkastusta säätelevissä laeissa johtaneet kanteluiden määrälliseen tai laadulliseen muutokseen. Teoreettinen osa tarkastelee tilintarkastusta lainsäädännöllisesti sekä TILA:n tehtäviä tilintarkastusta valvovana elimenä. Empiirinen osa tutkii TILA:lle tehtyjen kanteluiden ratkaisuselosteita vuosien 1990–2000 ja 2001–2006 välillä. Kanteluita tutkitaan sekä määrällisesti että laadullisesti. Tulokset osoittavat että kanteluiden määrässä on tapahtunut muutos; vuosina 2001–2006 kanteluiden määrä on selvästi laskenut. Kanteluiden laadussa, kun sillä käsitetään kanteluiden syy sekä epäilyksen alainen toiminta, ei ole tapahtunut muutosta mutta sanktioiden jakaantumisessa eri toiminnan mukaan puolestaan on tapahtunut muutosta.
Resumo:
A fourteenth century caixa de nuvia (a bride’s case). This article studies a bride’s case, or chest described in the records of a trial that took place in the late fourteenth century, preserved in the Archives of Crown of Aragon. The case was claimed by Eulàlia, a commoner from the region of Barcelona. We study the circumstances of the claim, and then consider the descriptions of the items and the relations between the items and the owner. We stress the structures and the functionality of the chest itself and the meticulous description of contents , mainly second hand household wear and engagement presents. We highlight the relationship between women, especially between the mother and the daughter, and the relationship between these women and their possessions
Resumo:
Although several chemical elements were not known by end of the 18th century, Mendeleyev came up with an astonishing achievement: the periodic table of elements. He was not only able to predict the existence of (then) new elements but also to provide accurate estimates of their chemical and physical properties. This is certainly a relevant example of the human intelligence. Here, we intend to shed some light on the following question: Can an artificial intelligence system yield a classification of the elements that resembles, in some sense, the periodic table? To achieve our goal, we have fed a self-organized map (SOM) with information available at Mendeleyev's time. Our results show that similar elements tend to form individual clusters. Thus, SOM generates clusters of halogens, alkaline metals and transition metals that show a similarity with the periodic table of elements.
Resumo:
Propolis is a resinous hive product collected by honeybees from various plant sources. It has a complex chemical composition, constituted by various phenolic compounds. Extracts of increasing polarity (n-hexane, chloroform, and ethanol) were obtained from a sample of red propolis from the state of Alagoas. Assays were carried out for determination of contents of phenolics, along with antibacterial and antioxidant activities. The EEP, fractions and sub-fractions showed strong biological activities and were related with phenolic the content compounds contents. The sub-fractions were more bioactive than the EEP and fractions, demonstrating that the antioxidant and antibacterial activities are not a result of synergistic effect between the various chemical compounds in propolis.
Resumo:
This work discusses an analytical procedure for analysis of sulfur compounds in treated petroleum refinery gaseous effluents using a sulfur chemiluminescence detector with dual plasma burner (SCD-DP). Calibration was accomplished by using standards and gaseous streams of known concentration of sulfur compounds. The response factors agree with the calibration table of ASTM standard D 5504 (2008). The detection range for sulfur compounds is in μg m-3. The analytical procedure allowed the construction of a chromatographic chart of sulfur compounds present in several refinery gaseous effluents. SO2 was the most difficult compound to be determined because of its high reactivity.
Resumo:
This paper presents the results from the selection and analysis of Ciência Hoje articles published from 2004 to 2009 with the aim to discuss some of their features which can assist teachers in chemistry teaching. Therefore, the articles were analyzed according to their content and format based on an analytical tool proposed by Kawamura and colleagues. The results indicate that this magazine offers a reasonable collection of articles related to chemistry with a variety of contents and approaches.
Resumo:
This paper presents an overview of the development of chemical education as a research area and some of its contributions to society. Although science education is a relatively recent area of research, it went through an expressive development in the last decades. As in the whole world, in Brazil also such development is attested by the expressive number of scientific societies, specialized journals, and meetings with growing attendance in the areas of science education in general and chemical education in particular. Following are the main contributions of research in science education related to chemistry teaching: adoption of teaching-learning principles in chemistry education; contextualization of chemical knowledge; interdisciplinary approach to chemistry teaching; use of the history of science for the definition of contents and for the design of curricula and teaching tools; development of specific disciplines for the initial and in-service training of chemistry teachers; publication of innovative chemistry textbooks by university-based research groups; elaboration of official guidelines for high-school level; and evaluation of chemistry textbooks to be distributed to high-school students by the Brazilian government. In spite of a positive impact of such initiatives, science education in Brazil still faces many problems, as indicated by poor results in international evaluations (such as the Program for International Student Assessment). However, changes in such a scenario depend less on the research in chemical education than on the much-needed governmental initiatives aiming at the improvement of both attractiveness of teaching career and structural conditions of public schools. In conclusion, new government investments in education are necessary for continuing the development of chemistry; moreover, scientific societies and decision makers in educational policies should take into consideration the contributions originated from the chemical education research area.