Water flow in high-speed handpieces

Objectives: This study measured the water flow commonly used in high-speed handpieces to evaluate the water flow's influence on temperature generation. Different flow speeds were evaluated between turbines that had different numbers of cooling apertures. Method and materials: Two water samples were collected from each high-speed handpiece at private practices and at the School of Dentistry at São José dos Campos. The first sample was collected at the customary flow and the second was collected with the terminal opened for maximum flow. The two samples were collected into weighed glass receptacles after 15 seconds of turbine operation. The glass receptacles were reweighed and the difference between weights was recorded to calculate the water flow in mL/min and for further statistical analysis. Results: The average water flow for 137 samples was 29.48 mL/min. The flow speeds obtained were 42.38 mL/min for turbines with one coolant aperture; 34.31 mL/min for turbines with two coolant apertures; and 30.44 mL/min for turbines with three coolant apertures. There were statistical differences between turbines with one and three coolant apertures (Tukey-Kramer multiple comparisons test with P < .05). Conclusion: Turbine handpieces with one cooling aperture distributed more water for the burs than high-speed handpieces with more than one aperture.

Detection of highways in high resolution images using Mathematical Morphology techniques

This paper seeks to apply a routine for highways detection through the mathematical morphology tools in high resolution image. The Mathematical Morphology theory consists of describing structures geometric presents quantitatively in the image (targets or features). This explains the use of the Mathematical Morphology in this work. As high resolution images will be used, the largest difficulty in the highways detection process is the presence of trees and automobiles in the borders tracks. Like this, for the obtaining of good results through the use of morphologic tools was necessary to choose the structuring element appropriately to be used in the functions. Through the appropriate choice of the morphologic operators and structuring elements it was possible to detect the highways tracks. The linear feature detection using mathematical morphology techniques, can contribute in cartographic applications, as cartographic products updating.

Search for neutral higgs bosons in Multi-b-Jet events in pp̄ collisions at s=1.96TeV

Data recorded by the D0 experiment at the Fermilab Tevatron Collider are analyzed to search for neutral Higgs bosons produced in association with b quarks. This production mode can be enhanced in the minimal supersymmetric standard model (MSSM). The search is performed in the three b quark channel using multijet triggered events corresponding to an integrated luminosity of 1fb-1. No statistically significant excess of events with respect to the predicted background is observed and limits are set in the MSSM parameter space. © 2008 The American Physical Society.

Microeconomic behavior in high uncertainty environments: the case of Argentina

Includes bibliography

The use of current transformers for noise detection due to sparking in insulators strings in high voltage transmission lines

In a general way, in an electric power utility the current transformers (CT) are used to measurement and protection of transmission lines (TL) 1 The Power Line Carriers systems (PLC) are used for communication between electrical substations and transmission line protection. However, with the increasing use of optical fiber to communication (due mainly to its high data transmission rate and low signal-noise relation) this application loses potentiality. Therefore, other functions must be defined to equipments that are still in using, one of them is detecting faults (short-circuits) and transmission lines insulator strings damages 2. The purpose of this paper is to verify the possibility of using the path to the ground offered by the CTs instead of capacitive couplings / capacitive potential transformers to detect damaged insulators, since the current transformers are always present in all transmission lines (TL's) bays. To this a comparison between this new proposal and the PLC previous proposed system 2 is shown, evaluating the economical and technical points of view. ©2010 IEEE.

Methodology for DSC calibration in high heating rates

Despite the large use of differential scanning calorimetry (DSC) technique in advanced polymer materials characterization, the new methodology called DSC in high heating rates was developed. The heating rate during conventional DSC experiments varying from 10 to 20°C.min-1, sample mass from 10 to 15mg and standard aluminum sample pan weighting, approximately, 27mg. In order to contribute to a better comprehension of DSC behavior in different heating rates, this work correlates as high heating rate influences to the thermal events in DSC experiments. Samples of metallic standard (In, Pb, Sn and Zn) with masses varying from 0.570mg to 20.9mg were analyzed in multiples sample heating rate from 4 to 324°C. min-1. In order to make properly all those experiments, a precise and careful temperature and enthalpy calibrations were performed and deeply discussed. Thus, this work shows a DSC methodology able to generate good and reliable results on experiments under any researcher choice heating rates to characterize the advanced materials used, for example, for aerospace industry. Also it helps the DSC users to find in their available instruments, already installed, a better and more accurate DSC test results, improving in just one shot the analysis sensitivity and resolution. Polypropylene melting and enthalpy thermal events are also studied using both the conventional DSC method and high heating rate method.

Import substitution in high-tech industries: Prebisch lives in Asia!

Includes bibliography

Informe del Seminario Regional sobre Políticas Agrarias y Sobrevivencia Campesina en Ecosistemas de Altura = Report of the Regional Seminar on Agrarian Policies and Peasant Survival in High-Altitude Ecosystems

Conclusiones y recomendaciones del Seminario cuyo objetivo fue analizar los problemas del campesinado andino en ecosistemas de altura relacionados con la penetración del estilo de desarrollo predominante en Latinoamérica, resaltando los complejos influjos recíprocos entre la oferta ambiental de recursos, las particularidades de los distintos pisos ecológicos, las formas y sistemas de organización social, los cambios y tendencias de la situación ambiental, para recomendar políticas de desarrollo que sean opciones viables para resolver los problemas del campesino de esas áreas. Incluye lista de participantes y documentos presentados.

Report of the special task force on collaboration in agricultural research

Presenta recomendaciones para establecer un criterio de colaboracion entre las agencias que operan en la region en el ambito de la investigacion agricola.

Opportunities for regional collaboration in dealing with problems arising from the impact of new technologies in Caribbean countries

Analiza las necesidades de la colaboracion regional en los procesos de integracion de las nuevas tecnologias a las estrategias de desarrollo nacional y regional en el Caribe.

Mechanisms for collaboration in science and technology between CCST and CARICOM

Presenta las recomendaciones para evitar la duplicacion de esfuerzos en la implementacion y fortalecimiento de la colaboracion en ciencia y tecnologia entre las agencias especializadas y los proyectos que deberian llevarse a cabo ya que el resultado de ellos puede ser la base para una mayor colaboracion entre los paises miembros del CCCT.

Proyecto Propuestas para la Transformación Productiva de la Vivienda en América Latina y el Caribe: marco conceptual y metodología general = Project Proposals for Changing Production Patterns in the Housing Sector in Latin America and the Caribbean: conceptual framework and general methodology

Incluye Bibliografía

Review of the economics of climate change (RECC) in the Caribbean project: Phase I climate change profiles in select Caribbean countries

These reports are the result of consultations which were conducted in 2008 in Aruba, Barbados, Netherlands Antilles, Dominican Republic, Guyana, Jamaica, Montserrat, Saint Lucia and Trinidad and Tobago. The objective was to obtain relevant information that would inform a Stern-type report where the economics of climate change would be examined for the Caribbean subregion. These reports will be complimented by future assessments of the costs of the “business as usual”, adaptation and mitigation responses to the potential impacts of climate change. It is anticipated that the information contained in each country report would provide a detailed account of the environmental profile and would, therefore, provide an easy point of reference for policymakers in adapting existing policy or in formulating new ones. ECLAC continues to be available to the CDCC countries to provide technical support in the area of sustainable development.

Transmission rate variation among three B chromosome variants in the fish Prochilodus lineatus (Characiformes, Prochilodontidae)

Estudos citogenéticos foram desenvolvidos em Prochilodus lineatus (Valenciennes 1836), os quais descrevem um interessante sistema de pequenos cromossomos supranumerários. O objetivo deste trabalho foi estudar a frequência e morfologia dos cromossomos B em indivíduos a partir da linhagem parental e os padrões de herança destes elementos em indivíduos obtidos a partir de cruzamentos controlados na espécie P. lineatus. A taxa de transmissão dos cromossomos B revelaram um kB=0,388 para o tipo acrocêntrico, kB=0,507 para o tipo metacêntrico e kB=0,526 submetacêntrico. Os resultados obtidos levantam hipóteses de que os cromossomos B do tipo acrocêntrico se encontram em fase de extinção, enquanto que os supranumerários do tipo metacêntrico e submetacêntrico encontram-se em fase de neutralização, seguindo uma taxa de transmissão Mendeliana.