Estudio comparativo in vitro de la microfiltración marginal de cavidades clase V restauradas con resina compuesta y cemento de vidrio ionómero modificado con resina.

Tesis para optar al Título de Cirujano DentistaRESUMEN Los materiales restauradores a lo largo del tiempo han buscado mejorar la unión de la interfase diente restauración. Uno de los grandes grupos son las resinas compuestas y los cementos de vidrio ionómero. El objetivo principal de este estudio es comparar el sellado marginal en restauraciones clase V obturadas con cemento de vidrio ionómero modificado con resina (Vitremer™) y resina compuesta Filtex ™Z 250. La muestra de este estudio experimental in vitro correspondió a 30 premolares a los que se les realizo cavidades estandarizadas clase V de 4mm de profundidad ,largo y ancho tanto por la cara vestibular y palatina. Las 30 cavidades vestibulares Se obturaron con cemento de vidrio ionómero modificado con resina (Vitremer™) y las 30 cavidades palatinas se obturaron con resina compuesta Filtex ™Z 250 , los dientes se sometieron a un proceso de baño termorregulador que consto de 3 recipientes con temperaturas de 55°,37° y 5° respectivamente en el que se sumergieron las 30 muestras por 20 segundos con un intervalo de 5 segundos por cada recipiente , luego se sumergieron en un recipiente con azul de metileno al 2% durante 24 horas para poder ver el nivel de penetración del pigmento en el diente , luego las muestras se cortaron en sentido vestíbulo palatino pasando por el centro de las restauraciones . Para poder medir la microfiltración se les asigno valores a los niveles de tinción siendo estos, 0: no penetro pigmento en la restauración, 1: penetración del pigmento solo en esmalte, 2: penetración del pigmento hasta dentina, 3: penetración del pigmento hasta la pared axio pulpar. Los niveles de tinción se observaron con aumento lupa de 2X, el resultado de los niveles de microfiltración se compararon con el método CHI cuadrado para realizar su análisis estadístico. Se observó que existía mayor nivel de penetración del pigmento en las cavidades obturadas con resina compuesta Filtex™ Z 250, encontrando diferencias significativas respecto a las cavidades obturadas con Vitremer ™, el cemento de vidrio ionómero mostro su mayor porcentaje de tinción solo en esmalte , con 56,6 % de las muestras , mientras que el mayor porcentaje de tinción para la resina compuesta fue hasta la dentina con un 60%, por lo que se puede concluir que el cemento de vidrio ionómero modificado con resina presenta menores niveles de microfiltración marginal y mejores niveles de adhesión a el tejido dentinario. Esto permite que una menor cantidad de sustancias nocivas penetren hasta la cámara pulpar del diente dando mejor pronóstico a la pieza dentaria restaurada. Palabras claves: vidrio ionómero, resina compuesta, microfiltración marginal Palabras claves: vidrio ionómero, resina compuesta, microfiltración marginal. ABSTRACT Over the time restoration materials have sought to improve the bonding of the tooth restoration interface.One of the bigger groups are the composit resin and glass ionomer cement. The principal objective of this study is to compare the marginal seal of class V restorations sealed with resin improved ionomer glass (Vitremer™) and Filtex™Z250 resin. The sample of this in vitro experimental study corresponded to 30 premolars that were cavitated with 4 mm deep and wide standardized class V cavities in the vestibular and palatine face. Universidad Andrés Bello, Facultad de odontología 2014. The 30 vestibular cavities were sealed with resin improved ionomer glass (Vitremer™) and the 30 palatine cavities were sealed with composite resin (Filtex™ Z250).the teeth were subjected to a thermoregulatory bath process with 3 temperatures containers: 55°, 37° and 5°C in which the samples were immersed for 20 seconds with a 5 seconds interval per container, then they were immersed in a 2% metilen blue container during 24 hours to see the pigment penetration level on the teeth, the samples were cuted in vestibular palatin direction through the restoration center. To measure the microfintrations were asigned values to the staining levels, beign these: 0: restoration wasnt penetrated by the pigment, 1: just enamel was penetrated by the pigment, 2: pigment penétrate throug dentine, 3:pigment penetrate to the axio-pulpar wall. The staining levels were observed with 2X magnification loupe, the microfiltraiting levels results were compared with the chi square method for the statistical analysis. It was observed that exist a higger penetration level of the pigment in the Filtex ™ Z250 sealed cavities, finding significative differences with the cavities sealed with Vitremer™ , the ionomer glass showed his highest staining percentage just on enamel with a 56,6% of the samples, while the highest staining percentage for the composite was 60% on dentine, so it can be concluded that ionomer glass has better levels of adherence to the dentinal tissue. That allows a smaller amount of harmful substances from penetrating to the pulp chamber of the tooth leading to better prognosis to the sealed tooth. Keywords: glass ionomer , composite resin, marginal microleakag

Ontology-driven International Maize Information System (IMIS) for Phenotypic and Genotypic Data Exchange

The Consultative Group on International Agricultural Research (CGIAR; http://www.cgiar.org/) centres have developed the International Crop Information System (ICIS; http://www.icis.cgiar.org) for the management and integration of global information on genetic resources, and germplasm improvement for any crop. The Maize breeding programs at CIMMYT (http://beta.cimmyt.org/) have different software tools to manage phenotypic, genotypic, and environmental information for their experiments generated worldwide. These tools have the capacity of collecting information in the field, wet lab, and store it into different relational databases. The IMIS (http://imis.cimmyt.org/confluence/display/IMIS/Crop+Finder) is an implementation of the ICIS, which is a computerized database system for general, integrated management and utilization of genealogy, nomenclature, genetic, phenotypic and characterization data for maize. Data exchange within and between databases as well as retrieving information are often hampered by the variability of terms used to describe comparable objects. To overcome this problem, the Crop Ontology (CO) database (http://cropontology.org/) is developed. It provides controlled vocabulary sets for several economically important plant species and facilitates biocurators working in genebanks of plant genetic resources (PGR) and crop breeding data curation and annotation. The maize trait ontology is developed as one of subclasses of CO trait ontology providing standardized trait descriptions, scales and scale values implemented into the IMIS. This ontology-driven IMIS will allow researchers who wish to exploit comparative phenotypic and genotypic information of maize to elucidate functional aspects of each trait

Sunday Friends: The Working Alternative to Charity

Sunday Friends is a non-profit organization in San José, California, that provides multiple activities for families who are in need of financial support. Given the particular location of the program, most families are Latino and bilingual. Participants and program volunteers form a community at an elementary school on a couple of scheduled Sundays each month. When family members participate in activities designed to educate, improve skills, and to give back to the larger community, they earn tickets that they can redeem for items that they need and want from the Sunday Friends store. Activities include healthy cooking projects, “Thank You Letter” writing, English-as-a-Second-Language programs, crafts, and education in nutrition and financial literacy. The program’s central focus is to empower families to break out of poverty. A specific guiding principal is the developmental assets approach promoted by the Search Institute in Minneapolis (http://www.search-institute.org/). This approach encourages individuals and organizations to work together toward a common goal of supporting the healthy development of all children and youth. Healthy development is conceptualized as consisting of the development of external assets (i.e., support, empowerment, boundaries and expectations, constructive activities) and internal assets (i.e., commitment to learning, positive values, social competencies, and positive identity). The 2009 evaluation’s primary focus was on whether Sunday Friends was succeeding at fostering developmental assets for children. Other relevant indicators of success were perceptions of program effectiveness, regard for program activities, and nutrition and healthy eating habits. Data were gathered from family members (adults and minors) during program activities using written surveys administered by volunteers to the research team (most of whom were bilingual). The families were recruited in person by program staff onsite. The questionnaires were written in English and Spanish (with the choice made by respondents). Sunday Friends volunteers were recruited to the study via email by Sunday Friends staff. They completed questionnaires through an online survey platform. In all, 74 parents or guardians, 67 children or youth, and 45 volunteers participated in the data collection. Across the three sets of surveys (parents or guardians, children or youth, and volunteers), there are fairly consistent results. The families and volunteers in the Sunday Friends program believe that Sunday Friends is effectively engaging them and meeting its goals. Overall, children and youth report positive experiences at Sunday Friends. On every dimension of psychological well-being, connectedness with others, and self-efficacy, the answers provided by children and youth indicate that Sunday Friends is promoting developmental assets. In addition, parents and guardians report that Sunday Friends has positive influences on their lives. The majority of measures, whether questions about self-efficacy, the effect of Sunday Friends on their children, or improved nutrition for their family, indicate that Sunday Friends is meeting its goals. Finally, volunteers agree that the program makes an important contribution to the lives of both children and adults. They also feel that Sunday Friends enhances their awareness of the community and contributes to making their personal lives more meaningful. The survey results presented here should be interpreted with caution because all persons surveyed were continuing participants in the program, and the cross-sectional data could not detect changes over time. Despite this caution, each group’s data and triangulation across family and volunteer surveys reveal that milestones are accomplished at Sunday Friends. It is safe to conclude that Sunday Friends’ community-based approach to empowering parents and youths is achieving its goals

Comment on “Bilaterian Burrows and Grazing Behavior at >585 Million Years Ago”

Pecoits et al. (Reports, 29 June 2012, p. 1693) describe bilaterian trace fossils and assign them an Ediacaran age based on the age of a granite interpreted as intrusive. We argue that the granite is not intrusive but in fact represents the basement of the sedimentary succession. Moreover, we show that identical trace fossils occur in nearby Carboniferous-Permian glacigenic rocks.Fil: Gaucher, Claudio. Universidad de la República; UruguayFil: Poire, Daniel Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: Bossi, Jorge. Universidad de la República; UruguayFil: Bettucci Sanchez, Leda. Universidad de la República; UruguayFil: Beri, Angeles. Universidad de la República; Urugua

Agri-Food Traceability Management using a RFID System with Privacy Protection

In this paper an agri-food traceability system based on public key cryptography and Radio Frequency Identification (RFID) technology is proposed. In order to guarantee safety in food, an efficient tracking and tracing system is required. RFID devices allow recording all useful information for traceability directly on the commodity. The security issues are discussed and two different methods based on public cryptography are proposed and evaluated. The first algorithm uses a nested RSA based structure to improve security, while the second also provides authenticity of data. An experimental analysis demonstrated that the proposed system is well suitable on PDAs to

Returning to the homeland: The migratory patterns between Brazil and Japan for Japanese-Brazilians

Migration to well-off countries has been well documented. However, the reasons why migrants return to their home countries, which often face severe economic disadvantages, are examined less frequently. The return migration of Japanese-Brazilians (Brazilian citizens of ethnic Japanese descent) who migrate to Japan and return again to Brazil has not been studied to any great extent. To understand the factors associated with Japanese-Brazilians’ return migration, using Gmelch\u27s (1983) model of push and pull factors, we examined what motivated Japanese-Brazilian migrant laborers to return to Brazil from Japan. With a mixed method including in-person interviews, a total of n=47 Brazilian migrants to Japan were sampled in São Paulo, Brazil. The present examination resulted in a pattern similar to the one Gmelch (1983) observed in his study on Irish and Newfoundlander return migrants. In the current study, pull factors were more important than push factors in terms of repatriation. Personal and social pull factors were stronger reasons compelling migrants return to Brazil than were economic or familial factors. Nevertheless, familial and economic reasons were also reported as important motivators for returning to Brazil in our interviews. Limitations are also discussed

Sobre el veraneo porteño, el desagüe de la bañadera y la meteorología

Cada vez que paseo por la Costanera, esencialmente durante el verano, no puedo evitar comparar la barrosa margen derecha del Río de la Plata con las doradas playas al otro lado del charco. Envidio a los montevideanos por tener templadas playas a pocos minutos de su lugar de trabajo o estudio.</p

Seamless Evaluation of Stochastic Physics Parametrizations

A substantial segment of the error in numerical weather prediction and climate projections comes from the intrinsic uncertainties of General Circulation Models of the atmosphere. Stochastic physics schemes are one of the preferred methods to represent the model uncertainty in Ensemble Prediction Systems, where different realizations of the same forecast are created to quantify the probabilities of different outcomes in the atmospheric flow. Stochastic physics schemes have been successfully employed in medium-range and seasonal forecasting systems, as they increase the skill of probabilistic forecasts. Similarly it has been demonstrated than these schemes can improve certain aspects of the model's climate. However, it is still not clear whether they are a truthful representation of the model uncertainties they aim to represent. In this thesis, a collection of stochastic physics schemes are evaluated using a seamless approach. It is found that they can improve the representation of the tropical climate and extra-tropical cyclones, but they degrade the individual representation of these processes deteriorating the deterministic skill of the model. Some important features of the model can be degraded by the stochastic physics schemes, like energy and moisture conservation on climate scales. Some closures to the schemes are proposed and successfully tested to remove or reduce some of the problems found. Alternative approaches in the development of stochastic parametrizations are also investigated. Stochastic physics schemes have some benefits but still require further development to produce a realistic representation of model error. It is also recommended that evaluation methodologies must be expanded to include process-based diagnostics to display the realism of its perturbations