361 research outputs found
In vitro evaluation of carrier based obturation technique: a CBCT study
AIM:
The goal of the study was to compare the ability of two different carrier based obturation (CBO) techniques to reach working length and fill in three-dimensions root canal systems, by using CBCT.
MATERIALS AND METHODS:
Twenty-six extracted molars were scanned with CBCT and 40 curved canals were selected (between 30° and 90°) and divided in two similar groups (n=20). All canals were prepared up to size 25 taper .06 using nickel-titanium instrumentation. The canals in the Group SC were obturated using Soft-Core obturators (Kerr, Romulus, Mi, USA), while Group TH canals (n= 20) were obturated using Thermafil Endodontic Obturators (Tulsa Dental Products, Tulsa, OK, USA), strictly following manufacturers' instructions for use. The obturations were analyzed by means of CBCT to measure the distance from the apical limit of obturation to the apical foramen and the presence of voids inside root canals.
RESULTS:
There was no significant difference between the two groups in the mean distance of the apical extent of the obturation (t test, p>0.05). Overfilling occurred in only 3 cases (2 in Group TH and 1 in Group SC). The percentages of voids in both groups were very low with no significant difference (Z test, p>0.05).
CONCLUSIONS:
The two tested CBO techniques showed similar positive results in terms of performance, even if, after checking with verifiers, in most cases the size of the selected Soft-Core obturator was one size smaller than Thermafil
Dynamic Penetration Profile of Starch Betainate, Pluronics and PCC Coated Papers
Despite changes in optical and printing properties, the applied coating components on the paper surface have a significant impact on the surface chemistry of office paper. Depending on the use, such as ink penetration for printing and writing papers, an optimal hydrophobic and hydrophilic balance may be beneficial. In this study, several coating components including starch betainate, Pluronics, and precipitated calcium carbonate were employed to coat base paper (paper without any surface treatment). The influence of these components on water penetration was investigated using dynamic penetration. When compared to native starch coated papers, paper coated with starch betainate (a cationic starch ester) showed reduction in hydrophobicity and increased water penetration. Moreover, this effect was further enhanced with the use of Pluronics. Likewise, hydrophobicity decreased as the concentration of starch betainate, precipitated calcium carbonate and Pluronics increased. Furthermore, water penetrated even more quickly when the combination of these components compared with the individual component coatings.
Keywords: hydrophobicity, PCC, Pluronics, starch betainate, water penetratio
Mine Closure in Iberoamerica (Module V, Economy and Finances)
Dina Franceschi is a contributing author, Improving Environmental Compliance in Mine Closure: The Case for a System of Performance Bonds , p. 207-218.
Book description: This book brings to the interested public the discussions and propositions delivered during the First Iberoamerican Seminar on Mine Closure held in La Rabida, at the monastery where Colon lived upon his return to Spain, after reaching the American Continent.-- Foreword.https://digitalcommons.fairfield.edu/economics-books/1005/thumbnail.jp
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Biosafety Practices and Emergency Response at the Idaho National Laboratory and Los Alamos National Laboratory
Strict federal regulations govern the possession, use, and transfer of pathogens and toxins with potential to cause harm to the public, either through accidental or deliberate means. Laboratories registered through either the Centers for Disease Control and Prevention (CDC), the U.S. Dept. of Agriculture (USDA), or both, must prepare biosafety, security, and incident response plans, conduct drills or exercises on an annual basis, and update plans accordingly. At the Idaho National Laboratory (INL), biosafety, laboratory, and emergency management staff have been working together for 2 years to satisfy federal and DOE/NNSA requirements. This has been done through the establishment of plans, training, tabletop and walk-through exercises and drills, and coordination with local and regional emergency response personnel. Responding to the release of infectious agents or toxins is challenging, but through familiarization with the nature of the hazardous biological substances or organisms, and integration with laboratory-wide emergency response procedures, credible scenarios are being used to evaluate our ability to protect workers, the public, and the environment from agents we must work with to provide for national biodefense
Producción de biomasa y respuesta a la fertilización de especies forrajeras subtropicales cultivadas en La Pampa deprimida bonaerense
La producción estival de biomasa forrajera de La Pampa deprimida bonaerense resulta muchas veces deficitaria para la alimentación del ganado. Una alternativa para incrementarla es cultivar especies perennes de origen subtropical. Algunas de estas especies, además de producir cantidades importantes de biomasa, han mostrado buena adaptación a condiciones ambientales similares a las de esta área. A pesar de tratarse de especies perennes, los estudios realizados hasta ahora en la zona generalmente abarcan solo los dos primeros años de crecimiento del cultivo. Por lo tanto, los objetivos de este estudio fueron evaluar: i) la productividad de especies forrajeras perennes subtropicales en comparación con la del pastizal natural por un periodo de 5 años desde la implantación del cultivo y ii) evaluar el efecto de la fertilización nitrogenada sobre la producción de biomasa de las especies subtropicales en la zona. Las especies estudiadas fueron Panicum coloratum cv. Klein Verde; Chloris gayana cvs. Finecut y Topcut y Setaria sphacelata cv. Narok. El experimento se condujo en la localidad de Verónica (Punta Indio, Bs. As.), perteneciente a la región de La Pampa deprimida bonaerense. La producción de biomasa seca aérea (BSA) de las especies subtropicales superó la del pastizal natural, comparando igual periodo de crecimiento. La fertilización nitrogenada incrementó la producción de BSA. Hasta el tercer ciclo de crecimiento hubo una buena recuperación de las plantas luego de los periodos invernales. Sin embargo, los cultivos de C. gayana y S. sphacelata no rebrotaron durante la primavera del cuarto ciclo de crecimiento. En cambio, P. coloratum continúa en producción luego de 5 años de la implantación del cultivo. Los datos obtenidos destacan que: i) las especies subtropicales incrementaron la productividad estival con relación al pastizal natural en La Pampa deprimida bonaerense, ii) la fertilización nitrogenada es una herramienta útil para incrementar la producción de biomasa y iii) es necesario incrementar el conocimiento sobre los factores que afectan la perennidad de las especies subtropicales en esta zona.Summer forage biomass production of Buenos Aires flooding Pampa is often deficient for livestock feeding. An alternative to increase it is the culture of subtropical perennial species. Some of them produce large amounts of biomass, and have also shown good adaptation to environmental conditions similar to that of the area. Despite being perennial species, studies performed so far in the area generally cover only the first two years of crop growth. Therefore, the objectives of this study were: i) to evaluate the productivity of subtropical perennial forage-species compared to that of the natural grassland during five years after crop implantation and ii) to evaluate the effect of nitrogen fertilization on the biomass production of the subtropical species in the area. The evaluated species were Panicum coloratum cv. Klein Verde; Chloris gayana cvs. Finecut and Topcut and Setaria sphacelata cv. Narok. The experiment was conducted in Veronica (Punta Indio, Buenos Aires), which belongs to the region of Buenos Aires flooding Pampa. Dry aerial biomass (DAB) of the subtropical species exceeded that of the natural grassland, during the same period of growth. Nitrogen fertilization increased aerial dry biomass production. Until the third growth cycle, there was a good recovery of the plants after winter periods. However, C. gayana and S. sphacelata did not resume growth during the spring of the fourth growth cycle. Instead, P. coloratum continues in production five years after the implantation. The data highlighted that: i) subtropical species produced more than the natural grassland during summer in Buenos Aires flooding Pampa; ii) nitrogen fertilization is a useful tool to increase biomass production and iii) it is necessary to increase knowledge about factors affecting subtropical forage perpetuity in this region.Gerencia de Comunicación e Imagen InstitucionalFil: Pesqueira, Julieta. Universidad Nacional de Lomas de Zamora. Facultad de Ciencias Agrarias. Cátedra de Fisiología Vegetal; ArgentinaFil: Huarte, Héctor Roberto. Universidad Católica Argentina. Facultad de Ingeniería y Ciencias Agrarias. Cátedra de Producción y Utilización de Forrajes; ArgentinaFil: García, María Dina. Universidad Nacional de Lomas de Zamora. Facultad de Ciencias Agrarias. Cátedra de Fisiología Vegetal; Argentin
Reactive Oxygen Species in Emulated Martian Conditions and Their Effect on the Viability of the Unicellular Alga Scenedesmus dimorphus
Formation of oxygen-based free radicals from photochemical decomposition of hydrogen peroxide (H2O2) on Mars may be a key factor in the potential survival of terrestrial-like organisms on the red planet. Martian conditions that generate reactive oxygen species involve the decomposition of H2O2 at temperatures of around 278 K under relatively high doses of C-band ultraviolet radiation (UVC). This process is further amplified by the presence of iron oxides and perchlorates. Photosynthetic organisms exhibit a number of evolutionary traits that allow them to withstand both oxidative stress and UVC radiation. Here, we examine the effect of free radicals produced by the decomposition of H2O2 under emulated martian conditions on the viability of Scenedesmus dimorphus, a unicellular alga that is resistant to UVC radiation and varying levels of perchlorate and H2O2, both of which are present on Mars. Identification and quantification of free radicals formed under these conditions were performed with Electron Paramagnetic Resonance spectroscopy. These results were correlated with the viability of S. dimorphus, and the formation of oxygen-based free radicals and survival of the alga were found to be strongly dependent on the amount of H2O2 available. For H2O2 amounts close to those present in the rarefied martian environment, the products of these catalytic reactions did not have a significant effect on the algal population growth curve.Fil: Bagnato, Carolina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche | Comision Nacional de Energia Atomica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche.; ArgentinaFil: Nadal, Marcela. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche | Comision Nacional de Energia Atomica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche.; ArgentinaFil: Tobia, Dina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche | Comision Nacional de Energia Atomica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche.; ArgentinaFil: Raineri Andersen, Mariana. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche | Comision Nacional de Energia Atomica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche.; ArgentinaFil: Vasquez Mansilla, Marcelo. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche | Comision Nacional de Energia Atomica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche.; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigación y Aplicaciones No Nucleares. Gerencia de Física. Laboratorio de Resonancias Magnéticas; ArgentinaFil: Winkler, Elin Lilian. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche | Comision Nacional de Energia Atomica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche.; ArgentinaFil: Zysler, Roberto Daniel. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche | Comision Nacional de Energia Atomica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche.; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigación y Aplicaciones No Nucleares. Gerencia de Física. Laboratorio de Resonancias Magnéticas; ArgentinaFil: Lima, Enio Junior. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche | Comision Nacional de Energia Atomica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia. Unidad Ejecutora Instituto de Nanociencia y Nanotecnologia - Nodo Bariloche.; Argentin
The Last Mile in Analyzing Wellbeing and Poverty : Indices of Social Development
__Abstract__
Development practitioners worldwide increasingly recognize the importance of informal institutions - such as norms of cooperation, non-discrimination, or the role of community oversight in the management of investment activities – in affecting well-being, poverty, and even economic growth. There has been little empirical analysis that tests these relationships at the international level. This is largely due to data limitations: few reliable, globally-representative data sources exist that can provide a basis for cross-country comparison of social norms and practice, social trust and community engagement
EFEITOS DE ESTILO E DE HUMOR: PERSPECTIVA CONTRA-CANÔNICA DO DISCURSO ACADÊMICO
O discurso de Austin (1990), com orientações antianalíticas da Filosofia da Linguagem Ordinária, organiza-se pela problematização do humor e do estilo, marcado pela situação concreta de uso, o qual é dialogicamente responsivo. Definindo os conceitos de estilo, humor e responsividade, conforme Bakhtin (2015; 2011; 1978) e Volóchinov (2017), discutimos sobre a forma como Austin se desloca do cânone acadêmico. Destacamos a possibilidade de que a performance discursivo-teórico-conceitual desconstrutora austiniana é uma forma de problematizar os modus operandi conservadores que encarceram a produção científica e filosófica a procedimentos higienizados da linguagem ordinária
Inhalation therapy in the next decade : Determinants of adherence to treatment in asthma and COPD
Peer reviewedPublisher PD
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