Effect of reciprocating instrumentation on chlorhexidine substantivity on human dentin: chemical analysis followed by confocal laser microscopy

The present research analyzed the reciprocating instrumentation associated to chlorhexidine (CHX) substantivity as its correlation with E. faecalis viabilityin ex vivoroot canals. Eighty extracted single-rooted human teeth were used, being 40 to high-performance liquid chromatography (HPLC) and 40 to confocal laser scanning microscopy (CLSM). In both, teeth were decoronated and the cervical third was prepared. In the CLSM analysis, the root canals were inoculated with E. faecalisfor 14 days. Samples were divided into 4 groups (n=10) according to instrumentation technique: no instrumentation and irrigation with distilled water (control); manual instrumentation (K-File); rotary instrumentation (ProTaper Next); and reciprocating instrumentation (Reciproc R25). Two percent chlorhexidine was applied as irrigating substance in experimental groups. Longitudinal grooves resulted in 2 halves root and 20 proof bodies in each group. Samples were divided by chance in two groups (n=10) and theoutcomes were evaluated after two days and one week. The retained chlorhexidine and live cells after instrumentation techniques in each evaluation time was measured by HPLC and CLSM, respectively. Specific analysis was applied for experimental tests (p≤0.05). Both rotary as well as reciprocating techniques significantly reduced the amount of chlorhexidine on dentin in all observation periods (p0.05). Reciprocating instrumentation does not interfere on chlorhexidine substantivity

Acompanhamento da Safra 2012/2013 de Arroz Irrigado no Rio Grande do Sul por Modelagem Numérica

O objetivo deste trabalho foi realizar o acompanhamento de safra de arroz irrigado durante o ano agrícola 2012/2013 para o estado do Rio Grande do Sul. Para o acompanhamento de safra, foi utilizado o modelo SimulArroz. Foi utilizado o grupo de maturação precoce de cultivares de arroz, com simulações nos níveis de tecnologia alto, médio e baixo. A média de produtividade observada foi de 7481,7 kg/ha, enquanto que a média de produtividade simulada com o SimulArroz nos níveis de tecnologia alto, média e baixo foi de 8732,0 kg/ha, 7041,7 kg/ha e 5597,9 kg/ha respectivamente. O modelo demonstrou boa sensibilidade às variações meteorológicas entre as regiões do RS, demonstrando maior potencial produtivo de arroz para as regiões da Fronteira Oeste e da Campanha. Portanto, o modelo SimulArroz simulou de forma satisfatória a produtividade de arroz irrigado para os municípios em que foi testado, podendo ser utilizado no acompanhamento de safra

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements