AN INVERTIBLE TRANSFORMATION AND SOME OF ITS APPLICATIONS

Several applications of an explicitly invertible transformation are reported. This transformation is elementary and therefore all the results obtained via it might be considered trivial; yet the findings highlighted in this paper are generally far from appearing trivial until the way they are obtained is revealed. Various contexts are considered: algebraic and Diophantine equations, nonlinear Sturm–Liouville problems, dynamical systems (with continuous and with discrete time), nonlinear partial differential equations, analytical geometry, functional equations. While this transformation, in one or another context, is certainly known to many, it does not seem to be as universally known as it deserves to be, for instance it is not routinely taught in basic University courses (to the best of our knowledge). The main purpose of this paper is to bring about a change in this respect; but we also hope that some of the findings reported herein — and the multitude of analogous findings easily obtainable via this te..

Efeito do uso de forradores resinosos sobre a microinfiltração de restaurações classe V em compósito odontológico

OBJETIVO: O objetivo desse estudo foi avaliar os efeitos da aplicação de um adesivo em diferentes espessuras ou em associação com um adesivo com carga ou com compósito de baixa viscosidade na microinfiltração marginal de restaurações com compósito odontológico. MÉTODOS: Quarenta incisivos bovinos foram selecionados e cavidades circulares (4mm de diâmetro X 2mm de profundidade) foram preparadas na região da junção cemento-esmalte. Os dentes foram então divididos em quatro grupos de acordo com o forramento utilizado: 1: (controle) aplicação do sistema de união Scotchbond Multi Uso (SBMU) - 1 camada de adesivo; 2: aplicação de 3 camadas do adesivo SBMU; 3: aplicação do SBMU, seguido pela aplicação de uma camada do adesivo Optibond FL; 4: aplicação do SBMU seguido pela aplicação de forramento com o compósito de baixa viscosidade Flow-it. Todas as cavidades foram restauradas com o compósito Z100. O teste de microinfiltração foi conduzido de acordo com a ISO (TR11405). Os dados foram analisados pelo teste de Kruskall-Wallis (p>;0,05). RESULTADOS: O grupo 4 apresentou redução significativa dos níveis de infiltração quando comparado ao grupo 1. Os grupos 2 e 3 apresentaram valores intermediários e não foram detectadas diferenças significativas quando estes grupos foram comparados aos grupos 1 e 4. CONCLUSÃO: O uso de forramento com compósito de baixa viscosidade pode reduzir os níveis de infiltração marginal, possibilitando melhora na qualidade das restaurações em compósito odontológico.PURPOSE: The aim of this study was to evaluate the effect of an adhesive applied in layers of different thickness or in association with a filled adhesive or with a low viscosity composite liner on the microleakage of composite restorations. METHODS: Forty bovine incisors were prepared with round cavities (4mm diameter X 2mm depth) on the cementoenamel junction. The teeth were assigned to four groups according to the liner used: 1 (control) - application of 1 layer of the Scotchbond Multi Purpose adhesive system (SBMP); 2 - application of 3 layers of SBMP; 3 - application of 1 layer of SBMP followed by application of one layer of Optibond FL adhesive; 4 - application of one layer of SBMP followed by application of flowable composite Flow-it. All cavities were restored using composite resin Z100. The microleakage test was conducted according to ISO (TR11405). Data were analyzed by Kruskall-Wallis test (a=0.05). RESULTS: Group 4 showed less leakage than Group 1. Groups 2 and 3 showed intermediate values and there were no statistical differences when they were compared to the values of Groups 1 and 4 CONCLUSION: The use of resin liners with flowable composites can reduce the microleakage of composite restorations

Effect Of Resin Liners On The Microleakage Of Class V Dental Composite Restorations.

The aim of this study was to evaluate the effect of an adhesive applied in layers of different thickness or in association with a filled adhesive or with a low viscosity composite liner on the microleakage of composite restorations. Forty bovine incisors were prepared with round cavities (4mm diameter X 2mm depth) on the cementoenamel junction. The teeth were assigned to four groups according to the liner used: 1 (control) - application of 1 layer of the Scotchbond Multi Purpose adhesive system (SBMP); 2 - application of 3 layers of SBMP; 3 - application of 1 layer of SBMP followed by application of one layer of Optibond FL adhesive; 4 - application of one layer of SBMP followed by application of flowable composite Flow-it. All cavities were restored using composite resin Z100. The microleakage test was conducted according to ISO (TR11405). Data were analyzed by Kruskall-Wallis test (a=0.05). Group 4 showed less leakage than Group 1. Groups 2 and 3 showed intermediate values and there were no statistical differences when they were compared to the values of Groups 1 and 4 The use of resin liners with flowable composites can reduce the microleakage of composite restorations.1256-6

Anthropogenic geomorphic change as a potential generator of renewable geologic resources in the humid Pampa of Argentina

The nature and amount of sediments in various lakes, intermittent swampy areas and river sectors in the humid Pampa (Buenos Aires Province, Argentina) were analysed. The aim was to determine whether recent sediments in such environments could serve as an alternative resource to the brick industry, for minimising the current, high environmental impact of soil mining. Sediment sequences were obtained, and the thicknesses of the upper sediment layers, corresponding to the suballuvial (approx. 1400-700 years BP) and alluvial (approx. 250 years BP to present) were determined. Sediment samples were collected and analysed for grain size and Atterberg limits. Suitable sediments were then selected to determine the optimal brick materials and their technical properties. Similarly, control bricks were prepared with ceramic pastes of local industries. The results show that the quality of the former is similar or superior to that of the latter. The initial estimates of the available resource indicate a long-term supply for the industry. Estimates of the current sedimentation rates indicate that resource renewal might occur at a rate comparable to current consumption. The sedimentation rates have increased significantly in the past two centuries - more so in the past few decades (the Anthropocene?) - with increasing human modification of geomorphic processes. If the results presented here are confirmed, a highly sustainable model can be implemented in the brick industry.Facultad de Ciencias Naturales y Muse

Effect Of Photoinitiator Concentration On Marginal And Internal Adaptation Of Experimental Composite Blends Photocured By Modulated Methods.

The aim of this study was to evaluate the influence of photoinitiator concentration on marginal and internal adaptation of composites photocured by modulated methods. Composites based on BisGMA/triethylene glycol dimethacrylate and 65 wt% of filler were prepared with different concentrations of camphorquinone/amine (C1-0.5%, C2-1%, C3-1.5%). Cavities were prepared (3 mm × 3 mm × 2 mm) on the buccal surface of 120 bovine incisors and the adhesive system Adper Single Bond 2 was applied following manufactures instruction. Specimens were then distributed according to type of composite (C1, C2, C3) and photoactivation method (high-intensity - 750 mW/cm(2) for 40 s; low intensity - 150 mW/cm(2) for 200 s; soft-start - 150 mW/cm(2) for 10 s + 750 mW/cm(2) for 38 s; pulse-delay - 150 mW/cm(2) for 10 s + 3 min dark + 750 mW/cm(2) for 38 s). Superficial and internal margins were analyzed by scanning electron microscopy, using the epoxy replica technique. The length of gaps was expressed as a percentage of the total length of the margins. Data were submitted to two-way analysis of variance and Tukey's test (α =0.05). Modulated curing methods did not influence gap formation regarding both superficial and internal adaptation. The composite with the lower initiator concentration (C1) presented higher gap formation when compared with those with higher concentrations (C2 and C3). Modulated photoactivation methods did not reduce gap formation for the experimental composite restorations evaluated. However, higher photoinitiator concentrations promote better marginal seal.7S1-

Evidence of SARS-CoV-2 in nasal brushings and olfactory mucosa biopsies of COVID-19 patients

The aim of the present study is to detect the presence of SARS-CoV-2 of patients affected by COVID-19 in olfactory mucosa (OM), sampled with nasal brushing (NB) and biopsy, and to assess whether a non-invasive procedure, such as NB, might be used as a large-scale procedure for demonstrating SARS-CoV-2 presence in olfactory neuroepithelium. Nasal brushings obtained from all the COVID-19 patients resulted positive to SARS-CoV-2 immunocytochemistry while controls were negative. Double immunofluorescence showed that SARS-CoV-2 positive cells included supporting cells as well as olfactory neurons and basal cells. OM biopsies showed an uneven distribution of SARS-CoV-2 positivity along the olfactory neuroepithelium, while OM from controls were negative. SARS-CoV-2 was distinctively found in sustentacular cells, olfactory neurons, and basal cells, supporting what was observed in NB. Ultrastructural analysis of OM biopsies showed SARS-CoV-2 viral particles in the cytoplasm of sustentacular cells. This study shows the presence of SARS-CoV-2 at the level of the olfactory neuroepithelium in patients affected by COVID-19. For the first time, we used NB as a rapid non-invasive tool for assessing a potential neuroinvasion by SARS-CoV-2 infection

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

Space QUEST mission proposal: experimentally testing decoherence due to gravity

Models of quantum systems on curved space-times lack sufficient experimental verification. Some speculative theories suggest that quantum properties, such as entanglement, may exhibit entirely different behavior to purely classical systems. By measuring this effect or lack thereof, we can test the hypotheses behind several such models. For instance, as predicted by Ralph and coworkers [T C Ralph, G J Milburn, and T Downes, Phys. Rev. A, 79(2):22121, 2009, T C Ralph and J Pienaar, New Journal of Physics, 16(8):85008, 2014], a bipartite entangled system could decohere if each particle traversed through a different gravitational field gradient. We propose to study this effect in a ground to space uplink scenario. We extend the above theoretical predictions of Ralph and coworkers and discuss the scientific consequences of detecting/failing to detect the predicted gravitational decoherence. We present a detailed mission design of the European Space Agency's (ESA) Space QUEST (Space - Quantum Entanglement Space Test) mission, and study the feasibility of the mission schema.Comment: 18 pages, 13 figures, included radiation damage to detectors in appendi