Search results for "Root"
showing 10 items of 1237 documents
Interferometric microscopy study of the surface roughness of Portland cement under the action of different irrigants
2013
Objectives: Some investigations suggested common Portland cement (PC) as a substitute material for MTA for endodontic use; both MTA and PC have a similar composition. The aim of this study was to determine the surface roughness of common PC before and after the exposition to different endodontic irrigating solutions: 10% and 20% citric acid, 17% ethylenediaminetetraacetic (EDTA) and 5% sodium hypochlorite. Study Design: Fifty PC samples in the form of cubes were prepared. PC was mixed with distilled water (powder/liquid ratio 3:1 by weight). The samples were immersed for one minute in 10% and 20% citric acid, 17% EDTA and 5% sodium hypochlorite. After gold coating, PC samples were examined …
Treatment of multiple traumatized anterior teeth associated with an alveolar bone fracture in a 20-year-old patient: A 3-year follow up
2014
Intrusive luxation is a type of recognizable luxation injury represented by a deeper axial displacement of the tooth toward the alveolar bone. Treatment strategies include waiting for the tooth to return to its position, immediate surgical repositioning, and repositioning through dental traction by orthodontic devices. The aim of this case report was to present the management of severe dental trauma and later restoration following IADT. A 20-year-old patient was presented after fainting at home four hours before, resulting in a dento-alveolar trauma. Clinical examinations revealed a traumatic intrusion, in 1.2, 1.1 and 2.1, uncomplicated crown fractures in 1.1 and 2.1 and a complicated crow…
Treatment of Gingival Recession: When and How?
2021
Gingival recession is a common finding in daily clinical practice. Several issues may be associated with the apical shift of the gingival margin such as dentine hypersensitivity, root caries, non-carious cervical lesions (NCCLs), and compromised aesthetics. The first step in an effective management and prevention program is to identify susceptibility factors and modifiable conditions associated with gingival recession. Non-surgical treatment options for gingival recession defects include establishment of optimal plaque control, removal of overhanging subgingival restorations, behaviour change interventions, and use of desensitising agents. In cases where a surgical approach is indicated, co…
Mode of Delivery and the Effectiveness of Foreign Aid: The Example of Missionary Work
2010
Conventional development aid, typically a service from government to government, has been a relatively poor determinant of economic growth or human development in developing countries. In this paper we test whether a distinctly grass-roots delivery mode, as is the case with missionary work, leads to a more effective dispersion of foreign aid. In addition to its mode of delivery, missionary work is also of interest as there is a known positive correlation between the growth rate of Christianity and economic development. We estimate the economic growth impacts of development aid versus missionary work variables by using empirical data from 119 countries and discuss several explanations for ou…
Zagrożenie upraw kukurydzy szkodnikiem Diabrotica virgifera (w oparciu o monitoring prowadzony na obszarze wybranych gmin województwa opolskiego)
2018
Powiększający się z roku na rok areał kukurydzy w Polsce, stwarza idealne warunki do rozwoju wielu agrofagów. Do najgroźniejszych z nich należy zachodnia kukurydziana stonka korzeniowa Diabrotica virgifera Le Conte, która z powodu specyficznego sposobu żerowania powoduje bardzo duże straty plonu. Do 6 lutego 2014 roku stonka posiadała status organizmu kwarantannowego i inwazyjnego na terenie całej Unii Europejskiej, w tym także w Polsce. Ocenę zagrożenia upraw przez szkodnika, przeprowadzono w latach 2012-2013 na obszarze dwóch miejscowości Zopowy i Lubotyń (gminy Głubczyce i Kietrz), a następnie porównano je z badaniami monitoringowymi prowadzonymi przez Państwową Inspekcję Ochrony Roślin …
Innovative and Applied Research in Biology: Proceedings
2022
The collection contains SCIENTIFIC articles on the topics of the LU 80 conference reports. The main focus is on innovative and applied research in biology and interdisciplinary fields.
Accommodation in human eye models: a comparison between the optical designs of Navarro, Arizona and Liou-Brennan.
2017
Aim To simulate and compare accommodation in accommodative and non-accommodative human eye models. Methods Ray tracing and optical design program was used. Three eye models were designed and studied: the Navarro, the Arizona and the Liou-Brennan. In order to make the Navarro and Liou-Brennan models to accommodate, specific geometric parameters of the models were altered with values that were chosen from the literature. For the Arizona model, its' mathematical functions for accommodation were used for the same accommodative demands. The simulation included four distances of accommodation for each model: at infinity, 3, 1 and 0.5 m.The results were diffraction images of a "letter F" for graph…
Characterization of estuarine sediments by near infrared diffuse reflectance spectroscopy
2008
It has been developed a partial least squares near infrared (PLS-NIR) method for the determination of estuarine sediment physicochemical parameters. The method was based on the chemometric treatment of first order derivative reflectance spectra obtained from samples previously lyophilized and sieved through a lower than 63 μm grid. Spectra were scanned from 833 to 2976 nm, averaging 36 scans per spectrum at a resolution of 8 cm-1, using chromatographic glass vials of 9.5 mm internal diameter as measurement cells. Models were built using reference data of 31 samples selected through the use of a hierarchical cluster analysis of NIR spectra of sediments obtained from the Ria de Arousa estuary…
Root-restricted Kleenean rotations
2010
We generalize the Kleene theorem to the case where nonassociative products are used. For this purpose, we apply rotations restricted to the root of binary trees.
A General Algorithm to Calculate the Inverse Principal $p$-th Root of Symmetric Positive Definite Matrices
2019
We address the general mathematical problem of computing the inverse p-th root of a given matrix in an efficient way. A new method to construct iteration functions that allow calculating arbitrary p-th roots and their inverses of symmetric positive definite matrices is presented. We show that the order of convergence is at least quadratic and that adaptively adjusting a parameter q always leads to an even faster convergence. In this way, a better performance than with previously known iteration schemes is achieved. The efficiency of the iterative functions is demonstrated for various matrices with different densities, condition numbers and spectral radii.