10,077 research outputs found
Fiber-reinforced Composite for Chairside Replacement of Anterior Teeth: A Case Report
A variety of therapeutic modalities, from implant to conventional Maryland prosthesis, can be used for the replacement of a missing anterior tooth. Whenever a minimal tooth reduction is preferred, a fiber reinforced composite (FRC) prosthesis could be a good alternative to conventional prosthetic techniques, chiefly as temporary restoration before making a final decision on the treatment. The purpose of this case report is to describe the clinical procedure of fabricating anterior chairside FRC prosthesis with pre-impregnated unidirectional E-glass fibers and veneered particulate filler composite. Fiber-reinforced composite in combination with adhesive technology appears to be a promising treatment option for replacing missing teeth. However, further and long-term clinical investigation will be required to provide additional information on the survival of directly-bonded anterior fixed prosthesis made with FRC systems
Stability assessment of a tailings storage facility using a non-local constitutive model accounting for anisotropic strain-softening
Recent failures of upstream-raised tailings storage facilities (TSF) raised
con-cerns on the future use of these dams. While being cost-effective, they
entail higher risks than conventional dams, as stability largely relies on the
strength of tailings, which are loose and normally-consolidated materials that
may exhibit strain-softening during un-drained loading. Current design practice
involves limit equilibrium analyses adopting a fully-softened shear strength;
while being conservative, this practice neglects the work input required to
start the softening process that leads to progressive failure. This paper
describes the calibration and application of the NGI-ADPSoft constitutive model
to evaluate the potential of static liquefaction of an upstream-raised TSF and
provides an indirect measure of resilience. The constitutive model incorporates
undrained shear strength anisotropy and a mesh-independent anisotropic
post-peak strain softening. The calibration is performed using laboratory
testing, including anisotropically-consolidated triaxial compression tests and
direct simple shear tests. The peak and residual undrained shear strengths are
validated by statistical interpretation of the available CPTu data. It is shown
that this numerical exercise is useful to verify the robustness of the TSF
design.Comment: NGI-ADPSoft, Plaxis 2D, Strain-softening, Tailings, Static
Liquefactio
A new approach to cure and reinforce cold-cured acrylics
Purpose: The low degree of polymerization of cold-cured acrylics has resulted in inferior mechanical properties and fracture vulnerability in orthodontics removable appliances. Methods: In this study, the effect of reinforcement by various concentrations of chopped E-glass fibers (0%, 1%, 2%, 3% and 5% by weight of resin powder) and post-curing microwave irradiation (800 W for 3 min) on the flexural strength of cold-cured acrylics was evaluated at various storage conditions (at room temperature for 1 day and 7 days; at water storage for 7, 14 and 30 days). Results: The data was analyzed by using 1-way and 2-way ANOVA, and a Tukey post hoc test (α = .05). The specimens with chopped E-glass fibers treated with post-curing microwave irradiation significantly increased the flexural strength of cold-cured PMMA. The optimal concentration might be 2% fibers under irradiation. Conclusions: The exhibited reinforcement effect lasted in a consistent trend for 14 days in water storage. A new fiber-acrylic mixing method was also developed. © 2012 The Author(s).published_or_final_versio
Accessibility-based reranking in multimedia search engines
Traditional multimedia search engines retrieve results based mostly on the query submitted by the user, or using a log of previous searches to provide personalized results, while not considering the accessibility of the results for users with vision or other types of impairments. In this paper, a novel approach is presented which incorporates the accessibility of images for users with various vision impairments, such as color blindness, cataract and glaucoma, in order to rerank the results of an image search engine. The accessibility of individual images is measured through the use of vision simulation filters. Multi-objective optimization techniques utilizing the image accessibility scores are used to handle users with multiple vision impairments, while the impairment profile of a specific user is used to select one from the Pareto-optimal solutions. The proposed approach has been tested with two image datasets, using both simulated and real impaired users, and the results verify its applicability. Although the proposed method has been used for vision accessibility-based reranking, it can also be extended for other types of personalization context
Analysis of Voltage Regulator Module (VRM) Noise Coupling to High-Speed Signals with VRM Via Designs
The Physical Noise Coupling Mechanism between Voltage Regulator Module (VRM) Noise Coupling to High-Speed Signal Traces is Analyzed and Different Noise Reduction Methods Are Analyzed for the First Time. the Rapid Switching of Field Effect Transistors (FETs) Creates an Unintentional Coupling Region Around the VRM. as High-Speed Traces Are Often Routed in the Inner Signal Layers of Printed Circuit Boards (PCBs) as Striplines for Signal Integrity, the VRM Switching Noise is Mainly Coupled from Noisy Power Vias to the Victim Traces Routed Around the VRM Region. to Analyze Different Coupling Reduction Methods in Practical High-Speed Channels, a Simplified PCB Design based on a High-Speed Server Platform is Proposed. Case Studies under Various Conditions Verifies the Most Effective VRM Noise Coupling Reduction Method. Different Design Parameters that Influence the VRM Noise Coupling Are Analyzed to Provide a Design Guide for High-Speed Channel Designers
Higgsing M2 to D2 with gravity: N=6 chiral supergravity from topologically gauged ABJM theory
We present the higgsing of three-dimensional N=6 superconformal ABJM type
theories coupled to conformal supergravity, so called topologically gauged ABJM
theory, thus providing a gravitational extension of previous work on the
relation between N M2 and N D2-branes. The resulting N=6 supergravity theory
appears at a chiral point similar to that of three-dimensional chiral gravity
introduced recently by Li, Song and Strominger, but with the opposite sign for
the Ricci scalar term in the lagrangian. We identify the supersymmetry in the
broken phase as a particular linear combination of the supersymmetry and
special conformal supersymmetry in the original topologically gauged ABJM
theory. We also discuss the higgsing procedure in detail paying special
attention to the role played by the U(1) factors in the original ABJM model and
the U(1) introduced in the topological gauging.Comment: 53 pages, Late
Mathematical modeling of the metastatic process
Mathematical modeling in cancer has been growing in popularity and impact
since its inception in 1932. The first theoretical mathematical modeling in
cancer research was focused on understanding tumor growth laws and has grown to
include the competition between healthy and normal tissue, carcinogenesis,
therapy and metastasis. It is the latter topic, metastasis, on which we will
focus this short review, specifically discussing various computational and
mathematical models of different portions of the metastatic process, including:
the emergence of the metastatic phenotype, the timing and size distribution of
metastases, the factors that influence the dormancy of micrometastases and
patterns of spread from a given primary tumor.Comment: 24 pages, 6 figures, Revie
Visualization and measurement of the cell-free layer (CFL) in a microchannel network
In the past years, in vitro blood studies have revealed several significant hemodynamic phenomena that have played a key role in recent developments of biomedical microdevices for cells separation, sorting and analysis. However, the blood flow phenomena happening in complex geometries, such as microchannel networks, have not been fully understood. Thus, it is important to investigate in detail the blood flow behavior occurring at microchannel networks. In the present study, by using a high-speed video microscopy system, we have used two working fluids with different haematocrit (1% Hct and 15% Hct) and we have investigated the cell-free layer (CFL) in a microchannel network composed by asymmetric bifurcations. By using the Z Project method from the image analysis software ImageJ, it was possible to conclude that the successive bifurcations and confluences influence the formation of the CFL not only along the upper and lower wall of the microchannel but also at the region immediately downstream of the confluence apex.The authors acknowledge the financial support provided by the project POCI-01-0145 FEDER-016861 (with associated reference PTDC/QEQ-FTT/4287/2014), UID/EMS/00532/2013 and UID/CEC/00319/2013 funded by FCT (Foundation for Science and Technology), through national funds (PIDDAC), and FEDER through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI). D. Bento acknowledges the PhD scholarship SFRH/BD/91192/2012 granted by FCT.
The authors also acknowledge the financial support provided by the project Nos. UID/EMS/00532/2013 and UID/EMS/04077/2013 and the project Nos. UID/EMS/00532/2013,
UID/EMS/04077/2013, POCI-01-0145-FEDER-007043, UID/CEC/00319/2013info:eu-repo/semantics/publishedVersio
Primary Myeloid Sarcoma of the Ileum and Mesentery Causing Small Bowel Obstruction: Case Report and Literature Review
Myeloid sarcoma (extramedullary myeloblastoma, granulocytic sarcoma, chloroma) is an extramedullary isolated malignant tumor of myeloblasts and immature myelocytes. It can occur anywhere in the body as a solitary tumor or can be accompanied with acute myeloid leukemia. We are presenting a case of a young male patient that presented with sings of a small bowel obstruction and a palpable tumor mass in the abdomen. After uneventful postoperative period, the immunohistochemistry analysis reported an extramedullary myeloid sarcoma since a normal bone marrow biopsy was revealed
Saliva-based linezolid monitoring on a mobile UV spectrophotometer
Background: In TB, therapeutic drug monitoring (TDM) is recommended for linezolid; however, implementation is challenging in endemic settings. Non-invasive saliva sampling using a mobile assay would increase the feasibility of TDM. Objectives: To validate a linezolid saliva assay using a mobile UV spectrophotometer. Methods: The saliva assay was developed using NanoPhotometer NP80 (R) and linezolid concentrations were quantified using second-order derivative spectroscopy. Sample preparation involved liquid-liquid extraction of saliva, using saturated sodium chloride and ethyl acetate at 1:1:3 (v/v/v). The assay was validated for accuracy, precision, selectivity, specificity, carry-over, matrix effect, stability and filters. Acceptance criteria were bias and coefficient of variation (CV) Results: Linezolid concentrations correlated with the amplitude between 250 and 270 nm on the second-order derivative spectra. The linezolid calibration curve was Linear over the range of 3.0 to 25 mg/L (R-2 = 0.99) and the LLOQ was 3.0 mg/L. Accuracy and precision were demonstrated with bias of -7.5% to 2.7% and CV Conclusions: We validated a UV spectrophotometric assay using non-invasive saliva sampling for linezolid. The next step is to demonstrate clinical feasibility and value to facilitate programmatic implementation of TDM
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