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Imaging Science in Dentistry Jun 2024This study examined the influence of a metal artifact reduction (MAR) tool, sharpening filters, and their combination on the diagnosis of vertical root fracture (VRF) in...
PURPOSE
This study examined the influence of a metal artifact reduction (MAR) tool, sharpening filters, and their combination on the diagnosis of vertical root fracture (VRF) in teeth with metallic posts using cone-beam computed tomography (CBCT).
MATERIALS AND METHODS
Twenty single-rooted human premolars - 9 with VRF and 11 without - were individually placed in a human mandible. A metallic post composed of a cobalt-chromium alloy was inserted into the root canal of each tooth. CBCT scans were then acquired under the following parameters: 8 mA, a 5×5 cm field of view, a voxel size of 0.085 mm, 90 kVp, and with MAR either enabled or disabled. Five oral and maxillofacial radiologists independently evaluated the CBCT exams under each MAR mode and across 3 sharpening filter conditions: no filter, Sharpen 1×, and Sharpen 2×. The diagnostic performance was quantified by the area under the receiver operating characteristic curve (AUC), sensitivity, and specificity. These metrics were compared using 2-way analysis of variance with a significance level of α=5%. Intra- and inter-examiner agreement were assessed using the weighted kappa test.
RESULTS
Neither MAR nor the application of sharpening filters significantly impacted AUC or specificity (>0.05). However, sensitivity increased when MAR was combined with Sharpen 1× and Sharpen 2× (=0.015). The intra-examiner agreement ranged from fair to substantial (0.34-0.66), while the inter-examiner agreement ranged from fair to moderate (0.27-0.41).
CONCLUSION
MAR in conjunction with sharpening filters improved VRF detection; therefore, their combined use is recommended in cases of suspected VRF.
PubMed: 38948185
DOI: 10.5624/isd.20230233 -
RSC Advances Jun 2024A new eco-friendly method for creating an optical sensor membrane specifically designed to detect yttrium ions (Y) has been developed. The proposed sensor membrane is...
A new eco-friendly method for creating an optical sensor membrane specifically designed to detect yttrium ions (Y) has been developed. The proposed sensor membrane is fabricated by integrating 4-(2-arsonophenylazo) salicylic acid (APASA), sodium tetraphenylborate (Na-TPB), and tri--octyl phosphine oxide (TOPO) into a plasticized poly(vinyl chloride) matrix with dimethyl sebacate (DMS) as the plasticizer. In this sensor membrane, APASA functions dually as an ionophore and a chromoionophore, while TOPO enhances the complexation of Y ions with APASA. The composition of the sensor membrane has been meticulously optimized to achieve peak performance. The current membrane exhibits a linear dynamic range for Y ions from 8.0 × 10 to 2.3 × 10 M, with detection and quantification limits of 2.3 × 10 and 7.7 × 10 M, respectively. No interference from other potentially interfering cations and anions was observed in the determination of Y. The membrane showed strong stability and a swift response time of about 3.0 minutes, with no signs of APASA leaching. This sensor is highly selective for Y ions and can be renewed by treating it with 0.15 M HNO. It has been effectively applied to measure Y in nickel-based alloys, as well as in biological and environmental samples.
PubMed: 38946767
DOI: 10.1039/d4ra03854a -
Analytical Methods : Advancing Methods... Jul 2024High-frequency pulse lasers, applied in the form of rapid scanning, act upon the surface of aircraft skin paint layers, thereby removing the paint layers, exhibiting...
High-frequency pulse lasers, applied in the form of rapid scanning, act upon the surface of aircraft skin paint layers, thereby removing the paint layers, exhibiting characteristics of efficiency and eco-friendliness. Real-time monitoring of the paint removal effect and prevention of substrate damage necessitates the continuous monitoring of paint removal thickness. Combining Laser-Induced Breakdown Spectroscopy (LIBS) online monitoring technology enables laser-controlled paint removal under multiple effects coupling, meeting the requirements of airworthiness maintenance. This paper, based on a high-frequency nanosecond infrared pulse laser paint removal LIBS monitoring platform, conducts research on laser paint removal thickness LIBS online monitoring of aluminum alloy plates coated with dual-layer paint. Spectra corresponding to the removal thickness of each group are collected and, respectively, paint removal thickness monitoring models based on LIBS spectra are established using the standard curve method and Principal Component Analysis-Support Vector Regression (PCA-SVR) algorithm. When monitoring paint removal thickness using the standard curve method, the intensity of five Ti element characteristic spectral lines selected is correlated with the paint removal thickness, and segmented curve fitting according to the paint layer structure satisfies the segmented curve fitting of topcoat and topcoat + primer. Among them, the average coefficient of the curve fitting of the Ti II 589.088 nm characteristic spectral line is 0.89, and the root mean square error (RMSE) is 12.28 μm. Its performance is superior in the five standard curves; thus, its fitting equation is used as the criterion for paint removal thickness monitoring. To further improve monitoring accuracy, research on paint removal thickness monitoring models based on PCA-SVR is conducted. Compared to the traditional univariate standard curve method, the PCA-SVR model does not require segmented monitoring. After parameter optimization, the average fitting coefficient reaches 0.97, and the RMSE is 2.92 μm. The results indicate that the PCA-SVR-based paint removal thickness monitoring model has higher accuracy, thereby forming the basis for paint removal thickness monitoring. Through comparative research on paint removal thickness monitoring models, two types of paint removal thickness monitoring criteria are obtained, providing model solutions for high-precision monitoring and automation of aircraft skin laser paint removal thickness.
PubMed: 38946640
DOI: 10.1039/d4ay00872c -
Chemical Communications (Cambridge,... Jul 2024Designing electrocatalysts for seawater splitting remains challenging. A Ru-Co alloy supported by an N-doped carbon substrate catalyst has been designed using etching...
Designing electrocatalysts for seawater splitting remains challenging. A Ru-Co alloy supported by an N-doped carbon substrate catalyst has been designed using etching and a low-temperature treatment method. Studies show that the superior performance of this catalyst is related to the hollow-structured N-doped carbon frame and surface reconstruction of the Ru-Co alloy.
PubMed: 38946539
DOI: 10.1039/d4cc02081b -
ACS Applied Materials & Interfaces Jul 2024Antimony has a high theoretical capacity and suitable alloying/dealloying potentials to make it a future anode for potassium-ion batteries (PIBs); however, substantial...
Antimony has a high theoretical capacity and suitable alloying/dealloying potentials to make it a future anode for potassium-ion batteries (PIBs); however, substantial volumetric changes, severe pulverization, and active mass delamination from the Cu foil during potassiation/depotassiation need to be overcome. Herein, we present the use of electrophoretic deposition (EPD) to fabricate binder-free electrodes consisting of Sb nanoparticles (NPs) embedded in interconnected multiwalled carbon nanotubes (MWCNTs). The anode architecture allows volume changes to be accommodated and prevents Sb delamination within the binder-free electrodes. The Sb mass ratio of the Sb/CNT nanocomposites was varied, with the optimized Sb/CNT nanocomposite delivering a high reversible capacity of 341.30 mA h g (∼90% of the initial charge capacity) after 300 cycles at C/5 and 185.69 mA h g after 300 cycles at 1C. Postcycling investigations reveal that the stable performance is due to the unique Sb/CNT nanocomposite structure, which can be retained over extended cycling, protecting Sb NPs from volume changes and retaining the integrity of the electrode. Our findings not only suggest a facile fabrication method for high-performance alloy-based anodes in PIBs but also encourage the development of alloying-based anodes for next-generation PIBs.
PubMed: 38946438
DOI: 10.1021/acsami.4c02318 -
Journal of the Mechanical Behavior of... Jun 2024Developing new low modulus structures is important for reducing the risk of aseptic loosening during loading of implant materials. However, an alloy that may also confer...
Developing new low modulus structures is important for reducing the risk of aseptic loosening during loading of implant materials. However, an alloy that may also confer some advantage at preventing septic loosening could dramatically improve the outcomes for patients. Nevertheless, the predictive power of current models remains limited to common alloying additions. As such, this study considers the mechanical properties of a range of Ti-Nb-Au superelastic alloys to elucidate the composition range for which low modulus structures can be achieved. These modulus values are compared to other critical design parameters such as strain recovery and strength. It was found that Au additions are effective at suppressing the formation of the ω phase and allow alloys with lower moduli to be achieved. It was also shown that low β phase stability is critical for achieving the lowest modulus, and that this susceptibility to transform to a martensite may enable higher strengths to be achieved. However, this low β phase stability also limits the strain recovery that may be achieved meaning these two properties are not necessarily independently tuneable. These data provide important context for the design of new systems containing unusual alloying additions such as Au.
PubMed: 38943903
DOI: 10.1016/j.jmbbm.2024.106633 -
Advanced Materials (Deerfield Beach,... Jun 2024The safe service and wide applications of lightweight high-strength aluminum alloys are seriously challenged by diverse environmental corrosion, since high strength and...
Nature-Inspired Incorporation of Precipitants into High-Strength Bulk Aluminum Alloys Enables Life-Long Extraordinary Corrosion Resistance in Diverse Aqueous Environments.
The safe service and wide applications of lightweight high-strength aluminum alloys are seriously challenged by diverse environmental corrosion, since high strength and corrosion resistance are mutually exclusive for metals while surface protection cannot provide life-long corrosion resistance. Here, inspired by fish secreting slime from glands to resist external changes, a strategy of incorporating precipitants as the slime into bulk metals using the inner cavity of opened carbon nanotubes (CNTs) as the glands is developed to enable high-strength aluminum alloys with life-long superior corrosion resistance. The resulting material has ultrahigh tensile strength (∼700 MPa) and extraordinary corrosion resistance in acidic, neutral and alkaline media. Notably, it has the highest resistance to intergranular corrosion, exfoliation corrosion and stress-corrosion cracking, compared with all previously reported aluminum alloys, and its corrosion rate is even much lower than that of corrosion-resistant pure aluminum, which results from the pronounced surface enrichment of precipitants released (secreted) from exposed CNTs forming a protective surface film. Such high corrosion resistance is life-long and self-healing due to the on-demand minimal self-supply of the precipitants dispersed throughout the bulk material. This strategy can be readily expanded to other aluminum alloys, and could pave the way for developing corrosion-resistant high-strength metallic materials. This article is protected by copyright. All rights reserved.
PubMed: 38943609
DOI: 10.1002/adma.202406506 -
Nigerian Journal of Clinical Practice Jun 2024Apically extruded debris can be affected by some features of the file systems such as kinematics or metallurgic properties.
BACKGROUND
Apically extruded debris can be affected by some features of the file systems such as kinematics or metallurgic properties.
AIMS
This in vitro study aimed to evaluate the effect of movement kinematics (reciprocation or rotation) and heat-treated alloys (C.Wire) on the amount of debris extrusion.
METHODS
Seventy-two mesiobuccal root canals were assigned into three experimental groups related to the single-file system used (n = 24): two rotational; One Shape (Conventional Ni-Ti), One Curve (C.Wire), and one reciprocating; and One Reci (C.Wire). The file systems were used according to the advisable speed and torque according to the manufacturers' suggestion. The weight of debris was calculated by subtracting the preweights from postweights of Eppendorf tubes. Kruskall-Wallis and Mann-Whitney U tests were used to analyze the data (P = 0.05).
RESULTS
One Shape produced the greatest amount of extruded debris compared with One Curve (P < 0.001) and One Reci (P < 0.001), respectively. No statistical difference was found between One Curve and One Reci concerning amount of apical debris extrusion (P = 0.489).
CONCLUSION
Metallurgical properties of files may affect apical debris extrusion. Alloy type is an important factor in the amount of debris extrusion. File kinematics does not affect apical debris extrusion.
Topics: Humans; Alloys; Root Canal Preparation; Hot Temperature; Biomechanical Phenomena; In Vitro Techniques; Materials Testing; Equipment Design; Nickel; Dental Pulp Cavity
PubMed: 38943303
DOI: 10.4103/njcp.njcp_889_23 -
Advanced Science (Weinheim,... Jun 2024The vast high entropy alloy (HEA) composition space is promising for discovery of new material phases with unique properties. This study explores the potential to...
The vast high entropy alloy (HEA) composition space is promising for discovery of new material phases with unique properties. This study explores the potential to achieve rare-earth-free high magnetic anisotropy materials in single-phase HEA thin films. Thin films of FeCoNiMnCu sputtered on thermally oxidized Si/SiO substrates at room temperature are magnetically soft, with a coercivity on the order of 10 Oe. After post-deposition rapid thermal annealing (RTA), the films exhibit a single face-centered-cubic phase, with an almost 40-fold increase in coercivity. Inclusion of 50 at.% Pt in the film leads to ordering of a single L1 high entropy intermetallic phase after RTA, along with high magnetic anisotropy and 3 orders of magnitude coercivity increase. These results demonstrate a promising HEA approach to achieve high magnetic anisotropy materials using RTA.
PubMed: 38943261
DOI: 10.1002/advs.202308574 -
ACS Applied Materials & Interfaces Jun 2024Se-free n-type (Bi,Sb)Te thermoelectric materials, outperforming traditional n-type Bi(Te,Se), emerge as a compelling candidate for practical applications of recovering...
Se-free n-type (Bi,Sb)Te thermoelectric materials, outperforming traditional n-type Bi(Te,Se), emerge as a compelling candidate for practical applications of recovering low-grade waste heat. A 100% improvement in the maximum of n-type BiSbTe is demonstrated by using melt-spinning and excess Te-assisted transient liquid phase sintering (LPS). Te-rich sintering promotes the formation of intrinsic defects (Te), elevating the carrier concentration and enhancing the electrical conductivity. Melt-spinning with excess Te fine-tunes the electronic band, resulting in a high power-factor of 0.35 × 10 W·m K at 300 K. Rapid volume change during sintering induces the formation of dislocation networks, significantly suppressing the lattice thermal conductivity (0.4 W·m K). The developed n-type legs achieve a high maximum of 1.0 at 450 K resulting in a 70% improvement in the output power of the thermoelectric device (7.7 W at a temperature difference of 250 K). This work highlights the synergy between melt-spinning and transient LPS, advancing the tailored control of both electronic and thermal properties in thermoelectric technology.
PubMed: 38943223
DOI: 10.1021/acsami.4c06978