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Purpose: Periodontal ligament cells (PDLCs) play a significant role in orthodontic force induced bone remodeling. However, the molecular mechanisms by which PDLCs respond to mechanical stimuli and influence osteoclastic activities remain unclear. This study aims to investigate the role of UCHL1, a key deubiquitinating enzyme involved in protein degradation and cellular responses, in force-treated PDLCs during orthodontic tooth movement (OTM). Materials and Methods: In this study, we conducted in vivo and in vitro experiments using human PDLCs and a rat model of OTM. Mechanical stress was applied to PDLCs, and UCHL1 expression was analyzed through quantitative real-time polymerase chain reaction (qPCR), Western blot, and immunofluorescence staining. UCHL1 knockdown was achieved using siRNA, and its effects on osteoclast differentiation were assessed. The role of the MAPK/ERK pathway was investigated using the MEK-specific inhibitor U0126. An animal model of OTM was established, and the impact of UCHL1 inhibitor-LDN57444 on OTM and osteoclastic activity was evaluated through micro-CT analysis, histological staining, and immunohistochemistry. Results: Mechanical force induced UCHL1 expression in PDLCs during OTM. UCHL1 knockdown downregulated the RANKL/OPG ratio in PDLCs, affecting osteoclast differentiation. LDN57444 inhibited OTM and osteoclastic activity. UCHL1 activation correlated with ERK1/2 phosphorylation in force-treated PDLCs. Conclusions: Mechanical force mediated UCHL1 activation in PDLCs promotes osteoclast differentiation via the ERK1/2 signaling pathway during OTM. [ABSTRACT FROM AUTHOR]

A novel flexible restrict reducer is proposed. This reducer is a two stages conical cylindrical gear reducer. The setting element of conical gear and cylindrical gear is pre-tighten belleville spring. There is no axial movement of the gears while the gear axial force is lower than the spring force,the location is accuracy.On the contrary,the spring deforms for absorbing energy to avoid permanent deformation applied by direct axial force. The 3 D model of the flexible restrict reducer is built by UG 8. 0 and the transient dynamics analysis under specified load is carried out by the ANSYS Work Bench. The theoretical feasibility of flexible restrict reducer is verified by the simulation result.

Object detection is an essential task for autonomous vehicles to ensure safety. Due to the complexity of mining environments, it is difficult to detect objects accurately and robustly. To address these issues, this paper proposes a novel 3D LiDAR-based object detection method fusing semantic and geometric features for autonomous trucks in mining environments (3DSG). A road region extraction method is presented by establishing a semantic segmentation network with a region searching strategy to eliminate off-road point clouds. To deal with the complexity of unstructured road ground point-cloud segmentation, we propose a cascaded ground detection algorithm by performing semantic segmentation filtering and rectangular grid map filtering. A clustering method is proposed fusing adaptive distance thresholds of Euclidean clusters with semantic segmentation categories to solve the problem of the over- and undersegmentation of objects caused by the sparsity of point clouds. The performance of the proposed method is examined utilizing a real mining dataset named TG-Mine-3D. Compared with state-of-the-art methods, our method achieved higher precision of 66.39%. Moreover, for the truck and pedestrian categories, the performance of our method was significantly improved by 2.66% and 5.80%, respectively. The proposed method running at 51.35 ms achieved real-time performance. [ABSTRACT FROM AUTHOR]

Touch shape discrimination is not only closely related to tactile mechanoreceptors but also higher cognitive function. However, previous shape discrimination methods are difficult to complete in a short time, and the devices are complicated to operate and not user-friendly for nonprofessionals. Here, we propose a new method, the evaluation quantity of which is the angle discrimination threshold. In addition, to make this method easy to use for nonprofessionals, we designed a haptic angle sorting system, including the device and software. To evaluate this method, the angle sorting and two-angle discrimination experiments were compared, and it was found that participants spent significantly less time in the former experiment than in the latter. At the same time, there is a strong correlation between the performance of angle sorting and two-angle discrimination, which shows that the angle threshold obtained by the new method can also be used to evaluate the ability of touch discrimination. Moreover, the angle sorting results of different age groups also further demonstrate the feasibility of the method. The efficiency of this new method and the effectiveness of the system also provide a convenient means for evaluating haptic shape discrimination, which may have potential clinical application value in the early diagnosis of peripheral neuropathy and even in the evaluation of cognitive function. [ABSTRACT FROM AUTHOR]

This paper introduces a novel Euler-angle-based adaptive attitude filter for micro-electro-mechanical system inertial measurement unit (IMU)/magnetometer fusion. An intelligent coordinate switch algorithm is proposed to overcome the singularity problem that exists in the Euler-angle-based attitude calculation approach. This method rotates the physical IMU body frame and forms a quasi-computational coordinate to perform the attitude and filter update. In addition, a novel noise estimation theorem based on redundant measurement systems is introduced, proofed and employed to adaptively tune the measurement covariance matrix R in the filter. This algorithm uses gyroscope short-term accuracy to evaluate the attitude performance derived from different sensors and optimally assigns weight in the filter update. Simulated and practical experiments are carried out to test the validation of the proposed adaptive attitude filter. The results achieved demonstrate that this approach can provide a promising orientation solution. [ABSTRACT FROM AUTHOR]

Light-emitting diodes (LEDs) with high response frequency and high power can be applied in visible light communication (VLC). This letter studies the response frequency and optical output power of the gallium nitride (GaN) based matrix micro-LED ($\mu $ LED) for visible light communication. The blue-emitting GaN $\mu $ LEDs with the format from ${1}\times {1}$ to ${6}\times {6}$ are fabricated and used to analyze the relationship between the matrix format and the response frequency, as well as the output optical power and the data transmission performance of the matrix $\mu $ LED. The experimental and analysis results show that the GaN-based matrix $\mu $ LED response frequency can be improved by an increase in the injection current density increased and a decrease in device capacitance. The experimental comparison result indicates that the −3 dB response frequency changed from 85 MHz to 401 MHz at a 60 mA injection current progressively increased as the matrix array size from ${1}\times {1}$ to ${6}\times {6}$ , the ${6}\times {6}$ matrix $\mu $ LED optical output power reaches a value of 356.7 mW. [ABSTRACT FROM AUTHOR]

This paper investigated the effect of water reducing agent types and dosages on the workability, hydration process and strength development of building gypsum, which aimed to understand the adaptation and enhancement effect of different types of water reducing agent in this gypsum. The results indicated that naphthalene water reducing agent (FDN) showed an ineffective reducing effectiveness. FDN increased the hydration process and shortened the setting time, while time-dependent workability loss. On the other hand, polycarboxylate superplasticizer (Point-S) gave a higher water reducing effectiveness which delayed the hydration process. The setting time was prolonged by using Point-S and the time-dependent workability loss was also reduced. The critical dosage was 0.5% and gave a 75% increase of compressive strength. [ABSTRACT FROM AUTHOR]

Through-silicon vias (TSV) will speed up interconnections between chips. Manufacturable and cost-effective TSVs will allow faster computer systems. In this paper, we report the successful formation of seed layers for plating copper TSVs with aspect ratios greater than 25:1. Following the rapid atomic layer deposition (ALD) of a conformal insulating layer of silica inside the silicon vias, manganese nitride (Mn4N) is deposited conformally on the silica surface by chemical vapor deposition (CVD). Mn4N forms an effective copper diffusion barrier and provides strong adhesion between the silica and the subsequently-deposited copper. Conformal copper or copper-manganese alloy films are then deposited by an iodine-catalyzed direct-liquid-injection (DLI) CVD process. Diffusion of manganese during post-deposition annealing further enhances the barrier and adhesion properties at the copper/dielectric interface, Chemistry and Chemical Biology

An interlayer of face centered cubic (fcc) Co4N has demonstrated significant improvements in adhesion between copper and diffusion barrier layers. This fcc phase of Co4N was prepared by chemical vapor deposition (CVD) using bis(N-tert-butyl-N′-ethyl-propionamidinato)cobalt(II) and a reactant mixture of NH3 and H2 at substrate temperatures from 100 to 180°C. The Co/N atomic ratio and the phase of cobalt nitride film can be modified by adjusting the ratio of NH3 and H2 in the gas feedstock. The cobalt nitride films prepared by CVD are smooth, highly conformal, and stable against intermixing with copper up to at least 400°C. This fcc cobalt nitride material has very strong adhesion to copper due to the small lattice mismatch (−1 to 2%) between \(fcc-Co_4N\) and fcc Cu. Copper wires should be stabilized against failure by electromigration when fcc cobalt nitride interlayers are placed between the copper and surrounding diffusion barriers., Chemistry and Chemical Biology, Engineering and Applied Sciences

Smooth and continuous films of nickel nitride (NiNx) with excellent step coverage were deposited from a novel nickel amidinate precursor, Ni(MeC(NtBu)2)2, and either ammonia (NH3) or a mixture of NH3 and hydrogen (H2) gases as co-reactants. The reactants were injected together in direct-liquid-injection chemical vapor deposition (DLI-CVD) processes at substrate temperatures of 160−200 °C. Depending on the ratio of NH3 to H2 gases during deposition, the Ni:N atomic ratio in DLI-CVD NiNx films could be varied from 3:1 to 15:1, having either a cubic nickel structure or a mixture of hexagonal Ni3N and cubic Ni4N crystal structures with an incorporation of nitrogen as low as 6%. The chemical vapor deposition (CVD) growth rates of NiNx could be increased to more than 5 nm/min. The CVD films were smooth and continuous, and they had 100% step coverage in high-aspect-ratio (>50:1) holes. The as-deposited NiNx films had resistivities as low as 50 μΩ cm for film thicknesses of 25 nm. Annealing of the films in H2 at 160 °C or hydrogen plasma treatment at room temperature removed the nitrogen and led to pure nickel films., Chemistry and Chemical Biology

Lanthanum-based ternary oxide \(La_xM_{2−x}O_3\) (M = Sc, Lu, or Y) films were deposited on HF-last Si substrates by atomic layer deposition. Both \(LaScO_3\) and \(LaLuO_3\) films are amorphous while the as-deposited \(La_xY_{2−x}O_3\) films form a polycrystalline layer/amorphous layer structure on Si. Transmission electron microscopy and electrical analysis show the absence of interfacial layers. The dielectric constants for \(LaScO_3\), \(LaLuO_3\), and \(La_{1.23}Y_{0.77}O_3\) films are \(\sim 23\), \(28 \pm 1\), and \(17 \pm 1.3\), respectively, with leakage current density up to 6 orders of magnitude lower than that of thermal \(SiO_2\) with the same effective oxide thickness. Conformal coating thickness is demonstrated on holes with aspect ratio \(\sim 80:1\)., Chemistry and Chemical Biology

Three new ruthenium amidinate complexes were prepared: tris(diisopropylacetamidinato)-ruthenium(III), Ru(iPrNC(Me)NiPr)3 4; bis(diisopropyl-acetamidinato)ruthenium(II) dicarbonyl, Ru(iPrNC(Me)NiPr)2(CO)2 5; and bis(ditert- butylacetamidinato)ruthenium(II) dicarbonyl, Ru(tBuNC(Me)NtBu)2(CO)2 6. They have been synthesized and characterized by 1H NMR, TG and X-ray structure analysis. These three complexes were found to be monomeric and air stable. Compound 6 was found to have sufficient volatility and thermal stability for use in chemical vapor deposition (CVD) and atomic layer deposition (ALD) of ruthenium metal films., Chemistry and Chemical Biology

Amorphous LaAlO3 films were deposited on hydrogen-terminated silicon substrates by atomic layer deposition (ALD) at 300 oC. The precursors were lanthanum tris(N,N'-diisopropylformamidinate), trimethylaluminum (TMA) and water. Capacitance-voltage measurements made on ALD MoN/LaAlO3/Si stacks showed humps especially at low frequencies. They were effectively removed by O2 treatment at 300 o C without affecting the dielectric constant (kappa~15). The O2 treatment can be carried out either after deposition of a LaAlO3 film, or after each ALD cycle. The O2 treatment also lowered the leakage current from 80 mA cm-2 to 1 mA cm-2 for EOT = 1.3 nm. This indicates that oxygen vacancies are the main defects in as-deposited LaAlO3. Oxygen treated LaAlO3 is one of the best candidates for future high-kappa dielectric material due to its low leakage, low defect density and abrupt interface with silicon., Chemistry and Chemical Biology

The effect of H2O and O3 oxidants on the behavior of residual C and N-related impurities as well as Si out-diffusion and interfacial layer formation in atomic-layer-deposited La2O3 films grown at 250 °C were examined using in situ x-ray photoelectron spectroscopy. The silicate formation was suppressed in a La2O3 film grown using O3 compared to that deposited using H2O, but interfacial layer growth was enhanced. The accumulation of C and N-related residues with low binding energy, which originated from incomplete reactions, was suppressed in La2O3 films grown using O3. However, the use of O3 resulted in La-carbonate phase in film. [ABSTRACT FROM AUTHOR]

This paper presents a novel approach for hand-held low-cost MEMS (micro-electro-mechanical system) gyroscope in-self calibration. This method does not need the support of external high-precision equipment compared with traditional calibration scheme and can be accomplished by user hand rotation. In this approach, Kalman filter is designed to perform the calibration procedure and estimate gyroscope bias error, scale factor error and non-orthogonal error. The system observability is analyzed and the dynamic rotating conditions under which the sensor errors become observable are derived. The design principles of optimal calibration procedure are provided as well. Both simulated and practical experiments are carried out to test the validation of the proposed calibration algorithm. The achieved results demonstrate that the introduced approach can provide promising calibration scheme for the low-cost MEMS gyroscope. [ABSTRACT FROM AUTHOR]