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Here, we report on a composite nanomechanical resonant magnetometer with magnetoelastic thin film integrated on the surface of a film bulk acoustic resonator (FBAR). By exploiting the delta-E effect of magnetoelastic thin film and resonance characteristic in piezoelectric thin film, we theoretically and experimentally demonstrate the capability to realize ultrahigh resonance frequency and excellent magnetic field sensitivity in such composite configuration, thereby greatly improving the limit of detection of weak magnetic field. The proposed FBAR-based resonant magnetometer achieves maximum magnetic sensitivity of 137 kHz/Oe in a proof-of-concept device without structural optimization, corresponding to a noise equivalent power as low as 7 nT/Hz1/2. Further study indicates that by optimizing the thicknesses of the magnetic sensitive layer and piezoelectric layer, an unprecedented sensitivity of 5 GHz/Oe with an exceptional limit of detection of weak magnetic field down to 190 ${f}\text{T}$ /Hz1/2 could be potentially achieved. Our work provides a forward new and exciting route toward ultralow magnetic field detection in civilian and military applications. [ABSTRACT FROM AUTHOR]

Adverse drug-drug interaction (ADDI) becomes a significant threat to public health. Despite the detection of ADDIs is experimentally implemented in the early development phase of drug design, many potential ADDIs are still clinically explored by accidents, leading to a large number of morbidity and mortality. Several computational models are designed for ADDI prediction. However, they take no consideration of drug dependency, although many drugs usually produce synergistic effects and own highly mutual dependency in treatments, which contains underlying information about ADDIs and benefits ADDI prediction. In this paper, we design a dependent network to model the drug dependency and propose an attribute supervised learning model Probabilistic Dependent Matrix Tri-Factorization (PDMTF) for ADDI prediction. In particular, PDMTF incorporates two drug attributes, molecular structure and side effect, and their correlation to model the adverse interactions among drugs. The dependent network is represented by a dependent matrix, which is first formulated by the row precision matrix of the predicted attribute matrices and then regularized by the molecular structure similarities among drugs. Meanwhile, an efficient alternating algorithm is designed for solving the optimization problem of PDMTF. Experiments demonstrate the superior performance of the proposed model when compared with eight baselines and its two variants. [ABSTRACT FROM AUTHOR]

Objective: The sliding motion of the liver during respiration violates the homogeneous motion smoothness assumption in conventional nonrigid image registration and commonly results in compromised registration accuracy. This paper presents a novel approach, registration with three-dimensional (3D) active contour motion segmentation (RAMS), to improve registration accuracy with discontinuity-aware motion regularization. Methods: A Markov random field-based discrete optimization with dense displacement sampling and self-similarity context metric is used for registration, while a graph cuts-based 3D active contour approach is applied to segment the sliding interface. In the first registration pass, a mask-free L1 regularization on an image-derived minimum spanning tree is performed to allow motion discontinuity. Based on the motion field estimates, a coarse segmentation finds the motion boundaries. Next, based on magnetic resonance (MR) signal intensity, a fine segmentation aligns the motion boundaries with anatomical boundaries. In the second registration pass, smoothness constraints across the segmented sliding interface are removed by masked regularization on a minimum spanning forest and masked interpolation of the motion field. Results: For in vivo breath-hold abdominal MRI data, the motion masks calculated by RAMS are highly consistent with manual segmentations in terms of Dice similarity and bidirectional local distance measure. These automatically obtained masks are shown to substantially improve registration accuracy for both the proposed discrete registration as well as conventional continuous nonrigid algorithms. Conclusion/Significance: The presented results demonstrated the feasibility of automated segmentation of the respiratory sliding motion interface in liver MR images and the effectiveness of using the derived motion masks to preserve motion discontinuity. [ABSTRACT FROM AUTHOR]

Novel image processing methods are presented in this work for 3D synthesis of multiview images and crosstalk reduction to improve the perceived image quality of lenticular autostereoscopic displays. First, for optimizing the intensity of a screen subpixel mapped to a fraction view number, a weighting method is proposed to blend the intensities of the corresponding subpixels from the two neighboring integer view images by minimizing the mean square error. Experimental results show that, comparing with the conventional rounding method, the proposed weighting method can effectively reduce the ghosting artifacts and sharpen the object boundaries when viewing at optimal integer viewpoints. Second, the crosstalk among vertical neighboring subpixels is modeled as a shift-invariant low-pass filter, and a novel computational efficient inverse filtering method is proposed for crosstalk reduction by applying fast Fourier transform (FFT) on each column of subpixels in the multiview interlaced screen image. In addition, a novel filtering method is proposed for determining the maximum input dynamic range of screen subpixel intensities. Experimental results demonstrate that the ghost image from neighboring views can be substantially diminished by the proposed inverse filtering method. [ABSTRACT FROM PUBLISHER]

Electromagnetic absorption and subsequent heating of nanoparticle solutions and simple NaCl ionic solutions is examined for biomedical applications in the radiofrequency range at 13.56 MHz. It is shown via both theory and experiment that for in vitro measurements the shape of the solution container plays a major role in absorption and heating. [ABSTRACT FROM PUBLISHER]