bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exosomes as a biomarker platform for detecting epidermal growth factor receptor–positive high-grade gliomas
Authors: Manda Sasidhar Venkata , Kataria Yogesh , Tatireddy Babul Reddy , Ramakrishnan Balasubramaniam , Ratnam Boola Gnana , Lath Rahul , Ranjan Alok , Ray Amitava 
Published: June 2017

OBJECTIVEHigh-grade glial brain tumors are often characterized by an elevated expression of the tumorigenic epidermal growth factor receptor variant III (EGFRvIII). The authors sought to establish a clinically adaptive protocol as a noninvasive diagnostic tool for EGFRvIII detection through serum exosomes.METHODSPurity of serum exosome/RNA was confirmed by electron microscopy and flow cytometry and through an RNA bioanalyzer profile. EGFRvIII amplification was initially established by semiquantitative polymerase chain reaction in tumor tissues and exosomes. Diagnostic performance of EGFRvIII transcript in tissue versus exosome was determined using a 2 × 2 clinical table approach. Overall survival was determined using Kaplan-Meier analysis.RESULTSThe EGFRvIII transcript was detected in 39.5% of tumor tissue samples and in 44.7% of their paired serum exosome samples; 28.1% of biopsy tumors coexpressed wild-type EGFR and EGFRvIII. Tissue EGFRvIII amplification served as the reference-positive control for its paired serum expression. The overall clinical sensitivity and specificity of semiquantitative exosome EGFRvIII polymerase chain reaction detection assay in serum were 81.58% (95% CI 65.67%–92.26%) and 79.31% (95% CI 66.65%–88.83%), respectively. Age, sex, tumor location, and side of the body on which the tumor was located had no effect on the detection rate of exosomal EGFRvIII transcript. EGFRvIII expression either in exosomes or tissue correlated with poor survival.CONCLUSIONSThe authors established a serum-based method for detection of EGFRvIII in high-grade brain tumors that might serve as an optimal noninvasive method for diagnosing EGFRvIII-positive high-grade gliomas.
Effect of different expansion strategies on coronary stent deployment in a tapered artery
Authors: Shen Xiang , Ji Song , Xie Zhongmin , Deng Yongquan 
Published: June 2017

BACKGROUND: Vascular stenting has been widely used to treat vessel stenosis. However, long-term successes of the procedure are often compromised by late stent thrombosis (ST) and in-stent restenosis (ISR), especially in tapered arteries. OBJECTIVE: The aim of this study was to choose a reasonable expansion strategy for tapered arteries. METHODS: A balloon-expandable coronary stent deployment in a tapered vessel was numerically studied fol-lowing three strategies: (i) selecting the proximal diameter of the tapered vessel as the reference diameter to expand the stent, (ii) selecting the middle diameter of the tapered vessel as the reference diameter to expand the stent, and (iii) selecting the distal diameter of the tapered vessel as the reference diameter to expand the stent. RESULTS: Computational results showed that the first expansion strategy resulted in the maximum vessel stress and the best stent apposition, while the third strategy resulted in the minimal vessel stress and the worst stent appo-sition. Meanwhile, the second expansion strategy achieved a trade-off between the first and third strategies, leading to acceptable vessel stress and stent apposition. CONCLUSIONS: The second expansion strategy is the most reasonable choice for tapered vessels, and it should be considered when implanting a stent.
Mastication noise reduction method for fully implantable hearing aid using piezo-electric sensor
Authors: Na Sung Dae , Lee Gihyoun , Wei Qun , Seong Ki Woong , Cho Jin Ho , Kim Myoung Nam 
Published: June 2017

BACKGROUND: Fully implantable hearing devices (FIHDs) can be affected by generated biomechanical noise such as mastication noise. OBJECTIVE: To reduce the mastication noise using a piezo-electric sensor, the mastication noise is measured with the piezo-electric sensor, and noise reduction is practiced by the energy difference. METHODS: For the experiment on mastication noise, a skull model was designed using artificial skull model and a piezo-electric sensor that can measure the vibration signals better than other sensors. A 1 kHz pure-tone sound through a standard speaker was applied to the model while the lower jawbone of the model was moved in a masticatory fashion. RESULTS: The correlation coefficients and signal-to-noise ratio (SNR) before and after application of the proposed method were compared. It was found that the signal-to-noise ratio and correlation coefficients increased by 4.48 dB and 0.45, respectively. CONCLUSION: The mastication noise is measured by piezo-electric sensor as the mastication noise that occurred during vibration. In addition, the noise was reduced by using the proposed method in conjunction with MATLAB. In order to confirm the performance of the proposed method, the correlation coefficients and signal-to-noise ratio before and after signal processing were calculated. In the future, an implantable microphone for real-time processing will be developed.
Comparative analysis of the stress distribution in five anatomical types of maxillary central incisor
Authors: Sun Lei , Wu Xifeng , Li Yang , Lin Zhenyan , Xu Duoling , Lin Xuan , Gao Yongbo 
Published: June 2017

BACKGROUND: The maxillary central incisor is one of the most important anatomical indicators in esthetics, and stress distribution may vary among its five anatomical views (labial, palatal, mesial, distal, and incisal). OBJECTIVE: To compare stress distribution among the five anatomical views of the maxillary central incisor under loading force at five angles and to observe and analyze the stress distribution in the dentin and periodontal ligament. METHODS: We established three-dimensional finite element models of the five different views, which simulated the bite force with a static load force at 0[Formula: see text], 30[Formula: see text], 45[Formula: see text], 60[Formula: see text], and 90[Formula: see text]. The stress and displacement values for the cementoenamel junction (CEJ)-apical labial, palatal, mesial, and distal and the equivalent stress values on the periodontal ligament of the maxillary central incisor were calculated. RESULTS: As the angle increased, the equivalent stress on the periodontal ligament, overall tooth displacement, equivalent stress, and displacement over the four views increased. The peaks of equivalent stress over the four views appeared within 0.8–17 mm below the CEJ, although all equivalent stress values decreased while approaching the peak. Within 1–19 mm below the CEJ, the equivalent stress over the M1 and P1 views of the maxillary central incisor decreased substantially. CONCLUSION: The peaks of the equivalent stress over the M1 and P1 views of the maxillary central incisor and their stress distribution were lower than those of the other three types. Our findings provided theoretical data on the biomechanics of this esthetically important tooth, which may be useful during implantation of missing maxillary central incisors.
Adaptive locomotor network activation during randomized walking speeds using functional near-infrared spectroscopy
Authors: Kim Ha Yeon , Kim Eun Joo , You Joshua (Sung) H. 
Published: June 2017

BACKGROUND: An improved understanding of the mechanisms underlying locomotor networks has the potential to benefit the neurorehabilitation of patients with neurological locomotor deficits. However, the specific locomotor networks that mediate adaptive locomotor performance and changes in gait speed remain unknown. OBJECTIVE: The aim of the present study was to examine patterns of cortical activation associated with the walking speeds of 1.5, 2.0, 2.5, and 3.0 km/h on a treadmill. METHODS: Functional near-infrared spectroscopy (fNIRS) was performed on a 30-year-old right-handed healthy female subject, and cerebral hemodynamic changes were observed in cortical locomotor network areas including the primary sensorimotor cortex (SMC), premotor cortex (PMC), supplementary motor area (SMA), prefrontal cortex (PFC), and sensory association cortex (SAC). The software package NIRS-statistical parametric mapping (NIRS-SPM) was utilized to analyze fNIRS data in the MATLAB environment. SPM t-statistic maps were computed at an uncorrected threshold of [Formula: see text] 0.00001. RESULTS: At faster walking speeds, oxygenated hemoglobin (OxyHb) was concentrated in the PFC and indicated globalized locomotor network activation of the SMC, PMC, SMA, and PMC; additionally, the site with the highest cortical activation ratio shifted from the SMC to the SMA. CONCLUSIONS: Global locomotor network recruitment, in particular PFC activation indicated by OxyHb in our study, may indicate a response to increased cognitive-locomotor demand due to simultaneous postural maintenance and leg movement coordination.
Effect of whole body vibration on lactate level recovery and heart rate recovery in rest after intense exercise
Authors: Kang Seung Rok , Min Jin-Young , Yu Changho , Kwon Tae-Kyu 
Published: June 2017

OBJECTIVE: In this paper, we investigated the recovery of the lactate level, muscular fatigue, and heart rate recovery (HRR) with respect to whole body vibration (WBV) during the rest stage after a gait exercise. METHODS: A total of 24 healthy subjects with no medical history of exercise injury participated. The participants were divided into a training group with vibration during rest and a control group with the same conditions but without vibration. The subjects performed a gait exercise with a slope of 15% and velocity of 4 km/h to consume 450 kcal in 30 min. Then, they rested on a vibrating chair or on a chair without vibrations for 30 min. The vibration protocol consists of a frequency of 10 Hz and amplitude of 5 mm. To estimate the recovery effect, we measured the lactate levels in blood, spectral edge frequency (SEF) of MVIC, and HRR before, immediately after exercise, and after rest. RESULTS: The results showed that the lactate level in the training group decreased more (93.8%) than in the control group (32.8%). Also, HRR showed a similar trend with a recovery of 88.39% in the training group but 64.72% in the control group. We considered that whole-body vibrations during rest would help remove lactic acid by improving the level of lactic acid oxidation with stimulated blood vessels in the muscles and by helping to maintain blood flow. Also, WBV would lead to compensation to actively decrease the fast excess post-exercise oxygen consumption from blood circulation. CONCLUSIONS: We suggest that whole-body vibrations during rest can provide fast, efficient fatigue recovery as a cool down exercise for women, the elderly, and patients without other activity after intense exercise.
A comparative study on the mechanical behavior of intervertebral disc using hyperelastic finite element model
Authors: Xie Feng , Zhou Honghai , Zhao Wenju , Huang Lixin 
Published: June 2017

BACKGROUND: Lumbar disc herniation may result in excruciating pain due to it being one of the most common diseases related to changes of intervertebral disc (IVD). In order to find a better clinical treatment and prevention scheme for relieving the pain caused by spine degeneration, the mechanical behavior analysis of IVD must be studied. OBJECTIVE: A finite element method (FEM) is used in this study to analyze the mechanical behaviors of healthy and herniated IVD. METHOD: In order to compare the responses of IVD under different loading conditions for the annulus fibrosus of IVD, the hyperelastic and elastic constitutive FE models were used in the FEM. RESULTS: The comparison shows that hyperelastic FE models have a much better capability to describe the mechanical behaviors of the IVD than elastic FE models. It can be found from FE simulation that there was a higher stress concentration at the annulus fibrosus of the herniated disc than the healthy disc. CONCLUSIONS: Higher stress concentration resulted in more damage and ease of bringing out lumbar disc herniation. Numerical examples of FE simulation indicate that the FEM with hyperelastic constitutive model has very good capability for analyzing the mechanical behaviors of IVD.
The force control and path planning of electromagnetic induction-based massage robot
Authors: Wang Wendong , Zhang Lei , Li Jinzhe , Yuan Xiaoqing , Shi Yikai , Jiang Qinqin , He Lijing 
Published: June 2017

BACKGROUND: Massage robot is considered as an effective physiological treatment to relieve fatigue, improve blood circulation, relax muscle tone, etc. The simple massage equipment quickly spread into market due to low cost, but they are not widely accepted due to restricted massage function. Complicated structure and high cost caused difficulties for developing multi-function massage equipment. OBJECTIVE: This paper presents a novel massage robot which can achieve tapping, rolling, kneading and other massage operations, and proposes an improved reciprocating path planning algorithm to improve massage effect. METHODS: The number of coil turns, the coil current and the distance between massage head and yoke were chosen to investigate the influence on massage force by finite element method. The control system model of the wheeled massage robot was established, including control subsystem of the motor, path algorithm control subsystem, parameter module of the massage robot and virtual reality interface module. The improved reciprocating path planning algorithm was proposed to improve regional coverage rate and massage effect. RESULTS: The influence caused by coil current, the number of coil turns and the distance between massage head and yoke were simulated in Maxwell. It indicated that coil current has more important influence compared to the other two factors. The path planning simulation of the massage robot was completed in Matlab, and the results show that the improved reciprocating path planning algorithm achieved higher coverage rate than the traditional algorithm. CONCLUSIONS: With the analysis of simulation results, it can be concluded that the number of coil turns and the distance between the moving iron core and the yoke could be determined prior to coil current, and the force can be controllable by optimizing structure parameters of massage head and adjusting coil current. Meanwhile, it demonstrates that the proposed algorithm could effectively improve path coverage rate during massage operations, therefore the massage effect can be improved.
Differential barometric-based positioning technique for indoor elevation measurement in IoT medical applications
Authors: Wang Hua , Wen Yingyou , Zhao Dazhe 
Published: June 2017

BACKGROUND: Medical applications have begun to benefit from Internet of Things (IoT) technology through the introduction of wearable devices. Several medical applications require accurate patient location as various changes affect pressure parameters inside the body. OBJECTIVE: This study aims to develop a system to measure indoor altitude for IoT medical applications. METHODS: We propose a differential barometric-based positioning system to estimate the altitude between a reference sensor and a localizing sensor connected to the human body. The differential barometric altimetry model is introduced to estimate indoor elevations and eliminate environmental artifacts. In addition, a Gaussian filter processing is adopted to remove noise from the elevation measurements. The proposed system is then investigated through extensive experiments, using various evaluation criteria. RESULTS: The results indicate that the proposed system yielded good accuracy with reduced implementation complexity and fewer costs. CONCLUSIONS: The proposed system is resilient compared to other indoor localization approaches, even when numerous environmental artifacts in indoor environments are present.
Cellular neural network modelling of soft tissue dynamics for surgical simulation
Authors: Zhang Jinao , Zhong Yongmin , Smith Julian , Gu Chengfan 
Published: June 2017

BACKGROUND: Currently, the mechanical dynamics of soft tissue deformation is achieved by numerical time integrations such as the explicit or implicit integration; however, the explicit integration is stable only under a small time step, whereas the implicit integration is computationally expensive in spite of the accommodation of a large time step. OBJECTIVE: This paper presents a cellular neural network method for stable simulation of soft tissue deformation dynamics. METHOD: The non-rigid motion equation is formulated as a cellular neural network with local connectivity of cells, and thus the dynamics of soft tissue deformation is transformed into the neural dynamics of the cellular neural network. RESULTS: Results show that the proposed method can achieve good accuracy at a small time step. It still remains stable at a large time step, while maintaining the computational efficiency of the explicit integration. CONCLUSION: The proposed method can achieve stable soft tissue deformation with efficiency of explicit integration for surgical simulation.
Medical image watermarking using bit threshold map based on just noticeable distortion in discrete cosine transform
Authors: Seo Hyeon-Uk , Wei Qun , Kwon Seong-Geun , Sohng Kyu-Ik 
Published: June 2017

BACKGROUND: Medical images stored in a hospital system are generally confidential and integrated and require strict security. However, medical information stored on digital medical imaging systems, as well as picture archiving and communication systems (PACS), are vulnerable to attack when the data are transferred over wireless or wired communication networks. OBJECTIVE: To solve this problem, a watermarking algorithm for medical images is proposed using a bit threshold map based on just noticeable distortion (JND) in the discrete cosine transform (DCT) method. METHODS: The low-frequency component comprises a considerable amount of the signal energy for most images. As a result, it has a crucial effect on the image quality. Therefore, in this paper, the proposed algorithm embeds watermarks based on the low-frequency components of the image, such as the DC coefficient of the DCT. RESULTS: When watermarks are embedded in a low frequency area, the subjective image quality is often degraded. To compensate for the degradation of the imperceptibility of the watermarking system, which results from embedding watermarks in the low-frequency component, this research considers the human visual system. In addition, the embedding strength of the JND value is used to improve the watermarking imperceptibility. CONCLUSIONS: We applied the proposed watermarking algorithm to a variety of medical images using a computer simulation. The algorithm’s performance was verified using a variety of attacks for eliminating watermarks. The simulation results show that the proposed algorithm robustly provides protection against a variety of possible attacks.
A new idea for visualization of lesions distribution in mammogram based on CPD registration method
Authors: Pan Xiaoguang , Qi Buer , Yu Hongfei , Wei Haiping , Kang Yan 
Published: June 2017

BACKGROUND: Mammography is currently the most effective technique for breast cancer. Lesions distribution can provide support for clinical diagnosis and epidemiological studies. OBJECTIVE: We presented a new idea to help radiologists study breast lesions distribution conveniently. We also developed an automatic tool based on this idea which could show visualization of lesions distribution in a standard mammogram. METHODS: Firstly, establishing a lesion database to study; then, extracting breast contours and match different women’s mammograms to a standard mammogram; finally, showing the lesion distribution in the standard mammogram, and providing the distribution statistics. The crucial process of developing this tool was matching different women’s mammograms correctly. We used a hybrid breast contour extraction method combined with coherent point drift method to match different women’s mammograms. RESULTS: We tested our automatic tool by four mass datasets of 641 images. The distribution results shown by the tool were consistent with the results counted according to their reports and mammograms by manual. We also discussed the registration error that was less than 3.3 mm in average distance. CONCLUSIONS: The new idea is effective and the automatic tool can provide lesions distribution results which are consistent with radiologists simply and conveniently.
High-mass Star Formation in the Outer Scutum–Centaurus Arm
Authors: Armentrout W. P. , Anderson L. D. , Balser Dana S. , Bania T. M. , Dame T. M. , Wenger Trey V. 
Published: June 2017

Abstract
The Outer Scutum–Centaurus (OSC) spiral arm is the most distant molecular spiral arm in the Milky Way, but until recently little was known about this structure. Discovered by Dame and Thaddeus, the OSC lies ∼15 kpc from the Galactic Center. Due to the Galactic warp, it rises to nearly 4° above the Galactic Plane in the first Galactic quadrant, leaving it unsampled by most Galactic plane surveys. Here we observe H ii region candidates spatially coincident with the OSC using the Very Large Array to image radio continuum emission from 65 targets and the Green Bank Telescope to search for ammonia and water maser emission from 75 targets. This sample, drawn from the Wide-field Infrared Survey Explorer Catalog of Galactic H ii Regions, represents every H ii region candidate near the longitude–latitude

locus of the OSC. Coupled with their characteristic mid-infrared morphologies, detection of radio continuum emission strongly suggests that a target is a bona fide H ii region. Detections of associated ammonia or water maser emission allow us to derive a kinematic distance and determine if the velocity of the region is consistent with that of the OSC. Nearly 60% of the observed sources were detected in radio continuum, and more than 20% have ammonia or water maser detections. The velocities of these sources mainly place them beyond the Solar orbit. These very distant high-mass stars have stellar spectral types as early as O4. We associate high-mass star formation at 2 new locations with the OSC, increasing the total number of detected H ii regions in the OSC to 12.