Select search scope: search across all journals or within the current journal
Open accessResearch articleFirst published January, 2019pp. 1-1
Open accessResearch articleFirst published January, 2019pp. 3-13Children struggle to fall asleep by themselves because of their physiological characteristics. Therefore, research has been carried on various devices (such as a smartphone) to assist in improving the sleep quality of children. However, all such devices need to be controlled by parents and do not have functions for monitoring the sleep environment.
In this paper, a smart sleep-lighting system that includes a sleep-lighting device and a smartphone dongle is developed to improve the sleep environment of children.
The temperature, humidity, and luminance of the sleep environment are monitored and analyzed by the sleep-lighting device to control multi-color light and audio components. The colored light emitted by the multi-color light can be adjusted to improve the sleep atmosphere. Also, the audio component can play white noise to induce sleep. In addition, parents can use a smartphone dongle with a multi-channel wireless communication method to monitor and control one or more lighting devices in different locations in real time.
For environmental monitoring, average difference between proposed device and commercial sensor from chamber setting temperature 15
The manufactured sleep-lighting device has a high-precision temperature and humidity sensor and a luminance sensor that can accurately monitor the sleeping environment. The lighting device can play white noise to induce sleep in children. Also, a multi-color LED light is operated via a smartphone application to improve the sleep atmosphere. The measured data will be sent to the lighting device and processed together with sleep environment data in order to improve the sleep quality. Additionally, the final system will be tested for real end-users with clinical experiments by sleep research center of a university hospital.
Open accessResearch articleFirst published January, 2019pp. 15-22A load carrying task was identified as a major factor leading to slip and fall injuries such as overexertion and bodily reaction. Holding a load in front of the body while walking would shift the whole body center-of-mass to the front, loading additional rotational torque at the foot-ground contact.
The present study evaluated if carrying a load would increase the likelihood of slip initiation and the slip severity.
Eleven young and 10 older adults participated in the present study. A dry surface or a slippery surface was introduced while walking. Slip distance, peak sliding heel velocity, heel contact velocity, and required coefficient of friction were measured to test the study hypotheses.
The results showed that significant main effects were found in slip distance, and peak sliding heel velocity and no main effect were found in heel contact velocity and required coefficient of friction.
In conclusion, younger adults were found to slip longer and faster on the slippery surface while carrying a load. On the contrary, the older adults employed a safety-centered gait adaptation while carrying, to maintain slip initiation and severity characteristics at the same level as normal walking. Furthermore, light load carriage at 10% of body weight was suggested as a safe task for the elderly.
Open accessResearch articleFirst published January, 2019pp. 23-30Patent foramen ovale (PFO) and obstructive sleep apnea (OSA) are independent risk factors for young conscious stroke which may also be concomitant symptoms with it. But there is no sufficient attention on these phenomena.
To investigate the relationship between PFO, OSA and young stroke, and to look for proper treatment.
Three patients with young conscious stroke were reported, each of them was combined with PFO and OSA. All patients were diagnosed as wake-up stroke (WUS). Contrast-enhanced transcranial doppler ultrasound (c-TCD) and polysomnography (PSG) test were used for auxiliary diagnosis.
Right-to-left shunts and moderate to severe sleep apnea were observed. Increased body mass index (BMI), hemoglobin (HGB) and hematocrit (HCT) index were also observed. After continuous positive airway pressure (CPAP) therapy, the number of microbubbles was reduced in one patient.
These suggest that coexistence of PFO and OSA may associate with a greater risk of youth stroke. Decrease risk of stroke might occur if treating with CPAP in patients with OSA.
Open accessResearch articleFirst published January, 2019pp. 31-46In the practical implementation of control of electromyography (sEMG) driven devices, algorithms should recognize the human’s motion from sEMG with fast speed and high accuracy. This study proposes two feature engineering (FE) techniques, namely, feature-vector resampling and time-lag techniques, to improve the accuracy and speed of least square support vector machine (LSSVM) for wrist palmar angle estimation from sEMG feature. The root mean square error and correlation coefficients of LSSVM with FE are 9.50
Open accessResearch articleFirst published January, 2019pp. 47-57In the classical process, it was proven that ABPM data were the most significant attributes both by physician and ranking algorithms for dipper/non-dipper pattern classification as mentioned in our previous papers. To explore if any algorithm exists that would let the physician skip this diagnosis step is the main motivation of the study.
The main goal of the study is to build up a classification model that could reach a high-performance metrics by excluding ABPM data in hypertensive and non-diabetic patients.
The data used in this research have been drawn from 29 hypertensive patients without diabetes in endocrinology clinic of Marmara University in 2011. Five of 29 patient data were later removed from the dataset because of null data.
The findings showed that dipper/non-dipper pattern can be classified by artificial neural network algorithms, the highest achieved performance metrics are accuracy 87.5%, sensitivity 71%, and specificity 94%.
This novel method uses just two attributes: Ewing-score and HRREP. It offers a fast and low-cost solution when compared with the current diagnosis procedure. This attribute reduction method could be beneficial for different diseases using a big dataset.
Open accessResearch articleFirst published January, 2019pp. 59-66In 2005, global cardiovascular diseases caused 30% of deaths in Europe, which is 46% of total deaths for all death groups. Today, according to the International Adult Diabetes Federation, 20% to 25% of the adult population in the world has Metabolic Syndrome. Turkish Statistical Institute claims that in Turkey 408782 people died of circulatory system diseases in 2016 and it is expected that numbers will dramatically increase. In 2003, total worldwide healthcare budget of Diabetes Mellitus was up to 64.9 billion International Dollars with the continuing rise in prevalence, it is expected that total costs will increase to 396 billion International Dollars by 2025.
The main purpose of this study was to present a clinical decision support system that calculates Metabolic Syndrome existence and evaluate HeartScore risk level for Turkish population. The second objective was to create a detailed personal report about individual’s risk level of Metabolic Syndrome and HeartScore and give advice to him/her to reduce it. The fuzzy logic risk assessment system (FLRAS) was formed in LabVIEW graphical development platform according to International Diabetes Federation and European Heart Journal’s criteria. Mamdani type fuzzy logic sets were identified for each input variable and membership functions were assigned depending on the magnitude of the input limits. System’s performance was tested on 96 (72 females, 24 males) patient data. Results show that the proposed system was able to evaluate the Metabolic Syndrome risk with 0.9285 specificity, 0.92708 accuracy and 0.925 sensitivity.
Open accessResearch articleFirst published January, 2019pp. 67-84In recent years, drug-abuse problem is growing by leaps and bounds all over the world. The master minds spearheading its proliferation among the youth are difficult to identify, so drug-abuse case has become a hard nut to crack even with the help of best international experts in forensic science and criminology. Because most nations have tightened their controls on traditional drugs, the younger generation is now hooked onto new-type drugs: 1-(3- trifluoromethylphenyl) piperazine (TFMPP), 1-(3-chlorophenyl) piperazine (mCPP) and other new piperazine-drugs, acting as hallucinogens like ‘ecstasy’, are being consumed by vulnerable masses all over the world. However, only few research studies have focused on developing highly effective detection methods for TFMPP and mCPP in biological fluids; the number of detection methods for these new-type drugs is almost nil in China. Therefore, it is difficult to detect and prevent drug abuse cases related to piperazine drugs in China. There is an urgent need to develop some simple, fast, and reliable methods for detecting piperazine-drugs in vulnerable masses. Thus, the development of novel detection methods with high sensitivity and selectivity is a difficult task for the officials working in the department of forensic science in China. In this work, a new method was developed for the detection of piperazine derivatives: it was performed under the various specific conditions required for conducting chromatography and mass spectrometry analysis. With this novel method, TFMPP and mCPP was successfully detected with high accuracy in various biological samples. By comparing the purification effect of different solid-phase extraction columns for TFMPP and mCPP in biological fluids (urine and blood), we confirmed the validity of the novel method. In addition, this method has good linear relationship and a low detection line when GC/MS was performed for detecting TFMPP, mCPP in the biological fluids (urine and blood). It is a simple, reproducible method that is highly specific in the detection of piperazine-drugs. Thus, it is indeed a reliable method in forensic science.
Open accessResearch articleFirst published January, 2019pp. 85-93Biomarker selection or feature selection from survival data is a topic of considerable interest. Recently various survival analysis approaches for biomarker selection have been developed; however, there are growing challenges to currently methods for handling high-dimensional and low-sample problem. We propose a novel Log-sum regularization estimator within accelerated failure time (AFT) for predicting cancer patient survival time with a few biomarkers. This approach is implemented in path seeking algorithm to speed up solving the Log-sum penalty. Additionally, the control parameter of Log-sum penalty is modified by Bayesian information criterion (BIC). The results indicate that our proposed approach is able to achieve good performance in both simulated and real datasets with other
Open accessResearch articleFirst published January, 2019pp. 95-108Effective and skin doses gain much attention since the cardiac catheterization laboratory (CCL) is a place where both patients and medical staff are exposed to X-ray or fluoroscopy environment and gain a cumulative dose during the cardiac interventional procedure.
These doses for pediatric and adult patients undergone cardiac interventional examination using five PMMA phantoms and thermoluminescence dosimeter (TLD)/ionization chamber technique were estimated in this work with the further clinical verification.
Five PMMA phantoms (10, 30, 50, 70, and 90 kg) were customized to represent baby, child, adult female, adult male, and overweight adult (by Asian complexion standards), respectively, in accordance with the ICRU-48 report. Each phantom could be disassembled into 31 plates to insert TLD chips for measuring X-ray exposed dose or assisted with an auxiliary plate to insert high-sensitivity ionization chamber for surveying low-energy fluoroscopy dose.
The data acquired from five phantoms were integrated into four semi-empirical formulas, in order to fit the binary quadratic form “Dose
The model refinement with DAP share adjustment is envisaged.
Open accessResearch articleFirst published January, 2019pp. 109-121The morbidity of breast cancer has continuously achieved a global topicality. In particular, during the last decade several ten thousand female adults in Taiwan have been confirmed as breast cancer patients.
To predict the survival rate of breast cancer patients at various (0-IV) stages and provide efficient assessment of proposed radiotherapy for patients.
The prediction algorithm proposed is based on the revised hit and target model and implies the application of Taylor series expansion to the population-based survey dataset. The proposed algorithm features a specific function comprising a single simple exponential term
Its calculated values for breast cancer patients who undergone radiotherapy at different stages 0-IV were {0.0029, 0.0066, 0.0178, 0.0475, 0.1785} yr
The revised algorithm successfully interpreted the breast cancer patients’ survival rate at stages 0-IV and evaluated the necessity of radiotherapy for patients at various stages as well.
Open accessResearch articleFirst published January, 2019pp. 123-132Stroke is the most prevalent neurological disease and often leads to disability. Stroke can affect a person’s daily life, for example, its typical feature is the decline in the patient’s upper limbs. In order to reduce the sports injury of stroke patients, the best method is to carry out certain rehabilitation training.
In this paper, inverse kinematic analysis and trajectory planning of a modular upper limb rehabilitation exoskeleton are proposed.
The reverse coordinate system method is applied to solve inverse kinematics of the exoskeleton with a non-spherical joint in the wrist. For verifying the effectiveness of the algorithms, the smooth round-trip trajectory movement in joint place is designed and simulated.
The reverse coordinate system method can simplify the calculation process compared with the normal coordinate system. Smooth round-trip trajectory planning is simulated to generate a smooth trajectory curve.
The developed inverse kinematics algorithm and trajectory planning method are effective.
Open accessResearch articleFirst published January, 2019pp. 133-142Compared to laser, light-emitting diodes – non-coherent and divergent light sources requires that the developed optical system support steering and focusing of light on the desired target when acquiring information regarding human tissues.
A new optical system with an ultrawide angle was designed to cover large areas of the eye, including facial areas near the eye, in order to overcome the limited field of view of optical systems used for ophthalmology and dermatology applications.
To achieve a compact and handheld optical system for ophthalmology and dermatology applications, a contrast auto-focus (AF) method must be used, and the weight reduction of the AF group is considered during the design process to satisfy the effective focal length (EFL), back focal length (BFL), and front focal length (FFL) in the proposed optical system using Gaussian-bracket method.
The designed optical system can focus from infinity to a magnification of
We have designed an ultrawide-angle optical system for compact optical systems that are suitable for high-performance ophthalmology and dermatology applications.
Open accessResearch articleFirst published January, 2019pp. 143-151Heart rate variability (HRV) can reflect the relationship between heart rhythm and sleep structure.
In order to study the effect of support vector machine (SVM) on the results of automatic sleep staging and improve the effectiveness of heart rate variability (HRV) as a sleep structure biomarker, thereby realize long term and non-contact monitoring of sleep quality.
Two kinds of parameter optimization methods are applied to stage sleep experiments when the known SVM can be used for automatic sleep staging. By factor analysis of the time domain, frequency domain, and nonlinear dynamic characteristics of subjects’ HRV signals, the accuracy of the cross-validation method (K-CV) is used as the fitness function value in genetic algorithm (GA) and particle swarm optimization (PSO). Furthermore, GA and PSO are used to optimize the SVM parameters.
The results show that the accuracy rate of sleep stage is 64.44% when parameters are not optimized, the accuracy rate based on PSO is improved to 78.89% and the accuracy rate based on GA is improved to 84.44%.
Both optimization algorithms can improve the accuracy of SVM for sleep staging and better results based on GA in the experiment.
Open accessResearch articleFirst published January, 2019pp. 153-163Wet age-related macular degeneration (Wet AMD) has been treated clinically by intravitreal injection of bevacizumab, which is a kind of the anti-VEGF antibody drug. Nevertheless, because of the short half-life and frequent injections, the use of this treatment is limited.
To confirm whether mPEG-PLGA-BOX can be considered as a VEGF drug delivery system to inhibit retinal angiogenesis.
A thermo-responsive hydrogel of methoxy-poly (ethylene glycol)-block-poly (lactic-co-glycolic acid) (mPEG-PLGA-BOX) was synthesized. The thermo-responsive hydrogel mPEG-PLGA-BOX was able to have sol-gel phase transition upon stimulation by the body temperature with improved biocompatibility and biodegradation. The bevacizumab released from mPEG-PLGA-BOX inhibited RF/6A cells according to a JC-1 assay, which indicated that the released bevacizumab was active to be able to suppress the growth of new blood vessels. In an animal study, retinal laser photocoagulation was performed to induce angiogenesis in the eyes of Rex rabbits using an 810-mm laser.
The retina was penetrated when the laser power was more than 500 mW and the exposure time was more than 500 ms. New blood vessels were created at the 28th day after retinal laser photocoagulation. At this time, intravitreal 0.05-mL injections of mPEG-PLGA-BOX (bevacizumab) solution were administered. The bevacizumab released from mPEG-PLGA-BOX (bevacizumab) solution suppressed the angiogenesis. In an
Bevacizumab released from mPEG-PLGA-BOX (bevacizumab) solution suppressed angiogenesis, and mPEG-PLGA-BOX can be considered as a novel thermo-responsive hydrogel with potential as a gelling carrier for extended bevacizumab drug release to treat intraocular neovascular diseases.
Open accessResearch articleFirst published January, 2019pp. 165-173Assistant equipment for the visually impaired has a white cane. If the information in the three-dimensional space is transmitted by sound, the blind can draw a three-dimensional space.
This study developed “Visual System,” an ambulation aid/guide for the blind that transforms visual-spatial information into auditory information, and verified its utility. Unlike conventional systems, which are in essence simple collision-warning systems, Visual System helps the visually impaired to recreate their surroundings and to be cognizant of the location and proximity of obstacles.
Ten subjects with normal vision (mean age: 32.4 years; male-to-female ratio: 6 to 4) were selected for blind tests. The subjects were instructed to detect and avoid obstacles presented in various three-dimensional settings. Prior to the tests, experiments were conducted to determine the distance to each subject. Upon completion of Visual System-based detection training, obstacles were presented and tests conducted. For evaluation, the subjects’ vertical position detection, horizontal position detection, distance detection, and overall performance success were each evaluated.
The total performance scores ranged between 88 (lowest) and 100 (highest), with a mean score of 91.5.
The results indicate that Visual System as a product can assist the visually impaired in their daily functioning.
Open accessResearch articleFirst published January, 2019pp. 175-184Physical exercises have been shown to be a surprisingly effective strategy to take advantage of the brain’s natural capacity for plasticity, and prevent brain degeneration in mouse histological studies. In vivo magnetic resonance microscopy (MRM) provides highly resolved anatomical images and allows quantitative assessment of brain atrophy in the aged mouse model.
The aim of the present study was to investigate, through the effects of 10 weeks voluntary wheel running, the mouse’s brain atrophy.
Sixteen C57BL/6J mice, aged 21 months, were randomized to the exercise or sedentary group. Each mouse was scanned in a 7.0-T MRM scanner at two time points: 22 months old baseline and a follow-up three months later. Multi-atlas based brain segmentation approach was used to obtain volumes of 39 brain regions.
The results showed that mice in the exercise group had less brain atrophy compared with the mice in the sedentary group.
The results provide new insights into exercise induced brain plasticity in aged animals.
Open accessResearch articleFirst published January, 2019pp. 185-193For a protein to execute its function, ensuring its correct subcellular localization is essential. In addition to biological experiments, bioinformatics is widely used to predict and determine the subcellular localization of proteins. However, single-feature extraction methods cannot effectively handle the huge amount of data and multisite localization of proteins. Thus, we developed a pseudo amino acid composition (PseAAC) method and an entropy density technique to extract feature fusion information from subcellular multisite proteins.
Predicting multiplex protein subcellular localization and achieve high prediction accuracy.
To improve the efficiency of predicting multiplex protein subcellular localization, we used the multi-label k-nearest neighbors algorithm and assigned different weights to various attributes. The method was evaluated using several performance metrics with a dataset consisting of protein sequences with single-site and multisite subcellular localizations.
Evaluation experiments showed that the proposed method significantly improves the optimal overall accuracy rate of multiplex protein subcellular localization.
This method can help to more comprehensively predict protein subcellular localization toward better understanding protein function, thereby bridging the gap between theory and application toward improved identification and monitoring of drug targets.
Open accessResearch articleFirst published January, 2019pp. 195-204In orthodontics, the tooth movement is a biologic reaction to applied force systems, brackets, archwires, and periodontium tissue.
To investigate the effects of the various archwire characteristics like the friction coebetween bracket and archwire, the cross-section shape, and the cross-section dimension, on the displacement and the periodontal ligament (PDL) stresses of canine’s movement in a self-ligating treatment using the finite element (FE) analysis method.
Models of teeth and their supporting tissues, brackets and archwires were constructed. Ten kinds of archwires were used for the simulation.
Considering the translation movement, the maximum displacement, highest stress, and
The archwire characteristics (round archwire, rectangular archwire, cross-section area, and friction coefficient) exhibited different effects on the tooth translation, rotation, and inclination. Our results can assist in the improvement of the self-ligating orthodontic treatment.
Open accessResearch articleFirst published January, 2019pp. 205-215How to accurately predict the occurrence of contamination in the fermentation process of Chlortetracycline? How to prompt field operators to take effective measures in time? This is a difficult problem that the fermentation process of Chlortetracycline has not been solved well.
The aim of this paper is to effectively predict whether the fermentation process of Chlortetracycline is contaminated or not.
A Gaussian process regression soft sensor modeling method with real time integration learning is studied in depth by combining two local learning strategies, namely just-in-time learning (JITL) method and integrated learning method, and a multi-model weighted Gaussian process regression (MWGPR) soft sensor modeling method based on real-time integration learning is proposed in the paper. This soft sensing method was used to study the relationship between the viscosity of fermentation broth and the contamination in fermentation process. A soft-sensing model based on the viscosity of fermentation broth for predicting the signs of contamination is established.
The validity of this method is verified by field data. The experimental results demonstrate that the soft sensing model proposed in this paper can effectively determine whether the fermentation broth is infected by hybrid bacteria.
The method proposed in this paper is innovative and practical so that field operators can issue early warning and take effective measures.
Open accessResearch articleFirst published January, 2019pp. 217-227Face symmetrization has extensive applications in both medical and academic fields, such as facial disorder diagnosis. Human face possesses an important characteristic, which is as known as symmetry. However, in many scenarios, the perfect symmetry doesn’t exist in human faces, which yields a large number of studies around this topic. For example, facial palsy evaluation, facial beauty evaluation based on facial symmetry analysis, and many among others. Currently, there are still very limited researches dedicated for automatic facial symmetrization. Most of the existing studies only utilized their own implantations for facial symmetrization to assist their interdisciplinary academic researches. Limitations thus can be noticed in their methods, such as the requirements for manual interventions. Furthermore, most existing methods utilize facial landmark detection algorithms for automatic facial symmetrization. Though accuracies of the landmark detection algorithms are promising, the uncontrolled conditions in the facial images can still negatively impact the performance of the symmetrical face production. To this end, this paper presents a joint-loss enhanced deep generative network model for automatic facial symmetrization, which is achieved by a full facial image analysis. The joint-loss consists of a pair of adversarial losses and an identity loss. The adversarial losses try to make the generated symmetrical face as realistic as possible, while the identity loss helps to constrain the output to have the same identity of the person in the original input as much as possible. Rather than an end-to-end learning strategy, the proposed model is constructed by a multi-stage training process, which avoids the demand for a large size of the symmetrical face as training data. Experiments are conducted with comparisons with several existing methods based on some of the most popular facial landmark detection algorithms. Competitive results of the proposed method are demonstrated.
Open accessResearch articleFirst published January, 2019pp. 229-238Previous studies showed that compared with single-bundle (SB) precedures, double-bundle (DB) anterior cruciate ligament (ACL) reconstruction perform better.
To make assurance that distance of TT-TG may be altered along with ACL rupture and reconstruction.
Imaging study of 201 patients’s related cases by MRI and CT scans.
Compared with the intact knee’s overall mean TT-TG value, the mean overall pre/postoperative TT-TG values showed a significant difference. For SB reconstruction, the mean pre/postoperative TT-TG values were 15.67
The increased TT-TG value from a ruptured ACL was significantly restored after ACL reconstruction. The TT-TG value after SB reconstruction was still obviously larger than that of the intact knee. It showed no significant difference between the postoperative TT-TG of the DB group and intact knees. The original TT-TG values of the knees were much closer to restoration after DB reconstruction.
Open accessResearch articleFirst published January, 2019pp. 239-247The incidence of cancers has increased year by year and the early diagnosis for cancer is important to prevent cancers. Due to abnormal metabolism of tumor cells, the acidification of extracellular environment is an important feature for cancer cells. To achieve efficient and accurate pH measurement, this paper proposes a new detection method based on the fluorescence characteristics of CdSe quantum dots detection, which uses CdSe QDs with unique optical properties as sensitive substances for pH detection. PBS buffer (0.2 mol/L) with different pH has been used to simulate cell metabolites at different pH values and use 365 nm laser source to excite mixture liquid. The emitted light was detected by a fluorescence detection device. A mathematical model between fluorescence intensity and pH was finally obtained. The experimental results show the method show better effectiveness than other pH detection methods and has a high resolution of 0.037 within a pH range of 6.1–7.8 and a measurement resolution of 0.037 pH units. This method has high temperature stability and short testing time, which shows high potential for pH detection. This method has its superiority in all the testing methods. It exhibits a new way of generalizing to pH detection.
Open accessResearch articleFirst published January, 2019pp. 249-262The main obstacle encountered in microarray technology is how to mine the valuable information under the profiles and study the genes function.
Maximal information coefficient (MIC) is a novel, non-parametric statistic that has been successfully applied to genome-wide association studies and differentially gene and miRNA expression analysis. However, the data used in these applications are not gold standard but real data.
Therefore, this study attempts to test the feasibility of MIC for differentially expressed gene identification with simulation data.
Our experiments indicate that, MIC perfermance is better than Limma always, which is almost the same level of SAM, ROTS or DESeq2. However, the count of AUC
Compared to the existing methods, our experiments show that MIC is not only in the first tier in identifying differentially expressed genes and noise immunity, but also shows better robustness and stronger data/environment adaptability.
Open accessResearch articleFirst published January, 2019pp. 263-272Traditional cancer treatments such as surgery, radiation, and chemotherapy destroy both cancer and normal cells, which limit their clinical application. It is difficult to achieve the best results for any liver cancer patients using any single treatment method. Gene therapy for HCC demands non-invasive, efficient, targeted and safe gene transfection strategies.
In this study, a nonviral shRNA gene delivery system utilizing a combination of PEI, US, and NBs was developed for targeting survivin in liver Cancer.
The PEI-shRNA-NBs cumulated in the tumor tissue because of the EPR effect. By exposure to the US, micelles shRNA may be released from PEI-shRNA-NBs in tumor tissues and the shRNA then transmitted efficiently to cancer cells. Considerably enhanced therapeutic outcome was obtained with the gene silencing effect enhanced.
PEI-shRNA-NBs possess the potential to become promising tools intended for shRNA delivery.
Open accessResearch articleFirst published January, 2019pp. 273-285Cerebral edema is a common secondary disease after stroke. It is very important to realize real-time continuous monitoring of cerebral edema for stroke patients.
A non-contact magnetic induction phase shift (MIPS) detection system is used to monitor the change of global brain electrical conductivity during cerebral edema.
In order to verify the feasibility of this system monitoring, we carry out salt solution simulation experiments and healthy people breath holding experiments. As a comparison of later clinical experiments, 13 young healthy volunteers aged 22–35 are selected for this study to carry out a 10 minute/time monitoring experiment.
It is found that the MIPS values measured by the salt solution of edema and the salt solution of bleeding are significantly different. The results show that the MIPS value of healthy young people is in a stable state with an MIPS mean value of 1.106 (
We preliminarily verify that the system can be used for cerebral edema monitoring.
Open accessResearch articleFirst published January, 2019pp. 287-300Atrial fibrillation (AF) is the most common type of persistent arrhythmia. Early diagnosis and intervention of AF is essential to avert the further fatality. The technique of noninvasive electrical mapping, especially the body surface potential mapping (BSPM), has a more practical application in the study of predicting AF, when compared with the invasive electrical mapping methods such as the epicardial mapping and interventional catheter mapping. However, the prediction of AF with noninvasive signals has been inadequately studied. Thus, the aim of this paper was to analyze the properties of atrial dynamic system based on the noninvasive BSPM signals (BSPMs), using the recurrence complex network, and consequently to evaluate its role in predicting the recurrence of AF in clinical aspect.
Twelve patients with persistent AF were included in this study. Their preoperative and postoperative BSPMs were recorded. Initially, the preoperative BSPMs were transformed into the recurrence complex network to characterize the complexity property of the atria. Subsequently, the parameters of recurrence ratio (REC), determinism (DET), entropy of the diagonal structure distribution (ENTR), and laminarity (LAM) were calculated. Furthermore, the difference in the parameters in the four regions of the body and the difference obtained from the dominant frequency (DF) method were compared. Finally, the results obtained for the atrial dynamic system complexity from a 12-lead electrocardiogram (ECG) from the BSPMs were discussed.
Our study revealed that the patients whose REC is greater than an average threshold, and with a lower LAM presented a much higher possibility of AF recurrence, after the AF surgery.
The recurrence complex network is a useful and convenient way to evaluate the nonlinear properties of the BSPMs in patients with AF. It has good immunity to the lead position and has a potential role in the understanding of predicting the recurrence of AF.
Open accessResearch articleFirst published January, 2019pp. 301-306The human hematopoietic stem/progenitor cell 117 (HSPC117) protein is involved in many important biological processes.
This study was designed to identify the level of HSPC117 mRNA expression in 10 min pig tissue samples and HSPC117 subcellular localization in the PK15 cell line.
In this study, 10 tissue samples of min pigs were collected, and EGFP-HSPC117 vectors were constructed to express EGFP-HSPC117 fusion proteins in PK15 cells.
HSPC117 mRNA was expressed in all of the tissue samples, although the levels of expression in fat and lung tissues were significantly lower than in other tissues (
These results indicate that the HSPC117 gene is expressed in many min pig tissues. The HSPC117 protein was distributed throughout the cells during interphase, but was concentrated in the nuclear area in mitotic cells.
Open accessResearch articleFirst published January, 2019pp. 307-316To investigate the roles and underlying mechanism of exogenous H
A total of 40 SD rats were randomly divided into 4 groups: control group, STZ group, STZ
Comparing to control group, the collagen deposition of myocardial matrix remarkably increased in the STZ group, and almost all the proteins that are relative to myocardial fibrosis, inflammatory and signaling pathway show an overexpression, except for PPARG and NF-
The myocardial fibrosis in DM rats can be attenuated effectively by exogenous H
Open accessResearch articleFirst published January, 2019pp. 317-329Stroke is a leading cause of mortality and disability, which can be affected by people’s daily living habits.
To investigate the effects of main daily living habits (smoking, drinking, diet, vegetable and fruits consumption, and exercise) on stroke risk in patients and provide the scientific basis for the assessment of the risk factors, a novel risk analysis model of the stroke is proposed.
A data mining method using decision trees which adopted the optimized C4.5 algorithm is presented. It is able to deal with the unbalanced data problem of the classification. Meanwhile, the proposed method has been verified on a clinical dataset of 23,682 patients with 21 risk factors.
The overall accuracy and kappa coefficient for stroke risk classification has reached 84.88% and 0.7763, respectively. Through the generated knowledge rules, it demonstrates that the behavioral habits in daily life have an indirect effect on the risk of stroke. While, it has an obvious effect on stroke when hypertension, diabetes mellitus, hypercholesterolemia, and BMI risk factors exist. In addition, it was observed that the aforementioned five daily living habits have a decreased impact on the stroke.
It is anticipated that the proposed system could help in reducing the risk, mortality, and disability of stroke, and provide clinical decision support for the treatment of stroke.
Open accessResearch articleFirst published January, 2019pp. 331-343To explore the effect of gefitinib-coated balloon suppressive action on the excessive hyperplasia of intima after balloon injury of common carotid artery in rats and on the PI3K/AKT signal pathway.
MTT method and the expression of Bcl-2 and Caspase-3 proteins were detected
At the same time and concentration, Gefitinib suppressed the proliferation of smooth muscle cell more significantly than paclitaxel. Bcl-2 and Caspase-3 in vascular smooth muscle and endothelial cells (VSMC, EC) were significantly down-regulated and up-regulated after the cells were treated with gefitinib and paclitaxel. In gefitinib- and paclitaxel-coated balloon groups, significant up-regulations were found in the area of lumen. Furthermore, the expression of PCNA suggested that all coated balloons could suppress the excessive proliferation of smooth muscle cells in the hyperplastic intima compared with the control group. In gefitinib- and paclitaxel-coated balloon group, the expression of PI3K/AKT was significantly down-regulated. The use of drug-coated balloons mitigated the cell apoptosis in TUNEL. The expressions of MMP9, TGF
Gefitinib-coated balloons were able to suppress the excessive proliferation in the common carotid arterial intima of rats more effectively than the paclitaxel-coated ones. The underlying mechanism may cover the PI3K/AKT signal pathway.
Open accessResearch articleFirst published January, 2019pp. 345-356Most fall intervention studies attempted to improve the mobility, range of motion of upper and lower extremities, or all major muscle strengths. Yet, there has been little effort to identify movements or actions that may be mainly responsible for recovering from a slipping. It was imperative to link lower extremity kinematics in conjunction with the functional anatomy of lower extremity muscles during forward heel-slipping to identify what muscles should have been activated substantially if a person would have recovered from forward heel-slipping.
The present study investigated lower extremity movements, such as the ankle, knee, and hip rotations, which could contribute to falls from forward heel-slipping. Determining changes in positions of foot, shank, and thigh during slipping would provide information to develop the optimal training regimen or interventions that may be effective for improving a chance to recover from the postural disturbance.
Twenty healthy adults (24–68 years old) participated in this experiment. Among twenty participants, only eight participants’ data were analyzed in this study. The 3D position data were used to compute the sagittal foot, shank, and thigh angles and frontal thigh angle.
The study results indicated that, during the period of slipping, the angles of the segments of the slipping leg were different from that of the foot, shank, and thigh when walking ordinarily over the dry surface in the present study.
The characteristics or differences in the angular kinematics of lower extremity during unexpected slips in the present study demonstrate possible causes for slip-induced falls.
Open accessResearch articleFirst published January, 2019pp. 357-365Dexamethasone (DEX) is associated with many inflammation and metabolic diseases. We analyzed the effects of DEX on the expression of estrogen metabolism enzyme 17
Open accessResearch articleFirst published January, 2019pp. 367-381Traditional Chinese Medicine (TCM) multiple-acupoints stimulation is widely used to improve dysphagia among post-stroke patients. However, prior research in evidence-based acupuncture mostly focused on the treatment effects of single acupoint’s on dysphagia, while the evidence of optimal sequence of multiple-acupoints stimulation remains limited. In this paper, we developed an evaluation method of hybrid knowledge (deterministic knowledge and the experiential group decision knowledge) sequences based on segmentation mechanism of sub-sequence fragments, and then, we proposed a Monte Carlo Tree Search (MCTS) sequential decision-making method under the hybrid knowledge. Thereafter, we applied this proposed sequential decision-making approach to optimizing sequential decision-making schema of multiple-acupoints stimulation, to treat dysphagia among post-stroke patients. Finally, we verified the validity and the feasibility of this method by comparing it to other sequential decision-making search methods.
Open accessResearch articleFirst published January, 2019pp. 383-395An important part of the rehabilitation process using exoskeleton robots has been the creation of a friendly Human Robot Interaction (HRI) system.
In order to combine SEMG signal into the HRI system, a SEMG-angle model based on Hidden Markov Model (HMM) was put forward in this paper.
Feature extraction as a critical issue of signal preprocessing was handled by Principal Component Analysis (PCA) which realized signal data dimension reduction and solved the common problem of redundant features. A comparison study was given to show the different performance of various EMG-angle model separately based on HMM, Back Propagation (BP) neural network and Radial Basis Function (RBF) neural network.
The HMM modeling method which with lower calculation complexity can achieve a better modeling performance (average accuracy 93.063%) compared with BP neural network (average accuracy 88.180%) and RBF neural network (average accuracy 88.752%).
SEMG signals have some characteristic properties which is similar to a quasi-stationary filtered white noise stochastic process, the structure of HMMs makes it ideally suited for classification and modeling SEMG signals, and the results of this study show that it can achieve a better performance than the commonly used methods (BP and RBF).
Open accessResearch articleFirst published January, 2019pp. 397-406Current multispectral photoacoustic instruments must use large and separate combinational structures to obtain various biological tissue information for multispectral ranges.
The optical aberration generated from the multispectral photoacoustic systems may reduce the image quality of biological tissue because the improper structures for combining light of different wavelength cannot produce good optical ray convergence points. To prevent this, complex combined structures need to be considered at the design level for multispectral photoacoustic systems.
In place of an optical refracted lens system, reflective mirrors could be designed for optical systems. To verify our proposed idea, we assessed optical distortion performance using red, green, and blue light, and combined optical light sources to compare their chromatic aberration characteristics.
The high optical performance is realized regardless of the wavelength for a light source combined with multiple wavelengths, because our optical system was designed with only a reflective surface.
The designed optical system using a reflective mirror can provide multispectral optical sources (such as infrared, visible, and ultraviolet optical lights) with only one light ray path, without any chromatic aberrations.
Open accessResearch articleFirst published January, 2019pp. 407-424The current method to evaluate major depressive disorder (MDD) relies on subjective clinical interviews and self-questionnaires.
Autonomic imbalance in MDD patients is characterized using entropy measures of heart rate variability (HRV). A machine learning approach for screening depression based on the entropy is demonstrated.
The participants experience five experimental phases: baseline (BASE), stress task (MAT), stress task recovery (REC1), relaxation task (RLX), and relaxation task recovery (REC2). The four entropy indices, approximate entropy, sample entropy, fuzzy entropy, and Shannon entropy, are extracted for each phase, and a total of 20 features are used. A support vector machine classifier and recursive feature elimination are employed for classification.
The entropy features are lower in the MDD group; however, the disease does not have a significant effect. Experimental tasks significantly affect the features. The entropy did not recover during REC1. The differences in the entropy features between the two groups increased after MAT and showed the largest gap in REC2. We achieved 70% accuracy, 64% sensitivity, and 76% specificity with three optimal features during RLX and REC2.
Monitoring of HRV complexity changes when a subject experiences autonomic arousal and recovery can potentially facilitate objective depression recognition.
Open accessResearch articleFirst published January, 2019pp. 425-443Post-traumatic stress disorder (PTSD) is a chronic mental disorder caused by mental or psychological trauma after sudden events of a catastrophic or threatening nature. Synaptic plasticity is the core mechanism of PTSD and the main point of treatment of this disease.
Male Sprague Dawley rats were randomly divided into blank control (Ctrl), SPS (single-prolonged stress) model, SPS&S model (SPS and foot electric shock), SPS+EA (SPS plus electroacupuncture), and SPS&S+EA groups. Tranquilize Mind and Regulate Kidney (TMRK) electroacupuncture method was performed in each rat in the SPS+EA and SPS&S+EA groups, the treatment lasted for 20 minutes per day, simultaneously for 3 consecutive weeks. Behavioral evaluations, molecular tests, electron microscopy, electrophysiological testing were conducted following the treatment.
First, electro-acupuncture can significantly improve the PTSD-like symptoms. Second, electro-acupuncture can up-regulate the long-term potentiation (LTP) in hippocampus, repair the synaptic morphology and improve BDNF levels in amygdala and hippocampus. Third, electroacupuncture can significantly up-regulate SYN, GAP43, and PSD95 protein levels and mRNA expression in amygdala and hippocampus.
The effect of TMRK electro-acupuncture method on the regression of fear memory of PTSD rats may be through its repair of synaptic plasticity in amygdala and hippocampus.
Open accessResearch articleFirst published January, 2019pp. 445-454This paper describes the design and implementation of a dual-coil type electromagnetic actuator for implantable bone conduction hearing devices.
The structure of the proposed actuator was designed to generate maximum Lorentz force via the dual-coil method with a closed magnetic circuit. To satisfy the indications required by implantable bone conduction hearing devices, high output was generated within a specific frequency range using a vibrational membrane with a cantilever.
The structure of the membrane consists of a fixed ring, a circular plate, and two cantilevers connected symmetrically. Variable elements of the vibrational membrane affecting the actuator frequency characteristics were analyzed through mathematical modeling and finite element analysis, based on the analysis used to derive the optimum structure of the vibrational membrane. The components of the actuator were fabricated through chemical etching and computer numerical control process, and the bone conduction actuator was fabricated through the precision assembly process.
The output characteristics of the implemented actuator were measured using a laser Doppler vibrometer. As a result of measurement, the proposed actuator generated mechanical resonance at 1.2 kHz.
By comparing the measured results with the finite element analysis results, we confirmed the validity of the proposed actuator design.