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Search Results: 1 - 10 of 49670 matches for " Sheng-Chieh Huang "
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SDNN/RMSSD as a Surrogate for LF/HF: A Revised Investigation
Hui-Min Wang,Sheng-Chieh Huang
Modelling and Simulation in Engineering , 2012, DOI: 10.1155/2012/931943
Abstract: Thousands of papers involved in heart rate variability (HRV). However, little was known about one important measure of HRV, the root mean square of successive heartbeat interval differences (RMSSDs). Another fundamental measure SDNN indicates standard deviation of normal to normal R-R intervals, where R is the peak of a QRS complex (heartbeat). Compared with SDNN, RMSSD is a short-term variation of heart rate. Through a time-frequency transformation, the ratio of low- and high-frequency power LF/HF represents the sympatho-vagal balance of the autonomic nervous system (ANS). Some research claimed that SDNN/RMSSD was a good surrogate for LF/HF. However, only two special cases supported this hypothesis in the literature survey. The first happened in resting supine state and the other was a group of prefrontal cortex patients. Both of their Pearson correlation coefficients reached 0.90, a reasonable criterion. In our study, a 6-week experiment was performed with 32 healthy young Asian males. The Pearson correlation coefficients had a normal distribution with average values smaller than 0.6 for 3 and 5-minute epochs, respectively. Our findings suggest this surrogate aspect could remain as a hypothesis. 1. Introduction RMSSD, the root mean square differences of successive R-R (heartbeat) intervals, is a significant indicator for both atrial fibrillation (AF) and sudden unexplained death in epilepsy (SUDEP) [1, 2]. Beyond RMSSD, some other essential variables of heart rate variability (HRV) measures are SDNN, LF and HF. SDNN is the standard deviation of normal to normal R-R intervals. LF and HF represent power in low- and high-frequency ranges [3]. Previous research suggested that SDNN/RMSSD was a good surrogate of LF/HF for healthy subjects [4, 5]. Whether this statement is affirmative would be revised by analysis of cardiac measurements in this paper. Measurements of HRV include time domain, frequency domain methods, and so on. They are noninvasive, as the tools to recognize the relationship between the autonomic nervous system (ANS) and cardiovascular mortality [3]. Figure 1 shows a standard routine of electrocardiogram (ECG) signal processing [6]. Detection of heartbeats (QRS complexes) is the first step, where R is the peak of the complex. The time domain analysis (SDNN, RMSSD) reports the activity of the cardiac system. The frequency domain analysis (LF, HF) reflects sympathovagal balance of the ANS. These HRV variables can be calculated easily through a superlative software package [7]. As time went by, HRV yielded rich fruits in various applications
Musical Rhythms Affect Heart Rate Variability: Algorithm and Models
Hui-Min Wang,Sheng-Chieh Huang
Advances in Electrical Engineering , 2014, DOI: 10.1155/2014/851796
Abstract: There were a lot of psychological music experiments and models but there were few psychological rhythm experiments and models. There were a lot of physiological music experiments but there were few physiological music models. There were few physiological rhythm experiments but there was no physiological rhythm model. We proposed a physiological rhythm model to fill this gap. Twenty-two participants, 4 drum loops as stimuli, and electrocardiogram (ECG) were employed in this work. We designed an algorithm to map tempo, complexity, and energy into two heart rate variability (HRV) measures, the standard deviation of normal-to-normal heartbeats (SDNN) and the ratio of low- and high-frequency powers (LF/HF); these two measures form the physiological valence/arousal plane. There were four major findings. Initially, simple and loud rhythms enhanced arousal. Secondly, the removal of fast and loud rhythms decreased arousal. Thirdly, fast rhythms increased valence. Finally, the removal of fast and quiet rhythms increased valence. Our work extended the psychological model to the physiological model and deepened the musical model into the rhythmic model. Moreover, this model could be the rules of automatic music generating systems. 1. Introduction The relation of music to emotion has been studied for decades and the literature is fruitful [1]. There exist a lot of psychological models between music and emotion [2], but the physiological models between music and emotion are limited [3]. One of the physiological actions, heart rate variability (HRV), which is controlled by the autonomic nervous system (ANS), is tightly connected with emotions [4]. Previously, we had analyzed the relationship between musical rhythms and HRV [5] and built two heuristic models [6, 7]. In this paper, a systematic algorithm is proposed to construct new models. Musical emotions change with psychophysiological measures and musical features [8], whilst three basic questions are highlighted [9]: how do musical features evoke emotions; how do actions involved in musical emotions progress; and which actions and brain processes are involved in musical emotions. Basically, people feel what music expresses but need not be always; in a simple case, only 61% of 45 participants felt what they perceived [10]. More particularly, a stronger correlation is suggested by a recently developed theory that the aesthetic awe accompanies by being moved (cognitive), emotions (psychological), and thrills (physiological) in the same time [11]. The three associated levels of musical response should be analyzed
A ±6?ms-Accuracy, 0.68?mm2, and 2.21?μW QRS Detection ASIC
Sheng-Chieh Huang,Hui-Min Wang,Wei-Yu Chen
VLSI Design , 2012, DOI: 10.1155/2012/809393
Abstract: Healthcare issues arose from population aging. Meanwhile, electrocardiogram (ECG) is a powerful measurement tool. The first step of ECG is to detect QRS complexes. A state-of-the-art QRS detection algorithm was modified and implemented to an application-specific integrated circuit (ASIC). By the dedicated architecture design, the novel ASIC is proposed with 0.68?mm2 core area and 2.21?μW power consumption. It is the smallest QRS detection ASIC based on 0.18?μm technology. In addition, the sensitivity is 95.65% and the positive prediction of the ASIC is 99.36% based on the MIT/BIH arrhythmia database certification. 1. Introduction Many healthcare issues arose out of population aging [1] and experts hoped to monitor people’s health through various physiological sensors [2]. Electrocardiogram (ECG) is one of the physiological signals [3]. Since the milestone paper proposed in 1996, the study of ECG is still an ongoing hot research topic [4–7]. Some software (S/W) application for ECG analysis had been developed on personal computer (PC) [8]. Figure 1 shows a standard routine of ECG signal processing. The detection of heartbeats (QRS complexes) is the first step, while R is the peak of the complex and heart rate variability (HRV) is the standard deviation of time sequence (RR-intervals). The time domain analysis reports the activity of circulatory system and the frequency domain analysis reflects the sympathovagal balance of autonomic nervous system (ANS) [9–13]. In our previous works, this standard routine had been modified to MATLAB codes [14, 15] and the QRS detection algorithm had also been implemented in field programmable gate array (FPGA) [16]. Figure 1: The block diagram of the overall signal processing flow of ECG analysis. Beyond PC, mobile phone is another S/W solution [17, 18]. In the other way, the QRS detection algorithm can be found in hardware (H/W) implementations, such as ARM [19], DSP [20, 21], FPGA [22–24], or ASP [25]. For the purpose of long time use, an application-specific integrated circuit (ASIC) solution of real-time and very low-power consumption should be considered. Some previous chip designs were surveyed as the comparison targets [26–38]. We will give a detailed description for our design, which had been presented briefly in 2010 [39], in this paper. For the application, one [27] of above ECG chips had been embedded into a biomedical system already [40]. The remainder of this paper is structured as follows. In Section 2, the algorithm design is briefly described. In Section 3, we state the architecture design. In Section 4,
Numerical Simulation of Optically-Induced Dielectrophoresis Using a Voltage-Transformation-Ratio Model
Shih-Hsun Hung,Sheng-Chieh Huang,Gwo-Bin Lee
Sensors , 2013, DOI: 10.3390/s130201965
Abstract: Optically-induced dielectrophoresis (ODEP) has been extensively used for the manipulation and separation of cells, beads and micro-droplets in microfluidic devices. With this approach, non-uniform electric fields induced by light projected on a photoconductive layer can be used to generate attractive or repulsive forces on dielectric materials. Then, moving these light patterns can be used for the manipulation of particles in the microfluidic devices. This study reports on the results from numerical simulation of the ODEP platform using a new model based on a voltage transformation ratio, which takes the effective electrical voltage into consideration. Results showed that the numerical simulation was in reasonably agreement with experimental data for the manipulation of polystyrene beads and emulsion droplets, with a coefficient of variation less than 6.2% (n = 3). The proposed model can be applied to simulations of the ODEP force and may provide a reliable tool for estimating induced dielectrophoretic forces and electric fields, which is crucial for microfluidic applications.
Ritual Significance in Mycenaean Hairstyles
Hsu, Florence Sheng-chieh
Chronika , 2012,
Abstract: Although the frescoes excavated from Bronze Age sites on the Greek mainland provide evidence for female figures in the Mycenaean society, the hairstyles of these figures have not been studied in detail. As in many other ancient cultures, hairstyles were not only an exhibition of beauty and fashion, but they also represented certain age groups or a person’s social status. The Mycenaeans inherited many of their hairstyles from their Minoan predecessors, although differences existed as well. It is also possible there may have been a shift in meaning for seemingly similar looking hairstyles from the Minoan to the Mycenaean periods. Female figures, which compose most of the Mycenaean figures in frescoes known to date, are fine examples for discussing the artistic representation and potential significance of Mycenaean hairstyles. By comparing with Minoan hairstyles, discussions of Mycenaean examples lead to conclusions in the relationship between hairstyles and ritual activities in the Mycenaean society.
10 Gb/s Optical Interconnection on Flexible Optical Waveguide in Electronic Printed Circuit Board  [PDF]
Shih-Hsiang Hsu, Chih-Yuan Tsou, Chih-Ming Wang, Sheng-Chieh Tseng
Optics and Photonics Journal (OPJ) , 2013, DOI: 10.4236/opj.2013.32B059
Abstract:

In this paper, we proposed 10 Gb/s transmission using 4-channel polymer waveguides on the optical electronic printed circuit board. It was simulated by the ray tracing method for tolerance study of optical interconnection and fabrication. In order for easy fabrication and high position accuracy, the polymer waveguides were forming silver coated 45° reflective mirrors by dicing method and e-beam deposition for 90° light beam turning. The coupling loss was demonstrated in different polishing grit sizes. The optical interconnection in board-embed 4-channel flexible waveguides was demonstrated with a low propagation loss of 0.1 dB/cm and a clear eye diagram at 2.5 Gb/s data rate per channel.

Unique Tail Appendages of Marine Bacteriophages  [PDF]
Yurii G. Kuznetsov, Sheng-Chieh Chang, Arielle Credaroli, Alexander McPherson
Advances in Microbiology (AiM) , 2013, DOI: 10.4236/aim.2013.36A007
Abstract: The objective was to visualize a variety of marine bacteriophage and identify unique structural features that set them apart from terrestrial phages. Phages were plaque isolated and characterized using atomic force microscopy. Bacteriophage infecting cyanobacteria synechococcus that exhibits a novel structural feature not previously reported for any other phages were observed. These cyanophages have up to four, 450 nm long, multi-stranded, complex helical fibers that emanate from either the base plate and/or the collar of the phage particle, origins of shorter fibers on well-studied phages such as T4. The flexible fibers terminate at their distal ends in multiple bulbs of diameter 30 nm composed of 20 to 30 closely associated proteins. Bulbs form one of two distinctive patterns, or tassels. Most commonly, the arrangement is a 3 + 1 pattern of three consecutive bulbs at the very end with a forth lying upstream, separated from the terminal three by a gap of 135 nm. In other populations the fibers terminate in 5 consecutive bulbs. It is proposed that the novel appendages may be involved in host cell searching and recognition in a marine environment.
A Real World Report on Intravenous High-Dose and Non-High-Dose Proton-Pump Inhibitors Therapy in Patients with Endoscopically Treated High-Risk Peptic Ulcer Bleeding
Lung-Sheng Lu,Sheng-Chieh Lin,Chung-Mou Kuo,Wei-Chen Tai,Po-Lin Tseng,Kuo-Chin Chang,Chung-Huang Kuo,Seng-Kee Chuah
Gastroenterology Research and Practice , 2012, DOI: 10.1155/2012/858612
Abstract: Background and Study Aims. The optimal dose of intravenous proton-pump inhibitor (PPI) therapy for the prevention of peptic ulcer (PU) rebleeding remains controversial. This study aimed to understand the real world experiences in prescribing high-dose PPI and non-high-dose PPI for preventing rebleeding after endoscopic treatment of high-risk PU. Patients and Methods. A total of 220 subjects who received high-dose and non-high-dose pantoprazole for confirmed acute PU bleeding that were successfully treated endoscopically were enrolled. They were divided into rebleeding ( ) and non-rebleeding groups ( ). Randomized matching of the treatment-control group was performed. Patients were randomly selected for non-high-dose and high-dose PPI groups ( in each group). Results. Univariate analysis showed, significant variables related to rebleeding were female, higher creatinine levels, and higher Rockall scores (≧6). Before case-control matching, the high-dose PPI group had higher creatinine level, higher percentage of shock at presentation, and higher Rockall scores. After randomized treatment-control matching, no statistical differences were observed for rebleeding rates between the high-dose and non-high-dose groups after case-control matching. Conclusion. This study suggests that intravenous high-dose pantoprazole may not be superior to non-high-dose regimen in reducing rebleeding in high-risk peptic ulcer bleeding after successful endoscopic therapy. 1. Introduction Patients with high-risk stigmata on endoscopic examination for acute upper gastrointestinal bleeding are at increased risk of recurrent bleeding [1]. Endoscopic hemostasis and continuous infusion intravenous high-dose proton-pump-inhibitor (PPI) have been proven to reduce recurrent bleeding, need for surgery, and length of hospital stay [2, 3]. Furthermore, the recently updated Vienna consensus states that intravenous high-dose PPI therapy after successful endoscopic hemostasis decreases both peptic ulcer (PU) rebleeding and mortality in patients with high-risk stigmata [4]. Despite these recent advances in the pharmacological and endoscopic treatment of acute nonvariceal upper gastrointestinal hemorrhage, the associated mortality remains high at 10% to 14% [5]. Theoretically, inhibiting gastric acid and raising the intragastric pH to 6 or more and maintaining it at that level may promote clot stability, thus decrease the likelihood of rebleeding. This is based on experimental data showing that gastric acid impairs clot formation, promotes platelet disaggregation, and favors fibrinolysis [6]. The
Dynamic Contrast-Enhanced MR Imaging Predicts Local Control in Oropharyngeal or Hypopharyngeal Squamous Cell Carcinoma Treated with Chemoradiotherapy
Shu-Hang Ng, Chien-Yu Lin, Sheng-Chieh Chan, Tzu-Chen Yen, Chun-Ta Liao, Joseph Tung-Chieh Chang, Sheung-Fat Ko, Hung-Ming Wang, Shiang-Fu Huang, Yu-Chun Lin, Jiun-Jie Wang
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0072230
Abstract: The role of pretreatment dynamic contrast-enhanced perfusion MR imaging (DCE-PWI) and diffusion-weighted MR imaging (DWI) in predicting the treatment response of oropharyngeal or hypopharyngeal squamous cell carcinoma (OHSCC) to chemoradiation remains unclear. We prospectively investigated the ability of pharmacokinetic parameters derived from pretreatment DCE-PWI and DWI to predict the local control of OHSCC patients treated with chemoradiation. Between August, 2010 and March, 2012, patients with untreated OHSCC scheduled for chemoradiation were eligible for this prospective study. DCE-PWI and DWI were performed in addition to conventional MRI. The relationship of local control with the following clinical and imaging variables was analyzed: the hemoglobin level, T-stage, tumor location, gross tumor volume, maximum standardized uptake value, metabolic tumor volume and total lesion glycolysis on FDG PET/CT, transfer constant (Ktrans), volume of blood plasma and volume of extracellular extravascular space on DCE-PWI, and apparent diffusion coefficient on DWI of the primary tumor. The patients were also divided into a local control group and a local failure group, and their clinical and imaging parameters were compared. There were 58 patients (29 with oropharynx squamous cell carcinoma [SCC] and 29 with hypopharynx SCC) with successful pretreatment DCE-PWI and DWI available for analysis. After a median follow-up of 18.2 months, 17 (29.3%) participants had local failure, whereas the remaining 41 patients achieved local control. Univariate analysis revealed that only the Ktrans value was significantly associated with local control (P = 0.03). When the local control and local failure groups were compared, significant differences were observed in Ktrans and the tumor location (P = 0.01 and P = 0.04, respectively). In the multivariable analysis, only Ktrans was statistically significant (P = 0.04). Our results suggest that pretreatment Ktrans may help predict the local control in OHSCC patients treated with chemoradiation.
Elevated BCRP/ABCG2 Expression Confers Acquired Resistance to Gefitinib in Wild-Type EGFR-Expressing Cells
Yun-Ju Chen, Wei-Chien Huang, Ya-Ling Wei, Sheng-Chieh Hsu, Ping Yuan, Heather Y. Lin, Ignacio I. Wistuba, J. Jack Lee, Chia-Jui Yen, Wu-Chou Su, Kwang-Yu Chang, Wen-Chang Chang, Tse-Chuan Chou, Chao-Kai Chou, Chang-Hai Tsai, Mien-Chie Hung
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0021428
Abstract: Background The sensitivity of non-small cell lung cancer (NSCLC) patients to EGFR tyrosine kinase inhibitors (TKIs) is strongly associated with activating EGFR mutations. Although not as sensitive as patients harboring these mutations, some patients with wild-type EGFR (wtEGFR) remain responsive to EGFR TKIs, suggesting that the existence of unexplored mechanisms renders most of wtEGFR-expressing cancer cells insensitive. Methodology/Principal Findings Here, we show that acquired resistance of wtEGFR-expressing cancer cells to an EGFR TKI, gefitinib, is associated with elevated expression of breast cancer resistance protein (BCRP/ABCG2), which in turn leads to gefitinib efflux from cells. In addition, BCRP/ABCG2 expression correlates with poor response to gefitinib in both cancer cell lines and lung cancer patients with wtEGFR. Co-treatment with BCRP/ABCG2 inhibitors enhanced the anti-tumor activity of gefitinib. Conclusions/Significance Thus, BCRP/ABCG2 expression may be a predictor for poor efficacy of gefitinib treatment, and targeting BCRP/ABCG2 may broaden the use of gefitinib in patients with wtEGFR.
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