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The Double-Barreled cannon stent-graft Aortic Repair (DoBAR) strategy is a specific method for fixing extremely dilated aortic landing-zone issue. Its clinical validation and application may be examined using computational schemes. Three assumed conditions: the single stent-graft, the longitudinal direction (LD)-type DoBAR, and the sagittal direction (SD)-type DoBAR models were examined by computational fluid dynamics (CFD) simulations. Two specific points in one cardiac cycle were plotted. The non-dimensional frequency parameters were calculated to evaluate the flow field stabilities. The primary axial flow skewed from inner to outer aortic portion after passing through the aortic arch at peak forward-flow time (PFFT) and formed the swing signature at peak reverse-flow time (PRFT). The secondary flow developed as counter-rotating vortices of this model. In LD-type, the septum of antero- posterior chambers separated the primary flow to form two individual axial flows, the morphology resembled as the single model at PFFT. In SD-type, the septum of outer-inner chambers divided the flow pathway into two layers, and then weakened the reversed flow strength at PRFT. The septum of the DoBAR limited the development of secondary flow and the swing pattern disappeared in both types. The Strouhal and Wormersly numbers showed the flow pulsatility intensity decreased with steadier flow in both DoBAR models. The Dean numbers disclose the SD-type had weaker axial velocity and weaker secondary flow

Bharath and Shumway (2008) provide evidence that shows that it is the functional form of Merton’s (1974) distance to default (DD) model that makes it useful and important for predicting defaults. In this paper, we investigate whether the default predictability of the Merton DD model would be affected by taking investors’ ambiguity aversion into consideration. The Cox proportional hazard model is used to compare the forecasting power of Bharath and Shumway’s naive model, which retains the functional form of the Merton DD model and computes the default probability in a naive way, with our new model, which treats investors’ ambiguity aversion as additional information. We provide evidence to show that our new model performs better than Bharath and Shumway’s naive model. In addition, our empirical results show that the statistical significance of Bharath and Shumway’s naive default probability is retained in the credit default swap (CDS) spread regressions, though the sign of the coefficient is changed. However, both the sign and the statistical significance of our model are retained in the CDS spread regressions.

Chlorine added during wastewater disinfection may be consumed through reactions with chlorine-demanding chemical species. In this study, a mechanistically based kinetic model for chlorine demand in the presence of ammonia was developed and validated with laboratory studies on ammonia-nitrite systems, and then applied to breakpoint curves obtained with wastewater samples. The model is a modification of kinetic models for chlorine-ammonia systems to include hypochlorous acid-demand and monochloramine-demand reactions. The model accurately describes both laboratory-generated breakpoint curves with added nitrite and literature data. In a plant thought to be undergoing partial nitrification, breakpoint curves were consistent with high chlorine demand (i.e., small initial slopes and large doses to achieve the total chlorine maximum and breakpoint). A simplified kinetic model was also developed. Chlorine demand calculated from the simplified model was similar to chlorine demand from plant data. The simplified model was used to generate operating guidelines to calculate chlorine doses needed to overcome demand from nitrite or other sources.

This paper proposes a rule-based decision-making diagnosis system to evaluate arteriovenous shunt (AVS) stenosis for long-term hemodialysis treatment of patients using fuzzy petri nets (FPNs). AVS stenoses are often associated with blood sounds, resulting from turbulent flow over the narrowed blood vessel. Phonoangiography provides a noninvasive technique to monitor the sounds of the AVS. Since the power spectra changes in frequency and amplitude with the degree of AVS stenosis, it is difficult to make a human-made decision to judge the degree using a combination of those variances. The Burg autoregressive (AR) method is used to estimate the frequency spectra of a phonoangiographic signal and identify the characteristic frequencies. A rule-based decision-making method, FPNs, is designed as a decision-making system to evaluate the degree of stenosis (DOS) in routine examinations. For 42 long-term follow-up patients, the examination results show the proposed diagnosis system has greater efficiency in evaluating AVS stenosis.

The implantable stimulator for epileptic seizure suppression with loading impedance adaptability was proposed in this work. The stimulator consisted of the high voltage generator, output driver, adaptor, and switches, can constantly provide the required 40-μA stimulus currents, as the loading impedance varied within 10 kΩ -300 kΩ. The performances of this design have been successfully verified in silicon chip fabricated by a 0.35- μm 3.3-V/24-V CMOS process. The power consumption of this work was only 1.1 mW-1.4 mW. The animal test results with the fabricated chip of proposed design have successfully verified in the Long-Evans rats with epileptic seizures.

This paper proposes the interaction physical-activity housekeeper (IPAH) in physical activity for silver-haired citizen. It consists of the pulse sound receiver (PSR), ergometer, bluetooth module, and smart phone. The silver-haired citizen has various physical activity levels can enhance the quality of life, cardiovascular fitness, and strength of lower limbs. Therefore, it is recommended that the elderly people should increase physical activity level and cardiovascular fitness. The portable bio-signal monitors are used to monitor the physical activity status, including heartbeat (heart rate) and muscular strength. The goals of research can become commercial sport products for silver-haired citizen.

This paper proposed the signal processing method for evaluation of arteriovenous shunt (AVS) stenosis in hemodialysis patients. AV shunts are surgically created pathological or physiological fistulas serving as access routes for end-stage renal disease (ESRD) patients. The distinct and periodic bruit of vascular shunts is clearly audible over the access routes. Thus, a bruit spectral analysis could be considered a valuable noninvasive method for quantifying the severity of vessel stenosis. This study comprised the Burg method and fractional order chaos system (FOCS). We utilized the Burg method to estimate the characteristic frequency of bruit and a FOCS to monitor the differing frequency spectra between the normal condition and AV access stenosis. This study recruited 50 years old female and received the regular follow-up analysis for her forearm loop AVS function during 5 months. From these results, we observed that the function of AVS can be estimated by the butterfly patterns. This received the regular follow-up analysis for her forearm loop AVS function.

Aorta provides as the passageway for blood in supplying nutrients to human body is the vital organ for human. Whenever, aorta has pathologic change might be life threatening emergency due to massive blood loss. The most common encountering conditions are aortic aneurysm rupture and acute aortic dissection and the most lesions sites are located near the aortic arch. The etiology for these pathologic changes is closely related to the intra-aortic high-speed, high-pressure pulsatile blood flow. Study the blood flow and the hemodynamic change might help us to understand the pathologic change and further prevent its happening. Therefore, we tried to use the computational fluid dynamics methodology to understand the flow dynamics in the aorta crossing the aortic arch. The axial velocity profiles and secondary flow vectors were plotted at two time points during systolic phase. The primary axial flow velocity skewed from medial side of aorta to lateral side after pass through aortic arch and the secondary flow developed as counter-rotating vortices in the middle plane.

Increasing studies have implicated the thalamus in schizophrenia, supporting the view that this structure has an important role in this disorder. Given that extensive reciprocal connections exist between the thalamus and the cerebral cortex, it is believed that disruptions of the thalamo-cortical connections may underlie the multiplicity of schizophrenic symptoms. Therefore, assessing the relationship between the thalamus and the neocortex may provide new insights into the pathophysiology of schizophrenia. We analyzed magnetic resonance images from a sample of 101 schizophrenic patients and 101 healthy controls. By assessing the correlation between the thalamic volume and cortical thickness at each vertex on the cortical surface, a thalamo-cortical network was obtained for each group. We compared the patterns of thalamo-cortical connectivity between the two groups. Compared with healthy controls, less distributed cortical regions were identified in the thalamocortical network in patients with schizophrenia. Vertex-wise comparison revealed decreased thalamo-cortical connectivity in bilateral inferior frontal gyrus, the left superior temporal gyrus and the right parieto-occipital region in schizophrenia. The observed disruptions in thalamo-cortical connectivity might be the substrate underlying the wide range of schizophrenic symptoms and provide further evidence to support the notion of schizophrenia as a disorder of brain dysconnectivity. (C) 2014 Elsevier B. V. All rights reserved.

An implantable stimulator for epileptic seizure suppression with loading impedance adaptability [1] is demonstrated in the Conference. The stimulator consisted of a high voltage generator, an output driver, an adaptor, and switches, has been integrated in a silicon chip. The fabricated chip of the stimulator has been applied to a closed-loop epileptic seizure monitoring and controlling system [2] for animal test. The measurement setup with the equipments is shown in Fig. 1. The implantable stimulator with Long-Evans rat is shown in Fig. 2. All these experimental procedures have been reviewed and approved by Institutional Animal Care and Use Committee of National Cheng Kung University, Taiwan. The implantable stimulator to suppress the epileptic seizure of the Long-Evans rat will be demonstrated in the Conference. The electroencephalography (EEG) signals of the Long-Evans rat without and with applying the stimulation is presented in the Conference, as shown in Fig. 3. In Fig. 3(a), the epileptic discharges are observed during 3.5~12 s. When the seizure controller is applied in Fig. 3(b), the seizure is detected during 3.5~5.5 s. Upon the detection of the seizure, the intensive and rapidly brain activities are suppressed by the stimulation.

This paper proposed the signal processing method for evaluation of arteriovenous shunt (AVS) stenosis in hemodialysis patients. AV shunts are surgically created pathological-physiological fistulas serving as access routes for end-stage renal disease (ESRD) patients. The distinct and periodic bruit of vascular shunts is clearly audible over the access routes. Thus, a bruit spectral analysis could be considered a valuable noninvasive method for quantifying the severity of vessel stenosis. This study collected phonoangiographic data from thirty AV shunts obtained from the electronic stethoscope during the pre- and post-percutaneous transluminal angioplasty (PTA) periods. An autoregressive (AR) model was applied to scientifically analyze the phonoangiographic signals. The AR model and the filter order of eight were chosen to estimate the characteristic frequency of the bruit. The AR model results obtained from the analysis of the phonoangiographic data under the pre-PTA and post-PTA conditions show significant changes in frequency and magnitude. These findings could serve as a noninvasive strategy for early detection of stenotic lesions.

To detect the early developmental stages of arteriovenous access (AVA) stenosis in hemodialysis patients, this study explored a stenosis detector based on the Burg method and the fractional-order chaos system (FOCS). The bruit developed by the blood flowing through AVA can be a viable noninvasive strategy for monitoring AVA functions. We used the Burg method of the autoregressive model to estimate the frequency spectra of phonographic signals recorded by an electronic stethoscope in patients’ AVAs and to identify the spectral peaks in the region of 25–800 Hz. The frequency spectra differed significantly between normal and stenosis statuses in AVA. We found that the frequency and amplitude in power spectra analysis varied in accordance with the severity of AVA stenosis. However, the correlation of these parameters for classifying the degree of stenosis is limited when only using the Burg method. Therefore, we used an FOCS to monitor the differing frequency spectra between the normal condition and AVA stenosis. The variances of these two conditions were dynamic errors that were the coupling variables that tracked the responses between the master system and the slave system. A total of 42 patients who had received percutaneous transluminal angioplasty (PTA) for their failing AVAs was recruited for this study. In this study, the dynamic error, Index Ψ, was used to calculate the frequency spectrum redistribution in patients undergoing PTA. In addition, ΔImp was the index used to evaluate improvements in the luminal diameter between pre- and post-PTA. Therefore, we used linear regression to model the relationship between ΔImp and Index Ψ. The findings indicate that the proposed method has enhanced efficiency, especially in the venous anastomosis (V-site). The FOCS is a novel and simple algorithm for analyzing the residual AVA stenosis of PTA treatment.

The capacity allocation planning and expansion policy problem in the thin film transistor-liquid crystal display (TFT-LCD) industry is presented in this paper. The capacity allocation and expansion decisions gradually have become a challenging issue. Since the TFT Array stage is the bottleneck of this production network, the research objective is to simultaneously seek an optimal capacity allocation plan and expansion policy in the single-stage, multi-generation and multi-site structures. Capacity allocation decides on profitable product mixes and allocated production quantities of each product group at each production site. Capacity expansion is concerned with determining the timing, types, and sizes of capacity investments, especially in the acquisition of auxiliary tools. This paper proposes a mixed integer linear programming (MILP) to formulate the capacity allocation and expansion model, which considers many practical characteristics and constraints of TFT-LCD manufacturing, such as production capability constraint, multiple capacity types, economic cutting ratio, capacity expansion capability constraint, and high capacity expansion costs.

The novel implantable stimulus driver for epileptic seizure suppression with low power design and adaptive loading consideration was proposed in this work. The stimulus driver consisted of the output stage, charge pump system, and adaptor can constantly provide 40-μA output stimulus currents, as the electrode impedance varies within 10∼300 kΩ. The performances of this design have been successfully verified in a silicon chip fabricated by a 0.35-μm 3.3-V/24-V CMOS process. The power consumption of this work was only 1.1∼1.4 mW. The proposed stimulus driver has been integrated into closed-loop epileptic seizure monitoring and controlling system for animal test.

A 24-year-old man developed psychosis after improvement of epilepsy with vagus nerve stimulation treatment. He had a similar response when seizures were controlled by anticonvulsion agents. Psychosis was relieved with withdrawal of antiseizure treatment, but seizures then recurred.

The novel design with the adaptability prevents from unexpected stimulus current for medical safety, since the safety is the prime concern for human use. The prototype of the stimulus driver circuit for micro-stimulator used in implantable device is presented in this paper. For epilepsy control, the target of the driver is to output 30-µA stimulus currents, as the tissue impedance varies within 20∼200 kΩ. The driver composed of the output stage, adaptor, and control block, has been integrated in a chip. Fabricated in a 0.35-µm 3.3-V/24-V CMOS process, the performances of this novel design have been confirmed. The averaged power consumption of the driver was only 0.24∼0.56 mW under 800-Hz stimulation rate.

To analyze the pathological and clinical features of IgA nephropathy (IgAN) in west Guangdong province.The pathological type and clinical features of 120 patients with IgAN were retrospectively analyzed.Mesangial proliferative glomerulonephritis and focal segmental glomerulosclerosis were the most frequent features of IgAN. IgM deposit could be found in half of the IgAN patients, especially in the IgAN patients with focal segmental glomerulosclerosis.The incidence of IgAN may vary between different regions. Clinically, misdiagnosis of other renal diseases as IgAN may often occur. The nature and severity of glomerular immunoglobulin deposition can be related to the pathogenesis and progression of IgAN.

This study aimed to compare the kinematics and kinetics during the landing of hop-jump and step-close-jump movements in order to provide further inferring that the potential risk of ACL injuries. Eleven elite male volleyball players were recruited to perform hop-jump and step-close-jump tasks. Lower extremity kinematics and ground reaction forces during landing in stop-jump tasks were recorded. Lower extremity kinetics was calculated by using an inverse dynamic process. Step-close-jump tasks demonstrated smaller peak proximal tibia anterior shear forces during the landing phase. In step-close-jump tasks, increasing hip joint angular velocity during initial foot-ground contact decreased peak posterior ground reaction force during the landing phase, which theoretically could reduce the risk of ACL injury. Key pointsThe different landing techniques required for these two stop-jump tasks do not necessarily affect the jump height.Hop-jump decreased the hip joint angular velocity at initial foot contact with ground, which could lead to an increasing peak posterior GRF during the landing phase.Hop-jump decreased hip and knee joint angular flexion displacement during the landing, which could increase the peak vertical loading rate during the landing phase.

RILP (Rab7-interacting lysosomal protein) is a key regulator for late endosomal/lysosomal trafficking, and probably a tumor suppressor in prostate cancer. However, the role of RILP in other cancers and the underlying mechanism for RILP in regulating the invasion of cancer cells remain to be investigated. In this study, we showed that overexpression of RILP in breast cancer cells inhibits the migration and invasion, whereas the depletion of RILP by RNAi-mediated knockdown promotes the migration and invasion. We identified RalGDS (Ral guanine nucleotide dissociation stimulator) as a novel interacting partner for RILP, and truncation analysis revealed the N-terminal region of RILP is responsible for interacting with the guanine nucleotide exchange factor (GEF) domain of RalGDS. Immunofluorescence microscopy revealed that RalGDS can be recruited to the late endosomal compartments by RILP. Further investigations indicated that the overexpression of RILP inhibits the activity of RalA, a downstream target of RalGDS. Our data suggest that RILP suppresses the invasion of breast cancer cells by interacting with RalGDS to inhibit its GEF activity for RalA.

This paper proposes a signal processing method for the evaluation of arteriovenous (AV) shunt stenosis in hemodialysis patients. AV shunts are surgically created pathological fistulas that serve as access routes for hemodialysis. The distinct and periodic bruit of the vascular shunts is clearly audible over the access routes. Thus, a bruit spectral analysis can be a valuable noninvasive method for quantifying the severity of vascular stenosis. This study collected phonoangiographic data from thirty AV shunts obtained from an electronic stethoscope during pre- and post-percutaneous transluminal angioplasty (PTA) periods. An autoregressive (AR) model was applied to analyze the phonoangiographic signals. The AR model and a filter order of eight were chosen to estimate the characteristic frequency of the bruit. AR model results obtained from the analysis of the phonoangiographic data under the pre- and post-PTA conditions show significant changes in frequency and magnitude. Seven patients were enrolled for periodical follow-up analysis for AV shunts. The Burg AR model is used to find the characteristic frequency of phonoangiographic signals. Therefore, the variation of frequency and amplitude in power spectra analysis showed strong correlation with the severity of AV shunt stenosis.

A stimulus driver circuit for a micro-stimulator used in an implantable device is presented in this paper. For epileptic seizure control, the target of the driver was to output 30 μA stimulus currents when the electrode impedance varied between 20 and 200 k� . The driver, which consisted of the output stage, control block and adaptor, was integrated in a single chip. The averaged power consumption of the stimulus driver was 0.24–0.56 mW at 800 Hz stimulation rate. Fabricated in a 0.35 μ m3 .3 V/24 V CMOS process and applied to a closed-loop epileptic seizure monitoring and controlling system, the proposed design has been successfully verified in the experimental results of Long-Evans rats with epileptic seizures. (Some figures in this article are in colour only in the electronic version)

A copper-doped silica (Cu-SiO2) film of 50 nm thickness was prepared by cosputter deposition of Cu and SiO2 targets. A metal–oxide–metal (MOM) cell comprising a Cu-SiO2 layer sandwiched between a Cu top electrode and a Pt or Al bottom electrode was utilized to characterize resistive switching behavior. Both cells exhibited bipolar switching behavior. Electric conduction of the cell in the high-resistance state prepared using the Pt bottom electrode followed the space-charge-limited-current mechanism, whereas the cell prepared using the Al bottom electrode exhibited Schottky emission. An intermediate oxide layer was observed and attributed to the Schottky emission in the cell prepared using Al bottom electrode.

summary Objective: Repairing articular cartilage is clinically challenging. We investigated a simple, effective and clinically feasible cell-based therapeutic approach using a poly(lactide-co-glycolide) (PLGA) scaffold seeded with autologous endothelial progenitor cells (EPC) to repair a full-thickness osteochondral defect in rabbits using a one-step surgery. Methods: EPC obtained by purifying a small amount of peripheral blood from rabbits were seeded into a highly porous, biocompatible PLGA scaffold, namely, EPC-PLGA, and implanted into the osteochondral defect in the medial femoral condyle. Twenty two rabbits were randomized into one of three groups: the empty defect group (ED), the PLGA-only group or the EPC-PLGA group. The defect sites were evaluated 4 and 12 weeks after implantation. Results: At the end of testing, only the EPC-PLGA group showed the development of new cartilage tissue with a smooth, transparent and integrated articular surface. Moreover, histological analysis showed obvious differences in cartilage regeneration. At week 4, the EPC-PLGA group showed considerably higher TGF- b2 and TGF-b3 expression, a greater amount of synthesized glycosaminoglycan (GAG) content, and a higher degree of osteochondral angiogenesis in repaired tissues. At week 12, the EPC-PLGA group showed enhanced hyaline cartilage regeneration with a normal columnar chondrocyte arrangement, higher SOX9 expression, and greater GAG and collagen type II (COLII) content. Moreover, the EPCPLGA group showed organized osteochondral integration, the formation of vessel-rich tubercular bone and significantly higher bone volume per tissue volume and trabecular thickness (Tb.Th). Conclusion: The present EPC-PLGA cell delivery system generates a suitable in situ microenvironment for osteochondral regeneration without the supplement of exogenous growth factors.