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To evaluate the long-term efficacy of Coflex dynamic stabilization device in the treatment of lumbar spinal stenosis.The clinical and imaging data of 73 patients undergoing Coflex dynamic stabilization surgery from July 2008 to June 2012 were retrospectively analyzed. All patients had a minimum of 8 years of follow-up. Clinical data were used to assess the clinical efficacy, and radiographic parameters were measured for evaluation of ASD.56 Patients were followed up for 107.6 ± 13.3 months. The visual analogue scale of pain (VAS), Owestry disability index (ODI) and Japanese Orthopedic Association Scores (JOA) improved significantly after surgery. At 6 months after surgery and the last follow-up, lumbar range of motion (ROM) was significantly lower than that before surgery (P 0.001). ROM was slightly increased at the last follow-up compared with that 6 months after operation (P 0.05). ROM of adjacent segments increased at 6 months and at the last follow-up compared with that before surgery (P 0.05). At 6 months after surgery, intervertebral space height (ISH) and intervertebral foramen height (IFH) of implanted segment was significantly higher than that before surgery (P 0.05). At the last follow-up, there was a decrease in ISH and IFH (P 0.05). During the follow-up period, a total of 11 patients (19.6%) experienced complications and 6 patients (10.7%) underwent secondary surgery.Coflex interspinous process dynamic stabilization is effective in the long-term treatment of lumbar spinal stenosis, the ISH and IFH of implanted segment could be increased in a short period of time.

To evaluate the value of renal diffusion kurtosis imaging (DKI) in the diagnosis of early diabetic nephropathy (DN) in a rat model. Forty male Zucker diabetic fatty rats that spontaneously developed type 2 diabetes mellitus (DM) and 20 age-matched nondiabetic lean Zucker rats were included. Renal DKI scans and histological examinations were performed on the rats in batches at the end of the 4th, 8th, 12th, 16th, and 20th week after DM model was built. Based on renal histopathological appearance, included animals were divided into three groups: a nondiabetic control group, a DM group without DN, and an early DN group. Mean kurtosis (MK) and mean diffusivity (MD) values of renal cortex and medulla were analyzed statistically. MK values of renal cortex and medulla tended to increase from the control group to the early DN group, respectively, while MD values tended to decrease. The cutoff MD and MK values of renal cortex and medulla showed different values in discriminating early DN from controls. Among them, cutoff MK value of medulla of 0.62 was the best parameter (sensitivity, 93.9%; specificity, 96.4%; and area under the curve, 0.95). For discriminate early DN from DM without DN and DM without DN from controls, cutoff MK value of renal cortex or medulla achieved an area under the curve of 0.76–0.85. MR DKI may be valuable for the noninvasive detection of early DN, and MK value might serve as a more sensitive biomarker of early DN than MD value. • In this article, diffusion kurtosis imaging (DKI) was used to detect the changes in the kidneys due to early diabetic nephropathy (DN). • MR DKI may be valuable for the noninvasive detection of early DN. • The mean kurtosis values of renal cortex and medulla might serve as a more sensitive biomarker of early DN than the mean diffusivity values.

This Letter presents a compact microstrip diplexer. The high-frequency signal path is constructed by two electrically-coupling half-wavelength resonators, its external coupling adopts the tapped line structure. The low-frequency signal path is formed by two magnetically-coupling quarter-wavelength resonators, its external coupling is accomplished by microstrip coupling lines, which are formed from the tapped line structure and resonator of the high-frequency signal paths. The novel combination of the two signal path removes the need of T-junction in conventional diplexers. Meantime, the coupling strength of the two pass bands at the input port can be separately designed. A diplexer with Chebyshev frequency response at both signal paths with the central frequencies of 1.8/2.4 GHz is designed, fabricated and measured. The measured results give a good agreement with the simulated ones, which verifies the effectiveness of the diplexer.

To study conductor damage induced by different patterns of string pulley in process of tension stringing, damage experiment is performed on string pulleys with multi wheels and single wheel. Damages occurred on conductor by two different kinds of string pulleys are analyzed. Results show that there are no significant decrements in strength of conductor with trapezoidal conductor when it is passing through different patterns of string pulley. It indicates that damages on conductor with trapezoidal conductor caused by both types of string pulley are similar. It is also found that average strength of conductor with circular conductor decreases 1.60% and 2.99% when conductor is passing through string pulley with single wheel and multi wheels over twenty times. It is concluded that strength damage on conductor with circular conductor induced by multi wheels is a little larger than that by single wheel

Aim To determine whether diameters of the left gastric vein (LGV) and its originating vein are associated with endoscopic grades of esophageal varices. Methods Ninety-eight liver cirrhotic patients with hepatitis B undergoing magnetic resonance (MR) portography, and upper gastrointestinal endoscopy for grading esophageal varices were enrolled. Diameters of the LGV and its originating vein – the splenic vein (SV) or portal vein (PV) – were measured on MR imaging. Statistical analyses were performed to identify the association of the diameters with the endoscopic grades. Results Univariate analysis showed that the SV was predominantly the originating vein of the LGV, and diameters of the LGV and SV were associated with grades of esophageal varices. Diameters of the LGV (P = 0.023, odds ratio [OR] = 1.583) and SV (P = 0.012, OR = 2.126) were independent risk factors of presence of the varices. Cut-off LGV diameters of 5.1 mm, 5.9 mm, 6.6 mm, 7.1 mm, 7.8 mm and 5.8 mm; or cut-off SV diameters of 7.3 mm, 7.9 mm, 8.4 mm, 9.5 mm, 10.7 mm and 8.3 mm, could discriminate grades 0 from 1, 0 from 2, 0 from 3, 1 from 3, 2 from 3, and 0–1 from 2–3, respectively. Conclusion Diameters of the LGV and SV are associated with endoscopic grades of esophageal varices.

Conductor scheme is one of most key issues in the design of the transmission lines project, and it is significant for the construction cost and safe operation of transmission lines project. It can be aslo concluded from analysis on application of existing conductor that the appropriate decrease of number of bundle conductor and increase of the conductor cross-section will reduce lines loss, which has remarkable social-economic benefits. In this paper, the economic analysis of large cross-section conductor is conducted based on ±800kV DC Project. Some useful suggestions are given.

This chapter mainly introduces applications of stochastic differential game theory for Markov jump linear systems to finance and insurance. Firstly, a risk minimization problem is considered in a continuous-time Markovian regime switching financial model modulated by a continuous-time, finite-state, Markov chain.

Acute kidney injury (AKI) is a common complication of hospitalization that is characterized by a sudden loss of renal excretory function and associated with the subsequent development of chronic kidney disease, poor prognosis, and increased mortality. Although the pathophysiology of renal functional impairment in the setting of AKI remains poorly understood, previous studies have identified changes in renal hemodynamics, perfusion, and oxygenation as key factors in the development and progression of AKI. The early assessment of these changes remains a challenge. Many established approaches are not applicable to humans because of their invasiveness. Functional renal magnetic resonance (MR) imaging offers an alternative assessment tool that could be used to evaluate renal morphology and function noninvasively and simultaneously. Thus, the purpose of this review is to illustrate the principle, application, and role of the techniques of functional renal MR imaging, including blood oxygen level-dependent imaging, arterial spin labeling, and diffusion-weighted MR imaging, in the management of AKI. The use of gadolinium in MR imaging may exacerbate renal impairment and cause nephrogenic systemic fibrosis. Therefore, dynamic contrast-enhanced MR imaging will not be discussed in this paper.

The limiting width-thickness ratio of 2A12 angle Aluminum Alloy under axial compression is discussed using guide for design of transmission tower by American society of civil engineers, Chinese Technical regulation of design for tower and pole structure of overhead transmission line (DL/T5154-2002) and Chinese code for design of steel structures (GB50017-2003). The results show that the formula of Chinese code for design of steel structures about limiting width-thickness ratio is reasonable. And there is unreasonable in Chinese technical regulation of design for tower and pole structure of overhead transmission line and guide for design of transmission tower by American society of civil engineers about the formula of limiting width-thickness ratio. Some useful suggestions are given.

To investigate the appropriate inclined angles, spacing between caliper and square steel satisfying the requirement of caliper switching mechanism and the appropriate tooth parameters, the relation of inclined angles of caliper and meshing force is analyzed. And the hardness parameters of caliper and square steel are also analyzed. The appropriate tooth parameters are determined based on hardness parameters of caliper and square steel and tooth parameters of caliper.

Purpose: To study the risk grade of gastrointestinal stromal tumors (GISTs) with conventional MR imaging and diffusion-weighted imaging (DWI). Materials and Methods: The abdominal MR images with DWI of 23 patients with pathologically proven GISTs during January 2010 to May 2011 were retrospectively reviewed. The conventional MR imaging findings and apparent diffusion coefficient (ADC) values of the tumors related to the risk grade were analyzed. Results: In the 23 patients, there were 13 patients with high-risk, 5 with medium-risk, 5 with low-risk, and 0 with very low-risk GISTs. Most of the conventional MR findings of the tumors did not correlate with the risk grade. The only exception to this was the correlation between risk grade and the enhancement degree of the tumor after Gd-DTPA. The ADC values were, respectively, (1.04 ± 0.13) × 10−3 mm2·s−1, (1.59 ± 0.06) × 10−3 mm2·s−1 and (1.94 ± 0.08) × 10−3 mm2·s−1 (P < 0.05) in the high-, medium-, and low-risk grade groups. The ADC values of GISTs decreased with the increase of the risk grade of the tumors (r = −0.957; P < 0.05). Conclusion: DWI can be used to assess the risk grade of GISTs, but conventional MR imaging is of limited use. J. Magn. Reson. Imaging 2012; 36:1395–1401. © 2012 Wiley Periodicals, Inc.

A kind of multi-scaled texture feature based wavelet packet fusion approach be presented, which applies the principle of multi-channel filtering fusion to take wavelet fusion on the image with aplenty scaled texture feature and the multispectral image, meanwhile, for obtaining diversified scaled texture feature information and high resolution image, a regional characteristics based self-adapted wavelet packet fusion criteria be proposed. The experiment result and statistics analysis shows that the improved wavelet packet algorithm get the relatively improvement in the aspects of information amount and the clarity comparing with the traditional wavelet packet fusion.

According to the requirement of optical instrument illuminating system and performance characteristic of Ring-Shaped LED, a constant current circuit based on PT4115 chip is designed to drive Ring-Shaped LED. It is proved that not only the LED′s light intensity can be conditioned by PWM, but also its heat dissipation can be solved effectively. Moreover, compared with traditional halogen lamps, it has the advantage of the small volume and low-cost. Therefore, it can be widely applied to optical instrument illuminating system. This paper is applies innovative. Ring-Shaped LED of base on Amega 16 and PT4115 is applied for optical instrument illuminating system.

It is critical to understand the workload characteristics and resource usage patterns of available applications to guide the design and development of architecture of the future large scale servers. In this paper, we analyze the workload performance characteristics of the actual Bank Intermediary Business (BIB) characteristics with BIBmodel and BIBbench design work, and propose BIB performance workload and use case definitions. The analysis and comparisons of workload and use case illustrate that the workload performance characteristics of BIB is totally different with TPC benchmarks. With the development of economy and technology, the requirements for BIB servers are important in modeling, benchmarks developing and workload performance characteristics studying are increased nowadays.

Based on the segmental joint tests, it was found that the practical range of joint flexural rigidity was in range of 8500-29000kN•m/rad. A simplified method for determining the stiffness reduction factor of tunnel lining() was proposed using results from the segmental joint tests in which some parameters were obtained by calibration against a 3D Numerical analysis. The influence of joint flexural rigidity, soil resistance coefficient, thickness of tunnel lining and tunnel calculation radius on the stiffness reduction factor of tunnel lining was examined. The stiffness reduction factor can be simply expressed as a function of joint flexural rigidity ratio, soil resistance coefficient, thickness of tunnel lining and tunnel calculation radius for the typical tunnel lining.

Energy consumption is the core issue in wireless sensor networks (WSN). To generate a node energy model that can accurately reveal the energy consumption of sensor nodes is an extremely important part of protocol development, system design and performance evaluation in WSNs. In this paper, by studying component energy consumption in different node states and within state transitions, the authors present the energy models of the node core components, including processors, RF modules and sensors. Furthermore, this paper reveals the energy correlations between node components, and then establishes the node energy model based on the event-trigger mechanism. Finally, the authors simulate the energy models of node components and then evaluate the energy consumption of network protocols based on this node energy model. The proposed model can be used to analyze the WSNs energy consumption, to evaluate communication protocols, to deploy nodes and then to construct WSN applications.

In wireless sensor networks, the node faults often occurred in scenes because of severe disturbance, harsh environment and inherent weakness of the networks. In this paper, a fault tolerance directed diffusion protocol, termed fault-tolerant algorithm with recoverable nodes (FTA-RN), is proposed to extend the lifetime of the wireless sensor network based on recoverable host nodes, in which a heartbeat detection algorithm is applied to detect node failure. In FTA-RN, each recoverable intermediate node has a redundant node for fault tolerant function to increase the rate of successful data reception. The nodes are designed based on a kind of recoverable model to prevent the disadvantage of nodes instantaneous fault. Moreover, the energy of host nodes can be used efficiently in recovering model. The simulation result shows that more messages can be received on the sink node using FTA-RN compared with the traditional DD protocol in tolerable amount of delay time and energy consumption, and the lifeti...

Slot bottom size has directly effect on conductor abrasion,Chinese Technical Regulation of design for Stringing blocks of overhead transmission lines (DL/T371-2010) clearly states that slot bottom size should be no less than 20 times of the size of conductor to be extended. In this paper, based on effect of slot bottom size on conductor abrasion,the size of slot bottom of stringing pulley is analyzed. Some useful suggestions are given.

The new device of hydraulic pushing device achieves enclasping of clamping device and steel rail locking effect by the wedge clamping on the both side of the steel rail, so as to provide thrust and pulling force action point for the cylinder of hydraulic equipment. Compare with other devices, the new type of device has more advantages like : simple structure, reliable clamp, easy erection and high efficiency. To further optimize the mechanical clamping device, the pressure and the friction coefficient of the wedge. the shell and the rail were analyzed emphatically. Combining experimental data and the reasonable angle of wedge and optimizing design direction was applied.

To determine associations of patterns of portosystemic collaterals and diameters of portal venous system in cirrhotic patients with hepatitis B on magnetic resonance (MR) imaging with Child-Pugh classification.Eighty-eight consecutive patients with cirrhosis resulting from chronic hepatitis B graded by Child-Pugh classifications were recruited and undergone MR portography. Patterns of the collaterals (presented as no collateral, isolated esophageal varices, and esophageal varices combined with other shunts), and diameters of portal venous system including portal vein (PV), left portal vein (LPV), right portal vein (RPV), splenic vein (SV) and superior mesenteric vein (SMV) were assessed statistically to determine associations of patterns of collaterals and diameters of the portal veins with Child-Pugh classification.From no collateral, to isolated esophageal varices, and to the varices combined with other shunts, the Child-Pugh classifications tended to increase (r=0.516, P0.001). Diameters of PV, LPV, RPV, SV and SMV tended to increase from Child-Pugh A to B but decrease from B to C. Differences in diameter of LPV and SV were significant between Child-Pugh A-B and C (all P0.05) while no differences in diameters of other portal veins were found (all P0.05). For discriminating Child-Pugh A-B from C, either a cut-off LPV diameter of 8.98mm or SV diameter of 9.10mm achieved a sensitivity of 67%-70%, specificity of 51%-53%.Patterns of portosystemic collaterals and diameters of LPV and SV tend to be associated with Child-Pugh classifications of cirrhosis.

OBJECTIVE: The aim of this study was to determine whether and how the diameter of the vein that gives rise to the inflowing vein of the esophageal and gastric fundic varices secondary to posthepatitic cirrhosis, as measured with multidetector-row computed tomography, could predict the varices and their patterns. METHODS: A total of 106 patients with posthepatitic cirrhosis underwent multidetector-row computed tomography. Patients with and without esophageal and gastric fundic varices were enrolled in Group 1 and Group 2, respectively. Group 1 was composed of Subgroup A, consisting of patients with varices, and Subgroup B consisted of patients with varices in combination with portal vein-inferior vena cava shunts. The diameters of the originating veins of veins entering the varices were reviewed and statistically analyzed. RESULTS: The originating veins were the portal vein in 8% (6/75) of patients, the splenic vein in 65.3% (49/75) of patients, and both the portal and splenic veins in 26.7% (20/75) of patients. The splenic vein diameter in Group 1 was larger than that in Group 2, whereas no differences in portal vein diameters were found between groups. In Group 1, the splenic vein diameter in Subgroup A was larger than that in Subgroup B. A cut-off splenic vein diameter of 8.5 mm achieved a sensitivity of 83.3% and specificity of 58.1% for predicting the varices. For discrimination of the varices in combination with and without portal vein-inferior vena cava shunts, a cut-off diameter of 9.5 mm achieved a sensitivity of 66.7% and specificity of 60.0%. CONCLUSION: The diameter of the splenic vein can be used to predict esophageal and gastric fundic varices and their patterns.

Heart diseases are the serious health threats to human beings. Traditional cardiac monitoring systems are unsatisfactory to prevent the sudden death events caused by heart diseases. A pervasive cardiac monitoring system is thus developed, which can provide a real-time continuous cardiac care and arrhythmias detection service for any person at any time in any place. This paper gives a detailed description about the architecture and operation fashion of this system. This system has been tested on more than 30 patients in a hospital and more than 10 sportsmen in a training field, and also compared with the HP telemetry system. Concerning the clinical off-line arrhythmia detection, this system has similar results with the HP telemetry, but concerning the outdoor on-line ambulatory arrhythmia detection, this system has better performance results. The evaluation results prove that this system meets the requirements of real-time cardiac monitoring and diagnosing applications.

At present, the OSs (Operating system) employed for WSN (wireless sensor networks) are either satisfied with only one or two application classes or unsuitable for strict-constrained resources. In view of a variety of WSN applications, there is a need of developing a self-adaptable and self-configurable embedded real-time operating system (RTOS). This paper presents a resource-aware and low-power RTOS termed LIMOS. This kernel adopts a component-based three-level system architecture: action (system operation), thread (component) and event (container). In accordance, a predictable and deterministic two-level scheduling mechanism is proposed: 'non pre-emption priority based' high level scheduling for events and 'preemptive priority-based' low level scheduling for threads. Employing the concepts of LINDA language, LIMOS provides a simplified tuple space and a light IN/OUT system primitive-pair to achieve system communication and synchronization. LIMOS is capable of self-adapting to run on two operation modes: event-driven and multi-threading, with respect to the application diversity. The performance evaluation and comparison shows LIMOS has tiny resource consumption and is fit for the real-time applications. Currently LIMOS has been ported on several hardware platforms for different WSN applications.

Importance A randomized clinical trial is needed to evaluate what is the best photodynamic therapy (PDT) protocol to use for acute central serous chorioretinopathy. Objective To compare the efficacy and safety of a 50% dose of verteporfin (a method of PDT) with the efficacy and safety of a 30% dose for acute central serous chorioretinopathy. Design, Setting, and Participants A multicenter, noninferiority, double-masked, randomized, controlled, clinical trial in which 131 patients (131 eyes) with acute central serous chorioretinopathy for less than 6 months were recruited with a follow-up of 12 months from university-based ophthalmology practices. Interventions Patients were randomly assigned to either a 50% dose of verteporfin (the 50%-dose PDT group) or a 30% dose (the 30%-dose PDT group). Main Outcomes and Measures The 2 primary outcome measures were the proportion of eyes with complete absorption of subretinal fluid and the proportion of eyes with complete disappearance of fluorescein leakage at 6 and 12 months. The secondary outcome measures included the subretinal fluid recurrent rate, the fluorescein leakage recurrent rate at 12 months, the mean best-corrected visual acuity, the retinal thickness of the foveal center, and the maximum retinal thickness at each scheduled visit. Results The noninferiority of the 30%-dose PDT compared with the 50%-dose PDT for the primary outcomes was not demonstrated. The optical coherence tomography–based improvement rate in the 30%-dose PDT group was less than that in the 50%-dose PDT group both at 6 months (73.8% vs 92.9%; α = 0.0125, P = .006) and at 12 months (75.4% vs 94.6%; α = 0.0125, P = .004). The fluorescein angiography–based improvement rate in the 30%-dose PDT group was less than that in the 50%-dose PDT group both at 6 months (68.9% vs 91.1%; α = 0.0125, P = .003) and at 12 months (68.9% vs 92.9%; α = 0.0125, P = .001). The subretinal fluid recurrence rate in the 30%-dose PDT group was greater than that in the 50%-dose PDT group (24.0% vs 5.7% at 12 months; P = .010, determined by use of the log-rank test). The fluorescein leakage recurrent rate in the 30%-dose PDT group was significantly higher than that in the 50%-dose PDT group (16.7% vs 3.8% at 12 months; P = .03, determined by use of the log-rank test). No ocular adverse event was encountered in the study. Conclusions and Relevance A 50% dose of verteporfin may be more effective at resolving subretinal fluid and fluorescein leakage, and with better visual outcomes, than a 30% dose for acute central serous chorioretinopathy. Trial Registration clinicaltrials.gov Identifier:NCT01574430