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The characteristics of patients with colorectal cancer who have benign mesenteric lymph node enlargement are not well documented.The aim of this study is to assess the clinical and prognostic significance of benign mesenteric lymph node enlargement in patients with colorectal cancer.This is a prospective cohort study.This study was conducted at multitertiary institutions.We included 601 patients with stage 0, I, and II colorectal cancer in Tianjin, Shandong, and Zhejiang from January 2010 to April 2014. Patients underwent curative surgery and were separated into 2 groups by the presence of benign mesenteric lymph node enlargement: the enlargement group (n = 275) and the control group (n = 326).Univariate log rank and multivariate Cox regression analyses were constructed to identify risk factors for recurrence and mortality.The risk of recurrence in the enlargement group after curative resection was significantly lower than in the control group, with the 1-, 3-, and 5-year disease-free survival rates being 97.1%, 91.6%, and 86.9% in the enlargement group and 95.7%, 86.2%, and 78.2% in the control group (p = 0.004). The postoperative 1-, 3-, and 5-year overall survival rates were 99.6%, 94.9%, and 90.5% in the enlargement group and 99.4%, 91.4%, and 82.1% in the control group (p = 0.001). Patients in the enlargement group had a higher percentage of patients at a younger age, family tumor history, right-sided tumors, and larger tumor size compared with the control group. For patients in the enlargement group, no significant correlation was observed between the number of enlarged lymph nodes and disease-free survival or overall survival (p = 0.113 and 0.386). Adjusted Cox regression model showed that benign mesenteric lymph node enlargement was an independent prognostic risk factor for both disease-free survival (HR, 0.587; 95% CI, 0.399-0.861; p = 0.007) and overall survival (HR, 0.506; 95% CI, 0.328-0.779; p = 0.002).No immunological results could be compared with clinicopathological findings.The study indicates that benign mesenteric lymph node enlargement can be a useful positive factor in predicting recurrence and long-term survival concerning patients with colorectal cancer. See Video Abstract at http://links.lww.com/DCR/B785.ANTECEDENTES:Las características de los pacientes portadores de cáncer colorrectal con agrandamiento benigno de los ganglios linfáticos mesentéricos no se encuentran bien documentados.OBJETIVO:El objetivo de este estudio es evaluar la importancia clínica y pronóstica del agrandamiento benigno de los ganglios linfáticos mesentéricos en pacientes con cáncer colorrectal.DISEÑO:Este es un estudio de cohorte de tipo prospectivo.AJUSTE:Este estudio se llevó a cabo en instituciones de educación superior.PACIENTES:Incluimos a 601 pacientes con cáncer colorrectal en estadio 0, I, II en Tianjin, Shandong y Zhejiang desde enero de 2010 hasta abril de 2014. Los pacientes fueron sometidos a cirugía curativa y fueron separaron en dos grupos tomando en cuenta la presencia del agrandamiento benigno de los ganglios linfáticos mesentéricos: grupo con agrandamiento (n = 275) y grupo control (n = 326).PRINCIPALES MEDIDAS DE RESULTADO:Se construyeron análisis de rango logarítmico de una variante y de regresión de Cox con variante múltiple para identificar los factores de riesgo de recurrencia y mortalidad.RESULTADOS:El riesgo de recurrencia en el grupo con agrandamiento tras la resección curativa fue significativamente menor que en el grupo de control, con tasas de periodo libre de enfermedad a los 1, 3 y 5 años de 97,1, 91,6, y 86,9% en el grupo de agrandamiento y con tasas de 95,7, 86,2, y 78,2% en el grupo control respectivamente (p = 0,004). Las tasas postoperatorias de supervivencia general a los 1, 3 y 5 años fueron 99,6, 94,9, y 90,5% en el grupo de agrandamiento y de 99,4, 91,4, y 82,1% en el grupo de control, respectivamente (p = 0,001). Los pacientes del grupo con agrandamiento tenían un porcentaje más elevado de menor edad, antecedente familiar tumoral, tumores del lado derecho y de mayor tamaño tumoral con respecto al grupo de control. Para los pacientes con agrandamiento, no se observó una correlación significativa entre el número de ganglios linfáticos agrandados y el periodo libre de enfermedad o la supervivencia general (p = 0,113 y 0,386). El modelo de regresión de Cox ajustado mostró que el agrandamiento benigno de los ganglios linfáticos mesentéricos era un factor de riesgo pronóstico independiente tanto para la supervivencia libre de enfermedad (cociente de riesgo 0,587; IC del 95%: 0,399-0,861; p = 0,007) como para la supervivencia global (cociente de riesgo 0,506; IC del 95%: 0,328- 0,779; p = 0,002).LIMITACIONES:No fue posible comparar los resultados inmunológicos con los hallazgos clínico-patológicos.CONCLUSIONES:El estudio indica que el agrandamiento benigno de los ganglios linfáticos mesentéricos puede ser un factor positivo útil para predecir la recurrencia y la supervivencia a largo plazo en pacientes con cáncer colorrectal. Consulte Video Resumen en http://links.lww.com/DCR/B785. (Traducción-Dr. Osvaldo Gauto).

Cutting performance and tool wear of two ceramic tools, SiAlON and TiC-whisker-reinforced Si3N4, in the side milling processes of Inconel 718 are evaluated in comparison, including cutting force, temperature, surface morphology, tool wear and corresponding mechanism. Results show that these two ceramic tools has advantages and disadvantages respectively, due to the properties of ceramic matrixes and the evolutions of build-up edges. SiAlON ceramic tool has better resistance to wear, but causes poor surface quality. TiC-whisker-reinforced Si3N4 ceramic tool generates better surface quality, but bears severe wear. Brittle damage, as the main mode of wear, occurs to both ceramic tools in different formations. SiAlON ceramic tool is featured by crater-like damage on blades while TiC-whisker-reinforced Si3N4 ceramic tool is featured by whole-layer damage on flank faces.

To further improve the dynamic and anti-interference performance of permanent magnet synchronous motor (PMSM) control system, a dual closed loop model predictive control (MPC) strategy combining with grey prediction and reduced-order Luenberger observer is proposed in this paper for speed and current control. To be specific, firstly, the dual closed loop MPC strategy is introduced based on the mathematical model of PMSM, that is, the model predictive controller is used for the outer loop of speed, and the deadbeat predictive controller for the inner loop of current. Secondly, considering the grey prediction method can establish grey model and whiten the system grey quantity to some extent, it is used in the PMSM control system to improve the dynamic performance. Finally, to solve the problem that the motor is easy to be affected by disturbances, a reduced-order Luenberger observer is designed to combine with the model predictive controller to improve the system anti-interference performance. The simulation results show that the dual MPC strategy based on grey prediction makes the system more stable and dynamic response faster, while the dual MPC strategy combining with the grey prediction and the reduced-order Luenberger observer makes the system more resistant to load disturbance.

Powder metallurgy superalloy FGH96 is being extensively used to fabricate the hot section of the aeronautic and astronautic turbine engines owing to its superior mechanical properties maintained at high-temperature environments. However, machining such a difficult-to-cut material entails high cutting forces, excessive cutting temperatures and serious tool wear. Although Sialon ceramic tools have been successfully employed in the turning and milling processes for the Inconel 718, their application for the machining of powder metallurgy superalloys is very limited. In the current work, a series of high-speed milling trials were conducted to examine the influences of the milling parameters on the cutting response and tool wear mechanisms during the milling of FGH96 with Sialon ceramic mills under dry conditions. The milling forces and machining temperatures were studied with respect to the used process parameters. The quality of cut surfaces and wear signatures of ceramic tools were also discussed. Results indicate that the resultant cutting forces only decrease until the cutting speed exceeds 315 m/min. Furthermore, the Sialon tools seem more suitable for the rough machining of FGH96 considering the surface finish and large residual tensile stress existing on the milled surface. Finally, the adhesion wear is the primary wear mode occurring at the flank surface, while the edge chipping and flaking dominate the failure of the tool rake surface.

FGH96 is one kind of nickel-based superalloy, being widely used in aero engine hot end components due to its superior mechanical properties, while its machinability has been a challenge because of rapid tool wear and low machining efficiency. Recently, ceramic tools have gained widespread attention for their superior performance maintained at high temperatures. This work aims to study the wear mechanisms and the wear effects of monolithic Sialon ceramic tool in the side milling of superalloy FGH96. The specific influences of average flank wear on the side milling forces, machining temperatures, surface quality and micro-hardness of subsurface and the wear modes in the early and serious stage are analyzed. The results indicate that the milling temperatures, machined surface roughness and the depth of hardening layer will increase as the wear increases. While parallel to the cutting direction, the machined surface roughness is about 1.8 μm without significant changes until entering the serious wear stage. The milling force tends to undergo a decrease when the VB is about 0.22 mm, since the temperature is close to the solute temperature of γ’ phase in this stage. The main wear modes of monolithic ceramic tools are adhesive wear and flanking in the flank surface.

Carbon/epoxy and carbon/polyimide composites are, respectively, high-performance thermoset and thermoplastic polymer matrix composites being widely utilized in the modern industrial fields due to t...

In this paper, high-speed milling aluminum alloy 7050-T7451 was studied using finite element simulation. First, based on two-dimensional orthogonal cutting model, the influence of the cutting speed on the cutting force was studied in the process of machining. The results shown that with the increase of cutting speed, the cutting force originally increased and then decreased. When the feed per tooth increased, the inflection point of cutting speed would increase. Besides, when the cutting speed was larger than 4000m/min, the cutting temperature decreased. By three-factor and three-level simulation schemes, the influence of tool rake angle, relief angle and feed per tooth on cutting force were analyzed. According to three-dimensional cutting model, the effect of cutting edge inclination angle on cutting force was researched. Last, the cutting forces of simulation were compared against the experimental results. The maximum cutting force error was 10.4%. According to the law of simulation, the number of experiments is reduced in the process of optimizing the cutting parameters.

Diallyl trisulfide (DATS) is a bioactive compound in garlic. The anti-obesity effect of garlic oil has been reported, but the role and mechanism of DATS in preventing obesity remain to be explored.Studies with high-fat-diet-induced obese mice and 3T3-L1 adipocytes are performed. The results show that DATS significantly reduces lipid accumulation and repairs disordered metabolism in vivo by restraining adipogenesis and lipogenesis, and promoting lipolysis and fatty acid oxidation in white adipose tissue. In cells, DATS plays different roles at different stages of adipocyte differentiation. Notably, DATS reduces lipid accumulation mainly by inhibiting adipogenesis and lipogenesis at the late stage. KLF15 is knocked down in 3T3-L1 cells, which eliminate the inhibitory effect of DATS on adipogenesis and lipogenesis. The dual-luciferase reporter and ChIP assays indicate that DATS can inhibit the transcriptional activation function of KLF15 on PPARγ by inhibiting the binding of KLF15 to PPARγ promoter. The function comparison of structural analogs and the intervention of dithiothreitol show that disulfide bond is crucial for DATS to work.DATS prevents obesity by regulating the transcriptional activation function of KLF15 on PPARγ.

Colonoscopy is commonly used to screen for colorectal cancer (CRC). We develop a deep learning model called CRCNet for optical diagnosis of CRC by training on 464,105 images from 12,179 patients and test its performance on 2263 patients from three independent datasets. At the patient-level, CRCNet achieves an area under the precision-recall curve (AUPRC) of 0.882 (95% CI: 0.828–0.931), 0.874 (0.820–0.926) and 0.867 (0.795–0.923). CRCNet exceeds average endoscopists performance on recall rate across two test sets (91.3% versus 83.8%; two-sided t-test, p, Colonoscopy is the most commonly used tool to screen for colorectal cancer (CRC). Here, the authors develop a deep learning model to perform optical diagnosis of CRC by training on a large data set of white-light colonoscopy images and achieve endoscopist-level performance on three independent datasets.

This study was conducted to investigate the particulate passage rate, nutrient characteristics and fermentation parameters across the gastrointestinal tract (GIT) in lactating dairy cows fed cereal straws in comparison with alfalfa hay. Eighteen multiparous Holstein cows were randomly assigned to one of three experimental diets consisting of 55% concentrate, 15% corn silage and 30% different forage sources as follows (% of dry matter [DM]): (i) 23% alfalfa hay and 7% Chinese wild rye hay (AH); (ii) 30% corn stover (CS); and (iii) 30% rice straw (RS). The Cr-mordanted corn silage-neutral detergent fibre was used to estimate the passage flow at week 14. After 14-week feeding, the animals were slaughtered to collect the gastrointestinal digesta. Dietary forage sources had little effect on the fractional passage rates in the rumen (range from 5.05 to 6.25%/hr) or hindgut (range from 4.49 to 5.24%/hr). Total volatile fatty acid (VFA) concentration in the caecum was highest, followed by the rumen, colon and rectum, and the lowest in the abomasum and duodenum, indicating that the large intestines, especially caecum, are the important positions for carbohydrate degradation. Greater proportion of propionate and butyrate and lower acetate were found in the AH compared to CS or RS in colon, but higher acetate in abomasum was found in the cows fed CS or RS compared to AH. In conclusion, cereal straw diets did not change the particulate passage rate in the rumen and hindgut which might be mainly due to the similar DM intake among these three diets. Different forage source diets significantly changed VFA proportion in the abomasum and colon, indicating the existence of different digestion or absorption rates in these tracts among the experimental diets.

A fractured catheter in the posterior auricular vein is exceedingly rare. Imaging revealed that it was migrating freely and currently overlapped the temporal bone. With multidisciplinary cooperation, general anesthesia, and three-dimensional computed tomography (3D-CT) for guidance, the catheter was removed uneventfully.

Aim. To evaluate the clinical risk factors influencing overall survival of patients with duodenal adenocarcinoma after potentially curative resection. Methods. A series of 201 patients with primary duodenal adenocarcinoma who underwent surgery from 1999 to 2014 at Chinese Medical Academic Cancer Hospital were studied by retrospective chart review and subsequent telephone follow-up. Results. Resectional surgery was performed in 138 of the 201 patients to attempt curative treatment, while 63 patients were treated with palliative surgery. Median survival of patients who underwent resectional operation was 57 months, whereas that of patients who had palliative surgery was shorter, 7 months (p<0.001). For patients who underwent radical resection, the overall 1-, 3-, and 5-year survival rates were 87.3, 59.1, and 44.1%, respectively. Multivariate Cox regression analysis revealed that lymph node metastasis (HR 31.76, 2.14 to 470.8; p=0.012) and vascular invasion (HR 3.75, 1.24 to 11.38; p=0.020) were independent prognostic factors negatively associated with survival in patients undergoing curative resection. There was no survival difference between the groups treated by the pancreaticoduodenectomy (n=20) and limited resection (n=10) for early-stage duodenal adenocarcinoma (p=0.704). Conclusions. Duodenal adenocarcinoma is a rare disease. Curative resection is the best treatment for appropriate patients. Lymph node metastases and vascular invasion are negative prognostic factors.

Since the sliding mode control (SMC) of the sliding mode can be designed, and is independent of parameter variations and disturbances outside of the control target, the sliding mode control has the advantages of fast response, insensitive to the parameter change and external disturbance, and is easy to realize other control systems. It is an effective way to solve nonlinear problems. Characteristics inherent nonlinearity and strong coupling of the switched reluctance motor (SRM) itself, based on the traditional text directly on the instantaneous torque control, the torque distribution function provides a real-time compensation scheme. In Matlab/Simulink environment, the simulation results show that the improved control strategies can reduce torque ripple of SRM, increase the robustness of the system.

The tropical cyanobacterium Cylindrospermopsis raciborskii is of particular concern for its invasive characteristics and production of the toxin cylindrospermopsin (CYN). The present study represents the first attempt to determine the distribution of C. raciborskii and CYN in tropical China. The presence of C. raciborskii and CYN, as well as the composition of phytoplankton, was determined from a total of 86 samples from 25 urban reservoirs for drinking water supply in Dongguan City of South China. The presence of C. raciborskii was observed in 21 of the 25 reservoirs and confirmed that this species has been widely distributed in the investigated reservoirs. C. raciborskii accounted for between 0.1 and 90.3 % of the total phytoplankton biomass and contributed to the majority of the phytoplankton in some reservoirs such as Tangkengbian and Xiagongyan. Its biomass was negatively correlated with NO3 −-N concentration and Secchi depth. Dissolved CYN was detected in more than one-half of the reservoirs with concentrations up to 8.25 μg L−1, and it positively correlated with C. raciborskii biomass. Dissolved microcystins (MCs) were detected in 12 of the 25 reservoirs with a maximum concentration 1.99 μg L−1. Our data strongly suggest that C. raciborskii and CYN could be important health hazards in urban reservoirs of South China and that more data are needed for further assessment.

A 1.2 V, 10 b, 40 MS/s pipelined ADC fabricated in 0.13µm one-poly eight-metal (1P8M) standard CMOS process with MIM capacitors is presented. This ADC used a novel low-variation on-resistance CMOS sampling switch to improve the nonlinear effect and a two-stage recycling folded-cascode (RFC) amplifier with hybrid frequency compensation for power saving and low voltage supply requirements. By implementing with 2.5-bit/stage and an improved amplifier sharing scheme, very competitive power consumption and small die area can be achieved. A test chip was fabricated for confirmation, a peak signal-to-noise-plus-distortion ratio (SNDR) of 56.76 dB with 40MS/s at 19.3 MHz input signal and a power dissipation of 23.2 mW was achieved.

The loss of Switched Reluctance Motor (SRM) may cause the motor overheat. In many fields, the application of SRM needs a deeply research and analysis on heat radiating problem. To optimize SRM losses, a 2D transient model of three-phase 12/8 SRM is established with the finite element method following current chopping control principle. Through the Ansoft software analysis, the motor core flux density waveforms are obtained. The hysteresis losses and eddy-current losses in different parts of the motor are calculated using the ellipse method. Changing the structural parameters of the motor to modify gap length, the new motor model is established to optimize motor losses. After the simulation analysis, the comparison of efficiency and losses for motor model with different parameters can help us get the optimal motor model. The result shows that through the optimization, the total loss of the SRM is reduced by 23%. The research in this paper provides the theoretical basis to further optimization and the study on the performance of the SRM.

Objective To construct recombinant adeno-associated virus co-expressing human vascular epithelial growth factor 165(hVEGF165) and bone morphogenetic protein 7(hBMP7), measure the virus titer and verify the recombination. Methods The AAV helper-free system was used as basis to generate recombinant AAV. The IRES sequence of plasmid pIRES was cut down and subcloned into ITR/ MCS containing vector pAAV-MCS to construct recombinant plasmid pAAV-MCSa-IRES-MCSb. The hVEGF165 and hBMP7 gene was amplified by PCR and inserted into upstream MCSa and downstream MCSb respectively. Then, recombinant plasmid pAAV-hVEGF165-IRES-hBMP7, pAAV-RC and pHelper were co-transfected into AAV-293 cells to complete rAAV-hVEGF165-IRES-hBMP7 packaging. The GFP labeled rAAV-IRES-GFP was simultaneously packaged by using the parallel plasmid pAAV-IRES-hrGFP. The efficiency of AAV packaging was monitored under fluorescent microscope and recombinant viral particles were harvested from infected AAV-293 cells. The virus titer was measured by infecting AAV-HT1080 cells, and the recombinant AAV-hVEGF165-IRES-hBMP7 was verified by PCR of the exogenous interest genes. Results Recombinant pAAV-hVEGF165-IRES-hBMP7 was verified by double digestion. GFP expression in AAV-293 could be observed under fluorescent microscope 72 h after transfection and the system provided a high packing ratio of 95%. The recombinant adeno-associated virus has a high titer of 5.5 × 1011 vp/ml, and AAV-HT 1080 was infected at a ratio of 90%. The recombinant virus was confirmed by PCR of exogenous hBMP7 and hVEGF165 gene. Conclusion Recombinant rAAV-hVEGF165-IRES-hBMP7 was successfully constructed with a high virus titer, which may offer foundation for in vitro and in vivo experiments of hVEGF165 and hBMP7 co-expression and provide a new method for gene therapy of bone regeneration.

Closed-loop control of an integrated dual-inverter to drive two permanent magnet motors independently is presented and evaluated experimentally. By utilizing the neutral point of the three-phase main motor, only two inverter legs are needed for the two-phase auxiliary motor. A modified field oriented control scheme for this integrated inverter was introduced and employed in real-time control. Experimental results show that the inverter is able to control two drives independently. An integrated, component-count-reduced drive is achieved.

Effectively detecting rotor eccentricity faults in the presence of a load torque oscillation is an important concern for some types of industrial loads such as reciprocating compressors. In a closed-loop induction motor drive, eccentricity related fault characteristic harmonics are introduced into both stator current and voltage spectra due to the low-pass filtering property in PI controllers. Therefore, both stator current and voltage harmonics need to be monitored simultaneously. However, a rotor position dependent load torque oscillation has exactly the same effect as a rotor eccentricity fault on the spectrum. Harmonics in stator current and voltage spectra resulting from a load oscillation usually have larger magnitudes, which leads to an ambiguity in the detection of rotor eccentricities. This paper develops an effective method to eliminate load oscillation effects for rotor eccentricity detection in a closed-loop vector-controlled induction motor by monitoring eccentricity induced negative sequence information in both stator currents and voltages. A significant advantage of this scheme is its independence on motor parameters. Experimental results validate the efficacy of using the negative sequence indicator. The practical issues involved in separating the eccentricity related negative sequence information from those resulting from a stator inter-turn fault are also addressed.

A new method for the detection of rotor eccentricity faults in a closed-loop drive-connected induction motor is reported in this paper. Unlike a line-fed electric motor, the eccentricity-related fault signals exist in the current as well as the voltage of a drive-connected motor. Meanwhile, since the speed and therefore the mechanical load can change widely in variable speed applications, the amplitudes of the fault signals will vary accordingly. An artificial neural network is used in the detection to learn the complex relationship between the eccentricity-related harmonic amplitudes and the operating conditions. The neural network can estimate a threshold corresponding to an operating condition, which can then be used to predict the motor condition. The neural network is trained and tested with data collected on drive-connected 4-pole, 7.5 Hp, three-phase induction motors. The experimental results validate that the detection method is feasible over the whole range of operating conditions of the experimental motors.

This paper discusses a new method to detect rotor eccentricity faults in induction motors using a so-called surge test that is applied to the stator windings. Rotor eccentricity faults cause an asymmetrical air gap in induction motors, which makes the surge waveform shape depend on rotor position. The change of surge waveform per revolution can be used to indicate any abnormal air gap problem clearly. The feasibility of this detection scheme is verified by experiments. The surge test is a nonintrusive, cost-efficient, and reliable offline method that is particularly useful for routine and predictive maintenance.

CoFe2O4/SiO2 nanocomposites have been prepared by a sol-gel procedure, starting from tetraethylorthosilicate and metallic nitrates. The formation mechanism of the composites was characterized by differential scanning calorimetry, infrared spectroscopy, transmission electron microscopy, X-ray diffraction and Raman spectroscopy. The magnetic properties were measured using a vibrating sample magnetometer. It was found that xerogel obtained at low temperatures was amorphous. Heat treatment at 400°C resulted in the partial formation of CoFe2O4 clusters. On further increasing the annealing temperature to 800°C, CoFe2O4 nanocrystals with diameters of ∼17 nm could be dispersed in the silica matrix. The formation of CoFe2O4 clusters was accompanied with the rearrangement of silica network, and the enhancement of the interaction between the metal ions and the surrounding silica network. The interaction between the particles and the matrix would be weakened or even disappear when annealing temperature was raised to as high as 800°C. Both the coercive field and the density of magnetization of composites would increase with an increase in the annealing temperature.

Nanocomposites with cobalt ferrite nanoparticles uniformly dispersed in silica have been successfully synthesized. The effects of the thermal treatment temperature and the initial drying temperature on the structural and magnetic properties of the nanocomposites were examined. The crystalline phase, the particle size, and the homogeneity of the resulting nanocomposites were studied by X-ray diffraction, IR spectroscopy, differential scanning calorimetry, transmission electron spectroscopy and vibrating sample magnetometer. The xerogels were amorphous. Heat treatment at 400 °C resulted in CoFe 2 O 4 clusters being partially formed and when the heat treatment temperature was increased to 600 °C, CoFe 2 O 4 clusters were formed in large quantities. The formation reaction of CoFe 2 O 4 clusters was accompanied by a rearrangement of the silica matrix network. On further increasing the heat treatment temperature to 800 °C, materials with CoFe 2 O 4 nanocrystals, well crystalline dispersed in the silica matrix, could be obtained. By increasing the annealing temperature, composites with a progressive increase of the coercivity and of the remanent magnetization were produced. The remarkable effect of initial drying temperature on the particle size of cobalt ferrite suggested that a well-established silica network provided an effective confinement to the coarsening and aggregation of CoFe 2 O 4 nanoparticles.

To assess prognostic benefits of intraoperative electron beam radiation therapy (IOERT) in patients with nonmetastatic locally advanced pancreatic cancer (LAPC) and evaluate optimal adjuvant treatment after IOERT. A retrospective cohort study using prospectively collected data was conducted at the Cancer Hospital of the Chinese Academy of Medical Sciences, China National Cancer Center. Two hundred forty-seven consecutive patients with nonmetastatic LAPC who underwent IOERT between January 2008 and May 2015 were identified and included in the study. Overall survival (OS) was calculated from the day of IOERT. Prognostic factors were examined using Cox proportional hazards models. The 1-, 2-, and 3-year actuarial survival rates were 40%, 14%, and 7.2%, respectively, with a median OS of 9.0 months. On multivariate analysis, an IOERT applicator diameter

Subsea power transmission and distribution is an emerging technology that may enable the oil and gas industry to produce hydrocarbon reserves in deeper and more remote offshore waters. The longer tieback subsea operations will likely require pumps and compressors driven by electric motors to be located on the sea floor to pressure boost the oil and gas to surface and/or onshore platforms. Existing HVAC and HVDC technologies are efficient means for subsea power transmission and distribution. However, they are subject to a variety of limitations, for instance, the single-point failures that would impact production uptime. Furthermore, it is challenging to implement subsea bulk power transmission and distribution by using existing architectures due to the footprint, weight and electrical insulation requirements. This paper describes a subsea power distribution architecture — AC ring. It can be used to interface a high-voltage bulk power transmission network, either AC or DC, to a subsea multi-load AC system. The new topology uses series-connected, by-passable, open-winding transformers to provide better modular design flexibility. The system is expected to be more reliable than conventional “hub and spoke” architectures and more technically feasible regarding practical subsea equipment designs.Copyright © 2010 by ASME

Simulation and modeling provide a fast and cost-efficient way for sophisticated analysis and design of power converters. This paper presents various approaches of dynamic modeling of power electronic systems. It discusses practical technical issues in simulation and system modeling. Two demonstrative examples, the power converters in healthcare and energy systems, by using different simulation package and platforms are provided.

High-speed electrical machines at multi-MW power level are being designed to drive high-speed compressor trains in oil and gas industry applications and for directly driving generators with gas turbines for shipboard and mobile power generation applications. The paper describes a converter topology to address such high power high frequency drive requirements. The proposed topology uses a three-phase bridge with series-connected single-phase bridges in each phase to obtain a four-level configuration. Optimized low pulse-count synchronous switching is used to limit the switching frequency of the individual devices; yet obtain the required power quality under all operating condition of the machine without use of external harmonic filters. Method of switching optimization and predicted performance of the drive are presented. Experimental results from a lab-scale prototype are provided to validate the concept.

This paper presents digital control schemes for control of two permanent magnet (PM) machines in an integrated traction and air-conditioning compressor drive system for automotive applications. The integrated drive system employs a five-leg inverter to power a three-phase traction PM motor and a two-phase compressor PM motor by tying the common terminal of the two-phase motor to the neutral point of the three-phase motor. Compared to a standalone three-phase or two-phase inverter, it eliminates one phase leg and shares the control electronics between the two drives, thus significantly reducing the component count of the compressor drive. To demonstrate that the speed and torque of the two PM motors can be controlled independently, a control strategy was implemented in a digital signal processor, which includes a rotor flux field orientation based control (RFOC) for the three-phase motor, a similar RFOC and a position sensorless control in the brushless dc (BLDC) mode for the two-phase motor. Control implementation issues unique to a two-phase PM motor are also discussed. Test results with the three-phase motor running in the ac synchronous (ACS) mode while the two-phase motor either in the ACS or the BLDC mode are included to verify the independent speed and torque control capability of the integrated drive.

Closed-loop control of an integrated dual-inverter which is able to drive two permanent magnet motors independently is presented and evaluated experimentally. By utilizing the neutral point of the main traction motor, only two inverter legs are needed for the two-phase auxiliary motor. A modified field oriented control scheme for this integrated inverter was introduced and employed in real-time control. Experimental results show that the inverter is able to control two drives independently. An integrated, component-count-reduced drive is achieved

This paper focuses on the detection of rotor eccentricity faults in induction motors supplied by a vector-controlled drive. With the vector control, the motor and drive operate in a closed-loop fashion. Their behavior is coupled and their fault harmonics interact, which add significant challenges to fault detection above and beyond those faced by conventional line-connected machines. In this paper, the influence of drive controller and mechanical load on the fault detection is investigated, and a reliable detection scheme is proposed. In addition, a new direct time-stepping finite element model is introduced to incorporate the effects of magnetic nonlinearity into simulation. The simulation and experimental results are presented to validate the feasibility of the new detection method.