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This paper proposes an efficient decomposition-based optimization framework using adaptive metamodeling for expensive aero-structure coupled wing optimization problems. First, high-fidelity aero-structure coupled analysis method is presented through spatial interpolations of distributed aerodynamic loads and structural deformation. The proposed optimization framework decomposes the original complex coupled optimization problem into 2-D airfoil optimization (i.e., Stage-I) and 3-D wing optimization (i.e., Stage-II) to alleviate the expensive computational costs. In Stage-II, a two-level optimization strategy is tailored to further decompose the 3-D wing optimization into system-level and subsystem-level for dimension reduction. An adaptive response surface method using intelligent space exploration strategy is used to perform optimization tasks involving CFD simulations (i.e., 2-D airfoil optimization and system-level optimization in Stage-II), while sequential quadratic programming is employed to optimize the massive subsystem structure sizing variables. The effectiveness of two-level optimization strategy is validated on a numerical testing problem and a simplified wing optimization case. Finally, the developed models and proposed methods are successfully applied to aero-structure coupled optimization of a high aspect ratio wing. The optimization results demonstrate the effectiveness of the developed aero-structural analysis models and efficiency of the proposed optimization methods.

This paper presents a preview servo-loop speed control algorithm to achieve smooth, accurate, and computationally inexpensive speed tracking for connected automated vehicles (CAVs). Differing from methods neglecting the future road slope and target speed information, the proposed controller focuses on taking advantages of this accessible future information to achieve better speed tracking performance. It integrates the future slope and target speed into an augmented optimal control problem, by solving which we obtain the optimal control law in an analytical form. The brake/ throttle control laws consist of five parts, i.e., three feedback controls of system states and two feedforward items-preview of road slope and preview oftarget speed. This controller and its degenerate form, i.e., a classic PID, are implemented and applied to our automated vehicle platform, a Hybrid Lincoln MKZ. Experimental results show three major benefits of the proposed control-lower speed tracking errors, more gentle operations, and smoother brake/throttle behaviors.

Coupled vibration of a radially polarized piezoelectric cylindrical transducer is analyzed with the mechanical coupling coefficient method. The method has been utilized to analyze the metal cylindrical transducer and the axially polarized piezoelectric cylindrical transducer. In this method, the mechanical coupling coefficient is introduced and defined as the stress ratio in different directions. Coupled vibration of the cylindrical transducer is regarded as the interaction of the plane radial vibration of a ring and the longitudinal vibration of a tube. For the radially polarized piezoelectric cylindrical transducer, the radial and longitudinal electric admittances as functions of mechanical coupling coefficients and angular frequencies are derived, respectively. The resonance frequency equations are obtained. The dependence of resonance frequency and mechanical coupling coefficient on aspect ratio is studied. Vibrational distributions on the surfaces of the cylindrical transducer are presented with experimental measurement. On the support of experiments, this work is verified and provides a theoretical foundation for the analysis and design of the radially polarized piezoelectric cylindrical transducer.

Nitrogen-doped carbon nanotubes synthesized from a mixture of ferrocene, xylenes, and acetonitrile using chemical vapor deposition technique comprise compartmented hollow structures resembling stacked cups. Separating stacked nitrogen-doped carbon nanotube cups (NCNCs) into individual cups is an attractive way to further manipulate their morphology, providing additional opportunities for applications of NCNCs. Here we demonstrate an effective, simple, and low-cost separation method to obtain individual NCNCs around 180 nm in length, by sonicating as-synthesized stacked NCNCs in concentrated KCl solution. Another advantage of this technique is that it is highly selective to the separation of adjacent NCNCs and capable of preserving the surface structure and functionalities of stacked NCNCs. Here we demonstrate that the presence of potassium ions is vital for the separation and we hypothesize that the separation mechanism involves a partial intercalation that facilitates the separation of NCNCs.

Long non-coding RNAs (lncRNAs), which have emerged as important regulatory RNA molecules that have been implicated in carcinogenesis and cancer progression, may also serve as novel potential biomarkers for cancer diagnosis and prognosis. Our previous analysis has identified the lncRNA GHRLOS, the ghrelin antisense strand non-coding RNA gene, as one of the hub genes in the co-expression network of differentially expressed lncRNAs/mRNAs in colorectal cancer (CRC). Here, we further evaluate the expression of GHRLOS in CRC and explore its clinical significance. The expression of GHRLOS in 366 pairs of CRC and adjacent non-cancerous tissues was detected by quantitative RT-PCR assays. The results showed that the expression level of GHRLOS was significantly lower in CRC tissues than in matched non-cancerous tissues (P < 0.001). Decreased GHRLOS expression was observed in 54.4% (199/366) of cases, and was significantly correlated with the occurrence of lymph node metastasis (P = 0.033) and distant metastasis (P = 0.005). A Kaplan-Meier analysis demonstrated that decreased GHRLOS expression contributed to poor disease-free survival (log-rank test, P < 0.001) and overall survival (log-rank test, P < 0.001). Moreover, a multivariate Cox regression analysis revealed the decreased expression of GHRLOS as an independent prognostic marker of poor outcomes [disease-free survival: hazard ratio (HR) = 2.02, 95% confidence interval (CI) = 1.42-3.88; overall survival: HR = 1.96, 95% CI = 1.34-2.86] in CRC patients. In conclusion, our data suggest that the lncRNA GHRLOS might serve as a candidate biomarker of tumor metastasis and a prognostic indicator in CRC.

Previous studies that assessed the relationship between obesity, overweight, and survival in colorectal cancer (CRC) have provided conflicting results. Therefore, we quantitatively summarized existing evidence to estimate the association between obesity/overweight and overall survival (OS) in CRC patients and explored potentially important sources of variability. Eligible studies were identified via PubMed and EMBASE searches. The summary hazard ratio (sHR) was estimated using a fixed-effects or random-effects model according to the heterogeneity between the studies. Meta-regression and subgroup analyses were performed to explore potential sources of heterogeneity. A total of 29 eligible studies, with 51,303 CRC patients, were finally included. The overall analysis showed worse OS among obese patients [sHR 1.10, 95 % confidence intervals (CI) 1.06–1.15], but not among overweight patients (sHR 0.92, 95 % CI 0.86–1.00), than in normal-weight patients. Considerable heterogeneity was observed across studies, which was primarily attributed to the timing of body mass index (BMI) assessment (meta-regression p

For optimized operation and safety consideration, a Thermal Management System (TMS) is consequential for a battery pack. For example, during fast charging in hot climates the cooling system is needed to remove the extra heat generated by the cells to avoid thermal run away and explosion. On the other hand, during fast charging in a cold weather, the TMS should add heat to the cells to make it possible to charge the battery to 80% SOC without serious damage and degradation (such as Li plating at high rates and low temperatures). It is recommended by battery manufacturers that the batteries should not be charged beyond the range of 20 to 40 , especially at higher rates mainly because of cell degradation and safety. However, pack designers often do not consider the effects of TMS design on the cell degradation and lifetime and primarily focus on safety issues. Different commonly used TMS designs for automotive industry are basically heat exchanger systems located on the bottom or top of the battery pack, or around the individual cells inside the pack (see Fig. 1), so heat can be released or added when necessary. The temperature of the cells in the pack can be controlled during charge and discharge for better operation, minimized degradation, and safety issues. The main problem with these systems is that sometimes the TMS introduces non-uniform temperature through the cell (normal to the TMS plate) for bottom and top cooling and in radial direction for side cooling that in turn induces other types of non-uniformities such as non-uniform current density, local state of charge, and Li plating, resulting in a non-uniform degradation. The main objective of this work is to understand the effects of different TMS designs on the amount of Li plating and non-uniform behavior by a combination of an electrochemical (EC) and a thermal (T) model or an ECT model. In order to capture non-uniform behavior, we consider three regions in the z direction for bottom cooling design, based on our previous work [1], as shown in Fig. 2. For side cooling design, three regions are considered in the r direction in a way that the regions’ volumes are equivalent. Due to the shared current collectors of all regions, the regions are treated as parallel connected cells and have similar voltage. According to the Ohm’s law, local current densities are controlled by varied internal resistance of each region (V=IR). The resistance of each region may change by SOC, temperature, transport properties, and microstructure of each regions [2], however in this work the focus is non-uniform temperature due to different TMS designs rather than a non-uniform microstructure[1-3]. The non-uniform temperature resulting from a particular TMS design effects non-uniform resistance and in-turn non-uniform current density. Due to the fact that temperature, current density, and SOC are all important factors that affect the amount of Li plating in each region, it is not easy to predict the amount and non-uniformity degree of Li plating in a cell with bottom, top, or side cooling system during fast charging. The developed ECT model in COMSOL Multiphysics can provide a real insight into this important concept of non-uniform degradation that should be taken into consideration by pack and TMS designers. [1] M.M. Forouzan, B.A. Mazzeo, D.R. Wheeler, J. Electrochem. Soc., 165 (2018) A2127-A2144. [2] J.E. Vogel, M.M. Forouzan, E.E. Hardy, S.T. Crawford, D.R. Wheeler, B.A. Mazzeo, Electrochimica Acta, (2018). [3] M.M. Forouzan, M. Wray, L. Robertson, D.R. Wheeler, J. Electrochem. Soc., 164 (2017) A3117-A3130. Figure 1

Previous studies have documented that brands are vulnerable to negative spillover caused by scandalised brands from the same countries. However, little is known about how individual-level perceived psychic distance (PD) influences the likelihood of spillover occurring. PD refers to individuals' perception of dissimilarities between their home country (or region) and foreign countries (regions). The results from the two experiments indicated that PD improves the likelihood of spillover towards brands from the same region. When PD is high, a brand scandal is more likely to spillover to brands from the same region of origin (ROO) versus those from different ROO. However, when the PD is low, a brand scandal is unlikely to spillover, no matter whether the ROO is the same or not. The results also reveal the moderated mediating role of perceived brand similarity.

Nitrogen-doped and undoped carbon nanotubes (CNTs) were synthesized from ferrocene, nickelocene, and cobaltocene metal catalysts. Electrochemical testing for an oxygen reduction reaction (ORR) showed that nitrogen-doped CNTs synthesized from ferrocene had improved catalytic activity while nanotubes synthesized from nickelocene and cobaltocene, doped with a comparable amount of nitrogen and having similar stacked-cups structure as nitrogen doped CNTs from ferrocene, had a performance only slightly better than that of undoped CNTs. Ferrocene-based nitrogen-doped CNTs also demonstrated similar long-term stability and higher CO tolerance compared to Pt/C catalyst. Detailed ORR mechanisms were also studied and carbon nanomaterials showed different ORR processes as a result of the metal catalyst utilized in the chemical synthesis. Nitrogen-doped and undoped CNTs synthesized from nickelocene show a preferential 4-electron process as compared to materials synthesized from ferrocene and cobaltocene. We believe tha...

Metal-graphitic interfaces formed between metal nanoparticles (MNPs) and carbon nanotubes (CNTs) or graphene play an important role in the properties of such hybrid nanostructures. This Perspective summarizes different types of interfaces that exist within the metal-carbon nanoassemblies and discusses current efforts on understanding and modeling the interfacial conditions and interactions. Characterization of the metal-graphitic interfaces is described here, including microscopy, spectroscopy, electrochemical techniques, and electrical measurements. Recent studies on these nanohybrids have shown that the metal-graphitic interfaces play critical roles in both controlled assembly of nanoparticles and practical applications of nanohybrids in chemical sensors and fuel cells. Better understanding, design, and manipulation of metal-graphitic interfaces could therefore become the new frontier in the research of MNP/CNT or MNP/graphene hybrid systems.

Single-walled carbon nanotube (SWCNT) networks deposited from a purple single chirality (6,5) SWCNT aqueous solution were electrically characterized as pure semiconductors based on metal/semiconductor/metal Schottky contacts using both complex instruments and a portable device. Both air-stable PMOS (p-type metal-oxide-semiconductor) and NMOS (n-type metal-oxide-semiconductor, resembling amorphous silicon) thin film transistors were fabricated on (6,5) SWCNT in large scale showing the characteristics of fA off current and ION/IOFF ratio of1 × 10(8). CMOS (complementary metal-oxide-semiconductor) SWCNT inverter was demonstrated by wire-bonding PMOS (6,5) SWCNT TFT and NMOS (6,5) SWCNT TFT together to achieve the voltage gain as large as 52.

Chronic inflammation, promoted by an upregulated NF-kappa B (NF-κB) pathway, has a key role in Duchenne muscular dystrophy (DMD) patients' pathogenesis. Blocking the NF-κB pathway has been shown to be a viable approach to diminish chronic inflammation and necrosis in the dystrophin-defective mdx mouse, a murine DMD model. In this study, we used the recombinant adeno-associated virus serotype 9 (AAV9) carrying an short hairpin RNA (shRNA) specifically targeting the messenger RNA of NF-κB/p65 (p65-shRNA), the major subunit of NF-κB associated with chronic inflammation in mdx mice. We examined whether i.m. AAV9-mediated delivery of p65-shRNA could decrease NF-κB activation, allowing for amelioration of muscle pathologies in 1- and 4-month-old mdx mice. At 1 month after treatment, NF-κB/p65 levels were significantly decreased by AAV gene transfer of p65-shRNA in the two ages of treatment groups, with necrosis significantly decreased compared with controls. Quantitative analysis revealed that central nucleation (CN) of the myofibers of p65-shRNA-treated 1-month-old mdx muscles was reduced from 67 to 34%, but the level of CN was not significantly decreased in treated 4-month-old mdx mice. Moreover, delivery of the p65-shRNA enhanced the capacity of myofiber regeneration in old mdx mice treated at 4 months of age when the dystrophic myofibers were most exhausted; however, such p65 silencing diminished the myofiber regeneration in young mdx mice treated at 1 month of age. Taken together, these findings demonstrate that the AAV-mediated delivery of p65-shRNA has the capacity to ameliorate muscle pathologies in mdx mice by selectively reducing NF-κB/p65 activity.

Here we performed amperometric detection of hydrogen peroxide (H2O2) using single-walled carbon nanotubes (SWNTs), chemically converted graphene (CCG), and sulfonated CCG (CCG-S) decorated with Pt nanoparticles (NPs). Although all three systems demonstrated similar detection limits for H2O2, compared to the other two nanomaterials, Pt-SWNTs provided a higher sensitivity with only half of the Pt amount. This result was consistent with cyclic voltammetry, electrochemical impedance spectroscopy, and field-effect transistor measurements. We attribute the higher sensitivity of Pt-SWNTs to both the surface roughness of the electrode and the intimate contact between Pt NPs and one-dimensional nanostructures (SWNTs) versus two-dimensional nanostructures (graphene).

We report the electrochemical properties and performance of Pt-decorated carbon nanotube (Pt-CNT) catalysts for long-term operation in phosphoric acid fuel cells (PAFCs). Electrochemical measurements of Pt-CNT catalysts including cyclic voltammetry, rotating ring disk electrode voltammetry, and electrochemical impedance spectroscopy were conducted to evaluate the catalyzed oxygen reduction reaction (ORR). Furthermore, we tested the long-term performance of the Pt-CNT catalysts in 2′′ × 2′′ PAFC cathodes operating at 190 °C in 85% H3PO4 for extended periods (up to 240 days). Lifetime studies show that electrodes containing the Pt-CNT catalysts were approximately 20 times more stable than conventional Pt-C catalyst materials, even with a substantially thinner catalyst layer. This finding of the enhanced Pt-CNT catalyst stability bodes well for possible personal electronics or automotive applications, where catalyst longevity is an essential requirement.

We examine a supply chain with one small supplier with capital constraint and one retailer with sufficient capital and bargaining power. The supplier does not possess enough credit to get bank loan independently. So when no financing service is viable, the supplier’s production quantity is restricted, which will reduce the whole supply chain efficiency. The retailer may help the early production by providing reverse factoring or direct prepayment. When given the choice between the two credit types, the unique equilibrium is reverse factoring when the retailer can reach a high credit term, but is prepayment otherwise. Our analysis further suggests that the equilibrium region of prepayment financing shrinks as the retailer can default on certain proportion of the wholesale contract.

We demonstrate a facile synthesis of different nanostructures by oxidative unzipping of stacked nitrogen-doped carbon nanotube cups (NCNCs). Depending on the initial number of stacked-cup segments, this method can yield graphene nanosheets (GNSs) or hybrid nanostructures comprised of graphene nanoribbons partially unzipped from a central nanotube core. Due to the stacked-cup structure of as-synthesized NCNCs, preventing complete exposure of graphitic planes, the unzipping mechanism is hindered, resulting in incomplete unzipping; however, individual, separated NCNCs are completely unzipped, yielding individual nitrogen-doped GNSs. Graphene-based materials have been employed as electrocatalysts for many important chemical reactions, and it has been proposed that increasing the reactive edges results in more efficient electrocatalysis. In this paper, we apply these graphene conjugates as electrocatalysts for the oxygen reduction reaction (ORR) to determine how the increase in reactive edges affects the electrocatalytic activity. This investigation introduces a new method for the improvement of ORR electrocatalysts by using nitrogen dopants more effectively, allowing for enhanced ORR performance with lower overall nitrogen content. Additionally, the GNSs were functionalized with gold nanoparticles (GNPs), resulting in a GNS/GNP hybrid, which shows efficient surface-enhanced Raman scattering and expands the scope of its application in advanced device fabrication and biosensing.

In this paper a new texture operator based on Local Binary Patterns (LBP) was proposed for face recognition called Circle-Block Local Binary Patterns (CB-LBP). The mean gray values of a circle block pixels are calculated to achieve macroscopic feature extraction. Our method was compared with the LBP-based patterns tested on Extended Yale B face image databases. Experimental results show the effectiveness of the proposed method.

We present a scheme to generate the third harmonic in the fundamental mode using microfibres, by introducing a counter-propagating pump field to partly compensate the phase mismatch and thus enhance the harmonic conversion efficiency.

Because of their unique stacked, cup-shaped, hollow compartments, nitrogen-doped carbon nanotube cups (NCNCs) have promising potential as nanoscale containers. Individual NCNCs are isolated from their stacked structure through acid oxidation and subsequent probe-tip sonication. The NCNCs are then effectively corked with gold nanoparticles (GNPs) by sodium citrate reduction with chloroauric acid, forming graphitic nanocapsules with significant surface-enhanced Raman signature. Mechanistically, the growth of the GNP corks starts from the nucleation and welding of gold seeds on the open rims of NCNCs enriched with nitrogen functionalities, as confirmed by density functional theory calculations. A potent oxidizing enzyme of neutrophils, myeloperoxidase (MPO), can effectively open the corked NCNCs through GNP detachment, with subsequent complete enzymatic degradation of the graphitic shells. This controlled opening and degradation was further carried out in vitro with human neutrophils. Furthermore, the GNP-corked NCNCs were demonstrated to function as novel drug delivery carriers, capable of effective (i) delivery of paclitaxel to tumor-associated myeloid-derived suppressor cells (MDSC), (ii) MPO-regulated release, and (iii) blockade of MDSC immunosuppressive potential.

To make the allocation of hardware resources more reasonable and flexible on private infrastructure as a service cloud platform in enterprises, approving system described in this paper provides an efficient solution. Each user has a basic quota. If users need to get more resources, the reason must be given to apply. According to the performance of the eventually practice on OpenStack, this system can prevent users from allocating more hardware resources than they need, and save the hardware resources. We implemented the approving system on OpenStack, and the resource of server was saved.

The ability to accurately measure real-time pH fluctuations in-vivo could be highly advantageous. Early detection and potential prevention of bacteria colonization of surgical implants can be accomplished by monitoring associated acidosis. However, conventional glass membrane or ion-selective field-effect transistor (ISFET) pH sensing technologies both require a reference electrode which may suffer from leakage of electrolytes and potential contamination. Herein, we describe a solid-state sensor based on oxidized single-walled carbon nanotubes (ox-SWNTs) functionalized with the conductive polymer poly(1-aminoanthracene) (PAA). This device had a Nernstian response over a wide pH range (2–12) and retained sensitivity over 120 days. The sensor was also attached to a passively-powered radio-frequency identification (RFID) tag which transmits pH data through simulated skin. This battery-less, reference electrode free, wirelessly transmitting sensor platform shows potential for biomedical applications as an implantable sensor, adjacent to surgical implants detecting for infection.

Field orientation control (FOC) of induction machines has permitted fast transient response by decoupled torque and flux control. However, field orientation detuning caused by parameter variations is a major difficulty for indirect FOC methods. Traditional probability density function (PID) controllers have trouble meeting a wide range of speed tracking performance even when proper field orientation is achieved. PID controller performance is severely degraded when detuning occurs. This paper presents a fuzzy logic design approach that can meet the speed tracking requirements even when detuning occurs. Computer simulations and experimental results obtained via a general-purpose digital signal processor (DSP) system are presented.

Material productivity, design preciseness, and time to market are becoming critical in motor manufacturing and can be improved by detailed system design analysis and simulation within manufacturing tolerance. Design by analysis and simulation of switched reluctance motor (SRM) systems and the development method of a new design software are the subjects of this paper, with a focus on the main difficulties. The modeling of geometric, electromagnetic, control, mechanical, and thermal concerns is presented. The electromagnetic approaches include lumped-parameter analysis, finite-element analysis, and boundary-element analysis. The aspects of the study include the following: magnetization curves; controller characterization; system simulation; performance prediction; control system dynamics; vibration modes and frequencies; radial magnetic forces, stresses, and vibrations; and dynamic heat distribution and transfer.

Nitrogen-doped carbon nanotubes consist of many cup-shaped graphitic compartments termed as nitrogen-doped carbon nanotube cups (NCNCs). These as-synthesized graphitic nanocups from chemical vapor deposition (CVD) method were stacked in a head-to-tail fashion held only through noncovalent interactions. Individual NCNCs can be isolated out of their stacking structure through a series of chemical and physical separation processes. First, as-synthesized NCNCs were oxidized in a mixture of strong acids to introduce oxygen-containing defects on the graphitic walls. The oxidized NCNCs were then processed using high-intensity probe-tip sonication which effectively separated the stacked NCNCs into individual graphitic nanocups. Owing to their abundant oxygen and nitrogen surface functionalities, the resulted individual NCNCs are highly hydrophilic and can be effectively functionalized with gold nanoparticles (GNPs), which preferentially fit in the opening of the cups as cork stoppers. These graphitic nanocups corked with GNPs may find promising applications as nanoscale containers and drug carriers.

A new approach for the systemized optimization of power distribution systems is presented in this paper. Distribution system reliability is modelled in the optimization objective function via outage costs and costs of switching devices, along with the nonlinear costs of investment, maintenance and energy losses of both the substations and the feeders. The optimization model established is multi-stage, mixed-integer and nonlinear, which is solved by a network-flow programming algorithm. A multi-stage interlacing strategy and a nonlinearity iteration method are also designed. Supported by an extensive database, the planning software tool has been applied to optimize the power distribution system of a developing city.

Nonlinear boundary element analysis provides a more accurate and detailing tool for the design of switched reluctance machines than conventional equivalent-circuit methods. Design optimization through more detailed analysis and simulation can reduce development and prototyping costs and time to market. Firstly, magnetic field modeling of an industrial switched reluctance machine by the boundary element method is reported in this paper. Secondly, performance prediction and dynamic simulation of motor and control design are presented. Thirdly, magnetic forces that cause noise and vibration are studied, to include the effects of motor and control design variations on noise in the design process. Testing of such a motor in the NEMA 215-Frame size is carried out to verify the accuracy of modeling and simulation.

A slip power recovery configuration provides an attractive alternative for variable speed drives and generating systems, due to its improved efficiency and low power converter rating. The core component is the doubly-excited machine. First, the authors present a stability analysis of the doubly-excited machine with open-loop voltage control and open-loop current control in the rotor circuit. Possibilities of open-loop control are analyzed. Second, they present a unified model of a high-performance slip power recovery system composed of a field-orientation controlled doubly-excited machine, power converters and a DC bus in the rotor circuit. The stability of this composite system represented by a model is studied. Of special interest is when the system functions as a variable-speed motor drive system or as a variable-speed constant-frequency generating system. >

Field orientation control and fuzzy logic control are designed for variable speed drive systems with a doubly-fed machine in a slip power recovery configuration. Laboratory implementation with a general purpose DSP (digital signal processing) system is described and experimental results are given. High performance potential of a slip power recovery system is realized with these advanced controls, while flexible reactive power control becomes possible, and compared to the ordinary variable speed drives with singly-fed induction machines, power converter rating is reduced.

PIK3CA mutation appears to predict a lack of response to anti-EGFR monoclonal antibody (mAb) treatment in patients with metastatic colorectal cancer (mCRC). However, the predictive value of PIK3CA mutations for survival remains inconclusive. Here, we pooled the data from published studies to estimate the association between PIK3CA mutation and survival outcomes in mCRC patients treated with anti-EGFR mAbs.Studies investigating the association of PIK3CA mutations with clinical survival outcomes of mCRC patients treated with anti-EGFR mAbs were systematically identified. The overall hazard ratio (HR) was estimated by using fixed effect model or random effect model according to heterogeneity between trails.Eight studies that reported survival outcome in 839 mCRC patients were included. In unselected patients, we found that PIK3CA mutations were significantly associated with poorer PFS [8 studies, 839 patients; HR = 1.53; 95 % confidence interval (CI) 1.28-1.84; P0.001] and OS (5 studies; 587 patients; HR = 1.28; 95 % CI 1.05-1.56; P = 0.015). With increased predictive power in KRAS wild-type patients (3 studies; 275 patients), the overall HR for PFS was 2.44 (95 % CI 1.33-4.48; P = 0.004) and was statistically significant. We also observed a worse OS in KRAS wild-type patients with PIK3CA mutations (2 studies; 163 patients; HR = 1.37; 95 % CI 0.80-2.35; P = 0.258), although the result was not statistically significant due to small sample size.PIK3CA mutation is a promising predictive biomarker for poor survival in mCRC patients treated with anti-EGFR mAbs, particularly in KRAS wild-type patients.

Nitrogen doping of carbon nanotubes during chemical vapor deposition synthesis can create unique stacked cup-shaped structures termed as nitrogen-doped carbon nanotube cups (NCNCs). These cups have semielliptical hollow cavities and elevated reactivity which could lead to various applications. In this work, by applying intense ultrasonication to the as-synthesized NCNCs, we demonstrated an effective mechanical method to isolate the individual cups with opened cavities from their stacks. The graphitic structures of the isolated cups and their inherent nitrogen functionalities were characterized by comprehensive microscopic and spectroscopic methods. In particular, we quantitatively determined the existence of amine functionalities on NCNCs and found that they were preferentially distributed at the open edges of the cups, providing localized reactive sites. Further, by thiolating the amine groups with 3-mercapto-propionic acid, we were able to effectively cork the isolated cups by gold nanoparticles with commensurate diameters. These cup-shaped carbon nanomaterials with controlled inner volumes and gold nanoparticle corks could find potential applications as nanoscale reaction containers or drug delivery vehicles.

In computer science, graph is one of the most complex data structures. But graph can be used in research and in bussiness because of its intuitive expression. It is a focus in data mining how to derive the interesting subgraph patterns from a great number of graphs. This article introduces a data mining algorithm based on graph which ueses the graph theory to improve the classic Apriori algorithm. And this algorithm can mine frequent subgraph patterns effectively. Keywordsdata mining; algorithm; graph; Apriori

Doubly excited brushless reluctance machine (DEBRM) has gained much attention in the area of variable-speed constant-frequency generating systems and adjustable speed drives. Two types of reluctance rotor structure, axially laminated and simple salient rotors, are suggested in the DEBRM development. Due to the unconventional pole number combination of the stator and rotor, performance evaluation of the DEBRM with different rotor structures is difficult. A comparison study of two rotor structures of the DEBRM is presented in this paper by finite element analysis. It is shown that by calculating selfand mutual-flux linkage of the dual stator windings as the function of rotor positions, performance of the complicated DEBRM can be evaluated conveniently. Various advantages and disadvantages of the DEBRM associated with the two rotor structures are also discussed. >

The slip power recovery configuration is an attractive scheme of variable speed drive, with high efficiency and low power converter rating; however, high performance control has been difficult. In this paper, novel applications of fuzzy logic for the intelligent control of a slip power recovery system are presented. A direct fuzzy logic controller and an adaptive fuzzy controller, based on model reference adaptive control, are developed and simulated for the doubly-excited induction machine and power converter system. Compared with field orientation control, the intelligent control of a complex slip power recovery system reduces costs and enhances robust and desired performance. >

Single-walled carbon nanotube/polyaniline (SWNT/PAni) nanocomposite with controlled core/shell morphology was synthesized by a noncovalent functionalization approach. Unique electron interactions between the SWNT core and the PAni shell were studied electrochemically and spectroscopically, and superior sensor performance to chemical gases and vapors was demonstrated.

The electrochemical activity of stacked nitrogen-doped carbon nanotube cups (NCNCs) has been explored in comparison to commercial Pt-decorated carbon nanotubes. The nanocup catalyst has demonstrated comparable performance to that of Pt catalyst in oxygen reduction reaction. In addition to effectively catalyzing O(2) reduction, the NCNC electrodes have been used for H(2)O(2) oxidation and consequently for glucose detection when NCNCs were functionalized with glucose oxidase (GOx). Creating the catalysts entirely free of precious metals is of great importance for low-cost fuel cells and biosensors.

Carbon nanotubes with their attractive properties, one-dimensional character, and their large aspect ratio are ideal candidates for a variety of applications including energy storage, sensing, nanoelectronics, among others. We have studied the growth of carbon nanotubes on copper substrates using a nickel thin film as a catalyst. The catalyst was sputtered in a chamber having a base pressure in the ultra-high-vacuum regime. By adjusting the sputtering parameters, the effects of the morphology and the thickness of the nickel catalyst on the growth of carbon nanotubes have also been investigated. Multiple hydrocarbon sources as carbon feedstock (methane, acetylene and xylene) and corresponding catalyst precursors and varying temperature conditions were used during the Chemical Vapor Deposition (CVD) process to understand and best determine the ideal conditions for carbon nanotube growth on copper. Correlation between the thickness of the thin film nickel catalyst and the carbon nanotube diameter is also presented in the study. Characterization techniques used to study the morphology of the CNTs grown on copper include SEM, TEM and HRTEM, Raman Spectroscopy

In this paper, we lay the groundwork for extending our previously developed ASyMTRe architecture to enable constructivist learning for multi-robot team tasks. The ASyMTRe architecture automatically configures schemas within, and across, robots to form the highest utility solution that achieves a given multi-robot team task. We believe that the schema- based approach used in ASyMTRe is a useful abstraction not only for forming heterogeneous coalitions, but also for enabling constructivist learning, in which chunks of schemas that solve intermediate subproblems are learned and then made available for future task solutions. However, the existing ASyMTRe search algorithm for finding configurations of schemas that completely solve given tasks (Centralized ASyMTRe - CA) is not well-suited for identifying useful chunks of schemas that could solve intermediate subtasks that may be useful in the future. Thus, in this current work, we explore an Evolutionary Learning (EL) technique for the offline learning of schema chunks that could be saved and used later in an online search (using the regular CA algorithm) for coalition configurations. However, we do not want to sacrifice solution quality in making use of the evolutionary search technique. Thus, we compare the solutions discovered by the EL algorithm with those that are found using CA, as well as with a third algorithm that randomizes the CA algorithm, called RA. Four different applications in simulation are used to evaluate the EL, CA, and RA techniques. Our results show that the EL approach indeed finds solutions of comparable quality to the CA technique, while also providing the added benefit of learning highly fit partial solutions, or schema chunks, that may be beneficial for future tasks via constructivist learning. We conclude by arguing that the combination of the online CA search for solving current multi-robot tasks can be combined with the offline EL approach that can identify intermediate solutions (or schema chunks) that may be useful for future team tasks. This combination should lead to an overall efficiency improvement for identifying coalition formations, as well as for continual learning.

We introduce the SB-CoRLA architecture that we have developed by extending our previously developed centralized ASyMTRe architecture (CA) to enable constructivist learning for multi-robot team tasks. We believe that the schema-based approach used in ASyMTRe is a useful abstraction for enabling constructivist learning. The CA algorithm only finds complete solutions for the entire team and is not well-suited for identifying useful schema chunks that can be used to find future task solution. Thus, we explore an evolutionary learning (EL) technique for the offline learning of schema chunks. We compare the solutions discovered by the EL algorithm with those that are found using CA, as well as with a third algorithm that randomizes the CA algorithm, called RA. Four different applications in simulation are used to evaluate the techniques. Our results show that the EL approach finds solutions of comparable quality to the CA technique, while also providing the added benefit of learning highly fit schema chunks.

This paper presents an approach for deploying a team of mobile sensor nodes to form a sensor network in indoor environments. The challenge in this work is that the mobile sensor nodes have no ability for localization or obstacle avoidance. Thus, our approach entails the use of more capable "helper" robots that "herd" the mobile sensor nodes into their deployment positions. To extensively explore the issues of heterogeneity in multi-robot teams, we employ the use of two types of helper robots-one that acts as a leader and a second that: 1) acts as a follower and 2) autonomously teleoperates the mobile sensor nodes. Due to limited sensing capabilities, neither of these helper robots can herd the mobile sensor nodes alone; instead, our approach enables the team as a whole to successfully accomplish the sensor deployment task. Our approach involves the use of line-of-sight formation keeping, which enables the follower robot to use visual markers to move the group along the path executed by the leader robot. We present results of the implementation of this approach in simulation, as well as results to date in the implementation on physical robot systems. To our knowledge, this is the first implementation of robot herding using such highly heterogeneous robots, in which no single type of robot could accomplish the sensor network deployment task, even if multiple copies of that robot type were available.

This wok describes novel algorithms for planning the deployment of a large number of navigationally-challenged mobile sensor nodes in known indoor environments. Due to cost and power constraints, our mobile sensor nodes have the ability to move and communicate, but they cannot detect or avoid obstacles or localize to the environment. Additionally, they have only minimal capabilities for detecting other robot team members, through the use of a crude camera. Our deployment process, therefore, uses an assistive navigation technique that enables a more capable leader robot, equipped with a laser rangefinder and a camera, to guide several mobile sensor nodes to their deployment positions. To ensure the successful deployment of the mobile sensor nodes, we have developed an autonomous planning process that plans the positions of the sensor nodes based upon a number of constraints, including maintaining line of sight maximizing visibility coverage, avoiding placement in doorways, minimizing obstruction of corridors, and so forth. Additionally, because of the navigational constraints of simple robots following a leader to these deployment positions, our algorithm also derives two leader waypoints for each sensor position, which on strain the motion of the leader path to the deployment position. These leader