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Prostate cancer (PCa) is the second most commonly diagnosed cancer in men. The Rac1-GTP inhibitor NSC23766 has been shown to suppress PCa growth. However, these therapies have low tumor-targeting efficacy in vivo. Therefore, it is essential to produce a drug delivery system that specifically targets the tumor site. Herein, novel L-phenylalanine-based poly(ester amide) (Phe-PEA) polymers were synthesized and loaded with NSC23766 (NSC23766@8P6 NPs), which had a small particle size (162.3±6.7 nm) and high NSC23766 loading (8.0±1.1%) with a more rapid release of NSC23766 at pH 5.0. In vitro cellular uptake and cytotoxicity assays demonstrated that NSC23766@8P6 NPs were rapidly taken up by PC3 cells and showed significant effects of PCa cell proliferation inhibition and G2/M phase arrest. Furthermore, in vivo studies using PC3-bearing mice demonstrated that NSC23766@8P6 NPs delivered by intravenous injection not only increased the drug concentration with prolonged retention (96 h) at the tumor site, but also inhibited tumor growth and induced apoptosis. In conclusion, we have discovered that NSC23766@8P6 NPs can serve as a delivery system that targets the tumor site and is therefore a promising therapeutic approach for PCa treatment.

High-fidelity life-cycle coupling simulations are attractive for increasing reactor power, increasing the fuel burnup and prolonging the reactor lifetime, which makes reactors much more economical. In this work, the continuous energy Reactor Monte Carlo code RMC was coupled to the subchannel code CTF. With the great support of the high-performance computing techniques, the coupled codes were then used to analyze VERA benchmark Problem 9 for the depletion of the fuel and burnable absorbers in a typical 18-month fuel cycle. Existing Monte Carlo burnup codes suffer from instabilities caused by spatial xenon oscillations. Therefore, a xenon equilibrium correction based on a simplified xenon-iodine burnup chain was used to restrain the spatial xenon oscillations and to improve simulation stability. The neutronics and thermal-hydraulics coupling convergence were investigated in terms of power distribution and K eff . The power distribution and K eff variations show that the neutronics/thermal-hydraulics coupling converges in the third iteration. To verify the neutronics/thermal-hydraulics coupling, the critical boron search algorithm and equilibrium xenon correction method, RMC/CTF solutions to a nominal flow and power critical calculation, VERA Benchmark Problem 7, were compared with the VERA reference solutions (MPACT/CTF) and MC21/CTF. The maximum relative difference of radial assembly power between this work and reference solutions was 2.8%. For the VERA Benchmark Problem 9, the measured critical boron concentrations were provided to validate coupling codes. The critical boron concentration prediction by RMC/CTF is consistent with the measured boron concentrations with absolute errors within 20 ppm, which is about 200 pcm in reactivity. The RMC/CTF solution for VERA Core Physics Benchmark Problem 9 is the first published coupled Monte Carlo neutronics/subchannel thermal-hydraulics solution for this problem.

The freckle formation and evolution in directionally solidified single-crystal specimens with different thicknesses and abruptly expanding rectangular cross-section were investigated at different withdrawal rates. The microstructure was studied by optical microscope (OP) and scanning electron microscope (SEM), and the crystallographic orientation in freckle areas was characterized by electron backscattered diffraction (EBSD). The experimental results showed that the freckle was the most severe in specimens with a thickness of 10 mm at the same withdrawal rate, and the freckle chain was observed to form below an abruptly expanding cross-section ended at the expanding step. It was found that freckles formed exclusively on the edges of casting facing the central sprue of the shell mould. Findings reveal that freckles tend to form at the highest position of the mushy zone, mainly due to the thermosolutal convection and the radial flow caused by feeding behavior in the mushy zone. The freckle formation is pronounced at a low withdrawal rate, and can further generate stray grains.

To evaluate the value of pre-stenting and early post-stenting (

The evolution of the crystallographic orientation and the microstructures in triangular adapters of grain continuators (GCs) with different flare angles and thicknesses prepared by a 3rd-generation single crystal (SX) superalloy were investigated under different withdrawal rates. The microstructures were observed by an optical microscope and the crystallographic orientation of the GCs was measured by electron backscatter diffraction (EBSD). The directional solidification process was simulated by a commercial simulation software ProCAST. The experimental results showed that the [001] misorientation between both sides of the GCs at top cross section increased with the increasing of the flare angle, the thickness of specimens, and the withdrawal rate. These phenomena were attributed to the changing of the isotherm morphology in the mushy zones and the velocity of the solidification front. As for a low flare angle, the freckle defect formed at one side of specimens under the withdrawal rate of 1 mm/min. With the increasing of flare angle, the freckle defect cannot be found at the same position of the specimens. The formation mechanisms of freckle defect in the triangular adapters of GCs were further discussed.

In this study, the effect of the thickness of a silica-based ceramic core on its creep deformation, either in air or under vacuum, was studied. Specimens with different thicknesses after sintering were heated to 1550 °C and by maintaining the same temperature for 40, 70 or 100 min. Scanning electronic microscopy (SEM) was employed to observe the surface microstructures and fracture morphologies of the samples. X-ray diffraction (XRD) was used to characterize the phases that formed after creep deformation. The 3D distribution of micropores and the porosities of the specimens at different states were tested by X-ray computerized tomography (XCT). The experimental results show that the effect of the thickness of the specimen on the creep deformation was notably different under different atmospheres. The creep deformation of samples with the same thicknesses under vacuum atmosphere was clearly higher than the deformation in air. In air, the creep resistance was slightly affected by the thickness of the specimen. However, the creep deformation was significantly affected by the thickness of the specimen under vacuum. The creep resistance of the 4-mm-thick specimen is noticeably higher than that of the 0.5-mm-thick specimens. The creep rate of the 0.5-mm-thick specimen is linear with the porosity of the surface layer and higher compared to the 4-mm-thick specimen, which exhibited non-linear behaviour. Reactive micropores were formed on the surface layer of these specimens under vacuum. The volume fraction of the micropores increased with increasing creep time, which resulted in the different characterization of creep for specimens with different thicknesses under vacuum.

As high-resolution nuclear reactor simulations have become increasingly popular, the repeated structure geometry employed in Monte Carlo (MC) transport codes requires modification in order to represent nonrepetitive parameters, such as the temperature distribution and material densities in burnup. To address this issue, a hash mapping method using cell vectors is developed to build a one-to-one relationship between the cells and the parameters. In this method, the shift hash function is proposed to calculate the hash values; this function is intuitive and does not lead to hash collisions. Then, the 〈 cell vector → hash value → cell parameter 〉 mapping relationship is established to rapidly obtain the cell information. A reconversion method for the shift hash value is also developed to convert the hash value back to the cell vector. The hash mapping method is implemented in an MC code (RMC) and is integrated with the burnup, thermal–hydraulic feedback, and neighbor cell capabilities. A comparison between the hash mapping method and the usual methods shows a clear efficiency enhancement, with a speedup ranging from 1.06 to 1.64. Implementing the reconversion method saves over 100 megabytes of memory for the neighbor cell capability.

The power grid system is one of the most important and complex infrastructure systems in our society. Catastrophic blackouts caused by cascading failures, however, still occur and lead to devastating effects. Here, for the first time, we investigate the robustness of the Chinese power grid (CPG) system under various attack and defense scenarios by considering cascading failures. The simulation results illustrate that the effect of the loading level of the power grid network has a large influence on the cascading process. When the initial load of the edge is smaller (α ≤ 1.6), the ascending order strategy of the edge collective influence is the most effective attack strategy for triggering cascading failures over the CPG network. While when the initial load of the edge is larger (α≥1.6), the high load strategy appears to outperform the other strategies. To protect the national power grid from cascading failure, two approaches can be adopted: one approach is to improve the network load capacity, and the other approach is to protect the critical edges. The efforts needed to improve the cascading robustness of the CPG network within these two approaches are quantified. Our results can guide protective measures to avoid large cascading failures and are useful for the design of a robust national power grid network.

Freckles are detrimental solidification defects in Ni-based single-crystal superalloy castings that are formed during directional solidification. However, the evolution of freckles into sliver defects has rarely been reported, and the mechanism of this evolution is unclear. In this study, the evolution of freckles into slivers in the extended zone of casting was established to be the deformation of dendrites induced by the thermal contraction stress in the freckle channel. The morphology of the mushy zone was simulated using ProCAST, which indicated that freckles were formed at the highest position of the mushy zone. During the initiation of the slivers, deformation occurred at the freckle channel, indicating that the thermal contraction stress was a result of the solidification shrinkage of solute-rich liquid. The misorientation from the initial freckle grains to the slivers ranged from 15° to 57°. In addition, the orientation and ability of dendrite branching are crucial for the extension of the sliver dendrites.

In this work, the capability of computing adjoint-weighted kinetic parameters, including effective delayed neutron fraction and neutron generation time, was implemented in the Reactor Monte Carlo (RMC) code based on the iterated fission probability (IFP) method. Three algorithms, namely, the Non-Overlapping Blocks (NOB) algorithm, the Multiple Overlapping Blocks (MOB) algorithm and the superhistory algorithm, were implemented in RMC to investigate their accuracy, computational efficiency and estimation of variance. The algorithms and capability of computing kinetic parameters in RMC were verified and validated by comparison with MCNP6 as well as experimental results through a set of multi-group problems and continuous-energy problems.

Sensitivity and uncertainty analyses of generalized response functions are essential for nuclear designs because they provide useful information about how changes in the input parameters influence the neutronics response. Several methods have been developed to compute generalized sensitivity coefficients for nuclear data. One method is the GEneralized Adjoint Responses in Monte Carlo (GEAR-MC) method which can be used to analyze the sensitivity coefficients of reaction rate ratios. However, this method requires the generalized adjoint function to estimate the sensitivity coefficients. The generalized adjoint function can be calculated using a method like the iterated fission probability (IFP) method which has a huge memory requirement. In this paper, the superhistory-based GEAR-MC method is developed to reduce the huge memory requirement induced by calculating the generalized adjoint function. This newly developed superhistory-based GEAR-MC method is found to be accurately predict the sensitivities of the reaction rate ratios for the Godiva, Flattop and the UAM TMI PWR pin cell benchmark problems. The calculations also show that the memory usage of the superhistory-based GEAR-MC method is 98% less than for the traditional power iteration-based GEAR-MC method. In addition, it is shown that the superhistory-based GEAR-MC method will increase the runtime and this increase is not totally linearly proportional to the number of inner generations in each superhistory for all test cases. Moreover, the equivalence of GEAR-MC method and first-order differential operator method are also proved in this paper.

The Virtual Environment for Reactor Applications (VERA) Core Physics Benchmark Progression problems #1 to #10 based on the 17 × 17 Pressurized Water Reactor (PWR) Watts Bar Unit 1 designed by Westinghouse have been proposed by the Consortium for Advanced Simulations of Light Water Reactors (CASL) as core physics benchmarks. These problems were selected to assist nuclear software and methods developers to develop the capabilities needed to accurately model nuclear power reactors. These problems have 10 different conditions ranging from a simple 2D pin cell to the full core time-dependent depletion. VERA Problem #8, Physical Reactor Flux Maps, describes the first 48 h of a reactor startup with the power gradually increasing from 0% to 100% including the control rod movements which must be considered. This problem was solved in this study using the continuous energy Monte Carlo code RMC coupled with the subchannel thermal-hydraulics code CTF in a hybrid computational strategy. The effects of axial-layering on the solutions were studied with the model divided into 10 layers in the axial direction with the analyses considering both the cost and the accuracy with VERA Problem #8 simulated on the Tianhe II supercomputer. A large number of particles was simulated to get a reliable solution with the mean uncertainty in the power distribution reduced to about 2.6% for all the 526,640 burnup regions for each iteration between RMC and CTF. The eigenvalue trajectory of the critical boron concentration during the startup was provided with the predicted k eff which differs from the common continuous decline. The RMC/CTF code also gives a 3D view of the relative power density distribution and the relative uncertainty distribution at three typical time points and the subchannel outlet temperatures whose peak locations are consistent with the radial power distribution. The RMC/CTF solution is the first published coupled Monte Carlo neutronics/subchannel thermal hydraulics solutions for Problem #8.

Objective To investigate current status of diagnosis and treatment of bladder cancer in China. Methods A database was generated by Chinese Bladder Cancer Consortium (CBCC). From January 2007 to December 2012, 14,260 cases from 44 CBCC centers were included. Data of diagnosis, treatment and pathology were collected. Results The average age was 63.5 year-old and most patients were male (84.3%). The most common histologic types were urothelial carcinoma (91.4%), adenocarcinoma (1.8%), and squamous carcinoma (1.9%). According to 1973 and 2004 WHO grading system, 42.0%, 41.0%, and 17.0% of patients were grade 1, 2, and 3, and 16.0%, 48.7%, and 35.3% of patients were papillary urothelial neoplasms of low malignant potential, low, and high grade, respectively. Non-muscle invasive bladder cancer (NMIBC) and muscle invasive bladder cancer (MIBC) were 25.2% and 74.1%, respectively (0.8% not clear). Carcinoma in situ was only 2.4%. Most patients were diagnosed by white-light cystoscopy with biopsy (74.3%). Fluorescence and narrow band imaging cystoscopy had additional detection rate of 1.0% and 4.0%, respectively. Diagnostic transurethral resection (TUR) provided detection rate of 16.9%. Most NMIBCs were treated with TUR (89.2%). After initial TUR, 2.6% accepted second TUR, and 45.7%, 69.9%, and 58.7% accepted immediate, induced, and maintenance chemotherapy instillation, respectively. Most MIBCs were treated with radical cystectomy (RC, 59.7%). Laparoscopic RCs were 35.1%, while open RC 63.4%. Extended and standard pelvic lymph node dissection were 7% and 66%, respectively. Three most common urinary diversions were orthotopic neobladder (44%), ileal conduit (31%), and ureterocutaneostomy (23%). Only 2.3% of patients accepted neo-adjuvant chemotherapy and only 18% of T3 and T4 patients accepted adjuvant chemotherapy. Conclusion Disease characteristics are similar to international reports, while differences of diagnosis and treatment exist. This study can provide evidences for revisions of the guideline on bladder cancer in China.

The purpose of this paper is to provide a hierarchical and active fault location method in neutral point non-effectively grounded loop distribution network. It analyzes the distribution of loop closing zero-sequence current with single-phase grounding (SPG) fault occurring in two different topologies. According to the variations characteristics of steady loop closing zero-sequence current, fault section can be determined. Then precise SPG fault position can be got using Discrete Wavelet Transform (DWT) and Support Vector Machine (SVM) technology. Even if the fault point cant be located at the first time, the method can still work by repeating the process till the accurate fault position is located. More than 115,200 study cases are simulated on the simulation platform built on PSCAD/EMTP. The results indicate that the proposed fault location method is effective and robust for neutral point non-effectively grounded loop distribution network.

Robot-assisted radical cystectomy (RARC) is increasingly being used in the management of bladder cancer. Studies comparing RARC and open radical cystectomy (ORC) have reported conflicting results. We conducted a systematic review and meta-analysis of the literature on the efficacy and advantages of RARC compared with ORC.An electronic database search of PubMed, Scopus, and the Cochrane Library was performed up to July 8, 2012. This systematic review and meta-analysis was performed based on all randomized controlled trials (RCTs) and observational comparative studies assessing the two techniques.One RCT, eight studies with prospectively collected data, and four retrospective studies were identified, including 962 cases. Although RARC was associated with longer operative time (p0.001), patients in this group might benefit from less overall perioperative complications (p=0.04), more lymph node yield (p=0.009), less estimated blood loss (p0.001), a lower need for perioperative transfusion (p0.001), and shorter length of hospital stay (p0.001). Positive surgical margins did not differ significantly between techniques. Sensitivity analysis with prospective studies showed similar results to the original analysis, but no significant difference of lymph node yield and length of stay between two techniques.RARC is a mini-invasive alternative to ORC with less overall perioperative complications, more lymph node yields, less estimated blood loss, less need for a perioperative transfusion, and shorter length of stay.