Role of scattering-factor anisotropy in electron, positron, and photon holography

We have studied the angular anisotropy in the scattering factor of electrons, positrons, and photons in solids. We show that as a function of angle, the maximum number of dips in the scattering factor's magnitude and jumps of near π in its phase are related to the angular momenta of the bound and resonance states of the potential. The effect of the scattering factor's anisotropy on low-energy electron and positron holographic wave-front reconstruction is discussed. Applying the variable-axis small-cone method, a good-quality reconstructed image is only possible within angular regions where the scattering factor is near isotropic. Thus the usable window for low-energy electron wave-front reconstruction is element dependent; the window size decreases as the atomic number increases. Positrons, on the other hand, are like photons and are not bound by the potential. For positrons or photons, there is no elemental dependence of the usable window and the entire backscattering regime is suitable for holographic reconstruction. We have established two rules that predict the maximum number of magnitude dips and phase jumps in the scattering factor for any element.published_or_final_versio

Effect of residual stress on spallation of NiCrBSi coating

The impact induced spallation characteristics of two specimens with NiCrBSi coating developed by different treatments are investigated. Two typical spallation patterns corresponding to the two kinds of specimens are observed. Theoretical analysis indicates that the difference in spallation characteristics is due to the residual stress. The initial stress states for the two kinds of specimens are investigated. The outcomes verify that the compressive residual stress within the coating will lead to large buckling region of the coating upon impact

Feedback-induced nonlinearity and superconducting on-chip quantum optics

Quantum coherent feedback has been proven to be an efficient way to tune the dynamics of quantum optical systems and, recently, those of solid-state quantum circuits. Here, inspired by the recent progress of quantum feedback experiments, especially those in mesoscopic circuits, we prove that superconducting circuit QED systems, shunted with a coherent feedback loop, can change the dynamics of a superconducting transmission line resonator, i.e., a linear quantum cavity, and lead to strong on-chip nonlinear optical phenomena. We find that bistability can occur under the semiclassical approximation, and photon anti-bunching can be shown in the quantum regime. Our study presents new perspectives for engineering nonlinear quantum dynamics on a chip.Comment: 10 pages, 9 figure

Quality of life after curative gastrectomy for gastric cancer in a randomised controlled trial

Quality of life (QOL) was studied in gastric cancer patients treated on a randomised, controlled trial comparing D1 (level 1) with D3 (levels 1, 2 and 3) lymphadenectomy. A total of 221 patients were randomly assigned to D1 (n=110) and D3 (n=111) surgery. Quality-of-life assessments included functional outcomes (a 14-item survey about treatment-specific symptoms) and health perception (Spitzer QOL Index) was performed before and after surgery at disease-free status. Patients suffered from irrelative events such as loss of partners was excluded thereafter. Main analyses were done by intention-to-treat. Thus, 214 D1 (106/110=96.4%) and D3 (108/111=97.3%) R0 patients were assessed. Longitudinal analysis showed that functional outcomes decreased at 6 months after surgery and increased over time thereafter, while health perceptions increased over time in general. On the basis of linear mixed model analyses, patients having total gastrectomy, advanced cancer and hemipancreaticosplenectomy, but not complications had poorer QOL than those without. D1 and D3 patients showed no significant difference in QOL. The results suggest that changes of QOL were largely due to scope of gastric resection, disease status and distal pancreaticosplenectomy, rather than the extent of lymph node dissection. This indicates that nodal dissection can be performed for a potentially curable gastric cancer

Mining Partially-Ordered Sequential Rules Common to Multiple Sequences

© 2015 IEEE. Sequential rule mining is an important data mining problem with multiple applications. An important limitation of algorithms for mining sequential rules common to multiple sequences is that rules are very specific and therefore many similar rules may represent the same situation. This can cause three major problems: (1) similar rules can be rated quite differently, (2) rules may not be found because they are individually considered uninteresting, and (3) rules that are too specific are less likely to be used for making predictions. To address these issues, we explore the idea of mining "partially-ordered sequential rules" (POSR), a more general form of sequential rules such that items in the antecedent and the consequent of each rule are unordered. To mine POSR, we propose the RuleGrowth algorithm, which is efficient and easily extendable. In particular, we present an extension (TRuleGrowth) that accepts a sliding-window constraint to find rules occurring within a maximum amount of time. A performance study with four real-life datasets show that RuleGrowth and TRuleGrowth have excellent performance and scalability compared to baseline algorithms and that the number of rules discovered can be several orders of magnitude smaller when the sliding-window constraint is applied. Furthermore, we also report results from a real application showing that POSR can provide a much higher prediction accuracy than regular sequential rules for sequence prediction

Evolution of superconductivity in K2-xFe4+ySe5: Spectroscopic studies of X-ray absorption and emission.

This study investigates the evolution of superconductivity in K2-xFe4+ySe5 using temperature-dependent X-ray absorption and resonant inelastic X-ray scattering techniques. Magnetization measurements show that polycrystalline superconducting (SC) K1.9Fe4.2Se5 has a critical temperature (T c) of ∼31 K with a varying superconducting volume fraction, which strongly depends on its synthesis temperature. An increase in Fe-structural/vacancy disorder in SC samples with more Fe atoms occupying vacant 4d sites is found to be closely related to the decrease in the spin magnetic moment of Fe. Moreover, the nearest-neighbor Fe-Se bond length in SC samples exceeds that in the non-SC (NS) sample, K2Fe4Se5, which indicates a weaker hybridization between the Fe 3d and Se 4p states in SC samples. These results clearly demonstrate the correlations among the local electronic and atomic structures and the magnetic properties of K2-xFe4+ySe5 superconductors, providing deeper insight into the electron pairing mechanisms of superconductivity

Pentosan polysulfate promotes proliferation and chondrogenic differentiation of adult human bone marrow-derived mesenchymal precursor cells

Extent: 17p.Introduction: This study was undertaken to determine whether the anti-osteoarthritis drug pentosan polysulfate (PPS) influenced mesenchymal precursor cell (MPC) proliferation and differentiation. Methods: Human MPCs were maintained in monolayer, pellet or micromass cultures (MMC) for up to 10 days with PPS at concentrations of 0 to 20 μg/ml. MPC viability and proliferation was assessed using the WST-1 assay and 3H-thymidine incorporation into DNA, while apoptosis was monitored by flow cytometry. Proteoglycan (PG) biosynthesis was determined by 35SO4 2- incorporation and staining with Alcian blue. Proteoglycan and collagen type I and collagen type II deposition in pellet cultures was also examined by Toluidine blue and immunohistochemical staining, respectively. The production of hyaluronan (HA) by MPCs in MMC was assessed by ELISA. The relative outcome of PPS, HA, heparin or dextran sulfate (DS) on PG synthesis was compared in 5-day MMC. Gene expression of MPCs in 7-day and 10-day MMC was examined using real-time PCR. MPC differentiation was investigated by co-culturing with PPS in osteogenic or adipogenic inductive culture media for 28 days. Results: Significant MPC proliferation was evident by day 3 at PPS concentrations of 1 to 5 μg/ml (P < 0.01). In the presence of 1 to 10 μg/ml PPS, a 38% reduction in IL-4/IFNγ-induced MPC apoptosis was observed. In 5-day MMC, 130% stimulation of PG synthesis occurred at 2.5 μg/ml PPS (P < 0.0001), while 5.0 μg/ml PPS achieved maximal stimulation in the 7-day and 10-day cultures (P < 0.05). HA and DS at ≥ 5 μg/ml inhibited PG synthesis (P < 0.05) in 5-day MMC. Collagen type II deposition by MMC was significant at ≥ 0.5 μg/ml PPS (P < 0.001 to 0.05). In MPC-PPS pellet cultures, more PG, collagen type II but less collagen type I was deposited than in controls. Real-time PCR results were consistent with the protein data. At 5 and 10 μg/ml PPS, MPC osteogenic differentiation was suppressed (P < 0.01). Conclusions: This is the first study to demonstrate that PPS promotes MPC proliferation and chondrogenesis, offering new strategies for cartilage regeneration and repair in osteoarthritic joints.Peter Ghosh, Jiehua Wu, Susan Shimmon, Andrew CW Zannettino, Stan Gronthos and Silviu Itesc

Comments on theoretical foundation of “EM Drive”

The concept of EM Drive has attracted much attention and groups of work have been conducted to prove or verify it, of which the published experimental outcome is criticized in great details while the theoretical foundation has not been discussed. The present essay investigates on the theoretical derivations of the net thrust in the &ldquo;EM drive&rdquo; and reveals the self-contradiction arising at the very start, when the law of conservation of momentum was utilized and opposed simultaneously.The concept of EM Drive has attracted much attention and groups of work have been conducted to prove or verify it, of which the published experimental outcome is criticized in great details while the theoretical foundation has not been discussed. The present essay investigates on the theoretical derivations of the net thrust in the &ldquo;EM drive&rdquo; and reveals the self-contradiction arising at the very start, when the law of conservation of momentum was utilized and opposed simultaneously.</p

Simultaneously characterizing the comparative economics of routine female adolescent nonavalent human papillomavirus (HPV) vaccination and assortativity of sexual mixing in Hong Kong Chinese: a modeling analysis.

BACKGROUND: Although routine vaccination of females before sexual debut against human papillomavirus (HPV) has been found to be cost-effective around the world, its cost-benefit has rarely been examined. We evaluate both the cost-effectiveness and cost-benefit of routine female adolescent nonavalent HPV vaccination in Hong Kong to guide its policy, and by extension that of mainland China, on HPV vaccination. One major obstacle is the lack of data on assortativity of sexual mixing. Such difficulty could be overcome by inferring sexual mixing parameters from HPV epidemiologic data. METHODS: We use an age-structured transmission model coupled with stochastic individual-based simulations to estimate the health and economic impact of routine nonavalent HPV vaccination for girls at age 12 on cervical cancer burden and consider vaccine uptake at 25%, 50%, and 75% with at least 20 years of vaccine protection. Bayesian inference was employed to parameterize the model using local data on HPV prevalence and cervical cancer incidence. We use the human capital approach in the cost-benefit analysis (CBA) and GDP per capita as the indicative willingness-to-pay threshold in the cost-effectiveness analysis (CEA). Finally, we estimate the threshold vaccine cost (TVC), which is the maximum cost for fully vaccinating one girl at which routine female adolescent nonavalent HPV vaccination is cost-beneficial or cost-effective. RESULTS: As vaccine uptake increased, TVC decreased (i.e., economically more stringent) in the CBA but increased in the CEA. When vaccine uptake was 75% and the vaccine provided only 20 years of protection, the TVC was US$444 ($373-506) and $689 ($646-734) in the CBA and CEA, respectively, increasing by approximately 2-4% if vaccine protection was assumed lifelong. TVC is likely to be far higher when non-cervical diseases are included. The inferred sexual mixing parameters suggest that sexual mixing in Hong Kong is highly assortative by both age and sexual activity level. CONCLUSIONS: Routine HPV vaccination of 12-year-old females is highly likely to be cost-beneficial and cost-effective in Hong Kong. Inference of sexual mixing parameters from epidemiologic data of prevalent sexually transmitted diseases (i.e., HPV, chlamydia, etc.) is a potentially fruitful but largely untapped methodology for understanding sexual behaviors in the population

Full-commanding a network: The dictator

A network of chaotic dynamical systems may synchronize. For some networks there is the possibility that, coupling a new node to the network, the synchronization will be commanded by that new node. That possibility depends on the network and on the way the new node is coupled to the network.We consider a coupling that can provide what we call a full-commanding and we define the corresponding full-commandwindow. The limit situations corresponding to a completely connected network and to a completely disconnected one provide us some understanding about what makes a network more receptive or more resistant to commanding