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Numerical simulation of dam-break water flow over a horizontal dry bed has been performed. We have modified and verified computational techniques, including methods for determining the position of the interface and the continuum model for the surface tension force implemented in the PIFI code, as well as the OpenFOAM software with the interFoam solver and various cases of the two-parameter () model with corrections made taking into account the behavior of flows in regions of low Reynolds numbers. Calculated integral characteristics of dam-break flow were analyzed and compared with measured data. It is shown that taking into account surface tension and using an adequate turbulence model leads to deceleration of water flow and hence to a decrease in the velocity of the wave front, resulting in better agreement between the results of calculations and laboratory experiments. [ABSTRACT FROM AUTHOR]

High-resolution elemental profiles were obtained from SiO2(N) /4H-SiC structures by spatially resolved electron energy-loss spectroscopy (EELS) performed in the scanning transmission electron microscopy mode. The results show that following annealing in NO, N was exclusively incorporated within ~1 nm of the SiO2(N) /4H-SiC interface. Mean interfacial nitrogen areal densities measured by EELS were ~(1.0±0.2)×1015 cm-2 in carbon-face samples and (0.35±0.13)×1015 cm-2 in Si-face samples; these results are consistent with nuclear reaction analysis measurements. Some of the interface regions in the C-face samples also showed excess carbon that was not removed by the NO annealing process, in contrast with previous results on Si-face samples. [ABSTRACT FROM AUTHOR]

Nitrogen incorporation at the SiO2/SiC interface due to annealing in NO is measured and shown to be a strong function of crystal face. The annealing process involves two major solid-state chemical reactions: nitrogen uptake at the interface and N loss associated with second-order oxidation. An ad hoc kinetics model explains the experimental observations of anisotropy and nitrogen saturation. [ABSTRACT FROM AUTHOR]

In this study we investigated the morphology and interfacial chemistry of (0001) 4H-SiC-based metal-oxide-semiconductor field-effect transistors (MOSFETs) as a function of post-oxidation annealing in nitric oxide (NO) following wet oxidation. Energy-filtered transmission electron microscopy analyses showed enhanced C/Si concentrations (up to 13%) at distinct locations along the SiO2/SiC interface in the MOSFETs that were not annealed in NO. In contrast, regions of enhanced C/Si concentration were not detected in the MOSFETs that were annealed in NO; instead, these samples showed a trace amount of interfacial N. The introduction of N may therefore be associated with a reduction of C in these samples and may contribute to the higher channel mobility (∼38 cm2/V s) in the samples annealed in NO relative to the samples that were not annealed in NO (∼9 cm2/V s). Rough SiO2/4H-SiC interfaces and nonuniform oxide thickness were observed on both the NO- and the non-NO-annealed samples. The rough interfaces shown in the transmission electron microscopy bright field images may also be an important factor limiting the channel mobility in SiC-based MOSFETs. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Background: The study aimed to investigate the physiology, psychophysics, pathology and their relationship in reversible nociceptive nerve degeneration, and the physiology of acute hyperalgesia.Methods: We enrolled 15 normal subjects to investigate intraepidermal nerve fibre (IENF) density, contact heat-evoked potential (CHEP) and thermal thresholds during the capsaicin-induced skin nerve degeneration-regeneration; and CHEP and thermal thresholds at capsaicin-induced acute hyperalgesia.Results: After 2-week capsaicin treatment, IENF density of skin was markedly reduced with reduced amplitude and prolonged latency of CHEP, and increased warm and heat pain thresholds. The time courses of skin nerve regeneration and reversal of physiology and psychophysics were different: IENF density was still lower at 10 weeks after capsaicin treatment than that at baseline, whereas CHEP amplitude and warm threshold became normalized within 3 weeks after capsaicin treatment. Although CHEP amplitude and IENF density were best correlated in a multiple linear regression model, a one-phase exponential association model showed better fit than a simple linear one, that is in the regeneration phase, the slope of the regression line between CHEP amplitude and IENF density was steeper in the subgroup with lower IENF densities than in the one with higher IENF densities. During capsaicin-induced hyperalgesia, recordable rate of CHEP to 43 °C heat stimulation was higher with enhanced CHEP amplitude and pain perception compared to baseline.Conclusions: There were differential restoration of IENF density, CHEP and thermal thresholds, and changed CHEP-IENF relationships during skin reinnervation. CHEP can be a physiological signature of acute hyperalgesia.Significance: These observations suggested the relationship between nociceptive nerve terminals and brain responses to thermal stimuli changed during different degree of skin denervation, and CHEP to low-intensity heat stimulus can reflect the physiology of hyperalgesia. [ABSTRACT FROM AUTHOR]

Recent advance of periodic materials from the field of solid-state physics into that of earthquake engineering has resulted in a novel seismic isolation technique. In this study, we developed a new configuration of structural foundation using a three-dimensional (3D) periodic material for seismic isolation of critical infrastructure, particularly nuclear infrastructure. To this aim, we first performed analytical and finite element studies to compare two different types of 3D unit cells, i.e., Bragg Scattering and Locally resonant unit cells, to investigate their characteristics and applicability as a seismic isolator. We then designed a large scale test specimen based on the Bragg-scattering type unit cell using common construction materials: reinforced concrete blocks and polyurethane sheets. The designed test specimen was constructed and tested using a shake table subjected to different types of excitations in the horizontal and vertical directions as well as the torsional mode. The dynamic response of a small modular reactor (SMR) building model protected by the 3D periodic foundation demonstrates that 90% response reduction was achieved within the frequency band gaps. The response attenuation was achieved in all three tested directions. Moreover, the periodic foundation-isolated SMR building exhibited a stable response with negligible rocking on the structural system. [ABSTRACT FROM AUTHOR]

The article describes the case of a 51-year-old man with a history of end-stage renal disease secondary to hypertension who received a living donor renal transplant in 1996. Topics include treatment received by the patient, finding on histopathology of biopsy specimen, and symptoms of tuberculous (TB) enteritis.

Abstract: To assist managers in monitoring the progress of their IT programs, we propose a Bayesian Network stochastic model, the IT Decision Management System (ITDMS), to simulate the program's evidence observations, complex interrelationships, and the dynamic/temporal relationships. Based on the Information Technology Infrastructure Library (ITIL)®1 The model aligns the sub‐process of each ITIL Phase in a Bayesian structure measuring status to provide the decision maker a measurement of the likelihood of program success. [ABSTRACT FROM AUTHOR]

Dynamic asset allocation in financial investment with an optimal equity growth principle based on mutual information in communication theory is considered. Specifically, the asset allocation formula using Kelly's criteria derived from channel capacity of a binary symmetric channel is developed. The goal is to determine the optimal fraction of equity to be invested between a risk-free asset and a risky asset in a repeated trading activity. The analytical operating curve to predict trading performance is provided. An extension for dynamic multi-asset allocation is also presented. An out-of-sample simulation based on historical market data demonstrates the effectiveness of the methodology. [ABSTRACT FROM AUTHOR]

Adaptation of metamaterials at micro- to nanometer scales to metastructures at much larger scales offers a new alternative for seismic isolation systems. These new isolation systems, known as periodic foundations, function both as a structural foundation to support gravitational weight of the superstructure and also as a seismic isolator to isolate the superstructure from incoming seismic waves. Here we describe the application of periodic foundations for the seismic protection of nuclear power plants, in particular small modular reactors (SMR). For this purpose, a large-scale shake table test on a one-dimensional (1D) periodic foundation supporting an SMR building model was conducted. The 1D periodic foundation was designed and fabricated using reinforced concrete and synthetic rubber (polyurethane) materials. The 1D periodic foundation structural system was tested under various input waves, which include white noise, stepped sine and seismic waves in the horizontal and vertical directions as well as in the torsional mode. The shake table test results show that the 1D periodic foundation can reduce the acceleration response (transmissibility) of the SMR building up to 90%. In addition, the periodic foundation-isolated structure also exhibited smaller displacement than the non-isolated SMR building. This study indicates that the challenge faced in developing metastructures can be overcome and the periodic foundations can be applied to isolating vibration response of engineering structures. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the characteristics of gynecologic cancer patients visiting the emergency department (ED). Materials and Methods: A retrospective cohort of gynecologic cancer patients in ED visits from 2000 to 2012 was analyzed using the Longitudinal Health Insurance Database 2000 (LHID2000) which randomly selected 1,000,000 beneficiaries from the year 2000 Registry of Beneficiaries (n = 23.72 million). Results: There were 5,893 ED visits by 1,400 gynecologic cancer patients. The mean age was 55.22 ± 14.60 years. The mean number of ED visits was 4.21±5.18. 657 (46.93%) patients that were admitted to hospital; 70.57% ED visits occurred in medical center. Abdominal pain (19.04%), complications of surgical and medical care (13.28%) and intestinal obstruction without mention of hernia (10.69%) are the most three common presenting symptoms except other symptoms, signs, and ill-defined conditions (24.79%); 62.56% of the medications prescribed in ED visits are of gastrointestinal category. The overall survival rate of ED visits was significantly lower than that of no ED visits (p < 0.0001). Conclusions: Relatively low rate of hospital admission may indicate unnecessary ED visits resulting in healthcare costs. Abdominal pain is the most common specific symptoms at presentation. Most medications belong to the gastrointestinal category reminding us of the importance of nutrition support. ED visits were a significant poor prognostic factor for overall survival. [ABSTRACT FROM AUTHOR]

Value-at-Risk (VaR) is a well-accepted risk metric in modern quantitative risk management (QRM). The classical Monte Carlo simulation (MCS) approach, denoted henceforth as the classical approach, assumes the independence of loss severity and loss frequency. In practice, this assumption does not always hold true. Through mathematical analyses, we show that the classical approach is prone to significant biases when the independence assumption is violated. This is also corroborated by studying both simulated and real-world datasets. To overcome the limitations and to more accurately estimate VaR, we develop and implement the following two approaches for VaR estimation: the data-driven partitioning of frequency and severity (DPFS) using clustering analysis, and copula-based parametric modeling of frequency and severity (CPFS). These two approaches are verified using simulation experiments on synthetic data and validated on five publicly available datasets from diverse domains; namely, the financial indices data of Standard & Poor's 500 and the Dow Jones industrial average, chemical loss spills as tracked by the US Coast Guard, Australian automobile accidents, and US hurricane losses. The classical approach estimates VaR inaccurately for 80% of the simulated data sets and for 60% of the real-world data sets studied in this work. Both the DPFS and the CPFS methodologies attain VaR estimates within 99% bootstrap confidence interval bounds for both simulated and real-world data. We provide a process flowchart for risk practitioners describing the steps for using the DPFS versus the CPFS methodology for VaR estimation in real-world loss datasets. [ABSTRACT FROM AUTHOR]

This paper describes a continuous-time state-process, discretetime observation, Interacting Multiple Model (IMM) tracking algorithm, and its applications to financial market modeling and asset allocation. The system state is modeled as a continuous-time, affine-Gaussian stochastic dynamical process driven by a white process noise, as well as by structural changes modeled by a finitestate, continuous-time, Markov process. The system generally assumes multiple models with different state space dimensions and an affine-Gaussian state jump whenever a model transition occurs. The underlying problem is a standard filtering problem for estimating the system state based on a sequence of discrete-time, linear- Gaussian observations of partial system states. To demonstrate the new method, we apply the IMM algorithm to financial market modeling for dynamic asset allocation. The resulting performance shows the potential applicability of the proposed method. [ABSTRACT FROM AUTHOR]

Background and purpose: Fabry disease is an X‐linked disease, and enzyme‐based screening methods are not suitable for female patients. Methods: In total, 1000 young stroke patients (18–55 years, 661 with ischaemic stroke and 339 with hypertensive intracerebral hemorrhage) were recruited. The Sequenom iPLEX assay was used to detect 26 Fabry related mutation genes. The frequency of Fabry disease in young stroke was reviewed and compared between Asian and non‐Asian countries. Results: Two male patients with ischaemic stroke were found to have a genetic mutation of IVS4+919G>A. There was no α‐galactosidase A (GLA) gene mutation in female patients. The frequency in Asian stroke patients was 0.62% (male vs. female 0.63% vs. 0.58%) with 0.72% for ischaemic stroke and none for hemorrhagic stroke, compared to 0.88% (0.77% vs. 1.08%) with 0.83% for ischaemic stroke and 1.40% for hemorrhagic stroke reported in western countries. Conclusion: IVS4+919G>A is the GLA mutation in Taiwanese young ischaemic stroke patients. Fabry disease is more frequent among non‐Asian patients compared to Asian patients. [ABSTRACT FROM AUTHOR]

We develop a nonlinear spectral graph theory, in which the Laplace operator is replaced by the 1 − Laplacian Δ1. The eigenvalue problem is to solve a nonlinear system involving a set valued function. In the study, we investigate the structure of the solutions, the minimax characterization of eigenvalues, the multiplicity theorem, etc. The eigenvalues as well as the eigenvectors are computed for several elementary graphs. The graphic feature of eigenvalues are also studied. In particular, Cheeger's constant, which has only some upper and lower bounds in linear spectral theory, equals to the first nonzero Δ1 eigenvalue for connected graphs. [ABSTRACT FROM AUTHOR]

Acinetobacter baumannii represents a significant cause of nosocomial infections. Therefore, we combined real-time quantitative polymerase chain reaction (PCR) with the propidium monoazide ( PMA-q PCR) to assess the feasibility of detecting viable, airborne A. baumannii. The biological collection efficiencies of three samplers for collecting airborne A. baumannii were evaluated by PMA-q PCR in a chamber study. After sampling, the effects of storage in collection fluid on A. baumannii were evaluated. The results showed that the culturable ratio of A. baumannii measured using the culture method was significantly correlated with the viable ratio measured using PMA-q PCR, but was not significantly correlated with the q PCR results. It was indicated that the AGI-30 impinger and the Bio Sampler were much more effective than the Nuclepore filter sampler for collecting airborne A. baumannii. The storage temperature was critical for aerosol samples, as the loss of viable A. baumannii was minimized when the PMA-bound DNA was stored at −20°C or if the collected cells were stored at 4°C and subsequently processed by PMA-q PCR within 1 month. The PMA-q PCR method was also to distinguish between colistin-sensitive and colistin-resistant A. baumannii, and no colistin-sensitive A. baumannii was detected by PMA-q PCR upon treatment of the Bio Sampler collection medium with 2 μg/ml colistin for 5 min. [ABSTRACT FROM AUTHOR]

The automated high-throughput Abbott RealTi me MTB real-time PCR assay has been recently launched for Mycobacterium tuberculosis complex (MTBC) clinical diagnosis. This study would like to evaluate its performance. We first compared its diagnostic performance with the Roche Cobas TaqMan MTB assay on 214 clinical respiratory specimens. Prospective analysis of a total 520 specimens was then performed to further evaluate the Abbott assay. The Abbott assay showed a lower limit of detection at 22.5 AFB/ml, which was more sensitive than the Cobas assay (167.5 AFB/ml). The two assays demonstrated a significant difference in diagnostic performance (McNemar's test; P = 0.0034), in which the Abbott assay presented significantly higher area under curve (AUC) than the Cobas assay (1.000 vs 0.880; P = 0.0002). The Abbott assay demonstrated extremely low PCR inhibition on clinical respiratory specimens. The automated Abbott assay required only very short manual handling time (0.5 h), which could help to improve the laboratory management. In the prospective analysis, the overall estimates for sensitivity and specificity of the Abbott assay were both 100 % among smear-positive specimens, whereas the smear-negative specimens were 96.7 and 96.1 %, respectively. No cross-reactivity with non-tuberculosis mycobacterial species was observed. The superiority in sensitivity of the Abbott assay for detecting MTBC in smear-negative specimens could further minimize the risk in MTBC false-negative detection. The new Abbott RealTi me MTB assay has good diagnostic performance which can be a useful diagnostic tool for rapid MTBC detection in clinical laboratories. [ABSTRACT FROM AUTHOR]

Large information technology (IT) projects such as Defense Business System (DBS) acquisitions have been experiencing an alarming rate of large cost overruns, long schedule delays, and under-delivery of specified capabilities. There are s tric t defense acquisition laws/regulations/policies/guidance with an abundance of review and oversights, generating a plethora of data and evidence for project progress. However, with the size and complexity of these large IT projects and sheer amount of project data they produce, there are challenges in collectively discerning these data and making successful decisions based on them. This research article develops an analytic model with Bayesian networks to orient the vast number of acquisition data and evidence to support decision making, known as the DBS Acquisition Probability of Success (DAPS) model. [ABSTRACT FROM AUTHOR]

A UV-curing technique was used to develop advanced anticorrosive coatings made of a poly(methyl methacrylate) (PMMA)/silica composite (PSC) with bioinspired Xanthosoma sagittifolium leaf-like superhydrophobic surfaces. First of all, a transparent soft template with negative patterns of xanthosoma sagittifolium leaf can be fabricated by thermally curing the polydimethylsiloxane (PDMS) pre-polymer in molds at 60°C for 4 h, followed by detaching PDMS template from the surface of natural leaf. PSC coatings with biomimetic structures can be prepared by performing the UV-radiation process upon casting UV-curable precursor with photo-initiator onto cold-rolled steel (CRS) electrode under PDMS template. Subsequently, UV-radiation process was carried out by using light source with light intensity of 100 mW/cm2 with exposing wavelength of 365 nm. Surface morphologies of the as-synthesized hydrophobic PMMA (HP) and superhydrophobic PSC (SPSC) coatings showed a large number of micro-scaled mastoids, each decorated with many nano-scaled wrinkles that were systematically investigated by using scanning electron microscopy (SEM). The contact angles of water droplets on the sample surfaces can be increased from ~81 and 103° on PMMA and PSC surfaces to ~148 and 163° on HP and SPSC surfaces, respectively. The SPSC coating was found to provide an advanced corrosion protection effect on CRS electrodes compared to that of neat PMMA, PSC, and HP coatings based on a series of electrochemical corrosion measurements in 3.5 wt% NaCl electrolyte. Enhanced corrosion protection of SPSC coatings on CRS electrodes can be illustrated by that the silica nanoparticles on the small papillary hills of the bioinspired structure of the surface further increased the surface roughness, making the surface exhibit superior superhydrophobic, and thus leading to much better anticorrosion performance. [ABSTRACT FROM AUTHOR]