cssi/SciSciGPT-SciSciNet huggingface dataset:
Snodgrass Tubularized Incised Plate Urethroplasty for Distal and Midpenile Hypospadias

Introduction : Despite hundreds of repair techniques for hypospadias, the introduction of tubularized incised plate urethroplasty (TIP) by Warren T. Snodgrass has become popular because of good functional and cosmetic outcome. The objective of this study was to share our experience of Snodgrass tubularized incised plate (TIP) urethroplasty for the repair of distal and mid-penile hypospadias. Materials and Methods : This prospective study was carried out for a period of 24 months. It included 46 male patients with the mean age of 4.1 years (18 months to 10 years). Proximal hypospadias and those distal with moderate to severe chordee were excluded. All cases underwent TIP urethroplasty as described by Snodgrass and the neourethra was covered by single or double layer of dorsal prepucial layer. The results were analyzed on the basis of duration of surgery, types of postoperative complications like urethrocutaneous fistula, meatal stenosis and wound dehiscence. Functional results assessed with ease of voiding, force and direction of urinary stream and cosmetic with external look of penis. Results: The overall complication rate requiring surgical intervention was 8 (17.3%). Mean duration of surgery was 66 minutes (60-80 minutes). Urethrocutaneous fistula occurred in 5 (10.8%), meatal stenosis in 1 (2.1%) and wound dehiscence in 2 (4.3%) patient. The cosmetic appearance was excellent in all patients involved in this study except 2 cases of wound dehiscence. All of them had vertically oriented slit like meatus with straight urinary stream. Conclusion: Tubularized incised plate urethroplasty gives good functional and excellent cosmetic results with low rate of complications in distal and mid-penile hypospadias. DOI: http://dx.doi.org/10.3126/jnps.v34i1.8692 J Nepal Paediatr Soc 2014;34(1):29-33
Model for predicting the performance of membrane bioadsorber reactor process in water treatment applications

Abstract This research focuses on the development of a mathematical model for performance prediction/simulation of the membrane bioadsorber reactor (MBR) process. The MBR process integrates biodegradation, adsorption and membrane filtration, for water or wastewater treatment and water reclamation. The model sub-processes include the following phenomenological aspects: (a) biological reaction in bulk liquid solution, (b) film transfer from bulk liquid phase to the biofilm, (c) diffusion with biological reaction inside biofilm, (d) adsorption equilibrium at the biofilm–adsorbent interface, and (e) diffusion within the adsorbent (powder activated carbon) particles. The model exhibited good simulative capability for three model organic compounds, namely, phenol, para-nitrophenol, and toluene, chosen based on their varying adsorption and biodegradation characteristics. A phenomenological approach was employed to examine the relative contributions of adsorption and biodegradation to contaminant removal, and to obtain insights into adsorbent bioregeneration. Therefore, simulation studies were conducted under three different scenarios: (a) adsorption and biodegradation in biofilm and liquid phase suspension are operative, conforming to the assumptions of the generalized model; (b) biodegradation is operative in biofilm as well as liquid phase suspension, but adsorption is absent; and (c) adsorption alone is operative without biodegradation. Sensitivity studies were preformed to investigate the dependence of process dynamics on model parameters pertaining to adsorption equilibrium and kinetics, liquid film transport, biofilm diffusion, biochemical reaction kinetics, influent concentration, and reactor flow conditions.
Intelligent Scraping Experience Using Ultrasonics in Two 60/56 Dual Diameter 100 km. Seawater Transmission Pipelines in Saudi Arabia

Saudi ARAMCO`s two 60in./56in. (1524/1422 mm) diameter Seawater Injection Pipelines used for secondary oil recovery stretch from the Seawater Treatment Plant across the Arabian Desert for a distance of approximately 100 kilometers. Both lines were put into operation in mid 1978 using over the ditch Plicoflex tape wrap as a means of protection against external corrosion. A significant portion of both pipelines (32 km of each line) runs through Subkha (salty moist) areas. A series of test hole evaluations in 1989 indicated moderate to sever external corrosion particularly in Subkha which necessitated sleeving and external coating application. In 1991 a series of leaks, four (4) in total over a period of two (2) months occurred in Pipeline {number_sign}2 due to external corrosion. This suggested that the line(s) were in urgent need of at least partial replacement or major rehabilitation. Prior to making a final decision on partial replacement it was decided to run an Intelligent Scraper in both pipelines to ascertain both internal and external pipeline conditions. An Ultrasonic Scraper the largest of it`s kind in the world, similar to what was used in the Alyeska Pipeline was developed and successfully run in both pipelines in February 1993. This papermore » discusses the pipeline history, test hole evaluations, Intelligent Scraping experiences, field evaluation for anomaly verification, and repair of approximately 120 locations as identified by the Intelligent Scraping run. The Intelligent Scraping evaluation played a major role in the cancellation of partial pipeline replacement with cost savings estimated $30 MM.« less
Reducing the cell to module efficiency gap in thin film PV using in-line post-process scribing isolation

The persistent gap between cell and module efficiencies, the so called solar gap, is an important problem for all PV technologies. In thin film PV (TFPV), a significant portion of this efficiency loss can be traced to parasitic shunts distributed throughout the module. In this work, we describe an in-line, post deposition scribing technique for electrically isolating these distributed shunts in a monolithic thin film PV module. The localized scribes minimize the losses due to defective shunts by restricting lateral current drain from its (otherwise defect-free) neighbors, and promise to reduce the solar gap by 30-50%. This technique can be easily integrated with state of the art inline manufacturing and metrology methods, and is applicable for all thin film PV technologies.
Exposure to female pheromones stimulates a specific type of neuronal population in the male but not female magnocellular division of the medial preoptic nucleus (MPN mag) of the Syrian hamster

The magnocellular division of the medial preoptic area (MPN mag) integrates pheromonal and hormonal signals to play a critical role in the expression of male typical sex behavior. The MPN mag contains two morphologically distinct neuronal populations; the percentage of each type within the nucleus is sex specific. Males have more neurons with a single nucleolus whereas females have more with multiple nucleoli. To determine which neuronal subtype mediates pheromonal induction of copulation, tissue from male and female hamsters exposed to female pheromones was immunolabeled for the immediate early protein (EGR-1). Subsequently the tissue was counterstained and the number of ERG-1 neurons with one or two nuclei was determined. The results indicate that pheromones stimulate neurons with single nucleoli in males but fail to stimulate either neuronal subtype in females suggesting that synaptic input to the MPN mag is sexually differentiated.
Relations between the structures of phases in the system platinum-molybdenum

Abstract A study has been made of crystal structure changes effected by heat treatment of platinum-coated molybdenum wire. At temperatures above about 800°C, solid diffusion of molybdenum into the platinum occurs. This causes alterations in the atomic arrangement, and as the Mo-content increases, four intermediate alloy phases develop in succession. These are denoted by the symbols β, γ, δ and e. β Pt3Mo has a face-centred tetragonal structure, γ Pt2Mo is orthorhombic pseudo-hexagonal, the δ phase ranging in composition from Pt3Mo2 to at least PtMo2 has an ordered A3 type hexagonal structure, whilst e PtMo3 has the cubic A15 type structure. Through the sequence of structure transitions, the pivotal feature appears to be the persistence of the more or less close-packed layers of atoms. The spacing of these planes in the various structures alters only slightly throughout the series, although the composition changes are considerable. The relationship between the five structures, including that of pure platinum, appears to be very close, so that transitions occur with the minimum of atomic movement and alteration of lattice spacings. The phases are thus almost akin to a sequence of discrete but ordered solid solutions. Structure data and planar spacing lists for the four intermediate phases, compiled from their X-ray patterns, are given.
Applying the transtheoretical model to cervical cancer screening in Vietnamese‐American women

Background: Low levels of Papanicolaou (Pap) screening participation in Vietnamese-American women remain a significant public health problem. The transtheoretical model (TTM) suggests that individuals adopting Pap smear behaviour move through a series of stages of readiness to change. Determining a woman's level of readiness for regular Pap testing and identifying the screening behaviour that an individual already performs is important in the development of successful intervention programmes that address the specific needs of Vietnamese-American women in different stages. Aims: To describe Pap smear screening behaviours of Vietnamese-American women, and to examine whether constructs (stages of change, self-efficacy and perceived benefits/barriers) from the TTM are applicable to Vietnamese-American women relative to Pap testing. Methods: A descriptive, cross-sectional design with snowball sampling was used to recruit participants. A total of 80 Vietnamese-American women completed the self-administered questionnaire. Results: Most respondents (62.5%) reported previous Pap testing and only 46.3% receiving regular Pap testing. Compared with those in the pre-contemplation stage of the TTM, participants in maintenance reported significantly less self-efficacy (F (3, 73) = 4.85, P = 0.00), a lower level of perceived barriers (F (3, 75) = 5.99, P = 0.00) and a higher level of perceived benefits (F (3, 76) = 3.91, P = 0.01) relative to Pap smear. Conclusions: The results support some of the assumptions of the TTM but raise questions about the predicted relationships between stages of change and self-efficacy. Continued research is needed to identify the most effective theory-based interventions for evidence-based nursing practice in this population.
Determinism as a Thesis about the State of the World from Moment to Moment

Determinism, as the thesis that given the state of the world at a moment there is only one way it can be at the next moment, is problematic. After explaining why the thesis is defined as it is, the paper goes on to raise questions about the terms in which it is defined. Is the 'world' to be understood as constituted by whatever figures in our talk or thought, or to what is reconstituted by an ontology seemingly derived from the sciences? Either way of understanding it is shown to be inadequate. Despite the fact that it is not clear why there is a need for a position at all, determinists think of determinism as the default position. Honderich says that it is 'remarkable' that apart from the concern with 'whether choices and actions are free ... what we find is determinism and hardly anything else.'1 What he means is that we do not find much support for indeterminism (or a third alternative). However, it is unclear what we are looking for when we find hardly anything but determinism. Why are so many philosophers determinists, when determinism, as a metaphysical thesis, seems hard to understand, let alone defend? After explaining what is problematic about determinism, I conclude with some remarks about its real appeal. 1. Determinism as a Metaphysical Thesis William James uses the metaphor of pregnancy to express the basic idea: 1 T. Honderich, 'Determinism as True, Both Compatibilism and Incompatibilism as False, and the Real Problem', The Oxford Handbook of Freewill, R. Kane (ed.) (New York: Oxford University Press), 461. 10.1017/S0031819107000022 ?2007 The Royal Institute of Philosophy Philosophy 82 2007 399 This content downloaded from 157.55.39.4 on Thu, 08 Sep 2016 05:17:57 UTC All use subject to http://about.jstor.org/terms
Analysis of host plant resistance to multiple Fusarium species associated with stalk rot disease in sorghum [Sorghum bicolor (L.) Moench]

Abstract Fusarium spp. is among the largest and most important pathogen groups that attack major grain crops including sorghum. The objectives of this study were to compare the virulence of Fusarium spp. associated with sorghum and examine the mode of resistance of genotypes to the disease. Eight Fusarium species – F. verticillioides, F. thapsinum, F. andiyazi, F. proliferatum, F. nyagamai, F. pseudoanthophilum, F. brevicatenulatum, and F. pseudonygamai – were studied using three sorghum genotypes under greenhouse condition. Three of these pathogens (F. verticillioides, F. thapsinum, and F. andiyazi) were selected for genetic analysis of resistance under field conditions. Sorghum genotypes with contrasting stalk rot reactions were selected for use in both the greenhouse and field experiments. Two weeks after flowering, plants were inoculated with liquid inoculum culture (5 × 104 conidia ml−1) of the different pathogens. Plants were harvested 4 weeks after inoculation and rated for disease severity on the basis of lesion length and number of nodes crossed by the lesion. Among the pathogens, F. thapsinum resulted in consistently higher disease scores in all genotypes under all environments. Likewise, genotype SC599 showed the greatest and most stable resistance as inbred as well as in hybrid combinations as shown by consistently high GCA for resistance to all pathogen species. We recommend that future screening exercises for Fusarium stalk rot resistance utilize F. thapsinum as the causal organism and include the resistant genotype SC599 as a control.
Double-diffusive interleaving on horizontal gradients

Results are presented from laboratory experiments on lateral intrusive flows driven by horizontal gradients of properties in double-diffusive systems. These are variations on the classical experiments in which salt stratified fluid was separated from a sugar stratified fluid by a removable barrier. With the removal of this barrier, lateral intrusions of sugar solution into the salt solution alternated in the vertical with salt intrusions into the sugar solution. In our present study, the fluid has continuous horizontal gradients of sugar, density-compensated by opposing horizontal gradients of salt, rather than the discontinuity of properties in the classical experiments. Observations of these new experiments include: shadowgraphs, PTV (particle tracking velocimetry) showing the structure of the flow, and PIV (particle-image velocimetry) from which velocity vector fields on a vertical plane were obtained; from these, mean flows, Reynolds stresses, and associated momentum fluxes were computed. These experiments have been conducted for three regimes of vertical stratification: (i) Salt-finger favourable (‘hot and salty’ above); (ii) Diffusive convection favourable (‘hot and salty’ below); (iii) Doubly stable (‘cold and salty’ below). One of our main conclusions concerns the driving mechanism for the horizontal intrusive flow. Away from the front or ‘nose’ of the intrusions, the lateral flows are no longer tilted but are horizontal. Here, finger layers alternate in the vertical with convecting layers. In these convecting layers, vertical transport of horizontal momentum by the Reynolds stress plays a major role in maintaining the lateral motion against viscous dissipation.
Thioredoxin reductase from Escherichia coli: Evidence of restriction to a single conformation upon formation of a crosslink between engineered cysteines

Thioredoxin reductase is a flavoprotein which catalyzes the reduction of the small protein thioredoxin by NADPH. It contains a redox active disulfide and an FAD in each subunit of its dimeric structure. Each subunit is further divided into two domains, the FAD and the pyridine nucleotide binding domains. The orientation of the two domains determined from the crystal structure and the flow of electrons determined from mechanistic studies suggest that thioredoxin reductase requires a large conformational change to carry out catalysis (Williams CH Jr, 1995, FASEB J 9:1267-1276). The constituent amino acids of an ion pair, E48/R130, between the FAD and pyridine nucleotide binding domains, were mutagenized to cysteines to form E48C, R130C (CC mutant). Formation of a stable bridge between these cysteines was expected to restrict the enzyme largely in the conformation observed in the crystal structure. Crosslinking with the bifunctional reagent N, N,1,2 phenylenedimaleimide, spanning 4-9 A, resulted in a <95 % decrease in thioredoxin reductase and transhydrogenase activity. SDS-PAGE confirmed that the crosslink in the CC-mutant was intramolecular. Dithionite titration showed an uptake of electrons as in wild-type enzyme, but anaerobic reduction of the flavin with NADPH was found to be impaired. This indicates that the crosslinked enzyme is in the conformation where the flavin and the active site disulfide are in close proximity but the flavin and pyridinium rings are too far apart for effective electron transfer. The evidence is consistent with the hypothesis that thioredoxin reductase requires a conformational change to complete catalysis.
Development of the middle latency response in an animal model and its relation to the human response

Although the clinical use of the middle latency response (MLR) in adults is fairly straightforward, its use is complicated by maturational changes that continue throughout the first decade of life. In order to telescope the time period of this long developmental course, we have approached the study of MLR maturation using the gerbil as an animal model. The course of MLR obtained over the temporal lobe development was characterized in the Monogolian gerbil ranging in age from 10 days to 3 months of life. The adult gerbil MLR consists of two positive peaks (A and C) at 11 and 25 ms, respectively, and a negative component (B) at 16 ms. These components emerge in a systematic fashion as a function of age. The present work supports a strong age effect of increased MLR detectability in the gerbil, similar to findings reported for humans. Wave A was infrequently detected in young animals, but when present, it occurred at adult latencies. The latency of waves B and C decreased systematically with age. The amplitude of all components increased with age, similar to findings in humans. The fact that adult-like thresholds were obtained shortly after birth indicates that when present, MLRs may be a good index of hearing threshold. Effects of stimulating across a wide range of intensities were described. The gerbil model appears appropriate for the study of development of the central auditory system function.
A Meteorological Telemetry System for Gun-Launched Probes

A telemetry system has been developed for meteorological investigations of the upper atmosphere that is capable of withstanding gun-launched environments of 60 000 g. This system was developed for the Project HARP (High Altitude Research Probe) 5-inch gun. The telemeter is part of a parachute payload that is ejected at altitudes up to 70 km and records temperature during descent. The telemeter consists of a VHF transmitter, with a power output of 300 milliwatts, modulated by a standard IRIG subcarrier oscillator. An in-flight calibrator is used to obtain a 2-point resistance calibration at the input of the SCO. The system is powered by nickel cadmium batteries and is capable of transmission for periods from 30 to 60 minutes.
Statistical models for exposure-biomarker relationships with measurement error and censoring

Measurements of biomarkers have been used, in conjunction with those of external exposure, to provide information about the rates of human uptake, bioactivation, and detoxification of chemicals. Direct knowledge of these processes is valuable because it can reduce reliance on animal models for making extrapolations about disease risks in humans. In practice, however, valid and precise quantification of exposure—biomarker relationships has been hampered by a number of problems. These include errors in the measurement of true mean exposure and true mean biomarker levels, nonlinear exposure—biomarker relationships, background biomarker levels in unexposed individuals, and response levels that fall below analytic limits of detection. In this article we develop nonlinear mixed models and corresponding likelihood expressions that can address these concerns, and we describe maximum likelihood estimation techniques that permit valid statistical inferences to be made using standard software. The models and methods are applied to both experimental and simulated exposure—biomarker data to illustrate their utility and limitations.
Delay-jitter control in multimedia applications

The growing needs of multimedia communications are leading to new developments in providing real-time communication with guarantees. Several extensions have been proposed for different layers of the Open Systems Interconnection Reference Model to accomodate these needs. In this paper, we study methods for guaranteeing delay jitter bounds for high-speed networks in the network and application layers of this model. The method proposed for the network layer provides distributed jitter control. The method proposed for the application layer allows the destination application to control delay jitter. We use a simulation to compare the effects on delay jitter in each method for various scenarios, such as constant bit rate, cross traffic, and bursty data. In addition, the buffer space requirements for accommodating real-time channels are monitored at each node in the network.
Effects of the torso boundary and internal conductivity interfaces in electrocardiography: an evaluation of the 'infinite medium' approximation.

The analytic, eccentric spheres model of the torso was used to examine the validity of approximating the ‘infinite medium’ potential by integrating ‘finite medium potentials’ over the torso surface. Although idealized, the analytic model is sophisticated enough for all important torso conductivity and geometry parameters to be preserved in the formulation. The model generates both ‘finite medium’ potentials (for which the torso is surrounded by air) and also ‘infinite medium’ potentials (for which the outermost layer of the torso extends outward to infinity). The finite medium torso potentials were integrated over the torso surface in accordance with the approximation used by many investigators in an effort to make the surface distribution more representative of the primary cardiac sources. The resulting potential distribution was compared with the true infinite medium potential, in which the effects of internal inhomogeneities (secondary sources) were taken into account. The difference between the two representations was found to be significant, and caution should be used when interpreting such data.
USDA reference UV spectroradiometric network: Current performance and operational experience

At present the USDA Reference Spectroradiometric Network consists of 3 sites: Table Mt. CO, Lamont OK (the ARM program SGP site), and Beltsville MD. At each site we deploy and continuously operate a 1-meter cascaded additive-double Czerny-Turner scanning monochromator with a bi-alkali Photomultiplier and photon-counting detection. Lambertian fore-optic errors are less than 1% over the range of zenith angles from 0 to 80 degrees. The instruments use photon counting and make measurements not affected by stray light at 290 nm under typical conditions. The basic performance specifications of the instrument were demonstrated by a prototype at the 1997 North American UV Spectroradiometer Intercomparison. Data shown here demonstrate that these are met in routine operation.© (2002) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Power Variations in Microwave Exposure Resulting from Different Source Gases

We have observed levels of radiation leakage in a microwave atom generator that are dependent not only on the source design but also on the particular carrier gas used. Radiation leakage that is below the acceptable power density limit can be increased beyond the hazard level by simply changing the carrier gas. Researchers should be aware of our observations considering the serious health hazards of microwave exposure.
Incremental method for computing the intersection of discretely sampled m-dimensional images with n-dimensional boundaries

This paper describes an algorithm for clipping of m-dimensional objects that intersect a compact n-dimensional rectangular area. The new algorithm is an extension of a method for line clipping in three dimensions. Motivated by the need for efficient algorithms for example when comparing three-dimensional (3-D) images to each other, our method allows for the incremental computation of the subset of voxels in a discretely sampled image which are located inside a second image. Limited fields of view (rectangular regions of interest) in either image are easily supported. Application of our algorithm does not require the generation of an explicit geometrical description of the image intersection. Besides its generality with respect to the dimensions of the objects under consideration, our clipping method solves the problem of discriminating between points inside the clipping region and points on its edge, which is important when problems such as voxel intensity interpolation are only well-defined within the clipping area.
Control of radiation heat transfer through a composite window featuring ER fluid: A conceptual investigation

Radiation heat transfer control through the application of an electric field upon an Electroheological (ER) fluid based composite material is an innovative new area of research. A conceptual experiment has been conducted to study radiation heat transfer through a composite window featuring an ER fluid. The composite window is composed of two thin glass plates with a layer of ER fluid contained between them. The glass walls were transparent except for a very thin coating of an electric-conductive film which enabled the inside of the glass surfaces to serve as electrodes. The ER fluid was contained between the glass surfaces and consisted of a suspension of micron sized crystalline zeolite particles in a silicon oil. This study has demonstrated the unique capability of ER fluids to regulate and control radiation heat transfer via transmittance measurements. A semi-empirical model is developed from the experimental data to correlate the dependence of radiation transmission through ER fluids based on several physical parameters (fv, V*, and L). This model agrees reasonably well with the measured data. The results obtained in this study are very important to those concerned with the development of a thermally smart material for heat transfer control.
Biochemical and computational analyses of two phenotypically related GALT mutations (S222N and S135L) that lead to atypical galactosemia

Galactosemia is a metabolic disorder caused by mutations in the GALT gene [1,2]. We encountered a patient heterozygous for a known pathogenic H132Q mutation and a novel S222N variant of unknown significance [3]. Reminiscent of patients with the S135L mutation, our patient had loss of GALT enzyme activity in erythrocytes but a very mild clinical phenotype [3–8]. We performed splicing experiments and computational structural analyses to investigate the role of the novel S222N variant. Alamut software data predicted loss of splicing enhancers for the S222N and S135L mutations [9,10]. A cDNA library was generated from our patient׳s RNA to investigate for splicing errors, but no change in transcript length was seen [3]. In silico structural analysis was performed to investigate enzyme stability and attempt to understand the mechanism of the atypical galactosemia phenotype. Stability results are publicly available in the GALT Protein Database 2.0 [11–14]. Animations were created to give the reader a dynamic view of the enzyme structure and mutation locations. Protein database files and python scripts are included for further investigation.
Alternative management of bladder exstrophy.

Purpose of review Recent long-time outcome studies of patients with bladder exstrophy treated with primary urinary diversions or primary reconstruction force pediatric urologists to reassess the place of alternative management options in the armamentarium of bladder exstrophy treatment. Recent findings After classic ureterosigmoidostomy (USS) or Mainz II pouch, continence rates are very high even in the long-term follow-up with a mean of 50 years. In contrast, multiple procedures including bladder neck repair (BNR) were needed in the majority of patients after complete primary repair of bladder exstrophy (CPRE) to achieve normal voiding and to provide cosmetically acceptable and functional genitalia. After multiple staged repair of bladder exstrophy (MSRE), the requirements of multiple procedures including bladder augmentation to achieve urinary continence, not normal voiding, is well known. The augmentation rates published in the literature range form 0 to 82%. There is increasing concern that the risk for tumor formation might be the same for any type of inclusion of intestinal tissue in the urinary tract even without the direct exposure to the fecal stream. Summary The hope of providing normal voiding with a single operation (CPRE) might not be fulfilled even in the most skilled hands. This means that existing concerns after reconstructive techniques in bladder exstrophy regarding risk of tumor formation and BNR not standing the test of time remain important. Long-term psychosocial and sexual outcomes, including fertility of patients after reconstruction or primary diversion, will need to be taken into consideration.
Examination of Ambient Pressure Effects on Hybrid Solid Oxide Fuel Cell Turbine System Operation Using Hardware Simulation

The effect of ambient inlet air pressure variations on the compressor performance in a direct fired solid oxide fuel cell gas turbine hybrid power system has been studied using the Hybrid Performance (Hyper) project hardware simulation facility at the U.S. Department of Energy, National Energy Technology Laboratory (NETL). The Hyper facility at NETL makes use of a high speed numerical model which controls a burner and a series of pressure vessels and piping to collectively simulate a direct-fired, high-temperature fuel cell. The hardware simulating the fuel cell is integrated into the system with a modified single shaft turbine driven compressor and a pair of recuperates to provide cathode air preheat from the turbine exhaust. Orifice plates were employed at the compressor inlet of the facility to parametrically vary the inlet pressure. The compressor inlet temperature for all tests conducted was held within a 2 Kelvin range. Variation in inlet pressure was shown to have a significant effect on many hybrid system performance parameters. Some system parameters were shown to have a linear dependency on the inlet pressure, leading to the implementation of correction factors. Similar dependence of compressor discharge pressure and temperature on compressor inlet pressure was predicted by dynamic models based on isentropic compression principles. Transient operation was also impacted by changes in compressor inlet pressure. Startup profiles are shown against the compressor stall line for indication of changes in surge margin.Copyright © 2006 by ASME
Flexural pulse propagation in nonuniform elastic bars by geometric acoustics

Abstract A direct numerical procedure is developed for analyzing the refraction of a flexural wave which impinges on a finite region of variable mechanical impedance in an elastic bar. This region is approximated by a set of uniform impedance elements, regarded as Timoshenko beams, to which the methods of geometric acoustics are applied. The analysis is performed for an infinite harmonic wave train and is extended to the case of a pulse by means of numerical Fourier synthesis. Numerical results are obtained for several examples in which experiments were performed and the calculated pulses are in close agreement with those observed experimentally. It is found that the contribution of the continuing interaction between propagating and nonpropagating waves accumulates within a nonuniform region and can significantly affect the net pulses of transmission and reflection.
Efficient ab initio method for the calculation of frequency-dependent second-order optical response in semiconductors

The development of a method for calculating the frequency-dependent second harmonic generation coefficient of insulators and semiconductors based on the self-consistent linearized muffin-tin orbitals band structure method is reported. The calculations are at the independent particle level and are based on the formulation introduced by Aversa and Sipe [Phys. Rev. B 52, 14 636 (1995)]. The terms are rearranged in such a way as to exhibit explicitly all required symmetries including the Kleinman symmetry in the static limit. Computational details and convergence tests are presented. The calculated frequency-dependent ${\ensuremath{\chi}}^{(2)}(\ensuremath{-}2\ensuremath{\omega},\ensuremath{\omega},\ensuremath{\omega})$ for the zinc-blende materials GaAs, GaP and wurtzite GaN and AlN are found to be in excellent agreement with that obtained by other first-principles calculations when corrections to the local density approximation are implemented in the same manner, namely, using the ``scissors'' approach. Similar agreement is found for the static values of ${\ensuremath{\chi}}^{(2)}$ for zinc-blende GaN, AlN, BN, and SiC. The strict validity of the usual ``scissors'' operator implementation is, however, questioned. We show that better agreement with experiment is obtained when the corrections to the low-lying conduction bands are applied at the level of the Hamiltonian, which guarantees that eigenvectors are consistent with the eigenvalues. Results are presented for the frequency-dependent ${\ensuremath{\chi}}^{(2)}(\ensuremath{-}2\ensuremath{\omega},\ensuremath{\omega},\ensuremath{\omega})$ for $3C\ensuremath{-}\mathrm{S}\mathrm{i}\mathrm{C}$. The approach is found to be very efficient and flexible, which indicates that it will be useful for a wide variety of material systems including those with many atoms in the unit cell.
Analogue of the degree conjecture over function fields

Under a certain assumption, similar to Manin's conjecture, we prove an upper bound on the degree of modular parametrizations of elliptic curves by Drinfeld modular curves, which is the function field analogue of the conjectured bound over the rational numbers.
Time scale bridging in atomistic simulation of slow dynamics: viscous relaxation and defect activation

Atomistic simulation methods are known for timescale limitations in resolving slow dynamical processes. Two well-known scenarios of slow dynamics are viscous relaxation in supercooled liquids and creep deformation in stressed solids. In both phenomena the challenge to theory and simulation is to sample the transition state pathways efficiently and follow the dynamical processes on long timescales. We present a perspective based on the biased molecular simulation methods such as metadynamics, autonomous basin climbing (ABC), strain-boost and adaptive boost simulations. Such algorithms can enable an atomic-level explanation of the temperature variation of the shear viscosity of glassy liquids, and the relaxation behavior in solids undergoing creep deformation. By discussing the dynamics of slow relaxation in two quite different areas of condensed matter science, we hope to draw attention to other complex problems where anthropological or geological-scale time behavior can be simulated at atomic resolution and understood in terms of micro-scale processes of molecular rearrangements and collective interactions. As examples of a class of phenomena that can be broadly classified as materials ageing, we point to stress corrosion cracking and cement setting as opportunities for atomistic modeling and simulations.
Modeling the Shapes of Constrained Partially Inflated High-Altitude Balloons

During a balloon mission, the maximum film stresses most likely occur while the balloon is constrained by the launch spool. The focus is on shapes of very small gas volume that are representative of spool shapes and partially inflated ascent shapes where a launch collar is still attached. The balloon is constructed from long, flat, tapered sheets of 20.32-μm polyethylene that are sealed edge-to-edge to form a complete shape. Two caps are assumed to be located on top of the balloon. Load tapes are attached along the edges of the gores. The potential energy of the balloon system includes contributions due to hydrostatic pressure, film weight, load tape weight, film strain, and load tape strain. Solutions are determined that minimize the total energy subject to a volume constraint plus appropriate constraints to model nonfully deployed configurations. To model fine wrinkling in the balloon's membrane surface and to avoid compressive states, energy relaxation is employed. A number of numerical solutions are presented to illustrate the approach and provide estimates of the film stresses for these types of configurations.
Ambiguous Agreement, Functional Compensation, and Nonspecific "tu" in the Spanish of San Juan, Puerto Rico and Madrid, Spain.

Richness of subject-verb agreement is implicit in the functional compensation interpretation of variable second person /-s/ in Puerto Rican Spanish (PRS). Because /-s/ is not variable in Madrid Spanish (MS), richer agreement is assumed, and a lower rate of pronominal expression is expected. Central to this interpretation are effects associated with ambiguous marking of person on finite singular verbs. Although an increase of pronominal expression correlates to ambiguous marking for PRS speakers, a similar result has not been reported for MS speakers. Nonetheless, a varbrul analysis yields similar weights for this constraint in both dialects. Moreover, ambiguity effects are best understood as constraints on null subject variation that interact with switch reference. Identity of varbrul weights for constraints on pronominal and null subject variation in PRS and MS also supports the Constant Rate Hypothesis. However, the two dialects do show a diametrically opposed effect associated with nonspecific tu.
A distributed framework for collaborative annotation of streams

Research groups and software companies have developed a number of multimedia collaboration tools such as Access Grid and Vannotea to archive collaborative objects such as audiovisual communications and digital annotations. Most of these tools are designed to process multimedia data streams, and it is not easy for their users to extend or modify them to support other types of data streams such as those generated by earthquake sensors and medical instruments. It is challenging to design and develop a system that supports creating, sharing and replaying annotations on user specified data streams. In this paper, we make a survey of several popular collaboration and annotation tools, and then present our prototype of a distributed framework that supports collaborative annotation on generic data streams. It supports basic annotation operations on the stream data, and it also provides a set of capturing and rendering interfaces that simplify the procedure of adding support for new types of data streams.
United Mechanisms for the Generation of Low- and High-Frequency Tropical Waves. Part I: Control Experiments with Moist Convective Adjustment

To examine several mechanisms for the generation of low- and high-frequency tropical waves, numerical experiments are conducted using an idealized nine-level R21 spectral model with the original scheme of moist convective adjustment (MCA). The model prescribes globally uniform, time-independent distributions of sea surface temperatures and insolation, thereby excluding stationary waves and extratropical baroclinic waves. The idealized model, however, still produces tropical intraseasonal oscillations, superclusters, Kelvin waves, and mixed Rossby‐gravity waves. When eliminating the wind fluctuations in the parameterized surface fluxes of latent and sensible heat, the intraseasonal oscillations are profoundly weakened while other waves are not substantially weakened. Subsequently, the MCA scheme is modified to neutralize any conditionally unstable stratification that would otherwise develop during periods of nonsaturation. This modification suppresses the part of the MCA process that neutralizes, upon saturation, any preexisting unstable stratification. In spite of the presence of moisture convergence, all tropical transient waves then disappear, in contrast to the wave-CISK (conditional instability of the second kind) mechanism. The above results are consistent with the united mechanisms proposed as follows. Intraseasonal oscillations are maintained primarily through the evaporation‐wind feedback mechanism. Other waves are maintained primarily through the ‘‘saturation-triggering mechanism’’ and/or the lateral-triggering mechanism. The saturationtriggering mechanism hypothesizes that transient waves can be triggered by the intermittent onset of nonequilibrium moist convection, upon saturation, to neutralize any preexisting unstable stratification.
International Pediatric Non-Hodgkin Lymphoma Response Criteria

Purpose Response criteria are well established for adult patients with non-Hodgkin lymphoma (NHL). A revised set of response criteria in adults with NHL was recently published. However, NHL in children and adolescents involves different histologies, primary sites of disease, patterns of metastatic spread, approaches to therapy, and responses to treatment compared with adult NHL. However, there are no standardized response criteria specific to pediatric NHL. Therefore, we developed international standardized methods for assessing response to therapy in children and adolescents with NHL. Methods An international multidisciplinary group of pediatric oncologists, pathologists, biologists, and radiologists convened during and after the Third and Fourth International Childhood, Adolescent and Young Adult NHL Symposia to review existing response and outcome data, develop methods for response evaluation that reflect incorporation of more sensitive technologies currently in use, and incorporate primary and metasta...
Noninvasive pulse CO-oximetry expedites evaluation and management of patients with carbon monoxide poisoning

Abstract Purposes Pulse CO-oximetry (Rad-57; Masimo Corp, Irvine, CA) has been available since 2005. To date, all published clinical studies have focused on clinical reliability and whether the device enhances case finding through screening of various populations. This study examines whether use of pulse CO-oximetry shortens the time to diagnosis and treatment of patients with carbon monoxide (CO) poisoning. Basic Procedures Data from the joint Undersea and Hyperbaric Medical Society/Centers for Disease Control and Prevention CO poisoning surveillance system from August 2008 to July 2011 were analyzed. Of 1711 cases of CO poisoning treated with hyperbaric oxygen in the United States and reported through the system, 1606 had their initial carboxyhemoglobin (COHb) level measured by laboratory CO-oximetry and 105 by pulse CO-oximetry. Patients were selected from the laboratory CO-oximetry group to match each of the 105 patients evaluated by pulse CO-oximetry in 5 characteristics—age, sex, race/ethnicity, intent of poisoning, and occurrence of loss of consciousness. Measures of timeliness in measurement and management were compared between the 2 groups. Main Findings Patients with initial COHb measurement by pulse CO-oximetry had significantly shorter time to measurement of COHb, higher average levels of COHb, and shorter time from the end of CO exposure to the initiation of hyperbaric oxygen treatment. On average, patients evaluated by pulse CO-oximetry reached the hyperbaric chamber 1 hour faster than did patients evaluated by laboratory CO-oximetry ( P Principle Conclusions Pulse CO-oximetry is associated with more rapid diagnosis and initiation of hyperbaric oxygen therapy in CO-poisoned patients compared with laboratory CO-oximetry. The impact on clinical outcome remains to be determined.
Robust estimator for uncertain stochastic systems

Development of a robust estimator for uncertain stochastic systems under persistent excitation is presented. The given continuous-time stochastic formulation assumes norm bounded parametric uncertainties and excitations. When there are no system uncertainties, the performance of the proposed robust estimator is similar to that of the Kalman-Bucy filter and the present approach asymptotically recovers the desired optimal performance in the presence of uncertainties and or persistent excitation.
On the impact of PMU placement on observability and cross-validation

Significant investments have been made into deploying phasor measurement units (PMUs) on electric power grids worldwide. PMUs allow the state of the power system — the voltage phasor of system buses and current phasors of all incident transmission lines — to be directly measured. In some cases, it is also possible to infer the voltage and current phasors at neighboring buses and lines. Because PMUs are expensive, it is typically not possible to deploy enough PMUs to observe all phasors in a grid network [3, 6]. In this paper, we prove the NP-Completeness of four problems relating to PMU placements at a subset of system buses to achieve different goals: FullObserve, MaxObserve, FullObserve-XV, and MaxObserve-XV. FullObserve considers the minimum number of PMUs needed to observe all nodes, while MaxObserve considers the maximum number of buses that can be observed with a given number of PMUs. While the first of these two has been considered in the past, our formulation here generalizes the systems being considered. Next, FullObserve-XV and MaxObserve-XV consider these two problems under the constraints that PMUs must be placed “close” to each other so their measurements can be cross-validated. FullObserve-XV considers observing the entire network, while MaxObserve-XV considers maximizing the number of observed buses under this new constraint. Motivated by their high complexity, for each problem we investigate the performance of a suitable greedy approximation algorithm for PMU placement. Through simulations, we compare the performance of these algorithms with the optimal placement of PMUs over several IEEE bus systems as well as over synthetic graphs. In our simulations these algorithms yield results that are close to optimal — for all four placement problems, the greedy algorithms yield, on average, a PMU placement that is within 97% of optimal.
When Fraud Pays: Executive Self-Dealing and the Failure of Self-Restraint

Fraud is a generic term that encompasses the multifarious and often ingenious means by which one individual can gain an advantage over another through deliberate false suggestion, concealment, or misrepresentation of the truth. Fraudulent acts include the submitting of false claims, tampering with scales and measures, false bookkeeping, tax evasion, and intentionally lying in contractual negotiations. In ethical terms, fraud combines deliberate falsehoods with a conscious willingness to prey on the trusting nature and reliance needs of others; hence, fraud carries strong moral disapprobation. In law, fraud constitutes a defense to a breach of contract action, an affirmative cause of action in tort, and a crime.