cssi/SciSciGPT-SciSciNet huggingface dataset:
Integrated thermal-conductivity vacuum sensor

Abstract A thermal-conductivity vacuum sensor with a novel on-chip control system is presented. The sensing structure is a small circuit suspended over a cavity etched in the (100)-oriented silicon substrate. An integrated control system maintains a constant temperature difference between this thermally isolated sensor and the substrate. The control loop allows for a digitally adjustable operating temperature of the sensor. The sensitive range of the prototype vacuum sensor extends from 0.8 Pa (6 mtorr) to approximately 9.2 × 104 Pa (690 torr). The system has been fabricated in a completely unmodified foundry CMOS process, provides a current output, dissipates only 5 mW of power, and occupies an area of approximately 0.3 mm2.
Fuel Conditioning Facility Electrorefiner Model Predictions versus Measurements

Abstract Electrometallurgical treatment of spent nuclear fuel is performed in the Fuel Conditioning Facility (FCF) at the Idaho National Laboratory (INL) by electrochemically separating uranium from the fission products and structural materials in a vessel called an electrorefiner (ER). To continue processing without waiting for sample analyses to assess process conditions, an ER process model predicts the composition of the ER inventory and effluent streams via multi-component, multi-phase chemical equilibrium for chemical reactions and a numerical solution to differential equations for electro-chemical transport. The results of the process model were compared to the electrorefiner measured data.
Extensive hydrated silica materials in western Hellas Basin, Mars

Abstract Near-infrared spectral data indicate the presence of hydrated, poorly crystalline silica where high bulk silica contents have been previously identified in Hellas Basin. No other aqueous phases are identified in these regions and the deposits may be nearly pure. The silica-bearing surfaces are sporadically exposed along a 650 km stretch of the western basin rim within a limited elevation range and display a variety of surface textures suggesting that the materials have been reworked, but not transported large distances. The high abundances and lack of associated aqueous phases indicate that high water to rock ratios were present in the region during the Noachian period but without elevated temperatures or for durations necessary for quartz diagenesis. The silica-bearing materials may have formed via direct precipitation from silica saturated groundwater sources, although other formation mechanisms are also plausible.
Robust anomaly detection in dynamic networks

We propose two robust methods for anomaly detection in dynamic networks in which the properties of normal traffic evolve dynamically. We formulate the robust anomaly detection problem as a binary composite hypothesis testing problem and propose two methods: a model-free and a model-based one, leveraging techniques from the theory of large deviations. Both methods require a family of Probability Laws (PLs) that represent normal properties of traffic. We devise a two-step procedure to estimate this family of PLs. We compare the performance of our robust methods and their vanilla counterparts, which assume that normal traffic is stationary, on a network with a diurnal normal pattern and a common anomaly related to data exfiltration. Simulation results show that our robust methods perform better than their vanilla counterparts in dynamic networks.
The First Silver-Catalyzed Three-Component Coupling of Aldehyde, Alkyne, and Amine

Silver iodide catalyzed the three-component coupling of aldehyde, alkyne, and amines to generate propargylic amines with high efficiency in water. The silver-catalyzed reaction is especially effective for reactions involving aliphatic aldehyde. No additional cocatalyst or activator is required.
A partially collisional model of the Titan hydrogen torus

Occasional collision effects are encompassed by the present numerical model of atomic hydrogen densities in Titan's hydrogen torus, which is noted to be azimuthally symmetric; the torus density peaks sharply at Titan's orbit, and rapidly decreases in the both radially outward and perpendicular directions. Collisions of Saturnian atoms with the torus population produce a corona. Without this coronal population, the torus model would not reproduce the Voyager 2 Lyman-alpha intensities. These observations may nevertheless be modelled by a torus-plus-corona model that also reconciles the Pioneer 11 torus observations with those of the two Voyager spacecraft.
Divisional performance measurement and transfer pricing for intangible assets

This paper examines the effectiveness of three transfer pricing methodologies for an intangible asset that is developed through bilateral, sequential investment. In general, a royalty-based transfer price that can be renegotiated provides better investment incentives than either a non-negotiable royalty-based transfer price or a purely negotiated transfer price, and in some cases induces first-best investment. This result contrasts with previous research that finds that the inability to limit renegotiation of initial contracts reduces investment efficiency. Further, I examine how tax transfer pricing rules inform optimal internal transfer prices when the firm decouples internal and external transfer prices.
Synthesis and Some Cycloaddition Reactions of 2-(Triisopropylsilyloxy)acrolein

[reaction: see text]2-(Triisopropylsilyloxy)acrolein is easily prepared by the reaction of triisopropylsilyl triflate and 2-methoxy-2-methyl-[1,3]dioxan-5-one in the presence of triethylamine. This dienophile reacts with selected dienes in the presence of catalytic amounts of scandium triflate to afford products that are formally 4 + 3 cycloadducts. An exception is seen in the case of butadiene, where only a 4 + 2 cycloadduct is observed.
Are long-term wage elasticities of labor supply more negative than short-term ones?

Standard models imply that the wage-elasticity of labor supply is more negative the longer a wage change lasts. I observe decreasing daily hours during short-term wage increases, but not during a long-term one: daily income goals adjusted in the long-term.
Analysis of seafloor seismograms of the 2003 Tokachi-Oki earthquake sequence for earthquake early warning

[1] Earthquake Early Warning (EEW) algorithms estimate the magnitude of an underway rupture from the first few seconds of the P-wave to allow hazard assessment and mitigation before the S-wave arrival. Many large subduction-zone earthquakes initiate 50–150 km offshore, potentially allowing seafloor instruments sufficient time to identify large ruptures before the S-waves reach land. We tested an EEW algorithm using accelerograms recorded offshore Hokkaido in the region of the 2003 Mw 8.1 Tokachi-Oki earthquake and its aftershocks. A wavelet transform of the first ∼4 s of the P-wave concentrates information about earthquake magnitude from both waveform amplitude and frequency content. We find that wavelets with support of a few seconds provide discriminants for EEW that are both accurate enough to be useful and superior to peak acceleration or peak velocity. Additionally, we observe a scaling of wavelet coefficient magnitude above Mw 6.0 indicating that, at least for the mainshock (Mw 8.1) and largest aftershock (Mw 7.1), the final size of a rupture could have been estimated from the initial portion of the seismogram.
Social norms and aspirations: age of marriage and education in rural India

Summary Using a unique dataset that I collected in three villages in semi-arid India, I analyze the role of perceived returns to education and social norms regarding the ideal age of marriage in the educational plans, i.e., aspirations, parents have for their children. I show that perceptions of the ideal age of marriage significantly constrain the education that parents aspire to have for their daughters, but not their sons. Furthermore, aspirations are sensitive to the perceived returns to higher education in the case of boys, but not in the case of girls.
Novel routes to fluorinated ethers containing a fluorosulfonyl group

Abstract The chloroxy compounds ClOCF 2 CFXSO 2 F (X=F, CF 3 ) have been reacted with several simple olefins to give ethers. In the case of unsymmetrical olefins the reaction mainly follows an electrophilic cis addition with the positive polarized chlorine adding in a Markovnikov manner. One example of the conversion of a sulfonyl fluoride to its corresponding acid is given. The latter gives the respective sulfonyl chloride with phosphorus pentachloride.
Social stress and community psychology

Two questions that embrarrass community psychologists are: “What do community psychologists do?” “What’s the difference between community psychology and clinical psychology?” A conceptual model is proposed to help to find answers to these questions. The model describes a process whereby psychosocial stress leads to psychopathology. The argument is developed that the apparently disparate activities of community psychologists are uniformly directed at undermining the stress process but, given the complexity of this process, vary because they tackle it at different points.
Interacting electrons in quantum dots

Abstract The ground states of N-electron parabolic quantum dots in the presence of a perpendicular magnetic field are investigated. Rigorous lower bounds to the ground-state energies are obtained. It is shown that our lower bounds agree well with the results of exact diagonalization. Analytic results for the lower bounds to the ground-state energies of the quantum dots in a strong magnetic field (known as electron molecule) agree very well with numerically calculated lower bounds.
Polyakov Loops in Strongly-Coupled Plasmas with Gravity Duals

We study the properties of the Polyakov loop in strongly coupled gauge plasmas that are conjectured to be dual to five-dimensional theories of gravity coupled to a nontrivial single scalar field. We find a gravity dual that can describe the thermodynamic properties and also the expectation value of the Polyakov loop in the deconfined phase of quenched SU(3) QCD up to 3Tc.
A new highly selective calix[4]crown-6 fluorescent caesium probe

We have synthesized 1,3-alternate di-deoxygenated calix[4](9-cyano-10-anthrylmethyl)benzocrown-6, 1 and 1,3-alternate calix[4](9-cyano-10-anthrylmethyl)benzocrown-6, 2 as the second generation of caesium selective fluorescent probes; probe 1 shows 54-fold fluorescence enhancement upon caesium complexation while 2 exhibits only 8-fold enhancement; the selectivity ratios for 1 to complex caesium ion over potassium and rubidium (KCs/KK and KCs/KRb) are ca. 10 fold higher than those of 2 for the same ions; the observed selectivity ratios are consistent with data reported for other 1,3-alternate calix[4]crown-6 derivatives.
Electrochemical measurement of the surface alloying kinetics of underpotentially deposited Ag on Au(111).

The cyclic voltammetry characterizing underpotential deposition (UPD) of Ag onto Au(111) varies in the literature with respect to the characteristic UPD peaks in both position and number. Rooryck et al.(1) confirmed that the discrepancy in terms of peak position, specifically the initial UPD to which a third of a monolayer of deposition is attributed, is due to a variation in the quality of the surface. Clean, smooth Au(111) surfaces yield a peak position of 0.53 V vs Ag0/Ag+, while rough disordered surfaces yield a peak position of 0.61 V vs Ag0/Ag+. Repetitive potential cycling in the UPD region resulted in a gradual shift in peak position, with time as the deposited Ag alloyed with, and was stripped from the surface leaving vacancies. We provide a methodology for tracking the rate at which UPD Ag alloys with the Au(111) surface without the use of continuous potential cycling. A simple kinetic model is developed for the surface alloying of Ag on Au(111), from which we extract an activation barrier and a...
A tractable POMDP for a class of sequencing problems

We consider a partially observable Markov decision problem (POMDP) that models a class of sequencing problems. Although POMDPs are typically intractable, our formulation admits tractable solution. Instead of maintaining a value function over a highdimensional set of belief states, we reduce the state space to one of smaller dimension, in which grid-based dynamic programming techniques are effective. We develop an error bound for the resulting approximation, and discuss an application of the model to a problem in targeted advertising.
Reactive Oxygen Species Originating From Mitochondria Regulate the Cardiac Sodium Channel

Rationale:Pyridine nucleotides regulate the cardiac Na+ current (INa) through generation of reactive oxygen species (ROS). Objective:We investigated the source of ROS induced by elevated NADH. Methods and Results:In human embryonic kidney (HEK) cells stably expressing the cardiac Na+ channel, the decrease of INa (52±9%; P<0.01) induced by cytosolic NADH application (100 μmol/L) was reversed by mitoTEMPO, rotenone, malonate, DIDS (4,4′-diisothiocyanatostilbene-2,2′-disulfonic acid), PK11195, and 4′-chlorodiazepam, a specific scavenger of mitochondrial superoxide and inhibitors of the mitochondrial complex I, complex II, voltage-dependent anion channels, and benzodiazepine receptor, respectively. Anti–mycin A (20 μmol/L), a complex III inhibitor known to generate ROS, decreased INa (51±4%, P<0.01). This effect was blocked by NAD+, forskolin, or rotenone. Inhibitors of complex IV, nitric oxide synthase, the NAD(P)H oxidases, xanthine oxidases, the mitochondrial permeability transition pore, and the mitochond...
Circuit principles and weak pigeonhole variants

This paper considers the relational versions of the surjective, partial surjective, and multifunction weak pigeonhole principles for PV, @?"1^b, @?"1^b, and B(@?"1^b) formulas as well as relativizations of these formulas to higher levels of the bounded arithmetic hierarchy. We show that the partial surjective weak pigeonhole principle for @?"1^b formulas implies that for each k there is a string of length 2^2^n^^^k which is hard to block-recognize by circuits of size n^k. These principles in turn imply the partial surjective principle for @?"1^b formulas. We show that the surjective weak pigeonhole principle for B(@?"1^b) formulas in S"2^1 implies our hard-string principle which in turn implies the surjective weak pigeonhole principle for @?"1^b formulas. We introduce a class of predicates corresponding to poly-log length iterates of polynomial time computable predicates and show that over S"2^1, the multifunction weak pigeonhole principle for such predicates is equivalent to an ''iterative'' circuit block-recognition principle. A consequence of this is that if S"2^1 proves this principle then RSA is vulnerable to polynomial time attacks.
Domain Topology of Micron-Scale, Ferromagnetic Pancakes

Planar, micron-scale ellipses patterned from 700A-thick Co films exhibit nearly complete suppression of hysteresis when magnetized in- plane along their short axes. Using a combination of Magnetic Force Microscopy and Vibrating Sample Magnetometry, we find that the suppression of hysteresis is associated with the continuous deformation of a dipole field configuration. The presence of hysteresis for in-plane, long-axis magnetization is associated with transitions between topologically inequivalent configurations.
Missing momentum reconstruction and spin measurements at hadron colliders

We study methods for reconstructing the momenta of invisible particles in cascade decay chains at hadron colliders. We focus on scenarios, such as SUSY and UED, in which new physics particles are pair produced. Their subsequent decays lead to two decay chains ending with neutral stable particles escaping detection. Assuming that the masses of the decaying particles are already measured, we obtain the momenta by imposing the mass-shell constraints. Using this information, we develop techniques of determining spins of particles in theories beyond the standard model. Unlike the methods relying on Lorentz invariant variables, this method can be used to determine the spin of the particle which initiates the decay chain. We present two complementary ways of applying our method by using more inclusive variables relying on kinematic information from one decay chain, as well as constructing correlation variables based on the kinematics of both decay chains in the same event.
Evaluation of the performance of error-correcting codes on a Gilbert channel

Presents a combinatorial analysis to derive a closed-form expression for the number of transmission errors that occur in a block transmitted through a Gilbert channel. This expression simplifies the computations needed to investigate the tradeoffs among the decoding error probability, degree of interleaving, and the error-correction ability of a code. The authors illustrate how a designer may apply the method to determine different combinations of the degree of interleaving and error correction ability to achieve a specified decoding error rate. >
Proteomics and bioinformatics strategies to design countermeasures against infectious threat agents.

The potential devastation resulting from an intentional outbreak caused by biological warfare agents such as Brucella abortus and Bacillus anthracis underscores the need for next generation vaccines. Proteomics, genomics, and systems biology approaches coupled with the bacterial ghost (BG) vaccine delivery strategy offer an ideal approach for developing safer, cost-effective, and efficacious vaccines for human use in a relatively rapid time frame. Critical to any subunit vaccine development strategy is the identification of a pathogen's proteins with the greatest potential of eliciting a protective immune response. These proteins are collectively referred to as the pathogen's immunome. Proteomics provides high-resolution identification of these immunogenic proteins using standard proteomic technologies, Western blots probed with antisera from infected patients, and the pathogen's sequenced and annotated genome. Selected immunoreactive proteins can be then cloned and expressed in nonpathogenic Gram-negativ...
Abelian hidden sectors at a GeV

We discuss mechanisms for naturally generating GeV-scale hidden sectors in the context of weak-scale supersymmetry. Such low mass scales can arise when hidden sectors are more weakly coupled to supersymmetry breaking than the visible sector, as happens when supersymmetry breaking is communicated to the visible sector by gauge interactions under which the hidden sector is uncharged, or if the hidden sector is sequestered from gravity-mediated supersymmetry breaking. We study these mechanisms in detail in the context of gauge and gaugino mediation, and present specific models of Abelian GeV-scale hidden sectors. In particular, we discuss kinetic mixing of a U(1){sub x} gauge force with hypercharge, singlets or bi-fundamentals which couple to both sectors, and additional loop effects. Finally, we investigate the possible relevance of such sectors for dark matter phenomenology, as well as for low- and high-energy collider searches.
Spin Wave Magnetic NanoFabric: A New Approach to Spin-Based Logic Circuitry

We describe a magnetic nanofabric, which may provide a route to building reconfigurable spin-based logic circuits compatible with conventional electron-based devices. A distinctive feature of magnetic nanofabric is that a bit of information is encoded into the phase of the spin wave signal. This makes it possible to transmit information without the use of electric current and to utilize wave interference for useful logic functionality. The basic elements include voltage-to-spin-wave and wave-to-voltage converters, spin waveguides, a spin wave modulator, and a magnetoelectric cell. We illustrate the performance of the basic elements by experimental data and the results of numerical modeling. The combination of the basic elements leads us to construct magnetic circuits for NOT and majority logic gates. Logic gates such as AND, OR, NAND, and NOR are shown as the combination of NOT and reconfigurable majority gates. Examples of computational architectures such as a multibit processor and a cellular nonlinear network are described. The main advantage of the proposed magnetic nanofabric is its ability to realize logic gates with fewer devices than in CMOS-based circuits. Potentially, the area of the elementary reconfigurable majority gate can be scaled down to 0.1 mum2. We also discuss the disadvantages and limitations of the magnetic nanofabric.
The VLBA Calibrator Survey—VCS1

A catalog containing milliarcsecond-accurate positions of 1332 extragalactic radio sources distributed over the northern sky is presented—the Very Long Baseline Array Calibrator Survey (VCS1). The positions have been derived from astrometric analysis of dual-frequency 2.3 and 8.4 GHz VLBA snapshot observations; in a majority of cases, images of the sources are also available. These radio sources are suitable for use in geodetic and astrometric experiments, and as phase-reference calibrators in high-sensitivity astronomical imaging. The VCS1 is the largest high-resolution radio survey ever undertaken and triples the number of sources available to the radio astronomy community for VLBI applications. In addition to the astrometric role, this survey can be used in active galactic nuclei, Galactic, gravitational lens, and cosmological studies. Subject headings: astrometry — radio continuum: general — reference systems — surveys — techniques: interferometric On-line material: machine-readable tables
Transient and steady-state velocity of domain walls for a complete range of drive fields

Approximate analytic solutions for transient and steady-state 180° domain-wall motion in bulk magnetic material are obtained from the dynamic torque equations with a Gilbert damping term. The results for the Walker region in which the transient solution approaches the familiar Walker steady-state solution are presented in a slightly new form for completeness. An analytic solution corresponding to larger drive fields predicts an oscillatory motion with an average value of the velocity which decreases with drive field for reasonable values of the damping parameter. These results agree with those obtained by others from a computer solution of the torque equation and those obtained by others with the assumption of a very large anisotropy field.
Design, performance, and extensions of the RAM-DFE architecture

The design and performance of an adaptive RAM-Decision feedback equalizer integrated circuit (RAM-DFE IC) for magnetic recording channels is presented. The 0.8 /spl mu/m BICMOS digital chip has been integrated with discrete analog components in a 54 Mbps read channel. Description of the IC implementation details techniques to reduce latency and outlines tradeoffs between performance and complexity. In an effort to achieve higher throughput, alternative decision feedback loop architectures based on look-ahead computation are evaluated. A hybrid RAM/linear architecture is found to approach 150 Mbps throughput with implementational advantages over both RAM and linear feedback filters. >
Intercomparison of Soil Moisture Memory in Two Land Surface Models

Abstract A heavy rain or a dry period can produce an anomaly in soil moisture, and the dissipation of this anomaly may take weeks to months. It is important to understand how land surface models (LSMs) used with atmospheric general circulation models simulate this soil moisture “memory,” because this memory may have profound implications for long-term weather prediction through land–atmosphere feedback. In order to understand better the effect of precipitation and net radiation on soil moisture memory, the NASA Seasonal-to-Interannual Prediction Project (NSIPP) Catchment LSM and the Mosaic LSM were both forced with a wide variety of idealized climates. The imposed climates had average monthly precipitation ranging from 15 to 500 mm and monthly net radiations (in terms of water equivalent) ranging from 20 to 400 mm, with consequent changes in near-surface temperature and humidity. For an equivalent water holding capacity, the two models maximize memory in distinctly different climate regimes. Memory in the...
A model-based approach to attention and sensory integration in postural control of older adults

We conducted a dual-task experiment that involved information processing (IP) tasks concurrent with postural perturbations to explore the interaction between attention and sensory integration in postural control in young and older adults. A postural control model incorporating sensory integration and the influence of attention was fit to the data, from which parameters were then obtained to quantify the interference of attention on postural control. The model hypothesizes that the cognitive processing and integration of sensory inputs for balance requires time, and that attention influences this processing time, as well as sensory selection by facilitating specific sensory channels. Performing a concurrent IP task had an overall effect on the time delay. Differences in the time delay of the postural control model were found for the older adults. The results suggest enhanced vulnerability of balance processes in older adults to interference from concurrent cognitive IP tasks.
Effects of skeletal unloading on the vasomotor properties of the rat femur principal nutrient artery

Spaceflight and prolonged bed rest induce deconditioning of the cardiovascular system and bone loss. Previous research has shown declines in femoral bone and marrow perfusion during unloading and with subsequent reloading in hindlimb-unloaded (HU) rats, an animal model of chronic disuse. We hypothesized that the attenuated bone and marrow perfusion may result from altered vasomotor properties of the bone resistance vasculature. Therefore, the purpose of this study was to determine the effects of unloading on the vasoconstrictor and vasodilator properties of the femoral principal nutrient artery (PNA), the main conduit for blood flow to the femur, in 2 wk HU and control (CON) rats. Vasoconstriction of the femoral PNA was assessed in vitro using norepinephrine, phenylephrine, clonidine, KCl, endothelin-1, arginine vasopressin, and myogenic responsiveness. Vasodilation through endothelium-dependent [acetylcholine, bradykinin, and flow-mediated dilation (FMD)] and endothelium-independent mechanisms [sodium nitroprusside (SNP) and adenosine] were also determined. Vasoconstrictor responsiveness of the PNA from HU rats was not enhanced through any of the mechanisms tested. Endothelium-dependent vasodilation to acetylcholine (CON, 86 ± 3%; HU, 48 ± 7% vasodilation) and FMD (CON, 61 ± 9%; HU, 11 ± 11% vasodilation) were attenuated in PNAs from HU rats, while responses to bradykinin were not different between groups. Endothelium-independent vasodilation to SNP and adenosine were not different between groups. These data indicate that unloading-induced decrements in bone and marrow perfusion and increases in vascular resistance are not the result of enhanced vasoconstrictor responsiveness of the bone resistance arteries but are associated with reductions in endothelium-dependent vasodilation.
A novel caesium selective fluorescent chemosensor

A novel caesium selective fluorescent chemosensor has been designed and synthesized; the chemosensor exhibited a selective fluorescent enhancement in the presence of other alkali metal ions.
The Long-Haul Effects of Interest Arbitration: The Case of New York State’s Taylor Law

The authors examine debates about the effects of mandatory interest arbitration on police and firefighters in New York State under the Taylor Law from 1974 to 2007. Comparing experience with interest arbitration in the first three years after the law was adopted with experiences from 1995 to 2007, the authors find that no strikes occurred under arbitration and that rates of dependence on arbitration declined considerably. Moreover, the effectiveness of mediation prior to and during arbitration remained high, the tripartite arbitration structure continued to foster discussion of options for resolution among arbitration panel members, and wage increases awarded under arbitration matched those negotiated voluntarily by the parties. Econometric estimates of the effects of interest arbitration on wage changes in a national sample suggest wage increases differed little in states with arbitration from those without it. The authors therefore propose a role for interest arbitration in national labor policy.
Aqueous N-Heterocyclization of Primary Amines and Hydrazines with Dihalides: Microwave-Assisted Syntheses of N-Azacycloalkanes, Isoindole, Pyrazole, Pyrazolidine, and Phthalazine Derivatives

The synthesis of nitrogen-containing heterocycles from alkyl dihalides (ditosylates) and primary amines and hydrazines via a simple and efficient cyclocondensation in an alkaline aqueous medium that occurs under microwave irradiation is described. This improved greener synthetic methodology provides a simple and straightforward one-pot approach to the synthesis of a variety of heterocycles, such as substituted azetidines, pyrrolidines, piperidines, azepanes, N-substituted 2,3-dihydro-1H-isoindoles, 4,5-dihydropyrazoles, pyrazolidines, and 1,2-dihydrophthalazines.
Determination of Love's Number from Satellite Observations

Determination of Love number of earth from variations of orbital inclinations of satellites
Mechanism and utility of the dirhenium decacarbonyl catalyzed formation of silyl ethers

Abstract A mechanism for dirhenium decacarbonyl catalyzed formation of silyl ethers is proposed. This reaction is a good alternative to the standard silylation procedure involving the use of more expensive silyl chlorides; even tertiary silyl ethers are readily formed.
Effective maintenance practices to manage system aging

A study for the Nuclear Regulatory Commission was recently undertaken to identify effective maintenance practices that could be adapted by the nuclear industry in the United States to assist in managing the aging degradation of plant systems and components. Four organizations were examined to assess the influence of maintenance programs on addressing the system and component aging degradation issues. An effective maintenance program was found to be essential to the management of system and component aging. Four key elements of an effective maintenance program that are important to an aging management were identified: the selection of critical systems and components; the development of an understanding of aging through the collection and analysis of equipment performance information; the development of appropriate preventive and predictive maintenance tasks to manage equipment and system aging degradation; and the use of feedback mechanisms to continuously improve the management of aging systems and components. These elements were found to be common to all four organizations. >
Genetic basis of congenital generalized lipodystrophy

Congenital generalized lipodystrophy (CGL) is an autosomal recessive disorder characterized by extreme lack of body fat and severe insulin resistance since birth. Recently, mutations have been reported in 1-acylglycerol-3-phosphate-O-acyltransferase 2 (AGPAT2) and Berardinelli-Seip congenital lipodystrophy 2 (BSCL2 or Seipin) genes in affected subjects from pedigrees linked to chromosomes 9q34 and 11q13, respectively. The AGPAT2 catalyses the acylation of the lysophosphatidic acid at the sn-2 position to form phosphatidic acid, a key intermediate in the biosynthesis of triacylglycerol and glycerophospholipids. High expression of AGPAT2 mRNA in adipose tissue compared to other isoforms suggests that the mutations might affect the adipose tissue the most. The function of BSCL2 remains unknown. Several CGL pedigrees reveal no mutation in either of the above genes and are not linked to these loci, suggesting additional genetic loci for CGL. Thus, several distinct mechanisms can lead to extreme lack of adipose tissue in humans and cause CGL.
Stellar Occultation Observations of Saturn's North-Polar Temperature Structure

Abstract We have observed a stellar occultation of GSC5249-01240 by Saturn's north polar region on November 20, 1995 from NASA's Infrared Telescope Facility (IRTF). This is the first recorded occultation by the polar region of a giant planet. The occulted region extends 88 km in vertical height and 660 km in horizontal length, over a region from 82.5° to 85° in planetocentric latitude and from 20° to 30° in planetocentric longitude. Based on isothermal model fits to the light curve, we find an equivalent isothermal temperature of 130 ± 10 K at a pressure level of 1.6 ± 0.1 μbar, which corresponds to a half-light latitude of 83.2 ± 0.2° and longitude of 24.1 ± 0.5°. Using numerical inversion procedures, we have retrieved the temperature profile of the occulted region, which suggests an increase in temperature (with radius) of 14.5 K between 6 and 10 μbar. We also find temperature fluctuations of 1 to 5 K along the path probed by the occultation; if the observed temperature gradients of these fluctuations apply to the vertical direction only, then this region is super-adiabatic. More likely, these thermal gradients are due to a combination of diffractive scintillations and horizontal temperature variations. Given that isothermal model fits and numerical inversions cannot separate individual contributions to observed temperature gradients, such as from vertical variations, horizontal variations, and scintillations, this occultation requires further study.
DataStager: scalable data staging services for petascale applications

Known challenges for petascale machines are that (1) the costs of I/O for high performance applications can be substantial, especially for output tasks like checkpointing, and (2) noise from I/O actions can inject undesirable delays into the runtimes of such codes on individual compute nodes. This paper introduces the flexible `DataStager' framework for data staging and alternative services within that jointly address (1) and (2). Data staging services moving output data from compute nodes to staging or I/O nodes prior to storage are used to reduce I/O overheads on applications' total processing times, and explicit management of data staging offers reduced perturbation when extracting output data from a petascale machine's compute partition. Experimental evaluations of DataStager on the Cray XT machine at Oak Ridge National Laboratory establish both the necessity of intelligent data staging and the high performance of our approach, using the GTC fusion modeling code and benchmarks running on 1000+ processors.
Estimating all pairs shortest paths in restricted graph families: a unified approach

In this paper we show that a very simple and efficient approach can be used to solve the all pairs almost shortest path problem on the class of weakly chordal graphs and its different subclasses. Moreover, this approach works well also on graphs with small size of largest induced cycle and gives a unified way to solve the all pairs almost shortest path and all pairs shortest path problems on different graph classes including chordal, strongly chordal, chordal bipartite, and distance-hereditary graphs.
Actomyosin contractility and Discs large contribute to junctional conversion in guiding cell alignment within the Drosophila embryonic epithelium

Proper control of epithelial morphogenesis is vital to development and is often disrupted in disease. After germ band extension, the cells of the Drosophila ventral embryonic epidermis are packed in a two-dimensional polygonal array. Although epithelial cell rearrangements are being studied productively in several tissues, the ventral epidermis is of particular interest as the final cell arrangement is, uniquely, far from equilibrium. We show that over the course of several hours, a subset of cells within each parasegment adopts a rectilinear configuration and aligns into parallel columns. Live imaging shows that this is accomplished by the shrinkage of select cell interfaces, as three-cell junctions are converted to four-cell junctions. Additionally, we show that non-muscle Myosin II and the polarity proteins Discs large (Dlg) and Bazooka are enriched along cell interfaces in a complex but reproducible pattern that suggests their involvement in junctional conversion and cell alignment. Indeed, depletion of Myosin II or dlg disrupts these processes. These results show that tight spatial regulation of actomyosin contractility is required to produce this high-energy arrangement of cells.
The Promise of Known-good-die Technologies

The yield and reliability requirements for multichip packaging (MCP) applications have provided the major impetus for the development of known-good-die (KGD) technology solutions. KGD technology includes components of electrical contact, mechanical fixturing, IC design, test and automation. This paper will provide an overview of the KGD market and KGD technologies currently available in the industry. Die-Level-Burn-In (DLBI) approaches based on temporary bare die carriers are emerging in the industry. The goal for carrier development for test and burn-in is a cost-effective, bare die contact and fixturing approach that accommodates both peripheral and array contacts as well as wire bond and bumped die. For semiconductor manufacturers, possibility of conducting burn-in in wafer form is more attractive and holds the promise of reducing the total cost to manufacture die, regardless of the packaging destination. This paper will provide a review of KGD technology solutions which span a range of maturity from conceptual to qualified for production.
Stellar mass-to-light ratios and the Tully-Fisher relation

We have used a suite of simplified spectrophotometric spiral galaxy evolution models to argue that there are substantial variations in stellar mass-to-light (M/L) ratios within and among galaxies, amounting to factors of between 3 and 7 in the optical and factors of 2 in the near-infrared. Our models show a strong correlation between stellar M/L and the optical colors of the integrated stellar populations. Under the assumption of a universal spiral galaxy initial mass function (IMF), relative trends in model stellar M/L with color are robust to uncertainties in stellar population and galaxy evolution modeling, including the effects of modest bursts of star formation. Errors in the dust-reddening estimates do not strongly affect the final derived stellar masses of a stellar population. We examine the observed maximum disk stellar M/L ratios of a sample of spiral galaxies with accurate rotation curves and optical and near-infrared luminosity profiles. From these observed maximum disk M/L ratios we conclude that a Salpeter IMF has too many low-mass stars per unit luminosity but that an IMF similar to the Salpeter IMF at the high-mass end with less low-mass stars (giving stellar M/L ratios 30% lower than the Salpeter value) is consistent with the maximum disk constraints. Trends in observed maximum disk stellar M/L ratios with color provide a good match to the predicted model relation, suggesting that the spiral galaxy stellar IMF is universal and that a fraction of (particularly high surface brightness) spiral galaxies may be close to maximum disk. We apply the model trends in stellar M/L ratio with color to the Tully-Fisher (T-F) relation. We find that the stellar mass T-F relation is relatively steep, has modest scatter, and is independent of the passband and color used to derive the stellar masses, again lending support for a universal IMF. The difference in slope between the optical (especially blue) and near-infrared T-F relations is due to the combined effects of dust attenuation and stellar M/L variations with galaxy mass. Assuming the Hubble Space Telescope Key Project distance to the Ursa Major Cluster and neglecting the (uncertain) molecular gas fraction, we find that the baryonic T-F relation takes the form Mbaryon V3.5 (with random and systematic 1 σ slope errors of ~0.2 each) when using a bisector fit and rotation velocities derived from the flat part of the rotation curve. Since we have normalized the stellar M/L ratios to be as high as can possibly be allowed by maximum disk constraints, the slope of the baryonic T-F relation will be somewhat shallower than 3.5 if all disks are substantially submaximal.
Iterative frequency-domain channel estimation and equalization for single-carrier transmissions without cyclic-prefix

Compared to conventional time-domain equalization, frequency-domain equalization (FDE) presents a computationally efficient alternative for the reception of single carrier (SC) transmissions. In this paper, we consider iterative FDE (IFDE) with explicit frequency-domain channel estimation (FDCE) for non-cyclic-prefixed SC systems. First, an improved IFDE algorithm is presented based on soft iterative interference cancellation. Second, a new adaptive FDCE (AFDCE) algorithm based on per-tone Kalman filtering is proposed to track and predict the frequency-domain channel coefficients. The AFDCE algorithm employs across-tone noise reduction, exploits temporal correlation between successive blocks, and adaptively updates the auto-regressive model coefficients, bypassing the need for prior knowledge of channel statistics. Finally, block-overlapping is used to facilitate the joint operation of IFDE and AFDCE. Simulation results show that, compared to related IFDE and adaptive channel estimation schemes, the proposed schemes offer lower mean-square error (MSE) in channel prediction, lower bit error rate (BER) after decoding, and robustness to non-stationary channels.
Termination fees in mergers and acquisitions

Abstract The paper provides evidence on the effects of including a target termination fee in a merger contract. I test the implications of the hypothesis that termination fees are used by self-interested target managers to deter competing bids and protect “sweetheart” deals with white knight bidders, presumably resulting in lower premiums for target shareholders. An alternative hypothesis is that target managers use termination fees to encourage bidder participation by ensuring that the bidder is compensated for the revelation of valuable private information released during merger negotiations. My empirical evidence demonstrates that merger deals with target termination fees involve significantly higher premiums and success rates than deals without such clauses. Furthermore, only weak support is found for the contention that termination fees deter competing bids. Overall, the evidence suggests that termination fee use is at least not harmful, and is likely beneficial, to target shareholders.
In-Situ TEM Study of Domain Propagation in Ferroelectric Barium Titanate, and Its Role in Fatigue

We have conducted in-situ transmission electron microscopy (TEM) experiments on thinned single crystal barium titanate in order to study the effects of applied electric field, temperature, electron beam irradiation and UV irradiation on domain nucleation and propagation. We observe two basic modes of domain wall motion; (i) a lateral motion which uniformly widens or narrows the total domain width; (ii) a “zipping” motion in which one end of a domain narrows to a point, which then propagates lengthwise, widening (or narrowing) the domain behind it. Both domain creation and destruction can occur by this latter process. When cooling from above Tc, domain growth usually occurs by the “zipping” motion. We believe that both the lateral and “zipping” modes of motion are related. The “zipping” mode tends to occur in the presence of inhomogeneous long-range strain fields, or when trapped charges are present locally. In some instances, the trapped charge is strong enough to show significant image contrast in bright-field. Domain motion, initiated by heat, electric fields or UV irradiation, moves such charges. A model of domain motion is presented which shows how displacement charge can be injected into the ferroelectric, and which may contribute to the fatigue of these materials.
Wind Tunnel Boundary Corrections for a Full Scale 1903 Wright Flyer Replica

A panel code is developed in order to assess and correct wind-tunnel boundary interferences during a test of a full-scale reproduction of the 1903 Wright Flyer in the Langley Full-Scale Tunnel (LFST). The LFST is a very large, low-speed wind tunnel with a 3 4-open test section. The principal concerns relating to boundary corrections are the relatively large size of the replica relative to the test-section dimensions, coupled with the lack of modern correction techniques for aeronautical testing in open-jet test sections. The Flyer is represented either by simple lifting surfaces, with the accuracy of the representation validated by direct calculations using the panel code CMARC, or by an array of simple horseshoe vortex singularities. Vortex ring panels are used in the boundary correction code. The solution starts by solving the flow in a closed test section in order to obtain the flow properties on the boundaries. An iterative method, based on the one-step method employed in adaptive wall wind-tunnel work, is then used to adapt the boundary geometry to a constant-pressure condition. Finally the boundary interference is obtained by calculating the velocities induced in the test region by the boundary singularities. Results are presented for different test-section boundary configurations: fully closed, fully open, and 3 4 open. Corrections are compared to calculations using the classical method of images.
Single photon scatter compensation by photopeak energy distribution analysis

Scattered photons degrade nuclear medicine image contrast and resolution, and preclude simple attenuation corrections. Current scatter correction methods utilize detected events with energies below pulse height analyzer (PHA) window levels, making attenuation corrections source position dependent. This new scatter rejection technique analyzes only the photon signals occurring within the range of standard PHA windows. In real time, at each image location the PHA window energy distribution is analyzed, a scatter fraction determined, and a scatter corrected number of events are output. The method can be adapted to any imaging system which produces event location and energy signals. Attenuation corrections (u=0.15 cm/sup -1/, 140 keV) are within 6% for 2-10 cm depths. >
Improved left-corner chart parsing for large context-free grammars

We develop an improved form of left-corner chart parsing for large context-free grammars, introducing improvements that result in significant speed-ups compared to previously-known variants of left-corner parsing. We also compare our method to several other major parsing approaches, and find that our improved left-comer parsing method outperforms each of these across a range of grammars. In addition, we describe a new technique for minimizing the extra information needed to efficiently recover parses from the data structures built in the course of parsing.
Equipartition of energy in geometric scattering theory

In this note, we use an elementary argument to show that the existence and unitarity of radiation fields implies asymptotic partition of energy for the corresponding wave equation. This argument establishes the equipartition of energy for the wave equation on scattering manifolds, asymptotically hyperbolic manifolds, asymptotically complex hyperbolic manifolds, and the Schwarzschild spacetime. It also establishes equipartition of energy for the energy-critical semilinear wave equation on ℝ3.