cssi/SciSciGPT-SciSciNet huggingface dataset:
Defensive agents of the American water beetles Agabus seriatus and Graphoderus liberus

Abstract Electrical shocking and rapid temperature reduction induced the dytiscid beetles Agabus seriatus and Graphoderus liberus to excrete pygidial and prothoracic defensive substances. When minnows ( Pimephales promelas ) were introduced into aqueous solutions of the defensive excretions from either beetle, they were rapidly inactivated and killed. The active agent was extractable in chloroform and constituted the major lipid component of the prothoracic defensive excretions. By means of thin-layer and gas-liquid chromatography, and ultraviolet and mass spectrometry, the biologically active material from the prothoracic defensive glands of both beetles was identified as a single steroid 11-deoxycorticosterone (DOC). The sensitivity of P. promelas to low levels of DOC made possible the development of a quantitative bioassay for this steroid in the defensive excretions. Quantitation by u.v. absorption at 240 nm and by the Pimephales bioassay showed A. seriatus contained ca. 40 μg DOC per beetle and G. liberus contained ca. 20 μg DOC per beetle. The major lipid component of the pygidial excretions of both beetles, p -hydroxybenzaldehyde, exhibited no toxic effect against test fish.
Errata-Economical Scheme for Estimating Orbital Lifetimes

1.00 Discussion As an example, the results for the particularly interesting nozzle throat (Y=l) are presented. In Fig. 2, C is plotted as a function of S with R as a parameter for m = 1. It can be seen that for growing S the correction factor C deviates increasingly from the limiting case C= 1. For expansion nozzles of rocket engines, \ 0.5 have been discussed. The dashed line for R — oo as a limiting case provides the correction factor for a tube. Figure 3 shows correction factor C as a function of m for different values of R for 7= 1 and 5 = 0.05. This shows that frequently a correction of Eq. (4) becomes indispensable because the error reaches a percentage that cannot be tolerated even in approximate calculation.
Time‐varying zonal asymmetries in stratospheric nitrous oxide and methane

Previously analyses of Stratospheric And Mesospheric Sounder (SAMS) data of atmospheric constituent gases have dealt almost exclusively with zonal means (and mostly monthly means), owing perhaps to concern over data quality. The purpose of this note is to show that, with care, time-dependent zonally-asymmetric features may be recovered from the SAMS nitrous oxide and methane data. As an example, we demonstrate the existence of zonal wave-1 constituent perturbations with periods of a few weeks in the middle and upper stratosphere. When the perturbations are normalized by the constituent zonal-mean mixing ratio to compensate for the slowly varying (in both space and time) background concentration of constituents, wavepacket-like features are found over all latitudes and seasons in the three-year SAMS record. One specific low-latitude case discussed had features which appear to be consistent with constituent oscillations induced by episodic equatorial Kelvin waves. Further studies are needed to better identify the nature of the plethora of observed wave-like phenomena.
Effects of adrenalectomy on thyroid function and insulin levels in obese (ob/ob) mice.

SummaryThe effects of adrenalectomy on the obese mouse were compared using animals which were weight-matched by controlled food intake. Adrenalectomy reduces weight gain of obese (ob/ob) mice. The reduced insulin and glucose after adrenalectomy are largely the result of reduced food intake. Changes in thyroid function are related to both the changes in food intake and to adrenalectomy itself.
Measurements of incoherent light and background structure at exo-Earth detection levels in the High Contrast Imaging Testbed

A major component of the estimation and correction of starlight at very high contrasts is the creation of a dark hole: a region in the vicinity of the core of the stellar point spread function (PSF) where speckles in the PSF wings have been greatly attenuated, up to a factor of 10 10 for the imaging of terrestrial exoplanets. At these very high contrasts, removing these speckles requires distinguishing between light from the stellar PSF scattered by instrument imperfections, which may be partially corrected across a broad band using deformable mirrors in the system, from light from other sources which generally may not. These other sources may be external or internal to the instrument (e.g. planets, exozodiacal light), but in either case, their distinguishing characteristic is their inability to interfere coherently with the PSF. In the following we discuss the estimation, structure, and expected origin of this incoherent" signal, primarily in the context of a series of experiments made with a linear band-limited mask in Jan-Mar 2013. We find that the incoherent" signal at moderate contrasts is largely estimation error of the coherent signal, while at very high contrasts it represents a true floor which is stable over week-timescales.
Some reliability properties of order statistics

Let Xi:j denote the ith order statistic of a random sample of size j from a continuous life distribution. We show that if Xk:n, is IFR, IFRA, NBU, or DMRL, so are Xk+1:n, Xk+1:n−1 and Xk+1:n+1. Further we show that, in the first three cases, Xk+1:n+2 also shares the corresponding property if k ≤ (n+3)/2. We also present dual results for DFR, DFRA and NWU classes.
Sliding mode control design of current fed full bridge DC to DC converter for fuel cell applications

Since a fuel cell system has a low voltage output, it requires a boost DC/DC converter for the most of vehicle and stationary power applications. In this paper, a robust sliding mode controller for the current fed full bridge DC/DC converter for PEM fuel cell systems is presented. The details of the sliding mode controller for the converter are derived and designed with a dynamic PEMFC model. The proposed sliding mode controller for converter with the PEMFC model is tested through Matlab/Simulink simulation. The results show the robust dynamics of the sliding mode controller with respect to load changes and the fuel cell voltage variation.
Did state regulation of power plants cause an increase in pollution exportation

Abstract The 1970 Clean Air Act divided responsibility for achievement of air quality standards between the EPA and states. It is widely believed that, as a result, state-regulated sources received taller stacks, but analysis suggests that this is not true.
Transport and detoxification systems for transition metals, heavy metals and metalloids in eukaryotic and prokaryotic microbes

Transition metals, heavy metals and metalloids are usually toxic in excess, but a number of transition metals are essential trace elements. In all cells there are mechanisms for metal ion homeostasis that frequently involve a balance between uptake and efflux systems. This review will briefly describe ATP-coupled resistance pumps. ZntA and CadA are bacterial P-type ATPases that confers resistance to Zn(II), Cd(II) and Pb(II). Homologous copper pumps include the Menkes and Wilson disease proteins and CopA, an Escherichia coli pump that confers resistance to Cu(I). For resistance to arsenicals and antimonials there are several different families of transporters. In E. coli the ArsAB ATPase is a novel system that confers resistance to As(III) and Sb(III). Eukaryotic arsenic resistance transporters include Acr3p and Ycf1p of Saccharomyces cerevisiae. These systems provide resistance to arsenite [As(III)]. Arsenate [As(V)] detoxification involves reduction of As(V) to As(III), a process catalyzed by arsenate reductase enzymes. There are three families of arsenate reductases, two found in bacterial systems and a third identified in S. cerevisiae.
Memory management units for microcomputer operating systems

Recently, independent memory management units for microprocessor based systems have become available. This note summarizes the features of register and tree memory management units (using MC68451 & MC68851 as examples) from a viewpoint of microcomputer operating systems design.
Small Signals, Large Signals, and Saturation in Generator Modeling

Test and analytic results from recent EPRI-sponsored programs are organized to explain insights into generator modeling. It is shown how small-signal tests and analysis are related to the nonlinear incremental properties of rotor iron. Changes in rotor circuit topology caused by rotation are identified. The large-signal response of rotor circuits is differentiated from the small-signal response. These effects, customarily lumped under the term ``saturation,'' are separated and differentiated.
The academic surgeon and industry.

Abstract Academic surgeons should be aware of the tremendous potential that exists to partner with private companies on projects relating either to basic or clinical research. This is particularly timely now because many of these companies are experiencing unprecedented growth and market valuation. The development of these relationships requires knowing who to deal with as well as how to negotiate. Most academic medical centers have individuals who have expertise in developing sponsored research agreements, and young investigators should take advantage of this expertise. (J Thorac Cardiovasc Surg 2000;119:S29-32)
Theory and renormalization of the gauge-invariant effective action

The different methods for constructing a gauge-invariant effective action (GIEA) for quantum non-Abelian gauge field theories proposed by 't Hooft, DeWitt, Boulware, and Abbott are all shown to be equivalent. In the course of proving this equivalence we show how to extend the usual background-field method so as to construct what may be considered the prototypical GIEA and discuss in some detail the invariance and gauge transformation properties of both the usual theory and the new theory using the GIEA. All solutions to the GIEA field equations are shown to be physical\char22{}being solutions to the usual field equations with an arbitrary gauge condition. The renormalization program based upon the GIEA is shown to differ from the standard theory and we outline the modifications which are needed in the present proof of renormalizability. In particular we prove that the physical renormalization is independent of any gauge-fixing choice. Finally, we prove that the $S$-matrix elements derived from the GIEA for an arbitrary background-field solution to the field equations are the same as those derived using the usual effective action.
Evaluation of the DotMap algorithm for locating analytes of interest based on mass spectral similarity in data collected using comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry

Abstract Comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC × GC–TOF-MS) is a highly selective technique ideal for the analysis of complex mixtures. The instrument yields an abundance of data, with complete mass spectral scans at every time point in the GC × GC separation space. The development and application of appropriate tools for data mining is essential in making sense of the wealth of information available. An algorithm for locating analytes of interest based on mass spectral similarity in GC × GC–TOF-MS data, called DotMap, has been previously reported and is rigorously evaluated herein. A thorough investigation into the performance characteristics of DotMap, including the performance near the limit of detection and dynamic range of the algorithm as well as the capacity of the algorithm to deal with peak overlap, is investigated using jet fuel as a complex sample matrix. For instance, the algorithm can successfully identify a spiked compound at the single μg/ml level in a jet fuel sample with an overlapping interferent. The performance of the DotMap algorithm in situations with very limited mass spectral selectivity, specifically in the evaluation of spectra from isomer compounds, as well as the ability to tune DotMap results to provide the location of a specific analyte or of a class of compounds is demonstrated. The DotMap algorithm is demonstrated to be a sensitive tool that is useful in the analysis of complex mixtures and which possesses the capacity to be easily “tuned” to discern the location of analytes of interest.
Predictive Modeling of Large-Scale Integrated Refinery Reaction and Fractionation Systems from Plant Data. Part 3: Continuous Catalyst Regeneration (CCR) Reforming Process

This work presents a model for the rating and optimization of an integrated catalytic reforming process with UOP-style continuous catalyst regeneration (CCR) using Aspen HYSYS/Petroleum Refining. The model relies on routinely monitored data, such as American Society for Testing and Materials (ASTM) distillation curves, paraffin–napthene–aromatic (PNA) analysis, and operating conditions. We use a lumped kinetic network with 64 species over a broad C1–C14 range. This network can represent the key dehydrogenation, dehydrocyclization, isomerization, and hydrocracking reactions that typically occur with petroleum feedstock. The lumped kinetic scheme also allows us to make accurate predictions of benzene, toluene, ethylbenzene, and xylenes (BTEX). In addition, this work accounts for the coke deposited on the catalyst and the associated catalyst regeneration. We implement the hydrogen recycle and product recontacting sections as separate unit operations connected to the CCR reformer model. In addition, we includ...
Dicephalus dipus dibrachius: An unusual case of conjoined twins

Conjoined twinning is a rare anomaly, occurring in one of every 50,000 births. Dicephalus dipus dibrachius is an extremely rare form of conjoined twinning in which the infant has two arms, two legs, one trunk, but two heads. These infants are often stillborn or die shortly after birth. The authors describe a case of dicephalus twinning with 11-day survival. A thorough investigation using multiple imaging modalities (plain radiographs, contrast studies, ultrasonography, and magnetic resonance imaging) demonstrated that these twins had separate spinal columns but shared multiple internal organs including heart, liver, pancreas, intestine and bladder. Based on the anatomy of this case, the authors conclude that separation of dicephalus dipus dibrachius twins should not be attempted.
An Exploration of Transport Within Microdroplet and Nanodroplet Clusters During Dropwise Condensation of Water on Nanostructured Surfaces

Experimental studies of dropwise condensation have generally indicated that higher heat transfer coefficients correspond to smaller mean sizes for droplets growing through condensation on the surface. Recent investigations of dropwise condensation on nanostructured surfaces suggest that optimizing the design of such surfaces can push mean droplet sizes down to smaller values and significantly enhance heat transfer. This paper summarizes a theoretical exploration of the limits of heat transfer enhancement that can be achieved by pushing mean droplet size to progressively smaller sizes. A model analysis is developed that predicts transport near clusters of water droplets undergoing dropwise condensation. The model accounts for interfacial tension effects on thermodynamic equilibrium and noncontinuum transport effects, which become increasingly important as droplet size becomes progressively smaller. In this investigation, the variation of condensing heat transfer coefficient for droplet clusters of different sizes was explored for droplet diameters ranging from hundreds of microns to tens of nanometers. The model predictions indicate that the larger droplet transport trend of increasing heat transfer coefficient with decreasing mean droplet size breaks down as droplet size becomes smaller. The model further predicts that as drop size becomes smaller, a peak heat transfer coefficient is reached, beyond which the coefficient drops as the size continues to diminish. This maximum heat transfer coefficient results from the increasing importance of surface tension effects and noncontinuum effects as droplet size becomes smaller. The impact of these predictions on the interpretation of dropwise condensation heat transfer data, and the implications for design of nanostructured surfaces to enhance dropwise condensation are discussed in detail.
Effect of thyroid hormone on hepatic cholesterol 7α hydroxylase, LDL receptor, HMG-CoA reductase, farnesyl pyrophosphate synthetase and apolipoprotein A-I mRNA levels in hypophysectomized rats

The effects of thyroid hormone on cholesterol 7 alpha hydroxylase, LDL receptor, HMG-CoA reductase, apo A-I and farnesyl pyrophosphate synthetase hepatic mRNA levels were investigated in hypophysectomized rats. Of these mRNAs cholesterol 7 alpha hydroxylase responded the most rapidly and required the lowest dose of T3. Maximal mRNA levels were reached one hr after T3 administration and required 10 micrograms/100g of body weight. These results suggest that the hypocholesterolemic effect of thyroid hormone may be mediated by a primary effect on cholesterol 7 alpha hydroxylase gene expression.
Motion planning using navigation measure

Navigation measure is introduced as a new tool to solve the motion planning problem in the presence of static obstacles. Existence of the navigation measure guarantees collision free convergence to the final destination set. Navigation measure can be viewed as a dual to the navigation function, a popular tool used in the motion planning literature today. While navigation function has its minimum at the final destination set and peaks at the obstacle sets, the navigation measure on the other hand takes maximum value at the destination set and is zero on the obstacle set. A linear programming formalism is proposed for the construction of navigation measure. Set oriented numerical methods are used to obtain finite dimensional approximation of the navigation measure.
Regulation of gene expression during swarmer cell differentiation in Proteus mirabilis

The gram-negative bacterium Proteus mirabilis can exist in either of two cell types, a vegetative cell characterized as a short rod and a highly elongated and hyperflagellated swarmer cell. This differentiation is triggered by growth on solid surfaces and multiple inputs are sensed by the cell to initiate the differentiation process. These include the inhibition of flagellar rotation, the accumulation of extracellular putrescine and O-antigen interactions with a surface. A key event in the differentiation process is the upregulation of FlhD2C2, which activates the flagellar regulon and additional genes required for differentiation. There are a number of genes that influence FlhD2C2 expression and the function of these genes, if known, will be discussed in this review. Additional genes that have been shown to regulate gene expression during swarming will also be reviewed. Although P. mirabilis represents an excellent system to study microbial differentiation, it is largely understudied relative to other systems. Therefore, this review will also discuss some of the unanswered questions that are central to understanding this process in P. mirabilis .
MOLE: a knowledge acquisition tool that uses its head

MOLE can help domain experts build a heuristic classification problem-solver by working with them to generate an initial knowledge base and then detect and remedy deficiencies in it. By exploiting several heuristic assumptions about the world, MOLE is able to minimize the information it needs to elicit from the domain expert. In particular, by using static techniques of analysis, MOLE is able to infer support values and fill in gaps when a knowledge base is under-specified. And by using dynamic techniques of analysis, MOLE is able to interactively refine the knowledge base.
Dynamics of pulsing flow in trickle beds

A macroscopic model of two-phase flow in packed beds, based on the volume-averaged equations of motion for the gas and liquid phases, was analyzed in an attempt to understand the onset and evolution of fully-developed pulsing flow in trickle beds. By assuming that solutions take the form of waves travelling at constant speed, periodic solutions to these equations are found which can be associated with long-time, asymptotic behavior of pulses in a very long bed. Families of one-dimensional waves which exist at a particular set of mass fluxes can be characterized by infinite period bifurcations in the travelling wave frame. We numerically follow these bifurcations as the fluxes are changed, generating bifurcation diagrams for the original model. The results predict that properties of one-dimensional pulses should correlate with the total superficial velocity through the bed. A hysteresis in the trickling-pulsing transition is also predicted.
Risk factor assessment for the development of osteoradionecrosis.

Purpose Osteoradionecrosis (ORN) of the jaws has been extensively studied. However, controversy still exists regarding its etiology, risk factors, and the underlying mechanism of disease. The purpose of this study was to identify and evaluate significant risk factors for the development of ORN. Patients and Methods This was a retrospective cohort study of 82 Massachusetts General Hospital patients radiated for head and neck cancer between 1984 and 2005. Patient records were reviewed to collect demographic information, medical and dental history (including dental intervention or trauma), tumor specific data, treatment details, and follow-up. Biologic variables (ie, age and gender) of potential significance were also evaluated. The major outcome variable was the development of ORN or lack of development of ORN. The time from radiation to ORN, or for non-ORN patients, time to last follow-up visit, was computed. Univariate analyses identified candidate variables associated with ORN (P Results Multivariate regression identified the following variables as significantly associated with decreased ORN risk: higher body mass index (P = .02) and use of steroids (P = .02). Radiation dose greater than 66 Gray (P = .03) was associated with an increased ORN risk. Conclusions Optimization of nutritional status, use of steroids, and limitation of total radiation dose may minimize the risk of ORN.
Unlocking Information Technology

Computer technology has made vast quantities of information more readily available through accessible data bases. This article discusses the use of information technology and some of the problems that have prevented it from being more widely used. Also included is information on some rehabilitation-related data bases.
Lower forest-grassland ecotones and 20th Century livestock herbivory effects in northern Mongolia

Westudied fivelower forest‐grassland ecotones inthe Darhad Valleyin northern Mongolia andinvestigated the effects of20th Century grazing regimes and changes in grazing management on ecotone dynamics at a local scale. A total of 2968 Siberian larch (Larix sibirica) trees were cored and tree-age distribution was constructed to determine 20th Century tree establishment. Tree age and location within the ecotones were correlated and seedling density and their distribution were explored to describe forest‐grassland ecotone shift. To examine livestock herbivory effects on ecotone shift, the number of new trees was analyzed with fivedifferent grazing regimes and changes in grazing practices during the last 80 years in the Darhad Valley. We documented some evidence of ecotone shift into the adjacent grassland. Rates and patterns of ecotone shift varied with different grazing regimes. Siberian larch tree establishment was greater at overall grazing intensities of low and high levels, which were dominated by sheep and cattle grazing. In contrast, larch establishment was lower at overall grazing intensities of low and medium levels, which were dominated by goat grazing. Twentieth Century changes in grazing practices also influenced Siberian larch regeneration. An abrupt decline in Darhad Valley larch establishment during the 20th Century coincided with locally increased grazing pressure. Furthermore, regional climate variability showed important interaction with local grazing regimes in affecting larch regeneration. A 20th Century pulse in larch establishment coincided with a time period of regionally known warmer temperatures and locally reduced grazing pressure. Our results suggest that overall grazing intensity, livestock species composition, and changes in grazing patterns are important in understanding grazing effects on Siberian larch tree encroachment. # 2006 Elsevier B.V. All rights reserved.
Boosting Item Keyword Search with Spreading Activation

Most keyword search engines return directly matching keyword phrases. However, publishers cannot anticipate all possible ways in which users would search for the items in their documents. In fact, many times, there may be no direct keyword match between a keyword search phrase and descriptions of relevant items that are perfect matches for the search. We present an automated, high precision-based information retrieval solution to boost item find-ability by bridging the semantic gap between item information and popular keyword search phrases. Our solution achieves an average of 80% F-measure for various boosted matches for keyword search phrases in various categories.
On the Coupling Between Adjacent Turbulent Jets

A detailed examination of the coupling observed between adjacent turbulent jets, one of which was externally excited, is presented. The study is relevant to the active control of combustion and mixing devices; applications which demand maximum reliability and minimal power consumption by their active elements. To this end, it is desirable for each active component to affect several simple, non-active components in the system. An initial study of three collinear turbulent air jets was seen to enhance the mixing of adjacent, unforced jets with ambient fluid by 15–20%. The work presented here examines this phenomena using quantitative PLIF mixing measurements, three component and single-wire velocity measurements, qualitative flow visualization, and reduced singular value decomposition (SVD). This analysis of the data shows that the mixing improvement in the adjacent, unforced jets is primarily due to the low level perturbation at the exit of the unforced jets induced by the periodic forcing in the active center jet. This improved mixing is shown to be a result of amplification of the +/-1 spatial mode. Large scale structures in the central, forced jet are shown not to effect the behavior of the adjacent jets.Copyright © 2002 by ASME
Cognitive effects of racial diversity: White individuals' information processing in heterogeneous groups.

Two experiments tested the hypothesis that mere anticipation of membership in a racially heterogeneous group can lead White individuals to exhibit more thorough information processing. In Study 1 White participants who expected to discuss a race-relevant topic with a racially diverse group exhibited better comprehension of topical background readings than did Whites assigned to all-White groups. Study 2 replicated these results and indicated that the processing effects were attributable in part to an increase in race-relevant thought activation among White individuals in a diverse setting. No such anticipatory effects of racial composition were observed for Whites expecting to discuss race-neutral topics. Taken together, these studies render untenable the assumption that the observable effects of racial diversity are wholly attributable to the novel contributions of non-White group members. More generally, they emphasize the need for additional empirical investigation of the cognitive processes through which racial heterogeneity influences individual and group performance.
Using adaptive hypermedia to support organizational memory and learning

The skills, knowledge and abilities of today's workforce require continuous improvement. As a knowledge-based global economy evolves, organizations must strive to optimize human and intellectual capital. This paper examines some aspects of intelligent organizations. In particular, it explores the use of information technology to support memory, knowledge and learning in organizations. An adaptive hypermedia system is described which incorporates hypertext navigation, information filtering and multimedia artifacts to provide high-level query and browsing capabilities for information repositories. Design issues for such a system are discussed along with limitations imposed by current technological constraints. The system would include tools to dynamically store and retrieve organizational memory electronically. Such a system would provide mechanisms to access information context in which to understand past and present events, and a mechanism to bring a multitude of lessons and experiences to bear on present and future activities.
Nonlinear-least-squares analysis of slow-motion EPR spectra in one and two dimensions using a modified levenberg-marquardt algorithm

Abstract The application of the “model trust region” modification of the Levenberg–Marquardt minimization algorithm to the analysis of one-dimensional CW EPR and multidimensional Fourier-transform (FT) EPR spectra especially in the slow-motion regime is described. The dynamic parameters describing the slow motion are obtained from least-squares fitting of model calculations based on the stochastic Liouville equation (SLE) to experimental spectra. The trust-region approach is inherently more efficient than the standard Levenberg–Marquardt algorithm, and the efficiency of the procedure may be further increased by a separation-of-variables method in which a subset of fitting parameters is independently minimized at each iteration, thus reducing the number of parameters to be fitted by nonlinear least squares. A particularly useful application of this method occurs in the fitting of multicomponent spectra, for which it is possible to obtain the relative population of each component by the separation-of-variables method. These advantages, combined with recent improvements in the computational methods used to solve the SLE, have led to an order-of-magnitude reduction in computing time, and have made it possible to carry out interactive, real-time fitting on a laboratory workstation with a graphical interface. Examples of fits to experimental data will be given, including multicomponent CW EPR spectra as well as two- and three-dimensional FT EPR spectra. Emphasis is placed on the analytic information available from the partial derivatives utilized in the algorithm, and how it may be used to estimate the condition and uniqueness of the fit, as well as to estimate confidence limits for the parameters in certain cases.
Total synthesis of (+/-)-strychnine via a [4 + 2]-cycloaddition/rearrangement cascade.

A new strategy for the synthesis of the Strychnos alkaloid (±)-strychnine has been developed and is based on an intramolecular [4 + 2]-cycloaddition/rearrangement cascade of an indolyl-substituted amidofuran. The critical D-ring was assembled by an intramolecular palladium-catalyzed enolate-driven cross-coupling of an N-tethered vinyl iodide.
Generalized matrix inverse reconstruction for SPECT using a weighted singular value spectrum

A method of weighting the singular value spectrum for SPECT image reconstruction with generalized matrix inverses (GMIs) has been developed, for the purpose of obtaining more localized source activity estimates than can be obtained with the use of a truncated spectrum. At each source voxel, spectral weights are computed to minimize the misfit of the resolution kernel with an ideal unit response (discretized delta function), subject to a constraint on the variance of the reconstructed source activity. This method was applied to a Monte Carlo simulated Tc-99m myocardial perfusion study and a Tc-99m myocardial perfusion phantom study acquired on a clinical scanner. GMI reconstructions using weighted and truncated spectra were compared. Resolution kernels for a weighted spectrum are narrower and have smaller sidelobes than kernels for a truncated spectrum. As a result, with the use of a weighted spectrum the resolution of reconstructed SPECT images is improved, the simulated myocardial wall thickness is better estimated and reconstructed activity is smoother in regions of uniform activity. The use of a weighted singular value spectrum is an important tool for obtaining more localized source activity estimates with GMI reconstruction.
Reliability Assessment of FRP-Strengthened Concrete Bridge Girders in Shear

AbstractThis paper presents the results from an investigation into the reliability of reinforced concrete bridge girders strengthened in shear using fiber-reinforced polymers (FRP). Two expressions for the shear design of FRP-strengthened girders were developed as part of a National Cooperative Highway Research Program project. The expressions were developed for two distinct cases, namely, bonded and anchored FRP reinforcement. Uncertainties inherent in the new design models were first assessed using an extensive database of hundreds of experimentally tested specimens. Variabilities in material, fabrication tolerances, dead and live loads, and distribution factors obtained from the literature were then included in a limit state function for the shear strength mode of failure. The reliability of a representative design space comprising 18 bridge girders that cover different span lengths, shear deficiency levels, and girder location (exterior versus interior) was calculated for both bonded and anchored stre...
New concepts on the immune modulation mediated by mesenchymal stem cells

Mesenchymal stem cells (MSCs) are the nonhematopoietic multipotent progenitor cells found in various adult tissues. They are characterized by their ease of isolation and their rapid growth in vitro while maintaining their differentiation potential, allowing for extensive expansion in culture that yields large quantities suitable for therapeutic use. This article reviews the immunomodulatory activities associated with MSCs. Numerous studies have demonstrated that MSCs are potently immunosuppressive in vitro and in vivo. However, this article presents a new paradigm in MSC biology, in which MSCs, at least in vitro, can undergo polarization into either a pro-inflammatory or an immunosuppressive phenotype.
A discrete-time method of demodulating large deviation FM signals

A method of enhancing the performance of a numerical FM discriminator in specific receive signal conditions, using frequency feedback techniques, is developed and evaluated. The receive signal conditions of interest are: (1) frequency deviations that are large relative to the bandwidth of the message signal; (2) a low-uniform (complex) sample rate commensurate with the bandwidth; and (3) noise strengths that yield values of input carrier-to-noise ratio of the order of 10 dB or more. Through computer simulation, observed phase cycle-slip counts and phase noise variance estimation are used to compare the enhanced demodulator to the performance of a numerical FM discriminator baseline. Based upon the theoretical analyses and simulation results, the presented method of numerical FM demodulation is shown to be a viable technique for enhancing the performance of numerical FM discriminators under the given modulation conditions.
Great spotted woodpeckers Dendrocopos major exert multiple forms of phenotypic selection on Scots pine Pinus sylvestris

Relatively few animal species extract seeds from closed conifer cones because of the forces required to spread apart or penetrate the woody scales. Those species that forage on seeds in closed cones tend to forage selectively, and therefore act as selective agents on cone structure. However, little is known about the foraging preferences and thus phenotypic selection that is exerted on conifers by many species that forage extensively on seeds in closed cones, including especially woodpeckers (Picidae). Great spotted woodpeckers Dendrocopos major are one of the main predators of seeds in closed cones of Scots pine Pinus sylvestris in central and eastern Europe. To estimate the cone preferences of these woodpeckers foraging on Scots pine, we contrasted traits of cones that were and were not foraged on by woodpeckers. Woodpeckers preferred to forage on shorter cones when scales were thin (smaller apophyses) but preferred cones of intermediate length when scales were thicker, providing evidence for correlational selection. The preference for intermediate-sized cones indicates that woodpeckers exert disruptive selection on cone length when cones have thicker scales, but the overall selection on cone length across all scale types indicates directional favoring the evolution of longer cones. Woodpeckers avoided cones with thicker scales, which would lead to directional selection favoring the evolution of thicker scales. Preferences for intermediate-sized cones have been found in tree squirrels and directional selection favoring the evolution of cones with thicker scales may be a common outcome of the foraging behavior of birds.
The Impact of Aging Effects and Manufacturing Variation on SRAM Soft-Error Rate

This paper describes modeling and hardware results of how the soft-error rate (SER) of a 65-nm silicon-on-insulator SRAM memory cell changes over time, as semiconductor aging effects shift the SRAM cell behavior. This paper also describes how the SER changes in the presence of systematic and random manufacturing variation.
Binding of Prostaglandin F2α to Membranes of Shell Gland Muscle of Laying Hens: Correlations with Contractile Activity

Specific binding of prostaglandin F2a (PGF20) to a membrane fraction prepared from the shell gland muscle of laying hens was characterized as a concentration dependent, irreversible (at 0_C or 20#{176}C) or partially reversible (at 37#{176}C) interaction with a limited number of binding sites (about 1 pmol/mg protein). The 9 and 11 hydroxyl groups, the 5 (cis) double bond and the a steric position of the heptanoic acid side chain of the PGF20 molecule appear to be essential prerequisites for optimal binding. Properties of this binding reaction were compared to the characteristics of in vitro contractile responses of shell gland strips to PGF20. The results indicate that 1) both specific binding and contractile responses can be elicited with physiological concentrations of PGF30, 2) the binding of PGF2a and the contractile response of the shell gland muscle are both very rapid processes which attain a maximum value within 1 mm, 3) both the saturation of the membranes and the maximal contractile response are achieved at 2 X 106 M PGF20. However, half maximal binding can be demonstrated at 4 X 10’ M, whereas half maximal response at 2 X 10� M PGF2a, 4) both the binding affinity to PGF2a binding sites and the contraction stimulating activity of PGE, is substantially lower than those of PGF2 �
Why are Profits from Financial Innovation So Difficult to Identify? Innovation Clusters and Productive Opacity

The empirical literature identifying gains from financial innovation to financial institution stockholders is sparse. The literature identifying financial firms' contributions to stockholder value resulting from long term commitment to innovation is, to our knowledge, nonexistent. Several authors note that the protection of financial engineering innovations from imitation is particularly challenging. We consider the implications for the structure of financial innovation, proposing a stylized representation of the innovative process called "the cluster hypothesis." Under the hypothesis, innovations occur in symbiotic collections of transparent "external innovations," together with opaque "internal innovations." Only the latter provide economic rents. We find evidence that innovation-induced opacity drives long run relative rewards at added risk for financial institution stockholders.
An Overview of Language Policies in African Literature

This paper is an overview of some important questions on African Literature. In fact, over the past few decades, a lot of questions have been raised on African Literature. Among those questions is posed the question of the existence or absence of an African Literature proper. Two schools of thought have led the debates on this matter. The first school thought that claims the existence of an African Literature written on Africa and priortitizes the use of African languages to write African Literature, while the second school of thought tends to give a wide dimension of an African literature written in any language possible. It could be the language of the colonizer or any other African language that can represents the Identity of Africans as a whole. I therefore dedicate this paper as an attempt to help grasp these questions around the African Literature.
String diagrams for traced and compact categories are oriented 1-cobordisms

Abstract We give an alternate conception of string diagrams as labeled 1-dimensional oriented cobordisms, the operad of which we denote by Cob / O , where O is the set of string labels. The axioms of traced (symmetric monoidal) categories are fully encoded by Cob / O in the sense that there is an equivalence between Cob / O -algebras, for varying O , and traced categories with varying object set. The same holds for compact (closed) categories, the difference being in terms of variance in O . As a consequence of our main theorem, we give a characterization of the 2-category of traced categories solely in terms of those of monoidal and compact categories, without any reference to the usual structures or axioms of traced categories. In an appendix we offer a complete proof of the well-known relationship between the 2-category of monoidal categories with strong monoidal functors and the 2-category of monoidal categories whose object set is free with strict functors; similarly for traced and compact categories.
Protocol for Uniformly Measuring and Expressing the Performance of Energy Storage Systems

The U.S. Department of Energy's Energy Storage Systems (ESS) Program, through the support of Pacific Northwest National Laboratory (PNNL) and Sandia National Laboratories (SNL), facilitated the development of the protocol provided in this report. The focus of the protocol is to provide a uniform way of measuring, quantifying, and reporting the performance of ESSs in various applications; something that does not exist today and, as such, is hampering the consideration and use of this technology in the market. The availability of an application-specific protocol for use in measuring and expressing performance-related metrics of ESSs will allow technology developers, power-grid operators and other end-users to evaluate the performance of energy storage technologies on a uniform and comparable basis. This will help differentiate technologies and products for specific application(s) and provide transparency in how performance is measured. It also will assist utilities and other consumers of ESSs to make more informed decisions as they consider the potential application and use of ESSs, as well as form the basis for documentation that might be required to justify utility investment in such technologies.
Predicting the occurrence of mixed mode failure associated with hydraulic fracturing, part 2 water saturated tests

Seven water-saturated triaxial extension experiments were conducted on four sedimentary rocks. This experimental condition was hypothesized more representative of that existing for downhole hydrofracture and thus it may improve our understanding of the phenomena. In all tests the pore pressure was 10 MPa and confirming pressure was adjusted to achieve tensile and transitional failure mode conditions. Using previous work in this LDRD for comparison, the law of effective stress is demonstrated in extension using this sample geometry. In three of the four lithologies, no apparent chemo-mechanical effect of water is apparent, and in the fourth lithology test results indicate some chemo-mechanical effect of water.
Renormings concerning exposed points and non-smoothness

Intuitively, non-smooth points might look like exposed points. However, in this paper we show that real Banach spaces having dimension greater than or equal to three can be equivalently renormed to obtain non-smooth points which are also non-exposed.
Grasp detection for assistive robotic manipulation

In this paper, we present a novel grasp detection algorithm targeted towards assistive robotic manipulation systems. We consider the problem of detecting robotic grasps using only the raw point cloud depth data of a scene containing unknown objects, and apply a geometric approach that categorizes objects into geometric shape primitives based on an analysis of local surface properties. Grasps are detected without a priori models, and the approach can generalize to any number of novel objects that fall within the shape primitive categories. Our approach generates multiple candidate object grasps, which moreover are semantically meaningful and similar to what a human would generate when teleoperating the robot—and thus should be suitable manipulation goals for assistive robotic systems. An evaluation of our algorithm on 30 household objects includes a pilot user study, confirms the robustness of the detected grasps and was conducted in real-world experiments using an assistive robotic arm.
Quality Control Procedures for Newer Radiopharmaceuticals

This is the fourth article in a four-part series on new radiopharmaceuticals. Upon completion of this article, the reader should be able to (1) recognize the need for assessment of radiochemical purity, (2) describe some of the available systems, and (3) be aware of common errors in performing quality control on the newer radiopharmaceuticals.
Is There an Association between Ocular Adnexal Lymphoma and Chlamydia psittaci Infection? The University of Rochester Experience.

Several subsets of extranodal marginal zone lymphomas of mucosa-associated lymphoid tissues (MALT lymphomas) have been associated with infectious organisms. This finding is of particular significance in the treatment of these conditions because it suggests that eliminating the source of the antigen may result in regression of the malignancy. For example, gastric MALT lymphoma is associated with Helicobacter pylori infection. Antibiotic therapy that eliminates the H. pylori infection frequently causes regression of the lymphoma. Ferreri et al (2004, J Natl Cancer Inst. 96:586) reported the presence of Chlamydia psittaci DNA in 80% of 40 ocular adnexal lymphomas. Consistent with the gastric MALT lymphoma data, a subset of these patients responded well to antibiotic treatment. We used a PCR based assay similar to that of Ferreri et al to analyze a set of ocular adnexal lymphomas and benign (non-neoplastic) lesions for evidence of C. psittaci DNA in patients from New York State. No evidence of C. psittaci DNA was seen in seven MALT-type ocular adnexal lymphomas, four non-MALT B-cell ocular adnexal lymphomas, one Langerhans histiocytosis, and five reactive lymphoproliferations. In addition, we found no evidence for C. psittaci in DNA samples from 21 monoclonal B-cell lymphomas from sites other than the ocular adnexa. We confirmed the negative results using an alternate PCR target in the 23S ribosomal RNA gene. In addition, we used appropriate controls to demonstrate that PCR inhibition and DNA template degradation did not affect our results. We conclude that C. psittaci infection did not play a role in the ocular adnexal lymphoproliferations in our survey. The difference in results with the previous report (Ferreri et al) suggests geographical differences in the incidence of C. psittaci infection, or other unknown disease cofactors.