cssi/SciSciGPT-SciSciNet huggingface dataset:
Oxygen adsorption and oxide formation on V(100) surfaces

The initial stages of the uptake of molecular oxygen on V(100) single-crystal surfaces were characterized by temperature programmed desorption (TPD), X-ray photoelectron spectroscopy (XPS), and ion scattering spectroscopy (ISS). As in previous reports on this system, a small amount of oxygen contamination was always detected on the surface, but that could be minimized by avoiding severe annealing after sputtering of the surface and appears to not affect the chemistry of the surface in any significant way, at least in terms of methanol conversion. Oxygen adsorption is dissociative even at liquid nitrogen temperatures. At low temperatures, saturation is reached at a coverage of approximately 1.0 ML, but above 170 K further uptake can occur, leading to the formation of a thin V2O3 + VO2 mixed oxide film. Thick oxide films, with thicknesses of the order of nanometers, could only be generated above 320 K and by using high oxygen doses. In general, the temperature at which the adsorption is carried out proved t...
A novel role of Rac1 GTPase in JCV T-antigen-mediated β -catenin stabilization

Wnt signaling follows canonical and non-canonical pathways to regulate a variety of processes during cellular homeostasis and development. The large T-antigen (T-Ag) of the human neurotropic JC virus, has been shown to modulate the Wnt-signaling pathway via interaction with β-catenin, one of the most important components of the canonical Wnt pathway. Here, we have identified an alternative non-canonical pathway that allows T-Ag to recruit Rac1 for stabilizing β-catenin by inhibiting its ubiquitin-dependent proteasomal degradation. We demonstrate that inhibition of Rac1 by its dominant negative mutant, RacN17, abrogates T-Ag-mediated stabilization of β-catenin yet exhibits no impact on the transcriptional activity of β-catenin. Results from immunocytochemistry revealed that together with T-Ag, a pool of β-catenin appears at the cell surface, particularly at the membrane ruffles where active Rac1 is positioned. Interestingly, cooperativity between T-Ag and β-catenin leads to activation of Rac1, which in turn, stimulates its association with β-catenin. These observations unravel the interplay between β-catenin and Rac1 that is initiated by T-Ag and results in stabilization of β-catenin and its presence in cell membrane ruffles.
Maximizing contrast resolution in the outer retina of mammals

The outer retina removes the first-order correlation, the background light level, and thus more efficiently transmits contrast. This removal is accomplished by negative feedback from horizontal cell to photoreceptors. However, the optimal feedback gain to maximize the contrast sensitivity and spatial resolution is not known. The objective of this study was to determine, from the known structure of the outer retina, the synaptic gains that optimize the response to spatial and temporal contrast within natural images. We modeled the outer retina as a continuous 2D extension of the discrete 1D model of Yagi et al. (Proc Int Joint Conf Neural Netw 1: 787–789, 1989). We determined the spatio-temporal impulse response of the model using small-signal analysis, assuming that the stimulus did not perturb the resting state of the feedback system. In order to maximize the efficiency of the feedback system, we derived the relationships between time constants, space constants, and synaptic gains that give the fastest temporal adaptation and the highest spatial resolution of the photoreceptor input to bipolar cells. We found that feedback which directly modulated photoreceptor calcium channel activation, as opposed to changing photoreceptor voltage, provides faster adaptation to light onset and higher spatial resolution. The optimal solution suggests that the feedback gain from horizontal cells to photoreceptors should be ∼0.5. The model can be extended to retinas that have two or more horizontal cell networks with different space constants. The theoretical predictions closely match experimental observations of outer retinal function.
Ontological categories and function: Acquisition of new names

Abstract This study asks whether knowledge of the functional properties of a referent for a new name influences children's first guesses about whether that name refers to an object or a substance. Recent work on children's categorization suggests that children differentiate concrete objects from nonsolid substances and that their initial hypotheses about the meanings of new words are affected by this knowledge of ontological categories. In addition, some research has suggested that children approach new words with a set of biases that constrain the possible meanings of those words. Most of this work has presented children with new names in the absence of explicit information about the functional characteristics of new referents. Our hypothesis was that if children are shown the functional properties of referents, they should use that information in making their first guesses about the meanings of new words. Seventy-two 3- and 4-year-olds were shown new items with new names and were tested on their extension of each new name either to a similarly shaped item made of a different material or to a differently shaped item made of the same material. Some subjects were shown a “shape-linked” function, some a “substance-linked” function, and some no function at all. One third of the subjects heard the new names presented with count syntax, one third with mass syntax, and one third with neutral syntax. Results suggest that children do not rely on a single source of information in extending new names, but, rather, draw on various kinds of information, including the perceptual characteristics of the entities themselves and the syntax of the input.
Video compression with flexible playback order based on distributed source coding

Some emerging applications may require flexible playback features for time-based media, such as video, that cannot be directly supported by current compression standards, because for these decoding of frames can only be done in a predetermined order. An example would be a video application where both backward and forward frame-by-frame playback are to be supported. A standard codec could support this by decoding complete GOPs in the desired order, and then playing back one frame at a time. Thus, potentially significant added delay and memory are needed to support backward playback, which can be lowered if small GOP sizes are chosen, at the cost of reduced coding efficiency. Other example applications where flexible playback may be desirable include switching between different views in multiview video coding, and accessing individual spectral bands in hyperspectral imagery. In this work we address flexible playback by showing that it becomes feasible when a particular data unit (e.g., a video frame) can be decoded using information from either one of a number of other data units (e.g., in the video case the next frame or the previous frame). Note that this is different from structures such as bi-directionally predicted frames, which require both predictor frames to be available at the decoder. We cast this problem as one of source coding with uncertainty about decoder side-information and propose a solution based on distributed source coding. In addition, we propose macroblock-based mode switching algorithms in the context of distributed video coding to improve coding efficiency. Our results show that, using forward/backward playback as an example, our proposed solution can achieve good coding efficiency without incurring additional delay and memory overhead.
General equilibrium and the theory of directed graphs

Abstract The classical Arrow-Debreu existence theorem for a general equilibrium requires an assumption of positive endowments of all commodities by all consumers. This paper presents new results for relaxing this assumption for a class of economic models in which utility functions and production possibility sets are limited to certain special but useful forms, including the commonly used Cobb-Douglas and constant elasticity of substitution (CES) forms. For a given model, a directed graph is constructed which relates the sources of commodities and profits to users of commodities and recipients of profits, and it is proved that the existence of a competitive equilibrium is related to the strong connectedness of the graph. This allows equilibrium existence testing for economic models of arbitrary size by efficient computational algorithms.
Classification of Spectral Patterns Obtained from Eustachian Tube Sonometry

Spectral patterns of sound transmission through the Eustachian tube (ET) have been obtained in a series of experiments designed to identify ET dysfunction. Previous studies of ET function using sonometry have relied on heuristic and somewhat arbitrary methods in interpreting the data. In this study, an automated classification algorithm was developed to separate these sonograms into three distinct groups. From a total of 150 sample spectra, 75 were used in the formation of learning sets. The remaining spectra were classified into these three groups using standard Bayesian techniques. Both parametric and nonparametric methods were applied in estimating conditional probability density functions. Results of classification are compared with an independent test of ET function. Agreement between our classifier and the results of the independent test was as good as 97.3 percent. The results of this study indicate that an automated classification procedure can effectively distinguish among the three major types of sonograms obtained from ET sonometry.
Axioms and theorems for a theory of arrays

Array theory combines APL with set theory, transfinite arithmetic, and operationally transformed functions to produce an axiomatic theory in which the theorems hold for all arrays having any finite number of axes of arbitrary countable ordinal lengths. The items of an array are again arrays. The treatment of ordinal numbers and letters is similar to Quine's treatment of individuals in set theory. The theory is developed first as a theory of lists. This paper relates the theory to the eight axioms of Zermelo-Fraenkel set theory, describes the structure of arrays, interprets empty arrays in terms of vector spaces, presents a system of axioms for certain properties of operations related to the APL function of reshaping, deduces a few hundred theorems and corollaries, develops an algebra for determining the behavior of operations applied to empty arrays, begins the axiomatic development of a replacement operator, and provides an informal account of unions, Cartesian products, Cartesian arrays, and outer, positional, separation, and reduction transforms.
'Normal'-pressure Hydrocephalus and the Saga of the Treatable Dementias

SELECTED CASE A 74-YEAR-OLD widow presented to the Laboratory of Neurosciences of the National Institute on Aging in February 1985 with a 4-year history of progressive cognitive impairment. She had experienced gradual onset of memory loss, with occasional urinary incontinence. There was no history of hypertension, cardiovascular disease, diabetes, head trauma, stroke, or intracranial bleeding or infection. She was not taking any medications. Social and family histories were not contributory. Findings from a general physical examination were normal. Neurological examination disclosed a mild dementia, with impaired memory, calculations, and constructions. Her score on the Mini-Mental State Examination 1 was 22 (23 to 30 is normal), and her score on the Blessed Memory and Information Concentration Test was 22 (normal score is 37). 2 She had poor balance but normal gait. Results from routine laboratory tests of blood and urine were normal, as was an electroencephalogram. Cerebrospinal fluid protein level, glucose
Solution‐Processed Nickel Oxide Hole Transport Layers in High Efficiency Polymer Photovoltaic Cells

The detailed characterization of solution-derived nickel (II) oxide (NiO) hole-transporting layer (HTL) films and their application in high efficiency organic photovoltaic (OPV) cells is reported. The NiO precursor solution is examined in situ to determine the chemical species present. Coordination complexes of monoethanolamine (MEA) with Ni in ethanol thermally decompose to form non-stoichiometric NiO. Specifically, the [Ni(MEA)2(OAc)]+ ion is found to be the most prevalent species in the precursor solution. The defect-induced Ni3+ ion, which is present in non-stoichiometric NiO and signifies the p-type conduction of NiO, as well as the dipolar nickel oxyhydroxide (NiOOH) species are confirmed using X-ray photoelectron spectroscopy. Bulk heterojunction (BHJ) solar cells with a polymer/fullerene photoactive layer blend composed of poly-dithienogermole-thienopyrrolodione (pDTG-TPD) and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) are fabricated using these solution-processed NiO films. The resulting devices show an average power conversion efficiency (PCE) of 7.8%, which is a 15% improvement over devices utilizing a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) HTL. The enhancement is due to the optical resonance in the solar cell and the hydrophobicity of NiO, which promotes a more homogeneous donor/acceptor morphology in the active layer at the NiO/BHJ interface. Finally, devices incorporating NiO as a HTL are more stable in air than devices using PEDOT:PSS.
A review of current inventory theory and its applications

This paper looks at the inventory-related models published during the last ten years from the systems point of view. A chart is given to show the broad oategories of inventory models. The paper first lists eleven quantifiable and four non-quantifiable variables (and their types) that go into inventory formulas, affect inventory decisions, and have already been identified by the researchers. Next, various research papers are grouped in six oategories based on similarities of approaches UBed by these papers. These categories are : (1) models for determining optimum inventory polioies, (2) lot size optimization, (3) optimization of various specific: management objectives, (4) models for optimizing highly specialized inventory situations, (5) application of advanced mathematical theories to inventory problems, and (6) models bridging the gap between theory and practice. Next a synthesized review of recently published models belonging to each individual category is presented, and salient features of individual...
A study of mistichthys luzonensis with special reference to conditions correlated with reduced size

A histological study has been made of the developing mid-gut or mesenteron of Melanoplus differentialis from diapause until after hatching. The primitive mid-gut consists at first of a single layer of squamous epithelium surrounding the yolk; to this is added later an outer layer. These two layers give rise to the muscular and connective tissue elements of the definitive mid-gut. Near the time of hatching, vitellophages which have been present in the yolk since earlier stages migrate peripherally to form a lining upon the inner surface of the primitive mid-gut. The vitellophage nuclei divide to form the smaller nuclei of the definitive epithelium of the mid-gut. The development of the definitive mesenteron from the primitive mid-gut takes place rapidly and occurs near the time of hatching.
Glucose does not activate nonadrenergic, noncholinergic inhibitory neurons in the rat stomach

We reported previously that intravenously administered d-glucose acts in the central nervous system to inhibit gastric motility induced by hypoglycemia in anesthetized rats. The purpose of this stu...
USE OF A MULTICHANNEL ANALYZER FOR ELECTRON PROBE MICROANALYSIS

A transistorized 400-channel multichannel analyzer attached to the electron probe microanalyzer has increased the versatility and decreased the time required for many analyses. Three types of application are illustrated. The multichannel analyzer replaces a scanning crystal spectrometer for quick identification and semiquantitative analysis of components. Quantitative analysis by mathematical unfolding of the energy spectra is made practical by the fast data collection of standard and unknown spectra; comparison of results by unfolding and from crystal spectrometer data shows differences of less than 4% of the amount present. Quantitative two-dimensional topographic display is obtained by multiscaler operation of the 400-channel memory system.
Comparative chloroplast and nuclear DNA analysis of Castanea species in the southern region of the USA

Boundaries between American Castanea species (Castanea dentata, the American chestnut and C. pumila var. pumila, the Allegheny chinkapin, and var. ozarkensis, the Ozark chinkapin) have been difficult to establish because of intraspecific variation, interspecific similarities and the incidence of chestnut blight, which has prevented trees from maturing. In this study, informative chloroplast (cp) DNA and nuclear sequences from Castanea taxa were analyzed to gain a better understanding of their phylogeography in North America. Our emphasis has been on the most southern Castanea population in the Appalachian region, known for its morphological diversity. This Ruffner Mountain (Alabama) population shows a high number of unique haplotypes, which can be divided into two main groups. One group shares homology with the widespread and evolutionarily recent C. dentata haplotype. The other group shares homology with American chestnuts and Allegheny chinkapin taxa from southern states. This group has been the result of recent and more ancient cp capture and hybridization, indicative of hybrid zone clustering and glacial refugial origin. The range of C. pumila must have been more extensive along the Coastal Plains region, since only a few mutations separate the Ozark chinkapin from the main Allegheny chinkapin haplotype. The geographic origin of the American Castanea species complex appears to be in the Gulf Coast region.
Basal Joint Osteoarthritis of the Thumb: A Prospective Trial of Steroid Injection and Splinting

Abstract Purpose There have been few prospective studies evaluating the results of nonsurgical treatment of a well-defined patient cohort with symptomatic basal joint osteoarthritis of the thumb. This prospective study uses a validated outcome instrument to examine the effectiveness of a single steroid injection and 3 weeks of splinting in patients with osteoarthritis in Eaton stages 1 to 4 with a minimum of 18 months of follow-up evaluation. Methods Thirty consecutive patients (30 thumbs) were studied prospectively to evaluate the efficacy of a single injection of corticosteroid into the trapeziometacarpal joint, followed by immobilization in a thumb spica splint for 3 weeks. All patients answered an outcome-based questionnaire (Disabilities of the Arm, Shoulder, and Hand) and were examined before injection, 6 weeks after injection, and at final follow-up examination (minimum, 18 months). Eaton radiographic stage was recorded by 3 independent observers. Results At 6 weeks 13 patients had improvement in pain intensity and 17 patients reported no symptomatic improvement. Twelve of those with relief at 6 weeks continued to have relief at long term follow-up evaluation (mean, 25 months). Of patients with long-term relief average grip strength of the affected thumb was 95% of contralateral side, whereas those without relief had grip strength values that were 60% of contralateral side. For those patients without relief at 6 weeks there was no improvement seen at later follow-up evaluation. Five patients with Eaton stage 1 disease had an average of 23 months of relief with nonsurgical treatment. In stage 2 and stage 3 disease 7 thumbs improved at 6 weeks after injection and 6 thumbs had long-term relief. In stage 4 disease, 6 thumbs had neither short-term nor long-term relief with the injection. Disease side, handedness, and smoking did not affect outcomes. At final follow-up evaluation 12 thumbs had had surgical treatment. Conclusions Steroid injection with splinting for the treatment of basal joint arthritis of the thumb provided reliable long-term relief in thumbs with Eaton stage 1 disease but provided long-term relief in only 7 of 17 thumbs with Eaton stage 2 and stage 3 basal joint arthritis.
Allopurinol administered prior to hepatic ischaemia in the rat prevents chemiluminescence following restoration of circulation.

Oxygen-derived free radicals produced during reperfusion may be responsible for the disturbed pathology which follows prolonged ischaemia. Measurement of hepatic chemilumine-scence (low level light emission resulting from the energy released during chemical reactions of free radicals) allowed determination of whether allopurinol could prevent formation of oxygen-derived free radicals during reperfusion of the ischaemic liver. While control animals demonstrated a burst of light emission shortly after reperfusion, the rats pretreated with allupurinol showed no evidence of chemiluminescence during either ischaemia or reperfusion. It is concluded that allopurinol may modify reperfusion-induced free radical formation and possibly ameliorate the organ damage which can follow ischaemia.
Evaluation of gravimetric techniques to estimate the microvascular filtration coefficient.

Microvascular permeability to water is characterized by the microvascular filtration coefficient (Kf). Conventional gravimetric techniques to estimate Kf rely on data obtained from either transient...
Removal of SO2 with oxygen in the presence of Fe(III)

A laboratory study of the aqueous oxidation of SO2 in the presence of Fe(III) and Fe(II) has been conducted. The SO2 concentration was 3930 ppm (3.93 × 10−3 atm or 398 Pa) in a gas stream with nitrogen and oxygen. The oxygen pressure was varied from 0 to 0.203 atmosphere. The initial concentration of Fe(III) ranged from 10−3 to 5-10−3 molar while that of Fe(II) was 5 × 10−3 molar. The temperatures were 298, 309.2, and 317.5 K. The solution pH was 1.83. The oxidation of SO2 is intensive and yields from 90 to 97 pct recovery of incoming SO2 when 5 × 10−3 molar Fe(III) and an oxygen pressure above 0.057 atmosphere are applied at 298 K. The reaction mechanism has been explained by determining the rate constants of the oxidation reactions from a kinetic model. The rate constants show that SO2 is mostly oxidized by oxygen through formation of ferric-sulfite complex and that regeneration of ferric ion is possible under a normal oxygen pressure. The activation energy of the oxidation has been determined and has been found to be 13.5 Kcal/mole.
Chiral sedimentation of extended objects in viscous media.

We study theoretically the chirality of a generic rigid object's sedimentation in a fluid under gravity in the low Reynolds number regime. We represent the object as a collection of small Stokes spheres or stokeslets and the gravitational force as a constant point force applied at an arbitrary point of the object. For a generic configuration of stokeslets and forcing point, the motion takes a simple form in the nearly free draining limit where the stokeslet radius is arbitrarily small. In this case, the internal hydrodynamic interactions between stokeslets are weak, and the object follows a helical path while rotating at a constant angular velocity $\ensuremath{\omega}$ about a fixed axis. This $\ensuremath{\omega}$ is independent of initial orientation and thus constitutes a chiral response for the object. Even though there can be no such chiral response in the absence of hydrodynamic interactions between the stokeslets, the angular velocity obtains a fixed nonzero limit as the stokeslet radius approaches zero. We characterize empirically how $\ensuremath{\omega}$ depends on the placement of the stokeslets, concentrating on three-stokeslet objects with the external force applied far from the stokeslets. Objects with the largest $\ensuremath{\omega}$ are aligned along the forcing direction. In this case, the limiting $\ensuremath{\omega}$ varies as the inverse square of the minimum distance between stokeslets. We illustrate the prevalence of this robust chiral motion with experiments on small macroscopic objects of arbitrary shape.
The Effect of Annealing on the Subpicosecond Breakdown Behavior of Hafnia Films

Subpicosecond laser induced breakdown of dielectric films has gained a great deal of attention in laser nano- and micromachining and in the development of optical coatings for the next generation of high-power ultrafast laser system. The understanding of the fundamental processes affecting the breakdown behavior and how they depend on the material properties and the film deposition is highly desirable for improving the coating performance. In the present work we compare the single and multiple pulse damage behavior of as-grown and annealed HfO2 films. Annealing can reduce the film absorption near the band edge but its impact on the single and multiple femtosecond pulse damage behavior remained open. Damage measurements with pairs of pulses of variable subpicosecond delay in bulk fused silica revealed a partial recovery toward single pulse behavior on a few hundred fs time scale. We investigate if such behavior also occurs in hafnia films and identify the time scale for a full recovery. Our experimental results are compared with existing theoretical models [1] , which allows us to suggest microscopic changes that occur during the annealing process.
The automorphisms of the linear congruence groups over Dedekind domains

Abstract Let o be a Dedekind domain with quotient field F and let M be an o -lattice on an n-dimensional vector space V over F. Let G be any one of the linear congruence groups TL n (M;a), Sl n (M;a),GL n (M;a) determined by an integral ideal a. If n ≥ 3, then every automorphism Λ of G can be uniquely expressed in exactly one of the forms ∧=P x °Φ g or ∧=P x °Psi; h where Pχ is a radial automorphism, Φg is associated with certain semilinear isomorphisms of V onto V and Ψh is associated with certain semilinear isomorphisms of V onto the dual space of V. For background and motivation see O. T. O'Meare, The automorphisms of the linear groups over any integral domain, J. reine angew. Math. 223 (1966), pp. 56–100. The proof uses results on the characterization of transvections by O. T. O'Meara (Group-theoretic characterization of transvections using CDC subgroups) and by H. Zassenhaus (Characterization of unipotent matrices).
First-principles calculation of positron lifetimes in solids

We present a first-principles approach for calculating the positron lifetime in metals. Convenient expressions are provided for the electron-positron correlation function and the enhancement factor. Calculations on a wide range of elemental metals and some monovacancies are found to be in excellent agreement with experiment. The approximations inherent in this approach and the treatment of the core-electron contribution are discussed.
Differential cross sections of 12C(d, p1)13C and 10B(d, p)11B below Ed = 3.0 MeV

Abstract In order to investigate the characteristics of low Q-value deuteron stripping reactions, differential cross sections of 12C(d, p1)13C (3.09 MeV state) have been measured at 11 bombarding energies between Ed = 2.088 and 0.900 MeV; and differential cross sections of 10B(d, p)11B, for the fourth, sixth, seventh, eighth, ninth, tenth and eleventh excited states have been measured at six bombarding energies between Ed = 3.000 MeV and 1.750 MeV. An examination of the ability of the plane wave, distorted wave and Coulomb wave Born approximation theories to predict the shape as well as the absolute cross sections has been made. Scattering angles at which the angular distributions break away from the Butler curved are compared with polology predictions.
Semiactive Control of Hunting Stability in Rail Vehicles

This paper discusses a methodology for improving hunting behavior in rail vehicles by semiactive control of suspension elements. This methodology focuses on increasing the critical velocity of hunting beyond the operational speed range. Earlier studies have shown that the critical velocity is most sensitive to the primary longitudinal stiffness, KPX . A higher primary longitudinal stiffness can significantly increase the critical hunting velocity of the rail vehicle. But, having high values of KPX is largely undesirable, since that would make the wheelset suspension very rigid. Any disturbance to the wheels due to imperfections in the rails will result in a forcing function in the equations of motion, thereby facilitating the transfer of the recurrent wheelset oscillations to the car body, leading to a poorer ride quality. As an alternative to using sustained high values of KPX throughout the ride, a semiactive approach has been attempted, whereby, a nominal value of KPX was assumed for the majority of the simulation time. On a need basis, this value was made to increase for limited portions of the oscillatory cycle. As an initial approach, the value of KPX was made to be a function of the wheelset lateral excursion. A moderate value of KPX was assumed for the duration of time that the wheelset lateral excursions were below a preset threshold value. Whenever the lateral displacement exceeded this threshold limit, the value of KPX was increased to 10 times the original value. It was thought that this approach would raise the critical hunting velocity, and drive the oscillations down towards the center. But simulation showed that this strategy barely improved the critical velocity. A subsequent approach was to make the value of KPX a function of the wheelset yaw displacement instead. This approach yielded a significant improvement in the critical velocity.Copyright © 2005 by ASME
Nontraded Goods and the Current Account

This paper investigates trade balance and current account behavior in response to various shocks when the economy produces and consumes both traded and nontraded goods. Previous analyses of these problems have interpreted current account behavior in terms of tension between parameters that measure intratemporal and intertemporal elasticity, respectively. This paper provides a simple general criterion for whether trade and current account behavior is “perverse”vis-a-vis the standard one-good model results: behavior is perverse if and only if traded and nontraded goods are Edgeworth complements; that is, if the cross-partial of the instantaneous utility function is positive.
Estimation Uncertainty and the Equity Premium

This paper studies a dynamic equilibrium model of asset prices in a partially observable exchange economy. It shows that the precautionary savings motive in response to estimation uncertainty can dominate the risk aversion effect, resulting in the reduction of the equity premium over short horizons. This exacerbates the equity premium puzzle. Over longer holding horizons, however, estimation uncertainty does induce higher risk premiums on equity over risk-free coupon bonds of matching maturities, as long-term bond yields are lowered due to the precautionary savings effect.
Quadratic Similarity Queries on Compressed Data

The problem of performing similarity queries on compressed data is considered. We study the fundamental tradeoff between compression rate, sequence length, and reliability of queries performed on compressed data. For a Gaussian source and quadratic similarity criterion, we show that queries can be answered reliably if and only if the compression rate exceeds a given threshold - the identification rate - which we explicitly characterize. When compression is performed at a rate greater than the identification rate, responses to queries on the compressed data can be made exponentially reliable. We give a complete characterization of this exponent, which is analogous to the error and excess-distortion exponents in channel and source coding, respectively. For a general source, we prove that the identification rate is at most that of a Gaussian source with the same variance. Therefore, as with classical compression, the Gaussian source requires the largest compression rate. Moreover, a scheme is described that attains this maximal rate for any source distribution.
A high-precision model of first-order reversal curve (FORC) functions for single-domain ferromagnets with uniaxial anisotropy

[1] Plots of the first-order reversal curve (FORC) function are used to characterize ferromagnetic particles in rocks. The function is based on classical Preisach theory, which represents magnetic hysteresis by elementary loops with displacement Hu and half width Hc. Using analytical and numerical integration of single-particle magnetization curves, a high-precision FORC function is calculated for a sample with randomly oriented, noninteracting, elongated single-domain (SD) particles. Some properties of the FORC function are independent of the distribution of particle orientations and shapes. There is a negative peak near the Hu axis, and the FORC function is identically zero for Hu > 0. The negative peak, previously attributed to particle interactions, is due to the increasing slope of a reversible magnetization curve near a jump. This peak is seen in experimental FORC functions of SD samples but not of samples with larger particles, probably because of Barkhausen jumps. The second feature is not seen in any experimental FORC function. A spread of the function to Hu > 0 can be caused by particle interactions or nonuniform magnetization.
Multiple dispersion regions in rigid polymeric systems

It is shown how chemical and colloidal heterogeneity can result in multiple dispersion regions of the mechanical or electrical loss factor as a function of temperature. Heterogeneity can be produced in several ways: (a) mechanical blending (mixing) of certain polymers, (b) non-uniform copolymerization, (c) block or graft polymerization, (d) external plasticization, and (e) certain types of molecular weight distribution. Specific examples are given to demonstrate the effect.
Molecular aging of the brain, neuroplasticity, and vulnerability to depression and other brain-related disorders.

The increased risk for neurodegenerative and neuropsychiatric disorders associated with extended lifespan has long suggested mechanistic links between chronological age and brain-related disorders, including depression, Recent characterizations of age-dependent gene expression changes now show that aging of the human brain engages a specific set of biological pathways along a continuous lifelong trajectory, and that the same genes that are associated with normal brain aging are also frequently and similarly implicated in depression and other brain-related disorders. These correlative observations suggest a model of age-by-disease molecular interactions, in which brain aging promotes biological changes associated with diseases, and additional environmental factors and genetic variability contribute to defining disease risk or resiliency trajectories. Here we review the characteristic features of brain aging in terms of changes in gene function over time, and then focus on evidence supporting accelerated molecular aging in depression. This proposed age-by-disease biological interaction model addresses the current gap in research between “normal” brain aging and its connection to late-life diseases. The implications of this model are profound, as it provides an investigational framework for identifying critical moderating factors, outlines opportunities for early interventions or preventions, and may form the basis for a dimensional definition of diseases that goes beyond the current categorical system.
The vascular marker soluble fms-like tyrosine kinase 1 is associated with disease severity and adverse outcomes in chronic heart failure.

Objectives We sought to evaluate placental growth factor (PlGF) and soluble Fms-like tyrosine kinase 1 (sFlt-1) as clinical biomarkers in chronic heart failure (HF). Background Vascular remodeling is a crucial compensatory mechanism in chronic HF. The angiogenic ligand PlGF and its target receptor fms-like tyrosine kinase 1 modulate vascular growth and function, but their relevance in human HF is undefined. Methods We measured plasma PlGF and sFlt-1 in 1,403 patients from the Penn Heart Failure Study, a multicenter cohort of chronic systolic HF. Subjects were followed for death, cardiac transplantation, or ventricular assist device placement over a median follow-up of 2 years. Results The sFlt-1 was independently associated with measures of HF severity, including New York Heart Association functional class (p 379 pg/ml) had a 6.17-fold increased risk of adverse outcomes (p Conclusions Our findings support a role for sFlt-1 in the biology of human HF. With additional study, circulating sFlt-1 might emerge as a clinically useful biomarker to assess the influence of vascular remodeling on clinical outcomes.
ELISA: Structure-Function Inferences based on statistically significant and evolutionarily inspired observations

The problem of functional annotation based on homology modeling is primary to current bioinformatics research. Researchers have noted regularities in sequence, structure and even chromosome organization that allow valid functional cross-annotation. However, these methods provide a lot of false negatives due to limited specificity inherent in the system. We want to create an evolutionarily inspired organization of data that would approach the issue of structure-function correlation from a new, probabilistic perspective. Such organization has possible applications in phylogeny, modeling of functional evolution and structural determination. ELISA (Evolutionary Lineage Inferred from Structural Analysis, http://romi.bu.edu/elisa) is an online database that combines functional annotation with structure and sequence homology modeling to place proteins into sequence-structure-function "neighborhoods". The atomic unit of the database is a set of sequences and structural templates that those sequences encode. A graph that is built from the structural comparison of these templates is called PDUG (protein domain universe graph). We introduce a method of functional inference through a probabilistic calculation done on an arbitrary set of PDUG nodes. Further, all PDUG structures are mapped onto all fully sequenced proteomes allowing an easy interface for evolutionary analysis and research into comparative proteomics. ELISA is the first database with applicability to evolutionary structural genomics explicitly in mind. Availability: The database is available at http://romi.bu.edu/elisa.
The heterogeneity of Jessner's lymphocytic infiltration of the skin: Immunohistochemical studies suggesting one form of perivascular lymphocytoma

Seventeen patients (six women and 11 men) with Jessner's lymphocytic infiltration of the skin were studied. Nineteen biopsy specimens were analyzed with the following monoclonal antibodies: UCHL1 (T cells), 4KB5, L26 (B cells), LN1 (germinal center B cells), and BerH2 (Ki-1+ cells). Routine direct immunofluorescence was performed on 15 specimens. In 10 of 19 specimens both B and T cells were demonstrated; the B cells were in close proximity to small blood vessels. In 50% of these cases the B cell component expressed LN1 positivity. We use the term perivascular lymphocytoma to describe this pattern. Nine specimens showed T cells only. No Ki-1+ cells were detected. Routine immunofluorescence studies were performed on 15 specimens. In six of seven specimens in which there was a mixed cell population of B and T cells, results were completely negative. In contrast, six of the remaining eight specimens with a predominantly T cell population revealed weak, patchy, granular, positive labeling for immunocomponents, particularly IgM and C3 at the basement membrane. These findings suggest that Jessner's lymphocytic infiltration is a heterogeneous disorder with at least two separate immunophenotypes. The finding of perivascular follicular center differentiation in more than half the specimens suggests a possible relationship in these cases to other benign lymphoid hyperplasias (pseudolymphomas).
Intravesical oncolytic viral therapy using attenuated, replication-competent herpes simplex viruses G207 and Nv1020 is effective in the treatment of bladder cancer in an orthotopic syngeneic model.

SPECIFIC AIMSAttenuated, replication-competent herpes simplex virus mutants have recently been shown to replicate within and kill tumor cells while remaining at low pathogenicity to normal tissues....
Immigrant Latinas’ Conceptualizations of Intimate Partner Violence

This study was a qualitative investigation of the conceptualization of intimate partner violence (IPV) among immigrant Latinas. The research approach used was naturalistic inquiry: conducting research maintaining minimal interference with the phenomenon of interest. Findings revealed that the immigrant Latinas in this study were aware of the poor quality of intimate relationships in their community, were knowledgeable about IPV, and understood that IPV is an extensive problem in the immigrant Latino community. In addition, the women recognized gender disparities and other ecological factors as central issues affecting their intimate relationships and leading to IPV.
Oculomotor strategy of an avian ground forager: tilted and weakly yoked eye saccades

Many bird species are capable of large saccadic eye movements that can result in substantial shifts in gaze direction and complex changes to their visual field orientation. In the absence of visual stimuli, birds make spontaneous saccades that follow an endogenous oculomotor strategy. We used new eye tracking technology specialized for small birds to study the oculomotor behavior of an open-habitat, ground foraging songbird, the European starling ( Sturnus vulgaris ). We found that starlings primarily move their eyes along a tilted axis 13.46° downwards anteriorly and upwards posteriorly, which differs from the axis parallel to the horizon employed by other species. This tilted axis could enhance foraging and anti-predator strategies while starlings are head-down looking for food, allowing them to direct vision between the open mandibles to visually inspect food items and above and behind the head to scan areas where predators are more likely to attack. We also found that starlings have neither fully conjugate saccades (e.g., humans) nor independent saccades (e.g., chameleons). Rather, they exhibit weakly yoked saccades where the left and right eyes move at the same time but not the same magnitude. Functionally, weakly yoked saccades may be similar to independent saccades in that they allow the two eyes to concomitantly perform different tasks. The differences between the oculomotor strategies of studied species suggest eye movements play variable but important roles across bird species with different ecological niches.
Transition Metal Oxide Core-Shell Nanowires: Generic Synthesis and Transport Studies

A generic non-equilibrium synthesis technique has been developed to produce novel transition metal oxide nanowires, including YBa2Cu3O6.66, La0.67Ca0.33MnO3, PbZr0.58Ti0.42O3, and Fe3O4. Key to our success is the growth of vertically aligned single-crystalline MgO nanowires, which worked as excellent templates for epitaxial deposition of the desired transition metal oxides and led to high-quality core−shell nanowires. Transport studies on La0.67Ca0.33MnO3 nanowires have revealed the remarkable persistence of metal−insulator transition and magnetoresistance down to nanometer scale. Our technique will enable various in-depth studies such as phase transition in nanoscale oxides and may pave the way for novel applications of these fascinating materials.
Informal Risk Sharing, Index Insurance and Risk-Taking in Developing Countries

This paper presents preliminary findings from a research project that examines the interaction between informal risk sharing, index insurance and risk-taking. We have randomized rainfall insurance contracts offered to cultivating and landless households in a set of Indian villages where pre-existing census data on caste networks allows us to characterize the nature and extent of informal risk sharing. In a series of papers, we study (a) how informal risk sharing mediates the demand for index insurance, (b) whether index insurance or informal indemnification allows farmers to invest in risky technologies, and (c) the general equilibrium effects of offering insurance contracts to cultivators or to agricultural laborers.
Nontraditional signal processing techniques employing linear transforms

Nontraditional transform domain signal processing techniques, applied to two important signal processing areas are given. In the first technique, audio and video signals are represented using the superposition of nonorthogonal basis functions. It is shown that this nontraditional representation yields efficient compression algorithms, i.e, for the same bit rate, higher representation accuracy is achieved, or for the same representation accuracy, lower bit rate is required, relative to previously reported methods. In the second technique, signal autocovariance formulations in the transform domains are presented. It is shown that these formulations yield practical solutions to important signal processing classification and recognition problems. This is because these nontraditional autocovariance formulations result in considerable reduction in the storage requirements and the computational complexity, without sacrificing the signal representation accuracy associated with the traditional autocovariance formulation in the time and/or in the spatial domains.
A controlled trial of calcitonin therapy for the prevention of post-liver transplantation atraumatic fractures in patients with primary biliary cirrhosis and primary sclerosing cholangitis.

Abstract Background/Aims : Accelerated bone loss occurs early after liver transplantation (OLT) and, in cholestatic patients with pre-existing osteopenia, causes spontaneous fracturing. This study aimed to investigate the efficacy of calcitonin, a powerful inhibitor of bone resorption, in preventing or reducing the accelerated rate of bone loss and fracturing which occurs in patients with primary biliary cirrhosis and primary sclerosing cholarigitis early after OLT. Methods : Sixty-three patients undergoing OLT for primary biliary cirrhosis ( n =26) and primary sclerosing cholarigitis ( n =37) were randomized to receive: (a), 100 IU/day of salmon calcitonin subcutaneously for the first 6 months posttransplant; or (b), no therapy. At pretransplant, and at 4 and 12 months after OLT, patients were investigated clinically, biochemically, by bone mineral density of the lumbar spine, and by radiographs of the thoracolumbar spine, chest and site of any bone pain. Results : The bone mineral density of the lumbar spine fell equally at 4 months in both groups, from 0.85 to 0.81 g/cm 2 in calcitonin-treated patients ( n =29) and from 0.88 to 0.82 g/cm 2 in controls ( n =34); at 12 months, both groups had stabilized to 0.83 g/cm 2 . Fracturing was the same in both groups. Conclusions : Calcitonin therapy for the first 6 months after OLT is unable to prevent or reduce accelerated bone loss or spontaneous fractures which occur in the first posttransplant year.