cssi/SciSciGPT-SciSciNet huggingface dataset:
Concept annotation and search space decrement of digital photos using optical context information

A modern digital camera is not just a single sensor capturing light. It is an ensemble of different sensors which capture independent contextual information about the photo shooting event. This is stored as metadata in the image. In this paper, we demonstrate how the optical metadata (data related to the optics of the camera) can be retrieved, interpreted and used along with content information for organizing and indexing digital photos. Our model is based on the physics of vision and operation of a camera. We use our algorithm on images from personal photo albums. Our results show that the optical metadata improves annotation performance and decreases the search space for retrieval.
Glomerular filtration in single nephrons.

In recent years as many investigators have turned their attention to the study of tubular transport processes in individual nephrons, it has become increasingly important to measure and to understand the factors that determine the filtration rate of single nephrons (SNGFR).More frequent measurements of SNGFR have yielded a great deal of new information concerning the function of individual glomeruli.An inevitable consequence of more information, however, seems to be controversy.Controversial matters that have arisen in recent studies of SNGFR include questions about the most appropriate technique of making the measurements, as well as disagreement about conclusions that have been drawn from the results of these measurements. Knowing the rate of glomerular filtration in single nephrons is crucial to the determination of absolute rates of reabsorption or secretion by the renal tubules.The excretion rate of sodium, for example, has long been known to be dependent on the filtered load of sodium.Assessment of factors involved in the control of sodium reabsorption depends on knowing the rate at which sodium enters and leaves a tubule segment.Measurement of SNGFR is also important to investigation of the regulation of the filtration process itself.It is likely that future clarification of the still unknown mechanisms controlling filtration rate will come from studies where SNGFR is measured as the functional environment of that nephron unit is controlled. Factors that affect SNGFR can presently be grouped into those determined by the functional state of the experimental animal and those that result from technical difficulties and artifacts.It appears that SNGFR is influenced by age [1, 2], body weight [1, 2], the number of kidneys present [3], hydration [4], extracellular fluid volume [5], and the genetic makeup [6, 7].The nephron site at which micropuncture collections are made – proximal or distal, superficial or deep – also has to be considered.
Saccharomyces cerevisiae RRM3, a 5' to 3' DNA helicase, physically interacts with proliferating cell nuclear antigen

Proliferating cell nuclear antigen (PCNA) plays an essential role in eukaryotic DNA replication, and numerous DNA replication proteins have been found to interact with PCNA through a conserved eight-amino acid motif called the PIP-box. We have searched the genome of the yeast Saccharomyces cerevisiae for open reading frames that encode proteins with putative PIP-boxes and initiated testing of 135 novel candidates for their ability to interact with PCNA-conjugated agarose beads. The first new PCNA-binding protein identified in this manner is the 5′ to 3′ DNA helicase RRM3. Yeast two-hybrid tests show that N-terminal deletions of RRM3, which remove the PIP-box but leave the helicase motifs intact, abolish the interaction with PCNA. In addition, mutating the two phenylalanine residues in the PIP-box to alanine or aspartic acid reduces binding to PCNA, confirming that the PIP-box in RRM3 is responsible for interaction with PCNA. The results presented here suggest that the RRM3 helicase functions at the replication fork.
Silyl and bis(silyl)hydride complexes of ruthenium: Effect of ancillary groups on the oxidative addition of Si-H bonds

Abstract Ruthenium alkyl complexes Cp(PMe 3 ) 2 RuCH 2 SiMe 3 ( 2 ) and Cp(PPh 3 ) 2 RuMe ( 3 ) reacted with hydrosilanes forming ruthenium silyl and/or bis(silyl)hydride complexes. Complex 2 reacted with HSiR 3 at 100°C forming the corresponding silyl complexes Cp(PMe 3 ) 2 RuSiR 3 [SiR 3 = SiCl 3 ( 4 ), SiMeCl 2 ( 5 ), SiMe 2 Cl ( 6 )] in high yields. At 125–150°C, 2 reacted with HSiEt 3 giving a mixture of the silyl Cp(PMe 3 ) 2 RuSiEt 3 ( 7 ) and the bis(silyl)hydride Cp(PMe 3 )Ru(SiEt 3 ) 2 H ( 8 ); this mixture can be converted solely to 7 upon reaction with PMe 3 . Complex 3 reacted with HSiEt 3 at 100°C forming Cp(PPh 3 ) 2 RuSiEt 3 ( 9 ). The reaction of 3 with neat HSiCl 3 at 100°C forms a mixture of Cp(PPh 3 )Ru(SiCl 3 ) 2 H ( 10 ) and Cp(PPh 3 ) 2 RuSiCl 3 ( 11 ), with 10 being the major product. At lower concentrations of HSiCl 3 ( 3 forms mixtures of 10 and 11 but with 11 being the major product. Mixtures of 10 and 11 can be converted to 11 upon reaction with excess PPh 3 . Similarly, 11 reacts with neat HSiCl 3 to generate a mixture of 10 and 11 . The effects of the ancillary ligands on ruthenium and the nature of the hydrosilane on the rate and course of reaction are also discussed.
Retinoblastoma family genes

The retinoblastoma gene Rb was the first tumor suppressor gene cloned, and it is well known as a negative regulator of the cell cycle through its ability to bind the transcription factor E2F and repress transcription of genes required for S phase. Although over 100 other proteins have been reported to interact with Rb, in most cases these interactions are much less well characterized. Therefore, this review will primarily focus on Rb and E2F interactions. In addition to cell cycle regulation, studies of Rb and E2F proteins in animal models have revealed important roles for these proteins in apoptosis and differentiation. Recent screens of Rb/E2F target genes have identified new targets in all these areas. In addition, the mechanisms determining how different subsets of target genes are regulated under different conditions have only begun to be addressed and offer exciting possibilities for future research.
An Emotional Appraisal Theory of How Subordinates Experience Abusive Supervision Over Time

Drawing on emotional appraisal and coping theory, we present a multiphase framework that delineates how subordinates perceive, experience, and respond to abusive supervision over time. Our framewor...
Diathesis-stress models of psychopathology: A quantitative genetic perspective

Abstract When genetics is considered in diathesis-stress models of psychopathology, it is often assumed that heredity provides the diathesis and environmental factors are responsible for the stressor. We discuss two quantitative genetic models relevant to the diathesis-stress construct. One model focuses on genotype-environment interaction, which is the usual way in which genetic influence is represented in diathesis-stress models. A second model—genotype-environment correlation—provides an alternative that represents both genetic and environmental influences relevant to the development of psychopathology. Implications of these models for clinical research are discussed.
COST, PRICE, AND THE CONTRACTING RELATION: A CASE STUDY

The paper describes the failure of a project in which a group of computer specialists tried to help a group of scholars by automating a conference registration system. Although there was a warm and personal relationship between the group liaisons, difficulties arose because there was no agreed-on mechanism to allocate priorities and resources. The author analyzes the price and cost mechanisms which might have been used to communicate complex trade-offs and thus avert the ensuing disaster.
Fourier transform technique with refinement in the frequency domain for the synthesis of optical thin films

An optical thin-film synthesis technique combining a Fourier transform approach with the refinement of design parameters in the Fourier space is proposed. The theory and numerical examples are described.
Smeared-photographic-image deblurring utilizing white-light-processing technique

A white-light-processing technique for smeared-photographic-image restoration is described. A simple technique of synthesizing a complex deblurring spatial filter is also given. Experimental demonstrations of smeared-image deblurring with a white-light-processing technique are provided. Compared with the coherent-processing technique, the white-light technique offers artifact-noise suppression, and the processing system is simple, versatile, and economicaL. We note that the white-light-processing technique is suitable for smeared-color-image restoration.
Nicotine Binding to Native and Substituted Peptides Comprising Residues 188–207 of Nicotinic Acetylcholine Receptor α1, α2, α3, α4, α5, and α7 Subunits

Abstract Structural determinants of L-[ 3 H]nicotine binding to synthetic peptides comprising residues 188–207 of nicotinic acetylcholine receptor α subunits were invesitigated by equilibrium binding analysis. Two binding components were detected, one of low affinity ( K d ∼ 1.5 μM) that did not differ significantly among peptides and another of high affinity. The high affinity binding component was higher for the neuronal peptides ( K d = 14–23 nM) than the muscle α1 peptides ( K d = 52 nM). The following nonconservative substitutions in the α4 peptide resulted in a significant decrease in nicotine affinity for the peptide: Y190A, Y190D, C192G, E195A, E195–, P199A, P199–, and Y203A. Substitution of α4P199 with a leucine which is present in the α1 sequence decreased the affinity of the α4 peptide for nicotine and substitution of α1L199 with a proline (α4) or a glutamine (α3) increased the affinity of the α1 peptide. It is concluded that aromatic residues contribute to the binding site for nicotine on the α4 subunit and that the residue present at position 199 partly determines differences in nicotine affinity for different α subunits.
Effects of Cognitive Ability, Task Knowledge, Information Sharing, and Conflict on Group Decision-Making Effectiveness

This article examines the effects of group composition (i.e., member task-related knowledge and cognitive ability) on information sharing, conflict, and group decision effectiveness in a complex low-fidelity management simulation. Controversy within the group over the strategy to employ was strongly related to interpersonal conflict between members, whereas group-level indices of cognitive ability and task knowledge were the best predictors of decision-making effectiveness. As in past studies using relatively simple choice tasks, groups exhibited biased information sampling and generally failed to identify the best course of action suggested by their collective information. The discussion highlights the need for further research using theoretical models that incorporate both composition and process factors.
Supersymmetric partners of oblique corrections

Abstract We discuss the violation of the equality of the gauge coupling and gaugino coupling in the presence of soft supersymmetry breaking. Although this is a hard supersymmetry breaking effect, there are finite contributions to this difference that can be determined as a function of the soft supersymmetry breaking masses. The largest sources of this difference are the “super-oblique” corrections, which can be enhanced by a multiplicity factor and a logarithm of the soft supersymmetry breaking mass. This is to be contrasted to standard oblique corrections to the electroweak sector, which decouple for large supersymmetry breaking. We show that these parameters can be relatively large, particularly in models of supersymmetry breaking motivated by solving the supersymmetric flavor problem. We also perform a detailed study of the non-oblique corrections for the example of squark decay. We find that they can be significant, and should be accounted for in the theoretical prediction.
Interaction between the oceanic mesoscale and the surface mixed layer

Abstract A semianalytic solution to the mutual interaction of a Rossby wave and the surface mixed layer is derived. The presence of the mixed layer causes neither damping nor growth of the interior motions; modal structures and frequencies are simply altered by a small amount. Rossby wave motions perturb the surface boundary layer quite significantly. Vertical transports arising from both the wave itself and its interaction with the Ekman flow cause entrainment and detrainment and create complex remnant layer structures below the mixed layer. The semianalytic solution is used to benchmark a coupled quasigeostrophic and surface boundary layer numerical model. Intricate numerical techniques are required to maintain the fidelity of the mixed layer-remnant layer interface and the structures below it.
Experimental authigenesis of phyllosilicates from feldspathic sands

Hydrothermal experiments with primary detrital components of feldspathic sands (orthoclase, albite, quartz, and calcite) were conducted to simulate possible diagenetic changes in geosynclinal sedimentary accumulations and the geothermal reservoir of the Imperial Valley area, California. Phyllosilicate and zeolite mineralization was produced at 200°C and 1 Kb Ph2o and at 300°C and 1 and 3 Kb Ph2o. Scanning electron microscope examination of the detrital grains shows the development of authigenic minerals and solution features. Phyllosilicate development occurred as dense surface coatings on orthoclase crystals in concentrated brines and as scattered grain clusters in dilute brines. Cation concentration is considered to be a controlling factor in phyllosilicate formation and growth. During formation the phyllosilicate crystals appear to utilize the surficial feldspar lattice structure as a preferred growth site. Electron diffraction studies indicate the crystals are a 1 Md mica similar to illite. Initial phyllosilicate formation occurs principally on orthoclase in systems containing this mineral, but is disseminated on other mineral surfaces in systems without orthoclase. This experimental development of authigenetic illite via the destruction of potassium feldspar may offer a potential mechanism to help explain the resulting mineralogy of diagenetic processes occurring in natural sediments such as in feldspathic sands and argillaceous sediments.
GREEN'S FUNCTIONS FOR SUBSURFACE THERMAL STRESSES DUE TO SURFACE HEATING

Abstract When two bodies slide against each other, the resulting frictional heating leads to thermoelastic stresses that can play an important part in the mechanism of wear and surface fatigue failure. The contact pressure and heat input distributions are influenced by the thermal distortion of the bodies and vary in time as a result of wear. To investigate thermally induced failures in such systems, we therefore require a general numerical algorithm for calculating subsurface stresses for any arbitrary distribution of heat input in time and space. Green's Junctions for the surface values of displacement and temperature for the half-plane were given in the literature. In this paper, we derive appropriate Green's Junctions for the stresses and temperatures at a general point below the surface of the half-plane. Particular attention is paid to the presentation of the results in a form convenient for efficient numerical computations.
Coagulant and esterase activities of thrombin and Bothrops atrox venom

Abstract Thrombin and Bothrops atrox coagulant are similar enzyme proteins. Contrary to the general contention, TAME hydrolyzing enzyme was found by the authors to differ from the coagulant component of both the thrombin preparation and the B. atrox venom. With the thrombin preparation and B. atrox venom, the hydrolysis of synthetic amino acid esters and transformation of fibrinogen to fibrin appeared to be catalyzed by two different enzyme proteins.
HUNGRY SPIDERS AREN'T AFRAID OF THE BIG BAD WOLF SPIDER

Abstract Foraging behavior in spiders can be influenced by a variety of factors. Here we investigate the effects of hunger and predation risk on feeding behavior in the wolf spider Pardosa milvina (Hentz 1877) (Araneae, Lycosidae). Pardosa milvina is preyed upon by the larger wolf spider, Hogna helluo (Walckenaer 1837), and responds with appropriate antipredator behavior to the silk and feces of this species. We predicted that hungry Pardosa milvina would be more likely to forage and consume prey under predation risk than satiated individuals. We found that hungry Pardosa under predation risk consumed as many prey as spiders not under predation risk. However, satiated Pardosa consumed significantly fewer prey when under predation risk. Our data suggest that the animal's energetic needs are weighed against the risks of foraging when predators may be present.
LIGHTNING SKY, RAIN, AND THE MAIZE GOD: The Ideology of Preclassic Maya Rulers at Cival, Peten, Guatemala

Research in the northeastern Peten region at Holmul and nearest minor centers shows a complex history of public ritual activity from the Middle Preclassic onward. Patterns of public architecture, monumental sculpture, iconography, caches, and burials at sites such as Holmul and Cival document early development of the ideology of Maya kingship. Late Preclassic monumental sculptures adorning large pyramid temples provide immediate and elaborate metaphors for the ancestral patrons of emerging dynasts. Middle Preclassic architecture and caches are encoded with the ideological program of the earliest ruling institutions, incorporating themes of cosmological order; sun, water, and maize deities; the agricultural cycle; and ancestor veneration. All of these early remains are found in the sacred space of the first “E-group” plazas.
Modality-specific axonal regeneration: toward selective regenerative neural interfaces.

Regenerative peripheral nerve interfaces have been proposed as viable alternatives for the natural control of robotic prosthetic devices. However, sensory and motor axons at the neural interface are of mixed submodality types, which difficult the specific recording from motor axons and the eliciting of precise sensory modalities through selective stimulation. Here we evaluated the possibility of using type-specific neurotrophins to preferentially entice the regeneration of defined axonal populations from transected peripheral nerves into separate compartments. Segregation of mixed sensory fibers from dorsal root ganglion neurons was evaluated in vitro by compartmentalized diffusion delivery of nerve growth factor (NGF) and neurotrophin-3 (NT-3), to preferentially entice the growth of TrkA+ nociceptive and TrkC+ proprioceptive subsets of sensory neurons, respectively. The average axon length in the NGF channel increased 2.5 fold compared to that in saline or NT-3, whereas the number of branches increased 3 fold in the NT-3 channels. These results were confirmed using a 3-D “Y”-shaped in vitro assay showing that the arm containing NGF was able to entice a 5-fold increase in axonal length of unbranched fibers. To address if such segregation can be enticed in vivo, a “Y”-shaped tubing was used to allow regeneration of the transected adult rat sciatic nerve into separate compartments filled with either NFG or NT-3. A significant increase in the number of CGRP+ pain fibers were attracted towards the sural nerve, while N-52+ large diameter axons were observed in the tibial and NT-3 compartments. This study demonstrates the guided enrichment of sensory axons in specific regenerative chambers, and supports the notion that neurotrophic factors can be used to segregate sensory and perhaps motor axons in separate peripheral interfaces.
Determinants of Funding Strategies and Actuarial Choices for Defined‐Benefit Pension Plans*

This paper examines the effects of firms' financial and pension profiles on their funding strategies and actuarial choices. The paper uses reports filed by individual pension plans with the Department of Labor under the requirements of the Employee Retirement Income Security Act of 1974 for the analysis. Evidence reported in the paper shows that as firms become overfunded, they make conservative actuarial choices to avoid visibility costs, and that as firms become underfunded, they make liberal actuarial choices to avoid visibility costs. As the annual contributions increase relative to the permissible contribution ranges, firms make conservative actuarial choices to minimize penalties and maximize tax benefits. As the annual contributions decrease relative to the permissible contribution ranges, firms make liberal actuarial choices to minimize penalties and maximize tax benefits. The larger the profitability, cash flow from operations, and tax liability, and the smaller the debt of a firm, the higher the likelihood that the firm's managers will make conservative actuarial choices to maximize contributions. Conversely, the smaller the profitability, cash flow from operations, and tax liability, and the larger the debt of a firm, the higher the likelihood that the firm's managers will make liberal actuarial choices to minimize contributions. This evidence, which is consistent with the hypothesis of funding management, can aid the Internal Revenue Service (IRS) in regulating the defined-benefit pension plans more effectively and help plan beneficiaries to manage their retirement portfolios more efficiently. The debiasing method developed in the paper can provide investors and creditors with the tools to identify the discretionary components of pension liabilities and thereby value firms more efficiently.
Heuristic reduction of gyro drift in vehicle tracking applications

This paper pertains to the reduction of measurement errors due to drift in rate gyros used for tracking the position of moving vehicles. In these applications, gyros and odometry are often used to augment GPS when GPS reception is unavailable. Drift in gyros causes the unbounded growth of errors in the estimation of heading, rendering low-cost gyros almost entirely useless in applications that require good accuracy for more than just a few seconds or minutes. Our proposed method, called 'Heuristic Drift Reduction' (HDR), applies a unique closed-loop control system approach to estimate drift in real time and remove the estimated drift instantaneously from the gyro reading. The paper presents results of experiments, in which a gyro-equipped car was driven hundreds of miles on highways, rural roads and city streets. HDR reduced the average heading error over all of these drives by one order of magnitude.
Catabolism of apoprotein A-1 of HDL in normal and nephrotic rats☆

Abstract High density lipoprotein was isolated from the plasma of control and puromycin aminonucleoside nephrotic rats and labeled with 125I. It was injected into control and nephrotic rats and the plasma analyzed after 3 min, 5 hr, and 20 hr. High density lipoprotein was isolated and the specific activity of apo A-I determined following apoprotein separation using SDS-polyacrylamide gel electrophoresis. The distribution of labeled apoproteins was determined in whole plasma by SDS-gel filtration column chromatography and the plasma concentration of apo A-I was calculated from its specific activity and the total plasma apo A-I radioactivity. A 3 min to 5 or 20 hr fractional catabolic rate was calculated. When multiplied by the plasma concentration of apo A-I, an estimate of the absolute catabolic rate was obtained. When injected into normal animals, the high density lipoprotein apo A-I had similar catabolic rates whether derived from control or nephrotic rat plasma, averaging 65 and 48 μg of apoprotein per ml of plasma per hr at 5 or 20 hr, respectively. Labeled HDL was injected into nephrotic rats of varying degrees of severity. The moderately nephrotic rats with plasma cholesterol levels averaging 177 mg/dl had apo A-I levels that were 3.6 times that of controls (1799 ± 195 μg/ml) and 2.4-fold increases in apo A-I catabolic rates (134 ± 28.9 μg/ml plasma/hr). The severely nephrotic rats with cholesterol concentrations averaging 396 mg/dl had apo A-I levels 7.1 times that of the controls (3533 ± 220 μg/ml) while the catabolic rate was 2.7 times the control rate (153 ± 19.5 μg/ml/hr), which was not a significant increase beyond that of the moderately nephrotic group. It was concluded that compositional differences of HDL resulting in an increased proportion of apo A-I, as in nephrotic rat plasma, do not affect apo A-I metabolism. The high levels of apo A-I in the plasma of nephrotic rats is due to increased hepatic synthesis that results in an expansion of the pool size and saturation of catabolic pathways. Small increases in apo A-I synthesis lead to large increases in the plasma concentration, an observation that may be important in the regulation of HDL levels that are known to be correlated with a decreased incidence of atherosclerosis.
Room at the piston top contributions of combustion science to engine design

Charles F. Kettering, “Boss Ket,” the founder of the General Motors Research Laboratories, once said: “It's so simple to explain [the automobile engine] by saying, you take a charge of gasoline and air into the cylinder, compress it and ignite it with a spark, and it explodes and pushes the piston down, and that makes your car go … If you stop right there, it is a logical explanation. But what does the spark do? What do you mean by combustion? We don't know why or how the spark sets off that explosion of gas … So I say, quite solemnly, that we haven't the slightest idea what really makes the contraption run. We call the reaction ‘combustion’ because it nicely conceals our lack of knowledge on just what takes place in the engine cylinder. I just don't think we can live in this atmosphere of ignorance about what goes on there when our whole business depends on it” [1].
Electronic Spectrum and Ultraviolet Optical Properties of Crystalline MgO

Magnesium oxide single crystal electronic spectrum obtained from reflectance spectra, observing large plasma peak in energy loss function
Substratum-binding neurite-promoting factors: relationships to laminin

Abstract Recently, much progress has been made in the characterization of substratum-binding proteins which stimulate neurite regeneration from cultured neurons. Purified extracellular matrix proteins including collagens type I and IV, fibronectin and laminin have been reported by several laboratories to be active neurite promoters in vitro , although laminin appears to be the most potent factor in these assays. Two neurite promoting factors have also been purified from rat RN22 schwannoma and bovine corneal endothelial cell conditioned media and found to contain laminin as a component. The relationships between these factors and laminin are discussed.
Incentive compatible resource allocation in concurrent design

This article presents an approach that a manager can use to allocate resources needed to design a system among the members of a concurrent design team. The system being designed is assumed to be composed of a number of subsystems, each designed by a different engineer. These engineers possess private information about the performance of their subsystem as a function of the design resources that they are allocated. This article shows how the manager of such a concurrent design project can induce rational self-interested engineers to reveal truthfully their private subsystem performance functions. This is accomplished through an incentive contract that ties each engineer’s pay to the contribution of their subsystem to the performance of the overall system. The approach builds from a Vickrey–Clarke–Groves mechanism to achieve, as an ex-post Nash equilibrium, truthful reporting of private subsystem performance functions by risk-neutral agents.
Study of energy vs misorientation for grain boundaries in gold by crystallite rotation method—II. Tilt boundaries and mixed boundaries

Abstract In Part I [ Acta metall . 33 , 1113 (1985)] small gold crystallites were welded to thin film single crystal gold substrates at different controlled misorientations to produce pure twist boundaries in the neck regions which could be observed directly by transmission electron microscopy. In the present work these experiments were extended to include pure tilt and also mixed (tilt/twist) boundaries. Upon annealing, the crystallites untilted and untwisted into several particular misorientations in order to reduce the boundary energy. The untilting and untwisting occurred by the observed climb of edge grain boundary dislocations (GBDs) and glide of screw GBDs respectively. The directions of the rotations were generally consistent with a boundary energy vs tilt/twist “surface” constructed on the basis of the structural unit/GBD model for grain boundaries. Kinetic models for the untilting indicated that the climbing edge GBDs acted as efficient line sources/sinks and that the diffusional transport was controlled by either lattice diffusion or edge GBD core diffusion for low angle pure tilt boundaries and by grain boundary diffusion for high angle mixed boundaries.
Maximal orders over valuation rings

Abstract In this paper we study maximal orders over commutative valuation rings in central simple algebras. We are particularly interested in maximal orders which are either Bezout or semihereditary. We construct a class of Bezout maximal orders and a class of semihereditary maximal orders, and show that for any valuation ring V (resp. V with value group Z m), any Bezout (resp. semihereditary) maximal order over V belongs to the class constructed. Furthermore, we classify all maximal orders in M2(F) over a valuation ring with value group Z m and in Mn(F) given a mild “defectless” assumption.
Tocopherol Metabolism Using Thermochemolysis: Chemical and Biological Properties of γ-Tocopherol, γ-Carboxyethyl-hydroxychroman, and Their Quinones

Identification and quantitative estimation of quinone metabolites of γ-tocopherol (γ-T) and its derivative γ-carboxyethyl hydroxychroman (γ-CEHC) are complicated by their functions as arylating electrophiles. We hypothesize that their biological properties are expressed through arylating quinone electrophile addition (Michael reaction) with thiol nucleophiles in cells and tissues. Glutathione (GSH) reacted with γ-tocopheryl quinone (γ-TQ) to form the hydroquinone adduct, which was identified by electrospray time-of-flight MS (ESI-TOF-MS). Tetramethylammonium hydroxide (TMAH) thermochemolysis reduced and methylated quinones and cleaved and methylated thioether adducts. These relatively nonpolar derivatives were readily separated by GC and identified by MS fragmentation patterns. γ-CEHC was synthesized and oxidized to a product identified as the quinone lactone (γ-CEHC-QL). TMAH methylated both γ-CEHC-QL and its GSH adduct without opening the lactone ring, and these products were separated by GC and identif...
Effects of testosterone upon MPTP-induced neurotoxicity of the nigrostriatal dopaminergic system of C57/B1 mice

Abstract We have recently reported that treatment of gonadectomized female and male C57/B1 mice with the gonadal steroid hormone, estrogen, reduced nigrostriatal dopaminergic neurotoxicity resulting from the Parkinson's-like inducing agent 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine (MPTP). In the present report we examined whether the predominantly male gonadal steroid hormone, testosterone, would similarly modulate MPTP-induced neurotoxicity. Male C57/B1 mice were assigned to one of the following five treatment conditions: (1) Intact, (2) Orchidectomized, (3) Intact + MPTP, (4) Orchidectomized + Testosterone + MPTP and (5) Orchidectomized + MPTP. Corpus striatal and olfactory tubercle dopamine, DOP AC and norepinephrine concentrations were determined from the animals within each of the five treatment conditions. Orchidectomy alone failed to alter striatal dopamine and DOPAC concentrations, with levels obtained being similar to that of Intact animals. MPTP treatment significantly reduced striatal dopamine and DOPAC concentrations, regardless of hormonal condition of the animal. Similar results were obtained for olfactory tubercle determinations, with the exception that DOPAC levels from Orchidectomized mice were significantly greater than Intact males. No significant differences were obtained for norepinephrine within either brain area sampled. These results show that unlike estrogen, testosterone is devoid of any capacity to modulate nigrostriatal dopaminergic neurotoxicity resulting from MPTP. These findings may be related to the gender differences which exist in the prevalence of Parkinson's disease.
Cardiopulmonary cerebral resuscitation in neonatal foals

Abstract Cardiovascular or pulmonary system failure in neonatal foals requires rapid recognition and initiation of cardiopulmonary cerebral resuscitation (CPCR). Foals may require resuscitation immediately after birth or after arrest from progression of a disease process such as severe sepsis or septic shock. Initial treatment is aimed at establishing an airway and providing ventilation. Circulation is provided by closed-chest compressions. Circulatory access is important to provide intravenous fluid and pharmacologic therapy for cardiovascular support. Ventricular fibrillation and pulseless ventricular tachycardia are arrhythmias not commonly recognized with arrest in foals, whereas asystole and cardiovascular collapse are frequently encountered. Training of personnel, preparation of supplies, and organization during CPCR is essential to a successful outcome. Most of the information used for CPCR in neonatal foals is derived from human medical research and clinical medicine. As new advances are made in human neonatal and pediatric CPCR, many of these treatments and techniques can be applied to foals. This article reviews currently available CPCR guidelines in foals and highlights new perspectives in human medicine that may be applicable to foals.
First Isolation of West Nile virus from a patient with encephalitis in the United States.

West Nile virus (WNV) was isolated from a patient who developed encephalitis while undergoing treatment with CHOP (cyclophosphamide, hydroxydoxorubicin, vincristine [Oncovin], predisone) and rituximab for a non-Hodgkin B-cell lymphoma. Both standard reverse transcription–polymerase chain reaction (RT-PCR) and Taqman RT-PCR established the diagnosis of WNV infection from cerebrospinal fluid (CSF). Several whole blood samples and one serum sample underwent further testing. CSF and serum samples were negative for WNV antibody; however, all samples were positive by both RT-PCR assays. Infectious virus was recovered from a blood sample, and its identity was confirmed by using a WNV-specific immunofluorescence assay. The complete WNV genomes determined from CSF and from the virus isolate adapted from cell culture were the same. The results represent the first complete WNV genome sequence obtained directly from human CSF and the first time that infectious WNV has been recovered from a patient with encephalitis in North America. est Nile virus (WNV), an arthropod-borne virus, is a member of the Japanese encephalitis virus serocomplex of the genus Flavivirus, family Flaviviridae (1), discovered in Uganda in 1937 (2). Although WNV infections are usually mild or asymptomatic, in some instances, a severe and fatal encephalitis is produced, typically in the elderly (3). This virus was first recognized in the Western Hemisphere in an outbreak in New York in 1999 (4). As of October 2, 2002, a total of 2.671 cases of human illness in the United States have been reported to the Centers for Disease Control and Prevention (CDC). Although WNV has been recovered from mosquitoes, birds, and horses, no isolations from humans have been reported in the Western Hemisphere. Thus, all prior data regarding the virus responsible for human illness in North America have come from nucleic acid sequencing of the viral genome in either cerebrospinal fluid (CSF) or brain tissue. We describe the first isolation of WNV from a human case-patient associated with the U.S. outbreak. Because the virus was also directly detected by reverse transcription–polymerase chain reaction (RT-PCR) in specimens from the same patient, we were able to compare the entire genomic sequence of the directly detected virus with that of the cell-culture isolate. Case Report
First principles calculation of optical and electronic properties with inclusion of exciton effects

First principles theory and methodology have made rapid advances in their ability to describe electronic excitations and optical properties from first principles. Here we present an overview of the progress in this field. We illustrate with results for three systems that exhibit interesting excitonic behavior: single-walled carbon nanotubes, single-walled gallium nitride nanotubes, and self-trapped excitons in silica. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Unsplittable Flow in Paths and Trees and Column-Restricted Packing Integer Programs

We consider the unsplittable flow problem (UFP) and the closely related column-restricted packing integer programs (CPIPs). In UFP we are given an edge-capacitated graph G = (V ,E ) and k request pairs R 1 , ..., R k , where each R i consists of a source-destination pair (s i ,t i ), a demand d i and a weight w i . The goal is to find a maximum weight subset of requests that can be routed unsplittably in G . Most previous work on UFP has focused on the no-bottleneck case in which the maximum demand of the requests is at most the smallest edge capacity. Inspired by the recent work of Bansal et al . [3] on UFP on a path without the above assumption, we consider UFP on paths as well as trees. We give a simple O (logn ) approximation for UFP on trees when all weights are identical; this yields an O (log2 n ) approximation for the weighted case. These are the first non-trivial approximations for UFP on trees. We develop an LP relaxation for UFP on paths that has an integrality gap of O (log2 n ); previously there was no relaxation with o (n ) gap. We also consider UFP in general graphs and CPIPs without the no-bottleneck assumption and obtain new and useful results.
A documentation-related approach to object-oriented program understanding

Object-oriented code is considered to be inherently more reusable than functional decomposition code; however, object-oriented code can suffer from a program understanding standpoint since good object-oriented style seems to require a large number of small methods. Hence code for a particular task may be scattered widely. Thus good semantics based tools are necessary. This paper describes an approach to object-oriented code understanding that focuses largely on informal linguistic aspects of code, such as comments and identifiers. >
Hippocampal shape analysis: surface-based representation and classification

Surface-based representation and classiflcation techniques are studied for hippocampal shape analysis. The goal is twofold: (1) develop a new framework of salient feature extraction and accurate classiflcation for 3D shape data; (2) detect hippocampal abnormalities in schizophrenia using this technique. A flne-scale spherical harmonic expansion is employed to describe a closed 3D surface object. The expansion can then easily be transformed to extract only shape information (i.e., excluding translation, rotation, and scaling) and create a shape descriptor comparable across difierent individuals. This representation captures shape features and is ∞exible enough to do shape modeling, identify statistical group difierences, and generate similar synthetic shapes. Principal component analysis is used to extract a small number of independent features from high dimensional shape descriptors, and Fisher’s linear discriminant is applied for pattern classiflcation. This framework is shown to be able to perform well in distinguishing clear group difierences as well as small and noisy group difierences using simulated shape data. In addition, the application of this technique to real data indicates that group shape difierences exist in hippocampi between healthy controls and schizophrenic patients.
Combining statistics and semantics via ensemble model for document clustering

Incorporating background knowledge into data mining algorithms is an important but challenging problem. Current approaches in semi-supervised learning require explicit knowledge provided by domain experts, knowledge specific to the particular data set. In this study, we propose an ensemble model that couples two sources of information: statistics information that is derived from the data set, and sense information retrieved from WordNet that is used to build a semantic binary model. We evaluated the efficacy of using our combined ensemble model on the Reuters-21578 and 20newsgroups data sets.
Students’ images and their understanding of definitions of the limit of a sequence

There are many studies on the role of images in understanding the concept of limit. However, relatively few studies have been conducted on how students’ understanding of the rigorous definition of limit is influenced by the images of limit that the students have constructed through their previous learning. This study explored how calculus students’ images of the limit of a sequence influence their understanding of definitions of the limit of a sequence. In a series of task-based interviews, students evaluated the propriety of statements describing the convergence of sequences through a specially designed hands-on activity, called the ɛ–strip activity. This paper illustrates how these students’ understanding of definitions of the limit of a sequence was influenced by their images of limits as asymptotes, cluster points, or true limit points. The implications of this study for teaching and learning the concept of limit, as well as on research in mathematics education, are also discussed.
Estimating mental stress using a wearable cardio-respiratory sensor

This article describes a signal-processing approach to detect mental stress using unobtrusive wearable sensors. The approach addresses a major weakness of traditional methods based on heart-rate-variability (HRV) analysis: sensitivity to respiratory influences. To address this issue, we build a linear model that predicts the effect of breathing on the autonomic nervous system activation, as measured through HRV. Subtraction of respiratory effects leads to a residual signal that provides better discrimination between mental stress and relaxation conditions than traditional HRV tachogram. The method is experimentally validated on a discrimination task with two psycho-physiological conditions: mental stress and relaxation. To illustrate the effectiveness of the method, we impose a pacing respiratory signal that interferes with the main spectral band of the sympathetic branch. Our results suggest that the HRV residual signal has more discrimination power than conventional HRV analysis in the presence of respiration interferences.
A low-power chipset for a portable multimedia I/O terminal

This paper presents the design of a low-power chipset for a portable multimedia terminal that supports pen input, speech I/O, text/graphics output, and one-way full-motion video. Its power consumption was minimized using an approach that involves optimization at all levels of the design, including extended voltage scaling, reduced swing logic, and switched capacitance reduction through operation reduction, choice of number representation, exploitation of signal correlations, self-timing to eliminate glitching, logic design, circuit design, and physical design. The entire chipset, which performs protocol conversion, synchronization, error correction, packetization, buffering, video decompression, and D/A conversion, is implemented in 1.2 /spl mu/m CMOS and operates from a 1.1 V supply while consuming less than 5 mW. >
Stability analysis of rotational Couette flow of stratified fluids

A linear stability analysis is used to investigate the stability of rotational Couette flow of sbratified fluids. The linearized time-dependent perturbation equations are solved using explicit finite-difference approximations. Small random axisymmetric perturbations of a given wavelength are initially distributed in the flow field, and their development in time is obtained by numerical integration. It is found that the kinetic energy of the perturbations oscillates in time owing to the periodic transformation of the disturbance flow field from a one-vortex system to a two-vortex system and vice versa. The neutral condition is defined as the state in which the maxima of the perturbation kinetic energy curve no longer change in time. A neutral-stability curve is obtained using the experimentally observed critical wavelengths. It is in general agreement with the experimental data, and it confirms the experimental result that stable density stratification enhances stability.
Methamphetamine Use, Self-Reported Violent Crime, and Recidivism Among Offenders in California Who Abuse Substances

This study uses data from 641 state prison parolees in California to examine the associations between methamphetamine use and three measures of criminal behavior: (a) self-reported violent criminal behavior, (b) return to prison for a violent offense, and (c) return to prison for any reason during the first 12 months of parole. Methamphetamine use was significantly predictive of self-reported violent criminal behavior and general recidivism (i.e., a return to custody for any reason). However, methamphetamine use was not significantly predictive of being returned to custody for a violent offense. These trends remained even after controlling for involvement in the drug trade (i.e., sales, distribution, or manufacturing).
Caspase-3-Dependent and -Independent Apoptosis in Focal Brain Ischemia

Although extensive caspase-3 activation has been demonstrated in experimental brain ischemia produced in neonatal rat, the role this caspase plays in the focal ischemia of adult brain is not clear, as the levels of caspase-3 in adult rat brain are extremely low. This raises the question whether caspase-3 synthesis and activation are essential for execution of the apoptotic program and DNA fragmentation in permanent brain ischemia, a condition that impairs cellular protein synthesis. Rat middle cerebral artery was permanently occluded and histochemical detection of procaspase-3, active caspase-3 and DFF40/CAD and apoptotic morphology analysis were performed at 6, 24, 48, and 72 hours after occlusion. Necrosis and two types of programmed cell death (PCD) are identified in this study of permanent focal brain ischemia. The first type of PCD is represented by active caspase-3 and DFF40/CAD-positive cells. The second type of PCD is represented by caspase-3 and DFF40/CAD negative cells, which display morphological signs of apoptosis-like PCD: namely, nuclear chromatin condensation in lump masses and apoptotic body formation. The cells of the first type have a maximum number noted after 24 hours of ischemia. The cells of the second type are primarily seen after 48 and 72 hours of ischemia. Necrotic cells, which are also detected in the stroke, are caspase-3 negative, and have swollen nuclei, without chromatin condensation and apoptotic body formation. Our results indicate that in permanent brain ischemia in adult rats, PCD processes occur differently in various parts of ischemic zone. In conditions of severe energy depletion, the reactions of cellular disassembly and packaging into apoptotic bodies are accomplished without either caspase-3 expression or the activation of caspase-3-dependent deoxyribonuclease.
Photonic Transistors based on Gain and Absorption Manipulation of Optical Interference

A novel semiconductor photonic transistor employing gain and absorption manipulation of optical interference is proposed. These devices could have a transistor figure of merits >105 times higher than chi(3) approaches and are highly attractive.