cssi/SciSciGPT-SciSciNet huggingface dataset:
Fiber and interface fracture in singlecrystal aluminum/SiC fiber composites

Model metal-matrix composite tensile specimens, each containing a single SiC fiber in a single crystal of pure Al, were grown using a modified Bridgman method at two growth rates and with various fiber surface treatments in order to study their effect on fiber and interface strength. Using the load drops in tensile tests, we measured both fiber and interface strengthin situ. Acoustic emission (AE) was monitored to assist in determining the failure mechanisms. Both the fiber surface treatment and growth rate were found to significantly affect the fiber and interface strength. Fibers with carbon-rich outer surfaces had higher fiber strengths but lower interfacial strengths than untreated fibers. These results are discussed in terms of failure mechanisms and interfacial reactions occurring during growth of the composites.
Bridge toughening enhancement in double-notched MoSi2/Nb model composites

Single-ply composites containing both laminate and continuous Nb fiber reinforcement coated with A12O3 debond coatings in an MoSi2 matrix are used as model systems for investigating bridge toughening concepts for various precrack configurations. When cracks are introduced symmetrically on either side of the ductile phase with zero crack offset spacing (S = 0), a minimum amount of energy is expended in plastic deformation and the local rupture process in the metal, as measured by the area of the force displacement curve in tension. For asymmetric precracks introduced on either side of the ductile reinforcement, as the offset spacing,S, was varied from 1 to 20R (R being the ductile phase half-thickness), the overall extension continuously increased within the bridging ligament. The effective ligament gage length was nearly equal to the crack spacing in the limiting case of a weak interface. However, the ductile Nb phase developed a Nb5Si3 reaction layer on its surface which was strongly bonded to the Nb and was found to undergo periodic cracking, leading to numerous shear bands within the ductile phase. This unique and previously unreported mode of metal deformation in shear loading has been analyzed using a simple geometric model. The results indicate that the profusion of shear bands is the primary source of toughening enhancement in the case of asymmetric crack geometry, which was not recognized in prior work of this type.
A spectral model for estimating temporal and spatial evolution of rippled seabeds

Existing time variable ripple prediction models have focused on ripple wavelength and height yet have not accounted for the effect of wave directionality on ripple evolution. These models use an equilibrium ripple sub-module that provides the target geometry of the seabed. Temporal variability of the hydrodynamic conditions cause ripple geometry to lag behind and not always agree with that predicted by equilibrium models. In this contribution, previous work is extended through the development of a new 2-D, time variable, spectral ripple model that allows for the estimation of ripple wavelength, height, and orientation. Since ripple irregularity is associated with directionality, the new model also has the ability to predict the irregularity of the rippled seabed. A comparison of the 2-D and existing time-dependent models is carried out using both synthetic and field ripple data that consist of time series representing a variety of wave-forcing conditions. Under strong wave forcing with no orientation changes, the 2-D model predicts ripple wavelength and orientations that agree with those of existing models. During periods of change in wave directions, the 2-D model predicts a significantly smaller ripple height during ripple reorientation. Under weaker energy flows, the 2-D model yields improved estimates especially for relict ripple geometry. In addition, the 2-D model’s spectrum yields a prediction of the seabed irregularity.
Construction of the granitoid crust of an island arc. Part II: a quantitative petrogenetic model

Results of simple model calculations that integrate cumulate compositions from the Kohistan arc terrain are presented in order to develop a consistent petrogenetic model to explain the Kohistan island arc granitoids. The model allows a quantitative approximation of the possible relative roles of fractional crystallization and assimilation to explain the silica-rich upper crust composition of oceanic arcs. Depending in detail on the parental magma composition hydrous moderate-to-high pressure fractional crystallization in the lower crust/upper mantle is an adequate upper continental crust forming mechanism in terms of volume and compositions. Accordingly, assimilation and partial melting in the lower crust is not per se a necessary process to explain island arc granitoids. However, deriving few percent of melts using low degree of dehydration melting is a crucial process to produce volumetrically important amounts of upper continental crust from silica-poorer parental magmas. Even though the model can explain the silica-rich upper crustal composition of the Kohistan, the fractionation model does not predict the accepted composition of the bulk continental crust. This finding supports the idea that additional crustal refining mechanism (e.g., delamination of lower crustal rocks) and/or non-cogenetic magmatic process were critical to create the bulk continental crust composition.
Effect of stereoconfiguration on ripple phases (Pβ′) of dipalmitoylphosphatidylcholine

Abstract Mixtures of sn -1 ( d ) and sn -3 ( l ) enantiomers of fully hydrated dipalmitoylphosphatidylcholine (DPPC) were studied with differential scanning calorimetry and freeze-fracture microscopy. The pretransition temperature of racemic mixtures of DPPC was 1.8 C° below that of either pure sn -1 or sn -3 enantiomers, which had similar pretransition temperatures. The main transition temperature of racemic mixtures was also depressed, but to a lesser extent, 0.8 C°. Freeze-fracture images of liposomes of sn -1, sn -3, and racemic mixtures of DPPC frozen from the P β′ phase showed well-defined ripples of wavelength 13 nm. Lipid stereoconfiguration had no effect on ripple wavelength, configuration or amplitude, or on the number and nature of surface defects.
Neurotrophins and the anti-inflammatory agents interleukin-4 (IL-4), IL-10, IL-11 and transforming growth factor-β1 (TGF-β1) down-regulate T cell costimulatory molecules B7 and CD40 on cultured rat microglia

Microglia are essential for T cell activation in the CNS. Since T cell activation requires costimulation by B7 and/or CD40, we examined the regulation by cytokines of B7-1, B7-2 and CD40 mRNA expression in cultured rat microglia in serum-free medium. All three ligands are expressed constitutively, but are profoundly up-regulated by granulocyte-macrophage colony-stimulating factor (GM-CSF). By contrast, interferon-gamma raises only B7-2 and CD40 mRNA, and the B7-2 increase is inhibited by IL-10. IL-4, transforming growth factor-beta1, and nerve growth factor (NGF) repress GM-CSF-induced B7-2 and CD40, but not B7-1. NGF also down-regulates its own high-affinity trkA receptor. IL-11, unrecognized for its effect on antigen presentation, represses GM-CSF-induced B7-2.
Community‐level consequences of mycorrhizae depend on phosphorus availability

In grasslands, arbuscular mycorrhizal fungi (AMF) mediate plant diversity; whether AMF increase or decrease diversity depends on the relative mycotrophy in dominant vs. subordinate plants. In this study we investigated whether soil nutrient levels also influence the ability of AMF to mediate plant species coexistence. First, we developed a conceptual model that predicts the influence of AMF on diversity along a soil nutrient gradient for plant communities dominated by mycotrophic and non-mycotrophic species. To test these predictions, we manipulated phosphorus to create a soil nutrient gradient for mesocosm communities composed of native prairie grasses and then compared community properties for mesocosms with and without AMF. We found that, where P was limiting, AMF increased plant diversity and productivity, and also altered community structure; however, at high P, AMF had little influence on aboveground communities. Compositional differences among treatments were due largely to a trade-off in the relative abundance of C3 vs. C4 spes. Our study emphasizes how environmental constraints on mutualisms may govern community- and ecosystem-level properties.
Wavelength effects on simple reaction time

Simple reaction time was measured to spectral lights matched photometrically in luminance. When these lights were presented on a dimmer achromatic background, reaction time did not vary as a function of wavelength. Moreover, reaction times to white and chromatic lights were the same. When the luminance of the background was the same as that of the chromatic lights, reaction time increased and showed a strong effect of wavelength. Reaction time in this condition appeared to follow a saturation function. The results are described in terms of the operation of achromatic and chromatic processing channels.
FUNCTIONAL SIMILARITIES OF SPIDER WEBS WITH DIVERSE ARCHITECTURES

Spider orb webs are made of sticky prey capture threads supported by a scaffold of nonsticky threads. Capture threads produced by members of the family Uloboridae are formed of thousands of dry, proteinaceous silk fibrils. From measurements of the diameters and lengths of fibers that form the sticky and nonsticky threads of uloborids, this study determines the volume of silk these webs contain. It employs a transformational analysis to examine the relationship between spider size and the silk volume and total stickiness of webs produced by four orb-weaving species and four species that spin simpler webs. Despite differences in web design, web-monitoring behavior, and spider size, a web's total silk volume is directly related to spider weight. A web's prey capture potential, as determined by its total stickiness and total capture area, is also directly related to spider weight. The volume of silk fibrils responsible for a web's stickiness is related to spider weight, whereas the volume of its support eleme...
Feedback regulation of murine Ly‐1 B cell development

Studies presented here, conducted with allotype homozygotes, demonstrate the existence of a feedback mechanism that regulates development of Ly-1 B cells from immature progenitors. In the preceding study (P. A. Lalor et al., Eur. J. Immunol. 1989. 19: 501), conducted with allotype heterozygotes, we showed that treating neonates with monoclonal antibody to the paternal allotype IgM depletes roughly half of the neonatal B cell population (i.e. those expressing the paternal IgM allotype) and that paternal allotype Ly-1 B cells specificically remain depleted for the life of the animal. Here we show that treating allotype homozygotes with the same antibody depletes all (rather than half) of the B cells and that, under these conditions, relatively normal numbers of Ly-1 B cells reappear shortly after the treatment antibody disappears. This recovery, we also show, is prevented by restoring allotype-congenic Ly-1 B cells to the treated homozygotes, i.e. by reconstituting treated neonates with allotype-congenic peritoneal cells, sorted Ly-1 B cells or a monoclonal population of Ly-1 B “tumor” cells. These findings in essence reveal a feedback mechanism through which mature Ly-1 B cells prevent further Ly-1 B cell development from Ig- precursors. This feedback regulation is independent of Ig secretion by the mature Ly-1 B cells, since the monoclonal Ly-1 B “tumor” population that prevents endogenous Ly-1 B development does not secrete Ig. Furthermore, it appears to be independent of Ly-1 B surface Ig specificity, since a monoclonal population is sufficient to block all Ly-1 B cell development. This mechanism appears to operate normally to fix the composition of the Ly-1 B population, which survives through self-replenishment in adults, in accord with conditions that influence Ly-1 B development during neonatal life.
X-ray absorption, emission, and resonant inelastic scattering in solids.

The process of x-ray absorption and emission in solids is considered as an x-ray resonant inelastic scattering process. This coherent inelastic scattering picture has recently been used to interpret the excitation energy dependence in the x-ray emission spectra excited with synchrotron radiation. It also suggests that with near threshold excitation, the x-ray emission spectra should be spatially anisotropic. We consider the validity and implication of this approach and factors affecting the spatial and temporal coherence in the scattering process. Taking into account the relaxation effects such as the electron-electron and the electron-phonon interactions, a significant fraction of the total emission intensity may be attributed to the coherent scattering. This picture of the x-ray absorption and emission process opens up the possibility for momentum-resolved x-ray absorption and emission measurements that can be used for band-structure determination. In addition, it has important implications on the fluorescence yield method of obtaining the absorption spectra.
Stimuli-reponsive polymers and their bioconjugates

Abstract Stimuli responsive polymers can provide a variety of applications for the biomedical fields. The interest in these polymers has exponentially increased due to their promising potential. Among them, temperature and pH responsive mechanisms have been considerably investigated because they are relatively convenient and effective stimuli in many applications. In this review, our main purposes are focused on temperature and pH responsive polymer systems and additionally the other stimuli-based responsive polymers will be assessed. Dozens of reviews have been recently reported to introduce the field of stimuli responsive polymers. However, most of these reviews have been focused on one specific application such as drug delivery or one specific physical form such as hydrogels. In our point of view, the whole range of applications and physical forms of stimuli responsive polymers will be elucidated, which is more helpful to design new approaches because the basic concepts and mechanisms are systematically connected. This means that any new advanced concepts and mechanisms can be utilized in a variety of other applications as well as other physical forms. Also, we will describe the classification of stimuli responsive polymers by their mechanism of response to stimuli. Moreover, this review focuses on recent approaches of molecular designs which are extremely necessary to develop more desirable and functional stimuli responsive polymers.
A Pivotal Voter from a Pivotal State: Roger Sherman at the Constitutional Convention

Robertson (2005) and Rakove (1996) argue that Roger Sherman was surprisingly influential at the Constitutional Convention. Using empirically estimated ideal points, we show that Sherman was a pivotal voter from a pivotal state. We also demonstrate that if the votes were tallied by individual delegates, rather than being grouped by the home state, then Sherman would have been less pivotal. This suggests that the voting procedures adopted at the Constitutional Convention may have affected Sherman's ability to get his interests enacted. Such institutions might have been more responsible than his legislative ability for making Sherman effective.
The coroutine model of computation

This paper presents a general denotational formalism called the Coroutine Model of Computation for control-oriented computational models. This formalism characterizes atomic elements with control behavior as Continuation Actors, giving them a static semantics with a functional interface. Coroutine Models are then defined as networks of Continuation Actors, representing a set of control locations between which control traverses during execution. This paper gives both a strict and non-strict denotational semantics for Coroutine Models in terms of compositions of Continuation Actors and their interfaces. In the strict form, the traversal of control locations forms a control path producing output values, whereas in the non-strict form, execution traverses a tree of potential control locations producing partial information about output values. Furthermore, the given non-strict form of these semantics is claimed to have useful monotonicity properties.
Fibroproliferative neuromas may occur after iatrogenic injury for lipomatosis of nerve.

BACKGROUND Lipomatosis of nerve (LN) is a condition associated with nerve-territory overgrowth. We have noted a unique type of neuroma at sites of LN injury; the neuroma extends beyond the epineurium, enhances, and appears to enlarge over time. OBJECTIVE We sought to understand the relationship between fibroproliferative scarring and surgery performed on the nerve. METHODS A review of the searchable records for LN at our institution found 52 cases, confirmed by pathology or pathognomonic appearance on magnetic resonance imaging (MRI). Clinical histories were reviewed to categorize the surgeries performed by the degree of iatrogenic injury to the nerve. Postoperative MRI was performed in 22 of the 46 patients who had surgery, which was then retrospectively reviewed for fibroproliferative neuromas. RESULTS Complex and masslike neuromas were found on MRI, correlating with the degree of iatrogenic injury to the nerve. These fibrous neuromas proliferated beyond the epineurium, disrupted fascicular architecture, were contrast enhancing when contrast was administered, indicative they were unique and unlike stump or traction neuromas. Of the 8 patients who underwent surgery involving nerve decompression alone, none developed fibroproliferative neuromas. Of the 7 patients who underwent surgery involving nerve debulking, fibroproliferative neuromas developed in 4. Of the 11 patients who underwent surgery involving nerve transection, all developed fibroproliferative neuromas (P < .001). There was also a high incidence of hypertrophic scarring of the skin incision (21.3%). CONCLUSION Surgical injury of LN appears to be strongly associated with the development of fibroproliferative neuromas. It is possible that the pathological overgrowth stimulus associated with LN promotes exuberant scar formation.
Structure tailoring of alkoxide silica

Abstract This study examines the influence of pH in the starting sol on the structure of alkoxide derived silica. The relative rates of hydrolysis and condensation of the alkoxide were altered by pH which yielded materials with different microstructure, stability and sintering behavior. Structural evolution of alkoxide silica during densification was followed in situ by photoacoustic Fourier-transform infrared spectroscopy (PAS). The acid-catalyzed silica gels contained a larger amount of adsorbed water and alcohol than the base-catalyzed gels/precipitates. Hydrogen-bonded surface species in acid-catalyzed gels were removed easily, allowing this material to be densified at 800°C. Although base-catalyzed gels had less hydrogenbonded silanol groups in the green state, it consisted of free silanol groups which maintained a high gel surface area and indicated little sintering below 1000°C.
Correlation of heterozygosity and the number of alleles in different frequency classes

Abstract Analytic expressions for the expectations and variance of the number of alleles with gene frequencies in a specified class are derived in the entire population as well as in a random sample of genes drawn from the population. The correlation of this quantity with heterozygosity at the locus is also obtained. The derivations are given in details for a steady state population of finite size under the infinite allele model of selectively neutral alleles. The results are extended to include weak selection pressures and non-stationarity of the population. The relevance of the correlation of heterozygosity and the number of rare alleles in connection with the neutralist-selectionist controversy is also discussed.
Trends in the AIDS epidemic among New York City's injection drug users: localized or citywide?

The New York City injection drug user acquired immunodeficiency syndrome (IDU AIDS)epidemic accounts for almost one quarter of AIDS cases in IDUs in the United States. Recent studies have reported declines in seroprevalence and risk behaviors among IDUs in New York City during the 1990s. These trends, however, are based on studies primarily conducted in the city’s central borough of Manhattan. This article analyzes data from all five boroughs of New York City to examine trends over phases of the epidemic and to determine the level of prevention services available; an exploratory qualitative study was also conducted to assess access to prevention services and injection practices in areas in the “outer boroughs”. Findings indicated that (1)borough differences in services and behaviors existed from early in the epidemic; (2)services have been concentrated in Manhattan; and (3)declines in seroprevalence were greatest among Manhattan-recruited IDUs. Enhancing access to services for IDUs in the boroughs outside Manhattan may be needed to continue the positive trends in all areas of New York City.
Body Consciousness Across the Adult Years: Variations with Actual and Subjective Age

Age-related trends and predictors were explored with respect to three dimensions of adults’ body consciousness. Consistent with the notion that aging adults’ perceptions of their bodies are multidimensional and multidirectional, adults reported being more concerned about their external physical appearance (public body consciousness), more aware of their internal body sensations (private body consciousness), and more positive in their self-evaluations of their bodies (body competence). Moreover, consistent with the claim that such attitudes are multi-determined, the present research found that aging adults’ personal anxiety about aging and their subjective age identities were significant predictors of variations in their body consciousness. Moreover, the predictive value of these psychological variables rivaled the predictive value of chronological age.
Damage detection of carbon fiber reinforced polymer composites via electrical resistance measurement

Abstract Carbon fiber reinforced polymer–matrix composites (CFRPs) are widely applicable in various important structural components. One of the critical issues in the successful application of CFRPs is the assessment of damage state in a particular structural component. Electrical resistance measurement is a merging non-destructive evaluation technology for real-time/on-board damage detection in CFRPs. This paper overviews the recent advances in damage detection in CFRPs using the resistance measurement. Besides the discussions on various experimental methods for self-sensing and damage detection, modeling from microscale to continuum levels for the predictions of resistances change due to the mechanical damages are also presented. Future directions in damage detection of CFRPs using the resistance method are provided.
Ultrasensivite three dimensional nanoscale chemical imaging

We demonstrate nano-scale 3-dimensional chemical imaging by extreme ultraviolet laser with 75 nm lateral, 20 nm depth resolution, and 0.01 aM sensitivity. 3D composition images of a single micro-organisms were obtained.
Anatomic study of the collateral blood supply of the sternum

A microdissection study was carried out on ten injected, cleared human sternal specimens. Three types of vessel were identified that have the potential to carry blood to the sternum after mobilization of the internal thoracic artery (ITA): (1) branches of the ITA that supply both the sternum and the pectoralis major ("sternal/perforating branches"), (2) branches of the ITA that supply both the sternum and an adjoining intercostal space ("sternal/ intercostal branches"), and (3) posterior intercostal arteries that do not anastomose with an ITA branch but continue past the ITA to reach the sternum. All three types of vessel were found more frequently in the proximal than in the distal half of the sternum. For sternal/ perforating and sternal/intercostal vessels to function as collaterals after ITA bypass grafting, their short common trunks of origin must remain intact. The data support the recommendation that the branches of the ITA be ligated as close as possible to the ITA itself to preserve collateral blood flow to the sternum.
Internal conversion and energy transfer dynamics of spheroidene in solution and in the LH-1 and LH-2 light-harvesting complexes

Abstract Femtosecond time resolved fluorescence upconversion was applied to determine directly the lifetime of the 1B u + state of the carotenoid spheroidene in vitro in various polar and nonpolar solvents and in the LH-1 and LH-2 light-harvesting complexes of Rhodobacter sphaeroides at room temperature. The spheroidene 1B u + → 2A g − internal conversion time varies from 150 to 250 fs in the solvents studied and depends on the polarizability of the surrounding environment. The internal conversion time in the protein environment is estimated based on the solution measurements. There is a dramatic shortening for the spheroidene 1B u + fluorescence lifetime seen inside LH-1 and LH-2 (60 fs and 80 fs, respectively) over this expected internal conversion time.
Confirming the Phylogeny of Mammals by Use of Large Comparative Sequence Data Sets

The ongoing generation of prodigious amounts of genomic sequence data from myriad vertebrates is providing unparalleled opportunities for establishing definitive phylogenetic relationships among species. The size and complexities of such comparative sequence data sets not only allow smaller and more difficult branches to be resolved but also present unique challenges, including large computational requirements and the negative consequences of systematic biases. To explore these issues and to clarify the phylogenetic relationships among mammals, we have analyzed a large data set of over 60 megabase pairs (Mb) of high-quality genomic sequence, which we generated from 41 mammals and 3 other vertebrates. All sequences are orthologous to a 1.9-Mb region of the human genome that encompasses the cystic fibrosis transmembrane conductance regulator gene (CFTR). To understand the characteristics and challenges associated with phylogenetic analyses of such a large data set, we partitioned the sequence data in several ways and utilized maximum likelihood, maximum parsimony, and Neighbor-Joining algorithms, implemented in parallel on Linux clusters. These studies yielded well-supported phylogenetic trees, largely confirming other recent molecular phylogenetic analyses. Our results provide support for rooting the placental mammal tree between Atlantogenata (Xenarthra and Afrotheria) and Boreoeutheria (Euarchontoglires and Laurasiatheria), illustrate the difficulty in resolving some branches even with large amounts of data (e.g., in the case of Laurasiatheria), and demonstrate the valuable role that very large comparative sequence data sets can play in refining our understanding of the evolutionary relationships of vertebrates.
SHORT-TERM MEMORY FOR COLORS AND COLOR NAMES

The Brown-Peterson paradigm was used to study the way colors and color names are encoded in memory. Three colored strips or the names of the 3 colors were presented on each of 4 trials. The 30-sec....
Learning Macro Actions from Instructional Videos Through Integration of Multiple Modalities

We propose an architecture for a system that will “watch and listen to” an instructional video of a human performing a task and translate the audio and video information into a task for a robot to perform. This enables the use of readily available instructional videos from the Internet to train robots to perform tasks instead of programming them. We implemented an operational prototype based on the architecture and showed it could “watch and listen to” two instructional videos on how to clean golf clubs and translate the audio and video information from the instructional video into tasks for a robot to perform. The key contributions of this architecture are: integration of multiple modalities using trees and pruning with filters; task decomposition into macro-tasks composed of parameterized task-primitives and other macro-tasks, where the task-primitive parameters are an action (e.g., dip, clean, dry) taken on an object (e.g., golf club) using a tool (e.g., pail of water, brush, towel); and context, for determining missing and implied task-primitive parameter values, as a set of canonical task-primitive parameter values with a confidence score based on the number of times the parameter value was detected in the video and audio information and how long ago it was detected.
Teaching physical activities to students with significant disabilities using video modeling

Objective: The objective of this study was to examine the effectiveness of video modeling on teaching physical activities to three adolescents with significant disabilities.Methods: The study implemented a multiple baseline across six physical activities (three per student): jumping rope, scooter board with cones, ladder drill (i.e. feet going in and out), ladder design (i.e. multiple steps), shuttle run, and disc ride. Additional prompt procedures (i.e. verbal, gestural, visual cues, and modeling) were implemented within the study. After the students mastered the physical activities, we tested to see if they would link the skills together (i.e. complete an obstacle course).Results: All three students made progress learning the physical activities, but only one learned them with video modeling alone (i.e. without error correction).Conclusion: Video modeling can be an effective tool for teaching students with significant disabilities various physical activities, though additional prompting procedures may b...
Exciton binding energies in GaN/AlxGa1 − xN pseudomorphic quantum wells

Abstract Interband transitions of pseudomorphic GaN/ Al x Ga 1 − x N quantum wells are analysed theoretically with respect to the piezoelectric field utilizing a 6 × 6 Rashba–Sheka–Pikus (RSP) Hamiltonian. Band structure modifications due to the built-in Stark effect explain a shift of the emission peak in GaN/ Al 0.15 Ga 0.85 N of up to 400 meV. Quantum well exciton binding energies are calculated by the variational method and are discussed in terms of spatial separation of electrons and holes by the built-in electric field, as well as the interaction between valence subbands.
EFFECTS OF REACTIVE OXYGEN SPECIES ON BRAIN SYNAPTIC PLASMA MEMBRANE CA2+-ATPASE

The regulation of free intracellular calcium [Ca2+]i is altered in neurons from the aged brain, possibly due to reductions in the activity of Ca2+ transporters. The plasma membrane Ca(2+)-ATPase (PMCA) plays a critical role in Ca2+ homeostasis, and its kinetic properties change in aged rat brain. These changes could be due to oxidative modification of PMCA as a result of age-related chronic oxidative stresses. The present studies were undertaken to determine the sensitivity of the neuronal PMCA to in vitro exposure of synaptic plasma membranes (SPMs) to reactive oxygen species (ROS). We examined the effects of three oxidants including peroxyl radicals generated by azo-initiators, 2,2'-Azobis 2-amidinopropane dihydrochloride (AAPH) and 4,4'-Azobis 14-cyanovaleric acid (ACVA), hydrogen peroxide (H2O2), and peroxynitrite (ONOO-). Synaptic plasma membranes briefly exposed to these oxidants were analyzed for functional and structural alterations in PMCA. Although all three oxidants led to significant loss of PMCA activity, the effect of ONOO- was the most potent, followed by peroxyl radicals and H2O2. Kinetic analysis of PMCA activity after oxidant treatment showed decreases in Vmax without significant changes in K(act). Immunoblots revealed oxidant-induced cross-linking of PMCA molecules that were partially reversed under reducing conditions and completely reversed with addition of urea. The PMCA appears to be very sensitive to inhibition by ROS and hence may be a target of oxidative stress in the aging brain. Reduction in its activity may contribute to age-related alterations in neuronal [Ca2+]i regulation.
Subjectivity in A computer‐assisted synoptic climatology I: Classification results

Numerous computer-assisted synoptic climatological classifications were performed to determine the validity of a commonly used ‘objective’ typing scheme. In this study, the correlation-based Kirchhofer technique was used to classify a large population of daily mean sea level pressure grids. Unlike previous methodological studies, metric parameters were held constant while the form of the data used in the classifications was varied. It is demonstrated that sample size, number of grid points and the particular random sample used will affect the classification results, thereby confirming previous work that has suggested that such typing schemes are extremely subjective. It is recommended that users of correlation-based techniques obtain a number of relatively large random samples of size n ≥ 1000 and perform several classification runs in order to reach an ‘optimum’ solution.
Preparation of fatty acid esters of polyol glucosides

Starch is readily converted into glucosides by heating with a polyol, such as propylene glycol or glycerol, for a short time at 125 C in the presence of a catalytic amount of sulfuric acid. The product resulting from the reaction of 3 or more moles of polyol per anhydroglucose unit consists mostly of polyol monoglucosides, which are quite resistant to degradation under alkaline interesterification conditions. Attempts to interesterify the glucosides under the usual conditions employed with fats and oils (methyl esters, 0.1% sodium hydroxide, and temperatures up to 200 C) produced no glucoside esters. However, interesterification proceeded readily at temperatures between 160 and 200 C when 5 to 10% soaps and hydrophilic esters (mixtures containing mono- and diglycerides or an ester of diethylene glycol monomethyl ether) were employed. Under pressures low enough to rapidly distill off the freed polyol or alcohol, most reactions could be completed in less than an hour. Good yields of glucoside esters were obtained with starch, glycerol, and fat when the required operations were conducted in sequence in one vessel without intermediate purifications.
Object Permanence in Five-and-a-Half-Month-Old Infants?

Event Set × Event Set designs were used to study the rotating screen paradigm introduced by Baillargeon, Spelke, and Wasserman (1985). In Experiment 1, 36 5 1/2-month-old infants were habituated to a screen rotating 180° with no block, a screen rotating 120° up to a block, or a screen rotating 180° up to and seemingly through a block. All infants were then tested on the same 3 events and also a screen rotating 120° with no block. The results indicate that infants are using novelty and familiarity preference to determine their looking times. To confirm this, in Experiment 2, 52 5 1/2-month-old infants were familiarized on either 3 or 7 trials to a screen rotating 180° with no block or a screen rotating 120° with no block. All infants were then tested on the same test events as in Experiment 1. Infants with fewer familiarization trials were more likely to prefer the familiar rotation event. The results of these 2 experiments indicate that infants did not use the possibility or impossibility of events but instead used familiarity or novelty relations between the habituation events and the test events to determine their looking times, and suggest that the Baillargeon et al. study should not be interpreted as indicating object permanence or solidity knowledge in young infants.
Design of a bidirectional MEMS actuator with high displacement resolution, large driving force and power-free latching

This paper describes the design and ANSYS modeling of a bidirectional thermal inchworm MEMS actuator featuring high actuation resolution (0.1µm) combined with large driving force (100mN) and power-free latching. A promising application of this device is for precision in-package positioning of optical fibers, but the actuator also has potential for wider use. The inchworm mechanism includes two E-shaped metallic actuators facing each other and a pusher between them that couples to a moveable object such as an optical fiber. Nickel is chosen as the material of the actuators due to its desirable electrical, thermal, and mechanical properties, and availability in fabrication facilities. Electrothermal actuation is used to move the pusher as well as the optical fiber in the desired direction by inputting electric currents in a particular sequence. A transient thermal-mechanical analysis shows the feasibility of the input sequence that drives the inchworm actuation.
Normal pupil findings can give a false sense of security in a presumed cranial nerve III palsy patient: A unique case report.

Abstract Background A cranial nerve (CN) III palsy can be caused by a life-threatening aneurysm, typically of the posterior communicating artery. The “rule of the pupil” states the majority (96%) of such cases will present with abnormal pupil findings caused by compression of the fibers, located superficially along CN III. Careful examination of the size and reactivity of the pupils is critical. Case Report This case describes the complex management of a 79-year-old man with sudden-onset ptosis and diplopia consistent with a superior division CN III palsy. The pupils were normal, but because of the incomplete nature of the palsy the “rule of the pupil” could not be applied, and an aneurysm remained a threat. After urgent testing, microvascular infarct was deemed the cause. However, the palsy failed to resolve after 3 months. Further investigation found myasthenia gravis as the final diagnosis. Conclusions Several important points are outlined regarding CN III palsies. First, lack of pupil involvement in an incomplete palsy is not equivalent to pupil sparing in a complete palsy. Second, after initial diagnosis, if subsequent findings are no longer consistent, further investigation is warranted. Lastly, myasthenia gravis should be considered as a differential in apparent palsy cases.
Cellular interactions as a response to injury in the organ of corti in culture

We discovered and described ultrastructurally the intricate relationships between the sensory cells and their supporting cells in cultures of the organ of Corti following laser beam irradiation. Injury was performed using a 440 nm nitrogen-dye pulse laser aimed at the cuticular plates of inner hair cells. Laser injury is compared with mechanical injury inflicted on the hair cell region by a pulled-glass pipette. Regardless of the type of injury, but depending on its severity, the surviving hair cells may: (1) lose their stereocilia but subsist at the surface of the organ; (2) retain contact with the reticular lamina but be overgrown by the processes of the supporting cells; or (3) become sequestered from the reticular lamina and internalized among the supporting cells, where they either remain dedifferentiated or regrow an apical process which regains contact with the surface of the organ. All supporting cells, including pillar and Deiters cells take part in wrapping their respective inner or outer hair cells. The supporting cells not only cover the injured sensory cells, but also invert their villi toward the maimed cuticular plates and release an extracellular matrix around them. We suggest that the supporting cells play a protective and trophic role in the recovery of injured hair cells.
Earthquake and Earth deformation

Geophysicists are cognizant, if not in fear, of the chances of one or more great earthquakes occurring in the United States during the next several to 100 years. The San Andreas fault is, of course, the major threat. The worst earthquake along it occurred in 1857 in southern California, and it is just a matter of time before another follows the expected 100–200 year cycle. Warning would be a nice thing, but seismologists are not particularly successful in this, possibly because there is insufficient instrumental coverage of the earth's surface to study earthquakes. There is the international seismic network, but instruments have only local coverage and usually are set for optimizing the range of deformation, foreshocks, and other crustal changes that could provide warning. It would be a first step to determine what changes actually do give reliable forecasts of major earthquakes, and a range of seismographs, strain meters, and satellite detectors could be used to good advantage. According to the Panel on Crustal Movement Measurements (National Research Council Assembly of Mathematical and Physical Sciences' Committee on Geodesy and Seismology), ‘…The frequency with which geodetic networks are re-observed is often of the order of years or tens of years, while most… seismographs are designed to register ground motion excited by an earthquake, and their response is most favorable in a range of periods from, say, one tenth of a second to a few minutes.’ (Geodetic Monitoring of Tectonic Deformation—Toward a Strategy, 119 pp., National Academy of Sciences Press, Washington, D.C., 1981.)
Free-volume mean sizes of polymers probed by positron annihilation spectroscopy: a correlation of results obtained by PAL and by ACAR methods

Abstract Positron annihilation spectroscopy (PAS) has been developed to analyze the microstructure of polymers. Both positron annihilation lifetime (PAL) and angular correlation of positron annihilation radiation (ACAR) measurements give direct information about the mean hole sizes of free-volume holes in amorphous materials. Parallel experiments of PAL and ACAR have been performed in an epoxy polymer as a function of temperature. The free-volume mean hole radii ranging from 2.3 to 3.2 A are obtained. The results obtained by PAL and ACAR agree with each other very well. A correlation of mean free-volume hole sizes obtained by these two methods is established.
Role of Tertiary Collimation for Linac‐Based Radiosurgery

For the stereotactic irradiation of intracranial lesions with a linear accelerator, the use of a tertiary collimating system can be expected to confer several benefits in comparison to the use of the standard linac collimating jaw system. Moving the collimator closer to the patient should lead to reduced penumbra and reduced susceptibility to positioning error. In addition, the use of a circular rather than a square aperture should yield a more advantageous dose distribution for irradiation techniques which follow spherical geometry. An investigation using film dosimetry with a tissue-equivalent head phantom demonstrated that the tertiary system was superior to the standard jaw system as expected. © 1993 Wiley-Liss, Inc.
Using Videotape to Teach Foreign Languages

Although the videotape recorder can be used effectively in foreign language teaching, its versatility has not been fully exploited. This article outlines several projects for integrating the videotape into language activities. The emphasis is on local production, not commercially prepared programs.
INTERACTION OF ETHANOL AND ANOXIA WITH MUSCARINIC RECEPTOR : STIMULATED PHOSPHOINOSITIDE METABOLISM DURING BRAIN DEVELOPMENT

The mechanism(s) by which ethanol induces alterations in brain development may involve direct actions (e.g. changes in specific biochemical pathways), or indirect effects, such as cerebral hypoxia resulting from ethanol - induced circulatory changes. Since both ethanol and hypoxia are known to affect the metabolism of phosphoinositides, which has been suggested as a possible target for ethanol's developmental neurotoxicity, in the present study we have investigated the in vitro effects of both severe hypoxia (anoxia) and ethanol (alone or in combination) on muscarinic receptor-stimulated phosphoinositide metabolism in cerebral cortex slices from neonatal rats. Anoxia markedly inhibited carbachol - stimulated phosphoinositide metabolism in adult rats (67%), but only slightly (10%) in neonatal animals. Reoxygenation reversed the effect of anoxia at both ages. On the other hand, ethanol's inhibitory effect was pronounced in neonatal rats only, and was additive to that of anoxia. The presence of ethanol did not affect the recovery of carbachol - stimulated phosphoinositide metabolism following anoxia and reoxygenation. These results indicate that ethanol and anoxia differently and independently affect muscarinic receptor - stimulated phosphoinositide metabolism and may mutually contribute to the CNS effects observed following developmental ethanol exposure.
Analysis of heat transfer phenomena in glass-to-metal seals

Abstract An analysis of the literature related to the glass to metal sealing is presented along with a synthesis and derivation of a set of governing equations and boundary conditions. The results of high-speed photography of the actual process which identify and isolate the key regimes in the process are presented. These results enhance a basic understanding of the physical mechanisms involved in the sealing process. Preliminary experimental results provide perspectives in the development of appropriate assumptions and boundary conditions which can be used for future modeling efforts.
UPV Method for Detecting Properties of Carbon-Nanofiber Concrete

Concrete is the most widely used construction material, and the addition of carbon-nanofibers (CNF) to concrete has many advantages in both mechanical and electrical properties such as higher strength, a higher Young's modulus, improved fatigue resistance in addition to self-monitoring behavior due to the high tensile strength and high conductivity. In this study, the Ultrasonic Pulse Velocity (UPV) method was used to characterize properties of concrete containing carbon-nanofibers. Concrete strength correlations between pulse velocity, electrical resistance variation and destructive tests were analyzed. The experimental results indicate that the compressive strength, pulse velocity and percent reduction in electrical resistance while loading concrete containing CNF are much greater than those of plain concrete.
Effective Absorption Cross-Sections in Porphyridium cruentum: Implications for Energy Transfer between Phycobilisomes and Photosystem II Reaction Centers

Effective absorption cross-sections for O2 production by Porphyridium cruentum were measured at 546 and 596 nanometers. Although all photosystem II reaction centers are energetically coupled to phycobilisomes, any single phycobilisome acts as antenna for several photosystem II reaction centers. The cross-section measured in state I was 50% larger than that measured in state II.
The cage culture of some marine fishes in the intake and discharge canals of a steam-electric generating station, Galveston Bay, Texas

Several species of marine fishes were cultured in cages in the intake and discharge canals of the P. H. Robinson Generating Station on Galveston Bay, Texas. Survival in the intake canal cages of Atlantic croaker (Micropogonundulatus), pinfish (Lagodonrhomboides), Florida pompano (Trachinotuscarolinus), white mullet (Mugilcurema), spot (Leiostomusxanthurus), and black drum (Pogoniascromis) was on the average 70% or greater, while that of pigfish (Orthopristischrysoptera), Gulf kingfish (Menticirrhuslittoralis), and silver perch (Bairdiellachrysura) was less than 70%. With the exception of pinfish, survival of caged fish in the discharge canal was extremely poor. Gas-bubble disease was the probable cause of their mortality. Only croaker and pompano adapted to surface feeding in cages. Croaker, pinfish, and pompano cultured in cages were rated acceptable by a 12-member taste panel. Mean taste evaluation scores for croaker, pinfish, and pompano for the appearance, flavor, and overall satisfaction categories were not significantly different (P=0.01). After about 1 year in the water, most cages used in the intake canal were in goad condition, but those located in the discharge canal were in poor condition.