cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of initial powder particle size on the hot workability of powder metallurgy Ni-based superalloys

Abstract The effect of the initial powder particle size on the hot workability of Ni-based superalloys was investigated. Herein, four powders with different particle size ranges ( 106 μm) exhibited superior hot workability than that of the sample fabricated using the powder with finer particles (
Optimal Investments to Improve Grid Resilience Considering Initial Transient Response and Long-term Restoration

This paper presents a multi-time period two-stage stochastic mixed-integer linear optimization model which determines the optimal hardening investments to improve power system resilience to natural disaster threat scenarios. The input to the optimization model is a set of scenarios for specific natural disaster events, that is based on historical data. The objective of the optimization model is to minimize the expected weighted load shed from the initial impact and the restoration process over all scenarios. The optimization model considers the initial impact of the severe event by using electromechanical transient dynamic simulations. The initial impact weighted load shed is determined by the transient simulation, which allows for secondary transients from protection devices and cascading failures. The rest of the event, after the initial shock, is modeled in the optimization with a multi-time period dc optimal power flow (DCOPF) which is initialized with the solution from the dynamic simulation. The first stage of the optimization model determines the optimal investments. The second stage, given the investments, determines the optimal unit commitment, generator dispatch, and transmission line switching during the multi-time period restoration process to minimize the weighted load shed over all scenarios. Note, an investment will change the transient simulation result, and therefore change the initialization to the DCOPF restoration model. The investment optimization model encompasses both the initial impact (dynamic transient simulation results) and the restoration period (DCOPF) of the event, as components come back online. The model is tested on the IEEE RTS-96 system.
Evaluation of Hot Workability of Powder Metallurgy Ni-Based Superalloy with Different Initial Microstructures

The effect of the initial microstructure on the hot workability of a powder metallurgy Ni-based superalloy was investigated in the high-temperature range of 950 °C to 1180 °C and strain rate range of 0.001 to 1.0 s−1. Six samples with different initial microstructures were fabricated by various hot isostatic pressing (HIP) conditions and subsequent treatments such as hot extrusion. The coarse-grained samples exhibited low hot workability regardless of the deformation conditions. In contrast, the hot workability of the fine-grained samples significantly varied depending on the deformation conditions. The hot workability exhibited a peak at the sub-solvus temperature of ~ 1100 °C and decreased at temperatures higher and lower than this temperature. In addition, the hot workability decreased monotonically with increasing the strain rate. The prior particle boundaries (PPBs) acted as cavity nucleation sites and crack paths, especially at lower temperatures and higher strain rates, resulting in early fracture and low hot workability. With decreasing the grain size, the hot workability at the peak temperature improved. The extruded sample with the smallest grain size exhibited the best hot workability, owing to the avoidance of PPB fracture and the acceleration of dynamic recrystallization.
Circumferential shoulder laceration after posterior axilla sling traction: a case report of severe shoulder dystocia

Shoulder dystocia is an unpredictable and potentially catastrophic complication of vertex vaginal delivery. Posterior axilla sling traction (PAST) has recently been proposed as a method to resolve severe shoulder dystocia when commonly used techniques have failed. A 33-year-old woman (gravida 5, para 0) at 35 weeks, 1 day gestation underwent induction of labor for poorly controlled type 2 diabetes mellitus. Delivery of the large-for-gestational-age infant (4,060 g) was complicated by intractable shoulder dystocia, relieved at 3 minutes with PAST, resulting in a deep, circumferential laceration of the fetal posterior shoulder and contralateral phrenic nerve palsy. PAST provides a potentially lifesaving option during intractable shoulder dystocia. Simulation or education about the technique facilitates its use when standard maneuvers fail. It is important to disseminate information about potential complications associated with these novel maneuvers.
Trade-offs in selecting the number of years for estimation of teacher effectiveness

The number of years to estimate value-added measures (VAM) has received insufficient attention. Researchers often use as many years as available, to increase precision and decrease transitory sorti...
A Review of Virtual-Flux Model Predictive Control and Receding Horizon Estimation in Motor Drives

Model predictive control and receding horizon estimation are advanced control and estimation techniques for next-generation high performance motor drives. These methods benefit from low noise and accurate system models, which are challenging to realize with parameter-based motor models. The idea of virtual-flux, where the machine is modelled with flux instead of current, has been seen as a solution, as the parameters and their nonlinearities can be captured by a function that maps measured current onto the corresponding flux it generates. In this way, all system information can be encoded in a single static function, simplifying the stability and robustness analyses, as well as online computational requirements. Furthermore, virtual-flux modelling allows for many electric machines and even the electric grid to be described in a similar way. This review condenses the results in literature into a uniform virtual-flux framework and explores the applications and potential of model predictive control and receding horizon estimation. The combination of these concepts is shown to strongly benefit their respective problems, ranging from finite control set and convex control set MPC, full and reduced phase current sensor set flux estimation, and position and speed co-estimation.
Dupuytren Contractures: An Update of Recent Literature

Dupuytren disease is a fibroproliferative disorder that affects the palmar fascia of the hand and results in varying degrees of nodule and cord formation. Over time, patients may develop progressive contractures, impairing their ability to type, to perform with fine instruments, or to participate in social activities such as shaking hands. Treatment options for Dupuytren contractures include needle aponeurotomy (NA), injection of collagenase Clostridium histolyticum (CCH) with manipulation of the digits, and surgical fasciectomy. Over the past decade, the use of CCH has increased. Recent studies have provided additional data regarding the pathophysiology, indications, outcomes, and costs associated with the treatment for Dupuytren contractures, and this review highlights these advances.
3D Cerebral Cortical Morphometry in Autism: Increased Folding in Children and Adolescents in Frontal, Parietal, and Temporal Lobes

This paper presents a systematic evaluation of cortical folding, or complexity, in autism. It introduces two novel measuresto analyze folding in a specific region of interest, which, unlike traditional measures, produce an intuitive easily-interpretable description of folding and inform the nature of folding change by incorporating local surface-patch orientation. This study reports newfindings of increasedcortical folding in autistics in the frontal, parietal, and temporal lobes, as compared to controls. These differences are stronger in children than adolescents. The paper validates part of the findings using the new measures based on comparisons with traditional measures. Unlike studies in the literature, this paper reports new findings, via a fully 3Dfolding analysis on all brain lobes, based on the consensus of virtually all6 folding measures used (2 new, 4 traditional) via rigorous statistical permutation testing. In these ways, this paper not only strengthens some previous clinical findings, but also extends the state of the art in autism research.
The Trauma Symptom Inventory: Factors Associated with Invalid Profiles in a Sample of Combat Veterans with Post-Traumatic Stress Disorder

The assessment of combat-related post-traumatic stress disorder (PTSD) relies upon self-reported symptoms and the need for indicators of valid reporting is critical. The Trauma Symptom Inventory (TSI) is a testing instrument specific to PTSD which includes validity scales. In a pilot study examining the use of the TSI with combat veterans, 50 male veterans diagnosed with PTSD were administered the TSI. Nineteen percent of the profiles were invalid, all but one based on the Atypical Response Scale. Differences between veterans with valid and invalid TSI profiles are examined in terms of demographic and historical factors, TSI profiles, and individual scale items. The model best able to predict invalid profiles included high scores on subscales measuring dissociative experiences and tension reduction behaviors. Implications for the interpretation of TSI validity scales in assessing combat-related PTSD are discussed.
Lipid Metabolism and Regulation of Membrane Trafficking

The past 20 years have witnessed tremendous progress in our understanding of the molecular machinery that controls protein and membrane transport between organelles (Scheckman R, Orci L. Coat proteins and vesicle budding. Science 1996;271: 1526–1533 and Rothman JE. Mechanisms of intracellular protein transport. Nature 1994;372: 55–63.) The research efforts responsible for these impressive advances have largely focused on the identification and characterization of protein factors that participate in membrane trafficking events. The role of membranes and their lipid constituents has received considerably less attention. Indeed, until rather recently, popular models for mechanisms of membrane trafficking had relegated membrane lipids to the status of a passive platform, subject to deformation by the action of coat proteins whose polymerization and depolymerization govern vesicle budding and fusion reactions. The 1990s, and particularly its last half, has brought fundamental reappraisals of the interface of lipids and lipid metabolism in regulating intracellular membrane trafficking events. Some of the emerging themes are reviewed here.
Centennial- to Millennial-Scale Geomagnetic Field Variations

This chapter describes the paleomagnetic data that are available for studying the geomagnetic field on centennial to millennial timescales, concentrating on the record for the past 10 000 years. Various types of data and their geographic and temporal data coverage are discussed together with an assessment of the quality of the paleomagnetic data and the limitations imposed by the age constraints that are commonly available. The basic methods used for both regional and global syntheses of the data are outlined. Regional secular variation curves provide a means to assess the geographic scale of secular variation and are often used for magnetic dating, that is, to generate age constraints for materials with otherwise unknown or questionable chronologies. Commonly used methods vary widely, ranging from eyeball fits of geomagnetic features in disparate records to sophisticated Bayesian techniques. Global modeling of the field has allowed the development of low-resolution time-varying spherical harmonic descriptions of geomagnetic field behavior. In geomagnetism, these are used to evaluate the persistence of features like the high-latitude flux patches found in the historical field, to determine the extent to which westward and eastward drifts have contributed to geomagnetic secular variations, and to monitor changes in the geomagnetic dipole moment over the past 10 ky. Predictions from global models are compared with conventional paleomagnetic proxies like virtual geomagnetic poles and virtual dipole moment variations. The current rate of change of the geomagnetic dipole moment lies within the range of variations seen over the past 10 ky. Some applications of millennial-scale geomagnetic studies in other fields are briefly discussed: reconstruction of historical events, separation of solar and geomagnetic influences on variations in cosmogenic nuclide production rates, exposure dating, and high-resolution regional magnetostratigraphic applications. The chapter concludes with an assessment of prospects for further developments in studies of the Holocene magnetic field and a list of electronic resources for data and geomagnetic field models.
The Burger Court and the Conflict over the Rational Basis Test: The Untold Story of Massachusetts Board of Retirement v. Murgia

When discussing the evolution of the rational basis test, few if any commentators would rank Massachusetts Bd. of Retirement v. Murgia with San Antonio Indep. School District v. Rodriguez and Railroad Retirement Bd. v. Fritz and City of Cleburne v. Cleburne Living Center in terms of doctrinal significance. In Murgia, the Court rejected an equal protection challenge to a Massachusetts statute that required police officers to retire at age 50, but made no effort to refine the parameters of rational basis analysis. Instead, the brief per curiam opinion simply noted that the rational basis test was “a relatively relaxed standard reflecting the Court's awareness that the drawing of lines that create distinctions is peculiarly a legislative task and an unavoidable one” and that “perfection in making the necessary classifications is neither possible nor necessary.”In fact, however, the internal deliberations of the Court in Murgia played a central role in the evolution of modern rational basis jurisprudence. During those deliberations, Justices William Brennan and Lewis Powell made a concerted effort to unite a majority of the justices behind an opinion that would have committed the Court to a version of the rational basis test that was significantly less deferential than the approach that had been followed by the Warren Court. When this effort failed, it became clear that the justices were irrevocably divided, and that no single, definitive formulation could command majority support. Thus, the members of the Court simply agreed to disagree, and the core issue remained unresolved for the remainder of Burger’s tenure.
Coherent lidar range processing of broadband optical noise waveforms

We present proof-of-concept results for coherent 'time-of-flight' lidar range processing of broadband analog optical noise waveforms using the spectral sensing material Tm:YAG. Time-of-flight resolution of /spl sim/450 ps with /spl sim/30 dB of signal-to-noise ratio is demonstrated.
Understanding team mental models affecting Kaizen event success

Purpose – The purpose of this study is to identify inhibitors and enablers of Kaizen event effectiveness, as perceived by participants, and categorize them into shared mental models to understand the factors participants believe to be affecting Kaizen event success. The findings are also interpreted using the lens of attribution bias and previous studies of Kaizen event effectiveness. Design/methodology/approach – A qualitative approach involving coding responses from participants was adopted. The identified significant inhibitors and enablers were then assigned to shared mental model types using a mapping and categorization approach. Findings – The results are largely consistent with previous studies and show that job/task and technology/equipment mental models dominate participant views of inhibitors, while enablers were primarily drawn from team and team interaction mental models. This also suggests that attribution bias is present. Research limitations/implications – The methods used to measure shared...
Selective Retinoic Acid Receptor γ Agonists Promote Repair of Injured Skeletal Muscle in Mouse.

Retinoic acid signaling regulates several biological events, including myogenesis. We previously found that retinoic acid receptor γ (RARγ) agonist blocks heterotopic ossification, a pathological bone formation that mostly occurs in the skeletal muscle. Interestingly, RARγ agonist also weakened deterioration of muscle architecture adjacent to the heterotopic ossification lesion, suggesting that RARγ agonist may oppose skeletal muscle damage. To test this hypothesis, we generated a critical defect in the tibialis anterior muscle of 7-week-old mice with a cautery, treated them with RARγ agonist or vehicle corn oil, and examined the effects of RARγ agonist on muscle repair. The muscle defects were partially repaired with newly regenerating muscle cells, but also filled with adipose and fibrous scar tissue in both RARγ-treated and control groups. The fibrous or adipose area was smaller in RARγ agonist–treated mice than in the control. In addition, muscle repair was remarkably delayed in RARγ-null mice in both critical defect and cardiotoxin injury models. Furthermore, we found a rapid increase in retinoid signaling in lacerated muscle, as monitored by retinoid signaling reporter mice. Together, our results indicate that endogenous RARγ signaling is involved in muscle repair and that selective RARγ agonists may be beneficial to promote repair in various types of muscle injuries.
Effect of Rifampin on the Development of Ribonucleic Acid Bacteriophage Qβ

Abstract The drug rifampin, when added at the time of infection, inhibits synthesis of the phage Qβ. Both viral ribonucleic acids and viral proteins are made in nearly the same amount as in the absence of rifampin, but the rate of assembly into phage particles is low.
Quantitative measurement of microsomal subfractions isolated from livers of rats fed with 1, 1, 1-trichloro-2, 2-bis (p-chlorophenyl) ethane (DDT)☆

Abstract Fractions enriched in smooth and rough endoplasmic reticulum were prepared from rat liver microsomal membranes by centrifugation and were characterized by analysis of their protein, RNA and phospholipid contents and by electron microscopy. Upon inclusion of 1, 1, 1-trichloro-2, 2-bis ( p -chlorophenyl) ethane (DDT) in the diet, the amount of liver smooth endoplasmic reticulum increased rapidly and transitorily in both weanling and adult rats to approximately twice that of control animals. The increase was more pronounced in males than in females irrespective of age, but the rate of increase (although not the maximum extent of proliferation) in male animals became significantly less as they matured.
Price rigidities and institutional variations in markets with posted prices

Standard laboratory posted-offer markets respond slowly and incompletely to demand shocks. In these one-sided markets, where sellers control the setting of prices, very little information is transmitted via the process of exchange. For this reason, traders have trouble distinguishing randomness in their own experience from changes in market fundamentals. This paper reports the results of twelve laboratory markets conducted to assess whether some common variants to standard posted-offer rules can correct the adjustment deficiences. Although discounting, multiple postings and excess demand information all improve performance, we find that response remains poor, and efficiencies low.
Investigation of Scaling of InSb MOSFETs Through Drift–Diffusion Simulation

Abstract Models needed for drift–diffusion simulation of InSb MOSFETs in commercially available simulator are presented and applied to the problem of scaling of the exclusion/extraction InSb MOSFETs. Non-parabolicity, degeneracy, mobility and Auger recombination/generation are explained and modeled. Leakage current and maximum unity current gain frequency of the exclusion/extraction MOSFET are examined and its scaling properties down to 0.15 μm are analyzed. Because of its high mobility and saturation velocity, InSb shows promise as a material for THz active devices operating at very low voltages, despite its low bandgap and resulting leakage currents.
Telomeres Do D-Loop–T-Loop

The telomere shortening and subsequent loss of function observed in cells that lack telomerase may be due to disruption of the t loop structure. In several organisms in which telomere shortening is seen, telomeres lose the ability to protect against chromosome fusion well before all telomere sequence is lost. Perhaps a minimal length is needed to form a t loop, and once telomeres are sufficiently short, they can no longer protect the end. The minimal length for t loop formation may also be species specific, as are both double-stranded telomere tracts and G strand overhang length. This model can be tested in vivo by looking at senescent human cells as well as telomerase-null mouse and yeast cells. Does the proportion of t loops decline as the telomeres shorten and lose function?Much remains to be learned about the formation and regulation of t loops. The earliest characterization of telomere structure and function involved cytological observations of broken chromosomes by Muller and McClintock in the late 1930s (reviewed in Gall 1995xSee all ReferencesGall 1995). After the identification of telomere DNA sequences in the late 1970s, the telomere field went molecular. In the past 20 years we have learned much about telomere synthesis as well as how biochemical interactions of DNA and telomere proteins regulate telomere length. But now, 60 years after the experiments of Muller and McClintock, cytology has quietly snuck up from behind and made us take notice. The simple visualization of telomeres has again given us a new view of telomere structure and function.
On the second-order cost of TDMA for Gaussian multiple access

Time division multiple access (TDMA) is widely considered to be a practical multi-access communication scheme that can achieve the highest possible sum-rate with appropriate power allocation. Exploring a Gaussian multiple access channel, we show that this result does not carry over to second-order coding rates. In particular, as the number of users grows, the cost of using TDMA is significant relative to the largest known achievable second-order sum-rate for the Gaussian MAC. The latter sum-rate is established by a random coding argument with non-i.i.d. spherical inputs, which is conveniently analyzed via a central limit theorem (CLT) for functions.
Improving LULUCF Offset Projects: A Carbon Performance Standard and Ecosystem Services

The performance standard procedure, a quantitative method for quantifying baseline greenhouse gas (GHG) emissions or removals, provides an alternative approach to the project-by-project methods currently being used in most GHG offset programs. By providing a top-down approach to assessing the three main technical offset accounting elements (setting the baseline, identifying leakage, and monitoring), this approach has the advantage of providing a broader analytical framework for addressing the issues and the ability to focus project developers in areas where such issues can be addressed more comprehensively. In addition, this top-down approach gives the performance standard developer the opportunity to consider the ecosystem services and human impacts in the analysis of where and what types of forestry projects should occur within a geographic area. Although further field study is required to understand the full implementation considerations involved, this procedure has the potential to help reduce some of...
A fuzzy-logic control language for embedded controllers

Abstract Microcontrollers are being used in many commercial and consumer products to introduce a higher level of intelligence. There exist an opportunity and need to develop high-level languages to be used specifically in industrial product development. A recent trend in such embedded applications is the use of fuzzy-logic control. An ongoing project in the Industrial Research Laboratory at the University of Florida investigates the various aspects of microcontroller architectures, operating systems and languages. This report summarizes our progress in developing a fuzzy-logic control language for microcontrollers.
Tracer flux ratios: a phenomenological approach.

The kinetic behavior of tracer flows across epithelial membranes is examined and attention is called to the conditions under which unidirectional tracer flows may be described by first order rate equations. It is shown that the first order nature of the tracer rate equations when combined with simple thermodynamic constraints on tracer flow yields a relation between theratio of the unidirectional rate coefficients and thermodynamic driving forces. The form of this relation is examined for the case of simple diffusion and in the presence of coupled processes.
Nordheim-Gorter evidence for nickel clusters in Cu-rich CuNi thermopower measurements☆

Abstract CuNi-alloy thermopower data on 6.2, 11.6, and 23.6 at.% Ni samples has been quantitatively separated into Ni-cluster and normal impurity-disorder components, using Nordheim-Gorter plots. The normal disorder component is shown to be consistent with dilute CuNi-alloy data.
The principle of equivalence

Abstract The principle of equivalence is examined in its role as a test which a prospective theory of gravitation must satisfy. This point of view suggests that the commonly stipulated property of “locality” is inherent in the gravitational field and not in the principle. The original formulation of Einstein ( 1 ) is taken to be correct and complete. This is a “strong” principle in the sense of Dicke ( 8 ). The “weak” principle, i.e., the postulation of no more than equivalence of inertial and gravitational mass, can be satisfied by theories which predict a smaller gravitational acceleration for a rotating than for a nonrotating object. Consequently, only the strong form can be considered to be acceptable. The situation is illustrated by application (due originally to Einstein) to the first theory of Nordstrom ( 10 ), a simple, special relativistic generalization of Newtonian theory, and the general theory of relativity.
A Case for the Implementation of Cognitive-Communication Screenings in Acute Stroke

Purpose The purpose of this article was to illustrate the importance of the implementation of cognitive-communication screenings in acute stroke and to discuss the need for further research on whet...
Membrane-tethered mucins have multiple functions on the ocular surface

Membrane-tethered mucins are large glycoproteins present in the glycocalyx along the apical surface of all wet-surfaced epithelia of the body, including that of the ocular surface. Originally thought to function only in epithelial surface lubrication and hydration, data now indicate that the mucins are multifunctional molecules, each having unique as well as common functions. This review summarizes current knowledge regarding the three major membrane mucins of the ocular surface, MUC1, MUC4, and MUC16. The mucins vary in their ocular surface distribution, size, structural motifs, and functions. The ectodomains of each are released into the tear film and are, thus, a component of the soluble mucins of the tear film. Both animal and in vitro models for their study are herein described, as are alterations of the mucins in ocular surface disease.
An experimental test of affect, subjective craving, and alcohol outcome expectancies as motivators of young adult drinking

Research on motivations for alcohol use suggests that both positive and negative affect, craving, and outcome expectancies are good predictors of alcohol consumption. The present study tested the utility of these variables in predicting laboratory measures of alcohol consumption among young social drinkers. Two conditioning models of alcohol procurement guided analyses: the conditioned withdrawal model (represented by negative affect and craving) and the appetitive-motivational model (represented by positive outcome expectancies and subjective evaluations). Results showed that negative affect and craving did not significantly influence either subjects' latencies to begin drinking or speed of consuming one placebo beverage. Positive outcome expectancies and evaluations, however, had a marked impact on speed of drinking. Thus, the appetitive-motivational model appears to better characterize the drinking patterns of young social drinkers than does the conditioned withdrawal model.
The chronoamper ometric determination of dissolved oxygen using membrane electrodes

Summary This work has shown that the use of chronoamperometry has both eliminated the need for a stirring apparatus in dissolved oxygen measurement, and increased the sensitivity of the measurement over that found when the electrodes are used in the conventional manner.
Interplanetary Coronal Mass Ejections Observed in the Heliosphere: 1. Review of Theory

With the recent advancements in interplanetary coronal mass ejection (ICME) imaging it is necessary to understand how heliospheric images may be interpreted, particularly at large elongation angles. Of crucial importance is how the current methods used for coronal mass ejection measurement in coronagraph images must be changed to account for the large elongations involved in the heliosphere. In this review of theory we build up a picture of ICME appearance and evolution at large elongations in terms of how it would appear to an observer near 1 AU from the Sun. We begin by revisiting the basics of Thomson scattering describing how ICMEs are detected, in this we attempt to clarify a number of common misconceptions. We then build up from a single electron to an integrated line of sight, consider the ICME as a collection of lines of sight and describe how a map of ICME appearance may be developed based on its appearance relative to each line of sight. Finally, we discuss how the topology of the ICME affects its observed geometry and kinematic properties, particularly at large elongations. This review is the first of a three-part series of papers, where a review of theory is presented here and a model is developed and used in subsequent papers.
Gastric Emptying and First-Pass Metabolism of Ethanol in Elderly Subjects with and without Atrophic Gastritis

Background: Oral ethanol intake results in lower blood ethanol concentrations than intravenous administration of the same dose of ethanol. This first-pass metabolism is thought to be due to gastric metabolism of ethanol via alcohol dehydrogenase and also to hepatic first-pass metabolism. Methods: Since a loss of gastric mucosa may decrease first-pass metabolism of ethanol, this metabolism was studied in 10 elderly subjects (6 women and 4 men) with atrophic gastritis and bacterial overgrowth and in 17 control subjects with normal gastric secretory function. Atrophic gastritis was verified by means of the serum pepsinogen I to pepsinogen II ratio and the hypochlorhydria occurring after pentagastrin stimulation. Bacterial overgrowth was assessed by bacterial counts in gastric juice. The study was repeated after tetracycline treatment to decrease gastric bacteria. In addition, gastric emptying rates of ethanol solution with technetium-99m sulfur colloid were calculated from scintigraphic images. Furthermore, ...
Learning-induced axonal remodeling: Evolutionary divergence and conservation of two components of the mossy fiber system within Rodentia

Damage to the hippocampal formation results in profound impairments in spatial navigation in rats and mice leading to the widely accepted assumption that the hippocampal cellular and molecular memory mechanisms of both genera are conserved. Recently our group has shown in two rat strains that hippocampal-dependent training in the water maze specifically induces robust 'sprouting' of granule cell suprapyramidal mossy fiber axon terminal fields. Here we sought to investigate whether the pronounced remodeling of adult hippocampal circuitry observed in the rat is also present in the mouse motivated by the thought that subsequent studies using genetically-engineered mice could then be implemented to explore the molecular mechanisms underlying training-dependent axonal growth in adult rodents. However, in contrast to Wistar rats, no changes in the Timm's-stained area of mossy fiber terminal fields (MFTFs) were observed in C57BL/6J or 129Sv/EmsJ inbred wild-type mice after water maze training. Neither extending the duration of training nor scaling down the size of the apparatus was able to induce sprouting in mouse mossy fiber pathways. Though there may be similarities in the ultimate output of the hippocampus of rats and mice as inferred from lesion studies, the current results, as well as differences in learning and memory characteristics between the two genera, suggest that the way in which the component circuitry functions is likely to be different; a not too surprising conclusion given the substantial evolutionary distance between them (>20 million years). The present findings afford an opportunity for uncovering linkages between evolutionarily significant alterations in hippocampal circuitry in relation to genera-specific information storage requirements.
Understanding movement data and movement processes: current and emerging directions

Animal movement has been the focus on much theoretical and empirical work in ecology over the last 25 years. By studying the causes and consequences of individual movement, ecologists have gained greater insight into the behavior of individuals and the spatial dynamics of populations at increasingly higher levels of organization. In particular, ecologists have focused on the interaction between individuals and their environment in an effort to understand future impacts from habitat loss and climate change. Tools to examine this interaction have included: fractal analysis, first passage time, Levy flights, multi-behavioral analysis, hidden markov models, and state-space models. Concurrent with the development of movement models has been an increase in the sophistication and availability of hierarchical bayesian models. In this review we bring these two threads together by using hierarchical structures as a framework for reviewing individual models. We synthesize emerging themes in movement ecology, and propose a new hierarchical model for animal movement that builds on these emerging themes. This model moves away from traditional random walks, and instead focuses inference on how moving animals with complex behavior interact with their landscape and make choices about its suitability.
Dissolutive wetting of Ag on Cu: A molecular dynamics simulation study

Abstract Reactive wetting in the eutectic AgCu system is studied with molecular dynamics simulations. As Ag(l) spreads on the Cu surface, Cu dissolves into the liquid. The results for reactive wetting are compared to simulations in which no mixing is permitted, demonstrating that wetting kinetics are enhanced by dissolution reactions. The time dependent radius of the droplet R ( t ) is used to quantify kinetics for the wetting geometry of an infinitely long cylinder spreading on a substrate. Data show that, when dissolution is dominant, spreading is well described by R ( t ) ∼ ( R 0 t ) 1/2 , where R 0 is the starting cylinder radius. Contact angle θ ( t ) data were calculated via a method that accounts for structure near the contact region and compared to data obtained using circular fits to the droplet profile. Significant differences were observed due to molecular scale structure that rapidly evolves near the contact line. This structure exhibits markedly lower θ than what is predicted from droplet profile data and it is proposed to exist throughout most stages of dissolutive wetting. Simulations of AgCu binary liquids spreading on Cu demonstrate that wetting kinetics decrease with increasing Cu in the liquid, further emphasizing that wetting kinetics are intrinsically linked to dissolution kinetics. After dissolution is complete, a Ag-rich monolayer of atoms advances diffusively across the Cu surface.
The Collaborative Honors Project in Psychology: Enhancing Student and Faculty Development

A collaborative honors project in psychology, in contrast to the traditional approach, allows more than one student and more than one faculty adviser to investigate a h o d rungs of research issues. W e discuss the advantages and demands of collaborative research and review our experience with one such project.
Instrumentation of the cervicothoracic junction after destabilization.

Study Design. The biomechanics of three different instrumentation constructs applied at the destabilized cervicothoracic junction were evaluated. Objectives. To find an efficient way in restoring stability of the cervicothoracic junction in cases wiht and without laminectomy. Summary of Background Data. Different instrumentation techniques have been evaluated biomechanically and used clinically for managing instabilities between the fourth and sixth cervical vertebrae. These constructs have not been evaluated at the cervicothoracic junction. Methods. Six human spines were tested nondestructively in axial torsion, flexion, and extension withe the C6-T2 motion segments left unconstrained. The three-dimensional displacements and rotations between C7 and T1 vertebrae were measured using a sonic digitizer. After intact testing, a distractive-flexion Stage 3 cervical spinal injury was simulated surgicaly between C7 and T1. The specimens underwent sequantial instrumentation and mechanical testing with three constructs: posterior Synthes lateral mass plate, posterior pediatric Cotrel-Dubousset rot system with lamina hooks and a crosslink, and anterior Synthes cervical locking plate. Results. Posterior stabilization techniques had statistically more stiffness than an anterior plates. The Cotrel-Dubousset system offered the largest stiffness ratio (intrumented/intact) in flexion, extension, and rotation. There was no statistical difference between posterior plates and Cotrel-Dubousset instrumentation. The stiffness of the anterior plate did not differ significantly from the intact spine. Conclusion. Our data show that instability of the cervicothoracic junction can be efficiently restored by either plates, posterior plates, or posterior hook-rod constructs (Cotrel-Dubousset). Posterior constructs showed increased stiffness over anterior plates.
Romantic Vagrancy: Wordsworth and the Simulation of Freedom

A provocative account of Wordsworth's representation of walking as the exercise of imagination, Romantic Vagrancy traces a recurrent analogy between the poet in search of material and the literally dispossessed vagrants and beggars he encounters. Reading Wordsworth - and Rousseau before him - from the perspective of recent debates about the political and social rights of the homeless, Celeste Langan argues that both literature and vagrancy are surprisingly rich and disturbing images of the 'negative freedom' at the heart of liberalism. Langan shows how the formal structure of the Romantic poem - the improvisational excursion - mirrors its apparent themes, often narratives of impoverishment or abandonment. According to Langan, the encounter between the beggar and the passer-by in Wordsworth's poetry does not simply reveal a social conscience or its lack; it represents the advent of the liberal subject, whose identity is stretched out between origin and destination, caught between economic and political forces and the workings of desire.
Ether-Soluble Substances on the Skin of the Human External Auditory Canal1

A study of the ether-soluble substances found on the skin surface of the auditory canal was made as part of an integrated investigation of diseases of the external ear (1). Since only relatively small quantities of ear secretions were available for analysis, it was deemed desirable to adapt microtechnics for measuring the samples of secretion. Such micromethods were developed and applied (2, 3, 4).
Oviductal epithelium of the baboon: Hormonal control and the immuno-gold localization of oviduct-specific glycoproteins

Oviducts were obtained from a series of cycling and ovariectomized steroid-treated baboons. The lining epithelium of the ampulla and isthmus was analyzed by light and electron microscopy. Both morphological and cytomorphometric analyses revealed that the morphological and functional state of the oviductal epithelium in the baboon is controlled by the ovarian steroids. Additionally, a clear cephalocaudal steroid-responsive gradient was observed when the data from the ampulla and isthmus of the same animal were compared. Within the ampulla, estradiol induced hypertrophy, hyperplasia, ciliogenesis, and secretory activity, whereas adding progesterone to the treatment regimen (+/- estradiol) resulted in atrophy, deciliation, apoptosis, and loss of the secretory activity. These cyclic processes were less evident in the isthmus. We also used an indirect electron microscopic immunogold technique and a previously characterized polyclonal antibody to determine the localization of oviduct-specific glycoproteins. These glycoproteins were present in every secretory granule observed, regardless of oviduct region, electron density, or size of the secretory granule. In summary, our data show that 1) estradiol induces and maintains the mature epithelium of the baboon oviduct, 2) steroid withdrawal or the administration of progesterone causes regression of the epithelium, and 3) the previously identified estradiol-dependent oviduct-specific glycoproteins are synthesized within and released from the secretory epithelial cells.
Integrated silicon-photonic module for generating widely tunable, narrow-line RF using injection-locked lasers

We have developed a system for generating widely tunable, narrow-line RF signals from a pair of injection-locked lasers. This system is based on injection seeding one laser with a selectable high-order sideband obtained from a second laser that is phase modulated by a narrow-line, low-frequency RF reference oscillator. When these coherent optical outputs are mixed on a fast photodiode, RF output is obtained, with linewidth and phase noise characteristics that are limited by the reference oscillator. The RF output can be tuned over a wide range, in multiples of the reference frequency, and can be fine-tuned by tuning the reference oscillator. In this paper, we present the results of our efforts to develop an integrated version of this system, based on a silicon-photonic integrated circuit coupled to III-V semiconductor gain chips. We describe the fabrication process of the integrated module using heterogeneous integration techniques, and present preliminary results including two lasers operating simultaneously on a single silicon-photonic chip.
Hydrodynamic interactions in quasi-elastic light scattering from flexible polymers in solution

Abstract Theoretical calculations of the time correlation function and the mean relaxation time of dynamic light scattering from flexible polymers in dilute solutions have been carried out by use of the Rouse-Zimm model in the non-draining limit. The results have been favourably compared with those predicted assuming free draining in their respective fittings to existing experimental data.
Co methanation activity and xps studies of pd supported on zsm5 and y- zeolites

Abstract The hydrogenation of carbon monoxide has been studied on a series of Pd catalysts supported on H-ZSM5, Na-ZSM5, H-Y, Na-Y zeolites and SiO2. Activity studies carried out at atmospheric pressure, and in the temperature range 300-550°C, yielded methane and water as the main reaction products. The methanation activity of the various fresh catalysts varied with the supports used, in the decreasing order H-Y > H-ZSM5 > Na-ZSM5 > Na-Y > SiO2, which indicates that the support acidity affects the activity. Pd supported on ZSM5 (H,Na) zeolites showed remarkable stability towards de- activation even at 500°C, whereas irreversible deactivation occurred on Pd supported on Y-zeolites and SiO2. X-ray photoelectron spectroscopy studies shows no shifts in binding energy indicating that metallic Pd is the predominant active species. CO chemisorption and carbon deposition experiments indicate that carbon deposits causing deactivation occurs only above 400°C. Activity enhancement and catalyst stability are discussed in terms of support acidity.
Responsiveness of acetylcholinesterase and butyrylcholinesterase activities in neural cells to age and cell density in culture

Abstract Acetylcholinesterase activity in neuroblastoma and C-6 glial cells, maintained in monolayer culture, decreased with increasing age and cell density (cells/mm 2 ). Butyrylcholinesterase activity in C-6 glial cells did not change with age, but increased slowly with increasing cell density. AChE reached peak activity at a lower density in neuroblastoma than in C-6 glial cells. The data suggest either that AChE in both cell types is responsive to cell-cell contact or that different enzymes are involved.
Minimally Invasive Thoracic Corpectomy: Surgical Strategies for Malignancy, Trauma, and Complex Spinal Pathologies

The rapid expansion of minimally invasive techniques for corpectomy in the thoracic spine provides promise to redefine treatment options in this region. Techniques have evolved permitting anterior, lateral, posterolateral, and midline posterior corpectomy in a minimally invasive fashion. We review the numerous techniques that have been described, including thoracoscopy, tubular retraction, and various instrumentation techniques. Minimally invasive techniques are compared to their open predecessors from a technical and complication standpoint. Advantages and disadvantages of different approaches are also considered, with an emphasis on surgical strategies and nuance.
A polymer V-shaped electrothermal actuator array for biological applications

A polymer V-shaped electrothermal actuator (ETA) array that is capable of compressing a live biological cell with a desired strain was designed, fabricated and characterized. This polymer electrothermal array is the core of a microelectromechanical systems (MEMS) device to measure the mechanical compliance of a cell. A polymer electrothermal actuation mechanism was selected because it is able to operate in an electrolytic solution (cell medium), which was needed to keep cells alive during testing. The MEMS-based device was optimized utilizing finite element analysis and the devices were fabricated using surface micromachining techniques. Characterization of these devices was conducted in air, deionized water and cell mediums. Operating these devices in liquid environments was performed using direct current voltages less than 2.0 V or high-frequency (800 kHz) alternating current voltages. The actuator displacement was up to 9 µm in air and 3 µm in liquids, i.e. it achieves 30% displacement of that in air when operating in liquids. Such remarkable performance is due to the large coefficient of thermal expansion and low thermal conductivity of the structural polymer (SU-8). Finally, we demonstrated the suitability of this actuator for biological applications by compressing a cultured NIH3T3 fibroblast in the cell medium.
Inhibition of Yogurt Starter Cultures by Jenseniin G, a Propionibacterium Bacteriocin

Abstract Jenseniin G, a heat-stable bacteriocin that is produced by Propionibacterium jensenii P126 (ATCC 4872), inhibits Lactobacillus delbrueckii ssp. bulgaricus NCDO 1489. The purpose of this investigation was to examine effects of jenseniin G on growth and acid production by additional yogurt starter cultures including strains of L. delbrueckii ssp. bulgaricus and Streptococcus thermophilus . Yogurt starters were examined for inhibition by jenseniin G in agar and broth culture media and in skim milk. Jenseniin G inhibited all 12 yogurt starter cultures. Lactobacilli were 2 to 16 times more sensitive than were streptococci. Addition of jenseniin G to broth and milk cultures of starters prevented growth. Addition of jenseniin G (20 to 60 AU/ml) to stationary phase cultures of lactobacilli and streptococci in simulated yogurt limited acid formation and maintained acidity at pH 4.15 to 4.42 for 30 d at 5°C. The yogurt contained more than 10 7 viable organisms/ml, which met the requirements for the Live and Active Cultures seal of the National Yogurt Association. These data suggest the usefulness of jenseniin G in preventing overacidification or postacidification of yogurt.