cssi/SciSciGPT-SciSciNet huggingface dataset:
Low complexity recursive coding of spectrum parameters

A low complexity vector quantization scheme for the recursive coding of speech spectrum parameters is proposed. In this scheme, the joint probability density function (pdf) of the spectrum parameters of successive speech frames is modelled using a Gaussian mixture model whose parameters are estimated using the Expectation Maximization (EM) algorithm. The conditional density of the spectrum parameters of the current speech frame based on the quantized values of the spectrum parameters of previous speech frames is used to generate a new codebook for every current speech frame. An efficient quantization scheme using transform coding and bit allocation techniques which allows easy and computationally efficient mapping from observation to quantized value is developed. Transparent quality speech for the first order fixed rate recursive coding case is achieved at 20 bits per frame.
Kindling reduces sensitivity of CA3 hippocampal pyramidal cells to competitive NMDA receptor antagonists

Abstract Kindling is a form of experimental epilepsy in which periodic electrical stimulation of a brain pathway induces a permanently hyperexcitable state. A previous study demonstrated that kindling enhances the sensitivity of hippocampal CA3 pyramidal cells to NMDA (N- methyl- d -aspartate ) , consistent with a greater expression of NMDA receptors. We have tested the possibility that kindling also changes the sensitivity of these neurons to competitive NMDA receptor antagonists. When depolarizing responses to NMDA were studied with a grease-gap preparation 1–5 months after the last evoked seizure, higher concentrations of competitive antagonist were required to reduce response amplitudes. Schild analysis yielded higher KD values for all three antagonists tested. This finding suggests that kindling provokes the expression by CA3 pyramidal cells of NMDA receptors with reduced affinity for competitive antagonists.
A study on the performance and reliability of magnetostatic actuated RF MEMS switches.

Abstract The magnetostatic radio frequency micro-electro-mechanical system switch is a special latching type of switch that possesses substantially high performance due to low loss, high linearity, and broad bandwidth. This new technology targets applications where high electrical performance and reliability are required in a harsh environment. A study on switch performance and reliability under different environmental conditions is crucial to its applications. In order to assess the reliability under desired environmental and operational conditions, comprehensive humidity and temperature reliability tests were conducted. The humidity test was conducted under high relative humidity and temperature cycling conditions. The thermal aging test was conducted at different temperature levels, which was used to study the fitness of lifetime distribution and validate the suitability of Arrhenius model that can be used for the lifetime prediction at normal operation temperature.
Rapid Seabed Imaging By Frequency Domain Electromagnetic Migration

This paper discusses an application of electromagnetic (EM) migration for sea-bottom EM imaging. We apply to marine EM data the method of frequency domain EM migration developed by Zhdanov et al. (1996) for fast imaging of land EM data. We study a synthetic survey with electric receivers measuring the natural telluric electric field at the sea bottom over a 3-D geoelectrical model of a sea-bottom petroleum reservoir. We also demonstrate that the EM migration can be applied for fast imaging of marine controlled-source electromagnetic data. The results of this modeling show that the migration method can be effectively used for fast sea-bottom imaging of resistive reservoir structures.
Partitioning of 2,4,5,2',4',5'-hexachlorobiphenyl between seawater and air.

PCBs are generally characterized by low vapor pressures; they would not usually be considered volatile. However, they are also characterized by low water solubilities. Studies addressing PCB toxicology have usually employed open aquaria. Therefore, the objective of this investigation was to describe the gas-liquid partitioning of a single PCB isomer, 2,4,5,2{prime},4{prime}5{prime}-hexachlorobiphenyl (HCBP), in seawater within glass aquaria commonly used for toxicological testing. Partitioning may reduce desired exposure levels during testing, seriously effecting results. However, it may be utilized to realistically model environmental conditions during testing. Therefore, the measured H{prime} will be compared to others obtained with specialized purging equipment. 2,4,5,2{prime},4{prime},5{prime}-HCBP was chosen for its presence in common PCB mixtures and high chlorine content, thus low water solubility and high bioaccumulation potential.
Assessing alcohol treatment composite outcome: Further evidence utilizing brief measures

The utility of implementing brief measures in determining alcohol treatment composite outcome status was examined in the present study. Forty-one individuals diagnosed with an alcohol disorder were assessed at intake, immediately following a 3-month out-patient treatment, and then again 6-months and 9-months post-intake. Subjects were classified as abstinent (38%), moderate drinking without problems (22%), heavy drinking or problems (16%), and heavy drinking and problems (24%) at the 9-month follow-up. Those with better composite outcomes had fewer psychiatric problems, better social behavior and role functioning, better mental- and physical-health related quality of life and greater satisfaction-with-life than subjects with poorer composite outcomes. Fully 97% of subjects with 'good' (abstinent, moderate drinking without problems) and 'poor' (heavy drinking and/or problems) outcomes were classified correctly with the non-alcohol-specific functioning measures. Data supports the use of brief, practical mea...
Computer-based regional blood distribution

Abstract This paper describes the regional blood distribution system used in Long Island, New York. A brief review of the theoretical model is given first. Then the operational system is discussed and the automation support is described. Finally, results are presented and evaluated.
CLINICAL STUDIES OF QUINIDIN: II. ALTERATIONS IN THE CARDIAC MECHANISM AFTER ADMINISTRATION OF QUINIDIN TO PATIENTS WITH AURICULAR FIBRILLATION WITH CONSIDERATION OF CERTAIN TOXIC EFFECTS OF THE DRUG

During the past four years, sufficient evidence has been accumulated to indicate that in a certain number of patients suffering from fibrillation of the auricles (about 50 per cent.), oral administration of quinidin sulphate serves to restore the normal cardiac rhythm. The circumstances which determine the issue are not yet altogether clear. A summary of the earlier literature, together with a preliminary report dealing with the treatment of four cases in the Hospital of the Rockefeller Institute, has already appeared. 1 The results of experiments done in this Hospital to determine the pharmacologic action of this drug have likewise been reported. 2 It is the purpose of the present communication to record in detail the alterations in the mechanism of the heart's action which have been observed in the first eleven patients to whom quinidin has been administered. 3 A more detailed report of the experimental studies will appear shortly. A discussion of
Science Signaling Podcast: 25 November 2014

This Podcast features an interview with Catherine Wasser and Joachim Herz, authors of a Research Article that appears in the 25 November 2014 issue of Science Signaling , about modifications to an apolipoprotein E receptor that affect synaptic plasticity and learning. Apolipoprotein E (ApoE) is a lipoprotein that helps transport fat-soluble molecules, such as cholesterol, around the body. In the brain, ApoE delivers cholesterol to neurons by binding to ApoE receptors, which triggers endocytosis of the cargo borne by the ApoE aggregates. ApoE receptors can also initiate intracellular signaling in response to binding to other ligands, such as Reelin. Signaling by the ApoE receptor Apoer2 controls neuronal migration during development, affects synaptic plasticity, and helps break down the β-amyloid plaques associated with Alzheimer9s disease. Wasser et al . report that differential splicing and posttranslational modification of Apoer2 affects synaptic plasticity and learning in mice.
Simultaneous detection of cadmium, copper, and lead using a carbon paste electrode modified with carbamoylphosphonic acid self-assembled monolayer on mesoporous silica (SAMMS)

Abstract A new sensor was developed for simultaneous detection of cadmium (Cd 2+ ), copper (Cu 2+ ), and lead (Pb 2+ ), based on the voltammetric response at a carbon paste electrode modified with carbamoylphosphonic acid (acetamide phosphonic acid) self-assembled monolayer (SAM) on mesoporous silica (Ac-Phos SAMMS). The adsorptive stripping voltammetry (AdSV) technique involves preconcentration of the metal ions onto Ac-Phos SAMMS under an open circuit, then electrolysis of the preconcentrated species, followed by a square wave potential sweep towards positive values. Factors affecting the preconcentration process were investigated. The voltammetric responses increased linearly with the preconcentration time from 1 to 30 min or with metal ion concentrations ranging from 10 to 200 ppb. The responses also evolved in the same fashion as adsorption isotherm in the pH range of 2–6. The metal detection limits were 10 ppb after 2 min preconcentration and improved to 0.5 ppb after 20 min preconcentration.
Flux difference splittings and limiters for the resolution of contact discontinuities

Abstract Harten, Lax, and van Leer developed a theory of approximate Riemann solutions and used it to derive numerical methods for systems of conservation laws. In the first part of this paper, we reformulate this theory so that it can be used to compare various flux difference splitting formulae. In particular we show how to compare the resolution of contact discontinuities by various methods with that of the Roe method. Since the Roe method can resolve an isolated steady contact perfectly, it is a good standard for comparison. In the second part of the paper, we show that Harten's subcell resolution method is the ultimate compressive limiter. We discuss the differences between compressive and noncompressive limiters and show why it is important to choose the limiter to suit the problem at hand.
Experimental Performance Evaluation of a High Temperature PEM Fuel Cell at Different Temperatures and Pressures

The high temperature proton exchange membranes (HT-PEM) attract growing interests due to its enhanced electrochemical kinetics, simplified pinch technology and utilization of higher CO-rich reformed hydrogen as the fuel. From the technological point of view, using pure hydrogen as fuel seems highly restrictive because hydrogen with high purity may not always be readily available. As an attractive alternative to compressed hydrogen, it is preferred to use hydrogen-rich gases as fuel. On-site generation of hydrogen using reformed fuels can be directly fed to the high temperature proton exchange membrane fuel cells (HT-PEMFCs) without first preheating the cell with external heat source to raise the temperature to its operating temperature. Since the HT-PEMFCs performance depends strongly on temperature, the cell temperature plays an important role in its operation. The purpose of this research is to experimentally study a high temperature PEM fuel cell at steady operating conditions. In this work, the performance of the fuel cell has been experimentally examined to unravel the steady-state effects of changes in temperature and pressure at a fixed hydrogen stoichiometry and variable air stiochiometries In particular, the effects that changes in temperature and pressure have on the voltage-current characteristics. Experimental data of this type is needed to develop and validate the fuel cell models, and to help understand and optimize the operation of these devices. In this study, a cell with an active cell area of 45 cm2 based on polybenzimidazole (PBI), doped with phosphoric acid is examined over the entire temperature range of 120°C–180°C with hydrogen of 99.999% purity. The quantitative results obtained from the experiments showed variations in current-voltage characteristics at different pressure and temperatures. The results will be used as a baseline value to under-study the performance of a high temperature PEM fuel cell in terms of current-voltage characteristics, when fueled with a reformate with higher CO concentrations in our future study.Copyright © 2008 by ASME
Putting to a bigger hole: Golf performance relates to perceived size

When people are engaged in a skilled behavior, such as occurs in sports, their perceptions relate optical information to their performance. In the present research, we demonstrate the effects of performance on size perception in golfers. We found that golfers who played better judged the hole to be bigger than did golfers who did not play as well. In follow-up laboratory experiments, participants putted on a golf mat from a location near or far from the hole and then judged the size of the hole. Participants who putted from the near location perceived the hole to be bigger than did participants who putted from the far location. Our results demonstrate that perception is influenced by the perceiver’s current ability to act effectively in the environment.
Schema-Focused Therapy for Major Depressive Disorder and Personality Disorder: A Case Study

This is a single case study of a college age male with major depressive disorder and personality disorder not otherwise specified (NOS). The patient endorsed feelings of sadness, worthlessness, inattention, isolation, and suicidal and homicidal ideation. In addition, the patient endorsed inflexible and pervasive behavioral patterns such as paranoia, isolation, and narcissism. Treatment consisted of schema therapy, with an emphasis on the therapeutic relationship (limited reparenting). The patient completed Young’s Schema Questionnaire (YSQ) prior to initiating treatment and again following treatment. Schemas endorsed at moderate to high levels include Failure, Enmeshment, Abandonment, Emotional Deprivation, Punitiveness, Negativity/Pessimism, and Social Isolation. Following 68 weeks of schema therapy, the patient endorsed all 18 schemas at a “low” level. In addition, whether these findings demonstrated clinically significant change was examined. Results indicate that four out of seven of the patient’s end...
Role of post-chemotherapy surgery in germ cell tumors

Surgery after systemic chemotherapy for advanced testicular cancer has maintained its role in staging and therapeutic management. The clinical outcome is strongly influenced by patient selection and extent of extirpative surgery. Although extensive predictive modeling has attempted to define appropriate post-chemotherapy surgical candidates based on various clinical and pathologic parameters, the accuracy of these models remains controversial. Complete removal of all post-chemotherapy residual masses in nonseminomatous germ cell tumors remains the standard of care and allows for improved prognostication of the long-term oncologic and functional outcome.
Estimation of the number of "true" null hypotheses in multivariate analysis of neuroimaging data.

Abstract The repeated testing of a null univariate hypothesis in each of many sites (either regions of interest or voxels) is a common approach to the statistical analysis of brain functional images. Procedures, such as the Bonferroni, are available to maintain the Type I error of the set of tests at a specified level. An initial assumption of these methods is a “global null hypothesis,” i.e., the statistics computed on each site are assumed to be generated by null distributions. This framework may be too conservative when a significant proportion of the sites is affected by the experimental manipulation. This report presents the development of a rigorous statistical procedure for use with a previously reported graphical method, the P plot, for estimation of the number of “true” null hypotheses in the set. This estimate can then be used to sharpen existing multiple comparison procedures. Performance of the P plot method in the multiple comparison problem is investigated in simulation studies and in the analysis of autoradiographic data.
Reply to Soto-Pantoja et al. and Zhao et al.: Targeting CD47 on human solid tumors

We recently demonstrated that anti-CD47 monoclonal antibodies (mAbs) promote the phagocytosis of solid tumor cells in vitro and inhibit the growth and metastasis of human solid tumors in xenotransplantation models (1). We also observed a significant inhibition of tumor growth in a syngeneic mouse tumor model treated with MIAP410, an anti-mouse CD47 (mCD47) mAb. In contrast, a second blocking anti-mCD47 mAb (MIAP301) produced a moderate, yet insignificant, antitumor effect. The reasons for the lack of MIAP301 activity in this model are unclear, but could simply be due to the statistical power of the study. MIAP410 was previously reported to not block mCD47–mSIRPα interactions (2). In contrast, we have determined that MIAP410 does block mCD47–mSIRPα interactions (Fig. 1). This discrepancy may be attributable to the N-terminal GST-CD47 fusion protein used in the prior blocking assays (2). Polypeptide additions at the N terminus of CD47 prevent the N-terminal glutamine residue of CD47 from forming pyroglutamic acid. As seen in the SIRPα–CD47 complex crystal structure (3), this residue is critical … [↵][1]1To whom correspondence should be addressed. E-mail: irv{at}stanford.edu. [1]: #xref-corresp-1-1
Evaluation of Information Applications of a Self-Organizing Distributed Traffic Information System for a Large-Scale Real-World Traffic Network

This paper presents an evaluation of the system performance of a proposed self-organizing, distributed traffic information system based on vehicle-to-vehicle information-sharing architecture. Using microsimulation, several information applications derived from this system are analyzed relative to the effectiveness and efficiency of the system to estimate traffic conditions along each individual path in the network, to identify possible incidents in the traffic network, and to provide rerouting strategies for vehicles to escape congested spots in the network. A subset of vehicles in the traffic network is equipped with specific intervehicle communication devices capable of autonomous traffic surveillance, peer-to-peer information sharing, and self-data processing. A self-organizing traffic information overlay on the existing vehicular roadway network assists their independent evaluation of route information, detection of traffic incidents, and dynamic rerouting in the network based both on historical information stored in an in-vehicle database and on real-time information disseminated by intervehicle communications. A path-based microsimulation model is developed for these information applications and the proposed distributed traffic information system is tested in a large-scale real-world network. Based on simulation study results, potential benefits both for travelers with such equipment as well as for the traffic system as a whole are demonstrated.
Interest Group Competition and Coalition Formation

This article investigates how interest group competition, a state of conflicting policy preferences stemming from how organizational memberships are defined, can resolve into conflict or cooperation. The strategic choices of competing lobbyists are modeled as the results of a trade-off between the need to represent members and please legislators, and the additional advocacy resources they hope to gain by agreeing to form coalitions with their competitors rather than fight them in resource-draining conflicts. Hypotheses derived from the model are tested with data from interviews with lobbyists on six issues taken up by the U.S. Congress from 1999 to 2002. The results suggest that while group members do have some limited power to constrain the policy positions taken on issues by their lobbyists, it is primarily the pressures from legislators and competitor groups that push lobbyists into collectively supporting coalition positions different from those desired by their members.
Characterizing arid region alluvial fan surface roughness with airborne laser swath mapping digital topographic data

[1] Range-front alluvial fan deposition in arid environments is episodic and results in multiple fan surfaces and ages. These distinct landforms are often defined by descriptions of their surface morphology, desert varnish accumulation, clast rubification, desert pavement formation, soil development, and stratigraphy. Although quantifying surface roughness differences between alluvial fan units has proven to be difficult in the past, high-resolution airborne laser swath mapping (ALSM) digital topographic data are now providing researchers with an opportunity to study topography in unprecedented detail. Here we use ALSM data to calculate surface roughness on two alluvial fans in northern Death Valley, California. We define surface roughness as the standard deviation of slope in a 5-m by 5-m moving window. Comparison of surface roughness values between mapped fan surfaces shows that each unit is statistically unique at the 99% confidence level. Furthermore, there is an obvious smoothing trend from the presently active channel to a deposit with cosmogenic 10Be and 36Cl surface exposure ages of ∼70 ka. Beyond 70 ka, alluvial landforms become progressively rougher with age. These data suggest that alluvial fans in arid regions smooth out with time until a threshold is crossed where roughness increases at greater wavelength with age as a result of surface runoff and headward tributary incision into the oldest surfaces.
An IUE Atlas of Pre-Main-Sequence Stars. I. Co-added Final Archive Spectra from the SWP Camera

We have identified 50 T Tauri stars (TTS) and 74 Herbig Ae/Be (HAEBE) stars observed in the IUE short-wavelength bandpass (1150-1980 A). Each low-resolution (R ~ 6 A) spectrum was visually inspected for source contamination and data quality, and then all good spectra were combined to form a single time-averaged spectrum for each star. Use of IUE Final Archive spectra processed with NEWSIPS reduces fixed pattern noise in individual spectra, allowing significant signal-to-noise ratio gains in our co-added spectra. For the TTS observed by IUE, we measured fluxes and uncertainties for 17 spectral features, including two continuum windows and four fluoresced H2 complexes. Thirteen of the 32 accreting TTS observed by IUE have detectable H2 emission, which until now had been reported only for T Tau. Using an empirical correlation between H2 and C IV line flux, we show that lack of sensitivity can account for practically all nondetections, suggesting that H2 fluorescence may be intrinsically strong in all accreting TTS systems. Comparison of IUE and GHRS spectra of T Tau show extended emission primarily, but not exclusively, in lines of H2. We also fit reddened main-sequence templates to 72 HAEBE stars, determining extinction and checking spectral types. Several of the HAEBE stars could not be fitted well or yielded implausibly low extinctions, suggesting the presence of a minority emission component hotter than the stellar photosphere, perhaps caused by white dwarf companions or heating in accretion shocks. We identified broad wavelength intervals in the far-UV that contain circumstellar absorption features ubiquitous in B5-A4 HAEBE stars, declining in prominence for earlier spectral types, perhaps caused by increasing ionization of metal resonance lines. For 61 HAEBE stars, we measured or set upper limits on a depth index that characterizes the strength of circumstellar absorption and compared this depth index with published IR properties.
Imaging properties of retro-reflective materials used in head-mounted projective displays (HMPDs)

The concept of head-mounted projective display (HMPD) has been recently proposed as an alternative to conventional eyepiece-type head-mounted displays (HMDs). An HMPD consists of a pair of miniature projection lenses and flat panel displays mounted on the head and retro-reflective sheeting material placed strategically in the environment. Recent efforts have been made to demonstrate the feasibility of the imaging concept and prototypes have been built. Our research indicates that the quality and properties of the retro-reflective material play critical roles in the overall imaging quality of HMPDs. The retro-reflective sheeting material is commonly used in traffic control and photonic lighting systems, rather than optimized for imaging purpose as in the HMPDs. The size and shape of the microstructures cause artifacts on images. In this paper, we will mainly focus on the evaluation of the various existing retro-reflective materials, and the examination of the impact of the material characteristics on imaging properties. The basic structures of the existing materials are briefly reviewed, the characteristic parameters used to quantify the material properties are defined, and a few samples are evaluated. The characteristics of interest include: the size and shape of the microstructure, the distribution pattern and density of the microstructure, retro-reflectivity, the profile of the reflected light, diffraction artifacts and ghost imaging. Finally, a comprehensive analysis are presented to examine how the material characteristics play their roles in an imaging system, such as the HMPD, and predict the imaging artifacts caused by these characteristics.
DNA bases thymine and adenine in bio-organic light emitting diodes.

We report on the use of nucleic acid bases (NBs) in organic light emitting diodes (OLEDs). NBs are small molecules that are the basic building blocks of the larger DNA polymer. NBs readily thermally evaporate and integrate well into the vacuum deposited OLED fabrication. Adenine (A) and thymine (T) were deposited as electron-blocking/hole-transport layers (EBL/HTL) that resulted in increases in performance over the reference OLED containing the standard EBL material NPB. A-based OLEDs reached a peak current efficiency and luminance performance of 48 cd/A and 93,000 cd/m2, respectively, while T-based OLEDs had a maximum of 76 cd/A and 132,000 cd/m2. By comparison, the reference OLED yielded 37 cd/A and 113,000 cd/m2. The enhanced performance of T-based devices is attributed to a combination of energy levels and structured surface morphology that causes more efficient and controlled hole current transport to the emitting layer.
Patterns of electroconvection in a nematic liquid crystal

We present a survey of pattern formation in electroconvection of the nematic liquid crystal 4-ethyl-2fluoro-4 8-[2-(trans-4-pentylcyclohexyl)-ethyl] biphenyl~I52! as a function of three control parameters: the applied voltage, applied frequency, and electrical conductivity of the sample. The patterns are dominated by oblique-roll states. Over the lower range of conductivity, the initial transition is a supercritical Hopf bifurcation which leads to four degenerate modes: right- and left-traveling zig and zag rolls. For higher values of the conductivity, the primary instability is a subcritical bifurcation to a single set of stationary oblique rolls. The convecting states exhibit a rich variety of patterns as a result of the interactions between the four modes, including states of spatiotemporal chaos and localized states. @S1063-651X~98!08301-9#
Teaching Psychology of Women: A Survey of Instructors:

A 38-item questionnaire was sent to 440 instructors of psychology of women courses; 230 surveys were returned. This article examines characteristics of people who teach courses in psychology of women, characteristics of their institutions, characteristics of the course itself, and the instructors' reactions to the course. Among the findings are: (a) instructors in this course vary greatly in the number of years they have taught the course and in their area of graduate training; (b) few instructors had taken a formal course in psychology of women; (c) the course is usually a highly emotional one; and (d) almost all instructors enjoyed teaching the psychology of women course more than their other courses.
Biogenesis of the bundle-forming pilus of enteropathogenic Escherichia coli: reconstitution of fimbriae in recombinant E. coli and role of DsbA in pilin stability – a review

Abstract Enteropathogenic Escherichia coli (EPEC) adhere to tissue culture cells in a distinct pattern known as localized adherence (LA). We have defined two loci necessary for LA. A plasmid-encoded gene cluster encodes bundlin, the major structural subunit of a type-IV fimbria called the bundle-forming pilus (BFP), a prepilin peptidase necessary for processing of pre-bundlin to its mature form, and twelve other proteins. Under the control of an exogenous promoter, these 14 genes are sufficient for the biogenesis of BFP in a heterologous E. coli host. The chromosomal gene dsbA , which encodes a periplasmic disulfide-bond oxido-reductase, is also required for LA. In the absence of DsbA protein, bundlin is made but rapidly degraded. Pre-bundlin is also rapidly degraded in the absence of DsbA, suggesting that the prepilin is a transcytoplasmic protein simultaneously accessible to enzymes on both sides of the inner membrane. These studies offer a fresh perspective on the biogenesis of type-IV pili.
Effect of counselling rejected blood donors to seek health care

The appropriate public health role of a blood bank has not been completely defined. An evaluation of verbal counselling as an incentive for rejected blood donors to seek follow-up medical care was undertaken. Two groups, deferred from donating blood because of low hematocrits, were compared in terms of compliance rate (percentage seeking medical care). The first group, comprising 60 individuals deferred in a traditional manner with either a brief written or verbal statement, had a compliance rate of 25%. In the second group, comprising 61 individuals to whom additional counselling was offered, 79% requested such counselling. A compliance of 60% was found among those counselled, and an overall compliance rate of 54% was noted in the group as a whole. The more than doubling of the compliance rate indicates that a blood bank can effectively encourage deferred donors, most of whom are asymptomatic, to seek health care.
Replacing the patient: the fiction of prosthetics in medical practice.

The invention of computer simulations used for practicing surgical maneuvers in a video game-like format has an ancestry in the artificial limbs of history and is reflected, grotesquely, in Edgar Allan Poe’s short story, “The Man That Was Used Up” (1850). The nineteenth century worked to ensure that the incomplete body did indeed retain a sense of self by creating prostheses to mimic corporeal wholeness. Our present-day technology seems intent on doing precisely the opposite, deliberately fragmenting the body and challenging our understanding of the body and the prosthetic.
Transient unilateral brachial plexopathy and partial Horner′s syndrome following spinal anesthesia for cesarean section

A healthy 21-year-old primigravida presented for elective cesarean section. At 45 min after intrathecal (IT) injection of bupivacaine, morphine and fentanyl she developed dysphagia, right sided facial droop, ptosis and ulnar nerve weakness. This constellation of signs and symptoms resolved 2 h later. Based on the time course and laterality of her symptoms, as well as the pharmacologic properties of spinal opioids, we believe her symptoms can be attributed to the IT administration of fentanyl.
Hyperglycemia‐induced apoptotic cell death in the mouse blastocyst is dependent on expression of p53

Murine preimplantation embryos exposed to hyperglycemia experience decreased glucose transport, and overexpression of the proapoptotic protein BAX, leading to increased apoptosis. These changes may account for the increased rates of miscarriages and malformations seen in women with diabetes mellitus. To test whether p53 expression is necessary for hyperglycemia-induced apoptosis, p53+/+, +/-, -/- embryos were obtained by superovulation. Two-cell embryos were cultured to a blastocyst stage in 52 mM D- or L-glucose. Apoptosis was detected using terminal dUTP nick end labeling (TUNEL) assays. In vivo studies were performed in the same manner using blastocysts recovered from streptozotocin-induced diabetic mothers. Both in vitro and in vivo studies showed that wildtype embryos had a significantly higher percentage of TUNEL-positive nuclei than p53+/- and -/- embryos. To test whether p53 is upstream of BAX, immunofluorescent confocal microscopy and immunoprecipitation/ immunoblotting were performed on blastocysts cultured in high vs. control glucose conditions. Blastocysts from p53+/+ mice exhibited increased BAX staining vs. p53+/- and -/- embryos. Next, to determine whether a decrease in glucose transport was upstream or downstream of p53, deoxyglucose transport was measured in individual blastocysts from p53+/+ and +/- diabetic vs. nondiabetic mice. Embryos from diabetic p53+/- mice exhibit a 44% decrease in glucose transport, similar to the 38% decrease seen in embryos from diabetic p53+/+ mice. Taken together, these results strongly indicate that p53 plays a role in hyperglycemia-induced apoptosis, upstream of BAX overexpression and downstream of the decrease in glucose transport experienced by the mouse preimplantation embryo.
Biodemography: New Approaches to Understanding Trends and Differences in Population Health and Mortality

The incorporation of biological information in large population surveys has expanded demographic analysis to clarify the meaning of observed trends and differences in population health and mortality. Levels of measured biological risk in the population were reduced in recent years largely because of the expanded use of prescription drugs. The increased use of antihypertensives and, to a lesser extent, lipid-lowering drugs was a likely cause of significant mortality reduction. Blacks and persons with lower educational attainment experience higher levels of biological risk factors, more diseases, and more frailty; these differences are the sources of higher mortality for these groups. Hispanics are less likely to have a higher prevalence of risk factors and diseases than the non-Hispanic population, providing further understanding of the "Hispanic paradox." Almost every examined indicator of biological risk, disease, and frailty is related to higher mortality, indicating how incorporation of this information provides a fuller understanding of the morbidity process.
Effective viscosities in thin ionic micellar liquid films

Thin liquid films stabilized by surfactants above the critical micelle concentration exhibit stratification or stepwise dynamic thinning. A continuum hydrodynamic model is outlined for stepwise film thinning that incorporates equilibrium micellar structuring through self-consistent oscillatory disjoining pressures and effective viscosities. Effective viscosities as functions of thickness are evaluated with an extension of the local average density model, considering dilute colloidal suspension shear viscosities and solvent effects. To establish local shear viscosities, structured DFT micellar profiles, coarse-grained densities, and disjoining pressure are used. Ionic micelles and other colloidal systems with repulsive interactions show structured effective viscosities that are generally less than the corresponding homogeneous solution shear viscosity, bounded by the pure solvent viscosity and that of the bulk micellar solution. For 0.1 and 0.2-M sodium dodecylsulfate micellar solutions, the effective viscosities are less than 5 and 10%, respectively, below the homogeneous fluid viscosity, except at small thicknesses, indicating that the micellar film thins faster than a pure water film of the same thickness. Calculated thinning curves closely resemble experimental observations in the stepwise thinning behavior, displaying decreasing slopes and increased step durations at later times. Despite the micellar structuring within the film, the ionic micelles do not contribute appreciably to the viscous resistance of the thinning film. Rather, Reynolds' film thinning is obeyed, with the equilibrium oscillatory disjoining pressures driving the stepwise dynamics. The shear viscosity of the ionic micellar film is well approximated by that of the bulk solution.
A Giant Cell with Dendritic Cell Properties in Spleens of the Anuran Amphibian Xenopus Laevis

Abstract Numerous large, mitotically active cells with abundant electron lucent cytoplasm, large hyperlobated nuclei and prominent nucleoli are found in the periphery of the splenic white pulp follicles of healthy Xenopus laevis . Like mammalian dendritic cells, these cells are located in B-lymphocyte-rich splenic follicles and have long cytoplasmic processes that are in intimate contact with adjacent lymphocytes. Some of the cytoplasmic processes extend through the Tlymphocyte-rich marginal zone into red pulp and appear to trap and transport foreign material (colloidal carbon and human IgG) from its initial site of entry in the splenic red pulp into the white pulp. In contrast to macrophages, these cells do not phagocytose large quantities of carbon. They also fail to stain for the non-specific esterase, either in a diffuse pattern characteristic for macrophages or in the punctate pattern found in most lymphoid cells in this species. In contrast to adjacent B-lymphocytes in the white pulp follicle, they do not stain for cytoplasmic Ig. Unlike T-lymphocytes, early thymectomy does not interfere with their development (1). Thus, this cell may well be a primitive follicular dendritic cell. If so, it offers insights into the function of the Xenopus spleen, and the phylogenetic origin of dendritic cells.
The impact of interannual rainfall variability on the spatial and temporal patterns of vegetation in a water-limited ecosystem

Abstract A hydrologically driven hierarchical competition–colonization model is applied in an spatially explicit manner to investigate the effect of temporal (e.g., interannual rainfall fluctuations) and spatial (e.g., local dispersal) processes on vegetation patterns. Results suggest that interannual rainfall fluctuations extend the range of dispersal distances that result in spatial organization (e.g., clustering, self-similarity) and proportional abundances of vegetation different from those expected for the globally dispersing case.
Autumnal production by bacteria and autotrophs attached to Typha latifolia L. Detritus

ABSTRACT From Typha latifolia detrital samples incubated in a natural wetland, both bacterial production and photosynthetic production, as well as chlorophyll mass, autotroph biovolume and rate of detritus decay, were determined under shaded and unshaded (full-sun) conditions over a 60-day interval during autumn. Bacterial biomass productivity (BBP) and algal/cyanobacterial photosynthesis on the field-incubated detritus were measured in the laboratory over a gradient of photon flux density (PFD: 0—500 μmol m−2 s−1) by use of a light pipetting apparatus. Estimates of chlorophyll regimes and carbon fixation indicated a pattern of physiological adjustment by algae and cyanobacteria to the prevailing light intensity in the field treatments. Under shaded conditions, chlorophyll mass was as much as three times greater than the mass under unshaded conditions, yet there were no apparent differences in autotroph biovolume; additionally, total chlorophyll-derived pigments (chlorophyll a + phaeophytin) were consiste...
Synergistic stimulation of amnion cell prostaglandin E2 synthesis by interleukin-1, tumor necrosis factor and products from activated human granulocytes.

Abstract We examined the interactions between supernatant from FMLP-activated human granulocytes, recombinant interleukin-1 (IL-1) and recombinant tumor necrosis factor (TNF) in the stimulation of prostaglandin E 2 (PGE 2 ) production by human amnion cells. Amnion cells from elective term cesarian sections were cultured in monolayer culture. Human granulocytes were activated with FMLP and centrifuged to obtain cell-free supernatant. Amnion cells were treated with granulocyte supernatant, IL-1α, IL-1β, TNF-α, TNF-β, or different combinations of these. Each of the stimulators alone enhanced the PGE 2 production 5-to 27-fold. Granulocyte supernatant was synergistic with each of the cytokines. The combinations of IL-1α or IL-1β with either TNF-α or TNF-β caused a synergistic stimulation of amnion cell PGE 2 production as well, whereas the combinations of IL-1α with IL-1β or of TNF-β with TNF-β were not synergistic. Furthermore, granulocyte supernatant was synergistic with the combination of IL-1 and TNF, resulting in a more than 150-fold stimulation of PGE 2 production. Indomethacin completely suppressed these effects. We propose that granulocyte products acting together with IL-1 and TNF enhance PGE 2 synthesis during inflammation, and serve as signals for the initiation of preterm labor in the setting of intra-amniotic infection.
A rapid, novel model of culturing cranial nerve X-derived motoneurons for screening trophic factor outgrowth response

Objectives: After cranial nerve X (CN X) injury, vocal fold paralysis treatments currently face a myriad of obstacles in achieving non-synkinetic, functional reinnervation. Of particular therapeutic interest is the targeted administration of locally expressed biological neurotrophic factors (NFs). To date, a method to culture mature CN X motoneurons for NF responsiveness screening has not been described. Methods: We herein present a novel method for establishing mature murine CN X motoneuron cultures, and use the model to test CN X motoneuron outgrowth response to individual and paired ascending concentrations of selected neurotrophic factors [glial cell-derived neurotrophic factor (GDNF), brain-derived neurotrophic factor (BDNF), and ciliary neurotrophic factor (CNTF)]. Results: Findings demonstrated low concentration (5 ng/ml) CNTF to have the greatest positive effect on motoneuron outgrowth, beyond that of both indivual NF and paired NF combinations, based on total neurite outgrowth [mean total neurite...
Multinationality and Common Stock Offering Dilution

This study examines the common stock offering dilution of multinational and domestic firms. Results provide evidence that the benefits of multinationality do not offset the negative information effect of perceived cash flow shortfalls at the announcement of security offerings. MNCs and purely domestic firms experience comparable negative valuation and offering dilution at the announcement of a common stock offering. These results are independent of size and performance differences between multinational and domestic firms at the announcement year.
An evolutionary view of human recombination

Recombination has essential functions in mammalian meiosis, which impose several constraints on the recombination process. However, recent studies have shown that, in spite of these roles, recombination rates vary tremendously among humans, and show marked differences between humans and closely related species. These findings provide important insights into the determinants of recombination rates and raise new questions about the selective pressures that affect recombination over different genomic scales, with implications for human genetics and evolutionary biology.
Ultrawideband coplanar waveguide-fed tapered slot line antenna

This paper reports the development of an ultra-wide slotline antenna. The antenna is fed using a broad-band coplanar waveguide-to-slotline transition. A return loss of better than 10 dB over a very wide bandwidth of 0.5 to 6 GHz has been measured. Typical measured gain is 8 dBi at 5 GHz. As the antenna can easily be scaled for operations at millimeter and submillimeter wavelengths, its achieved extremely wide bandwidth demonstrates the potential for ultra-wide- band applications in these regimes.
Low Brain Magnesium in Migraine

Brain magnesium was measured in migraine patients and control subjects using in vivo 31-Phosphorus Nuclear Magnetic Resonance Spectroscopy. pMg and pH were calculated from the chemical shifts between Pi, PCr and ATP signals. Magnesium levels were low during a migraine attack without changes in pH. We hypothesize that low brain magnesium is an important factor in the mechanism of the migraine attack.
Measurements of Gas Velocities and Temperatures in a Large Open Pool Fire

A number of measurements were made to help define the thermal and flow conditions in a 9 × 18 meter pool fire that was used to simulate a transportation accident. Temperatures were measured at twenty-eight locations throughout the continuous flame region. Velocities were measured at four vertical stations near the centerline of the pool. Heat fluxes were estimated from thermal measurements on and near vertical steel plates. As is often the case in fires of this size, the effects of mild, ambient winds on the measurements were pronounced. Attempts have been made to mitigate these effects by the application of conditional sampling. Temperatures and velocities are compared with other experimental results as well as results of modeling efforts.
Short amino acid sequences derived from C1q receptor (C1q-R) show homology with the alpha chains of fibronectin and vitronectin receptors and collagen type IV.

The human Clq receptor (Clq-R) is a 65-70-kd, highly acidic, hydrophobic glycoprotein that is expressed on a wide variety of cell surfaces. Although the Clq-R itself appears to bind preferentially to Clq, the region of the ligand to which Clq-R binds is the primary binding site for several other molecules, including fibronectin, laminin, and Clq inhibitor (chondroitin 4-sulfate proteoglycan) as well as the complement Clr2Cls2 tetramer. In order to further characterize the Clq-R molecule with regard to its structure and function, highly purified Clq-R was obtained from Raji cells using DEAE-Sephacel and Clq-Sepharose CL-4B chromatogra- phy. Studies performed with '25I-labeled Clq-R demon- strated that whereas the Clq-R molecule binds poorly to a variety of human collagens including types II, III, and v, markedly enhanced binding is observed with type IV collagen and moderately enhanced binding with type I collagen. Amino acid composition studies show that the Clq-R molecule contains approximately 44% hydropho- bic and 12.6% hydrophiic residues with a ratio of nega- tively charged to positively charged residues of about 2:1. Treatment of 125I-labeled Clq-R with endoglycosidase F lowers the apparent molecular size from 70 to 58 kd, whereas endoglycosidase H lowered the size to 64 kd. Treatment with neuraminidase, on the other hand, shifted the size of Clq-R to 60 kd. These results suggest the presence of several highly sialylated complex-type or high mannose-type N-linked oligosaccharide side chains. Because purified Clq-R has a blocked amino terminus, amino acid sequences representing internal fragments of the molecule were generated by electroblotting and in situ enzymatic digestion. When these short sequences were searched against the National Biomedical Research Foun- dation computer data base, a seven-amino-acid sequence, VSWQGQI, showed significant homology (100% and 80% in a five-amino-acid overlap, respectively) with the a chains of the human fibronectin (a5131) and vitronectin ( a"f33) receptors, and to a lesser degree with epidermal growth factor receptor and T cell receptor. A second se- quence, ISEDNIR, showed homology with mouse colla- gen type IV (86% in a six-amino-acid overlap), calmodu- lin (60% in a seven-amino-acid overlap), and a Leishmania major surface antigen, gp63. These observa- tions seem to predict that Clq-R has pockets of conserved sequences that are similar to those not only present in its ligand(s) but also in other cell surface receptors that may, in part, fulfill similar functions. J. Leukoc. Biol. 51: 546-556; 1992.