cssi/SciSciGPT-SciSciNet huggingface dataset:
Teaching strategies and activities that enhance spatial visualization

Russell and Nicole are working together on a project in their seventh grade mathematics class. Mrs. Jones, their teacher, asks them to count the number of squares that they can find on a standard 8 by 8 chessboard. Nicole has limited prior experiences with activities such as these, but she easily counts all the small squares and concludes that 64 is the total number of the squares on the 8 by 8 chessboard (or checkerboard). Russell, on the other hand, had played on his Nintendo and Game Boy for five years and was also a self-proclaimed expert at the game of Tetris. In addition to the 64 squares that Nicole found, Russell tells Mrs. Jones that there are additional squares formed by groups of the small squares. Nicole just did not "see" these other squares on her first count. Scenarios like these occur frequently in mathematics classrooms where students are developing the foundation required for higher levels of mathematics. It is important that teachers find ways to enhance students' spatial sense not only for future success in mathematics but also to enhance students' interests and talents in maths-related fields such as the physical sciences, architecture, computer-aided design, geographic information systems, and graphic design (Allen, 2003; Lury & Massey, 1999; Mark & Egenhofer, 1994).
On ω-controllability and ω-normality of deds

In this paper, we address the supervisory synthesis problem for controlling the sequential behaviors of Discrete Event Dynamical Systems (DEDS's) under complete as well as partial information through the use of synchronous composition of the plants and the supervisors [7], [12]. We present the notion of complete languages and show its close relation to ω-languages. We prove that the supremal (closed,) complete and controllable sublanguage of a given language exists and present an algorithm to compute it. We present a closed form expression for the supremal ω-controllable sublanguage of a given ω-language in terms of the supremal (closed,) complete and controllable sublanguge. The notions of ω-observability and ω-normality are introduced. A necessary and sufficient condition for the existence of a supervisor in case of partial observation is presented in terms of ω-observability. A closed form expression for the supremal ω-normal sublanguage in terms of the supremal closed, complete and normal sublanguage is also presented.
Speech Recognition, Automatic

Automatic speech recognition is the attempt to use a machine to derive the linguistic message from a speech signal. Keywords: speech recognition; machine learning; acoustic processing; feature extraction; hidden Markov model; human–machine communication
Computer alerts for potassium testing: resisting the temptation of a blanket approach.

In the Nov/Dec, 2003 issue of JAMIA , Hoch et al1 have reported the effectiveness of computer alerts to improve potassium testing in patients receiving diuretics. The underlying hypothesis of the study was that diuretics can cause hypokalemia, which can lead to adverse drug events (ADEs) including atrial and ventricular arrhythmias. The authors suggest that computer alerts to physicians would increase the rate of annual potassium testing for patients on diuretics, which would, in turn, prevent such ADEs. However, we wish to draw readers' attention to the following details. First, it is conceivable that physicians deliberately decided not to test their patients annually based on their clinical judgment. The patients might have had stable serum potassium levels for many years or may have been asked to follow a high-potassium diet. Hence, the physicians may have changed behavior to avoid repeat alerts and not solely on …
3D PIC simulation study of the relativistic magnetron

Summary form only given. The magnetron is intrinsically a 3D problem. 3D simulation is required to obtain the correct electromagnetic fields and realistically model power extraction, for example. We have used the 3D PIC code QUICKSILVER to perform a simulation study of the Palevsky/Bekefi A6 magnetron experiments. The latter serve as somewhat of a benchmark for modeling this complicated tube. We discuss the results of this study, which are consistent with experimental observations. The simulations reveal details of phenomena that are not directly observable in experiments, such as efficiency loss due to current leakage along magnetic field lines and self insulation effects. Techniques for solving these problems are presented. Results of this study suggest that a different tube configuration may be necessary to obtain high efficiency from a relativistic magnetron.
The Plasticity of Poetry

This essay won the 2005 Literature Compass Graduate Essay Prize, Twentieth Century Section. By comparing avant-garde visual poetry to the avant-garde architecture of Arakawa and Madeline Gins, this essay describes how one virtually “moves through” poetic space. Appealing to examples from L=A=N=G=U=A=G=E poets Charles Bernstein, Steve McCaffery and Susan Howe and contemporary Chilean poet Cecilia Vicuna, I steer the reader through complex visual poems based on the grounds that a disruption of the reader’s sense of space has aesthetic and political implications.
Basic principles of ROC analysis

The limitations of diagnostic "accuracy" as a measure of decision performance require introduction of the concepts of the "sensitivity" and "specificity" of a diagnostic test. These measures and the related indices, "true positive fraction" and "false positive fraction," are more meaningful than "accuracy," yet do not provide a unique description of diagnostic performance because they depend on the arbitrary selection of a decision threshold. The receiver operating characteristic (ROC) curve is shown to be a simple yet complete empirical description of this decision threshold effect, indicating all possible combinations of the relative frequencies of the various kinds of correct and incorrect decisions. Practical experimental techniques for measuring ROC curves are described, and the issues of case selection and curve-fitting are discussed briefly. Possible generalizations of conventional ROC analysis to account for decision performance in complex diagnostic tasks are indicated. ROC analysis is shown to be related in a direct and natural way to cost/benefit analysis of diagnostic decision making. The concepts of "average diagnostic cost" and "average net benefit" are developed and used to identify the optimal compromise among various kinds of diagnostic error. Finally, the way in which ROC analysis can be employed to optimize diagnostic strategies is suggested.
The Annexin A2/p11 complex is required for efficient invasion of Salmonella Typhimurium in epithelial cells.

Summary The facultative intracellular pathogen, Salmonella enterica, triggers its own uptake into non-phagocytic epithelial cells. Invasion is dependent on a type 3 secretion system (T3SS), which delivers a cohort of effector proteins across the plasma membrane where they induce dynamic actin-driven ruffling of the membrane and ultimately, internalization of the bacteria into a modified phagosome. In eukaryotic cells, the calcium- and phospholipid-binding protein Annexin A2 (AnxA2) functions as a platform for actin remodelling in the vicinity of dynamic cellular membranes. AnxA2 is mostly found in a stable heterotetramer, with p11, which can interact with other proteins such as the giant phosphoprotein AHNAK. We show here that AnxA2, p11 and AHNAK are required for T3SS-mediated Salmonella invasion of cultured epithelial cells and that the T3SS effector SopB is required for recruitment of AnxA2 and AHNAK to Salmonella invasion sites. Altogether this work shows that, in addition to targeting Rho-family GTPases, Salmonella can intersect the host cell actin pathway via AnxA2.
An improved method for the measurement of malondialdehyde in biological samples

An improved method was developed for measuring malondialdehyde (MDA) as its thiobarbituric acid (TBA) complex. Samples were initially incubated with 1% potassium iodide and 0.1% butylated hydroxytoluene at 50°C for 20 min, and then with 0.4% TBA at 60°C for 60 min. The MDA-TBA complex formed was extracted with isobutyl alcohol and measured by high-performance liquid chromatography with fluorescence detection. The improved method allows for a more specific determination of MDA present in biological samples.
Arithmetic achievement as a function of introversion-extraversion and teacher-presented reward and punishment☆

Abstract Following Eysenck (1967), Gray (1973) and Wakefield (1979), it was hypothesized that the arithmetic achievement of extraverts would be better than introverts in those classrooms in which teacher-presented rewards predominated, and the arithmetic achievement of introverts would be better than extraverts in those classrooms in which teacher-presented punishment predominated. Five classrooms were rank-ordered according to their ratios of teacher-presented reward to teacher-presented punishment. A total of 101 fourth and fifth grade students from the five classrooms were then administered the Junior Eysenck Personality Questionnaire (JEPQ) and an arithmetic pretest. Subsequent to 40 school days, the students were administered the arithmetic posttest. Partialling out arithmetic pretest scores, lie scale scores from the JEPQ, and total arithmetic raw scores from the Comprehensive Test of Basic Skills (CTBS), regression analysis of arithmetic posttest scores with the interaction of extraversion scores from the JEPQ and classroom rank-order of the ratio of teacher-presented reward to teacher-presented punishment yielded significant results supporting the hypothesis. Additional analysis indicated the presence of non-hypothesized interactions of the Psychoticism and Neuroticism scales of the JEPQ with reward-punishment and extraversion.
Lightening the Load: An Exploratory Analysis of Divestiture Strategies of Major Media Firms

AbstractThe Telecommunications Act of 1996 has encouraged media firms to restructure their operations, relative to new opportunities. The deregulatory law has led firms to engage in extensive mergers and acquisitions. Similarly, media firms have divested numerous operations. The goal of this exploratory research article is to ascertain the divestiture strategies—and divestiture determinants—of major media firms since the Telecommunications Act of 1996. Divestiture strategies and motivations were reviewed and applied to recent media divestiture activity.
New multilevel codes over GF(q)

Set partitioning is applied to multidimensional signal spaces over GF(q), i.e., GF/sup n1/(q) (n1 or=d are presented. These codes use Reed-Solomon codes as component codes. Longer multilevel block codes are also constructed using q-ary block codes with block length longer than q+1 as component codes. Some quaternary multilevel block codes are presented with the same length and number of information symbols as, but larger distance than, the best previously known quaternary one-level block codes. It is proved that if all the component block codes are linear. the multilevel block code is also linear. Low-rate q-ary convolutional codes, word-error-correcting convolutional codes, and binary-to-q-ary convolutional codes can also be used to construct multilevel trellis codes over GF(q) or binary-to-q-ary trellis codes. >
Dazed and confused by HHV-6.

Human herpesvirus 6 (HHV-6) is recognized as a sporadic cause of encephalitis in hematopoietic cell transplantation (HCT) recipients. In this issue of Blood, Zerr and coworkers report on a 3.5-year prospective study of 315 patients undergoing allogeneic HCT. 1 Patients with HHV-6 were more likely to develop delirium and neurocognitive decline. The results support a future clinical trial to test whether antiviral prophylaxis will reduce CNS morbidity after HCT.
THE HELICOBACTER PYLORI 16S rRNA GENE PCR WITH THE PRIMER SET HP1/HP2 AMPLIFYING A 109-bp FRAGMENT IS NOT SPECIFIC AND CANNOT BE USED TO DETECT H. PYLORI IN CLINICAL SPECIMENS. † 686

THE HELICOBACTER PYLORI 16S rRNA GENE PCR WITH THE PRIMER SET HP1/HP2 AMPLIFYING A 109-bp FRAGMENT IS NOT SPECIFIC AND CANNOT BE USED TO DETECT H. PYLORI IN CLINICAL SPECIMENS. † 686
In the shadow of whiteness: (re)exploring connections between history, enacted culture, and identity in a digital divide initiative

Who we are, our identities, as educators and learners cannot be considered separately from our histories and cultures. As such, many attempts at improving education for historically marginalized minority groups often revolve around finding ways to connect youth culture to curricula. What remains largely unexamined, however, are the history, culture, and identities of White educators and how these forces necessarily impact the ways in which curricula are designed for youth of color. By reconsidering DeGennaro and Brown’s article “Youth Voices: Exploring Connections between History, Enacted Culture and Identity in a Digital Divide Initiative” through a lens of Whiteness, this article aims to illustrate that the histories and identities of African–American learners are dialectically related to the histories and identities of White educators. However, because Whiteness tends to be invisible, White educators have the privilege of not examining who they are and where they come from as part of their own identity development during the teaching and learning process. This article invites White educators to question what it means to educate youth of color by recognizing their own Whiteness as a powerful force in shaping pedagogical activities. By understanding both themselves and their students as racialized, cultural actors, White educators can begin to develop curricula that are truly empowering for minority youth.
Adsorption Mechanisms and Effect of Temperature in Reversed-Phase Liquid Chromatography. Meaning of the Classical Van't Hoff Plot in Chromatography

The effect of temperature on the adsorption and retention behaviors of a low molecular weight compound (phenol) on a C18-bonded silica column (C18-Sunfire, Waters) from aqueous solutions of methanol (20%) or acetonitrile (15%) was investigated. The results of the measurements were interpreted successively on the basis of the linear (i.e., overall retention factors) and the nonlinear (i.e., adsorption isotherms, surface heterogeneity, saturation capacities, and equilibrium constants) chromatographic methods. The confrontation of these two approaches confirmed the impossibility of a sound physical interpretation of the conventional Van’t Hoff plot. The classical linear chromatography theory assumes that retention is determined by the equilibrium thermodynamics of analytes between a homogeneous stationary phase and a homogeneous mobile phase (although there may be two or several types of interactions). From values of the experimental retention factors in a temperature interval and estimates of the activity c...
Fundus Image Processing System For Early Detection Of Glaucoma

An image processing system based on a MC 68000 microprocessor has been developed for analysis of fundus photographs. This personal computer based system has specific image enhancement capabilities comparable to existing large scale systems. Basic enhancement of fundus images consists of histogram modification or kernel convolution techniques to determine regions of specific interest such as textural difference in the nerve fiber layer or cupping of the optic nerve head. Fast Fourier transforms and filtering techniques are then utilized for specific regions of the original image. Textural difference in the nerve fiber layers are further highlighted using either interactive histogram modification or pseudocolor mappings. Menu driven software allows review of the steps applied, creating a feedback mechanism for optimum display of the fundus image. A wider noise margin than that of digitized fundus photographs can be obtained by direct fundus imaging. The present fundus image processing system clearly provides us with quantitative and detailed techniques of assessing textural changes in the fundus photographs of glaucoma patients and suspects for better classification and early detection of glaucoma. The versatility and computing capability of the system make it also suitable for other applications such as multidimensional image processing and image analysis.
Microscopic tubes in igneous rocks

Microscopic tubes have been observed in several igneous rocks and may be quite common. They occur in single crystals and have either elliptical or circular cross-sections 1 to 5 microns in diameter and are ten to hundreds of microns long. Microtubes may be hollow or partially or completely filled with another phase, but are distinct from acicular crystals of accessory minerals such as rutile. Microtubes can form by at least three processes: (1) the partial annealing of microcracks, (2) the natural etching of dislocations, or (3) the primary inclusion of fluid material during crystal growth.
Analysis of intermediate structure in terms of level-parameter statistics

Abstract Intermediate structure observed in the neutron total cross sections of Mo and Sn is discussed in terms of expected statistical fluctuations of the widths and spacings of compound-nucleus levels. Although the observed amplitude of this structure can be explained by such fluctuations, the data show correlations that are significantly inconsistent with this interpretation.
Maternal Placental Blood Flow Is Reduced in Proportion to Reduction in Uterine Driving Pressure

ABSTRACT: The relationship between uterine driving pressure and maternal placental blood flow was studied after inflation of an aortic occluder previously placed between the renal and ovarian arteries in 10 conscious pregnant rabbits at 28 ± 1 (mean ± SEM) d of a 30− to 31-d gestation to test the hypothesis that there is autoregulation of maternal placental blood flow. After control measurements, the femoral artery pressure was reduced 22 ± 3% from 83 ± 5 mm Hg and clamped at 65 ± 4 mm Hg (p < 0.001) for 54 ± 4 min by servo control. Carotid artery pressure increased from 86 ± 5 to 98 ± 6 mm Hg (p < 0.01). There was no change in cardiac output (839 ± 78 vs 814 ± 64 mL/min; NS), upper-body flow (651 ± 62 vs 671 ± 55 mL/min; NS), or renal flow (111 ± 14 vs 104 ± 8 mL/min; NS). Blood flow to tissues below the occluder decreased from 188 ± 18 to 143 ± 14 mL/min for the lower body (p < 0.05), 153 ± 15 to 116 ± 11 mL/min for the hindquarters (p < 0.05), and 17.7 ± 1.9 to 12.9 ± 1.4 mL/min for 13 pregnant uterine horns (p < 0.05). Placental flow to live fetuses per horn decreased from 13.0 ± 1.9 to 8.9 ± 1.2 mL/min (p < 0.01), whereas there was no significant change in myoendometrial flow (4.0 ± 0.3 vs 3.5 ± 0.5 mL/min; NS). Uterine oxygen consumption was unchanged (1.15 ± 0.16 vs 1.06 ± 0.13 mL/min; NS). There was no change in the circulating arterial concentration of angioten sin I (2.95 ± 1.07 vs 1.46 ± 0.59 ng · mL−1) or active plasma renin activity (8.83 ± 3.72 vs 10.70 ± 5.56 ng · mL−1 · h−1), but trypsin-activated total plasma renin activity increased from 20.24 ± 2.39 to 27.34 ± 5.33 ng · mL−1 · h−1 (p < 0.05). There was neither a uterine venoarterious difference nor a net uterine release of angiotensin I or active plasma renin activity at any time, but the net uterine release of total plasma renin activity increased from 31.66 ±24.08 to 72.32 ± 19.46 (ng · mL−1 · h−1)-(mL # min−1) (p < 0.05). We conclude that there is no significant autoregulation of placental blood flow in the first hour after reduction in uterine driving pressure in the conscious pregnant rabbit. Uterine hypotension is associated with an increase in arterial pressure above the occluder and with the release of an inactive form of renin from the uterus. The significance of the latter two findings remains conjectural.
Effects of Coster-Kronig transitions on electron-impact excitation rates for fluorinelike ions in their ground states

The contributions of Coster-Kronig resonances to the electron-impact excitation rate coefficients have been calculated for six F-like ions with {ital Z}=26, 34, 42, 47, 54, and 63. The calculations are carried out using the relativistic distorted-wave approximation and the multiconfiguration Dirac-Fock model. We found that resonance excitation via Coster-Kronig transitions is the dominant excitation mechanism at low temperatures for {ital Z}{le}34 and is as important as the direct excitation for heavier ions. In addition, we found that the effects of relativity can reduce the rate coefficients by more than an order of magnitude at electron temperatures {ital T}{lt}100 eV.
Vitamins and exercise--an update.

BELKO, A. Z. Vitamins and exercise—an update. Med. Sci. Sports Exerc., Vol. 19, No. 5 (Supplement), pp. S191–S196, 1987. Although no conclusive evidence exists to suggest that vitamin supplementation improves athletic performance in nutritionally adequate individuals, exercise may increase requirements for certain vitamins in individuals with marginal vitamin stores. This review summarizes results from recent research studies of vitamins and exercise. Exercise increased the requirement for riboflavin and vitamin C; however, vitamin supplementation improved the ability to train only in vitamin C-depleted individuals. No measurable effect of supplemental thiamin, riboflavin, or vitamin B6 on performance was observed in any of the reported studies. Exercise acutely affected vitamin B6 metabolism. Confusion regarding vitamin supplementation and exercise performance may stem from a lack of adequate research data. Recommendations for future research are presented.
Ultrastructure of the post–corpus of Zeldia punctata (Cephalobina) for analysis of the evolutionary framework of nematodes related to Caenorhabditis elegans (Rhabditina)

The ultrastructure of the post-corpus of Zeldia punctata (Cephalobina) was compared with previous observations of Caenorhabditis elegans (Rhabditina) and Diplenteron sp. (Diplogastrina) with the goal of interpreting the morphological evolution of the feeding structures in the Secernentea. The post-corpus of Z. punctata consists of six marginal, 13 muscle, five gland and seven nerve cells. The most anterior of four layers of muscle cells consists of six mononucleate cells in Z. punctata. The homologous layer in C. elegans and Diplenteron consists of three binucleate cells, suggesting a unique derived character (synapomorphy) shared between the Rhabditina and Diplogastrina. Contrary to Diplenteron sp. where we observed three oesophageal glands, Z. punctata and C. elegans have five oesophageal glands. We question this shared character as reflecting a common evolution between the Cephalobina and Rhabditina, because there are strong arguments for functional (adaptive) convergence of the five glands in these bacterial feeders. Convergence is further suggested by the mosaic distribution of three versus five glands throughout the Nemata; this distribution creates difficulties in establishing character polarity. Although morphological data are often laborious to recover and interpret, we nevertheless view 'reciprocal illumination' between molecular and morphological characters as the most promising and robust process for reconstructing the evolution of the Secernentea and its feeding structures.
Complementarity and Fundamental Limit in Precision Phase Measurement.

By analyzing a single-photon interference experiment together with a quantum nondemolition measurement scheme for the which-path information, we prove that given the total mean number $〈n〉$ of available photons, the fundamental limit in precision measurement of a phase shift is the Heisenberg limit, i.e., $1/〈n〉$. The analysis is based on the complementarity principle and is independent of the scheme for the measurement of the phase shift. We also show that to achieve the Heisenberg limit states with photon number fluctuations of the order of or larger than the mean photon number have to be exploited.
Low-Energy Operation of the Lawrence Livermore Electron Beam Ion Traps: Atomic Spectroscopy of Si V, S VII and Ar IX

As part of a project to compile a comprehensive catalog of astrophysically relevant emission lines, we used the low-energy capability of the Lawrence Livermore electron beam ion traps to extend the spectroscopy of neon-like ions and the neighboring charge states to silicon, sulfur, and argon. They present wavelength data of Si V and demonstrate the effect of collisional deexcitation of electric dipole forbidden lines on the 2-3 L-shell spectra of Si V, S VII, and Ar IX.
Some new and short proofs for a class of Caffarelli-Kohn-Nirenberg type inequalities

Abstract In this note we provide simple and short proofs for a class of inequalities of Caffarelli–Kohn–Nirenberg type with sharp constants. Our approach suggests some definitions of weighted Sobolev spaces and their embedding into weighted L 2 spaces. These may be useful in studying solvability of problems involving new singular PDEs.
Clinical Profiles Associated with Influenza Disease in the Ferret Model

Influenza A viruses continue to pose a threat to human health; thus, various vaccines and prophylaxis continue to be developed. Testing of these products requires various animal models including mice, guinea pigs, and ferrets. However, because ferrets are naturally susceptible to infection with human influenza viruses and because the disease state resembles that of human influenza, these animals have been widely used as a model to study influenza virus pathogenesis. In this report, a statistical analysis was performed to evaluate data involving 269 ferrets infected with seasonal influenza, swine influenza, and highly pathogenic avian influenza (HPAI) from 16 different studies over a five year period. The aim of the analyses was to better qualify the ferret model by identifying relationships among important animal model parameters (endpoints) and variables of interest, which include survival, time-to-death, changes in body temperature and weight, and nasal wash samples containing virus, in addition to significant changes from baseline in selected hematology and clinical chemistry parameters. The results demonstrate that a disease clinical profile, consisting of various changes in the biological parameters tested, is associated with various influenza A infections in ferrets. Additionally, the analysis yielded correlates of protection associated with HPAI disease in ferrets. In all, the results from this study further validate the use of the ferret as a model to study influenza A pathology and to evaluate product efficacy.
Mixed variational principles in non-linear electroelasticity

Abstract We discuss several mixed variational principles which generalize existing vanational principles in the non-linear theory of electroelasticity.
Environmental Scanning Practices for Rural Colleges.

Enviroiimental scanning allows rural community colleges to forecast change, identify implications for the organization, and plan preferred responses to shape thefuture.
Children's social behaviors as predictors of academic achievement: A longitudinal analysis.

This study was an investigation of the relationships among a diverse sample of elementary students’ social skills, problem behaviors, academic competence, and academic achievement. The primary research question addressed the relationship between social behaviors and academic achievement. All data were collected and examined at two timepoints within a school year, which allowed for a replication of the relationships among the variables and an investigation of the predictive relationships over time. The participants in this study were 139 third- and fourth-grade students, and their teachers, from two schools in a large urban community in western Massachusetts. The results of this study indicated that (a) social skills are positively predictive of concurrent levels of academic achievement and (b) problem behaviors are negatively predictive of concurrent academic achievement. Only social skills, however, emerged as a significant predictor of future academic functioning. The linkage between problem behaviors and future academic performance may vary as a function of ethnic or cultural membership status. In schools across the United States, positive social behavior, academic competence, and high levels of achievement are objectives valued by teachers, parents, and other educational stakeholders. Given these valued objectives of education, it is surprising to find that many stakeholders are concerned that interventions focusing on students’ social behavior may diminish or shortchange the development of academic outcomes. This perception is most likely because of the belief that time will be taken away from academics if social behaviors are given a prominent place in instruction. Researchers suggest, however, that there is a strong relationship between social behavior and academic achievement (DiPerna & Elliott, 1999; Feshbach & Feshbach, 1987; Green, Forehand, Beck, & Vosk, 1980; Gresham & Elliott, 1990; Lambert & Nicholl, 1977; Wentzel, 1991,
A DISTRIBUTED AUTOMATION FRAMEWORK FOR PLANT-WIDE CONTROL, OPTIMISATION, SCHEDULING AND PLANNING

Abstract The objective of the talk will be to identify current open problems and trends in plant wide control and demonstrate a solution based on distributed, solution component based architecture for integrated process management, embracing the layers of Advanced Process Control, Real Time Optimisation and Planning & Scheduling, in selected application areas. The problems and outlined solutions are intended to stimulate discussion as well as attract more research interest.
Dynamics of Coupled Noisy Neural Oscillators with Heterogeneous Phase Resetting Curves

Pulse-coupled phase oscillators have been utilized in a variety of contexts. Motivated by neuroscience, we study a network of pulse-coupled phase oscillators receiving independent and correlated noise. An additional physiological attribute, heterogeneity, is incorporated in the phase-resetting curve (PRC), which is a vital entity for modeling the biophysical dynamics of oscillators. An accurate probability density or mean field description is large-dimensional, requiring reduction methods for tractability. We present a reduction method to capture the pairwise synchrony via the probability density of the phase differences, and we explore the robustness of the method. We find the reduced methods can capture some of the synchronous dynamics in these networks. The variance of the noisy period (or spike times) in this network is also considered. In particular, we find that phase oscillators with predominately positive PRCs (type I) have larger variance with inhibitory pulse-coupling than PRCs with a larger neg...
Determination of a novel thrombin inhibitor in human plasma and urine utilizing liquid chromatography with tandem mass spectrometric and ultraviolet detection

Abstract An LC–MS–MS method and an HPLC–UV method have been developed for the assay of a novel thrombin inhibitor in human fluids. The LC–MS–MS method is developed for plasma, which usually requires maximum sensitivity. The HPLC–UV method is for urine. In both methods, analytes are extracted using liquid–liquid extraction, and analyzed by reversed-phase high-performance liquid chromatography. A tandem mass spectrometer in the multiple reaction monitoring (MRM) mode is used for detection of the analytes in the plasma method. UV is the detector for the urine method. The plasma method has a lower limit of quantitation (LOQ) of 0.1 ng/ml with a linearity range of 0.1–100 ng/ml. The urine method has an LOQ of 8.12 ng/ml (20 nM) and the linear dynamic range is 8.12–8120 ng/ml (20–20 000 nM). Both methods are fast, specific and sensitive. Various validation procedures have proven that both methods are rugged, robust and reproducible. The research also suggested that, while LC–MS–MS provides superior sensitivity and selectivity for the determination of drugs and their metabolites at very low concentrations, HPLC with a conventional detector such as UV is still useful in the analysis when the sensitivity requirement is not crucial.
Object Manipulation Improvements Due to Single Session Training Outweigh the Differences Among Stimulation Sites During Vibrotactile Feedback

Most hand prostheses do not provide intentional haptic feedback about movement performance; thus users must rely almost completely on visual feedback. This paper focuses on understanding the effects of learning and different stimulation sites when vibrotactile stimulation is used as the intentional haptic feedback. Eighteen unimpaired individuals participated in this study with a robotic interface to manipulate a virtual object with visual and vibrotactile feedback at four body sites (finger, arm, neck, and foot) presented in a random order. All participants showed improvements in object manipulation performance with the addition of vibrotactile feedback. Specifically, performance showed a strong learning effect across time, with learning transferring across different sites of vibrotactile stimulation. The effects of learning over the experiment overshadowed the effects of different stimulation sites. The addition of a cognitive task slowed participants and increased the subjective difficulty. User preference ratings showed no difference in their preference among vibrotactile stimulation sites. These findings indicate that the stimulation site may not be as critical as ensuring adequate training with vibrotactile feedback during object manipulation. Future research to identify improvements in vibrotactile-based feedback parameters with amputees is warranted.
Simian Immunodeficiency Virus

Survey of Simian Immunodeficiency Virus Among Nonhuman Primate Populations.- Simian Immunodeficiency Viruses of African Green Monkeys.- Pathology of Simian Immunodeficiency Virus Induced Disease.- SIVsmmPBj14: An Atypical Lentivirus.- Conserved Framework of Envelope Glycoproteins Among Lentiviruses.- Mucosal Transmission of Simian Immunodeficiency Virus.- Comparisons of Regulatory Features Among Primate Lentiviruses.- MHC of Nonhuman Primates.- CD4+ T Cell Responses to Simian Immunodeficiency Virus.- The SIVmac Specific Cytotoxic T Lymphocyte Response in the Acutely Infected Rhesus Monkey.- Envelope Sequence Variation, Neutralizing Antibodies, and Primate Lentivirus Persistence.- Towards a Vaccine Against AIDS: Lessons from Simian Immunodeficiency Virus Vaccines.
Virtual reference services: Implementation of professional and ethical standards

Virtual reference, which allows users to connect easily with librarians online, is becoming popular. Librarians answer thousands of questions every day over the Internet. As the service matures, professional associations publish standards that provide professional guidelines to improve the quality of the services. This article focuses attention on the quality of these e-services in light of professional and ethical standards in the field. It examines the extent to which librarians adhere to professional and ethical guidelines and the role that virtual reference plays in providing services to diverse user groups. First, it discusses adherence to the professional standards and shows that the professional behaviors of librarians vary depending on user, institution, and request types. Then, it discusses the extent to which librarians provide equitable online reference services to diverse users groups and the inconsistent findings from empirical research.
Mechanisms and modifiers of methylmercury-induced neurotoxicity

The neurotoxic consequences of methylmercury (MeHg) exposure have long been known, however a complete understanding of the mechanisms underlying this toxicity is elusive. Recent epidemiological and experimental studies have provided many mechanistic insights, particularly into the contribution of genetic and environmental factors that interact with MeHg to modify toxicity. This review will outline cellular processes directly and indirectly affected by MeHg, including oxidative stress, cellular signaling and gene expression, and discuss genetic, environmental and nutritional factors capable of modifying MeHg toxicity.
Dielectric charging processes and arcing rates of high voltage solararrays

When high-voltage solar arrays are used in the low Earth orbit environment, serious interactions are known to occur between the solar cell material and the surrounding plasma. Arcing is known to be one of the most severe interactions. The charging processes of the dielectric coverglass by charged particles are studied numerically. If there is a field emission site with a high electric field enhancement factor /? on the interconnector, charging processes due to enhanced field electron emission (EFEE) can be initiated and lead to the collisional ionization in neutral gas desorbed from the coverglass. Based on this arcing onset model, an arcing rate is calculated for a high-voltage solar array and good agreement is found with experimental data.
Continuous assays of L-asparaginase by coupling with glutamic dehydrogenase and by cationic glass electrode.

Abstract Continuous assays of l -asparaginase by coupling with the glutamic dehydrogenase reaction and by cationic glass electrode are described. The procedures are about equally sensitive although the latter is simpler and a more direct assay. The two methods gave identical specific activity values for a purified preparation of Escherichia coli l -asparaginase.
Comparison of continuous and batch processes for pectin extraction from sunflower heads

Abstract Sunflower heads are a promising commercial source of low-methoxyl pectin. Although previously reported research was based on a batch extraction process, examples of continuous, countercurrent processes are found with other commodities (beet sugar, vegetable oil). The two types of processes were compared using ground, washed, and dried sunflower heads with 0.75% sodium hexametaphosphate (SHMP) extractant. Under the conditions of pH 2–3.5 at liquid-to-solid (L/S) ratio 32, and L/S ratio 30–45 at pH 3.23, the maximum pectin recovery was similar for the two processes. However, the continuous process maintained maximal recovery over a wide range of pH and L/S ratio. Pectin productivity, which is the rate of pectin extraction per working volume, was much higher in the continuous process than the batch process. At pH 2.5 and L/S ratio 32, it was more than 100% higher. Consequently, the continuous process achieved adequate pectin recovery with less solvent and can be conducted with smaller-size equipment than the batch.
Effects of heavy water on atropa belladonna

The growth of belladonna is strongly inhibited by D 2 O concentrations greater than 50 per cent. The alkaloid content decreases progressively as the deuterium level in the plant increases. Germinative ability of seeds containing up to 40 per cent deuterium is unimpaired.
From Catastrophizing to Recovery: a pilot study of a single-session treatment for pain catastrophizing.

Background Pain catastrophizing (PC) – a pattern of negative cognitive-emotional responses to real or anticipated pain – maintains chronic pain and undermines medical treatments. Standard PC treatment involves multiple sessions of cognitive behavioral therapy. To provide efficient treatment, we developed a single-session, 2-hour class that solely treats PC entitled “From Catastrophizing to Recovery” [FCR].
Elevated-temperature excess heat production in a Pd + D system

Abstract We report a new approach using a Pd|eutectic LiCl + KCl molten salt saturated with excess LiD|Al electrochemical cell to generate excess heat at elevated temperatures. For future utility applications, high-grade heat and high efficiencies can be expected from this novel process when it is operating above 350°C with its faster kinetics, compared with recent room-temperature aqueous-system operations. The electrolyte provides a very reducing environment, which offers the possibility of using less expensive non-noble-metal materials. A modified isoperibol calorimeter was used for the excess heat measurements. Preliminary results show high levels of excess heat output, although the effect remains sporadic. The Pd electrode shows a significant surface microstructural transformation after electrolysis. A small number of α-particles were found in the deuterated Pd electrode.
A new method for analyzing change in dental arch form.

Our method was developed and subsequently computerized in a system incorporating graphicsand quantitative indexes to analyze change in dental arch form as a result of orthodontic treatment and subsequent relapse. The cubic spline function was used to model the form of the dental arches. On the basis of digitized data, splines were fitted to the dental arches before treatment, immediately after treatment, and at least 2 years after removal of retention. The fit of each spline was evaluated through the use of a set of normals to the curve and their average length. The change in form between the registrations was computed, and superimposed graphics of the three records were produced to visually indicate the magnitude of the changes in addition to numeric indexes that reflected the changes. Interjudge and intrajudge reliability were examined and found to be within acceptable limits.
Pathophysiology of pain.

Objective To review the pain pathways in the central and peripheral nervous system and the actions of drugs used to treat pain. Design An overview of pain pathways is presented, beginning in the periphery and progressing centrally, and the ascending and descending pathways are described in detail. Results The nociceptive pathway, consisting of the classic three-neuron chain, is now understood to be a dual system at each level, and the sensation of pain is thought to arrive in the central nervous system with the discriminative component of pain ("first pain") carried separately from the affective-motivational component of pain ("second pain"). In addition to spinal control mechanisms of nociceptive transmission, descending pathways that originate in three major areas—the cortex, thalamus, and brain stem—can modify functions at the spinal level. At every level of the nervous system, a close relationship prevails between somatic pain pathways and visceral pathways. This relationship likely accounts for the transmission of visceral pain and also for autonomic responses to somatic pain and somatic responses to visceral pain. Conclusion By understanding the pathways of pain and the transmitters involved, prevention and treatment of pain will be improved.
An integrated backflashover model for insulation coordination of overhead transmission lines

The lightning performance of overhead transmission lines is measured with the probability of backflashover. This probability is affected by (a) tower type, (b) grounding arrangement, (c) soil resistivity and (d) lightning activity and lightning parameters of the area. This paper presents an integrated model of the transmission towers, tower grounding and overhead line conductors. The model is utilized in a Monte Carlo simulation for the purpose of predicting the lightning performance of a transmission line. This paper presents the models and the simulation method. Typical results for typical transmission towers and grounding arrangements are provided. The model reveals that the grounding arrangement as well as the surge impedance of the transmission tower are important parameters affecting line performance.
Organometallic molecule-inorganic surface coordination and catalytic chemistry. Facile and selective alkane activation by supported tetraallylthorium

The adsorption of Th([eta][sup 3]-allyl)[sub 4] on dehydroxylated alumina yields an active catalyst for the exchange of alkane and cycloalkane C-H bonds with D[sub 2]. C-H reactivities fall in the order primary > secondary > tertiary and less sterically hindered > more sterically hindered. 24 refs., 1 tab.
Residue specific resolution of protein folding dynamics using isotope-edited infrared temperature jump spectroscopy.

A major difficulty in experimental studies of protein folding is the lack of nonperturbing, residue specific probes of folding. Here, we demonstrate the ability to resolve protein folding dynamics at the level of a single residue using 13C18O isotope-edited infrared spectroscopy. A single 13C18O isotopic label was incorporated into the backbone of the 36 residue, three-helix bundle villin headpiece subdomain (HP36). The label was placed in a solvent protected region of the second α-helix of the protein. The 13C18O isotopic label shifted the carbonyl stretching frequency to 1572.1 cm-1 in the folded state, well removed from the 12C16O band of the unlabeled protein backbone. The unique IR signature of the 13C18O label was exploited to probe the equilibrium thermal unfolding transition using temperature-dependent FTIR spectroscopy. The folding/unfolding dynamics were monitored using temperature-jump (T-jump) IR spectroscopy. The equilibrium unfolding studies showed conformational changes suggestive of a loss...
EOSINOPHILIC ROD-LIKE STRUCTURES IN MYELINATED FIBERS OF HAMSTER SPINAL ROOTS

Eosinophilic rod-like structures in myelinated fibers of hamster spinal roots The spinal roots of homozygous mutant hamsters carrying the recessive gene for hind leg paralysis as well as normal controls were studied at both the light and electron microscopic levels. Eosinophilic rod-like inclusions essentially identical to those seen in human brains were observed in the inner loops of Schwann cells of myelinated fibers of the spinal roots. The electron microscope revealed inclusions with the characteristic ‘lattice-like’ structure as well as other purely filamentous bodies. Both mutant and normal hamsters displayed these changes but they were more frequent in mutant animals.
Spectrum of Dizziness Visits to US Emergency Departments: Cross-Sectional Analysis From a Nationally Representative Sample

OBJECTIVE To describe the spectrum of visits to US emergency departments (EDs) for acute dizziness and determine whether ED patients with dizziness are diagnosed as having a range of benign and dangerous medical disorders, rather than predominantly vestibular ones. PATIENTS AND METHODS A cross-sectional study of ED visits from the National Hospital Ambulatory Medical Care Survey (NHAMCS) used a weighted sample of US ED visits (1993-2005) to measure patient and hospital demographics, ED diagnoses, and resource use in cases vs controls without dizziness. Dizziness in patients 16 years or older was defined as an NHAMCS reason-for-visit code of dizziness/vertigo (1225.0) or a final International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis of dizziness/vertigo (780.4) or of a vestibular disorder (386.x). RESULTS A total of 9472 dizziness cases (3.3% of visits) were sampled over 13 years (weighted 33.6 million). Top diagnostic groups were otologic/vestibular (32.9%), cardiovascular (21.1%), respiratory (11.5%), neurologic (11.2%, including 4% cerebrovascular), metabolic (11.0%), injury/poisoning (10.6%), psychiatric (7.2%), digestive (7.0%), genitourinary (5.1%), and infectious (2.9%). Nearly half of the cases (49.2%) were given a medical diagnosis, and 22.1% were given only a symptom diagnosis. Predefined dangerous disorders were diagnosed in 15%, especially among those older than 50 years (20.9% vs 9.3%; P P CONCLUSION Dizziness is not attributed to a vestibular disorder in most ED cases and often is associated with cardiovascular or other medical causes, including dangerous ones. Resource use is substantial, yet many patients remain undiagnosed.
Increased myocardial lactate oxidation in lambs with an aortopulmonary left-to-right shunt.

INCREASED MYOCARDIAL LACTATE OXIDATION IN LAMBS WITH AN AORTOPULMONARY LEFT-TO-RIGHT SHUNT. † 118