cssi/SciSciGPT-SciSciNet huggingface dataset:
Absolute Elastic and Inelastic Differential Cross Sections for the Scattering of Low-Energy Electrons by Potassium

A new method for obtaining absolute differential excitation cross sections in low-energy electron-atom scattering is employed. The method utilizes certain of the kinematic properties of a recoiling-atom beam in an electron-atom crossed-beam configuration to distinguish between elastic scattering events and excitation to various atomic levels. Differential cross sections for elastic scattering and excitation of the $4p$ state of potassium are presented at 1.0, 3.0, 4.4, and 5.2 eV. A combined cross section for the $4s\ensuremath{-}5s$, $3d$ excitation integrated over a restricted angular range is also presented.
Allylic polymers. Diallyl 2‐substituted succinate prepolymers and their properties

Diallyl 2-substituted succinates, obtainable via the addition of alkenes or alkylaromatics to maleic anhydride, undergo intramolecular cyclization during polymerization to low molecular weight prepolymers. The amount of this cyclization and the properties of the cured prepolymers are profoundly affected by the structure of these 2-substituents. Thus, the degree of cyclization decreases with these substituents in the order: aralkyl and isobutyl > unhindered alkenyl > alkyl > hindered alkenyl. Properties of thermosetting molding compounds based on these prepolymers are inferior to those of poly-(diallyl phthalate) molding compounds.
Clutching to "Christian" America: Aimee Semple McPherson, the Great Depression, and the Origins of Pentecostal Political Activism

In 1934 pentecostal evangelist Aimee Semple McPherson went on a national preaching tour to promote her political sermon “America Awake!” Praising “those staunch souls” who were “lifting up hand and voice” to turn the nation “back to the Faith of Our Fathers,” she challenged what she perceived as the nation's secularizing trends. More than two million people—one in every fifty Americans—attended her meetings in addition to even larger audiences that listened in by radio. While she was traveling through Washington, D.C., her publicist, Guido Orlando, introduced the charismatic preacher to Louisiana Senator Huey Long. According to Orlando, “The Kingfish and the Angel clicked so well that, before I could get Aimee out of there, they had decided to run for President and Vice President on the same independent ticket.” Long's assassination the following year foiled the potential plan, leaving no way to confirm Orlando's account. What can be confirmed from abundant new sources is that McPherson was far more politically active and her influence far greater than historians have realized.
APPLICATION OF INFILTRATION THEORY FOR THE DETERMINATION OF EXCESS RAINFALL HYETOGRAPH

ABSTRACT: The purpose of this paper is to show through the use of numerical examples that modern infiltration theory can be used in everyday hydrologic practice. The actual use of four methods of calculation of infiltration rates and of excess rainfall rates is demonstrated for the case when simultaneous data of rainfall and stream flow are available for a watershed. The four methods are: (1) the well known Π-index method, (2) the traditional Horton's infiltration capacity formula, (3) the less traditional Green and Ampt infiltration capacity formula, and (4) a ponding time approach. It is recommended that hydrologists become at least familiar with the numerical procedures involved in the ponding time and postponding infiltration approach. This approach, though not flawless, should be preferred to the other three methods if use of the other three is at all considered.
Power law scaling of the top Lyapunov exponent of a Product of Random Matrices

A sequence of i.i.d. matrix-valued random variables\(\left\{ {X_n } \right\} \cdot X_n = \left( {\begin{array}{*{20}c} 1 & d \\ 0 & 1 \\ \end{array} } \right)\) with probabilityp and\(X_n = \left( {\begin{array}{*{20}c} {1 + a(\varepsilon )} & {b(\varepsilon )} \\ {c(\varepsilon )} & {1 + a(\varepsilon )} \\ \end{array} } \right)\) with probability 1−p is considered. Leta(e) = a0e + O(e), c(e) = c0e + O(e) lime→0b(e) = Oa0,c0, e>0, andb(e)>0 for all e>0. It is shown show that the top Lyapunov exponent of the matrix productXnXn-1...X1, λ = limn → ∞ (1/n) ∣n ∥XnXn-1...X1∥ satisfies a power law with an exponent 1/2. That is, lime → 0(ln λ/ln e) = 1/2.
It Could Be Worse: Selective Evaluation as a Response to Victimization

A theory of victims' responses to their victimization, termed Selective Evaluation, is proposed. It is maintained that the perception that one is a victim and the belief that others perceive one as a victim are aversive. Victims react to this aversive state by selectively evaluating themselves and their situation in ways that are self-enhancing. Five mechanisms of selective evaluation that minimize victimization are proposed and discussed: making social comparisons with less fortunate others (i.e., downward comparison); selectively focusing on attributes that make one appear advantaged; creating hypothetical, worse worlds; construing benefit from the victimizing event; and manufacturing normative standards of adjustment that make one's own adjustment appear exceptional. The theory is integrated with the existing literature on victimization, and possible functions of selective evaluation are discussed.
A scalable consistent second-order SPH solver for unsteady low Reynolds number flows

Abstract Smoothed Particle Hydrodynamics (SPH) has successfully been used to study a variety of cases involving nearly inviscid flows where conservation properties allow for good physical approximation despite poor theoretical approximation properties of differential operators. When used to study unsteady low Reynolds number flow with large dissipation, conservation alone cannot ensure quality of approximation and the traditional approach is inconsistent. An alternative formulation has recently become popular making use of an approximate splitting scheme to ensure a divergence-free velocity field. However, this scheme relies on an inconsistent discretization of the Laplacian that diverges as particles become disordered under flow. We present an incremental pressure correction scheme and combination of existing differential operator renormalizations that are able to achieve second order accuracy in time and space. A brief review of SPH approximation theory is provided to highlight the necessity of these renormalizations in implementing an approximate factorization scheme. We demonstrate that when fast algebraic multigrid preconditioners are used to solve the resulting linear systems, the scheme results in a consistent approximation that is scalable and amenable to parallelization. Several validation cases are presented for which a speedup of several orders of magnitude is achieved over traditional SPH approaches. Finally, an interface has been developed between the particle library LAMMPS and the sparse linear algebra libraries in Trilinos providing a massively parallel 3D SPH capability. Scaling results for up to 134 million particles on 32,768 cores are presented along with a demonstration of the capability to simulate complex 3D geometries. These results show that the added complexity of applying the necessary consistency corrections actually provides a factor of four speed-up per linear solver iteration versus the uncorrected case, despite the additional cost of constructing the corrections. The resulting library provides a method that is consistent, efficient, and second order in both space and time while maintaining the flexibility of classical SPH for single phase flows.
ECOSPIRITUALITY IN PUBLIC FOREIGN LANGUAGE EDUCATION: A CRITICAL DISCOURSE ANALYSIS OF A TRANSFORMATIVE WORLD LANGUAGE LEARNING APPROACH

This critical instrumental case study examines a transformative world language learning approach to a unit on culture in an introductory Japanese class in a public high school. Couched in recent post-9/11 language “policy” debates, which strikingly lack mention of religion, spirituality, or environmental issues of climate change and sustainability, this study examines how a transformative world language learning approach develops and identifies students' environmentally based spirituality and how students articulate such “ecospirituality” in their emerging, standards-based Japanese writing. Critical analysis of written, interview, and classroom data reveals that a transformative world language learning approach may be effective in bridging traditional written literacies with “ecospiritual literacies” in the world language classroom. It also provides a lens for students' socio-dialogic learning of environment-related vocabulary and their subsequent use of it in their Japanese writing. Finally, this study s...
The 2004 Benjamin Franklin Medal in Computer and Cognitive Science presented to Richard M. Karp

The Benjamin Franklin Medal in Computer and Cognitive Science is awarded to Dr. Richard M. Karp for his contributions to the understanding of computational complexity. His work helps programmers find workable solution procedures avoiding approaches that would fail to find a solution in a reasonable amount of time. Scientific, commercial, or industrial situations where his work applies include establishing least-cost schedules for industrial production, transportation routing, circuit layout, communication network design, and predicting the spatial structure of a protein from its amino acid sequencing.
Sequence of ontogenetic development and atrophy of the oral apparatus of six anuran tadpoles.

The development of the oral structures of six species of anuran tadpoles with four different types of mouth parts and the metamorphic atrophy of these structures in two species with different mouth parts are described. The oral labia of typical tadpoles, oral flaps of microhylids, and lateral oral folds of Rhinophrynus are assumed to be homologous. We also suggest that the barbels of the tadpoles of Rhinophrynus are homologs of the marginal papillae of species with an oral disc. Developmental patterns and sequences of the oral structures of all tadpoles examined follow a common pattern: stomodeal invagination, oral pad development, jaw sheeth delimitation, tooth row ridge development, jaw sheath keratinization, and labial tooth keratinization. Developmental patterns remain constant, while interspecific differences are apparent because of truncations of ontogeny at specific stages. Metamorphic atrophy of oral structures occurs roughly in the reverse order of development, although the procedure is rapid and more haphazard than development.
Properties of a van Hove superconductor

Abstract Near a two-dimensional van Hove singularity (vHs), the electronic density-of-states (dos) has a logarithmic singularity which profoundly modifies the electronic properties, and can lead to high z . sbnd ; T c superconductivity. Whereas the normal state properties in the presence of a vHs are very complicated, the superconducting properties can be described very simply. Detailed calculations have been carried out for the superconducting gap and critical temperature of a van-Hove superconductor, incorporating interlayer coupling, strong coupling, and depairing effects due to real phonon scattering and spin scattering. Satisfactory agreement is found with experimental data on the isotope effect, spin-lattice relaxation time, and magnetic penetration depth.
THE CELL TRANSMISSION MODEL, PART II: NETWORK TRAFFIC

Abstract This article shows how the evolution of multi-commodity traffic flows over complex networks can be predicted over time, based on a simple macroscopic computer representation of traffic flow that is consistent with the kinematic wave theory under all traffic conditions. The method does not use ad hoc procedures to treat special situations. After a brief review of the basic model for one link, the article describes how three-legged junctions can be modeled. It then introduces a numerical procedure for networks, assuming that a time-varying origin-destination (O-D) table is given and that the proportion of turns at every junction is known. These assumptions are reasonable for numerical analysis of disaster evacuation plans. The results are then extended to the case where, instead of the turning proportions, the best routes to each destination from every junction are known at all times. For technical reasons explained in the text, the procedure is more complicated in this case, requiring more computer memory and more time for execution. The effort is estimated to be about an order of magnitude greater than for the static traffic assignment problem on a network of the same size. The procedure is ideally suited for parallel computing. It is hoped that the results in the article will lead to more realistic models of freeway flow, disaster evacuations and dynamic traffic assignment for the evening commute.
Synergistic stimulation of pregnenolone synthesis in rat adrenal mitochondria by n-hexane and cardiolipin.

Abstract n -Hexane and cardiolipin each stimulate pregnenolone production by isolated rat adrenal mitochondria. Following corticotropin (ACTH) stimulation, mitochondrial cholesterol metabolism exhibits a fast phase lasting 2 min, followed by a 10-fold slower metabolism. ACTH suppression by dexamethazone or cycloheximide (CX) treatment removes this fast phase. n -Hexane, at concentrations approaching 80% of the aqueous solubility limit (~0.08 m m ), selectively stimulates the slow phase of metabolism, while cardiolipin (100 μ m ) stimulates only the fast phase. Other alkanes and ethers are effective. The effect of n -hexane is dependent on mitochondrial integrity, as evidenced by decreased effects in hypoosmotically shocked mitochondria (outer membrane disrupted) and ineffectiveness in sonicated mitochondria (both membranes disrupted). n -Hexane apparently enhances the transfer of outer membrane cholesterol to inner membrane P -450 scc . Stimulation by cardiolipin is retained by disrupted mitochondria and may involve enhanced availability of P -450 scc to inner membrane cholesterol. When added together, these agents produce more than additive effects on cholesterol metabolism. Preincubation with n -hexane did not increase reactive cholesterol, suggesting that enhanced cholesterol transport occurs only in concert with metabolism of inner membrane cholesterol. Uptake of alkanes into mitochondrial membranes may effect structural changes that facilitate outer to inner membrane cholesterol transfer, but major changes are excluded by the effectiveness of isocitrate as a reductant for P -450 scc . In combination, n -hexane and cardiolipin reproduce the effect of the ACTH-sensitive sterol regulatory peptide on mitochondria [ R. C. Pedersen and A. C. Brownie (1983) Proc. Natl. Acad. Sci. USA 80 , 1882–1886 ], suggesting that peptide action on adrenal mitochondria may resolve into two analogous components.
Does the use of prophylactic antibiotics decrease implant failure

The use of prophylactic antibiotics in implant dentistry is controversial. Given the known risks of antibiotic treatment and lack of consensus on using antibiotics at the time of implant insertion, the purpose of this article was to review available studies on use of perioperative prophylactic antibiotics at the time of implant placement and to provide evidence-based recommendations for antibiotic use. The reviewed studies suggest that a single preoperative dose of 2 g amoxicillin 1 hour before implant placement or 1 g amoxicillin 1 hour preoperatively and 500 mg 4 times daily 2 days postoperatively can reduce the rate of implant failure.
Relations between stimulation of mesolimbic dopamine and place conditioning in rats produced by cocaine or drugs that are tolerant to dopamine transporter conformational change.

Dopamine transporter (DAT) conformation plays a role in the effectiveness of cocaine-like and other DAT inhibitors. Cocaine-like stimulants are intolerant to DAT conformation changes having decreased potency in cells transfected with DAT constructs that face the cytosol compared to wild-type DAT. In contrast, analogs of benztropine (BZT) are among compounds that are less affected by DAT conformational change. We compared the displacement of radioligand binding to various mammalian CNS sites, acute stimulation of accumbens shell dopamine levels, and place conditioning in rats among cocaine and four BZT analogs with Cl substitutions on the diphenyl-ether system including two with carboalkoxy substitutions at the 2-position of the tropane ring. Binding assays confirmed high-affinity and selectivity for the DAT with the BZT analogs which also produced significant stimulation of mesolimbic dopamine efflux. Because BZT analogs produced temporal patterns of extracellular dopamine levels different from those by cocaine (3–10 mg/kg, i.p.), the place conditioning produced by BZT analogs and cocaine was compared at doses and times at which both the increase in dopamine levels and rates of increase were similar to those produced by an effective dose of cocaine. Despite this equilibration, none of the BZT analogs tested produced significant place conditioning. The present results extend previous findings suggesting that cocaine-like actions are dependent on a binding equilibrium that favors the outward conformational state of the DAT. In contrast, BZT analogs with reduced dependence on DAT conformation have reduced cocaine-like behavioral effects and may prove useful in development of medications for stimulant abuse.
Visualizing the Structural Evolution of LSM/xYSZ Composite Cathodes for SOFC by in-situ Neutron Diffraction

Thermal stability of composite cathodes for solid oxide fuel cells, the mixtures of (La0.8Sr0.2)0.95MnO3−δ (LSM) and (Y2O3)x(ZrO2)1−x (xYSZ, x = 3, 6, 8 and 10), is determined using in-situ neutron diffraction. Thanks to the most advanced high flux neutron source, our work highlights the visualization of the phase evolutions in heterogeneous material systems at high temperatures, along with the analysis of the diffusion activities of transition metal ions that reveal the reaction mechanism and kinetics. It is found that the tetragonal-to-cubic phase transition in YSZ at T > 900°C leads to a heterogeneous redistribution of Mn ions. The subsequent reaction of LSM and YSZ occurring at T > 1100°C is revealed as a three-stage kinetic process, yielding La2Zr2O7, SrZrO3 and MnO. The diffusion activities of Y, Mn and La ions in the heterogeneous systems at elevated temperatures are derived by the structural analysis, and the three-stage reaction of YSZ and LSM is found strongly correlated to ions' behaviors as functions of temperature.
π–π* Emission from a tetrazine derivative complexed with zinc ion in aqueous solution: a unique water-soluble fluorophore

A 3,6-bis(5-amino-2-pyridyl)-1,2,4,5-tetrazine exhibits strong π-π* fluoresce in the presence of zinc ion (Zn(2+)) in aqueous solution, whereas it is not fluorescent in the absence of Zn(2+) as well as in the presence of competing metal ions.
Accelerated life test planning with independent lognormal competing risks

In accelerated life testing (ALT), products are exposed to stress levels higher than those at normal use in order to obtain information in a timely manner. Past work on planning ALT is predominantly on a single cause of failure. This article presents methods for planning ALT in the presence of k competing risks. Expressions for computing the Fisher information matrix are presented when risks are independently distributed lognormal. Optimal test plans are obtained under criteria that are based on determinants and maximum likelihood estimation. The proposed method is demonstrated on ALT of motor insulation.
Online lecture delivery paired with in class problem-based learning … Does it enhance student learning?

Abstract Objective To assess the impact of a novel teaching model on student learning and perception. Method A hybrid teaching model was implemented within the second professional year of the Doctor of Pharmacy curriculum at Northeastern University in Boston, Massachusetts. This Institutional Review Board–approved study enrolled 97 students who accessed online materials in place of traditional lectures over a total of six lectures and had that information re-enforced via in-class active learning. All student quiz scores were compared using a paired t-test. A postsurvey was sent to all students to capture their attitudes and use of this teaching model. Results Students performed statistically significantly higher on quizzes and examinations when using this hybrid teaching model. Student attitudes toward this teaching model were mixed, largely because of perceived increases in their (or student) workload. Conclusion This study demonstrated that using technology, such as podcasts and electronic lecture delivery enhances learning and bridges gaps with this more technologically advanced generation of students.
An arithmetic operator and the functions on which it is part-bounded

Approximate eigenfunctions of certain self-adjoint arithmetic operators are characterized, even when the eigenfunctions are only partially known.
Two-sided E-rings

Abstract Let R be a ring, 1∈R, and R+ the additive group of R. We define Mult(R) to be the subring of End(R+) generated by all left and right multiplications by elements of R. The ring R is called a two-sided E-ring if End(R+)=Mult(R). If R is torsion-free of finite rank (tffr), we call R a quasi-two-sided E-ring if Q End(R + )= Q Mult(R) . We investigate (quasi)-two-sided E-rings, give several examples and construct large two-sided E-rings R with prescribed center S such that End(R+)=Mult(R)≈R⊗SRop≈R. Thus our rings R are examples of two-sided E-rings that are weak E-rings as well, i.e. R≈ End(R+), but R is not an E-ring.
Gram Negative Sinusitis: An Emerging Clinical Entity?:

Traditionally sinusitis has been classified as acute or chronic based on the duration of patient symptoms, and treatment has been based on empiric principles, as the bacteriologic spectrum is felt ...
Calcium Carbonate from Non-Coralline Algae: ABSTRACT

In addition to the red or crustose coralline algae, some other simple marine algae secrete carbonate in tropical seas. Secretion of aragonite by Halimeda discoidea Decaisne, a calcareous green alga, and Padina japonica Yamada, a calcareous brown alga, was investigated in shallow Hawaiian waters. Along traverses between reef and shore, Padina is most abundant close to shore, whereas Halimeda flourishes in the deepest water, generally midway between shore and reef front. In Padina, the proportion of calcium carbonate to total body weight is inversely proportional to abundance of the algae on the sea floor, whereas for Halimeda the proportion is directly related to relative abundance. For Halimeda as much as 70 per cent of the body weight may be aragonite. Production of calcium carbonate and of total organic material has been compared for shallow water specimens, for specimens dredged from deeper water, and for calcareous and noncalcareous algae described by Doty recently. Aragonite secreted by algae contributes an important volume of material for subsequent diagenesis in tropical carbonate sediments that are ultimately converted to limestones. End_of_Article - Last_Page 273------------
Tyrosine-Selective Protein Alkylation Using π-Allylpalladium Complexes

A new protein modification reaction has been developed based on a palladium-catalyzed allylic alkylation of tyrosine residues. This technique employs electrophilic pi-allyl intermediates derived from allylic acetate and carbamate precursors and can be used to modify proteins in aqueous solution at room temperature. To facilitate the detection of modified proteins using SDS-PAGE analysis, a fluorescent allyl acetate was synthesized and coupled to chymotrypsinogen A and bacteriophage MS2. The tyrosine selectivity of the reaction was confirmed through trypsin digest analysis. The utility of the reaction was demonstrated by using taurine-derived carbamates as water solubilizing groups that are cleaved upon protein functionalization. This solubility switching technique was used to install hydrophobic farnesyl and C(17) chains on chymotrypsinogen A in water using little or no cosolvent. Following this, the C(17) alkylated proteins were found to associate with lipid vesicles. In addition to providing a new protein modification strategy targeting an under-utilized amino acid side chain, this method provides convenient access to synthetic lipoproteins.
Direct observation of oriented molecular adsorption at step edges: a cryogenic scanning tunneling microscopy study

Abstract A cryogenic scanning tunneling microscope has been used to investigate the adsorption of thiophene, 2,5-dimethylthiophene, and 2,2′-bithiophene on the Ag(111) surface at 120 K. STM images reveal that all three molecules preferentially bond at step edges. Images of 2,2′-bithiophene and 2,5-dimethylthiophene at the step edge show them to be elongated, while thiophene molecules appear nearly circular. The observed elongation for 2,2′-bithiophene and 2,5-dimethylthiophene is attributed to geometric contrast reflecting the intrinsic shape of these molecules. All molecules of a given chemical identity appear to be oriented in the same direction with respect to the step edge, demonstrating that the interactions between the molecules and the step edge are sufficiently strong and sufficiently local to hold the molecules in specific rotational configurations at the step edge.
Phosphorylation and coupling of ζ-chains to activated T-cell receptor (TCR)/CD3 complexes from peripheral blood T-cells of elderly humans

Abstract Aging is often accompanied by altered T-cell signaling and functions. Signals mediated through the T-cell receptor (TCR)/CD3 complex are associated with tyrosine phosphorylations of ζ-chains by the regulated activities of protein tyrosine kinases p56lck and p59fyn as well as protein tyrosine phosphatases. In the present investigation, the coupling and phosphorylation of ζ-chains to TCR/CD3 immunocomplexes were examined in peripheral blood T-cells from 13 elderly and young humans stimulated by ligation of the TCR/CD3 with cross-linked anti-CD3ϵ monoclonal antibody OKT3. Western blots analyzing the non-covalent coupling of ζ-chains to TCR/CD3 immunocomplexes from Brij-96 detergent lysates of anti-CD3 ligated T-cells showed that the levels of ζ-chains within TCR/CD3 immunocomplexes from T-cells of elderly and young subjects did not significantly differ. By contrast, the levels of phosphorylated ζ-chains generated during in vitro phosphorylations of TCR/CD3 immunocomplexes from elderly subjects were significantly reduced and averaged 44% of those observed for anti-CD3ϵ ligated T-cells from young subjects. Analyses of the levels of ζ-chain coupling and phosphorylations in T-cells from each of the 13 elderly individuals also showed that the reductions in ζ-chain phosphorylations were heterogeneous and unrelated to modest reductions in coupling. Furthermore, the age-related decreases in ζ-chain phosphorylations were not due to diminished frequencies of CD3ϵ+ cells or densities of CD3ϵ surface receptors and could be observed without reductions in ϵ-chain phosphorylations. These results suggest that aberrancies of ζ-chain phosphorylations can occur in T-cells of elderly humans independent from any uncoupling of ζ-chains to activated TCR/CD3 complexes.
Blood alcohol concentration and severity of microencephaly in neonatal rats depend on the pattern of alcohol administration.

Abstract A rat model of third trimester fetal alcohol exposure was used to examine how the pattern of administration of a daily alcohol dose influences the pattern of blood alcohol concentrations (BACs) and the severity of brain growth restriction. Four groups of rats were artificially reared from postnatal days 4 to 10. Three of the groups received an equivalent daily dose of alcohol (6.6 g/kg/day) but in different daily patterns. To one group, the dose was administered continuously in a 2.5% (v/v) solution; in two other groups, the dose was condensed into either 7.5% or 15.0% (v/v) solutions. A fourth group (gastrostomy controls) received a formula containing maltose-dextrin, which was isocaloric to the 2.5% alcohol solution. BACs were determined twice daily at times designed to estimate the daily peak and minimum BACs. The rats were killed on postnatal day 10 and total brain weights, cerebellar weights and brainstem weights were measured. In each of the three groups given alcohol, the maximum BAC occurred on the afternoon of postnatal day 6. Thereafter, daily peak BAC declined progressively. The more concentrated the pattern of alcohol administration, the higher was the maximum BAC achieved and the more severe was the interference with brain growth. While the group receiving the alcohol dose in small continuous fractions (2.5%) did not exhibit any significant microencephaly, relative to gastrostomy controls, the groups receiving the dose in more concentrated forms (7.5% and 15.0%) exhibited significant brain growth restriction (reduced 19% and 31%, respectively, relative to controls). Therefore, the peak BAC and the severity of the alcohol-induced brain growth restriction for a given daily dose of alcohol depend on the pattern of alcohol administration.
An evolving multi-agent scenario generation framework for simulations in preventive medicine education

We describe the design, implementation and evaluation of a novel multi-agent scenario generation framework for interactive virtual reality simulations towards preventive medicine education. Our scenario generation framework is based on recordings of human movements from a distributed sensor networks deployed in a real-world physical setting. The components of our framework include the generation of unique virtual agent behaviors from the sensor data, and algorithms for the generation of low level or gross movement behaviors such as path determination, directional traffic flows, collision avoidance and overtaking. The framework also includes the generation of high level fine actions for multi-agents such as techniques for interactive activities in pedagogical scenarios based on environment and temporal triggers. We applied our multi-agent scenario generation framework in an interactive simulation for hand hygiene education, and conduct an initial usability study to assess the educational benefits of the simulation to nursing students and evaluated the performance characteristics of our framework. Results of our quantitative and qualitative evaluations suggest that our framework was robust in creating engaging, compelling, and realistic interactive training scenarios with multiple virtual agents in simulated hospital situations.
The radial diffusivity and magnetization transfer pool size ratio are sensitive markers for demyelination in a rat model of type III multiple sclerosis (MS) lesions

Determining biophysical sensitivity and specificity of quantitative magnetic resonance imaging is essential to develop effective imaging metrics of neurodegeneration. Among these metrics, apparent pool size ratio (PSR) from quantitative magnetization transfer (qMT) imaging and radial diffusivity (RD) from diffusion tensor imaging (DTI) are both known to relate to histological measure of myelin density and integrity. However their relative sensitivities towards quantitative myelin detection are unknown. In this study, we correlated high-resolution quantitative magnetic resonance imaging measures of subvoxel tissue structures with corresponding quantitative myelin histology in a lipopolysaccharide (LPS) mediated animal model of MS. Specifically, we acquired quantitative magnetization transfer (qMT) and diffusion tensor imaging (DTI) metrics (on the same tissue sample) in an animal model system of type III oligodendrogliopathy which lacked prominent lymphocytic infiltration, a system that had not been previously examined with quantitative MRI. We find that the qMT measured apparent pool size ratio (PSR) showed the strongest correlation with a histological measure of myelin content. DTI measured RD showed the next strongest correlation, and other DTI and relaxation parameters (such as the longitudinal relaxation rate (R1f) or fractional anisotropy (FA)) showed considerably weaker correlations with myelin content.
Further studies of opioids and intake of sweetened alcoholic beverage

Rats were placed on a daily regimen of water deprivation followed by a limited opportunity to take either water or a sweetened alcoholic beverage. Across days of opportunity, they took less water and more alcohol until they were taking considerable amounts of alcohol. Naloxone, the classic antagonist at opioid receptors, was given prior to opportunity to drink and it reduced intakes of alcoholic beverage. Small doses of morphine, the classic agonist, increased intakes of alcoholic beverage at doses as low as 0.41 mg/kg. The effects of two other antagonists at opioid receptors (LY117413 and MR2266) were also tested. Both reduced intakes of alcohol. The data showing that more than one or two opioid antagonists reduce intakes of alcoholic beverages, even palatable beverages usually taken in large amounts, and that morphine increases intakes at very low doses, strengthen the idea that endogenous opioid systems are involved in modulating intake of alcohol.
Effect of natural convection on stability of flow in a vertical pipe

If water is heated or cooled while flowing through a vertical pipe with a laminar motion, the velocity profile will differ from the parabolic shape for isothermal flow due to density variations in the fluid. If a constant heat flux is used at the wall and if the changes in temperature affect only the density appearing in the gravity term of the equations of motion, a condition is attained far downstream in the heat-transfer section such that there is no further change in the velocity profile. The shape of this fully developed velocity profile depends on the ratio of the heat flux to the flow rate. The stability of flow in an electrically heated pipe 762 diameters long was studied by detecting temperature fluctuations in the effluent. By use of a carefully designed entry and a long isothermal section prior to the heat exchange section, inlet disturbances were eliminated and transition to an unsteady flow resulted from a natural instability of the distorted profiles. It was found that the stability depends primarily on the shape of the velocity profile and only secondarily on the value of the Reynolds number, if at all. For upflow heating the flow first becomes unstablemore » when the velocity profiles develop points of inflexion. Transition to an unsteady flow involves the gradual growth of small disturbances and therefore it is quite possible to have unstable flows without observing transition because the pipe is not long enough for the disturbances to attain a measurable amplitude. For downflow heating the flow instability is associated with separation at the wall. Transition to an unsteady flow is sudden and therefore transition occurs shortly after an unstable flow occurs. It is suggested that a change from a steady symmetrical to a steady unsymmetrical flow occurs in downflow when the profile develops points of inflexion.« less
Fuzzy adaptive Voronoi-diagram-based clustering of textured images

Clustering means grouping of similar objects by optimizing a certain criterion. Clustering techniques are very common and useful in image processing and pattern recognition, especially for unsupervised initial segmentation of images. Images always contain some imprecise, uncertain or ambiguous regions and structures. Fuzzy sets constituted a good framework to represent and take into account these imprecisions. Their use leads to image processing methods where binary decision are not taken at intermediate levels, where only partial information is available. As mentioned by Bloch the usage of fuzzy sets in image processing relies on two different approaches - symbolic, where decision rules are derived from fuzzy logic, and numerical, where fuzzy sets directly represent the spatial structure of the image. Our work combines these two approaches.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
The effect of transverse-variation of solar wind speed on cosmic rays

Abstract The effect of the variation of solar wind speed with solar latitude on the cosmic ray intensity observed at the Earth is examined by means of a simplified mathematical model. It appears that semi-annual intensity variations of several per cent should occur for cosmic rays with rigidities below a few GV.
Procedures for improving a relativistic distorted-wave approach for excitation of ions by electron impact.

A simple way to obtain a completely general distorted-wave excitation program in the convenient factorized form of Bar-Shalom, Klapisch, and Oreg [Phys. Rev. A 38, 1773 (1988)] is described. Procedures for improving numerical accuracy are also discussed, and results obtained by these procedures are compared with other work.
Demonstration of simultaneous cation-exchange and reversed-phase mechanisms on a strong-acid cation-exchange column

It is demonstrated in this report that a conventional strong-acid cation-exchange column can exhibit reversed-phase chromatographic behavior simultaneously with ion-exchange. Adjusting the pH to control cation retention has no effect on the retention of neutral organic analytes. Likewise, changes in the methanol content of the mobile phase to adjust organic analyte retention causes only a small decrease in retention of metal ions in the 0 to 10% (v/v) methanol range, and no significant effect beyond that. Linear calibration behavior of both metal cations and neutral organic analytes is found on this column over three-order of magnitude. Examples of simultaneous metal cation-neutral organic separations in both the isocratic and gradient modes are shown, with conductivity detection for the metal ions and UV for the organic analytes. An isocratic separation of metal ions and neutrals in a vitamin pill is also demonstrated.
Targeting the Giant Cell Tumor Stromal Cell: Functional Characterization and a Novel Therapeutic Strategy

Giant cell tumor of bone (GCTB) is a benign, locally destructive neoplasm, with tumors comprised of mesenchymal fibroblast-like stromal cells; monocytic, mononuclear cells of myeloid lineage; and the characteristic osteoclast-like, multinucleated giant cells. Hampering the study of the complex interaction of its constituent cell types is the propensity of longstanding, repeatedly passaged cell cultures to undergo phenotypic alteration and loss of osteoclast-inducing capacities. In this study, we employed a novel, single-step technique to purify freshly harvested stromal cells using a CD14-negative selection column. Using 9 freshly harvested GCTB specimens and the purified stromal cell component, we performed analyses for markers of osteoblast lineage and analyzed the capacity of the stromal cells to undergo osteoblastic differentiation and induce osteoclastogenesis in co-cultures with monocytic cells. Successful purification of the CD14-negative stromal cells was confirmed via flow cytometric analysis and immunocytochemistry. Osteogenic media upregulated the expression of osteocalcin, suggesting an osteoblastic lineage of the GCTB stromal cells. The effects of the Wnt pathway agonist, SB415286, and recombinant human bone morphogenetic protein (BMP)-2 on osteoblastogenesis varied among samples. Notably, osteogenic media and SB415286 reversed the receptor activator of NF-κB ligand (RANKL)/osteoprotegerin (OPG) expression ratio resulting in diminished osteoclastogenic capacity. Recombinant human BMP2 had the opposite effect, resulting in enhanced and sustained support of osteoclastogenesis. Targeting the giant cell tumor stromal cell may be an effective adjunct to existing anti-resorptive strategies.
Cognition and phonology in acquisition of plurals and possessives by Luo children

Abstract At least two kinds of cognitive operations are utilized by children in their acquisition of the productive bound morphemes of their language. One is a set of strategies to generalize the application of the forms to appropriate lexico-grammatical categories. These include rote memory, combination, and analogy. Another set of cognitive operations involves the phonological changes that occur in affixation. A test using nonce forms in morphophonology was administered to Luo-speaking children in Kenya. The results indicate that morphophonological processes in the acquisitions of Luo plurals and possessives present different degrees of difficulty for the children. Difficulty is defined by later acquisition. The easiest change is addition of homorganic stops or affricates to stem-final nasal. The second easiest change is voicing, either a change from voiced to unvoiced or from unvoiced to voiced of stem-final consonant. The most difficult change was phone substitution, i.e. a change in mode and place of articulation. The type of morphophonological alteration in a language is thus likely to affect the rate and order of acquisition.
Coupling protein engineering with probe design to inhibit and image matrix metalloproteinases with controlled specificity.

Matrix metalloproteinases (MMPs) are zinc endopeptidases that play roles in numerous pathophysiological processes and therefore are promising drug targets. However, the large size of this family and a lack of highly selective compounds that can be used for imaging or inhibition of specific MMPs members has limited efforts to better define their biological function. Here we describe a protein engineering strategy coupled with small-molecule probe design to selectively target individual members of the MMP family. Specifically, we introduce a cysteine residue near the active-site of a selected protease that does not alter its overall activity or function but allows direct covalent modification by a small-molecule probe containing a reactive electrophile. This specific engineered interaction between the probe and the target protease provides a means to both image and inhibit the modified protease with absolute specificity. Here we demonstrate the feasibility of the approach for two distinct MMP proteases, MMP...
Computational identification of a phospholipidosis toxicophore using (13)C and (15)N NMR-distance based fingerprints.

Abstract Modified 3D-SDAR fingerprints combining 13 C and 15 N NMR chemical shifts augmented with inter-atomic distances were used to model the potential of chemicals to induce phospholipidosis (PLD). A curated dataset of 328 compounds (some of which were cationic amphiphilic drugs) was used to generate 3D-QSDAR models based on tessellations of the 3D-SDAR space with grids of different density. Composite PLS models averaging the aggregated predictions from 100 fully randomized individual models were generated. On each of the 100 runs, the activities of an external blind test set comprised of 294 proprietary chemicals were predicted and averaged to provide composite estimates of their PLD-inducing potentials (PLD+ if PLD is observed, otherwise PLD−). The best performing 3D-QSDAR model utilized a grid with a density of 8 ppm × 8 ppm in the C–C region, 8 ppm × 20 ppm in the C–N region and 20 ppm × 20 ppm in the N–N region. The classification predictive performance parameters of this model evaluated on the basis of the external test set were as follows: accuracy = 0.70, sensitivity = 0.73 and specificity = 0.66. A projection of the most frequently occurring bins on the standard coordinate space suggested a toxicophore composed of an aromatic ring with a centroid 3.5–7.5 A distant from an amino-group. The presence of a second aromatic ring separated by a 4–5 A spacer from the first ring and at a distance of between 5.5 A and 7 A from the amino-group was also associated with a PLD+ effect. These models provide comparable predictive performance to previously reported models for PLD with the added benefit of being based entirely on non-confidential, publicly available training data and with good predictive performance when tested in a rigorous, external validation exercise.
Problems with using components in educational software

Reuse is vital in the education world because the time and money necessary to create high quality educational software is prohibitive. Estimates for the cost of creating a single well designed, highly graphical and interactive online course in the commercial domain range from several hundred thousand dollars to a million or more. Thus the idea of reusable software components that can be easily shared is tremendously appealing. In fact, "component" has become a buzzword in the educational software community, with millions of dollars from the National Science Foundation and other sponsors funding a wide variety of "component-based" projects. But few, if any, of these projects, have approached the grand vision of creating repositories of easy to reuse components for developers and educators. This paper investigates some of the factors that stand in the way of achieving this goal.We begin by defining the word component and looking at several projects using components, with a focus on our Exploratories project at Brown University. We then discuss challenges in: Searching and Metadata, Quality Assurance, Programming in the University Environment, Platform and System Specificity, Social Issues, Intellectual Property Issues, and Critical Mass. We look at relevant software engineering issues and describe why we believe educational applications have unique factors that should be considered when using components.
Neuron/target matching between chorda tympani neurons and taste buds during postnatal rat development.

During postnatal development, a relationship is established between the size of individual taste buds and number of innervating neurons. To determine whether rearrangement of neurons that innervate taste buds establishes this relationship, we labeled single taste buds at postnatal day 10 (P10) and again at either P15, P20, or P40 with retrograde fluorescent neuronal tracers. The number of single- and double-labeled geniculate ganglion cells was counted, and the respective taste bud volumes were measured for the three groups of rats. The current study replicates findings from an earlier report demonstrating that the larger the taste bud, the more geniculate ganglion cells that innervate it. This relationship between taste bud size and number of innervating neurons is not apparent until P40, when taste bud size reaches maturity. These findings are extended here by demonstrating that the number of neurons that innervate taste buds at P10, when taste bud size is small and relatively homogeneous, predicts the size that the respective taste bud will become at maturity. Moreover, while there is some neural rearrangement of taste bud innervation from P10 to P40, rearrangement does not impact the relationship between taste bud size and innervating neurons. That is, the neurons that maintain contact with taste buds from P10 through P40 accurately predict the mature taste bud size. Therefore, the size of the mature taste bud is determined by P10 and relates to the number of sensory neurons that innervate it at that age and the number of neurons that maintain contact with it throughout the first 40 days of postnatal development. © 2000 John Wiley & Sons, Inc. J Neurobiol 43: 98–106, 2000