cssi/SciSciGPT-SciSciNet huggingface dataset:
Ancillary properties of vapor-deposited carbide coatings

Abstract Instrument-size gas-bearing applications demanding hard wear-resistant coatings on lightweight thermally conductive substrates frequently require that properties such as electrical resistivity, magnetic susceptibility and adhesion integrity be evaluated. Titanium carbide and tungsten carbide coatings, approximately 1 to 2 μm thick, were sputter deposited on beryllium oxide substrates. In addition, titanium carbide coatings approximately 50 μm thick were prepared on beryllium oxide substrates by activated reactive evaporation. Electrical resistivity was measured at various locations on the coating surface with a square four-point probe array. Magnetic susceptibility was measured using the Gouy test method in which a specimen is partially suspended in a magnetic field and the resulting force of attraction is measured. Since adhesion integrity is essential to the success of any coating application, a direct tensile pull test was performed on each specimen. The resulting fracture surface showed coating thickness, and the structure and characterization was accomplished by scanning electron microscopy and X-ray analysis.
Dynamic Intervention: Pathogen Disarmament of Mitochondrial-Based Immune Surveillance

In this issue of Cell Host & Microbe, Suzuki et al. (2014) describe a Vibrio cholerae Type-III-secreted effector that targets mitochondrial dynamics to dampen host innate immune signaling. This suggests that mammalian hosts possess surveillance mechanisms to monitor pathogen-mediated alterations in the integrity of normal cellular processes and organelles.
A Comprehensive Prognostics Approach for Predicting Gas Turbine Engine Bearing Life

Development of practical and verifiable prognostic approaches for gas turbine engine bearings will play a critical role in improving the reliability and availability of legacy and new acquisition aircraft engines. In addition, upgrading current United States Air Force (USAF) engine overhaul metrics based strictly on engine flight hours (EFH) and total accumulated cycles (TAC) with higher fidelity prognostic models will provide an opportunity to prevent failures in engines that operate under unusually harsh conditions, and will help avoid unnecessary maintenance on engines that operate under unusually mild conditions. A comprehensive engine bearing prognostic approach is presented in this paper that utilizes available sensor information on-board the aircraft such as rotor speed, vibration, lube system information and aircraft maneuvers to calculate remaining useful life for the engine bearings. Linking this sensed data with fatigue-based damage accumulation models based on a stochastic version of the Yu-Harris bearing life equations with projected engine operation conditions is implemented to provide the remaining useful life assessment. The combination of health monitoring data and model-based techniques provides a unique and knowledge rich capability that can be utilized throughout the bearing’s entire life, using model-based estimates when no diagnostic indicators are present and using the monitored features such as oil debris and vibration at later stages when failure indications are detectable, thus reducing the uncertainty in model-based predictions. A description and initial implementation of this bearing prognostic approach is illustrated herein, using bearing test stand run-to-failure data and engine test cell data.Copyright © 2004 by ASME
Probe of three-dimensional chiral topological insulators in an optical lattice

An experimental scheme is proposed allowing the properties of topological insulators to be studied using cold fermionic atoms in an optical lattice.
Theoretical study of CO adsorption on Au catalysts under environmental catalytic conditions

Abstract Density Functional Theory calculations with both standard GGA and hybrid functionals are performed on Au adatoms, steps, and low index surfaces with coordination numbers (CNs) varying from 3 to 9. The results are used to study adsorption thermodynamics and reactivity of CO on Au nanoparticles. We find that the hybrid functional improves calculated site preferences and predicts CO top site adsorption, regardless of the Au CN, in good agreement with experiments. The calculated adsorption energies vary monotonically with respect to Au CNs, and the results from the hybrid functional are around 20% smaller than the corresponding values from the GGA–PBE functional. A comparison with experimental adsorption energies suggests that these functionals may bound the true CO–Au interaction strength, and seven-coordinated Au atoms may be the active low-coordinated sites on many Au single crystal surfaces. However, thermodynamic analysis on Wulff-like Au particles at ambient temperatures shows that, even though the number of 6-coordinated corner Au atoms is much less than the number of 7-coordinated edge Au atoms and of higher-coordinated Au atoms, they are the dominant sites for CO adsorption on Au nanoparticles with sizes up to 10 nm. In addition, we find that CO adsorption is not influenced by the shape of Au nanoparticles, but the CO oxidation reaction may be.
Reverse osmosis as a pre-treatment for aqueous phase of mine plant tailings for submarine disposal

Submarine disposal of mine tailings is a relatively recent technology that holds the promise of solving the recurring problems that the mining industry has had with tailings disposal. Implementation of this technology is however contingent upon the pre-treatment of the tailings, particularly those in the aqueous phase. One of the best-known methods to eliminate dissolved metal ions from an aqueous phase is reverse osmosis (RO). In this study, effluent water from mines was passed through a variety of RO membranes and the efficacy of removal was measured. RO was found to be an extremely effective method for cleaning mine effluent, and in the absence of cost limitations, can provide a significant solution to the mine tailings problem.
Delay-aware co-designs for wide-area control of power grids

In this paper we address the problem of wide-area control of power systems in presence of different classes of network delays. We pose the control objective as an LQR minimization of the electro-mechanical states of the swing equations, and present a so-called arbitration approach by which the flexibilities of the communication network such as scheduling policies, bandwidth, etc., can be exploited to co-design a delay-aware state feedback control law. A key feature of our method is that it retain the samples of the control input until a desired time instant using shapers before releasing them for actuation. This essentially means that we regulate the delays entering our controller. Hence, unlike the traditional robust control designs reported in the power system literature, our design is delay-aware, not delay-tolerant. They are, therefore, much more reliable and practical to implement. We illustrate our results using a 50-bus, 14-generator, 4-area power system model, and show how the proposed arbitrated controller can guarantee significantly better closed-loop performance than traditional robust controllers.
Saving Children, Saving Haiti? Child Vulnerability and Narratives of the Nation.

Long before the earthquake in Haiti on 12 January 2010, but particularly since, international media and humanitarian groups have drawn attention to the ‘vulnerable child’ in Haiti, a child often po...
Relative abundance of different cadherins defines differentiation of mesenchymal precursors into osteogenic, myogenic, or adipogenic pathways.

Cadherins, a family of cell-cell adhesion molecules, provide recognition signals that are important for cell sorting and aggregation during tissue development. This study was performed to determine whether distinct cadherin repertoires define tissue-specific lineages during differentiation of immature C3H10T1/2 and C2C12 mesenchymal cells. Both cell lines expressed mRNA for N-cadherin (N-cad), cadherin-11 (C11), and R-cadherin (R-cad). After induction of osteogenesis by recombinant human BMP-2 (rhBMP-2) treatment, steady state N-cad mRNA slightly increased in C3H10T1/2 cells. Likewise, the abundance of C11 mRNA increased in both cell lines, although the changes were more remarkable in C2C12 cells. By contrast, R-cad expression was almost shut off by rhBMP-2. The immature but committed osteoblastic MC3T3-E1 cells exhibited only minor changes in N-cad and C11 mRNA abundance after rhBMP-2 treatment. Whereas adipogenic differentiation was associated with a net decrease of N-cad and C11 expression in C3H10T1/2 cells, induction of myogenesis in C2C12 cells resulted in up-regulation of N-cad, while R-cad mRNA became undetectable in either case. Similarly, the adipocytic 3T3-L1 cells expressed very low levels of all cadherins when fully differentiated. Therefore, the repertoire of cadherins present in undifferentiated mesenchymal cells undergoes distinct changes during transition to mature cell phenotypes. Although neither N-cad nor C11 represent strict tissue-specific markers, the relative abundance of these mesenchymal cadherins defines lineage-specific signatures, perhaps providing recognition signals for aggregation and differentiation of committed precursors.
A developmental profile of tocol accumulation in oat seeds

Oats are a good source of many vitamins and minerals, including compounds that collectively constitute vitamin E, the tocols. Tocols are comprised of two subgroups, tocopherols and tocotrienols. Due to their potent antioxidant properties, attention has been given to the health benefits of tocols in oats. However, little is known about developmental aspects of their accumulation. Moreover, aside from their role in protecting membranes from oxidative damage, their possible physiological roles in planta have largely gone uninvestigated. In this study, we quantified tocol accumulation at five time points during oat seed development, and also compared tocol concentration and composition in the whole seed both to endosperm and embryos at a late stage of seed development. The temporal pattern of accumulation of the tocol subgroups was different. Both tocotrienols and tocopherols steadily increased over the course of seed development; however, tocotrienol progression was sigmoidal and tocopherol linear. By the end of seed development, tocotrienols were the most abundant tocol both in whole seed and in seed with embryos removed. In contrast, embryos contained higher concentrations of tocopherols than tocotrienols late in seed development. Differences in both temporal and spatial distribution during seed development suggest distinct roles for tocotrienols and tocopherols.
Population Density in Suburban Chicago: A Bid-rent Approach

Bid-rent theory suggests that the dependent variable of a population density function is unobserved (or population equals zero) if land values are relatively low in residential use. If the errors o...
Impairment of caffeine clearance by chronic use of low-dose oestrogen-containing oral contraceptives.

The effect of chronic (>3 months) administration of low-dose oestrogen-containing (<50 µg oestrogen) oral contraceptives (OCS) on the pharmacokinetics of caffeine has been examined in a treated females matched with 9 non-smoking, drug-free, healthy control females of similar age, weight and ethnic origin. Each subject received 162 mg caffeine base orally after an overnight fast. OCS subjects had a prolonged elimination half-life of caffeine, (mean 7.88 h vs 5.37 h in the controls). This was the result of marked impairment of the plasma clearance of caffeine (1.05 vs 1.75 ml/min/kg, respectively) with no change in apparent volume of distribution (0.685 in OCS vs 0.750 l/kg in the control group). The absorption parameters determined were peak plasma caffeine concentration (3.99 vs 4.09 µg/ml) and time to peak concentration after drug administration (1.52 vs 0.79), which was moderately prolonged in OCS users. Thus, caffeine clearance, previously reported to be a specific marker of cytochrome P-448 activity in man, is decreased by chronic OCS use. This suggests that OCS may cause significant impairment of this enzyme activity as assessed in vivo. With chronic caffeine consumption, OCS users are predicted to have an increased steady-state plasma caffeine concentration as compared to non-OCS users.
Conduction threshold, switching, and hysteresis in quantum dot arrays.

We investigate low temperature transport in $200\ifmmode\times\else\texttimes\fi{}200$ arrays of GaAs quantum dots in which coupling between dots and electron density is controlled by a single gate. Current-voltage curves obey a power law above a threshold voltage with exponent $\ensuremath{\sim}1.5$, and show discontinuous and hysteretic jumps in the current, or ``switching events.'' Multiple switching events result in a hierarchy of hysteresis loops. Switching and hysteresis decrease with increasing temperature and disappear above 1 K. A possible mechanism for the hysteresis involving gate-to-dot tunneling is discussed.
Correlations between acute radiation scores and pain scores in canine radiation patients with cancer of the forelimb.

Abstract Objective To determine whether there is a correlation between skin acute radiation score (ARS) and pain scores and to determine if skin ARSs can be used to predict future pain scores and increased need for analgesia in dogs undergoing radiation therapy for cancer of the forelimb. Study design Prospective observational study. Animals Seven middle-aged dogs of various breeds with cancer of the forelimb. Methods Each neoplasm was surgically removed and a histologic diagnosis was obtained. Curative intent radiation therapy was initiated 2½–4½ weeks after surgery. Curative intent radiation therapy was delivered as prescribed. Two trained observers scored the dogs using a visual analog pain scale (VAS), Glasgow composite measure of pain scale, short form (GCMPS) and skin ARS prior to each day's therapy. Daily scores were averaged and scatter plots were developed. Generalized estimating equation regressions were used to calculate standard error, 95% confidence interval, and p -values for each relationship. Confidence and prediction bands were plotted. Results A statistically significant correlation between skin ARS and VAS and GCMPS pain scores was identified indicating that as the skin ARS increased so did the pain scores. A general correlation between VAS and GCMPS scores was observed. Early (fraction days 1–6) GCMPS scores were significantly influenced by anxiety behavior unrelated to pain. Skin ARS was found to predict precisely current and future presence of pain, but could only predict a range of potential future pain scores based on the pain management approach in use during this study. Conclusions Skin ARS can provide valuable information for initiating preemptive analgesia and intensifying pain management during curative intent radiation therapy. Daily pain scoring with an acceptable pain scale should be used in conjunction with the skin ARS to improve patient pain management. Clinical relevance Pain is an anticipated consequence of curative intent radiation therapy. Understanding the correlation between pain and skin ARS may facilitate more effective pain management.
On the core of linear production games

An economic production game is treated, in which players pool resources to produce finished goods which can be sold at a given market price. The production process is linear, so that the characteristic function can be obtained by solving linear programs.
Active collaborative permutation learning

We consider the problem of Collaborative Permutation Recovery, i.e. recovering multiple permutations over objects (e.g. preference rankings over different options) from limited pairwise comparisons. We tackle both the problem of how to recover multiple related permutations from limited observations, and the active learning problem of which pairwise comparison queries to ask so as to allow better recovery. There has been much work on recovering single permutations from pairwise comparisons, but we show that considering several related permutations jointly we can leverage their relatedness so as to reduce the number of comparisons needed compared to reconstructing each permutation separately. To do so, we take a collaborative filtering / matrix completion approach and use a trace-norm or max-norm regularized matrix learning model. Our approach can also be seen as a collaborative learning version of Jamieson and Nowak's recent work on constrained permutation recovery, where instead of basing the recovery on known features, we learn the best features de novo.
Molecular genetics of crustacean feeding appendage development and diversification

Arthropods dominate our seas, land, and air and have done so for hundreds of millions of years. Among the arthropods, crustaceans present us with a rich history of morphological change, much of which is still represented among extant forms. Crustacea largely interact with their environment via their appendages; thus vast amounts of variation exist among the different appendages of a single individual and between appendages from different species. Comparative studies of crustacean appendage development present us with an important story regarding the evolution of morphology over both relatively short (a few million years) and relatively long (a few hundred million years) evolutionary time scales. Recent studies have used the genetic and molecular data from Drosophila development to try to understand the molecular basis for some of the variations seen in crustacean limbs. Here we review some of these data based on the expression patterns of the genes Ultrabithorax, abdominal - A, Sex combs reduced, and Distal-less.
On the driving force of PAH production

The kinetic factors affecting the production of polycyclic aromatic hydrocarbons (PAH) in high-temperature pyrolysis and combustion environments are analyzed. A lumped kinetic model representing polymerization-type growth by one irreversible step and two reversible steps is considered. It is shown that at high temperatures, PAH growth is controlled by the superequilibrium of hydrogen atoms; at low temperatures and low H2 concentrations, the PAH growth rate is proportional to the rate of the H-abstraction of a hydrogen atom from aromatic molecules; while at low temperatures and high H2 concentrations, it is controlled by the thermodynamics of the H-abstraction and the kinetics of acetylene addition to aromatic radicals. The presence of oxygen mainly affects the small-molecule reactions during the induction period.
Drivers of information security search behavior: An investigation of network attacks and vulnerability disclosures

More and more people use search engines to seek for various information. This study investigates the search behavior that drives the search for information security knowledge via a search engine. Based on theories in information search and information security behavior we examine the effects of network attacks and vulnerability disclosures on search for information security knowledge by ordinary users. We construct a unique dataset from publicly available sources, and use a dynamic regression model to test the hypotheses empirically. We find that network attacks of current day and one day prior significantly impact the search, while vulnerability disclosure does not significantly affect the search. Implications of the study are discussed.
Mycobacterium avium enters a state of metabolic dormancy in response to starvation

Summary Members of the Mycobacterium avium complex (MAC) exhibit a highly effective and biphasic response to starvation, losing less than 90% viability after 2 years in deionized water. During the first adaptive phase of 4–7 days, the bacilli exhibit a burst of lipid catabolism, alteration of mycolate modifications, loss of catalase and urease activities, and a decline in sensitivity to antibiotics. There is also a decline in the protein level of alanine tRNA synthetase (AlaS), and an increase in ribonuclease E (Rne) levels. During the following persistence phase, the bacilli become metabolically dormant. However, with return of nutrients, the cells rapidly respond with increased activity, as determined by reduction of a tetrazolium dye. The primary reservoir for MAC is natural and municipal water, and the metabolic dormancy may be analogous to that of other aquatic organisms, such as vibrio. The organized metabolic shutdown that environmental mycobacteria utilize to survive starvation may have evolved into the host-specific dormancy mechanisms of Mycobacterium tuberculosis .
Beware expense reimbursement schemes

Your employees may be stealing your cash with clever expense reimbursement schemes that are difficult to spot. Reports of this kind of cash fraud appear in the press on a daily basis. What kinds of schemes are out there, and what can you do to prevent and detect them? © 2008 Wiley Periodicals, Inc.
Modes of Dissipation: The Green Episteme and Its Not-So-Green Psychopathologies

A forward looking alternative to the major past and present Western paradigms of psychological normativity and abnormality is outlined. This novel perspective is linked to the emerging moral power of “green” environmentalism and the immanent life and death struggle to reverse humanity’s fouling of the biosphere. An argument is advanced that such a conceptual re-framing of psychopathology requires foundational recourse both to Penrose’s theory of consciousness as wave function collapse and to a refinement of the anthropic principle. Implications for a possible future “geometric” taxonomy of mental illness are suggested.
Is Kripke really at The Helm

There is a very interesting phenomenon which takes place in philosophy. Theories which appeared ten or fifteen years ago in the literature of, say, the philosophy of language or the philosophy of mind, often make a reappearance in current discussions of problems in the philosophy of religion. As Yogi Berra once remarked, ‘It's deja vu all over again’. However, there is always a possibility that the transition from the earlier context to the later one will be less than smooth. For sometimes the theory reappears in a slightly distorted form, and, as a result, its bearing on the current discussion is somewhat misconceived. In this paper, an example of this phenomenon, and its potential problems, will be considered. Our purpose is not, of course, to discourage such intra-disciplinary dialogue in philosophy of religion, but rather to recommend that it be undertaken with a considerable measure of care.
Game theory and the practice of revenue management

Revenue management is a large and growing practice in industry. It involves much of what economists, computer scientists and applied mathematicians know and love: statistics, optimization, demand modeling and algorithm design. And strategic behavior is clearly of central importance to many pricing decisions. Despite all this, game theory is rarely used in revenue management practice. In this talk, we look at the potential role of game theory in revenue management and what challenges must be overcome to make it viable in practice.
X-Ray Magnetic Circular Dichroism Spectroscopy of Transition Metal Multilayers

Over the last few years the X-ray magnetic circular dichroism (XMCD) technique has evolved into an important magnetometry tool and the present article describes the principles and unique strengths of the technique. They are the quantitative determination of element-specific spin andorbital magnetic moments and their anisotropies through sum rule analysis of experimental spectra. In particular, we discuss applications of the XMCD technique to the study of transition metal multilayers. We show that a thin film of a non-magnetic metal like Cu may become magnetically alive and a thin film of a ferromagnetic metal like Fe may become magnetically dead. The anisotropy of the orbital magnetic moment is shown to be the microscopic origin of the magnetocrystalline anisotropy.
Photosynthetic pathway types of evergreen rosette plants (Liliaceae) of the Chihuahuan desert.

Diurnal patterns of CO2 exchange and titratable acidity were monitored in six species of evergreen rosette plants growing in controlled environment chambers and under outdoor environmental conditions. These patterns indicated that two of the species, Yucca baccata and Y. torreyi, were constituitive CAM plants while the other species, Y. elata, Y. campestris, Nolina microcarpa and Dasylirion wheeleri, were C3 plants. The C3 species did not exhibit CAM when grown in any of several different temperature, photoperiod, and moisture regimes. Both photosynthetic pathway types appear adapted to desert environments and all species show environmentally induced changes in their photosynthetic responses consistent with desert adaptation. The results of this study do not indicate that changes in the photosynthetic pathway type are an adaptation in any of these species.
Integrated Dynamic Simulation Model With Supervisory Control Strategy for a PEM Fuel Cell Hybrid Vehicle

System-level modeling and control strategy development for a hybrid fuel cell vehicle (HFCV) are presented in this paper. A reduced-order fuel cell model is created to accurately predict the fuel cell system efficiency while retaining dynamic effects of important reactant variables. The fuel cell system model is then integrated with a DC/DC converter, a Li-Ion battery, an electric drive and tire/vehicle dynamics to form a HFCV. The supervisory-level control problem of the HFCV is subsequently investigated. A stochastic dynamic programming (SDP) based approach is applied to obtain an optimal power management strategy. Simulations over different driving cycles showed that the SDP control strategy not only saved a significant amount of hydrogen but also produced smoother load for the fuel cell stack—both of which help the long term viability of the fuel cell technology for automotive applications.Copyright © 2004 by ASME
Gravity Powered Locomotion and Active Control of Two Simple Systems

The goal of this research is to develop energetically efficient robots that can produce stable gait. One cannot ignore the promise of robots that can walk by using very little energy. Gravity powered bipeds provide ample proof that this is possible. It is conceivable that mechanisms that are much simpler than legged robots can also produce gravity powered locomotion. It is also plausible that one can get deeper understanding of the dynamics of such simple mechanisms. In addition, evolutionary biology tells us that one can learn a great deal by studying the hereditary traits of organisms that evolve over generations. Thus, we study a chain of mechanisms that span from the very simple to the progressively more complicated. Each member derived from the previous one by making well defined incremental changes. Hence, our goal is to generate a family of planar mechanisms, with members that can be as simple as a bouncing ball or as complex as a five link biped. This presentation will be the first step of this study.Copyright © 2009 by ASME
Quincke's disease of the uvula

Upper airway compromise may be the result of numerous factors, among which a swollen uvula should be considered in the differential diagnosis. We present a case of a 21-year-old man who presented with complaints of throat discomfort, altered voice, and tachypnea secondary to acute uvular edema. The patient was treated with sympathomimetic drugs both by injection and by inhalation with complete resolution of the swelling and his symptoms within 30 minutes. The uvula is a potential cause of upper airway obstruction and should be examined in persons presenting with airway-related complaints.
Open-loop thermochemical cycles for the production of hydrogen

Abstract The concept of open-loop thermochemical cycles (cycles which have additional or other feedstocks than water and produce materials in addition to hydrogen and oxygen) is introduced. Preliminary analysis of possible feedstocks available indicates substantial quantities of hydrogen could possibly be produced through open-cycles. The advantages of open-cycles include the conversion of unwanted waste products to useful products while producing hydrogen. A compilation of open processes which would have SO 2 in addition to water as feedstock and which would produce sulfuric acid in addition to hydrogen and oxygen is given.
Sex-specific effects of diabetes on adverse outcomes after percutaneous coronary intervention: trends over time.

Background Diabetes is a stronger risk factor for coronary heart disease in women than in men. Whether diabetes also poses greater risks to women after percutaneous coronary intervention (PCI) has not been examined. Methods We examined 20586 PCI procedures at Emory University Hospitals (Atlanta, GA) between 1990 and 2003. Hazard ratios (HRs) for 1-year major adverse cardiac events were calculated comparing diabetic with nondiabetic patients by sex and study year. Data were adjusted for demographic and clinical factors using Cox proportional hazards models. Results Despite increasing patient age and comorbidity burden, diabetic and nondiabetic men had a significant improvement in PCI outcomes between 1990 and 2003 ( P P = .073), but not nondiabetic women ( P = .206). Overall, diabetes had a stronger association with adverse outcomes in women (HR 1.93, 95% CI 1.55-2.40) than in men (HR 1.26, 95% CI 1.09-1.47) ( P = .002 for the interaction between sex and diabetes). The excess risk associated with diabetes in women, however, was largely driven by early study years (1990-1993). This excess risk associated with diabetes in women declined over time, and diabetes had a similar effect on outcomes in both women and men in more recent years ( P = .010 for the interaction between sex, diabetes, and time). Conclusions Percutaneous coronary intervention outcomes of diabetic and nondiabetic men have improved in recent years. However, among women, diabetic patients had greater improvements in outcomes after PCI compared with nondiabetic patients. As a result, diabetes is no longer a stronger risk factor for adverse outcomes after PCI in women than in men.
Exposure and Health Risk from Swimming in Outdoor Pools Contaminated by Trichloroethylene

ABSTRACT A method was developed that evaluated the exposure and health risk to children from swimming in outdoor pools filled with contaminated water. It was found that dermal absorption of trichloroethylene (TCE) was significantly larger than the inhalation component of the exposures. It was estimated that the inhalation route accounted for only 1% of the total exposure, whereas accidental ingestion was 7% of the child's total intake and the dermal absorbed dose was 92% of the total exposure. The relative percentage of the total exposure estimated for each exposure route indicated that the dermal exposure route and accidental ingestion of pool water should not be ignored for volatile compounds when evaluating exposure. The method utilized was simple enough to use computer spreadsheets for the calculations and can be easily adapted to various swimming scenarios and age groups. This method also included an assessment of the uncertainty in the exposure and risk estimates. The range of estimated exposures wa...
The Complexation of Ferrocene Derivatives by a Water-Soluble Calix[6]arene

The complexation of several ferrocene derivatives by the water-soluble host p-sulfonato-calix[6]arene was investigated using electrochemical and 1H-NMR spectroscopic techniques. The electrochemical results indicate that both oxidation states of the guests are bound to the calixarene host, although the oxidized (ferrocenium) forms are complexed more strongly than the reduced (ferrocene) species. 1H-NMR spectroscopic data indicate that the complexation phenomena involves the inclusion of the guest’s ferrocene moiety into the flexible calixarene cavity.
Parallels, particularities, problems and positive possibilities related to institutional sexism and racism

Synopsis Examples of institutions are given, and definitions of racism, sexism and institutional racism and sexism are provided. Research and theoretical literature are cited in order to illustrate that many parallels, or similarities, exist in regards to discrimination against females and minorities, especially Black Americans, in the United States. Also cited is literature which indicates that, despite the parallels, there are substantial differences, or particularities, in practices or conditions related to racism and sexism, American style. Problems facing minorities and women in the fight to eliminate racism and sexism are highlighted, and research is given to support an opinion that the power structure maintained by Caucasian males is the basic barrier to racial and sexual equality. Ten possible solutions are offered to minorities and/or women for solving problems resulting from institutional racism and sexism as well as from general societal-economic conditions. The solutions require individual and organizational levels of action.
Portrait of Success: Cooperating Teachers and the Student Teaching Experience

Abstract Current research on student teachers and the student teaching experience often has neglected the point of view of the cooperating teachers. Through interviews with 20 cooperating teachers, the researcher obtained data on how cooperating teachers define a successful student teaching experience and what they believe could enhance their success as student mentors. The data from the interviews confirm certain trends in these perceptions, including the importance of a “mutual learning relationship” between the student and cooperating teacher. Cooperating teachers also called for greater support and collaboration from the university community, defined by (a) improved communication about university expectations, (b) more courses and inservicing for cooperating teachers, (c) more input from cooperating teachers about the content and delivery of methods courses, and (d) more input from cooperating teachers in the development of teacher education programs. The author concludes that more effective teacher e...
Determining the Orientation of Protegrin-1 in DLPC Bilayers Using an Implicit Solvent-Membrane Model

Continuum models that describe the effects of solvent and biological membrane molecules on the structure and behavior of antimicrobial peptides, holds a promise to improve our understanding of the mechanisms of antimicrobial action of these peptides. In such methods, a lipid bilayer model membrane is implicitly represented by multiple layers of relatively low dielectric constant embedded in a high dielectric aqueous solvent, while an antimicrobial peptide is accounted for by a dielectric cavity with fixed partial charge at the center of each one of its atoms. In the present work, we investigate the ability of continuum approaches to predict the most probable orientation of the β-hairpin antimicrobial peptide Protegrin-1 (PG-1) in DLPC lipid bilayers by calculating the difference in the transfer free energy from an aqueous environment to a membrane-water environment for multiple orientations. The transfer free energy is computed as a sum of two terms; polar/electrostatic and non-polar. They both include energetic and entropic contributions to the free energy. We numerically solve the Poisson-Boltzmann equation to calculate the electrostatic contribution to the transfer free energy, while the non-polar contribution to the free energy is approximated using a linear solvent accessible surface area relationships. The most probable orientation of PG-1 is that with the lowest relative transfer free energy. Our simulation results indicate that PG-1 assumes an oblique orientation in DLPC lipid bilayers. The predicted most favorable orientation was with a tilt angle of 19°, which is in qualitative agreement with the experimentally observed orientations derived from solid-state NMR data.
Fatigue Crack Propagation Mechanisms Of Long And Small Cracks In Al-Si-Mg And Al-Mg Cast Alloys

Fatigue crack growth of long and small cracks was investigated for various Al-Si-Mg and Al-Mg cast alloys. Low residual stress was ensured during processing to concentrate on microstructural effects on crack growth. Compact tension and single edge tension specimens were fatigue crack growth tested at room temperature and stress ratio, R = 0.1. Microstructure related mechanisms were used to explain the near-threshold behaviour and crack growth response in Regions II and III for each material considering relevant microstructural features such as SDAS, grain size, and volume fraction and morphology of eutectic Si. Threshold behaviour of long cracks is attributed to closure-dependent mechanisms. In Regions II and III, the changes in crack growth mechanisms were explained through correlations between the extent of the plastic zone ahead of the crack tip and material-specific microstructural damage. Threshold behaviour of small cracks is explained through closure-independent mechanisms, specifically through the barrier effects of controlling microstructural characteristics specific to each material. Recommendations for integrating materials knowledge in structural design for fatigue performance are given.
Numerical Simulation of Dispersion of Fire Extinguishing Agents in Turbulent Flow in the Presence of Clutter Elements of Aircraft Engine Nacelles

The combination of highly turbulent airflow, flammable fluids, and numerous ignition sources makes aircraft engine nacelles a difficult fire zone to protect. Better understanding of nacelle air flow and how it influences the spread of fires and fire extinguishing agents is needed to improve the efficiency of fire suppression. The principal objective of this study is to analyze the flow field and the dispersion of fire extinguishing agents in the presence of various clutter elements of aircraft engine nacelles. Three dimensional simulations of the transport of liquid droplets in highly turbulent flow past clutter elements are performed in this study. A three dimensional model with 2000 mm length, 915 mm width and 610 mm height was first created. The clutter package consists of 16 cylindrical elements; each element has an outer diameter D of 50.8 mm and assembled to form three separate arrays of 5, 6 and 5 elements. The stream wise spacing between each clutter array is set to twice the diameter (2 D). The three dimensional geometry is similar to the one used in the experimental study at Sandia National Laboratory. This will help to validate the numerical results before performing a parametric study. Water with initial droplet size of 150 to 280 μm, and flow rate of 0.285 Kg/s is used as suppressant agent. The three velocity components, turbulence intensity, and droplet concentrations and trajectories behind the clutter package are obtained in this study. The droplet X-velocity and Y-velocity and the droplet size distribution downstream the clutter elements show a good agreement with the experimental data. The effect of initial turbulence intensity, the air flow velocity at the inlet, and droplet diameter at the injection on the transport and dispersion of fire extinguishing agent in this complex geometry is presented in this paper.© 2009 ASME
Blume-Emery-Griffiths model on the honeycomb lattice

Exact results are obtained for a spin-1 system on the honeycomb lattice with the Blume-Emery-Griffiths Hamiltonian −ℋ/kT =J∑i,jSiSj+K∑〈i,j〉Si2j2−Δ∑iSi2+H∑Si subject to the constraintK=−ln coshJ. ForJ>0, the system behaves like a spin-1/2 Ising ferromagnet with the free energy analytic everywhere except at the first-order phase boundaryH=0, tanhJ<(2+eΔ)/\(\sqrt 3 \). Derivatives of the free energy across this boundary are discontinuous and we obtain the exact expression for the spontaneous magnetization. ForJ<0, the system can be transcribed into an antiferromagnetic spin-1/2 Ising model in a real magnetic field, and from this equivalence portions of the exact phase boundary are determined.
GOPHER-PLANT-FUNGAL INTERACTIONS AFFECT ESTABLISHMENT OF AN INVASIVE GRASS

Many attempts have been made to link invasions of exotic plants to specific plant traits and key attributes of invaded ecosystems. While these factors play a role in determining the potential for invasion, they are often inadequate in predicting the success of a specific invasion. We show that interactions of an invasive grass with other members of the community determine the local pattern of invasion. A fungus, Ulocladium atrum, aids the establishment of barbed goatgrass (Aegilops triuncialis) by weakening the grass's tough seed head, thereby accelerating germination and seedling establishment. In contrast, gophers, Thomomys bottae, decrease establishment of this invader by selectively burying patches of goatgrass seedlings under mounds. Plants that survive these gopher disturbances produce seeds that are uninfected by Ulocladium atrum, which may further decrease the establishment of the next generation of goatgrass. A field survey indicated that goatgrass achieves dominance in areas with minimal gopher disturbance, but has limited establishment in pastures with high gopher activity, indicating that the landscape pattern of gopher activity influences patterns of goatgrass invasion by manipulating gopher-plant-fungal interactions.
Dural afferents express acid-sensing ion channels: A role for decreased meningeal pH in migraine headache

Migraine headache is one of the most common neurological disorders. The pathological conditions that directly initiate afferent pain signaling are poorly understood. In trigeminal neurons retrogradely labeled from the cranial meninges, we have recorded pH-evoked currents using whole-cell patch-clamp electrophysiology. Approximately 80% of dural-afferent neurons responded to a pH 6.0 application with a rapidly activating and rapidly desensitizing ASIC-like current that often exceeded 20nA in amplitude. Inward currents were observed in response to a wide range of pH values and 30% of the neurons exhibited inward currents at pH 7.1. These currents led to action potentials in 53%, 30% and 7% of the dural afferents at pH 6.8, 6.9 and 7.0, respectively. Small decreases in extracellular pH were also able to generate sustained window currents and sustained membrane depolarizations. Amiloride, a non-specific blocker of ASIC channels, inhibited the peak currents evoked upon application of decreased pH while no inhibition was observed upon application of TRPV1 antagonists. The desensitization time constant of pH 6.0-evoked currents in the majority of dural afferents was less than 500ms which is consistent with that reported for ASIC3 homomeric or heteromeric channels. Finally, application of pH 5.0 synthetic-interstitial fluid to the dura produced significant decreases in facial and hind-paw withdrawal threshold, an effect blocked by amiloride but not TRPV1 antagonists, suggesting that ASIC activation produces migraine-related behavior in vivo. These data provide a cellular mechanism by which decreased pH in the meninges following ischemic or inflammatory events directly excites afferent pain-sensing neurons potentially contributing to migraine headache.
Discovery of AICAR Tfase inhibitors that disrupt requisite enzyme dimerization

Abstract The discovery of a new class of aminoimidazole carboxamide ribonucleotide transformylase (AICAR Tfase) inhibitors through screening peptidomimetic libraries (>40,000 compounds) that act by inhibiting requisite enzyme dimerization is disclosed. In addition to defining key structural features of the lead compounds responsible for the activity, kinetic analysis of the remarkably small inhibitors established that they act as noncompetitive, dissociative inhibitors of AICAR Tfase with the prototypical lead (A1B3, Cappsin 1) exhibiting a Ki of 3.1 ± 0.3 μM. Thus, the studies define a unique approach to selectively targeting AICAR Tfase over all other folate-dependent enzymes, and it represents only one of a few enzymes for which inhibition achieved by disrupting requisite enzyme dimerization has emerged from screening unbiased combinatorial libraries.
Thermal reversal of elongated ferromagnetic particles misoriented to the applied field

The energy barrier to be overcome for thermal reversal, the reversal mode and the effective particle volume involved are determined by the saddle points of the energy surface. We investigate the influence of field misorientation, exchange-coupling and magnetostatic interaction for a 2:1 aspect ratio particle discretized into two subunits. Typically, increasing the field angle from 0/spl deg/ to 45/spl deg/ enhances the effective volume in both cases by more than 20%.
Simulation of Whispering-Gallery Mode Microsensing in a Microfluidic System

Label-free detection using a whispering-gallery mode biosensor in a micro fluidic channel is simulated. The analyte transport in the solution is controlled by applied electric potentials and diffusion. The finite element method is employed for solving the charged species transportation equations, the Poisson equation, the equations of conservation of momentum and energy, and the Helmholtz equations for electromagnetic waves. The adsorption process of analyte on the micro resonator surface is monitored by the resonance wavelength shift in the sensor. Shift caused by temperature variation due to Joule heating is found to be negligible compared to that induced by analyte deposition. The deposition induced shifts behave in a manner similar to Langmuir-like adsorption kinetics. A linear correlation between the frequency shift and the analyte concentration in the solution is obtained. The applied voltage is found to affect the adsorption capability; and thus, the sensor sensitivity. Detection of very low concentration to the sub-ppm level using the sensor is demonstrated.Copyright © 2009 by ASME
Kinetics and stereochemical control of propylene polymerization initiated by ethylene bis(4,5,6,7‐tetrahydro‐1‐indenyl) zirconium dichloride/methyl aluminoxane catalyst

The kinetics and sterochemical control of propylene polymerization initiated by rac-ethylene bis (4,5,6,7-tetrahydro-1-indenyl) zirconium dichloride/methyl aluminoxane (1/MAO) and by rac-ethylene bis (1-indenyl) zirconium dichloride/MAO (2/MAO) were investigated. The polymerization activities increase monotonically with temperature corresponding to an overall activation energy of 10.6 kcal mol−1. This is accompanied, however, by reduction of stereochemical control as reflected in the amount of the polypropylene (PP) soluble in low boiling solvent. At a temperature of 30°C and higher, polymerization initiated by 1/MAO produced no PP insoluble in refluxing n-heptane. Tritium radiolabeling showed that at [Al]/[Zr] ≥ 3500 and 30°C, two-thirds of 1 becomes catalytically active. There are at least two kinds of active species formed in about equal amounts; one has more stereoselectivity, 10–20 times greater rate constant of propagation, and a factor of 5–15 faster chain transfer to MAO than the second kind of Active species. This is also true at low [Al]/[Zr] of 350, except that the total amount of the two active species corresponds to only 13% of the [1]. Replacement of MAO with trimethyl aluminum resulted in the decrease of stereoselectivity and loss of catalytic activity proportional to the amount of replacement. A comparison was made with the polymers obtained with 2/MAO.
Antenatal maternally-administered phosphodiesterase type 5 inhibitors normalize eNOS expression in the fetal lamb model of congenital diaphragmatic hernia.

Purpose Pulmonary hypertension (pHTN), a main determinant of survival in congenital diaphragmatic hernia (CDH), results from in utero vascular remodeling. Phosphodiesterase type 5 (PDE5) inhibitors have never been used antenatally to treat pHTN. The purpose of this study is to determine if antenatal PDE5 inhibitors can prevent pHTN in the fetal lamb model of CDH.