cssi/SciSciGPT-SciSciNet huggingface dataset:
Improving the sensitivity of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry by using polyethylene glycol modified polyurethane MALDI target

Previous studies in our group have shown that the analyte signal in a matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) experiment is strongly influenced by the binding interactions between the target surface and the analyte. Specifically, the analyte signal increases with decreases in surface binding affinity, which has been attributed to more unbound analyte being available for incorporation within the MALDI matrix. In this work, polyethylene glycol (PEG) was chemically grafted onto a polyurethane (PU) film to produce a MALDI target having reduced surface-protein binding affinity, and the effect of this modification on protein MALDI ion signals was investigated. The proteins myoglobin, lysozyme, and albumin were used to evaluate the PEG PU modified target as compared with a PU target and a commercial stainless steel target. It is shown that there are enhancements in the protein MALDI ion signals on the PEG PU modified target and that the limit of detection for these proteins is decreased by a factor of 2 to 6 in comparison with the unmodified PU and the commercial stainless steel targets.
Crystal-field splitting in icosahedral symmetry.

The crystal-field splitting of rare-earth ions in icosahedral symmetry is treated by group-theoretical and numerical methods. From the crystal-field Hamiltonian, which is governed by only one crystal-field parameter, the crystal-field splitting schemes of all rare-earth ions in their Hund's-rule ground state are derived. It is shown that these schemes are expected to survive in quasicrystals as well as in metallic glasses. The derived temperature dependence of the surplus static susceptibility and specific heat, as generated by the icosahedral crystal-field splitting, is discussed and plotted for selected cases.
Intersection Numbers of Sections of Elliptic Surfaces

The theory of elliptic surfaces over C draws on ideas and techniques from arithmetic, geometry and analysis. Let f : X ~ S be a minimal elliptic fibration with non-constant j-invariant, which possesses a section ao. Then the group of sections of f can be naturally identified with the group of rational points of the generic fiber; i.e., ~ consists of rational solutions of a cubic equation over a function field. On the analytic end, one can associate to these sections certain generalized automorphic forms which have a natural pairing (the Eichler bilinear form) defined on them. In this paper, we will examine the connection of these topics with the geometry of X via the intersection product and Hodge decomposition on its cohomology. This paper had its origin in a problem posed by W. Hoyt: if the rank r of the group ~ of sections is known (e.g., when pg =0) and one has r sections al . . . . . err, do they form a basis of ~ modulo torsion'? The earlier attempt by Hoyt and Schwartz to answer this question involved a direct use of the Eichler pairing. Its values lie in (1/N)Z for some N e Z , and a bound for the best value of N can be computed from the monodromy. Thus, by looking at the discriminant of this form on the given sections, one obtains a sufficient (though not always necessary) condition for them to be generators modulo torsion. The hope had been that one would be able to compute this discriminant in examples. However, the calculations are very messy and have been done only in the simplest of cases. Another difficulty in this program is that sometimes one must base-change before the Eichler pairing can be defined. We give an alternate method (using intersection numbers on X) for doing such computations (w and we will use it to compute a large number of examples (w In w we will show how our geometric methods relate to the automorphic forms and Eichler pairing, and we also determine the role they play in the Hodgc theory of X. Now we discuss the contents of the paper in greater detail. Given f : X ~ S as described above, let f : X--*S be the smooth part of f (throw away the singular
Characterizing intersection classes of graphs

Abstract A graph is an intersection graph if it is possible to assign sets to its vertices so that adjacency corresponds exactly to nonempty intersection. If the sets assigned to vertices must belong to a pre-specified family, the resulting class of all possible intersection graphs is called an intersection class. We characterize intersection classes. The main result is generalized for classes in which the assignment of sets to vertices must be one-to-one, as well as for classes of simplicial complexes arising as nerves of sets from a pre-specified family.
Learning Kernels for Unsupervised Domain Adaptation with Applications to Visual Object Recognition

Domain adaptation aims to correct the mismatch in statistical properties between the source domain on which a classifier is trained and the target domain to which the classifier is to be applied. In this paper, we address the challenging scenario of unsupervised domain adaptation, where the target domain does not provide any annotated data to assist in adapting the classifier. Our strategy is to learn robust features which are resilient to the mismatch across domains and then use them to construct classifiers that will perform well on the target domain. To this end, we propose novel kernel learning approaches to infer such features for adaptation. Concretely, we explore two closely related directions. In the first direction, we propose unsupervised learning of a geodesic flow kernel (GFK). The GFK summarizes the inner products in an infinite sequence of feature subspaces that smoothly interpolates between the source and target domains. In the second direction, we propose supervised learning of a kernel that discriminatively combines multiple base GFKs. Those base kernels model the source and the target domains at fine-grained granularities. In particular, each base kernel pivots on a different set of landmarks--the most useful data instances that reveal the similarity between the source and the target domains, thus bridging them to achieve adaptation. Our approaches are computationally convenient, automatically infer important hyper-parameters, and are capable of learning features and classifiers discriminatively without demanding labeled data from the target domain. In extensive empirical studies on standard benchmark recognition datasets, our appraches yield state-of-the-art results compared to a variety of competing methods.
A linearized DC lamp controller

The design of a simple and inexpensive battery powered lamp controller for microscope lamps commonly used in patch clamp and other biophysical studies is described. The circuit linearizes the normally exponential voltage-intensity curve of standard 12-V lamps by using an operational amplifier to provide feedback to the drain of a power MOSFET. When the unit is turned off, a charging circuit recharges the battery at a constant potential until the battery voltage reaches a preset level. The charging voltage is then reduced to balance the self-discharge rate of the battery.
Effect of turbulence and devolatilization models on coal gasification simulation in an entrained-flow gasifier

Abstract Numerical simulations of the oxygen-blown coal gasification process inside a generic entrained-flow gasifier are carried out. The Eulerian–Lagrangian approach is applied to solve the Navier–Stokes equations and the particle dynamics. Seven species transport equations are solved with three heterogeneous global reactions and two homogeneous reactions. Finite rates are used for the heterogeneous solid-to-gas reactions. Both finite rate and eddy-dissipation combustion models are calculated for each homogeneous gas-to-gas reaction, and the smaller of the two rates is used. Four different devolatilization models are employed and compared. The Kobayashi model produces slower devolatilization rate than the other models. The constant rate model produces the fastest devolatilization rate. The single rate model and the chemical percolation model produce moderate and consistent devolatilization rate. Slower devolatilization rate produces higher exit gas temperature and higher CO and CO 2 mass fractions, but lower H 2 and heating value, and hence, achieves lower gasification efficiency. Combustion of volatiles is modeled with two-stage global reactions with an intermediate stage via benzene. Turbulence models significantly affect the simulated results. Among five turbulence models employed, the standard k – e and the RSM models give consistent results. The time scale for employing stochastic time tracking of particles also affects simulated result. Caution has to be exerted to select the appropriate time constant value. Smaller particles have a higher surface/volume ratio and react faster than larger particles. However, large particles possessing higher inertia could impinge on the opposing jet and change the thermal-flow filed and the reaction rates.
Environmental health moves into the 21st century.

Abstract Over the past half century, environmental health research has branched from a descriptive, observational process into one of hypothesis driven and mechanistically based science. Nevertheless, the meaning of observed effects of exposures in experimental systems to human public health remains elusive. Recent advances in genetics and ”omics“ hold great promise to further our abilities to assess potential human health effects and to manage exposures properly. But the comfort of 100% certainty will not be available in the foreseeable future, leaving us with the challenge of designing relevant experiments and test systems upon which to base ”logical“ policy in risk management.
The Changing Role of the Embryo in Evolutionary Thought: Roots of Evo-Devo

1. Introduction Part I. Darwin's Century: Beyond the Essentialism Story: 2. Systematics and the birth of the natural system 3. The origins of morphology, the science of form 4. Owen and Darwin, the archetype and the ancestor 5. Evolutionary morphology: the first generation of evolutionists 6. Interlude Part II. Neo-Darwin's Century: Explaining the Absence and the Reappearance of Development in Evolutionary Thought: 7. The invention of heredity 8. Basics of the evolutionary synthesis 9. Structuralist reactions to the synthesis 10. The synthesis matures 11. Recent debates and the continuing tension.
Hydroxyl tagging velocimetry (HTV) in experimental air flows

The new nonintrusive instantaneous molecular flow tagging method, hydroxyl tagging velocimetry (HTV), previously demonstrated only for high-temperature reacting flows, is now demonstrated in low-temperature (300 K) ambient air flowfields. Single-photon photodissociation of ground-state H2O by a ∼193-nm ArF excimer laser ‘writes’ very long grid lines (>50 mm) of superequilibrium OH and H photoproducts in a room air flowfield due to the presence of ambient H2O vapor. After displacement, the positions of the OH tag lines are revealed through fluorescence caused by A2Σ+ (ν′=0)?X2Πi (ν′′=0) OH excitation using a pulsed frequency-doubled dye laser with an operating output wavelength of ∼308 nm. The dye ‘read’ laser accesses the strong Q1(1) line, compensating for the relatively weak 193-nm absorption of room-temperature H2O. The weak absorption of ground vibrational state H2O has previously precluded the use of HTV at low temperatures, since previous HTV systems relied on a KrF excimer ‘read’ laser that could only access a weak (3?0) OH transition. The instantaneous velocity field is determined by time-of-flight analysis. HTV tag lifetime comparisons between experimental results and theoretical predictions are discussed. Multiple-line tag grids are shown displaced due to an experimental air flowfield, thus providing 2-D multipoint velocity information. Due to the instantaneous nature of the HTV tag formation, HTV is particularly suitable for, but not limited to, a variety of fast flowfield applications including nonreacting base flows for high-speed projectiles and low-temperature hypersonic external or internal flows.
Rotational excitation in molecular collisions: statistical features of the S-matrix

Abstract The energy dependence of the phase of the transition amplitude is used to discuss the statistical approximation, thereby suggesting an experimental distinction between the strong coupling and the collision complex models. Computational results for Xe - D 2 and He - N 2 collisions are presented.
SOIL BIOTA FACILITATE EXOTIC ACER INVASIONS IN EUROPE AND NORTH AMERICA

The primary hypothesis for successful exotic plant invasions is that the invaders have escaped the specialist consumers that control them (Enemy Release Hypothesis). However, few studies have rigorously tested this assertion with biogeographical experiments or considered the effects of soil organisms. We tested the Enemy Release Hypothesis and the enhanced role of mutualisms by comparing density patterns of the North American Acer negundo and European A. platanoides trees in their native and nonnative ranges. Invaders that have escaped their natural enemies are predicted to attain greater densities in nonnative than native ranges. To determine whether interactions with soil biota could explain the population distributions observed in the field, we compared the effects of sterilized and nonsterilized soil associated with Acer and non-Acer trees in native and nonnative ranges on the growth of seedlings in the greenhouse. In the field study, distances from focal trees to the nearest Acer conspecifics were 56– 77% less in their nonnative ranges than in their native ranges. In the greenhouse experiment, the effect of soil biota also differed between native and nonnative ranges of Acers. Relative to sterilized controls, soil associated with conspecifics and heterospecifics from the native ranges decreased the total biomass and relative change in height of Acer seedlings by 35% and 40%, respectively. Soil associated with conspecifics in the nonnative ranges decreased the biomass and relative change in height of Acer seedlings by 112% and 64%, respectively; but the soil associated with heterospecifics in the nonnative ranges increased biomass and relative change in height of Acer seedlings by 13% and 37%, respectively. Our results suggest that invasion of Acers is enhanced by soil biota associated with dominant native species and that the soil biota effect becomes more inhibitory as the Acers establish. The relative difference in soil biota effects between ranges supports the Enemy Release Hypothesis but also suggests that mutualists are relatively more beneficial to Acers in their nonnative ranges than in their native ranges. Mutualisms may be relatively more beneficial in nonnative ranges because the invader has escaped from the negative effect of natural enemies that may attenuate the positive effect of mutualists.
Technology Innovations In Undergraduate Nutrition and Dietetics Education and Training

Abstract As education moves into the information technology age, dietetics and nutrition training must adapt to new instructional methods and the opportunities of distance learning. Innovative approaches to teaching nutritional biochemistry can help students learn and retain complex information and understand how nutrition relates to human health and disease. This approach has already been taken in US medical schools (110 of 129 have the Nutrition In Medicine ® interactive CD-ROM series). With a grant from the USDA and private industry, we are adapting this series of modules for use in both introductory nutrition classes as well as advanced dietetics student training and education. This technology offers significant flexibility in implementation (distance learning, independent study, learning laboratories, group instruction). The Medical Nutrition Curriculum Initiative is expanding its scope to provide an easily transportable curriculum to US dietetics programs and colleges and universities offering human nutrition courses. The series of interactive CD-ROM programs spans ten clinical topics: Nutritional Anemias, Stress, Cancer, Cardiovascular Disease, Diabetes, Maternal and Infant, Childhood and Adolescence, Aging, Nutritional Supplements and Fortified Foods, and Sports Nutrition. Nutritional biochemistry relevant to health and disease, dietary recommendations for treatment and preventive care, and related clinical issues are covered. The virtual case enables the student to practice nutrition-related skills in a patient setting. The introductory nutrition version targets first- or second-year nutrition students and includes a nutrition video game. The dietetics training version aims at senior or graduate nutrition students and has a stronger medical nutrition therapy emphasis within a nutritional biochemistry context. To maximize their effectiveness as educators of the next generation of nutrition professionals, nutrition and dietetics educators must be aware of the new advanced technology opportunities available in nutrition education and training.
Low-cost Cu 2 ZnSnS 4 thin films for large-area high-efficiency heterojunction solar cells

Cu 2 ZnSnS 4 (CZTS) thin films have been deposited on soda-lime glass (SLG) and Mo-coated SLG substrates using a low-cost spray pyrolysis technique followed by sulfurization under H 2 S flow at 540°C. Aqueous solution containing CuCl, ZnCl 2 , SnCl 4 and thiourea was used as precursor. Spray deposition was carried out at three different substrate temperatures of 280°C, 360°C and 440°C. Deposition conditions were optimized to obtain the best film properties. Structural, morphological and compositional analysis of the as-deposited and sulfurized CZTS films were carried out by x-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive x-ray spectroscopy (EDX) and x-ray photoelectron spectroscopy (XPS). Optical and electrical properties were measured by UV-Vis spectroscopy, van der Pauw and Hall effect measurements. XRD spectra confirmed the formation of kesterite CZTS films. Grown CZTS films showed an absorption coefficient >104 cm−1 and the bandgaps were found to lie between 1.42–1.72 eV at room temperature depending on deposition conditions and post deposition sulfurization treatments. All films were found to be of p-type conductivity with an average carrier concentration in the order of 1018–1020 cm−3. Optimum quality films were obtained for films fabricated at 360°C and no secondary phases were observed. n-CdS window layer was deposited on p-CZTS films prepared at 360°C substrate temperature to fabricate p-CZTS/n-CdS heterojunction solar cells. The heterojunction exhibited an open-circuit voltage (V OC ) of 290 mV and a short-circuit current density (J SC ) of 3.1 mA/cm2 under AM 1.5 illumination. Details of CZTS thin film fabrication, processing, and characterization results are presented.
Direct monitoring of silane/epoxy interphase chemistry

Abstract Evanescent wave spectroscopy has been used to directly monitor the interactions between an epoxy resin and an amino silane coupling agent, γ-aminopropyltrimethoxy silane (γ-APS) adsorbed on silica fibers. First, it was shown that reactions of the adsorbed silane molecules could be monitored as a function of drying at elevated temperature. Next, the silane surface treated fibers were embedded in the epoxy resin and the primary amine reactivity of the silane at 70°C was measured by the decrease from the initial absorbance height of the combination band at 4925 cm −1 . It was found that there was a decrease of 13% in band absorbance when the silane was adsorbed from a 5% γ-APS solution. The percent decrease was 22% and 38% when the silane was adsorbed from 2% and 1% γ-APS solutions, respectively. The results show that a significant fraction of the amine groups remain unreacted, even in the presence of excess epoxy. Also, it was discovered that in no instance was there any indication of silane diffusion from the interphase during the course of the experiment, even when the adsorbed silane was not dried at elevated temperature, prior to placement in the epoxy resin.
Training in and knowledge of terminal care in medical students and junior doctors

A survey of medical students and junior doctors shows a lack of training and knowledge in the care of dying patients and symptom control. The need for an increased emphasis on this training is identified.
Characterization of GaAs/Si Interface Structure by X-Ray Diffraction

By measuring the intensity profiles along the crystal truncation rods of a Si(001) substrate, we obtain the depth sensitivity necessary for x-ray diffraction measurements of the structure of its interface with a thick GaAs overlayer which is epitaxial to, but not in registry with the substrate. By comparing the diffraction with a model based on a grid of misfit dislocations, we find that the atoms at the interface have a root mean square displacement of 1.09┴0.1 A from this ideal structure, and that the interface has a roughness of 2.9┴1 A. The diffraction indicates an anomalously small strain perpendicular to the interface in the GaAs near the interface.
Power-limiting breakdown effects in GaAs MESFET's

State-of-the-art GaAs MESFET'S exhibit an output power saturation as the input power is increased. Experiments indicated that this power saturation is due to the combined effects of forward gate conduction and reverse gate-to-drain breakdown. This reverse breakdown was studied in detail by performing two-dimensional numerical simulations of planar and recessed-gate FET's. These simulations demonstrated that the breakdown occurs at the drain-side edge of the gate. The results of the numerical simulations suggested a model of the depletion layer configuration which could be solved analytically. This model demonstrated that the breakdown voltage was inversely proportional to the product of the doping level and the active layer thickness.
Volvulus of the splenic flexure: report of a case.

A case of volvulus of the splenic flexure occurring in a patient with regional ileitis and lactase deficiency is presented. The pertinent features of 12 previously reported cases are reviewed. Awareness of this rare cause of colonic obstruction and its radiographic presentation are important in the proper management of these patients.
Directly and indirectly detected through-bond heteronuclear correlation solid-state NMR spectroscopy under fast MAS

Two-dimensional through-bond (1)H{(13)C} solid-state NMR experiments utilizing fast magic angle spinning (MAS) and homonuclear multipulse (1)H decoupling are presented. Remarkable efficiency of polarization transfer can be achieved at MAS rates exceeding 40 kHz, which is instrumental in these measurements. Schemes utilizing direct and indirect detection of heteronuclei are compared in terms of resolution and sensitivity. A simple procedure for optimization of (1)H homonuclear decoupling sequences under these conditions is proposed. The capabilities of these techniques were confirmed on two naturally abundant solids, tripeptide N-formyl-L-methionyl-L-leucyl-L-phenylalanine (f-MLF-OH) and brown coal.
The finite element method for prediction of crack behavior

Abstract A direct method of computation of the stress intensity factor, K , of linear fracture mechanics is discussed. Poor accuracy of the method, unless extremely small elements are used near the crack tip, leads to its abandonment in favor of direct computation of the strain energy release rate which is equivalent to K . This procedure consists of computing the strain energy for two slightly different crack lengths and employing numerical differentiation to determine the strain energy release rate. The accuracy is quite good for a relatively coarse finite element mesh for the example problems presented. Finally the question of bounds to the true solution is considered and it is suggested, but not proved, that the method will always bound the solution in a manner depending on whether the stress intensity factor increases or decreases with crack length growth.
On the Objects of Speech Perception

From both direct-realist and motor-theoretic perspectives, the objects of speech perception are construed as articulatory events. We offer the alternative view that it is the auditory properties of phonetic events to which listeners are primarily sensitive. Evidence for this alternative view comes from a variety of sources, including studies of phonetic and phonological universals, comparisons of the perception of speech and nonspeech signals, cross-language perceptual experi- ments, and studies of phonetic categorization by nonhuman animals.
Hydrocephalus and arachnoid cysts

Aim The management of arachnoid cysts (AC) remains controversial. An additional problem derives from the management of hydrocephalus associated with an AC. In this work, we discuss existing procedures proposed in the current literature for their treatment.
Complications of Endomyocardial biopsy in children

Abstract OBJECTIVES To evaluate the incidence of, and risk factors for, complications of endomyocardial biopsy in children. BACKGROUND Endomyocardial biopsy (EMB) is a low risk procedure in adults, but there is a paucity of data with regard to performing this procedure in children. METHODS Retrospective review of the morbidity and mortality of 1,000 consecutive EMB procedures. RESULTS One thousand EMB procedures (right ventricle 986, left ventricle 14) were performed on 194 patients from July 1987 through March 1996. Indications for EMB included heart transplant rejection surveillance (846) and the evaluation of cardiomyopathy or arrhythmia for possible myocarditis (154). Thirty-seven (4%) procedures were performed on patients receiving intravenous inotropic support. There was one biopsy related death, secondary to cardiac perforation, in a two-week-old infant with dilated cardiomyopathy. There were nine perforations of the right ventricle, eight occurring in patients with dilated cardiomyopathy and one in a transplant recipient. The transplant patient did not require immediate intervention; two patients required pericardiocentesis alone, and six underwent pericardiocentesis and surgical intervention. All nine perforations were from the femoral venous approach (p CONCLUSIONS Risk of endomyocardial biopsy is highest in sick children with suspected myocarditis on inotropic support. However, EMB can be performed safely with very low morbidity in pediatric heart transplant recipients.
Denying What Workers Believe Are Unethical Workplace Requests: Do Workers Use Moral, Operational, or Policy Justifications Publicly?

This message-production experiment demonstrates workers’ tendency to use organizational policy justifications when publicly denying what they privately believe are unethical requests. Working adults (N = 234) responded to an unethical request from a supervisor, coworker, or subordinate. Participants avoided using explicitly moralized justifications for their noncompliance publicly and thus engaged in issue crafting. Specifically, content and statistical analyses revealed that (a) most participants invoked policy justifications to deny requests and (b) differences in hierarchical relationships were not significantly associated with policy justification frequency. These dynamics afford important face-saving functions but hold implications for the moral learning capacity of organizations. The essay concludes with implications for crafting organizational ethics policy.
Message and talker identification in older adults: effects of task, distinctiveness of the talkers' voices, and meaningfulness of the competing message.

Purpose In this study, the authors investigated (a) the effects of task, vocal distinctiveness of the competing talkers, and meaningfulness of the competitor on older listeners' identification of a...
Histologic features predict local recurrence after breast conserving therapy of phyllodes tumors.

Background: Pathologists can distinguish benign phyllodes tumors, which very rarely metastasize, from malignant phyllodes tumors, which metastasize in approximately one fourth of patients. However, whether these same histologic criteria can be used to predict the likelihood that a phyllodes tumor will locally recur after breast conserving therapy remains controversial.
The Logic of Belief and Belief Change: A Decision Theoretic Approach

Savage [L. Savage, ‘‘The Foundations of Statistics,’’ Wiley, New York, 1954] showed how properties of a decision maker’s probabilistic beliefs can be deduced from primitive consistency axioms on preferences. This paper extends that approach and shows how logical properties of beliefwhich underlie economists’ models of information and knowledgecan be related to properties of preferences. Journal of
Lower bounds for the Hausdorff dimension of n-dimensional self-affine sets

Abstract It was shown by Falconer [K. J. Falconer, The Hausdorff dimension of self-affine fractals, Math. Proc. Comb. Phil. Soc. 103, 339–350 (1988)] that there is an upper estimate for the Hausdorff dimension of a self-affine set embedded in R n. This paper finds a corresponding lower bound for the Hausdorff dimension. We then show an example where the two bounds are very close.
Lead alters parathyroid hormone‐related peptide and transforming growth factor‐β1 effects and AP‐1 and NF‐κKB signaling in chondrocytes

The skeletal system is an important target for lead toxicity. One of the impacts of lead in the skeleton, the inhibition of axial bone development, is likely due to its effect on the normal progression of chondrocyte maturation that is central to the process of endochondral ossification. Since little is known about the effect of lead on chondrocyte function/maturation, its impact on (1) growth factor-induced proliferation, (2) expression of maturation-specific markers type X collagen and BMP-6, and (3) the activity of AP-1 and NF-kappaB was examined in chick growth plate and sternal chondrocyte models. Exposure to lead alone (1-30 microM) resulted in a dose-dependent inhibition of thymidine incorporation in growth plate chondrocytes. Lead also blunted the stimulation of thymidine incorporation by parathyroid hormone-related peptide (PTHrP) and transforming growth factor-beta1 (TGF-beta1), two critical regulators of chondrocyte maturation. Lead (1 and 10 microM), TGF-beta1 (3 ng/ml) and PTHrP (10(-7) M) all significantly inhibited the expression of type X collagen, a marker of chondrocyte terminal differentiation. However, when in combination, lead completely reversed the inhibition of type X collagen by PTHrP and TGF-beta1. The effect of lead on BMP-6. an inducer of terminal differentiation. was also examined. Independently, lead and TGF-beta1 were without effect on BMP-6 expression, but PTHrP significantly suppressed it. Comparatively, lead did not alter PTHrP-mediated suppression of BMP-6, but in combination with TGF-beta1. BMP-6 expression was increased 3-fold. To determine if lead effects on signaling might play a role in facilitating these events, the impact of lead on NF-kappaB and AP-1 signaling was assessed using luciferase reporter constructs in sternal chondrocytes. Lead had no effect on the AP-1 reporter, but it dose-dependently inhibited the NF-kappaB reporter. PTHrP, which signals through AP-1, did not activate the NF-kappaB reporter and did not affect inhibition of this reporter by lead. In contrast, PTHrP activation of the AP-1 reporter was dose-dependently enhanced by lead. These findings, which establish that chondrocytes are important targets for lead toxicity, suggest that the effects of lead on bone growth are derived from its impact on the modulation of chondrocyte maturation by growth factors and second messenger signaling responses.
An efficient supersonic wind tunnel drive system for Mach 2.5 flows

A novel efficient drive system has been developed which provides for the continuous operation of a pitot Mach 2.5 wind tunnel at compression ratios down to 0.625:1. The drive system does not require an overpressure to start, and no hysteresis has been observed. The general design of the proof-of-concept wind tunnel using the new drive system and its modifications are described.
Thermal and Flow Performance of a Microconvective Heat Sink With Three-Dimensional Constructal Channel Configuration

The design, performance, manufacturing, and experimental validation of two convective heat sinks with scalable dimensions are presented. The heat sinks consist of an array of elemental units arranged in parallel. Each elemental unit is designed as a network of branching channels whose dimensions follow a group of geometric relations that have been derived from physiological fluid transport systems and the constructal method. The goal of these relations is to optimize both the point-to-point temperature difference within the heat sink and the pressure drop across the device under imposed geometric constraints. The first branching network is a generic three-dimensional (3-D) structure that was analyzed to push the limit of the heat sinks capability. The second is a heat sink that was designed specifically with the tape-casting fabrication method in mind. The heat sink has a branching network embedded within low temperature cofire ceramic (LTCC) and the same network embedded within thick film silver, which has the ability of being cofired with low temperature cofired ceramic substrates. The performance is evaluated using both a channel-level lumped model and a CFD model. The performance for different heat sink materials (low-temperature cofired ceramic and silver) is presented. The key results are then compared with the experimental results of the two scaled models. The results show good agreement within the experimental uncertainty. This validation confirms that the thermal performance and pumping efficiency of the constructal heat sink is superior compared to porous metal and conventional microchannel heat sinks under the same operating conditions, and that the designs are only limited by manufacturing techniques.
Role of calcium‐activated potassium channels in transmitter release at the squid giant synapse.

1. Several compounds known to block Ca2+-activated K+ channels were microinjected into squid 'giant' presynaptic terminals to test the hypothesis that these channels mediate Ca2+-dependent neurotransmitter release. 2. Injection of tetrapentylammonium, nonyl-triethylammonium and decamethonium all reversibly blocked transmission evoked by presynaptic action potentials. 3. All three of these compounds blocked presynaptic Ca2+ channels. The actions of tetrapentylammonium on presynaptic Ca2+ influx were examined in detail and found to be quantitatively sufficient to account for the ability of this compound to inhibit transmitter release. 4. Injection of Ba2+, another agent known to block Ca2+-activated K+ channels, also reversibly blocked evoked transmitter release. Ba2+ simultaneously enhanced basal (asynchronous) transmitter release and thus may be decreasing evoked release by depleting transmitter quanta available for release. 5. None of these results provide any support for the hypothesis that Ca2+-activated K+ channels mediate Ca2+-dependent release of transmitter at the squid synapse. However, our results have identified a new class of compounds that block Ca2+ channels from their cytoplasmic surface.
Ceria‐Electrolyte‐Based Mixed Potential Sensors for the Detection of Hydrocarbons and Carbon Monoxide

Mixed potential sensors based on zirconia electrolytes have been extensively investigated for the detection of and hydrocarbons in oxygen‐containing streams. In this paper, the response of a sensor operating at is reported for the first time and is compared to that of a zirconia sensor. The response of the ceria‐electrolyte sensor was more stable and reproducible than that of the zirconia‐electrolyte sensor. This difference in response has been attributed to an improvement in the oxygen reduction kinetics of the gold electrode on the ceria electrolyte. ©1999 The Electrochemical Society
Perturbative resummed series for top quark production in hadron reactions.

Our calculation of the total cross section for inclusive production of {ital t{bar t}} pairs in hadron collisions is presented. The principal ingredient of the calculation is resummation of the universal leading-logarithm effects of gluon radiation to all orders in the quantum chromodynamics coupling strength, restricted to the region of phase space that is demonstrably perturbative. We derive the perturbative regime of the resummed series, starting from the principal-value resummation approach, and we isolate the perturbative domain in both moment space and, upon inversion of the corresponding Mellin transform, in momentum space. We show that our perturbative result does not depend on the manner nonperturbative or infrared effects are handled in principal-value resummation. We treat both the quark-antiquark and gluon-gluon production channels consistently in the MS factorization scheme. We compare our method and results with other resummation methods that rely on the choice of infrared cutoffs. We derive the renormalization or factorization scale dependence of our re- summed cross section, and we discuss factorization scheme dependence and remaining theoretical uncertainties, including estimates of possible nonperturbative contributions. We include the full content of the exact next-to-leading order calculation in obtaining our final results. We present predictions of the physical cross sectionmore » as a function of top quark mass in proton-antiproton reactions at center-of-mass energies of 1.8 and 2.0 TeV. We also provide the differential cross section as a function of the parton-parton subenergy. {copyright} {ital 1996 The American Physical Society.}« less
Validation of patient headache care education system (PHCES) using a software reuse reference model

The research goal in our study of educational medical information systems tools is to improve the performance of patient decision making by integrating medical professional information with computer-augmented information and to benefit patients for short and long periods of time. In part, this goal may be reached by cost-effective software development with validated reusable Patient Care Education Systems object design models, user interface, object-oriented approach for product line and with the help of a valid Patient Headache Care Education System (PHCES) derived from these models.
Corrosion and Erosion Behavior in Supercritical CO2 Power Cycles

Supercritical Carbon Dioxide (S-CO2) is emerging as a potential working fluid in power-production Brayton cycles. As a result, concerns have been raised regarding fluid purity within the power cycle loops. Additionally, investigations into the longevity of the S-CO2 power cycle materials are being conducted to quantify the advantages of using S-CO2 versus other fluids, since S-CO2 promises substantially higher efficiencies. One potential issue with S-CO2 systems is intergranular corrosion [1]. At this time, Sandia National Laboratories (SNL) is establishing a materials baseline through the analysis of 1) “as received” stainless steel piping, and 2) piping exposed to S-CO2 under typical operating conditions with SNL’s Brayton systems. Results from ongoing investigations are presented.A second issue that SNL has discovered involves substantial erosion in the turbine blade and inlet nozzle. It is believed that this is caused by small particulates that originate from different materials around the loop that are entrained by the S-CO2 to the nozzle, where they impact the inlet nozzle vanes, causing erosion. We believe that, in some way, this is linked to the purity of the S-CO2, the corrosion contaminants, and the metal particulates that are present in the loop and its components.Copyright © 2014 by ASME
The Role of Temporal Sequence Learning in Guiding Visual Attention Allocation

Models of visual attention allocation suggest that monitoring is driven primarily by proximal cues like bandwidth and value. However, these cues might not always be predictive of the meaningful events an operator is asked to monitor. The aim of the current study is to extend visual sampling models by studying whether sampling can be influenced by more distal cues, like detecting patterns in the monitored signal, when proximal cues, like bandwidth, are not predictive of the meaningful events the operator is asked to monitor. Ten participants completed a task based on Senders’ (1964) experiment where operators were asked to monitor a series of four gauges to detect when the gauges traveled into the alarm region. The performance results suggest that participants could successfully adapt to the temporal sequence. However, participants did not show explicit awareness of the sequence, indicating that this type of learning could, in some cases, be implicit. Implications for display design and training are discussed.
Planters and Politics in Peru, 1895-1919

Research for this article was funded by a Ford Foundation Fellowship in 1974-5 and by a Fulbright Fellowship in autumn 1987.
CHARACTERIZATION OF MESA VERDE BLACK-ON-WHITE CERAMICS FROM SOUTHWESTERN COLORADO USING NAA

Sixty Mesa Verde variety Black-on-white bowls from Castle Rock Pueblo (5MT1825) and Sand Canyon Pueblo (5MT765) in southwestern Colorado were chemically characterized using neutron activation analysis. Eleven clay sources local to the sites in the McElmo Drainage area were also analyzed. The results revealed two distinct compositional groups containing relative frequencies that imply local production. The occurrence of trade between the two sites was also identified.
Probes of universal extra dimensions at colliders

In the Universal Extra Dimensions model of Appelquist, Cheng and Dobrescu, all of the Standard Model fields are placed in the bulk and thus have Kaluza-Klein (KK) excitations. These KK states can only be pair produced at colliders due to the tree-level conservation of KK number, with the lightest of them being stable and possibly having a mass as low as {approx_equal} 350 400 GeV. After calculating the contribution to g-2 in this model we investigate the production cross sections and signatures for these particles at both hadron and lepton colliders. We demonstrate that these signatures critically depend upon whether the lightest KK states remain stable or are allowed to decay by any of a number of new physics mechanisms. These mechanisms which induce KK decays are studied in detail.
HcpR of Porphyromonas gingivalis Is Required for Growth under Nitrosative Stress and Survival within Host Cells

Although the Gram-negative, anaerobic periodontopathogen Porphyromonas gingivalis must withstand nitrosative stress, which is particularly high in the oral cavity, the mechanisms allowing for protection against such stress are not known in this organism. In this study, microarray analysis of P. gingivalis transcriptional response to nitrite and nitric oxide showed drastic upregulation of the PG0893 gene coding for hybrid cluster protein (Hcp), which is a putative hydroxylamine reductase. Although regulation of hcp has been shown to be OxyR dependent in Escherichia coli, here we show that in P. gingivalis its expression is dependent on the Fnr-like regulator designated HcpR. Growth of the isogenic mutant V2807, containing an ermF-ermAM insertion within the hcpR (PG1053) gene, was significantly reduced in the presence of nitrite (P < 0.002) and nitric oxide-generating nitrosoglutathione (GSNO) (P < 0.001), compared to that of the wild-type W83 strain. Furthermore, the upregulation of PG0893 (hcp) was abrogated in V2807 exposed to nitrosative stress. In addition, recombinant HcpR bound DNA containing the hcp promoter sequence, and the binding was hemin dependent. Finally, V2807 was not able to survive with host cells, demonstrating that HcpR plays an important role in P. gingivalis virulence. This work gives insight into the molecular mechanisms of protection against nitrosative stress in P. gingivalis and shows that the regulatory mechanisms differ from those in E. coli.
Neonatal mortality in the developing world.

This paper examines age patterns and trends of early and late neonatal mortality in developing countries using birth history data from the Demographic and Health Surveys (DHS). Data quality was assessed both by examination of internal consistency and by comparison with historic age patterns of neonatal mortality from England and Wales. The median neonatal mortality rate (NMR) across 108 nationally-representative surveys was 33 per 1000 live births. NMR averaged an annual decline of 1.9 % in the 1980s and 1990s. Declines have been faster for late than for early neonatal mortality and slower in Sub-Saharan Africa than in other regions. Age patterns of neonatal mortality were comparable with those of historical data indicating no significant underreporting of early neonatal deaths in DHS birth histories. (authors)
Adolescent Sexual Assault: Prevalence, Risk Associates, Outcomes, and Intervention

Adolescence and young adulthood is a notable period of risk for sexual assault, with more than half of all rape victims experience their first rape before the age of 18. Whereas many who experience this form of violence exhibit marked resilience, adolescent sexual assault is notably associated with negative mental and physical health outcomes that may include but are not limited to depression, post-traumatic stress, sexually transmitted infections, and substance misuse. This chapter is intended to provide a brief overview of the literature regarding adolescent sexual assault, including an introduction to terminology commonly used in legal, clinical, and scientific discourse, as well as discussion of the scope of the problem of sexual assault among adolescents, a review of factors potentiating risk for sexual assault, associated physical and mental health outcomes, and a brief introduction to evidence-supported intervention and treatment relevant to sexual assault.
Reduced state fair queuing for edge and core routers

Despite many years of research, fair queuing still faces a number of implementation challenges in high speed routers. In particular, in spite of proposals such as DiffServ, the state needs for even simple schedulers are still large for heavily channelized core routers and for edge routers. An earlier proposal, Stochastic Fair Queuing, reduces state but at the expense of added unfairness between certain flows. Another earlier scheme, Core Stateless Fair Queuing, requires header changes and does not address the state needs of edge routers. By contrast, our paper proposes a randomization technique that removes the need to store deficit counters per flow in Deficit Round Robin and its variants. Even without the counters, we show, using both analysis and simulation, that randomized technique preserves throughput fairness properties of DRR. This randomization technique introduced in this paper can be used to considerably reduce the state requirements of high speed schedulers in edge and core routers, making hardware designs feasible. The randomization idea in this paper can also be applied to other round robin schedulers as well as potentially in entirely different scenarios wherever deficits need to be tracked over time explicitly.