cssi/SciSciGPT-SciSciNet huggingface dataset:
Ultrasonic Guided Waves for Lap Splice Joint Inspection in Aging Aircraft

The integrity and reliability of adhesive joints in structural applications has long been a critical issue. Failure of these bonds during service could be catastrophic. In particular, the aviation industry due to its progressively aging fleet calls for a reliable non-destructive testing technique to characterize the bond quality. Several NDE techniques were developed each with its own advantages and disadvantages. [1–2] Utilization of ultrasonic guided waves offer a reliable and time efficient method. [3] Following several laboratory studies this technique was tested on a service damaged aircraft at Sandia National Laboratories in Albuquerque, NM. A Double Spring Hopping Probe (DSHP) was developed and tested on this test bed. A protocol for the inspection of lap splices and tear strap was established. The concepts of utilization of wave structure in mode selection, angle and frequency tuning for optimal use of the Lamb type guided waves are addressed. Highlights of our recent work on aging aircraft inspection are presented in this paper. The work expands on our earlier presentations. [4]
Radiation Damage Studies on Natural and Synthetic Rock Salt for Waste Disposal Applications

Natural rock salt and synthetic NaCl develop negative ion defects (F centers) when irradiated between 20 and 300C. Both form high concentrations of sodium metal colloid particles when irradiated in the 125 to 200C region. Based on the current data, it is estimated that the exposures expected from high-level waste disposal canister will cause 0.01 to 0.1 mole percent of the sodium in the surrounding rock salt to be converted to sodium metal colloid particles. Defect formation is dependent on temperature, crystal strain, dose, dose rate, origin of crystals and possibly other factors.
Molecular Basis of Biofilm Development by Pseudomonads

Many of the tools for studying biofilms were developed in pseudomonads and, as such, these organisms have become a key model system for biofilm development by gram-negative bacteria. This chapter discusses what is known about biofilm development in pseudomonads and present working models of biofilm formation by these organisms. Cells are released from mature biofilms and reenter the planktonic state, making biofilm development a cyclic pathway in pseudomonads. Inorganic phosphate may be a key environmental factor required for biofilm formation by pseudomonads. Pseudomonas fluorescens and P. putida mutants lacking flagella have colonization defects on biotic surfaces, such as plant seeds and roots, and abiotic surfaces, such as sand, soil, plastic, and silicone. In P. aeruginosa, a complex between the virulence factor regulator (Vfr) and cAMP will form under glucose-limiting conditions. The study of the mechanisms of biofilm maintenance will likely be a fruitful area of investigation in the coming years. The chapter reviews what little is known about maintaining mature biofilm structure. A biofilm acts as reservoir for bacterial expansion in which successful colonization in one location subsequently permits surface exploration of numerous regions. The chapter discusses what is known about the biology of bacterial detachment. Insight into the biology of detachment will be a useful tool in the design of therapeutic agents for the fight against biofilm-based infections and for the disinfection of surfaces found in clinical and industrial settings.
On averaged and normal form equations

The method of ayeraging has long been an important method for the analysis of nonlinear systems. One method using normal forms has more recently become a tool in applied mathematics. Both methods convert systems of ordinary differential equations to simpler equations by using a sequence of change of variables. This study can be interpreted as a local analysis in that it treats equations that are nonlinear perturbations of linear equations. We show that the two methods are essentially equivalent.
Interactions between surface hydroxyls and adsorbed molecules

Abstract Gravimetric and infrared spectroscopic measurements were made of cyclohexane and cyclohexane- d 12 adsorbed on silica. The adsorptions were reversible and weak, and were generally like those expected for the adsorption of an inactive adsorbate on a hydroxylated surface. However, the infrared spectra of the adsorbed cyclohexane (and to a lesser extent, of cyclohexane- d 12 ) were perturbed to a much greater extent than is normally encountered for weak adsorption. The effects were attributed to Raman bands becoming infrared active because the adsorbed molecules, being confined to the chair form, were in an unusually asymmetric environment on the surface.
A coordination perspective on software architecture: towards a design handbook for integrating software components

This thesis argues that many of the difficulties associated with building software applications by integrating existing components are related to a failure of current programming languages to recognize component interconnection as a separate design problem, orthogonal to the specification and implementation of a component's core function. It proposes SYNOPSIS, an architectural description language which supports two orthogonal abstractions: activities, for representing the functional pieces of an application, and dependencies, for describing their interconnection relationships. Coordination processes, defined as an attribute of dependencies, describe implementations of interconnection protocols. Executable systems can be generated from SYNOPSIS descriptions by successively replacing activities with more specialized versions and managing dependencies with coordination processes, until all elements of the description are specific enough for code generation to take place. Furthermore, it proposes a "design handbook", consisting of a vocabulary of common dependency types and a design space of associated coordination processes. The handbook is based on the insight that many software interconnection relationships can be described using a relatively narrow set of concepts orthogonal to the problem domain of most applications, such as resource flows, resource sharing, and timing dependencies. A prototype component-based application development tool called SYNTHESIS was developed. SYNTHESIS maintains a repository of increasingly specialized dependency types, based on the proposed design handbook. It assists the generation of executable applications by successive semi-automatic transformations of their SYNOPSIS descriptions. A set of four experiments is described. Each experiment consisted in specifying a test application as a SYNOPSIS diagram, associating application activities with components exhibiting various mismatches, and using SYNTHESIS to assemble these components into executable systems. SYNTHESIS was able to exploit its dependencies repository in order to resolve a wide range of interoperability and architectural mismatches and integrate independently developed components into the test applications, with minimal or no need for additional manually-written code. It was able to reuse a single SYNOPSIS architectural description in order to generate versions of a test application for two different execution environments. Finally, it was able to suggest various alternative architectures for integrating each component set into its corresponding application.
Prediction of Heat Exchanger — Heat Transfer Coefficient Decay Due to Fouling

The reduction over time of the overall heat transfer coefficient in Bayer Process tubular heaters due to DSP fouling is discussed. A mathematical heat transfer model of this problem has been developed. The model is in a general form allowing for the use of different kinetic equations for the DSP formation reaction. Liquor-side heat transfer coefficients are calculated from correlations using the liquor physical properties. Steam-side heat transfer coefficients are calculated using a Nusselt-type equation. The heat transfer model predictions are compared to experimental results.
CASSCF and CASPT2 calculations on the cleavage and ring inversion of bicyclo[2.2.0]hexane find that these reactions involve formation of a common twist-boat diradical intermediate.

(6/6)CASSCF and CASPT2/6-31G* calculations have been performed to understand the experimental finding of Goldstein and Benzon (J. Am. Chem. Soc. 1972, 94, 5119) that exo-bicyclo[2.2.0]hexane-d4 (1b...
Design and performance characterization strategy using modeling for biofiltration control of odorous hydrogen sulfide

Abstract Biofilter, dynamic modeling software characterizing contaminant removal via biofiltration, was used in the preliminary design of a biofilter to treat odorous hydrogen sulfide (H2S). Steady-state model simulations were run to generate performance plots for various influent concentrations, loadings, residence times, media sizes, and temperatures. Although elimination capacity and removal efficiency frequently are used to characterize biofilter performance, effluent concentration can be used to characterize performance when treating to a target effluent concentration. Model simulations illustrate that, at a given temperature, a biofilter cannot reduce H2S emissions below a minimum value, no matter how large the biofilter or how long the residence time. However, a higher biofilter temperature results in lower effluent H2S concentrations. Because dynamic model simulations show that shock loading can significantly increase the effluent concentration above values predicted by the steady-state model simu...
Modeling residence time with a three-dimensional hydrodynamic model: Linkage with chlorophyll a in a subtropical estuary

Abstract Residence time calculated with a three-dimensional hydrodynamic model was analyzed together with field measurements of chlorophyll a collected through long-term monitoring programs and synoptic-scale water quality mapping in the Caloosahatchee Estuary located in Florida, USA. Freshwater inflows to the estuary are highly managed at the head water control structure. A total of 14 freshwater inflow rates ranging from 0 to 283 m 3 s −1 were simulated to represent the whole spectrum of hydrologic and water management conditions. Residence time, reported as the e-folding time, ranged from a few days to more than 60 days, depending on the magnitude of freshwater discharge and location in the estuary. The spatial heterogeneity of residence time indicated that there existed a zone in the estuary where water parcels reside for a longer period of time than in other areas of the estuary. The location of this “residence time maximum” zone progressed further toward the mouth of the estuary with increasing freshwater discharge. The location of peak chlorophyll a concentration along the longitudinal axis of the estuary as measured through long-term monitoring and synoptic water quality mapping, also fluctuated with freshwater discharge and coincided with the zone of maximum residence time. The results confirmed the fundamental role of freshwater inflow in the control of residence time and accumulation of phytoplankton biomass. The study helps elucidate how and where phytoplankton respond to freshwater inflows at the head of the estuary.
Expression of type 1 plasminogen activator inhibitor in chronic pulmonary thromboemboli.

BACKGROUNDChronic thromboembolic pulmonary hypertension is the result of nonresolving pulmonary emboli that lead to chronic obstruction of the central pulmonary arteries.METHODS AND RESULTSTo determine if the failure to lyse pulmonary thromboemboli is caused by the local expression of the primary inhibitor of tissue-type plasminogen activator (type 1 plasminogen activator inhibitor, PAI-1), levels of PAI-1 antigen and mRNA were analyzed by immunohistochemistry and in situ hybridization in specimens harvested from a series of patients during pulmonary thromboendarterectomies. Red, fibrin-rich thrombi within the thromboendarterectomy specimens were lined with a single layer of endothelial cells exhibiting high levels of PAI-1 antigen. Quantitation of the in situ hybridization signal revealed that a significant increase in PAI-1 mRNA was present in the endothelial cells lining the fresh thrombi in comparison to the signal present in the endothelial cells from noninvolved areas of patients' pulmonary arteries...
Analytical and Experimental Investigations of Laminar Mixing of Confined Heterogeneous Jets

Recirculating cells and entrance conditions influence on confined heterogeneous jets laminar mixing, measuring velocity and concentration profiles
Hemocyanin of the chambered Nautilus: Structure-function relationships

Abstract The chambered nautilus, Nautilus pompilius, is a cephalopod mollusc that lives in deep water in the western Pacific. Structural and functional studies were undertaken on the high-molecular-weight copper protein that it uses as an oxygen carrier. Nautilus hemocyanin was found to resemble that of another cephalopod, the squid Loligo paelii. Unlike the hemocyanin of the gastropod molluscs, neither Nautilus nor Loligo hemocyanin exists in aggregation states with sedimentation coefficients of 100 S. The highest aggregation state in these two hemocyanins has a sedimentation coefficient of 58 S. This is significantly lower than the 64–66 S values found for half-dissociated molecules of typical gastropod hemocyanins. The dissociation of Nautilus hemocyanin was found to be sensitive to pH and divalent cations such as calcium and magnesium. At high pH, and in the absence of divalent cations, subunits that are believed to be large single polypeptide chains are found. They have sedimentation coefficients of 11 S, similar to subunit sedimentation behavior throughout the mollusc hemocyanin line. Unlike squid hemocyanin, Nautilus hemocyanin shows no intermediate dissociation products. Undissociated Nautilus hemocyanin shows a moderate oxygen affinity ( log P 1 2 = 0.8 at pH 8 ), a small Bohr effect ( log P 1 2 = 0.97 at pH 7.0 ), and a fairly low degree of cooperativity in oxygen binding ( n 1 2 = 1.5–2.0 ). Dissociation of Nautilus hemocyanin by dialysis against EDTA at high pH yields material of higher affinity, no cooperativity, and very slight pH sensitivity. The difference between the oxygen affinity of whole and dissociated Nautilus hemocyanin is most pronounced at low degrees of oxygen saturation. The question of possible subunit heterogeneity in Nautilus hemocyanin was addressed. Dissociated Nautilus hemocyanin was chromatographed at high pH in the absence of divalent cations. Three distinct peaks were found. These chromatographic zones, representing putative polypeptide chains of Nautilus hemocyanin, show significant differences in their oxygen binding characteristics. The presence of structurally and functionally diverse subunits in this cephalopod hemocyanin is reminiscent of that observed for two gastropod hemocyanins, and is thus suggestive that subunit heterogeneity may be a more general feature in the molluscan hemocyanins than previously appreciated.
Refractive states of eyes and association between ametropia and breed in dogs.

Objective To assess the refractive state of eyes in various breeds of dogs to identify breeds susceptible to ametropias. Animals 1,440 dogs representing 90 breeds. Procedures In each dog, 1 drop of 1% cyclopentolate or 1% tropicamide was applied to each eye, and a Canine Eye Registration Foundation examination was performed. Approximately 30 minutes after drops were administered, the refractive state of each eye was assessed via streak retinoscopy. Dogs were considered ametropic (myopic or hyperopic) when the mean refractive state (the resting focus of the eye at rest relative to visual infinity) exceeded +/- 0.5 diopter (D). Anisometropia was diagnosed when the refractive error of each eye in a pair differed by > 1 D. Results Mean +/- SD refractive state of all eyes examined was -0.05 +/- 1.36 D (emmetropia). Breeds in which the mean refractive state was myopic ( or = +0.5 D) included Australian Shepherd, Alaskan Malamute, and Bouvier des Flandres. Astigmatism was detected in 1% (14/1,440) of adult (> or = 1 year of age) dogs; prevalence of astigmatism among German Shepherd Dogs was 3.3% (3/90). Anisometropia was detected in 6% (87/1,440) of all dogs and in 8.9% (8/90) of German Shepherd Dogs. Conclusions and clinical relevance Refractive states of canine eyes varied widely and were influenced by breed and age. In dogs expected to have high visual function (eg, performance dogs), determination of refractive state is recommended prior to intensive training.
A study of contact stresses in pin-loaded orthotropic plates

Abstract A mixed finite element scheme with a dynamic as well as a static coefficient of friction is used in the evaluation of contact stresses in pin-loaded plates. The case of pin-loaded aluminum plate is studied to obtain better correlation with experimental results, and a pin-loaded orthotropic plate behavior as predicted by an analytical solution is compared with the present predictions. A hybrid (experimental/ numerical) technique is used to estimate the static and dynamic coefficients of friction of the aluminum pin/plate system. An elastic-plastic analysis based failure model of pin-loaded laminates is also presented and illustrated by examples which indicate when bearing, shearout and tensile failure occur in the laminate mechanical joints.
Nanorough gold for enhanced Raman scattering

Conventional Raman scattering is a workhorse technique for detecting and identifying complex molecular samples. In surface enhanced Raman scattering, a nanorough metallic surface close to the sample enhances the Raman signal enormously. In this work, the surface is on a clear epoxy substrate. The epoxy is cast on a silicon wafer, using 20 nm of gold as a mold release. This single step process already produces useful enhanced Raman signals. However, the Raman signal is further enhanced by (1) depositing additional gold on the epoxy substrate and (2) by using a combination of wet and dry etches to roughen the silicon substrate before casting the epoxy. The advantage of a clear substrate is that the Raman signal may be obtained by passing light through the substrate, with opaque samples simply placed against the surface. Results were obtained with solutions of Rhodamine 6G in deionized water over a range of concentrations from 1 nM to 1 mM. In all cases, the signal to noise ratio was greater than 10:1.
Delivering real-time satellite data to a broader audience

This paper presents our work of enhancing the existing cyberinfrastructure using Web 2.0 technologies for delivering real time satellite data to a broader audience. As a resource provider on the TeraGrid, Purdue University hosts several data collections for earth and environmental research, including a large number of satellite data products that are received and generated in real time at the Purdue Terrestrial Observatory (PTO). A science gateway portal, named PRESTIGE, has been developed as the access point to services related to the satellite data generated at PTO. It remains a major challenge to help potential users easily discover the data products that are available and access them based on their needs. In an effort to address this challenge, we developed different interfaces for different user groups. We use the Google gadget as a new way to deliver satellite data and information to a broad user community. Three satellite data viewer gadgets have been developed and deployed. They connect to a data generation and processing system at the backend. The gadgets embrace the recent Web 2.0 technologies in bringing the rich access and sharing capabilities available in the general cyberspace to the scientific user communities.
High-voltage testing techniques

NUMEROUS TECHNIQUES for use in acceptance testing of apparatus have been developed over the past 25 years. It is not possible to cover, because of lack of space, the various devices that may be used in high-voltage laboratories for development work, except in a very general way. At the end of this article, a list of papers most easily accessible to American readers is included. In addition, rather comprehensive bibliographies are available.1–3 There have been many investigators who have made important contributions but are not mentioned because of the necessity for keeping references to a reasonable length.
Microfabricated V-band left-handed transmission lines

Abstract We present the design, microfabrication, and characterization of V-band transmission lines, having a wide left-handed passband between 42 and 73 GHz. The mushroom structure and associated microfabrication method is further extended to build a 1-D left-handed transmission line working at 100 GHz and a 2-D left-handed structure with 9 × 9 cells, enabling 2-D or even 3-D left-handed metamaterials at high frequencies.
Construction of coordination-driven self-assembled [5 + 5] pentagons using metal-carbonyl dipyridine ligands.

The coordination-driven self-assembly of two metal−carbonyl-cluster-coordinated dipyridyl donors, (4-C5H4N)2C≡CCo2(CO)6 (1) and (4-C5H4N)2C≡CMo2Cp2(CO)4 (2), with a linear diplatinum(II) acceptor ligand was investigated. The structures of the resulting self-assembled polygons were found to be controlled by the steric bulk of the metal−carbonyl cluster adduct. The use of a sterically less imposing ligand 1 resulted in a pentagon−hexagon mixture, which was characterized by electrospray ionization time-of-flight mass spectroscopy. The exclusive formation of a [5 + 5] pentagon was achieved by the self-assembly of the bulkier molybdenum donor ligand 2 with a linear organoplatinum(II) acceptor ligand. Molecular force field modeling was used to study the structural details of the pentagonal and hexagonal architectures. The first Fe3−Co6−Pt6 trimetal [3 + 3] hexagon was also synthesized via the combination of 1 with a 120° ferrocenyldiplatinum(II) acceptor.
Water soluble phosphorus released by poultry litter: effect of extraction and time after application

The normally alkaline pH of poultry litter limits the solubility of P forms, especially the inorganic ones. Poultry litter acidification after field applications could result in increased P solubilization, so the use of water-soluble P (WSP) concentrations measured at the original litter pH might lead to an underestimation of the risk of P contamination of runoff water. In the laboratory, we studied the influence of pH (original and target pH 6 and 7) and shaking time (0.5, 1.0, 2.0, and 4.0 h) on the amounts of Total Dissolved P (TDP) and Molybdate Reactive P (MRP) extracted from two broiler and one breeder litters. Additionally we measured pH, MRP, and TDP evolution in the thatch and top 1 cm of soil during 115 days after application of broiler litter to a Bermudagrass pasture. Acidification of litter suspensions increased TDP by 34 to 72% and MRP by 24 to 69%. In the field, broiler litter pH decreased from 8.1 to 6.7 within 30 days after the application. The following evidence suggests that the WSP measured at the original litter pH might have been considerably less than that released in the field: (a) Based on adsorption isotherm data, the 97 μg P g–1 of soil applied as MRP would have been insufficient to result in an increased concentration of 16 μg P g–1 of soil as MRP; (b) The total increase in Dissolved Unreactive P (DUP) observed in soil (38 μg cm–2) was twice the amount measured in the litter at the original pH; and (c) The increase in MRP measured in soil 59 days after litter application could be linked to additional amounts of DUP not accounted for in the analysis at the original pH. These results highlight the importance of measuring WSP under conditions similar to those encountered by the litter after application.
Levetiracetam Effect in Demyelinating Ocular Flutter with Myoclonus

A 29-year-old male developed ocular flutter and subtle extremity myoclonus related to demyelination. Ocular flutter and myoclonus were symptomatically amenable to treatment with levetiracetam. Discontinuation of levetiracetam was associated with recurrent flutter and myoclonus over a two-year period of follow-up. Levetiracetam may be an effective agent for the symptomatic control of ocular flutter.
Design, synthesis and antiviral efficacy of a series of potent chloropyridyl ester-derived SARS-CoV 3CLpro inhibitors

Design, synthesis and biological evaluation of a series of 5-chloropyridine ester-derived severe acute respiratory syndrome-coronavirus chymotrypsin-like protease inhibitors is described. Position of the carboxylate functionality is critical to potency. Inhibitor 10 with a 5-chloropyridinyl ester at position 4 of the indole ring is the most potent inhibitor with a SARS-CoV 3CLpro IC50 value of 30 nM and an antiviral EC50 value of 6.9 μM. Molecular docking studies have provided possible binding modes of these inhibitors.
Baryon number violation and nonperturbative weak processes at Superconducting Super Collider energies

Baryon number violation and multiple production of {ital W} and Higgs bosons are described semiclassically in terms of the {ital instanton}--{ital anti}-{ital instanton} {ital valley}. We find (i) two saddle points, one describing {ital reflection} from a barrier and the other describing {ital tunneling} through it. We find (ii) a critical energy {ital E}{sub {ital c}}{similar to}35 TeV where the cross section is suppressed as exp({minus}const/{ital g}{sub {ital w}}{sup 2}), but the formulas are no longer valid; (iii) however, depending on the (still uncertain) Higgs bosson action, the cross section at this point may be large enough to be observable.
Analytical and experimental evaluations of the effect of broad property fuels on combustors for commercial aircraft gas turbine engines

Analytical and experimental studies were conducted in three contract activities funded by the National Aeronautics and Space Administration, Lewis Research Center, to assess the impacts of broad property fuels on the design, performance, durability, emissions and operational characteristics of current and advanced combustors for commercial aircraft gas turbine engines. The effect of fuel thermal stability on engine and airframe fuel system was evaluated. Trade-offs between fuel properties, exhaust emissions and combustor life were also investigated. Results indicate major impacts of broad property fuels on allowable metal temperatures in fuel manifolds and injector support, combustor cyclic durability and somewhat lesser impacts on starting characteristics, lightoff, emissions and smoke.
Ultrastructure of Presumed “Candidatus Rickettsia Andeanae” in Amblyomma maculatum (Acari: Ixodidae)

Amblyomma maculatum Koch, 1844 (also known as the Gulf Coast tick) is found in parts of the Americas, including the central and southern United States. Its primary importance is as the vector of Rickettsia parkeri, a spotted fever group rickettsia that causes an illness similar to, but milder than, Rocky Mountain spotted fever. A second spotted fever group rickettsia, "Candidatus Rickettsia andeanae," was detected in Gulf Coast ticks approximately 10 yr ago. However, the significance of this organism, including pathogenicity, has not yet been well-characterized. Here, we use transmission electron microscopy to describe bacteria within the tissues of A. maculatum ticks that were positive by polymerase chain reaction assay for "Ca. R. andeanae." In ultrathin sections of unfed A. maculatum adult females, we found evidence of bacteria with morphological features consistent with spotted fever group rickettsiae, including small size (≈0.3 by 0.9 μm), a halo zone (electron-lucent layer around the bacterium), and a trilaminar cell wall. In female ticks, bacteria were present in granular salivary glands and ducts, foregut, Malpighian tubules, nerve trunks, and reproductive tissue. These findings demonstrate evidence of "Ca. R. andeanae" in situ and contribute to our understanding of this novel rickettsia in A. maculatum.
Nodal and paranodal structural changes in mouse and rat optic nerve during Wallerian degeneration.

Abstract Ultrastructural changes in the nodal and paranodal regions of myelinated mouse and rat optic nerve fibers were followed between 4 h and 28 days during the course of Wallerian degeneration. In the mouse, axoplasmic changes, including accumulation of organelles and segregation of microtubules, were detectable 4 h after transection, and progressed to a maximum level on day 4, at which time many axons were markedly swollen. Dense axoplasm was seen as early as 16 h and was a common feature of degenerating axoplasm at later times. Paranodal changes, which first appeared as early as 16 h after injury, included detachment of terminal loops of myelin from the axolemma, disconnection of terminal loops from compact myelin lamellae and broadening of terminal loops, or separation of the loops from each other, resulting in paranodal elongation. In freeze-fracture replicas, the E-face of the axolemma showed the normal particle distribution as late as days 3–5. By day 8, however, the nodal particles were patchy and the overall nodal particle density was reduced to approximately half normal. Some normal-looking fibers were present at all stages examined, but their number had declined to about half the total population on day 5 and to less than 10% on day 11. In the rat, the overall sequence of events and time course were comparable to those in the mouse. Thus, the morphological changes found follow approximately the same sequence as that described previously in frog nerves, but progress more rapidly in the mouse and rat.
Mechanically induced intracellular calcium waves in osteoblasts demonstrate calcium fingerprints in bone cell mechanotransduction

An early response to mechanical stimulation of bone cells in vitro is an increase in intracellular calcium concentration ([Ca2+]i). This study analyzed the [Ca2+]i wave area, magnitude, duration, rise time, fall time, and time to onset in individual osteoblasts for two identical bouts of mechanical stimulation separated by a 30-min rest period. The area under the [Ca2+]i wave increased in the second loading bout compared to the first. This suggests that rest periods may potentiate mechanically induced intracellular calcium signals. Furthermore, many of the [Ca2+]i wave parameters were strongly, positively correlated between the two bouts of mechanical stimulation. For example, in individual primary osteoblasts, if a cell had a large [Ca2+]i wave area in the first bout it was likely to have a large [Ca2+]i wave area in the second bout (r2 = 0.933). These findings support the idea that individual bone cells have “calcium fingerprints” (i.e., a unique [Ca2+]i wave profile that is reproducible for repeated exposure to a given stimulus).
Structural changes during swelling of isolated rat mitochondria

Isolated rat liver and kidney mitochondria were swollen in hypotonie sucrose solutions and then examined in the electron microscope. The results were consistent with the hypothesis that unfolding of the cristae plays some part in swelling since cristae of swollen mitochondria appeared less abundant and with increased intercristal distances. The matrix became more electron-transparent. The fate of the outer membrane is uncertain.
Rapid desensitization induces internalization of antigen-specific IgE on mouse mast cells.

Background Rapid desensitization transiently prevents severe allergic reactions, allowing administration of life-saving therapies in previously sensitized patients. However, the mechanisms underlying successful rapid desensitization are not fully understood. Objectives We sought to investigate whether the mast cell (MC) is an important target of rapid desensitization in mice sensitized to exhibit IgE-dependent passive systemic anaphylaxis in vivo and to investigate the antigen specificity and underlying mechanisms of rapid desensitization in our mouse model. Methods C57BL/6 mice ( in vivo ) or primary isolated C57BL/6 mouse peritoneal mast cells (PMCs; in vitro ) were passively sensitized with antigen-specific anti–2,4-dinitrophenyl IgE, anti-ovalbumin IgE, or both. MCs were exposed over a short period of time to increasing amounts of antigen (2,4-dinitrophenyl–human serum albumin or ovalbumin) in the presence of extracellular calcium in vitro or by means of intravenous administration to sensitized mice in vivo before challenging the mice with or exposing the PMCs to optimal amounts of specific or irrelevant antigen. Results Rapidly exposing mice or PMCs to progressively increasing amounts of specific antigen inhibited the development of antigen-induced hypothermia in sensitized mice in vivo and inhibited antigen-induced PMC degranulation and prostaglandin D 2 synthesis in vitro . Such MC hyporesponsiveness was induced antigen-specifically and was associated with a significant reduction in antigen-specific IgE levels on MC surfaces. Conclusions Rapidly exposing MCs to progressively increasing amounts of antigen can both enhance the internalization of antigen-specific IgE on the MC surface and also desensitize these cells in an antigen-specific manner in vivo and in vitro .
Diplotypes of the Human Serotonin 1B Receptor Promoter Predict Growth Hormone Responses to Sumatriptan in Abstinent Alcohol-Dependent Men

Background Some studies have associated alcohol dependence (AD) with the human serotonin (5-HT) 1B receptor (HTR1B). This investigation explored the functional responsivity of HTR1B in abstinent AD men using a sumatriptan challenge, while measuring genetic heterogeneity in the HTR1B promoter. Methods Abstinent AD men ( n = 27) and abstinent men without any alcohol use disorder ( n = 19) were administered 6 mg of sumatriptan succinate, subcutaneously. Plasma samples collected over the following 2 hours were assayed for growth hormone (GH) concentrations. His DNA was genotyped for the A-161T and T-261G polymorphisms of the HTR1B promoter and diplotypes determined. Results Integrated GH responses were predicted by interactions of AD and promoter diplotypes, as well as subject ethnicity. The final model accounted for nearly 35% of the variance in GH responses. Post hoc evaluation revealed that AD was associated with a blunting of GH secretion only among individuals with the most common HTR1B diplotype (TT/TT). Conclusions A blunting of GH responses in abstinent AD men was observed only among those with the most common HTR1B promoter diplotype. Less common promoter diplotypes appeared protective. Controlling for genetic background is a useful augmentation of case-control pharmacological challenge strategies designed to elucidate the psychobiology of AD and other complex disorders.
Computer Modeling in Cardiac Electrophysiology

The skills of a computational physicist are shown to be useful in the seemingly distant field of cardiac electrophysiology. The propagation of cardiac action potentials and their ability to form spiral waves are easily understood at a basic level when standard concepts from the theory of partial differential equations are applied. The design of computer simulations of action potential propagation is facilitated by adapting numerical concepts routinely applied by computational physicists. These concepts must be modified and combined with computer structures standard in computer science to handle the timescale and spatial scale problems unique to the action potential propagation problem. The resulting simulation shows how details of ion channel dynamics determine properties of the spiral wave, including its propagation speed, its period, its stability, and the size of the spiral core.
Microscopic prediction of optical and electronic material properties in GaInNAs semiconductor lasers

A fit-parameter-free model is used to calculate optical and electronic material properties of GaInNAs semiconductor lasers. Incoherent processes which lead to dephasing of optical polarisations and carrier thermalisation are calculated microscopically by solving generalised quantum-Boltzmann equations for electron-electron and electron-phonon scattering. The theory is shown to give excellent quantitative agreement with experimental results. Shortcomings of simpler approaches are demonstrated. Carrier capture times in GaInNAs systems of varying well depth and width are calculated and the results are compared to those in InGaPAs- and AlInGaAs-based structures.
Lou Carnon-Deutsch, "Narratives of Desire: Nineteenth Century Spanish Fiction by Women"

(1995). Lou Charnon-Deutsch. Narratives of Desire: Nineteenth-Century Spanish Fiction by Women. Romance Quarterly: Vol. 42, No. 3, pp. 191-192.
Price Variability, Utility and Savings

The observation that an increase in the variation of the price of a commodity about its mean raises the expected consumer surplus generated by that commodity originates with Waugh (1944). Waugh and subsequent investigators (e.g. Massell (1969), Turnovsky (1976) and Bradford and Kelejian (1977)) use this result to derive propositions on the welfare and distributional effects of price stabilization schemes.' This approach ignores the uncertainty in real income generated by price variability. It also fails to consider the role of hedging against price variation through appropriate portfolio diversification. In this paper demand theory is used to show that relative price variability has an ambiguous effect on expected utility when only a single asset is available as a store of value. A positive effect is more likely when the demand elasticity is large relative to the degree of relative risk aversion and when the marginal propensity to consume the commodity in question is large. When there exists a futures market for each commodity, the consumer can hedge against price variation to insure a positive effect. Increased variance in a log-normally distributed price unambiguously raises expected utility when the consumer hedges optimally. A second purpose of this paper is to explore the implications of price variability for optimal savings as well as for expected utility. While the effects of uncertainty in the value of future endowments and assets on optimal savings have been explored extensively scant attention has been paid to the effects of relative price uncertainty.2 The present paper attempts to fill this gap for the case in which utility is intertemporally additively separable. Section 2 presents a general framework for analysing expected utility maximization in a two-period, multi-commodity, multi-asset environment in wh;-" prices and income in the second period are stochastic. Section 3 analyses the effect on expected utility of increased variability in the relative price of a single commodity in a two-commodity context. Here and in Section 5 the geometric mean preserving spread of Flemming, Turnovsky and Kemp (1977) provides a definition of increased variability. Section 4 derives optimal portfolio behaviour for the special case in which the relative price is log-normally distributed. The effect of price variability on optimal savings in a two-period context is considered in Section 5. Some concluding observations and an extension to a general equilibrium problem appear in Section 6.
Intermolecular interaction in some mixed polymer monolayers at the air water interface

Abstract The monolayer compression isotherms for six binary mixtures of polymethacrylates and poly (vinylacetate) at the air/water interface have been studied. The results are analyzed thermodynamically and indicate that, although most polymers are incompatible in the bulk, they may become compatible in the monolayer because of the spatial orientation of the atoms and groups.
Using live FRET imaging to reveal early protein–protein interactions during T cell activation: [Curr. Opin. Immunol. 16 (2004) 418]

The emerging challenge for proteomics in general and lymphocyte biology in particular is to understand protein–protein interactions in the dynamic context of the living cell. Particularly interesting are the molecular dynamics of the T cell receptor–CD3 complex and other immunoreceptors in immune synapses. Fluorescence (or Forster) resonance energy transfer (FRET) is one of the few techniques that are capable of giving dynamic information about the nanometer-range proximity between molecules, as opposed to simply the subcellular co-localization that is provided by fluorescence microscopy. Spectral changes in fluorescence intensity and down modulation of donor lifetime are the basis for rapidly developing approaches to real-time FRET imaging. With two-photon excitation, FRET can now be extended to in vivo imaging.
Voting in Initiative Elections: Does the Context of Racial and Ethnic Diversity Matter?

Does the racial and ethnic diversity of the area in which a voter lives affect his or her political behavior? Scholars have suggested a range of such effects, but these conclusions have questionable generalizability because the behavior they typically examine is racially charged. In this article, I test more general affects of racial and ethnic context by examining political behavior on a range of issues, both racially relevant and racially neutral. Specifically, I examine the impact of the racial and ethnic context on individual-level voting by whites in initiative elections. Merging 1996 and 1998 Voter News Service state exit poll survey data and United States Census Bureau contextual data, I find that there is a distinct relationship between racial and ethnic diversity and white voting behavior on racially relevant ballot initiatives, but that racial diversity does not have a consistent impact on voting on race-neutral initiatives.
Scheduling for heterogeneous processors in server systems

Applications on today's high-end systems typically make varying load demands over time. A single application may have many different phases during its lifetime, and workload mixes show interleaved phases. Memory-intensive work or phases may exhibit performance saturation at frequencies below the maximum possible for the processors due to the disparity between processor and memory speeds. Performance saturation is a sign of over-provisioning and leads to energy-inefficient systems. Computers using heterogeneous processors, with the same ISA, but different implementation details, have been proposed as a way of reducing power while avoiding or limiting performance degradation. However, using heterogeneous processors effectively is complicated and requires intelligent schedulingThe research reported here explores the use of a heterogeneous system of processors with identical ISAs and implementation details, but with differing voltages and frequencies. The scheduler uses the execution characteristics of each application to predict its future processing needs and then schedule it to a processor which matches those needs if one is available. The predictions are used to minimize the performance loss to the system as a whole rather than that of a single application. The result limits system power while minimizing total performance loss. A prototype implementation on a Power4 four-processor system is presented. The prototype scheduler is validated using both synthetic and real-world benchmarks. The prototype shows reasonable predictor accuracy and significant power savings for memory-bound applications
Axonal transport of selected particle-specific enzymes in rat sciatic nerve in vivo and its response to injury.

— Orthograde and retrograde axoplasmic transport of selected axonal organelles were examined by monitoring accumulation of enzyme activities residing in various types of particles proximal and distal to a ligature placed on rat sciatic nerve as a function of time after tying. Proximal to the tie, activity of acetylcholinesterase (AChE, EC 3.1.1.7; probably in small endoplasmic reticulum-like particles) accumulated for 2 days; then, during the next 5 days, the accumulation disappeared. Activities of glutamic dehydrogenase (GDH, EC 1.4.1.3) and monoamine oxidase (MAO, EC 1.4.3.4) (both located in mitochondria) accumulated steadily for 7 days. Accumulation of monoamine oxidase activity was more rapid than that of glutamic dehydrogenase during the first day or two. Acid phosphatase (acid P'tase, EC 3.1.3.2; in lysosomes) activity also accumulated throughout the week of observation. Accumulation of all four enzyme activities proximal to the ligature was blocked by nerve crush or subepineurial vinblastine injection 1 cm or more proximal to the site of the tie. Distal to the ligature, AChE activity accumulated early (14 h), and then gradually disappeared in the course of the week. MAO activity also accumulated, with a maximum at 2 days, and no further change thereafter. GDH activity, on the other hand, showed little accumulation during the first 2 days, but did appear in modest amounts at the end of the week. Distal accumulation of acid P'tase kept pace with proximal accumulation for the first day, and continued more slowly for another day, after which there was no further change. This system has been used to study the effects of axonal crush injury upon anterograde and retrograde axoplasmic transport. A tie applied at various times after injury, proximal to the site of injury, was used to show that orthograde transport of AChE was maintained for 1 day after tying, but at 2 days had fallen 50% or more, and within a week was down to 20–25% of control. At 3 days after injury retrograde transport of AChE activity was not different from the control. Orthograde transport of acid P'tase activity was depressed 35% by injury. Retrograde transport of acid P'tase was inhibited more than 50% both at 3 and at 7 days after injury. Transport of the mitochondrial enzymes was not measurably affected.
Psychology and Ecology

Abstract Psychologists are becoming increasingly interested in the environment and ecology. At the national level, I am familiar with many groups-both formal and informal-which focus on these topics. I am sure these efforts are duplicated in other countries and at the international level. Interest in and support of meetings such as this give testimony to the discipline's concerns. Indeed, journals and books with ecology or environment in their titles may soon, if they have not already, create a recognized subdiscipline of those names. The ecological movement is an interesting and important one, because not only is the environment being studied for its psychological interest, but also because those psychologists engaged in its investigation want to have an effect on the world. The y want the results of their studies to contribute to social policy and planning.
Analysis of volatile organic compounds from illicit cocaine samples

Detection of illicit cocaine hydrochloride shipments can be improved if there is a greater understanding of the identity and quantity of volatile compounds present. This study provides preliminary data concerning the volatile organic compounds detected in a limited set of cocaine hydrochloride samples. In all cases, cocaine was one of the major volatile compounds detected. Other tropeines were detected in almost all samples. Low concentrations of compounds which may be residues of processing solvents were observed in some samples. The equilibrium emissivity of cocaine from cocaine hydrochloride was investigated and a value of 83 parts-per-trillion was determined.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.