cssi/SciSciGPT-SciSciNet huggingface dataset:
PLATELET-DERIVED GROWTH FACTOR

Platelet-derived growth factor (PDGF) isoforms are polypeptide mediators that play a major role in stimulating the replication, survival, and migration of mesenchymal cells during the pathogenesis of fibrotic diseases. PDGF is secreted by a variety of cell types including epithelial cells, macrophages, and fibroblasts as a response to injury, and many proinflammatory cytokines mediate their mitogenic effects via the autocrine release of PDGF. PDGF-A and PDGF-B chain dimeric isoforms (PDGF-AA, PDGF-AB, and PDGF-BB) play important roles in the pathogenesis of fibrosis. These isoforms promote myofibroblast proliferation and chemotaxis, but also serve other functions including stimulation of collagen production and promotion of cell adhesion. Less is known regarding the significance of the more recently discovered PDGF-C and PDGF-D chain isoforms. The biological activity of PDGF is determined by the relative expression of PDGF α-receptors and β-receptors on the cell surface. These receptors are induced during lung fibrogenesis, thereby amplifying biological responses to PDGF isoforms. PDGF action is further modulated in the extracellular milleau by binding proteins, matrix molecules, and proteases.
The ABC Ontology and Model

This paper describes the latest version of the ABC metadata model. This model has been developed within the Harmony international digital library project to provide a common conceptual model to facilitate interoperability between metadata ontologies from different domains. This updated ABC model is the result of collaboration with the CIMI consortium whereby earlier versions of the ABC model were applied to metadata descriptions of complex objects provided by CIMI museums and libraries. The result is a metadata model with more logically grounded time and entity semantics. Based on this model we have been able to build a metadata repository of RDF descriptions and a search interface which is capable of more sophisticated queries than less-expressive, object-centric metadata models will allow.
Wheel thermal damage limits

A series of dynamometer tests were conducted to determine the limiting power required to produce wheel thermal damage, or the neutralization of the as-manufactured rim circumferential residual compressive stresses. Dynomometer and saw-cut tests were conducted on low-stress heat-treated CE-28, CH-36 and CB-38 freight car wheels to determine the onset of damage. The effects of various combinations of time and brake shoe power inputs, as well as the effects of rim thickness and the presence of the rail wheel, on the resistance of wheels to thermal damage were investigated. The test results showed that the amount of brake shoe thermal input required to thermally damage heat-treated low-stress wheels is far in excess of that of normal brake application. >
Phase setting and locomotion

The nematode Ascaris suum has been the object of intensive study by the group working under the direction of Antony Stretton at Madison and there is an extensive picture of the motorneuronal types of synapses in the worm, as well as the neural architecture (see Stretton, 1978, 1985 for further references). However, the way that the elements in the circuit combine to produce motion is not understood. The present report examines the viability of a mechanism for control of locomotion. Ascaris has approximately 300 neurons and, of these, 80 or so, including interneurons, control locomotion. The neural architecture can be thought of as consisting of five repetitions of a basic pattern of eleven motor neurons, some excitatory and some inhibitory. There is a dorsal nerve cord and a ventral nerve cord, which synapse onto dorsal and ventral muscle cells, respectively. Here we focus on the propagation of a wave in a single chain of muscles which could represent either the dorsal or ventral chain, and do not address the question of coordination of the two cords.
Teaching Science And Engineering-Related Topics Using Experiential Methods: An Action-Research Study

This article describes a portion of a long-term action-research project investigating the teaching of the science of transportation to high school students using the case study or experiential method. Other aspects integrated with the project-oriented study are the use of Constructivist theory, the Socratic Method, and the incorporation of competitiveness and accountability as experienced more typically in a business rather than an education environment. The authors describe the role of the Institute, the need for intervention, and the framing of assignments to make a broad range of topics in engineering, science, and management among others within reach of 9th to 12th grade high school students. By constantly monitoring students’ comprehension of complex material, the faculty, staff and professionals got new insight into their own practice as teacher educators. The ongoing action research intends to follow students after the completion of the program to measure the sustainability of their learning experience.
Variable selection on Eurosta's gall size, III: Can an evolutionary response to selection be detected?

Standard quantitative genetic theory predicts that when a trait is exposed to selection, the between-generation change in the phenotypic mean, Δzi, will be equal to the product of the trait's heritability and the selection differential, h2S. By extension, this theory implies that if a number of replicate populations are exposed to varying intensities of selection, the between-generation changes in means should covary with the selection differential applied. This relationship offers an opportunity for a statistical test to detect evolutionary change when selection is measured in replicate populations. If an evolutionary response to phenotypic selection occurs, the regression of over Si, where i indicates population, will have a positive slope. This statistical test was applied to data on the insect Eurosta solidaginis (Diptera: Tephritidae). The larvae of this fly induce galls on the stems of the host plant, Solidago altissima (Asteraceae). Previous work has shown that gall size is a heritable trait of the insect. Further, size-dependent attack on Eurosta larvae by parasitoids selects for larger gall size (Weis and Abrahamson, 1986). Long-term data on phenotypic selection in 16 populations across 5 generations were analyzed for selection response. Apparent upward evolutionary responses were seen in 2 of the 4 between-generation transitions. However, no response was seen when the analysis was applied to the cumulative change in gall size. Examination of the data suggested that some of the change in mean gall size was a developmental response to spatial and temporal variation in the environment. Non-linear developmental effects of environment, when combined with non-linear fitness functions, can induce a spurious selection response; these non-linear relationships can account for the apparent evolutionary change gall size found in the by-generation analysis. Thus, there is no reliable evidence for evolutionary change in Eurosta's gall size over the generations studied. Stasis of gall size in the face of ongoing selection may be due to counterbalancing selection on the gallmaker imposed by host plant resistance.
Multivariate vertex splines and finite elements

Abstract The objective of this paper is to present a unified study of multivariate super vertex splines with emphasis on the construction procedure and an application to least-squares approximation with interpolatory constraints. Both simplicial and parallelepiped partitions are studied in some detail, and in the bivariate setting, even a partition consisting of both triangles and parallelograms is considered. When the polynomial degree is allowed to be sufficiently large as compared to the order of smoothness, it is clear that vertex splines can be constructed by working on each simplex or parallelepiped separately as long as certain suitable normal derivative constraints are imposed on the boundary faces. Our constructive procedure will take a different route. Instead of normal derivatives, we impose extra interpolatory conditions at the “vertices”. This gives rise to the notion of “super splines” introduced in this paper. It should also be emphasized that the view point of considering a basis of piecewise polynomials with smallest possible supports so that the full approximation order is preserved makes vertex splines different from the standard approach in finite elements. After all, if the polynomial degree is required to be lower, it is necessary to work on at least three adjacent simplices or parallelepipeds simultaneously in constructing a basis of vertex splines.
A multimodel approach to stochastic nash games

A decentralized filtering and control scheme is presented for obtaining low-order Nash equilibrium strategies for decision makers using different models of the same large-scale system. Multiparameter singular perturbations are employed to capture the multimodel nature of the fast dynamic subsystems interconnected through slow dynamic variables. The small parameters are appropriately scaled so that the variables in both time scales are well defined. The decision makers have decentralized information structures and are constrained to use only finite dimensional compensators of a specified dimension. It is shown that the proposed scheme is in fact the asymptotic limit of the exact solution as the small parameters go to zero.
Effect of thiocyanate on the corrosion and passivation behaviour of copper and iron: laser Raman spectroscopy and photoelectrochemical studies

Abstract The effect of small quantities (0.005–0.02 M) of added thiocyanate on the corrosion and passivation behavior of copper and iron in borate buffer solution (pH 8.4) was examined using cyclic voltammetry, laser Raman spectroscopy, and photoelectrochemical techniques. Anodic dissolution currents are significantly increased by the of SCN− and new surface phases are formed. Thiocyanate was found to cause passivity breakdown on iron but not on copper. Corrosion films of CuSCN, as well as Fe(II) and Fe(III) thiocyanates, have been identified spectroscopically. The surface coatings on Cu and Fe exhibited significant photoeffects. CuSCN was characterized to have p-type semiconductivity with a band gap of 2.9 eV and a flat band potential of −0.17 V vs sce in 0.01 M KSCN-borate buffer solution.
Rethinking the Telescope for a Sharper View of the Stars

ASTRONOMY T winkling specks in the firmament might be good enough for poets and children's nursery rhymes, but astronomers need to do better. For decades, they have tried to transform these featureless points of light into distinct images—of galaxies, nebulae, binary stars, even features on single
Hispanic-Americans, Mobile Advertising and Mobile Services

The literature on marketing to Hispanics and the use of mobile-based marketing methods continues to grow. However, to our knowledge, no research has been published on Hispanic use and acceptance of mobile marketing channels; this research addresses that gap. The study investigates various aspects of mobile channel services including advertising among Hispanic-Americans and non-Hispanic-Americans. The results indicate significant differences between Hispanic-Americans and others in the usage of mobile services, satisfaction with mobile services, and attitudes toward mobile advertising, as well as within Hispanic-Americans based on their strength of ethnic identification. The managerial and theoretical implications are discussed.
Catalytic reduction of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) by cobalt(I) salen electrogenerated at vitreous carbon cathodes

Abstract Cyclic voltammetry, controlled-potential electrolysis, GC, GC–MS, HPLC, and HPLC–ESI–MS have been employed to investigate the catalytic reduction of 1,1,2-trichloro-1,2,2-trifluoroethane (chlorofluorocarbon 113, CFC-113, or Freon TM 113) by cobalt(I) salen electrogenerated at a carbon cathode in dimethylformamide (DMF) containing tetra- n -butylammonium tetrafluoroborate (TBABF 4 ) as a supporting electrolyte. A cyclic voltammogram for the reduction of cobalt(II) salen in the presence of excess CFC-113 exhibits a large prewave, attributed to both the formation of a 1,1-dichloro-1,2,2-trifluoroethylcobalt(III) salen complex and its reduction to chlorotrifluoroethene and cobalt(II) salen. This prewave is followed by a smaller wave which involves the reduction of cobalt(II) salen to cobalt(I) salen; a slower catalytic reaction of chlorotrifluoroethene to form trifluoroethene takes place at this same potential, but only when CFC-113 has been completely consumed. Controlled-potential electrolyses carried out at a potential slightly more negative than this second wave also lead to other products, one confirmed to be 1,1,1,2-tetrafluoroethane and at least two other species suspected to be difluoro compounds. From results obtained by means of cyclic voltammetry and controlled-potential electrolysis, along with already published knowledge about the electrochemistry of cobalt-containing complexes, a mechanism is proposed to explain our findings. Catalyst death is also addressed in the light of data from controlled-potential electrolysis and from experiments done with the aid of HPLC and HPLC–ESI–MS.
Ethics in Terms of Hypothetical Imperatives

The affinity of moral rules—and of value judgements in general—to imperatives has often been pointed out by philosophers. It has been argued recently with admirable clarity in Mr. R. M. Hare’s The Language of Morals. But most advocates of this view follow Kant in regarding moral rules as non-hypothetical, i.e. categorical, imperatives. I shall try to show that this view is mistaken, and that moral rules are in actual fact hypothetical imperatives. Indeed, I shall argue that on closer analysis all imperatives turn out to be hypothetical, even though their protasis is often left unexpressed.
The role of dynamically correlated conformational equilibria in the folding of macromolecular structures. A model for the design of folded dendrimers

Abstract This review explores how the occurrence of synchronized conformational fluctuations within a folded macromolecular structure contributes to its structural and functional properties. These fluctuations interconvert multiple conformational states that are separated by small energetic barriers. Internal motions that occur on very short time and length scales in proteins greatly influence processes such as ligand binding, catalysis, allostery and thermodynamic stability. Furthermore, recent evidence suggests that the residual conformational fluctuations are correlated within the folded structure of proteins. These observations suggest that the mechanism by which the residual motions contribute to the thermodynamic stability of proteins is related to the chiral amplification phenomenon observed in helical polymers and supramolecular assemblies. In these synthetic systems, extensive theoretical and experimental studies have demonstrated that conformational synchronization that occurs over extended distances amplifies small energetic differences relating conformational states leading to highly stable folded materials. The effect of these synchronized fluctuations on the conformational properties provides a model for the design of dendrimers that adopt folded conformations and amplify chiral structural perturbations.
Effect of variations in diameter and density on the statistics of aligned array carbon-nanotube field effect transistors

This paper describes a systematic experimental and theoretical analysis of performance variations in transistors that use aligned arrays of single-wall carbon nanotubes (SWNTs) grown on quartz substrates. Theoretical models, calibrated using measurements on statistically relevant numbers of transistors that each incorporate an individual aligned semiconducting SWNT, enable separate examination of different contributors to measured variations in transistors that incorporate arrays of SWNTs. Using these models and associated experiments, we study the scaling of the statistics of key performance attributes in transistors with different numbers of incorporated SWNTs and reveal long-range spatial nonuniformities in the distributions of SWNT diameters as the main contributor to observed performance variability.
The Socialist Party of Argentina, 1890-1930

* Acknowledgments * Preface * Chapters *1. Emergence: 1890-1895 *2. Organization and Recruitment: 1895-1900 *3. Repression and Growth: 1900-1910 *4. Palacios: 1904-1908 *5. Reform: 1910-1913 *6. Elections, Congress, and the 'Palacios Affair': 1914-1915 *7. Yrigoyen, War, and Labor: 1916-1919 *8. Socialists and Radicals after the 'Semana Tragica': 1919-1921 *9. Socialists and the Alvear Administration: 1922-1927 *10. Schism: 1927-1930 *11. Conclusion * Appendices * Notes * Bibliography * Index
Transport of d-glucose by brush border membranes isolated from the renal cortex

Abstract The transport of d -glucose by brush border membranes isolated from the rabbit renal cortex was studied. At concentrations less than 2 mM, the rate of d -glucose uptake increased linearly with the concentration of the sugar. No evidence was found for a “high-affinity” (μM) saturable site. Saturation was indicated at concentrations of d -glucose greater than 5 mM. The uptake of d -glucose was stereospecific and selectively inhibited by d -galactose and other sugars. Phlorizin inhibited the uptake of d -glucose in the presence and absence of Na + . The glycoside was a potent inhibitor of the efflux of d -glucose. Preloading the brush border membrane vesicles with d -glucose, but not with l -glucose, accelerated exchange diffusion of d -glucose. These results demonstrate that the uptake of d -glucose by renal brush borders represents transport into an intravesicular space rather than solely binding. The rate of d -glucose uptake was increased when the Na + in the extravesicular medium was high and the membranes were preloaded with a Na + -free medium. The rate of d -glucose uptake was inhibited by preloading the brush border membranes with Na + . These results are consistent with the Na + gradient hypothesis for d -glucose transport in the kidney. Thus, the presence of a Na + -dependent facilitated transport of d -glucose in isolated renal brush border membranes is indicated. This finding is consistent with what is known of the transport of the sugar in more physiologically intact preparations and suggests that the membranes serve as an effective model system in examining the mechanism of d -glucose transport in the kidney.
Enhancing Motor Learning Through Peer Tutoring

The purpose of this study was to examine the efficacy of incorporating mnemonic memory aids and having a subject teach another person a given task (peer tutoring) as a method of enhancing task acquisition and recall by the subject and to discuss the implications for occupational therapists who instruct clients in motor tasks such as therapeutic exercise programs. Sixty-seven college students were randomly assigned to one of three groups using different teaching methods for the purpose of learning a motor task, specifically the American Sign Language alphabet. Subjects who were taught using mnemonics and peer tutoring scored significantly better on post-testing two days following instruction than did the control groups. Use of these techniques did not increase direct teaching time by the instructor, nor did they incur additional costs. Thus, these techniques may be easily incorporated into client education to improve recall and performance.
An online tutoring system with instant responses

In this paper, we describe an online tutoring system currently under development. The online tutoring system is designed with a goal to help nontraditional students learn subjects that require a significant amount of assistance from tutors, who may only be available on campus. The subjects include but not limited to Calculus, Algebra, Computer Science, Physics, and the like. This system makes it possible for students to request instant help from tutors online anytime anywhere. An accounting subsystem allows instructors to monitor students' performance and tutors' efficiency. A Latex interface is built to ease input special notations and Mathematical equations.
Search for >200 TeV photons from Cygnus X-3 in 1988 and 1989.

Over a period of 16 months from April 1988 to August 1989, we have monitored the flux of cosmic-ray showers with energies above 2{times}10{sup 14} eV. We used a two-level array of scintillators covering an area of 3{times}10{sup 4} m{sup 2}. Counters on the surface measure the size and direction of each shower while counters buried 3 m beneath the surface sample the muons. By selecting showers with relatively few muons (less than one-tenth the average) the background of hadron-induced showers should be reduced by a factor of 150 or more while showers started by {gamma} rays should not be affected by this cut. We find no evidence for an excess from the direction of Cygnus X-3 either in ordinary showers or in muon-poor showers. For energies above 2{times}10{sup 14} eV, with 90% confidence, we find the excess flux of cosmic rays from the direction of Cygnus X-3 to be less than 1.3{times}10{sup {minus}13} cm{sup {minus}2}s{sup {minus}1} and the flux of photons (assuming they produce muon-poor showers) to be less than 1.5{times}10{sup {minus}14} cm{sup {minus}2}s{sup {minus}1}. This limit is substantially below the level of signals reported by earlier work. The period of observation included the intense radio bursts of Junemore » and July 1989. A portion of the data covering the 77-day period surrounding these events also showed no evidence for an excess.« less
The origins and evolution of the disease concept of treatment

Objective: The disease concept of treatment (DCT) has been the dominant treatment model for alcoholism in the United States for the last 30 years. This article sheds light on this treatment model by tracing its historical origins and its evolution in institutions. Method: Accounts from the published literature on Alcoholics Anonymous (AA) and early alcoholism treatment programs were culled for insights regarding the development of DCT. Early examples of AA facilities, state mental hospital alcoholism units, detoxification units, and outpatient alcoholism clinics are described as they evolved. The important role of AA in this process is detailed. Accounts are given of the interaction between professionals and alcoholism counselors during the period in which DCT was developed in these institutions. Results: It was found that all of the current types of alcoholism treatment programs had their origins in early, informal AA facilities except for outpatient alcoholism clinics. DCT evolved concurrently in AA fac...
Steric effects on multivalent ligand-receptor binding: exclusion of ligand sites by bound cell surface receptors

Steric effects can influence the binding of a cell surface receptor to a multivalent ligand. To account for steric effects arising from the size of a receptor and from the spacing of binding sites on a ligand, we extend a standard mathematical model for ligand-receptor interactions by introducing a steric hindrance factor. This factor gives the fraction of unbound ligand sites that are accessible to receptors, and thus available for binding, as a function of ligand site occupancy. We derive expressions for the steric hindrance factor for various cases in which the receptor covers a compact region on the ligand surface and the ligand expresses sites that are distributed regularly or randomly in one or two dimensions. These expressions are relevant for ligands such as linear polymers, proteins, and viruses. We also present numerical algorithms that can be used to calculate steric hindrance factors for other cases. These theoretical results allow us to quantify the effects of steric hindrance on ligand-receptor kinetics and equilibria.
Comparison of exercise radionuclide angiography with thallium SPECT imaging for detection of significant narrowing of the left circumflex coronary artery.

Abstract Although quantitation of exercise thallium tomograms has enhanced the noninvasive diagnosis and localization of coronary artery disease, the detection of stenosis of the left circumflex coronary artery remains suboptimal. Because posterolateral regional wall motion during exercise is well assessed by radionuclide angiography, this study determined whether regional dysfunction of the posterolateral wall during exercise radionuclide angiography is more sensitive in identifying left circumflex disease than thallium perfusion abnormalities assessed by single-photon emission computed tomography (SPECT). One hundred ten consecutive patients with CAD were studied, of whom 70 had a significant stenosis of the left circumflex coronary artery or a major obtuse marginal branch. Both regional function and segmental thallium activity of the posterolateral wall were assessed using visual and quantitative analysis. Left ventricular regional function was assessed objectively by dividing the left ventricular region of interest into 20 sectors; the 8 sectors corresponding to the posterolateral free wall were used to assess function in the left circumflex artery distribution. Similarly, using circumferential profile analysis of short-axis thallium tomograms, left ventricular myocardial activity was subdivided into 64 sectors; the 16 sectors corresponding to the posterolateral region were used to assess thallium perfusion abnormalities in the left circumflex artery territory. Qualitative posterolateral wall motion analysis detected 76% of patients with left circumflex coronary artery stenosis, with a specificity of 83%, compared with only 44% by qualitative thallium tomography (p A similar analysis applied to the interventricular septum revealed a higher predictive accuracy for detecting left anterior descending coronary artery stenosis by qualitative thallium SPECT, with a sensitivity of 80% and a specificity of 71%, compared with a sensitivity of 68% and a specificity of 57% by qualitative radionuclide angiography. Quantitation of thallium activity in both septal and anterior regions provided no additional insight for detection of left anterior descending artery stenosis. Thus, for noninvasive detection of left circumflex coronary artery disease, the data suggest that qualitative exercise radionuclide angiography is preferable to qualitative thallium SPECT and provides comparable information to quantitative thallium analysis.
The cup runneth over: lessons from the ever-expanding pool of primary immunodeficiency diseases

A recent surge in newly described primary immunodeficiencies (PIDs) has highlighted new physiological and pathophysiological pathways that affect the immune system. Furthermore, the study of individuals with PIDs has substantially improved our understanding of basic cellular and signalling pathways in host defence and immune regulation. Single-gene defects can lead to disease manifestations that range from extremely narrow infectious phenotypes to remarkably broad multisystem effects. Hypomorphic or hypermorphic gene mutations often occur in human diseases; when coupled with the fact that humans are exposed to naturally encountered antigens and pathogens, this helps to make the case that the study of immunological diseases in humans should be at the forefront of basic immunological research.
DIFFERENTIAL EFFECTS OF SEATING ARRANGEMENTS ON DISRUPTIVE BEHAVIOR OF FIFTH GRADE STUDENTS DURING INDEPENDENT SEATWORK

We investigated teacher versus student seat selection in the context of group and individual seating arrangements. Disruptive behavior during group seating occurred at twice the rate when students chose their seats than when the teacher chose. During individual seating, disruptive behavior occurred more than three times as often when the students chose their seats. The results are discussed in relation to choice and the matching law.
Brecht, Shakespeare, and the Dynamics of Black Humor

In act 1, scene 3 of Bertolt Brecht's The Threepenny Opera, Jonathan Jeremiah Peachum, the ‘Beggar King,’ rebukes his employees for their healthy, well‐fed appearance: PEACHUM tries a false limb on...
Assessing the Value of Information for long-term structural health monitoring

In the field of Structural Health Monitoring, tests and sensing systems are intended as tools providing diagnoses, which allow the operator of the facility to develop an efficient maintenance plan or to require extraordinary measures on a structure. The effectiveness of these systems depends directly on their capability to guide towards the most optimal decision for the prevailing circumstances, avoiding mistakes and wastes of resources. Though this is well known, most studies only address the accuracy of the information gained from sensors without discussing economic criteria. Other studies evaluate these criteria separately, with only marginal or heuristic connection with the outcomes of the monitoring system. The concept of “Value of Information” (VoI) provides a rational basis to rank measuring systems according to a utility-based metric, which fully includes the decision-making process affected by the monitoring campaign. This framework allows, for example, an explicit assessment of the economical justifiability of adopting a sensor depending on its precision. In this paper we outline the framework for assessing the VoI, as applicable to the ranking of competitive measuring systems. We present the basic concepts involved, highlight issues related to monitoring of civil structures, address the problem of non-linearity of the cost-to-utility mapping, and introduce an approximate Monte Carlo approach suitable for the implementation of time-consuming predictive models.
Soil Remaining on Fabrics after Laundering as Evaluated by Response Surface Methodology

Response surface methodology was used to visualize the interactive effects of de tergent concentration, agitation time, and wash temperature on removal of soil from fabrics. Plots of the whiteness ...
Environmental context and drug history modulate amphetamine-induced c-fos mRNA expression in the basal ganglia, central extended amygdala, and associated limbic forebrain.

The context in which amphetamine is administered modulates its ability to induce both behavioral sensitization and immediate early gene expression. When given in a novel test environment amphetamine produces greater levels of c-fos and arc mRNA expression in many brain regions relative to when it is given in the home cage. The purpose of the current study was to determine if environment and drug history interact to influence amphetamine-induced c-fos mRNA expression. Rats with a unilateral 6-hydroxydopamine lesion were treated for 7 days with saline or 0.5 mg/kg of d-amphetamine (i.v.) in a distinct and relatively novel test environment (Novel), or in their home cage (Home). Following a 10-12-day withdrawal period, a challenge injection of either saline or 0.5 mg/kg d-amphetamine was administered. In situ hybridization histochemistry was used to examine c-fos mRNA expression in several regions of the basal ganglia, the central extended amygdala, and limbic forebrain. In most brain regions amphetamine given in the Novel environment produced greater c-fos mRNA expression than when given it was given at Home, and drug history had no effect on amphetamine-induced c-fos mRNA expression. However, within the subthalamic nucleus, substantia nigra reticulata, and central nucleus of the amygdala prior experience with amphetamine in the Novel but not Home environment enhanced the effect of an amphetamine challenge injection on c-fos mRNA expression. In contrast, there was a decrease in c-fos mRNA expression in amphetamine-pretreated animals, regardless of environmental context, in the ventral portion of the far caudal striatum. Reexposure to an environment previously paired with amphetamine produced a conditioned increase in c-fos mRNA expression in portions of the caudate-putamen, the subthalamic nucleus, the nucleus accumbens shell and a conditioned decrease in c-fos mRNA expression in the central nucleus of the amygdala. We conclude that environmental context and drug history interact to alter the basal ganglia and central extended amygdala circuitry engaged by subsequent exposure to amphetamine, or exposure to an environment previously paired with amphetamine.
Conceptualizations of good citizenship and political participation

Theorists have variously defined what it means to be a good citizen. But how do citizensthemselves views their responsibilities? And is there any relationship between a person's view of citizenship and his or her political participation? This paper uses a combination of methods to explore these issues. A Q method study reveals four citizenship perspectives that provide evidence for striking differences in how people define the participatory responsibilities of a good citizen. An exploratory survey analysis finds that the four citizenship perspectives are significantly related to political behavior, even when socioeconomic status and attitudinal variables related to participation are controlled. While adding to our understanding of participation, these findings also underscore the importance of investigating the conceptualizations of citizens to gain more complete understandings of how political systems work.
Oxidative phosphorylation and respiration by liver mitochondria from polychlorinated biphenyl-intoxicated rats☆

Abstract Respiration and oxidative phosphorylation by intact hepatic mitochondria isolated from rats fed polychlorinated biphenyls (PCBs) were studied polarographically using glutamate and succinate as substrates. High levels of PCBs fed for 3 weeks resulted in an increase in respiration and in ADP/O ratios. However, when PCBs were fed to rats for 20 weeks at 100 ppm, there was no significant difference from control values. Gas Chromatographic determination of PCB levels in mitochondrial fractions revealed 2–3 μg/mg of protein for treated rats in the acute study and about 0·3 μg/mg in the chronic study. Addition of PCBs in vitro to control rat liver mitochondria caused an inhibition of oxidative phosphorylation and respiration at or above a concentration of 50 μg/mg of mitochondrial protein. Since 2,4-dinitrophenol did not initiate uncontrolled respiration in PCB-inhibited rat liver mitochondria, and since inhibition occurred with both substrates, it appears that PCB inhibition in vitro occurs at a site along the respiratory chain.
Forward scattering at collider energies and eikonal unitarization of the odderon

Abstract The continuing increase of hadron total cross sections up to the highest energies currently available can most naturally be understood through an eikonal mechanism, leading to the saturation of the Froissart bound. This picture can be motivated in a nonperturbative treatment of QCD, e.g., in the large-N limit. It is then natural to ask whether this same mechanism would lead to the maximal allowed behavior for the difference of the particle-particle and antiparticle-particle cross section, i.e., the “maximal odderon”. We shall show in this paper that, using eikonals which are dynamically meaningful for high-energy hadron-hadron scattering at collider energies, this behavior is not possible.
Childbirth education classes: effects on attitudes toward childbirth in high-risk indigent women.

To determine if childbirth education classes influence attitudes toward the childbirth experience in high-risk medically indigent patients, a questionnaire study of 50 women was conducted. The 20 study subjects who completed childbirth education classes had significantly more positive attitudes than those 30 control subjects who participated only in the labor and delivery class given during clinic hours.
Influence of surfactants in aqueous-based polymeric dispersions on the thermomechanical and adhesive properties of acrylic films.

Good adhesion between a polymeric film and the surface of a solid substrate is critical to the performance of coated pharmaceutical products. Previous research has shown that tablet wettability by ...
Catastrophic football injuries: 1977-1998.

The primary purpose of this study was to investigate the occurrence of catastrophic American football head and spine injuries, in an attempt to reduce their frequency. We analyzed epidemiological and medical data from 1977 through 1998. Catastrophic football injuries are defined as football injuries that result in death, brain or spinal cord injury, or cranial or spinal fracture. All studied cord injuries involved the cervical region. During the period covered by this study, 118 athletes died as a direct result of participation in the skills of football, 200 football players received a permanent cervical cord injury, and 66 sustained a permanent cerebral injury. Most cervical injuries occurred to defensive players during the act of tackling. The axial loading mechanism of spinal cord injury was identified in 27% of tackling injuries. To further reduce catastrophic injuries, players must stop tackling with the head down and using the head as a battering ram; instead, players should use the shoulder for blocking and tackling. Other recommendations for reducing catastrophic injuries are presented. Language: en
Prostaglandin D synthase in microvessels from the cat cerebral cortex

Abstract Microvessels, a mixture composed predominantly of small arterioles and capillaries (7–80μ diameter), were isolated from the rat cerebral cortex by selective nylon sieving and glass bead elutriation. The morphology and purity of the microvessel and cerebral cortex filtrate (virtually free of vascular contamination) were monitored by light microscopy and by the activity of several enzymes: γ-glutamyl transpeptidase, GSH-transferase, prostacyclin synthase and PGD synthase. Prostacyclin and PGD synthesizing activities as well as γ-glutamyl transpeptidase activity were localized to the microvessels of the rat cerebral cortex whereas GSH-S-transferase was restricted to the non-vascular filtrate function. The characteristics of the PGD synthase were similar to those of the purified enzyme previously described for the rat brain. The microvessel (MV) PGD synthase was localized to the cytosol fraction of the microvessels and did not require reduced glutathione for activity. The enzyme was inhibitd by pre-incubation with p-hydroxymercuribenzoate (lmM) or N-ethylmaleimide (lmM). The MV PGD synthase saturated at 15–20μM PGH2, exhibited an apparent KM of 9.6μM, and a pH optimum of 8.0–8.1. These findings suggest roles for both prostacyclin and PGD synthesis by the rat cerebral vasculature in the autoregulation of cerebral blood flow and/or function. These studies also indicate that the major source of PGI2 and PGD2 synthesis by rat brain homogenates is the microvasculature.
Fair weather and storm sand transport on the Long Island, New York, inner shelf

Both spring-summer and fall-winter sand transport have been observed on the Long Island, New York, inner shelf at water depths of 20-22 m using a radio-isotope sand tracer system. The extent of dispersal of the tagged, fine sand was measured at 3 week intervals in two 70 day experiments. In the late spring and early summer, movement was primarily diffusive in nature, extending 100 m around the line of tracer injection, while late fall-winter patterns had strong advective features, including an ellipsoidal outline extending approximately 1500 m westward of the injection points after the passage of several storms with strong northeasterly winds. Near-bottom current observations made with Savonius rotor sensors identify the event responsible for the bulk of the transport over the 135 day observation period as a storm flow of 2 days duration. Tracer and current observations together suggest that westward winter storm flow along the Long Island shelf is the major mechanism of sand transport at these depths on a yearly time scale. A least-squares fit of several of the observed winter patterns with a plume model yields average sediment mass flux lower bounds of 3.2 × 10−3 gm/cm/sec and 1.7 × 10−1 gm/cm/sec for ‘typical’ and extreme winter storm activity.
A Design-based Approach to Fostering Understanding of Global Climate Change

To prepare students to make informed decisions and gain coherent understanding about global climate change, we tested and refined a middle school inquiry unit that featured interactive visualizations. Based on evidence from student pre-test responses, we increased emphasis on energy transfer and transformation. The first iteration improved comprehension of the visualizations resulting in better understanding of energy transfer (n = 67). The second iteration improved understanding of energy transformation (n = 109) by adding pivotal cases, reducing deceptive clarity, and emphasizing distinguishing of ideas. Focusing student investigations in the second version allowed students to make more normative, personally relevant decisions related to their energy use. These iterative refinements reflected knowledge integration principles and offer guidance for designers of inquiry units.
Communicative NGOMSL: Development of an Evaluation Method for a Text-Based Communication System

Goals, Operators, Methods, and Selection rules (GOMS) is an analytic method and a model evaluation method for the knowledge necessary for a user to perform tasks in a system, and Natural GOMS Language (NGOMSL), a version of GOMS, is an attempt to define a language so that the GOMS model can be precisely constructed in a structured way. This study proposes Communicative NGOMSL, which is an extension of NGOMSL intended to accommodate modeling of text-based communication among two or more individuals. Besides the properties of GOMS techniques in evaluation, Communicative NGOMSL additionally considers common ground and communication time: Common ground refers to the mutual knowledge, beliefs, and assumptions of participants in communication, and communication time refers to the time that an individual waits for another to respond. The analysis of a Communicative NGOMSL model provides some information for a common task goal in a text-based communication system: (a) the relationship between the grounding proces...
Kinetics and regioselectivity of ring opening of 1-bicyclo[3.1.0]hexanylmethyl radical.

Rate constants for the rearrangement of 1-bicyclo[3.1.0]hexanylmethyl radical (2) to 3-methylenecyclohexenyl radical (3) and 2-methylenecyclopentyl-1-methyl radical (1) were measured using the PTOC−thiol competition method. The ring-expansion pathway is described by the rate equation, log(k/s-1) = (12.5 ± 0.1) − (4.9 ± 0.1)/θ; the non-expansion pathway is described by log(k/s-1) = (11.9 ± 0.6) − (6.9 ± 0.8)/θ. Employing the slower trapping agent, tri-n-butylstannane, favors methylenecyclohexane over 2-methyl-methylenecyclopentane by more than 120:1 at ambient or lower temperatures.
Primary sequence and solution conformation of ferrocytochrome c-552 from Nitrosomonas europaea.

Abstract Cytochrome c -552 from Nitrosomonas europaea is a 9.1-kDa monoheme protein that is a member of the bacterial cytochrome c -551 family. The gene encoding for c -552 has been cloned and sequenced and the primary sequence of the product deduced. Proton resonance assignments were made for all main-chain and most side-chain protons in the diamagnetic, reduced form by two-dimensional NMR techniques. Distance constraints (1056) were determined from nuclear Overhauser enhancements, and torsion angle constraints (88) were determined from scalar coupling estimates. Solution conformations for the protein were computed by the hybrid distance geometry-simulated annealing approach. For 20 computed structures, the root mean squared deviation from the average position of equivalent atoms was 0.84A ( σ =0.12) for backbone atoms over all residues. Analysis by residue revealed there were three regions clearly less well defined than the rest of the protein: the first two residues at the N-terminus, the last two at the C-terminus, and a loop region from residues 34 to 40. Omitting these regions from the comparison, the root mean squared deviation was 0.61A ( σ =0.13) for backbone atoms, 0.86A ( σ =0.12) for all associated heavy atoms, and 0.43A ( σ =0.17) for the heme group. The global folding of the protein is consistent with others in the c -551 family. A deletion at the N-terminus relative to other family members had no impact on the global folding, whereas an insertion at residue 65 did affect the way the polypeptide packs against the methionine-ligated side of the heme. The effects of specific substitutions will be discussed. The structure of c -552 serves to delineate essential features of the c -551 family.
A Posteriori Error Estimates for DDDAS Inference Problems

Abstract Inference problems in dynamically data-driven application systems use physical measurements along with a physical model to estimate the parameters or state of a physical system. Errors in measurements and uncertainties in the model lead to inaccurate inference results. This work develops a methodology to estimate the impact of various errors on the variational solution of a DDDAS inference problem. The methodology is based on models described by ordinary differential equations, and use first-order and second-order adjoint methodologies. Numerical experiments with the heat equation illustrate the use of the proposed error estimation machin- ery.
The Date of Tatian's Oration

Various dates have been given for Tatian's Oration to the Greeks, ranging from 152 to 172. None of these dates is correct, since the treatise was written after the year 176, perhaps in 177 or 178. In the spring of 175 the Roman empire was shaken by the almost accidental revolt of Avidius Cassius, governor of Syria. Acting on the rumor that Marcus Aurelius had died, the governor proclaimed himself emperor. Egypt joined Cilicia, Syria, and Judaea; but the revolt was crushed in little more than three months. The emperor promised clemency (coins of the following year mention Clementia Aug. ) and kept his promise. He then made a journey to the east with the empress Faustina and their son Commodus, passing through Syria but avoiding Antioch, the center of the revolt. Early in 176, after wintering in Alexandria, they visited Antioch and went on to Cappadocia, where Faustina's sudden death was followed by a magnificent funeral.
Dynamic structure factor study of diffusion in strongly sheared suspensions

Diffusion of neutrally buoyant spherical particles in concentrated monodisperse suspensions under simple shear flow is investigated. We consider the case of non-Brownian particles in Stokes flow, which corresponds to the limits of infinite Peclet number and zero Reynolds number. Using an approach based upon ideas of dynamic light scattering we compute self- and gradient diffusion coefficients in the principal directions normal to the flow numerically from Accelerated Stokesian Dynamics simulations for large systems (up to 2000 particles). For the self-diffusivity, the present approach produces results identical to those reported earlier, obtained by probing the particles' mean-square displacements (Sierou & Brady, J. Fluid Mech. vol. 506, 2004 p. 285). For the gradient diffusivity, the computed coefficients are in good agreement with the available experimental results. The similarity between diffusion mechanisms in equilibrium suspensions of Brownian particles and in non-equilibrium non-colloidal sheared suspensions suggests an approximate model for the gradient diffusivity: ${\textsfbi D}^\triangledown\,{\approx}\,{\textsfbi D}^s/S^{eq}(0)$, where ${\textsfbi D}^s$ is the shear-induced self-diffusivity and $S^{eq}(0)$ is the static structure factor corresponding to the hard-sphere suspension at thermodynamic equilibrium.