cssi/SciSciGPT-SciSciNet huggingface dataset:
Barwise: Infinitary Logic and Admissible Sets

§0. Introduction . In [16], Barwise described his graduate study at Stanford. He told of his interactions with Kreisel and Scott, and said how he chose Feferman as his advisor. He began working on admissible fragments of infinitary logic after reading and giving seminar talks on two Ph.D. theses which had recently been completed: that of Lopez-Escobar, at Berkeley, on infinitary logic [46] (see also the papers [47], [48]), and that of Platek [58], at Stanford, on admissible sets. Barwise's work on infinitary logic and admissible sets is described in his thesis [4], the book [13], and papers [5]—[16]. We do not try to give a systematic review of these papers. Instead, our goal is to give a coherent introduction to infinitary logic and admissible sets. We describe results of Barwise, of course, because he did so much. In addition, we mention some more recent work, to indicate the current importance of Barwise's ideas. Many of the central results are stated without proof, but occasionally we sketch a proof, to indicate how the ideas fit together. Chapters 1 and 2 describe infinitary logic and admissible sets at the time Barwise began his work, circa 1965. From Chapter 3 on, we survey the developments that took place after Barwise appeared on the scene. §1. Background on infinitary logic . In this chapter, we describe the situation in infinitary logic at the time that Barwise began his work. We need some terminology. By a vocabulary , we mean a set L of constant symbols, and relation and operation symbols with finitely many argument places. As usual, by an L -structure M , we mean a universe set M with an interpretation for each symbol of L .
A longitudinal examination of internet‐based customer service system usage in small companies

Purpose – New internet technologies are not always readily accepted by target users – especially by small companies. More effective identification of target market characteristics and requirements associated with the adoption and ongoing usage of internet‐based service systems (NCSSs) is therefore needed. Drawing on adoption theory, this research aims to assess pre‐launch survey, legacy and longitudinal data to evaluate factors that encourage small companies to use NCSSs.Design/methodology/approach – The roll out and ongoing usage of a new NCSS are tracked within a single channel of dental offices over a 185‐week period. Logistic and multiple regression analyses are utilized to examine the influences of system attributes, attributes of the target user group, supplier promotional activity and system completeness on ongoing usage.Findings – Pre‐launch survey data is an ineffective predictor of ongoing small company NCSS usage. The best predictors are indicators of organizational readiness and organizational...
Growth of thick single-crystal layers of yttrium iron garnet by liquid phase epitaxy

Abstract Single crystal films of YIG (yttrium iron garnet) up to about 100 μm thick have been grown on (111) GGG (gadolinium gallium garnet) substrates by the usual LPE (liquid phase epitaxy) method of isothermal dipping in a PbO-B2O3 fluxed melt. Although interface instability arising from constitutional supersaturation is believed to exist during film growth by this method, the film surfaces were found to be generally smooth. Evidence of possible interface breakdown was restricted to the periphery of the wafers and a few other isolated locations.
Recruitment limitation of long-lived conifers: implications for climate change responses

Seed availability and suitable microsites for germination are likely to severely constrain the responses of plant species to climate change, especially at and beyond range edges. For example, range shifts may be slow if seed availability is low at range edges due to low parent-tree abundance or reduced fecundity. Even when seeds are available, climatic and biotic factors may further limit the availability of suitable microsites for recruitment. Unfortunately, the importance of seed and microsite limitation during range shifts remains unknown, since few studies have examined both factors simultaneously, particularly across species' ranges. To address this issue, we assessed seed availability and the factors influencing germination for six conifer species across a large environmental gradient encompassing their elevational ranges. Specifically, we assessed (1) how parent-tree abundance influences annual seed availability; (2) how seed limitation varies across species' ranges; (3) how climatic and biotic fac...
Biphasic changes in phospholipid hydroperoxide levels during renal ischemia/reperfusion

Abstract The involvement of lipid peroxidation in renal ischemia/repurfusion was explored by measuring changes in the cortical content of specific primary lipid hydroperoxides (using chemluminescent detection with HPLC) following ischemia and reperfusion and by correlating the changes in hydroperoxide content with measurements of renal blood flow. Phosphatidylcholine and phosphatidylethanolamine hydroperoxide concentrations were significantly lowered during 30 or 60 min of ischemia (to levels less than 50% of control at 60 min). Following 30 min of renal ischemia, repurfusion resulted in a rebound of phospholipid hydroperoxide tissue content to levels higher than controls. Increased phospholipid hydroperoxide formation was not, however, observed in response to reperfusion following long-term (60 min) ischemia. In separate animals it was demonstrated that following 30 min ischemia and reperfusion, renal blood flow recovers to about 65% of control in 1 h. In contrast, following 60 min ischemia and reperfusion, the renal blood flow remains more highly impaired (less than 25% recovery for periods up to 24 h). These results imply that phospholipid hydroperoxides are produced and accumulate in the kidneys under normal aerobic conditions and that lipid peroxidative activity increases during renal ischemia/reperfusion to an extent dependent on the degree of local blood perfusion.
A review of estrogen replacement therapy use in the prevention and treatment of Alzheimer disease

Abstract Retrospective studies have shown estrogen to be beneficial in preventing all-cause mortality. As women grow older, Alzheimer disease prevalence increases. Cognitive function preservation gains added importance in today's aging society. This article is a review of the available literature on estrogen replacement therapy's association with Alzheimer disease. The basic science data available on estrogen and the central nervous system show a positive effect on cerebral blood flow, brain-derived nerve growth factor synthesis in the hippocampus, and increased production of acetylcholine. Prevention trials show that the relative risk of developing Alzheimer disease in women undergoing estrogen replacement therapy is in the range of 0.4 to 1.9; however, four of the five studies discussed in this article have relative risks less than 1. Treatment trials are all very small, consisting of fewer than 20 patients. There is a consistent benefit seen when women with milder forms of Alzheimer disease undergo estrogen therapy for a few weeks. The benefit is ascertained via cognitive function tests and by subjective clinical assessment. Given the limited nature of the data available, it is impossible to draw any firm conclusions. Estrogen replacement therapy probably does exert a small positive effect on Alzheimer disease progression.
Corrigendum to “Planning extent of resection in epilepsy: Limited versus large resections” [Epilepsy & Behavior 20, Issue 2 (2011) 233–240]

Corrigendum to “Planning extent of resection in epilepsy: Limited versus large resections” [Epilepsy & Behavior 20, Issue 2 (2011) 233–240] Saint V. Okonma, Jeffrey P. Blount, Robert E. Gross⁎ a Department of Neurosurgery, Emory University School of Medicine, Atlanta, GA, USA b Department of Neurosurgery, University of Alabama at Birmingham, Birmingham, AL, USA c Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA d Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
Therapeutic camping for children with end-stage renal disease.

Therapeutic camping experiences for children with end-stage renal disease (ESRD) have proliferated in the United States and abroad. This report is based on the results of a survey designed to accumulate data on the development and implementation of 20 such camps. Children attending camp ranged in age from 1 year to 19 years. Single disease-specific camps were most common, while camps for children with a variety of chronic illnesses, including ESRD, and mainstream camps were also conducted. Facilities were available for hemodialysis and continuous ambulatory peritoneal dialysis, but not automated peritoneal dialysis, in the majority of surveryed camps. Dialysis nurses, pediatric nephrologists, dietitians and social workers were the medical personnel that most frequently participated in the camps. On average, 32 dialysis/transplant patient campers (range 6–100) attended camp for a 1-week session. Therapeutic camping experiences for children with ESRD are extremely successful and attempts to increase the availability of similar camps should be encouraged.
Automotive recycling in the United States: Energy conservation and environmental benefits

The production and use of polymers has been growing and that trend is expected to continue. Likewise, the production of metals from ores is on the rise because of increasing demand. Recycling polymers and residual metals can result in significant energy savings and environmental benefits including a reduction in CO2 emissions. This article describes recycling options for the polymers and metals in end-of-life vehicles.
Identification of a photoreceptor-specific mRNA encoded by the gene responsible for retinal degeneration slow (rds).

Identification of a photoreceptor-specific mRNA encoded by the gene responsible for retinal degeneration slow (rds)
Growth in Students' Attitudes About the Utility of Science Over the Middle and High School Years: Evidence From the Longitudinal Study of American Youth

The purpose of this paper is to track changes in students' attitudes about the utility of science over the middle and high school years using data from the Longitudinal Study of American Youth (Miller, J. D., Hoffer, T., Suchner, R. W., Brown, K. G., and Nelson, C. (1992). LSAY code book: student, parent, and teacher data for 1992 cohort two for longitudinal years one through four (1987–1991). Northern Illinois University, Illinois. Latent variable growth modeling is the technique that was used to examine the growth in students' attitudes about the utility of science. The results of the present study show that the overall trend for students' attitudes about the utility of science is positive. This means that middle and high school students have fairly positive attitudes about the usefulness of science. It is clear from the present analysis that some of the important predictors of attitudes about the utility of science include science self-concept, teacher encouragement of science, and to a lesser extent achievement motivation and science activities. The effects of the peer and parent variables were found to be quite small and statistically nonsignificant. Also it was found that the time-invariant predictors were not statistically significant. Latent variable growth modeling allows one to examine change in attitudes and also examine the effects of time-varying and time-invariant predictors. Substantive and methodological implications of this technique are also discussed.
Methods used for analyses of “environmentally” damaged nucleic acids

Abstract In this review, we present various techniques, currently applied in many laboratories, which are useful in the detection of “environmentally”-induced damage to DNA. These techniques include: (a) chromatographic methods, which allow determination of chemical changes within DNA, be they formation of adducts with or oxidation of bases in DNA; (b) electrophoretic methods, which facilitate finding the site(s) in DNA where that chemical modification occurred; and (c) immunological assays, which help to detect DNA damage using externally produced antibodies that recognize the specific chemical changes in DNA or its fragments, as well as by detection of autoantibodies that develop in response to environmental exposures of animals and humans.
A modeling-based factor extraction method for determining spatial heterogeneity of Ga-68 EDTA kinetics in brain tumors

The ROI method applied to Ga-68 EDTA PET dynamic study data for the quantitative determination of brain tumor BBB permeability assumes that the tumor is homogeneous in terms of Ga-68 EDTA kinetics, even though it is known that brain tumors are highly heterogeneous in structure. The relatively high image noise of Ga-68 PET studies have prevented the examination of Ga-68 EDTA kinetics by nonlinear regression on a single pixel basis. In this study, we have developed an efficient and effective method to separate brain tumor tissue into sub-regions with different Ga-68 EDTA kinetics on a pixel-by-pixel basis. Computer simulation and ten Ga-68 EDTA PET patient studies were used to evaluate the performance of the new method. During a PET dynamic study (total 64 min), 20-25 arterial samples were taken for the input function. Whole-tumor ROIs were defined on T1-weighted MRI images and then copied to the registered PET dynamic images to measure whole-tumor time activity curves. The method uses a two-compartment model to extract three component factors (vascular component, fast and slow component factors) from whole-tumor kinetics by model fitting. The kinetics in each pixel were expressed as a linear combination of the three factors. The three coefficients in the expression can be estimated by the linear least-square method and produce three factor images corresponding, respectively, to the permeability of the fast and the slow component factors and the plasma volume. Whole-tumor regions were separated into two regions-one with mainly fast kinetics that was evident in the fast factor images and one with slow kinetics that was evident in slow factor images. The two regions have markedly different uptake (0.036/spl plusmn/0.015 ml/min/g and 0.009/spl plusmn/0.006 ml/min/g for fast and slow kinetic sub-regions, respectively) and clearance rates (0.22/spl plusmn/0.15 /min and 0.023/spl plusmn/0.021 /min for fast and slow sub-regions, respectively). The overlap of the two resulting sub-regions is small (3.5/spl plusmn/1.7% of the two regions). Computer simulation and patient studies show that the method is robust for a wide range of noise levels. This method has combined the advantages of statistical factor analysis and the modeling approach.
Discrimination Procedures for Separate Families of Hypotheses

Abstract Procedures for discriminating between models from separate families of hypotheses are examined, with principal emphasis on procedures invariant under location and scale transformations. The discrimination procedures considered are compared using Monte Carlo samples as data for five pairs of invariant distributions. These comparisons are made with respect to the best invariant procedure, a procedure requiring no knowledge of sampling distributions, using approximate relative efficiencies calculated from the Monte Carlo results. On the basis of these efficiencies and the computational complexities of the procedures, suggestions are made for their use.
Hospital bath basins are frequently contaminated with multidrug-resistant human pathogens

The hospital environment is increasingly recognized as a reservoir for hospital-acquired pathogens. During a 44-month study period, a total of 1,103 basins from 88 hospitals in the United States and Canada were sampled. Overall, 62.2% of the basins (at least 1 basin at each hospital) were contaminated with commonly encountered hospital-acquired pathogens.
Playas and Lunettes on the Southern High Plains: Morphometric and Spatial Relationships

Abstract The surface of the Southern High Plains is dotted with thousands of small (<5 km2), circular, seasonally dry depressions, or playas, some of which are accompanied by a crescentic dune ridge, or lunette. The plays are inset into the sheets of eolian sediment that blanket the region (Blackwater Draw Formation) and the lunettes rest on the eolian mantle. Approximately 25,000 small playas, 1,100 of which have a lunette, were counted from all 540 topographic quadrangles covering the region (verified using data from soil surveys). Statistical analyses of the physical and spatial relationships of playas and lunettes were undertaken to better understand the origins and development of playas, and their relationship to lunettes. Data were collected from a subset of 40 topographic maps, digitized on a GIS, and analyzed using a nonparametric statistical procedure. Variation in texture of the Blackwater Draw Formation exerts considerable control on the distribution and size of playas. Playas are most numerous...
US and German Regulations of CO2 Emissions from Passenger Cars

Global air pollution, especially through the burning of fossil fuels, has reached a state of urgency that very soon will not be bearable anymore for the planet. CO2 emissions from passenger vehicles are a major contributing factor to this. A variety of regulations exist to control CO2 emissions, but nations do not share a common goal, a uniform standard. This paper seeks to give an insight into the problem of non-uniform environmental regulations throughout the world. Through the use of primary and secondary sources, it will provide a qualitative case study of CO2 emission regulations for passenger vehicles in Germany and the United States. In the context of an increasingly globalized world, policy recommendations, which will help in harmonizing regulations for all countries, are obtained. These recommendations include incorporating emission standards into the Transatlantic Trade and Investment Partnership, attaching a yet greater importance to environmental education and generating homogeneous standards within the automotive sector.
Individual Differences in the Effectiveness of Sexual Harassment Awareness Training1

Little research has investigated the effectiveness of sexual harassment awareness training videos on potential harassers' knowledge, behavior, or attitudes. A laboratory study was conducted that assessed the effects of a sexual harassment awareness training video on several training outcomes: sexual harassment knowledge, touching behavior, and attitudes associated with the likelihood of harassing others. Participants' propensity to harass was measured prior to their participation in the study. Results indicated that video-based training increased knowledge acquisition and reduced the inappropriate behavior of men who had a high propensity to harass. However, the training did not influence participants' long-term attitudes associated with the propensity to harass others. The research and practical implications of the study results are discussed.
Filling the Poverty Gap, Then and Now

The extent to which means-tested transfers, social insurance, and tax credits fill the gap between a family’s private resources and the poverty threshold is a periodic barometer of the social safety net. Using data on families from the Current Population Survey I examine how the level and composition of beforeand after-tax and after-transfer poverty gaps changed in response to changes in the policy and economic landscapes over the past two decades. The estimates presented here indicate not only dramatic changes in the level and sources of income maintenance programs filling the poverty gap, but also dramatic changes in which demographic groups successfully fill the gap. From the peak-to-peak business-cycle years of 1979 to 1999, the fraction of the gap left unfilled among non-elderly families in poverty has expanded by 25 percent, while the unfilled gap has increased by 50 percent among single female-headed families, families headed by non-whites, and families residing in the Northeast. In a given year the poor in the South fill considerably less of the poverty gap with cash welfare, but make up for much of the shortfall with higher payments of food stamps, SSI, and SSDI. Over time the poor in all regions of the country have substituted SSI, SSDI, and the EITC for cash welfare. Indeed, by 1999 the unfilled gap for families with related children present would be one-fifth larger without the EITC. With the exception of married-couple families, this apparent rate of replacement of disability payments and tax credits for cash welfare is less than one for one, leaving most poor families, especially non-white families and single female-headed families, financially more vulnerable today than in previous decades.
Soft-programmable bypass switch design for defect-tolerant arrays

Most wafer-scale processing arrays include bypass switches and wiring to permit signals to be routed around faulty modules. In some cases, the bypass circuitry contains registers to maintain data synchronization. The ideal switch design maximizes routing flexibility and switch yield while minimizing switch area and signal delay. Unfortunately these design goals work at cross-purposes. The goals also vary in importance, depending on the wafer architecture. For example, some architectures can cope with bypass logic failures, while others cannot. The ability to cope with failures may be a function of the failure mode. The author examines a number of bypass switch circuit and layout designs, and how well they meet to the design goals. He uses the DVLASIC distributed catastrophic fault yield simulator to perform yield computations. >
Learning by gradient descent in function space

The use of connectionist networks in which each node executes a different function to achieve efficient supervised learning is demonstrated. A modified backpropagation algorithm for such networks, which performs gradient descent in function space, is presented, and its advantages are discussed. The benefits of the suggested paradigm include faster learning and ease of interpretation of the trained network. The potential for combining this approach with other related approaches, including traditional backpropagation or reweighting is explored. >
Graphical algorithm for integration of genetic and biological data: proof of principle using psoriasis as a model

Motivation: Pathway analysis to reveal biological mechanisms for results from genetic association studies have great potential to better understand complex traits with major human disease impact. However, current approaches have not been optimized to maximize statistical power to identify enriched functions/pathways, especially when the genetic data derives from studies using platforms (e.g. Immunochip and Metabochip) customized to have pre-selected markers from previously identified top-rank loci. We present here a novel approach, called Minimum distance-based Enrichment Analysis for Genetic Association (MEAGA), with the potential to address both of these important concerns. Results: MEAGA performs enrichment analysis using graphical algorithms to identify sub-graphs among genes and measure their closeness in interaction database. It also incorporates a statistic summarizing the numbers and total distances of the sub-graphs, depicting the overlap between observed genetic signals and defined function/pathway gene-sets. MEAGA uses sampling technique to approximate empirical and multiple testing-corrected P-values. We show in simulation studies that MEAGA is more powerful compared to count-based strategies in identifying disease-associated functions/pathways, and the increase in power is influenced by the shortest distances among associated genes in the interactome. We applied MEAGA to the results of a meta-analysis of psoriasis using Immunochip datasets, and showed that associated genes are significantly enriched in immune-related functions and closer with each other in the protein–protein interaction network. Availability and implementation: http://genome.sph.umich.edu/wiki/MEAGA Contact: moc.liamg@neet.iost or ude.hcimu@olacnog Supplementary information: Supplementary data are available at Bioinformatics online.
Using Monodromy to Avoid High Precision in Homotopy Continuation

When solving polynomial systems with homotopy continuation, the fundamental numerical linear algebra computations become inaccurate when two paths are in close proximity. The current best defense against this ill-conditioning is the use of adaptive precision. While sufficiently high precision indeed overcomes any such loss of accuracy, high precision can be very expensive. In this article, we describe a simple heuristic rooted in monodromy that can be used to avoid the use of high precision.
Bridging the gaps between the histopathological and demographic risk factors of preterm birth in a unique Miami inner-city population.

We aim to identify the link between placental histological findings and obstetric reports to determine possible risk factors of spontaneous preterm birth (SPTB). We prospectively ascertained birth records and outcomes from all deliveries in our hospital in 1 year. Records were used to determine and stratify for either full-term or preterm [spontaneous or indicated (I)] deliveries. We analyzed for risk factor association using χ2 tests and common odds ratio estimates (SPSS v21.0). Our cohort totaled 6088 deliveries: 236 IPTB, 43 SPTB, and 5809 term births. Largely Hispanic, we determined race, parity, prenatal care access, preeclampsia, gestational diabetes, and BMI to be highly associated with SPTB (p < 0.01). Histologically, placentas of women with SPTB were twice as likely to have chronic villitis. We found that chronic villitis is associated with SPTB. Results of this study can be used in increasing the understanding of SPTB.
The Whig Tradition in America and Europe

In a liberal society such as prevailed in America during the Jeffersonian and Jacksonian eras, where the aristocracies, peasantries, and proletariats of Europe are missing, where virtually everyone, including the nascent industrial worker, has the mentality of an independent entrepreneur, two national impulses are bound to make themselves felt: the impulse toward democracy and the impulse toward capitalism. The mass of the people, in other words, are bound to be capitalistic, and capitalism, with its spirit disseminated widely, is bound to be democratic. This is one of the basic insights Tocqueville had about the actual behavior of the American people. The irony of early American history, however, is that these impulses, instead of supplementing each other, seemed to fight a tremendous political battle. The capitalist Whiggery of Hamilton was frightened of democracy, and the democratic tradition of Jackson, which was therefore able to destroy it, formulated a philosophy which seemed to deny its faith in capitalism. The result was a massive confusion in political thought, comparable to the one that we find in the constitutional era, and a set of victories and defeats which the Americans who experienced them scarcely understood. One is reminded of two boxers, swinging wildly, knocking each other down with accidental punches.Looked at from one point of view, it is strange that Federalism and neo-Federalism should have been shattered so badly in the liberal setting of American politics.
The promise and challenges of randomized controlled trials for surgical interventions.

At a number of panel discussions at scientific meetings over recent months, urologists have debated whether partial nephrectomy for renal cortical tumors confers a survival benefit over radical nephrectomy. Proponents of both views put forward intelligent, valid points but almost always came short of a conclusion. What has emerged from these discussions is an important question: Can data from retrospective analyses, with their inherent potential for selection bias, provide stronger evidence than that obtained from a randomized controlled trial closed prior to meeting the target accrual numbers? Randomized controlled clinical trials (RCTs) are powerful tools, generating the highest level of evidence to determine whether a cause-and-effect relationship exists between a health care intervention and a given outcome. However, the relevance and exactitude of an RCT’s findings are intimately tied to the rigor with which it is designed, executed, and analyzed. Undoubtedly, surgical RCTs are difficult to conduct. The challenges include:
The transforming growth factor beta signaling pathway is critical for the formation of CD4 T follicular helper cells and isotype-switched antibody responses in the lung mucosa

T follicular helper cells (Tfh) are crucial for the initiation and maintenance of germinal center (GC) reactions and high affinity, isotype-switched antibody responses. In this study, we demonstrate that direct TGF-β signaling to CD4 T cells is important for the formation of influenza-specific Tfh cells, GC reactions, and development of isotype-switched, flu-specific antibody responses. Early during infection, TGF-β signaling suppressed the expression of the high affinity IL-2 receptor α chain (CD25) on virus-specific CD4 T cells, which tempered IL-2 signaling and STAT5 and mammalian target of rapamycin (mTOR) activation in Tfh precursor CD4 T cells. Inhibition of mTOR allowed for the differentiation of Tfh cells in the absence of TGF-βR signaling, suggesting that TGF-β insulates Tfh progenitor cells from IL-2-delivered mTOR signals, thereby promoting Tfh differentiation during acute viral infection. These findings identify a new pathway critical for the generation of Tfh cells and humoral responses during respiratory viral infections.
Evaporitic mixed-water dolomitization on St. Croix, U.S.V.I.

ABSTRACT Dolomite exists in only a small area of Pliocene carbonates on St. Croix. This area consists of reef, lagoonal, and platform facies that underlie and rim the shoreline of Krause Lagoon, an embayment that existed on the southern coastline of St. Croix prior to industrial development in the 1960s. Since dolomite is not found in similar facies elsewhere on St. Croix, this geographic distribution suggests that the formation of the dolomite was related to hydrologic conditions in Krause Lagoon. The dolomite is calcium-rich (57-60 mol % Ca) and exists both as euhedral rhombs 2-75 µm in diameter and as a replacement mineral in dolomitized bioclasts. Bioclasts in the dolomitic strata often show good preservation of microstructure, particularly in large benthic forams and coralline algae The mean 87Sr/86Sr isotopic composition of the dolomite is 0.70887 ±0.00002 (2s, n = 3) which corresponds to the 87Sr/86Sr ratio of Late Miocene seawater. However, because the dolomite resides in Pliocene strata, it is difficult to invoke unmodified seawater as an agent of dolomitization. Dolomitization therefore requires a source of nonradiogenic strontium. Modern St. Croix groundwater has 87Sr/86Sr compositions between 0.7076 and 0.7085 (n = 4), well below the ratio of both modern seawater and the dolomites. Mixing calculations show that modern St. Croix groundwater could be a significant source of nonradiogenic strontium in a dolomite formed f om a two-component groundwater-seawater mix. On the basis of strontium-concentration modeling, the groundwater component responsible for the St. Croix dolomites may have ranged from 40% to 80% of the dolomitizing fluids. Stable isotopic values for the dolomite range from d18O of +0.7 to +3.8, and d13C of +0.6 to +2.4 (PDB), with increasing d18O and d13C values from the margins to the center of the lagoon. The maximum d18O values in these dolomites are too high to have formed fro unaltered groundwater or seawater, even accounting for ice-volume effects. Therefore the isotopically heaviest dolomite must have precipitated from fluids enriched in 18O, probably as a result of evaporation. Dolomitization from fluids produced from a mixture of evaporated seawater and St. Croix groundwater are consistent with the geochemistry and geologic distribution of the dolomite. Calculations show that such a scenario is possible, and may be fairly common, despite the relative complexity of the model. Documented block faulting of the Krause Lagoon area may have provided a stable hydrologic regime for a long enough time for dolomite to form, despite island uplift during the late Tertiary. Other models of dolomitization can be shown to be less likely or untenable on the basis of chemical, lithologic, or hydrologic criteria.
A cross-linguistic study of the processing of causative sentences

The comprehension of sentences expressing instigative causation (e.g., The horse makes the camel run) was investigated in children between the ages of 2;0 and 4;4, speaking English, Italian, Serbo-Croatian and Turkish. Crosslinguistic differences in development reveal the roles of morphological (causative particle, case inflection) and syntactic devices (periphrasis, word order) in guiding children’s processing of such constructions. It is suggested that local cues (inflectional suffixes, particles, specialized causative verb forms) contribute to the more rapid development of sentence processing strategies in Serbo-Croatian and Turkish. The word order systems of English and Italian, which require that the listener hold the entire sentence pattern in mind in order to determine underlying semantic relations, contribute to slower development on this task, Children’s comprehension of causative constructions was studied as one part of a large cross-linguistic investigation conducted in Berkeley, Rome, Dubrovnik and Istanbul (Aksu, 1978; Clancy, Jacobsen and Silva, 1976; Johnston and Slobin, 1977; Radulovic, 1975; Slobin, 1978; Slobin and Bever, 1978). Our overall concern is the effect of grammatical form on the developing ability to express basic concepts in language. The data consists of crosslinguistic differences in the rate and pattern of acquisition of the means for encoding notions of space, time, agency and causation.
Variable-rate predictive residual vector quantizer

A major problem with a VQ-based image compression scheme is its codebook search complexity. Recently, a predictive residual vector quantizer (PRVQ) was proposed by Rizvi and Nasrabadi (see IEEE Int. Conf. Image Processing, Austin, vol.1, p.608-612, Nov. 13-16, 1994). This scheme has a very low search complexity, and its performance is very close to that of the predictive vector quantizer (PVQ). The article presents a new VQ scheme called variable-rate PRVQ (VR-PRVQ), which is designed by imposing a constraint on the output entropy of the PRVQ. The proposed VR-PRVQ is found to give an excellent rate-distortion performance and clearly outperforms the state-of-the-art image compression algorithm developed by the Joint Photographic Experts Group (JPEG). >
Stability and Bifurcation Analysis of Oscillators With Piecewise-Linear Characteristics: A General Approach

A general approach is developed for determining the periodic solutions and their stability of nonlinear oscillators with piecewise-smooth characteristics. A modified harmonic balance/Fourier transform procedure is devised for the analysis. The procedure avoids certain numerical differentiation employed previously in determining the periodic solutions, therefore enhancing the reliability and efficiency of the method. Stability of the solutions is determined via perturbations of their state variables. The method is applied to a forced oscillator interacting with a stop of finite stiffness. Flip and fold bifurcations are found to occur. This led to the identification of parameter ranges in which chaotic response occurred.
Impact of central and peripheral TRPV1 and ROS levels on proinflammatory mediators and nociceptive behavior

Transient receptor potential vanilloid 1 (TRPV1) channels are important membrane sensors on peripheral nerve endings and on supportive non-neuronal synoviocytes in the knee joint. TRPV 1 ion channels respond with activation of calcium and sodium fluxes to pH, thermal, chemical, osmotic, mechanical and other stimuli abundant in inflamed joints. In the present study, the kaolin/carrageenan (k/c) induced knee joint arthritis model in rats, as well as primary and clonal human synoviocyte cultures were used to understand the reciprocal interactions between reactive nitroxidative species (ROS) and functional TRPV1 channels. ROS generation was monitored with ROS sensitive dyes using live cell imaging in vitro and in spinal tissue histology, as well as with measurement of ROS metabolites in culture media using HPLC. Functional responses in the experimental arthritis model, including increased nociceptive responses (thermal and mechanical hyperalgesia and allodynia), knee joint temperature reflecting local blood flow, and spinal cord ROS elevations were reduced by the ROS scavenger PBN after intraperitoneal pretreatment. Increases in TRPV1 and ROS, generated by synoviocytes in vitro, were reciprocally blocked by TRPV1 antagonists and the ROS scavenger. Further evidence is presented that synoviocyte responses to ROS and TRPV1 activation include increases in TNFα and COX-2, both measured as an indicator of the inflammation in vitro. The results demonstrate that contributions of ROS to pronociceptive responses and neurogenic inflammation are mediated both centrally and peripherally. Responses are mediated by TRPV1 locally in the knee joint by synoviocytes, as well as by ROS-induced sensitization in the spinal cord. These findings and those of others reported in the literature indicate reciprocal interactions between TRPV1 and ROS play critical roles in the pathological and nociceptive responses active during arthritic inflammation.
Random evolutionary time-scale decomposition in robust control of jump linear systems

This paper addresses the issues of model simplification, decomposition, and design of robust reduced-order controllers in the context of piecewise-deterministic systems exhibiting distinguishable slow and fast modes in their form systems. The random jumps from one structure to another at random points in time are governed by a finite state Markov chain, and between two consecutive jumps the system admits a linear structure with open-loop slow and fast modes, where the dynamics are driven by not only a (state-feedback) control but also an unknown disturbance. Optimum slow and composite controllers are derived in the mathematical framework of H/sup /spl infin// control (adapted to such hybrid systems), and their respective performances are evaluated. The theoretical results are then applied to a numerical example involving the robust control of a planar elbow manipulator with remotely driven links.
Thermal and Electrical Transport Properties of Spark Plasma-Sintered HfB2 and ZrB2 Ceramics

The thermal and electrical transport properties of various spark plasma-sintered HfB2- and ZrB2-based polycrystalline ceramics were investigated experimentally over the 298–700 K temperature range. Measurements of thermal diffusivity, electrical resistivity, and Hall coefficient are reported, as well as the derived properties of thermal conductivity, charge carrier density, and charge carrier mobility. Hall coefficients were negative confirming electrons as the dominant charge carrier, with carrier densities and mobilities in the 3–5 × 1021 cm−3 and 100–250 cm2·(V·s)−1 ranges, respectively. Electrical resistivities were lower, and temperature coefficients of resistivity higher, than those typically reported for HfB2 and ZrB2 materials manufactured by the conventional hot pressing. A Wiedemann–Franz analysis confirms the dominance of electronic contributions to heat transport. The thermal conductivity was found to decrease with increasing temperature for all materials. Results are discussed in terms of sample morphology and compared with data previously reported in the scientific literature.
Tritium-Helium Effects in Metals

Investigations of helium effects in metals at the Savannah River Laboratory have been carried out by introducing helium by radioactive decay of tritium. This process does not create concurrent radiation damage, such as accompanies ion implantation and (n,..cap alpha..) reactions. The process has its own peculiarities, however, which partially mask and interact with the helium effect of interest. The distribution and local concentration of helium and tritium, which are responsible for changes in mechanical properties and fracture mode, are controlled by the large difference in solubility and diffusivity between the two atoms and by their differing interaction energies with lattice defects, impurities, and internal boundaries. Furthermore, in all investigations with helium generated from tritium decay, some tritium and deuterium are always present. Consequently, property changes include tritium-helium interaction effects to some extent. Results of investigations with several austenitic stainless steels, Armco iron, and niobium single crystals illustrate the variety of phenomena and some of the complex interactions that can be encountered.
Stochastic Models of Internal Mail Delivery Systems

This paper develops two stochastic models of an internal mail delivery system in which a single clerk picks up, sorts and delivers mail to a closed loop of offices. The two models differ in whether deliveries are made at scheduled times or not. For a model in which all mail picked up each round is sorted before the next delivery, we assume that mail is generated in the system by a stationary Poisson process and derive an expression for the expected delay between generation of a letter and its ultimate delivery. These results are then extended to systems in which letters are generated according to a stationary compound Poisson process and to multiple clerk delivery systems. A second model in which mail is delivered at scheduled times only is shown to be equivalent to a classical storage process. For this model, we derive bounds on the expected number of letters left unsorted at the start of a scheduled delivery and the expected delivery delay. This model is also generalized to multiclerk systems.
A Key-based Adaptive Transactional Memory Executor

Software transactional memory systems enable a programmer to easily write concurrent data structures such as lists, trees, hashtables, and graphs, where non-conflicting operations proceed in parallel. Many of these structures take the abstract form of a dictionary, in which each transaction is associated with a search key. By regrouping transactions based on their keys, one may improve locality and reduce conflicts among parallel transactions. In this paper, we present an executor that partitions transactions among available processors. Our key-based adaptive partitioning monitors incoming transactions, estimates the probability distribution of their keys, and adaptively determines the (usually nonuniform) partitions. By comparing the adaptive partitioning with uniform partitioning and round-robin keyless partitioning on a 16-processor SunFire 6800 machine, we demonstrate that key-based adaptive partitioning significantly improves the throughput of finegrained parallel operations on concurrent data structures.
Toxicity and Residual Activity of Methoxyfenozide and Tebufenozide to Codling Moth (Lepidoptera: Tortricidae) and Oriental Fruit Moth (Lepidoptera: Tortricidae)

A series of studies were conducted to examine the residual activity and toxicity of the ecdysone agonists tebufenozide and methoxyfenozide to codling moth, Cydia pomonella (L.), and oriental fruit moth, Grapholita molesta (Busck), in North Carolina apple systems. Methoxyfenozide exhibited greater activity than tebufenozide against codling moth eggs in dose-response bioassays, with a 4.5- and 5.3-fold lower LC50 value to eggs laid on fruit treated before or after oviposition, respectively. Oriental fruit moth eggs were 57- and 12-fold less sensitive to methoxyfenozide than were codling moth eggs on fruit treated before and after oviposition, respectively. Methoxyfenozide was effective in reducing larval entries of both codling moth and oriental fruit moth in field residual activity bioassays, exhibiting activity for at least 28 d after application. Residue breakdown on fruit was ≈80% at 28 d after treatment for both methoxyfenozide and tebufenozide, with the most rapid residue decline (60%) occurring during the first 14 d after application. Two applications of methoxyfenozide applied at 14-d intervals provided better canopy coverage and higher residue levels than one application. Spray volume (683 versus 2,057 liters/ha) did not affect the efficacy of methoxyfenozide. Leaf and fruit expansion during the season was measured to determine potential plant-growth dilution effects on residual activity. There was very little increase in leaf area after mid May, but increase in fruit surface area over the season was described by a second order polynomial regression. Implications for codling moth and oriental fruit moth management programs are discussed.
Effect of Substratum Morphology on Animal Cell Adhesion and Behavior

Glass surfaces with well defined surface morphologies have been prepared using photolithography to study the effect of surface morphology on cell adhesion and function. Using a transformed recombinant cell-line, AtT-20, as a model of shear sensitive cell, we have shown that cell-substratum adhesion strength is enhanced using a surface with uniform grooves without any loss in cellular function. Furthermore, using primary hepatocytes as a model for a cell whose function is sensitive to its shape, we have shown that surface morphology can modulate cell shape as well as its function.
Solving a Jules Verne Cryptogram

To save the life of an innocent man, a secret message must be deciphered; Jules Verne provides an original technique
Financial Record Checking in Surveys: Do Prompts Improve Data Quality?.

Self-reports of financial information in surveys, such as wealth, income, and assets, are particularly prone to inaccuracy. We sought to improve the quality of financial information captured in a survey conducted by phone and in person by encouraging respondents to check records when reporting on income and assets. We investigated whether suggestive prompts influenced unit response, compliance with the request to check records, precision of estimates, and accuracy. We conducted a split sample experiment in the Community Advantage Panel Survey in which half of telephone respondents and half of in-person household interview respondents were encouraged to check the records. We found a modest positive effect of prompts on compliance but no effect on unit response, precision, or accuracy.
Pipestone’s True Grit: Observations from Experimental Pipe-Making

Experimental archaeology is a productive way to understand pipes as one part of a technological system. In this study, a comparative set of pipe-making tools was made to aid in the identification of such tools in archaeological assemblages from the Great Plains. In order to replicate pipe manufacturing processes, stone tools were flintknapped out of Florence chert, heat-treated Florence chert, Smoky Hill jasper, Peoria chert, and Alibates agatized dolomite. These tools were used to scrape, cut, gouge, ream, and drill two types of pipestone (Kansas pipestone and Minnesota pipestone) and a hematite nodule. The process of working stone tools on pipestone led to three important observations. First, these actions created diagnostic use-wear and residue that were identifiable at low-power magnification (<100×). Second, there were observable differences in the Kansas pipestone, Minnesota pipestone, and hematite. The texture of the Kansas pipestone was grittier than the Minnesota pipestone and this resulted in a grainier powder and more microscopic striations on the tools. Additionally, pipestone and hematite residues were distinguishable at a microscopic level based on differences in color and texture. Third, pipestone powder was the major by-product of pipe manufacturing activities and is thus important to look for in the archaeological record. Orienting pipe manufacture within a larger framework of technological organization provides a better foundation for interpreting their position within past societies.