cssi/SciSciGPT-SciSciNet huggingface dataset:
Remarks on Problem B-3 on the 1990 William Lowell Putnam Mathematical Competition

conditions (1) and (2). While it is beyond what students could reasonably be expected to solve during the exam, clearly the elegant question is: What is the maximum order of a subset S c U in which no two elements commute? We shall show that this order is 32,390, so that any subset of 32,391 matrices in U must include a commuting pair. The method we use can be applied to numerous variations of the problem posed. For our purposes, the requirement of perfect square entries creates an extra level of difficulty. Consequently, let us first solve a variation that seems more natural. We shall then return to the original question of finding the largest totally noncommuting set S when the entries must be perfect squares. Specifically, we ask what is the order of a maximum noncommuting set among all 2 X 2 matrices (a b) with nonnegative integer entries bounded by 0 < a, b, c, d < n. In this case our universal set U has (n + 1)4 matrices in it.
Stability and Ring-Shift Tautomerization of Cyclic Anhydrides of Benzenehexasulfonic Acid

Upon heating in a dry atmosphere, benzenehexasulfonic acid forms three cyclic anhydrides. Mono- and dianhydride do not hydrolyze readily due their flatter structures compared to the hydrolysis products. The trianhydride appears more to be reactive toward hydrolysis. In solutions, the mono- and dianhydride undergo ring-shift tautomerization, which is in the latter case shifted toward the para isomer.
Racemic 5-ethyl-2,6-dimethyl-4-p-tolyl-3-cyclohexenecarboxylic acid: anRSdimer

The title compound, C18H24O2, was synthesized to study the inter­action of the two enanti­omers in the solid state. The resultant racemate is made up of carboxylic acid RS mol­ecules which are dimerized through their carboxyl groups by O—H⋯O hydrogen bonds, forming R22(8) rings. The dimers are inter­connected via weak C—H⋯π(arene) inter­actions, resulting in thick two-dimensional layers.
Theoretical studies on the isomerization and dissociation of the acrolein ions

Abstract Nine isomers of the acrolein ion (C 3 H 4 O + ) and the relevant transition states connecting them were calculated at HF/6-31G ∗ and B3LYP/6-31G ∗ levels. The nine dissociation channels, C 2 H 4 + (+CO), C 3 H 3 O + (+H ), HCO + (+C 2 H 3 ), H 2 CO + (+C 2 H 2 ), C 2 H 3 + (+HCO ), HCOH + (+C 2 H 2 ), C 2 H 2 + (+H 2 CO), CO + (+C 2 H 4 ), and C 2 H 2 + (+HCOH), were studied and the transition states to all product channels were found. The lowest energy dissociation path to CO loss involves a distonic ion, CH 2 CH 2 CO + , and the methylketene ion, CH 3 CHCO + the latter being the most stable C 3 H 4 O + isomer. The heats of formation of the C 3 H 4 O + isomers are obtained based on the known heats of formation of C 2 H 4 + and CO and the calculated relative energies.
An integer optimization problem with mixed algebraic and number-theoretic constraints

Two problems dealing with theory of numbers are considered. First, an unusual integer optimization problem characterized by mixed algebraic and number-theoretic constraints is studied, which has application in the sharing of secrets or sensitive resources. Next, a linear difference algorithm is proposed for generating sequences of prime numbers with accelerated growth rate in the number of digits produced.
Experimental and Theoretical Studies of MCF3+ (M = Fe and Co): Reactivities, Structures, and Potential Energy Surface for C−F Activation

The gas-phase reactions of FeCF3+ and CoCF3+ with a series of small alkanes and alkenes were studied by Fourier transform ion cyclotron resonance (FTICR) mass spectrometry. These ions, which are generated from the reactions of the bare metal ions with CF3I, both react with alkanes larger than ethane and with small alkenes primarily by CF2 displacement reactions. Hydride abstraction is also observed in some cases. Collision-induced dissociation and ion−molecule reactions indicate that the structure of MCF3+ ( M = Fe, Co) is an ion−dipole complex, FM+···F2C, involving C−F activation. A good fit of pseudo-first-order kinetics is obtained for the reactions of FeCF3+ and CoCF3+ with the above selected hydrocarbons. The reaction rates of FeCF3+ and CoCF3+ with the alkanes increase dramatically with the length of the alkane chain. The C−F activation mechanism of Fe+ or Co+ with the CF3 ligand was also investigated theoretically. The potential energy surface (PES) of the [Fe, C, F3]+ system and the local minima o...
A simulation study on the performance of bounded length confidence intervals for quantiles with censored data

Gardiner, Susarla and van Ryzin (1988) considered the problem of constructing confidence intervals of prescribed accuracy (width ≤= 2d, d > 0) and given coverage probability (l-2α, α e(0, 1/2)) for quantiles of a distribution function based on censored data. In a subsequent paper they obtained bounds on the error between this coverage probability and 1-2α as d shrinks to zero. The purpose of the presentation here is to examine the behavior of the confidence interval estimation procedure in simulations for moderate values of d, for varying amounts of censoring and different survival distributions.
Selective extraction of oxygenates from savory and peppermint using subcritical water

The yields of oxygenated and non-oxygenated flavour and fragrance compounds from savory (Satureja hortensis) and peppermint (Mentha piperita) were compared using subcritical water extraction, supercritical carbon dioxide extraction (SFE) and hydrodistillation. Extraction rates with subcritical water increased with temperature (100–175 °C), but some desired organics (linalool and γ-terpinene) showed substantial degradation at temperatures >150 °C. However, subcritical water did not expose extracted compounds to atmospheric oxygen (as occurs in hydrodistillation) and thus may avoid the degradation of compounds like thymoquinone. Extraction of savory with subcritical water at 100 °C for 40 min gave ca. 100% recoveries (compared to hydrodistillation) for thymol and carvacrol, and >150% recoveries of borneol and linalool. Recoveries with 60 min of SFE (pure CO2 at 400 bar and 50 °C) were similar to hydrodistillation for borneol and linalool, but only ca. 50% for thymol and carvacrol. For peppermint, 30 min (at 150 °C) or 12 min (at 175 °C) of subcritical water extraction and 1 h of SFE gave good quantitative agreement with 4 h of hydrodistillation for carvone, pulegone, piperitone, eucalyptol, menthone, neomenthol and menthol, but the short subcritical water extractions only recovered ca. 40% of the less polar menthyl acetate. Subcritical water preferentially extracts more polar (oxygenated) flavour compounds, and ca. 80% extraction of oxygenated flavour compounds could be achieved under conditions which only extracted ca. 10–15% of the monoterpenes and <5% of the sesquiterpenes. In contrast, SFE had the lowest degree of selectivity and SFE extracts included plant alkane waxes as well as the same flavour compounds recovered by hydrodistillation. Copyright © 2001 John Wiley & Sons, Ltd.
STUDIES IN RODENT POLIOMYELITIS : IV. THE PATHOLOGY OF MURINE AND CAVIAN POLIOMYELITIS.

A description has been given of the lesions produced in mice and guinea pigs by inoculation of the Jungeblut-Sanders virus. The histopathological findings, although in themselves not conclusive, would tend to support the opinion that Jungeblut and Sanders have transmitted the SK poliomyelitis virus to mouse and guinea pig. In mice the virus apparently retains its affinity for the anterior horns of the spinal cord, but in a moderate degree. Associated with a marked increase in virulence of the virus, a strong affinity for the cerebral tissues, more particularly the olfactory centers, develops. On transmitting this murine variant of the virus to guinea pigs, however, the original character of the virus is again revealed. There is a reversion to a predominant affinity for the nerve cells of the anterior horns of the spinal cord.
Prenatal Cocaine Exposure and Adolescent Neural Responses to Appetitive and Stressful Stimuli

Preclinical research has demonstrated the effects of prenatal cocaine exposure (PCE) on brain regions involved in emotional regulation, motivational control, and addiction vulnerability—eg, the ventral striatum (VS), anterior cingulate (ACC), and prefrontal cortex (PFC). However, little is known about the function of these regions in human adolescents with PCE. Twenty-two adolescents with PCE and 22 age-, gender-, and IQ-matched non-cocaine exposed (NCE) adolescents underwent functional magnetic resonance imaging (fMRI) during exposure to individually personalized neutral/relaxing, stressful, and favorite-food cues. fMRI data were compared using group-level two-tailed t-tests in the BioImage Suite. In comparison with NCE adolescents, PCE adolescents had reduced activity within cortical and subcortical brain regions, including the VS, ACC, and medial and dorslolateral PFC during exposure to favorite-food cues but did not differ in neural responses to stress cues. Subjective food craving was inversely related to dorsolateral PFC activation among PCE adolescents. Among PCE adolescents, subjective anxiety ratings correlated inversely with activations in the orbitofrontal cortex and brainstem during the stress condition and with ACC, dorsolateral PFC, and hippocampus activity during the neutral–relaxing condition. Thus adolescents with PCE display hypoactivation of brain regions involved in appetitive processing, with subjective intensities of craving and anxiety correlating inversely with extent of activation. These findings suggest possible mechanisms by which PCE might predispose to the development of addictions and related disorders, eg, substance-use disorders and binge-eating.
2,4-Diaminothieno[2,3-d]pyrimidine lipophilic antifolates as inhibitors of Pneumocystis carinii and Toxoplasma gondii dihydrofolate reductase.

Ten previously unreported 2,4-diaminothieno[2,3-d]pyrimidine lipophilic dihydrofolate reductase inhibitors were synthesized as potential inhibitors of Pneumocystis carinii and Toxoplasma gondii dih...
Children's perceptions of divorce

Abstract The ways in which children perceive and respond to parental divorce vary by age, gender, level of parental conflict, caretaking arrangements, individual personality and resilience, availability of support networks, and, of special concern here, their level of cognitive development. Piagetian theory necessarily serves as the underpinning of the discussion, which is amplified by research. The importance of professionals being aware of the impact of cognitive maturity on children's perceptions and consequent responses is stressed in the conclusion.
1-Soliton solution of 1 + 2 dimensional nonlinear Schrödinger’s equation in power law media

Abstract This paper obtains the 1-soliton solution of the nonlinear Schrodinger’s equation in 1 + 2 dimensions for parabolic law nonlinearity. An exact soliton solution is obtained in closed form by the solitary wave ansatze.
Evolutionary stability in the asymmetric war of attrition.

Abstract It is shown that there are at least two evolutionarily stable strategies, or ESSs, in the war of attrition with a role asymmetry when players make an error with a small but positive probability in implementing their strategy choices. This result proves Maynard Smith's original conjecture that players should choose asymmetric pure strategies in the asymmetric war of attrition. It is also in contrast to the standard nonexistence result of an ESS in this game under complete information. To derive this result we discretize the original game and apply the limit ESS condition introduced by Selten. The result is also compared with other evolutionary analyses of this game.
Enantiotopic differentiation during the biotransformation of valproic acid to the hepatotoxic olefin 2-n-propyl-4-pentenoic acid.

The enantiomers of 2-[( 3-13C]-n-propyl)pentanoic acid [(R)- and (S)-[13C]VPA] were employed as metabolic probes to investigate stereochemical aspects of the biotransformation of valproic acid (VPA) to 2-n-propyl-4-pentenoic acid (delta 4-VPA), a hepatotoxic metabolite of VPA. When incubated with hepatocytes freshly isolated from untreated male rats, each labeled substrate (initial concentration 1.0 mM) underwent metabolism to [13C]-delta 4-VPA, the formation of which was time-dependent and occurred at a rate of ca. 20 ng/(10(6) cells.4-h incubation). Analysis of this unsaturated metabolite by GC-MS techniques revealed that, following incubation of (R)-[13C]VPA, desaturation had taken place preferentially (by a factor of approximately 4) on the labeled propyl group (i.e., on the R side chain). Parallel incubations with (S)-[13C]VPA supported this conclusion, in that metabolism of this isotopic variant of VPA led to a terminal olefin that also was predominantly (83 +/- 2%) of R configuration (in this case oxidized selectively on the unlabeled side chain). Hence, biotransformation of VPA to delta 4-VPA in rat hepatocytes occurs with marked enantiotopic differentiation, favoring production of the R enantiomer of this chiral metabolite. When rats were pretreated with phenobarbital (80 mg kg-1 day-1 ip for 3 days) prior to isolation of hepatocytes, the overall rate of metabolism of VPA to delta 4-VPA over the 4-h incubation period increased approximately 3-fold, while the degree of product enantioselectivity was unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)
High-pressure liquid chromatography of steroids

After a brief discussion of the merits and limitations of high-pressure liquid chromatography (HPLC) relative to other chromatographic methods, special problems in the application to steroids are discussed. Publications on HPLC of steroids are then discussed under the headings of individual classes, arranged generally in the order of increasing polarity.
Injuries to children in the United States related to trampolines, 1990-1995: a national epidemic

Study Objective. To describe the epidemiology of trampoline-related injuries among children in the United States. Design. A retrospective analysis of data for children 18 years old and younger from the National Electronic Injury Surveillance System of the United States Consumer Product Safety Commission for 1990 through 1995. Results. There were an estimated 249 400 trampoline-related injuries [95% confidence interval (CI), 166 300–332 500] to children 18 years old and younger treated in hospital emergency departments in the United States during the 6-year study period. The number of injuries increased by 98% from 29 600 in 1990 to 58 400 in 1995, with an average of 41 600 (95% CI, 27 700–55 500) injuries per year, or 59.4 injuries per 100 000 United States children per year (95% CI, 39.6–79.3). The median age of injured children was 10 years, and 50% were males. Ninety-three percent of injuries occurred at home. Injuries to the extremities predominated among children of all ages and accounted for more than 70% of all injuries. This study identified several age-specific injury patterns. There was an inverse relationship between age versus the relative frequency of upper extremity injuries, and fractures and dislocations; and there was a direct relationship between age versus lower extremity injuries and soft tissue injury. There was also an inverse relationship between age versus facial injuries, head and neck injuries, and lacerations. Annually, an estimated 1400 children (95% CI, 800–2000), or 2.0 per 100 000 United States children (95% CI, 1.1–2.9), required hospital admission or interhospital transfer because of a trampoline-related injury. This represented 3.3% of all children with a trampoline-associated injury. Fractures or dislocations accounted for 83% of injuries among admitted or transferred children, and children with a fracture or dislocation were more likely to be admitted or transferred to another hospital (8.4%) than children with other types of injury (relative risk, 10.80; 95% CI, 9.40 Conclusion. Injuries related to trampolines, especially backyard trampolines, are an important cause of pediatric morbidity. These injuries have also resulted in death. The rapid increase in the number of trampoline-related injuries to children during recent years is evidence that current prevention strategies are inadequate. Children should not use trampolines at home, and the sale of trampolines for private recreational use should be stopped.
Flight boundary layer transition measurements on a slender cone at Mach 20

Experimental flight boundary layer transition data have been obtained on a 3.962-m-long, 5 deg half-angle cone with an initial nose radius of 0.254 cm. The data were obtained during re-entry from altitudes of approximately 30.480 to 18.288 km at a free-stream Mach number of 20. The free-stream Reynolds number varied from 6.56 x 10 to the 6th/m to 52.5 x 10 to the 6th/m, and the total enthalpy from about 18.3 to 16.9 MJ/kg. The locations of the beginning and end of transition were determined by the intersection of curves faired throug the laminar, transitional, and turbulent heating-rate data. The temperature-history technique for determining transition as currently used (sharp break in curve) was shown to compare unfavorably with the heating-rate-distribution method. The heating-rate-history technique, which is proportional to the temperature derivative and consequently more sensitive to perturbations, gives better agreement with the heating-rate distribution transition results.
Prefix Computation on a Faulty Hypercube

The fundamental question addressed in this paper is that of computing the parallel prefix operation. In particular, we study the problem of performing such an operation in an n-dimensional SIMD hypercube, Q_n, with up to n-1 node faults. In an SIMD hypercube, during a communication step, nodes can exchange information with their neighbors only across a specific dimension. We exhibit an n+5 logn algorithm for this problem. The development of the algorithm is based on the existence of two so-called free dimensions in such a faulty hypercube [6].
A model for dual-channel high electron mobility transistors

Abstract In this paper, a technique is developed to calculate the total charge of a dual channel HEMT. This technique is able to successfully predict the gradual saturation of charges in the device. The current voltage characteristics and the transconductance of the device are derived including the effect of channel length modulation as well as parasitic source and drain resistances. The theoretical predictions of the model are compared with experimental data and shown to be in good agreement.
A comparison of the gametogenic cycle between the Pacific oyster Crassostrea gigas and the Suminoe oyster Crassostrea rivularis in Washington State

Abstract The gamotogenic cycle of the Suminoe oyster, Crassostrea rivularis , was compared with that of two groups of Pacific oysters ( Crassostrea gigas ) on an intertidal oyster bed in Oakland Bay, Washington. The Pacific oysters exhibited an earlier and more extensive development of gonad relative to C. rivularis . Resulting carbohydrate depletion was much greater in C. gigas relative to C. rivularis . Both groups of Pacific oysters spawned completely in mid-August. C. rivularis did not spawn but, rather, initiated phagocytosis of gametes by leucocytes. The implications of the results on the development of a marketable “summer” oyster are discussed.
Experiments, contingencies, and curriculum: Providing opportunities for learning through improvisation in science teaching

In this article, we examine how, through discourse processes, a third grade teacher and her students come to situationally define science in their classroom. The teacher's use of particular discursive strategies promoted student talk, thus providing opportunities for students to learn about science through the exploration of a set of anomalous results in a life science experiment. Drawing from social studies of science, we used a discourse analytical approach to examine the classroom members' logic of experimentation, their explanations and scientific decisions, and their accounts of the events. These analyses allowed us to identify how particular teaching strategies afforded students opportunities to learn science concepts and about scientific processes. © 2000 John Wiley & Sons, Inc. Sci Ed84:624–657, 2000.
Current Stem Cell Delivery Methods for Myocardial Repair

Heart failure commonly results from an irreparable damage due to cardiovascular diseases (CVDs), the leading cause of morbidity and mortality in the United States. In recent years, the rapid advancements in stem cell research have garnered much praise for paving the way to novel therapies in reversing myocardial injuries. Cell types currently investigated for cellular delivery include embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), and adult stem cell lineages such as skeletal myoblasts, bone-marrow-derived stem cells (BMSCs), mesenchymal stem cells (MSCs), and cardiac stem cells (CSCs). To engraft these cells into patients' damaged myocardium, a variety of approaches (intramyocardial, transendocardial, transcoronary, venous, intravenous, intracoronary artery and retrograde venous administrations and bioengineered tissue transplantation) have been developed and explored. In this paper, we will discuss the pros and cons of these delivery modalities, the current state of their therapeutic potentials, and a multifaceted evaluation of their reported clinical feasibility, safety, and efficacy. While the issues of optimal delivery approach, the best progenitor stem cell type, the most effective dose, and timing of administration remain to be addressed, we are highly optimistic that stem cell therapy will provide a clinically viable option for myocardial regeneration.
3D visualization techniques to support slicing-based program comprehension

Graphic visuals derived from reverse engineered source code have long been recognized for their impact on improving the comprehensibility of structural and behavioral aspects of large software systems and their source code. A number of visualization techniques, primarily graph-based, do not scale. Some other proposed techniques based on 3D metaphors tend to obscure important structural relationships in the program. Multiple views displayed in overlapping windows are suggested as a possible solution, which more often than not results in problems of information overload and cognitive discontinuity. In this paper, we first present a comprehensive survey of related work in program comprehension and software visualization, and follow it up with a detailed description of our research which uses program slicing for deriving program structure-based attributes and 3D-metaball-based rendering techniques to help visualization-based analysis of source code structure. Metaballs, a 3D modeling technique, has already found extensive use for representing complex organic shapes and structural relationships in biology and chemistry. We have developed a metaball software visualization system in Java3D, named MetaViz. As proof of concept, using MetaViz, we demonstrate the creation of 3D visuals that are intuitively comprehensible and communicate information about relative component complexity and coupling among components and therefore enhance comprehension of the program structure.
Exchange coupling and conduction-electron polarization in metals. II

The effect on the isotropic spin density of the (k,k\ensuremath{'}) dependence of the exchange coupling $J(\mathbf{k},{\mathbf{k}}^{\ensuremath{'}})$ between a localized magnetic moment and conduction electrons predicted by Ruderman-Kittel-Kasuya-Yosida (RKKY) theory is determined quantitatively. Spherical local moments are employed, viz., $\mathrm{Gd}(4{f}^{7})$ and $\mathrm{Fe}(3{d}^{5})$ (which are taken as representative of rare-earth and transition metal moments, respectively). The conduction bands are described by simple orthogonalized plane waves appropriate to a "free-electron" metal with k the wave vector of the incident electron and k\ensuremath{'} that of the scattered electron. We find that a $Q$-dependent coupling (where $Q\ensuremath{\equiv}|\mathbf{k}\ensuremath{-}{\mathbf{k}}^{\ensuremath{'}}|$) has some justification when dealing with a Gd local moment but has considerably less justification for Fe. Both the (k,k\ensuremath{'}) and the $Q$-coupling schemes yield a "main" spindensity peak which is more diffuse than that yielded by coupling approximations traditionally applied to RKKY theory. Spin-density results were obtained which are appropriate to the outer reaches of a lattice site and to the nuclear site of either the local moment or neighboring atoms (these involve inclusion of core $s$ terms in the spin density). These results suggest that spin distributions obtained by neutron diffraction and those inferred from hyperfine field measurements may differ significantly.
Perspectives on Localized Corrosion in Thin Layers of Particulate

The requirements for the initiation and propagation of localized corrosion are reviewed, and the stability criteria for sustained localized corrosion are discussed. A conceptual framework is applied to a specific scenario of a hot metal surface covered by a thin layer of particulate containing dissolvable salts in the presence of air of limited humidity. A number of processes are demonstrated to affect the crevice corrosion propagation, stifling and arrest. Contributions of the particulate layer properties, the anode, cathode and coupled processes are identified, showing that any of these can control localized corrosion propagation. The findings add to the technical basis for the analysis of localized corrosion by a decision tree methodology.
Synthesis of early RNA in bacteriophage T4-infected Escherichia coli B.

A T4-specific protein is required for the initiation, in vivo, of a second early class of RNA that differs from that formed immediately after infection.
Brain ontogeny and life history in Homo erectus.

Coqueugniot et al.’s (2004) recent study of the Mojokerto fossil (Perning 1), an important juvenile Homo erectus specimen from Indonesia, provides valuable insights into the evolution of human ontogeny, life history, and cognition. These authors used computed tomography to study the subarcuate fossa and the bregmatic region in Mojokerto, modern humans, and chimpanzees (Pan troglodytes). These analyses enabled assessment of the age at death and endocranial volume (EV) in the fossil, which suggested that the Mojokerto juvenile died at about one year of age (range: 0.5e1.5 years, and possibly younger) and had an endocranial volume of about 663 cc. Coqueugniot et al. used these estimates to investigate agerelated changes in proportional endocranial volume in H. erectus. Specifically, they calculated proportional EVs by dividing each juvenile’s EV by average adult EV within each species. Mojokerto’s proportional EV was measured at 72e84% of adult volume, indicating that the fossil fell into the range for one-year-old chimpanzees, but possibly above the range for comparably aged Homo sapiens. Based on these results, Coqueugniot et al. proposed that, like some primates, H. erectus gave birth to offspring with proportionately large brains. The authors argued that this result suggests restricted postnatal brain growth in H. erectus, and possibly the absence of secondary altriciality. They also suggested that H. erectus brains matured soon after birth, constraining the development of language and cognitive skills. Despite the high quality and innovative design of Coqueugniot et al.’s study, their analyses leave several important
Design of a GaInP/GaAs tandem solar cell for maximum daily, monthly, and yearly energy output

Solar concentrator cells are typically designed for maximum efficiency under the AM1.5d standard spectrum. While this methodology does allow for a direct comparison of cells produced by various laboratories, it does not guarantee maximum daily, monthly, or yearly energy production, as the relative distribution of spectral energy changes throughout the day and year. It has been suggested that achieving this goal requires designing under a nonstandard spectrum. In this work, a GaInP/GaAs tandem solar cell is designed for maximum energy production by optimizing for a set of geographically-dependent solar spectra using detailed numerical models. The optimization procedure focuses on finding the best combination of GaInP bandgap and GaInP and GaAs sub-cell absorber layer thicknesses. It is shown that optimizing for the AM1.5d standard spectrum produces nearly maximum yearly energy. This result simplifies the design of a dual-junction device considerably, is independent of the optical concentration up to at least 500 suns, and holds for a wide range of geographic locations. The simulation results are compared to those obtained using a more traditional, ideal-diode model.
Evaluation of uncertainties associated with geocoding techniques

Spatial databases contain geocoded data. Geocoded data plays a key role in many engineering applications such as transportation and environmental studies where geospatial information systems (GIS) are used for spatial modeling and analysis as they contain spatial information (latitude and longitude) about objects. The information that a GIS produces is impacted by the quality of the geocoded data (coordinates) stored in its database. To make appropriate and reasonable decisions using geocoded data, it is important to understand the sources of uncertainty in geocoding. There are 2 major sources of uncertainty in geocoding, 1 related to the database that is used as a reference data set to geocode objects and 1 related to the interpolation technique used. Factors such as completeness, correctness, consistency, currency, and accuracy of the data in the reference database contribute to the uncertainty of the former whereas the specific logic and assumptions used in an interpolation technique contribute to the latter. The main aim of this paper is to understand uncertainties associated with interpolation techniques used for geocoding. In doing so, 3 geocoding algorithms were used and tested and the results were compared with the data collected by the Global Positioning System (GPS). The result of the overall comparison indicated no significant differences between the 3 algorithms.
Regenerative pulse-shaping techniques and their applications on the amplification of sub-20 fs or two-color femtosecond pulses

Summary form only given. In summary, we have successfully demonstrated a variety of methods to dramatically increase the bandwidth of Ti:sapphire chirped-pulse laser amplification systems. These methods have been used to generate amplified pulses as short as 18 fs. Additionally, we have simultaneously amplified and compressed two femtosecond pulses separated by as much as 100 nm in wavelength.
Cultural Dimensions Reconsidered: Global and Regional Analyses of the Ethnographic Atlas

Developments in ethnographic data compilation over the past decade provide the basis for a new and extended study of the dimensions of culture. The approach taken in the current research was to apply various multivariate statistical analyses for the purpose of revealing the dimensions by which culture traits tend to be associated. Based on Murdock's Ethnographic Atlas, 65 cultural traits were coded, scaled, and intercorrelated over a sample of 863 societies. Intercorrelations were also computed between traits for each of six regional subsamples. Factor analyses were then performed on the intercorrelation matrices. The general results of these analyses were the identification of 14 dimensions of culture each of which was reasonably stable over culture regions and interpretable in terms of functional relationships. Hierarchical cluster analyses were also performed on the intercorrelation matrices for the dual purposes of sorting out spurious results attributed only to a particular method of analysis and also of developing an empirical model of the dimensional structure of culture. The theoretical implications, the utilizations, and the extensions of the results in future research were considered. [Ethnographic Atlas, cultural dimensions, culture trait associations, multivariate structural analyses]
Spontaneous mode locking in mixed-broadened laser oscillators

A theoretical model is reported for spontaneous mode locking in mixed-broadened laser oscillators. Experimental observations of this effect have been available for many years, but no rigorous interpretation has been given. Numerical calculations emphasize the case of a high-gain xenon laser, for which extensive experimental data have been published. Complex pulsation characteristics are observed as the cavity length and pumping rate are varied, and the theoretical results are in good agreement with the experimental data.
Improved Outcomes with Computer-Assisted Instruction in Mathematics and English Language Skills for Hispanic Students in Need of Remedial Education at Miami Dade College, Florida

In this study, 180 first-time-in-college (FTIC) students at Miami Dade College, Florida in need of remedial instruction in basic mathematics, reading, and sentence skills utilized the A + dvancer® College Readiness Online software. Significant results were found with increased ACCUPLACER® scores; number of students who avoided at least one remedial course; number of students who avoided remediation; number of students who advanced a level within the remedial coursework sequence, enrolled in the next level coursework, and also passed the next course. These results suggest that institutions can use computer-assisted instruction to efficiently allocate resources while addressing the need to provide remedial education in efficient and effective ways. Partial data from this study and results were used to successfully apply for a $1.4 million dollar Federal grant from the U.S. Department of Education to assist with student success, retention, and degree completion.
Umsetzung zwischen festen Stoffen und Lösungen. I. Calciumphosphat und Natriumcarbonat

1. Die gunstigsten Bedingungen fur die Reaktion zwischen Natriumcarbonatlosung und einem gefallten kauflichen Tricalciumphosphat wurden bestimmt und mit denen fur Knochenasche verglichen.
Localization of vimentin, the nonspecific intermediate filament protein, in embryonal glia and in early differentiating neurons. In vivo and in vitro immunofluorescence study of the rat embryo with vimentin and neurofilament antisera.

Abstract Antisera raised against vimentin, the protein subunit of nonspecific intermediate-sized filaments (IFs), were used in conjunction with neurofilament (NF) antisera to study the early development of neurons and glia in the rat embryo. Vimentin-positive fibers spanning the entire thickness of the neural tube including the cerebral vesicles were first observed on Day 12, concomitant with the appearance of NF protein in more confined areas (anterolateral regions of spinal cord and brain stem; motor roots emerging from the NF-positive areas). From Day 15 onwards vimentin and NF antisera selectively decorated glia and neurons, respectively, both in vivo and in vitro . Before Day 15 it appeared that NF-positive structures also stained with antivimentin in cryostat sections. In vitro experiments confirmed the presence of vimentin in early differentiating neurons. NF-positive cells were observed which also reacted with antivimentin in cultures obtained from 13- and 14-day embryos, but not later in development. Most neurons in these cultures became vimentin negative after 2–3 days in vitro .
Reconsideration of Paleomagnetic Data in Terms of Wandering Continents and a Stable Magnetic Pole

Paleomagnetic data, normally presented in terms of paleopole positions, can be represented as paleolatitude and paleo-orientation calculated at an arbitrary reference site. In this form, the data can be used to derive the equation of motion of the region sampled, in terms of a particular model of the motion. For the plate tectonics model, the motion of the plates is sufficiently constrained that the position of the pole of opening can be derived directly from the paleomagnetic data. A mean North Atlantic pole of opening has been calculated from 38 paleomagnetic observations, ranging in age from 1.5 to 225 m.y., from the United States and southern Canada. The calculated pole of opening is near the Arctic coast of Siberia, in disagreement with a mean pole of opening near Iceland, inferred from sea-floor-spreading data. Sea-floor and paleomagnetic data considered together indicate that the North Atlantic system has moved northward relative to a fixed frame of reference aligned with the geomagnetic field. A westward component of movement may be present also but cannot be resolved.
Comparison of surface emissions and subsurface distribution of cis- and trans-1,3-dichloropropene and chloropicrin in sandy field beds covered with four different plastic films.

The purpose of this study was to conduct a field study at a Florida field site on surface emissions and subsurface distribution of cis-and trans-1,3-dichloropropene (1,3-D) and chloropicrin (CP) in raised beds injected with Telone C35 with four replications. A total of 16 beds were applied with Telone C35 by chisel injection and covered with four different plastic films, 4 beds for each film. Each bed was installed with five 20-cm long soil pore air probes and a surface air collection pan at arbitrarily locations along the length of each bed for sampling soil pore air and surface air, respectively, for analysis of the three biologically active compounds, cis- and trans-1,3-D and CP. We found that average concentrations of the three compounds at 20-cm depth among the beds covered with four different plastic films generally were not statistically different. Among the four beds covered with the same plastic film, average concentrations of the three compounds were statistically different only in the four meta...
Mycobacterial and Other Serious Infections in Patients Receiving Anti-Tumor Necrosis Factor and Other Newly Approved Biologic Therapies: Case Finding through the Emerging Infections Network

We present the results of a nationwide survey of infectious disease consultants to identify mycobacterial and other serious infections in patients receiving anti-tumor necrosis factor compounds and other novel targeted therapies. Nontuberculous mycobacterial infections, histoplasmosis, and invasive Staphylococcus aureus infection were all reported more frequently than was tuberculosis disease in this context.
Expert Design Advisor

The authors present a methodology for the development of large, complex systems involving next-generation mission-critical combat computing resources and an automation toolset using an artificial intelligence expert system shell. The methodology optimizes the design structure including the generating of near-optimal allocations of logical design objects to physical implementations based on heuristic classes of rules, classes of algorithms, sets of analytical equations, and sets of probabilistic reasoning. >
Large magnetoresistance at room temperature in semiconducting polymer sandwich devices

A thin-film-sandwich device is fabricated consisting of poly(9,9-dioctylfluorenyl-2,7-diyl) sandwiched between two electrodes to study magnetoresistance (MR) effect in semiconducting polymer OLEDs. MR measurements at room temperature for different voltages show that MR traces are independent of the temperature and the angle between film plane and applied magnetic field. However a dependence on the film thickness is observed for an increase in turn-on voltage with increasing film thickness. Hence, MR effect is a bulk rather than an (electrode) interface effect.
Simulating L3 caches in real time using hardware accelerated cache simulation (HACS): a case study with SPECint 2000

Trace-driven simulation is a commonly used tool to evaluate memory-hierarchy designs. Unfortunately, trace collection is very expensive, and storage requirements for traces are very large. In this paper, we introduce HACS (Hardware Accelerated Cache Simulator), and describe the validation methods we used to demonstrate functionality. We also present some initial cache simulation results from SPECint 2000. We then propose future directions for research with HACS.
Do Firms Have Short Memories? Evidence From Major League Baseball

>> When deciding what salary to offer an employee, a firm needs to predict that employee’s future productivity. One piece of information that a firm can use to predict productivity is the employee’s past performance record. Classical theory predicts that firms will effectively use the available information to choose an appropriate salary offer. Evidence from baseball contracts indicates, however, that memory-based biases influence salary offers. Consistent with insights from psychology and behavioral economics, salaries are affected too much by recent performance compared with past performance. All organizations do not suffer equally from short memories. The teams that achieve the most with the money that they spend also use past performance data most effectively.
Nanoscale internally referenced oxygen sensors produced from self-assembled nanofilms on fluorescent nanoparticles.

A novel sensor fabrication concept using indicators trapped in nanoengineered ultrathin films deposited on fluorescent nanoparticles is demonstrated for oxygen sensing. The nanoscale systems are based on the quenching of tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II) immobilized within polyelectrolyte multilayers deposited on the surface of nanoparticle templates. The ionically bound nanofilms create a porous scaffold into which controlled precipitation of the chromophore is achieved using a combination of electrostatic attraction and dye insolubility in water. The fluorescent nanoparticles act as physical scaffolds and also provide a complementary spectral signature for use as an internal intensity reference. Oxygen sensors created on 100-nm yellow-green fluorescent particles exhibit a linear Stern-Volmer behavior with a quenching constant of 1.06/mM and sensitivity of 60%, which demonstrates that the dye is still partially accessible to oxygen following immobilization. To demonstrate the feasibility of intracellular metabolic monitoring with such nanoprobes, the oxygen sensors were chemically delivered into human dermal fibroblasts with no apparent loss in cell viability. The results prove that the approach to sensor production is facile and leads to sensitive systems that can be further optimized for improved response, and these findings support the further development of similar self-referenced probes toward quantitative intracellular analysis.
Don't forget the laptop: using native input capabilities for expressive musical control

We draw on our experiences with the Princeton Laptop Orchestra to discuss novel uses of the laptop's native physical inputs for flexible and expressive control. We argue that instruments designed using these built-in inputs offer benefits over custom standalone controllers, particularly in certain group performance settings; creatively thinking about native capabilities can lead to interesting and unique new interfaces. We discuss a variety of example instruments that use the laptop's native capabilities and suggest avenues for future work. We also describe a new toolkit for rapidly experimenting with these capabilities.
Utilization of fuel oils by fungi isolated from oceanic tar balls

Filamentous fungi were isolated from approximately half of 300 tar balls collected from the north Atlantic and the north Pacific Oceans. Forty-two isolates were tested for their ability to utilize no. 2 and no. 4 fuel oils as the sole carbon source at 2 different concentrations. Isolates of Aspergillus, Graphium, Humicola, Lophotrichus, Penicillium, and Tetracoccosporium were found that produced extensive growth.
A 3.6GB/s 1.3mW 400mV 0.051mm 2 near-threshold voltage resilient router in 22nm tri-gate CMOS

A 6-port, 2-lane packet-switched input-buffered wormhole router forms the key building block of a 2×2 2D mesh network-on-chip (NoC). The router operates across a wide frequency (voltage) range of 1GHz (0.85V) to 67MHz (340mV), dissipating 28.5mW to 675μW and achieves 3.3X improvement in energy-efficiency at an optimum supply voltage (VOPT) of 400mV. The resilient router incorporates an end-to-end forward error correction code (ECC) and within-router recovery from transient timing failures using error-detection sequentials and a FLIT replay scheme, to achieve 28% (at 0.7V) to 63% (at VOPT) higher bandwidths.
Displaced Intra-Articular Fractures Involving the Volar Rim of the Distal Radius

Purpose To describe the features of displaced intra-articular fractures confined to the volar rim of the distal radius and compare outcomes after their operative fixation to complete intra-articular and extra-articular fractures treated with operative fixation. Methods A total of 627 distal radius fractures were treated over a 6-year period. Twenty-eight patients had volar rim fractures (type 23-B3, as classified by the Orthopaedic Trauma Association [OTA]), all treated with operative reduction and fixation using a volar buttress plate. Clinical outcome information including radiographs, Short Form–36 health survey, and Disabilities of the Arm, Shoulder, and Hand questionnaire were collected at regular postoperative intervals. Patients with volar rim fractures were compared with patients who sustained other types of operatively managed distal radius fractures (OTA types 23-A, 23-B1/B2, and 23-C). Results The most common type of volar rim fracture consisted of a single large fragment (OTA 23-B3.2; 46%), followed by comminuted fractures (OTA 23-B3.3; 36%). Restoration of radiographic parameters was similar between groups except for an increased volar tilt in volar rim fractures compared with group 23-B1/B2. Active wrist and finger motion improved in all groups except for wrist extension, which was less in the 23-B1/B2 groups. The 23-B1/B2 group had the greatest pain and worst Short Form–36 scores. Disabilities of the Arm, Shoulder, and Hand questionnaire scores were similar and without differences between groups. Conclusions Our data suggest that patients with volar rim distal radius fractures can expect a rapid return to function with minimal risk for complications and have outcomes similar to other types of operatively treated distal radius fractures. Further investigation of type 23-B fractures (23-B1/B2) is warranted owing to evidence of diminished outcomes. Type of study/level of evidence Therapeutic III.
Grass-Roots Perspectives on Global Policies for Development

Global policy for development emerges out of a process that reaches from the grass roots to global organizations. From a Third World perspective, several typologies of local, national, and international development organizations are presented, along with case studies examining problems encountered in their relationships. From a First World perspective, local development education and advocacy organizations are examined, along with links between these organizations and national organizations, international organizations, and grass-roots organizations in the Third World. Given the strong participatory assertions from the grass roots, is it possible that development (i.e. full development of human potential) can only be achieved by a highly decentralized global policy process? What kinds of state and global institutions, if any, would this imply?
Pregnancy and Thromboembolic Disease

Women with a previous history of thrombosis are at increased risk for having a clot when pregnant. The risk of VTE recurrence without anticoagulation is up to 12% in some studies, but falls to a very low level with prophylaxis. Prophylactic anticoagulation for at risk patients during pregnancy is an effective and relatively safe measure. Recent large epidemiologic studies have confirmed the significant risk of VTE during and after pregnancy. A review of pregnancy related VTE using the Nationwide Inpatient Sample (NIS), from the Healthcare Cost and Utilization Project (HCUP) of the Agency for Healthcare Research and Quality (AHRQ) examined the period from 2000 to 2001[1]. The database contained 9,058,162 pregnancy admissions and 73,834 postpartum admissions. There were 3375 arterial thromboembolic events (2850 strokes and 525 myocardial infarctions) in addition to 14,335 venous thromboembolic events