cssi/SciSciGPT-SciSciNet huggingface dataset:
Securing Routing in Low Power and Lossy Networks

The Internet Engineering Task Force (IETF) introduced the RPL routing protocol to meet the routing requirements of the lossy networks. The inbuilt security features in the RPL design prevent external attacks but fail to mitigate internal attackers’ threats. The absence of robust security mechanisms in the RPL design has made it vulnerable to different categories of routing attacks. A comprehensive literature review is carried out in this study, which compares the mitigation approaches suggested by different authors in their research work. This paper aims to compare and evaluate different mitigation techniques in order to identify research trends, gaps, and opportunities. The existing research work is compared with one another in terms of the experimental setup, attack focus, proposed methodology, and performance metrics to determine the best approach for tackling the RPL routing attacks.
Feeding People's Curiosity: Leveraging the Cloud for Automatic Dissemination of Mars Images

Smartphones and tablets have made wireless computing ubiquitous, and users expect instant, on-demand access to information. The Mars Science Laboratory (MSL) operations software suite, MSL InterfaCE (MSLICE), employs a different back-end image processing architecture compared to that of the Mars Exploration Rovers (MER) in order to better satisfy modern consumer-driven usage patterns and to offer greater server-side flexibility. Cloud services are a centerpiece of the server-side architecture that allows new image data to be delivered automatically to both scientists using MSLICE and the general public through the MSL website (http://mars.jpl.nasa.gov/msl/).
PHYSIOLOGY OF NITROGEN FIXATION BY BACILLUS POLYMYXA

Grau, F. H. (University of Wisconsin, Madison) and P. W. Wilson. Physiology of nitrogen fixation by Bacillus polymyxa. J. Bacteriol. 83:490-496. 1962.-Of 17 strains of Bacillus polymyxa tested for fixation of molecular nitrogen, 15 fixed considerable quantities (30 to 150 mug N/ml). Two strains of the closely related B. macerans did not use N(2), but possibly other members of this species may do so. Confirmation of fixation was obtained by showing incorporation of N(15) into cell material. Both iron and molybdenum are specifically required for fixation; without the addition of these metals to the nitrogen-free medium, the growth rate and the total nitrogen fixed were reduced about 30 to 50%. No requirement for added molybdenum could be shown when ammonia was the nitrogen source, and the absence of iron caused only a slight decrease in growth. Washed-cell suspensions of B. polymyxa containing an active hydrogenase readily incorporated N(15) into cell materials when provided with mannitol, glucose, or pyruvate but not when formate was the substrate. Hydrogen is a specific inhibitor of fixation, reducing both the rate and final amount of nitrogen fixed; it did not reduce growth on ammonia. Fixation was strictly anaerobic, 1% oxygen in the gas phase being sufficient to stop fixation. Arsenate is a powerful inhibitor of fixation of N(2) by washed-cell suspensions of B. polymyxa, indicating that high-energy phosphate may be significant for this process.
ICE CORE METHODS | Stable isotopes

Measurements of stable isotope ratios of water in ice cores (18O/16O and D/H) provide fundamental data for ice-core paleothermometry and stratigraphy. Although commonly interpreted as surface temperature indicators at polar ice-core sites, the isotope ratios are influenced by a number of other factors including moisture source temperature, seasonality, other aspects of the hydrologic cycle, and vapor diffusion in the firn. Nonetheless, isotope ratios do respond strongly to temperature change, as indicated by several independent paleothermometry techniques, and can provide quantitative estimates of past temperatures.
Equine Motor Neuron Disease

This article reviews the subject of equine motor neuron disease, a neurodegenerative disease of horses. The authors discuss various topics, including epidemiology, pathophysiology, clinical signs, laboratory findings, diagnosis, and treatment.
Generalized Predictive Control Algorithms with Guaranteed Frozen-Time Stability and Bounded Tracking Error

In its present form, for a fixed plant model GPC (generalized predictive control) guarantees stability only for two specific choices of horizons in the cost function. In one instance, GPC has been shown to result in a deadbeat control law while in the other, the control law has been shown to converge to that given by the solution of the corresponding algebraic Riccati equation. However a lower bound on the costing horizon that results in a stabilizing controller is not known a priori. This paper presents sufficient conditions for stability of closed loop systems that result from implementing solutions of the finite horizon LQ problem for arbitrary fixed costing horizons. On this basis, a class of predictive control laws that ensures frozen-time stability of the closed loop system is proposed. When the plant is required to track a known reference signal that is bounded, the sufficient conditions for frozen-time stability of the closed loop are used to derive a controller structure that guarantees the tracking error to be bounded.
Simulating power semiconductor devices using variable model levels

Model levels for power semiconductor devices are described. For the case of an IGBT and p-i-n diode models, various model levels are presented. First-of-all, an averaged model that captures switching and conduction losses is developed. Then two different behavioral models are developed, which give different levels of accuracy in reproducing switching waveforms. A previously developed physics-based IGBT and diode model is used as a reference for these less accurate, but more computationally efficient models. These models are compared in terms of switching waveform accuracy, switching and conduction loss predictions, model complexity and simulation time.
Comparison of subjective and objective ratings of intelligibility of speech recordings

Some results regarding the evaluation of the intelligibility of speech recordings made under controlled conditions with a variety of microphone systems are presented. The intelligibility of speech recordings made in rooms and other spaces can be affected by a range of factors, including reverberation, noise, distance from talker to microphone, and properties of the microphone system itself. Test speech sentences were recorded, and the intelligibility of those recordings was determined by a subjective listening test. Recordings of test speech sentences were made under controlled conditions in 4 test spaces having widely varying acoustical properties. The intelligibility results for recordings made with four of the microphone systems at one location within each test space showed that the scores for the 2-channel recordings were always higher than the corresponding 1-channel recordings.
Art et archives : le cas Robert Rauschenberg

La maniere dont les artistes s’interessent aux archives peut nous permettre de decouvrir de nouveaux aspects a propos de ces dernieres. C’est sous cet angle que cet article aborde le cas de l’artiste americain Robert Rauschenberg, par le biais de la dimension archivistique de son oeuvre. Dans un premier temps, nous presentons un apercu du mouvement americain des archives dans l’art au cours des annees 1960, au sein duquel s’inscrit Rauschenberg. Nous effectuons ensuite une breve revue de la litterature portant sur les liens qui unissent cet artiste et les archives, pour ensuite aborder sa demarche artistique et son interet pour l’inventaire, l’archivage et la cueillette de documentation. Cet interet pour les archives est notamment perceptible a meme sa collection d’art privee, rendue publique a l’automne 2012. Finalement, une lecture archivistique d’un corpus de trois oeuvres de l’artiste fournit une illustration des particularites de l’utilisation des archives chez Rauschenberg.
Principal bundles over a projective scheme

We prove the existence of a quasi-projective moduli scheme for principal bundles over an arbitrary projective scheme.
THE PREVALENCE AND CORRELATES OF ROSE QUESTIONNAIRE ANGINA AMONG WOMEN AND MEN IN THE LIPID RESEARCH CLINICS PROGRAM PREVALENCE STUDY POPULATION

The prevalence and correlates of Rose Questionnaire angina were investigated in a sample of 4,661 white woman and men aged 30 years and above who participated in the Lipid Research Clinics Program Prevalence Study 1972-1976. Among men, the prevalence of Rose angina increased with age from about 1% to 12%, while the prevalence among women ranged from about 3% to 6%. Young women compared with men also had a relatively high prevalence of dyspnea, which was strongly correlated with Rose angina in both sexes. For women and men younger than 50 years, the dyspnea-Rose angina odds ratio was about 6 (p less than 0.001), while older women and men had somewhat lower sand higher odds ratios, respectively. Major and minor resting electrocardiographic abnormalities and self-reported history of a heart attack were not significantly associated with Rose angina among young participants of either sex, but they did show positive associations among older participants with the exception of minor electrocardiographic abnormalities in men. A logistic regression analysis revealed a strong inverse association between high density lipoprotein cholesterol and Rose angina in both sexes. Because mortality studies consistently show an excess of coronary heart disease death among young men compared with women, the female excess of Rose angina at young ages suggests that the grouping of angina and myocardial infarction into a single endpoint in cardiovascular disease studies may be more appropriate for young men than for young women.
Amplified 2- $\mu{\rm m}$ Thulium-Doped All-Fiber Mode-Locked Figure-Eight Laser

We report the first mode-locked, thulium-doped fiber figure-eight laser. The mode-locked oscillator produces 1.5-ps pulses with 63 pJ of pulse energy at a 10.4-MHz repetition rate with a 3-nm bandwidth at a center wavelength of 2034 nm. After amplification, the pulses are compressed to 370 fs with $\sim$ 50 nJ of pulse energy. The oscillator can also operate in a square pulse regime, yielding stable pulses from $\sim$ 100 ps to 20 ns long with $\sim$ 100 nJ per pulse after amplification.
Assessing Learning, Critical Reflection, and Quality Educational Outcomes: The Critical Incident Questionnaire

This research study incorporates Brookfield’s Critical Incident Questionnaire (CIQ) as a qualitative instrument to assess the ACRL Information Literacy Competency Standards for Higher Education in one library’s instructional curriculum. A sample (n=348) of English Composition II students was studied over the course of two semesters during a four-session instructional program. A methodological framework of critical reflection, incidents, and events was incorporated, as well as reflection on practice. Results of the study showed the CIQ was effective in supporting qualitative methods for assessment of critical reflection in general and the ACRL Standards specifically during the research and learning process.
Synthesis in vitro of a seven amino acid peptide encoded in the leader RNA of Rous sarcoma virus

Abstract Sequences of avian retroviral RNAs suggest that short open reading frames in the putatively untranslated leader sequences might direct the synthesis of small peptides. Previous analyses indicate that translation of Rous sarcoma virus (RSV) RNA in vitro faithfully reflects translation of the viral RNA in the chick cell. Accordingly, we sought to determine if the heptapeptide LP1, encoded in the open reading frame closest to the 5′ end of RSV RNA, could be synthesized in vitro since this would strongly suggest that it might also be synthesized in vivo. Here we confirm that RSV RNA directs the synthesis of LP1 in rabbit reticulocyte lysates. LP1 is rapidly degraded in the lysate by an aminopeptidase activity. On the basis of the following observations, we propose that the open reading frame encoding LP1 plays a role in the life cycle of avian retroviruses. (1) The LP1 open reading frame is ubiquitious with respect to position and length in 12 strains of avian retrovirus. (2) In the amino acid sequences of the 12 strains, only three of the seven residues are invariant. (3) On the basis of the conservation of the −3 and +4 nucleotides flanking the AUG codon, the strengths of initiation for translation of LP1 are approximately the same in the different viruses. (4) The LP1 open reading frame is positioned in front of sites on retrovirus RNA that are required for initiation of cDNA synthesis and for packaging of the RNA into mature virus.
Grip Span and Aging: Does the Grip Strength-Span Relationship Change with Age?

Grip strength has been well studied in conjunction with product and individual characteristics including age. Design characteristics for products targeted to older adults frequently include larger or chunkier handles or grips. To understand motivation for these design choices, this investigation assessed grip strength at 5 grip spans of 31 participants in two age groups. The downward shift in the grip strength/span curve can be attributed to the decrease in strength with age associated with loss of type II muscle fibers in all muscles (which was more pronounced for male participants). However, there was no shift in the grip strength/span curve peak to a wider grip. Thus the affinity for chunkier handles (increased volume, contact surface area, and grip span) and grip designs for older adults is not motivated by a shift in peak grip strength over the tested grip span.
Low temperature mullite crystallization in Al- and Si-alkoxide derived homogeneous gels

Abstract A homogeneous mullite gel (3:2 Al2O3:SiO2 molar ratio) was made from tetraethoxysilane (TEOS) and aluminum isopropoxide (Al(OCH(CH3)2)3) at room temperature within a relatively quick three days. Mullite was the only crystalline phase to form during calcination; metastable phases like aluminosilicate spinel did not appear. When heated at 20 °C/min, crystalline mullite (65 mol% Al2O3) started forming at 575 °C and reached 27 wt.% by 900 °C. Major crystallization occurred at ~ 1000 °C with a concurrent increase of Al2O3 concentration (68–69 mol%) in the mullite phase. The alumina content decreased towards stoichiometric (3Al2O3·2SiO2) mullite at even higher temperatures. When the gel remained in the amorphous state, low temperature preheating significantly improved crystallization at higher temperatures. After preheating at 425 °C for 24 h, 78 wt.% of the final product was crystallized when it was subsequently annealed at 750 °C for 5 min. Only 20 wt.% crystallized without preheating.
Disaggregating human population for improved land use management in Kenya

Understanding the spatial distribution of population across a landscape is important in land use planning. In developing nations, where resources are limited, such information can facilitate more efficient decision-making for resource allocations. This article examines three methods for characterizing the distribution of human population within a natural boundary that overlaps but is substantially different from the geography of the corresponding census data. Using land cover information in conjunction with available census data, simple areal weighting, binary dasymetric mapping, and global regression methods are tested. Strengths and weaknesses of each technique are discussed. Our findings offer a new population estimate for the River Njoro watershed in Kenya and suggest that census data alone are inadequate for many resource management decisions. At the same time, however, care must be taken to account for the spatial characteristics of the environment when developing a model for improved estimates of p...
Unequal cell division, growth regulation and colony size of mammalian cells: a mathematical model and analysis of experimental data.

This work describes mathematically the dynamics of expansion of cell populations from the initial division of single cells to colonies of several hundred cells. This stage of population growth is strongly influenced by stochastic (random) elements including, among others, cell death and quiescence. This results in a wide distribution of colony sizes. Experimental observations of the NIH3T3 cell line as well as for the NIH3T3 cell line transformed with the ras oncogene were obtained for this study. They include the number of cells in 4-day-old colonies initiated from single cells and measurements of sizes of sister cells after division, recorded in the 4-day-old colonies. The sister cell sizes were recorded in a way which enabled investigation of their interdependence. We developed a mathematical model which includes cell growth and unequal cell division, with three possible outcomes of each cell division: continued cell growth and division, quiescence, and cell death. The model is successful in reproducing experimental observations. It provides good fits to colony size distributions for both NIH3T3 mouse fibroblast cells and the same cells transformed with the rasEJ human cancer gene. The difference in colony size distributions could be fitted by assuming similar cell lifetimes (12–13 hr) and similar probabilities of cell death (q = 0·15), but using different probabilities of quiescence, r = 0 for the ras oncogene transformed cells and r = 0·1 for the non-transformed cells. The model also reproduces the evolution of distributions of sizes of cells in colonies, from a single founder cell of any specified size to the stable limit distribution after eight to ten cell divisions. Application of the model explains in what way both random events and deterministic control mechanisms strongly influence cell proliferation at early stages in the expansion of colonies.
Providing care for the changing face of the U.S.

Editor's Note: Because of the dramatic shifts in demographics predicted for the U.S. population in the next 25 years, AWHONN Lifelines is launching a series of articles and departments to discuss the critical issues surrounding providing culturally competent care. This article, the first in a series of three by Susan Mattson, will focus on striving for culturally competent practice, particularly by those who provide perinatal care. Watch for additional topics regarding ng “Cultural Competence” as we increase coverage of this important social change within upcoming issues.
The vanadium(V)-catalyzed oxidation of (1-hydroxyethylidene)bisphosphonic acid, CH3C(OH)(PO3H2)2, by hydrogen peroxide in aqueous solution

Abstract The vanadium(V)-catalyzed oxidation of (1-hydroxyethylidene)bisphosphonic acid, CH 3 C(OH)(PO 3 H 2 ) 2 , by hydrogen peroxide in aqueous solution has been studied at temperatures between 50 and 80°C. In contrast to vanadium(V), six-valent Mo and W are without significant catalytic action, as is SeO 2 , while OsO 4 is only weakly catalytic. With excess substrate a limiting stoichiometry is reached in which ca. 4 mol H 2 O 2 are consumed per mol of substrate oxidized. With excess H 2 O 2 , the reaction competes with catalytic decomposition of the peroxide, and a substantial excess of peroxide is required to consume the substrate completely. The reaction is optimal near pH 1. At higher pH it becomes slower, while at lower pH the catalytic decomposition of H 2 O 2 comes to predominate. The principal reaction products are phosphoric and acetic acids and carbon dioxide, along with lesser quantities of CO and formic acid. The consumption of substrate in the presence of a large excess of H 2 O 2 follows first-order kinetics, but the apparent first-order rate constant shows a weak positive dependence on initial substrate concentration, which may be pH-related, and at high substrate concentration it shows a weak negative dependence on initial [H 2 O 2 ]. The principal reactant appears to be the diperoxovanadium(V) anion, OV(O 2 ) − 2 , but the apparent rate shows a greater-than-first-order dependence on catalyst concentration, suggesting a secondary reaction path involving a dimeric peroxovanadium species. A free-radical mechanism has been proposed in which one-electron reduction of the vanadium accompanies oxidation of the substrate to an intermediate alkoxyl radical species that can yield either acetic acid or CO 2 . This mechanism is supported by the observation that vanadium(V) itself oxidizes the substrate at a measurable rate.
Color Image Segmentation Using Watersheds and Joint Homogeneity-Edge Integrity Region Merging Criteria

Watershed algorithms were originally developed as gray-level dedicated transformations. However, well known scalar watershed algorithms can be easily adapted to include multispectral information, producing color segmentations in agreement with the human perception. The multispectral watershed algorithm introduced in this paper includes the use of a vector gradient for calculating the gradient magnitude image (GMI) and the choice of a uniform color space, such as the L*a*6*, for adapting the dissimilarity measures utilized in the merging stage. Experimental results are presented showing the advantages of the proposed adaptation method as well as advantages of combined homogeneity-edge integrity region merging criterion.
Running, Heart Disease, and the Ironic Death of Jim Fixx

Abstract Jim Fixx was one of millions of Americans who started running in the 1960s, 1970s, and 1980s. Unlike other runners, however, Fixx wrote a best-selling book about running and, ironically, died of a heart attack at the age of 52 years while running. Fixx and the authors of other running books believed heart disease resulted from overcivilization and recommended running as a cure. Running was not merely a physical exercise, according to those authors, but also a way of life. Moreover, those running authors, who were often doctors themselves, advised their readers to listen to their bodies, instead of their doctors. Fixx's adherence to that philosophy offers an explanation for his seemingly irrational behavior—running through chest pain and discomfort.
Low urethral pressure and stress urinary incontinence in women: Risk factor for failed retropublic surgical procedure

Nineteen women with stress urinary incontinence (SUI) and low urethral pressure were compared with 106 patients with SUI and normal urethral pressure. All underwent either a revised Pereyra procedure or Burch retropubic urethropexy, and all had detailed clinical and urodynamic evaluations before their operation and one year postoperatively. Surgical procedures effectively stabilized the bladder base and enabled adequate abdominal pressure transmission to the urethra in both groups of women. In spite of these urodynamic findings, the failure rate in women with stress urinary incontinence and low urethral pressure was significantly higher compared with women with good urethral pressure (50% vs 23% for the Pereyra procedure and 33% vs 12% for the Burch procedure [p less than 0.05]), indicating an etiology for their incontinence other than poor support to the urethrovesical junction; therefore, the need for another approach to cure stress incontinence.
997-91 Glycogen Loading In Vivo Reverses Decreased Function After Ischemic Preconditioning In Vitro

We recently observed that glycogen loading of the heart in vivo improves ischemia tolerance to the same extent as ischemic preconditioning (IP). We have now tested the hypothesis that glycogen loading is beneficial in a protocol where IP per se is not effective. We perfused hearts from fed animals with bicarbonate buffer containing glucose (10 mM). Five min IP with 5 min preconditioning-reperfusion (IP5/5) or 10 min normoxic perfusion (Control, C) were preceded by a 15 min stabilization period and followed by 15 min global. no flow ischemia witl 30 min of reperfusion. Glycogen loaded hearts came from fasted animals, were perfused with buffer containing glucose (10 mM). lactate (10 mM) and insulin (10 mU/ml) and were subjected to the same protocol as IP5/5. Cardiac power and heart rate were assessed continuously. Postischemic recovery was assessed by postischemic power as % of preischemic power. Hearts were freeze-clamped for metabolites. Results Glycogen levels in vivo were higher in the glycogen loaded hearts than in C (140 ± 4.5 vs. 70 ± 6.6 μ mol/g dry). IP5/5 did not improve postischemic recovery compared to C (68.5 ± 3.7% vs. 71.4 ± 3.5% of preischemic power, n = 9 each). However, glycogen loading of this group resulted in a full return of cardiac power post ischemia (101 ± 6.1%, n = 8). Levels of glucose6-phosphate (G-6-P), pyruvate, and lactate were not different in IP5/5 and C and returned to preischemic levels with reperfusion. Glycogen loaded hearts maintained elevated G-6-P and lactate levels with reperfusion. Conclusions Glycogen loading improves ischemia tolerance where IP fails to do so. Thus, glycogen or glycogen breakdown may playa crucial role in myocardial protection.
Association of Acute Interstitial Nephritis with Carnivora, a Venus Flytrap Extract, in a 30-Year-Old Man with Hodgkin’s Lymphoma

Acute interstitial nephritis (AIN) is a common cause of acute kidney injury and has been associated with a variety of medications. This is the case of 30-year-old man with Hodgkin's lymphoma who on routine labs before chemotherapy was found to have acute nonoliguric renal failure. A kidney biopsy was performed and confirmed the diagnosis of acute interstitial nephritis. The patient had taken several medications including a higher dose of Carnivora, a Venus flytrap extract, composed of numerous amino acids. The medication was discontinued and kidney function improved towards the patient's baseline indicating that this may be the possible cause of his AIN. Proximal tubular cell uptake of amino acids increasing transcription of nuclear factor-kappaB is a proposed mechanism of AIN from this compound.
Beyond Steps: The Need for Pedagogical Knowledge in Dance

Abstract This essay explores factors influencing high-quality teaching in dance. The author argues that deficiencies in the skills needed to teach the content of dance (i.e., pedagogical knowledge) pose a bigger threat to effective instruction than familiarity with the subject being taught (i.e., content knowledge). The process of learning to teach not only elucidates the basics of sound pedagogy but also reveals key ideas and personal beliefs about dance that engenders better teaching and learning. The author concludes with suggestions for developing pedagogical knowledge in dance.
Sorption and transport of CO2 above and below the glass transition of poly(ethylene terephthalate)

At temperatures at least 30°C above the glass transition (Tg) the sorption and transport of carbon dioxide in poly(ethylene terephthalate) (PET) can be described conveniently using Henry's law and Fick's law with a constant diffusion coefficient. Below Tg Fick's law with a concentration- dependent diffusion coefficient, coupled with a sorption isotherm which is concave toward the pressure axis adequately describes the observed sorption and transport data. Physical interpretations of the quantitative deviations from Henry's law and the form of the concentration dependence of the diffusion coefficient is provided by a model which hypothesizes dual modes of sorption and separate non zero mobilities of two populations of sorbed species in local equilibrium. The implications of the observed temperature variations of the phenomenological model parameters are discussed. Dilatometric parameters for PET, polycarbonate, and poly(acrylonitrile) (PAN) are shown to correlate well with a simple. relationship developed to explain the existence of the “extra” mode of sorption responsible for deviations from Henry's law for CO in glassy polymers. In the temperature range from Tg to + 20°C, deviations from Fickian behavior are also apparent. These effects are consistent with a transition in the nature of the polymer from an elastic solid below Tg to a viscous liquid above Tg In the narrow temperature range slightly above T the time scale for chain rearrangements apparently approaches that for the diffusion process. The polymer's viscoelastic response to the probing molecule, therefore, causes deviations from the classical time lag predictions. These deviations disappear 30°C above Tg.
Identification of two amino acid residues on Ebola virus glycoprotein 1 critical for cell entry

Using site-directed mutagenesis and retroviral vector pseudotyping of the wild type or mutated glycoprotein of Zaire ebolavirus (ZEBOV), we analyzed 15 conserved residues in the N-terminus of the filovirus glycoprotein 1 (GP1) in order to identify residues critical for cell entry. Results from infectivity assays and Western blot analyses identified two phenylalanine residues at positions 88 and 159 that appear to be critical for ZEBOV entry in vitro. We extended this observation by introduction of alanines at either position 88 or 159 of Ivory Coast Ebolavirus (CIEBOV) and observed the same phenotype. Further, we showed that introduction of each of the two mutations in a recombinant full-length clone of ZEBOV (Mayinga strain) that also carried the coding sequence for GFP could not be rescued, suggesting the mutants rendered the virus non-infectious. The two phenylalanines that are critical for both ZEBOV and CIEBOV entry are found in two linear domains of GP1 that are highly conserved among filoviruses, and thus could provide a target for rational development of broadly cross-protective vaccines or antiviral therapies.
Photochemical Chain Reactions in Amorphous Solids

In this article, we review recent work in the authors' laboratory on the subject of free radical chain reactions of chlorine with small hydrocarbons in amorphous solids. The solids are formed as thin films by spray deposition of the gaseous reagents onto a cryogenic window. Reactions are initiated by excimer laser photolysis at 308 nm, which dissociates a small fraction of the chlorine molecules to atoms. Product yields and branching ratios are determined by infrared absorption spectroscopy. Reactions of chlorine with cyclopropane or cyclobutane proceed by true chain reactions, as evidenced by high product quantum yields (number of product molecules formed per laser photon absorbed by the sample). Measurements of the dependence of the product yield on the relative concentrations of chlorine and hydrocarbon provide clues to the reaction mechanism in the solid state. The cyclobutane reaction appears to involve H atom transfer from cyclobutane to cyclobutyl radical as an intermediate step in the overall reaction. Reaction of chlorine with propane, n-butane, or isobutane does not appear to involve chain propagation and is dominated by radical recombination processes which result in low quantum yields. All of these results are discussed in terms of reactions which occur in a solid state environment where molecular motion is severely restricted.
SU-FF-J-66: Deriving Correlation of External Surface and Internal Tumor Motion Using 4D-CT Images

Purpose: To quantify the correlation between patient surface motion and internal tumor motion. Method and Materials: Thoracic 4D‐CT scans are used for the study. The CTimage at the end of inhale is set as the target image. On each CT slice of the target image, 201 points are evenly placed on the skin contour (excluding the patient's back). The other nine CTimages, corresponding to nine different respiratory phases, are set as moving images. An optical flow deformable image registration algorithm is used to map the moving images to the target image. Then the surface points in the target image are transferred to the moving images using the deformation vector field. The motion trajectory of each surface point is quantified for the ten respiratory phases, and the correlation between each surface point motion and internal tumor movement in the superior‐inferior direction is computed. Results: Color maps of the surface point motion amplitude and correlation with internal tumor motion have been derived for each patient. Color maps highlight the high‐correlation and high‐amplitude motion regions on the surface. It has been observed that 88% of body surface has a correlation of 0.9 or higher with internal tumor motion in the SI direction but only 17% of surface points have motion amplitude bigger than 2mm. Conclusion: Color maps of the surface point motion amplitude and correlation with internal tumor motion have been derived for each patient from a 4D‐CT scan. These color maps can be used to identify patient specific surface regions of interest to be used as surrogates for external gating.
Continuous end-tidal carbon dioxide monitoring in pediatric intensive care units.

Abstract Purpose End-tidal carbon dioxide (ETCO 2 ) monitoring has a variety of clinical applications in critically ill pediatric patients. This study was designed to explore the current availability and utilization patterns for continuous ETCO 2 monitoring in pediatric intensive care units. Methods A Web-based survey was distributed to directors of all accredited pediatric critical care fellowship programs in the United States. Results Sixty-six percent of directors completed this survey. One hundred percent of directors had access to ETCO 2 monitoring for intubated patients and 57% for nonintubated patients. Eighty-three percent of respondents used ETCO 2 monitoring "always" or "often" for endotracheal tube confirmation. Fifty percent of respondents used ETCO 2 monitoring "always" or "often" for cardiopulmonary resuscitation, 38% for moderate sedation, and 5% for acid-base disturbances. All respondents who used ETCO 2 monitoring felt that it was easy to use. The most common reason for not using ETCO 2 monitoring was lack of availability (75%). Conclusions End-tidal carbon dioxide monitoring is widely available and used for intubated patients. However, it could be applied more frequently in other clinical situations in pediatric intensive care units.
Onset of superconductivity at 107K in YBa2Cu3O7 - δ at high pressure

Electrical resistivityρ measurements under pressure have been carried out on the high-temperature superconductor YBa2Cu3O7 − δ as a function of temperature T between 1 and 300 K at various pressures between 8 kbar and 149 kbar. The superconducting transition temperature Tc increases almost linearly with pressure at the rate dTc/dP ∼- 0.13 K/kbar. The onset of Tc, defined as the temperature at whichρ(T) drops to 90% of its extrapolated normal state value, increases from ∼95 K at 8 kbar to 107 K at 149 kbar. These results suggest that higher pressures will yield yet higher values of Tc.
Transcriptional regulation of CXC-ELR chemokines KC and MIP-2 in mouse pancreatic acini

Neutrophils and their chemoattractants, the CXC-ELR chemokines keratinocyte cytokine (KC) and macrophage inflammatory protein-2 (MIP-2), play a critical role in pancreatitis. While acute pancreatitis is initiated in acinar cells, it is unclear if these are a source of CXC-ELR chemokines. KC and MIP-2 have NF-κB, activator protein-1 (AP-1) sites in their promoter regions. However, previous studies have shown increased basal and reduced caerulein-induced AP-1 activation in harvested pancreatic tissue in vitro, which limits interpreting the caerulein-induced response. Moreover, recent studies suggest that NF-κB silencing in acinar cells alone may not be sufficient to reduce inflammation in acute pancreatitis. Thus the aim of this study was to determine whether acinar cells are a source of KC and MIP-2 and to understand their transcriptional regulation. Primary overnight-cultured murine pancreatic acini were used after confirming their ability to replicate physiological and pathological acinar cell responses. Upstream signaling resulting in KC, MIP-2 upregulation was studied along with activation of the transcription factors NF-κB and AP-1. Cultured acini replicated critical responses to physiological and pathological caerulein concentrations. KC and MIP-2 mRNA levels increased in response to supramaximal but not to physiological caerulein doses. This upregulation was calcium and protein kinase C (PKC), but not cAMP, dependent. NF-κB inhibition completely prevented upregulation of KC but not MIP-2. Complete suppression of MIP-2 upregulation required dual inhibition of NF-κB and AP-1. Acinar cells are a likely source of KC and MIP-2 upregulation during pancreatitis. This upregulation is dependent on calcium and PKC. MIP-2 upregulation requires both NF-κB and AP-1 in these cells. Thus dual inhibition of NF-κB and AP-1 may be a more successful strategy to reduce inflammation in pancreatitis than targeting NF-κB alone.
Aromatic and other constituents of four Verbesina species: Structure and stereochemistry of verbesindiol

Abstract Chemical examination of Verbesina sublobata, V gigantea , V. myriocephala and V virginica yielded mainly aromatic aldehydes and acids along with 2,6-dimethoxybenzoquinone and euparin as colouring matters. V virginica also gave the p -coumarate ester of a new sesquiterpenediol, verbesindiol, related to the verbesinols whose structure and stereochemistry were elucidated.
Morse and Melnikov functions for NLS Pde's

The theory of the focusing NLS equation under periodic boundary conditions, together with the Floquet spectral theory of its associated Zakharov-Shabat linear operator $$\hat L$$ , is developed in sufficient detail for later use in studies of perturbations of the NLS equation. “Counting lemmas” for the non-selfadjoint operator $$\hat L$$ , are established which control its spectrum and show that all of its eccentricities are finite in number and must reside within a finite discD in the complex eigenvalue plane. The radius of the discD is controlled by theH 1 norm of the potential $$\overrightarrow q $$ . For this integrable NLS Hamiltonian system, unstable tori are identified, and Backlund transformations are then used to construct global representations of their stable and unstable manifolds-“whiskered tori” for the NLS pde. The Floquet discriminant $$\Delta (\lambda ;\overrightarrow q )$$ is used to introduce a natural sequence of NLS constants of motion, [ $$[F_j (\overrightarrow q ) \equiv \Delta (\lambda = \lambda _j^c (\overrightarrow q );\overrightarrow q )$$ , where λ denotes thej th critical point of the Floquet discriminant Δ(λ)]. A Taylor series expansion of the constants $$F_j (\overrightarrow q )$$ , with explicit representations of the first and second variations, is then used to study neighborhoods of the whiskered tori. In particular, critical tori with hyperbolic structure are identified through the first and second variations of $$F_j (\overrightarrow q )$$ , which themselves are expressed in terms of quadratic products of eigenfunctions of $$\hat L$$ . The second variation permits identification, within the disc D, of important bifurcations in the spectral configurations of the operator $$\hat L$$ . The constant $$F_j (\overrightarrow q )$$ , as the height of the Floquet discriminant over the critical point λ , admits a natural interpretation as a Morse function for NLS isospectral level sets. This Morse interpretation is studied in some detail. It is valid globally for the infinite tail, $$\{ F_j (\overrightarrow q )\} _{|j| > N} $$ , which is associated with critical points outside the discD. Within this disc, the interpretation is only valid locally, with the same obstruction to its global validity as to a global ordering of the spectrum. Nevertheless, this local Morse theory, together with the Backlund representations of the whiskered tori, produces extremely clear pictures of the stratification of NLS invariant sets near these whiskered tori-pictures which are useful in the study of perturbations of NLS. Finally, a natural connection is noted between the constants $$F_j (\overrightarrow q )$$ of the integrable theory and Melnikov functions for the theory of perturbations of the NLS equation. This connection generates a simple, but general, representations of the Melnikov functions.
Curcumin and Dimethoxycurcumin Induced Epigenetic Changes in Leukemia Cells

Curcumin is an ideal chemopreventive and antitumor agent characterized by poor bioavailability and low stability. The development of synthetic structural analogues like dimethoxycurcumin (DMC) could overcome these drawbacks. In this study we compared the cytotoxicity, metabolism and the epigenetic changes induced by both drugs in leukemia cells. Apoptosis and cell cycle analysis were analyzed by flow cytometry. Real-time PCR was used for gene expression analysis. DNA methylation was analyzed by DNA pyrosequencing. The metabolic stability was determined using human pooled liver microsomes. Chromatin Immunoprecipitation was used to quantify histone methylation. Clinically relevant concentration of curcumin and DMC were not cytotoxic to leukemia cells and induced G2/M cell cycle arrest. DMC was more metabolically stable than curcumin. Curcumin and DMC were devoid of DNA hypomethylating activity. DMC induced the expression of promoter methylated genes without reversing DNA methylation and increased H3K36me3 mark near the promoter region of hypermethylated genes. DMC is a more stable analogue of curcumin that can induce epigenetic changes not induced by curcumin. DMC induced the expression of promoter methylated genes. The combination of DMC with DNA methyltransferase inhibitors could harness their combined induced epigenetic changes for optimal re-expression of epigenetically silenced genes.
Measuring the Strength of Teachers' Unions: An Empirical Application of the Partial Independence Item Response Approach.

The literature on teachers' unions is relatively silent about the role of union strength in affecting important outcomes, due in large part to the difficulty in measuring union strength. In this article, we illustrate a method for obtaining valid, reliable, and replicable measures of union strength through the use of a Partial Independence Item Response (PIIR) model. This method uses the individual regulations found within collective bargaining agreements (CBAs) and models their existence as a function of a contract-specific latent level of restrictiveness. This allows for the estimation of (a) a measure of the latent level of relative union strength and associated standard errors of measurement; (b) the reliability of the measure; (c) item severities for each item addressed in the contract, allowing for assessment of item restrictiveness; and (d) contract and item information.
Prolactin-induced protein kinase C activity in a mouse mammary cell line (NOG-8).

Abstract The normal mouse mammary epithelial cells, NOG-8, respond to the mitogenic signal of prolactin with a 2.5-fold increase in cell number within 3 days in vitro. When prolactin is added to subconfluent cells for 5–15 min, there is a 5-fold increase in protein kinase C activity. Upon longer exposure (24 h) to the hormone, the enzyme activity returns to that of control. The potent protein kinase C inhibitor, 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride (H7), blocks both the prolactin-induced enzyme activity and subsequent increase in cell number. Prior to prolactin treatment, 90% of the protein kinase C activity resides in the cytosol with only 10% associated with the membranes. After only 5 min of prolactin treatment, 70% of the enzyme activity is now localized to the membranes. These data suggest that prolactin uses the protein kinase C pathway for signal transduction in NOG-8 cells thus leading to enhanced cell growth.
Application of L 1 reconstruction of sparse signals to ambiguity resolution in radar

A novel approach for range-Doppler ambiguity resolution in pulse Doppler radars is presented. The new technique makes use of the sparse measurement structure of the post-detection data in multiple pulse repetition frequency radars and the resulting L0/L1 equivalence. The ambiguity resolution problem is cast as a linear system of equations which is solved for the unique sparse solution. Numerical results show that the ambiguities can be effectively resolved even with the number of measurements much less than the number of unknowns. The proposed technique reduces the number of PRFs required to resolve multiple targets in some cases compared to conventional techniques.
Using collocations for language generation

A large number of wording choices naturally occurring in English sentences cannot be accounted for on semantic or syntactic grounds. They represent arbitrary word usages and are termed collocations. In this paper, we show how collocations can enhance the task of lexical selection in language generation. Previous language generation systems were not able to account for collocations for two reasons: they did not have the lexical information in compiled form and the lexicon formalisms available were not able to handle the variations in collocational knowledge. We describe an implemented generator, Cook, which uses a wide range of collocations to produce sentences in the stock market domain. Cook uses a flexible lexicon containing a range of collocations, from idiomatic phrases to word pairs that were compiled automatically from text corpora using a lexicographic tool, Xtract. We show how Cook is able to merge collocations of various types to produce a wide variety of sentences. Un grand nombre de choix de mots qui s'effectuent naturellement dans la langue anglaise ne peuvent ětre justifyes sur une base syntaxique ou senantique. II s'agit ?usages arbitrages qu'on appelle des collocations. Dans cet article, les auteurs demontrent comment les collocations peuvent facilite'r le choix lexical dans la generation de langage. Les systemes de generation precedents n'etaient pas en mesure de tenir compte des collocations pour deux raisons: ils ne possedaient pas ľinformation Iexicale sous forme de compilation et les formalismes lexicaux disponibles n'etaient pas capables de traiter les variations dans les connaissances reliees aux collocations. Les auteurs decrivent un generateur implemented appele Cook, qui utilise une vaste gamme de collocations afin de produire des phrases dans le domaine de la bourse. Cook a recours a un lexique flexible contenant une variete de collocations allant des expressions idiomatiques aux paires de mots, compilees automatiquement a partir de textes aľaide ?un outil lexicographique appele Xtract. Cet article illustre de quelle facon le generateur Cook fusionne des collocations de divers types afin de produire une grande vartete de phrases.
Uncertainty, attentional capacity and chromatic mechanisms in visual search

Two general questions were investigated using a visual search task. First, we asked whether effects of target uncertainty on reaction time varied with the discriminability of the target and distractors. Second, a higher order chromatic mechanism model was tested against a flexible model in which the signals in cardinal color-opponent mechanisms are combined through an attentional process. The models were tested by measuring the effects of target uncertainty on search time. A regression analysis indicated that the magnitude of the uncertainty effect was approximately constant in logarithmic units as a function of the chromatic difference between the target and distractors. The constant magnitude of the uncertainty effect suggested that an attentional capacity limit was exceeded when observers were required to monitor several chromatic mechanisms at several locations. The results of experiments 3 and 4 suggested that search for chromatic targets among distractors was mediated by diagonally tuned higher order chromatic mechanisms, rather than by signals in cardinal color-opponent mechanisms that were combined through an attentional mechanism.
Remote sensing of vegetation stress using CO2 laser reflectance characteristics

A tunable thermal-infrared carbon-dioxide laser reflectance sensor operating in the 9-11 micrometer region of electromagnetic spectrum is being used to study plant physiological changes due to stresses. The system is capable of gathering information at various wavelengths, incident angles, and linear polarization combinations. Preliminary reflectance measurements of two different plant types demonstrate the possible potential of this system to characterize physiological changes due to induced freezing, chilling, and heat stresses.