cssi/SciSciGPT-SciSciNet huggingface dataset:
Oscar Vladislas de Lubicz Milosz: Sa voix propre

Plus qu'aucune autre langue litteraire, le francais s'entoure de defenses.1 Defenses internes d'abord: celles de son orthographe regie par d'obscurs scrupules etymologiques; celles de sa syntaxe aux regles subtiles, souvent rationnelles, mais criblees d'exceptions encore plus subtiles, reseau d'une veritable casuistique. Defenses exterieures aussi, d'une formidable institution litteraire seculaire dressant autour de ce jardin secret la garde intimidante de ses dictionnaires et de ses grammairesle Larousse, le Littre, le Dictionnaire de l'Academie, le Bescherelle, le Grevisse, pour ne citer que les modernes, aussi conservateurs que leurs aines. On pourrait donc s'etonner que tant d'etrangers, depuis Marco Polo jusqu'a Samuel Beckett, aient ose se faire auteurs dans une langue qui sait si bien pousser au desespoir ses propres enfants. L'entreprise est doublement suicidaire quand il s'agit de poesie. La, le Saint des saints est tout herisse d'Arts poetiques, de Dictionnaires de rimes, de Traites de versification et d'une tradition si longtemps retrograde et puriste que, jusqu'a une epoque relativement recente, on avait encore tendance a ne voir dans le vers librememe le vers relativement libre d'un Laforgue ou d'un Verhaerenqu'une aberration un peu honteuse et tres peu francaise. Et pourtant, cette poesie francaise, et cela de surcroit pendant la periode la plus complexe, la plus hermetique de son histoire, attirait a son dangereux exercice une pleiade d'etrangers dont beaucoup l'ont illustree, a demeure ou en passant: Stuart Merrill, Rilke, d'Annunzio, T. S. Eliot, Marinetti, etc. Parmi ces aventureux, la place de Milosz est celle, generalement reservee aux natifs, des rares grands poetes qui exercent sur les generations suivantes une fascination et une influence durableset de fait, on ne voit guere qu'Apollinaire qui jouisse d'une situation comparable. Cette influence est evidemment celle d'un grand visionnaire, mais je crois que l'on peut avancer, sans pour autant vouloir le diminuer, que Milosz
Novice/expert differences in programming skills

Automation is the ability to perform a very well-practised task rapidly, smoothly and correctly, with little allocation of attention. This paper resports on experiments which sought evidence of automation in two programming subtasks, recognition of syntactic errors and understanding of the structure and function of simple stereotyped code segments. Novice and expert programmers made a series of timed decisions about short, textbook-type program segments. It was found that, in spite of the simplicity of the materials, experts were significantly faster and more accurate than novices. This supports the idea that experts automate some simple subcomponents of the programming task. This automation has potential implications for the teaching of programming, the evaluation of programmers, and programming language design.
Surface antigen(s) of SV40-transformed tumor cells.

Cells transformed by SV40 virus acquire new antigens on the cell surface. One of these antigens, designated as surface, or S, antigen, has been demonstrated with serological tests, such as the mixed hemagglutination (MHA) or indirect immunofluorescence (IF). While confirming our original observations on the specificity of the immunological changes, we found evidence that the serologically detected neoantigen(s) on the SV40-transformed cell surface were not virus-specific products, but rather components of the normal cell surface exposed by a virus-specific “uncovering” mechanism. Cell lines transformed spontaneously or by polyoma virus, as well as nontransformed lines, can be converted from an MHA or IF nonreactive to a reactive state by mild short-term treatments with certain proteolytic enzymes. The antigen(s) thus exposed crossreact with the antigen(s) on the SV40-transformed cell surface, as demonstrated by MHA or IF tests and cross-adsorption studies, regardless of the species of origin of the line. Although it has not been possible to define the nature of the antigen(s) concerned, it is unlikely that the antigenic specificity is determined by hematoside or H-acetylglucosamine or that it crossreacts with Forssman antigen(s).
Estimating forest carbon fluxes in a disturbed southeastern landscape: Integration of remote sensing, forest inventory, and biogeochemical modeling

[1] Quantifying carbon fluxes between the atmosphere and land surface requires detailed knowledge of the disturbance regime as well as the photosynthetic response of vegetation to climate. In this study, we use a combination of satellite remote sensing, forest inventory data, and biogeochemical modeling to assess forest carbon fluxes from central Virginia, a landscape pervasively disturbed by harvest. Using historical Landsat imagery, we have reconstructed the disturbance history and age structure of forest stands at a resolution of 90 m, from 1973–1999. Forest inventory data provide breakdowns of forest type and age structure for older stands. These data, together with climate and vegetation greenness from advanced very high resolution radiometer (AVHRR), are used as inputs to a version of the Carnegie-Stanford-Ames (CASA) biogeochemical model, which simulates the uptake, allocation, and respiration of carbon and associated effects of disturbance. Modeling results indicate that forests in the study region have an average net ecosystem productivity (NEP) of ∼80 gC m−2 yr−1, reflecting the young age structure of rapid-rotation forests. Variability in annual forest carbon fluxes due to variations in clearing rate and climate are also examined. We find that observed variations in clearing rate may account for NEP variability of ∼30 gC m−2 yr−1, while observed variations in climate may account for NEP variability of 80–130 gC m−2 yr−1. Increased temperatures tend to drive both increased photosynthesis and increased heterotrophic respiration, buffering the system from larger swings in NEP. However, this response depends strongly on stand age.
SWNT Enhanced PEM Fuel Cells

Considerable interest exists in the application of single wall carbon nanotubes (SWNTs) to proton exchange membrane fuel cells (PEMFCs). Proposed applications include use as anode materials in both hydrogen and direct methanol fuel cells, solid polymer electrolyte additives, active cathode materials, and bipolar plate interconnects. SWNTs have extremely high electrical conductivity and catalytic surface areas which make them potentially outstanding active materials for PEMFC electrodes. Additionally the enhanced mechanical properties may play a roll in developing new fuel cell designs such as thin-film microelectronic fuel cells. In a previous study SWNTs were combined with commercially obtained E-TEK Vulcan XC-72 and Nafion® to produce composite cathode membranes. The addition of nanotubes resulted in enhanced fuel cell performance over an equivalent weight percent doping of E-TEK alone. This increased performance was achieved with a 50% reduction in the quantity of platinum present in the cathode. In the present study we investigate fuel cell performance when both the anode and cathode membranes contain graphite, platinum and SWNTs. The SWNTs were characterized by use of thermogravimetric analysis, Raman and UV/VIS/NIR spectroscopes as well as high resolution field emission scanning electron microscopy. Fuel cell performance was determined by comparison of the IV characteristics.© 2004 ASME
Epidemiologic Perspective on Causality Assessment for Drug Associated Events

The study of causality of suspected adverse drug reactions (ADRs) forces us to look at our state of knowledge about drugs. Frequently, effects associated with a drug in the product label or literature are variably related to that drug and sometimes are only an expected event for the population exposed to the drug. Frequency and likelihood of causation are seldom known. Examples of this imperfect state of knowledge and the reasons for it are elaborated, citing the standard sources of information: clinical trials, spontaneous reports, and epidemiologic methods — cohort and case control studies. Each method generates data not amenable to standard statistical analysis. It is proposed that these data can be evaluated using Bayesian methods, which in turn would provide guidance for improved study design.
Nuclear Data Sheets for A = 232,236

Abstract Experimental data pertaining to nuclear structure of nuclei with mass numbers A=232, 236 have been compiled and evaluated.
Discovering rhetorical imprints: La Follette, “Iago,” and the melodramatic scenario

Analysis of a speaker's lifework may reveal a rhetorical imprint, a recurring pattern of distinctive features that characterize his or her discourse regardless of subject, occasion, or context. This essay illustrates the rhetorical imprint in selected speeches of Robert M. La Follette, Sr.
Comments on “markovian processes with identifiable states: General considerations and applications to all-or-none learning”

When knowledge of the response sequence permits one to specify the sequence of theoretical states that occurred, we propose to say that the theory has observable states. Our earlier usage of “identifiable” conflicts with established usage in econometrics. We also present a revised definition of implication between theories that avoids a technical flaw in the earlier definition, and we correct a mistake in an example in our earlier paper.
Cancer Stem Cells: Repair Gone Awry?

Because cell turnover occurs in all adult organs, stem/progenitor cells within the stem-cell niche of each tissue must be appropriately mobilized and differentiated to maintain normal organ structure and function. Tissue injury increases the demands on this process, and thus may unmask defective regulation of pathways, such as Hedgehog (Hh), that modulate progenitor cell fate. Hh pathway dysregulation has been demonstrated in many types of cancer, including pancreatic and liver cancers, in which defective Hh signaling has been linked to outgrowth of Hh-responsive cancer stem-initiating cells and stromal elements. Hence, the Hh pathway might be a therapeutic target in such tumors.
Exploiting target amplitude information to improve multi-target tracking

Closely-spaced (but resolved) targets pose a challenge for measurement-to-track data association algorithms. Since the Mahalanobis distances between measurements collected on closely-spaced targets and tracks are similar, several elements of the corresponding kinematic measurement-to-track cost matrix are also similar. Lacking any other information on which to base assignments, it is not surprising that data association algorithms make mistakes. One ad hoc approach for mitigating this problem is to multiply the kinematic measurement-to-track likelihoods by amplitude likelihoods. However, this can actually be detrimental to the measurement-to-track association process. With that in mind, this paper pursues a rigorous treatment of the hypothesis probabilities for kinematic measurements and features. Three simple scenarios are used to demonstrate the impact of basing data association decisions on these hypothesis probabilities for Rayleigh, fixed-amplitude, and Rician targets. The first scenario assumes that the tracker carries two tracks but only one measurement is collected. This provides insight into more complex scenarios in which there are fewer measurements than tracks. The second scenario includes two measurements and one track. This extends naturally to the case with more measurements than tracks. Two measurements and two tracks are present in the third scenario, which provides insight into the performance of this method when the number of measurements equals the number of tracks. In all cases, basing data association decisions on the hypothesis probabilities leads to good results.
History of the bubble chamber and related active- and internal-target nuclear tracking detectors

Abstract Donald Glaser, 1960 Nobel laureate in Physics, recently passed away (2013), as have many of his colleagues who were involved with the early development of bubble chambers at the University of Michigan. In this paper I will review those early years and the subsequent wide-spread application of active-target (AT) bubble chambers that dominated high-energy physics (HEP) research for over thirty years. Some of the related, but more modern nuclear tracking detectors being used in HEP, neutrino astrophysics and dark-matter searches also will be discussed.
A Modified News Micropayment Model for Newspapers on the Social Web

This theoretical article explores the idea of small, per-article payments for the newspaper industry. The article examines existing academic and industry literature on micropayments, as well as explores underlying theories in media management and economics, marketing, behavioral economics, sociology, computer information systems, and mass communication. The authors propose a “Modified News Micropayment Model” that contains 4 primary drivers that make the idea of micropayments a feasible and attractive idea for news industries in the Social Web environment—socialization/sharing, a microearn component, local focus, and a centralized banking system. The model is presented and discussed, and future directions for research are offered. ACCESS TO FULL TEXT
Cloning and Characterization of the Promoter Region of the Rat Taurine Transporter Gene: Transcriptional Regulation by Taurine and Estradiol 1809

Expression of the renal taurine transporter gene is regulated by intracellular taurine content. In certain cell lines, transcription is regulated by taurine availability. We attempted to define the nature of the signal for this adaptive response. A clone containing a segment of the 5′- upstream region of rat taurine transporter genomic DNA was obtained by screening a P1 library using PCR probes derived from rat brain taurine transporter cDNA (rB16a). The DNA (≈1.6 kb pairs) was isolated and characterized. The 5′-flanking region of the gene contains typical eukaryotic promoter elements, including a TATA box, four consensus binding sites for SP1, and two estrogen receptor half-site sequences (AGGTCA). The DNA fragment was also analyzed by transient transfection. When linke to a firefly luciferase reporter gene, it enhanced transcription 100-fold in two renal cell lines, and was influenced by the presence or absence of taurine. Promoter activity was also enhanced by treatment with β-17 estradiol in human breast cancer cells, and in rat cardiomyocytes, but not in renal cells.
Testing Ricardian equivalence under uncertainty

This paper uses experimental methods to analyze Ricardian equivalence when the probability of debt retirement is less than one. The results suggest that the presence of outstanding debt and the probability of debt retirement have a strong influence on savings behavior. When the probability of debt retirement is low, consumption by the current generation increases, as predicted by Keynesian theory. However, as the probability of debt retirement increases, bequests rise to offset the future generation's expected repayment liability, and deficit spending becomes much less expansionary, as predicted by Ricardian theory. In general, the average bequest is significantly larger when an outstanding debt is passed on to the next generation than when no debt exists, regardless of the probability of debt retirement. However, as long as there is some uncertainty about debt repayment, the presence of debt always stimulates some additional consumption, so that strong variants of Ricardian equivalence are not found.
Carbon-14 Time Scale Extended: Comparison of Chronologies

Thermal diffusion isotopic enrichment of carbon-14 has extended the radiocarbon dating range to about 75,000 years ago. Twenty-eight samples obtained up to June 1976, mainly from northwest Europe, were dated. Consideration of the basic assumptions of carbon-14 dating and of the sources of contamination indicates that the ages are generally reliable. Together with the pollen analytic and stratigraphic the dates yield a more detailed radiocarbon time scale for climatic variations in northwest Europe, showing three early glacial interstades. The radiocarbon time scale agrees with the Camp Century chronology and with the thorium-230 ages of corals representing high sea level stands on New Guinea. Ther is a discrepancy between the radiocarbon time scale and the deep-sea chronology, which may be due to correlation errors. With a modified interpretation of the correlation, all four time scales agree within the estimated experimental uncertainties of the dating techniques used.
Phospholipids containing nitrogen- and sulfur-linked chains: kinetics of cholesterol exchange between vesicles

We have examined the kinetics of [14C]cholesterol exchange between unilamellar vesicles formed from the following synthetic glycerophosphatidylcholines: (a) those having acyl (OC(O)R), acylamino (NHC(O)R), carbamoyl (NHC(O)OR), and acylthio (SC(O)R) chains at the sn-2 position, and (b) those having alkyl (OR) and thioalkyl (SR) chains at the sn-1 position. Replacement of the glycerol oxygen atom at the sn-2 position of PC with a NH group did not affect the rate of cholesterol exchange to a significant extent, suggesting that the amide group of sphingomyelin is not primarily responsible for the very slow rate of exchange of cholesterol observed from sphingomyelin vesicles. Replacement of the glycerol oxygen at the sn-2 position of phosphatidylcholine with a sulfur atom caused the rate of spontaneous cholesterol exchange to increase by a factor of 1.6. Substitution of an O-alkyl chain for the acyl chain at the sn-1 position of 2-acylthiophosphatidylcholine or substitution of a thioalkyl chain for the O-alkyl sn-1 chain of 1-alkyl-2-acylaminodeoxyphosphatidylcholine also did not result in a marked difference in cholesterol exchange rate. The data suggest that interactions other than intermolecular hydrogen bonding are involved in determining the rates of intermembrane cholesterol exchange. Significantly, these kinetic studies also lend support to the continued use in model membranes of synthetic sulfur- and nitrogen-substituted phosphatidylcholines, which have been employed to study properties of lipolytic enzymes, since synthetic acylamino- and acylthio-phospholipids form vesicles that give cholesterol exchange rates that closely resemble those found in vesicles prepared with diester-phosphatidylcholines.
Investigating the effectiveness of the surfactant dioctyl sodium sulfosuccinate to disperse oil in a changing marine environment

We investigated the surfactant dioctyl sodium sulfosuccinate (DOSS) and its delivery system Corexit 9500A, used to disperse oil released during the Gulf of Mexico spill during the summer of 2010. DOSS is an organic sulfonic acid salt that acts as a synthetic detergent and disrupts the interfacial tension between the salt water and crude oil phases. The disruption reaches a maximum at or above the critical micelle concentration (CMC). The CMC for the surfactant was determined to be 0.17% solution in deionized water at a pH of 7.2 and a temperature of 21.1 °C (70°F). The CMC is lower in salt water, at 0.125% solution. This has been identified as a “salting out” effect (Somasundaran, 2006). The CMC of DOSS in both saline and deionized water occurred at lower-percent solutions at higher temperatures. The surface tension versus concentration plots can be modeled using a power equation, with correlation coefficients consistently over 0.94. Surface tension versus concentration plots are scalable to fit the desired temperature by the function f(x) = (1/1+Xα), where α =T1/T2. Tests measured the stability of the DOSS micelles when exposed to a continuous UVA radiation. This photodegradation is directly related to the duration of exposure.
Differential alteration of stem and other cell populations in ducts and lobules of TGFα and c-Myc transgenic mouse mammary epithelium

Abstract Genes associated with proliferation are active in stem and progenitor cells, and their over-expression can promote cancer. Two such genes, c-Myc and TGFα, promote morphologically dissimilar mammary tumors in transgenic mice. We investigated whether their over-expression affects population size and cell cycle activity in stem and other cell populations in non-neoplastic mammary epithelia. Results indicated that both cell population and cell cycle regulation are cell type- and microenvironment-specific. To create a tool for identifying and categorizing the five cellular phenotypes by light microscopy, we adapted previously established ultrastructural criteria. Using nulliparous MMTV- c-myc or MT- tgfα mice, we determined and compared the relative sizes the putative stem, progenitor and differentiated cell populations. PCNA staining was used to compare the portion of each cell population in the cell cycle. Cell population sizes were analyzed relative to: (1) their location in ducts versus lobules (microenvironment), (2) genotype, and (3) cell type. Population sizes differed significantly by genotype, depending on microenvironment ( p = 0.0008), by genotype, depending on cell type ( p p = 0.03). The number of cycling cells was also affected by all three factors, confirming that the interplay of cell type, gene expression and three-dimensional organization are very important in tissue morphogenesis and function. We describe a structure in mammary epithelium consistent with that of a stem cell niche, and show that it is altered in MMTV- c-myc and likely altered in MT TGFα transgenic epithelia.
Copper tungstate thin-films for nitric oxide sensing

Abstract CuWO4 thin-films prepared by the pulsed laser deposition technique were studied for monitoring nitric oxide (NO) in the concentration range of 10
Computing van der Waals energies in the context of the rotamer approximation

The rotamer approximation states that protein side-chain conformations can be described well using a finite set of rotational isomers. This approximation is often applied in the context of computational protein design and structure prediction to reduce the complexity of structural sampling. It is an effective way of reducing the structure space to the most relevant conformations. However, the appropriateness of rotamers for sampling structure space does not imply that a rotamer-based energy landscape preserves any of the properties of the true continuous energy landscape. Specifically, because the energy of a van der Waals interaction can be very sensitive to small changes in atomic separation, meaningful van der Waals energies are particularly difficult to calculate from rotamer-based structures. This presents a problem for computational protein design, where the total energy of a given structure is often represented as a sum of precalculated rigid rotamer self and pair contributions. A common way of addressing this issue is to modify the van der Waals function to reduce its sensitivity to atomic position, but excessive modification may result in a strongly nonphysical potential. Although many different van der Waals modifications have been used in protein design, little is known about which performs best, and why. In this paper, we study 10 ways of computing van der Waals energies under the rotamer approximation, representing four general classes, and compare their performance using a variety of metrics relevant to protein design and native-sequence repacking calculations. Scaling van der Waals radii by anywhere from 85 to 95% gives the best performance. Linearizing and capping the repulsive portion of the potential can give additional improvement, which comes primarily from getting rid of unrealistically large clash energies. On the other hand, continuously minimizing individual rotamer pairs prior to evaluating their interaction works acceptably in native-sequence repacking, but fails in protein design. Additionally, we show that the problem of predicting relevant van der Waals energies from rotamer-based structures is strongly nonpairwise decomposable and hence further modifications of the potential are unlikely to give significant improvement.
Demonstration of microtubules in the terminal web of mature absorptive cells from the small intestine of the rat

The terminal web (TW) region of mature absorptive cells in the small intestine of the rat contains an elaborate cytoskeleton which supports the apical microvillus membrane. In studies regarding the structural organization of the cytoskeleton and associated proteins in the small intestine, microtubules have not been mentioned as components of the TW. By transmission electron microscopy of conventional resin-embedded sections of rat small intestine, we observe many microtubule profiles in the TW of mature absorptive cells. These microtubules are found in various orientations, although most course parallel to the long axis of the cell, and many microtubule profiles are seen in close association with smooth-surfaced vesicles.
Near-Wake Measurements of a Delta Wing in a Supersonic Stream

The near-wakeregion of a 75-deg sweptback delta wing wasstudied experimentally in a Mach 2.49 stream. Fivehole conical probe measurements were conducted vertically and horizontally through the primary vortices at the trailing edgeand half-chord downstream oftheplanformfor7-and 12-deg anglesofattack.TheMachnumberand pressure distribution proe les are summarized, and comparisons of e ow properties at different survey stations are presented. A novel calibration approach using a three-dimensional Navier ‐Stokes solver to generate numerically the calibration data for a blunt-nosed e ve-hole conical probe over a range of Mach numbers and pitch angles was employed.Themagnitudeofthepitot,total,andstaticpressuredee citsinthewakeregionincreasedwithincreasing angle of attack for the same measurement plane and decreased with the downstream distance. The swirl proe les have supersonic and high transonic peak magnitudes, and estimated core dimensions suggest vortex stretching in the vertical direction and convection downstream. A decrease in the radial Mach number component cone rms the vortex trajectory changes from a strong downward e ow over the planform to a gradual return toward the freestream in the near wake. Unlike the experimental results from transonic and low-speed leading-edge vortices, the axial and total Mach number distributions in supersonic vortices are found to be wakelike.
Stress measurement in MEMS using Raman spectroscopy

Raman spectroscopy is used as a non-contact method in measuring stresses at the surface of a crystalline structure or the crystalline-coated surface of an amorphous structure. The stress measurement capability is based on the relative frequency shift of Raman spectra when the crystal lattice is strained. The Raman spectroscopy has a resolution on the order of a few micrometer (micrometers ) which may be used to probe the local non-uniform stress distribution and thus address the material nonhomogeneity. This paper presents the Raman secular equation for general and cubic crystal systems and discusses the stress field effects to Raman frequency shifts and polarization. Experimental testing will include the calibration of the Raman signal versus mechanically applied stresses using single crystal strips, poly-silicon coatings deposited on different specimen configurations, and the stress measurements on a frequently used MEMS structure, cantilever beam, subject to electrostatic forces. Correlation of the experimental results with the analytical prediction will be addressed.
Sensitivity of a refractive beam reshaper to figure error

When a pair of aspheric lenses is used to transform the transverse intensity profile of a laser beam, a deviation of the actual lens surfaces from their ideal shape causes the output beam to deviate in intensity and phase from the intended profile. In this paper, geometrical optics and the paraxial approximation are applied to derive simple expressions for the effect of small errors in the slope and curvature of the lens surfaces on the output intensity profile produced by a refractive beam reshaper. The results are applied to a Gaussian-to-flattop reshaper, which has been described in detail in previous publications,and provide insight into the tolerances required of the optics. For example, if the output intensity is required to be within 5% of the design value, then the tolerance on the lens curvature at the optic axis is less than 2%
Random sequential adsorption

Abstract By placing at random disks onto a surface, but adsorbing only those that do not overlap previously adsorbed disks, one will finally reach the jamming limit beyond which no more disks can be adsorbed. We find, using computer simulations, that the coverage at the jamming limit is θ = 0·547 ± 0·002 for disks and θ = 0·562 ± 0·002 for aligned squares. For the jammed state we have evaluated the pair correlation function for the disks and the size distribution for non-overlapping holes. The coverage saturates asymptotically as τ −1 2 , where τ is the number of attempts to place a new disk. From electron microscopic examination of uranyl acetate stained ferritin, we conclude that this iron storage protein adsorbs on carbon in a way consistent with our results for random sequential adsorption.
Clinical Experience and Choice of Drug Therapy for Human Immunodeficiency Virus Disease

To determine if providers experienced in the management of human immunodeficiency virus (HIV) disease preferred different treatment regimens than providers with less experience, we analyzed data from a national survey of primary care providers' preferred regimens for the management of 30 HIV-related medical conditions. We mailed questionnaires to 999 correct addresses of providers in > 20 cities in the United States in May 1996. We received 524 responses (response rate, 52%). We found a statistically significant association between the number of HIV-infected patients cared for by the provider and the likelihood that the provider would report prescribing highly active antiretroviral therapy and multidrug combinations for treatment of opportunistic infections. Providers with few HIV-infected patients were substantially less likely to report using new therapeutic regimens or new diagnostic tools. We concluded that the preferred regimens of experienced providers are more likely to be consistent with the latest information on treatment for HIV disease than are those of less experienced providers.
A Highly Active Anilinotropone-Based Neutral Nickel(II) Catalyst for Ethylene Polymerization

The synthesis of a neutral nickel(II) complex of 2-(2,6-diisopropylanilino)tropone is described. The important attributes of this ligand include a hindered N-aryl ring, a five-membered-ring chelate, and an anionic N-donor. The complex has been characterized in the solid state by X-ray crystallography, and relevant features are discussed. The nickel complex is capable of polymerizing ethylene with a turnover frequency of up to 8.8 × 106 g of PE (mol of catalyst)-1 h-1 and of producing polyethylenes with a wide range of branching numbers by changes in pressure and temperature. The catalyst shows an excellent tolerance for polar additives in ethylene polymerization experiments and is quite insensitive to added PPh3.1
Pomegranate: a fully scalable graphics architecture

Pomegranate is a parallel hardware architecture for polygon rendering that provides scalable input bandwidth, triangle rate, pixel rate, texture memory and display bandwidth while maintaining an immediate-mode interface. The basic unit of scalability is a single graphics pipeline, and up to 64 such units may be combined. Pomegranate's scalability is achieved with a novel “sort-everywhere” architecture that distributes work in a balanced fashion at every stage of the pipeline, keeping the amount of work performed by each pipeline uniform as the system scales. Because of the balanced distribution, a scalable network based on high-speed point-to-point links can be used for communicating between the pipelines.Pomegranate uses the network to load balance triangle and fragment work independently, to provide a shared texture memory and to provide a scalable display system. The architecture provides one interface per pipeline for issuing ordered, immediate-mode rendering commands and supports a parallel API that allows multiprocessor applications to exactly order drawing commands from each interface. A detailed hardware simulation demonstrates performance on next-generation workloads. Pomegranate operates at 87-99% parallel efficiency with 64 pipelines, for a simulated performance of up to 1.10 billion triangles per second and 21.8 billion pixels per second.
Low-level processing of Illumina Infinium DNA Methylation BeadArrays

We propose a novel approach to background correction for Infinium HumanMethylation data to account for technical variation in background fluorescence signal. Our approach capitalizes on a new use for the Infinium I design bead types to measure non-specific fluorescence in the colour channel opposite of their design (Cy3/Cy5). This provides tens of thousands of features for measuring background instead of the much smaller number of negative control probes on the platforms (n = 32 for HumanMethylation27 and n = 614 for HumanMethylation450, respectively). We compare the performance of our methods with existing approaches, using technical replicates of both mixture samples and biological samples, and demonstrate that within- and between-platform artefacts can be substantially reduced, with concomitant improvement in sensitivity, by the proposed methods.
Desktop-VR system for preflight 3D navigation training

Abstract Crews who inhabit spacecraft with complex 3D architecture frequently report inflight disorientation and navigation problems. Preflight virtual reality (VR) training may reduce those risks. Although immersive VR techniques may better support spatial orientation training in a local environment, a non-immersive desktop (DT) system may be more convenient for navigation training in “building scale” spaces, especially if the two methods achieve comparable results. In this study trainees’ orientation and navigation performance during simulated space station emergency egress tasks was compared while using immersive head-mounted display (HMD) and DT-VR systems. Analyses showed no differences in pointing angular-error or egress time among the groups. The HMD group was significantly faster than DT group when pointing from destination to start location and from start toward different destination. However, this may be attributed to differences in the input device used (a head-tracker for HMD group vs. a keyboard touchpad or a gamepad in the DT group). All other 3D navigation performance measures were similar using the immersive and non-immersive VR systems, suggesting that the simpler desktop VR system may be useful for astronaut 3D navigation training.
The role of acyl-CoA:diacylglycerol acyltransferase (DGAT) in energy metabolism

Acyl-CoA:diacylglycerol acyltransferase (DGAT, EC2.3.1.20), a key enzyme in triglyceride (TG) biosynthesis, not only participates in lipid metabolism but also influences metabolic pathways of other fuel molecules. Changes in the expression and/or activity levels of DGAT may lead to changes in systemic insulin sensitivity and energy homeostasis. The synthetic role of DGAT in adipose tissue, the liver, and the intestine, sites where endogenous levels of DGAT activity and TG synthesis are high, is relatively clear. Less clear is whether DGAT plays a mediating or preventive role in the development of ectopic lipotoxicity in tissues such as muscle and the pancreas, when their supply of free fatty acids (FFAs) exceeds their needs. Future studies with tissue-specific overexpression and/or knockout in these animal models would be expected to shed additional light on these issues.
Hydrodynamic Effects of Bilge Keels on the Hull Flow During Steady Turns

The hydrodynamic design of the bilge keels is important for the ship’s resistance and roll performance. It also affects the ship wake field at the propeller plane and can greatly influence the propulsor performances in terms of noise, efficiency and cavitation. The objective of this work is to investigate the effect of bilge keels on the hull flow during steady turns for a displacement ship with a skeg and a bow dome. An Unsteady Reynolds Averaged Navier Stokes Solver (URANS) CFDShip-Iowa, Version 4, developed at the University of Iowa is used to simulate the flow around the Naval Surface Warfare Center-Carderock Division (NSWCCD) ship model# 5617 with bilge keels at different steady turning conditions. The effect of separated flows caused by the bilge keels and the skeg during steady turns on the flow distributions at the propeller plane will greatly influence the flow at the propeller planes. It was observed that during a high speed port turn at full rudder angle, the onset flow to the port side bilge keel was mainly influenced by the flow around the bow dome and the onset flow to the starboard side bilge keel was subject to the free stream hull flow. The drift angle varies along the bilge keel span during steady turning and complex vortical flow structures were developed on the leeward side of the bilge keels due to flow separations caused by the flow over the tip of the bilge keel from the windward side to the leeward side. The vortical flow generated by the starboard bilge keel also merged with the separated flow caused by the skeg and form a streamwise vortical structure that was convected downstream into the propeller plane. The wake field at both port and starboard propeller planes were analyzed from the simulation results. It can be concluded from the analysis that the starboard side propeller plane was subject to a uniform cross flow and the port side propeller plane was subject to a cross flow that consisted of both cross flow component and a mean swirl that was caused by the streamwise vortical flow generated by the flow separation upstream. The cross flow component at the propeller planes can effectively produce side force affecting the lateral motion of the ship. It can be concluded from the simulations that the bilge keels have great influence on the wake distributions at the propeller planes and can affect the propeller performance during maneuvering in terms of hydrodynamic and structural loadings. Great care should be taken to ensure that the bilge keels be designed properly in the future not just for both seakeeping and propulsion, but also for maneuvering.
Investigation of effect of polyurea on response of steel plates to impulsive loads in direct pressure-pulse experiments

Abstract We summarize the results of the response of monolithic steel plates and steel-polyurea bilayer plates to impulsive blast loads produced in direct pressure-pulse experiments, focusing on the deformation and failure modes of the plates. In these experiments, an impulsive pressure pulse is applied to a steel plate through water or soft polyurethane that simulates shock loading with a peak pressure of ∼80 MPa and duration of ∼50 μs, followed by a cavitation period and a post-cavitation peak pressure of ∼40 MPa and ∼400 μs duration. The pressure pulse is produced by a projectile that impacts either a confined water- or soft polyurethane-layer which in turn transmits the pulse and loads the sample supported by a hollow steel cylinder. Using high-speed photography, the deformation and fracturing of some of the plates are also captured. In addition, the total force acting on the steel plate is measured as a function of time in several selected cases. The experimental results suggest that the presence of polyurea on the back face (opposite to the load-receiving side) of the steel plates can enhance the energy absorption of the plates and help to mitigate their failure. On the other hand, when polyurea is placed on the front face (load-receiving side), it will magnify the initial shock effect and promote failure. These experimental results are paralleled by numerical simulations of the entire experiment, employing physics-based models for the DH-36 steel and polyurea ( Amini et al., 2010b .
Embedded definite descriptions: Russellian analysis and semantic puzzles

where "F" and "B" are unary predicate letters corresponding to "... is French" and "... is a beret" and "W2" is a binary predicate letter corresponding to "... is a man who wears ". The common Russellian analysis of such sentences seems to produce questionable readings and miss the most natural one. I suggest an alternative. The project of providing a uniform procedure to eliminate all embedded definite descriptions while preserving logical form, however, faces interesting difficulties. Russell (1918, 1919) does not mention the possibility of embedding descriptions in this way. Whitehead and Russell (1910) "amend" the simple iota notation in order to eliminate ambiguities in the scope of the description operators. For example, "The present king of France is not bald", which is rendered -'BxKx in the original notation, is rendered either as [txKx]-iBtxKx, or as -[txKx]BixKx in the amended. Whitehead and Russell do consider expressions in the amended notation like [txFx][txGx]H2txFxtxGx in which one iota "quantifier" lies within the
On the magnitude of the subgrid scale eddy coefficient

Three-dimensional numerical integrations capable of resolving the energy containing motions at large Reynolds number have tested the nonlinear eddy-viscosity formulation in the two cases when the turbulence is generated by mean shear or by thermal instability. The proportionality constant suggested by Lilly is found to be applicable in the latter case, but a smaller value is found necessary in the presence of mean shear. Spectra of calculated velocity components are shown to deviate from a k5/3 law, as k approaches the grid cutoff wavenumber, in a manner consistent with the application of Reynolds-averaging over grid volumes.
The effect of ingestion of meat on hepatic extraction of insulin and glucagon and hepatic glucose output in conscious dogs

Abstract The effect of ingestion of protein on hepatic extraction of insulin and glucagon and hepatic glucose output were investigated in conscious dogs. The ingestion of meat stimulated both insulin and glucagon secretion but the glucagon response was much more rapid and greater than that of insulin. Secretion of glucagon demonstrated a biphasic pattern while insulin release was monophasic. The fractional hepatic extraction of glucagon increased gradually from the basal value of 15 ± 3% to a peak of 36 ± 5% at 90 min, and that of insulin increased from the basal level of 41 ± 2% to 54 ± 4% at 45 and 60 min. The increased hepatic extraction of glucagon and insulin after meat ingestion may be explained by neural or hormonal signals from the gut. The blood glucose and hepatic glucose output did not increase significantly despite the significant decrease of the portal vein insulin to glucagon molar ratio as well as the significant decrease of the molar ratio of the hepatic uptake of these hormones. The absence of greater hepatic glucose production despite the augmented glucagon secretion and decreased portal vein insulin to glucagon molar ratio could reffect down regulation by glucagon.
Computing a Celis–Dennis–Tapia trust-region step for equality constrained optimization

We study an approach for minimizing a convex quadratic function subject to two quadratic constraints. This problem stems from computing a trust-region step for an SQP algorithm proposed by Celis, Dennis and Tapia (1985) for equality constrained optimization. Our approach is to reformulate the problem into a univariate nonlinear equationφ(μ)=0 where the functionφ(μ) is continuous, at least piecewise differentiable and monotone. Well-established methods then can be readily applied. We also consider an extension of our approach to a class of non-convex quadratic functions and show that our approach is applicable to reduced Hessian SQP algorithms. Numerical results are presented indicating that our algorithm is reliable, robust and has the potential to be used as a building block to construct trust-region algorithms for small-sized problems in constrained optimization.
Dissecting a circuit for olfactory behaviour in Caenorhabditis elegans

Although many properties of the nervous system are shared among animals and systems, it is not known whether different neuronal circuits use common strategies to guide behaviour. Here we characterize information processing by Caenorhabditis elegans olfactory neurons (AWC) and interneurons (AIB and AIY) that control food- and odour-evoked behaviours. Using calcium imaging and mutations that affect specific neuronal connections, we show that AWC neurons are activated by odour removal and activate the AIB interneurons through AMPA-type glutamate receptors. The level of calcium in AIB interneurons is elevated for several minutes after odour removal, a neuronal correlate to the prolonged behavioural response to odour withdrawal. The AWC neuron inhibits AIY interneurons through glutamate-gated chloride channels; odour presentation relieves this inhibition and results in activation of AIY interneurons. The opposite regulation of AIY and AIB interneurons generates a coordinated behavioural response. Information processing by this circuit resembles information flow from vertebrate photoreceptors to 'OFF' bipolar and 'ON' bipolar neurons, indicating a conserved or convergent strategy for sensory information processing.
Residual capacity for avoidance learning in decorticate rats; Enhancement of performance and demonstration of latent learning with d-amphetamine treatments

Unoperated and decorticated rats were trained on a shuttlebox conditioned avoidance response (CAR) according to a sequential schedule of d-amphetamine sulfate (1.0mg/kg) or vehicle injections. Unoperated rats acquired and retained the CAR regardless of drug conditions, with amphetamine tending to increase performance. Amphetamine enhanced locomotor activity in unoperated and operated rats under all conditions. Decorticate rats failed to show evidence of acquisition during initial training whether given amphetamine or vehicle injections. However, amphetamine injections resulted in dramatic increases in CAR performance only in decorticates which had no previous experience with the drug. Return to the vehicle-alone condition was accompanied by returns to low levels of responding. The rapid performance increments and their state-dependent nature suggested not only that rats with neocortical removals could acquire a CAR, but that such animals, trained without drug treatments, can acquire information about the CAR situation which they are unable to employ successfully, and that these “latent” traces can henceforth be expressed under the facilitatory effects of amphetamine.
Differential labeling of depot and active acetylcholine pools in nondepolarized and potassium-depolarized rat brain synaptosomes.

: To test the hypothesis that a pool of newly synthesized acetylcholine (ACh) turns over independently of preformed ACh, compartmentation and K+ -evoked release of ACh were examined in perfused synaptosomal beds intermittently stimulated by 50 mM K+. In resting synaptosomes, endogenous and labeled ACh was distributed between synaptic vesicles and the cytoplasm in a dynamic equilibrium ratio of 4:6. In the absence of new ACh synthesis, five sequential K+ -depolarizations caused a decremental release of preformed labeled ACh totaling 30% of the initial transmitter store. Further depolarization evoked little additional release, despite the fact that 60% of the labeled ACh remained in these preparations. Release of the preformed [14C]ACh was unaltered while new ACh was being synthesized from exogenous [3H]choline. Since the evoked release of [3H]ACh was maintained while that of [14C]ACh was decreasing, the [3H]ACh/[14C]ACh ratio in perfusate increased with each successive depolarization. This ratio was six to ten times higher than the corresponding ratio in vesicles or cytoplasm. These results indicate that the newly synthesized ACh did not equilibrate with either the depot vesicular or cytoplasmic ACh pools prior to release.