cssi/SciSciGPT-SciSciNet huggingface dataset:
Dielectric constant and stability of fluorine doped PECVD silicon oxide thin films

Abstract As device geometry shrinks to 0.35 mm and below, the parasitic capacitance between closely spaced metal lines becomes important in terms of RC time delay in device switching. In this study, we investigated the use of fluorine doped plasma enhanced chemical vapour deposition (PECVD) grown silicon oxide thin film as a low dielectric constant inter-metal dielectric (IMD) material. We evaluated C2F6 and an organometallic liquid source as the F dopant. It was found that the dielectric constant generally decreased as the F concentration increased. However, we also found that above certain F concentration, the F-doped oxide film would become unstable and absorb moisture from ambient. At similar F concentrations, the films deposited with the liquid source are always more stable than those deposited with C2F6. This, in addition to the different stress versus low frequency rf power behaviour between the two types of film, suggests that the already present SiF bond in the liquid precursor results in a denser and more stable film comparing to the C2F6 doped film where interstitial F may be present.
Using 3-dimensional meshes to combine image-based and geometry-based constraints

To recover complicated surfaces, single information sources often prove insufficient. In this paper, we present a unified framework for 3-D shape reconstruction that allows us to combine image-based constraints, such as those deriving from stereo and shape-from-shading, with geometry-based ones, provided here in the form of 3-D points, 3-D features or 2-D silhouettes.
Aeroelastic Tailoring of Composite Wings Exhibiting Nonclassical Effects and Carrying External Stores

Structural and aeroelastic tailoring applied to advanced straight and swept aircraft wings carrying external stores is addressed. The wing structure is modeled as a laminated composite plate exhibiting flexibility in transverse shear and warping restraint effects. The equations of motion and boundary conditions are obtained via Hamilton's variational principle and application of generalized function theory. For a comprehensive representation of the stores, their static weights and inertia terms are considered. Three-dimensional modified strip theory aerodynamics is employed, and the obtained eigenvalue/boundary value problems are solved using the extended Galerkin method. The model is used to investigate the implications of external stores and ply angle orientation on divergence, free vibration, and flutter. Within the context of aeroelastic tailoring, the influence of external stores attached to the wing structure has to be considered during the preliminary aircraft design phases.
Quality, CQI, and reengineering in health services organizations.

Abstract Quality in health care is defined with a focus on satisfying customer needs. The contemporary management philosophies of continuous quality improvement (CQI) and reengineering are defined; attributes and applications of each are described. Criticism of reengineering appearing in the literature is presented. It is likely that CQI will remain a predominate management philosophy in health services, while reengineering may not endure in its form of radical change.
Reduced cardiac fructose 2,6 bisphosphate increases hypertrophy and decreases glycolysis following aortic constriction.

This study was designed to test whether reduced levels of cardiac fructose-2,6-bisphosphate (F-2,6-P2) exacerbates cardiac damage in response to pressure overload. F-2,6-P2 is a positive regulator of the glycolytic enzyme phosphofructokinase. Normal and Mb transgenic mice were subject to transverse aortic constriction (TAC) or sham surgery. Mb transgenic mice have reduced F-2,6-P2 levels, due to cardiac expression of a transgene for a mutant, kinase deficient form of the enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFK-2) which controls the level of F-2,6-P2. Thirteen weeks following TAC surgery, glycolysis was elevated in FVB, but not in Mb, hearts. Mb hearts were markedly more sensitive to TAC induced damage. Echocardiography revealed lower fractional shortening in Mb-TAC mice as well as larger left ventricular end diastolic and end systolic diameters. Cardiac hypertrophy and pulmonary congestion were more severe in Mb-TAC mice as indicated by the ratios of heart and lung weight to tibia length. Expression of α-MHC RNA was reduced more in Mb-TAC hearts than in FVB-TAC hearts. TAC produced a much greater increase in fibrosis of Mb hearts and this was accompanied by 5-fold more collagen 1 RNA expression in Mb-TAC versus FVB-TAC hearts. Mb-TAC hearts had the lowest phosphocreatine to ATP ratio and the most oxidative stress as indicated by higher cardiac content of 4-hydroxynonenal protein adducts. These results indicate that the heart’s capacity to increase F-2,6-P2 during pressure overload elevates glycolysis which is beneficial for reducing pressure overload induced cardiac hypertrophy, dysfunction and fibrosis.
Evidence for a negative conduction electron contribution to hyperfine fields in iron, cobalt and nickel from pressure dependence experiments☆

Abstract Results from previous pressure dependence studies of magnetization, ferromagnetic nuclear resonance and Mossbauer effect are used to support the hypothesis that conduction electron contributions to hyperfine fields in Fe, Co and Ni are negative.
Embedding simple machines to add novel dynamic functions to composites

One unique property of a machine-augmented composite (MAC) is its ability to convert a compressive force into a shear force, and vice versa, simply by the geometry of its angled sidewalls. The authors have discovered that a non-spinning ball dropped at a normal angle onto the MAC’s surface rebounds from that surface at an oblique angle and develops a significant rotational velocity. Through finite-element analyses, analytical study, and experiments, the magnitude and direction of the spin can be precisely controlled by tailoring the stiffness of the MAC through the properties and dimensions of its constituent materials.
ACAT1 deficiency increases cholesterol synthesis in mouse peritoneal macrophages.

Abstract Acyl-coenzyme A: cholesterol acyltransferase (ACAT) esterifies free cholesterol and stores cholesteryl esters in lipid droplets. Macrophage ACAT1 deficiency results in increased atherosclerotic lesion area in hyperlipidemic mice via disrupted cholesterol efflux, increased lipoprotein uptake, accumulation of intracellular vesicles, and accelerated apoptosis. The objective of this study was to determine whether lipid synthesis is affected by ACAT1. The synthesis, esterification, and efflux of new cholesterol were measured in peritoneal macrophages from ACAT1(−/−) mice. Cholesterol synthesis was increased by 134% ( p =0.001) in ACAT1(−/−) macrophages compared to wildtype macrophages. Increased synthesis resulted in a proportional increase in the efflux of newly synthesized cholesterol. Although the esterification of new cholesterol was reduced by 93% ( p
On robust solutions to uncertain monotone linear complementarity problems (LCPs) and their variants

Variational inequality and complementarity problems have found utility in modeling a range of optimization and equilibrium problems arising in engineering, economics, and the sciences. Yet, while there have been tremendous growth in addressing uncertainty in optimization, far less progress has been seen in the context of variational inequality problems, exceptions being the efforts to solve variational inequality problems with expectation-valued maps [1], [2]. Yet, in many instances, the goal lies in obtaining solutions that are robust to uncertainty. While the fields of robust optimization and control theory have made deep inroads into developing tractable schemes for resolving such concerns, there has been little progress in the context of variational problems. In what we believe is amongst the very first efforts to comprehensively address such problems in a distribution-free environment, we present an avenue for obtaining robust solutions to uncertain monotone affine complementarity problems defined over the nonnegative orthant. We begin with and mainly focus on showing that robust solutions to such problems can be tractably obtained through the solution of a single convex program. Importantly, we discuss how these results can be extended to account for uncertainty in the associated sets by generalizing the results to uncertain affine variational inequality problems defined over uncertain polyhedral sets.
Non-universalities in Supergravity Grand Unification

Non-universalities in the soft SUSY breaking parameters within grand unification are investigated. In general non-universalities contain effects of Planck physics and are sensitive to physics between the GUT scale and the Planck/string scale. The effect of the top Landau pole on the non-universalities in the Higgs sector are discussed. A class of models are investigated where it is shown that the non-universalities at the GUT scale depend upon on both the grand unification group and the particle spectrum in the post GUT region, different assumptions giving rise to different phenomena. Thus the sparticle spectrum at low energy will be sensitive not only to GUT physics but also to physics up to the string scale. The possibilities of experimentally probing the post GUT domain at LHC and at linear colliders using various sum rules is described.
Electron microscopy of t-allele synaptonemal complexes discloses no inversions.

The t complex of mice has been an enigma for over half a century1. The recessive mutations (tn) on chromosome 17 of the mouse have been characterized by four properties: interaction with the dominant mutation T (Brachyury) to cause tail-lessness, transmission ratio distortion in males, a series of homozygous lethal mutations, and cross-over suppression2–4. The last property has led to many studies of meiosis in t-allele-bearing males. Forejt found fewer chiasmata, the cytological correlate of crossing-over, in the region of t haplotypes5,6. Lyon et al.7 confirmed these results and suggested that chiasma suppression determined by t alleles is probably desynaptic but that electron microscopy would probably be needed to settle this point. We have now extended these observations by using a centromeric translocation and analysed synaptonemal complexes by electron microscopy to study t-haplotype pairing. We have found normal synaptonemal complexes without any evidence of inversions but detected early disjunction of the chromosome 17 homologues, supporting the idea of desynaptic chiasma suppression.
Photoinduced Electron Transfer in Covalently Linked 1,8-Naphthalimide/Viologen Systems

A series of polymethylene-linked 1,8-naphthalimide/viologen diads has been synthesized. The number of intervening methylenes was varied from 2 to 6. For comparison, a series of N-alkylpyridiniumyl-1,8-naphthalimide “parent” compounds was prepared and photophysically characterized. Relative to the parent compounds, the electronically excited singlet state of the 1,8-naphthalimide was found to be quenched by the covalently attached viologen. From Stern−Volmer analyses of the steady-state fluorescence spectra, along with the singlet-state lifetime of the pyridinium-substituted 1,8-naphthalimide, the rate constants for intramolecular quenching were calculated to range from 1.5 × 1010 s-1 (2 intervening methylenes) to 8.3 × 107 s-1 (6 intervening methylenes) in aqueous buffered solution. For comparison, the intermolecular reactivity of the excited singlet state of N-alkylpyridiniumyl-1,8-naphthalimides with methylviologen was assessed. In 0.5 M phosphate buffer (pH 7.0), the bimolecular rate constant was found...
Increased left ventricular mass and decreased left ventricular systolic function have independent pathways to ventricular arrhythmogenesis in coronary artery disease

Background Following myocardial infarction, individual patients can have wide variations in the extent of left ventricular systolic dysfunction (LVSD) and increased left ventricular (LV) mass. Both affect the risk for sudden cardiac death, but only LV ejection fraction is used for risk prediction. Objective The purpose of this study was to evaluate the independent as well as the additive contributions of increased LV mass and decreased LV ejection fraction to sudden cardiac death in the general population. Methods In the ongoing Oregon Sudden Unexpected Death Study, we studied consecutive SCD cases (n = 191) and coronary artery disease controls (n = 203) from the Portland, Oregon, metropolitan area (population approximately 1,000,000; 2002–2008). Comparisons of echocardiographic LV mass obtained prior and unrelated to sudden cardiac death (SCD) were conducted, and a logistic regression model was used to evaluate the relationship between SCD, severe LVSD, LV mass, and other relevant clinical variables. Results In a multivariate model, both severe LVSD and left ventricular hypertrophy (LVH) were associated with increased SCD risk (odds ratio [OR] 1.9, 95% confidence interval [CI] 1.1–3.2 for severe LVSD; OR 1.8, 95% CI 1.1–2.9 for LVH). In patients with coexisting severe LVSD and LVH, risk of SCD was additive (OR 3.5, 95% CI 1.7–7.2). In the same model, increased age, atrial fibrillation/flutter, elevated creatinine, and diabetes independently increased risk, and use of angiotensin receptor blockers attenuated risk. Conclusion Reduced LV ejection fraction and increased LV mass had independent and additive effects on risk of sudden death. Despite the significant overlap between the two conditions, these findings point toward the existence of independent mechanistic pathways for ventricular arrhythmias that occur due to LVSD and LVH.
Mammosomatotropes Are Abundant in Bovine Pituitaries: Influence of Gonadal Status

Mammosomatotropes--cells that secrete both GH and PRL--are a common pituitary cell type in a variety of mammalian species. Recently, immunogold electron microscopy was used to demonstrate that all acidophils (a generic term used here to denote cells which secrete GH and/or PRL) in cattle stain for both GH and PRL. This high degree of overlap, which is unique among the mammalian species examined in this regard, raises the question: do all acidophils actively release both hormones concurrently? In the present study, we addressed this question by employing reverse hemolytic plaque assays to measure GH and PRL release from individual bovine pituitary cells in culture in the presence of stimulatory secretagogues. Inconsistent with the previous reports on hormone storage, all bovine acidophils in gonad-intact and castrated males did not actively release both GH and PRL. In gonad-intact males approximately 9% of all pituitary cells released both hormones, whereas 21% released only GH and 45% PRL alone. In castrated males, mammosomatotropes comprised only 22% of the pituitary cell population, whereas GH-only cells accounted for 8% and PRL secretors 46%. This divergence in the relative proportions of GH-only cells and mammosomatotropes suggests that the hormonal milieu plays an important role in maintenance of the various acidophilic cell types. In addition, the reciprocal relationship between cells that released GH-only and dual hormone secretors in the two models studied supports the possibility that these cell types are functionally interconvertible.
Students' Interaction with Computer Representations: Analysis of Discourse in Laboratory Groups

Language use in student laboratory groups makes apparent students' conceptions in science, their interpretation of the activity or task, and the negotiation of the roles of the members. This article reports on a methodological approach to analyze student discourse systematically. Four Grade 12 lab groups working on microcomputer-based laboratories (MBL) are the focus of the study. The MBL experiences were used to help students link oscillatory motion to graphical representations. Study of student discourse reveals the role the computer plays in the group context and the ways that this context is shaped by the computer. Developing a better understanding of the role of the computer in student conversations suggests ways to fruitfully construct contexts for learning physics. © 1996 John Wiley & Sons, Inc.
Chronic hyperglycemia increases arterial low-density lipoprotein metabolism and atherosclerosis in cynomolgus monkeys

Diabetes mellitus confers a threefold to fivefold increased risk of mortality from vascular disease. The primary cause of this increased incidence of vascular disease is atherosclerosis, but the mechanisms accounting for the increase are unclear. Chronic hyperglycemia is a common feature of all forms of diabetes mellitus and may contribute greatly to the increased incidence of atherosclerosis, via promotion of both lipoprotein and tissue glycation, which may have atherogenic effects. The present study investigated the effect of chronic hyperglycemia on measures of low-density lipoprotein (LDL) metabolism and atherosclerosis in streptozotocin-induced diabetic (STZ-DM) and control cynomolgus monkeys after 6 months of study. Consistent with a chronic hyperglycemic state, diabetic monkeys had significant increases in glycated hemoglobin (GHb) and glycated plasma LDL concentrations, but had minimal changes in total plasma cholesterol (TPC) or triglyceride (TG) concentrations during the study. Forty-eight hours before necropsy, control and in vitro-glycated LDL were differentially radiolabeled and coinjected into diabetic and control monkeys. There was a significant increase in arterial LDL accumulation in femoral arteries from diabetic monkeys compared with controls, with similar trends in other arterial sites. The effect of LDL glycation on arterial LDL accumulation was minimal in both groups. Arterial segments from diabetic monkeys also had greater amounts of arterial cholesterol content compared with controls. Histomorphometric analyses showed that diabetic monkeys had significantly greater intimal areas in the femoral artery and abdominal aorta compared with controls. Diabetic monkeys also had reduced arterial remodeling, or compensation, in the femoral artery and abdominal aorta. However, there was no difference in advanced glycation end products (AGE) in arterial collagen between groups. In conclusion, experimentally induced diabetes mellitus increases arterial LDL accumulation and atherosclerosis extent in cynomolgus monkeys before changes in AGE formation. The increased atherogenesis may be due to changes in lipoproteins or direct effects of hyperglycemia on the artery wall.
Core polarization in inelastic proton scattering from 209Bi at 61 MeV

Abstract The differential cross sections for the excitation of the 0.90 MeV ( 2f 7 2 ) and 1.61 MeV ( 1i 13 2 ) single proton levels and the multiplet of states at 2.62 MeV in 209Bi have been measured with 61.2 MeV protons. The results of collective model calculations and microscopic model calculations with core polarization are compared with the data. It is found that L = 4, 6, and 8 core admixtures are important in the 0.90 MeV transition. The shape of the differential cross section for the 1.61 MeV excitation very clearly indicates that L = 3 transfer is dominant in this transition. An 8% admixture of the 13 2 + member of the 2.62 MeV multiplet in the 1i 13 2 single proton state is needed to explain the 1.61 MeV cross section. The cross section for the 2.62 MeV multiplet is consistent with the weak coupling model.
In vitro and ex vivo autoradiography of the NK-1 antagonist [3H]-LY686017 in Guinea pig brain

NK-1 receptor antagonists have shown potential for the clinical treatment of chemotherapy-induced nausea and vomiting, depression and alcoholism. In a recent study, we disclosed the potential for the NK-1 antagonist, LY686017, to treat alcoholism in a clinical population. To assess whether this compound could be utilized as a platform for a brain imaging ligand, we evaluated the binding of [³H]-LY686017 to sections of guinea pig in vitro. In these studies, [³H]-LY686017 bound with a distribution and pharmacology consistent with the NK-1 receptor. Using sections through the region of the caudate nucleus, we obtained a K(d) of 0.34 nM and a B(max) of 31.37 fmoles/mg tissue. Based on its high potency and low nonspecific binding in vitro, we initiated studies to evaluate the radioligand as a tool to measure in vivo receptor occupancy. In initial studies, 25 microCi of [³H]-LY686017 was administered via an indwelling jugular catheter and accumulation of radioactivity in the caudate (NK-1 containing tissue) and cerebellum (low NK-1 expression) were assessed. The ratios of caudate to cerebellum radioactivity were optimal 2 h after radioligand administration so this time point was used for subsequent studies. To assess the pharmacological specificity of the radioactivity accumulation, we administered various doses of Aprepitant, a potent NK-1 antagonists 1h prior to intravenous administration of [³H]-LY686017. Aprepitant produced a dose-dependent reduction in radioactivity in the caudate with an approximate 70% reduction at 10 mg/kg. To image NK-1 receptors, 100 microCi of [³H]-LY686017 was administered and the brains sectioned for autoradiography. In these studies, a characteristic distribution on NK-1 receptors was observed. Based on these results, LY686017 should serve as a suitable chemical platform for future imaging ligand development.
In vivo molecular-genetic imaging

Noninvasive in vivo molecular-genetic imaging has developed over the past decade and involves nuclear (PET, gamma camera), magnetic resonance, and in vivo optical imaging systems. Although three different imaging strategies - "direct," "indirect" and "surrogate" - are being used, most current in vivo molecular imaging strategies are "indirect" and involve the coupling of a "reporter gene" with a complimentary "reporter probe." Imaging the level of probe accumulation provides indirect information related to the level of reporter gene expression. Reporter gene constructs are driven by upstream promoter/enhancer elements; reporter gene expression can be "constitutive" leading to continuous transcription and used to identify the site of transduction and to monitor the level and duration of gene (vector) activity. Alternatively, reporter gene expression can be "inducible" leading to controlled gene expression. Controlled gene expression can be tissue-specific and/or responsive to the level of endogenous promoters and transcription factors. Several examples of imaging endogenous biological processes in animals using reporter constructs, radiolabeled probes and PET imaging are reviewed, including: 1) imaging transcriptional regulation (e.g., p53-dependent gene expression), 2) imaging weak promoters (cis- vs. trans-reporter configurations), 3) imaging post-transcriptional regulation of gene expression, 4) imaging protein-protein interactions. The development of versatile and sensitive assays that do not require tissue sampling will be of considerable value for monitoring molecular-genetic and cellular processes in animal models of human disease, as well as for studies in human subjects in the future. Non-invasive imaging of molecular-genetic and cellular processes will compliment established ex vivo molecular-biological assays that require tissue sampling, and will provide a spatial as well as a temporal dimension to our understanding of various diseases.
Biological rhythms and the behavior of populations of coupled oscillators

Abstract The impressive variety of biological rhythms leaves no doubt that autonomously periodic processes contribute to the coordination of life-processes. The question here raised is, “What modes of temporal organization—if any—could result from weak interactions in a population of innately oscillatory devices (e.g. electronic oscillators, secretory cells, spontaneously active neurons, or individual animals)?” By mathematical analysis, electronic experiments, and digital computer simulation, answers are found as functions of the nature of the periodic processes and the kind of interactions involved. For populations of “generalized relaxation oscillators”, threshold conditions are discovered for mutual synchronization in any of a variety of modes. It is proposed that self-entraining communities of this sort may exist within individual metazoan animals and plants as the basis of the observed diurnal coordination of their physiological process.
Overlapping resolution maps as an aid in parallel development thin-layer chromatography

Abstract A method is described for constructing overlapping resolution maps for thin-layer chromatography. The axes of the maps are time, length and binary solvent composition. These maps can be used to identify sets of compounds within a mixture such that each set is fully separated under appropriate conditions. The separation of a mixture of fifteen steroids is described, using this technique.
Nonuniqueness in theS-matrix reduction by means of the asymptotic condition — I

The reduction formulas forS-matrix elements derived by employing the asymptotic condition on interacting fields are studied for the case of the vertex function in a nonlocal form-factor theory for two interacting scalar fields with nonzero mass. It is shown in first-order perturbation theory that for physical values of the momenta one may especially replace the conventional step function appearing in the standard integral formulas by the modified step functionθ(x0—α|x|) with 0<α<k0/|k| wherek represents the four-momentum of the reduced particle in the rest frame of the other one. This means that for such modifications the world-line of the reduced particle but not the light cone is distinguished. However, it is found that the standard as well as the modified integral formulas are not well defined in the sense that they are equivalent to integrals over the energy whose integrands involve the product of a distribution with a nonregular function. This has the consequence that the analytic continuation of the reduction formulas leads to nonunique results. Concluding the local case is considered where the reduction formulas with the standard retarded commutator are distinguished. In a forthcoming paper some generalizations of the above results will be treated.
Consistent attending versus consistent responding in visual search: Task versus component consistency in automatic processing development

The current research examined whether the total processing, from stimulus to response, must be consistent for automatic processing to improve task performance. Consistent versus inconsistent attending and responding (i.e., response translation) were factorially combined. Results showed that the consistency of attending produced substantial practice effects. However, consistency of the motor response translation component did not affect the asymptotic performance level. The results indicate that automatic processing develops for consistent components of a task even when the entire task is not consistent.
GeneHuggers: database mining and application connectivity tools for subsequence analyses of the human genome.

UNLABELLED GeneHuggers is a collection of program modules that enables precise selection of subsequence regions from records of the RefSeq human genome database. Subsequence regions can be selected based on diverse criteria, including feature addresses, annotations from LocusLink and UniGene, and results obtained from analyses with homologous subsequence detection programs. GeneHuggers provides functionality to the UNIX operating system that allows customized bioinformatics program development. AVAILABILITY GeneHuggers source code is available under the GNU general public license and can be downloaded from ftp://ftp.scripps.edu/pub/genehuggers/gh.tar.gz
Isosteric heat of sorption of CO2 in poly(ethylene terephthalate)

Abstract Sorption isotherms for carbon dioxide in poly(ethylene terephthalate) have been measured at 35–55°C. The isotherms were measured gravimetrically on a Mettler Thermoanalyzer-1 from vacuum to 1 atmosphere. The sorption data were used to generate sorption isotherms from which the isosteric heat of sorption of CO2 in PET was determined. At 45°C the isosteric heat of sorption increases from −10 kcal/mole at a concentration of 0.5 cm3 (STP)/cm3 (polymer) to −8 kcal mole−1 at a concentration of 1.5 cm3 (STP)/cm3 (polymer). It has been reported in the literature that the isosteric heat of sorption for this system decreased through a minimum before increasing with increasing concentration. Our measurement of the low-pressure sorption isotherms shows that this is not the case.
Cell proliferation and vascularization in mouse models of pituitary hormone deficiency

Mutations in the transcription factors PIT1 (pituitary transcription factor 1) and PROP1 (prophet of Pit1) lead to pituitary hormone deficiency and hypopituitarism in mice and humans. To determine the basis for this, we performed histological analysis of Pit1- and Prop1-deficient dwarf mouse pituitaries throughout fetal and postnatal development. Pit1-deficient mice first exhibit pituitary hypoplasia after birth, primarily caused by reduced cell proliferation, although there is some apoptosis. To determine whether altered development of the vascular system contributes to hypopituitarism, we examined vascularization from embryonic d 14.5 and throughout development. No obvious differences in vascularization are evident in developing Pit1-deficient pituitaries. In contrast, the Prop1-deficient mouse pituitaries are poorly vascularized and dysmorphic, with a striking elevation in apoptosis. At postnatal d 11, apoptosis-independent caspase-3 activation occurs in thyrotropes and somatotropes of normal but not mutant pituitaries. This suggests that Prop1 and/or Pit1 may be necessary for caspase-3 expression. These studies provide further insight as to the mechanisms of Prop1 and Pit1 action in mice.
Symplectic Integrators with Complex Time Steps

Symplectic integrators are a popular tool applied to a variety of numerical problems. Many symplectic methods are known, but those higher than second order must include some substeps that travel backward compared with the main integration. To compensate for this, some substeps must have large coefficients. This produces large error terms and reduces the efficiency of high-order symplectic algorithms. The constraint equations for the substeps of high-order algorithms often have complex solutions in addition to the known real ones. The complex solutions typically generate symplectic integrators with small substeps, so these algorithms have substantially smaller error terms than conventional algorithms. This makes them more efficient in principle. Here third-, fourth-, and sixth-order algorithms are developed and tested for problems in which the Hamiltonian is split into kinetic and potential energy terms, and also for perturbed Kepler problems. In addition, symplectic correctors are developed for the third- and fourth-order methods. It is shown that complex integrators with leading error terms that have strictly imaginary coefficients effectively behave as if they are 1 order higher than expected.
On L∞ norms of holomorphic cusp forms

Abstract In this short note, we get the precise bound for holomorphic cusp forms with respect to the weight just by Weil bound.
Predictive smooth pursuit of complex two-dimensional trajectories in monkey: Component interactions

Smooth pursuit eye movements were studied in monkeys tracking target spots that moved two-dimensionally. Complex target trajectories were created by applying either two or three sinusoids to horizontal and vertical axes in various combinations. The chance of observing predictable performance was increased by repeated training on each trajectory. Data analyses were based upon repeated presentations of each trajectory within sessions and on successive days. We wished to determine how accurately monkeys could pursue targets moving along these trajectories and to observe interactions among frequency components. At intermediate frequencies, tracking performance was smooth and consistent during repeated presentations with saccadic corrections that were well integrated with smooth pursuit. The mean gain for eight different sum-of-sines trajectories was 0.83 and the mean magnitude (absolute value) of the phase error was 6°. In light of the long delays that have been associated with the processing of visual information, these values indicate that the monkeys were pursuing predictively. Five factors influenced predictive pursuit performance: (1) there was a decline in performance with increasing frequency; (2) horizontal pursuit was better than vertical pursuit; (3) high-frequency components were tracked with higher gains and phase lags, while lower-frequency components were tracked with lower gains and phase leads; (4) the gain of sinusoidal pursuit was always reduced when a second sinusoid was applied to the same axis or, to a lessor extent, when a second sinusoid of higher frequency was applied to the orthogonal axis; (5) the phase of sinusoidal pursuit shifted from a phase lag to a phase lead when combined with a second sinusoid of higher frequency, but was not affected by the addition of a lower-frequency sinusoid. Findings 1 and 2 confirm, in monkeys, results reported for humans, and 3 extends to monkeys and to two-dimensional pursuit results based upon human subjects. All of these findings demonstrate that complex predictive tracking is controlled by a nonlinear and nonhomogeneous system that uses predictive strategies in concert with feedback control to generate good pursuit.
Effect of Turbulence Intensity and Periodic Unsteady Wake Flow Condition on Boundary Layer Development, Separation, and Re-Attachment Over the Separation Bubble Along the Suction Surface of a Low Pressure Turbine Blade

The paper experimentally investigates the individual and combined effects of periodic unsteady wake flows and freestream turbulence intensity (FSTI) on flow separation along the suction surface of a low pressure turbine blade. The experiments were carried out at a Reynolds number of 110,000 based on the suction surface length and the cascade exit velocity. The experimental matrix includes freestream turbulence intensities of 1.9%, 3.0%, 8.0%, 13.0% and three different unsteady wake frequencies with the steady inlet flow as the reference configuration. Detailed boundary layer measurements are performed along the suction surface of a highly loaded turbine blade with a separation zone. Particular attention is paid to the aerodynamic behavior of the separation zone at different FSTIs at steady and periodic unsteady flow conditions. The objective of the research is (a) to quantify the effect of FSTIs on the dynamics of the separation bubble at steady inlet flow condition, and (b) to investigate the combined effects of FSTI and the unsteady wake flow on the behavior of the separation bubble. The experimental investigations were performed on a large scale, subsonic unsteady turbine cascade research facility at the Turbomachinery Performance and Flow Research Laboratory (TPFL) of Texas A&M University.Copyright © 2006 by ASME
An ecoregion approach to mercury bioaccumulation by fish in reservoirs

Three Oregon reservoirs were evaluated for environmental parameters affecting mercury (Hg) dynamics and bioaccumulation in fish using an ecoregion approach. Ecoregions are distinguished by topography, geology, soil type and composition, and land use patterns. We examined: pH, dissolved oxygen, hardness, conductivity and concentration of Hg ([Hg]) in water; and complexing agent concentrations, organic content, inorganic and organic [Hg] in sediments; and [Hg] in three fish species. [Hg] in water was below detection (0.1 μg/L) in most water samples from the three reservoirs; in samples above detection, we reasoned that Hg was predominantly in the particulate fraction. Hg in sediment was only found consistently in the inorganic state; organic mercury was below detection (0.2 ng/g) in 83% of sediment samples. Muscle [Hg] in fish over 4 years old was above the FDA limit of 1.0 μg/g wet weight, and more than 90% of the Hg in all fish was organic mercury. [Hg] in lateral muscle was similar between smallmouth bass (Micropterus dolomieu) in Owyhee Reservoir and largemouth bass (Micropterus salmoides) in Cottage Grove Reservoir; rainbow trout (Salmo gairdneri) from Ochoco Reservoir had significantly lower levels of Hg. It is concluded that, although ecoregion parameters alone do not explain mercury dynamics, they may influence the methylation rate in areas of similar Hg loading rates.
Antioxidant Nutrients and Pulmonary Function: The Third National Health and Nutrition Examination Survey (NHANES III)

Recent studies of chronic obstructive pulmonary disease have raised interest in its relation to nutrition. Several dietary antioxidants have been positively associated with lung function in healthy, general population samples. This study considered the separate and joint effects of vitamin C, vitamin E, beta-carotene, and selenium intake and used both dietary assessment and serum biomarkers of antioxidant status. The authors used data from the Third National Health and Nutrition Examination Survey comprising a sample representative of the US population in 1988-1994 (n = 18,162 subjects aged > or =17 years). Multiple linear regression analysis examined the separate and joint effects of the antioxidants on the ratio of forced expiratory volume in the first second (FEV1)/height2 adjusted for covariates. Each of the dietary and serum antioxidant nutrients was significantly associated with FEV1. When they were considered simultaneously (dietary and serum variables considered in separate models), independent associations were observed for most nutrients. Serum beta-carotene was less positively associated with FEV1 in smokers than nonsmokers, while serum selenium had a stronger positive association with FEV1 in smokers. The authors found that higher levels of antioxidant nutrients are associated with better lung function. The finding that the antioxidants differ in both their overall association with lung function and in whether this association varies by smoking status has implications for further research.
The association between adaptive and cognitive deficits in geriatric chronic schizophrenic patients

Cognitive impairments have been shown to predict impairments in adaptive functioning in patients with chronic schizophrenia and to be more predictive of overall outcome than positive or negative symptoms of the illness. Both adaptive and cognitive impairments are multidimensional, and it is possible that correlations between these domains may be limited to certain aspects of these functions. In this study, 208 geriatric patients with chronic schizophrenia were examined with a cognitive battery and assessed with a structured scale to determine the extent of their adaptive functions. Instrumental and social skills deficits were more strongly correlated with cognitive impairments than with the severity of undercontrolled behavior. Each of the cognitive measures was correlated with global social-adaptive deficits, with minimal variation in the magnitude of correlations. These results suggest that interventions should be individually targeted to cognitive-adaptive impairments and undercontrolled behavior.
Serum lipid changes during progressive hyperthermia

Abstract Serum total lipids and fatty acids decrease in cats during progressive hyperthermia. Evidence is presented that the decreases represent an effect of elevated temperature on metabolism rather than a change secondary to hypocapnia, as is the case with lactate and pyruvate.
Firing Squads and Fine-Tuning: Sober on the Design Argument

AbstractElliott Sober has recently argued that the cosmological design argument is unsound, since our observation of cosmic fine-tuning is subject to an observation selection effect (OSE). I argue ...
Building real-time imprecise computations in Ada

The model of imprecise computation is an effective way to structure programs that must always meet deadlines in real-time systems. Under severe time constraints, an imprecise computation may return an imprecise, though correct value. In this way, timing faults can be avoided. In this paper, we describe two implementations of an imprecise computation package in Ada. We have also studied their performance differences under different system and programming environments. Finally, we present our experience in implementing real-time applications using Ada.
Effective photodissociation cross sections for molecular oxygen and nitric oxide in the Schumann-Runge bands

Accurate calculations of the atmospheric opacity and the photodissociation rate of molecular oxygen in the Schumann-Runge bands (175-205) are necessary for modeling chemistry in the terrestrial upper atmosphere. The present investigation is concerned with a single simple parameterization of effective cross sections which can be used to calculate both O2 opacity and dissociation rates. Use is made of a zenith angle dependent factor which accounts for variations shown in detailed calculations. The conducted analysis is based on the results of Frederick and Hudson (1980). Attention is given to molecular oxygen effective cross sections and nitric oxide effective cross sections. It is found that the depth of the atmosphere to which solar radiation in the 175-200 nm spectral region penetrates is a sensitive function of the rotational line widths in the Schumann-Runge bands. The oscillator strength for each band measures the cross section integrated over the band while the line width determine how the absorption is distributed in wavenumber.
Behavioural adaptations of cryptic moths. III: Resting attitudes of two bark-like species, Melanophia Canadaria and Catocala ultronia

Summary Two bark-like moth species were tested for resting attitude preferences in an experimental apparatus which allowed a choice between backgrounds having vertically or horizontally oriented surface irregularities. The moths were exposed to either the tactile and visual clues associated with these backgrounds, or to the visual clues alone. When exposed to the tactile and visual stimuli of the backgrounds, a geometrid, with prominent transverse markings, rested at right angles to the surface irregularities (whatever their orientation). Under these same conditions, a noctuid, with prominent longitudinal markings, rested in a head-down attitude, and preferred the vertically oriented surface irregularities. When exposed to only the visual stimuli of these backgrounds, the geometrid exhibited a random distribution of resting attitudes which were unrelated to the background patterns. The noctuid under these conditions maintained its head-down attitude, but lost its preference for the vertically oriented background patterns. On the basis of these results, two mechanisms for effecting an alignment of moth and background patterns are proposed.
Haptic Illusion: Apparent Elongation of a Disk Rotated between the Fingers

A disk (coin) turned end over end between thumb and forefinger feels longer to the turning hand. The illusion grows rapidly for 30 seconds but does not become asymptotic within 60 seconds. The illusion increases with coin size and turning rate, and is independent of holding pressure. It appears to involve illusory mechanisms in both hands.
Axially distorted 3–3 piezoelectric composites for hydrophone applications

Abstract Application of reticulated ceramic technology to the fabrication of 3–3 lead zirconate-titanate (PZT)/Spurr epoxy composites has been investigated. Use of this technology provides a substantial improvement in manufacturability over other methods. Directional distortion of the ceramic structure to enhance the composite's hydrostatic response is also possible. Composite fabrication is described and the effects of distortion on the piezoelectric properties are presented. The results for K33 and g33 are found to be comparable to other 3–3 PZT/epoxy composites while d33 and hydrostatic gh are reduced with density.
FGF signaling establishes the anterior border of the Ciona neural tube

The Ciona tadpole is constructed from simple, well-defined cell lineages governed by provisional gene networks that have been defined via extensive gene disruption assays. Here, we examine the patterning of the anterior neural plate, which produces placodal derivatives such as the adhesive palps and stomodeum, as well as the sensory vesicle (simple brain) of the Ciona tadpole. Evidence is presented that the doublesex-related gene DMRT is expressed throughout the anterior neural plate of neurulating embryos. It leads to the activation of FoxC and ZicL in the palp placode and anterior neural tube, respectively. This differential expression depends on FGF signaling, which inhibits FoxC expression in the anterior neural tube. Inhibition of FGF signaling leads to expanded expression of FoxC, the loss of ZicL, and truncation of the anterior neural tube.
Insertion Devices, Future Developments, Limitations

The first generation of insertion devices having reached maturity (or almost), it is appropriate to survey directions along which new developments are expected. These include: Beam cooling with undulators, elementary particle physics with wigglers and undulators, microwigglers, dynamic (i.e. electromagnetic) insertion devices, bunched electron beam wigglers, time compression of photon pulses, the confinement and compression of radiation, optimized insertion devices, damage resistant optics, photon bunch contouring, and the rebunching of electron beams by phase switching. A theorem will be mentioned which limits the number of photons emitted by a relativistic electron (e.g. one passing through an insertion device).
Oxidite or “Meteoritic Shale,” Terrestrialization, and Terrestrialite

The term oxidite is proposed to replace the synonyms meteoritic shale and iron-shale. Terrestrialization means the terrestrial transformation of a meteorite into something that can no longer be properly regarded as being a meteorite, and terrestrialite signifies the product of that transformation. Both oxidite and meteorodes (defined in n. (3) to the paper) are varieties of terrestrialite.
Effect of Variable Speed Wind Turbine Generator on Stability of a Weak Grid

In this paper, we illustrate the effect of adding a hypothetical 100-MW doubly fed induction generator (DFIG) wind power plant to a weak transmission system. The effects of various wind plant load factors (100, 60 and 25% of nameplate rating) are investigated. System performance is compared to a 100-MW conventional synchronous generator interconnected at the same location. The conventional generator is installed some distance away. The simulations demonstrated that DFIG generators provide a good damping performance under these conditions. These results support the conclusion that modern wind power plants, equipped with power electronics and low-voltage ride-through capability, can be interconnected to weak power grids without reducing stability. To conduct the studies, we selected an area of the Western Electricity Coordinating Council power system that is electrically far from major generation centers and is weakly connected to the bulk transmission system. The area contains large motor loads. We observed the dynamic response of large motors in the vicinity, especially their ability to ride through fault events. The studies were conducted using positive sequence phasor time-domain analysis