752 research outputs found

    Non-linear Pattern Matching with Backtracking for Non-free Data Types

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    Non-free data types are data types whose data have no canonical forms. For example, multisets are non-free data types because the multiset {a,b,b}\{a,b,b\} has two other equivalent but literally different forms {b,a,b}\{b,a,b\} and {b,b,a}\{b,b,a\}. Pattern matching is known to provide a handy tool set to treat such data types. Although many studies on pattern matching and implementations for practical programming languages have been proposed so far, we observe that none of these studies satisfy all the criteria of practical pattern matching, which are as follows: i) efficiency of the backtracking algorithm for non-linear patterns, ii) extensibility of matching process, and iii) polymorphism in patterns. This paper aims to design a new pattern-matching-oriented programming language that satisfies all the above three criteria. The proposed language features clean Scheme-like syntax and efficient and extensible pattern matching semantics. This programming language is especially useful for the processing of complex non-free data types that not only include multisets and sets but also graphs and symbolic mathematical expressions. We discuss the importance of our criteria of practical pattern matching and how our language design naturally arises from the criteria. The proposed language has been already implemented and open-sourced as the Egison programming language

    Blood pressure and blood lead concentration in bus drivers.

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    San Francisco bus drivers have an increased prevalence of hypertension. This study examined relationships between blood lead concentration and blood pressure in 342 drivers. The analysis reported in this study was limited to subjects not on treatment for hypertension (n = 288). Systolic and diastolic pressures varied from 102 to 173 mm Hg and from 61 to 105 mm Hg, respectively. The blood lead concentration varied from 2 to 15 micrograms/dL. The relationship between blood pressure and the logarithm of blood lead concentration was examined using multiple regression analysis. Covariates included age, body mass index, sex, race, and caffeine intake. The largest regression coefficient relating systolic blood pressure and blood lead concentration was 1.8 mm Hg/ln (micrograms/dL) [90% C. I., -1.6, 5.3]. The coefficient for diastolic blood pressure was 2.5 mm Hg/ln (micrograms/dL) [90% C. I., 0.1, 4.9]. These findings suggest effects of lead exposure at lower blood lead concentrations than those concentrations that have previously been linked with increases in blood pressure

    Phonon drag thermopower and weak localization

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    Previous experimental work on a two-dimensional (2D) electron gas in a Si-on-sapphire device led to the conclusion that both conductivity and phonon drag thermopower SgS^g are affected to the same relative extent by weak localization. The present paper presents further experimental and theoretical results on these transport coefficients for two very low mobility 2D electron gases in δ\delta-doped GaAs/Gax_xAl1x_{1-x}As quantum wells. The experiments were carried out in the temperature range 3-7K where phonon drag dominates the thermopower and, contrary to the previous work, the changes observed in the thermopower due to weak localization were found to be an order of magnitude less than those in the conductivity. A theoretical framework for phonon drag thermopower in 2D and 3D semiconductors is presented which accounts for this insensitivity of SgS^g to weak localization. It also provides transparent physical explanations of many previous experimental and theoretical results.Comment: 19 page Revtex file, 3 Postscript figur

    Effect of Cyclooxygenase(COX)-1 and COX-2 inhibition on furosemide-induced renal responses and isoform immunolocalization in the healthy cat kidney

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    BACKGROUND: The role of cyclooxygenase(COX)-1 and COX-2 in the saluretic and renin-angiotensin responses to loop diuretics in the cat is unknown. We propose in vivo characterisation of isoform roles in a furosemide model by administering non-steroidal anti-inflammatory drugs (NSAIDs) with differing selectivity profiles: robenacoxib (COX-2 selective) and ketoprofen (COX-1 selective). RESULTS: In this four period crossover study, we compared the effect of four treatments: placebo, robenacoxib once or twice daily and ketoprofen once daily concomitantly with furosemide in seven healthy cats. For each period, urine and blood samples were collected at baseline and within 48 h of treatment starting. Plasma renin activity (PRA), plasma and urinary aldosterone concentrations, glomerular filtration rate (GFR) and 24 h urinary volumes, electrolytes and eicosanoids (PGE(2), 6-keto-PGF1(α,) TxB(2)), renal injury biomarker excretions [N-acetyl-beta-D-glucosaminidase (NAG) and Gamma-Glutamyltransferase] were measured. Urine volume (24 h) and urinary sodium, chloride and calcium excretions increased from baseline with all treatments. Plasma creatinine increased with all treatments except placebo, whereas GFR was significantly decreased from baseline only with ketoprofen. PRA increased significantly with placebo and once daily robenacoxib and the increase was significantly higher with placebo compared to ketoprofen (10.5 ± 4.4 vs 4.9 ± 5.0 ng ml(−1) h(−1)). Urinary aldosterone excretion increased with all treatments but this increase was inhibited by 75 % with ketoprofen and 65 % with once daily robenacoxib compared to placebo. Urinary PGE(2) excretion decreased with all treatments and excretion was significantly lower with ketoprofen compared to placebo. Urinary TxB(2) excretion was significantly increased from baseline only with placebo. NAG increased from baseline with all treatments. Immunohistochemistry on post-mortem renal specimens, obtained from a different group of cats that died naturally of non-renal causes, suggested constitutive COX-1 and COX-2 co-localization in many renal structures including the macula densa (MD). CONCLUSIONS: These data suggest that both COX-1 and COX-2 could generate the signal from the MD to the renin secreting cells in cats exposed to furosemide. Co-localization of COX isoenzymes in MD cells supports the functional data reported here. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12917-015-0598-z) contains supplementary material, which is available to authorized users

    Pathways to health: a framework for health-focused research and practice

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    Public health research and practice is faced with three problems: 1) a focus on disease instead of health, 2) consideration of risk factor/disease relationships one at a time, and 3) attention to individuals with limited regard for the communities in which they live. We propose a framework for health-focused research and practice. This framework encompasses individual and community pathways to health while incorporating the dynamics of context and overall population vulnerability and resilience. Individual pathways to health may differ, but commonalities will exist. By understanding these commonalities, communities can work to support health-promoting pathways in addition to removing barriers. The perspective afforded by viewing health as a dynamic process instead of as a collection of risk factors and diseases expands the number of approaches to improving health globally. Using this approach, multidisciplinary research teams working with active community participants have the potential to reshape health and intervention sciences

    Ranking ligand affinity for the DNA minor groove by experiment and simulation

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    The structural and thermodynamic basis for the strength and selectivity of the interactions of minor-groove binders (MGBs) with DNA is not fully understood. In 2003 we reported the first example of a thiazole containing MGB that bound in a phase shifted pattern that spanned 6 base-pairs rather than the usual 4 (for tricyclic distamycin-like compounds). Since then, using DNA footprinting, nuclear magnetic resonance spectroscopy, isothermal titration calorimetry and molecular dynamics, we have established that the flanking bases around the central 4 being read by the ligand have subtle effects on recognition. We have investigated the effect of these flanking sequences on binding and the reasons for the differences and established a computational method to rank ligand affinity against varying DNA sequences

    ExoMol line lists - XLIV. IR and UV line list for silicon monoxide (SiO)

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    A new silicon monoxide (28Si16O) line list covering infrared, visible and ultraviolet regions called SiOUVenIR is presented. This line list extends the infrared EBJT ExoMol line list by including vibronic transitions to the A 1Π and E 1Σ+ electronic states. Strong perturbations to the A 1Π band system are accurately modelled through the treatment of 6 dark electronic states: C 1Σ−, D 1Δ, a 3Σ+, b 3Π, e 3Σ− and d 3Δ. Along with the X 1Σ+ ground state, these 9 electronic states were used to build a comprehensive spectroscopic model of SiO using a combination of empirical and ab initio curves, including the potential energy (PE), spin-orbit (SO), electronic angular momentum (EAM) and (transition) dipole moment curves. The ab initio PE and coupling curves, computed at the multireference configuration interaction (MRCI) level of theory, were refined by fitting their analytical representations to 2617 experimentally derived SiO energy levels determined from 97 vibronic bands belonging to the X–X, E–X and A–X electronic systems through the MARVEL procedure. 112 observed forbidden transitions from the C–X, D–X, e–X, and d–X bands were assigned using our predictions, and these could be fed back into the MARVEL procedure. The SiOUVenIR line list was computed using published ab initio transition dipole moments for the E–X and A–X bands; the line list is suitable for temperatures up to 10 000 K and for wavelengths longer than 140 nm. SiOUVenIR is available from www.exomol.com and the CDS database

    ExoMol line lists - XLIV. IR and UV line list for silicon monoxide (SiO)

    Get PDF
    A new silicon monoxide (28Si16O) line list covering infrared, visible and ultraviolet regions called SiOUVenIR is presented. This line list extends the infrared EBJT ExoMol line list by including vibronic transitions to the A 1Π and E 1Σ+ electronic states. Strong perturbations to the A 1Π band system are accurately modelled through the treatment of 6 dark electronic states: C 1Σ−, D 1Δ, a 3Σ+, b 3Π, e 3Σ− and d 3Δ. Along with the X 1Σ+ ground state, these 9 electronic states were used to build a comprehensive spectroscopic model of SiO using a combination of empirical and ab initio curves, including the potential energy (PE), spin-orbit (SO), electronic angular momentum (EAM) and (transition) dipole moment curves. The ab initio PE and coupling curves, computed at the multireference configuration interaction (MRCI) level of theory, were refined by fitting their analytical representations to 2617 experimentally derived SiO energy levels determined from 97 vibronic bands belonging to the X–X, E–X and A–X electronic systems through the MARVEL procedure. 112 observed forbidden transitions from the C–X, D–X, e–X, and d–X bands were assigned using our predictions, and these could be fed back into the MARVEL procedure. The SiOUVenIR line list was computed using published ab initio transition dipole moments for the E–X and A–X bands; the line list is suitable for temperatures up to 10 000 K and for wavelengths longer than 140 nm. SiOUVenIR is available from www.exomol.com and the CDS database

    Spitting Performance Parameters and Their Biomechanical Implications in the Spitting Spider, Scytodes thoracica

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    Spitting spiders Scytodes spp. subdue prey by entangling them at a distance with a mixture of silk, glue, and venom. Using high-speed videography and differential interference contrast microscopy, the performance parameters involved in spit ejection by Scytodes thoracica (Araneae, Scytodidae) were measured. These will ultimately need to be explained in biomechanical and fluid dynamic terms. It was found that the ejection of “spit” from the opening of the venom duct (near the proximal end of the fang) was orderly. It resulted in a pattern that scanned along a lateral-medial axis (due to fang oscillations) while traversing from ventral to dorsal (due to cheliceral elevation). Each lateral-to-medial sweep of a fang produced silk-borne beads of glue that were not present during each subsequent medial-to-lateral sweep. The ejection of “spit” was very rapid. A full scan (5–57 fang cycles, one upsweep of a chelicera) typically occupied less than 30 ms and involved fang oscillations at 278–1781 Hz. Ejection velocities were measured as high as 28.8 m/s. The “spit” was contractile. During the 0.2 s following ejection, silk shortened by 40–60% and the product of a full scan by both of the chelicerae could exert an aggregate contractile force of 0.1 – 0.3 mN. Based on these parameters, hypotheses are described concerning the biomechanical and fluid dynamic processes that could enable this kind of material ejection
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