bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Real Number Structure that is Effectively Categorical
Authors: Hertling Peter 
Published: November 2010

AbstractOn countable structures computability is usually introduced via numberings. For uncountable structures whose cardinality does not exceed the cardinality of the continuum the same can be done via representations. Which representations are appropriate for doing real number computations? We show that with respect to computable equivalence there is one and only one equivalence class of representations of the real numbers which make the basic operations and the infinitary normed limit operator computable. This characterizes the real numbers in terms of the theory of effective algebras or computable structures, and is reflected by observations made in real number computer arithmetic. Demanding computability of the normed limit operator turns out to be essential: the basic operations without the normed limit operator can be made computable by more than one class of representations. We also give further evidence for the well‐known non‐appropriateness of the representation to some basebby proving that strictly less functions are computable with respect to these representations than with respect to a standard representation of the real numbers. Furthermore we consider basic constructions of representations and the countable substructure consisting of the computable elements of a represented, possibly uncountable structure. For countable structures we compare effectivity with respect to a numbering and effectivity with respect to a representation. Special attention is paid to the countable structure of the computable real numbers.
Distributive Lattices with a Negation Operator
Authors: Celani Sergio Arturo 
Published: November 2010

AbstractIn this note we introduce and study algebras (L, V, Λ, ⌝, 0,1) of type (2, 2,1,1,1) such that (L, V, ⌝, 0,1) is a bounded distributive lattice and ⌝ is an operator that satisfies the condition ⌝ (a V b) = a ⌝ b and ⌝ 0 = 1. We develop the topological duality between these algebras and Priestley spaces with a relation. In addition, we characterize the congruences and the subalgebras of such an algebra. As an application, we will determine the Priestley spaces of quasi‐Stone algebras.
Stability and General Logics
Authors: Hyttinen Tapani 
Published: November 2010

AbstractIn this paper we make an attempt to study classes of models by using general logics. We do not believe that Lww is always the best logic for analyzing a class of models. Let K be a class of models and L a logic. The main assumptions we make about K and C are that K has the L‐amalgamation property and, later in the paper, that K does not omit L‐types. We show that, if modified suitably, most of the results of stability theory hold in this context. The main difference is that existentially closed models of K play the role that arbitrary models play in traditional stability theory. We prove e. g. a structure theorem for the class of existentially closed models of K assuming that K is a trivial superstable class with ndop.
Partition Complete Boolean Algebras and Almost Compact Cardinals
Authors: Jipsen Peter , Rose Henry 
Published: November 2010

AbstractFor an infinite cardinal K a stronger version of K‐distributivity for Boolean algebras, called k‐partition completeness, is defined and investigated (e. g. every K‐Suslin algebra is a K‐partition complete Boolean algebra). It is shown that every k‐partition complete Boolean algebra is K‐weakly representable, and for strongly inaccessible K these concepts coincide. For regular K ≥ u, it is proved that an atomless K‐partition complete Boolean algebra is an updirected union of basic K‐tree algebras. Using K‐partition completeness, the concept of γ‐almost compactness is introduced for γ ≥ K. For strongly inaccessible K we show that K is K‐almost compact iff K is weakly compact, and if K is 2K‐almost compact, then K is measurable. Further K is strongly compact iff it is γ‐almost compact for all γ ≥ K.
Étude constructive de problèmes de topologie pour les réels irrationnels
Authors: Khalouani Mohamed , Labhalla Salah , Lombardi Et Henri 
Published: November 2010

AbstractWe study in a constructive manner some problems of topology related to the set Irr of irrational reals. The constructive approach requires a strong notion of an irrational number; constructively, a real number is irrational if it is clearly different from any rational number. We show that the set Irr is one‐to‐one with the set Dfc of infinite developments in continued fraction (dfc). We define two extensions of Irr, one, called Dfc1, is the set of dfc of rationals and irrationals preserving for each rational one dfc, the other, called Dfc2, is the set of dfc of rationals and irrationals preserving for each rational its two dfc. We introduce six natural distances over Irr wich we denote by dfc0, dfc1, dfc2, d, dmir and dcut. We show that only the four distances dfco, dfc1, d and dmir among the six make Irr a complete metric space. The last distances define in Irr the same topology in a constructive sens. We study further the set Dfc1 in which we show that the irrationals constitute a closed subset. Finally, we make a particular study of the completion Dfc2 of Dfc for the two equivalent metrics dfc2 and dcut.
On MODkP Counting Degrees
Authors: Ozaki Masamitsu , Shinoda Juichi 
Published: November 2010

AbstractFor a prime k, the embeddability of finite lattices are discussed for various kind of the MODkP degrees of recursive sets. In particular, all finite lattices are embeddable into the MODkP Turing degrees, whereas the non distributive lattice M3 is embeddable into the MOD2P many‐one degrees but N5 is not.
Strong Cardinals and Sets of Reals in Lω1(ℝ)
Authors: Schindler Ralf‐Dieter 
Published: November 2010

AbstractWe generalize results of [3] and [1] to hyperprojective sets of reals, viz. to more than finitely many strong cardinals being involved. We show, for example, that if every set of reals in Lω (ℝ) is weakly homogeneously Souslin, then there is an inner model with an inaccessible limit of strong cardinals.
On the Finite Model Property of Intuitionistic Modal Logics over MIPC
Authors: Aoto Takahito , Shirasu Hiroyuki 
Published: November 2010

AbstractMIPC is a well‐known intuitionistic modal logic of Prior (1957) and Bull (1966). It is shown that every normal intuitionistic modal logicLover MIPC has the finite model property wheneverLis Kripke‐complete and universal.
Sémantique algébrique ďun système logique basé sur un ensemble ordonné fini
Authors: Nour Abir 
Published: November 2010

AbstractIn order to modelize the reasoning of an intelligent agent represented by a poset T, H. Rasiowa introduced logic systems called “Approximation Logics”. In these systems a set of constants constitutes a fundamental tool. In this papers, we consider logic systems called L′T without this kind of constants but limited to the case where T is a finite poset. We prove a weak deduction theorem. We introduce also an algebraic semantics using Hey ting algebra with operators. To prove the completeness theorem of the L′T system with respect to the algebraic semantics, we use the method of H. Rasiowa and R. Sikorski for first order logic. In the propositional case, a corollary allows us to assert that it is decidable to know “if a propositional formula is valid”. We study also certain relations between the L′T logic and the intuitionistic and classical logics.
Approaches to Effective Semi‐Continuity of Real Functions
Authors: Zheng Xizhong , Brattka Vasco , Weihrauch Klaus 
Published: November 2010

AbstractFor semi‐continuous real functions we study different computability concepts defined via computability of epigraphs and hypographs. We call a real function f lower semi‐computable of type one, if its open hypograph hypo(f) is recursively enumerably open in dom(f) × ℝ; we call f lower semi‐computable of type two, if its closed epigraph Epi(f) is recursively enumerably closed in dom(f) × ℝ; we call f lower semi‐computable of type three, if Epi(f) is recursively closed in dom(f) × ℝ. We show that type one and type two semi‐computability are independent and that type three semi‐computability plus effectively uniform continuity implies computability, which is false for type one and type two instead of type three. We show also that the integral of a type three semi‐computable real function on a computable interval is not necessarily computable.
Can You Add Power‐Sets to Martin‐Lof's Intuitionistic Set Theory?
Authors: Maietti Maria Emilia , Valentini Silvio 
Published: November 2010

AbstractIn this paper we analyze an extension of Martin‐Löf s intensional set theory by means of a set contructor P such that the elements of P(S) are the subsets of the set S. Since it seems natural to require some kind of extensionality on the equality among subsets, it turns out that such an extension cannot be constructive. In fact we will prove that this extension is classic, that is “(A V ⌝ A) true holds for any proposition A.
About Segment Complexity of Turing Reductions
Authors: Bulitko Valeriy K. 
Published: November 2010

AbstractWe apply complexity concepts to define a new sort of sub‐Turing reducibilities ≤ 𝔷 make the degree hierarchy thinner and to obtain some new specifications of the well known jump inversion theorem of Friedberg. We show that this theorem doesn't hold when ≤ T is replaced with ≤ 𝔷, where 𝔷 is any countable subset of the class 𝔷 of all total increasing functions f : ℕ → ℕ.
1H and 13C assignments of two new macrocyclic lactones isolated from Streptomyces sp. 211726 and revised assignments of Azalomycins F3a, F4aand F5a
Authors: Yuan Ganjun , Lin Haipeng , Wang Cheng , Hong Kui , Liu Yue , Li Jia 
Published: November 2010

AbstractAzalomycin F4a 2‐ethylpentyl ester (1) and Azalomycin F5a 2‐ethylpentyl ester (2), two new macrocyclic lactones, along with three known compounds of Azalomycins F3a (3), F4a (4) and F5a (5), were identified from metabolites of Streptomyces sp. 211726 isolated from mangrove rhizosphere soil. The complete 1H and 13C assignments of these compounds were achieved by using 1H, 13C, DEPT, HSQC, 1H‐1H COSY and HMBC spectra, and the relative stereochemistry of 5 was first elucidated on the basis of proton–proton coupling constants, NOESY and IR spectra. Moreover, some errors in the 1H and 13C assignments published of 3, 4 and 5 were found and revised. 1 and 2 were active against Candida albicans, and exhibited moderate cyctotoxicity against HCT‐116 cell line. Copyright © 2010 John Wiley & Sons, Ltd.
Electrical and rheological percolation in poly(vinylidene fluoride)/multi‐walled carbon nanotube nanocomposites
Authors: Martins Johnny N , Bassani Taís S , Barra Guilherme MO , Oliveira Ricardo VB 
Published: November 2010

AbstractNanocomposites of poly(vinylidene fluoride) (PVDF) and multi‐walled carbon nanotubes (MWCNTs) were prepared through melt blending in a batch mixer (torque rheometer equipped with a mixing chamber). The morphology, rheological behavior and electrical conductivity were investigated through transmission electron microscopy, dynamic oscillatory rheometry and the two‐probe method. The nanocomposite with 0.5 wt% MWCNT content presented a uniform dispersion through the PVDF matrix, whereas that with 1 wt% started to present a percolated network. For the nanocomposites with 2 and 5 wt% MWCNTs the formation of this nanotube network was clearly evident. The electrical percolation threshold at room temperature found for this system was about 1.2 wt% MWCNTs. The rheological percolation threshold fitted from viscosity was about 1 wt%, while the threshold fitted from storage modulus was 0.9 wt%. Thus fewer nanotubes are needed to approach the rheological percolation threshold than the electrical percolation threshold. Copyright © 2010 Society of Chemical Industry
Synthesis of quaternized ammonium iodide‐containing conjugated polymer electrolytes and their application in dye‐sensitized solar cells
Authors: Lee Rong‐Ho , Liu Jene‐Ku , Ho Jhu‐Heng , Chang Jhih‐Wei , Liu Bo‐Tau , Wang Hsing‐Ju , Jeng Ru‐Jong 
Published: November 2010

AbstractA series of conjugated polymer electrolytes (CPEs) comprising fluorene/carbazole or thiophene/carbazole backbones with quaternized ammonium iodide groups were synthesized and used in polymer solution and polymer gel electrolytes in dye‐sensitized solar cells (DSSCs). The photovoltaic (PV) performances became markedly poorer with increasing CPE content for the DSSCs based on polymer solution electrolytes. However, the PV performances were not significantly affected with increasing CPE content for the DSSCs fabricated from poly(ethylene oxide) (PEO)/CPE blend‐based gel‐type electrolytes. Moreover, higher PV efficiencies and stabilities were obtained for the DSSCs based on PEO/CPE blend gel electrolytes as compared to the DSSCs based on PEO gel electrolyte. The electrochemical impedance and PV properties of the DSSCs based on polymer solution electrolytes and on polymer gel electrolytes were determined as a function of the CPE concentration. Copyright © 2010 Society of Chemical Industry
Screening for symptoms of depression and anxiety in adolescents and young adults with cystic fibrosis
Authors: Modi Avani C. , Driscoll Kimberly A. , Montag‐Leifling Karen , Acton James D. 
Published: November 2010

AbstractBackgroundAlthough studies have assessed symptoms of depression and anxiety in individuals with cystic fibrosis (CF), few have been conducted since the advent of new medical treatments (e.g., nebulized antibiotics, ThAIRpy Vest). Study objectives were to: (1) document symptoms of depression and anxiety for adolescents and young adults with CF and compare with normative values, (2) examine the associations among depressive/anxiety symptoms and gender, age, lung function, and body mass index, and (3) determine the relations between adolescent and caregiver symptoms of depression and anxiety.MethodsPatients and caregivers completed the Hospital Anxiety and Depression Scale (HADS) anytime (e.g., beginning or end) during routine CF clinic appointments.ResultsParticipants included 59 adolescents/young adults with CF (Mage = 15.8 years, 54% female, 98% Caucasian, MFEV1% predicted = 84.6) and caregivers of 40 adolescents. Although symptom scores were in the normative range for patients with CF (MDepression = 2.27 and MAnxiety = 5.59), 3% and 32% exhibited clinically elevated symptoms of depression and anxiety, respectively. Symptoms of depression and anxiety were significantly associated with age (r = 0.28, 0.36). Symptoms of depression and anxiety were also positively correlated (r = 0.48). Females endorsed higher anxiety symptoms than males. While adolescent and caregiver anxiety scores were not related, higher caregiver depressive symptoms were associated with older patient age and worse lung function.ConclusionsData from the current study suggest low levels of depressive symptoms and substantial levels of anxiety symptoms in adolescents and young adults with CF. Consistent with prior literature, depressive symptoms appear higher in older patients and are significantly associated with anxiety symptoms. Caregiver symptomology appears to be more affected by an adolescent's health status, suggesting a need to screen caregivers when health begins to decline. Pediatr. Pulmonol. 2011; 46:153–159. © 2011 Wiley‐Liss, Inc.
Evaluation of interrupter resistance in methacholine challenge testing in children
Authors: Koopman Marije , Brackel Hein J.L. , Vaessen‐Verberne Anja A.P.H. , Hop Wim C. , van der Ent Cornelis K. ,   on behalf of the COMBO‐R Research Group
Published: November 2010

AbstractBronchial hyperresponsiveness (BHR) is a key feature of asthma and is assessed using bronchial provocation tests. The primary outcome in such tests (a 20% decrease in forced expiratory volume in 1 sec (FEV1)) is difficult to measure in young patients. This study evaluated the sensitivity and specificity of the interrupter resistance (Rint) technique, which does not require active patient participation, by comparing it to the primary outcome measure.Methacholine challenge tests were performed in children with a history of moderate asthma and BHR. Mean and individual changes in Rint and FEV1 were studied. A receiver operating characteristic (ROC) curve was used to describe sensitivity and specificity of Rint.Seventy‐three children (median age: 9.2 years; range: 6.3–13.4 years) participated. There was a significant (P < 0.01) increase in mean Rint with increasing methacholine doses. However, individual changes of Rint showed large fluctuations. There was great overlap in change of Rint between children who did and did not reach the FEV1 endpoint. A ROC curve showed an area under the curve of 0.65.Because of low sensitivity and specificity, the use of Rint to diagnose BHR in individual patients seems limited. Pediatr Pulmonol. 2011; 46:266–271. © 2011 Wiley‐Liss, Inc.
Prescribing hormone replacement therapy: the role of occupational stress
Authors: Chen Ruey‐Jien , Lu Luo 
Published: November 2010

AbstractThis study investigates whether physicians' levels of occupational stress may influence the likelihood of their prescribing hormone replacement therapy (HRT). One hundred and one physicians answered a cross‐sectional, mailed, self‐administered survey that measured occupational stress using Occupational Stress Indicator 2. Questions concerning HRT—including the possibility of recommending HRT to treat menopausal syndrome—were also asked. We found the likelihood of prescribing HRT for menopausal syndrome positively correlates with ‘coping’ (p < 0.01) and ‘other indications’ (p < 0.001). The likelihood of prescribing is also greater when the patient is a younger menopausal woman (p < 0.0001) and if the physician is more experienced (p < 0.05). Multiple regression analysis reveals that the ‘coping’ scale (p < 0.05) is the most significant factor, whereas ‘seeking support’ is the significant subscale (p < 0.0001). Our results indicate that ‘seeking support’ from the ‘coping’ scale is the most important factor that influences the prescribing of HRT. Copyright © 2010 John Wiley & Sons, Ltd.
Stretching the limits of visual attention: the case of action video games
Authors: Hubert‐Wallander Bjorn , Green C. Shawn , Bavelier Daphne 
Published: November 2010

AbstractVisual attention is the set of mechanisms by which relevant visual information is selected while irrelevant information is suppressed, thus allowing the observer to function in a world made up of nearly infinite visual information. Recently, those who habitually play video games have been documented to outperform novices in a variety of visual attentional capabilities, including attention in space, in time, and to objects. Training studies have established similar improvements in groups of nongamers given experience playing these video games. Critically, not all video games seem to have such a beneficial effect on attention; it seems that fast‐paced, embodied visuo‐motor tasks that require divided attention (tasks commonly found in popular action games like Halo) have the greatest effect. At the core of these action video game‐induced improvements appears to be a remarkable enhancement in the ability to efficiently deploy endogenous attention. The implications of such an enhancement are relevant to a variety of real‐world applications, such as work force training, rehabilitation of clinical populations, and improvement of traditional educational approaches. WIREs Cogni Sci 2011 2 222–230 DOI: 10.1002/wcs.116This article is categorized under:

Psychology > Learning
Quantitative analysis of yeast internal architecture using soft X‐ray tomography
Authors: Uchida Maho , Sun Yidi , McDermott Gerry , Knoechel Christian , Le Gros Mark A. , Parkinson Dilworth , Drubin David G. , Larabell Carolyn A. 
Published: November 2010

AbstractWe used soft X‐ray tomography (SXT)—a high‐resolution, quantitative imaging technique—to measure cell size and organelle volumes in yeasts. Cell size is a key factor in initiating cell division in yeasts, whereas the number and volume of the organelles have a profound impact on the function and viability of a cell. Consequently, determining these cell parameters is fundamentally important in understanding yeast biology. SXT is well suited to this type of analysis. Specimens are imaged in a near‐native state, and relatively large numbers of cells can be readily analysed. In this study, we characterized haploid and diploid strains of Saccharomyces cerevisiae at each of the key stages in the cell cycle and determined the relationships that exist cellular and organelle volumes. We then compared these results with SXT data obtained from Schizosaccharomyces pombe, the three main phenotypes displayed by the opportunistic yeast pathogen Candida albicans and from a coff1‐22 mutant strain of S. cerevisiae. This comparison revealed that volumetric ratios were invariant, irrespective of yeast strain, ploidy or morphology, leading to the conclusion these volumetric ratios are common in all yeasts. Copyright © 2010 John Wiley & Sons, Ltd.
Über die Fehlerabschätzung des Adams schen Verfahrens zur Integration gewöhnlicher Differentialgleichungen 1. Ordnung
Authors: Fricke Arnold 
Published: November 2010

AbstractDie von Tollmien für den Annäherungsgrad n=3 gegebene Fehlerabschätzung für die extrapolative und interpolative Form des Adamsschen Verfahrens zur numerischen Integration gewöhnlicher Differentialgleichungen 1. Ordnung wird auf einen beliebigen Annäherungsgrad verallgemeinert und verschärft. Die erhaltenen Fehlerschranken werden mit den von v. Mises und G. Schulz angegebenen verglichen und an Beispielen erläutert.
Zur hydrodynamischen Schmiertheorie des Zapfenlagers
Authors: Weber C. 
Published: November 2010

Abstract“Strebt nach der besten Lösung”Ausgehend von der Grundgleichung und vom Variationsproblem des endlichen Zapfenlagers wird die optimale Näherung der Druckfunktion gefunden für den Fall, daß die Näherung als Produkt einer Funktion von x (in Laufrichtung) und einer Funktion von z (in Achsrichtung des Zapfens) gewählt wird. Für die Funktion von z finden wir eine geschlossene Lösung, für die Funktion von x eine Differentialgleichung. Für diese wird an Hand eines Beispiels eine Lösungsmethode dargelegt. Für das Beispiel wird die Lagerkraft und ihre Richtung berechnet.
Zur elastisch‐plastischen Deformation des rotierenden Kreisrings
Authors: Gamer U. 
Published: November 2010

AbstractUntersucht wird der ebene Spannungszustand sowie die Deformation eines rotierenden Kreisrings aus elastisch‐plastischem Material mit linearer Verfestigung unter Zugrundelegung der Tresca schen Fließbedingung und der zugehörigen Fließregel.
Mathematische Deutung des ‘Flat Facet Models’ zur Bildverarbeitung
Authors: Werner H. 
Published: November 2010

AbstractIn dieser Note wird ein Verfahren für die Verarbeitung von gerasterten Bilddaten mit Hilfe des unten genauer definierten Facettenmodells zur Verschärfung der Konturen mathematisch gedeutet. Dazu nehmen wir an, daß die Grauwertverteilung über einem äguidistanten Raster T aus einer über dem gesamten Definitionsintervall gegebenen, etwa zweimal stetig differenzierbaren Funktion x gewonnen worden ist. Bei Anwendung des Bildverbesserungsprozesses entwickeln sich Sprungstellen jeweils zwischen zwei Rasterpunkten, die nahe bei Wendepunkten liegen, in denen der Betrag der ersten Ableitung, also |x|, ein relatives Maximum besitzt. Die Werte der Verteilungsfunktion streben bei der Iteration gegen eine auf jeder Facette (d. h. den Rasterpunkten zwischen den Sprungstellen) konstante Funktion X, deren Wert auf der Facette gegeben wird durch x(t) mit einem t, in dem |x| näherungsweise sein Minimum auf dieser Facette annimmt.
Heat and Mass Transfer in the Vapour Gas Region of a Gas‐Loaded Heat Pipe
Authors: Shukla K. N. , Sankara Rao K. 
Published: November 2010

AbstractA numerical analysis is made of the unsteady two‐dimensional heat and mass transfer in the vapour gas region of a gas‐loaded heat pipe. The parabolic mass, momentum, energy and species conservation equations for a symmetrical heat pipe are solved and the quantitative behaviour of the start up transient in the vapour gas region is presented.