bluuebunny/crossref_metadata_2025_split huggingface dataset:
The threshold weight of a graph
Authors: Wang Chi , Williams A. C. 
Published: June 2007

AbstractThe threshold weight of a graph G is introduced as a measure of the amount by which G differs from being a threshold graph. The threshold graphs are precisely the graphs whose threshold weights are 0. At the opposite extreme is the class of graphs for which the threshold weight is the maximum possible. Such graphs are defined as heavy graphs. Among the results are as following: A theorem that specifies the threshold weight of any triangle‐free graph; necessary and sufficient conditions for a heavy graph in terms of the solvability of a system of linear inequalities; some sufficient conditions for a graph to be heavy and a necessary condition (conjectured to be sufficient, as well) for a heavy graph in terms of its cliques.
Regular factors in K1,n free graphs
Authors: Egawa Yoshimi , Ota Katsuhiro 
Published: June 2007

AbstractA graph is said to be K1,n‐free, if it contains no K1,n as an induced subgraph. We prove that for n ⩾ 3 and r ⩾ n −1, if G is a K1,n‐free graph with minimum degree at least (n2/4(n −1))r + (3n −6)/2 + (n −1)/4r, then G has an r‐factor (in the case where r is even, the condition r ⩾ n −1 can be dropped).
Niche numbers
Authors: Fishburn P. C. , Gehrlein W. V. 
Published: June 2007

AbstractAn acyclic digraph D =(V U X, <) induces a finite graph G =(V, E) if for all v,v′ if and only if a vertex of D dominates v and v′, or is dominated by v and v′. The niche number of an induced G is the cardinality of a smallest X for which some D induces G. Many induced graphs have niche number 0, 1, or 2, but it has been an open problem as to whether they can have larger niche numbers. We prove that there are induced graphs with arbitrarily large niche numbers. Explicit examples of graphs with niche numbers 3 and 4 are given. The smallest example uses 11 vertices. We note also that every induced graph with fewer than 8 vertices has niche number 0, 1, or 2.
Supereulerian graphs: A survey
Authors: Catlin Paul A. 
Published: June 2007

AbstractA graph is supereulerian if it has a spanning eulerian subgraph. There is a rduction method to determine whether a graph is supereulerian, and it can also be applied to study other concepts, e.g., hamiltonian line graphs, a certain type of double cycle cover, and the total interval number of a graph. We outline the research on supereulerian graphs, the reduction method, and its applications.
An upper bound for the total chromatic number of dense graphs
Authors: Hind H. R. 
Published: June 2007

AbstractIn this paper we consider those graphs that have maximum degree at least 1/k times their order, where k is a (small) positive integer. A result of Hajnal and Szemerédi concerning equitable vertex‐colorings and an adaptation of the standard proof of Vizing's Theorem are used to show that if the maximum degree of a graph G satisfies Δ(G) ≥ |V(G)/k, then X″(G) ≤ Δ(G) + 2k + 1. This upper bound is an improvement on the currently available upper bounds for dense graphs having large order.
Almost all steinhaus graphs have diameter 2
Authors: Brand Neal 
Published: June 2007

AbstractA Steinhaus graph is a graph with n vertices whose adjacency matrix (ai, j) satisfies the condition that ai, j  aa‐‐1, j‐‐1 + a i‐‐1, j (mod 2) for each 1 < i < j ≤ n. It is clear that a Steinhaus graph is determined by its first row. In [3] Bringham and Dutton conjecture that almost all Steinhaus graphs have diameter 2. That is, as n approaches infinity, the ratio of the number of Steinhaus graphs with n vertices having diameter 2 to the total number of Steinhaus graphs approaches 1. Here we prove Bringham and Dutton's conjecture.
New results on rectilinear crossing numbers and plane embeddings
Authors: Bienstock Daniel , Dean Nathaniel 
Published: June 2007

AbstractWe show that if a graph has maximum degree d and crossing number k, its rectilinear crossing number is at most O(dk2). Hence for graphs of bounded degree, the crossing number and the rectilinear crossing number are bounded as functions of one another. We also obtain a generalization of Tutte's theorem on convex embeddings of 3‐connected plane graphs. © 1929 John Wiley & Sons, Inc.
Synthesis of deuterium‐labelled chlorhexidine
Authors: Moser M. , Hudlicky T. , Sadeghi S. , Sternin E. 
Published: June 2007

AbstractThe synthesis of deuterated chlorhexidine hydrochloride is reported. The specific labelling of the saturated chain is achieved through the combination of the previously reported synthesis of 2,2,3,3,4,4,5,5‐(2H8)‐hexane‐1,6‐diol and a synthesis of carbon‐14 labelled chlorhexidine. This synthesis begins with commercially available hex‐2,4‐yne‐1,6‐diol, its protection as a bis‐tetrahydropyranylether, and exhaustive deuterogenation under rhodium catalysis to produce, after acid hydrolysis of the protecting groups, the saturated octadeuterated 1,6‐hexanediol. Conversion of this material in two steps to the corresponding 1,6‐diaminohexane was followed by the generation of guanidines with dicyanimide and final condensation with p‐chloroaniline. The title compound was obtained in 10 chemical steps and in 6% overall yield. Copyright © 2007 John Wiley & Sons, Ltd.
An efficient large‐scale synthesis of 1H‐indazole‐[3‐14C]carboxylic acid
Authors: Coelho Richard V. , Schildknegt Klaas 
Published: June 2007

AbstractAn efficient large‐scale carbon‐14 synthesis of 1H‐indazole‐[3‐14C]carboxylic acid starting from [14C]potassium cyanide is reported. Key transformations encountered during the synthesis include aromatic nucleophilic substitution of 2‐nitrofluorobenzene by ethyl [14C]cyanoacetate, a mild decarbethoxylation and an aniline nitrosation/cyclization. Copyright © 2007 John Wiley & Sons, Ltd.
Validating the current amino acid and energy requirements of coloured broiler chickens
Authors: Bhanja Subrat K , Mandal Asit B 
Published: June 2007

AbstractBackground: Coloured broilers are gaining popularity in the Indian subcontinent. However, very scanty reports are available on their dietary requirements for amino acid (AA) and energy. An experiment was conducted involving three levels of amino acids (115, 100 and 85% AA level of the NRC), at three levels of energy (13.40, 12.55 and 11.72 MJ kg−1 diet) for 0–28 days of age. Results: Body weight gain and feed conversion ratio (FCR) in the 115% AA group was better than those fed diets with 100 and 85% AA. Dietary energy levels did not influence body weight gain up to 14 days of age but thereafter it was higher (P < 0.01) in birds offered the 13.40 MJ ME kg−1 diet. The exponential regression equation had better curve fitting for daily body weight gain over daily AA intake and the power regression model for FCR. Nitrogen retention was higher in birds offered the diets with 115 and 100% AA than 85% AA, although nitrogen retention was not affected by dietary energy level. Thymus weight (P < 0.036) and in vivo response to PHA‐P (P < 0.006) was significantly higher in birds offered the 85% AA diet. Dietary energy levels had no effect on the immune response of the birds. Weight of gizzard, proven‐triculus and small intestine was higher in birds offered the 85% AA diet. Conclusion: Body weight of coloured broilers may be optimised by feeding higher level of AA and immune response can be optimised by feeding 12.55 kJ ME kg−1 diet and 15% lower level of AA as suggested by the US National Research Council. Copyright © 2007 Society of Chemical Industry
The work of the reconstruction legislatures
Authors: Rex Frederick , Childs Richard S. , Helpful Many 
Published: June 2007

AbstractOne of our ambitions for the “Review” in its new monthly form is to make it more of a newspaper; hence this attempt to cover the legislative high points as early as possible. Since five legislatures are still in session as we go to press, the record is necessarily incomplete. Corrections will be welcomed and will be published later. See also the summary in the Editorials.
The fate of the five‐cent fare VI. The municipal street railway in san francisco
Authors: O'shaughnessy M. M. 
Published: June 2007

AbstractThe successful operation of sixty miles of street car lines by the city of San Francisco has long been a favorite citation of the advocates of municipal operation. The enterprize is beginning to borrow pay roll money from its depreciation fund and is evidently not immune from the prevailing malady of high costs.
City manager movement: Progress of manager plan in one hundred eighty‐five cities
Authors: Otis Harrison Gray 
Published: June 2007

AbstractThis series of short stories began in the May 1920 issue oj the REVIEW. Since the above title was selected, the number of American cities operating under, or pledged to, the city manager plan, has increased to well over the two hundred mark, and many elections have been called for early in 1921.
The fate of the five‐cent fare: XIII. Philadelphia succumbs
Authors: Stirling Edmund , Cooke Morris Llewellyn 
Published: June 2007

AbstractAn operating company, burdened by unconscionable rentals and fixed charges, surviving the war on the five‐cent fare; the fare raised last November over the protest of a manager faithful to the old rate; opposition between management and financial control—these are some of the reasons why the story of the Philadelphia Rapid Transit is extraordinary.
Omaha's experience with the commission plan
Authors: Rosewater Victor 
Published: June 2007

AbstractIt was predicted in short ballot pamphlets long ago that Omaha's non‐partisan ballot of seven ofices, instead of the usual five or three, would automatically lead the voters again to dependence upon slates made up by interested parties and give advantage to slate candidates over independents. This prediction has proven correct. Otherwise this story reports typical results of defects inherent in commission government.
Peptidomic analysis of rat urine using capillary electrophoresis coupled to mass spectrometry
Authors: Frommberger Moritz , Zürbig Petra , Jantos Justyna , Krahn Thomas , Mischak Harald , Pich Andreas , Just Ingo , Schmitt‐Kopplin Philippe , Schiffer Eric 
Published: June 2007

AbstractWe have established and validated a protocol for the peptidomic analysis of rat urine using CE coupled to MS (CE‐MS). In the first experiments, the reproducibility of the CE‐MS set‐up and of the established preparation procedure were assessed. To establish a first rat urinary peptidome map, samples were also analyzed using CE‐FT‐ICR. The subsequent analysis of independent samples from two different strains (WISTAR and CD) indicated strain‐specific differences, which were validated in a blinded assessment. MS/MS revealed the presence of specific fragments from well‐known urinary rat peptides, such as collagens, alpha‐1‐antitrypsin, and serum albumin. The CE‐MS‐based peptidomics platform may provide novel insights into body fluids of animal models, such as rat or mice. Together with peptide identification, the technology appears to be an excellent, complimentary, and non‐invasive tool to analyze toxicological or other (patho)physiological effects of pharmaceutical compounds in animal models.
Imaging of protein layers with an optical microscope for the characterization of peptide microarrays
Authors: Souplet Vianney , Desmet Rémi , Melnyk Oleg 
Published: June 2007

AbstractSolid‐phase assays play a crucial role today in biological studies. These assays are based on the immobilization of probe molecules on a surface, which are able to capture specifically soluble receptors. In particular, peptide microarrays have emerged as powerful tools in a variety of applications. In this context, optical techniques that allow imaging of nanometer‐thick biomolecular films, and thereby the characterization of microarrays, are of great interest. For this purpose, we used a recently disclosed wide‐field optical imaging technique of surface nanostructures called Sarfus, which is based on the use of a standard optical microscope and antireflection substrates. We demonstrate here that this technique allows the imaging of the protein layers that result from the specific capture of antibodies by arrayed peptide probes with a spatial resolution of 0.45 µm. The relationship between the thickness of the antibody layer and peptide or antibody concentration was examined. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd.
Total solid‐phase synthesis of bombesin analogs with different functional groups at the C‐terminus
Authors: Abd‐Elgaliel Wael R. , Gallazzi Fabio , Lever Susan Z. 
Published: June 2007

AbstractFive bombesin analogs with different functional groups at the C‐terminus were synthesized using a solid‐phase strategy. The protocols were optimized using 4‐(hydroxymethyl)benzoic acid (HMBA) resin to synthesize a common precursor followed by nucleophilic cleavage of the base sensitive peptide ester linkage. The C‐terminal modifications included ethylamide, butylamide, methyl ester, propyl ester and hydrazide. Cleavage from the resin was possible with the fully protected or deprotected precursor peptide; however, higher purity of the final products was achieved when cleavage protocols were conducted after side‐chain deprotection. The synthesized peptides were analyzed and characterized using reverse phase HPLC and ESI‐MS. The peptides were obtained in 13–32% overall recovery, calculated from the coupling efficiency of the first amino acid residue, and in 91–97% purity. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd.
Sonographic estimation of fetal weight: comparison of bias, precision and consistency using 12 different formulae
Authors: Anderson N. G. , Jolley I. J. , Wells J. E. 
Published: June 2007

AbstractObjectivesTo determine the major sources of error in ultrasonographic assessment of fetal weight and whether they have changed over the last decade.MethodsWe performed a prospective observational study in 1991 and again in 2000 of a mixed‐risk pregnancy population, estimating fetal weight within 7 days of delivery. In 1991, the Rose and McCallum formula was used for 72 deliveries. Inter‐ and intraobserver agreement was assessed within this group. Bland–Altman measures of agreement from log data were calculated as ratios. We repeated the study in 2000 in 208 consecutive deliveries, comparing predicted and actual weights for 12 published equations using Bland–Altman and percentage error methods. We compared bias (mean percentage error), precision (SD percentage error), and their consistency across the weight ranges.Results95% limits of agreement ranged from − 4.4% to + 3.3% for inter‐ and intraobserver estimates, but were − 18.0% to 24.0% for estimated and actual birth weight. There was no improvement in accuracy between 1991 and 2000. In 2000 only six of the 12 published formulae had overall bias within 7% and precision within 15%. There was greater bias and poorer precision in nearly all equations if the birth weight was < 1000 g.ConclusionsObserver error is a relatively minor component of the error in estimating fetal weight; error due to the equation is a larger source of error. Improvements in ultrasound technology have not improved the accuracy of estimating fetal weight. Comparison of methods of estimating fetal weight requires statistical methods that can separate out bias, precision and consistency. Estimating fetal weight in the very low birth weight infant is subject to much greater error than it is in larger babies. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
The Initial Value Problem for the General Dynamic Equations in Nonlinear Elasticity Theory
Authors: Beckert H. 
Published: June 2007

AbstractIn this paper the initial value problem for the general dynamic equations in an elastic continuum is solved. At first, we introduce a new form for these equations and define a simple approximation for the solutions of our problem along a difference scheme in the time direction calculating the changing stress configurations as in the authors theory for quasistatic deformations in nonlinear elasticity [1], [2]. The convergence of this approximation to the solution of the initial value problem above is proved. In the last chapter this theory is generalized to include damping material.
On a Maximum Principle for Matrices, and on Conservation of Monotonicity. With Applications to Discretization Methods
Authors: Stoyan G. 
Published: June 2007

AbstractConsidered are two kinds of monotonicity properties of systems of linear equations. Firstly, a maximum principle is defined for matrices of monotone kind, and sufficient conditions are given for its validity. Secondly, for more special systems, sufficient conditions are established under which (componentwise) monotonicity of the right‐hand side implies monotonicity of the solution. A series of examples is considered for the investigated concepts, mainly from the context of difference schemes, leading to some new results for well‐known schemes.
A Class of Runge‐Kutta‐Rosenbrock Methods for Solving Stiff Differential Equations
Authors: Verwer J. G. , Scholz S. , Blom J. G. , Louter‐Nool M. 
Published: June 2007

AbstractA class of Runge‐Kutta‐Rosenbrock methods is discussed for the numerical solution of the initial value problem for stiff systems of ordinary differential equations. We pay special attention to the use of time‐lagged Jacobian matrices. The aim is to obtain an appreciable reduction in the number of Jacobian matrix evaluations and related matrix factorizations. When dealing with large systems the costs of these computations normally form a large proportion of the total integration costs of the Rosenbrock method.
Über ein Drei‐Kammer‐Modell der Haemodialyse
Authors: Krabs W. 
Published: June 2007

AbstractIn dieser Arbeit wird ein mathematisches Modell für den Vorgang der Haemodialyse entwickelt, das auf einer Zerlegung des menschlichen Körpers in den Extrazellularbereich, den Zellularbereich und das Gehirn als getrennten Teil des letzteren beruht. Unter gewissen Periodizitätsannahmen für den Prozeß wird gezeigt, daß für beliebige Durchlässigkeiten der Zellmembranen sich eindeutige periodische Lösungen für die zeitliche Entwicklung der Giftstoffkonzentration in den drei Bereichen ergeben. Für einen realistischen Wert der allgemeinen Zelldurchlässigkeit und mehrere Werte für den zur Zeit noch unbekannten Wert der Durchlässigkeit der Gehirnzellen werden diese periodischen Lösungen auch berechnet und diskutiert.
Instationäre Zufallsschwingungen einer elastischen Gewichtsmauer bei beliebig geformtem Becken
Authors: Höllinger F. , Ziegler F. 
Published: June 2007

AbstractEs wird ein Berechnungsverfahren für erdbebenerregte Schwingungen einer linear elastischen Gewichtsmauer (im ebenen Verzerrungszustand) unter Berücksichtigung der Schwingungsinteraktion mit dem zweidimensionalen, linear kompressiblen, reibungsfreien Flüssigkeitskörper in einem beliebig geformten zylindrischen Staubecken vorgestellt. Die Behandlung des ebenen hydrodynamischen Problems erfolgt mittels einer Randintegralgleichungsmethode. Die ebenen Schwingungen zufolge instationärer Zufallserregung werden durch instationäre Spektraldichten beschrieben.
Partial Integrability as the Basis for the Existence of Entropy in Irreversible Systems
Authors: Valanis K. C. 
Published: June 2007

AbstractThe concept of internal forces of the first and second kind is introduced and discussed. The physical basis for thermodynamic inaccessibility is established. The existence of entropy for irreversible systems is then proved on the basis of the concept of ‚partial integrability’︁ of Pfaffian forms. Evolution equations for the internal variables are thereby proposed and discussed.
Solution of Large Sparse Nonlinear Systems by Monotone Convergent Iterations and Applications
Authors: El‐Seoud S. Abou , Törnig W. 
Published: June 2007

AbstractIn this paper we describe a family of Gauss‐Seidel‐iterations for the solution of large sparse nonlinear systems of equations Fx = 0. The mapping F is off‐diagonally antitone and strictly diagonally isotone. For suitable starting vectors every method of this family is monotonically convergent with respect to both sides. The iteration processes will be applied among others to the numerical solution of boundary value problems of quasilinear potential equations.
Zur Äquivalenz der Zeitintegrationsverfahren für dynamische Systeme
Authors: Weber M. 
Published: June 2007

AbstractDie wichtigsten Verfahren zur direkten Zeitintegration dynamischer Systeme werden nach der Art ihrer Herleitung in verschiedene Klassen eingeteilt. Für lineare gedämpfte Systeme wird gezeigt, daß man für einen bestimmten Ansatz aus unterschiedlichen Herleitungen Integrationsverfahren mit gleichen Eigenschaften (bzgl. numerischer Stabilität, Konvergenz und Abschneidefehler) erhält. Außerdem wird nachgewiesen, daß es für jeden Grad des Ansatzes (linear, kubisch, usw.) nur ein optimales Verfahren gibt, das unbedingt stabil arbeitet und keine verfahrenseigene Amplitudendämpfung besitzt. Dieses optimale Verfahren erhält man aus den verschiedenen Herleitungen in unterschiedlicher Form.
Small‐amplitude Finite‐rate Waves in Suspensions of Particles in Fluids
Authors: Kluwick A. 
Published: June 2007

AbstractThe paper deals with the propagation of weakly nonlinear waves in homogeneous suspensions. Under the assumption that a one‐dimensional treatment is adequate the properties of these waves are investigated in stable as well as unstable flow and near the stability limit. Special emphasis is placed on the discussion of waves of constant form.
The Theory of Scalar Plastic Deformation Functions
Authors: Rees D. W. A. 
Published: June 2007

AbstractStarting with the assumption of initial isotropy and the kinematic hardening rule the anisotropic nature of plastic deformation in polycrystalline materials is expressed through functions of two deformation scalars which in themselves are polynomial functions of the seven independent invariants of the deviatoric stress and plastic strain tensors. These former functions are shown to represent closely the translation, contraction, rotation and distortion that has been observed in experimental yield loci under combined tension and torsion. A physical interpretation is presented for the case of a linear workhardening material displaying a Bauschinger effect and an absence of cross‐hardening at the limit of proportionality.
A Boundary‐Layer Theory for the Orthotropic Plate
Authors: Gilbert R. P. , Schneider M. 
Published: June 2007

AbstractThe purpose of this paper is to show that the equations of three dimensional anisotropic elasticity can be split into two independent systems. Whereas it has been known since the pioneering work by K. O. Friedrichs and R. F. Dressler [5] that this was the case for isotropic materials it is by no means obvious that this is true in general. We consider in what follows only the case where the traction is specified on the lateral surface and the upper and lower surfaces; furthermore, the plate is to be in a state of equilibrium. We shall proceed to solve asymptotically the differential equations of the problem.