bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application of oncogenetic trees mixtures as a biostatistical model of the clonal cytogenetic evolution of meningiomas
Authors: Ketter Ralf , Urbschat Steffi , Henn Wolfram , Feiden Wolfgang , Beerenwinkel Niko , Lengauer Thomas , Steudel Wolf‐Ingo , Zang Klaus D. , Rahnenführer Jörg 
Published: June 2007

AbstractMeningiomas are mostly benign tumors that originate from the coverings of brain and spinal cord. Typically, they reveal a normal karyotype or monosomy for chromosome 22. Rare clinical progression of meningiomas is associated with a nonrandom pattern of secondary losses of other autosomes. Deletion of the short arm of one chromosome 1 appears to be a decisive step for anaplastic growth in meningiomas. We calculated an oncogenetic tree model that estimates the most likely cytogenetic pathways of 661 meningioma patients in terms of accumulation of somatic chromosome changes in tumor cells. The genetic progression score (GPS) estimates the genetic status of a tumor as progression in the corresponding tumor cells along this model. Large GPS values are highly correlated with early recurrence of meningiomas [p< 10−4]. This correlation holds even if patients are stratified by WHO grade. We show that tumor location also has an impact on genetic progression. Clinical relevance of the GPS is thus demonstrated with respect to origin, WHO grade and recurrence of the tumor. As a quantitative measure the GPS allows a more precise assessment of the prognosis of meningiomas than categorical cytogenetic markers based on single chromosomal aberrations. © 2007 Wiley‐Liss, Inc.
Incidence rates of hepatocellular carcinoma in the U.S. and Denmark: Recent trends
Authors: Jepsen Peter , Vilstrup Hendrik , Tarone Robert E. , Friis Søren , Sørensen Henrik Toft 
Published: June 2007

AbstractHepatocellular carcinoma (HCC) incidence rates vary by gender, age, time and place. Geographic differences in gender‐, age‐ and time‐specific HCC incidence rates may improve the understanding of HCC risk factors. We computed annual standardized HCC incidence rates for the United States (U.S.) 1978–2004 and for Denmark 1978–2003. Among U.S. white men aged 45–59 the HCC incidence rates were comparable to the Danish rates until 1995, but more than tripled over the following 8 years to become over 2.5‐fold higher than the Danish rate by 2003, with an additional small increase in 2004. HCC rates in black U.S. men aged 45–59 also increased sharply after 1995. Among women aged 45–59 the U.S. HCC rates were elevated in recent years, but did not show the sharp increase after 1995 observed among men; the Danish rates showed a decreasing trend throughout 1978–2003. U.S. rates in the 60–74 years age groups showed a protracted and gradual increase with no evidence of a sharp increase after 1995. In the 60–74 years age group, rates for Danish men were comparable to those for U.S. white men, but rates for Danish women decreased. The U.S. prevalence rates of hepatitis C virus (HCV) infection are 2.1 and 1.1% for men and women, respectively, the Danish 0.2%. The disparity in HCV prevalence is the most likely explanation for the differences between Danish and U.S. trends in HCC incidence. Intravenous drug use and blood transfusions are the major sources of HCV, and we suggest that increased HCV infection prevalence among Vietnam era military veterans may contribute to the earlier and steeper HCC incidence increase for U.S. men than for U.S. women. © 2007 Wiley‐Liss, Inc.
Suppression of mesangial cell proliferation and extracellular matrix production in streptozotocin‐induced diabetic rats by Sp1 decoy oligodeoxynucleotide in vitro and in vivo
Authors: Kang Jeong Han , Chae Young‐Mi , Park Kwan‐Kyu , Kim Cheorl‐Ho , Lee In‐Seon , Chang Young‐Chae 
Published: June 2007

AbstractTranscription factor Sp‐1 is an important fibrogenic factor that is involved in the pathogenesis of diabetic nephropathy. In this study, we examined the effect of Sp1 decoy oligodeoxynucleotides (ODNs) on the extracellular matrix (ECM) gene expression in cultured rat mesangial cells (RMC) and streptozotocin (STZ)‐induced diabetic rats. The ring‐type Sp1 decoy ODNs significantly decreased ECM mRNA expression and Sp1 binding to the promoter region of these PDGF‐induced genes in RMC. In addition, the decoy ODNs was introduced into the left renal artery of diabetic rat using the hemagglutinating virus of Japan (HVJ)‐liposome mediated gene transfer method and effectively delivered to the kidney. On 14 days after ring‐type Sp1 decoy ODNs injection, type IV collagen, fibronectin mRNA, and protein expression were markedly decreased, and the rate of urinary creatinine excretion was reduced in the ring‐type Sp1 decoy ODNs‐treated diabetic rats. These results indicated that the ring‐type Sp1 decoy ODNs would be superior to P‐Sp1 ODNs. Also, the R‐Sp1 decoy ODN when introduced in vivo, effectively reduced ECM production during the progression of nephropathy. Therefore, ring‐type Sp1 decoy is a promising tool for developing new therapeutic applications for progressive diabetic nephropathy. J. Cell. Biochem. 103: 663–674, 2008. © 2007 Wiley‐Liss, Inc.
PyFrag—Streamlining your reaction path analysis
Authors: Zeist Willem‐Jan Van , Guerra Célia Fonseca , Bickelhaupt F. Matthias 
Published: June 2007

AbstractThe PyFrag program (released as PyFrag2007.01) is a “wrap‐around” for the Amsterdam Density Functional (ADF) package and facilitates the extension of the fragment analysis method implemented in ADF along an entire potential energy surface. The purpose is to make analyses of reaction paths and other (in principle also multidimensional) potential energy surfaces more transparent and user‐friendly. PyFrag also automates the analysis of reaction paths in terms of the extended activation strain model of chemical reactivity. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2008
A new detection algorithm for image analysis of single, fluorescence‐labeled proteins in living cells
Authors: Michel René , Steinmeyer Ralf , Falk Michael , Harms Gregory S. 
Published: June 2007

AbstractA new algorithm is presented for the detection of single, fluorescence‐labeled proteins in the analysis of images from living cells. It is especially suited for images with just a few (<1 per 10 μm2) fluorescence peaks from individual proteins with high background and noise (signal to background ratios as low as 2 and signal to noise as low as 10). The analysis uses the peaks over threshold method from extreme value theory and requires minimal assumptions on the underlying distributions. The significant advantage of the method over others is the rare occurrence to detect false positives. Some examples of simulated and real data are given as comparisons. The algorithm is implemented in MATLAB. Microsc. Res. Tech., 2007. © 2007 Wiley‐Liss, Inc.
Maximum diameter of regular digraphs
Authors: Soares Josè 
Published: June 2007

AbstractWe prove that everyr‐biregular digraph withnvertices has its directed diamter bounded by (3n‐r‐ 3)/(r+1). We show that this bound is tight for directed as well as for undirected graphs. The upper bound remains valid for Eulerian digraphs with minimum outdegreer. © 1929 John Wiley & Sons, Inc.
Directed star decompositions of the complete directed graph
Authors: Colbourn Charles J. , Hoffman D. G. , Rodger C. A. 
Published: June 2007

AbstractAn (s, t)‐directed star is a directed graph with s + t + 1 vertices and s + t arcs; s vertices have indegree zero and outdegree one, t have indegree one and outdegree zero, and one has indegree s and outdegree t. An (s, t)‐directed star decomposition is a partition of the arcs of a complete directed graph of order n into (s, t)‐directed starsx. We establish necessary and sufficient conditions on s, t, and n for an (s, t)‐directed star decomposition of order n to exist.
Laplacian and vibrational spectra for homogeneous graphs
Authors: Chung Fan R. K. , Sternberg Shlomo 
Published: June 2007

AbstractA homogeneous graph is a graph togerther with a group that acts transitively on vertices as symmertries of the graph. We consider Laplacians of homogeneous graphs and generalizations of Laplacians whose eigenvalues can be associated with various equilibria of forces in molecules (such as vibrational modes of buckyballs). Methods are given for calculating such eigenvalues by combining concepts and techniques in group representation theory, gauge theory and graph theory.
Total chromatic number of complete r‐partite graphs
Authors: Chew K. H. , Yap H. P. 
Published: June 2007

AbstractRosenfeld (1971) proved that the Total Colouring Conjecture holds for balanced complete r‐partite graphs. Bermond (1974) determined the exact total chromatic number of every balanced complete r‐partite graph. Rosenfeld's result had been generalized recently to complete r‐partite graphs by Yap (1989). The main result of this paper is to prove that the total chromatic number of every complete r‐partite graph G of odd order is Δ (G) + 1. This result gives a partial generalization of Bermond's theorem.
On the stability number of AH‐free graphs
Authors: Hertz A. , de Werra D. 
Published: June 2007

AbstractWe describe a new class of graphs for which the stability number can be obtained in polynomial time. The algorithm is based on an iterative procedure that, at each step, builds from a graph G a new graph Gl that has fewer nodes and has the property that α(Gl) = α(G) − 1.This new class of graphs is different from the known classes for which the stability number can be computed in polynomial time. © 1993 John Wiley & Sons, Inc.
A note on graphs and sphere orders
Authors: Scheinerman Edward R. 
Published: June 2007

AbstractA partially ordered set P is called a k‐sphere order if one can assign to each element a ∈ P a ball Ba in Rk so that a < b iff Ba ⊂ Bb. To a graph G = (V,E) associate a poset P(G) whose elements are the vertices and edges of G. We have v < e in P(G) exactly when v ∈ V, e ∈ E, and v is an end point of e. We show that P(G) is a 3‐sphere order for any graph G. It follows from E. R. Scheinerman [“A Note on Planar Graphs and Circle Orders,” SIAM Journal of Discrete Mathematics, Vol. 4 (1991), pp. 448–451] that the least k for which G embeds in Rk equals the least k for which P(G) is a k‐sphere order. For a simplicial complex K one can define P(K) by analogy to P(G) (namely, the face containment order). We prove that for each 2‐dimensional simplicial complex K, there exists a k so that P(K) is a k‐sphere order. © 1993 John Wiley & Sons, Inc.
A characterization of the smallest eigenvalue of a graph
Authors: Desai Madhav , Rao Vasant 
Published: June 2007

AbstractIt is well known that the smallest eigenvalue of the adjacency matrix of a connected d‐regular graph is at least − d and is strictly greater than − d if the graph is not bipartite. More generally, for any connected graph G = (V, E), consider the matrix Q = D + A where D is the diagonal matrix of degrees in the graph G and A is the adjacency matrix of G. Then Q is positive semidefinite, and the smallest eigenvalue of Q is 0 if and only if G is bipartite. We will study the separation of this eigenvalue from 0 in terms of the following measure of nonbipartiteness of G. For any S ⊆ V, we denote by emin(S) the minimum number of edges that need to be removed from the induced subgraph on S to make it bipartite. Also, we denote by cut(S) the set of edges with one end in S and the other in V − S. We define the parameter Ψ as.magnified imageThe parameter Ψ is a measure of the nonbipartiteness of the graph G. We will show that the smallest eigenvalue of Q is bounded above and below by functions of Ψ. For d‐regular graphs, this characterizes the separation of the smallest eigenvalue of the adjacency matrix from −d. These results can be easily extended to weighted graphs.
Bounds for the harmonious chromatic number of a graph
Authors: Krasikov I. , Roditty Y. 
Published: June 2007

AbstractThe upper bound for the harmonious chromatic number of a graph given by Zhikang Lu and by C. McDiarmid and Luo Xinhua, independently (Journal of Graph Theory, 1991, pp. 345–347 and 629–636) and the lower bound given by D. G. Beane, N. L. Biggs, and B. J. Wilson (Journal of Graph Theory, 1989, pp. 291–298) are improved.
Quasi‐median graphs and algebras
Authors: Bandelt Hans‐Jürgen , Mulder Henry Martyn , Wilkeit Elke 
Published: June 2007

AbstractScattered through the literature various structures occur that generalize median graphs and median algebras: quasi‐median graphs, retracts of Hamming graphs, graphs of finite windex, isotropic media, subdirect products of simplex algebras, certain ternary algebras, and so on. We connect them all up, provide some new generalizations of quasi‐median graphs, some new sets of axioms for quasi‐median algebras, and some shorter proofs as well.
The ramsey number r(k1 + c4, k5 − e)
Authors: Yuansheng Yang , Hendry G. R. T. 
Published: June 2007

AbstractThe graph K5 ‐ e is obtained from the complete graph K5 by deleting one edge, while K1 + C4 is obtained from K5 by deleting two independent edges. With the help of a computer it is shown that r(K1 + C4, K5 ‐ e) = 17. © 1995 John Wiley & Sons, Inc.
Squares, clique graphs, and chordality
Authors: Wallis W. D. , Wu Julin 
Published: June 2007

AbstractWe study the squares and the clique graphs of chordal graphs and various special classes of chordal graphs. Chordality conditions for squares and clique graphs are given. Several theorems concering chordal graphs are generalized. © 1996 John Wiley & Sons, Inc.
Insertible vertices, neighborhood intersections, and hamiltonicity
Authors: Ainouche A. , Schiermeyer I. 
Published: June 2007

AbstractLet G be a simple undirected graph of order n. For an independent set S ⊂ V(G) of k vertices, we define the k neighborhood intersections Si = {v ϵ V(G)&&num;92;S|N(v) ∩ S| = i}, 1 ≦ i ≦ k, with si = |Si|. Using the concept of insertible vertices and the concept of neighborhood intersections, we prove the following theorem.
Pseudo‐Interval Graphs
Authors: Brauner Erik O. , Brauldi Richard A. , Sneyd Elizabeth S. N. 
Published: June 2007

AbstractWe study a class of perfect graphs which, because they generalize interval graphs, we call pseudo‐interval graphs. Like interval graphs, their vertices correspond to intervals of a linearly ordered set, but a modified definition of intersection is used in order to determine edges. The complements of pseudo‐interval graphs are comparability graphs but unlike interval graphs, pseudo‐interval graphs are only weakly triangulated. We characterize trees and complements of trees which are pseudo‐interval graphs. Finally we determine all minimal non‐pseudointerval graphs on eight or fewer vertices whose complements are comparability graphs and which are weakly triangulated. © 1995 John Wiley & Sons; Inc.
Biclosure and bistability in a balanced bipartite graph
Authors: Amar Denise , Favaron Odile , Mago Pedro , Ordaz Oscar 
Published: June 2007

AbstractThe k‐biclosure of a balanced bipartite graph wiht color classes A and B is the graph obtained from G by recursively joining pairs of nonadjacent vertices respectively taken in A and B whose degree sum is at least k, until no such pair remains. A property P defined on all the balanced bipartite graphs of order 2n is k‐bistable if whenever G + ab has property P and dG(b) ≧ k then G itself has property P.We present a synthesis of results involving, for some properties, P, the bistability of P, the k‐biclosure of G, the number of edges and the minimum degree. © 1995 John Wiley & Sons, Inc.
Measurement of brain microglial proliferation rates in vivo in response to neuroinflammatory stimuli: Application to drug discovery
Authors: Shankaran Mahalakshmi , Marino Michael E. , Busch Robert , Keim Carole , King Chelsea , Lee Jean , Killion Salena , Awada Mohamad , Hellerstein Marc K. 
Published: June 2007

AbstractMicroglial activation is emerging as an important etiologic factor and therapeutic target in neurodegenerative and neuroinflammatory diseases. Techniques have been lacking, however, for measuring the different components of microglial activation independently in vivo. We describe a method for measuring microglial proliferation rates in vivo using heavy water (2H2O) labeling, and its application in screening for drugs that suppress neuro‐inflammation. Brain microglia were isolated by flow cytometry as F4/80+, CD11b+, CD45low cells, and 2H enrichment in DNA was analyzed by gas chromatography/mass spectrometry. Basal proliferation rate was ∼1%/week and systemic administration of bacterial lipopolysaccharide (LPS) markedly increased this rate in a dose‐dependent manner. Induction of experimental autoimmune encephalomyelitis (EAE) in C57BL/6 mice by MOG35–55 peptide stimulated proliferation of CD45low microglia, which could be distinguished from the proliferation of CD45high infiltrating monocytes. Minocycline (45 mg/kg/day, i.p.) inhibited resident microglial proliferation in both the LPS and EAE models. Thirteen drugs were then screened for their ability to inhibit LPS‐stimulated microglia proliferation. Female C57BL/6 mice were given LPS (1 mg/kg), and concomitant drug treatment while receiving 2H2O label for 7 days. Among the drugs screened, treatment with isotretinoin dose‐dependently reduced LPS‐induced microglial proliferation, representing an action of retinoids unknown previously. Follow‐up studies in the EAE model confirmed that isotretinoin not only inhibited proliferation of microglia but also delayed the onset of clinical symptoms. In conclusion, 2H2O labeling represents a relatively high‐throughput, quantitative, and highly reproducible technique for measuring microglial proliferation, and is useful for screening and discovering novel anti‐neuroinflammatory drugs. © 2007 Wiley‐Liss, Inc.
Coherent anti‐stokes Raman scattering imaging of myelin degradation reveals a calcium‐dependent pathway in lyso‐PtdCho‐induced demyelination
Authors: Fu Yan , Wang Haifeng , Huff Terry B. , Shi Riyi , Cheng Ji‐Xin 
Published: June 2007

AbstractCoherent anti‐Stokes Raman scattering (CARS) microscopy, which allows vibrational imaging of myelin sheath in its natural state, was applied to characterize lysophosphatidylcholine (lyso‐PtdCho)‐induced myelin degradation in tissues and in vivo. After the injection of lyso‐PtdCho into ex vivo spinal tissues or in vivo mouse sciatic nerves, myelin swelling characterized by the decrease of CARS intensity and loss of excitation polarization dependence was extensively observed. The swelling corresponds to myelin vesiculation and splitting observed by electron microscopy. The demyelination dynamics were quantified by the increase of g ratio measured from the CARS images. Treating spinal tissues with Ca2+ionophore A23187 resulted in the same kind of myelin degradation as lyso‐PtdCho. Moreover, the demyelination lesion size was significantly reduced upon preincubation of the spinal tissue with Ca2+free Krebs' solution or a cytosolic phospholipase A2(cPLA2) inhibitor or a calpain inhibitor. In accordance with the imaging results, removal of Ca2+or addition of cPLA2inhibitor or calpain inhibitor in the Krebs' solution remarkably increased the mean compound action potential amplitude in lyso‐PtdCho treated spinal tissues. Our results suggest that lyso‐PtdCho induces myelin degradation via Ca2+influx into myelin and subsequent activation of cPLA2and calpain, which break down the myelin lipids and proteins. The current work also shows that CARS microscopy is a potentially powerful tool for the study of demyelination. © 2007 Wiley‐Liss, Inc.
Thermoplastic Soy Protein Nanocomposites Reinforced by Carbon Nanotubes
Authors: Zheng Hua , Ai Fujin , Wei Ming , Huang Jin , Chang Peter R. 
Published: June 2007

AbstractMWNTs of various sizes were compounded into SPI matrix by solution mixing and then compression‐molded into nanocomposite sheets, which were characterized by XRD, SEM, TEM, and tensile and water uptake testing. The resultant nanocomposites showed improved mechanical performance and higher water resistance depending on MWNT size and content. This work details a strategy to achieve improved performance, especially in terms of mechanical properties, using MWNTs of various sizes to regulate the entanglement and penetration between SPI and MWNTs.magnified image
Combining Steric and Electrostatic Stabilization Using Hydrophilic MacroRAFT Agents in an Ab Initio Emulsion Polymerization of Styrene
Authors: dos Santos Amilton Martins , Pohn Jordan , Lansalot Muriel , D'Agosto Franck 
Published: June 2007

AbstractHydrophilic (co)polymers carrying a thiocarbonyl thio end group such as poly(dimethylaminoethyl methacrylate), poly(ethylene oxide), and poly(ethylene oxide)‐block‐poly(dimethylaminoethyl methacrylate) have been evaluated as precursors of stabilizers in batch ab initio emulsion polymerization of styrene under acidic conditions to form electrosterically stabilized polystyrene latex particles. As a mixture of P(DMAEMA/H+Cl−)‐RAFT and PEO‐RAFT failed to give satisfactory results, PEO‐RAFT was used as a control agent for the RAFT polymerization of DMAEMA, and the resulting block copolymer was successfully used in ab initio styrene emulsion polymerization.magnified image
A landlord's encounter with the underworld
Authors: Reynolds James Bronson 
Published: June 2007

AbstractThe author, a leading social worker, was in 1898 on Governor Roosevelt's Tenement‐House Commission which drafted laws defining and extending the responsibilities of landlords in relation to prostitution in tenement houses. He was a member of the staff of the District Attorney of New York County and special counsel to the so‐colled “White Slave Grand Jury,” which returned 26 indictments followed by convictions of offenders against the laws penalizing commercialized vice. He has since been an active leader in the fight against the social evil.
Thermodynamic stability of polyacrylamide and poly(N,N‐dimethyl acrylamide)
Authors: Reber Arthur C. , Khanna Shiv N. , Ottenbrite Raphael 
Published: June 2007

AbstractBased on theoretical thermodynamic principles, the possibility of environmental degradation of polyacrylamide to its starting monomer was investigated. Theoretical electronic structure studies on the geometry and fragmentation energy of acrylamide and N,N‐dimethyl acrylamide tetramer models were carried out using a first principles gradient corrected density functional approach. Thermal degradation to form a radical would require the cleavage of carbon–carbon bonds in the polymer chain; the energy needed for this cleavage was found to depend on the structure of the repeat unit which ranged from low of 72.5 kcal for a rare head‐to‐head construct to 86.2 kcal for a normal head‐to‐tail polymer construct (therefore, for the cleavage of a normal head‐to‐tail repeat unit, temperatures of approximately 450°C would be required). The thermodynamics of the unzipping, disproportionation, and back‐biting reactions in the resulting radical fragments were also investigated; the back‐biting process was found to require the least energy and provided the most stable radical fragment with a low probability for disproportionation or releasing of monomer to occur. The effect of solvation on the hydrogen‐bonding network in the acrylamide tetramer was studied by adding explicit molecules of water to the tetramer models. The addition of water had a significant effect on the stability of the model polymer slightly stabilizing the head‐to‐head polymer, and slightly destabilizing the head to tail polymer. Copyright © 2007 John Wiley & Sons, Ltd.