bluuebunny/crossref_metadata_2025 huggingface dataset:
Adjusting for Multiplicity of Statistical Tests in the Analysis of Carcinogenicity Studies
Authors: Heyse J. F. , Rom D.
Published: May 2007

Because the evaluation of rodent carcinogenicity studies involves performing a statistical analysis at each tumor site encountered it is important to understand the extent to which this multiplicity affects the false positive rate. It is equally important to apply methods of accounting for this multiplicity in the analysis.

In this paper we discuss one such method which involves calculating the overall significance level associated with P1, the most extreme isolated trend P‐value observed among the tumor sites encountered. The method constructs the distribution of trend scores simultaneously for each tumor site using a multiresponse randomization procedure. As such, it recognizes the discrete nature of the data and incorporates inherent dependencis that may exist between the tumor sites.

For small studies it is possible to perform a complete rerandomization and compute an exact adjusted trend P‐value. However, for moderate or large studies the need exists for approximations based on efficient resampling plans. We report one such approximation proposed by Dr. John Tukey which involves correcting the exact Bonferroni upper bound. Also, we show that the independence assumption used in methods proposed by Mantel (1980) and Mantel et al. (1982) seems to be a reasonable approximation for the study discussed in the present report. This result needs to be supported further using additional studies.
Binary Data in Prerandomized Designs
Authors: Bernhard G. , Compagnone D.
Published: May 2007

In 1979 and 1981 Zelen introduced the so‐called prerandomized designs as an alternative to the completely randomized trial of therapies: The participants of the trial are first (pre‐) randomized to the treatment groups and asked afterwards for their consent. In the case of binary data, tests for selection and treatment effects in the simple and double prerandomized design are derived and then illustrated by a numerical example.
Application of the Biased Spring Balance Weighing Design Theory to Estimation of Differences of Line Effects for Legume Content
Authors: Ceranka B. , Katulska K.
Published: May 2007

The incidence matrix of a BIB design for v treatments has been used to construct a biased spring balance weighing design. Conditions under which an optimum biased spring balance weighing design exists are given. It is also shown how this theory may be utilized to obtain treatment and experiment designs to estimate differences in legume content between pair of lines in an experiment overseeded with grass species.
Complex Segregation Analysis on Multi‐Modal Distributions
Authors: Tai J. J. , Gross A. J.
Published: May 2007

By using sib‐pairs and parent‐pairs data, Tai and Gross (1988) proposed a method to test the existence of a 2‐allele major locus for a quantitative trait. This method is extended to include three alleles at a major locus in this paper. One may perform this extension in a feasible and practical manner. To show the advantage of this extension, a simulated data set of nuclear families from a 3‐allele ordered dominant (i.e., A > B, A > W and B > W in our notation) major locus model for a quantitative trait is analyzed by a 2‐allele codominant major locus mixed model and a 3‐allele ordered dominant major locus mixed model. The result shows that our method can distinguish between ambiguous trimodal distributions.
A Note on Block Designs with Nested Rows and Columns
Authors: Singh Murari
Published: May 2007

Block designs with nested rows and columns have been introduced by Singh and Dey (1979). This note gives some results regarding the total relative loss of information and patterns of efficiency balanced block designs with nested rows and columns in variable replications of treatments.
Analysis of Phenetic Relationships Among Populations of the Avian Genus Batis (Platysteirinae) by Means of Cluster Analysis and Multidimensional Scaling
Authors: Lawson Walter J. , Ogg Patti J.
Published: May 2007

In the course of a study of the evolution of a genus of African flycatchers, Batis, numerical techniques were employed to analyse the characters of the populations of the forest‐dwelling Batis and to throw some light on their relationships. The techniques reported upon in this paper are non‐metric multidimensional scaling (MDS) and the Unweighted Pair‐group Method using Arithmetic Averages (UPGMA). The results obtained from these numeric analyses closely parallel those using non‐quantitative methods.
A Nonparametric Test for Differences in the Dispersion of Dependent Samples
Authors: Boehnke K.
Published: May 2007

A new statistic Δ to test the hypothesis of a difference in the dispersion of two dependent samples of ordinal data quality is proposed. It draws on the idea of rank assignment originally forwarded by Siegel and Tukey (1960). No exact probability levels can be given for this statistic for the time being, but it is shown that the statistic is linearly related to the so‐called Hotelling‐Pabst statistic D, and that one can use exact tables of the latter as a substitute in the statistical decision process with small samples. For larger samples, an approximation of Δ to the standard normal distribution is given. The problem of tied observations is not sufficiently solved yet. A conservative procedure of rank assignment is proposed as long as the exact distribution of Δ in the presence of ties is unknown.
Edge‐corrected Estimators for the Reduced Second Moment Measure of Point Processes
Authors: Doguwa Sani I. , Upton Graham J. G.
Published: May 2007

A new edge‐corrected estimator is proposed for the second moment cumulative functionK(t)introduced by Ripley (1977,Journal of the Royal Statistical Society, Series B39, 172–212). This new estimator is compared by simulation methods with existing edge‐corrected estimators in the context of bothK(t)andL(t)functions which are used to study point patterns. The results of the simulation study suggests that the new estimator provides almost unbiased estimates ofK(t)andL(t)and has a smaller mean squared error than its predecessors.
Binary Responses and the Three‐period Cross‐over
Authors: Morrey G. H.
Published: May 2007

Problems with carry‐over effects in the simple two‐period cross‐over have lead to interest in more complex cross‐over designs. A method for analysing the optimum two‐treatment three‐period design with binary response variables is given by making a simple extension to Gart's logistic model. The method gives independent tests for, and estimates of the difference in treatment and first‐order carry‐over effects. An example of the analysis is given, using the loglinear models facility in GLIM.
Asymptotic Efficiency of the Chi‐Square Test for Heterogeneity of Proportions in Some Sparse‐Data Cases
Authors: Anderson S. , Hauck W. W.
Published: May 2007

We consider the problem of testing for heterogeneity of K proportions when K is not small and the binomial sample sizes may not be large. We assume that the binomial proportions are normally distributed with variance σ2. The asymptotic relative efficiency (ARE) of the usual chi‐square test is found relative to the likelihood‐based tests for σ2=0. The chi‐square test is found to have ARE = 1 when the binomial sample sizes are all equal and high relative efficiency for other cases. The efficiency is low only in cases where there is insufficient data to use the chi‐square test.
On Allocation Problem in Stratified Sampling
Authors: Deshpande M. N. , Prabhu‐Ajgaonkab S. G.
Published: May 2007

In this paper we discuss some aspects of allocation problem in stratified sampling.
Two Models for Interaction in a 3‐way Analysis of Variance With One Observation Per Cell
Authors: Onukogu Ike B. , Ama N. O.
Published: May 2007

The paper shows that three factor interaction can be represented by two different models in a 3‐way classification without replications. Each model is developed as a product of the three main effects plus the sum of the products of a main effect and a two‐factor interaction. A conditional F‐test for non‐additivity is derived from each model.

A pseudo‐correlation exists between the models and as this correlation coefficient tends to unity the models are shown to converge. Extension of the procedure to four‐factor interaction and higher is indicated.
A Note on Sire Evaluation with Uncertain Paternity
Authors: Im S.
Published: May 2007

We consider sire evaluation for situations in which paternity is uncertain. We show how mixed models equations can be used to obtain the best linear unbiased predictors for sire evaluation in such situations.
Improvement of Ratio‐Type Estimators
Authors: Tankou Victoire , Dharmadhikari Sudhakar
Published: May 2007

This paper proposes a method for using multi‐auxiliary information at both the design and the estimation stages of a sample survey. The proposed method is an extension of the classical multivariate method of Olkin (1958). The results of Agarwal and Kumar (1978) come out as a special case.
Estimation of Variances at Different Significance Levels
Authors: de Ron A. M. , Ordas A.
Published: May 2007

Variance components and their ratios broad‐sense heritability and constancy were estimated for some quantitative traits in northwestern Spain populations of maize. Estimations were carried out at the significance levels of 5% and 25% and without significance limits. It can be concluded that estimation without significance limits is more efficient than the estimations at the usual levels in the method of analysis of experimental data from fields experiments.
Single‐walled tubulin ring polymers
Authors: Boukari Hacène , Sackett Dan L. , Schuck Peter , Nossal Ralph J.
Published: May 2007

An unusual class of nanoscopic, ring‐shaped, single‐walled biopolymers arises when αβ‐tubulin is mixed with certain small peptides obtained from various marine organisms and cyanobacteria. The single‐ring structures, whose mean molecular weight depends on the specific peptide added to the reaction mixture, usually have sharp mass distributions corresponding, e.g., to rings containing eight tubulin dimers (when the added peptide is cryptophycin) and 14 dimers (e.g., with dolastatin). Although the ring‐forming peptides have been shown to possess antimitotic properties when tested with cultured eukaryotic cells (and thus have generated considerable interest as possible agents to be used in the treatment of cancer), it is not our intention to extensively discuss the potential pharmacological properties of the peptides. Rather, we will review the polymeric structures that form and illustrate how certain physical techniques can be used to characterize their properties and interactions. The nanoscopic size and particular geometry of the individual rings make them appropriate targets for scattering and hydrodynamic techniques that provide details about their structure in solution, but it is necessary to relate measured data to postulated structures by nontrivial, albeit straight‐forward, mathematical, and computational means. We will discuss how this is done when one uses such methods as small angle neutron scattering, dynamic light scattering, fluorescence correlation spectroscopy, and sedimentation velocity measurements. Moreover, we show that, by using several techniques, one can eliminate degeneracy to provide better discrimination between model structures. © 2007 Wiley Periodicals, Inc. Biopolymers 86: 424–436, 2007.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Reactions of tBu2AlH and RE(SiMe3)2 (R = H, SiMe3) – Synthesis and X‐ray Crystal Structures of [tBu2AlP(H)SiMe3]2 and [tBu2AlE(SiMe3)2]2 (E = Sb, Bi)
Authors: Matar Madhat , Kuczkowski Andreas , Keßler Ulrich , Schulz Stephan , Flörke Ulrich
Published: May 2007

Dehydrosilylation reactions between tBu2AlH and E(SiMe3)3 yielded the four‐membered heterocycles [tBu2AlE(SiMe3)2]2 (E = Sb, 1; Bi, 2), whereas no reaction was observed with P(SiMe3)3. In contrast, the reaction of tBu2AlH with HP(SiMe3)2 also proceeds with elimination of Me3SiH and subsequent formation of [tBu2AlP(H)SiMe3]2 (3). Complexes 1–3 were characterized by multinuclear NMR (1H, 13C{1H}, 31P{1H}) and mass spectroscopy, elemental analysis, andsingle‐crystal X‐ray diffraction.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Synthesis and Characterization of Iron, Cobalt, and Nickel Complexes Bearing Novel N,N‐Chelate Ligands and Their Catalytic Properties in Ethylene Oligomerization
Authors: Wang Li , Zhang Cheng , Wang Zhong‐Xia
Published: May 2007

Treatment of o‐ROC6H4NC (R = PhCH2, iPr) with [Li{2‐CH(SiMe3)C5H4N}] afforded dimeric lithium complexes [Li{N(o‐ROC6H4)C(SiMe3)CH(2‐C5H4N)}]2 (3, R = PhCH2; 4, R = iPr). Reaction of the lithium complexes with 1 equiv. of (dme)NiCl2 gave nickel complexes [Ni{N(o‐ROC6H4)C(SiMe3)CH(2‐C5H4N)}2] (5, R = PhCH2; 6, R = iPr). The stoichiometric reaction of complexes 3 and 4 with Et3NH+Cl– formed 2‐{o‐ROC6H4NHC(SiMe3)CH}C5H4N (7, R = PhCH2; 8, R = iPr) in quantitative yields. Reaction of 7 or 8 with metal halides, including (dme)NiCl2, NiBr2, FeCl2·4H2O, and CoCl2 yielded complexes [MX2{(o‐ROC6H4)N=C(SiMe3)CH2(2‐C5H4N)}] (9, R = PhCH2, M = Ni, X = Cl; 10, R = iPr, M = Ni, X = Cl; 11, R = PhCH2, M = Ni, X = Br; 12, R = iPr, M = Ni, X = Br; 13, R = PhCH2, M = Fe, X = Cl; 14, R = iPr, M = Fe, X = Cl; 15, R = PhCH2, M = Co, X = Cl; 16, R = iPr, M = Co, X = Cl). For comparasion, nickel and cobalt complexes [MX2{(o‐MeC6H4)N=C(SiMe3)CH2(2‐C5H4N)}] (M = Ni, X = Br, 18; M = Co, X = Cl, 19) were similarly synthesized through reaction of 2‐{o‐MeC6H4NHC(SiMe3)CH}C5H4N (17) with NiBr2 and CoCl2, respectively. These compounds were characterized by NMR (for 3, 4, 7, 8, and 17) and IR (for 5–19) spectroscopy, elemental analyses and HRMS (for 5, 6, and 9–19). The molecular structures of complexes 3, 6, 12, and 14 were characterized by single‐crystal X‐ray diffraction techniques. The catalytic behavior in ethylene oligomerization of complexes 5, 6, 9–16, 18, and 19 was investigated. Under optimal conditions, the complexes showed good catalytic activities upon activation with appropriate aluminum co‐catalysts (8.72 × 102 to 18.2 × 102 kg/mol h atm for the nickel complexes upon activation with Et2AlCl and 4.3 × 102 to 8.1 × 102 kg/mol h atm for the iron and cobalt complexes upon activation with MMAO). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Cyclic Voltammetry in a Perfluorocarbon Emulsion Blood Substitute
Authors: Barlag Rebecca E. , Halsall H. Brian , Heineman William R.
Published: May 2007

Cyclic voltammetry in a perfluorocarbon emulsion based blood substitute (PEBS) was evaluated. The intent was to determine how PEBS affects the voltammetry of four representative electroactive compounds: potassium ferricyanide, ruthenium(II) trisbipyridine (rutris), hydroquinone, and 2,6‐dichloroindophenol (DCIP). Voltammograms in 0–20% PEBS‐Tris buffer mixtures are affected by PEBS, but reasonably well‐defined voltammograms are obtained in as much as 20% v/v. This report also shows that PEBS has only a small effect on amperometric detection of the reaction between DCIP and nicotinamide adenine dinucleotide (NADH), which has importance in clinical homogeneous immunoassays. Results support continued exploration of voltammetry/amperometry for quantitative analysis in this medium.
Determination of Cr(VI) in the Presence of Complexing Agents and Humic Substances by Catalytic Stripping Voltammetry
Authors: Grabarczyk Malgorzata , Kaczmarek Lukasz , Korolczuk Mieczyslaw
Published: May 2007

The voltammetric method of Cr(VI) determination in a flow system is proposed. Determinations can be carried out in the simultaneous presence of an excess of Cr(III), complexing agents, humic substances and surfactants. The method is based on the combination of a selective accumulation of the product of Cr(VI) reduction to the metallic state and a very sensitive voltammetric method of chromium determination in the presence of DTPA and nitrates. The calibration graph is linear from 1×10−9 to 5×10−8 mol L−1 for accumulation time of 30 s. The relative standard deviation is 5.2% (n=5) for Cr(VI) concentration 1×10−8 mol L−1. The influence of humic and fulvic acids, complexing agents and surfactants on Cr(VI) and the interfering Cr(III) signal is presented. The method was applied to Cr(VI) determination in certified reference material, soil sample, natural water sample and EDTA extracts from soil certified reference material.
Amperometric Urea Biosensor Using Aminated Glassy Carbon Electrode Covered with Urease Immobilized Carbon Sheet, Based on the Electrode Oxidation of Carbamic Acid
Authors: Wang Xiuyun , Watanabe Hiroaki , Sekioka Naoyuki , Hamana Hiroshi , Uchiyama Shunichi
Published: May 2007

A large oxidation current can be observed when ammonium carbamate aqueous solution is electrolyzed using a glassy carbon electrode (GCE) at a potential exceeding 1.0 V vs. Ag/AgCl and amino groups are introduced at the surface of the GCE. Aminated GCE exhibits the electrocatalytic activity of the oxidation of ammonium carbamate that is produced from urea as an intermediate product of urease reaction, and a distinct oxidation current is observed when the aminated GCE is used to oxidize the urea in the urease solution. A novel amperometric determination method to detect urea has been developed. This method is based on the electrooxidation of carbamic acid produced during urease reactions. Urease is immobilized to polymaleimidostyrene (PMS) coated on the insulated amorphous carbon sheet set on the aminated GCE surface. A good linear relationship is observed between urea concentration and the electrolytic current of the urease‐immobilized electrode in the concentration range from 0.5 mM to 21.0 mM. The proposed urea biosensor has an effective merit in that the interference resulting from ammonia and pH change caused by the urease reaction can be eliminated, differing from conventional urea biosensors.
Comparative Studies of Tridentate Sulfur and Nitrogen‐Containing Ligands as Ionophores for Construction of Cadmium Ion‐Selective Membrane Sensors
Authors: Singh Ashok Kumar , Mehtab Sameena , Singh Udai P. , Aggarwal Vaibhave
Published: May 2007

New polymeric membrane cadmium‐ion selective sensors have been prepared by incorporating nitrogen and sulfur containing tridentate ligands as the ionophores into the plasticized PVC membranes. Poly(vinyl chloride) (PVC) based membranes of potassium hydrotris[N‐(2,6‐xylyl)thioimdazolyl) borate] (KTt2,6‐xylyl) and potassium hydrotris(3‐phenyl‐5‐methylpyrazolyl) borate (KTpPh,Me) with sodium tetraphenyl borate (NaTPB) as an anionic excluder and dibutylphthalate (DBP), tributylphthalate (TBP), dioctylsebacate (DOS), and o‐nitrophenyloctyl ether (o‐NPOE) as plasticizing solvent mediators were investigated in different compositions. KTt2,6‐xylyl was found to be a selective and sensitive ion carrier for Cd(II) membrane sensor. A membrane composed of KTt2,6‐xylyl:NaTPB:PVC:DBP with the % mole ratio 2.3 : 1.1 : 34.8 : 61.8 (w/w) works well over a very wide concentration range (7.8×10−8–1.0×10−2 M) with a Nernstian slope of 29.4±0.2 mV/decades of activity between pH values of 3.5 to 9.0 with a detection limit of 4.37×10−8 M. The sensor displays very good discrimination toward Cd(II) ions with regard to most common cations. The proposed sensor shows a short response time for whole concentration range (ca. 8 s). The effects of the cationic (tetrabutylammonium chloride, TBC), anionic (sodium dodecyl sulfate, SDS) and nonionic (Triton X‐100) surfactants were investigated on the potentiometric properties of proposed cadmium‐selective sensor. The proposed sensor based on KTt2,6‐xylyl ionophore has also been used for the direct determination of cadmium ions in different water samples and human urine samples.
Covalent Labeling of Nucleosides with VIII‐ and VI‐Valent Osmium Complexes
Authors: Trefulka Mojmír , Ostatná Veronika , Havran Luděk , Fojta Miroslav , Paleček Emil
Published: May 2007

Osmium tetroxide complexes with nitrogen ligands [Os(VIII)L] have been widely applied as probes of the DNA structure and as electroactive labels of DNA. Here we describe the electrochemical behavior of Os(VIII)2,2‐bipyridine (Os, bipy)‐base‐labeled nucleosides. We show that electroactive label can be introduced also in the nucleoside ribose residues using six‐valent osmium complex. Cyclic voltammograms of sugar‐Os(VI)‐modified ribosides are similar but not identical to those of the base‐modified ribosides. Our results showing the electroactivity of sugar modified ribosides pave the way to facile end‐labeling of RNA.
DNA‐based nanofabrications
Authors: He Yu , Liu Haipeng , Chen Yi , Tian Ye , Deng Zhaoxiang , Ko Seung Hyeon , Ye Tao , Mao Chengde
Published: May 2007

Beyond its biological importance, short DNA sequences are of increasing interest as excellent and versatile building blocks, in material science and nanotechnology. DNA nanotechnology has been rapidly developed and has branched into several significantly different directions. Controlling DNA nanostructures is one of the most important branches, in which well‐defined static nanostructures are constructed from rationally designed DNA motifs. The diversity and complexity of such DNA nanostructures also endow them with promising applications in nanofabrications, nanoelectronics, biodiagnostics, and DNA computations. In this review, we will summarize our recent efforts in this direction. Microsc. Res. Tech., 2007. © 2007 Wiley‐Liss, Inc.
Microscopic measurement of the degree of mixing for nanoparticles in polymer nanocomposites by TEM images
Authors: Kim Dongsik , Lee Jun S. , Barry Carol M.F. , Mead Joey L.
Published: May 2007

For polymer nanocomposites, the small size of the fillers makes it difficult to analyze the degree of mixing quantitatively and often requires direct assessment via transmission electron microscopy (TEM). To date, qualitative comparisons and indirect measurements of the degree of mixing by measurement of certain properties are the most common methods. Better methods to quantitatively characterize the degree of mixing in nanocomposites would aid in studies investigating the effect of process conditions on the mixing behavior. Alumina/PET nanocomposites of identical composition, but with different degrees of mixing were prepared using a batch mixer. For evaluation of the degree of mixing with respect to both dispersion and distribution, three different techniques were applied and compared. TEM particle density was useful for dispersion, but did not adequately characterize distribution, while the Morisita's index gave poor results due to a wide range of effective particle sizes. Both methods ranked the samples differently compared to direct visual observation. In contrast, the skewness calculated by the quadrat method produced results consistent with visual rankings, and was found to be most effective in comparing and quantifying the degree of mixing. Although the quadrat method requires proper selection of quadrat size for a particular particle concentration, the skewness from the quadrat method was found to be most suitable as a standard index for the degree of mixing in nanocomposites. The usefulness of the quadrat method was verified using a second set of nanocomposites prepared by a twin screw extruder showing the potential for application of this technique for process development and quality control in commercial nanomanufacturing processes. Microsc. Res. Tech., 2007. © 2007 Wiley‐Liss, Inc.
Self‐organized nanotemplating on misfit dislocation networks investigated by scanning tunneling microscopy
Authors: Diaconescu Bogdan , Nenchev Georgi , Jones Joshua , Pohl Karsten
Published: May 2007

Self‐ordering growth of nanoarrays on strained metallic interfaces is an attractive option for preparing highly ordered nanotemplates. The great potential of this natural templating approach is that symmetry, feature sizes, and density are predicted to depend on the interfacial stress in these strained layers, which can be adjusted by changing the substrate‐thin film composition, temperature, and adlayer coverage. This bottom‐up approach of growing nanostructured two‐dimensional ordered arrays of clusters on the misfit dislocation networks of strained metallic thin films and surfaces requires a detailed understanding of the nucleation and film–adsorbate interaction processes. Here we show how high resolution, large scale, variable temperature scanning tunneling microscopy imaging can improve our understanding of these self‐assembly processes. Microsc. Res. Tech., 2007. © 2007 Wiley‐Liss, Inc.
Thermal, sonochemical, and mechanical behaviors of single crystal [60]fullerene nanotubes
Authors: Rauwerdink Kristen , Liu Jun‐Fu , Kintigh Jeremy , Miller Glen P.
Published: May 2007

Although related to conventional carbon nanotubes in both shape and construction, fullerene nanowhiskers and fullerene nanotubes have received far less attention. A modified liquid–liquid interfacial precipitation technique is described to produce relatively uniform batches of [60]fullerene nanotubes in high yield. Transmission electron microscopy (TEM) and atomic force microscopy (AFM) reveal that the tubes possess ∼100‐nm inside diameters and 300‐nm outside diameters. The [60]fullerene nanotubes degrade slowly at 180°C, eventually collapsing into micron scale [60]fullerene discs and rods, as revealed by optical microscopy and AFM. Ultrasonic cavitation chops [60]fullerene nanotubes into smaller segments within seconds. Longer ultrasonic bathing leads to considerable structural damage in which the sidewalls rupture. Mechanical stress tests using an AFM microscope tip effectively dent and break [60]fullerene nanowhiskers, revealing a hollow interior. Microsc. Res. Tech., 2007. © 2007 Wiley‐Liss, Inc.
High-order stimulated Raman scattering and cascaded nonlinear lasing effects in crystals of (χ(3)→ χ(2))-active orthorhombic PbB4O7
Authors: Kaminskii A A , Bohatý L , Becker P , Liebertz J , Bayarjargal L , Hanuza J , Eichler H J , Rhee H , Dong J
Published: May 2007

High-order stimulated Raman scattering (SRS) and cascaded χ(3)→ χ(2)generation effects in new nonlinear-laser crystals of PbB4O7were observed with picosecond laser pumping. All registered χ(3)- and χ(2)-lasing components in the visible and near-IR were identified and attributed to the SRS-promoting mode ωSRS≈ 148 cm-1of the studied crystal.
An Overview of Nano‐Polymers for Orthopedic Applications
Authors: Balasundaram Ganesan , Webster Thomas J.
Published: May 2007

This review paper presents many exciting nanotechnology and tissue engineering approaches involving polymers that have enormous potential impact on human health care, particularly for orthopedic applications. As scaffolds play a vital role in tissue engineering, the feasibility of designing polymeric nano‐featured scaffolds is reviewed. Although bone is a very diverse tissue providing different functions within the body, recent work has resulted in new biomaterials with promise to solve orthopedic problems. Significant advancements in orthopedic care are required since recent data highlight a less than 15 year lifetime of current hip implants. Nanotechnology (or the use of nanomaterials) is providing a wide range of new materials to improve the current short lifetimes of orthopedic implants.

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Bone Regeneration on Macroporous Aqueous‐Derived Silk 3‐D Scaffolds
Authors: Kim Hyeon Joo , Kim Ung‐Jin , Leisk Gary G. , Bayan Christopher , Georgakoudi Irene , Kaplan David L.
Published: May 2007

Spinner flask culture under osteogenic conditions was used to study osteogenic outcomes from human bone marrow‐derived mesenchymal stem cells (hMSCs) seeded on aqueous‐derived porous silk scaffolds. Of particular novelty was the use of larger sized scaffolds (15 mm diameter, 5 mm thick) and large pore sizes (≈900–1 000 micron diameter). Cultures were maintained for 84 d in the spinner flasks and compared to static controls under otherwise similar conditions. The spinner flask cultures demonstrated enhanced cell proliferation compared to static cultures and the improved fluid flow promoted significantly improved osteogenic related outcomes based on elevated alkaline phosphatase (ALP) activity and the deposition of mineralized matrix. The expression of osteogenic differentiation associated markers based on real time PCR also demonstrated increased responses under the dynamic spinner flask culture conditions. Histological analysis showed organized bone‐like structures in the constructs cultured in the spinner flasks after 56 d of culture. These structures stained intensely with von Kossa. The combination of improved transport due to spinner flask culture and the use of macroporous 3D aqueous‐derived silk scaffolds with large pore sizes resulted in enhanced outcomes related to bone tissue engineering, even with the use of large sized scaffolds in the study. These results suggest the importance of the structure of the silk biomaterial substrate (water vs. solvent based preparation) and large pore sizes in improved bone‐like outcomes during dynamic cultivation.

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Random processes of Hausdorff rectifiable closet sets
Authors: Zähle M.
Published: April 2007

Problems of intersections of processes of HAUSDORFF rectifiable closed sets in Rn are studied. The first part deals with integral geometric fundamentals and questions of measurability. In the second part the stochastic approach is given.
A Cauchy integral formula for a class of elliptic systems of partial differential equations of first order in the space
Authors: Goldschmidt Bernd
Published: April 2007

This paper is a continuation of [6]. Here we construct a CAUCHYintegral formula and a POMPEJU‐representation for elliptic systems of partial differential equations of first order inRn, which may be described with the help of a CLIFFORD‐algebra. Moreover we study properties of the fundamental kernels and jump‐integrals.
On the index of degenerate pseudodifferential operators on a closed curve
Authors: Elschner Johannes
Published: April 2007

We consider a class of degenerate classical pseudodifferential operators on a closed curve and compute their index in Sobolev spaces. The index is expressed as a winding number by means of the principal and the subprincipal symbol. Furthermore, applications to the smoothness of solutions and the degenerate oblique derivative problem in the plane are given.
Cutting and Pasting of Elliptic Operators
Authors: Booss Bernhelm , Rempel Stephan
Published: April 2007

IfA : C∞E → C∞Fis an elliptic operator between sections of vector bundlesE, Fover a closed smoothn‐manifoldX, Ya smooth (n– 1)‐submanifold ofXwith trivial normal bundle, and Ψ = (ΨE, ΨF) a pair of automorphisms ofE|YandF|Yinducing a diffeomorphismfofYand commuting with the principal symbol σAofAoverY, then an elliptic operatorAΨis (uniquely up to operators of lower order) defined between sections of vector bundlesEΨ,FΨover a closed manifoldXf, all obtained by cutting and pasting the respective objects alongY. The difference indexAΨ– indexAis investigated and the relations with additivity properties of topological invariants and with classical transmission problems are explained.
Short maximal chains in the lattice of clones over a finite set
Authors: Szendrei Ágnes
Published: April 2007

Let ℒ︁k (3 ≦ k < ℵ0) denote the lattice of clones of finitary operations on a k‐element set. One interesting characteristic of the uncountable lattice ℒ︁k is the minimum lk of the cardinalities of maximal chains in ℒ︁k. It is known that for k prime lk = 5. In this paper the 5‐element maximal chains contained in ℒ︁k are investigated. It is proved that for k composite lk ≧ 6 while for k prime there are exactly (k–2)! (k + 4) 5‐element maximal chains in ℒ︁k, each closely related to a group operation.
Zur Gleichung der Fläche mit gegebener mittlerer Krümmung in zweidimensionalen eckigen Gebieten
Authors: Miersemann Erich
Published: April 2007

We prove an existence theorem and regularity properties up to the boundary of the noparametric DIRICHLET problem for the surface with prescribed mean curvature in two‐dimensional domains with corners.
Approximation of First Exit Times of Diffusions and Approximate Solution of Parabolic Equations
Authors: Platen Eckhard
Published: April 2007

In the paper the first exit time of a diffusion from a bounded region is approximated by first exit times of time discrete diffusion approximations. Their speed of convergence is estimated with respect to the maximum step size. Finally, this result is applied for the construction of approximate solutions of degenerate parabolic equations which can be used in Monte‐Carlo simulation algorithms.
On Spline Collocation for Singular Integral Equations
Authors: Schmidt G.
Published: April 2007

This paper is devoted to the approximate solution of one‐dimensional singular integral equations on a closed curve by spline collocation methods. As the main result we give conditions which are sufficient and in special cases also necessary for the convergence in SOBOLEV norms.

The paper is organized as follows. In chapter 1 we indicate some definitions and some facts about projection methods. In chapter 2, we generalize a technique developed in [1] and study the convergence of collocations using splines of odd degree in periodic SOBOLEV spaces. In chapter 3, we apply our method to collocations by splines of even degree and consider the case of systems of equations. And in the last chapter, 4, the results are applied to singular integral equations and compared with known facts about piecewise linear spline collocation for such equations.
The PENROSE Transform for Bundles Non‐Trivial on the General Line
Authors: Leiterer Jürgen
Published: April 2007

Let L0 be a fixed projective line in
CP3 and let M ≅ C4 be the complexified MINKOWSKI space interpreted as the manifold of all projective lines L ⫅ CP3 with L ∩ L0 ∅︁ Ø. Let D ⫅ M, D′ ⫅ CP3/L0 be open sets such that \documentclass{article}\pagestyle{empty}\begin{document}$ D' = \mathop \cup \limits_{L \in D} $\end{document}. Under certain topological conditions on D, R. S. WARD'S PENROSE transform sets up an 1–1 correspondence between holomorphic vector bundles over D′ trivial over each L ϵ D and holomorphic connections with anti‐self‐dual curvature over D (anti‐self‐dual YANG‐MILLIS fields). In the present paper WARD'S construction is generalized to holomorphic vector bundles E over D′ satisfying the condition that \documentclass{article}\pagestyle{empty}\begin{document}$ E|_L \cong E|_{\tilde L} $\end{document} for all \documentclass{article}\pagestyle{empty}\begin{document}$ L,\tilde L \in D $\end{document}.
On Weak Convergence of Hypermeasures
Authors: Haase Hermann
Published: April 2007

Measures on the hyperspace of the closed sets with the FLACHSMEYER‐FELL topology are completely defined by their capacities. A necessary and sufficient condition is given for the weak convergence of a sequence of positive bounded σ‐additive measures on the hyperspace in terms of their capacities.
Locally Complemented Subspaces and ℒ︁p‐Spaces for 0 < p < 1
Authors: Kalton N. J.
Published: April 2007

We develop a theory of ℒ︁p‐spaces for 0 < p < 1, basing our definition on the concept of a locally complemented subspace of a quasi‐BANACH space. Among the topics we consider are the existence of basis in ℒ︁p‐spaces, and lifting and extension properties for operators. We also give a simple construction of uncountably many separable ℒ︁p‐spaces of the form ℒ︁p(X) where X is not a ℒ︁p‐space. We also give some applications of our theory to the spaces Hp, 0 < p < 1.
Some Properties of Certain Multivalent Functions
Authors: Owa Shigeyoshi
Published: May 2007

Certain subclasses 𝒜p(j, α), ℬ︁p(j, α) and 𝒢p,b(j, α) of multivalent functions in the unit disk are introduced. The object of the present paper is to derive some properties of functions belonging to the classes 𝒜p(j, α), ℬ︁p(j, α), or 𝒢p,b(j, α). Further, generalizations of results for certain multivalent functions by M. NUNOKAWA, S. OWA and H. SAITOH [9], and by R. SINGH and S. SINGH [13] are shown.
Strict and Mixed Topologies on Function Spaces
Authors: Prieto Angeles
Published: May 2007

In this paper we prove that the strict topology on spaces of continuous and holomorphic functions on a BANACH space can be considered a mixed topology. Using this fact, we obtain new results about the strict topology, as an application of the general properties of mixed topologies.
Multidimensional Modified Fractional Calculus Operators
Authors: Tuan Vu Kim , Saigo Megumi
Published: May 2007

This paper deals with the study of some new multidimensional operators of fractional calculus. These operators are considered in certain spaces of test and generalized functions. Some mapping properties and product rules are obtained.
On a Problem by J. M. Wills
Authors: Sauer Peter
Published: May 2007

Let P1(n), P2(n), P3(n) denote the norm‐polyhedra cube, crosspolytope and sphere in the Euclidean n‐space. We consider the polyhedra Di,j(n):=Pi(n)∩Pj(n) with 1 ≦ i ≠ j ≦ 3. In [2] posed the question about the limits \documentclass{article}\pagestyle{empty}\begin{document}$\mathop {\lim }\limits_{n \to \infty } $\end{document} V(Di,j(n)) of the volumes of the polyhedra Di,j(n). WEISSBACH gave the answer for one of them, namely \documentclass{article}\pagestyle{empty}\begin{document}$\mathop {\lim }\limits_{n \to \infty } $\end{document} V(D1,2(n)). A more general result used Banach‐space methods of Schechtman and ZINN contains the solution for the limits \documentclass{article}\pagestyle{empty}\begin{document}$\mathop {\lim }\limits_{n \to \infty } $\end{document} V(Di,j(n)). The main result of this paper is the determination of both limits \documentclass{article}\pagestyle{empty}\begin{document}$\mathop {\lim }\limits_{n \to \infty } $\end{document} V(D1,3(n)) and \documentclass{article}\pagestyle{empty}\begin{document}$\mathop {\lim }\limits_{n \to \infty } $\end{document} V(D2,3(n)) with geometrical methods.
An Interface Problem in Solid Mechanics with a Linear Elastic and a Hyperelastic Material
Authors: Carstensen Carsten
Published: May 2007

The three dimensional interface problem is considered with the homogeneous Lamé system in an unbounded exterior domain and some quasistatic nonlinear elastic material behavior in a bounded interior Lipschitz domain. The nonlinear material is of the Mooney‐Rivlin type of polyconvex materials. We give a weak formulation of the interface problem based on minimizing the energy, and rewrite it in terms of boundary integral operators. Then, we prove existence of solutions.
Comparison Theorems for Functional Differential Equations
Authors: Džurina Jozef
Published: May 2007

Our aim in this paper is to obtain the comparison principles which extend those of Grace and LALLI. The equations.

Lnu(t)±f(t, u[g(t)]= 0

are compared with the equations.

Mnu(t)±z(t)h([τ(t)])= 0.
A Solution of the Matrix Problem for Rickart C*‐Algebras
Authors: Ara Pere , Goldstein Dmitry
Published: May 2007

We prove that matrix algebras over a Rickart C*‐algebra are also Rickart C*‐algebras. As a consequence of this, every Rickart C*‐algebra is an UMF‐algebra and satisfies polar decomposition.
Complements on Diminnie Orthogonality
Authors: Alonso Javier , Benítez Carlos
Published: May 2007

A new orthogonality relation for normed linear spaces is introduced by C. R. DIMINNIE in [10]. Some interesting properties of such orthogonality and its relationship with Birkhoff orthogonality are studied in the above paper.

The first part of this paper begins with a geometrical interpretation of Diminnie‐orthogonality which allows us to obtain some other properties of such orthogonality. The second part deals with relationships between Diminnie orthogonality and some other known orthogonalities.
Connection Formulas for Second Order Differential Equations with a Complex Parameter and Having an Arbitrary Number of Turning Points
Authors: Eberhard W. , Freiling G. , Schneider A.
Published: May 2007

We consider the differential equation

on a finite interval I, where I contains m turning points, that is here, zeros of ϕ. Using asymptotic estimates proved by R. E. LANGER for solutions of (*) for intervals containing only one turning point we derive asymptotic estimates (for ρ → ) for a special fundamental system of solutions of (*) in I. The results obtained are fundamental for the investigation of eigenvalue problems defined by (*) and suitable boundary conditions.
Photopolymerization and Characteristics of Polyurethane/Organoclay Nanocomposites
Authors: Tan Hailin , Nie Jun
Published: May 2007

Different polymerizable ammonium surfactants were successfully synthesized via Michael‐addition and quaternarization reactions. Organoclays containing reactive methacrylate groups were prepared by the cationic exchange process. Intercalated nanocomposites were produced by UV initiated polymerization with 5 wt.‐% organophilic clay loading. DMTA tests and tensile analysis implied that a long chain polymerizable modifier could crosslink with the polymer matrix, and mechanical and tensile properties were enhanced dramatically about 80%. Water sorption was not elevated, which was determined by the polymer itself and the hydrophobicity of the modifier, although the water permeation was improved.

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Pudendal entrapment as an etiology of chronic perineal pain: Diagnosis and treatment
Authors: Popeney Charles , Ansell Van , Renney Ken
Published: May 2007

Aims

This study was conducted to evaluate pudendal entrapment as an etiology of chronic pain, a diagnostic protocol for pudendal entrapment, and clinical response to surgical decompression.

Methods

A case series of 58 consecutive patients with a diagnosis of pudendal entrapment, based on clinical factors, neurophysiologic studies, and response to pudendal nerve infiltrations, is described. All patients were refractory to other treatment modalities. Patients were assessed before and after surgical decompression: degree of pain was assessed by visual analog scale (VAS) score, percent global overall improvement, and improved function and quality of life before surgery and 12 months or longer after surgery.

Results

The primary presenting feature was progressive, chronic, intractable neuropathic pain in the perineum (ano‐rectal and/or urogenital) that worsened with sitting. Other symptoms included urinary hesitancy, frequency, urgency, constipation/painful bowel movements, and sexual dysfunction. After surgical decompression, 35 (60%) patients were classified as responders, based on one of the following three criteria: a greater than 50% reduction in VAS score, a greater than 50% improvement in global assessment of pain, or a greater than 50% improvement in function and quality of life.

Conclusions

Pudendal entrapment can be a cause of chronic, disabling perineal pain in both men and women. Since symptomatic patients seek medical care from many different medical specialists, a reliable diagnostic protocol should be established. For patients refractory to conventional interventions, surgical decompression of the pudendal nerve can improve pain‐related symptoms and disability. With ongoing work on this subject, which is a difficult disorder to accurately diagnose and treat, a better awareness of pudendal entrapment across specialties will emerge. Neurourol. Urodynam. 26:820–827, 2007. © 2007 Wiley‐Liss, Inc.
Antidiuresis therapy: Mechanism of action and clinical implications
Authors: Nørgaard Jens Peter , Hashim Hashim , Malmberg Lars , Robinson Dudley
Published: May 2007

Abnormalities of micturition occur in many different diseases, have a variety of causes and take several forms. This review will focus exclusively on those abnormalities in which antidiuretic therapy may be of benefit. These conditions are primarily characterized by an increase in the total amount of urine produced (polyuria) or a circadian shift in the control of urine production and/or voiding (nocturnal enuresis, nocturia). Neurourol. Urodynam. 26:1008–1013, 2007. © 2007 Wiley‐Liss, Inc.
Effect of clay content on the ultraviolet‐curing and physical properties of urethane‐acrylate/clay nanocomposites
Authors: Lee Jong Min , Kim Dae Su
Published: May 2007

The effect of clay content on the ultraviolet (UV)‐curing behavior and physical properties of a urethane‐acrylate/clay nanocomposite system was studied. The UV‐curing behavior of the nanocomposite system was investigated by monitoring the change of a characteristic IR absorption peak for acrylate groups. The UV‐curing rate and final conversion of the nanocomposite system increased with increasing clay content and affected the physical properties of the nanocomposites. The thermal, mechanical and optical properties of the nanocomposites were affected by clay content. The X‐ray diffraction (XRD) patterns and transmission electron microscopy (TEM) image showed that the nanocomposites had an intercalated structure. POLYM. COMPOS., 28:325–330, 2007. © 2007 Society of Plastics Engineers
Effect of compatibilizer on the natural durability of wood flour/high density polyethylene composites against rainbow fungus (Coriolus versicolor)
Authors: Karimi Ali Naghi , Tajvidi Mehdi , Pourabbasi Sara
Published: May 2007

To evaluate the effect of compatibilizer on the natural durability of wood flour/high density polyethylene composites against Coriolus versicolor, composites containing 25% and 50% by weight maple wood flour and 1% and 2% compatibilizer (Maleic anhydride polyethylene (MAPE)), respectively, were sampled. Identical specimens of the same composites without the compatibilizer were also prepared. Physical and mechanical properties of all specimens, including water absorption, flexural modulus, flexural strength, impact strength and hardness, were determined prior to and after incubation with the fungus for 14 weeks at 25°C and 75% relative humidity. Weight losses of the specimens were also determined after incubation. Results indicated that the compatibilizer had significant effects on the natural durability of the studied composite formulations so that all mechanical properties were affected by the fungus to greater extents in the case of uncompatibilized specimens than the compatibilized ones. Weight loss of the uncompatibilized composites was also higher than that of compatibilized ones. Higher water absorption was observed in all cases after incubation. However, the increase in water absorption was considerably higher in the case of uncompatibilized specimens. POLYM. COMPOS., 28:273–277, 2007. © 2007 Society of Plastics Engineers
Photochemical micelle control by long‐alkyl‐chain Malachite Green
Authors: Uda Ryoko M. , Kimura Keiichi
Published: April 2007

We have designed a Malachite Green leuconitrile carrying a long‐alkyl‐chain which controls micelle formation photochemically. The Malachite Green derivative, when ionized photochemically, exhibits some hydrophilicity by its triphenylmethyl cation and some hydrophobicity by its long alkyl chain. The behavior of the photoresponsive Malachite Green surfactant was studied in mixed micelle solutions containing cetyltrimethylammonium chloride (CTAC) and a small quantity of the Malachite Green. We found that UV irradiation drastically decreased the critical micelle concentration (cmc) of the mixed micelle solutions and that the Malachite Green derivative realized photoinduced uptake of oily substances based on its photogenerated amphiphilicity. The mechanism of the photoinduced enhancement of solubilizing oily substances is discussed at the viewpoint of the microscopic location of the Malachite Green surfactant in the micelle. Copyright © 2007 John Wiley & Sons, Ltd.