bluuebunny/crossref_metadata_2025 huggingface dataset:
On Relative Precision in Stratified Sampling for a Mean with Fixed Cost
Authors: Bennett B. M. , Islam M. A.
Published: May 2007

This paper considers the extrema of the relative precision (R. P.), or the ratio of the variance of optimum allocation to that of proportional allocation in stratified sampling for a mean (=Y) or total (=Y) when there is a fixed cost C=co+σnhch over L strata. The upper bound of R. P. is shown to be equal to unity, though the lower bound can be negative while approaching zero if the finite population size N→∞. Numerical results (cf. Table) when the upper bound of R. P. = 1 is attained are included for the cases L≦4 with various combinations of {Wh}, {ch} and a fixed cost C; these give the appropriate sample sizes (=np) determined for proportional sampling in the cases of finite populations of sizes N=5000, 10,000 respectively.
On Analysis of Covariance Under Heteroscedasticity and Robustness with Respect to Departure from Normality
Authors: Tan W. Y.
Published: May 2007

In this paper we consider a covariance model under heteroscedastic variances and propose a procedure for testing treatment effects. A simultaneous procedure for comparing the treatment effects is also developed. Some Monte Carlo studies indicate that the effects of departure from normality may not be very serious although some effects do exist due to high level of heteroscedasticity.
The Doubly Noncentral Distribution of Wilks' Statistic in MANOVA
Authors: Gill D. S. , Siotani Minoru
Published: May 2007

When plot effects are modeled in a randomized block design in multivariate analysis of variance the error and hypothesis matrices have independent noncentral Wishart distributions. This gives rise to doubly noncentral distribution of Wilks' statistic. The doubly noncentral distribution of Wilks' statistics, when the noncentrality matrices for the noncentral Wishart distributions in the above setting are of rank one or two, is investigated.
Decompositions for 2‐Ratios‐Parameter Symmetry Model in Square Contingency Tables with Ordered Categoriesat
Authors: Tomizawa Sadao
Published: May 2007

For square contingency tables with ordered categories, Agresti (1983) considered the linear diagonals‐parameter symmetry model. An extended model including that model is proposed which has only one more parameter than that model. The model also includes the conditional symmetry model considered by McCullagh (1978). Decompositions for the proposed model and Agresti's model are given.
A Simple Survival Model for Combined Action of Two Damaging Agents
Authors: Tanushev M. , Myasnikova E. M. , Yakovlev A. Yu.
Published: May 2007

The aim of this study was mathematical formalization of the development of two damage processes in response to the combined action of two different damaging agents. The model allows to obtain the parametric family of distributions for the life‐span when the organism's death is due to joint effect of two damage processes. Differing by their probabilistic meaning the notions of a priori (M(t)) and a posteriori (M(y)) conditional mean contributions of each damage process to the final effect of combined injury are introduced. The formulas permitting to compute theMandMvalues on the basis of survival data parametric analysis are given.
Analysis of Nested Designs with Binomially‐Distributed Outcome Variables
Authors: Le Chap T.
Published: May 2007

A model and methods are presented for the analysis of a nested design with binomially‐distributed outcome variables. The proposed method may also be applicable to the analysis of singly‐ordered contingency tables.
Associated LAH Numbers, Factorial Series Distributions and Unbiased Estimation of a Size Parameter
Authors: Berg S.
Published: May 2007

A finite population consists of kN individuals of N different categories with k individuals each. It is required to estimate the unknown parameter N, the number of different classes in the population. A sequential sampling scheme is considered in which individuals are sampled until a preassigned number of repetitions of already observed categories occur in the sample. Corresponding fixed sample size schemes were considered by Charalambides (1981). The sequential sampling scheme has the advantage of always allowing unbiased estimation of the size parameter N. It is shown that relative to Charalambides' fixed sample size scheme only minor adjustments are required to account for the sequential scheme. In particular, MVU estimators of parametric functions are expressible in terms of the C‐numbers introduced by Charalambides.
Information in Observation Under the Correlated Linear Model
Authors: Ghosh Subir
Published: May 2007

In this paper we propose a measure of information in a set of observations under a given design and the linear model with the observations being correlated. We then compare the different sets of observations with respect to the information measure in the situations where the underlying designs are nested and split‐plot.

AMS 1970 Subject Classification: Secondary 62J05, 62J10, 62K05, 62K10, 62K15, 62K99.
Relating Cox's Proportional Hazard Model to the Exponential Model for Survival
Authors: Maller R. A.
Published: May 2007

An approximate representation is given for the partial likelihood estimate of the regression coefficient in Cox's proportional hazard model which indicates how it measures the association between survival time and covariate. The case of a single covariate is concentrated on. The representation is closely related to the first step of a Newton‐Raphson iteration, i.e. to the score test. A similar representation for the Feigl‐Zelen exponential model shows that a similar type of association is being measured, if observed lifetimes are interpreted as expected lifetimes of ordered exponentials. Necessary and sufficient conditions for the existence of Cox's estimate in the simple case are also written down.
Some Remarks About “Mortality of a Heterogeneous Cohort; Description and Implications”
Authors: Hougaard Philip
Published: May 2007

It is pointed out that the results of Vaupel et al. (1979) on mortality for heterogeneous populations are correct and thus it is not correct of Nour (1984) to claim that the results are faulty.
Estimation and Tests for Departures from Rao‐Structured Covariance Matrices
Authors: Ghosh Subir , Gokhale D. V.
Published: May 2007

For linear models, a measure of departure of a variance‐covariance matrix from Rao‐structure (Rao, 1967) is proposed. Relevant estimation and testing problems are discussed. Illustrative examples are also presented.
Assessing the Effect of the Best Treatment. A Non‐parametric Inference Problem
Authors: Lanke Jan
Published: May 2007

For patients of a certain type, a number of treatments are available. The effect of each such treatment is assumed to be described by a shift model; it is, however, admitted that there may be an interaction between patient and treatment, meaning in particular that the treatment which is best for one patient is not necessarily best for another. The problem is the following: if each patient is given the treatment which is optimal for that particular patient, will this produce a significant effect and, if so, how large is the effect?
Estimation of Error Rates by Means of Simulated Bootstrap Distributions
Authors: Wernecke K.‐D. , Kalb G.
Published: May 2007

The bootstrap error estimation method is investigated in comparison with the known π‐method and with a combined error estimation suggested by us using simulated and normally distributed “populations” in 15 and 30 characters, respectively. For small sample sizes (below the double to threefold number of characters per class) the estimates resulting from the bootstrap method are on the average too small and can no longer be accepted. Significantly better results (with an essentially lower calculation expenditure) are obtained for the π‐method and the combined estimation. The variability is essentially the same for all the three methods.

This applies both in the case of rather badly separated and in the case of very well separated populations.

A bootstrap estimation modified by us also gives unsatisfactory results.
A Growth Curve Analysis for Bulls Tested at Station
Authors: Liski E. P.
Published: May 2007

Data on 2712 bulls tested at station were analysed to study the effect of certain external variables on growth traits of bulls. Most of the animals were Ayrshires (2136). Otherwise Finncattle bulls and Frisian bulls were involved. The testing covers the interval 60–365 days of age, although in part of the data the period is 30–365. Bulls were weighted every 30th day (between 1965 and 1970), or at the ages of 60 and 180 days, and thereafter every 30 days up to the age of 365 days (between 1971 and 1977). Also birth weight was available for 1250 calves. Feeding and general treatment of bulls at station was as uniform as possible for all animals. Conseqúently it can be assumed that effects of non‐genetic factors on the growth traits of bulls are minimized.

One of the objectives of this study was to compare the growth curves for the three breeds. In our data measurements at certain time‐points have dropped out during the course of data collection.

Therefore we study the influence of deleting measurements. We also consider the problem of influential measurements at both the design level and the inference level. Several types of growth curves are fitted to the data in order to find the most appropriate model.
On Some Problems in Measuring Change on Ordinal Data
Authors: Krause B. , Raykov T.
Published: May 2007

Two designs frequently occurring in biomedicine and social sciences are considered—the “experts”/“objects”—design consisting in ranking M fixed “objects” by each of N “experts” before and after an intervention, and the rating‐scale‐design in which N judges are asked to assign one of K given lables, constituting the rating‐scale, before and after an intervention. Nonparametric test procedures are proposed for evaluating the treatment effect.
The Analysis of Partial Diallel Crosses
Authors: Ceranka B. , Dobek A. , Kiełozewska H.
Published: May 2007

The analysis of offsprings from the partial diallel crosses is presented. In considered type of crossing,pparental forms intoHseparate groups are devided. Single crosses among parental forms, from separate groups only, are performed. The analysis for experiments laid out in efficiency balanced block designs is given.
Probability of Obtaning Negative Estimates of Heritability from Full‐Sib Analysis under a General Model of Gene Action
Authors: Prabhakaran V. T. , Jain J. P.
Published: May 2007

Formulae are derived for the probability of obtaining negative estimates of heritability (h2) in full‐sib analysis under the additive‐dominance‐epistasis model of gene action. Evaluation of the probabilities was undertaken for several combinations of sire/dam number, h2 and proportions of dominance and additive X additive epistatic variances, assuming two full‐sibs per mating and that the dominance related epistasis is absent. In the light of the results, minimum sample sizes for obtaining admissible estimates from sire, dam components and their combination have been prescribed.
Bayes Estimator of Survival Probability from Randomly Censored Observations with Weibull Distribution of Time to Death
Authors: Pandey M.
Published: May 2007

This paper deals with Bayes estimation of survival probability when the data are randomly censored. Such a situation arises in case of a clinical trial which extends for a limited period T. A fixed number of patients (n) are observed whose times to death have identical Weibull distribution with parameters β and θ. The maximum times of observation for different patients are also independent uniform variables as the patients arrive randomly throughout the trial. For the joint prior distribution of (β, θ) as suggested by Sinha and Kale (1980, page 137) Bayes estimator of survival probability at time t (0<t<T) has been obtained. Considering squared error loss function it is the mean of the survival probability with respect to the posterior distribution of (β, θ). This estimator is then compared with the maximum likelihood estimator, by simulation, for various values of β, θ and censoring percentage. The proposed estimator is found to be better under certain conditions.
Rank Tests for the 2×2 Design with I Blocks
Authors: Haux R. , Mattauch V. , Weckesser G.
Published: May 2007

In this paper we suggest rank tests for main effects and for interaction when there are two factors and two levels within each factor and when, in addition, there are I blocks. The asymptotic distributions of the test statistics under H0 are derived. The application of the tests is illustrated by an example and a simulation study investigates size and power of the tests.
Approximate Methodologies for Proportional Mortality Analyses in Epidemiologic Studies Involving Competing Risks of Death Regardless of their Covariance Structure
Authors: Rao B. Raja , Marsh Gary M.
Published: May 2007

The present paper discusses methodologies for proportional mortality analyses in epidemiologic studies in which an individual is exposed simultaneously to several (say M) risks of death which compete for his life. A general situation is considered where nothing is known about the dependence or covariance structure among the risks. The available data consist only of the number of deaths in each stratum of the test population, but not the number of individuals at risk. A general class of approximate simultaneous confidence and prediction intervals are developed which provide overall risk assessment of the competing risk factors in many biomedical and epidemiologic studies. Our paper describes how, under reasonable assumptions, asymptotically precise inferences may be based on proportional mortality analyses in order to estimate the indirectly and the externally standardized cause‐specific risk measures RSMRi and RSRRi respectively.

The tuberculosis mortality data of Kupper, et al., (1978) and the respiratory cancer mortality data of Enterline and Marsh (1983) are utilized to illustrate the usefulness of our results. Methodologies are presented to construct simultaneous confidence intervals for RSMRi involving SPMRi and simultaneous prediction intervals for RSRRi involving SePMRi. Both Scheffé‐and Sidak‐Types of simultaneous intervals are constructed for M competing risks of death. As a particular case if M = 1, i.e., if the risks of death may be assumed to be independent, as is usually done in proportional mortality analyses, the Scheffé and Sidak confidence intervals become identical and are narrower than of Kupper et al., (1978). In this sense, our paper generalizes the methodologies of proportional mortality analyses in two directions, first to discuss the situation involving competing risks, and second to obtain narrower confidence intervals.
Utilizing Cause‐of‐Death Information to Estimate Conditional Probabilities of Disease and Death
Authors: Kodell Ralph L.
Published: May 2007

Conditional probabilities that do not require the assumption of independence among competing risks for identifiability are proposed for the analysis of carcinogenesis bioassay data as a reasonable adjustment for deaths or other removals due to competing risks. These conditional probabilities permit consideration of one type of tumor at a time, but in such a way that inferences are relevant to actual experimental conditions under which other diseases and causes of death are present and operating. The importance of assigning cause of death in bioassays is demonstrated by the fact that it allows the definition and identification of functions useful in the interpretation of carcinogenesis data, without requiring that a disease of interest be independent from competing risks. However, one proposed conditional probability does require sacrifice data for its identifiability.
Using a Generalized Mean as a Measure of Location
Authors: Taylor Jeremy M. G.
Published: May 2007

In Taylor (1985 a) a measure of location, akin to a generalised mean was proposed, it's properties were studied for a particular family of skew distributions. The measure of location is essentially the retransformed mean after first transforming the observations to an approximately symmetric scale. Here it's properties are investigated for more general skew distributions. In particular, we study whether it satisfies the axioms for measures of location given in Bickel and Lehmann (1975). We show that it is estimating approximately the distribution median and through simulations we show that it is more efficient than the sample median.
Analysis of Colony‐Forming Ability of Human Fibroblast Strains by Linear Regression
Authors: Edler Lutz , Thielmann Heinz Walter
Published: May 2007

A linear regression approach is presented for the statistical analysis of dose‐response curves obtained by measuring the colony‐forming ability of human fibroblast strains. The crucial determination of the dose range in which the linear model can be assumed is achieved by a combination of statistical criteria and biological claims. As a basic quantitative parameter we investigate the slope of the regression line and, by taking reciprocals, we retransform it into the biologically established parameter D0. Several methods for the combination of estimates are presented.
Normal Approximations of Exact Tests in Configural Frequency Analysis
Authors: Bergman L. R. , von Eye A.
Published: May 2007

The most common tests for types and antitypes in configural frequency analysis are normal approximations of exact tests. In the paper such statistics under the complete independence model and under the fixed margins model are discussed. It turns out that these test statistics are not acceptable when the number of simultaneously performed tests is large or when the expected frequencies are small. In these cases, the use of exact tests is advocated and some existing computer programs for such tests are indicated. A normal approximation based on the strong version of the De Moivre‐Laplace limit theorem is also discussed. Empirical examples are given from longitudinal data describing psychological development of boys.
The Hyper‐Negative Binomial Distribution
Authors: Yousry M. A. , Srivastava R. C.
Published: May 2007

A generalized family of the negative binomial distribution is introduced in a paper by Srivastava, Yousry and Ahmed (1986). It is a solution of the difference equation
equation image
and is called the hyper‐negative binomial distribution. Certain properties including the moments of the distribution are presented. Moment estimators of the parameters are obtained and goodness of fit is illustrated for chromatid aberration data.
Estimation of Growth Norms from Incomplete Longitudinal Data
Authors: Woolson Robert F. , Clarke William R.
Published: May 2007

Longitudinal studies are rarely complete due to attrition, mistimed visits and observations missing at random. When the data are missing at random it is possible to estimate the primary location parameters of interest by constructing a modification of Zellner's (1962) seemingly unrelated regression estimator. Such a procedure is developed in this paper and is applied to a longitudinal study of coronary risk factors in children. The method consists of two stages in which the covariance matrix is estimated at the first stage. Using the estimated covariance matrix a generalized least squares estimator of the regression parameter vector is then determined at the second stage. Limitations of the procedure are also discussed.
Randomization and Additivity in the Two‐Period Crossover Clinicial Trial
Authors: McHugh Richard , Gomez‐Marin Orlando
Published: May 2007

In certain areas of medical research, the two‐period crossover design is a frequent choice for comparing treatments A and B in a randomized clinical trial. Earlier work by Grizzle and by Brown was based upon a parametric theory linear model. Recently, the present authors employed D. R. Cox's additive randomization models and, for the case of zero residual effect, found a discrepancy between it and the parametric model with respect to the precision of period effects. In the present note, this divergence is accounted for by allowing for the possibility of non‐additivity through the use of a completely general randomization model. It is concluded that the structure of the crossover design is such that use of the parametric theory linear model is required if a single, consistent model is desired.
Analysis of Multiply Matched Retrospective Studies When Risk Factor Under Study is Discrete, With Two or More Levels
Authors: Ejigou Ayenew
Published: May 2007

The odds ratio is known to closely approximate the relative risk when the disease is rare. Logistic regression models are often used to estimate such odds ratios, but here a different model is used which avoids the assumptions implicit in logistic modelling; it also has the advantage of providing a test of homogeneity for odds rat os in situations where the logistic model cannot.
Estimation of Relative Risk Under M to R Matching
Authors: Ejigou Ayenew
Published: May 2007

Estimation of the relative risk from a rare disease is carried out using M:R matching. Both conditional and unconditional likelihood methods are used, leading in each case to the same estimate; a non‐iterative estimate is always available under M:R matching, M ≦2. The method also enables the testing of homogeneity even when information on the matching variate is unavailable and this is an advantage over logistic regression methods.
An Example of Simultaneous Multivariate Linear Modelling of Among and Within Subject Variation
Authors: Singer J. M. , Koch G. G. , Stinnett S. S. , Warren D. W.
Published: May 2007

An example of simultaneous linear modelling of among and within subject variation through weighted least squares methods is presented as an alternative to standard multivariate analysis of variance techniques. The data pertain to a study of temporal characteristics of some aerodynamic parameters from a speech test used to differentiate groups of individuals with different degrees of palatopharyngeal closure. Both methods are found to yield similar results with respect to the among group comparisons, but the simultaneous strategy enables some further reduction in dimensionality, and thereby extends the description of patterns in the data.
Statistical Comment on a New Method for Noncompartmental Pharmacokinetic Analysis
Authors: Van Linde A. Der
Published: May 2007

A new method for parameter estimation and calculation of moments of concentration‐time curves recently introduced by H. Knolle is reviewed from a statistical point of view.
Robust continuous collision detection for interactive deformable surfaces
Authors: Wong Wingo Sai‐Keung , Baciu George
Published: May 2007

Collision events between 3D objects in motion in computer animations or simulations are difficult to detect due to the difficulty of accurately sampling the motion paths of objects in space and time. One approach to this problem has been continuous collision detection but because the current approaches process potentially interacting primitive pairs (PIPPs) redundantly. This is time‐expensive, especially where there are a large number of PIPPs. In this paper we propose a novel collision detection process that more accurately and robustly detects collisions on simulated meshed deformable surfaces. We embed a new layer, primitive filtering layer (PFL), to extract PIPPs. This has two results. It reduces the number of PIPPs significantly and it means that each interacting primitive pair is processed just one time. Experimental results show that this approach achieves interactive rates for complex deformable surfaces with large contact regions. This is especially practical for cloth dynamics. Our method is efficient, accurate, reliable, and robust even in the presence of objects with sharp features. We also present techniques to implement the method on programmable graphics processing units (GPUs). Copyright © 2007 John Wiley & Sons, Ltd.
Age disparity between a cancer population and participants in clinical trials submitted as a new drug application of anticancer drugs in Japan
Authors: Hori Akiko , Shibata Taro , Kami Masahiro , Kusumi Eiji , Narimatsu Hiroto , Kishi Yukiko , Murashige Naoko , Mori Kazuhiko
Published: May 2007

BACKGROUND.

Underrepresentation of older patients in cancer clinical trials has been reported previously.

METHODS.

To evaluate disparities in age between actual cancer patients and those enrolled in clinical trials, the authors examined all the review reports of the Pharmaceuticals and Medical Devices Agency, Tokyo, Japan, and summaries of data submitted by applicants for the approval of new cancer drugs and that of a partial change in approved cancer drugs.

RESULTS.

Information regarding 68 clinical trials was available on the Internet. The median age of trial participants ranged from 33 years to 73 years and was older than 65 years in 13 trials, whereas the estimated median age of patients with all cancers was 69 years, and 64% of these individuals were age ≥65 years. The median age of trial participants was found to be lower than that of the patient population in 60 trials. The median difference in age between the 2 groups was 7 years (range, −16 to +33). With regard to molecular‐targeting agents (16 trials) and hormonal agents (10 trials), trial participants were younger than the patient population in 25 of the 26 trials, with a median difference of 6 years (range, −9.5 to +20). The difference was larger for molecular‐targeting agents (median, 9.5 years; range, birth‐20 years) compared with hormonal agents (median, 2 years; range, −9.5 to +15).

CONCLUSIONS.

The results of the current study show that participants in cancer clinical trials are younger than the actual Japanese cancer patient population. Cancer 2007. © 2007 American Cancer Society.
Fast transimpedance switching burst‐mode CMOS optical receiver
Authors: Schneider Kerstin , Zimmermann Horst
Published: May 2007

This work shows that the performance of optical receivers designed in silicon deep‐sub‐micron CMOS technologies competes successfully with more expensive SiGe‐BiCMOS receivers in data rate and sensitivity. In burst‐mode applications of passive optical networks, the transimpedance of the low‐noise amplifier has to be switched very fast requiring, the exclusion of oscillations. To meet the burst‐mode requirements, our design for 2.5 G bit/s in 120 nm CMOS offers a fast switching of the transimpedance within 3 ns and proves a low‐distortion signal detection. Copyright © 2007 John Wiley & Sons, Ltd.
Ablation of de novo DNA methyltransferase Dnmt3a in the nervous system leads to neuromuscular defects and shortened lifespan
Authors: Nguyen Suzanne , Meletis Konstantinos , Fu Dongdong , Jhaveri Sonal , Jaenisch Rudolf
Published: May 2007

DNA methylation is an epigenetic mechanism involved in gene regulation and implicated in the functioning of the nervous system. The de novo DNA methyltransferase Dnmt3a is expressed in neurons, but its specific role has not been clarified. Dnmt3a is activated around embryonic day 10.5 in mouse neuronal precursor cells and remains active in postmitotic neurons in the adult. We assessed the role of neuronal Dnmt3a by conditional gene targeting. Mice lacking functional Dnmt3a in the nervous system were born healthy, but degenerated in adulthood and died prematurely. Mutant mice were hypoactive, walked abnormally, and underperformed on tests of neuromuscular function and motor coordination. Loss of Dnmt3a also led to fewer motor neurons in the hypoglossal nucleus and more fragmented endplates in neuromuscular junctions of the diaphragm muscle. Our results implicate a role for Dnmt3a in the neuromuscular control of motor movement. Developmental Dynamics 236:1663–1676, 2007. © 2007 Wiley‐Liss, Inc.
Evolutionary perspectives from development of mesodermal components in the lamprey
Authors: Kusakabe Rie , Kuratani Shigeru
Published: May 2007

Lampreys, a jawless vertebrate species, lack not only jaws but also several other organs, including ventral migratory muscles shared by gnathostomes. In the lamprey embryo, the mesoderm consists primarily of unsegmented head mesoderm, segmented somites, and yet uncharacterized lateral plate mesoderm, as in gnathostomes. Although the adult lamprey possesses segmented myotomes in the head, the head mesoderm of this animal is primarily unsegmented, similar to that in gnathostomes. In the trunk, the large part of lamprey somites is destined to form myotomes, and the Pax3/7 gene expression domain in the lateral part of somites is suggested to represent a dermomyotome homologue. Lamprey myotomes are not segregated by a horizontal myoseptum, which has been regarded as consistent with the apparent absence of a migratory population of hypaxial muscles shared by gnathostomes. However, recent analysis suggests that lampreys have established the gene regulatory cascade necessary for the ventrally migrating myoblasts, which functions in part during the development of the primordial hypobranchial muscle. There have also been new insights on the developmental cascade of lamprey cartilages, in which the Sox family of transcription factors plays major roles, as in gnathostomes. Thus, mesoderm development in lampreys may represent the ancestral state of gene regulatory mechanisms required for the evolution of the complex and diverse body plan of gnathostomes. Developmental Dynamics 236:2410–2420, 2007. © 2007 Wiley‐Liss, Inc.
DNA Interactions Mediated by Cyclopentadienidoruthenium(II) Complexes Containing Water‐Soluble Phosphanes
Authors: Romerosa Antonio , Saoud Mustapha , Campos‐Malpartida Tatiana , Lidrissi Chaker , Serrano‐Ruiz Manuel , Peruzzini Maurizio , Garrido Jose Antonio , García‐Maroto Federico
Published: May 2007

The water‐soluble ruthenium(II) complexes Na2[RuCpX(mTPPMS)2] [X = Cl (1), I (2)] and Nax[RuCp(mTPPMS)(PR13)(PR23)](OTf)y [PR13 = PR23 = PPh3 (3), PTA (4), x = y = 0; PR13 = mTPPMS, PR23 = PTA (5), x = 1, y = 0; PR13 = mTPPMS, PR23 = mPTA (6), x = y = 0; PR13 = PR23 = mTPPMS (7), x = 2, y = 0; PR13 = PPh3, PR23 = PTA (8), x = y = 0; PR13 = mPTA, PR23 = PPh3 (9), x = 0, y = 1; mTPPMS = Ph2P(3‐OSO2C6H4)–; PTA = 1,3,5‐triaza‐7‐phosphaadamantane; mPTA = N‐methyl‐1,3,5‐triaza‐7‐phosphaadamantane] have been synthesized and characterised by elemental analysis, NMR and IR spectroscopy and crystallographic methods. The X‐ray crystal structure determination of [RuCp(mTPPMS)(PPh3)(PTA)]·2H2O (8·2H2O), which is the first half‐sandwich ruthenium complex bearing three different phosphanes, has also been determined. The binding properties of these new water‐soluble ruthenium complexes towards DNA and the interaction of free mTPPMS with the nucleic acid have been studied using the mobility shift assay, which has shown that both the activity of the ruthenium complexes and the possible mechanism governing the interaction with DNA are strictly dependent on the composition of the complexes.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Functionalization of Vinylspherosilicates by Ruthenium‐Catalyzed Silylative Coupling Reactions
Authors: Waehner Jacek , Marciniec Bogdan , Pawluć Piotr
Published: May 2007

Highly effective functionalization of monovinylsiloxy heptaisobutylsilsesquioxane and octavinylspherosilicate of the formula (ViMe2SiO)(iBu)7Si8O12 (1) and (ViMe2SiO)8Si8O12 (2), respectively, with a variety of olefins, by using a Ru(H)(Cl)(CO)(PCy3)2‐catalyzed silylative coupling procedure is reported. The cross‐metathesis reaction catalyzed by a ruthenium–carbene complex does not proceed for this system. Whereas the reaction of 1 and 2 with styrene takes place highly stereo‐ and regioselectively, the respective reaction with 1‐hexene gives a mixture of isomers. However, functionalization of 1 and 2 with vinylic heteroatom‐substituted (N, O, Si) derivatives was found to be highly efficient for the synthesis of spherosilicates with β‐heteroatom vinylic functionalities (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Preparation and Molecular Structures of Stable Bis(germylenes) with Pincer Topology
Authors: Hahn F. Ekkehardt , Zabula Alexander V. , Pape Tania , Hepp Alexander
Published: May 2007

Benzannulated N‐heterocyclic bis(germylenes) with pincer ligand topology have been prepared by the reaction of N,N′,N″,N″′‐tetralithiated tetraamines with GeCl2·1,4‐dioxane or by the transamination reaction between a tetraamine and Ge[N(SiMe3)2]2. X‐ray diffraction studies have shown, that the bis(germylenes) exist as monomers in the solid state. Significant intramolecular Ge···Ge and Ge···N interactions have been observed for the lutidine‐bridged bis(germylene). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
System‐justifying ideologies moderate status = competence stereotypes: roles for belief in a just world and social dominance orientation
Authors: Oldmeadow Julian , Fiske Susan T.
Published: May 2007

High‐status outgroups tend to be stereotyped as competent, while low‐status groups tend to be stereotyped as incompetent. These stereotypes provide legitimacy to hierarchical social systems. However, research to date has tended to focus on the socio‐structural correlates and cross‐cultural stability of these stereotypes, emphasising universality over malleability. The current research demonstrates that, although strong, the association between status and competence, but not status and warmth, is moderated by ideological beliefs and attitudes towards inequality. In two studies, participants high in belief in a just world (BJW) or social dominance orientation (SDO) were more likely than those low in BJW or SDO to view a high‐status target as more competent than a low‐status target. Findings support the view that status stereotypes justify social inequalities, and demonstrate that they are sensitive to ideological orientations. Implications for theory and research on status and power stereotypes are discussed. Copyright © 2007 John Wiley & Sons, Ltd.
Universal method for synthesis of artificial gel antibodies by the imprinting approach combined with a unique electrophoresis technique for detection of minute structural differences of proteins, viruses and cells (bacteria). Ib. Gel antibodies against proteins (hemoglobins)
Authors: Takátsy Anikó , Végvári Ákos , Hjertén Stellan , Kilár Ferenc
Published: May 2007

Using the molecular imprinting approach, we have shown that polyacrylamide‐based artificial antibodies against human and bovine hemoglobin have a very high selectivity, as revealed by the free‐zone electrophoresis in a revolving capillary. By the same technique we have previously synthesized gel antibodies not only against proteins but also against viruses and bacteria. The synthesis is thus universal, i.e., it has the great advantage of not requiring a modification – or only a slight one – for each particular antigen. The combination synthesis of artificial gel antibodies and electrophoretic analysis reveals small discrepancies in shape and chemical composition not only of proteins, as shown here and in paper Ia, but also of viruses and bacteria, to be illustrated in papers II and III in this series. Upon rehydration, the freeze‐dried gel antibodies, selective for human hemoglobin, regain their selectivity. The gel antibodies can repeatedly be used following the removal of the antigen (protein in this study) from the complex gel antibody/antigen by an SDS washing or an enzymatic degradation.
CEC separation of insect oostatic peptides using a strong‐cation‐exchange stationary phase
Authors: Rocco Anna , Aturki Zeineb , D'Orazio Giovanni , Fanali Salvatore , Šolínová Veronika , Hlaváček Jan , Kašička Václav
Published: May 2007

The separation of several insect oostatic peptides (IOPs) was achieved by using CEC with a strong‐cation‐exchange (SCX) stationary phase in the fused‐silica capillary column of 75 μm id. The effect of organic modifier, ionic strength, buffer pH, applied voltage, and temperature on peptides' resolution was evaluated. Baseline separation of the studied IOPs was achieved using a mobile phase containing 100 mM pH 2.3 sodium phosphate buffer/water/ACN (10:20:70 v/v/v). In order to reduce the analysis time, experiments were performed in the short side mode where the stationary phase was packed for 7 cm only. The selection of the experimental parameters strongly influenced the retention time, resolution, and retention factor. An acidic pH was selected in order to positively charge the analyzed peptides, the pI's of which are about 3 in water buffer solutions. A good selectivity and resolution was achieved at pH <2.8; at higher pH the three parameters decreased due to reduced or even zero charge of peptides. The increase in the ionic strength of the buffer present in the mobile phase caused a decrease in retention factor for all the studied compounds due to the decreased interaction between analytes and stationary phase. Raising the ACN concentration in the mobile phase in the range 40–80% v/v caused an increase in both retention factor, retention time, and resolution due to the hydrophilic interactions of IOPs with free silanols and sulfonic groups of the stationary phase.
Viscous dissipative fluid flow past a semi‐infinite vertical plate with variable surface temperature
Authors: Palani G.
Published: May 2007

An analysis of the effect of viscous dissipative heat on two‐dimensional viscous incompressible fluid flow past a semi‐infinite vertical plate with variable surface temperature is carried out. The dimensionless governing equations are unsteady, two‐dimensional, coupled, and non‐linear governing equations. A most accurate, unconditionally stable and fast converging implicit finite‐difference scheme is used to solve the non‐dimensional governing equations. Velocity and temperature of the flow have been presented graphically for various parameters occurring in the problem. The local and average skin friction and Nusselt number are also shown graphically. It is observed that greater viscous dissipative heat causes a rise in the temperature. Copyright © 2007 John Wiley & Sons, Ltd.
Unawareness of motor impairment and emotions in right hemispheric stroke: a preliminary investigation
Authors: Spalletta Gianfranco , Serra Laura , Fadda Lucia , Ripa Alessandra , Bria Pietro , Caltagirone Carlo
Published: May 2007

Background

Awareness may lack in some stroke patients who are not capable of evaluating the nature and severity of illness. Thus, unawareness may have different forms such as anosognosia, neglect, and alexithymia or unawareness of emotions. In this study we investigated the relationship among anosognosia, neglect, alexithymia, and cognition.

Methods

Fifty consecutive right stroke inpatients were approached within the first 3 months from the acute event. Anosognosia was measured with the Bisiach scale, alexithymia with the TAS‐20 scale and neglect with line crossing, letter cancellation, figure and shape copying, and line bisection tests. A neuropsychological test battery was used to measure different areas of cognition.

Results

despite the strong comorbidity rate among the different forms of unawareness, there are patients who suffer from pure forms of these types of lack of awareness. A multivariate logistic regression model evidenced that presence of neglect (OR = 10.3; 95% CI = 1.4–76.3; p = 0.023) and more difficulty in describing feelings (TAS‐20 F2 subscore; OR = 1.3; 95% CI = 1.1–1.7; p = 0.014) were the only predictors of anosognosia. In addition, anosognosics with alexithymia performed worst in a frontal task such as the verbal fluency task (p = 0.042) and in the verbal span forward task (p = 0.026) than pure anosognosics.

Conclusions

Anosognosia for motor impairment is strictly associated with a specific form of unawareness of emotions. Future studies have to clarify if frontal cognitive impairment previously described in anosognosics is a manifestation of unawareness of emotions or anosognosia for motor impairment. Copyright © 2007 John Wiley & Sons, Ltd.
Construction of a combinatorial library of 2‐(4‐oxo‐4H‐1‐benzopyran‐3‐yl)‐4‐thiazolidinones by microwave‐assisted one‐pot parallel syntheses
Authors: Zhou Zhong‐Zheng , Huang Wei , Ji Feng‐Qin , Ding Ming‐Wu , Yang Guang‐Fu
Published: May 2007

A one‐pot liquid‐phase combinatorial synthesis of 2‐(4‐oxo‐4H‐1‐benzopyran‐3‐yl)‐4‐thiazolidinones bearing diverse substituents at the 3‐position under microwave irradiation was successfully performed using 3‐formyl chromone, primary amine, and mercaptoacetic acid as reactants. Compared to an identical library generated by conventional parallel synthesis, the microwave‐assisted parallel synthesis approach dramatically decreased the reaction time from an average of 9 h to 5 min, and substantially increased the product yields. The coupling of microwave technology with liquid‐phase combinatorial synthesis constitutes a novel and particularly attractive avenue for the rapid generation of structurally diverse libraries. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:381–389, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20309
Synthesis and antimicrobial activity of new functionalized derivatives of [1,2,4]triazolo[4,3‐a]pyrimidin‐5(1H)‐one
Authors: Shawali Ahmad S. , Mahran Asma M. , Nada Afaf A.
Published: May 2007

New functionalized 1,7‐diaryl‐6‐cyano‐1,2,4‐triazolo[4,3‐a]pyrimidin‐5(1H)‐one derivatives (5a–j) were synthesized via reaction of 5‐cyano‐6‐phenyl‐2‐thiouracil1with the respective hydrazonoyl halides2a–jand their biological activity was evaluated. The mechanism and the regioselectivity of the studied reactions are discussed. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:393–398, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20311
Reactions with dimethylformamide‐dimethylacetal: Synthesis and reactions of several new pyridine and pyrazolo[3,4‐b]pyridine derivatives
Authors: Elneairy Mohamed A. A. , Gad‐Elkareem Mohamed A. M. , Taha Adel M.
Published: May 2007

6‐Aminopyridine‐2(1H)‐thiones 1a,b reacted with dimethylformamide‐dimethylacetal (DMF‐DMA) to give the corresponding 6‐{[(N,N‐dimethylamino)methylene]amino}pyridine derivatives 2a,b. The latter compounds reacted with hydrazine hydrate to afford the 3,6‐diamino‐1H‐pyrazolo[3,4‐b]pyridine derivative 4 and 3‐amino‐5‐hydrazino‐1H‐pyrazolo[4′,3′:5,6]pyrido[2,3‐d]pyrimidine derivative 7, respectively. Compound 4 condensed with DMF‐DMA to yield the 3,6‐bis{[(N,N‐dimethylamino)methylene]amino}‐1H‐pyrazolo[3,4‐b]pyridine derivative 10, which reacted with malononitrile to give the corresponding pyridopyrazolopyrimidine derivative 15. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:399–404, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20312
Modification of styrene polymer with organosilicon groups
Authors: Assadi M. G. , Mahkam M. , Tajrezaiy Z.
Published: May 2007

The homopolymer of 4‐chloromethylstyrene (P1) and its copolymers with styrene (in various mole ratios) were synthesized by bulk and solution free radical polymerizations, respectively, at 70 ± 1°C using α,α′‐azobis(isobutyronitrile) as an initiator. Lithiation of these soluble polymers in THF at −78°C was done and reacted with electrophiles such as tert‐BuMe2Si, Et3Si, and Me3SiCH2 in the presence of 4,4′‐di‐tert‐butylbiphenyl (DTBB) as a catalyst to produce modified polystyrene. In the other way, trimethylsilylmethyl lithium substitute as a nucleophile was covalently linked to the homopolymer and copolymer. The polymers were characterized by IR, 1H NMR, 13C NMR, differential scanning calorimetry (DSC), and gel permeation chromatography. DSC showed that incorporation of silyl substitute in the side chains of homopolymer and copolymers increases the rigidity of the polymers and, subsequently, their glass transition temperature. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:414–420, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20314
Original recyclization of S‐phenacyl derivatives of 4‐acylamino‐2‐mercapto‐1,3‐oxazoles and their analogues
Authors: Balia Andrei G. , Belyuga Aleksandr G. , Brovarets Vladimir S. , Vasylenko Aleksandr N. , Turov Aleksandr V. , Gakh Andrei A. , Drach Boris S.
Published: May 2007

Readily accessible acylamino(chloro)acetophenones, if treated with sodium rhodanide and α‐halogenocarbonyl compounds, provide 4‐acylamino‐5‐aryl‐2‐mercapto‐1,3‐oxazole derivatives which undergo recyclization on heating in polyphosphoric acid to give substituted 1,3‐thiazol‐2(3H)‐ones or 1,3‐thiazolidin‐2,4‐diones containing 2‐alkyl(aryl)‐5‐aryl‐1,3‐oxazol‐4‐yl residues at the N3 atom. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:432–437, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20317
Synthesis of phenoxy‐substituted spiro‐ansa phosphazene derivatives
Authors: Begeç Saliha
Published: May 2007

In this study, reactions of 2,4,4,6,6‐pentachloro‐2‐(2,4,6‐trimethylphenoxy)cyclo‐2λ5,4λ5,6λ5‐triphosphazatriene (1) and 2,4,4,6,6‐pentachloro‐2‐(2,4,6‐tritertbutylphenoxy)cyclo‐2λ5,4λ5,6λ5‐triphosphazatriene (2) with 2,2′‐dihydroxybiphenyl (3) in acetone in the presence of potassium carbonate have been investigated. Mono ansa (4) and spiro‐ansa (5) derivatives were obtained from of 3 with 1, while mono spiro (6) and mono ansa (7) derivatives were obtained from 2. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:372–375, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20322
Human neutrophil elastase and collagenase sequestration with phosphorylated cotton wound dressings
Authors: Edwards J. Vincent , Howley Phyllis S.
Published: May 2007

The design and preparation of wound dressings that redress the protease imbalance in chronic wounds is an important goal of wound healing and medical materials science. Chronic wounds contain high levels of tissue and cytokine‐destroying proteases including matrix metalloprotease and neutrophil elastase. Thus, the lowering of excessive protease levels in the wound environment by wound dressing sequestration prevents the breakdown of extracellular matrix proteins and growth factors necessary for wound healing. Phosphorylated cotton wound dressings were prepared to target sequestration of proteases from chronic wound exudate through a cationic uptake binding mechanism involving salt bridge formation of the positively charged amino acid side chains of proteases with the phosphate counterions of the wound dressing fiber. Dressings were prepared by applying sodium hexametaphosphate and diammonium phosphate in separate formulations to cotton gauze by pad/dry/cure methods. Phosphorylated cotton dressings were assessed for their ability to lower elastase and collagenase activity. The phosphorylated cotton dressings lowered elastase and collagenase activity 40–80% more effectively than the untreated cotton wound dressings under conditions that mimic chronic wound exudate. Efficacy of the phosphorylated cotton was found to be related to the level of phosphorylation and a lower pH due to protonated phosphate at the surface of the dressing. The capacity of the modified gauze to sequester continued elastase secretions similar to that found in a chronic wound over a 24‐h period was retained within a 80% retention of elastase sequestration and was dose‐dependent. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2007