bluuebunny/crossref_metadata_2025_split huggingface dataset:
Angulated femurs and the skeletal dysplasias: Experience of the International Skeletal Dysplasia Registry (1988–2006)
Authors: Alanay Yasemin , Krakow Deborah , Rimoin David L. , Lachman Ralph S. 
Published: May 2007

AbstractAngulated or bent femur (isolated or associated with other long bone bowing) in the fetus or newborn is relatively common when evaluating patients with skeletal dysplasias. To determine the extent and heterogeneity of disorders associated with angulated or bent femurs, we analyzed cases in the radiographic database (1998–2006) of the International Skeletal Dysplasia Registry (ISDR) and determined which established skeletal dysplasias and genetic syndromes are associated with this finding. The results show that more than 40 distinct disorders with varying frequency (very rare to more commonly occuring disorders) can be associated with bowed/bent/angulated femurs. Sixty‐six percent of the cases with angulated femurs belonged to three well described groups of disorders; campomelic disorders (24.4%), thanatophoric dysplasia (23.9%) and osteogenesis imperfecta (OI) (18.1%). With specific emphasis on these, this cross‐sectional cohort provides discussion of data on other rare disorders associated with angulated femurs and the importance of the finding relative to its occurrence within a diagnostic group. This study aims to provide differential diagnosis of entities to be considered when a fetus or newborn is found to have congenital bowing/angulation of the femur. © 2007 Wiley‐Liss, Inc.
Microcephaly with chorioretinopathy in a brother–sister pair: Evidence for germ line mosaicism and further delineation of the ocular phenotype
Authors: Trzupek Karmen M. , Falk Rena E. , Demer Joseph L. , Weleber Richard G. 
Published: May 2007

AbstractMicrocephaly with chorioretinopathy (OMIM 156590) is an autosomal dominant syndrome, characterized primarily by chorioretinal lesions and microcephaly. The phenotype is variable, and has been described in association with retinal dysplasia that can be stable or show progressive degeneration, retinal folds, lymphedema, and mental retardation. We describe two siblings with microcephaly, mental retardation, and variable retinal and choroidal abnormalities. Patient 1 has multiple atrophic and dysplastic‐appearing lesions of the retina and choroid in each eye. An ERG at 5 months of age disclosed markedly subnormal scotopic and photopic responses with delayed flicker timing. Patient 2 has bilateral macular folds with vitreoretinopathy, serous retinal detachments, glaucoma, and cataracts OU. Both have mental retardation with hypotonia and severe microcephaly. Chorioretinopathy and retinal folds have been described independently in microcephaly with chorioretinopathy. The present sibs are the first in whom these features are observed while the parents are normal. Our findings support an expansion of the ocular phenotype and suggest the existence of germ line mosaicism. © 2007 Wiley‐Liss, Inc.
Recurrent interstitial deletions of proximal 18q: A new syndrome involving expressive speech delay
Authors: Cody Jannine D. , Sebold Courtney , Malik Amtul , Heard Patricia , Carter Erika , Crandall AnaLisa , Soileau Bridgette , Semrud‐Clikeman Margaret , Cody Catherine M. , Hardies L. Jean , Li Jinqi , Lancaster Jack , Fox Peter T. , Stratton Robert F. , Perry Brian , Hale Daniel E. 
Published: May 2007

AbstractMost deletions of the long arm of chromosome 18 involve some part of the most distal 30 Mb. We have identified five individuals with cytogenetically diagnosed interstitial deletions that are all proximal to this commonly deleted region. The extent of their deletions was characterized using molecular and molecular cytogenetic techniques. Each participant was assessed under the comprehensive clinical evaluation protocol of the Chromosome 18 Clinical Research Center. Three of the five individuals were found to have apparently identical interstitial deletions between positions of 37.5 and 42.5 Mb (18q12.3 → 18q21.1). One individual's deletion was much larger and extended from a more proximal breakpoint position of 23 Mb (18q11.2) to a more distal breakpoint at 43 Mb (18q21.1). The fifth individual had a proximal breakpoint identical to the other three, but a distal breakpoint at 43.5 Mb (18q21.1). The clinical findings were of interest because the three individuals with the smaller deletions lacked major anomalies. All five individuals were developmentally delayed; however, the discrepancy between their expressive and receptive language abilities was striking, with expressive language being much more severely affected. This leads us to hypothesize that there are genes in this region of chromosome 18 that are specific to the neural and motor planning domains necessary for speech. Additionally, this may represent a previously underappreciated syndrome since these children do not have the typical clinical abnormalities that would lead to a chromosome analysis. © 2007 Wiley‐Liss, Inc.
Absence of PITX2, BARX1, and FOXC1 mutations in De Hauwere syndrome (Axenfeld–Rieger anomaly, hydrocephaly, hearing loss): A 25‐year follow up
Authors: Lowry R. Brian , Gould Douglas B. , Walter Michael A. , Savage Paul R. 
Published: May 2007

AbstractThis study reports a 25‐year follow‐up of a patient with De Hauwere syndrome (Axenfeld–Rieger anomaly, hydrocephalus, and hearing loss) whose intelligence is normal. Short stature and hyperlaxity of joints later leading to severe joint pain were noted. Mutation analysis of candidate genes known or suspected to be associated with Axenfeld–Rieger eye malformations was performed. This included complete sequencing for PITX2, BARX1 and the forkhead domain of FOXC1. The results of these analyses were negative and suggest that De Hauwere syndrome is caused by a different gene. © 2007 Wiley‐Liss, Inc.
Report of a fourth individual with a lethal syndrome of choanal atresia, athelia, evidence of renal tubulopathy, and family history of neck cysts
Authors: Horvath Gabriella A. , Armstrong Linlea 
Published: May 2007

AbstractIn 1998, Hisama et al. described three brothers born following pregnancies complicated by oligohydramnios in the second or third trimester. Post‐natal renal functions were compromised, and post‐mortem studies showed kidney tissue abnormalities. Resuscitation and support were required, and they survived 25 hr to 12 days. All boys had a similar craniofacial appearance with infraorbital creases, low set dysplastic ears, as well as athelia, and broad digits with small nails. Variably present features were choanal atresia, preauricular tags and pits, branchial clefts, ventricular septal defect, type IIB interrupted aortic arch, pulmonary lobation anomaly, absent gallbladder, absent thymus, absent parathyroid gland, accessory spleen, and imperforate anus. Their mother, maternal grandmother, and maternal first cousin had neck cysts removed as children. We describe a female infant born following a pregnancy where oligohydramnios developed between 27 and 33 weeks gestation. Renal function was initially impaired, but improved over the first weeks of life. There was however a persistent renal wasting of magnesium. Her craniofacial appearance with infraorbital creases and low set dysplastic ears was similar to the brothers' described by Hisama et al. [1998; Am J Med Genet 80:335–342]. She had choanal atresia, athelia, a preauricular pit, gingival cysts, broad digits with small nails, right aortic arch with a vascular ring, hypothyroidism, impaired glucose homeostasis, hypoadrenalism, neurological impairment, and brain calcifications on CT. She died after 13 weeks of intensive care. Her mother as a child and maternal grandfather as an adult had neck cysts removed. The similarities between the cases suggest a common syndrome. © 2007 Wiley‐Liss, Inc.
Inbreeding depression in non‐human primates: a historical review of methods used and empirical data
Authors: Charpentier M.J.E. , Widdig A. , Alberts S.C. 
Published: May 2007

AbstractOffspring born to related parents may show reduced fitness due to inbreeding depression. Although evidence of inbreeding depression has accumulated for a variety of taxa during the past two decades, such analyses remain rare for primate species, probably because of their long generation time. However, inbreeding can have important fitness costs and is likely to shape life‐history traits in all living species. As a consequence, selection should have favored inbreeding avoidance via sex‐biased dispersal, extra‐group paternity, or kin discrimination. In this paper, we review empirical studies on the effects of inbreeding on fitness traits or fitness correlates in primate species. In addition, we report the methods that have been used to detect inbreeding in primate populations, and their development with the improvement of laboratory techniques. We focus particularly on the advantages and disadvantages using microsatellite loci to detect inbreeding. Although the genetic data that are typically available (partial pedigrees, use of microsatellite heterozygosity as an estimate of genomewide inbreeding) tend to impose constraints on analyses, we encourage primatologists to explore the potential effects of inbreeding if they have access to even partial pedigrees or genetic information. Such studies are important because of both the value of basic research in inbreeding depression in the wild and the conservation issues associated with inbreeding, particularly in threatened species, which include more than half of the currently living primate species. Am. J. Primatol. 69:1370–1386, 2007. © 2007 Wiley‐Liss, Inc.
The effects of RF absorbers on exposure levels at 100 MHz
Authors: Allen Stewart J , Mylacraine Kevin S. 
Published: May 2007

AbstractThe study presented in this article was designed to complete a dosimetry protocol required to establish the RF exposure levels at 100 MHz for measurement of the effect on cognition in human volunteers near the resonant frequency in seated positions. The results are compared with those reported previously using the same experimental procedures, except with the vertically radiating dipole antenna and corner reflector raised by .30 m to the vertical center of the anechoic chamber. The average whole body SAR for the high and low SAR conditions used in the previous study was achieved with a 12% increase in transmitter forward power. However, the incident power density averaged over the body was increased by 42%, from 40 and 80 W/m2 in the previous study to 57 and 113 W/m2 in the current study to achieve the same whole body average SAR used in the previous study. The differences in field patterns and field intensities between the previous and current studies were introduced by interactions between the E‐field and RF absorbers in the floor and ceiling, which represent resonant structures at 100 MHz. Bioelectromagnetics 28:406–408, 2007. © 2007 Wiley‐Liss, Inc.
Assessing the numerical accuracy of the impedance method
Authors: Olree Kenneth S. , Horch Kenneth W. 
Published: May 2007

AbstractThe impedance method has been used extensively to calculate induced electric fields and currents in tissue as a result of applied electromagnetic fields. However, there has previously been no known method for an a priori assessment of the numerical accuracy of the results found by this method. Here, we present a method which permits an a priori assessment of the numerical accuracy of the impedance method applied to physiologically meaningful problems in bioengineering. The assessment method relies on estimating the condition number associated with the impedance matrix for problems with varying shapes, sizes, conductivities, anisotropies, and implementation strategies. Equations have been provided which predict the number of significant figures lost due to poor matrix conditioning as a function of these variables. The results show that, for problems of moderate size and uncomplicated geometry, applied fields should be measured or calculated accurately to at least five or six significant figures. As resolutions are increased and material properties are more widely divergent even more significant figures are needed. The equations provided here should ensure that solutions found from the impedance method are calculated accurately. Bioelectromagnetics 28:454–462, 2007. © 2007 Wiley‐Liss, Inc.
Does direction of induced electric field or current provide a test of mechanism involved in nerve regeneration?
Authors: Greenebaum B. , Sisken Betty F. 
Published: May 2007

AbstractWe suggest an experimental comparison of two directions for applying the time‐varying magnetic fields which have been found to speed spontaneous regeneration of injured peripheral nerves and in attempts to repair spinal cord injuries. Time‐varying magnetic fields induce currents in a plane perpendicular to the magnetic field direction. The lower conductivity of the spinal cord's sheath (dura matter) or of the myelin sheath of peripheral nerves would seem to confine the induced electric fields and currents to the spinal cord or nerve itself. The proposed comparison could allow choosing between two possible modes of action of the fields: (1) Magnetically‐induced electric fields or currents may be encouraging ion flow or otherwise helping enzyme, channel or other interactions at the cell membrane, as is thought to be the case in field stimulation of healing in bone. This mechanism should be independent of field direction. (2) Work in developing organisms and with fields applied to nerve cells in vitro has shown that neurite growth is guided parallel to both endogenous and external electric fields. This mechanism would be effective when induced electric fields are parallel, but not when they are perpendicular to the nerve. Any experimental test should seek to produce as close as possible to the same induced current intensity with both field directions. Possible confounding factors, as well as breakdowns in the assumptions of the simple model presented here, would have to be considered. This proposal was motivated by a recent report in which the authors listed a changed field direction as one of several possible reasons for an unsuccessful experiment. Bioelectromagnetics 28:488–492, 2007. © 2007 Wiley‐Liss, Inc.
Dominant factors influencing whole‐body average SAR due to far‐field exposure in whole‐body resonance frequency and GHz regions
Authors: Hirata Akimasa , Kodera Sachiko , Wang Jianqing , Fujiwara Osamu 
Published: May 2007

AbstractElectromagnetic (EM) absorption of the human body for far‐field exposure at the International Commission on Non‐Ionizing Radiation Protection (ICNIRP) reference level has two peaks in the resonance frequency and GHz regions. Dominant factors influencing whole‐body average specific absorption rate (SAR) in these two frequency regions have not yet been revealed sufficiently. The main purpose of this study is to clarify the dominant factors influencing EM power absorption in terms of whole‐body average SAR in an anatomically based model compared with those in a homogeneous anthropomorphic model and corresponding cuboid models. Computational results show that EM absorption peak in the resonance frequency region greatly depends on the electric properties of tissue, while the peak in the GHz region is affected mainly by the surface area of the model. Bioelectromagnetics 28:484–487, 2007. © 2007 Wiley‐Liss, Inc.
Efficiency of a Two‐Stage Procedure for Survival Studies
Authors: Flandre Philippe 
Published: May 2007

AbstractA two‐stage procedure using occurrences of a surrogate endpoint regarding a true clinical endpoint has been proposed (FLANDRE, O'QUIGLEY and BROOKMEYER, 1994). The procedure allows estimation of the survival function S(t) reliably and comparison of treatment groups. The aim of this paper is to investigate the efficiency of such a two‐stage procedure compared to a one stage procedure, i.e. a classical study. The efficiency is estimated by the ratio of the standard derivation of S(t) for the classical procedure to the standard derivation of S(t) for the two‐stage procedure and represents the precision on the estimation of S(t). Standard deviation of S(t) is approximate by the delta‐method. Using the exponential model. some numerical results are presented.
Confidence Intervals on Linear Combinations of K Variances
Authors: Anbupalam T. , Ponnuswamy K. N. , Srinivasan M. R. 
Published: May 2007

AbstractTING et al. (1990) have proposed a method of constructing approximate confidence intervals on linear combinations of several variances that are unrestricted in sign. In this article we have proposed modifications of their method. The performances of the proposed modifications are examined using a computer simulation.
A Nonparametrical Evaluation of Anova and MANOVA Designs Using Interaction Structure Analysis
Authors: Stemmler Mark 
Published: May 2007

AbstractThe interaction structure analysis (ISA) is proposed as a nonparametric procedure for the evaluation of uni‐ and multivariate analysis of variance models. Main effects and interactions of (independent) treatment variables are replaced by interaction‐types where types are defined as those treatment‐response combinations which occur significantly more often than expected under a null hypothesis (Ho) of no treatment effects. The application of ISA and the typological interpretation of ISA results are illustrated for an ANOVA design from toxicology and for a MANOVA design from psychopharmacology.
Biplots in Reduced‐Rank Regression
Authors: Braak Cajo J. F. Ter , Looman Caspar W. N. 
Published: May 2007

AbstractRegression problems with a number of related response variables are typically analyzed by separate multiple regressions. This paper shows how these regressions can be visualized jointly in a biplot based on reduced‐rank regression. Reduced‐rank regression combines multiple regression and principal components analysis and can therefore be carried out with standard statistical packages. The proposed biplot highlights the major aspects of the regressions by displaying the least‐squares approximation of fitted values, regression coefficients and associatedt‐ratios. The utility and interpretation of the reduced‐rank regression biplot is demonstrated with an example using public health data that were previously analyzed by separate multiple regressions.
Evaluation and Estimation of Various Markov Models with Applications to Membrane Channel Kinetics
Authors: Pulford G. W. , Gallant J. C. , Kennedy R. A. , Chung S. H. 
Published: May 2007

AbstractHidden Markov modelling is a powerful and efficient digital signal processing strategy for extracting the maximum likelihood model from a finite length sample of noisy data. Assuming the number of states in the model is known, then the state levels, transition probabilities, initial state distribution and the noise variance can be estimated. We investigate the applicability of this technique in membrane channel kinetics not only as a parameter estimator, but also as an aid to discriminating between various model types according to their statistical likelihood. We survey three representative classes of channel dynamics, namely: aggregated Markov models, semi‐Markov models (with asymptotically convergent transition probabilities), and coupled Markov models; reformulating each within a discrete‐time hidden Markov model framework. We then provide numerical evidence of the effectiveness of the procedure using simulated channel data and hence show that the correct model, as well as the model parameters, can be discerned. We also demonstrate that the model likelihood can be used to indicate the approximate number of states in the model.
Efficiency Indices for Second‐Order Designs
Authors: Jensen D. R. 
Published: May 2007

AbstractDesign efficiencies are studied for inferences regarding the coefficients of second‐order models. Subspaces of parameters are identified wherein each of two designs dominates the other locally, or the two designs are equally efficient. Both Fisher efficiency in estimation and Pitman efficiency in hypothesis testing are considered. Eight small second‐order designs ink=3 regressor variables are screened using a four‐part efficiency index. Of these, the central composite, Box‐Behnken, small composite, and hybrid H310 and H311 B designs are found to be generally superior and roughly comparable. Detailed comparisons among these five designs are then undertaken. This work provides further tools for use in design evaluation, requiring only basic matrix operations independently of experimental data.
The Structure of Compounded Trivariate Binomial Distributions
Authors: Papageorgiou H. , David Katerina M. 
Published: May 2007

AbstractA family of trivariate binomial mixtures with respect to their exponent parameter is introduced and its structure is studied by the use of probability generating functions. Expressions for probabilities, factorial moments and factorial cumulants are given. Conditional distributions are also examined. Illustrative examples include the trivariate Poisson, binomial, negative binomial and modified logarithmic series distributions. In addition, properties of the compounded trivariate Poisson distribution are discussed. Finally biological, medical and ecological applications are indicated.
A Bivariate Discrete Charlier Series Distribution
Authors: Papageorgiou H. , Loukas S. , Loukas S. 
Published: May 2007

AbstractA bivariate distribution is introduced with marginals convolutions of a binomial and a Poisson random variables. Various properties of the distribution are examined. Estimation is discussed and illustrated by fitting the distribution to two sets of data. An application to ornithology is also indicated.
Estimation of Variance Components Based on Partial Triallel Mating Design
Authors: Srinivasan M. R. , Ponnuswamy K. N. 
Published: May 2007

AbstractThe higher order mating designs like triallel and double crosses have been found to be useful in exploiting the epistatic gene action. However, it is equally important to note that enormous amount of resources are necessary to develop triallel crosses even for a small number of genetic lines p as it involves developing p(p—1)(p—2)/2 distinct three way hybrids. A simple answer to this problem is to consider a sample of triallel crosses known as partial triallel crosses (PTC) which retains the salient properties of triallel crosses at less cost. In this paper we consider the estimation of variance components (design and genetic) based on partial triallel mating designs.
Distribution‐free Partially Sequential Tests for Treatments Versus Control Setting
Authors: Kim Dongjae , Wolfe Douglas A. 
Published: May 2007

AbstractIn this paper we propose a class of distribution‐free tests for the treatments versus control setting using the partially sequential sampling technique. Expressions for the asymptotic distributions and power for the tests are provided and criteria for adapting a particular test to have asymptotic power restrictions against alternatives of interest are discussed. Comparative results of a Monte Carlo power study are also presented.
Approximate Confidence Intervals for Contrasts in the Balanced Three Factor Mixed Model
Authors: Mosier Michael C. , Graybill Franklin A. 
Published: May 2007

AbstractWhen conducting a statistical analysis of data from a designed experiment, an investigator is often interested in confidence intervals for contrasts of the fixed effects. If the analysis involves a mixed linear model, exact confidence intervals for contrasts of the fixed effects are not always available. In such cases, confidence intervals with approximate coverage probabilities must be used.As will be shown, this problem may be generalized to that of constructing a confidence interval for the parameter μ, where X is a normal random variable with mean μ and variance ∑ aqθq, where a1…,aQ are known constants, Uq = nqS/θq is a chi‐squared random variable with nq degrees of freedom, for each q = 1,…, Q, and X,U1,…, UQ are mutually independent. In this paper, we consider the case where Q = 3 and a3 ≤0.