bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bayesian Inference for Non-Gaussian Ornstein–Uhlenbeck Stochastic Volatility Processes
Authors: Roberts Gareth O. , Papaspiliopoulos Omiros , Dellaportas Petros 
Published: December 2004

SummaryWe develop Markov chain Monte Carlo methodology for Bayesian inference for non-Gaussian Ornstein–Uhlenbeck stochastic volatility processes. The approach introduced involves expressing the unobserved stochastic volatility process in terms of a suitable marked Poisson process. We introduce two specific classes of Metropolis–Hastings algorithms which correspond to different ways of jointly parameterizing the marked point process and the model parameters. The performance of the methods is investigated for different types of simulated data. The approach is extended to consider the case where the volatility process is expressed as a superposition of Ornstein–Uhlenbeck processes. We apply our methodology to the US dollar–Deutschmark exchange rate.
Identification of Non-Linear Additive Autoregressive Models
Authors: Huang Jianhua Z. , Yang Lijian 
Published: December 2004

SummaryWe propose a lag selection method for non-linear additive autoregressive models that is based on spline estimation and the Bayes information criterion. The additive structure of the autoregression function is used to overcome the ‘curse of dimensionality’, whereas the spline estimators effectively take into account such a structure in estimation. A stepwise procedure is suggested to implement the method proposed. A comprehensive Monte Carlo study demonstrates good performance of the method proposed and a substantial computational advantage over existing local-polynomial-based methods. Consistency of the lag selection method based on the Bayes information criterion is established under the assumption that the observations are from a stochastic process that is strictly stationary and strongly mixing, which provides the first theoretical result of this kind for spline smoothing of weakly dependent data.
Recent Developments in Oestrous Synchronization of Postpartum Dairy Cows with and without Ovarian Disorders
Authors: Yániz JL , Murugavel K , López‐Gatius F 
Published: December 2004

ContentsThis report reviews the most recent developments in prostaglandin‐based oestrous synchronization programmes for postpartum dairy cows and addresses the efficiency of controlled breeding protocols based on such developments for cows with abnormal ovarian conditions. A double prostaglandin protocol applied 11–14 days apart seems to be capable of bringing most cows to oestrus. Because of varying oestrus onset times, improved conception rates are obtained following artificial insemination (AI) at detected oestrus rather than fixed‐time AI in prostaglandin‐treated cows. The administration of oestradiol or human chorionic gonadotrophin, or both these hormones, after prostaglandin treatment, improves the synchrony of oestrus yet does not enhance the conception rate. Progesterone‐based treatments for oestrous synchronization are considered the most appropriate for non‐cyclic or anoestrous postpartum dairy cows; prostaglandin alone being ineffective because of the absence of a mature corpus luteum in these cows. Improved oestrus synchrony and fertility rate have been reported using short‐term progesterone treatment regimes (7–9 days) with or without oestradiol benzoate combined with the use of a luteolytic agent given 1 day before, or at the time of, progesterone withdrawal. The ovulation synchronization (Ovsynch) protocol, based on the use of gonadotrophin releasing hormone and prostaglandin, was developed to coordinate follicular recruitment, CL regression and the time of ovulation. This protocol allows fixed time insemination and has proved effective in improving reproductive management in postpartum dairy cows. However, timed AI following Ovsynch seems to have no beneficial effects in heifers, because of an inconsistent follicle wave pattern, and in anoestrous cows, given their lack of prostaglandin responsive CL. To date, there are several prostaglandin based, fixed‐time insemination oestrous synchronization protocols for use in early postpartum dairy cows with ovarian disorders such as ovarian cysts and acyclicity.
Repeatability and Heritability of Ovulation Number and Embryos in Dam‐daughters Pairs in Superovulated Holstein–Friesian Cows
Authors: Bényei B , Gáspárdy A , Komlósi I , Pécsi A 
Published: December 2004

ContentsHolstein–Friesian dams (n = 28) and daughters (n = 28) were superovulated (total number of observations was 235) to determine the repeatability and heritability of ovulation number and embryo collection result for FSH treatment. The donor cows were superovulated with FSHp, artificial insemination was performed and embryo collection was carried out 7 days later. For the analysis, the raw corpdata of the number of corpora lutea (CL), the number of collected embryos (EM) and their log‐transformed values were used (log CL, log EM). The genetic parameters were calculated by using the VCE4 software. For calculating heritability, the number of embryo collection was used as a random effect; for calculating repeatability, the permanent environment was fitted. The additive genetic variance of CL was 8.91 and that of the EM was 9.23. The additive genetic variance for the log CL and log EM were 0.457 and 0.340, respectively. The estimated heritability for CL and EM were 0.234 and 0.159, and repeatability were 0.386 and 0.301, respectively. Higher heritabilities but lower as the previous repeatabilities were observed for the log‐transformed data, 0.266, 0.194 and 0.294, 0.208 for log CL and for log EM, respectively.
Studies on Motility and Fertility of Cooled Stallion Spermatozoa
Authors: Rota A , Furzi C , Panzani D , Camillo F 
Published: December 2004

ContentsThis study on extended, cooled stallion spermatozoa aimed to compare the ability of three extenders to maintain sperm motility during 24 h of preservation, and to describe pregnancy and foaling rates after artificial insemination (AI) of stallion spermatozoa stored and transported in the extender chosen from thein vitrostudy. After 6 and 24 h of preservation, motility, both subjective and evaluated by the motility analyzer (total, progressive and rapid), was lower in non‐fat, dried skim milk–glucose than in both other extenders: dried skim milk–glucose added to 2% centrifuged egg yolk, and ultra high temperature treated skim milk–sugar‐saline solution added to 2% centrifuged egg yolk (INRA82‐Y). Rapid spermatozoa and sperm velocity parameters, after 24 h, were significantly higher in INRA82‐Y. In the fertility trial, semen collected from three Maremmano stallions, diluted in INRA82‐Y, and transported in a refrigerated Styrofoam box, was used to inseminate 56 mares of the same breed. Pregnancy rates after the first cycle and per breeding season were significantly higher for the 31 mares inseminated in three AI centres (54.8 and 80.6%, respectively) than for the 25 mares inseminated at the breeder's facilities (28.0 and 52.0%). Foaling rates were not significantly different between the AI centres mares (54.8%) and the other mares (44.0%). In conclusion, INRA82‐Y yielded satisfactory pregnancy and foaling rates, especially when employed in the more controlled situation of an AI centre, and can therefore be included among those available for cooled stallion semen preservation.
Evaluation of tissue specificity and expression strength of rice seed component gene promoters in transgenic rice
Authors: Qu Le Qing , Takaiwa Fumio 
Published: December 2004

SummaryUsing stable transgenic rice plants, the promoters of 15 genes expressed in rice seed were analysed for their spatial and temporal expression pattern and their potential to promote the expression of recombinant proteins in seeds. The 15 genes included 10 seed storage protein genes and five genes for enzymes involved in carbohydrate and nitrogen metabolism. The promoters for the glutelins and the 13 kDa and 16 kDa prolamins directed endosperm‐specific expression, especially in the outer portion (peripheral region) of the endosperm, whilst the embryo globulin and 18 kDa oleosin promoters directed expression in the embryo and aleurone layer. Fusion of the GUS gene to the 26 kDa globulin promoter resulted in expression in the inner starchy endosperm tissue. It should be noted that the 10 kDa prolamin gene was the only one tested that required both the 5′ and 3′ flanking regions for intrinsic endosperm‐specific expression. The promoters from the pyruvate orthophosphate dikinase (PPDK) and ADP‐glucose pyrophosphorylase (AGPase) small subunit genes were active not only in the seed, but also in the phloem of vegetative tissues. Within the seed, the expression from these two promoters differed in that the PPDK gene was only expressed in the endosperm, whereas the AGPase small subunit gene was expressed throughout the seed. The GUS reporter gene fused to the alanine aminotransferase (AlaAT) promoter was expressed in the inner portion of the starchy endosperm, whilst the starch branching enzyme (SBE1) and the glutamate synthase (GOGAT) genes were mainly expressed in the scutellum (between the endosperm and embryo). When promoter activities were examined during seed maturation, the glutelin GluB‐4, 26 kDa globulin and 10 kDa and 16 kDa prolamin promoters exhibited much higher activities than the others. The seed promoters analysed here exhibited a wide variety of activities and expression patterns, thus providing many choices suitable for various applications in plant biotechnology.
Gene expression patterns to define stages of post‐harvest senescence in Alstroemeria petals
Authors: Breeze Emily , Wagstaff Carol , Harrison Elizabeth , Bramke Irene , Rogers Hilary , Stead Anthony , Thomas Brian , Buchanan‐Wollaston Vicky 
Published: December 2004

SummaryPetal senescence in many species is regulated by ethylene but some flowers, such as those on the monocotyledonous plant Alstroemeria, var. Rebecca are ethylene insensitive. Changes in gene expression during the post‐harvest senescence of Alstroemeria flowers were investigated using several different techniques. Suppressive subtractive hybridization (SSH) was used to obtain cDNA libraries enriched for genes expressed at selected stages of petal senescence. Sequencing of the EST clones obtained resulted in over 1000 sequences that represent approximately 500 different genes. Analysis of the potential functions of these genes provides a snapshot of the processes that are taking place during petal development. Both cell wall related genes and genes involved in metabolism were present at a higher proportion in the earlier stages. Genes encoding metal binding proteins (mostly metallothionein‐like) were the major component of senescence enhanced libraries. This limited the diversity of genes identified showing differential expression at the later stages. Changes in the expression of all genes were analysed using microarray hybridization, and genes showing either up or down‐regulation were identified. The expression pattern of a selection of genes was confirmed using Northern hybridization. Northern hybridization confirmed the up‐regulation of metallothioneins after floral opening, however, this was not detected by the microarray analysis, indicating the importance of using a combination of methods to investigate gene expression patterns. Considerably more genes were up‐regulated than down‐regulated. This may reflect the need during Alstroemeria petal senescence for the expression of a whole new set of genes involved with degradation and mobilization. The potential uses of expression profiling to improve floral quality in breeding programmes or as a diagnostic tool are discussed.
Production and glycosylation of plant‐made pharmaceuticals: the antibodies as a challenge
Authors: Gomord Véronique , Sourrouille Christophe , Fitchette Anne‐Catherine , Bardor Muriel , Pagny Sophie , Lerouge Patrice , Faye Loïc 
Published: December 2004

SummaryAntibodies have long been recognized for their diagnostic and therapeutic potential. The rapidly increasing number of monoclonal antibodies approved for immunotherapy has paved the way to an even greater demand for these molecules. In order to satisfy this growing demand and to increase the production capacity, alternative systems based on antibody production in transgenic organisms are being actively explored. In this paper, we focus on transgenic plants as a promising system for the scale‐up and processing of plant‐made pharmaceuticals. In particular, we point out the advantages and limitations induced by glycosylation of plant‐made antibodies for human therapy.
Robust Automatic Methods for Outlier and Error Detection
Authors: Chambers Ray , Hentges Adão , Zhao Xinqiang 
Published: December 2004

SummaryEditing in surveys of economic populations is often complicated by the fact that outliers due to errors in the data are mixed in with correct, but extreme, data values. We describe and evaluate two automatic techniques for the identification of errors in such long-tailed data distributions. The first is a forward search procedure based on finding a sequence of error-free subsets of the error-contaminated data and then using regression modelling within these subsets to identify errors. The second uses a robust regression tree modelling procedure to identify errors. Both approaches can be implemented on a univariate basis or on a multivariate basis. An application to a business survey data set that contains a mix of extreme errors and true outliers is described.
Analysis of Longitudinal Data Unbalanced Over Time
Authors: Huang Wenzheng , Fitzmaurice Garrett M. 
Published: December 2004

SummaryThe paper considers modelling, estimating and diagnostically verifying the response process generating longitudinal data, with emphasis on association between repeated meas-ures from unbalanced longitudinal designs. Our model is based on separate specifications of the moments for the mean, standard deviation and correlation, with different components possibly sharing common parameters. We propose a general class of correlation structures that comprise random effects, measurement errors and a serially correlated process. These three elements are combined via flexible time-varying weights, whereas the serial correlation can depend flexibly on the mean time and lag. When the measurement schedule is independent of the response process, our estimation procedure yields consistent and asymptotically normal estimates for the mean parameters even when the standard deviation and correlation are misspecified, and for the standard deviation parameters even when the correlation is misspecified. A generic diagnostic method is developed for verifying the models for the mean, standard deviation and, in particular, the correlation, which is applicable even when the data are severely unbalanced. The methodology is illustrated by an analysis of data from a longitudinal study that was designed to characterize pulmonary growth in girls.
Improved Unbiased Estimators in Adaptive Cluster Sampling
Authors: Dryver Arthur L. , Thompson Steven K. 
Published: December 2004

SummaryThe usual design-unbiased estimators in adaptive cluster sampling are easy to compute but are not functions of the minimal sufficient statistic and hence can be improved. Improved unbiased estimators obtained by conditioning on sufficient statistics—not necessarily minimal—are described. First, estimators that are as easy to compute as the usual design-unbiased estimators are given. Estimators obtained by conditioning on the minimal sufficient statistic which are more difficult to compute are also discussed. Estimators are compared in examples.
Evolution of zygomorphy in monocot flowers: iterative patterns and developmental constraints
Authors: Rudall Paula J. , Bateman Richard M. 
Published: December 2004

SummaryHere we explore morphological transitions among monocot flowers and discuss them in terms of modification of existing structures. Monocot flowers are typically arranged in five whorls (carpels, inner and outer stamens, inner and outer tepals), and are radially symmetrical, constructed around a 3‐fold axis of rotational symmetry that delineates three planes of bilateral symmetry. Differential development of one or two of the three organs within a whorl inevitably emphasizes one plane of symmetry, by eliminating the other planes, rendering the whorl zygomorphic. Zygomorphy (monosymmetry) has evolved more than once in monocotyledons. Stamen suppression is a widespread aspect of zygomorphy and conforms to two broad categories of pattern. In the more frequent Pattern 1, 1–3(−5) adaxial stamens (both inner and outer) are either reduced in size or entirely suppressed. Pattern 2 involves loss, reduction or modification of at least the outer abaxial stamen. Pattern 2 often characterizes groups that are phylogenetically embedded within Pattern 1 clades, perhaps indicating that this pattern results from loss of function or overexpression of the same genes involved in establishment of Pattern 1. Heterotopy has been an important evolutionary phenomenon among Zingiberales (some stamens becoming petaloid) and perhaps grasses (petals possibly becoming sepaloid). Heterochrony is the most frequent cause of more subtle changes in the degree of bilateral symmetry shown by monocot flowers by enhancing (peramorphosis) or retarding (paedomorphosis) individual organs within specific whorls.

Contents

Summary
25

I.
Introduction
28

II.
Background
27

III.
Asparagales
28

IV.
Commelinids: ZHC clade
29

V.
Commelinids: Poales
32

VI.
Conceptual transitions among floral forms revisited
34

VII.
Examples from monocot flowers
37

VIII.
Specific cases of ontogenetic transitions between contrasting floral morphs
39

IX.
Conclusions
40

Acknowledgements
42

References
42
The evolution of polymorphic sexual systems in daffodils (Narcissus)
Authors: Barrett Spencer C. H. , Harder Lawrence D. 
Published: December 2004

Summary Narcissus, the daffodil genus, exhibits an unusual diversity of sexual systems, with populations that are monomorphic, dimorphic or trimorphic for style length. Associated with this variation are striking differences among species in floral morphology and pollination biology. This diversity provides an opportunity to investigate the evolution of mating polymorphisms, and to determine how floral morphology promotes transitions among sexual systems. Because of the absence of heteromorphic incompatibility in Narcissus, floral morphology plays a key role in governing patterns of outcrossed mating. Phylogenetic evidence indicates that stylar monomorphism is ancestral in the genus, with multiple origins of stylar polymorphism, including independent origins of stigma‐height dimorphism, distyly and tristyly. Sexual polymorphisms have evolved only in lineages with narrow floral tubes that are pollinated by Lepidoptera and/or long‐tongued bees. Populations of polymorphic Narcissus species are typically dominated by the long‐styled morph and display imperfect reciprocity in the positions of sexual organs. These features are consequences of the unusual association between stylar polymorphism and a self‐incompatibility system that permits intramorph mating.
Plant venereal diseases: insights from a messy metaphor
Authors: Antonovics Janis 
Published: December 2004

SummaryThe concept of plant venereal disease is examined from definitional, operational and axiomatic viewpoints. The transmission of many plant pathogens occurs during the flowering phase and is effected either by pollinators or by wind dispersal of spores from inflorescences. Attraction of insects by pseudo‐flowers or sugary secretions also serves to spread many diseases. Given the diversity of processes involved, a simple all‐encompassing parallel with animal venereal diseases is not possible. Operationally establishing the routes of disease transmission, as well as quantifying the relative magnitudes of these different routes, remains critical for understanding disease dynamics and controlling spread in agricultural contexts. From an axiomatic viewpoint, sexually transmitted diseases are characterized by frequency‐dependent transmission, transmission in the adult stage, and by virulence effects involving sterility rather than mortality. These characteristics serve to differentiate the dynamics and evolution of sexually transmitted diseases from that of other diseases and are features that are also shared by many pollinator‐transmitted diseases. However, the majority of plant diseases that involve the reproductive structures show a rich biology that defies easy categorization. The experimental convenience of plants and their pathogens is likely to play an important role in understanding the evolution of disease traits, irrespective of what descriptive terms are applied to the natural history of the transmission process.
Randomization tests for ERP topographies and whole spatiotemporal data matrices
Authors: Maris Eric 
Published: December 2004

AbstractIn ERP studies, the comparison of topographies (multichannel measurements) or whole spatiotemporal data matrices (multichannel time series of measurements), the classical statistical tests very often cannot be used. It is argued that, for these comparisons, randomization tests are an excellent alternative. It is also argued that the randomization test is superior to another resampling method, the bootstrap, because exact probability statements (e.g., p values) can be made. A review is given of the literature on randomization tests designed for electrophysiological data. New randomization tests are presented and applied to two data sets, one coming from a psychopharmacological experiment and the other from an ERP experiment in visual word recognition.
The selective processing of briefly presented affective pictures: An ERP analysis
Authors: Schupp Harald T. , Junghöfer Markus , Weike Almut I. , Hamm Alfons O. 
Published: December 2004

AbstractRecent event‐related potential (ERP) studies revealed the selective processing of affective pictures. The present study explored whether the same phenomenon can be observed when pictures are presented only briefly. Toward this end, pleasant, neutral, and unpleasant pictures from the International Affective Pictures Series were presented for 120 ms while event related potentials were measured by dense sensor arrays. As observed for longer picture presentations, brief affective pictures were selectively processed. Specifically, pleasant and unpleasant pictures were associated with an early endogenous negative shift over temporo‐occipital sensors compared to neutral images. In addition, affective pictures elicited enlarged late positive potentials over centro‐parietal sensor sites relative to neutral images. These data suggest that a quick glimpse of emotionally relevant stimuli appears sufficient to tune the brain for selective perceptual processing.
Mutational screening of the CD40 ligand (CD40L) gene in patients with X linked hyper-IgM syndrome (XHIM) and determination of carrier status in female relatives: Table 1
Authors: Prasad M L , Velickovic M , Weston S A , Benson E M 
Published: December 2004

Aims:To analyse the gene encoding the CD40 ligand (CD40L) in 11 Australian patients from 10 unrelated families with the X linked hyper-IgM (XHIM) phenotype.Methods:The CD40L gene was screened for mutations using direct sequencing of exon specific polymerase chain reaction (PCR) products.Results:Ten mutations were identified. Seven of these mutations have been described previously, whereas three new nonsense mutations were identified, namely: E108X (c.322G>T), G167X (c.499G>T), and C218X (c.654C>A). Ten of 15 female family members revealed both a mutated allele and a normal allele, indicating that they were XHIM carriers.Conclusion:The 10 mutations (including the three new ones) identified in this study reflect the heterogeneity of the CD40L gene, and indicate the need for accurate and reliable molecular testing of those patients suspected of XHIM.