bluuebunny/crossref_metadata_2025 huggingface dataset:
Electrospray ionization mass spectrometry: a key analytical tool for the characterization of regioselectively derivatized maltooligosaccharides obtained starting from natural β‐cyclodextrin
Authors: Lesur David , Gassama Abdoulaye , Moreau Vincent , Djedaïni‐Pilard Florence , Brique Arnaud , Pilard Serge
Published: February 2006

The development of natural cyclodextrins (CDs) for various industrial applications (agroalimentary, cosmetic or pharmaceutical) constitutes a continuous challenge. For the integration of these agricultural plant products in the creation of super‐absorbent biodegradable and hypoallergenic materials (water‐retaining agents, cosmetic hydrating and texturing, pharmaceutical and horticultural products) to replace synthetic polymers, we have developed chemical methods to access regioselectively C‐6‐derivatized maltooligosaccharides starting from CDs. These compounds are highly suitable for further chemical modifications and are expected to give access to a new class of polymeric materials with potential applications such as water‐retaining agents in the disposable nappies industry. For the structural analysis of carbohydrates, electrospray ionization mass spectrometry (ESI‐MS) offers precise results, analytical versatility and very high sensitivity. We report herein the rapid and convenient follow‐up of chemical reactions, the purity evaluation of intermediates and final products, and the structural characterization of derivatized maltooligosaccharides, obtained by acidic cleavage (acetolysis) of halogenated and esterified CDs, using ESI‐MS in combination with the high‐resolution (HRMS) and tandem mass spectrometry (MS/MS) capabilities of a quadrupole orthogonal time‐of‐flight (Q‐TOF) mass spectrometer. Copyright © 2006 John Wiley & Sons, Ltd.
Cluster detection diagnostics for small area health data: with reference to evaluation of local likelihood models
Authors: Monir Hossain Md. , Lawson Andrew B.
Published: February 2006

The focus of this paper is the development of a range of cluster detection diagnostics that can be used to assess the degree to which a clustering method recovers the true clustering behaviour of small area data. The diagnostics proposed range from individual region specific diagnostics to neighbourhood diagnostics, and assume either individual region risk as focus, or concern areas of maps defined to be clustered and the recovery ability of methods. A simulation‐based comparison is made between a small set of count data models: local likelihood, BYM and Lawson and Clark. It is found that local likelihood has good performance across a range of criteria when a CAR prior is assumed for the lasso parameter. Copyright © 2006 John Wiley & Sons, Ltd.
Evaluating spatial surveillance: detection of known outbreaks in real data
Authors: Kleinman Ken , Abrams Allyson , Katherine Yih W. , Platt Richard , Kulldorff Martin
Published: February 2006

Since the anthrax attacks of October 2001 and the SARS outbreaks of recent years, there has been an increasing interest in developing surveillance systems to aid in the early detection of such illness. Systems have been established which do this is by monitoring primary health‐care visits, pharmacy sales, absenteeism records, and other non‐traditional sources of data. While many resources have been invested in establishing such systems, relatively little effort has as yet been expended in evaluating their performance.

One way to evaluate a given surveillance system is to compare the signals it generates with known outbreaks identified in other systems. In public health practice, for example, public health departments investigate reports of illness and sometimes track hospital admissions. Comparison of new systems with extant systems cannot generate estimates of test characteristics such as sensitivity and specificity, since the actual number of positives and negatives cannot be known. However, the comparison can reveal whether a new or proposed system's signals match outbreaks detected by the existing system. This could help support or reject the new system as an alternative or complement to the extant system.

We propose three methods to test the null hypothesis that the new system does not signal true outbreaks more often than would be expected by chance. The methods differ in the restrictiveness of the assumptions required. Each test may detect weaknesses in the new system, depending on the distribution of outbreaks and can be used to construct confidence limits on the agreement between the new system's signals and the outbreaks, given the distribution of the signals. They can be used to assess whether the new system works in that it detects the outbreaks better than chance would suggest and can also determine if the new systems' signals are generated earlier than an extant system. Copyright © 2006 John Wiley & Sons, Ltd.
A workflow spatial scan statistic
Authors: Duczmal Luiz , Buckeridge David L.
Published: February 2006

We propose a modification of the spatial scan statistic that takes account of workflow, which is the movement of individuals between home and work. The objective is to detect clusters of disease in situations where exposure occurs in the workplace, but only home address is available for analysis. In these situations, application of the usual spatial scan statistic does not account for possible differences between home and work address, thereby reducing the power of detection. We describe an extension to the usual spatial scan statistic that uses workflow data to search for disease clusters resulting from workplace exposure. We also present results from simulations that demonstrate the increased power of the workflow scan statistic over the usual scan statistic for detecting clusters arising from exposures in the workplace. Copyright © 2006 John Wiley & Sons, Ltd.
Multiscale detection of localized anomalous structure in aggregate disease incidence data
Authors: Louie Mary M. , Kolaczyk Eric D.
Published: February 2006

We present a modelling framework for detection of potentially anomalous structure in aggregate spatial disease incidence data in a manner sensitive to localization at multiple scales and/or positions. The key technical contribution is the re‐casting of the components of a multiscale disease mapping methodology, recently introduced by the authors in an earlier paper, into a form appropriate for hypothesis testing. In particular, we describe how hypotheses of spatially clustered variations in disease incidence may be linked in one‐to‐one correspondence with collections of hypotheses on the values of certain multiscale parameters associated with a user‐defined hierarchy of nested partitions of an overall spatial region. A Bayesian hypothesis testing methodology is developed in the context of a standard Poisson measurement model, over the collection of possible multiscale hypotheses. We discuss the specification of hyper parameters and prior distributions on the space of models. The methodology is illustrated on both simulated and real data. Copyright © 2006 John Wiley & Sons, Ltd.
Impact of prior choice on local Bayes factors for cluster detection
Authors: Gangnon Ronald E.
Published: February 2006

In this paper, we evaluate the usefulness of local Bayes factors as a tool for spatial cluster detection. In particular, we consider whether local Bayes factors from models with a fixed, but overly large number of clusters can consistently identify the evidence for clustering for a variety of prior specifications for the cluster locations. We also investigate the robustness of the local Bayes factor to the number of clusters included in the model. We explore the impacts of prior choice for cluster location and the number of clusters on posterior inference for disease rates. We conduct the comparison by analysing data on 1990 breast cancer incidence in Wisconsin. Copyright © 2006 John Wiley & Sons, Ltd.
Fast detection of arbitrarily shaped disease clusters
Authors: Assunção R. , Costa M. , Tavares A. , Ferreira S.
Published: February 2006

Disease cluster detection and evaluation have commonly used spatial statistics methods that scan the map with a fixed circular window to locate candidate clusters. Recently, there has been interest in searching for clusters with arbitrary shape. The circular scan test retains high power of detecting a cluster, but does not necessarily identify the exact regions contained in a non‐circular cluster particularly well. We propose, implement and evaluate a new procedure that is fast and produces clusters estimates of arbitrary shape in a rich class of possible cluster candidates. We showed that our methods contain the so‐called upper level set method as a particular case. We present a power study of our method and, among other results, the main conclusion is that the likelihood‐based arbitrarily shaped scan method is not appropriate to find a cluster estimate. When the parameter space includes the set of all possible spatial clusters in a map, a large and discrete parameter space, maximum likely cluster estimates tend to overestimate the true cluster by a large extent. This calls for a new approach different from the maximum likelihood method for this important public health problem. Copyright © 2006 John Wiley & Sons, Ltd.
The geography of power: statistical performance of tests of clusters and clustering in heterogeneous populations
Authors: Waller Lance A. , Hill Elizabeth G. , Rudd Rose Anne
Published: February 2006

Heterogeneous population densities complicate comparisons of statistical power between hypothesis tests evaluating spatial clusters or clustering of disease. Specifically, the location of a cluster within a heterogeneously distributed population at risk impacts power properties, complicating comparisons of tests, and allowing one to map spatial variations in statistical power for different tests. Such maps provide insight into the overall power of a particular test, and also indicate areas within the study area where tests are more or less likely to detect the same local increase in relative risk. While such maps are largely driven by local sample size, we also find differences due to features of the statistics themselves. We illustrate these concepts using two tests: Tango's index of clustering and the spatial scan statistic. Furthermore, assessments of the accuracy of the ‘most likely cluster’ involve not only statistical power, but also spatial accuracy in identifying the location of a true underlying cluster. We illustrate these concepts via induction of artificial clusters within the observed incidence of severe cardiac birth defects in Santa Clara County, CA in 1981. Copyright © 2006 John Wiley & Sons, Ltd.
An extended power of cluster detection tests
Authors: Takahashi Kunihiko , Tango Toshiro
Published: February 2006

Several tests have been proposed to detect spatial disease clustering without prior information on their locations. In order to compare the performance of these tests, most authors employ the usual power, i.e. the rejection probability of the null hypothesis of no clustering due to various reasons. However, the usual power is not always appropriate for evaluating the cluster detection tests since their purpose is to both reject the null hypothesis and identify the cluster areas accurately. In this paper, we propose an extended power of the cluster detection tests, which includes the usual power as a special case. Further, we define the profile of the extended power, which can be expected to play an important role in the evaluation and comparison of several cluster detection tests. The proposed extended power and its profile are demonstrated by two tests—Kulldorff's circular spatial scan statistic and a flexible spatial scan statistic proposed by Tango and Takahashi. Copyright © 2006 John Wiley & Sons, Ltd.
A cluster model for space–time disease counts
Authors: Yan Ping , Clayton Murray K.
Published: February 2006

Modelling disease clustering over space and time can be helpful in providing indications of possible exposures and planning corresponding public health practices. Though a considerable number of studies focus on modelling spatio‐temporal patterns of disease, most of them do not directly model a spatio‐temporal clustering structure and could be ineffective for detecting clusters. In this paper, we extend a purely spatial cluster model to accommodate space–time clustering. Inference is performed in a Bayesian framework using reversible jump Markov chain Monte Carlo. This idea is illustrated using data on female breast cancer mortality from Japan. A hierarchical parametric space–time model for mapping disease is used for comparison. Copyright © 2006 John Wiley & Sons, Ltd.
Statistical methods for the detection of spatial clustering in case–control data
Authors: Rogerson Peter A.
Published: February 2006

In this paper, I develop new approaches for the detection of spatial clustering in case–control data. One method is based upon drawing Thiessen polygons around each control. It is unnecessary to actually draw or compute the boundaries of the polygons; it is sufficient to count, for each control, the number of cases that are closer to that control than to any other control. A second method is similar to the Cuzick–Edwards method, which is based on counts of cases that are among thek‐nearest neighbours of cases, but is instead based upon the number of cases within a specified distance of cases. These first two methods are global methods in the sense that they provide a single statistic that measures the degree of spatial clustering. The third method suggests a local statistic, for tests of the null hypothesis of no spatial clustering around a prespecified focus. The method is based upon the cumulative χ2test, which is typically used to test whether cases are more prevalent than expected around a prespecified location. This is also extended to the case where all observational locations are considered as potential cluster locations and multiple testing is carried out. Each of the new methods is illustrated using data on childhood leukaemia and lymphoma cases in North Humberside. Copyright © 2006 John Wiley & Sons, Ltd.
Likelihood based tests for spatial randomness
Authors: Song Changhong , Kulldorff Martin
Published: February 2006

Many different methods have been proposed to test the spatial randomness of a point pattern adjusting for an inhomogeneous background population. These tests can be classified into cluster detection tests, concerned with the detection and inference of local clusters, and global clustering tests, which collect evidence for clustering throughout the study region. This paper is mainly concerned about global clustering tests.

Some tests for spatial randomness are based on likelihoods, which include the spatial and space–time scan statistics with variable window size and Gangnon and Clayton's weighted average likelihood ratio tests. Both of these tests perform well compared to other tests for cluster detection and global clustering, respectively. In this study, we develop other likelihood based tests for global clustering and we explore the use of different weight functions with these tests. The power of these tests is evaluated using simulated data set and compared with existing methods. Copyright © 2006 John Wiley & Sons, Ltd.
The practical application of a mathematical model to predict the outcome of pregnancies of unknown location
Authors: Kirk E. , Condous G. , Haider Z. , Lu C. , Van Huffel S. , Timmerman D. , Bourne T.
Published: February 2006

Objective

A logistic regression model has been developed previously to predict which pregnancies of unknown location (PULs) become ectopics. This model was based on the human chorionic gonadotropin (hCG) ratio (hCG 48 h/hCG 0 h). The aim of this study was to evaluate the model in an early pregnancy clinical setting.

Methods

This was a prospective non‐interventional observational study. Women classified as having a PUL had serum hCG and progesterone levels taken at presentation and 48 h later. At 48 h, nurse practitioners in the early pregnancy unit gave their subjective assessment of the likely pregnancy outcome based upon existing strategies to predict the outcome of PULs and their own previous experience. This was used as the basis for the clinical management of the women. The hormonal data were then entered into the model, which was available on the clinic computer in the form of a Microsoft Excel package, and the predicted outcome according to this model was recorded for each case. The model was weighted in favor of detecting an ectopic pregnancy at the expense of failing PULs and intrauterine pregnancies. All women were followed up until the final true diagnosis was established: a failing PUL, an intrauterine pregnancy or an ectopic pregnancy. The predicted outcome according to the model was compared with that of the subjective assessment of the expert operator and the true outcome after follow‐up.

Results

Data were obtained from 357 women classified as having PULs. The final clinical outcomes were: 162 (45.4%) failing PULs, 166 (46.5%) intrauterine pregnancies and 29 (8.1%) ectopic pregnancies. Subjective assessment utilizing current strategies gave sensitivities of 79.3%, 92.8% and 87.0% for the detection of ectopic pregnancy, intrauterine pregnancy and failing PUL, respectively. The model detected ectopic pregnancy, intrauterine pregnancy and failing PUL with sensitivities of 82.8%, 86.8% and 73.5%, respectively. There were no adverse outcomes.

Conclusion

This logistic regression model, based on the hCG ratio, can be used to predict the outcome of PULs, especially the ectopic pregnancies, with a high degree of certainty. It compares favorably with subjective assessment by experienced operators using current strategies to predict the outcome of PULs. The model can be used by those with limited knowledge or understanding of the behavior of serum biochemistry in the first trimester and in turn aid in the classification of PULs into those at low and those at high risk of ectopic pregnancy at 48 h. Copyright © 2006 ISUOG. Published by John Wiley & Sons, Ltd.
Prenatal diagnosis of persistent left superior vena cava and its associated congenital anomalies
Authors: Berg C. , Knüppel M. , Geipel A. , Kohl T. , Krapp M. , Knöpfle G. , Germer U. , Hansmann M. , Gembruch U.
Published: February 2006

Objective

To evaluate the associated conditions and the outcome of persistent left superior vena cava (PLSVC) detected in fetal life.

Methods

This was a retrospective review of all cases of PLSVC detected prenatally between 1998 and 2004 in two tertiary referral centers in Germany. Patient charts, ultrasound video recordings and still frames of all cases were reviewed for associated conditions and outcome.

Results

Eighty‐two cases of PLSVC were detected in the study period. Thirty‐seven cases (45%) were associated with heterotaxy syndromes, 19 (23%) with isolated cardiac malformations, seven (9%) with aneuploidy, six (7%) with complex malformation syndromes and six (7%) with isolated extracardiac malformations. Seven cases (9%) had no associated condition. Eighty‐three percent of the fetuses in this series had associated cardiac malformations; the most frequent cardiac malformations in those with heterotaxy syndromes were complete atrioventricular septal defect (75%) and right outflow tract obstruction (58%). After exclusion of cases with heterotaxy, most congenital heart defects were ventricular septal defects (41%) and coarctation (34%). The outcome of PLSVC was determined solely by the associated conditions. After exclusion of terminated cases, heterotaxy syndromes as well as complete atrioventricular septal defects were associated significantly with perinatal and infant death. In contrast, all cases with isolated PLSVC or associated correctable extracardiac malformations survived and were doing well at the time of writing.

Conclusions

PLSVC detected in fetal life has to be followed by a meticulous inspection of the fetal anatomy as it is frequently associated with heterotaxy syndromes, other cardiac/non‐cardiac malformations and aneuploidy that determine the outcome. Isolated PLSVC is a benign vascular anomaly and may not affect the outcome. Copyright © 2006 ISUOG. Published by John Wiley & Sons, Ltd.
Prenatal detection of heart defects in a non‐selected population of 30 149 fetuses—detection rates and outcome
Authors: Tegnander E. , Williams W. , Johansen O. J. , Blaas H.‐G. K. , Eik‐Nes S. H.
Published: February 2006

Objectives

To evaluate the detection rate of congenital heart defects (CHD) in a non‐selected population and to follow outcome after diagnosis.

Methods

All 30 149 fetuses/newborns that were scheduled to deliver at our hospital between February 1991 and December 2001 were registered prospectively. Of these, 29 460 (98%) fetuses had a prenatal ultrasound scan at our center. The routine fetal examination at approximately 18 weeks' gestation included the four‐chamber view and the great arteries of the fetal heart. The follow‐up period was 2–13 years.

Results

Of 97 major CHDs, 55 (57%) were detected prenatally, 16% (9/55) prior to, 66% (36/55) at and 18% (10/55) after the routine scan. Forty‐four percent (19/43) of the isolated CHDs, 67% (36/54) of those with associated malformations and 48% (11/23) of the isolated ductal‐dependent CHDs were detected. Thirty‐eight percent (37/97) had an abnormal karyotype. Of the 55 major CHDs detected, 44% (24) of the pregnancies with lethal/serious fetal malformations were terminated, 15% (8) died in utero, 42% (23) were born alive and 27% (15) were still alive after 2 years. Of the 42 CHDs detected postnatally, 2% (1) were terminated for other reasons, 98% (41) were born alive and 81% (34) were still alive after 2 years.

Conclusions

Prenatal detection of CHD is still a challenge, with a 57% detection rate only. Isolated defects are detected less frequently. The overall outcome suggests that the most severe defects are detected with the present screening setting; only 27% of the babies with major CHDs detected were still alive after 2 years. Data from long‐term follow‐up will be of importance for the counseling process. Copyright © 2006 ISUOG. Published by John Wiley & Sons, Ltd.
Seasonality in neotropical populations of Plutella xylostella (Lepidoptera): resource availability and migration
Authors: Campos Wellington Garcia , Schoereder José H. , DeSouza Og F.
Published: February 2006

The present study aimed to verify (1) whether seasonal increases in neotropical populations of Plutella xylostella are directly provoked by regular influxes of migrants, and (2) whether temporal variation in food availability is the ecological process behind such predictable events. Over 3 years, plants that P. xylostella prefers were cultivated and irrigated in order to provide a continuous and abundant supply of food. Nevertheless, seasonal oscillations in the population of the herbivore still occurred. The hypothesis of seasonal availability of host plants could not explain the population pattern. In April, when the insect was practically extinct from the area, an artificial infestation (immigration) with 10,000 pupae established a precocious population. Therefore, the start of the natural cycles of population growth, during July–August, seems to be due to external factors, rather than an improvement in local conditions for resident individuals. In the beginning of the natural cycles, the increase in the density of adults significantly preceded the increase in immatures. Plutella xylostella does not diapause, and therefore immigration is the proximate cause of the seasonal population increases. Hypotheses about local factors are suggested to explain the decreasing phase of the predictable population cycles.
THE POLYNOMIAL NUMERICAL INDEX OF A BANACH SPACE
Authors: Choi Yun Sung , Garcia Domingo , Kim Sung Guen , Maestre Manuel
Published: February 2006

In this paper, we introduce the polynomial numerical index of order $k$ of a Banach space, generalizing to $k$-homogeneous polynomials the ‘classical’ numerical index defined by Lumer in the 1970s for linear operators. We also prove some results. Let $k$ be a positive integer. We then have the following:

(i) $n^{(k)}(C(K))=1$ for every scattered compact space $K$.

(ii) The inequality $n^{(k)}(E)\geq k^{k/(1-k)}$ for every complex Banach space $E$ and the constant $k^{k/(1-k)}$ is sharp.

(iii) The inequalities

$$ n^{(k)}(E)\leq n^{(k-1)}(E)\leq\frac{k^{(k+(1/(k-1)))}}{(k-1)^{k-1}}n^{(k)}(E) $$

for every Banach space $E$.

(iv) The relation between the polynomial numerical index of $c_0$, $l_1$, $l_{\infty}$ sums of Banach spaces and the infimum of the polynomial numerical indices of them.

(v) The relation between the polynomial numerical index of the space $C(K,E)$ and the polynomial numerical index of $E$.

(vi) The inequality $n^{(k)}(E^{**})\leq n^{(k)}(E)$ for every Banach space $E$.

Finally, some results about the numerical radius of multilinear maps and homogeneous polynomials on $C(K)$ and the disc algebra are given.
NORM ESTIMATES OF THE PRE-SCHWARZIAN DERIVATIVES FOR CERTAIN CLASSES OF UNIVALENT FUNCTIONS
Authors: Kim Yong Chan , Sugawa Toshiyuki
Published: February 2006

A sharp norm estimate will be given to the pre-Schwarzian derivatives of close-to-convex functions of specified type. In order to show the sharpness, we introduce a kind of maximal operator which may be of independent interest. We also discuss a relation between the subclasses of close-to-convex functions and the Hardy spaces.
SPECTRUM OF THE LAPLACIAN OF AN ASYMMETRIC FRACTAL GRAPH
Authors: Jordan Jonathan
Published: February 2006

We consider a simple self-similar sequence of graphs that does not satisfy the symmetry conditions that imply the existence of a spectral decimation property for the eigenvalues of the graph Laplacians. We show that, for this particular sequence, a very similar property to spectral decimation exists, and we obtain a complete description of the spectra of the graphs in the sequence.
THE NORM OF THE PRODUCT OF POLYNOMIALS IN INFINITE DIMENSIONS
Authors: Boyd C. , Ryan R. A.
Published: February 2006

Given a Banach space $E$ and positive integers $k$ and $l$ we investigate the smallest constant $C$ that satisfies $\|P\|\hskip1pt\|Q\|\le C\|PQ\|$ for all $k$-homogeneous polynomials $P$ and $l$-homogeneous polynomials $Q$ on $E$. Our estimates are obtained using multilinear maps, the principle of local reflexivity and ideas from the geometry of Banach spaces (type and uniform convexity). We also examine the analogous problem for general polynomials on Banach spaces.
LOW-REGULARITY SOLUTIONS FOR THE OSTROVSKY EQUATION
Authors: Huo Zhaohui , Jia Yueling
Published: February 2006

The well-posedness of the Ostrovsky equation is considered. Local well-posedness for data in $\tilde{H}^s(\mathbb{R})$ $(s\geq-\frac{1}{8})$ and global well-posedness for data in $\tilde{L}^{2}(\mathbb{R})$ are obtained.
LEGENDRIAN GRAPHS GENERATED BY TANGENTIAL FAMILY GERMS
Authors: Capitanio Gianmarco
Published: February 2006

We construct a Legendrian version of envelope theory. A tangential family is a one-parameter family of rays emanating tangentially from a regular plane curve. The Legendrian graph of the family is the union of the Legendrian lifts of the family curves in the projectivized cotangent bundle $PT^*\mathbb{R}^2$. We study the singularities of Legendrian graphs and their stability under small tangential deformations. We also find normal forms of their projections into the plane. This allows us to interpret the beak-to-beak perestroika as the apparent contour of a deformation of the double Whitney umbrella singularity $A_1^\pm$.
RIGIDITY OF HYPERSURFACES IN A EUCLIDEAN SPHERE
Authors: Wang Qiaoling , Xia Changyu
Published: February 2006

This paper studies topological and metric rigidity theorems for hypersurfaces in a Euclidean sphere. We first show that an $n({\geq}\,2)$-dimensional complete connected oriented closed hypersurface with non-vanishing Gauss–Kronecker curvature immersed in a Euclidean open hemisphere is diffeomorphic to a Euclidean $n$-sphere. We also show that an $n({\geq}\,2)$-dimensional complete connected orientable hypersurface immersed in a unit sphere $S^{n+1}$ whose Gauss image is contained in a closed geodesic ball of radius less than $\pi/2$ in $S^{n+1}$ is diffeomorphic to a sphere. Finally, we prove that an $n({\geq}\,2)$-dimensional connected closed orientable hypersurface in $S^{n+1}$ with constant scalar curvature greater than $n(n-1)$ and Gauss image contained in an open hemisphere is totally umbilic.
DIFFRACTIVE GEODESICS OF A POLYGONAL BILLIARD
Authors: Hillairet Luc
Published: February 2006

We define the notion of diffractive geodesic for a polygonal billiard or, more generally, for a Euclidean surface with conical singularities. We study the local geometry of the set of such geodesics of given length and we relate it to a number that we call classical complexity. This classical complexity is then computed for any diffractive geodesic. As an application we describe the set of periodic diffractive geodesics as well as the symplectic aspects of the ‘diffracted flow’.
A REMARK ON THE EXISTENCE OF BREATHER SOLUTIONS FOR THE DISCRETE NONLINEAR SCHRÖDINGER EQUATION IN INFINITE LATTICES: THE CASE OF SITE-DEPENDENT ANHARMONIC PARAMETERS
Authors: Karachalios Nikos I.
Published: February 2006

We discuss the existence of breather solutions for a discrete nonlinear Schrödinger equation in an infinite $N$-dimensional lattice, involving site-dependent anharmonic parameters. We give a simple proof of the existence of (non-trivial) breather solutions based on a variational approach, assuming that the sequence of anharmonic parameters is in an appropriate sequence space (decays with an appropriate rate). We also give a proof of the non-existence of (non-trivial) breather solutions, and discuss a possible physical interpretation of the restrictions, in both the existence and non-existence cases.
ON THE BEHAVIOUR OF EIGENVALUES ASSOCIATED WITH STURM–LIOUVILLE PROBLEMS ON SHRINKING DOMAINS
Authors: Needham D. J. , King A. C.
Published: February 2006

We establish results concerning the detailed asymptotic structure of the eigenvalues of a class of regular and singular Sturm–Liouville problems as the domain size shrinks to zero. This is motivated by the recent paper of Bailey et al. and provides an extensive generalization of the results therein.
MULTIPLE POSITIVE SOLUTIONS FOR A CRITICAL GROWTH PROBLEM WITH HARDY POTENTIAL
Authors: Han Pigong
Published: February 2006

In this paper we study the existence and nonexistence of multiple positive solutions for the Dirichlet problem:

$$ -\Delta{u}-\mu\frac{u}{|x|^2}=\lambda(1+u)^p,\quad u\gt0,\quad u\in H^1_0(\varOmega), \tag{*} $$

where $0\leq\mu\lt(\frac{1}{2}(N-2))^2$, $\lambda\gt0$, $1\ltp\leq(N+2)/(N-2)$, $N\geq3$. Using the sub–supersolution method and the variational approach, we prove that there exists a positive number $\lambda^*$ such that problem (*) possesses at least two positive solutions if $\lambda\in(0,\lambda^*)$, a unique positive solution if $\lambda=\lambda^*$, and no positive solution if $\lambda\in(\lambda^*,\infty)$.
ESTIMATES OF BLOW-UP TIME FOR A NON-LOCAL REACTIVE–CONVECTIVE PROBLEM MODELLING OHMIC HEATING OF FOODS
Authors: Nikolopoulos C. V. , Tzanetis D. E.
Published: February 2006

In this work, we estimate the blow-up time for the non-local hyperbolic equation of ohmic type, $u_t+u_{x}=\lambda f(u)/(\int_{0}^1f(u)\,\mathrm{d} x)^{2}$, together with initial and boundary conditions. It is known that, for $f(s)$, $-f'(s)$ positive and $\int_0^\infty f(s)\,\mathrm{d} s\lt\infty$, there exists a critical value of the parameter $\lambda>0$, say $\lambda^\ast$, such that for $\lambda>\lambda^\ast$ there is no stationary solution and the solution $u(x,t)$ blows up globally in finite time $t^\ast$, while for $\lambda\leq\lambda^\ast$ there exist stationary solutions. Moreover, the solution $u(x,t)$ also blows up for large enough initial data and $\lambda\leq\lambda^\ast$. Thus, estimates for $t^\ast$ were found either for $\lambda$ greater than the critical value $\lambda^\ast$ and fixed initial data $u_0(x)\geq0$, or for $u_0(x)$ greater than the greatest steady-state solution (denoted by $w_2\geq w^*$) and fixed $\lambda\leq\lambda^\ast$. The estimates are obtained by comparison, by asymptotic and by numerical methods. Finally, amongst the other results, for given $\lambda$, $\lambda^*$ and $0\lt\lambda-\lambda^*\ll1$, estimates of the following form were found: upper bound $\epsilon+c_1\ln[c_2(\lambda-\lambda^*)^{-1}]$; lower bound $c_3(\lambda-\lambda^*)^{-1/2}$; asymptotic estimate $t^\ast\sim c_4(\lambda-\lambda^\ast)^{-1/2}$ for $f(s)=\mathrm{e}^{-s}$. Moreover, for $0\lt\lambda\leq\lambda^*$ and given initial data $u_0(x)$ greater than the greatest steady-state solution $w_2(x)$, we have upper estimates: either $c_5\ln(c_6A^{-1}_0+1)$ or $\epsilon+c_7\ln(c_8\zeta^{-1})$, where $A_0$, $\zeta$ measure, in some sense, the difference $u_0-w_2$ (if $u_0\to w_2+$, then $A_0,\zeta\to0+$). $c_i\gt0$ are some constants and $0\lt\epsilon\ll1$, $0\ltA_0,\zeta$. Some numerical results are also given.
An application of Bayesian QTL mapping to early development in double haploid lines of rainbow trout including environmental effects
Authors: MARTINEZ VICTOR , THORGAARD GARY , ROBISON BARRIE , SILLANPÄÄ MIKKO J.
Published: February 2006

A Bayesian model and variable dimensional parameter estimation based on Markov chain Monte Carlo was applied to map quantitative trait loci (QTLs) in a doubled haploid mapping population of rainbow trout. To increase power, the analysis was performed using the multiple-QTL model, which simultaneously accounted for all the environmental and genetic main effects that influence the expression of early development life history traits. By doing so we obtained the posterior estimated effects for the environmental factors as well as the number, positions, and the effects for the QTLs. The analyses revealed QTLs for time at hatching, embryonic length and weight at swim-up stage. The posterior expectation of the number of QTLs in different linkage groups shows that at least four QTLs are needed to explain the observed differences in early development between the clonal lines. The Bayesian method effectively combined all the information available to accurately position these QTLs in the rainbow trout genome.
Abstracts of papers presented at the fifteenth Genetics Society's Mammalian Genetics and Development Workshop held at the Institute of Child Health, University College London on 22 and 23 November 2004
Authors: COPP ANDREW J. , FISHER ELIZABETH M. C.
Published: February 2006

The Transforming growth factor-β (TGF-β) family control diverse cellular processes and specify cell-fate/differentiation during embryogenesis in vertebrates and invertebrates. Mutations disrupting TGF-β signalling lead to developmental abnormalities and a range of diseases such as cancer. Nodal is a major TGF-β signal, responsible for gastrulation in embryogenesis. Arkadia (Akd) was discovered by mouse gene-trap mutagenesis and encodes a nuclear E3 ubiquitin ligase. Akd allows the Nodal signal to reach its maximum level and Akd-null mice lack mammalian organiser (MO) and mesendodermal tissues. Although Akd RNA is ubiquitously expressed, Akd-null mice lose a subset of Nodal-dependent functions. The specificity of Akd function is therefore most likely to be regulated post-transcriptionally or by co-factors. Akd possesses differentially spliced 5′ untranslated regions (UTRs) and large 3′ UTR. We have employed bioinformatics and developed a reporter system to address Akd post-transcriptional regulation. Akd RNA may initiate from different promoters and 5′ UTR differential splicing, upstream AUGs (uAUGs) and open-reading frames upstream (uORFs) may regulate protein translation. 5′ and 3′ UTRs can interact to either destabilise or decrease translational efficiency of RNA. The nature of this interaction is cell-type and signal level dependent. These data may represent mechanisms by which translational control of Arkadia is achieved and ultimately how TGF-β/Nodal signalling is regulated during embryogenesis.
Musiktherapie mit Paaren, bei denen die Frau an Krebs erkrankt ist
Authors: Körting Anna , Marmé Alexander , Verres Rolf , Stammer Heike
Published: February 2006

Zusammenfassung. An der Universitäts-Frauenklinik Heidelberg wurde seit März 2003 im Rahmen eines eintägigen Kommunikationsworkshops für Paare eine musiktherapeutische Interventionseinheit implementiert und evaluiert. Ziel der Intervention ist es, über aktives Musikmachen (Improvisation) mit dem Partner die Kommunikation der Paare anzuregen, Möglichkeiten der Förderung des körperlichen und seelischen Wohlbefindens bewusst zu machen und den Zusammenhalt des Paares zu stärken. Zur Erfassung der Fragestellung wurde eine fünfstufige Musiktherapie-Ratingskala zur Selbstbeurteilung der Paare entwickelt. Auf Grund des explorativen Charakters der Untersuchung wurden die Ergebnisse deskriptiv ausgewertet. An dem Workshop nahmen bisher 16 Paare teil. Sowohl die Männer als auch die Frauen erlebten beim gemeinsamen Spiel einen intensiveren Kontakt zu ihrem Partner und verspürten größere Nähe zu ihm. Darüber hinaus gaben die Paare an, Spaß beim Musik machen gehabt zu haben. Einiges deutet darauf hin, dass diese musiktherapeutische Intervention einen besonderen Beitrag für die Krankheitsbewältigung von Krebspatientinnen und deren Partnern leisten und somit das Spektrum psychosozialer Interventionen in der Psychoonkologie bereichern kann.
Analytische Betrachtung des Emotionsgehalts im Bewegungsmaterial im zeitgenössischen Tanz
Authors: Fäh Eugster Andrea
Published: February 2006

Zusammenfassung. Die vorliegende Arbeit untersucht den Emotionsgehalt im Bewegungsmaterial im zeitgenössischen Tanz am Beispiel des Solos “wer anders in mir“ und behandelt die Frage, inwieweit tänzerisches Material Emotionen authentisch ausdrücken kann. Die theoretische Abhandlung von Emotion und Körpersprache liefert die Basis dieser Studie. Der darauf aufbauende praktische Teil beinhaltet die Kreation des erwähnten Solos, das verschiedene Emotionen thematisiert. Die dabei gesammelten Erfahrungen werden in einem entsprechenden Bericht erläutert. Darüber hinaus liefert die Choreographie Bewegungssequenzen, die im Rahmen einer empirischen Studie auf ihre emotionale Authentizität untersucht werden und damit dem analytischen Teil der Arbeit entsprechen. Emotional authentisches Material begründet sich in seiner Reversibilität und damit in einem dynamischen Kreislauf: Die innere Bewegtheit löst eine Bewegung aus, die ihrerseits wiederum zur inneren Bewegtheit führt. Der Gefahr eines Informationsverlusts auf den Kommunikationswegen ChoreografIn/TänzerIn und TänzerIn/ZuschauerIn wirken die sorgfältige Bewegungsübermittlung bis hin zur Beherrschung der tänzerischen Materialität, eine geeignete psychische und physische Verfassung seitens TänzerIn und ZuschauerIn, Sensibilität und Offenheit gegenüber emotionalem Bewegungsmaterial sowie Empathie entgegen.
Die Zeichenspur als “Existenzaussage“
Authors: Wichelhaus Barbara
Published: February 2006

Zusammenfassung. Randphänomene unserer ästhetisch erfahrbaren Welt, wie der elementare bildnerische Ausdruck von Menschen im Zustand schwerer Lebenskrisen, bedürfen einer besonderen Betrachtungsweise. Es handelt sich dabei häufig um zeichnerische Äußerungen, die mit den Fingern oder einem Stift als Spuren auf einem Malgrund hinterlassen werden, Kritzeleien, die für den Betrachter keinerlei Analogien zu einem Gegenstand der erfahrbaren Außenwelt aufweisen und deshalb inkommensurabel scheinen. Bezieht man diese Zeichenspuren nicht auf ein externes außenweltliches Objekt sondern auf die Psyche des Produzenten, auf vor- und unbewusste Prozesse, dann können sie identifiziert werden, z.B. als “Abbilder“ von Emotionen und psychischen Konflikten, als expressiver Ausdruck einer inneren Bewegung oder als eine elementare Form der “Existenzaussage“.
“Davon geht die Welt nicht unter“ 1Unter dem Titel “Davon geht die Welt nicht unter - trotzige Zuversicht in trostloser Zeit?“ wurde die musikalische Zeitreise vorgetragen bei den Oberinntaler Diskursen zum Thema des Jahres 2005: “,... trotzdem: Zuversicht‘ - Perspektiven in einer Welt des Wandels“ ( www.oberinntaler-diskurse.fiss.at).
Authors: Hörmann Georg
Published: February 2006

Zusammenfassung. Das bekannte Lied “Davon geht die Welt nicht unter“ aus dem Film “Die Große Liebe“ (1942) gibt Anlass, die Rolle und Funktion von Filmmusik im Kontext ihrer Aufgabe nicht nur als Unterhaltungsmittel, sondern als nationales “Erziehungsmittel“ (Goebbels) zu reflektieren. Die “Große Liebe“ wird über die Abkehr von der “Neuen Liebe“ bis hin zur Zuwendung zu “großen Gefühlen“ in einer musikalischen Zeitreise anhand bekannter Songs zwischen Durchhaltewillen, Espakismusbedürfnissen, Traumwelten und Glückssehnsucht jenseits von Defätismus und Resignation illustriert. Zur ästhetischen Bearbeitung von Liebe, Leid, Kummer und Glückshoffnungen im pädagogisch-therapeutischen Setting wird mit praktischen Anregungen ermuntert.
Brownian drift‐diffusion model for evolution of droplet size distributions in turbulent clouds
Authors: McGraw Robert , Liu Yangang
Published: February 2006

Effects from turbulence‐induced fluctuations in water vapor saturation on cloud droplet growth are examined using a Brownian diffusion model. The model predicts diffusive broadening of the droplet size distribution, tempered by enhanced evaporation‐induced drift of droplets to smaller size from vapor depletion, and approach to a stationary condition (Weibull distribution) determined by the balance between size‐space diffusion and drift. Monte Carlo simulations of the approach to the stationary limit and of the distribution itself are presented and compared favorably with observation. A key turbulence parameter required by the kinetic potential theory of drizzle formation is estimated using the new results.
First results from a marine controlled‐source electromagnetic survey to detect gas hydrates offshore Oregon
Authors: Weitemeyer K. A. , Constable S. C. , Key K. W. , Behrens J. P.
Published: February 2006

Submarine gas hydrate is a hazard to drilling, a potential hydrocarbon resource, and has been implicated as a factor in both submarine slope stability and climate change. Bulk in situ electrical resistivities evaluated from electromagnetic surveys have the potential to provide an estimate of the total hydrate volume fraction more directly than by using seismic and well log data. We conducted a marine controlled‐source electromagnetic sounding at Hydrate Ridge, Oregon, USA, in August, 2004. Electromagnetic fields transmitted by a deep‐towed horizontal electric dipole source were measured by a linear array of 25 seafloor electromagnetic receivers, positioned 600 m apart to produce a dense coverage in the recorded electric field data. Results are presented in simple form by apparent resistivity pseudosections, which produce an approximate image of lateral resistivity variations across the study region. Resistivity values are consistent with those from well logs collected in the area and pseudosection features are correlated with seismic reflectors. Archie's Law, based on pseudosection apparent resistivities, predicts volumetric hydrate concentrations vary from 0–30% across the ridge.
Satellite data reveal the 3‐D moisture structure of Tropical Intraseasonal Oscillation and its coupling with underlying ocean
Authors: Fu Xiouhua , Wang Bin , Tao Li
Published: February 2006

The water‐vapor profiles obtained from the Atmospheric Infrared Sounder (AIRS) on Satellite Aqua are used to document the 3‐D moisture structure of the boreal‐summer Tropical Intraseasonal Oscillation (TISO) over the Indo‐western Pacific region. With the support of several other Satellite data sets, the interactions between the TISO and underlying ocean are also investigated. The AIRS data reveal much larger tropospheric moisture perturbations than those depicted in previous reanalysis and analysis data sets. It also reveals a drying Atmospheric Boundary Layer (ABL) below the TISO convection probably due to the associated downdrafts. Before the occurrence of TISO convection, both positive Sea Surface Temperature (SST) anomaly and ABL moistening are observed. Further analysis suggests that the positive SST anomaly is the major contributor to the ABL moistening through enhancing surface evaporation. Therefore, the intraseasonal SST anomaly could positively feed back to the atmosphere through moistening the boundary layer, destabilizing the troposphere, and contributing to the northeastward propagation of the TISO.
Using the current seasonal cycle to constrain snow albedo feedback in future climate change
Authors: Hall Alex , Qu Xin
Published: February 2006

Differences in simulations of climate feedbacks are sources of significant divergence in climate models' temperature response to anthropogenic forcing. Snow albedo feedback is particularly critical for climate change prediction in heavily‐populated northern hemisphere land masses. Here we show its strength in current models exhibits a factor‐of‐three spread. These large intermodel variations in feedback strength in climate change are nearly perfectly correlated with comparably large intermodel variations in feedback strength in the context of the seasonal cycle. Moreover, the feedback strength in the real seasonal cycle can be measured and compared to simulated values. These mostly fall outside the range of the observed estimate, suggesting many models have an unrealistic snow albedo feedback in the seasonal cycle context. Because of the tight correlation between simulated feedback strength in the seasonal cycle and climate change, eliminating the model errors in the seasonal cycle will lead directly to a reduction in the spread of feedback strength in climate change. Though this comparison to observations may put the models in an unduly harsh light because of uncertainties in the observed estimate that are difficult to quantify, our results map out a clear strategy for targeted observation of the seasonal cycle to reduce divergence in simulations of climate sensitivity.
Rapid and synchronous ice‐dynamic changes in East Greenland
Authors: Luckman Adrian , Murray Tavi , de Lange Remko , Hanna Edward
Published: February 2006

Two major outlet glaciers in East Greenland have suddenly begun to accelerate and retreat. The speeds of Kangerdlugssuaq and Helheim remained steady during the 1990s despite progressive and substantial thinning, but have abruptly increased within the last two years, more than doubling ice flux to the ocean. Had it been an isolated example, the comparable 1998 speed‐up of Jakobshavn Isbræ in West Greenland might have been explained simply by its chance retreat past a pinning point. Now that two further Greenland outlets have exhibited similar behavior, a common process seems likely. A remarkable correspondence in the inter‐annual patterns of speed and ice‐front variation between Kangerdlugssuaq and Helheim implies a significant sensitivity to regional environmental factors. The period of continued warming and thinning appears to have primed these glaciers for a step‐change in dynamics not included in current models. We should expect further Greenland outlet glaciers to follow suit.