bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bayesian spectral density approach for modal updating using ambient data
Authors: Katafygiotis Lambros S. , Yuen Ka‐Veng 
Published: August 2002

AbstractThe problem of identification of the modal parameters of a structural model using measured ambient response time histories is addressed. A Bayesian spectral density approach (BSDA) for modal updating is presented which uses the statistical properties of a spectral density estimator to obtain not only the optimal values of the updated modal parameters but also their associated uncertainties by calculating the posterior joint probability distribution of these parameters. Calculation of the uncertainties of the identified modal parameters is very important if one plans to proceed with the updating of a theoretical finite element model based on modal estimates. It is found that the updated PDF of the modal parameters can be well approximated by a Gaussian distribution centred at the optimal parameters at which the posterior PDF is maximized. Examples using simulated data are presented to illustrate the proposed method. Copyright © 2001 John Wiley & Sons, Ltd.
Base isolation for retrofitting historic buildings: Evaluation of seismic performance through experimental investigation
Authors: De Luca Antonello , Mele Elena , Molina Javier , Verzeletti Guido , Pinto Artur V. 
Published: August 2002

AbstractAn experimental test program on a full‐scale model representing a sub‐assemblage of the cloister facade of the Sao Vicente de Fora monastery, retrofitted through base isolation, has been recently carried out at the European Laboratory for Structural Assessment of the Joint Research Centre of the European Commission. In this paper an overview of the laboratory model and the experimental results is provided. In particular, firstly the test model is described, including the geometry and mechanical properties of the masonry specimen and the design of the isolation devices; then the testing method and the sub‐structuring of the isolation system are described and the seismic inputs adopted for the pseudo‐dynamic tests are defined. Finally, the experimental results are discussed and compared to the analogous results obtained on the ‘as is’, fixed‐base sub‐assemblage model. The implications of the test outcomes are emphasized and developments of this research line are presented. Copyright © 2001 John Wiley & Sons, Ltd.
Changes in sediment sources and floodplain deposition rates in the catchment of the River Tweed, Scotland, over the last 100 years: the impact of climate and land use change
Authors: Owens Philip N. , Walling Desmond E. 
Published: August 2002

AbstractEvidence from floodplain cores collected from three sites in the middle reaches of the Tweed basin in Scotland is used to reconstruct changes in sediment sources and overbank floodplain deposition rates over the last c. 100 years. Core chronologies and sedimentation rates are established using 137Cs and unsupported 210Pb measurements. The average sedimentation rates since 1963 range from 1·9 ± 0·2 to 2·2 ± 0·2 kg m−2 a−1 and are lower than the average rates for the period 1894/95 to 1963, which range from 2·7 ± 0·6 to 5·9 ± 0·9 kg m−2 a−1. There is also evidence of significant downcore variations in sediment source, defined in terms of both type (i.e. topsoil or channel bank/subsoil material) and spatial location (i.e. main geological/topographic zones). There is no clear link between the changes in overbank sedimentation rates and sediment sources and the trends shown by precipitation, weather pattern and river flow records over the past 100 years, suggesting that changes in climate alone cannot explain the downcore trends. Instead, the temporal changes in overbank sedimentation rates and sediment source appear to be linked more closely to changes in land use and land management over the past 100 years and, more particularly, the introduction of land drainage at the end of the 19th century, the rapid increase in afforestation since the 1940s and the post‐war conversion of grassland to arable land. Copyright © 2002 John Wiley & Sons, Ltd.
Fire retardance in polyamide‐6. The effects of red phosphorus and radiation‐induced cross‐links
Authors: Balabanovich A.I. , Levchik G.F. , Levchik S.V. , Schnabel W. 
Published: August 2002

AbstractRed phosphorus contained in non‐irradiated polyamide‐6 at concentrations up to 12.5 does not significantly improve the fire resistance of the polymer. It weakens the thermal stability of the polymer as reflected by a decrease in the onset temperature for mass loss from 407°C to 363°C, but causes char formation as indicated by mres=13 wt%, the non‐volatile residue at 600°C. Irradiation of polyamide‐6, loaded with red phosphorus, with 60Co‐γ‐rays generates intermolecular cross‐links resulting in an improved fire resistance. However, the absorbed dose necessary to achieve improvement is too high (>1 MGy) from a practical point of view. This inconvenience is overcome by applying triallyl cyanurate (TAC) as a cross‐linking promoter. Typically, polyamide‐6 containing 5 wt% TAC and 12.5 wt% red phosphorus exposed to a γ‐ray dose of 22 kGy yields a V‐0 rating (in the mode A UL 94 test) concurrently with a small increase in the onset temperature for mass loss and a drastic increase in the residue non‐volatile at 600°C. Copyright © 2002 John Wiley & Sons, Ltd.
The essential oils of Thymus migricus and T. fedtschenkoi var. handelii from Turkey
Authors: Başer K. Hüsnü Can , Demirci Betül , Kirimer Neş'e , Satil Fatih , Tümen Gülendam 
Published: August 2002

AbstractThe essential oils of Thymus migricus Klokov et Des.‐Shost. and T. fedtschenkoi Ronniger var. handelii (Ronniger) Jalas were obtained by hydrodistillation, and analysed by GC–MS. The main components in the essential oils were found to be carvacrol and thymol and linalool, respectively. Copyright © 2001 John Wiley & Sons, Ltd.
Analysis of the essential oil from aerial parts of Perovskia atriplicifolia Benth. at different stages of plant growth
Authors: Dabiri M. , Sefidkon F. 
Published: August 2002

AbstractThe essential oils were isolated by steam distillation from aerial parts of Perovskia atriplicifolia Benth. at three stages of growth (before flowering, at the beginning of flowering and at complete flowering). The oils were investigated by a combination of GC and GC–MS. Oil yields related to the three stages of plant growth were 1.69%, 1.60% and 1.64% w/w, respectively. Oil yields, related to the stage of complete flowering, were: for flower oil, 1.45% w/w; for leaf oil 1.47% w/w; and for stem oil 2.1% w/w. Forty‐eight components were characterized from the aerial parts, the major components at the complete flowering stage being 1,8‐cineole (20.74%), camphor (14.52%), limonene (8.58%), β‐caryophyllene (7.91%), α‐pinene (7.77%), α‐humulene (6.28%) and δ‐3‐carene (6.04%). At the flowering stage, 46 components were identified: in leaf oil, β‐caryophyllene (12.51%), 1,8‐cineole (11.70%), limonene (9.66%), α‐humulene (9.36%); in stem oil, 1,8‐cineole (15.64%), β‐caryophyllene (11.92%), camphor (11.63%), α‐humulene (9.55%), limonene (5.24%); and in flower oil 1,8‐cineole (19.52%), α‐pinene (13.97%), camphor (8.60%), β‐caryophyllene (8.36%) were the major constituents. Copyright © 2001 John Wiley & Sons, Ltd.
The effect of solutal undercooling on double‐diffusive convection and macrosegregation during binary alloy solidification: a numerical investigation
Authors: Chakraborty Suman , Dutta Pradip 
Published: August 2002

AbstractIn this paper, we present a macroscopic numerical model that is capable of capturing the interaction between the double‐diffusive convective field and a localized fluid flow on account of solutal undercooling during non‐equilibrium solidification of binary alloys. The model is essentially based on a fixed‐grid enthalpy based control volume approach. In the present model, microscopic features pertaining to non‐equilibrium effects on account of solutal undercooling are incorporated through the formulation of a modified partition‐coefficient. The effective partition‐coefficient is numerically modelled by means of a number of macroscopically observable parameters related to the solidifying domain. This feature has made the present treatment different from micro‐macro modelling of alloy solidification, which involves certain parameters that may not be macroscopically resolvable. Numerical simulations are performed for the case of two‐dimensional transient solidification of Pb–Sn alloys (both hypoeutectic and hypereutectic) in a rectangular cavity, employing the present model. The simulation results are also compared with the corresponding experimental results quoted in the literature, and the agreement is excellent. From the results, it can be concluded that non‐equilibrium effects on account of solutal undercooling result in a more enhanced macrosegregation. Copyright © 2002 John Wiley & Sons, Ltd.
A numerical model for the flooding and drying of irregular domains
Authors: Brufau P. , Vázquez‐Cendón M. E. , García‐Navarro P. 
Published: August 2002

AbstractA numerical technique for the modelling of shallow water flow in one and two dimensions is presented in this work along with the results obtained in different applications involving unsteady flows in complex geometries. A cell‐centred finite volume method based on Roe's approximate Riemann solver across the edges of both structured and unstructured cells is presented. The discretization of the bed slope source terms is done following an upwind approach. In some applications a problem arises when the flow propagates over adverse dry bed slopes, so a special procedure has been introduced to model the advancing front. It is shown that this modification reproduces exactly steady state of still water in configurations with strong variations in bed slope and contour. The applications presented are mainly related with unsteady flow problems. The scheme is capable of handling complex flow domains as will be shown in the simulations corresponding to the test cases that are going to be presented. Comparisons of experimental and numerical results are shown for some of the tests. Copyright © 2002 John Wiley & Sons, Ltd.
Gain of 1q and loss of 22 are the most common changes detected by comparative genomic hybridisation in paediatric ependymoma
Authors: Ward Samantha , Harding Brian , Wilkins Peter , Harkness William , Hayward Richard , Darling John L. , Thomas David G.T. , Warr Tracy 
Published: August 2002

AbstractEpendymomas are the third most common brain tumour in the paediatric population. Although cytogenetic and molecular analyses have pinpointed deletions of chromosomes 6q, 17, and 22 in a subset of tumours, definitive patterns of genetic aberrations have not been determined. In the present study, we analysed 40 ependymomas from paediatric patients for genomic loss or gain using comparative genomic hybridisation (CGH). Eighteen of the tumours (45%) had no detectable regions of imbalance. In the remaining cases, the most common copy number aberrations were loss of 22 (25% of tumours) and gain of 1q (20%). Three regions of high copy number amplification were noted at 1q24‐31 (three cases), 8q21‐23 (two cases), and 9p (one case). Although there was no association with the loss or gain of any chromosome arm or with benign versus anaplastic histologic characteristics, the incidence of gain of 7q and 9p and loss of 17 and 22 was significantly higher in recurrent versus primary tumours. This study has identified a number of chromosomal regions that may contain candidate genes involved in the development of different subgroups of ependymoma. © 2001 Wiley‐Liss, Inc.
The aryl hydrocarbon receptor (AhR) and its nuclear translocator (Arnt) are dispensable for normal mammary gland development but are required for fertility
Authors: Le Provost Fabienne , Riedlinger Gregory , Hee Yim Sun , Benedict Jamie , Gonzalez Frank J. , Flaws Jodi , Hennighausen Lothar 
Published: August 2002

AbstractSummary: The aryl hydrocarbon receptor (AhR) and its nuclear translocator (Arnt) are transcription factors that play a role in the detection of and adaptation to environmental signals. AhR‐null mice are viable but show impaired lactation. Deletion of the Arnt gene from the mouse genome results in embryonic lethality. To determine the role of Arnt in mammary development and function, we inactivated the Arnt gene in mammary epithelium using Cre‐loxP recombination. Inactivation of the Arnt gene during pregnancy did not disrupt alveolar development or the ability of dams to nurse their litters. In contrast, dams in which the Arnt gene had been inactivated during puberty and in ovaries were subfertile, exhibited retarded mammary development, and impaired mammary function. To distinguish defects autonomous to mammary epithelium from indirect effects controlled by ovarian hormones, we transplanted Arnt‐null and AhR‐null mammary epithelium into wild‐type mice and evaluated development after one pregnancy. Normal mammary structures were observed in the absence of Arnt and AhR, demonstrating that neither transcription factor is necessary for mammary development. genesis 32:231–239, 2002. © 2002 Wiley‐Liss, Inc.
Genotype by smoking interaction for leptin levels in the San Antonio family heart study
Authors: Martin Lisa J. , Cole Shelley A. , Hixson James E. , Mahaney Michael C. , Czerwinski Stefan A. , Almasy Laura , Blangero John , Comuzzie Anthony G. 
Published: August 2002

AbstractRecent studies reported a marked inverse effect of smoking on serum levels of leptin (an adipocyte derived protein), offering a possible explanation for variation in body weight between smokers and non‐smokers. The goal of this study was to examine the genetic architecture of the response to smoking in leptin levels using data from the San Antonio Family Heart Study. We employed a variance decomposition analysis using maximum likelihood methods to model genotype by smoking interactions for leptin levels, examined the impact of the exclusion of smokers in a subsequent linkage analysis, and incorporated the QTL identified in the linkage analysis in a model of genotype by smoking interaction. We found significant evidence (P = 0.001) for a genotype by smoking status interaction for serum leptin levels. In the subsequent linkage analysis with smokers excluded, we obtained a maximum LOD score of 3.1 (P = 0.00008) near D8S1102. Using this QTL in a model of genotype by smoking status interaction, we identified significant evidence for an interaction at this specific locus (P = 0.04). Given these results, we hypothesize that a quantitative trait locus in this vicinity of chromosome 8 may have a differential effect on the expression of leptin in smokers versus non‐smokers. Genet. Epidemiol. 22:105–115, 2002. © 2002 Wiley‐Liss, Inc.
Quantification of type I error probabilities for heterogeneity LOD scores
Authors: Abreu Paula C. , Hodge Susan E. , Greenberg David A. 
Published: August 2002

AbstractLocus heterogeneity is a major confounding factor in linkage analysis. When no prior knowledge of linkage exists, and one aims to detect linkage and heterogeneity simultaneously, classical distribution theory of log‐likelihood ratios does not hold. Despite some theoretical work on this problem, no generally accepted practical guidelines exist. Nor has anyone rigorously examined the combined effect of testing for linkage and heterogeneity and simultaneously maximizing over two genetic models (dominant, recessive). The effect of linkage phase represents another uninvestigated issue. Using computer simulation, we investigated type I error (P value) of the “admixture” heterogeneity LOD (HLOD) score, i.e., the LOD score maximized over both recombination fraction θ and admixture parameter α and we compared this with the P values when one maximizes only with respect to θ (i.e., the standard LOD score). We generated datasets of phase‐known and ‐unknown nuclear families, sizes k = 2, 4, and 6 children, under fully penetrant autosomal dominant inheritance. We analyzed these datasets (1) assuming a single genetic model, and maximizing the HLOD over θ and α; and (2) maximizing the HLOD additionally over two dominance models (dominant vs. recessive), then subtracting a 0.3 correction. For both (1) and (2), P values increased with family size k; rose less for phase‐unknown families than for phase‐known ones, with the former approaching the latter as k increased; and did not exceed the one‐sided mixture distribution ξ = (½) χ + (½) χ. Thus, maximizing the HLOD over θ and α appears to add considerably less than an additional degree of freedom to the associated χ distribution. We conclude with practical guidelines for linkage investigators. Genet. Epidemiol. 22:156–169, 2002. © 2002 Wiley‐Liss, Inc.
Causes of variation in crystal morphology in metamorphogenic pyrite deposits of the Cameros Basin (N Spain)
Authors: Alonso‐Azcárate J. , Rodas M. , Fernández‐Díaz L. , Bottrell S.H. , Mas J. R. , López‐Andrés S. 
Published: August 2002

AbstractThe low‐grade metasediments of the Cameros Basin, northern Spain, host a number of deposits of spectacular quality pyrite mineralization. These formed during regional metamorphism and the pyrite crystals exhibit a wide range of morphologies. On the basis of pyrite crystal habit, the deposits can be classified into two groups: Group I comprises deposits with cubic, elongated or platy crystals; Group II comprises deposits characterized by pyritohedra and cubo‐pyritohedra with striated faces, along with blocky crystals and fine‐grained aggregates. Group I deposits are formed in sequences dominated by meandriform fluviatile sediments, while Group II is hosted by deltaic plain and lacustrine metasediments.Temperature differences between deposits and As content are possible causes of the different pyrite morphologies in the deposits, but no significant variation exists between the two groups for either factor. Comparison with experimentally grown pyrite crystals suggests that Group I deposits have morphologies indicative of lower degrees of pyrite supersaturation than pyrite crystals in Group II deposits. The sedimentary facies hosting Group II deposits provides a greater availability of sedimentary sulphur (pyrite and sulphates). Moreover, reactions involving sulphate during metamorphism may have modified fluid chemistry, which would also act to produce higher degrees of pyrite saturation in fluids derived from the sulphate‐rich deltaic plain and lacustrine metasediments hosting the Group II deposits. This hypothesis is confirmed by sulphur isotope data on the pyrites, which show a larger component of34S‐enriched sulphate‐derived sulphur in these deposits. Copyright © 2001 John Wiley & Sons, Ltd.
Immune function of astrocytes
Authors: Dong Yuanshu , Benveniste Etty N. 
Published: August 2002

AbstractAstrocytes are the major glial cell within the central nervous system (CNS) and have a number of important physiological properties related to CNS homeostasis. The aspect of astrocyte biology addressed in this review article is the astrocyte as an immunocompetent cell within the brain. The capacity of astrocytes to express class II major histocompatibility complex (MHC) antigens and costimulatory molecules (B7 and CD40) that are critical for antigen presentation and T‐cell activation are discussed. The functional role of astrocytes as immune effector cells and how this may influence aspects of inflammation and immune reactivity within the brain follows, emphasizing the involvement of astrocytes in promoting Th2 responses. The ability of astrocytes to produce a wide array of chemokines and cytokines is discussed, with an emphasis on the immunological properties of these mediators. The significance of astrocytic antigen presentation and chemokine/cytokine production to neurological diseases with an immunological component is described. GLIA 36:180–190, 2001. © 2001 Wiley‐Liss, Inc.
To tell or not to tell—comparison of older patients' reaction to their diagnosis of dementia and depression
Authors: Jha Arun , Tabet Naji , Orrell Martin 
Published: August 2002

AbstractObjectiveInvestigation of the reaction of elderly patients to the disclosure of their diagnosis of dementia compared with depression.DesignElderly patients suffering from dementia and depression were asked to complete a questionnaire about the diagnosis and other aspects of their clinical summary sent to them by post. Demographic data included age, gender, marital status and occupation; degree of dementia or depression was established by administering the mini‐mental state examination and the geriatric depression scale, respectively.SettingPatients were consecutive attendees of outpatient clinics (old age psychiatry) located in two suburban areas near London.MeasuresDemographic data included age, gender, marital status and occupation; degree of dementia or depression was established by administering the mini‐mental state examination and the geriatric depression scale, respectively.ResultsOne hundred cases were recruited, 53 with dementia and 47 with depression. Most depressed and dementia patients ( > 75%) liked the idea of reading their diagnosis but 25% of dementia cases felt upset. Within the dementia group, the majority of patients with mild or severe dementia welcomed the idea of knowing their diagnosis; and 13 (100%) of the patients with vascular dementia wished to know (compared with 68% cases with Alzheimer's disease). None felt upset, and only 39% of them felt pessimistic after reading their own clinical summary. However, among dementia patients who also happened to be depressed, a higher proportion (60%) expressed an unfavourable view towards knowing their diagnosis, but only a minority (40%) of them were actually upset. Most older married females, especially those with depression and Alzheimer's disease, felt pessimistic afterwards.ConclusionsThere was no significant difference between patients with dementia or depression in their wish to know their diagnosis. Patients with severe dementia, even if they felt upset, preferred to be told their diagnosis. Patients with vascular dementia tended to express a more favourable view. Copyright © 2001 John Wiley & Sons, Ltd.
Death and dementia
Authors: Keene Janet , Hope Tony , Fairburn Christopher G. , Jacoby Robin 
Published: August 2002

AbstractObjectiveTo investigate the last phase of dementia and the causes of death; comparing autopsy and death certificate diagnoses.DesignProspective, 11‐year, longitudinal study of behavioural and psychological changes in dementia, with autopsy follow‐up.SettingParticipants with dementia, living at home with a carer. All lived in Oxfordshire, UK.ParticipantsNinety‐one people with dementia (Alzheimer's disease and/or vascular dementia) who died during the course of the study.MeasuresAt four‐monthly intervals, carers were interviewed about the participants' behaviour using the Present Behavioural Examination. Participants were also assessed cognitively. Causes of death were established from death certificates and, where possible, from post‐mortem examination.ResultsThe main immediate cause of death recorded at autopsy was pneumonia (57%), followed by cardiovascular disease (16%) and pulmonary embolus (14%). This agreed with the immediate cause of death on 53% of death certificates. Pulmonary embolism and bronchopneumonia were under‐reported on death certificates. Dementia was mentioned on 73% of death certificates. The dementing illness lasted for a mean of 8.5 years with 58% dying in a debilitated state associated with severe dementia. In the period before death, 35% were unable to walk, 58% were hypophagic, 73% were incontinent of urine, 21% incontinent of faeces and 76% entered an institution permanently for a mean period of 18 months.ConclusionFamily and professional carers of people with dementia can be given some information about prognosis to help them plan for the likely outcome of dementia. Copyright © 2001 John Wiley & Sons, Ltd.