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Selected AbstractsA low-dimensional physically based model of hydrologic control of shallow landsliding on complex hillslopesEARTH SURFACE PROCESSES AND LANDFORMS, Issue 13 2008Ali Talebi Abstract Hillslopes have complex three-dimensional shapes that are characterized by their plan shape, profile curvature of surface and bedrock, and soil depth. To investigate the stability of complex hillslopes (with different slope curvatures and plan shapes), we combine the hillslope-storage Boussinesq (HSB) model with the infinite slope stability method. The HSB model is based on the continuity and Darcy equations expressed in terms of storage along the hillslope. Solutions of the HSB equation account explicitly for plan shape by introducing the hillslope width function and for profile curvature through the bedrock slope angle and the hillslope soil depth function. The presented model is composed of three parts: a topography model conceptualizing three-dimensional soil mantled landscapes, a dynamic hydrology model for shallow subsurface flow and water table depth (HSB model) and an infinite slope stability method based on the Mohr,Coulomb failure law. The resulting hillslope-storage Boussinesq stability model (HSB-SM) is able to simulate rain-induced shallow landsliding on hillslopes with non-constant bedrock slope and non-parallel plan shape. We apply the model to nine characteristic hillslope types with three different profile curvatures (concave, straight, convex) and three different plan shapes (convergent, parallel, divergent). In the presented model, the unsaturated storage has been calculated based on the unit head gradient assumption. To relax this assumption and to investigate the effect of neglecting the variations of unsaturated storage on the assessment of slope stability in the transient case, we also combine a coupled model of saturated and unsaturated storage and the infinite slope stability method. The results show that the variations of the unsaturated zone storage do not play a critical role in hillslope stability. Therefore, it can be concluded that the presented dynamic slope stability model (HSB-SM) can be used safely for slope stability analysis on complex hillslopes. Our results show that after a certain period of rainfall the convergent hillslopes with concave and straight profiles become unstable more quickly than others, whilst divergent convex hillslopes remain stable (even after intense rainfall). In addition, the relation between subsurface flow and hillslope stability has been investigated. Our analyses show that the minimum safety factor (FS) occurs when the rate of subsurface flow is a maximum. In fact, by increasing the subsurface flow, stability decreases for all hillslope shapes. Copyright © 2008 John Wiley & Sons, Ltd. [source] The relationship between host selection behaviour and offspring fitness in a koinobiont parasitoidECOLOGICAL ENTOMOLOGY, Issue 4 2000Ana Rivero Summary 1. When host quality varies, optimal foraging theory assumes that parasitic wasps select hosts in a manner that increases their individual fitness. In koinobiont parasitoids, where the hosts continue developing for a certain period of time after parasitisation, host selection may not reflect current host quality but may be based on an assessment of future growth rates and resources available for the developing larvae. 2. When presented with hosts of uniform quality, the koinobiont parasitoid Leptomastix dactylopii exhibits a characteristic host-selection behaviour: some hosts are accepted for oviposition on first encounter, while others are rejected several times before an egg is laid in them, a behaviour that is commonly associated with a changing host acceptance threshold during the course of a foraging bout. 3. The fitness of the offspring that emerged from hosts accepted immediately upon encounter was compared with the fitness of offspring emerged from hosts rejected several times before being accepted for oviposition. 4. The pattern of host acceptance and rejection was not related to any of the measured fitness parameters of the offspring emerging from these hosts (development time, size at emergence, sex ratio at emergence, and female offspring egg load). 5. While complex post facto adaptive explanations can be devised to explain the nature of such a time and energy consuming host selection process, it is suggested that physiological constraints on egg production or oviposition may provide an alternative, purely mechanistic, explanation for the results obtained. [source] Identification and quantification of in vitro adduct formation between protein reactive xenobiotics and a lysine-containing model peptideENVIRONMENTAL TOXICOLOGY, Issue 1 2003Peter Reichardt Abstract Formation of in vitro adducts between different classes of xenobiotics and the lysine-containing peptide Lys-Tyr was monitored by high-performance liquid chromatography and electrospray ionization mass spectrometry. The molecular structures of the main resulting products could be sensitively analyzed by mass spectrometry (flow injection analysis), enabling the detection of characteristic binding formations. Aldehydes such as formaldehyde, acetaldehyde, and benzaldehyde were shown to form stable linkages to lysine amino groups via Schiff bases. Other electrophilic substances (e.g., toluene-2,4-diisocyanate, 2,4-dinitro-1-fluorobenzene, 2,4,6-trinitrobenzene sulfonic acid, dansyl chloride, and phthalic acid anhydride) also formed covalent adducts with lysine residues. The reactivity of the compounds was quantified by measuring the amount of peptide that remained unchanged after incubation for a certain period with the xenobiotic. Although reactivity levels within this group of aldehydes varied only to a small extent, as would be expected, extreme differences were seen among the structurally heterogeneous group of nonaldehyde xenobiotics. These results support the hypothesis that simple chemical reactions may lead to the adduction of nucleophilic macromolecules such as peptides or proteins. Such reactions, in particular, Schiff base formation of aldehydes, have previously been shown to be capable of specifically interfering with costimulatory signaling on T cells. Our results suggest that electrophilic xenobiotics of other classes may also inherit the capacity to exert similar effects. Forming covalent linkage to peptides may represent a possible molecular mechanism of electrophilic xenobiotics in vivo, yielding immunotoxic effects. The model utilized in this study is appropriate for monitoring the adduction of xenobiotics to basic peptides and for analyzing the resulting molecular structures. © 2003 Wiley Periodicals, Inc. Environ Toxicol 18: 29,36, 2003. [source] Archaeological evidence for destructive earthquakes in Sicily between 400 B.C. and A.D. 600GEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 2 2009Carla Bottari A systematic archaeoseismological study indicates that at least three earthquakes occurred between 400 B.C. and A.D. 600, causing destruction to numerous ancient monuments in Sicily. Evidence for these earthquakes comes from the collapse style of buildings (toppled walls, column drums in a domino-style arrangement, directional collapses, etc.), and the exclusion of other likely causes for such effects. Dating of inferred earthquakes is based on coins (accurate to within 5,10 years), pottery (accurate to within 50,200 years), and other artifacts. The oldest documented earthquake occurred between 370 and 300 B.C. and caused the collapse of two Greek temples in Selinunte. This otherwise poorly documented event was probably also the cause of extensive destruction in northeastern Sicily in the first century A.D. Destruction of some sites may be assigned to an earthquake that occurred between 360 and 374 and correlates with the A.D. 365 seismic sequence known from historical sources. This study covers a wider region and provides a more precise dating of earthquakes than previous studies. Although it focuses on a certain period (4th,3rd centuries B.C., 4th,7th centuries A.D.), it indicates that the period before A.D. 1000 is not a period of seismic quiescence in Sicily as was previously believed, but to a period characterized by strong and destructive earthquakes. © 2009 Wiley Periodicals, Inc. [source] The maximum principle violations of the mixed-hybrid finite-element method applied to diffusion equationsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 12 2002H. Hoteit Abstract The abundant literature of finite-element methods applied to linear parabolic problems, generally, produces numerical procedures with satisfactory properties. However, some initial,boundary value problems may cause large gradients at some points and consequently jumps in the solution that usually needs a certain period of time to become more and more smooth. This intuitive fact of the diffusion process necessitates, when applying numerical methods, varying the mesh size (in time and space) according to the smoothness of the solution. In this work, the numerical behaviour of the time-dependent solutions for such problems during small time duration obtained by using a non-conforming mixed-hybrid finite-element method (MHFEM) is investigated. Numerical comparisons with the standard Galerkin finite element (FE) as well as the finite-difference (FD) methods are checked. Owing to the fact that the mixed methods violate the discrete maximum principle, some numerical experiments showed that the MHFEM leads sometimes to non-physical peaks in the solution. A diffusivity criterion relating the mesh steps for an artificial initial,boundary value problem will be presented. One of the propositions given to avoid any non-physical oscillations is to use the mass-lumping techniques. Copyright © 2002 John Wiley & Sons, Ltd. [source] Lyme borreliosis , an updateJOURNAL DER DEUTSCHEN DERMATOLOGISCHEN GESELLSCHAFT, Issue 5 2007Elisabeth Aberer Summary Lyme borreliosis is the most common tick-borne, infectious disease in the northern hemisphere. Disease manifestations in the United States and Europe vary as a result of geographic distribution of different species within the genospecies Borrelia burgdorferi sensu lato, which in turn are host-specific. Certain toxigenic B. burgdorferi strains cause early disseminated disease. The ability of Borrelial organisms to break down the extracellular matrix also promotes dissemination. B. burgdorferi are eliminated by complement-mediated lysis and by T and B cell activity of the specific immune response. Yet, B. burgdorferi can evade humoral immunity by means of type of protective mechanism by which it adheres to the proteoglycan decorin in the joints and skin. A further factor in the persistence of the pathogen is altered antigen expression. Re-infection usually occurs with a different strain, although repeated infection with the same strain is also possible after a certain period of latency. New developments in serologic testing include the use of recombinant native antigen as well as antigens produced in vivo such as VlsE (variable major protein-like sequence, expressed) or decorin-binding protein A. Diagnosis continues to be complicated by seropositivity of healthy individuals, the persistence of antibodies after therapy, and a lacking humoral immune response in patients with erythema migrans. [source] Experimental solar spectral irradiance until 2500,nm: results and influence on the PV conversion of different materialsPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 4 2007J. J. Pérez-López Abstract In this work, results are presented concerning solar spectral irradiance measurements performed in Madrid in the wavelength range 250,2500,nm, that is, extending the spectral range far away from the wavelengths where PV semiconductors are active. These data were obtained considering a horizontal receiver surface during selected clear days covering the four seasons of the year. PV materials having different spectral responses (m-Si, a-Si, CIGS, CdTe) have been considered to calculate spectral factors (SF) taking as reference the standard solar spectrum AM1.5 defined in standard IEC 60904-3. From these SFs, the influence of natural solar spectral variations in PV conversion has been established. It is shown, for example, that PV technologies based on a-Si are highly favored, from the spectral point of view, in spring,summer compared to other technologies having broader spectral responses, which are more favored in autumn,winter. From the experimental measured solar spectra, we have calculated Weighed Solar Spectra (WSS) corresponding to the four seasons of the year and also to the whole year. The WSS represents, for a certain period of time, the solar spectrum weighed over the irradiance level. SFs have been calculated for different WSSs showing spectral gains for the four PV materials during almost the full year. Otherwise, it is also shown in this work how the near-IR part of the solar spectrum affects the evaluation of the solar resource as a whole when reference solar cells made of different PV materials are used. For typical m-Si, a-Si, CIGS, and CdTe solar cells, the ratio of Isc over global irradiance is not constant along a given day showing variations that depend on the season and on the PV material considered. © 2006 John Wiley & Sons, Ltd. [source] Variability of sleep parameters across multiple laboratory sessions in healthy young subjects: The "very first night effect"PSYCHOPHYSIOLOGY, Issue 4 2002José-Luis Lorenzo Many studies have been carried out to assess the variability of sleep parameters. The first night effect is one of the most important factors in this variability and has been extensively studied. However, the readaptation phenomenon when subjects returned to the sleep laboratory after spending a certain period of time at home has been not systematically evaluated. To investigate this phenomenon across multiple sleep laboratory sessions, polysomnographic data from 12 healthy young subjects for 12 nights (three periods each of 4 consecutive nights, with a minimum of 1 month between them) were collected. The first night effect was present only in the first night of the first period ("very first night") and was significant only for REM sleep-related variables. We conclude that the results from the first nights of consecutive periods within a specific protocol with healthy young subjects need not be discarded in subsequent analyses. [source] Doubly adaptive biased coin designs with delayed responsesTHE CANADIAN JOURNAL OF STATISTICS, Issue 4 2008Feifang Hu Abstract In clinical studies, patients are usually accrued sequentially. Response-adaptive designs are then useful tools for assigning treatments to incoming patients as a function of the treatment responses observed thus far. In this regard, doubly adaptive biased coin designs have advantageous properties under the assumption that their responses can be obtained immediately after testing. However, it is a common occurrence that responses are observed only after a certain period of time. The authors examine the effect of delayed responses on doubly adaptive biased coin designs and derive some of their asymptotic properties. It turns out that these designs are relatively insensitive to delayed responses under widely satisfied conditions. This is illustrated with a simulation study. Plans aléatoires non équilibrés doublement adaptatifs avec délais de réponse Dans les études cliniques, les patients arrivent souvent séquentiellement. Aussi souhaite-t-on disposer de plans adaptatifs permettant d'assigner des traitements aux nouveaux patients au vu des résultats observés jusque-là. À cet égard, les plans aléatoires non équilibrés doublement adaptatifs sont avantageux dans la mesure où un test permet d'observer sans délai l'effet d'un traitement. Toutefois, il arrive aussi qu'un traitement ne fasse effet qu'après un temps. Les auteurs examinent les répercussions de tels délais sur les plans aléatoires non équilibrés doublement adaptatifs, dont ils dégagent certaines propriétés asymptotiques. Il s'avère que sous des conditions assez générales, ces plans sont plutôt insensibles aux délais. Une étude de simulation illustre le propos. [source] Assimilation of SEVIRI infrared radiances with HIRLAM 4D-VarTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 645 2009M. Stengel Abstract Four-dimensional variational data assimilation (4D-Var) systems are ideally suited to obtain the best possible initial model state by utilizing information about the dynamical evolution of the atmospheric state from observations, such as satellite measurements, distributed over a certain period of time. In recent years, 4D-Var systems have been developed for several global and limited-area models. At the same time, spatially and temporally highly resolved satellite observations, as for example performed by the Spinning Enhanced Visible and InfraRed Imager (SEVIRI) on board the Meteosat Second Generation satellites, have become available. Here we demonstrate the benefit of a regional NWP model's analyses and forecasts gained by the assimilation of those radiances. The 4D-Var system of the HIgh Resolution Limited Area Model (HIRLAM) has been adjusted to utilize three of SEVIRI's infrared channels (located around 6.2 µm, 7.3 µm, and 13.4 µm, respectively) under clear-sky and low-level cloud conditions. Extended assimilation and forecast experiments show that the main direct impact of assimilated SEVIRI radiances on the atmospheric analysis were additional tropospheric humidity and wind increments. Forecast verification reveals a positive impact for almost all upper-air variables throughout the troposphere. Largest improvements are found for humidity and geopotential height in the middle troposphere. The observations in regions of low-level clouds provide especially beneficial information to the NWP system, which highlights the importance of satellite observations in cloudy areas for further improvements in the accuracy of weather forecasts. Copyright © 2009 Royal Meteorological Society [source] Do Controlling Shareholders Manage the Timing of Information Disclosure When Making a Stock Gift?,ASIA-PACIFIC JOURNAL OF FINANCIAL STUDIES, Issue 6 2009Woon-Oh Jung Abstract In Korea, controlling shareholders in general tend to transfer their shares to their family members or related parties. In this paper, we investigate whether Korean controlling shareholders attempt to influence stock prices by managing the timing of information disclosures when they transfer stocks to related parties as gifts. Because gift taxes are levied based on the average market value of the stock transferred for a certain period known as the valuation period, controlling shareholders may have incentives to depress the stock prices in this period in order to reduce the gift tax. We make a specific conjecture that controlling shareholders may wish to time the disclosure of good news and bad news so that the latter (the former) is released during (outside of) the valuation period for the stock to be transferred. To test this hypothesis we examine the disclosure timing of good and bad news for a sample of 118 gift transactions by 83 firms over the period of 2000,2004. We find that during the valuation period (i.e., the 4-month period extending over the 2 months before and after the gift transaction) the frequency of good news was considerably lower than in other periods, whereas the frequency of bad news during the valuation period was substantially higher. This result supports the hypothesis that controlling shareholders may delay good news and bring forward bad news in an attempt to influence stock prices during the valuation period. Despite the attempts by controlling shareholders to keep stock prices depressed in the valuation period, we also find that the prices tend to increase after the gift announcement date. We provide some of the potential explanations for the upward price movement subsequent to gift transactions. [source] Past Times: Temporal Structuring of History and MemoryETHOS, Issue 2 2006Kevin Birth In On Collective Memory, Maurice Halbwachs asks, "Why does society establish landmarks in time that are placed close together,and usually in a very irregular manner, since for certain periods they are almost entirely lacking,whereas around such salient events sometimes many other equally salient events seem to gather, just as street signs and other signposts multiply as a tourist attraction approaches?" (1992:175). The recognition of the "irregular manner" of history and memory only emerges in contrast to a concept of the regularity of time implied by objectifying chronologies. Furthermore, such irregularity suggests that concepts of time other than chronology are crucial for understanding representations of the past, and experiences of the past in the present. This article draws on nondirected interviews conducted in rural Trinidad in which subjects discussed significant events in their lives. In examining this material, I address Halbwachs's question by emphasizing nonchronological, cultural models of time that organize autobiographical narratives. These cultural models position autobiographical narratives in space and connect them to events of historical significance. [time, memory, intersubjectivity, labor, Trinidad] [source] Regularized Intergovernmentalism: France,Germany and Beyond (1963,2009)FOREIGN POLICY ANALYSIS, Issue 2 2010Ulrich Krotz Regularized intergovernmentalism refers to a distinct kind of foreign policy practice that connects and intertwines foreign policy processes in particular ways. This paper puts forth a concept to properly capture and expose such distinctive foreign policy realities characterizing certain periods and places. With this concept, the article systematically scrutinizes the intergovernmental fabric of bilateral Franco,German relations from 1963 to 2009. The characteristic features of Franco,German regularized intergovernmentalism represent a crucial foreign policy connection, foundational for European affairs of the past half century and a defining feature of Europe's post-war order and regional governance. Exploring key aspects of what it is that links France and Germany in particular ways, this paper offers a historically deeply grounded constitutive analysis. Based on its constitutive inquiries, the papers points at new possibilities of causal theorizing and explores some of regularized intergovernmentalism's hypothesized effects and limitations. Franco,German intergovernmental affairs may be the most developed instance of this practice. But regularized bilateral intergovernmentalism is not a Franco,German idiosyncrasy. Rather, it is an important and apparently growing approach to structuring foreign policy conduct, and seems an increasingly prominent aspect of how the world is organized. [source] Water-Yield Reduction After Afforestation and Related Processes in the Semiarid Liupan Mountains, Northwest China,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 5 2008Yanhui Wang Abstract:, The increase of coverage of forest/vegetation is imperative to improve the environment in dry-land areas of China, especially for protecting soil against serious erosion and sandstorms. However, inherent severe water shortages, drought stresses, and increasing water use competition greatly restrict the reforestation. Notably, the water-yield reduction after afforestation generates intense debate about the correct approach to afforestation and forest management in dry-land areas. However, most studies on water-yield reduction of forests have been at catchment scales, and there are few studies of the response of total evapotranspiration (ET) and its partitioning to vegetation structure change. This motivates us to learn the linkage between hydrological processes and vegetation structure in slope ecosystems. Therefore, an ecohydrological study was carried out by measuring the individual items of water balance on sloping plots covered by different vegetation types in the semiarid Liupan Mountains of northwest China. The ratio of precipitation consumed as ET was about 60% for grassland, 93% for shrubs, and >95% for forestland. Thus, the water yield was very low, site-specific, and sensitive to vegetation change. Conversion of grassland to forest decreased the annual water yield from slope by 50-100 mm. In certain periods, the plantations at lower slopes even consumed the runon from upper slopes. Reducing the density of forests and shrubs by thinning was not an efficient approach to minimize water use. Leaf area index was a better indicator than plant density to relate ET to vegetation structure and to evaluate the soil water carrying capacity for vegetation (i.e., the maximum amount of vegetation that can be supported by the available soil water for an extended time). Selecting proper vegetation types and plant species, based on site soil water condition, may be more effective than the forest density regulation to minimize water-yield reduction by vegetation coverage increase and notably by reforestation. Finally, the focuses in future research to improve the forest-water relations in dry-land areas are recommended as follows: vegetation growth dynamics driven by environment especially water conditions, coupling of ecological and hydrological processes, further development of distributed ecohydrological models, quantitative relation of eco-water quota of ecosystems with vegetation structures, multi-scaled evaluation of soil water carrying capacity for vegetation, and the development of widely applicable decision support tools. [source] Estimating species' absence, colonization and local extinction in patchy landscapes: an application of occupancy models with rodentsJOURNAL OF ZOOLOGY, Issue 3 2007A. Mortelliti Abstract Making an inference on the absence of a species in a site is often problematic, due to detection probability being, in most cases, <1. Inference is more complicated if detection probability, together with distribution patterns, vary during the year, since the possibility of inferring a species absence, at reasonable costs, may be possible only in certain periods. Our aim here is to show how such challenging situations can be by tackled by applying some recently developed occupancy models combined with sample size (number of repeated surveys) estimation. We thus analysed the distribution of two rodents Myodes glareolus and Mus musculus domesticus in a fragmented landscape in central Italy pointing out how it is possible to identify true absences, non-detections, extinctions/colonizations and determine seasonal values of detection probability. [source] Gabbroic clay sources in Cornwall: a petrographic study of prehistoric pottery and clay samplesOXFORD JOURNAL OF ARCHAEOLOGY, Issue 3 2004Lucy Harrad Summary., This analysis of prehistoric pottery and clay samples from Cornwall demonstrates that the clay used to make Cornish gabbroic pottery in prehistory originated around the gabbro rock outcrop in a small area of the Lizard peninsula. The research uses petrographic and chemical analysis to subdivide the prehistoric pottery into six groups. Owing to the unusual geology of the Lizard these groups can be attributed to specific locations. The most abundant pottery fabric, Typical Gabbroic, was made using coarse clay which is mainly found in a 1 km2 area near Zoar. A finer version of this clay, found higher in the soil profile or slightly transported and redeposited, was used to make Fine Gabbroic pottery and an even finer variant called FNS (Fine Non-Sandy) Gabbroic. We identify for the first time here a Loessic/Gabbroic pottery fabric which can be matched exactly to clay found at Lowland Point. Serpentinitic/Gabbroic pottery was made using clay from the gabbro/serpentinite border zone. Pottery made from the Granitic/Gabbroic fabric did not match any clay from the Lizard, showing that gabbroic clay was sometimes removed and made into pottery elsewhere in Cornwall. The main clay source near Zoar was used for clay extraction throughout the Bronze Age and Iron Age for pottery which was traded all over Cornwall. Other gabbroic clay sources produced pottery only during certain periods and exclusively supplied particular settlements, such as the Loessic/Gabbroic fabric which was found only at Gear and Caer Vallack. The results suggest that pottery was produced by several small-scale cottage industries, which may have operated on a seasonal, part-time basis and probably formed only part of a wide range of activities located around the Lizard area. [source] The Tree Theme Method as an intervention in psychosocial occupational therapy: Client acceptability and outcomesAUSTRALIAN OCCUPATIONAL THERAPY JOURNAL, Issue 3 2009A. Birgitta Gunnarsson Background/aim:,The Tree Theme Method (TTM) is an intervention in which the client paints trees representing certain periods in his/her life. The intervention comprises five sessions, using trees as a starting point to tell one's life story. This study, which is part of an implementation project, aimed to examine the therapeutic alliance and client satisfaction, in relation to perceptions of everyday occupations and health-related factors, with clients going through a TTM intervention. Methods:,Nine occupational therapists recruited 35 clients, at general outpatient mental health care units, for the TTM intervention. Self-rating instruments, targeting therapeutic alliance (HAq-II), different aspects of daily occupations (Canadian Occupational Performance Measure, Satisfaction with Daily Occupations), health-related factors (Sense of Coherence measure, Mastery Scale, Symptom Checklist-90-R) and client satisfaction (Client Satisfaction Questionnaire), were administrated before and after the intervention. Results:,A good initial therapeutic alliance, experienced by both therapists and clients, was correlated to increased changes regarding occupational performance and self-mastery. According to the therapists' ratings, a good initial therapeutic alliance was correlated to increased sense of coherence and a decreased level of psychiatric symptoms. The results showed positive significant changes in occupational performance and health-related factors. High ratings of the therapeutic alliance by the therapists were also related to high client satisfaction. Conclusions:,The TTM seemed to function well in psychosocial occupational therapy, but there is a need for further implementation studies to deepen our understanding of the treatment process, comprising both technique and formation of the therapeutic alliance. [source] | ||||||||||||||||||||||