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Selected AbstractsThe bone histology of osteoderms in temnospondyl amphibians and in the chroniosuchian BystrowiellaACTA ZOOLOGICA, Issue 1 2010Florian Witzmann Abstract Witzmann, F. and Soler-Gijón, R. 2010. The bone histology of osteoderms in temnospondyl amphibians and in the chroniosuchian Bystrowiella. ,Acta Zoologica (Stockholm) 91: 96,114 Bone histology of osteoderms in the armoured temnospondyl Peltobatrachus, plagiosaurids (Gerrothorax, Plagiosuchus) and dissorophids (Aspidosaurus, Cacops, Platyhystrix), as well as in the chroniosuchian Bystrowiella, is studied. The massive osteoderms of Peltobatrachus and Gerrothorax consist of homogeneous parallel-fibred bone, whereas in dissorophids, a lightly built, trabecular middle region is mantled by a thin cortex that is composed of a plywood-type structure. In Bystrowiella and Plagiosuchus, the osteoderms consist to a large degree of interwoven primary fibres and have cell lacunae that bear stumpy canaliculi. The differences in the histological structure of dissorophids and plagiosaurids suggest an iterative evolution of osteoderms. Furthermore, histology in Plagiosuchus indicates a metaplastic development of the osteoderms, whereas the osteoderms of Gerrothorax represent periosteal ossifications as in dissorophids. This suggests a convergent origin of osteoderms also within plagiosaurids. The extensive armour in Gerrothorax probably constituted a calcium reservoir, indicated by cyclical resorption events preserved in the external cortex and interpreted as a physiological response to periodic changes in salinity of the aquatic environment. In contrast, the unique osteoderm structure of dissorophids provides maximum stability and minimum bone mass, and is coherent with the interpretation that the osteoderms served to strengthen the vertebral column during terrestrial locomotion. [source] When documents are destroyed or lost: lay people and archives in the early Middle AgesEARLY MEDIEVAL EUROPE, Issue 4 2002Warren Brown In this paper, I discuss some largely unexplored evidence about lay archives in early medieval Europe. This evidence consists of a set of formulae from late Roman, Merovingian, and Carolingian Gaul, and from Carolingian Bavaria. According to these formulae, lay men and women in these regions from the sixth to the ninth centuries kept documents in private archivesbecause they regarded documents as vital to the security of their property holdings. The manuscripts in which the formulae survive indicate that lay people continued to keep archives throughout the ninth century and into the tenth. They also suggest, however, that by the end of the eighth century traditions about how lay people used and stored documents were being preserved and maintained to a large degree by churches and monasteries. [source] Sediment budget for an eroding peat-moorland catchment in northern EnglandEARTH SURFACE PROCESSES AND LANDFORMS, Issue 5 2005Martin Evans Abstract This paper describes a detailed contemporary sediment budget from a small peat-covered, upland catchment in Upper Teesdale, northern England. The sediment budget was constructed by measuring: (1) sediment transfers on slopes, (2) sediment flux on the floodplain and through the main stream channel and (3) sediment yield at the catchment outlet. Measurements were taken over a four-year monitoring period between July 1997 and October 2001 when interannual variations in runoff were relatively small. Three sites were selected to represent the major erosion subsystems within the catchment: an area of bare peat flats, a pair of peat gullies, and a 300 m channel reach. Collectively the sites allow detailed characterization of the main patterns of sediment flux within the catchment and can be scaled up to provide an estimate of the sediment budget for the catchment as a whole. This constitutes the first attempt to provide a complete description of the functioning of the sediment system in eroding blanket peatlands. Results demonstrate that fluvial suspended sediment flux is controlled to a large degree by channel processes. Gully erosion rates are high but coupling between the slopes and channels is poor and therefore the role of hillslope sediment supply to catchment output is reduced. Consequently contemporary sediment export from the catchment is controlled primarily by in-channel processes. Error analysis of the sediment budgets is used to discuss the limitations of this approach for assessing upland sediment dynamics. A 60 per cent reduction in fluvial suspended sediment yield from Rough Sike over the last 40 years correlates with photographic evidence of significant re-vegetation of gullies over a similar period. This strongly suggests that the reduced sediment yields are a function of increased sediment storage at the slope,channel interface, associated with re-vegetation. Copyright © 2005 John Wiley & Sons, Ltd. [source] Cover Picture: Electrophoresis 9/2008ELECTROPHORESIS, Issue 9 2008Article first published online: 28 APR 200 Regular issues provide a wide range of research and review articles covering all aspects of electrophoresis. Here you will find cutting-edge articles on methods and theory, instrumentation, nucleic acids, CE and CEC, miniaturization and microfluidics, proteomics and two-dimensional electrophoresis. The 20 papers gathered here span areas across miniaturization theory, basic technologies and applications. While not comprehensive, this special issue represents a selection of the state-of-the-art science of miniaturization and its application in various areas of life sciences. We feel to a large degree that this special issue sets a good foundation, and we are looking forward to another thought-provoking update in the near future. Issue 9 also offers one Fast Track article describing particularly important investigations in electrophoresis: "AC Electrokinetic separation and detection of DNA nanoparticles in high conductance solutions." [source] Community heterogeneity and single-cell digestive activity of estuarine heterotrophic nanoflagellates assessed using lysotracker and flow cytometryENVIRONMENTAL MICROBIOLOGY, Issue 7 2010Eva Sintes Summary Heterotrophic nanoflagellates (HNFs) are an essential component of all aquatic microbial food webs, and yet the exploration of the numerical and single-cell responses of these organisms in mixed assemblages still represents a major technical challenge. LysoTracker Green staining combined with flow cytometry was recently proposed for the enumeration of aquatic HNFs. Here we show that LysoTracker Green not only allows the enumeration of HNFs in estuarine samples with a wide range of HNF abundances, but also allows the discrimination of distinct HNF populations in mixed assemblages. In addition, the resulting cytometric parameters can be used to characterize cell size and the level of activity of the cells in the different populations that are detected. LysoTracker Green accumulates preferentially in lysosomes, and we demonstrate that the green fluorescence emission from HNF cells stained with LysoTracker strongly correlates with cell-specific ,-glucosaminidase (,-Gam) activity, a key digestive enzyme of lysosomal origin in eukaryotic cells. Our results further show that different populations that develop in estuarine regrowth cultures are characterized by different intrinsic ranges of size and of feeding activity, and that there is a wide range of single-cell responses within these HNF populations. We found a large degree of uncoupling between cell size and feeding activity, both between and within HNF populations, and there appears to be no clear allometric scaling of feeding activity. We were able to reconstruct the succession of distinct HNF populations that developed during the regrowth experiments, and explore the complex interactions that occurred between numerical (change in abundance of the cytometric populations) and single-cell HNF responses. [source] Synthesis and Characterization of Radical Cations Derived from Mono- and Biferrocenyl-Substituted 2-Aza-1,3-butadienes: A Study of the Influence of an Asymmetric and Oxidizable Bridge on Intramolecular Electron TransferEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 12 2005Vega Lloveras Abstract The synthesis and study of structural and electronic properties of mono-ferrocenyl ,-conjugated complexes 5a,d, whose electronic characteristics have been systematically varied by introducing an electron-donating or electron-withdrawing substituent either at the 1-position or at the 4-position of the 2-aza-1,3-butadiene moiety linked to the ferrocenyl unit, are presented. The structural and electronic properties of the homobimetallic complex 5f, with two ferrocene units linked through the asymmetric and oxidizable 2-aza-1,3-butadiene bridge, is also reported. The crystal structures of complexes 5b, 5d, and 5f show a large degree of conjugation in this family of compounds. Complexes 5 show a rich electrochemical behavior due both to the oxidation of ferrocenyl units and the 2-aza-1,3-butadiene bridge, as revealed by cyclic voltammetry. Radical cations 5+· were prepared from 5 by coulometric oxidations following their generation by absorption spectroscopy. The electronic properties of all reported neutral and oxidized ,-conjugated complexes have been investigated by means of UV/Vis,near-IR, EPR and 57Fe Mössbauer spectroscopy. The detailed study of mono-oxidized species 5a+·,5f+· has permitted the determination of the influence of an asymmetric bridge with an electroactive character on the intramolecular electron transfer (IET) phenomenon, thus demonstrating that the 2-aza-1,3-butadiene bridge promotes the IET between the two metallic units of 5f+· through two different pathways. The experimental data and conclusions are supported by DFT computations (B3LYP/3-21G*) and time-dependent DFT methods. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Prepare for conflict: EEG correlates of the anticipation of target competition during overt and covert shifts of visual attentionEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 9 2010Simon P. Kelly Abstract When preparing to make a saccadic eye movement in a cued direction, perception of stimuli at the target location is enhanced, just as it is when attention is covertly deployed there. Accordingly, the timing and anatomical sources of preparatory brain activity accompanying shifts of covert attention and saccade preparation tend to exhibit a large degree of overlap. However, there is evidence that preparatory processes are modulated by the foreknowledge of visual distractor competition during covert attention, and it is unknown whether eye movement preparation undergoes equivalent modulation. Here we examine preparatory processes in the electroencephalogram of human participants during four blocked versions of a spatial cueing task, requiring either covert detection or saccade execution, and either containing a distractor or not. As in previous work, a typical pattern of spatially selective occipital, parietal and frontal activity was seen in all task versions. However, whereas distractor presence called on an enhancement of spatially selective visual cortical modulation during covert attention, it instead called on increased activity over frontomedial oculomotor areas in the case of overt saccade preparation. We conclude that, although advance orienting signals may be similar in character during overt and covert conditions, the pattern by which these signals are modulated to ameliorate the behavioral costs of distractor competition is highly distinct, pointing to a degree of separability between the overt and covert systems. [source] Soil solution concentration of Cd and Zn canbe predicted with a CaCl2 soil extractEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 1 2003F. Degryse Summary Risk assessment of heavy metals in soil requires an estimate of the concentrations in the soil solution. In spite of the numerous studies on the distribution of Cd and Zn in soil, few measurements of the distribution coefficient in situ, Kd, have been reported. We determined the Kd of soils contaminated with Cd and Zn by measuring metal concentrations in the soil and in the soil solution and attempted to predict them from other soil variables by regression. Soil pH explained most of the variation in logKd (R2 = 0.55 for Cd and 0.70 for Zn). Introducing organic carbon content or cation exchange capacity (CEC) as second explanatory variable improved the prediction (R2 = 0.67 for Cd and 0.72 for Zn), but these regression models, however, left more than a factor of 10 of uncertainty in the predicted Kd. This large degree of uncertainty may partly be due to the variable degree of metal fixation in contaminated soils. The labile metal content was measured by isotopic dilution (E value). The E value ranged from 18 to 92% of the total metal content for Cd and from 5 to 68% for Zn. The prediction of Kd improved when metals in solution were assumed to be in equilibrium with the labile metal pool instead of the total metal pool. It seems necessary therefore to discriminate between ,labile' and ,fixed' pools to predict Kd for Cd and Zn in field contaminated soils accurately. Dilute salt extracts (e.g. 0.01 m CaCl2) can mimic soil solution and are unlikely to extract metals from the fixed pool. Concentrations of Cd and Zn in the soil solution were predicted from the concentrations of Cd and Zn in a 0.01 m CaCl2 extract. These predictions were better correlated with the observations for field contaminated soils than the predictions based on the regression equations relating logKd to soil properties (pH, CEC and organic C). [source] Morphological variation over ontogeny and environments in resource polymorphic arctic charr (Salvelinus alpinus)EVOLUTION AND DEVELOPMENT, Issue 3 2010Kevin J. Parsons SUMMARY Natural selection requires genetically based phenotypic variation to facilitate its action and cause adaptive evolution. It has become increasingly recognized that morphological development can become canalized likely as a result of selection. However, it is largely unknown how selection may influence canalization over ontogeny and differing environments. Changes in environments or colonization of a novel one is expected to result in adaptive divergence from the ancestral population when selection favors a new phenotypic optimum. In turn, a novel environment may also expose variation previously hidden from natural selection. We tested for changes in phenotypic variation over ontogeny and environments among ecomorphs of Arctic charr (Salvelinus alpinus) from two Icelandic lakes. Populations represented varying degrees of ecological specialization, with one lake population possessing highly specialized ecomorphs exhibiting a large degree of phenotypic divergence, whereas the other displayed more subtle divergence with more ecological overlap. Here we show that ecomorphs hypothesized to be the most specialized in each lake possess significant reductions in shape variation over ontogeny regardless of environmental treatment suggesting canalized development. However, environments did change the amount of shape variation expressed in these ecomorphs, with novel environments slowing the rate at which variation was reduced over ontogeny. Thus, environmental conditions may play an important role in determining the type and amount of genetically based phenotypic variation exposed to natural selection. [source] Comparative gene expression in the heads of Drosophila melanogaster and Tribolium castaneum and the segmental affinity of the Drosophila hypopharyngeal lobesEVOLUTION AND DEVELOPMENT, Issue 1 2009Andrew D. Economou SUMMARY Drosophila melanogaster has long played an important role in debates surrounding insect and arthropod head segmentation. It is surprising, therefore, that one important feature of Drosophila head segmentation has remained controversial: namely the position of the boundary between the intercalary and mandibular segments. The Drosophila embryonic head has a pair of structures lying behind the stomodeum known as the hypopharyngeal lobes. Traditionally they have been seen as part of the intercalary segment. More recent work looking at the position of the lobes relative to various marker genes has been somewhat equivocal: segment polarity gene expression has been used to argue for a mandibular affinity of these lobes, while the expression of the anterior-most hox gene labial (lab) has supported an intercalary affinity. We have addressed the question of the segmental affinity of the hypopharyngeal lobes by conducting a detailed comparison of gene expression patterns between Drosophila and the red flour beetle Tribolium castaneum, in which the intercalary segment is unambiguously marked out by lab. We demonstrate that there is a large degree of conservation in gene expression patterns between Drosophila and Tribolium, and this argues against an intercalary segment affinity for the hypopharyngeal lobes. The lobes appear to be largely mandibular in origin, although some gene expression attributed to them appears to be associated with the stomodeum. We propose that the difficulties in interpreting the Drosophila head result from a topological shift in the Drosophila embryonic head, associated with the derived process of head involution. [source] Categorizing approaches combining rule-based and case-based reasoningEXPERT SYSTEMS, Issue 2 2007Jim Prentzas Abstract: Rule-based and case-based reasoning are two popular approaches used in intelligent systems. Rules usually represent general knowledge, whereas cases encompass knowledge accumulated from specific (specialized) situations. Each approach has advantages and disadvantages, which are proved to be complementary to a large degree. So, it is well justified to combine rules and cases to produce effective hybrid approaches, surpassing the disadvantages of each component method. In this paper, we first present advantages and disadvantages of rule-based and case-based reasoning and show that they are complementary. We then discuss the deficiencies of existing categorization schemes for integrations of rule-based and case-based representations. To deal with these deficiencies, we introduce a new categorization scheme. Finally, we briefly present representative approaches for the final categories of our scheme. [source] Triple-Shape Polymeric Composites (TSPCs)ADVANCED FUNCTIONAL MATERIALS, Issue 16 2010Xiaofan Luo Abstract In this paper, the fabrication and characterization of triple-shape polymeric composites (TSPCs) that, unlike traditional shape memory polymers (SMPs), are capable of fixing two temporary shapes and recovering sequentially from the first temporary shape (shape 1) to the second temporary shape (shape 2), and eventually to the permanent shape (shape 3) upon heating, are reported. This is technically achieved by incorporating non-woven thermoplastic fibers (average diameter ,760 nm) of a low- Tm semicrystalline polymer into a Tg -based SMP matrix. The resulting composites display two well-separated transitions, one from the glass transition of the matrix and the other from the melting of the fibers, which are subsequently used for the fixing/recovery of two temporary shapes. Three thermomechanical programming processes with different shape fixing protocols are proposed and explored. The intrinsic versatility of this composite approach enables an unprecedented large degree of design flexibility for functional triple-shape polymers and systems. [source] Geolocation of Atlantic cod (Gadus morhua) movements in the Gulf of Maine using tidal informationFISHERIES OCEANOGRAPHY, Issue 4 2007J. P. GRÖGER Abstract Information derived from archival tags (digital storage tags, DSTs) were used to backtrack the migration of 11 tagged Atlantic cod (Gadus morhua) during 2001 in Massachusetts Bay, the Gulf of Maine, and Georges Bank. The DST tags continuously recorded time, temperature and depth. To geolocate fish positions during its time at large, we first extracted the tidal signal from the pressure recordings on the DST tags, and then compared the resulting data to data predicted with a Massachusetts Bay tidal model that provided us with geographical coordinates at a given date and time. Using least-squares criteria within an estimated geographical region of confidence that was constrained by biological and statistical information (e.g. swimming speed, known release and recapture location, and bottom depth) we were able to geolocate the fish. The resultant geolocated migration tracks indicate a large degree of movement of Atlantic cod in the region and an elevated importance of the Great South Channel (GSC) migration corridor between Massachusetts Bay and the western Georges Bank and Nantucket Shoals region. This observation contrasts strongly with inferences of limited movements by Atlantic cod based on conventional tag recapture methods (mean of 1200 km traveled versus 44 km traveled as measured by conventional tagging and geolocation, respectively). This study demonstrates that geolocation methodologies applied to archival tag studies hold great promise of becoming an important new tool for fisheries managers to quantify the movements of fishes. It also points out the need for greater collaboration between fisheries scientists and oceanographers, and particularly for the development of improved tidal models to cover stock regions more accurately and with higher precision. [source] Institutional and curricular characteristics of leading graduate HRD programs in the United StatesHUMAN RESOURCE DEVELOPMENT QUARTERLY, Issue 2 2002K. Peter Kuchinke HRD graduate programs form an important component of the system of human resource education in the United States. This study investigated the institutional and curricular characteristics of fifty-five leading programs in this country, focusing on three areas: institutional arrangements, student enrollment, and core curriculum content. Findings include a large degree of heterogeneity among program names, departmental affiliations, and specializations. Compared to data from 1991, student enrollment has declined at the master's level while part-time course taking has increased. Analysis of the core curriculum at these institutions showed a disparity between course offerings and much current writing in the field. [source] Hydrology and nitrogen balance of a seasonally inundated Danish floodplain wetlandHYDROLOGICAL PROCESSES, Issue 3 2004Hans Estrup Andersen Abstract This paper characterizes a seasonally inundated Danish floodplain wetland in a state close to naturalness and includes an analysis of the major controls on the wetland water and nitrogen balances. The main inputs of water are precipitation and percolation during ponding and unsaturated conditions. Lateral saturated subsurface flow is low. The studied floodplain owes its wetland status to the hydraulic properties of its sediments: the low hydraulic conductivity of a silt,clay deposit on top of the floodplain maintains ponded water during winter, and parts of autumn and spring. A capillary fringe extends to the soil surface, and capillary rise from groundwater during summer maintains near-saturated conditions in the root zone, and allows a permanently very high evapotranspiration rate. The average for the growing season of 1999 is 3·6 mm day,1 and peak rate is 5·6 mm day,1. In summer, the evapotranspiration is to a large degree supplied by subsurface storage in a confined peat layer underlying the silt,clay. The floodplain sediments are in a very reduced state as indicated by low sulphate concentrations. All nitrate transported into the wetland is thus denitrified. However, owing to modest water exchange with surrounding groundwater and surface water, denitrification is low; 71 kg NO3,N ha,1 during the study period of 1999. Reduction of nitrate diffusing into the sediments during water ponding accounts for 75% of nitrate removal. Biomass production and nitrogen uptake in above-ground vegetation is high,8·56 t dry matter ha,1 year,1 and 103 kg N ha,1 year,1. Subsurface ammonium concentrations are high, and convective upward transport into the root zone driven by evapotranspiration amounted to 12·8 kg N ha,1year,1. The floodplain wetland sediments have a high nitrogen content, and conditions are very favourable for mineralization. Mineralization thus constitutes 72% of above-ground plant uptake. The study demonstrates the necessity of identifying controlling factors, and to combine surface flow with vadose and groundwater flow processes in order to fully comprehend the flow and nitrogen dynamics of this type of wetland. Copyright © 2004 John Wiley & Sons, Ltd. [source] The ontogeny of diurnal rhythmicity in bed-sharing and solitary-sleeping infants: a preliminary report,INFANT AND CHILD DEVELOPMENT, Issue 4 2007Melissa M. Burnham Abstract The purpose of the current study was to investigate the development of sleep,wake and melatonin diurnal rhythms over the first 3 months of life, and the potential effect of bed-sharing on their development. It was hypothesized that increased maternal contact through bed-sharing would affect the development of rhythms in human infants. Ten solitary-sleeping and 8 bed-sharing infants' sleep,wake patterns and melatonin secretion were examined for 72 h at 1 and 3 months of age in their homes. Infants wore actigraphs on their ankles to study sleep,wake patterns. 6-Sulphatoxymelatonin was obtained through urine extracted from each diaper used over the 72-h study period. No significant differences were apparent in the timing of appearance or magnitude of sleep,wake or melatonin rhythms between bed-sharing and solitary-sleeping infants. Sleep,wake results were in the expected direction, with bed-sharing infants displaying more robust rhythms. A large degree of individual variability was evident in both rhythms, especially at 1 month. Three infants' parents regularly used a bright light source at night for feedings and diaper changes; the rhythms of these infants were less robust than the rest of the sample. Trends were mostly in the hypothesized direction and deserve attempts at replication with a larger sample. Copyright © 2007 John Wiley & Sons, Ltd. [source] Augmented Lagrangian coordination for distributed optimal design in MDOINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 13 2008S. Tosserams Abstract Quite a number of coordination methods have been proposed for the distributed optimal design of large-scale systems consisting of a number of interacting subsystems. Several coordination methods are known to have numerical convergence difficulties that can be explained theoretically. The methods for which convergence proofs are available have mostly been developed for so-called quasi-separable problems (i.e. problems with individual subsystems coupled only through a set of linking variables, not through constraints and/or objectives). In this paper, we present a new coordination approach for multidisciplinary design optimization problems with linking variables as well as coupling objectives and constraints. Two formulation variants are presented, offering a large degree of freedom in tailoring the coordination algorithm to the design problem at hand. The first, centralized variant introduces a master problem to coordinate coupling of the subsystems. The second, distributed variant coordinates coupling directly between subsystems. Our coordination approach employs an augmented Lagrangian penalty relaxation in combination with a block coordinate descent method. The proposed coordination algorithms can be shown to converge to Karush,Kuhn,Tucker points of the original problem by using the existing convergence results. We illustrate the flexibility of the proposed approach by showing that the analytical target cascading method of Kim et al. (J. Mech. Design-ASME 2003; 125(3):475,480) and the augmented Lagrangian method for quasi-separable problems of Tosserams et al. (Struct. Multidisciplinary Opt. 2007, to appear) are subclasses of the proposed formulations. Copyright © 2007 John Wiley & Sons, Ltd. [source] Kinetics and mechanism of the reaction of para -chlorophenyl aryl chlorophosphates with anilines in acetonitrileINTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 11 2002Hai Whang Lee The kinetics and mechanism of the nucleophilic substitution reactions of p -chlorophenyl aryl chlorophosphates (2) with anilines are investigated in acetonitrile at 55°C. Relatively large magnitudes of ,X and ,X values are indicative of a large degree of bond making in the TS. Smaller magnitudes of ,X (0.20 for X = H) and ,XY (,0.30) than those for the corresponding reactions with phenyl aryl chlorophosphates (1) (,X = 0.54 for X = H and ,XY = ,1.31) are interpreted to indicate partial electron loss, or shunt, towards the electron acceptor equatorial ligand (p -ClC6H4O-) in the bipyramidal pentacoordinated transition state. The inverse secondary kinetic isotope effects (kH/kD = 0.64,0.87) involving deuterated aniline (ND2C6H4X) nucleophiles, and small ,H, and large negative ,S, are obtained. These results are consistent with a concerted nucleophilic substitution mechanism. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 34: 632,637, 2002 [source] European Alpine moisture variability for 1800,2003INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 4 2007G. van der Schrier Abstract Moisture availability for the European Greater Alpine region (GAR) (43°N,49°N and 4°E,19°E) for the period 1800,2003 is analyzed on the basis of maps of monthly self-calibrating Palmer Drought Severity Index (scPDSI) with a 10, × 10, spatial resolution. To represent the impact of seasonal snow cover on the water budget, a simple snow-accumulation and snowmelt model is added to the water balance calculations on which the (self-calibrating) Palmer Drought Severity Index is based. Over the region as a whole, the late 1850s into the 1870s and the 1940s to the early 1950s stand out as persistent and exceptionally dry periods, whereas the first two decades of the nineteenth century and the 1910s were exceptionally wet periods. Dividing the Greater Alpine Region into four subregions, with the subregions based on coherence of precipitation variability, we find a large degree of heterogeneity in the behavior of the drought index over the subregions. The driest summers on record, in terms of the amplitude of the index averaged over the Alpine region, are 1865 and 2003. In these years, 75.6% and 85.1% of the region was suffering from a moderate drought (or worse). The areas northwest of the high mountains were affected most severely in the 1865 drought, whereas the 2003 drought impacted all subregions more equally. By substituting climatological monthly mean temperatures, from the period 1961,1990, for the actual monthly means in the parameterization for potential evaporation, an estimate is made of the direct effect of temperature on drought. It is observed that a major cause for the vast areal extent of the area affected by the summer drought in the last decade is the high temperatures. Temperatures in the 12 months preceding and including the summer of 2003 explain an increase in the area percentage with moderate (or worse) drought of 31.2%. Copyright © 2006 Royal Meteorological Society [source] Use of the Zarit scale for assessing caregiver burden and collapse in caregiving at home in dementiasINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 10 2007Ana M. Gort Abstract Objectives The main objective was to analyse the Zarit scale's (ZS) ability to identify signs of caregiver collapse amongst people looking after patients suffering from dementia. We also evaluated the dimensions most affected by the ZS and risk factors associated with caregiver burden and collapse. Methods We administered the ZS and semi-structured interviews to identify signs of caregiver collapse amongst 66 people looking after patients suffering from dementia. We evaluated the risk factors associated with the patient: age, sex, type of dementia, place of residence, length of illness, behavioural disorders, incontinence, the Barthel index (IB), the Global Deterioration Scale (GDS), Folstein's Mini-Mental State Examination (MMSE) and the use of day-care centres and also risk factors associated with the caregiver: age, sex, relationship with the patient, help received with caring, the patient's illness, other family responsibilities and other work outside the home. Results There was a large degree of agreement between the findings from the interview and the ZS (Kappa,=,0.545; p,<,0.001). With regard to the risk factors evaluated in this study, there was a statistically significant relationship between behavioural disorders and both burden (p,<,0.27) and collapse (p,<,0.17) and between caregiver collapse and the caregiver and patient not living at the same home (p,<,0.27). Conclusion The ZS is not only useful for identifying caregiver burden, but also for predicting main caregiver collapse. Behavioural disorders and not living with the patient are the main causes of caregiver burden and collapse. Copyright © 2007 John Wiley & Sons, Ltd. [source] Refugee Women in Europe: Some Aspects of the Legal and Policy DimensionsINTERNATIONAL MIGRATION, Issue 2 2000Alice Bloch This article presents an overview of the legal and policy issues affecting refugee and asylum-seeking women in European host societies. First, it explores the unique types of persecution experienced by women and shows that the asylum determination process, along with the status of women relative to men, mitigates against the effective protection of women. The legal basis for asylum, the evidential requirements and the procedural norms all reduce the protection which is likely to be conferred upon asylum-seeking women. Second, the article provides an overview of responses to female refugees and asylum-seekers in European countries of asylum. Although there are differences between countries, there is also a large degree of uniformity. For example, there is a lack of recognition and understanding of the diversity and the range of experiences which refugees bring with them, including different social and cultural norms. Moreover, European policies do not provide special provisions to facilitate the settlement of refugee women and instead place barriers to their social and economic participation. Third, the article examines policies for family reunion in different countries and shows that such unfavourable and unsympathetic policies mitigate against the settlement of refugee women. Finally, the article argues that if refugee and asylum-seeking women are to have their cases recognized and to be successfully settled, then there needs to be a complete rethink of legislation and policy in Europe. [source] Competitive On-line StatisticsINTERNATIONAL STATISTICAL REVIEW, Issue 2 2001Volodya Vovk Summary A radically new approach to statistical modelling, which combines mathematical techniques of Bayesian statistics with the philosophy of the theory of competitive on-line algorithms, has arisen over the last decade in computer science (to a large degree, under the influence of Dawid's prequential statistics). In this approach, which we call "competitive on-line statistics", it is not assumed that data are generated by some stochastic mechanism; the bounds derived for the performance of competitive on-line statistical procedures are guaranteed to hold (and not just hold with high probability or on the average). This paper reviews some results in this area; the new material in it includes the proofs for the performance of the Aggregating Algorithm in the problem of linear regression with square loss. Résumé Cet article décrit une approch nouvelle à modelage statistique combinant les techniques mathematiques de statistique Bayesienne avec la philosophie de la theorie de algorithmes compétitives en ligne. Dans cette approche, qui émergeait durant le décennie derniére dans I'informatique, on ne suppose pas que les données sont produites par une mécanaisme stochastique; au lieu de cela, il est prouvé que les procédures statistiques compétitives en ligne atteignent toujours (et non, par exemple, avechaute probabilite) quelque but desirable (explicitant la bonne performance sur les données réeles). Cet article pass en revue des plusieurs résultats dans cette domaine; son matériel neuf comprend les preuves pour la performance de le àlgorithme agrégent dans le probléme de la régression linégression linéaire avec la perte carrée. [source] The Venturesome Economy: How Innovation Sustains Prosperity in a More Connected World,JOURNAL OF APPLIED CORPORATE FINANCE, Issue 1 2009Amar Bhidé Many observers have warned that the next stage of globalization,the offshoring of research and development to China and India,threatens the foundations of Western prosperity. But in this article, the author explains why the doomsayers are likely to be wrong. Using extensive field studies on venture capital-backed businesses to examine how technology is really used to create value in modern economies, this article explains how and why scientific advances abroad generally contribute to prosperity at home, and why trying to maintain the U.S. lead by subsidizing more research or training more scientists is likely to do more harm than good. When breakthrough ideas have no borders, a nation's capacity to exploit cutting-edge research regardless of where it originates is the key to its economic competitiveness. "Venturesome consumption",that is, the willingness and ability of businesses and consumers to use products and technologies derived from scientific research in the most effective ways,is far more important than having a share of the research. And for this reason, well-developed and "venturesome" economies like the U.S. benefit disproportionately from scientific innovations abroad. To cite just one example discussed at length in this article, the success of Apple's iPod owes much to technologies that were developed largely in Asia and Europe. The proven ability of the United States to remain at the forefront of the global "innovation game" reflects the contributions of many players,not just a few brilliant scientists and engineers, but literally millions of U.S. entrepreneurs, managers, financiers, salespersons, and, to a very large degree, U.S. consumers. As long as their venturesome spirit remains alive and well, advances abroad should not be feared but welcomed. [source] Patterns and determinants of shorebird species richness in the circumpolar ArcticJOURNAL OF BIOGEOGRAPHY, Issue 3 2005Sara S. Henningsson Abstract Aim, The intention with this study was first to investigate and describe the broad-scale geographical patterns of species richness of breeding shorebirds (Charadriiformes; families: Charadriidae, Scolopacidae and Haematopodidae) throughout the arctic tundra biome. Secondly, after compensating for the positive relationship between net primary productivity (NPP) and species richness, the relative importance of additional ecological and historical variables for species richness was investigated. The main variables considered are NPP, length of snow- and ice-free season, accessibility of regions depending on migratory flyway systems, tundra area at Pleistocene (120 and 20,18 ka bp) and Holocene (8 ka bp) times, and tundra area at present. Methods, Information on shorebird species breeding distributions was compiled from distribution atlases and species accounts. The breeding distributions of shorebirds with ranges partly or completely in the Arctic (a total of 50 species) were mapped in ArcView 3.2 to create a raster grid layer of shorebird species richness at a 1° latitude × longitude resolution. The total and mean species richness value was calculated per each 10° of longitude sector of the Arctic. The relationships between species richness and the different climatic and environmental variables were analysed on the basis of this sector-wise division of the arctic tundra. The influence of each variable on species richness was investigated using univariate and multivariate analyses (multivariate linear regression and general linear model). Results, We found that patterns of breeding shorebird species richness in the Arctic tundra biome are to a large degree determined by the NPP, the length of the snow- or ice-free season, the diversity of migratory flyways, as well as the historical extent of tundra habitat area during the maximum cooling of the last glacial period. Essentially, two main regions are distinguishable in the circumpolar Arctic regarding shorebird community richness. These are a species-rich Beringia-centred region and a species-poor Atlantic-centred region. Main conclusions, The underlying explanations to these major trends may primarily be attributed to factors that operate at present through accessibility of areas from contemporary migration flyways, as well as processes that operated in the past during and after the last glacial cycle. The most prominent influence on the shorebird diversity was found for NPP in combination with the diversity of migratory flyways. These flyways provide the links between breeding and wintering resources, often separated by huge distances, and the geographical and ecological conditions associated with the shorebirds' migration seem to be of particular importance for their breeding diversity in different sectors of circumpolar tundra. [source] SECONDARY TRAUMATIC STRESS, PSYCHOLOGICAL DISTRESS, SHARING OF TRAUMATIC REMINISCES, AND MARITAL QUALITY AMONG SPOUSES OF HOLOCAUST CHILD SURVIVORSJOURNAL OF MARITAL AND FAMILY THERAPY, Issue 4 2001Rachel Lev-Wiesel In this study, we examined the issue of secondary traumatic stress (STS) among spouses of Holocaust survivors who were children during the World War II. STS is defined as comprising the same components as posttraumatic stress disorder (PTSD), except that the person evidencing the symptoms has not actually been exposed to the traumatic event(s), but has developed them as a result of caring for someone with PTSD. Participants were 90 couples who completed self-report questionnaires regarding posttraumatic symptoms, psychological distress, and marital quality. The results showed that about one-third of the spouses suffered from some degree of STS symptoms. Secondary traumatic stress symptoms and psychological distress among spouses were significantly related to hostility, anger, paranoia, and interpersonal sensitivity in the survivor, but unrelated to whether the survivor had shared his/her reminiscences with the spouse. Female spouses were found to suffer more distress than male spouses, especially when their partner suffered high levels of PTSD. The results suggest that STS is, to a large degree, related to the demands of living with a symptomatic survivor, possibly more than to the empathic element thought to be central to this syndrome. [source] Trophic factors attenuate nitric oxide mediated neuronal and axonal injury in vitro: roles and interactions of mitogen-activated protein kinase signalling pathwaysJOURNAL OF NEUROCHEMISTRY, Issue 6 2005Alastair Wilkins Abstract Inflammation in the central nervous system occurs in diseases such as multiple sclerosis and leads to axon dysfunction and destruction. Both in vitro and in vivo observations have suggested an important role for nitric oxide (NO) in mediating inflammatory axonopathy. The purposes of this study were to model inflammatory axonopathy in vitro and identify modulators of the process. Rat cortical neurones were cultured and exposed to an NO-donor plus potential protective factors. Cultures were then assessed for neuronal survival, axon survival and markers of intracellular signalling pathways. The NO-donor produced dose-dependent neuronal loss and a large degree of axon destruction. Oligodendrocyte conditioned medium (OCM) and insulin-like growth factor type-1 (IGF-1), but not glial cell line-derived neurotrophic factor (GDNF), improved survival of neurones exposed to NO donors. In addition p38 MAP kinase was activated by NO exposure and inhibition of p38 signalling led to neuronal and axonal survival effects. OCM and IGF-1 (but not GDNF) reduced p38 activation in NO-exposed cortical neurones. OCM, IGF-1 and GDNF improved axon survival in cultures exposed to NO, a process dependent on mitogen-activated protein kinase/extracellular signal-related kinase signalling. This study emphasizes that different mechanisms may underlie neuronal/axonal destructive processes, and suggests that trophic factors may modulate NO-mediated neurone/axon destruction via specific pathways. [source] Factors Determining Grain Orientation in Bismuth Sodium Potassium Titanate,Lead Zirconate Titanate Solid Solutions Made by the Reactive Templated Grain Growth MethodJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 5 2002Yuichi Abe Grain-oriented Bi0.5(Na0.85K0.15)0.5TiO3 -Pb(Zr1,xTix)O3 (BNKT-PZT) ceramics were prepared via the reactive templated grain growth method, using platelike Bi4Ti3O12 particles. Factors that determine the degree of orientation were examined. Prereacted PZT gave a larger degree of orientation than PZT raw materials (PbO, ZrO2, and TiO2) in the 75BNKT-25PZT (x= 0.5) system. Increases in the titanium concentration in the PZT of the 75BNKT-25PZT system and in the BNKT concentration in the yBNKT-(100 ,y)PZT (x= 0.5) system increased the degree of orientation. The direction of material transport between BNKT and PZT was important to obtain ceramics with a large degree of orientation. [source] CLIMATE CHHANGE SENSITIVITY ASSESSMENT ON UPPER MISSISSIPPI RIVER BASIN STREAMFLOWS USING SWAT,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 4 2006Manoj Jha ABSTRACT: The Soil and Water Assessment Tool (SWAT) model was used to assess the effects of potential future climate change on the hydrology of the Upper Mississippi River Basin (UMRB). Calibration and validation of SWAT were performed using monthly stream flows for 1968,1987 and 1988,1997, respectively. The R2 and Nash-Sutcliffe simulation efficiency values computed for the monthly comparisons were 0.74 and 0.69 for the calibration period and 0.82 and 0.81 for the validation period. The effects of nine 30-year (1968 to 1997) sensitivity runs and six climate change scenarios were then analyzed, relative to a scenario baseline. A doubling of atmospheric CO2 to 660 ppmv (while holding other climate variables constant) resulted in a 36 percent increase in average annual streamflow while average annual flow changes of ,49, ,26, 28, and 58 percent were predicted for precipitation change scenarios of ,20, ,10, 10, and 20 percent, respectively. Mean annual streamflow changes of 51,10, 2, ,6, 38, and 27 percent were predicted by SWAT in response to climate change projections generated from the CISRO-RegCM2, CCC, CCSR, CISRO-Mk2, GFDL, and HadCMS general circulation model scenarios. High seasonal variability was also predicted within individual climate change scenarios and large variability was indicated between scenarios within specific months. Overall, the climate change scenarios reveal a large degree of uncertainty in current climate change forecasts for the region. The results also indicate that the simulated UMRB hydrology is very sensitive to current forecasted future climate changes. [source] Bayesian inference in hidden Markov models through the reversible jump Markov chain Monte Carlo methodJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES B (STATISTICAL METHODOLOGY), Issue 1 2000C. P. Robert Hidden Markov models form an extension of mixture models which provides a flexible class of models exhibiting dependence and a possibly large degree of variability. We show how reversible jump Markov chain Monte Carlo techniques can be used to estimate the parameters as well as the number of components of a hidden Markov model in a Bayesian framework. We employ a mixture of zero-mean normal distributions as our main example and apply this model to three sets of data from finance, meteorology and geomagnetism. [source] Controlled free-radical polymerization of vinyl chlorideJOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 3 2005Dietrich Braun Owing to the importance of poly(vinyl chloride) (PVC) as the second-largest plastic in volume after the polyolefins and above styrene polymers, the control of the free-radical polymerization of vinyl chloride (VC) is of high industrial and academic interest. But still the term "controlled" polymerization is not yet clearly defined. Often it is used for quasi-living polymerizations with equilibrium reactions in the initiation and/or termination step or for the control of the molecular weight distribution (MWD), but it can also be applied to several structural aspects such as stereochemistry, branching, or special technical properties. In the present article, the control of chain growth and chain transfer is discussed. It has been well known for many years that the propagation step in the VC polymerization is terminated to a large degree by the rather frequent and temperature-dependent chain transfer of the growing macromolecules to the monomer. Therefore, the degree of polymerization is strongly governed by the polymerization temperature. However, this transfer step does not result in a controlled or a narrow MWD. By means of free-radical nitroxide-mediated polymerization of VC in suspension, PVC with a narrower MWD can be obtained also at higher polymerization temperatures. The resulting PVC with nitroxide end groups can act as a macro-initiator for various monomers, resulting in two-block copolymers, which are, e.g., interesting compatibilizers in blends with PVC. J. VINYL ADDIT. TECHNOL., 11:86,90, 2005. © 2005 Society of Plastics Engineers [source] | |||||||||||||||||||||||||||||||||||||