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Upper‐flow‐regime bedforms, including upper‐stage‐plane beds, antidunes, chutes‐and‐pools and cyclic steps, are ubiquitous in glacigenic depositional environments characterized by abundant meltwater discharge and sediment supply. In this study, the depositional record of Froude near‐critical and supercritical flows in glacigenic settings is reviewed, and similarities and differences between different depositional environments are discussed. Upper‐flow‐regime bedforms may occur in subglacial, subaerial and subaqueous environments, recording deposition by free‐surface flows and submerged density flows. Although individual bedform types are generally not indicative of any specific depositional environment, some observed trends are similar to those documented in non‐glacigenic settings. Important parameters for bedform evolution that differ between depositional environments include flow confinement, bed slope, aggradation rate and grain size. Cyclic‐step deposits are more common in confined settings, like channels or incised valleys, or steep slopes of coarse‐grained deltas. Antidune deposits prevail in unconfined settings and on more gentle slopes, like glacifluvial fans, sand‐rich delta slopes or subaqueous (ice‐contact) fans. At low aggradation rates, only the basal portions of bedforms are preserved, such as scour fills related to the hydraulic‐jump zone of cyclic steps or antidune‐wave breaking, which are common in glacifluvial systems and during glacial lake‐outburst floods and (related) lake‐level falls. Higher aggradation rates result in increased preservation potential, possibly leading to the preservation of complete bedforms. Such conditions are met in sediment‐laden jökulhlaups and subaqueous proglacial environments characterized by expanding density flows. Coarser‐grained sediment leads to steeper bedform profiles and highly scoured facies architectures, while finer‐grained deposits display less steep bedform architectures. Such differences are in part related to stronger flows, faster settling of coarse clasts, and more rapid breaking of antidune waves or hydraulic‐jump formation over hydraulically rough beds. [ABSTRACT FROM AUTHOR]

Objective We examined the costs and benefits of introducing migraine nurses into primary care. Background Migraine is one of the most costly neurological diseases. Methods We analyzed data from our earlier nonrandomized cohort study comparing an intervention group of 141 patients, whose care was supported by nurses trained in migraine management, and a control group of 94 patients receiving usual care. Estimates of per-person direct costs were based on nurses' salaries and referrals to neurologists. Indirect costs were estimated as lost productivity, including numbers of days of absenteeism or with <50% productivity at work due to migraine, and notional costs related to lost days of household activities or days of <50% household productivity. Analysis was conducted from the payer's perspective. Results After 9 months the direct costs were €281.11 in the control group against €332.23 in the intervention group (mean difference −51.12; 95% CI: −113.20-15.56; P = .134); the indirect costs were €1985.51 in the control group against €1631.75 in the intervention group (mean difference 353.75; 95% CI: −355.53-1029.82; P = .334); and total costs were €2266.62 in the control group, against €1963.99 in the intervention group (mean difference 302.64; 95% CI: −433.46-1001.27; P = .438). When costs attributable to lost household productivity were included, total costs increased to €6076.62 in the control group and €5048.15 in the intervention group (mean difference 1028.47; 95% CI: −590.26-2603.67; P = .219). Conclusion Migraine nurses in primary care seemed in this study to increase practice costs but decrease total societal costs. However, it was a nonrandomized study, and the differences did not reach significance. For policy-makers concerned with headache-service organization and delivery, the important messages are that we found no evidence that nurses increased overall costs, and investment in a definitive study would therefore be worthwhile. [ABSTRACT FROM AUTHOR]

Our objective is to understand general causes of different river channel patterns. In this paper we compare an empirical stream power-based classification and a physics-based bar pattern predictor. We present a careful selection of data from the literature that contains rivers with discharge and median bed particle size ranging over several orders of magnitude with various channel patterns and bar types, but no obvious eroding or aggrading tendency. Empirically a continuum is found for increasing specific stream power, here calculated with pattern-independent variables: mean annual flood, valley gradient and channel width predicted with a hydraulic geometry relation. 'Thresholds', above which certain patterns emerge, were identified as a function of bed sediment size. Bar theory predicts nature and presence of bars and bar mode, here converted to active braiding index ( B). The most important variables are actual width-depth ratio and nonlinearity of bed sediment transport. Results agree reasonably well with data. Empirical predictions are somewhat better than bar theory predictions, because the bank strength is indirectly included in the empirical prediction. In combination, empirical and theoretical prediction provide partial explanations for bar and channel patterns. Increasing potential-specific stream power implies more energy to erode banks and indeed correlates to channels with high width-depth ratio. Bar theory predicts that such rivers develop more bars across the width (higher B). At the transition from meandering to braiding, weakly braided rivers and meandering rivers with chutes are found. Rivers with extremely low stream power and width-depth ratios hardly develop bars or dynamic meandering and may be straight or sinuous or, in case of disequilibrium sediment feed, anastomosing. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

VOS is a new mapping technique that can serve as an alternative to the well-known technique of multidimensional scaling (MDS). We present an extensive comparison between the use of MDS and the use of VOS for constructing bibliometric maps. In our theoretical analysis, we show the mathematical relation between the two techniques. In our empirical analysis, we use the techniques for constructing maps of authors, journals, and keywords. Two commonly used approaches to bibliometric mapping, both based on MDS, turn out to produce maps that suffer from artifacts. Maps constructed using VOS turn out not to have this problem. We conclude that in general maps constructed using VOS provide a more satisfactory representation of a dataset than maps constructed using well-known MDS approaches. [ABSTRACT FROM AUTHOR]

van den Berg JWK, Slebos D-J, Postma DS, Dijkhuizen B, Koëter GH, Timens W, van der Bij W, Kauffman HF. Feasibility of sputum induction in lung transplant recipients. Clin Transplant 2004 DOI: 10.1111/j.1399-0012.2004.00237.x © Blackwell Munksgaard, 2004 Sputum induction (SI) is nowadays being applied as a non-invasive and safe method to investigate airway inflammation in pulmonary diseases. We investigated the feasibility of SI after lung transplantation (LTX), and compared sputum and bronchoalveolar lavage (BAL) cellular characteristics and interleukin-8 (IL-8) levels. Results were also compared with 11 healthy subjects. SI as performed between 26 and 1947 d after LTX in 19 recipients, was successful in 16 of 22 attempts (73%). Six patients failed to produce sputum after induction, mostly just post-LTX and with having a lower forced expiratory volume in 1 s (FEV1). The success rate in clinically stable patients after the first month post-LTX was 93%. Side-effects were absent. Sputum recovery, viability and squamous cell contamination were comparable between LTX patients and healthy subjects. In the LTX group, total cell counts, neutrophil percentages and IL-8 levels were much higher in SI than BAL (1.6 × 106/mL, 65.5% and 54.2 ng/mL vs. 0.1 × 106/mL, 3.0% and 0.01 ng/mL; p < 0.001). Although LTX-neutrophil percentages in SI and BAL correlated properly ( ρ = 0.72, p = 0.04), both techniques are not interchangeable. We conclude that sputum induction is feasible, well tolerated, and without major side-effects in stable patients after the first month post-LTX. Induced sputum may be a useful tool to study inflammatory changes of the airways after LTX, and because of the large quantity of neutrophils sampled, especially for further studies on the pathogenesis of bronchiolitis obliterans. [ABSTRACT FROM AUTHOR]

Scientific literature is often fragmented, which implies that certain scientific questions can only be answered by combining information from various articles. In this pa- per, a new algorithm is proposed for finding associations between related concepts present In literature. To this end, concepts are mapped to a multidimensional space by a Hebbian type of learning algorithm using co-occurrence data as input. The resulting concept space allows exploration of the neighborhood of a concept and finding potentially novel relationships between concepts. The obtained information retrieval system is useful for finding literature supporting hypotheses and for discovering previously unknown relationships between concepts. Tests on artificial data show the potential of the proposed methodology. In addition, preliminary tests on a set of Medline abstracts yield promising results. [ABSTRACT FROM AUTHOR]

Abstract Natural, moderately loosely packed sands can only erode from the surface of the bed after an increase in pore volume. Because of this shear dilatancy, negative pore pressures are generated in the bed. In cases of low permeability, these negative pressures are released relatively slowly, which retards the maximum rate of erosion. This effect is incorporated in a new, analytically derived, pick-up function that can explain the observation of gradual retrogressive failure of very steep subaqueous slopes, sometimes more than 5 m high, in fine non-cohesive sands. This process, termed ‘breaching’ in the field of sediment dredging, may produce large failures in sand bars or river banks. The analytical function that describes the breaching process in fine sand is incorporated in a one-dimensional, steady-state numerical model of turbidity currents describing the spatial development of flow. This model is applied to simulate a large ‘flushing’ event in Scripps Submarine Canyon, Pacific coast of California. Breach retrogradation and the successive evolution in time of the resulting turbidity current in the canyon are predicted in a sequence of discrete steps. Predicted velocities are compared with values measured during a flushing event. Implications for the interpretation of deep-water massive sands are discussed. [ABSTRACT FROM AUTHOR]

Large bank failures, comprising up to 106 m3 of sediment, are common features along steep channel banks in estuaries and large rivers that consist of clean, fine sands, and are mostly assumed to be generated by sudden liquefaction of large masses of very loosely packed sand. Another less commonly recognized type of failure is manifested by the gradual retrogression of a very steep wall, steeper than the angle-of-repose. Instead of the voluminous surging plastic sediment-water flow, or hyperconcentrated density flow (sensu Mulder & Alexander, 2001) generated by liquefaction, this type of failure, known as breaching by dredging companies and hydraulic engineers, produces a sustained quasi-steady, turbidity current. To date, sedimentologists have not recognized the process of breaching as such. In this paper, it is suggested that breaching may be the origin of many thick, massive sand layers known from ancient deposits from various environments, notably in some turbidite successions. Possible differences in the sedimentary structure of the deposits produced by breach failures vs. liquefaction slope failures (=liquefaction flow slides) can be deduced from a knowledge of the sediment transport processes initiated by the failure. A field study is presented on some poorly structured beds in the Eocene Vlierzele Sands in Belgium, which are supposed to have originated from liquefaction failures, but are reinterpreted to be the products of breaching. It is postulated that the local steep slope disturbance required to initiate an active breach can be produced by a small liquefaction slope failure (=liquefaction flow slide failure) or local erosion by river or tidal channel flow at the initial stage of the failure event. [ABSTRACT FROM AUTHOR]

This study focuses on four raspberry (Rubus idaeus) genotypes from two different genetic backgrounds: cvs Glen Prosen and Glen Clova, bred at the Scottish Crop Research Institute (SCRI) and genotypes bred at Horticulture Research International (HRI), East Malling (EM), EM 4997 and EM 5007. The ripe fruit of each genotype pair were characterised subjectively by raspberry breeders as relatively firm or soft, respectively. Different stages of fruit development from each genotype were used to quantify fruit firmness, rates of ethylene evolution and ripening rate. Penetrometry data confirmed suspected firmness differences. Firmness correlated with rates of ethylene evolution. Rates of ethylene production also correlated with receptacle size. Storage of green fruits in 20 μl l-1 ethylene reduced fruit firmness, enhanced respiration rate and colour (anthocyanin) development and stimulated the development of cell wall hydrolase activities. However, during natural ripening in the field, fruit respiration rate declined, which indicates a non-climacteric ripening pattern. In drupelets, the activities of polygalacturonase (PG), pectin methylesterase (PME), Cx-cellulase (Cx) and β-galactosidase (β-gal.) increased substantially as ripening progressed. More detailed studies with ripe fruit of cv. Glen Clova indicated major isoforms of PG at pIs 3.3, 8.6 and 10.1; of PME at pIs 7.2, 8.5, 8.7, 8.8; of Cx at pI 2.4; and of β-gal. at pIs 6.3 and 6.7. [ABSTRACT FROM AUTHOR]

Reliable field data obtained by directly measuring bed-load transport of fine- to coarse-grained bed material ate extremely scarce, mainly because of the difficulty of sampling accurately. Therefore, the verification of bed-load transport formulae is largely based on flume experiments, which refer to unrealistic shallow-water conditions. In this study, some bed-load transport formulae were tested against data from natural environments. As an alternative to ascertaining the bed-load transport rate by sampling the bed-load, the transport rate was deduced from data on bedform height and bedform celerity. For this purpose, 43 sets of data from rivers, representing a wide range of bed material, bedform dimensions and hydraulic conditions were collected as were some sets of dam from tidal settings. Two formulae were used for the prediction of the bed-load transport: the formula of Van Rijn (1981) and the Kalinske (1947) formula as approximated by Elzerman & Frijlink (1951) (and, in the present study, slightly modified for application to tidal waters). Both the bed-load function of Van Rijn and the modified formula of Kalinske-Frijlink require data which are easily obtained and that can be measured accurately. At those stages of the flow when bed-load transport was high the Van Rijn function tended to overestimate that transport. For flow stages when bed-load transport was low the opposite was true. The modified Kalinske Frijlink function gave consistently good results: 86% of the transport rates predicted using the river data were within 0·5–2·0 times the values actually measured. [ABSTRACT FROM AUTHOR]