bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modelling human movement in cholera spreading along fluvial systems
Authors: Righetto L. , Bertuzzo E. , Casagrandi R. , Gatto M. , Rodriguez‐Iturbe I. , Rinaldo A. 
Published: June 2010

AbstractWe propose an important extension of a previously studied, spatially explicit and hydrology‐driven, model of cholera spreading. Our reformulation concerns the role of different modelizations of human movement on the overall dynamics of the epidemics, which were previously expressed synthetically by bacterial diffusion. The system is composed of three compartments: susceptible and infected components, Vibrio cholerae dispersion and reaction dynamics. The underlying spatial framework is based on a reaction‐diffusion scheme, which is applied, for simplicity, to ecological corridors modelled as one‐dimensional lattices mimicking river reaches. In this geometry, we are able to predict important features of disease propagation, like the analytical evaluation of the spreading celerity of travelling fronts of epidemics. The explicit mechanism of human movement presented here leads to a comparison with previous approaches, revealing notable differences in how cholera spreads in space and time along the system. Studying human movement allows the analysis of specific quantities useful to policy makers and epidemiologists, such as the value of human diffusion which can generate upstream propagation of the disease. A robust relationship among key parameters, which links together diffusion mechanism, drift speed and resulting epidemic intensity, is also shown. Copyright © 2010 John Wiley & Sons, Ltd.
TGF‐β interactions with IL‐1 family members trigger IL‐4‐independent IL‐9 production by mouse CD4+ T cells
Authors: Uyttenhove Catherine , Brombacher Frank , Van Snick Jacques 
Published: June 2010

AbstractTGF‐β and IL‐4 were recently shown to selectively upregulate IL‐9 production by naïve CD4+ T cells. We report here that TGF‐β interactions with IL‐1α, IL‐1β, IL‐18, and IL‐33 have equivalent IL‐9‐stimulating activities that function even in IL‐4‐deficient animals. This was observed after in vitro antigenic stimulation of immunized or unprimed mice and after polyclonal T‐cell activation. Based on intracellular IL‐9 staining, all IL‐9‐producing cells were CD4+ and 80–90% had proliferated, as indicated by reduced CFSE staining. In contrast to IL‐9, IL‐13 and IL‐17 were strongly stimulated by IL‐1 and either inhibited (IL‐13) or were unaffected (IL‐17) by addition of TGF‐β. IL‐9 and IL‐17 production also differed in their dependence on IL‐2 and regulation by IL‐1/IL‐23. As IL‐9 levels were much lower in Th2 and Th17 cultures, our results identify TGF‐β/IL‐1 and TGF‐β/IL‐4 as the main control points of IL‐9 synthesis.
Transition‐Metal‐Rich Borides – Fascinating Crystal Structures and Magnetic Properties
Authors: Fokwa Boniface P. T. 
Published: June 2010

AbstractThe ability to design and predict new phases in solid‐state chemistry remains a challenge. However, experiment and theory have been working together in the last decade to find new phases with targeted magnetic properties in the family of transition‐metal‐rich borides. These studies were very successful for boride phases crystallizing with the Ti3Co5B2structure type. Furthermore, strong variations of the magnetic properties in some series of compounds as a function of the number of valence electrons were observed experimentally and explained by using density functional theory calculations. The Zn11Rh18B8and Th7Fe3structure types have also produced many magnetically ordered phases, whereas the new Ti1.6Os1.4RuB2and Ti1+xRh2–x+yIr3–yB2structure types have the potential to produce new materials with interesting magnetic properties. The large family of perovskite boride phases has welcomed new members whose structures enable the ordering of boron atoms and vacancies. Renewed interest has been observed for boride phases crystallizing with the Cr23C6‐type structure, whose magnetic properties were mainly studied before the nineties.
1,2‐Oxazines as Building Blocks for Stereoselective Synthesis: Preparation of Oxygen‐Substituted 1,2‐Oxazines, either by Alcohol Addition or by Epoxidation, and Subsequent Hydrogenation Leading to 1,2‐Amino Alcohols and Pyrrolidines
Authors: Zimmer Reinhold , Buchholz Monika , Collas Markus , Angermann Jörg , Homann Kai , Reissig Hans‐Ulrich 
Published: June 2010

AbstractStereodefined oxygen‐substituted 1,2‐oxazines were prepared by three different routes. The cycloaddition of enol ethers such as 1 with α‐nitrosoalkenes generated in situ gave the heterocycles 3 and 4. Acid‐catalysed additions of alcohols to the 6H‐1,2‐oxazines 5 led to mixtures of the adducts 6 and the substitution products 7 with moderate chemoselectivity. Epoxidation of the 6H‐1,2‐oxazines 5 proceeded more efficiently and furnished the corresponding epoxides 25 and 32 in reasonable to excellent yields. It was demonstrated that the resulting oxygen‐substituted 1,2‐oxazines were suitable precursors for the preparation of cyclic or acyclic primary and secondary amines in racemic or enantiopure form. Hydrogenation of the 3‐phenyl‐substituted 1,2‐oxazines 3 and 25a and of (6S)‐ and (6R)‐32 preferentially furnished the 1,2‐amino alcohols 15, rac‐29 and (2S)‐ and (2R)‐29. On the other hand, reduction of the 3‐ethoxycarbonyl‐substituted 1,2‐oxazines 4, 6d and 20 led to the formation of the N‐protected proline esters 21–24 in moderate yields. It was also found that the 5‐methyl‐6H‐1,2‐oxazine 10 was a good precursor for the propargylic ether 11, which allowed a Pauson–Khand reaction leading to the tricyclic compounds 13 and 14. Hydrogen peroxide converted 10 into a hydroperoxide intermediate, which was further transformed into the 1,2‐oxazin‐6‐one 28b. Overall, the results demonstrate the remarkable potential of suitably substituted 1,2‐oxazine derivatives for the stereoselective synthesis of amines.
A simple model of bedform migration
Authors: Bartholdy J. , Ernstsen V.B. , Flemming B.W. , Winter C. , Bartholomä A. 
Published: June 2010

AbstractA model linking subaqueous dune migration to the effective (grain related) shear stress is calibrated by means of flume data for bedform dimensions and migration rates. The effective shear stress is calculated on the basis of a new method assuming a near‐bed layer above the mean bed level in which the current velocity accelerates towards the bedform crest. As a consequence, the effective bed shear stress corresponds to the shear stress acting directly on top of the bedform. The model operates with the critical Shields stress as a function of grain size, and predicts the deposition (volume per unit time and width) of naturally‐packed bed material on the bedform lee side, qbcrest. The model is simple, built on a rational description of simplified sediment mechanics, and its calibration constant can be explained in accordance with estimated values of the physical constants on which it is based. Predicted values of qbcrest correlate with measured values of bedform height multiplied by bedform migration rate with R2 = 0·83. Copyright © 2010 John Wiley & Sons, Ltd.
Effects of turbulence on the transport of individual particles as bedload in a gravel‐bed river
Authors: Paiement‐Paradis Geneviève , Marquis Geneviève , Roy André 
Published: June 2010

AbstractThis study investigates the association between mean and turbulent flow variables and the movement of individual particles in a gravel‐bed river. The experimental design implemented in the Eaton‐North River (Québec, Canada) is based on the simultaneous observations at a high temporal resolution of both particle movements as bedload using an underwater video camera and of the streamwise and vertical flow velocity components using a vertical array of three electromagnetic current meters (ECMs). The frequency and distance of displacement of particles larger than 20 mm that were sliding or rolling on the bed were measured from a 10 minutes long film. Mean and turbulent flow properties obtained for periods without sediment transport are compared to those when particles were sliding and rolling. When particles are sliding, weak differences are present for the mean streamwise velocity and normal vertical stresses. Instantaneous Reynolds shear stresses are significantly lower for sliding events which was not expected but could be explained by the important dominance of Quadrant 3 events (inward interactions). When particles are rolling, only the vertical normal stresses show a weak difference from those observed in the absence of transport but they tend to occur when Quadrant 2 (ejections) dominate the flow field. For both sliding and rolling particles, vertical and/or streamwise fluid accelerations show high magnitude values when compared to periods without transport. For sliding particles, streamwise acceleration is mostly negative and combines most of the time with a positive vertical acceleration. For rolling particles, streamwise and vertical acceleration are predominantly of opposite sign. These results suggest that fluid acceleration or deceleration in the streamwise and vertical directions is affecting the pressure field around particles. In this study, fluid acceleration seems to play a more important role than Reynolds shear stress or normal stresses for bedload movements. Copyright © 2010 John Wiley & Sons, Ltd.
The history of water salinity in the Pearl River estuary, China, during the Late Quaternary
Authors: Zong Yongqiang , Yu Fengling , Huang Guangqing , Lloyd Jeremy M. , Yim Wyss W.‐S. 
Published: June 2010

AbstractThis research reconstructed the Late Quaternary salinity history of the Pearl River estuary, China, from diatom records of four sedimentary cores. The reconstruction was produced through the application of a diatom–salinity transfer function developed based on 77 modern surface sediment samples collected across the estuary from shallow marine environment to deltaic distributaries. The statistical analysis indicates that the majority of sediment samples from the cores has good modern analogues, thus the reconstructions are reliable. The reconstructed salinity history shows the older estuarine sequence formed during the last interglacial was deposited under similar salinity conditions to the younger estuarine sequence, which was formed during the present interglacial. Further analysis into the younger estuarine sequence reveals the interplays between sea level, monsoon‐driven freshwater discharge, and deltaic shoreline movement, key factors that have influenced water salinity in the estuary. In particular, a core from the delta plain shows the effects of sea‐level change and deltaic progradation, while cores from the mouth region of the estuary reveal changes of monsoon‐driven freshwater discharge. This study demonstrates the advantages of quantitative salinity reconstructions to improve the quality of reconstruction and allow direct comparison with other quantitative records and the instrumentally observed values of salinity. Copyright © 2010 John Wiley & Sons, Ltd.
Transgressive dunefield landforms and vegetation associations, Doña Juana, Veracruz, Mexico
Authors: Hesp Patrick , Martinez Marisa , da Silva Graziela Miot , Rodríguez‐Revelo Natalia , Gutierrez Erika , Humanes Adriana , Laínez Daniela , Montaño Irene , Palacios Verónica , Quesada Agustín , Storero Lorena , Trilla Gabriela González , Trochine Carolina 
Published: June 2010

AbstractTransgressive dune fields often comprise a multiplicity of landforms where vegetation processes largely affect landform dynamics, which in turn, also affect vegetation processes. These associations have seldom been studied in detail. This paper examines four separate landform types in a complex coastal transgressive dunefield located in the central Gulf of Mexico, in order to assess the relationships between dunefield habitat, local environmental factors, vegetation associations and landform evolution. Topographic surveys using tape and clinometer were conducted in conjunction with vegetation survey transects at four locations across the Doña Juana dunefield. Vegetation surveys allowed the estimation of relative plant cover of each plant species found along the transects. A large variety of landforms were found at the Doña Juana Dunefield: deflation plains, gegenwalle (counter) ridges, transverse dune trailing ridges, blowouts and parabolic dunes, aklé (fish‐scale shaped) dunefields and precipitation ridges, with plant species associations developing on these different landforms equally variable. Flood tolerant species were located in the lower parts (deflation plain and gegenwalle ridges) whereas the older and dryer parts were covered by coastal matorral shrubs. Burial‐tolerant species were dominant in the most mobile areas (blowouts and aklé dunefield and margin). The dune trailing ridge, with relatively milder conditions, showed the highest richness, with no dominant species. A dual interaction was found such that colonizing species both create and affect topography, and in turn, topography determines vegetation association and succession patterns. In coastal dunes, the vegetation and abiotic environment (namely the different landforms and the inherent micronevironmental variability) interact tightly and generate a complex and highly dynamic biogeomorphic system where substrate mobility and colonization processes reinforce one another in positive feedback. Copyright © 2010 John Wiley & Sons, Ltd.
Long‐runout rockslide on glacier at Tsar Mountain, Canadian Rocky Mountains: potential triggers, seismic and glaciological implications
Authors: Jiskoot Hester 
Published: June 2010

AbstractA rhomboidal shaped rockslide with a length of 2·2 km and an area of 1·35 km2 covers 30% of a small Clemenceau Icefield Group cirque glacier. By means of remote sensing, airborne photography, climate and seismic data analysis, the extent, timing, possible trigger mechanisms, and rockslide effects on the glacier are discussed. An ML 2·0 seismic event on 14 September 2000 represents the rockslide and has a spindle‐shaped waveform and high energy in the low frequencies. Based on a strong signal duration of 56–108 seconds the rockslide had an average runout velocity of 22–45 m s−1. Stress fatigue and a combination of rain and snow followed by rapid melt and night‐time freezing could have co‐triggered the slide. Additional seismic events with epicentres <40 km from the cirque were recorded 26 times since 1985 and range between ML 0·9–3·3, but none were caused by, or triggered, large mass movement.With a rock source volume of 1·6 × 106 m3 and a deposited volume of 2–4 × 106 m3 the sum of bulking and entrainment is between 25% and 150%. Five melt seasons post‐event, levees 20–30 m wide tower 30 m over the surrounding glacier. Rockslide characteristics, and its Fahrböschung of 15° [height/length (H/L) = 0·28], indicate that this rockslide is quite typical for long‐runout rockslides on glaciers. However, the basal friction coefficient was higher than found on other glaciers and could relate to the presence of medial moraines transverse to the flowline and to pre‐slide debris‐cover. The difference between the coefficient of friction in the main flowline (0·11–0·14) and that in a lobe confined between two medial moraines (0·065) suggests that confinement increases mobility by 70–115%. Apart from reduced ablation under the rock debris, effects of the rockslide on the glacier were minimal. Copyright © 2010 John Wiley & Sons, Ltd.
Policy challenges to the quality of child health services in Bulgaria
Authors: Rechel Boika , Spencer Nick , Blackburn Clare , Rechel Bernd 
Published: June 2010

AbstractBackgroundOur study aimed to explore policy challenges to the quality of child health services in Bulgaria.MethodsThe study was based on qualitative in‐depth interviews, analysis of regulatory documents, and review of the literature. Respondents included policy‐makers, providers and users of health services, from both rural and urban areas.ResultsProblems identified included insufficient training of general practitioners, medical errors, delays in response to emergencies, inadequate information provided to patients, and underdeveloped child public health. A common view was that paediatricians provide better quality care than general practitioners. Respondents described a lack of clinical guidelines for rational use of pharmaceuticals, overprescribing of antibiotics, reliance on pharmaceutical companies for information, and unrestricted sales of drugs over‐the‐counter. ‘Clinical pathways’, introduced as a payment mechanism in hospitals, were perceived as lacking transparency, complicating clinical practice, and forcing doctors to record wrong diagnoses and conduct unnecessary investigations.ConclusionsOur findings indicate the need to develop evidence‐based clinical guidelines for primary and secondary care, establish payment mechanisms that facilitate quality improvements, promote rational use of pharmaceuticals, improve continuing training of physicians and strengthen child public health. Copyright © 2010 John Wiley & Sons, Ltd.
The effect of location on finding a job in the Paris region
Authors: Gobillon Laurent , Magnac Thierry , Selod Harris 
Published: June 2010

AbstractDo spatial differences in unemployment duration reflect residential sorting or a true local effect? Focusing on the 1300 municipalities of the Paris region, we apply a methodology that disentangles individual and unspecified municipality effects. Estimating a proportional hazard model stratified by municipality and recovering a survival function for each municipality purged of individual observed heterogeneity, we show that local and individual characteristics add up in their contribution to unemployment duration. While only 30% of the spatial disparities in unemployment duration are explained by individual characteristics, 70% of the remaining disparities are captured by local indicators, mainly correlated with residential segregation. Copyright © 2010 John Wiley & Sons, Ltd.
Biodegradable xylitol‐based elastomers: In vivo behavior and biocompatibility
Authors: Bruggeman Joost P. , Bettinger Christopher J. , Langer Robert 
Published: June 2010

AbstractBiodegradable elastomers based on polycondensation reactions of xylitol with sebacic acid, referred to as poly(xylitol sebacate) (PXS) elastomers have recently been developed. We describe the in vivo behavior of PXS elastomers. Four PXS elastomers were synthesized, characterized, and compared with poly(L‐lactic‐co‐glycolic acid) (PLGA). PXS elastomers displayed a high level of structural integrity and form stability during degradation. The in vivo half‐life ranged from approximately 3 to 52 weeks. PXS elastomers exhibited increased biocompatibility compared with PLGA implants. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010
Development of a three‐dimensional model for rapid evaluation of bone substitutes in vitro: Effect of the 45S5 bioglass
Authors: Alno Nora , Jegoux Franck , Pellen‐Mussi Pascal , Tricot‐Doleux Sylvie , Oudadesse Hassane , Cathelineau Guy , De Mello Gilbert 
Published: June 2010

AbstractThe evaluation of innovative bone substitutes requires the development of an optimal model close to physiological conditions. An interesting alternative is the use of an immortalized cell line to construct multicellular spheroids, that is, three‐dimensional (3D) cultures. In this study, a modified hanging drops method has resulted in the generation of spheroids with a well‐established human fetal osteoblasts line (hFOB 1.19), and tests have been focused on the effect of 45S5 bioglass ionic dissolution products in comparison with two‐dimensional (2D) cultures. Depending on cell culture type, quantitative analysis (cell proliferation, viability/cytotoxicity, and cellular cycle) and qualitative analysis (electron microscopy and genes expression) showed a differential effect. Cell proliferation was enhanced in 2D‐conditioned cultures in accordance with literature data, but decreased in 3D cultures submitted to the same conditions, without change of gene expression patterns. The decrease of cell proliferation, observed in conditioned spheroids, appears to be in agreement with clinical observations showing the insufficiency of commercially available bioglasses for bone repairing within nonbearing sites, such as periodontal defects or small bone filling, in general. Therefore, we suggest that this model could be adapted to the screening of innovative bioactive materials by laboratory techniques already available and extended monitoring of their bioactivity. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.
Tailoring nanocrystalline diamond coated on titanium for osteoblast adhesion
Authors: Pareta Rajesh , Yang Lei , Kothari Abhishek , Sirinrath Sirivisoot , Xiao Xingcheng , Sheldon Brian W. , Webster Thomas J. 
Published: June 2010

AbstractDiamond coatings with superior chemical stability, antiwear, and cytocompatibility properties have been considered for lengthening the lifetime of metallic orthopedic implants for over a decade. In this study, an attempt to tailor the surface properties of diamond films on titanium to promote osteoblast (bone forming cell) adhesion was reported. The surface properties investigated here included the size of diamond surface features, topography, wettability, and surface chemistry, all of which were controlled during microwave plasma enhanced chemical‐vapor‐deposition (MPCVD) processes using CH4‐Ar‐H2 gas mixtures. The hardness and elastic modulus of the diamond films were also determined. H2 concentration in the plasma was altered to control the crystallinity, grain size, and topography of the diamond coatings, and specific plasma gases (O2 and NH3) were introduced to change the surface chemistry of the diamond coatings. To understand the impact of the altered surface properties on osteoblast responses, cell adhesion tests were performed on the various diamond‐coated titanium. The results revealed that nanocrystalline diamond (grain sizes <100 nm) coated titanium dramatically increased surface hardness, and the introduction of O2 and NH3 during the MPCVD process promoted osteoblast adhesion on diamond and, thus, should be further studied for improving orthopedic applications. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.
Synthesis of acrolein by gas‐phase dehydration of glycerol over silica supported Bronsted acidic ionic liquid catalysts
Authors: Munshi Mudassir K. , Lomate Samadhan T. , Deshpande Raj M. , Rane Vilas H. , Kelkar Ashutosh A. 
Published: June 2010

AbstractBACKGROUND: Glycerol has become readily available as a byproduct from the biodiesel industry. High functionality and relatively low price make it a potential building block to produce value‐added derivatives such as acrolein.RESULTS: Dehydration of glycerol to acrolein was performed over several silica supported Brønsted acidic ionic liquids as catalysts. All the catalysts prepared were active for the synthesis of acrolein (conversion of glycerol was observed in the range 35–90% with selectivity to acrolein in the range 29–58%).CONCLUSIONS: Catalyst prepared from triphenyl (3‐sulfopropyl) phosphonium 4‐methylbenzenesulfonate gave good activity and selectivity at 4 h reaction time. The conversion of glycerol decreased with increase in glycerol concentration. Higher temperature (325 °C) resulted in significantly lower conversion as well as selectivity to acrolein. With the use of two additional traps cooled to − 7 °C, the selectivity to acrolein increased significantly for good catalysts. Copyright © 2010 Society of Chemical Industry