bluuebunny/crossref_metadata_2025_split huggingface dataset:
Direct and indirect thermal expansion effects in turbulent premixed flames
Authors: Robin Vincent , Mura Arnaud , Champion Michel 
Published: December 2011

AbstractThe thermal expansion induced by the exothermic chemical reactions taking place in a turbulent reactive flow affects the velocity field so strongly that the large-scale velocity fluctuations as well as the small-scale velocity gradients can be governed by chemistry rather than by turbulence. Moreover, thermal expansion is well known to be responsible for counter-gradient turbulent diffusion and flame-generated turbulence phenomena. In the present study, by making use of an original splitting procedure applied to the velocity field, we establish the occurrence of two distinct thermal expansion effects in the flamelet regime of turbulent premixed combustion. The first is referred to as the direct thermal expansion effect. It is associated with a local flamelet crossing contribution as previously considered in early analyses of turbulent transport in premixed flames. The second, denoted herein as the indirect thermal expansion effect, is an outcome of the turbulent wrinkling processes that increases the flame surface area. Based on a splitting procedure applied to the velocity field, the respective influences of the two effects are identified and analysed. Furthermore, the theoretical analysis shows that the thermal expansion induced through the local flames can be treated separately in the usual continuity and momentum equations. This description of the turbulent reactive velocity field, leads also to relate all of the usual turbulent quantities to the reactive scalar field. Finally, algebraic closures for the turbulent transport terms of mass and momentum are proposed and successfully validated through comparison with direct numerical simulation data.
Effects of flexibility on the aerodynamic performance of flapping wings
Authors: Kang C.-K. , Aono H. , Cesnik C. E. S. , Shyy W. 
Published: December 2011

AbstractEffects of chordwise, spanwise, and isotropic flexibility on the force generation and propulsive efficiency of flapping wings are elucidated. For a moving body immersed in viscous fluid, different types of forces, as a function of the Reynolds number, reduced frequency (k), and Strouhal number (St), acting on the moving body are identified based on a scaling argument. In particular, at the Reynolds number regime of$O(1{0}^{3} \ensuremath{-} 1{0}^{4} )$and the reduced frequency of$O(1)$, the added mass force, related to the acceleration of the wing, is important. Based on the order of magnitude and energy balance arguments, a relationship between the propulsive force and the maximum relative wing-tip deformation parameter ($\gamma $) is established. The parameter depends on the density ratio,St,k, natural and flapping frequency ratio, and flapping amplitude. The lift generation, and the propulsive efficiency can be deduced by the same scaling procedures. It seems that the maximum propulsive force is obtained when flapping near the resonance, whereas the optimal propulsive efficiency is reached when flapping at about half of the natural frequency; both are supported by the reported studies. The established scaling relationships can offer direct guidance for micro air vehicle design and performance analysis.
Association of vitamin K status with adiponectin and body composition in healthy subjects: uncarboxylated osteocalcin is not associated with fat mass and body weight
Authors: Knapen Marjo H. J. , Schurgers Leon J. , Shearer Martin J. , Newman Paul , Theuwissen Elke , Vermeer Cees 
Published: December 2011

Osteocalcin (OC) is a vitamin K-dependent protein found in bone and in circulation. High serum γ-carboxylated OC reflects a high, and high uncarboxylated OC (ucOC) reflects a low vitamin K status. A revolutionary hypothesis is that ucOC acts as a hormone improving glucose handling and reducing fat mass. The objective was to test the logical extrapolation of the ucOC hormone hypothesis to humans that elevated ucOC is associated with higher body weight, BMI and fat mass. In a cross-sectional analysis, the associations of vitamin K status with circulating adiponectin and body composition were investigated in 244 postmenopausal women (study I). The effects of vitamin K treatment on adiponectin, body weight and BMI were investigated in archived samples from forty-two young men and women who received varying doses of menaquinone-7 during 12 weeks (study II) and from a cohort of 164 postmenopausal women who participated in a 3-year placebo-controlled trial on 45 mg menaquinone-4 (MK-4) (study III). No association was found between vitamin K status and circulating adiponectin before or after vitamin K supplementation. A higher carboxylation of OC was significantly correlated with lower body weight, BMI and fat mass of the trunk. Women taking MK-4 maintained their baseline body weight and BMI, whereas women taking placebo showed significant increases in both indices. These findings demonstrate that a high vitamin K status of bone has no effect on circulating adiponectin in healthy people and long-term vitamin K supplementation does not increase weight in healthy postmenopausal women.
The precipitous decline of the ortolan buntingEmberiza hortulana: time to build on scientific evidence to inform conservation management
Authors: Menz Myles H. M. , Arlettaz Raphaël 
Published: December 2011

AbstractIn recent decades there has been a marked decline in most ortolan buntingEmberiza hortulanapopulations in temperate Europe, with many regional populations now extinct or on the brink of extinction. In contrast, Mediterranean and, as far as we know, eastern European popula-tions seem to have remained relatively stable. The causes of decline remain unclear but include: habitat loss and degradation, and related reduction in prey availability; climate change on the breeding grounds; altered population dynamics; illegal captures during migration; and environmental change in wintering areas. We review the current knowledge of the biology of the ortolan bunting and discuss the proposed causes of decline in relation to the different population trends in temperate and Mediterranean Europe. We suggest new avenues of research to identify the factors limiting ortolan bunting populations. The main evidence-based conservation measure that is likely to enhance habitat quality is the creation of patches of bare ground to produce sparsely vegetated foraging grounds in invertebrate-rich grassy habitats close to breeding areas.
Lower birth weight indicates higher risk of autistic traits in discordant twin pairs
Authors: Losh M. , Esserman D. , Anckarsäter H. , Sullivan P. F. , Lichtenstein P. 
Published: December 2011

BackgroundAutism spectrum disorder (ASD) is a neurodevelopmental disorder of complex etiology. Although strong evidence supports the causal role of genetic factors, environmental risk factors have also been implicated. This study used a co-twin–control design to investigate low birth weight as a risk factor for ASD.MethodWe studied a population-based sample of 3715 same-sex twin pairs participating in the Child and Adolescent Twin Study of Sweden (CATSS). ASD was assessed using a structured parent interview for screening of ASD and related developmental disorders, based on DSM-IV criteria. Birth weight was obtained from medical birth records maintained by the Swedish Medical Birth Registry.ResultsTwins lower in birth weight in ASD-discordant twin pairs (n=34) were more than three times more likely to meet criteria for ASD than heavier twins [odds ratio (OR) 3.25]. Analyses of birth weight as a continuous risk factor showed a 13% reduction in risk of ASD for every 100 g increase in birth weight (n=78). Analysis of the effect of birth weight on ASD symptoms in the entire population (most of whom did not have ASD) showed a modest association. That is, for every 100 g increase in birth weight, a 2% decrease in severity of ASD indexed by scores on the Autism – Tics, attention-deficit hyperactivity disorder (AD/HD), and other Comorbidities (A-TAC) inventory would be expected in the sample as a whole.ConclusionsThe data were consistent with the hypothesis that low birth weight confers risk to ASD. Thus, although genetic effects are of major importance, a non-genetic influence associated with birth weight may contribute to the development of ASD.
Fishery Support Ships
Authors: Dinsdale Tom , Scott Robert Weden 
Published: December 2011

SynopsisThe authors have served in both Fishery Support Ships Orsino and Miranda, operated by the Board of Trade following the trawler losses in 1968.They describe the history of the British Mission Ships first operated 90 years ago, as well as the origins of the Dutch and Portuguese services.A detailed description is given of the events leading up to, and some experiences of, the present British service.Finally, an account is presented of the services provided by some other maritime powers.
The Transport of Organic Carbon to Organisms living in the Deep Oceans.
Authors: Fournier Robert O. 
Published: December 2011

SynopsisNumerous theories exist to explain the mechanism of transport of organic carbon from its site of photosynthetic fixation to the point of its utilisation in the deep ocean. With one exception none has been adequately quantified. A new mechanism is proposed which suggests that the so-called olivegreen cells may contribute up to 35 per cent, of the carbon requirements of the benthic fauna. These conclusions are based on observations of their vertical distribution, the apparent labile nature of these cells and evidence of their presence in the guts of benthic and pelagic fauna.
Fluctuation and natural control of animal population, as exemplified in the garden chaferPhyllopertha horticola(L.)
Authors: Milne A. 
Published: December 2011

SynopsisThe garden chafer.Phyllopertha horticola(L.), renews its population every June. Its numbers fluctuate irregularly from year to year. During 1947 75 in the English Lake District, it had two ‘outbreaks’ (with peaks in 1952 and 1975) separated by a long period of low population (1956–70). In nine of the years 1948 75, October population increased significantly over that of the preceding year: in eleven, it did not change significantly; and in ihe remaining eight, it decreased significantly. These fluctuations in numbers were due to fluctuations in the effective environmental factors (weather, enemies and intraspecific competition) influencing sun ival, fecundity and migration. Weather was more effective than enemies in this respect and intraspecific competition became important only when weather and enemies together failed to keep numbers from rising dangerously high for the chafer. Weather was, of course, density-independent in action. Among enemies, interspecific competitors were density-independent while pathogens, parasites and predators were all imperfectly density-dependent. The only perfectly density-dependent factor was intraspecific competition. These findings bear out Milne's theory (1957aet seq.) that for part of the time, natural control of population increase of any species X is due to the combined action of density-independent and imperfectly density-dependent environmental factors but, whenever this combined action fails (as inevitably it sometimes must), increase to the point of collective suicide is prevented by the one and only perfectly density-dependent factor, namely, intraspecific competition of X; on the other hand, decrease of numbers of X to zero is prevented ultimately by density-independent factors alone.
Sediments of the Tay Estuary. I. Bottom Sediments of the Upper and Upper Middle Reaches
Authors: Buller A. T. , McManus J. 
Published: December 2011

SynopsisA lack of modern river-borne sediment and a steady supply of marine materials have led to the hypothesis that the upper Tay estuary is undergoing an erosive phase counterbalanced by a headward moving sheet of largely marine-derived sand presently occupying the upper-middle estuary. This primal division (based on sediment budget criteria) is also reflected in the bathymetry, distribution of sediment types, and sedimentary structures. The situation of two contrasting ‘phase zones’ juxtaposed within a relatively small area is ideal for an empirical and indirect analysis of the response of a wide variety of sediment types to the gross physical processes acting on them. The analysis takes the form of standard grain-size characterisations using conventional sedimentary statistics, supplemented by adaptations of C-M and QDa-Md diagrams transformed for display on distribution maps.
Sediments of the Tay Estuary. II. Formation of Ephemeral Zones of High Suspended Sediment Concentrations.
Authors: Buller A. T. 
Published: December 2011

SynopsisDuring periods of sustained moderate river discharge and quiescent marine conditions little external suspended sediment enters the estuarine circulation of the Tay. That material which is in suspension is largely derived from the estuary margins where tidal currents superimposed by wind-induced waves are competent to resuspend fine material from the surface of the ‘mud’ flats and erode bedded silts from the incised banks of minor channels and runnels draining them. The quantities of this sediment entering the system are largely determined by tidal state and amplitude, as well as wind velocity.On spring tides the flats are entirely covered at high water, and dry out completely at low water. The volume of water and its areal coverage at high tide ensures that, during the ebb, water charged with high concentrations of suspended sediment is directed from the fiats into the surface and middepth waters of the main channel. This process acting along the 20 km length of the channel flanking the ‘mud’ flats, combined with the low tide ‘ponding effect’ caused by the tide flooding from the sea while the upper estuarine water is still ebbing, results in the cumulative formation of a zone of high suspended sediment concentrations (turbidity maximum). As the flood tide becomes fully established the zone is diluted and dispersed. During neap tides the same processes operate, but because a smaller area of the flats is covered at high water and uncovered at low water, and because neap tidal current speeds are lower than those for spring tides, two proportionally weaker zones are recognised.Following periods of sustained moderate river discharge, quiet sea conditions and calm weather, suspended sediment concentrations in the Tay are negligible irrespective of tidal state or amplitude.
Sediments of the Tay Estuary. III. Sedimentological and Faunal Relationships on the Southern Shore at the Entrance to the Tay.
Authors: Green Christopher D. 
Published: December 2011

SynopsisThe southern entrance shores to the Tay estuary form an area of extensive inter-tidal sedimentation. Tidal currents of varying strengths characterise the area and the situation is modified by both wind and wave. The net result is a series of seven sub-environments of sedimentation. The textural characteristics of the sediment and the distribution of major and minor sedimentary structures in each subenvironment is closely linked to stability and changing physical processes. The distribution of organisms, live and dead, provides a good indication of these patterns of sediment and stability.
Endocrine Aspects of Salmonid Culture
Authors: Simpson T. H. 
Published: December 2011

SYNOPSISAdministration, by dietary supplement, of ethylestrenol to rainbow trout and to salmon parr results in significant increases in growth rate; further treatment of smolts retained in fresh water reduces the growth rate. Treated parr develop into 1 + smolts in significantly lower proportion than controls, but have a higher condition factor.Stress induces in rainbow trout long-lasting reductions in plasma thyroxine levels and increases in serum cortisol concentrations. The origin and significance of these changes is discussed.The administration of 17β-oestradiol at 20 mg/kg of food for the first 30 days of feeding causes sex-reversal of male salmonids. Treatment with 17α-methyltestosterone at 3 mg/kg food for 90 days following first-feeding causes sex-reversal of female salmonids.
The impacts of La Niña-induced drought on Indian Vulture Gyps indicus populations in Western Rajasthan
Authors: HALL JONATHAN C. , CHHANGANI ANIL K. , WAITE TOM A. , HAMILTON IAN M. 
Published: December 2011

SummaryPrevious research on the catastrophic decline of the Gyps species complex has identified diclofenac, a non-steroidal anti-inflammatory drug administered to livestock, as the primary cause. Large-scale climatic phenomena, such as ENSO-induced drought, however have not been examined. Based on time series analysis of annual count data, 1996–2005, we provide evidence that ENSO synchronised population dynamics throughout western Rajasthan. Here, we ask whether El Niño Southern Oscillation (ENSO) can also explain the population dynamics of the Critically Endangered Indian Vulture Gyps indicus. We attribute this impact largely to two La Niña events, including the major event spanning 1999. We also examine between-village variation in resident vulture populations. Our results suggest that in several villages, Indian Vulture populations may have been partially buffered from the negative effects of drought when compared to other villages in the study. Finally, we discuss potential causes of buffering in these villages.
NUMERICAL SIMULATION OF MHD STAGNATION POINT FLOW TOWARDS A HEATED AXISYMMETRIC SURFACE
Authors: ASHRAF MUHAMMAD , ANWAR KAMAL M. 
Published: December 2011

AbstractThe problem of stagnation point flow with heat transfer of an electrically conducting fluid impinging normally on a permeable axisymmetric surface in the presence of a uniform transverse magnetic field is analysed. The governing nonlinear differential equations and their associated boundary conditions are reduced to dimensionless form using suitable similarity transformations. Comparison with previously published work shows good agreement. Effects of the injection–suction parameter, magnetic parameter and Prandtl number on the flow and thermal fields are presented. The investigations show that the wall shear stress and heat transfer rate from the surface increase with increased applied magnetic field. An increase in the velocity and thermal boundary layer thicknesses is observed with an increase in the wall injection, while the velocity and thermal boundary layers become thinner when increasing the wall suction and applied magnetic field.
AGN and Host Galaxies in the COSMOS Survey
Authors: Impey Christopher D. , Trump Jonathan R. , Gabor Jared M. ,   the COSMOS team
Published: December 2011

AbstractThe Cosmological Evolution Survey (COSMOS) is a unique tool for studying low level AGN activity and the co-evolution of galaxies and supermassive black holes. COSMOS involves the largest contiguous region of the sky ever imaged by HST; it includes very complete multiwavelength coverage, and the largest joint samples of galaxy and AGN redshifts in any deep survey. The result is a search for AGN with low black hole mass, low accretion rates, and levels of obscuration that can remove them from optical surveys. A complete census of intermediate mass black holes at redshifts of 1 to 3 is required to tell the story of the co-evolution of galaxies and their embedded, and episodically active, black holes.
The Westerbork HALOGAS Survey: Status and Early Results
Authors: Heald George , Allan John , Zschaechner Laura , Kamphuis Peter , Rand Rich , Józsa Gyula , Gentile Gianfranco 
Published: December 2011

AbstractWe present early results from the ongoing Hydrogen Accretion in LOcal GAlaxieS (HALOGAS) Survey, which is being performed with the Westerbork Synthesis Radio Telescope (WSRT). The HALOGAS Survey aims to detect and characterize the cold gas accretion process in nearby spirals, through sensitive observations of neutral hydrogen (Hi) 21-cm line emission. In this contribution, we present an overview of ongoing analyses of several HALOGAS targets.
What Radio Astronomy Can Tell us about Galaxy Formation
Authors: Partridge Bruce 
Published: December 2011

AbstractRadio astronomy, broadly interpreted, has made important contributions to the study of galaxy formation and evolution. Maps of the cosmic microwave background provide information on the seeds of large-scale structure, in addition to refined values of the cosmological parameters. Examples of contributions from more conventional radio astronomy include:–The use of radio observations to track star formation rates since they are not affected by dust obscuration as optical/UV observations are, and the use of molecular line observations to make purely “radio” redshift determinations.
Comparisons of CO and HI Dynamics in THINGS Galaxies
Authors: Frank Bradley S. , de Blok W. J. G. ,   the HERACLES Team
Published: December 2011

AbstractWe present recent results comparing the CO and HI dynamics of nearby galaxies that have been observed as part of the THINGS (HI) and the HERACLES (CO) surveys. We focus on 3 galaxies out of the 11 that have been analysed so far, and present velocity-fields and rotation curves of the CO, which we compare with that of the HI.
Reconstruction of Star Formation and AGNs Activities in Galaxies Classified with the Balmer Break, 1.6 μm Bump and PAH Features up to z ≃2
Authors: Hanami Hitoshi , Ishigaki Tsuyoshi ,   AKARI Extragalactic Team
Published: December 2011

AbstractWe have studied the star-forming and AGN activity of massive galaxies in the redshift range z = 0.4−2, which are detected in a deep survey field using the AKARI and Subaru telescopes toward the North Ecliptic Pole (NEP). The multi-wavelength survey allows us to select Mid-InfraRed (MIR) bright populations as Luminous InfraRed Galaxies (LIRGs) with L(IR) ≃ 1010–11 L⊙, which can be also sub-classified into Balmer Break Galaxies (BBGs) and Infra-Red (IR) Bump Galaxies (IRBGs). AKARI/IRC multiband photometry can distinguish their star-forming/AGN activity for LIRGs with/without the Polycyclic-Aromatic Hydrocarbon (PAH) emission bands at 6.2, 7.7 and 11.3 μm, and estimate the Star Formation Rate (SFR) from their total emitting InfraRed (IR) luminosities for star-formings and the emissions from dusty torus for AGNs. The results are summarised as below: 1) The rest-frame 7.7 μm luminosity is still a good tracer of the total IR (tIR) luminosity, as the PAH emission dominates for star-forming galaxies even up to z ≃ 2, 2) Rest-frame 5μm Luminosities may trace emissions from dusty torus of AGN in the LIRGs, 3) SFR of Starburst-AGN LIRGs (s/a-LIRGs) tends to quench at z < 0.8 more rapidly than that of Starburst dominated LIRGs (sb-LIRGs), 4) Intrinsic Stellar populations in the s/a-LIRGs show redder colours than those in the sb-LIRGs. These results suggest that Super Massive Black Holes (SMBH) could already have grown to ≃ 3 × 108M⊙ in the agn-LIRGs, with ≃ 1011L⊙ at z > 1.2, and the growth of SMBH tends to follow the star-forming activities around z = 1–2.
The Virtual Observatory Data, Standards and Tools a technical - user point of view
Authors: Surace Christian ,   the CeSAM team
Published: December 2011

AbstractIn 2002 the International Virtual Observatory Alliance (IVOA) has been created in order to gather efforts on data standardization and dissemination. Since then, the virtual Observatory allowed to spread validated data all over the world and to use data from everywhere from earth. From the standards definitions to development of tools, developers have set up a technical infrastructure used by astronomers to easily search for data and make science with all available products, more tools and more confidence on the quality of data. The goal of this review is to present the state of the art of the VO data, standards and tools. This review focuses on basic astronomer's questions : what kind of data are accessible, how to deal with these data and how to use them.