bluuebunny/crossref_metadata_2025 huggingface dataset:
The Spanish Civil War and the British Labour Movement
Authors: Buchanan Tom
Published: January 2012

This book draws on a mass of documentary material to provide a major reinterpretation of British labour's response to the Spanish Civil War. It challenges the view that the labour leadership ' betrayed' the Spanish Republic, and that this polarised the movement along `left' versus 'right' lines. Instead, it argues that the overriding concern of the major leaders was to defend labour's institutional interests against the political destabilisation caused by the conflict, rather than to defend Spanish democracy. Although the main advocates of this position were trade union leaders associated with the labour right such as Walter Citrine and Ernest Bevin, the book argues that their dominance reflected the centrality of the trade unions to labour movement decision-making rather than the abuse of union power to achieve political goals.
Print Culture in Early Modern France
Authors: Goldstein Carl
Published: January 2012

In this book, Carl Goldstein examines the print culture of seventeenth-century France through a study of the career of Abraham Bosse, a well-known printmaker, book illustrator, and author of books and pamphlets on a variety of technical subjects. The consummate print professional, Bosse persistently explored the endless possibilities of print – single-sheet prints combining text and image, book illustration, broadsides, placards, almanacs, theses, and pamphlets. Bosse had a profound understanding of print technology as a fundamental agent of change. Unlike previous studies, which have largely focused on the printed word, this book demonstrates the extent to which the contributions of an individual printmaker and the visual image are fundamental to understanding the nature and development of early modern print culture.
Empirical Social Choice
Authors: Gaertner Wulf , Schokkaert Erik
Published: January 2012

Since Aristotle, many different theories of distributive justice have been proposed, by philosophers as well as social scientists. The typical approach within social choice theory is to assess these theories in an axiomatic way – most of the time the reader is confronted with abstract reasoning and logical deductions. This book shows that empirical insights are necessary if one wants to apply any theory of justice in the real world. It does so by confronting the main theories of distributive justice with data from (mostly) questionnaire experiments. The book starts with an extensive discussion on why empirical social choice makes sense and how it should be done. It then presents various experimental results relating to theories of distributive justice, including the Rawlsian equity axiom, Harsanyi's version of utilitarianism, utilitarianism with a floor, responsibility-sensitive egalitarianism, the claims problem and fairness in health.
The Mechanics of the Circulation
Authors: Caro C. G. , Pedley T. J. , Schroter R. C. , Seed W. A. , Parker K. H.
Published: January 2012

Continuing demand for this book confirms that it remains relevant over 30 years after its first publication. The fundamental explanations are largely unchanged, but in the new introduction to this second edition the authors are on hand to guide the reader through major advances of the last three decades. With an emphasis on physical explanation rather than equations, Part I clearly presents the background mechanics. The second part applies mechanical reasoning to the component parts of the circulation: blood, the heart, the systemic arteries, microcirculation, veins and the pulmonary circulation. Each section demonstrates how an understanding of basic mechanics enhances our understanding of the function of the circulation as a whole. This classic book is of value to students, researchers and practitioners in bioengineering, physiology and human and veterinary medicine, particularly those working in the cardiovascular field, and to engineers and physical scientists with multidisciplinary interests.
Introduction to Compact Riemann Surfaces and Dessins d’Enfants
Authors: Girondo Ernesto , González-Diez Gabino
Published: January 2012

Few books on the subject of Riemann surfaces cover the relatively modern theory of dessins d'enfants (children's drawings), which was launched by Grothendieck in the 1980s and is now an active field of research. In this 2011 book, the authors begin with an elementary account of the theory of compact Riemann surfaces viewed as algebraic curves and as quotients of the hyperbolic plane by the action of Fuchsian groups of finite type. They then use this knowledge to introduce the reader to the theory of dessins d'enfants and its connection with algebraic curves defined over number fields. A large number of worked examples are provided to aid understanding, so no experience beyond the undergraduate level is required. Readers without any previous knowledge of the field of dessins d'enfants are taken rapidly to the forefront of current research.
Religion-State Relations in the United States and Germany
Authors: Haupt Claudia E.
Published: January 2012

This comparative analysis of the constitutional law of religion-state relations in the United States and Germany focuses on the principle of state neutrality. A strong emphasis on state neutrality, a notoriously ambiguous concept, is a shared feature in the constitutional jurisprudence of the US Supreme Court and the German Federal Constitutional Court, but neutrality does not have the same meaning in both systems. In Germany neutrality tends to indicate more distance between church and state, whereas the opposite is the case in the United States. Neutrality also has other meanings in both systems, making straightforward comparison more difficult than it might seem. Although the underlying trajectory of neutrality is different in both countries, the discussion of neutrality breaks down into largely parallel themes. By examining those themes in a comparative perspective, the meaning of state neutrality in religion-state relations can be delineated.
Trapped modes and Fano resonances in two-dimensional acoustical duct–cavity systems
Authors: Hein Stefan , Koch Werner , Nannen Lothar
Published: January 2012

Revisiting the classical acoustics problem of rectangular side-branch cavities in a two-dimensional duct of infinite length, we use the finite-element method to numerically compute the acoustic resonances as well as the sound transmission and reflection for an incoming fundamental duct mode. To satisfy the requirement of outgoing waves in the far field, we use two different forms of absorbing boundary conditions, namely the complex scaling method and the Hardy space method. In general, the resonances are damped due to radiation losses, but there also exist various types of localized trapped modes with nominally zero radiation loss. The most common type of trapped mode is antisymmetric about the duct axis and becomes quasi-trapped with very low damping if the symmetry about the duct axis is broken. In this case a Fano resonance results, with resonance and antiresonance features and drastic changes in the sound transmission and reflection coefficients. Two other types of trapped modes, termed embedded trapped modes, result from the interaction of neighbouring modes or Fabry–Pérot interference in multi-cavity systems. These embedded trapped modes occur only for very particular geometry parameters and frequencies and become highly localized quasi-trapped modes as soon as the geometry is perturbed. We show that all three types of trapped modes are possible in duct–cavity systems and that embedded trapped modes continue to exist when a cavity is moved off centre. If several cavities interact, the single-cavity trapped mode splits into several trapped supermodes, which might be useful for the design of low-frequency acoustic filters.
Experiments on the periodic oscillation of free containers driven by liquid sloshing
Authors: Herczyński Andrzej , Weidman Patrick D.
Published: January 2012

Experiments on the time-periodic liquid sloshing-induced sideways motion of containers are presented. The measurements are compared with finite-depth potential theory developed from standard normal mode representations for rectangular boxes, upright cylinders, wedges and cones of$9{0}^{\ensuremath{\circ} } $apex angles, and cylindrical annuli. It is assumed that the rectilinear horizontal motion of the containers is frictionless. The study focuses on measurements of the horizontal oscillations of these containers arising solely from the liquid waves excited within. While the wedge and cone exhibit only one mode of oscillation, the boxes, cylinders and annuli have an infinite number of modes. For the boxes, cylinders and one of the annuli, we have been able to excite motion and record data for both the first and second modes of oscillation. Frequencies$\omega $were acquired as the average of three experimental determinations for every filling of mass$m$in the dry containers of mass${m}_{0} $. Measurements of the dimensionless frequencies$\omega / {\omega }_{R} $over a range of dimensionless liquid masses$M= m/ {m}_{0} $are found to be in essential agreement with theoretical predictions. The frequencies${\omega }_{R} $used for normalization arise naturally in the mathematical analysis, different for each geometry considered. Free surface waveforms for a box, a cylinder, the wedge and the cone are compared at a fixed value of$M$.
Numerical simulation of flow past a heated/cooled sphere
Authors: Kurose Ryoichi , Anami Mamiko , Fujita Akitoshi , Komori Satoru
Published: January 2012

The characteristics of flow past a heated/cooled sphere are investigated for particle Reynolds numbers $50\leq {\mathit{Re}}_{p} \leq 500$ in conditions with and without buoyancy by means of three-dimensional numerical simulation in which temperature dependence of fluid properties such as density and viscosity is exactly taken into account. The results show that in the absence of buoyancy, drag coefficients of the heated and cooled spheres are larger and smaller than those of the adiabatic case, respectively, and their Nusselt numbers are smaller and larger than the values estimated by a widely used empirical expression for predicting Nusselt numbers, respectively. In addition, the temperature difference between the sphere and ambient fluid strongly affects the flow separation points, size of vortex ring behind the sphere and Strouhal number for vortex shedding. These changes are attributed to the temperature dependence of fluid properties in the vicinity of the sphere. Even in the presence of buoyancy, the temperature dependence of fluid properties strongly affects the drag coefficient and Nusselt number and therefore the Boussinesq approximation becomes inapplicable as the temperature difference increases, regardless of the magnitude of the Richardson number.
Dietary inclusion of salmon, herring and pompano as oily fish reduces CVD risk markers in dyslipidaemic middle-aged and elderly Chinese women
Authors: Zhang Jian , Wang Chunrong , Li Lixiang , Man Qingqing , Meng Liping , Song Pengkun , Frøyland Livar , Du Zhen-Yu
Published: January 2012

Dietary intervention studies to assess the cardioprotective effects of oily fish are scarce in China. The present study aimed to examine the effects of the oily fish, Norwegian salmon, herring and local farmed pompano (Trachinotus ovatus) on CVD risk markers when included in the Chinese diet. In this 8-week, parallel-arm, randomised intervention study, 126 Chinese women with hypertriacylglycerolaemia, aged 35–70 years, were assigned to four groups to consume an experimental lunch containing 80 g fillets of either one of three oily fish or a mix of commonly eaten meats (pork/chicken/beef/lean fish) for 5 d/week. The results showed that inclusion of the three oily fish significantly increased the intake ofn-3 long-chain PUFA (LC-PUFA) while decreasing the dietaryn-6:n-3 PUFA ratio. Compared to the control group, significant increases of DHA, EPA+DHA and totaln-3 PUFA in plasma choline phosphoglyceride were observed in the three oily fish groups. Plasma TAG levels were significantly reduced only in the salmon and herring groups. When compared to the baseline level, the three oily fish diets significantly decreased serum concentrations of TAG, apoB, apoCII and apoCIII, but only the salmon and herring diets significantly lowered TNF-α and raised adiponectin levels in serum. The salmon diet additionally decreased the serum concentration of IL-6. To conclude, dietary inclusion of salmon, herring and pompano as oily fish can effectively increase serumn-3 LC-PUFA content and are associated with favourable biochemical changes in dyslipidaemic middle-aged and elderly Chinese women, and these beneficial effects are mainly associated withn-3 LC-PUFA contents.
Asparagus officinalis extract controls blood glucose by improving insulin secretion and β-cell function in streptozotocin-induced type 2 diabetic rats
Authors: Hafizur Rahman Md. , Kabir Nurul , Chishti Sidra
Published: January 2012

The aim of the present study was to evaluate the anti-diabetic mechanism of Asparagus officinalis, a dietary agent used for the management of diabetes. Streptozotocin (90 mg/kg) was injected in 2-d-old Wistar rat pups to induce non-obese type 2 diabetes. After confirmation of diabetes on the 13th week, diabetic rats were treated with a methanolic extract of A. officinalis seeds (250 and 500 mg/kg per d) or glibenclamide for 28 d. After the treatment, fasting blood glucose, serum insulin and total antioxidant status were measured. The pancreas was examined by haematoxylin–eosin staining and immunostained β- and α-cells were observed using a fluorescence microscope. Treatment of the diabetic rats with the A. officinalis extract at doses of 250 and 500 mg/kg suppressed the elevated blood glucose in a dose- and time-dependent manner. The 500 mg/kg, but not 250 mg/kg, dose significantly improved serum insulin levels in the diabetic rats. The insulin:glucose ratio was significantly increased at both doses in the A. officinalis-treated rats. Both qualitative and quantitative improvements in β-cell function were found in the islets of the A. officinalis-treated rats. The extract showed potent antioxidant activity in an in vitro assay and also improved the total antioxidant status in vivo. In most cases, the efficacy of A. officinalis (500 mg/kg) was very similar to a standard anti-diabetic drug, glibenclamide. Thus, the present study suggests that A. officinalis extract exerts anti-diabetic effects by improving insulin secretion and β-cell function, as well as the antioxidant status.
Coalescence, torus formation and breakup of sedimenting drops: experiments and computer simulations
Authors: MACHU GUNTHER , MEILE WALTER , NITSCHE LUDWIG C. , SCHAFLINGER UWE
Published: January 2012

The motion and shape evolution of viscous drops made from a dilute suspension of
tiny, spherical glass beads sedimenting in an otherwise quiescent liquid is investigated
both experimentally and theoretically for conditions of low Reynolds number. In
the (presumed) absence of any significant interfacial tension, the Bond number
[Bscr ] = (Δρ)gR2/σ is effectively infinite.
The key stages of deformation of single drops and
pairs of interacting drops are identified. Of particular interest are (i) the coalescence of
two trailing drops, (ii) the subsequent formation of a torus, and (iii) the breakup of the
torus into two or more droplets in a repeating cascade. To overcome limitations of the
boundary-integral method in tracking highly deformed interfaces and coalescing and
dividing drops, we develop a formal analogy between drops of homogeneous liquid
and a dilute, uniformly distributed swarm of sedimenting particles, for which only
the 1/r far-field hydrodynamic interactions are important. Simple, robust numerical
simulations using only swarms of Stokeslets reproduce the main phenomena observed
in the classical experiments and in our flow-visualization studies. Detailed particle
image velocimetry (PIV) for axisymmetric configurations enable a mechanistic analysis
and confirm the theoretical results. We expose the crucial importance of the initial
condition – why a single spherical drop does not deform substantially, but a pair
of spherical drops, or a bell-shaped drop similar to what is actually formed in the
laboratory, does undergo the torus/breakup transformation. The extreme sensitivity
of the streamlines to the shape of the ring-like swarm explains why the ring that
initially forms in the experiments does not behave like the slender open torus analysed
asymptotically by Kojima, Hinch & Acrivos (1984). Essentially all of the phenomena
described above can be explained within the realm of Stokes flow, without resort to
interfacial tension or inertial effects.
Prosorhynchoides borealis Bartoli, Gibson & Bray, 2006 (Digenea: Bucephalidae) cercariae from Abra prismatica (Mollusca: Bivalvia) in Icelandic waters
Authors: Eydal M. , Freeman M.A. , Kristmundsson Á. , Bambir S.H. , Jónsson P.M. , Helgason S.
Published: January 2012

This paper reports the adult stage of Prosorhynchoides borealis (Digenea) from Lophius piscatorius in Icelandic waters and infections with the larval stages (sporocysts and cercariae) found for the first time in the bivalve Abra prismatica (Semelidae). The previously known first intermediate host was Abraalba (Semelidae). Ribosomal DNA sequencing studies on all three life stages of the parasite (cercariae, metacercariae, adults) were performed to confirm their identites. Morphometric measurements confirmed that the adult worms belong to the newly described species P. borealis. Prosorhynchoides borealis sporocysts filled with cercariae were found in 16% of A. prismatica bivalves sampled at depths between 34 and 93 m off South Iceland. Prevalence ranged from 0 to 44% between different localities. The parasite was found only in the larger bivalves. Extensive sporocyst infection in the haemocoel of the foot caused mechanical muscle damage with subsequent degeneration and necrosis. Other tissues, including the digestive gland, nephridia, gills and intestine, were less heavily infected. Only focal necrosis was observed in the digestive gland, nephridia and gills, and local atrophy in the intestine. Cercariae were also observed in the lumen of both the stomach and intestine. This is the first report of A. prismatica as an alternative first intermediate host for P. borealis. Ribosomal DNA sequence data reveals 100% homology in the data between cercariae, metacercariae and adult digeneans, supporting the morphological data suggesting that all stages belong to the same species.
Compositional and phylogenetic dissimilarity of host communities drives dissimilarity of ectoparasite assemblages: geographical variation and scale-dependence
Authors: KRASNOV BORIS R. , MOUILLOT DAVID , KHOKHLOVA IRINA S. , SHENBROT GEORGY I. , POULIN ROBERT
Published: January 2012

We tested the hypothesis that compositional and/or phylogenetic dissimilarity of host assemblages affect compositional and/or phylogenetic dissimilarity of parasite assemblages, to different extents depending on scale, using regional surveys of fleas parasitic on small mammals from 4 biogeographical realms. Using phylogenetic community dissimilarity metric, we calculated the compositional and phylogenetic dissimilarity components between all pairs of host and parasite communities within realms and hemispheres. We then quantified the effect of compositional or phylogenetic dissimilarity in host regional assemblages, and geographical distance between assemblages, on the compositional or phylogenetic dissimilarity of flea regional assemblages within a realm, respectively. The compositional dissimilarity in host assemblages strongly affected compositional dissimilarity in flea assemblages within all realms and within both hemispheres. However, the effect of phylogenetic dissimilarity of host assemblages on that of flea assemblages was mostly confined to the Neotropics and Nearctic, but was detected in both the Old and New World at the higher scale, possibly because of phylogenetic heterogeneity in flea and host faunas between realms. The clearer effect of the compositional rather than the phylogenetic component of host community dissimilarity on flea community dissimilarity suggests important roles for host switching and ecological fitting during the assembly history of flea communities.
The Discursive Turn in Policy Analysis and the Validation of Policy Stories
Authors: PRIOR LINDSAY , HUGHES DAVID , PECKHAM STEPHEN
Published: January 2012

This paper is concerned with the language of policy documents in the field of health care, and how ‘readings’ of such documents might be validated in the context of a narrative analysis. The substantive focus is on a comparative study of UK health policy documents (N= 20) as produced by the various assemblies, governments and executives of England, Scotland, Wales and Northern Ireland during the period 2000–09. Following the identification of some key characteristics of narrative structure the authors indicate how text-mining strategies allied with features of semantic and network analysis can be used to unravel the basic elements of policy stories and to facilitate the presentation of data in such a way that readers can verify the strengths (and weaknesses) of any given analysis – with regard to claims concerning, say, the presence, absence or relative importance of key ideas and concepts. Readers can also ‘see’ how the different components of any one story might fit together, and to get a sense of what has been excluded from the narrative as well as what has been included, and thereby assess the reliability and validity of interpretations that have been placed upon the data.
Market Failure or Governmental Failure? A Study of China's Water Abstraction Policies
Authors: Li Wei , Beresford Melanie , Song Guojun
Published: January 2012

China's water abstraction policies are significant for illustrating the application of market-based instruments in a transitional and developing country and for shedding light on improving China's water management system. This article presents a new approach to analysing applications of market-based instruments for water resources in China. Expanding the analysis beyond a rational choice approach, it demonstrates the institutional dimension of policy implementation at the local level in China. Four peculiar features of China's water institutions influence local governments in dealing with water abstraction differently from how regulators might expect. This explains local governmental failures and the implementation of water abstraction policies in several ways, including the setting of charges at low levels, a lack of necessary monitoring and sanctions, few incentives to collect charges diligently, and failure to provide accessible information for the public.
The metabolic implications of long term cannabis use in patients with psychosis
Authors: Mushtaq Farrah , Mondelli Valeria , Pariante Carmine M.
Published: January 2012

AimsThe aim of this paper is to summarise the effects of cannabis use on appetite and energy balance, and to subsequently investigate the possible implications this may have in patients with psychosis, in whom a high prevalence of cannabis use has been reported.Methods– A narrative review based on the recent literature regarding cannabis use in the gen-eral population and patients with psychosis.Results– The short-term abilities of cannabis to increase appetite and body weight, through actions on the endogenous endocannabinoid system, have been well characterised throughout the literature. The long term effects of cannabis use are however unclear and only a minority of studies have been conducted in the general population with overall conflicting results. In terms of the effects of cannabis in patients with psychosis, there has only been one study to date that has investigated this and interestingly found cannabis use to be associated with increased body weight and blood glucose levels, thus providing evidence that cannabis use may be an important contributing factor to the reduced life expectancy, as is currently observed in this vulnerable patient group.Conclusions– It is clear from the literature that patients with psychosis are at a high risk of metabolic and cardiovascular disease in comparison to the general population. However the contribution of cannabis use to this risk is as of yet undetermined and further long term studies are need to confirm current findings and evaluate hypothesised mechanisms.

Declaration of Interest: None.
The Community Assessment Psychic Experience (CAPE): evaluation study of the Italian version
Authors: Daneluzzo Enrico , Tommaso Silvia Di , Tempesta Daniela , Cerroni Gianluigi , Stratta Paolo , Rossi Alessandro
Published: January 2012

Negli ultimi anni il modello categoriale della psicosi e della schizofrenia in particolare, è stato riconsiderato a favore di una visione dimensionale. Questa assume che I sintomi psicotici differiscono in modo quantitativo dalle normali esperienze psichiche distribuendosi lungo un continuum che va dalla popolazione clinica affetta da schizofrenia ad individui con disturbo di personalità, fino alla popolazione generale che può mostrare esperienze simil psicotiche (Hanssen et al., 2003; Johns & Phil, 2005). Tale continuità fenomenologica è suggerita da studi che mostrano che le dimensioni del fenotipo della psicosi subclinica sono molto simili a quelle identificate nei disturbi clinici (Van Os et al. 2000; Van Os & Tamminga, 2007; Rossler et al., 2007). Sono state infatti riportate dimensioni positive e negative sia in ambito clinico che subclinico, mentre più incerta appare la presenza della dimensione disorganizzazione (Vollema & Hoijtink, 2000; van Os et al., 2002). Vari studi hanno riportato che i fenotipi clinico e non clinico condividono fattori di rischio, meccanismi psicologici ed i pattern epidemiologici (Sharpley & Peters,1999; Johns & van Os, 2001; van Os et al., 2001), fornendo un'ulteriore prova che l'espressione clinica e subclinica delle psicosi fanno parte dello stesso continuum.
Glutamate receptors: the cause or cure in perinatal white matter injury?
Authors: Fields R. Douglas
Published: January 2012

Glutamate toxicity from hypoxia-ischaemia during the perinatal period causes white matter injury that can result in long-term motor and intellectual disability. Blocking ionotropic glutamate receptors (GluRs) has been shown to inhibit oligodendrocyte injury in vitro, but GluR antagonists have not yet proven helpful in clinical studies. The opposite approach of activating GluRs on developing oligodendrocytes shows promise in experimental studies on rodents as reported by Jartzie et al., in this issue. Group I metabotropic glutamate receptors (mGluRs) are expressed transiently on developing oligodendrocytes in humans during the perinatal period, and the blood–brain-barrier permeable agonist of group I mGluRs, 1-aminocyclopentane-trans-1,3-dicarboxylic acid (ACPD), reduces white matter damage significantly in a rat model of perinatal hypoxia-ischaemia. The results suggest drugs activating this class of GluRs could provide a new therapeutic approach for preventing cerebral palsy and other neurological consequences of diffuse white matter injury in premature infants.
On the role of slab pull in the Cenozoic motion of the Pacific plate
Authors: Faccenna Claudio , Becker Thorsten W. , Lallemand Serge , Steinberger Bernhard
Published: January 2012

We analyze the role of slab pull acting on the Pacific plate during its early Tertiary change in motion. Slab pull forces are estimated by integrating the negative buoyancy of a 700 km long slab along a revised subduction boundary model adopting the Müller et al. (2008) seafloor age reconstructions. Our results indicate that torques predicted from a simple slab pull model match the Pacific plate Euler vectors during the Tertiary fairly well. The change of the Pacific motion at ∼50–40 Ma appears to be driven by the onset of the Izu‐Bonin‐Mariana system and, soon afterwards, by the Tonga‐Kermadec subduction zones.
The effects of gentle topographic variation on dispersal kernels of inertial particles
Authors: Katul G. G. , Poggi D.
Published: January 2012

Seed dispersal kernels of wind‐dispersed species imprint the initial spatial template over which later demographic processes such as establishment or re‐colonization operate from. A major knowledge gap in seed dispersal modeling by wind is the role of complex topography in modifying the kernel shape when referenced to the flat‐world case. How complex topography modifies the dispersal kernels of inertial particles such as seeds is explored here via novel flume experiments. A train of gentle cosine hills and a canopy composed of densely arrayed rods with a roughness density resembling the leaf area density profile of hardwood species at maximum leaf area were used to represent a canopy‐hill system. Spherical inertial particles having a coefficient of variation in terminal velocity commensurate with values reported from field studies were employed as model seeds. It was demonstrated that the seed dispersal kernel maintained its canonical ‘Wald’ form as derived from simplified turbulent dispersion theories for flat terrain and vertically uniform flow field. Seeds released near the canopy top and from the top of the hill have a dispersal kernel mean distance that was about 35% times larger than its counterpart for releases from the bottom of the hill. Moreover, the probability of occurrence of long‐distance dispersal (LDD) events, defined here as seeds traversing a longitudinal distance exceeding 10 times the canopy height, were one order of magnitude larger for seeds released near the canopy top and from the hill top when compared to their counterpart released from the hill bottom.
Magnetic discrimination between Al‐substituted hematites synthesized by hydrothermal and thermal dehydration methods and its geological significance
Authors: Jiang Zhaoxia , Liu Qingsong , Barrón Vidal , Torrent José , Yu Yongjae
Published: January 2012

Hematite, a ubiquitous mineral in aerobic sediments and soils of temperate and warm areas, is weakly magnetic. However, it carries a stable natural remanent magnetization, and thus can reflect paleoenvironment changes. To quantify the influence of Al content in hematite on its magnetic properties, two series of hematite particles were prepared by hydrothermal transformation of ferrihydrite in aqueous suspension (HFh* series) and by thermal dehydration of goethite (HG* series). Crystal morphological and mineral magnetic properties of these two types of hematites differ distinctively. More specifically, the HFh* series samples display oblate (plate‐like) morphologies, while the HG* series samples are prolate (highly acicular). HFh* series samples display higher saturation magnetization but lower magnetic coercivity than that of the HG* series. It is tenable that a better lattice ordering of Al substitution occurs during the process of dehydration of goethite than after transformation from ferrihydrite, resulting in weaker saturation magnetization for HG* series samples. The origin of single domain (SD) hematite in nature can be diagnosed by the correlation of unblocking temperature and magnetic coercivity: a positive correlation indicates the presence of pure (Al‐free) SD hematite, while a negative correlation indicates a chemical origin of SD Al‐substituted hematite. These results bear new information on decoding the complex magnetic properties of SD Al‐hematite in nature environments, and thus deepen our understanding of the mechanism of variations in both paleomagnetic and paleoenvironmental signals carried by Al‐hematite.
The optical volume scattering function in a surf zone inverted to derive sediment and bubble particle subpopulations
Authors: Twardowski Michael , Zhang Xiaodong , Vagle Svein , Sullivan James , Freeman Scott , Czerski Helen , You Yu , Bi Lei , Kattawar George
Published: January 2012

The effects of particle fields including bubbles on the optical volume scattering function (VSF) were investigated in the surf zone off Scripps Pier as part of an ongoing effort to better understand the underlying dynamics in the VSF in the subsurface ocean. VSFs were measured at 20 Hz at angles spanning 10°–170° in 10° increments with a device called the Multiangle Scattering Optical Tool (MASCOT). Modification of the phase function was observed in passing suspended sediment plumes, wave‐injected bubble plumes, and combinations of these particle populations relative to the background. Phase function enhancement in the 60°–80° range was observed in association with bubble plumes, consistent with theoretical predictions. VSFs were inverted to infer size distributions and composition using a least squares minimization fitting procedure applied to a library of phase functions, each representing a lognormally distributed subpopulation with refractive index and coating, where applicable. Phase functions representative of nonspherical mineral particle subpopulations were computed using discrete dipole approximation (DDA) and improved geometric optics method (IGOM) techniques for randomly oriented, asymmetric hexahedra. Phase functions for coated bubbles were computed with the Lorenz‐Mie theory. Inversion results exhibited stable solutions that qualitatively agreed with concurrent acoustical measurements of bubbles, aggregate particle size distribution expectations, and anecdotal videography evidence from the field. Although a comparable inversion with a library that assumed spherical shaped particles alone provided less stable results with some incorrectly assigned subpopulations, several dominant subpopulation trends were consistent with the results obtained using nonspherical representations of mineral particles.
Phosphorus export across an urban to rural gradient in the Chesapeake Bay watershed
Authors: Duan Shuiwang , Kaushal Sujay S. , Groffman Peter M. , Band Lawrence E. , Belt Kenneth T.
Published: January 2012

Watershed export of phosphorus (P) from anthropogenic sources has contributed to eutrophication in freshwater and coastal ecosystems. We explore impacts of watershed urbanization on the magnitude and export flow distribution of P along an urban‐rural gradient in eight watersheds monitored as part of the Baltimore Ecosystem Study Long‐Term Ecological Research site. Exports of soluble reactive phosphorus (SRP) and total P (TP) were lowest in small watersheds with forest and low‐density residential land use (2.8–3.1 kg−1 km−2 yr−1). In contrast, SRP and TP exports increased with watershed impervious surface coverage and reached highest values in a small urban watershed (24.5–83.7 kg−1 km−2 yr−1). Along the Gwynns Falls, a larger watershed with mixed land use, the greatest proportion of SRP (68%) and TP (75%) was contributed from the lower watershed, where urban areas were the dominant land use. Load duration curve analysis showed that increasing urbanization in watersheds was associated with shifts in P export to high‐flow conditions (>2 mm d−1). SRP concentrations during low‐flow conditions at urban headwater sites were highest during summer and lowest during winter. This seasonal pattern was consistent with sediment incubation experiments showing that SRP release from sediments was temperature dependent. Our results suggest that shifts in streamflow and alterations in water temperatures owing to urbanization and climate can influence stream water P concentrations and P export from urban watersheds.
Solute transport in divergent radial flow with multistep pumping
Authors: Chen Yiming , Lu Chunhui , Luo Jian
Published: January 2012

An efficient approach is developed to analytically evaluate solute transport in a horizontal, divergent radial flow field with a multistep injection flow rate and an arbitrary input concentration history. By assuming a piecewise steady state flow and transforming the time domain to the cumulative injected flow domain, the concentration distribution is found to be completely determined by the total volume of injected flow and independent of specific flow rates. Thus, on the cumulative flow domain, the transport problem with a temporally varying velocity field can be transformed into a steady state flow problem. Linear convolution can then be applied on the cumulative injected flow domain to evaluate the solution for an arbitrarily time‐dependent input concentration. Solutions on the regular time domain can be conveniently obtained by mapping the solution on the cumulative injected flow domain to the time domain. Furthermore, we theoretically examine the conditions for the assumption of piecewise steady state flow to be valid. On the basis of the critical time scale of the “pseudosteady state condition,” defined as when velocity changes accomplish 99% of their steady state differences, and the relative error in the mean travel time of plume front, we obtain conditions for neglecting the transitional period between two pumping steps. Such conditions include the following: (1) the duration of a pumping step, tp, must be longer than the critical time scale, tc, i.e., tp ≥ tc = 25r2S/T, where r is the radial distance, S is the storage coefficient, and T is the transmissivity, or similarly, a maximum problem domain needs to be defined for a given pumping strategy. (2) the maximum well pumping rate, qmax, should satisfy qmax ≤ πθT/25S, where θ is the effective porosity. When both conditions are satisfied, transitional periods may be neglected.
Communication-Based Assessment of Developmental Age for Young Children With Developmental Disabilities
Authors: DeVeney Shari L. , Hoffman Lesa , Cress Cynthia J.
Published: January 2012

Purpose

In this study, the authors compared a multiple-domain strategy for assessing developmental age of young children with developmental disabilities who were at risk for long-term reliance on augmentative and alternative communication (AAC) with a communication-based strategy composed of receptive language and communication indices that may be less affected by physically challenging tasks than traditional developmental age scores.

Method

Participants were 42 children (age 9–27 months) with developmental disabilities and who were at risk for long-term reliance on AAC. Children were assessed longitudinally in their homes at 3 occasions over 18 months using multiple-domain and communication-based measures. Confirmatory factor analysis examined dimensionality across the measures, and age-equivalence scores under each strategy were compared, where possible.

Results

The communication-based latent factor of developmental age demonstrated good reliability and was almost perfectly correlated with the multiple-domain latent factor. However, the mean age-equivalence score of the communication-based assessment significantly exceeded that of the multiple-domain assessment by 5.3 months across ages.

Conclusions

Clinicians working with young children with developmental disabilities should consider a communication-based approach as an alternative developmental age assessment strategy for characterizing children's capabilities, identifying challenges, and developing interventions. A communication-based developmental age estimation is sufficiently reliable and may result in more valid inferences about developmental age for children whose developmental or cognitive age scores may otherwise be limited by their physical capabilities.
Predicting Later Language Outcomes From the Language Use Inventory
Authors: Pesco Diane , O’Neill Daniela K.
Published: January 2012

Purpose

To examine the predictive validity of the Language Use Inventory (LUI), a parent report of language use by children 18–47 months old (O’Neill, 2009).

Method

348 children whose parents had completed the LUI were reassessed at 5–6 years old with standardized, norm-referenced language measures and parent report of developmental history. The relationship between scores on the LUI and later measures was examined through correlation, binary classification, and receiver operating characteristic curve analysis.

Results

For children aged 24–47 months at the time of LUI completion, LUI scores correlated significantly with language measure scores. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were also calculated for 4 cutoff scores on the LUI, including −1.64SD,a score that maximized sensitivity to 81% and specificity to 93%. For children aged 18–23 months at the time of LUI completion, specificity and NPV were high, but sensitivity and PPV were lower than desirable.

Conclusions

The results provide initial support for the LUI’s predictive validity, particularly for children 24–47 months, and suggest the LUI can serve as an indicator of later language outcomes in referred populations. The results compare favorably to findings for other early child-language measures.
Children's Verbal Working Memory: Role of Processing Complexity in Predicting Spoken Sentence Comprehension
Authors: Magimairaj Beula M. , Montgomery James W.
Published: January 2012

Purpose

This study investigated the role of processing complexity of verbal working memory tasks in predicting spoken sentence comprehension in typically developing children. Of interest was whether simple and more complex working memory tasks have similar or different power in predicting sentence comprehension.

Method

Sixty-five children (6- to 12-year-olds) completed a verbal working memory (listening) span task that varied in syntactic processing difficulty (simple sentences representing a “simple working memory task,” complex sentences representing a “complex working memory task”) and a standardized sentence comprehension test.

Results

Word recall on the simple and complex working memory tasks correlated with each other. Both memory tasks also correlated with children's sentence comprehension. Regression analyses showed that the simple working memory task remained a significant predictor of comprehension even after accounting for variance associated with age and performance on the complex working memory task.

Conclusions

Results were interpreted to suggest that relative to more complex verbal working memory tasks, simple tasks are more robust predictors of children's sentence comprehension because they represent a basic yet robust index of working memory that sufficiently captures controlled attentional focus.
Controlled p-type to n-type conductivity transformation in NiO thin films by ultraviolet-laser irradiation
Authors: Gupta Pranav , Dutta Titas , Mal Siddhartha , Narayan Jagdish
Published: January 2012

We report the systematic changes in structural, electrical, and optical properties of NiO thin films on c-sapphire introduced by nanosecond ultraviolet excimer laser pulses. Epitaxial nature of as deposited NiO was determined by x-ray diffraction phi scans and transmission electron microscopy (TEM) and it was established that NiO film growth takes place with twin domains on sapphire where two types of domains have 60° in-plane rotation with respect to each other about the [111] growth direction. We determined that at pulsed laser energy density of 0.275 J/cm2, NiO films exhibited conversion from p-type semiconducting to n-type conductive behavior with three orders of magnitude decrease in resistivity, while maintaining its cubic crystal structure and good epitaxial relationship. Our TEM and electron-energy-loss spectroscopy studies conclusively ruled out the presence of any Ni clustering or precipitation due to the laser treatment. The laser-induced n-type carrier transport and conductivity enhancement were shown to be reversible through subsequent thermal annealing in oxygen. This change in conductivity behavior was correlated with the nonequilibrium concentration of laser induced Ni0-like defect states.
Spin separation in a quantum dot ring driven by a temperature bias
Authors: Gong Wei-Jiang , Fan Shuang , Kariuki Francis N. , Wei Guo-Zhu , Du An
Published: January 2012

By introducing local Rashba spin-orbit interaction in a three-terminal quantum dot ring, we calculate the currents induced by thermoelectric effect. It shows that, when a temperature bias is applied between the source and drains, there emerge apparent spin currents in the two drains. We find, via adjusting the structure parameters, that an electron from the source will choose its drain according to its spin index. Due to the advances in nanodevice fabrication, this structure can be constructed, and then we believe that it can be a candidate of the spin-manipulating device.
Instability in internal solitary waves with trapped cores
Authors: Carr M. , King S. E. , Dritschel D. G.
Published: January 2012

A numerical method that employs a combination of contour advection and pseudo-spectral techniques is used to investigate instability in internal solitary waves with trapped cores. A three-layer configuration for the background stratification in which the top two layers are linearly stratified and the lower layer is homogeneous is considered throughout. The strength of the stratification in the very top layer is chosen to be sufficient so that waves of depression with trapped cores can be generated. The flow is assumed to satisfy the Dubriel-Jacotin-Long equation both inside and outside of the core region. The Brunt-Vaisala frequency is modelled such that it varies from a constant value outside of the core to zero inside the core over a sharp but continuous transition length. This results in a stagnant core in which the vorticity is zero and the density is homogeneous and approximately equal to that at the core boundary. The time dependent simulations show that instability occurs on the boundary of the core. The instability takes the form of Kelvin-Helmholtz billows. If the instability in the vorticity field is energetic enough, disturbance in the buoyancy field is also seen and fluid exchange takes place across the core boundary. Occurrence of the Kelvin-Helmholtz billows is attributed to the sharp change in the vorticity field at the boundary between the core and the pycnocline. The numerical scheme is not limited by small Richardson number unlike the other alternatives currently available in the literature which appear to be.
Clusters dissolution of Yb3+ in codoped SiO2-Al2O3-P2O5 glass fiber and its relevance to photodarkening
Authors: Deschamps T. , Ollier N. , Vezin H. , Gonnet C.
Published: January 2012

Using a combination of pulse electron paramagnetic resonance and photoluminescence spectroscopy, we demonstrate the major role of phosphorous rather than aluminium in the rare-earth dissolution process, an essential advance in telecommunication and solid laser fields. Our results also provide new insight into the micro-structural origin of the photodarkening process occurring in Yb doped fiber.
Efficiency enhancement of InGaN multi-quantum-well solar cells via light-harvesting SiO2 nano-honeycombs
Authors: Fu P. H. , Lin G. J. , Ho C. H. , Lin C. A. , Kang C. F. , Lai Y. L. , Lai K. Y. , He J. H.
Published: January 2012

Periodic sub-wavelength SiO2 nano-honeycombs are fabricated on GaN-based multiple quantum well solar cells by self-assembly polystyrene nanosphere lithography and reactive ion etching. The nano-honeycombs are found to be effective in suppressing the undesired surface reflections over a wide range of wavelengths. Under the illumination of air mass 1.5G solar simulator, conversion efficiency of the solar cell is enhanced by 24.4%. Simulations based on finite-difference time-domain method indicate that the improved performances result from the enhanced optical absorption in the active region due to the reflection suppression and enhanced forward scattering.
High data-rate atom interferometer for measuring acceleration
Authors: McGuinness Hayden J. , Rakholia Akash V. , Biedermann Grant W.
Published: January 2012

We demonstrate a high data-rate light-pulse atom interferometer for measuring acceleration. The device is optimized to operate at rates between 50 Hz to 330 Hz with sensitivities of 0.57μg/Hz to 36.7μg/Hz, respectively. Our method offers a dramatic increase in data rate and demonstrates a path to applications in highly dynamic environments. The performance of the device can largely be attributed to the high recapture efficiency of atoms from one interferometer measurement cycle to another.