bluuebunny/crossref_metadata_2025 huggingface dataset:
The Logic of Provability
Authors: Boolos George S.
Published: February 2010

This book, written by one of the most distinguished of contemporary philosophers of mathematics, is a fully rewritten and updated successor to the author's earlier The Unprovability of Consistency (1979). Its subject is the relation between provability and modal logic, a branch of logic invented by Aristotle but much disparaged by philosophers and virtually ignored by mathematicians. Here it receives its first scientific application since its invention. Modal logic is concerned with the notions of necessity and possibility. What George Boolos does is to show how the concepts, techniques, and methods of modal logic shed brilliant light on the most important logical discovery of the twentieth century: the incompleteness theorems of Kurt Godel and the 'self-referential' sentences constructed in their proof. The book explores the effects of reinterpreting the notions of necessity and possibility to mean provability and consistency.
Introduction to Geostatistics
Authors: Kitanidis P. K.
Published: February 2010

Engineers and applied geophysicists routinely encounter interpolation and estimation problems when analysing data from field observations. Introduction to Geostatistics presents practical techniques for the estimation of spatial functions from sparse data. The author's unique approach is a synthesis of classic and geostatistical methods with a focus on the most practical linear minimum-variance estimation methods, and includes suggestions on how to test and extend the applicability of such methods.
The author includes many useful methods (often not covered in other geostatistics books) such as estimating variogram parameters, evaluating the need for a variable mean, parameter estimation and model testing in complex cases (e.g. anisotropy, variable mean, and multiple variables), and using information from deterministic mathematical models.
Well illustrated with exercises and worked examples taken from hydrogeology, Introduction to Geostatistics assumes no background in statistics and is suitable for graduate-level courses in earth sciences, hydrology, and environmental engineering, and also for self-study.
Scandal on Stage
Authors: Ziolkowski Theodore
Published: February 2010

New plays and operas have often tried to upset the status quo or disturb the assumptions of theatre audiences. Yet, as this study explores, the reactions of the audience or of the authorities are often more extreme than the creators had envisaged, to include outrage, riots, protests or censorship. Scandal on Stage looks at ten famous theater scandals of the past two centuries in Germany and France as symptoms of contemporary social, political, ethical, and aesthetic upheavals. The writers and composers concerned, including Schiller, Stravinsky, Strauss, Brecht and Weil, portrayed new artistic and ideological ideas that came into conflict with the expectations of their audiences. In a comparative perspective, Theodore Ziolkowski shows how theatrical scandals reflect or challenge cultural and ethical assumptions and asks whether theatre can still be, as Schiller wrote, a moral institution: one that successfully makes its audience think differently about social, political and ethical questions.
The Political Conditionality of Mass Media Influence: When Do Parties Follow Mass Media Attention?
Authors: Green-Pedersen Christoffer , Stubager Rune
Published: February 2010

Claims regarding the power of the mass media in contemporary politics are much more frequent than research actually analysing the influence of mass media on politics. Building upon the notion of issue ownership, this article argues that the capacity of the mass media to influence the respective agendas of political parties is conditioned upon the interests of the political parties. Media attention to an issue generates attention from political parties when the issue is one that political parties have an interest in politicizing in the first place. The argument of the article is supported in a time-series study of mass media influence on the opposition parties’ agenda in Denmark over a twenty-year period.
Simulations of shear instabilities in interfacial gravity waves
Authors: BARAD MICHAEL F. , FRINGER OLIVER B.
Published: February 2010

An adaptive numerical method is employed to simulate shear instabilities in open-ocean internal solitary-like gravity waves. The method is second-order accurate, employs block-structured adaptive mesh refinement, solves the incompressible Navier–Stokes equations and allows for the simulation of all of the length scales of interest by dynamically tracking important regions with recursively-nested finer grids. Two-dimensional simulations are performed over a range of parameters, which allows us to assess the conditions under which the shear instabilities in the waves occur, including a method to evaluate the critical Richardson number for instability based on the bulk wave parameters. The results show that although the minimum Richardson number is well below the canonical value of 1/4 in all simulations, this value is not a sufficient condition for instability, but instead a much lower Richardson number of 0.1 is required. When the Richardson number falls below 0.1, shear instabilities develop and grow into two-dimensional billows of the Kelvin–Helmholtz type. A linear stability analysis with the Taylor–Goldstein equation indicates that an alternate criterion for instability is given by σiTw > 5, where σi is the growth rate of the instability averaged over Tw, the period in which parcels of fluid are subjected to a Richardson number of less than 1/4. A third criterion for instability requires that Lw/L > 0.86, where Lw is half the length of the region in which the Richardson number falls below 1/4 and L is the solitary wave half-width. An eigendecomposition of the rate-of-strain tensor is performed to show that the pycnocline thickness increases within the wave because of pycnocline-normal strain and not because of diffusion, which has important ramifications for stability. A three-dimensional simulation indicates that the primary instability is two-dimensional and that secondary, three-dimensional instabilities occur thereafter and lead to strong dissipation and mixing.
Three-dimensional vortex organization in a high-Reynolds-number supersonic turbulent boundary layer
Authors: ELSINGA G. E. , ADRIAN R. J. , VAN OUDHEUSDEN B. W. , SCARANO F.
Published: February 2010

Tomographic particle image velocimetry was used to quantitatively visualize the three-dimensional coherent structures in a supersonic (Mach 2) turbulent boundary layer in the region between y/δ = 0.15 and 0.89. The Reynolds number based on momentum thickness Reθ = 34000. The instantaneous velocity fields give evidence of hairpin vortices aligned in the streamwise direction forming very long zones of low-speed fluid, consistent with Tomkins & Adrian (J. Fluid Mech., vol. 490, 2003, p. 37). The observed hairpin structure is also a statistically relevant structure as is shown by the conditional average flow field associated to spanwise swirling motion. Spatial low-pass filtering of the velocity field reveals streamwise vortices and signatures of large-scale hairpins (height > 0.5δ), which are weaker than the smaller scale hairpins in the unfiltered velocity field. The large-scale hairpin structures in the instantaneous velocity fields are observed to be aligned in the streamwise direction and spanwise organized along diagonal lines. Additionally the autocorrelation function of the wall-normal swirling motion representing the large-scale hairpin structure returns positive correlation peaks in the streamwise direction (at 1.5δ distance from the DC peak) and along the 45° diagonals, which also suggest a periodic arrangement in those directions. This is evidence for the existence of a spanwise–streamwise organization of the coherent structures in a fully turbulent boundary layer.
The hydrodynamics of water-walking arthropods
Authors: HU DAVID L. , BUSH JOHN W. M.
Published: February 2010

We present the results of a combined experimental and theoretical investigation of the dynamics of water-walking insects and spiders. Using high-speed videography, we describe their numerous gaits, some analogous to those of their terrestrial counterparts, others specialized for life at the interface. The critical role of the rough surface of these water walkers in both floatation and propulsion is demonstrated. Their waxy, hairy surface ensures that their legs remain in a water-repellent state, that the bulk of their leg is not wetted, but rather contact with the water arises exclusively through individual hairs. Maintaining this water-repellent state requires that the speed of their driving legs does not exceed a critical wetting speed. Flow visualization reveals that the wakes of most water walkers are characterized by a series of coherent subsurface vortices shed by the driving stroke. A theoretical framework is developed in order to describe the propulsion in terms of the transfer of forces and momentum between the creature and its environment. The application of the conservation of momentum to biolocomotion at the interface confirms that the propulsion of water walkers may be rationalized in terms of the subsurface flows generated by their driving stroke. The two principal modes of propulsion available to small water walkers are elucidated. At driving leg speeds in excess of the capillary wave speed, macroscopic curvature forces are generated by deforming the meniscus, and the surface behaves effectively as a trampoline. For slower speeds, the driving legs need not substantially deform the surface but may instead simply brush it: the resulting contact or viscous forces acting on the leg hairs crossing the interface serve to propel the creature forward.
Concentration flux measurements in a polymer drag-reduced turbulent boundary layer
Authors: SOMANDEPALLI V. S. R. , HOU Y. X. , MUNGAL M. G.
Published: February 2010

The drag-reducing action of dilute solutions of long-chain polymers in a flat-plate turbulent boundary layer is studied using particle imaging velocimetry (PIV) and planar laser induced fluorescence (PLIF). The results are used to characterize and quantify the spatial distribution of the injected polymer solution and the downstream development of the DR along the flat plate. The two techniques were used simultaneously to document and study the spread of the injected polymer solution and the resulting changes in the structure and statistics of the turbulence in the boundary layer. The PLIF images provide a qualitative and quantitative measure of the dispersion of the injected polymer solution. The mean and root mean square (r.m.s.) concentration profiles obtained using PLIF showed that the polymer greatly suppressed the turbulent dispersion in the near-wall region. The quantitative concentration measurements across the boundary layer, combined with simultaneous velocity measurements, are used to obtain concentration flux measurements in the boundary layer and are used to study the effect of the turbulence on the dispersion of the injected polymer. The variation of the fluxes with concentration of the injected polymer solutions and with increasing downstream distance is also studied and documented. The action of the polymer is to reduce the streamwise fluxes in the boundary layer, the suppression increasing with concentration. Further, the fluxes are also used to estimate the turbulent Schmidt number (ScT) for the drag-reduced flow. For the polymer injection experiments, theScTare all greater than unity with the highest magnitude measured to be around 6, with the magnitude increasing with increasing concentration of the injected solutions. However, for each experiment, the estimatedScTdecreases along the length of the flat plate reflecting the loss of polymer effectiveness.
High-mode stationary waves in stratified flow over large obstacles
Authors: KLYMAK JODY M. , LEGG SONYA M. , PINKEL ROBERT
Published: February 2010

Simulations of steady two-dimensional stratified flow over an isolated obstacle are presented where the obstacle is tall enough so that the topographic Froude number, Nhm/Uo ≫ 1. N is the buoyancy frequency, hm the height of the topography from the channel floor and Uo the flow speed infinitely far from the obstacle. As for moderate Nhm/Uo (~1), a columnar response propagates far up- and downstream, and an arrested lee wave forms at the topography. Upstream, most of the water beneath the crest is blocked, while the moving layer above the crest has a mean velocity Um = UoH/(H−hm). The vertical wavelength implied by this velocity scale, λo = 2πUm/N, predicts dominant vertical scales in the flow. Upstream of the crest there is an accelerated region of fluid approximately λo thick, above which there is a weakly oscillatory flow. Downstream the accelerated region is thicker and has less intense velocities. Similarly, the upstream lift of isopycnals is greatest in the first wavelength near the crest, and weaker above and below. Form drag on the obstacle is dominated by the blocked response, and not on the details of the lee wave, unlike flows with moderate Nhm/Uo.

Directly downstream, the lee wave that forms has a vertical wavelength given by λo, except for the deepest lobe which tends to be thicker. This wavelength is small relative to the fluid depth and topographic height, and has a horizontal phase speed cpx = −Um, corresponding to an arrested lee wave. When considering the spin-up to steady state, the speed of vertical propagation scales with the vertical component of group velocity cgz = αUm, where α is the aspect ratio of the topography. This implies a time scale = tNα/2π for the growth of the lee waves, and that steady state is attained more rapidly with steep topography than shallow, in contrast with linear theory, which does not depend on the aspect ratio.
Impact of severity and type of depression on quality of life in cases identified in the community
Authors: Nuevo R. , Leighton C. , Dunn G. , Dowrick C. , Lehtinen V. , Dalgard O. S. , Casey P. , Vázquez-Barquero J. L. , Ayuso-Mateos J. L.
Published: February 2010

Background

The impact of different levels of depression severity on quality of life (QoL) is not well studied, particularly regarding ICD-10 criteria. The ICD classification of depressive episodes in three levels of severity is also controversial and the less severe category, mild, has been considered as unnecessary and not clearly distinguishable from non-clinical states. The present work aimed to test the relationship between depression severity according to ICD-10 criteria and several dimensions of functioning as assessed by Medical Outcome Study (MOS) 36-item Short Form general health survey (SF-36) at the population level.

Method

A sample of 551 participants from the second phase of the Outcome of Depression International Network (ODIN) study (228 controls without depression and 313 persons fulfilling ICD criteria for depressive episode) was selected for a further assessment of several variables, including QoL related to physical and mental health as measured with the SF-36.

Results

Statistically significant differences between controls and the depression group were found in both physical and mental markers of health, regardless of the level of depression severity; however, there were very few differences in QoL between levels of depression as defined by ICD-10. Regardless of the presence of depression, disability, widowed status, being a woman and older age were associated with worse QoL in a structural equation analysis with covariates. Likewise, there were no differences according to the type of depression (single-episode versus recurrent).

Conclusions

These results cast doubt on the adequacy of the current ICD classification of depression in three levels of severity.
The defensibility of Zoroastrian dualism
Authors: KRONEN JOHN D. , MENSSEN SANDRA
Published: February 2010

Contemporary philosophical discussion of religion neglects dualistic religions: although Manichaeism from time to time is accorded mention, Zoroastrianism, a more plausible form of religious dualism, is almost entirely ignored. We seek to change this state of affairs. To this end we (1) present the basic tenets of Zoroastrian dualism, (2) argue that objections to the Zoroastrian conception of God are less strong than typically imagined, (3) argue that objections to the Zoroastrian conception of the devil (and evil) are less strong than typically imagined, and (4) offer some brief concluding thoughts.
The evil-god challenge
Authors: LAW STEPHEN
Published: February 2010

This paper develops a challenge to theism. The challenge is to explain why the hypothesis that there exists an omnipotent, omniscient and all-good god should be considered significantly more reasonable than the hypothesis that there exists an omnipotent, omniscient and all-evil god. Theists typically dismiss the evil-god hypothesis out of hand because of theproblem of good– there is surely too much good in the world for it to be the creation of such a being. But then why doesn't the problem of evil provide equally good grounds for dismissing belief in a good god? I develop thisevil-god challengein detail, anticipate several replies, and correct errors made in earlier discussions of the problem of good.
A proper de jure objection to the epistemic rationality of religious belief
Authors: LONG TODD R.
Published: February 2010

I answer Alvin Plantinga's challenge to provide a ‘proper’ de jure objection to religious belief. What I call the ‘sophisticates’ evidential objection' (SEO) concludes that sophisticated Christians lack epistemic justification for believing central Christian propositions. The SEO utilizes a theory of epistemic justification in the spirit of the evidentialism of Richard Feldman and Earl Conee. I defend philosophical interest in the SEO (and its underlying evidentialism) against objections from Reformed epistemology, by addressing Plantinga's criteria for a proper de jure objection, his anti-evidentialist arguments, and the relevance of ‘impulsional evidence’. I argue that no result from Plantinga-style Reformed epistemology precludes the reasons I offer in favour of giving the SEO its due philosophical attention.
Staphylococcus aureus carriage in care homes: identification of risk factors, including the role of dementia
Authors: LASSETER G. , CHARLETT A. , LEWIS D. , DONALD I. , HOWELL-JONES R. , McNULTY C. A. M.
Published: February 2010

The aim of this study was to investigate the prevalence and associated risk factors of methicillin-susceptible and methicillin-resistant Staphylocccus aureus (MSSA and MRSA) carriage in care homes, with particular focus on dementia. A point-prevalence survey of 748 residents in 51 care homes in Gloucestershire and Greater Bristol was undertaken. Dementia was assessed by the clock test or abbreviated mini-mental test. Nasal swabs were cultured for S. aureus on selective agar media. Multivariable analysis indicated that dementia was not a significant risk factor for MSSA (16·2%) or MRSA (7·8%); and that residents able to move around the home unassisted were at a lower risk of MRSA (P=0·04). MSSA carriage increased with increasing age (P=0·03) but MRSA carriage decreased with increasing age (P=0·05). Hospitalization in the last 6 months increased the risk of MSSA (P=0·04) and MRSA (P=0·10). We concluded that cross-infection through staff caring for more dependent residents may spread MRSA within care homes and from the recently hospitalized. Control of MSSA and MRSA in care homes requires focused infection control interventions.
Humanitarians and their moral stance in war: the underlying values
Authors: Wortel Eva
Published: February 2010

In this article, the moral values underlying humanitarian principles are analysed. What were these original moral values? Have they changed? To what extent are they in danger today? Has humanity itself become an instrumental value? To answer these questions, the author examines the humanitarian discourse: firstly, how these values have been described by humanitarians themselves, and secondly, how they are used by humanitarians in specific contexts.
Between Amazons and Sabines: a historical approach to women and war
Authors: Herrmann Irène , Palmieri Daniel
Published: February 2010

Today, war is still perceived as being the prerogative of men only. Women are generally excluded from the debate on belligerence, except as passive victims of the brutality inflicted on them by their masculine contemporaries. Yet history shows that through the ages, women have also played a role in armed hostilities, and have sometimes even been the main protagonists. In the present article, the long history and the multiple facets of women's involvement in war are recounted from two angles: women at war (participating in war) and women in war (affected by war). The merit of a gender-based division of roles in war is then examined with reference to the ancestral practice of armed violence.
Women's participation in the Rwandan genocide: mothers or monsters?
Authors: Hogg Nicole
Published: February 2010

The participation of women in the 1994 Rwandan genocide should be considered in the context of gender relations in pre-genocide Rwandan society. Many ‘ordinary’ women were involved in the genocide but, overall, committed significantly fewer acts of overt violence than men. Owing to the indirect nature of women's crimes, combined with male ‘chivalry’, women may be under-represented among those pursued for genocide-related crimes, despite the broad conception of complicity in Rwanda's Gacaca Law. Women in leadership positions played a particularly important role in the genocide, and gendered imagery, including of the ‘evil woman’ or ‘monster’, is often at play in their encounters with the law.
Normdaten zur Ergänzung deutscher Wortanfänge
Authors: Bergmann Heiko C. , Müller Barbara C. N. , Danek Adrian
Published: February 2010

In der vorliegenden Arbeit werden Normdaten für eine Wortanfangsergänzungsaufgabe vorgestellt, die zu einem Großteil online erhoben wurden. Die Teilnehmer erhielten insgesamt 75 aus drei Buchstaben bestehende Wortanfänge. In der ersten von zwei Studien (501 Probanden, 16 bis 94 Jahre) mussten diese Wortanfänge zu einem deutschen Nomen, das aus insgesamt fünf, sechs oder sieben Buchstaben bestehen sollte, ergänzt werden. In der zweiten Studie (624 Probanden, 15 bis 70 Jahre) wurde die Limitierung der Buchstabenzahl aufgehoben: Die zu ergänzenden Nomina durften vier oder mehr Buchstaben haben. Für beide Studien werden die Ergebnisse der Gesamtstichprobe sowie diverser Subgruppen (stratifiziert nach Alter und Bildung) in Tabellenform präsentiert.
Impact of fracture development on the effective permeability of porous rocks as determined by 2‐D discrete fracture growth modeling
Authors: Paluszny A. , Matthai S. K.
Published: February 2010

Fracture networks exert a strong influence on fluid flow in the subsurface. We present a 2‐D linear elastic finite element model that generates fracture patterns in incremental iterative steps. A subcritical failure criterion is applied to simulate quasi‐static multiple crack propagation. We study their impact on fluid flow as a function of fracture density. Fractures are represented by closed polygons. Geomechanical apertures are a by‐product of growth and depend on the current stress state. Fracture arrest, closure, and coalescence are handled by a geometric kernel. Traction and cohesion along fracture walls are not taken into account. All patterns are generated assuming plane strain and applying displacement tensile boundary conditions. We assume randomly distributed flaw positions with a uniform probability distribution and Gaussian‐distributed flaw lengths. A piecewise fracture permeability is derived from the parallel plate law. We measure the effective permeability, keff, and fracture‐matrix flux ratio, qf/qm across the percolation threshold. Before the percolation threshold we observe an increase in keff of up to two orders of magnitude. Models with fixed apertures overpredict keff by up to six orders of magnitude, as they disregard variations in the aperture distribution due to fracture interaction. After percolation our model predicts steady linear increase in effective permeability. The qf/qm ratio better captures the initial increase in hydraulic conductivity of the system as opposed to the keff measurements. Results corroborate that fracture percolation and stress‐dependent aperture distribution due to mechanical interactions control the evolution of the keff of the system. Results depend on the number of initial flaws used for fracture set growth.
Wintertime mixed layer measurements at Maud Rise, Weddell Sea
Authors: Sirevaag Anders , McPhee Miles G. , Morison James H. , Shaw William J. , Stanton Timothy P.
Published: February 2010

Sea ice plays a crucial role in the exchange of heat between the ocean and the atmosphere, and areas of intense air‐sea‐ice interaction are important sites for water mass modification. The Weddell Sea is one of these sites where a relatively thin first‐year ice cover is constantly being changed by mixing of heat from below and stress exerted from the rapidly changing and intense winds. This study presents mixed layer turbulence measurements obtained during two wintertime drift stations in August 2005 in the eastern Weddell Sea, close to the Maud Rise seamount. Turbulence in the boundary layer is found to be controlled by the drifting ice. Directly measured heat fluxes compare well with previous studies and are well estimated from the mixed layer temperatures and mixing. Heat fluxes are also found to roughly balance the conductive heat flux in the ice; hence, little freezing/melting was observed. The under‐ice topography is estimated to be hydraulically very smooth; comparison with a steady 1‐D model shows that these estimates are made too close to the ice‐ocean interface to be representative for the entire ice floe. The main source and sink of turbulent kinetic energy are shear production and dissipation. Observations indicate that the dynamics of the under‐ice boundary layer are influenced by a horizontal variability in mixed layer density and an increasing amount of open leads in the area.
A preliminary assessment of the symmetry of source composition and melting dynamics across the Azores plume
Authors: Beier Christoph , Turner Simon , Plank Terry , White William
Published: February 2010

In order to undertake a preliminary assessment of the extent of symmetry in source composition and melting dynamics in the Azores plume we present new ICP‐MS trace element data along with Sr, Nd, Pb, and U‐Th‐Ra isotope data for samples from the islands Flores and Corvo west of the Mid‐Atlantic Ridge. We also present data from a picrite from Faial and new ICP‐MS trace element data for 28 basaltic lavas from the eastern Azores Plateau to augment data published previously from these samples. Rare earth element data for primitive lavas (MgO ≥ 5% and Mg # ≥ 60) have La/YbN ∼ 10 and variable Ce and/or Eu anomalies. Multi‐incompatible trace element patterns normalized to primitive mantle are convex upward with small negative Th and K ± Pb anomalies. While lavas to the east are characterized by low Nb/Zr and generally lower La/Yb ratios (with the notable exception of eastern São Miguel), lavas from the western islands have slightly higher Nb/Zr and La/Yb inferred to reflect smaller degrees of partial melting. The Sr‐Nd‐Pb isotope systematics imply that Corvo and Flores sample components which range from an isotopic source commonly found in the Azores (e.g., at the eastern island of Graciosa) to a more depleted, MORB‐like mantle sampled at the Mid‐Atlantic Ridge. However, in common with uncontaminated samples from São Miguel, the Corvo and Flores samples appear to have slightly lower 230Th excesses and higher La/Yb, Tb/Yb than the other Azores islands or the Mid‐Atlantic Ridge samples. The trace element and isotope data indicate a relatively symmetric pattern with distance across the MAR, while U‐Th disequilibria, and thus inferred melting dynamics, appear less symmetric. Nevertheless, the data suggest that heterogeneities in source composition do not have a large effect on melting dynamics, at least within the Azores islands.
Global, seasonal, and local time variations of ion density structure at the low‐latitude ionosphere and their relationship to the postsunset equatorial irregularity occurrences
Authors: Su S.‐Y. , Chen M. Q. , Chao C. K. , Liu C. H.
Published: February 2010

Seasonal and longitudinal (s/l) variations of ion density structure near 600 km altitude in the low‐latitude ionosphere, observed by ROCSAT‐1 for two similar high solar activity years of 2000 and 2002, are examined in five different local time (LT) sectors. The gross features in the s/l variations of density structure during the daytime are very similar to each other in these 2 years. A reproducibility of the daytime density structure can thus be assumed, including the shape of equatorial ionization anomaly (EIA), for similar solar flux input. The nighttime structure during the solstice shows a shape‐preserving decay in the latitudinal variation and maintains similar density level for these 2 years. In contrast, the nighttime structure in the equinox indicates noticeable differences in the 2 years. A strong global transport effect that exists in the solstice can be identified as the cause of such difference in density structure between the solstice and the equinox. The model results from both the 2006 International Reference Ionosphere model and the thermosphere ionosphere electrodynamics general circulation model cannot reproduce the global, seasonal, and local time (LT) variations of the low‐latitude ionospheric structure observed by ROCSAT. The observed longitudinal variation of the crest‐to‐trough ratio of the average background EIA structure in the 1800–1900 LT sector fails to correlate with the longitudinal variation of the postsunset equatorial irregularity occurrences in a season. There is also no correlation found between the seasonal variations of the crest‐to‐trough ratio and the irregularity occurrence at almost all longitudes, except at the longitudes of South America‐Atlantic sector where some correlation seems to exist.
Radiative impacts of clouds in the tropical tropopause layer
Authors: Yang Qiong , Fu Qiang , Hu Yongxiang
Published: February 2010

We quantify the seasonal and spatial variations of cloud radiative impacts in the tropical tropopause layer (TTL) by using cloud retrievals from Cloud‐Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO), International Satellite Cloud Climatology Project (ISCCP) and CloudSat. Over the convective regions including Western Pacific, Africa, South America, and South Asia, we find pronounced solar heating and infrared cooling in the lower part of the TTL (<∼16 km). The solar heating weakens above 16 km and nearly diminishes at 18 km, whereas the infrared cooling extends vertically throughout the TTL. The net cloud radiative forcing, which is the summation of cloud solar and infrared radiative forcing, has heating below ∼16 km and turns to mostly cooling above 17 km. The net cloud radiative heating over the convective regions is mainly contributed from solar radiation, whereas the weak net cloud radiative heating surrounding these regions is due to infrared heating. To further examine the impacts of different cloud types in the TTL, we classified TTL clouds in terms of cloud optical depths (τ) as thin cirrus (τ < 0.3), thick cirrus (0.3 ≤ τ < 3), and opaque clouds (τ ≥ 3). In the solar part, thin and thick cirrus play a relatively small role and the impact of cloud‐free air above clouds is negligible. The solar heating is dominantly contributed from the solar absorption near the top of opaque clouds. In the infrared part, the thick cirrus heating is mainly confined over the convective regions in the lower part of TTL while the thin cirrus infrared heating is more prevalent both vertically and horizontally in the TTL, which is the dominant infrared heating source. The infrared cooling in cloud‐free air above clouds is dominant above 17 km, whereas the infrared cooling near the top of opaque clouds is dominant below. Despite the infrared heating effects of thin and thick cirrus clouds, the infrared cooling from the opaque cloud top and cloud‐free air above clouds outweighs the heating effects so that the ensemble mean cloud infrared radiative forcing is mostly cooling except outside the convective regions.
25‐Hydroxyvitamin D Concentration Correlates With Insulin‐Sensitivity and BMI in Obesity
Authors: Muscogiuri Giovanna , Sorice Gian Pio , Prioletta Annamaria , Policola Caterina , Della Casa Silvia , Pontecorvi Alfredo , Giaccari Andrea
Published: February 2010

The prevalence of hypovitaminosis D is high among obese subjects. Further, low 25‐hydroxyvitamin D (25(OH)D) concentration has been postulated to be a risk factor for type 2 diabetes, although its relation with insulin‐sensitivity is not well investigated. Thus, we aimed to investigate the relationship between 25(OH)D concentration and insulin‐sensitivity, using the glucose clamp technique. In total, 39 subjects with no known history of diabetes mellitus were recruited. The association of 25(OH)D concentration with insulin‐sensitivity was evaluated by hyperinsulinemic euglycemic clamp. Subjects with low 25(OH)D (<50 nmol/l) had higher BMI (P = 0.048), parathyroid hormone (PTH) (P = 0.040), total cholesterol (P = 0.012), low‐density lipoprotein (LDL) cholesterol (P = 0.044), triglycerides (P = 0.048), and lower insulin‐sensitivity as evaluated by clamp study (P = 0.047). There was significant correlation between 25(OH)D and BMI (r = −0.58; P = 0.01), PTH (r = −0.44; P < 0.01), insulin‐sensitivity (r = 0.43; P < 0.01), total (r = −0.34; P = 0.030) and LDL (r = −0.40; P = 0.023) (but not high‐density lipoprotein (HDL)) cholesterol, and triglycerides (r = 0.45; P = 0.01). Multivariate analysis using 25(OH)D concentration, BMI, insulin‐sensitivity, HDL cholesterol, LDL cholesterol, total cholesterol, and triglycerides, as the cofactors was performed. BMI was found to be the most powerful predictor of 25(OH)D concentration (r = −0.52; P < 0.01), whereas insulin‐sensitivity was not significant. Our study suggested that there is no cause–effect relationship between vitamin D and insulin‐sensitivity. In obesity, both low 25(OH)D concentration and insulin‐resistance appear to be dependent on the increased body size.
Similarity in Percent Body Fat Between White and Vietnamese Women: Implication for a Universal Definition of Obesity
Authors: Ho‐Pham Lan T. , Lai Thai Q. , Nguyen Nguyen D. , Barrett‐Connor Elizabeth , Nguyen Tuan V.
Published: February 2010

It has been widely assumed that for a given BMI, Asians have higher percent body fat (PBF) than whites, and that the BMI threshold for defining obesity in Asians should be lower than the threshold for whites. This study sought to test this assumption by comparing the PBF between US white and Vietnamese women. The study was designed as a comparative cross‐sectional investigation. In the first study, 210 Vietnamese women ages between 50 and 85 were randomly selected from various districts in Ho Chi Minh City (Vietnam). In the second study, 419 women of the same age range were randomly selected from the Rancho Bernardo Study (San Diego, CA). In both studies, lean mass (LM) and fat mass (FM) were measured by dual‐energy X‐ray absorptiometry (DXA) (QDR 4500; Hologic). PBF was derived as FM over body weight. Compared with Vietnamese women, white women had much more FM (24.8 ± 8.1 kg vs. 18.8 ± 4.9 kg; P < 0.0001) and greater PBF (36.4 ± 6.5% vs. 35.0 ± 6.2%; P = 0.012). However, there was no significant difference in PBF between the two groups after matching for BMI (35.1 ± 6.2% vs. 35.0 ± 5.7%; P = 0.87) or for age and BMI (35.6 ± 5.1% vs. 35.8 ± 5.9%; P = 0.79). Using the criteria of BMI ≥30, 19% of US white women and 5% of Vietnamese women were classified as obese. Approximately 54% of US white women and 53% of Vietnamese women had their PBF >35% (P = 0.80). Although white women had greater BMI, body weight, and FM than Vietnamese women, their PBF was virtually identical. Further research is required to derive a more appropriate BMI threshold for defining obesity for Asian women.
Will Work for Snack Food: The Association of BMI and Snack Reinforcement
Authors: Giesen Janneke C.A.H. , Havermans Remco C. , Douven Anne , Tekelenburg Mignon , Jansen Anita
Published: February 2010

It has been suggested that for overweight and obese individuals high‐calorie foods are more reinforcing than for normal‐weight individuals. It has already been shown that in contrast to sedentary activities, snack food is more reinforcing for obese women, relative to normal‐weight women. However, it is unclear whether overweight/obese individuals are more sensitive to the reinforcing value of food in general or more specifically to the reinforcing value of high‐calorie foods. This was tested in the present study, with overweight/obese and normal‐weight individuals performing a concurrent schedules task, which measures how hard someone is prepared to work for high‐calorie snacks compared to low‐calorie foods (e.g., fruits, vegetables), when both foods are equally liked. By gradually increasing the amount of work required to earn snacks, the relative‐reinforcing value of snacks was determined. As hypothesized, overweight/obese individuals work harder for high‐calorie snacks compared to normal‐weight individuals.
Beyond the BMI: The Search for Better Guidelines for Bariatric Surgery
Authors: Pories Walter J. , Dohm Lynis G. , Mansfield Christopher J.
Published: February 2010

The application of the BMI of ≥35 as the major prerequisite for access to bariatric surgery is no longer appropriate because the index, now incorporated in the requirements of Medicare, Medicaid and most private carriers, does not reflect the degree or distribution of adiposity, it discriminates unfairly on the basis of gender, race, age, fitness, and body fat composition. Further, with increasing evidence that bariatric surgery can also induce full and durable remission of such comorbidities as type 2 diabetes even in patients with BMIs <30, new guidelines must be pursued.
Adhesamine, a new synthetic molecule, accelerates differentiation and prolongs survival of primary cultured mouse hippocampal neurons
Authors: Hoshino Mitsunobu , Tsujimoto Tetsuhiro , Yamazoe Sayumi , Uesugi Motonari , Terada Sumio
Published: February 2010

Attachment to the substrate is essential for both survival and differentiation of various kinds of cells, such as neurons and epithelial cells. We recently found a small synthetic molecule, adhesamine, which boosts adhesion and growth of mammalian cells. In the present study, we applied adhesamine to primary cultured hippocampal neuronal cells and compared its effects with those of PLL (poly-L-lysine), which is widely used as a substrate for cell cultures. Neurons grown on adhesamine-coated coverslips survived for up to 1 month without a feeder layer of glial cells, and had greater viability than cells grown on PLL-coated coverslips. Morphological analysis revealed that neurons cultured with adhesamine exhibited earlier differentiation, i.e. earlier axonal outgrowth and dendritic maturation with enhanced neurite branching, than neurons cultured with PLL. Synaptic formation and postsynaptic responses were evident as early as 4 days in cells cultured with adhesamine. Acceleration of differentiation is mediated by earlier activation of the signalling pathways from heparan sulfate in the extracellular matrix to both FAK (focal adhesion kinase) and MAPK (mitogen-activated protein kinase). Improved survival rates and accelerated maturation of neurons exposed to adhesamine suggest that this completely synthetic molecule may be a useful reagent for culturing neuronal cells.
Examining Relationships Among Dialect Variation, Literacy Skills, and School Context in First Grade
Authors: Terry Nicole Patton , Connor Carol McDonald , Thomas-Tate Shurita , Love Michael
Published: February 2010

Purpose

This study examined relationships between the use of nonmainstream American English dialects, literacy skills, and school environment among typically developing first graders (n= 617), of whom 48% were African American and 52% were White, in order to describe and better understand the difficulties many children from linguistically diverse backgrounds experience while learning to read.

Method

Using hierarchical linear modeling, the authors examined the linear and quadratic relationships between students' dialect variation (DVAR) and their vocabulary, phonological awareness, and word reading skills, taking into account school environment, specifically schoolwide socioeconomic status (SES).

Results

The relationships between DVAR and literacy outcomes depended on the outcome of interest and school SES. However, children’s race did not generally affect the trajectory or strength of the relationships between outcomes and dialect variation. For vocabulary and word reading, the association was nonlinear, that is, U-shaped, but this depended on school SES. For phonological awareness, a negative linear relationship was observed that did not depend on school SES.

Conclusions

The results inform theories on the relationship between DVAR and literacy achievement and suggest a more complex explanation of how nonmainstream American English dialect use might influence how young children learn to read.
Lexical–Semantic Organization in Children With Specific Language Impairment
Authors: Sheng Li , McGregor Karla K.
Published: February 2010

Purpose

To determine whether children with specific language impairment (SLI) show deficits in lexical–semantic organization and, if so, whether these deficits are commensurate with their delay in vocabulary size and whether the deficits affect all children with SLI.

Method

Fourteen children with SLI, 14 age matches (AM), and 14 expressive vocabulary matches (VM) generated 3 associations to each of 48 words. Associations were coded as semantic (e.g.,
dog
–
pet
), clang (e.g.,
cow
–
how
), or erroneous (e.g.,
spoon
–
Disney
).

Results

Relative to the AM children, children with SLI produced fewer semantic responses, more clangs, and more errors. Relative to the VM children, fewer semantic responses and more errors in the children with SLI were found in by-item analyses. Across elicitation trials, semantic responses decreased in the AM and VM children but remained stable in the SLI children. Examination of individual performance in the SLI group revealed that poor semantic performance was associated with a deficit in expressive vocabulary and a gap between receptive and expressive vocabularies.

Conclusions

Significant variability in lexical–semantic organization skills exists among children with SLI. Deficits in lexical–semantic organization were demonstrated by a subgroup of children with SLI who likely had concomitant word-finding difficulties.
Analysis of secondary particle behavior in multiaperture, multigrid accelerator for the ITER neutral beam injector
Authors: Mizuno T. , Taniguchi M. , Kashiwagi M. , Umeda N. , Tobari H. , Watanabe K. , Dairaku M. , Sakamoto K. , Inoue T.
Published: February 2010

Heat load on acceleration grids by secondary particles such as electrons, neutrals, and positive ions, is a key issue for long pulse acceleration of negative ion beams. Complicated behaviors of the secondary particles in multiaperture, multigrid (MAMuG) accelerator have been analyzed using electrostatic accelerator Monte Carlo code. The analytical result is compared to experimental one obtained in a long pulse operation of a MeV accelerator, of which second acceleration grid (A2G) was removed for simplification of structure. The analytical results show that relatively high heat load on the third acceleration grid (A3G) since stripped electrons were deposited mainly on A3G. This heat load on the A3G can be suppressed by installing the A2G. Thus, capability of MAMuG accelerator is demonstrated for suppression of heat load due to secondary particles by the intermediate grids.
Short time ion pulse extraction from the Dresden electron beam ion trap
Authors: Kentsch U. , Zschornack G. , Schwan A. , Ullmann F.
Published: February 2010

We present measurements of the extraction of short time pulses of highly charged ions (4 keV, Ar16+) from the Dresden electron beam ion trap. Thereby the dependence of the extractable ionic charge on the extraction regime was investigated. The ion extraction time was varied between 20 ns and 1 μs. Furthermore the production of carbon ions and the influence of the extraction regime on the pulse widths was investigated to obtain information about the suitability of the Dresden EBIS-A in synchrotron based particle therapy facilities.
Status report of the heavy ions source research and development for Spiral2
Authors: Thuillier T. , Lamy T. , Peaucelle C. , Sortais P.
Published: February 2010

The physics background requiring a very intense multicharged heavy ion source for Spiral2 is explained. The new Spiral2 low energy beam line dedicated to the heavy ions production and equipped with PHOENIX V2 ECRIS is presented. A status of the A-PHOENIX commissioning at 18 GHz is summarized. A new hybrid ECRIS concept with a cryogenic permanent magnet hexapole is proposed as an improvement of A-PHOENIX technology.
Permanent magnet desktop magnetic resonance imaging system with microfabricated multiturn gradient coils for microflow imaging in capillary tubes
Authors: Sahebjavaher Ramin S. , Walus Konrad , Stoeber Boris
Published: February 2010

A prototype for a desktop high-resolution magnetic resonance imaging (MRI) velocimetry instrument to characterize flow fields in a capillary tube is demonstrated. This inexpensive compact system is achieved with a 0.6 T permanent magnetic configuration (Larmor frequency of 25 MHz) and temperature compensation using off-the-shelf NdFeB permanent magnets. A triaxial gradient module with microfabricated copper coils using a lithographic fabrication process has been developed. This gradient module is capable of generating fast-switching gradients (<100 μs) with amplitudes up to 1.7 T/m using custom made current amplifiers, and was optimized for microflow imaging. The radio frequency probe is integrated with the gradient module and is driven by custom electronics. A two-dimensional (2D) cross-sectional static image of the inside of a capillary tube with an inner diameter of 1.67 mm is acquired at an in-plane spatial resolution of better than 40 μm. Time-of-flight flow measurements were also obtained using this MRI system to measure the velocity profile of water flowing at average velocities of above 50 mm/s. The flow profile for slower flow velocities was obtained using phase-encoded techniques, which provides quantitative velocity information in 2D.