bluuebunny/crossref_metadata_2025_split huggingface dataset:
Radiation coupling with two‐dimensional electron systems in the low limit of the microwave band: magnetoresistance response
Authors: Iñarrea Jesús 
Published: May 2012

AbstractWe report on a theoretical study of radiation‐induced resistance oscillations and zero‐resistance states in two‐dimensional electron systems when the irradiation frequency is very low. In this situation the photon energy is much smaller than the spacing between the Landau levels and therefore interlevel transitions are excluded. Experiments show that when these frequencies are used, resistance oscillations disappear and, instead, a strong suppression of magnetoresistance response is obtained. We apply the radiation‐driven electron orbit model concluding that the resistance suppression is a manifestation of an oscillation of very large wavelength. Under this regime we study the connection with larger frequencies and the dependence on radiation power and temperature. For high enough radiation intensity, we predict that a regime of zero‐resistance states can be reached at these low frequencies, too. The calculated results are in good agreement with experiments. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modeling epidemic data diffusion for wireless mobile networks
Authors: Islam Mohammad Towhidul , Akon Mursalin , Abdrabou Atef , Shen Xuemin (Sherman) 
Published: May 2012

ABSTRACTData/content dissemination among the mobile devices is the fundamental building block for all the applications in wireless mobile collaborative computing, known as mobile peer‐to‐peer. Different parameters such as node density, scheduling among neighboring nodes, mobility pattern, and node speed have a tremendous impact on data diffusion in a mobile peer‐to‐peer environment. In this paper, we develop analytical models for object diffusion time/delay in a wireless mobile network to apprehend the complex interrelationship among these different parameters. In the analysis, we calculate the probabilities of transmitting a single object from one node to multiple nodes using the epidemic model of spread of disease. We also incorporate the impact of node mobility, radio range, and node density in the networks into the analysis. Utilizing these transition probabilities, we estimate the expected delay for diffusing an object to the entire network both for single object and multiple object scenarios. We then calculate the transmission probabilities of multiple objects among the nodes in the wireless mobile network considering network dynamics. Through extensive simulations, we demonstrate that the proposed scheme is efficient for data diffusion in the wireless mobile network. Copyright © 2012 John Wiley & Sons, Ltd.
Synthesis, Characterization and Conductivity of Quaternary Nitrogen Surfactants Modified by the Addition of a Hydroxymethyl Substructure on the Head Group
Authors: Jordan Deborah , Tan Eng , Hegh Dylan 
Published: May 2012

AbstractTwo novel series of hydroxymethyl group‐appended quaternary nitrogen surfactants (QNSs) based on the aliphatic N‐alkyl‐trimethylammonium and aromatic N‐alkylpyridinium head groups were synthesized from the appropriate nitrogen head group precursor and 1‐bromoalkane. The QNSs were characterized using 1H and 13C nuclear magnetic resonance and infrared spectroscopy, and their purity confirmed using elemental analysis. The solution behavior of the QNSs was investigated by conductivity, assessing both the aggregation concentration as well as the amount of counter‐ion dissociation. The results showed a general decrease in the aggregation concentration for the compounds with the hydroxymethyl addition, where the pyridinium compounds were more affected than the ammonium QNSs. In contrast, the extent of counter‐ion dissociation (α) from the aggregate was slightly increased for the ammonium compounds but that of the pyridinium compounds was not generally affected by the structural modification.
Formulation of Canola‐Diesel Microemulsion Fuels and Their Selective Diesel Engine Performance
Authors: Nguyen Thu , Abraham Jacob , Ramallo Melisa , Wagner David , McLennan John 
Published: May 2012

AbstractVegetable oils have been considered as an alternative to diesel fuel due to their comparable properties and performance. However, the high viscosity of vegetable oil causes engine durability problems with long‐term usage. Vegetable oil viscosity can be reduced by blending with diesel fuel in thermodynamically stable mixtures using microemulsion fuel formulation techniques. This work focuses on the formulation of microemulsion fuels comprising diesel fuel and canola oil as the oil phase with ethanol and sec‐butanol as viscosity reducers as well as 1‐octanol and oleyl amine as surfactant/cosurfactant. Selective tests on an instrumented diesel engine were performed for formulated microemulsion fuels and No. 2 diesel fuel for comparison. The results show that formulated microemulsion fuels have fuel properties that meet the ASTM requirements for viscosity, cloud point, and pour point for biodiesel. Even more important, they have phase stability over a wide range of temperatures (−10 to 70 °C). Although all of the microemulsion fuels showed higher fuel consumption than diesel fuel, some of the microemulsion fuels had significantly reduced CO and NOx emissions as well as reduced particulates when compared to baseline diesel fuel. The research demonstrates the potential of these microemulsion fuels as alternative to neat diesel fuel.
Les inhibiteurs de la phosphodiestérase de type 5 : une révolution dans le traitement des symptômes du bas appareil urinaire?
Authors: Caremel R. , Laccarier E. , Sibert L. 
Published: May 2012

Résumé

Contexte
L’incidence des symptômes du bas appareil urinaire (SBAU) liés à une hypertrophie bénigne de prostate (HBP) augmente avec l’âge puisqu’ils touchent 50 % des patients âgés de plus de 50 ans et 90 % de ceux âgés de plus de 80 ans. La prévalence et la sévérité de la dysfonction érectile (DE) augmentent également avec l’âge. Sa prévalence est évaluée à 31,6 % dans une population générale d’adultes âgés de plus de 40 ans. Les SBAU comme la DE altèrent de façon significative la qualité de vie (QdV) des patients et de leur partenaire. Plusieurs études ont montré que les SBAU constituent un facteur de risque de DE indépendant de l’âge et des autres comorbidités. La sévérité des SBAU est corrélée à celle de la DE. Les hypothèses physiopathologiques pour expliquer le lien entre SBAU et DE sont : une augmentation du tonus sympathique, une altération du système NO/cGMP, une altération du système rho-kinase et une athéromatose pelvienne.

Objectif
Évaluer les résultats et comprendre le mécanisme d’action de l’administration d’un inhibiteur de la phosphodiestérase de type 5 (IPDE 5) sur les SBAU liés à une HBP.

Matériels et méthodes
Une revue de la littérature a été réalisée à partir des articles originaux et des articles de synthèse déjà disponibles, sélectionnés par le moteur de recherche Pubmed de la National Library of Medecine. Les mots clés utilisés pour cette recherche ont été : benign prostatic hyperplasia; cyclic nucleotide phosphodiesterase type 5; LUTS; erectile dysfunction.

Résultats
Cette revue de la littérature montre que l’administration d’un inhibiteur de la phosphodiestérase de type 5 améliore les SBAU de manière significative dans 12 essais cliniques randomisés, avec un bénéfice également sur la DE et l’absence d’effets secondaires indésirables graves rapportés.

Conclusion
Le traitement des SBAU par les IPDEs 5 semble très prometteur, même s’il ne dispose pas d’une AMM dans cette indication en France. Récemment, le tadalafil à la posologie de 5 mg a été approuvé aux États-Unis par la FDA dans les troubles mictionnels liés à l’HBP, avec ou sans DE.
Debates in transnational and science studies: a defence and illustration of the virtues of intellectual tolerance
Authors: PESTRE DOMINIQUE 
Published: May 2012

AbstractWhen considering the works produced in history of science and transnational history, one is struck by the wide range of issues covered, the profusion of ideas and analyses, the richness and variety of what is proposed. On the other hand, one is also struck by the presence of rather repetitive methodological professions of faith, of declarations of intent about categories and rules that are quite stable over time. This article considers in turn both issues. First, what we have learned in substantial terms, what these historiographical reassessments about science and transnational relations teach us, what has been displaced and what is currently being opened. In the second part, the paper considers what is at stake in these preliminary statements of principle. The article defends the idea that we are facing two major interpretative corpuses that both do count and are heuristically productive, that in practice both are often mixed by historians – but that it is intellectually and politically decisive to consider finely the epistemologies, ontologies and postures that are offered.
Cost-effectiveness and long-term effectiveness of Internet-based cognitive behaviour therapy for severe health anxiety
Authors: Hedman E. , Andersson E. , Lindefors N. , Andersson G. , Rück C. , Ljótsson B. 
Published: May 2012

BackgroundSevere health anxiety is a common condition associated with functional disability, making it a costly disorder from a societal perspective. Internet-based cognitive behaviour therapy (ICBT) is a promising treatment but no previous study has assessed the cost-effectiveness or long-term outcome of ICBT for severe health anxiety. The aim of this study was to investigate the cost-effectiveness and 1-year treatment effects of ICBT for severe health anxiety.MethodCost-effectiveness and 1-year follow-up data were obtained from a randomized controlled trial (RCT) comparing ICBT (n = 40) to an attention control condition (CC,n = 41). The primary outcome measure was the Health Anxiety Inventory (HAI). A societal perspective was taken and incremental cost-effectiveness ratios (ICERs) were calculated using bootstrap sampling.ResultsThe main ICER was −£1244, indicating the societal economic gain for each additional case of remission when administering ICBT. Baseline to 1-year follow-up effect sizes on the primary outcome measure were large (d = 1.71–1.95).ConclusionsICBT is a cost-effective treatment for severe health anxiety that can produce substantial and enduring effects.
LACK-OF-FIT TESTING OF THE CONDITIONAL MEAN FUNCTION IN A CLASS OF MARKOV MULTIPLICATIVE ERROR MODELS
Authors: Koul Hira L. , Perera Indeewara , Silvapulle Mervyn J. 
Published: May 2012

AbstractThe family of multiplicative error models, introduced by Engle (2002, Journal of Applied Econometrics 17, 425–446), has attracted considerable attention in recent literature for modeling positive random variables, such as the duration between trades at a stock exchange, volume transactions, and squared log returns. Such models are also applicable to other positive variables such as waiting time in a queue, daily/hourly rainfall, and demand for electricity. This paper develops a new method for testing the lack-of-fit of a given parametric multiplicative error model having a Markov structure. The test statistic is of Kolmogorov–Smirnov type based on a particular martingale transformation of a marked empirical process. The test is asymptotically distribution free, is consistent against a large class of fixed alternatives, and has nontrivial asymptotic power against a class of nonparametric local alternatives converging to the null hypothesis at the rate of O (n–1/2). In a simulation study, the test performed better overall than the general purpose Ljung–Box Q-test, a Lagrange multiplier type test, and a generalized moment test. We illustrate the testing procedure by considering two data examples.
Caregiving for Elders in First Nations Communities: Social System Perspective on Barriers and Challenges
Authors: Habjan Sonja , Prince Holly , Kelley Mary Lou 
Published: May 2012

RÉSUMÉCette recherche a examiné les perspectives et les expériences des membres de la communauté des Premières Nations concernant le soutien sanitaire et social pour les personnes âgées demeurant dans 13 nations du nord-ouest de l’Ontario. Des enquêtes (n = 216) et des groupes de discussion (n = 70) ont été menées en 2005 et 2006 avec les peuples autochtones aînés et leurs aidants formels et informels. Les résultats ont indiqué une forte préférence (69%) pour aider les gens à vieillir et mourir à domicile ; pourtant les obstacles et les défis existaient aux niveaux de la famille, de la communauté, du système de santé, et de la politique sociale. Il s’agissait notamment d’un manque d’aidants proches, des ressources locales humaines et de la santé, les valeurs changeants à travers de la communauté, et d’un accès limité aux services de santé provinciaux et des soins adaptés à la culture et à la sécurité des personnes âgées, tous ce qui a entravé la politique sociale et l’autonomisation des communautés. Un meilleur soutien qui permet aux personnes âgées de vieillir au sein des communautés des Premières Nations exigera des changements du système à plusieurs niveaux et à plusieurs secteurs.
Improving children's dairy food and calcium intake: can intervention work? A systematic review of the literature
Authors: Hendrie Gilly A , Brindal Emily , Baird Danielle , Gardner Claire 
Published: May 2012

AbstractObjectiveStrategies are needed to address the shortfall in children's dairy food and Ca intakes. The present review identified interventions targeting an increase in children's dairy food or Ca intakes, and determined characteristics associated with successful intervention.DesignA systematic literature search identified fourteen intervention studies, published in English, between 1990 and 2010. Studies were evaluated for study population, setting and mode of delivery, dietary targets and outcome measures, measures of intervention intensity, intervention description, the use of behaviour change techniques and intervention effectiveness.SettingInterventions targeting an increase in dairy food or Ca intake.SubjectsChildren aged 5–12 years.ResultsTen of the fourteen studies were considered to be effective. Studies focusing on encouraging intake of dairy foods or Ca alone were all effective, compared with 55 % of studies promoting dairy within the context of a healthy diet. Effective interventions tended to be higher in intensity, provide dairy foods and were delivered across a variety of settings to a range of primary targets. The number of behaviour change techniques used did not differentiate effective and ineffective interventions, but the use of taste exposure and prompting practice appeared to be important for effective intervention.ConclusionsInterventions that target an increase in children's dairy food or Ca intake could potentially increase children's dairy food intake by about one serving daily. Research conducted outside the USA is needed. The review has identified some promising strategies likely to be part of effective interventions for improving dairy and Ca intakes in countries where children's intake is insufficient.
Sociodemographic determinants of early weaning: a Finnish birth cohort study in infants with human leucocyte antigen-conferred susceptibility to type 1 diabetes
Authors: Erkkola Maijaliisa , Salmenhaara Maija , Nwaru Bright I , Uusitalo Liisa , Kronberg-Kippilä Carina , Ahonen Suvi , Veijola Riitta , Knip Mikael , Virtanen Suvi M 
Published: May 2012

AbstractObjectiveTo assess the most important sociodemographic determinants of age at introduction of complementary foods in infancy.DesignA prospective birth cohort with increased risk of type 1 diabetes, recruited between 1996 and 2004. The families completed at home a follow-up form on the age at introduction of new foods and, for each clinic visit, a structured dietary questionnaire with 3 d food records.SettingData from the Type 1 Diabetes Prediction and Prevention (DIPP) Project, Finland.SubjectsA cohort of 5991 infants (77 % of those invited) belonging to the DIPP Nutrition Study.ResultsSixty-three per cent of the infants were introduced to complementary foods, including infant formula, before the age of 4 months. The median age at introduction of infant formula was 1·5 months (range 0–18 months) and that of the first other complementary food 3·5 months (range 0·7–8 months). All sociodemographic and lifestyle factors studied were associated with the age at introduction of infant formula and/or first other complementary food. Female sex of the infant, being born in the southern region of Finland, living in a rural municipality, the presence of siblings, the mother or the father being a high-school graduate, high maternal professional education and maternal non-smoking during pregnancy predicted later introduction of complementary foods.ConclusionsCompliance was relatively poor with the current recommendations for the age of introducing complementary foods. Small-sized young families with less well-educated parents were most prone to introduce complementary foods early.
Analytical representation of the fault slip velocity from spontaneous dynamic earthquake models
Authors: Bizzarri Andrea 
Published: May 2012

We have analyzed the most relevant features of three different analytical representations of the time evolution of the cosesimic slip velocity derived from theoretical basis; the so‐called modified Yoffe function (MY), which pertains to a singular crack solution, the solution for a nonspontaneous crack obeying a position‐weakening governing equation (PR) and the solution for a 1‐D fault model subject to a linear slip‐weakening friction law (B). By considering the same input parameters, we quantitatively compare these slip velocity functions (SVF) and we found that the time evolutions of the velocity and the correspondent slip predicted by the MY and B functions are very similar, while the PR predicts a very sharp peak. Correspondingly, the PR SVF is richer in high frequency and the fall off of its spectrum at high frequencies goes roughly as ω–1.5, while those of MY and B more closely follow ω–2. Then we select two spontaneous, 3‐D, dynamic, subshear models, representing a crack‐like or a pulse‐like rupture and we account for both homogeneous and heterogeneous configurations. We then compare the three SVF in order to see how they are able to reproduce the 3‐D solutions; we also show how the input parameters of the SVF can be constrained from the results of the dynamic models. In the homogeneous cases our results indicate that the MY and the PR SVF reproduce adequately well the main features of a dynamic solution in the case of a crack‐like rupture. The PR function overestimates vpeak and the MY SVF predicts a too rapid deceleration. In the case of a pulse‐like rupture both the MY and the B SVF tend to underestimate vpeak , but all of them capture very well the final cumulated fault slip. Moreover, the B function fits better that the MY the overall behavior of the fault slip. The considered SVF are able to reproduce the spectral fall off of a 3‐D solution at intermediate frequencies (for ω < 20 Hz), the MY and the PR for a crack‐like rupture and the MY and the B SVF for a pulse‐like rupture. In particular, for ω < 10 Hz the spectral content of the B function is practically indistinguishable from that of the spontaneous pulse‐like solution. In the heterogeneous configurations the analytical functions cannot reproduce all the spectral details of the numerical solutions, but we see how it is possible to fit the overall behavior of a single pulse in fault the slip velocity time history. The thorough analysis performed in this work can contribute to the discussion about the debated choice of the source time function to be used in the kinematic models, which in turn is extremely important in the contest of hazard assessment and ground motions generation, although stress heterogeneities, geometrical irregularities, attenuation and free surface effects can definitively smear the details of the analytical functions.
Joint horizontal‐vertical anisotropic scaling, isobaric and isoheight wind statistics from aircraft data
Authors: Pinel J. , Lovejoy S. , Schertzer D. , Tuck A. F. 
Published: May 2012

Aircraft measurements of the horizontal wind have consistently found transitions from roughly k−5/3 to k−2.4 spectra at scales Δxc ranging from about 100–500 km. Since drop sondes find k−2.4spectra in the vertical, the simplest explanation is that the aircraft follow gently sloping trajectories (such as isobars) so that at large scales, they estimate vertical rather than horizontal spectra. In order to directly test this hypothesis, we used over 14500 flight segments from GPS and TAMDAR sensor equipped commercial aircraft. We directly estimate the joint horizontal‐vertical (Δx, Δz) wind structure function finding ‐ for both longitudinal and transverse components ‐ that the ratio of horizontal to vertical scaling exponents isHz ≈ 0.57 ± 0.02, close to the theoretical prediction of the 23/9D turbulence model which predicts Hz = 5/9 = 0.555…. This model also predicts that isobars and isoheight statistics will diverge after Δxc; using the observed fractal dimension of the isobars (≈1.79 ± 0.02), we find that the isobaric scaling exponents are almost exactly as predicted theoretically and Δxc ≈ 160, 125 km, (transverse, longitudinal). These results thus give strong direct support to the 23/9D scaling stratification model.
Targeted Lagrangian sampling of submesoscale dispersion at a coastal frontal zone
Authors: Schroeder K. , Chiggiato J. , Haza A. C. , Griffa A. , Özgökmen T. M. , Zanasca P. , Molcard A. , Borghini M. , Poulain P. M. , Gerin R. , Zambianchi E. , Falco P. , Trees C. 
Published: May 2012

The potential impact of rapidly‐evolving submesoscale motions on relative dispersion is at the forefront of physical oceanography, posing challenges for both observations and modeling. A persistent coastal front driven by river outflows in the North‐Western Mediterranean Sea is targeted by two observational cruises conducted in the summer of 2010. The frontal zone is sampled using drifters launched with a multi‐scale strategy consisting of modules of triplets, released on either side of the front by small boats. This experiment is original in that the submesoscale range of 100 m to 1000 m is directly targeted, and the results are expected to provide guidance for practical applications, such as prediction of the initial spreading of pollutants and biogeochemical tracers. The influence of submesoscale motions on relative dispersion is quantified using both particle mean square separation as a function of time, and scale‐dependent finite‐size Lyapunov exponents (FSLE,λ(δ)). Our main finding is the identification of a local dispersion regime with values reaching as high as λ ≈ 20 days−1 at drifter pair separation distances of δ < 100 m. This value is more than an order of magnitude greater than that obtained by drifters in the offshore Ligurian current. The Ligurian Sea circulation is modeled using a fully realistic Regional Ocean Modeling System (ROMS) with 1/60° horizontal resolution. It is found that the numerical model significantly underestimates the relative dispersion at submesoscales, indicating the need for particle dispersion parameterizations for unresolved processes.