bluuebunny/crossref_metadata_2025_split huggingface dataset:
Food insecurity and household eating patterns among vulnerable American-Indian families: associations with caregiver and food consumption characteristics
Authors: Mullany Britta , Neault Nicole , Tsingine Danielle , Powers Julia , Lovato Ventura , Clitso Lena , Massey Sheree , Talgo Adrienne , Speakman Kristen , Barlow Allison 
Published: July 2012

AbstractObjectiveTo identify factors associated with food insecurity and household eating patterns among American-Indian families with young children.DesignCross-sectional survey among households with young children that were receiving emergency food services. We collected information on food insecurity levels, household eating patterns, experiences with commercial and community food sources and demographics, and used multivariate regression techniques to examine associations among these variables.SettingFour Southwestern American-Indian reservation communities.SubjectsA total of 425 parents/caregivers of young children completed the survey.ResultsTwenty-nine per cent of children and 45 % of adults from households participating in the survey were classified as ‘food insecure’. Larger household size was associated with increased food insecurity and worse eating patterns. Older respondents were more likely than younger respondents to have children with food insecurity (relative risk = 2·19,P< 0·001) and less likely to have healthy foods available at home (relative risk = 0·45,P< 0·01). Consumption of food from food banks, gas station/convenience stores or fast-food restaurants was not associated with food insecurity levels. Respondents with transportation barriers were 1·46 times more likely to be adult food insecure than respondents without transportation barriers (P< 0·001). High food costs were significantly associated with greater likelihoods of adult (relative risk = 1·47,P< 0·001) and child (relative risk = 1·65,P< 0·001) food insecurity.ConclusionsInterventions for American-Indian communities must address challenges such as expense and limited transportation to accessing healthy food. Results indicate a need for services targeted to older caregivers and larger households. Implications for innovative approaches to promoting nutrition among American-Indian communities, including mobile groceries and community gardening programmes, are discussed.
Exploring dietary patterns, obesity and sources of bias: the Västerbotten Intervention Programme (VIP)
Authors: Nyholm Maria , Lissner Lauren , Hörnell Agneta , Johansson Ingegerd , Hallmans Göran , Weinehall Lars , Winkvist Anna 
Published: July 2012

AbstractObjectiveDietary patterns capture the overall diet and thereby provide information on how nutrients are consumed in combinations, and have been suggested to be a better method than studying single nutrients. The present study explored the relationship between dietary patterns at baseline and incidence of obesity at 10-year follow-up in women.DesignA longitudinal study using baseline measurements from 1992–1996, including food intake, medication, heredity, socio-economic status, lifestyle and measured body composition, and follow-up data collected in 2002–2006 including measured body composition.SettingData from the Västerbotten Intervention Programme (VIP) in Sweden.SubjectsA total of 6545 initially non-obese women aged 30–50 years.ResultsAmong women reporting plausible energy intakes, the ‘Fruit and vegetables cluster’ predicted the highest incidence of obesity (OR = 1·76, 95 % CI 1·11, 2·76; P = 0·015) compared with women in the other food pattern groups combined. When adjusting for metabolic factors and BMI at baseline, the risk for obesity in the ‘Fruit and vegetables cluster’ was attenuated to non-significance. In contrast, high intake of fruit per se was associated with a decreased risk of developing obesity (OR = 0·69, 95 % CI 0·51, 0·91; P = 0·010).ConclusionsDietary pattern groups identified by cluster analysis are likely to reflect characteristics in addition to diet, including lifestyle, previous and current health status and risk factors for future disease, whereas intake of fruit per se was a stable indicator and less affected by baseline characteristics. These results underscore the need for complementary methods in understanding diet–disease relationships.
Commensal microbiome effects on mucosal immune system development in the ruminant gastrointestinal tract
Authors: Taschuk Ryan , Griebel Philip J 
Published: July 2012

AbstractCommensal microflora play many roles within the mammalian gastrointestinal tract (GIT) that benefit host physiology by way of direct or indirect interactions with mucosal surfaces. Commensal flora comprises members across all microbial phyla, although predominantly bacterial, with population dynamics varying with host species, genotype, and environmental factors. Little is known, however, about the complex mechanisms regulating host–commensal interactions that underlie this mutually beneficial relationship and how alterations in the microbiome may influence host development and susceptibility to infection. Research into the gut microbiome has intensified as it becomes increasingly evident that symbiont–host interactions have a significant impact on mucosal immunity and health. Furthermore, evidence that microbial populations vary significantly throughout the GIT suggest that regional differences in the microbiome may also influence immune function within distinct compartments of the GIT. Postpartum colonization of the GIT has been shown to have a direct effect on mucosal immune system development, but information is limited regarding regional effects of the microbiome on the development, activation, and maturation of the mucosal immune system. This review discusses factors influencing the colonization and establishment of the microbiome throughout the GIT of newborn calves and the evidence that regional differences in the microbiome influence mucosal immune system development and maturation. The implications of this complex interaction are also discussed in terms of possible effects on responses to enteric pathogens and vaccines.
Cycles and cycle modulations
Authors: Brandenburg Axel , Guerrero Gustavo 
Published: July 2012

AbstractSome selected concepts of the solar activity cycle are reviewed. Cycle modulations through a stochastic α effect are being identified with limited scale separation ratios. Three-dimensional turbulence simulations with helicity and shear are compared at two different scale separation ratios. In both cases the level of fluctuations shows relatively little variation with the dynamo cycle. Prospects for a shallow origin of sunspots are discussed in terms of the negative effective magnetic pressure instability. Tilt angles of bipolar active regions are discussed as a consequence of shear rather than the Coriolis force.
Magnetic helicity fluxes and their effect on stellar dynamos
Authors: Candelaresi Simon , Brandenburg Axel 
Published: July 2012

AbstractMagnetic helicity fluxes in turbulently driven α2 dynamos are studied to demonstrate their ability to alleviate catastrophic quenching. A one-dimensional mean-field formalism is used to achieve magnetic Reynolds numbers of the order of 105. We study both diffusive magnetic helicity fluxes through the mid-plane as well as those resulting from the recently proposed alternate dynamic quenching formalism. By adding shear we make a parameter scan for the critical values of the shear and forcing parameters for which dynamo action occurs. For this αΩ dynamo we find that the preferred mode is antisymmetric about the mid-plane. This is also verified in 3-D direct numerical simulations.
Spontaneous chiral symmetry breaking in the Tayler instability
Authors: Del Sordo Fabio , Bonanno Alfio , Brandenburg Axel , Mitra Dhrubaditya 
Published: July 2012

AbstractThe chiral symmetry breaking properties of the Tayler instability are discussed. Effective amplitude equations are determined in one case. This model has three free parameters that are determined numerically. Comparison with chiral symmetry breaking in biochemistry is made.
The Ni I lines in the solar spectrum
Authors: Vieytes Mariela C. , Mauas Pablo J. D. , Fontenla Juan M. 
Published: July 2012

AbstractThe stratosphere is the region where the ozone chemistry is important for the balance of energy, and radiation in the near UV plays a fundamental role in the creation and destruction of ozone. However, the radiation in this range of wavelength has not been very well modeled. One of the most important elements, according to its abundance in the solar atmosphere, that contribute to the emission and absorption of radiation in the spectral range between 1900 and 3900 Å, is neutral nickel (Ni I). In this work we improve the atomic model of this element, taking into account 490 lines over the spectrum. We solve these lines in NLTE using the Solar Radiation Physical Modeling (SRPM) program and compare the results with observation of the quiet sun spectrum.
Global magnetic fields: variation of solar minima
Authors: Tlatov Andrey G. , Obridko Vladimir N. 
Published: July 2012

AbstractThe topology of the large-scale magnetic field of the Sun and its role in the development of magnetic activity were investigated using Hα charts of the Sun in the period 1887-2011. We have considered the indices characterizing the minimum activity epoch, according to the data of large-scale magnetic fields. Such indices include: dipole-octopole index, area and average latitude of the field with dominant polarity in each hemisphere and others. We studied the correlation between these indices and the amplitude of the following sunspot cycle, and the relation between the duration of the cycle of large-scale magnetic fields and the duration of the sunspot cycle.The comparative analysis of the solar corona during the minimum epochs in activity cycles 12 to 24 shows that the large-scale magnetic field has been slow and steadily changing during the past 130 years. The reasons for the variations in the solar coronal structure and its relation with long-term variations in the geomagnetic indices, solar wind and Gleissberg cycle are discussed.We also discuss the origin of the large-scale magnetic field. Perhaps the large-scale field leads to the generation of small-scale bipolar ephemeral regions, which in turn support the large-scale field. The existence of two dynamos: a dynamo of sunspots and a surface dynamo can explain phenomena such as long periods of sunspot minima, permanent dynamo in stars and the geomagnetic field.
The 3D solar minimum with differential emission measure tomography
Authors: Vásquez Alberto M. , Frazin Richard A. , Huang Zhenguang , Manchester Ward B. , Shearer Paul 
Published: July 2012

AbstractDifferential emission measure tomography (DEMT) makes use of extreme ultraviolet (EUV) image series to deliver two products: a) the three-dimensional (3D) reconstruction of the coronal emissivity in the instrumental bands, and b) the 3D distribution of the local differential emission measure (LDEM). The LDEM allows, in turn, construction of 3D maps of the electron density and temperature distribution. DEMT is being currently applied to the space-based EUV imagers, allowing reconstruction of the inner corona in the height range 1.00 to 1.25 R⊙. In this work we applied DEMT to different Carrington Rotations corresponding to the last two solar Cycle minima. To reconstruct the 2008 minimum we used data taken by the Extreme UltraViolet Imager (EUVI), on board the Solar TErrestrial RElations Observatory (STEREO) spacecraft, and to reconstruct the 1996 minimum we used data taken by the Extreme ultraviolet Imaging Telescope (EIT), on board the Solar and Heliospheric Observatory (SOHO). We show here comparative results, discussing the observed 3D density and temperature distributions in the context of global potential magnetic field extrapolations. We also compare the DEMT results with other observational and modeling efforts of the same periods.
Coronal transients during two solar minima: their source regions and interplanetary counterparts
Authors: Cremades Hebe , Mandrini Cristina H. , Dasso Sergio 
Published: July 2012

AbstractWe have investigated two full solar rotations belonging to two distinct solar minima, in the frame of two coordinated observational and research campaigns. The nearly uninterrupted gathering of solar coronal data since the beginning of the SOHO era offers the exceptional possibility of comparing two solar minima for the first time, with regard to coronal transients. This study characterizes the variety of outward-travelling transients observed in the solar corona during both time intervals, from very narrow jet-like events to coronal mass ejections (CMEs). Their solar source regions and ensuing interplanetary structures were identified and characterized. Multi-wavelength images from the space missions SOHO, Yohkoh and STEREO, and ground-based observatories were studied for coronal ejecta and their solar sources, while in situ data registered by the ACE spacecraft were inspected for interplanetary CMEs and magnetic clouds. Instrumental aspects such as dissimilar resolution, cadence, and fields of view are considered in order to discern instrumentally-driven disparities from inherent differences between solar minima.
Dynamical evolution of anisotropies of the solar wind magnetic turbulent outer scale
Authors: Ruiz M. E. , Dasso S. , Matthaeus W. H. , Marsch E. , Weygand J. M. 
Published: July 2012

AbstractThe evolution of the turbulent properties in the solar wind, during the travel of the parcels of fluid from the Sun to the outer heliosphere still has several unanswered questions. In this work, we will present results of an study on the dynamical evolution of turbulent magnetic fluctuations in the inner heliosphere. We focused on the anisotropy of the turbulence integral scale, measured parallel and perpendicular to the direction of the local mean magnetic field, and study its evolution according to the aging of the plasma parcels observed at different heliodistances. As diagnostic tool we employed single-spacecraft correlation functions computed with observations collected by Helios 1 & 2 probes over nearly one solar cycle. Our results are consistent with driving modes with wave-vectors parallel to the direction of the local mean magnetic field near the Sun, and a progressive spectral transfer of energy to modes with perpendicular wave-vectors. Advances made in this direction, as those presented here, will contribute to our understanding of the magnetohydrodynamical turbulence and Alfvénic-wave activity for this system, and will provide a quantitative input for models of charged solar and galactic energetic particles propagation and diffusion throughout the inner heliosphere.
Geomagnetic effects on cosmic ray propagation for different conditions
Authors: Masías-Meza Jimmy J. , Bertou Xavier , Dasso Sergio 
Published: July 2012

AbstractThe geomagnetic field (Bgeo) sets a lower cutoff rigidity (Rc) to the entry of cosmic particles to Earth which depends on the geomagnetic activity. From numerical simulations of the trajectory of a proton (performed with the MAGCOS code) in the Bgeo, we use backtracking to analyze particles arriving at the Auger Observatory location. We determine the asymptotic trajectories and the values of Rc in different incidence directions. Simulations were done using several models of Bgeo that emulate different geomagnetic conditions.
Earth–directed coronal mass ejections and their geoeffectiveness during the 2007–2010 interval
Authors: Oprea Constantin , Mierla Marilena , Maris Georgeta 
Published: July 2012

AbstractIn this study we analyse the coronal mass ejections (CMEs) directed towards the Earth during the interval 2007–2010, using the data acquired by STEREO mission and those provided by SOHO, ACE and geomagnetic stations. A study of CMEs kinematics is performed. This is correlated with CMEs interplanetary manifestations and their geomagnetic effects, along with the energy transfer flux into magnetosphere (the Akasofu coupling function). The chosen interval that is practically coincident with the last solar minimum, offered us a good opportunity to link and analyse the chain of phenomena from the Sun to the terrestrial magnetosphere in an attempt to better understand the solar and heliospheric processes that can cause major geomagnetic storms.
Evolution of a very complex active region during the decay phase of Cycle 23
Authors: Poisson Mariano , Fuentes Marcelo López , Mandrini Cristina H. , Démoulin Pascal , Pariat Etienne 
Published: July 2012

AbstractWe study the emergence and evolution of AR NOAA 10314, observed on the solar disk during March 13-19, 2003. This extremely complex AR is of particular interest due to its unusual magnetic flux distribution and the clear rotation of the polarities of a δ-spot within the AR. Using SOHO/MDI magnetograms we follow the evolution of the photospheric magnetic flux to infer the morphology of the structure that originates the AR. We determine the tilt angle variation for the δ-spot and find a counter-clockwise rotation corresponding to a positive writhed flux tube. We compute the magnetic helicity injection and the total accumulated helicity in the AR and find a correlation with the observed rotation.
Stellar cycles: general properties and future directions
Authors: Giampapa Mark S. 
Published: July 2012

AbstractWe discuss the general properties of stellar cycles with emphasis on their amplitudes as a function of stellar parameters, particularly those stellar characteristics relevant to dynamo-driven magnetic activity. We deduce an empirical scaling relation between cycle frequency and differential rotation based on previously established empirical relations. We also compare the recent Cycle 23 to cycles in solar-type stars. We find that the extended minimum of Cycle 23 resembled in its Ca II H & K emission at minimum the mean levels of activity seen in stars with no cycles.
Modulated stellar and solar cycles: parallels and differences
Authors: Oláh K. , van Driel-Gesztelyi L. , Strassmeier K. G. 
Published: July 2012

AbstractWe present examples of activity cycle timescales on different types of stars from lowmass dwarfs to more massive giants, with wide-ranging rotation rates, and compare the observed cyclicities to the irradiance based solar cycle and its modulations. Using annual spectral solar irradiance in wavelength bands typical for stellar observations reconstructed by Shapiro et al. (2011), a direct comparison can be made between cycle timescales and amplitudes derived for the Sun and the stars. We show that cycles on multiple timescales, known to be present in solar activity, also show up on stars when the dataset is long enough to allow recognition. The cycle lengths are not fixed, but evolve – gradually during some periods but there are also changes on short timescales. In case the activity is dominated by spots, i.e., by cooler surface features, the star is redder when fainter, whereas other type of activity make the stars bluer when the activity is higher. We found the Sun to be a member of the former group, based on reconstructed spectral irradiance data by Shapiro et al. (2011).
The solar wind in time
Authors: Linsky Jeffrey L. , Wood Brian E. , Redfield Seth 
Published: July 2012

AbstractWe describe our method for measuring mass loss rates of F–M main sequence stars with high-resolution Lyman-α line profiles. Our diagnostic is the extra absorption on the blue side the interstellar hydrogen absorption produced by neutral hydrogen gas in the hydrogen walls of stars. For stars with low X-ray fluxes, the correlation of observed mass loss rate with X-ray surface flux and age predicts the solar wind mass flux between 700 Myr and the present.
Magnetic activity of cool stars in the Hertzsprung-Russell diagram
Authors: Schmitt J. H. M. M. 
Published: July 2012

AbstractI review the X-ray emission from cool stars with outer convection zones in comparison to the Sun with a focus on the properties of low-activity stars. I present the recent results of long-term X-ray monitoring which demonstrate the existence of X-ray cycles on stars with known calcium cycles. The evidence of a minimum stellar X-ray flux is presented and arguments are put forward for the view that the Sun in its extended minimum between 2008 - 2009 behaved very much like a Maunder-minimum Sun.
Semi-empirical modelling of stellar magnetic activity
Authors: Valio Adriana 
Published: July 2012

AbstractSince Galileo, for four hundred years, dark spots have been observed systematically on the surface of the Sun. The monitoring of the sunspot number has shown that their number varies periodically every 11 years. This is the well-known solar activity cycle that is caused by the periodic changes of the magnetic field of the Sun. Not only do spots vary in number on a timescale of a decade, but the total luminosity and other signatures of activity such as flares and coronal mass ejections also increase and decrease with the 11-year cycle. Still unexplained to the present date are periods of decades with almost an absence of activity, where the best known example is the Maunder Minimum. Other stars also exhibit signs of cyclic activity, however the level of activity is usually thousand times higher than the solar one. Obviously, this is due to the difficulty of observing activity at the solar level on most stars. Presently, a method has been developed to detect and study individual solar like spots on the surface of planet-harbouring stars. As the planet eclipses dark patches on the surface of the star, a detectable signature can be observed in the light curve of the star during the transit. The study of a different variety of stars allows for a better understanding of magnetic cycles and the evolution of stars.
12 years of stellar activity observations in Argentina
Authors: Mauas P. J. D. , Buccino A. , Díaz R. , Vieytes M. , Petrucci R. , Jofre E. , Abrevaya X. , Luoni M. L. , Valenzuela P. 
Published: July 2012

AbstractWe present an observational program we started in 1999, to systematically obtain mid-resolution spectra of late-type stars, to study in particular chromospheric activity. In particular, we found cyclic activity in four dM stars, including Prox-Cen. We directly derived the conversion factor that translates the known S index to flux in the Ca II cores, and extend its calibration to a wider spectral range. We investigated the relation between the activity measurements in the calcium and hydrogen lines, and found that the usual correlation observed is the product of the dependence of each flux on stellar color, and it is not always preserved when simultaneous observations of a particular star are considered. We also used our observations to model the chromospheres of stars of different spectral types and activity levels, and found that the integrated chromospheric radiative losses, normalized to the surface luminosity, show a unique trend for G and K dwarfs when plotted against the S index.
A statistical analysis of Hα-Ca II relation for solar-type stars of different activity levels
Authors: Buccino Andrea P. , Vieytes Mariela C. , Mauas Pablo J. D. 
Published: July 2012

AbstractBased on our large spectral database obtained at CASLEO Argentinian Observatory, we analyzed the relation between simultaneous measurements of Hα and Ca ii H+K fluxes. Although the correlation between both proxies is positive for the solar case, in 2007 our group found that while some stars exhibit correlations between Hα and the Ca ii lines, the slopes change from star to star, including cases where no correlation was found. To discern if this flux-flux relation depends on the level of activity of the star and if it is associated with the distribution of active regions in the stellar atmosphere, in this work we analyze the relation between Hα-Ca ii fluxes for the whole set of 44 G dwarf stars and individually for a subset of several solar-type stars of different level of activity.