bluuebunny/crossref_metadata_2025_split huggingface dataset:
Supergranulation and its Activity Dependence
Authors: Paniveni U. , Krishan V. , Singh J. , Srikanth R. 
Published: August 2011

AbstractWe study the complexity of supergranular cells using the intensity patterns obtained at the Kodaikanal solar observatory during the solar maximum. Our data consists of visually identified supergranular cells, from which a fractal dimension D is obtained according to the relation P ∝ AD/2 where A is the area and P is the perimeter of the cells. We find a difference in the fractal dimension between the active and the quiet region cells which is conjectured to be due to the magnetic activity level.
3D MHD modelling of a chromosphere above the sun's convective zone
Authors: Pinto Rui , Brun Sacha 
Published: August 2011

AbstractWe report on the extension of the ASH code to include an atmospheric stable layer (i.e not convective). This layer is meant to model the sun's chromosphere within the anelastic approximation limits while coping with the wide range of densities, time and spatial scales between r = 0.7 R⊙ and r = 1.03 R⊙. Convective overshoot into the stable atmospheric layer is observed in a region ~ 0.01 R⊙ thick, exciting waves which propagate upwards into the atmosphere.
Modelling turbulent fluxes due to thermal convection in rectilinear shearing flow
Authors: Smolec Radoslaw , Houdek Günter , Gough Douglas 
Published: August 2011

AbstractWe revisit a phenomenological description of turbulent thermal convection along the lines proposed originally by Gough (1965) in which eddies grow solely by extracting energy from the unstably stratified mean state and are subsequently destroyed by internal shear instability. This work is part of an ongoing investigation for finding a procedure to calculate the turbulent fluxes of heat and momentum in the presence of a shearing background flow in stars.
Variation in convective properties across the HR diagram
Authors: Tanner Joel , Basu Sarbani , Demarque Pierre , Robinson Frank 
Published: August 2011

AbstractWe perform 3D radiative hydrodynamic simulations to study convection in low-mass main-sequence stars with the aim of improving stellar models. Comparing models from a 0.90 M⊙ evolutionary track with 3D simulations reveals distinct differences between simulations and mixing length theory. The simulations show obvious structural differences throughout the superadiabatic layer where convection is inefficient at transporting energy. The discrepancy between MLT and simulation changes as the star evolves and the dynamical effects of turbulence increase. Further, the simulations reveal a T-tau relation that is sensitive to the strength of the turbulence, which is in contrast to 1D stellar models that use the same T-tau relation across the HR diagram.
Using simulations of solar surface convection as boundary conditions on global simulations
Authors: Trampedach Regner , Augustson Kyle 
Published: August 2011

AbstractDirect numerical simulations of convective stellar envelopes, are divided between two different physical regimes, that are rather difficult to reconcile — at least with the computational power of present-day computers. This paper outlines an attempt at bridging the gap between surface and interior simulations of convection.
Numerical simulations of the circumstellar medium of massive binaries
Authors: van Marle Allard Jan , Keppens Rony 
Published: August 2011

AbstractWe have made 3-D models of the collision of binary star winds and followed their interaction over multiple orbits. This allows us to explore how the wind-wind interaction shapes the circumstellar environment. Specifically, we can model the highly radiative shock that occurs where the winds collide. We find that the shell that is created at the collision front between the two winds can be highly unstable, depending on the characteristics of the stellar winds.
Recurrent flux emergence from dynamo-generated fields
Authors: Warnecke Jörn , Brandenburg Axel 
Published: August 2011

Abstractwe investigate the emergence of a large-scale magnetic field. This field is dynamo-generated by turbulence driven with a helical forcing function. Twisted arcade-like field structures are found to emerge in the exterior above the turbulence zone. Time series of the magnetic field structure show recurrent plasmoid ejections.
Carbonaceous meteorites contain a wide range of extraterrestrial nucleobases
Authors: Callahan Michael P. , Smith Karen E. , Cleaves H. James , Ruzicka Josef , Stern Jennifer C. , Glavin Daniel P. , House Christopher H. , Dworkin Jason P. 
Published: August 2011

All terrestrial organisms depend on nucleic acids (RNA and DNA), which use pyrimidine and purine nucleobases to encode genetic information. Carbon-rich meteorites may have been important sources of organic compounds required for the emergence of life on the early Earth; however, the origin and formation of nucleobases in meteorites has been debated for over 50 y. So far, the few nucleobases reported in meteorites are biologically common and lacked the structural diversity typical of other indigenous meteoritic organics. Here, we investigated the abundance and distribution of nucleobases and nucleobase analogs in formic acid extracts of 12 different meteorites by liquid chromatography–mass spectrometry. The Murchison and Lonewolf Nunataks 94102 meteorites contained a diverse suite of nucleobases, which included three unusual and terrestrially rare nucleobase analogs: purine, 2,6-diaminopurine, and 6,8-diaminopurine. In a parallel experiment, we found an identical suite of nucleobases and nucleobase analogs generated in reactions of ammonium cyanide. Additionally, these nucleobase analogs were not detected above our parts-per-billion detection limits in any of the procedural blanks, control samples, a terrestrial soil sample, and an Antarctic ice sample. Our results demonstrate that the purines detected in meteorites are consistent with products of ammonium cyanide chemistry, which provides a plausible mechanism for their synthesis in the asteroid parent bodies, and strongly supports an extraterrestrial origin. The discovery of new nucleobase analogs in meteorites also expands the prebiotic molecular inventory available for constructing the first genetic molecules.
Are athletes burning out with passion?
Authors: Gustafsson Henrik , Hassmén Peter , Hassmén Nathalie 
Published: August 2011

AbstractPassion is a strong motivational force towards an activity considered very important, possibly to the extent that the activity forms a part of an individual's identity. Two forms of passion, harmonious and obsessive, are thought to lead to different cognitive and affective responses. Although being passionate about sport appears to be important from a motivational perspective, it possibly also increases the risk for burnout, which is a negative consequence blamed partly on too much training and inadequate recovery. The question voiced in this study is whether harmonious passion and obsessive passion pose equal risks for burnout. Participants were 94 female and 164 male competitive athletes from 21 sports. The results, analysed using partial correlation and multivariate analyses of variance, showed that athletes with an obsessive passion scored higher on a burnout inventory than did harmoniously passionate athletes. Obsessively passionate athletes also scored higher on perceived stress and negative affect, and lower on positive affect. These findings support the assumption that even though the two forms of passion may be an integral part of elite sports, athletes scoring high on obsessive passion may be at greater risk of developing burnout than more harmoniously passionate athletes. Burning bright and burning out can thus be seen as two potential consequences for athletes driven by passion. Athletes and coaches who are aware of this may be better equipped to avoid the potential negative consequences associated with too much stress and too little recovery.
Do Consumer Responses to Media Food Safety Information Last?
Authors: Dillaway Robin , Messer Kent D. , Bernard John C. , Kaiser Harry M. 
Published: August 2011

AbstractUsing experimental methods with adult subjects from the mid‐Atlantic region of the United States, this research examines both the short‐ and longer‐term impacts of media information on consumer purchasing behavior. Subjects in the treatment group were given food safety information about poultry from a popular consumer magazine. Willingness to pay (WTP) estimates were then elicited for two types of chicken breasts: (1) a leading‐brand that was identified in the information treatment as having a high incidence of Campylobacter and Salmonella bacteria; and (2) a lesser known brand, which was reported as being relatively free of harmful bacteria. Results indicated that both negative and positive food safety information significantly impacted consumers' WTP for safer chicken compared to the reportedly less‐safe leading‐brand chicken. These changes in behavior persisted throughout the seven‐week study period.
The Economics of Food Insecurity in the United States
Authors: Gundersen Craig , Kreider Brent , Pepper John 
Published: August 2011

AbstractFood insecurity is experienced by millions of Americans and has increased dramatically in recent years. Due to its prevalence and many demonstrated negative health consequences, food insecurity is one of the most important nutrition‐related public health issues in the U.S. In this article, we address three questions where economic insights and models have made important contributions: What are the determinants of food insecurity?; What are the causal effects of food insecurity on health outcomes?; and What is the impact of food assistance programs on food insecurity? We conclude with a discussion of the policy implications of the answers to these questions and future research opportunities in this research venue.
Development of New Method for Extraction of α‐Zein from Corn Gluten Meal Using Different Solvents
Authors: Anderson Timothy J. , Lamsal Buddhi P. 
Published: August 2011

ABSTRACTA modified procedure for the extraction of α‐zein from corn gluten meal was developed and compared against a commercial extraction method. The modification involved raising the concentration of alcohol in solvent and removing the precipitate by centrifugation. Five organic solvent mixtures were compared using the modified extraction procedure developed along with the reductant sodium bisulfite and NaOH. The modified procedure precipitated most of the non‐α‐zein protein solids by increasing the concentration of alcohol. The supernatant had α‐zein‐rich fraction, resulting in higher yield of α‐zein than the commercial method when cold precipitated. The commercial extraction procedure had a zein yield of 23% and protein purity of 28% using 88% 2‐propanol solvent. The three best solvents, 70% 2‐propanol, 55% 2‐propanol, and 70% ethanol, yielded ≈35% of zein at protein purity of 44% using the modified extraction procedure. Zeins extracted using the novel method were lighter in color than the commercial method. Densitometry scans of SDS‐PAGE of α‐zein‐rich solids showed relatively large quantities of α‐zein with apparent molecular weights of 19,000 and 22,000 Da. The α‐zein‐rich solids also had small amounts of δ‐zein (10,000 Da) because it shares similar solubility properties to α‐zein. A solvent mixture with 70% 2‐propanol, 22.5% glycerol, and 7.5% water extracted significantly less zein (≈33%) compared to all other solvents and had α‐zein bands that differed in appearance and contained little to no δ‐zein.
Twin‐Screw Extrusion Processing of Rainbow Trout (Oncorhynchus mykiss) Feeds Using Various Levels of Corn‐Based Distillers Dried Grains with Solubles (DDGS)
Authors: Ayadi Ferouz Y. , Muthukumarappan K. , Rosentrater Kurt A. , Brown Michael L. 
Published: August 2011

ABSTRACTIncreasing demand for seafood products and rising demand for fish meal for commercial fish feeds is driving the search for effective alternative protein sources. Twin‐screw extrusion trials were conducted to study the production of nutritionally balanced feeds for rainbow trout fingerlings (Oncorhynchus mykiss). Six isocaloric (≈4.61 kcal/g) ingredient blends with a target protein content of >45% db were formulated with 0, 10, 20, 30, 40, and 50% distillers dried grains with solubles (DDGS) and other feed ingredients. The moisture contents of the diets were initially adjusted to 5–7% db, and then extruded at 250 rpm using dual 1.9 mm dies with varying amounts of steam (7.2–7.7 kg/hr) injected into the conditioner and water (4.3–6.5 kg/hr) into the extruder. Mass flow rates, moisture contents, and temperatures were measured during processing and moisture content, water activity, unit density, bulk density, expansion ratio, compressive strength, compressive modulus, pellet durability index, water stability, and color were analyzed to quantify the effects of varying DDGS content on the extrudate physical properties. Significant differences (P < 0.05) among the blends were observed for color and bulk density for both the raw and extruded materials, respectively, and for the unit density and pellet durability index of the extruded products. There were also significant changes in redness and yellowness, but only minor changes in brightness, among the final products with increasing DDGS content. The compressive strength of the extrudates increased significantly with increasing DDGS. Expansion ratio of all pellets was low. All extruded diets achieved very good water stability.
Dosing algorithm to target a predefined AUC in patients with primary central nervous system lymphoma receiving high dose methotrexate
Authors: Joerger Markus , Ferreri Andrés J. M. , Krähenbühl Stephan , Schellens Jan H. M. , Cerny Thomas , Zucca Emanuele , Huitema Alwin D. R. 
Published: August 2011

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT• High dose methotrexate (HDMTX) is the most effective drug in treating primary central nervous system lymphoma (PCNSL).• While interoccasion variability of MTX elimination is moderate, interindividual variability is considerable and unpredictable.• MTX dose intensity is important in patients with PCNSL to allow for an optimal clinical outcome.• No dosing algorithm has yet been defined to individualize HDMTX dose and allow for targeting a prespecified dose intensity of the drug in patients with PCNSL.WHAT THIS STUDY ADDS• The present simulation study shows that a simple and practical dosing algorithm is able to improve the proportion of patients within a prespecified target AUCMTX.• Using this dosing algorithm, 71% of the patients received a MTX dose that was higher than the standard (500 mg m−2 over 15 min followed by 3000 mg m−2 over 3 h), while 11% of the patients received a dose that was lower than standard.AIM There is no consensus regarding optimal dosing of high dose methotrexate (HDMTX) in patients with primary CNS lymphoma. Our aim was to develop a convenient dosing algorithm to target AUCMTX in the range between 1000 and 1100 µmol l−1 h.METHODS A population covariate model from a pooled dataset of 131 patients receiving HDMTX was used to simulate concentration–time curves of 10 000 patients and test the efficacy of a dosing algorithm based on 24 h MTX plasma concentrations to target the prespecified AUCMTX. These data simulations included interindividual, interoccasion and residual unidentified variability. Patients received a total of four simulated cycles of HDMTX and adjusted MTX dosages were given for cycles two to four.RESULTS The dosing algorithm proposes MTX dose adaptations ranging from +75% in patients with MTX C24 < 0.5 µmol l−1 up to −35% in patients with MTX C24 > 12 µmol l−1. The proposed dosing algorithm resulted in a marked improvement of the proportion of patients within the AUCMTX target between 1000 and 1100 µmol l−1 h (11% with standard MTX dose, 35% with the adjusted dose) and a marked reduction of the interindividual variability of MTX exposure.CONCLUSIONS A simple and practical dosing algorithm for HDMTX has been developed based on MTX 24 h plasma concentrations, and its potential efficacy in improving the proportion of patients within a prespecified target AUCMTX and reducing the interindividual variability of MTX exposure has been shown by data simulations. The clinical benefit of this dosing algorithm should be assessed in patients with primary central nervous system lymphoma (PCNSL).
CYP2C8 but not CYP3A4 is important in the pharmacokinetics of montelukast
Authors: Karonen Tiina , Neuvonen Pertti J. , Backman Janne T. 
Published: August 2011

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT• The elimination of montelukast occurs mainly via metabolism and, according to its product information, CYP3A4 and 2C9 are the main metabolizing enzymes in vitro.• Recent studies, however, suggest that CYP2C8 may have a role in the metabolism of montelukast.WHAT THIS STUDY ADDS• The CYP3A4 inhibitor itraconazole markedly reduces the formation of a minor metabolite of montelukast, but has no significant effect on the total elimination of montelukast.• Montelukast is predominantly metabolized by CYP2C8, and can thus be used as a sensitive CYP2C8 probe drug.AIM According to product information, montelukast is extensively metabolized by CYP3A4 and CYP2C9. However, CYP2C8 was also recently found to be involved. Our aim was to study the effects of selective CYP2C8 and CYP3A4 inhibitors on the pharmacokinetics of montelukast.METHODS In a randomized crossover study, 11 healthy subjects ingested gemfibrozil 600 mg, itraconazole 100 mg (first dose 200 mg) or both, or placebo twice daily for 5 days, and on day 3, 10 mg montelukast. Plasma concentrations of montelukast, gemfibrozil, itraconazole and their metabolites were measured up to 72 h.RESULTS The CYP2C8 inhibitor gemfibrozil increased the AUC(0,∞) of montelukast 4.3‐fold and its t1/2 2.1‐fold (P < 0.001). Gemfibrozil impaired the formation of the montelukast primary metabolite M6, reduced the AUC and Cmax of the secondary (major) metabolite M4 by more than 90% (P < 0.05) and increased those of M5a and M5b (P < 0.05). The CYP3A4 inhibitor itraconazole had no significant effect on the pharmacokinetic variables of montelukast or its M6 and M4 metabolites, but markedly reduced the AUC and Cmax of M5a and M5b (P < 0.05). The effects of the gemfibrozil‐itraconazole combination on the pharmacokinetics of montelukast did not differ from those of gemfibrozil alone.CONCLUSIONS CYP2C8 is the dominant enzyme in the biotransformation of montelukast in humans, accounting for about 80% of its metabolism. CYP3A4 only mediates the formation of the minor metabolite M5a/b, and is not important in the elimination of montelukast. Montelukast may serve as a safe and useful CYP2C8 probe drug.
Erythrocyte‐associated apolipoprotein B and its relationship with clinical and subclinical atherosclerosis
Authors: Bovenberg Sarah A. , Klop Boudewijn , Alipour Arash , Martinez‐Hervas Sergio , Westzaan Andrew , van de Geijn Gert‐Jan M. , Janssen Hans W. J. , Njo Tjin , Birnie Erwin , van Mechelen Rob , Rietveld Arie P. , Elte Jan Willem F. , Castro Cabezas Manuel 
Published: August 2011

Eur J Clin Invest 2012; 42 (4): 365–370AbstractBackground  Apolipoprotein (apo) B‐containing lipoproteins are closely linked to atherogenesis. These lipoproteins are transported in plasma and are also associated with blood leucocytes. Our aim was to investigate whether apoB‐containing lipoproteins are also present on the surface of erythrocytes and investigate the relationship with the presence of atherosclerosis in a cross‐sectional study.Materials and methods  Erythrocyte‐bound apoB (ery‐apoB) was measured by flowcytometry in subjects with (CAD+) and without coronary artery disease (CAD−), based on coronary angiography or on a history of cardiovascular disease. Intima media thickness (IMT) measurements were carried out using B‐mode ultrasound. The relationship between ery‐apoB and clinical and subclinical atherosclerosis was evaluated with binary logistic regression.Results  A total of 166 subjects were included (40 CAD+ and 126 CAD−). ApoB was detected on freshly isolated erythrocytes (range: 0·1–5·5 au; mean ± SEM 0·86 ± 0·09 au) in all but nine subjects (four CAD+ and five CAD−). Ery‐apoB was lower in CAD+ (0·62 ± 0·09 au) compared to CAD− (1·18 ± 0·10 au; P < 0·001). Higher ery‐apoB was associated with a lower risk of CAD (adjusted OR: 0·003 (95% CI: 0·001–0·08; P < 0·001), but the protective effect was diminished with increasing age (adjusted OR: 1·10 (95% CI: 1·04–1·16; P < 0·001). IMT was increased in CAD+ subjects (0·77 ± 0·13 mm) compared to CAD− (0·57 ± 0·14 mm; P < 0·001). A significant negative association was found between ery‐apoB and IMT (β = −0·214: 95% CI −0·284 to −0·145; P < 0·001). There was no association between ery‐apoB and plasma apoB (Pearson’s r = −0·45; P = 0·57).Conclusions  Human erythrocytes carry apoB‐containing lipoproteins. Subjects with atherosclerosis have lower ery‐apoB. High ery‐apoB may be protective against atherosclerosis and may reflect an alternative blood cell–mediated lipoprotein transport system in the circulation, in which these lipoproteins less likely interact with the endothelium.
Nutrients exert a stronger control than climate on recent diatom communities in Esthwaite Water: evidence from monitoring and palaeolimnological records
Authors: DONG XUHUI , BENNION HELEN , MABERLY STEPHEN C. , SAYER CARL D. , SIMPSON GAVIN L. , BATTARBEE RICHARD W. 
Published: August 2011

Summary1. A long‐term monitoring programme on phytoplankton and physicochemical characteristics of Esthwaite Water (England) that started in 1945 provides a rare opportunity to understand the effects of climate and nutrients on a lake ecosystem.2. Monitoring records show that the lake experienced nutrient enrichment from the early 1970s, particularly after 1975, associated with inputs from a local sewage treatment plant, resulting in marked increases in concentration of soluble reactive phosphorus (SRP). Climatic variables, such as air temperature (AirT) and rainfall, exhibit high variability with increasing trends after 1975.3. Diatom analyses of an integrated 210Pb‐dated lake sediment core from Esthwaite Water, covering the period from 1945 to 2004, showed that fossil diatoms exhibited distinct compositional change in response to nutrient enrichment.4. Redundancy analysis (RDA) based on diatom and environmental data sets over the past 60 years showed that the most important variables explaining diatom species composition were winter concentrations of SRP, followed by AirT, independently explaining 22% and 8% of the diatom variance, respectively.5. Additive models showed that winter SRP was the most important factor controlling the diatom assemblages for the whole monitoring period. AirT had little effect on the diatom assemblages when nutrient levels were low prior to 1975. With the increase in nutrient availability during the eutrophication phase after 1975, climate became more important in regulating the diatom community, although SRP was still the major controlling factor.6. The relative effects of climate and nutrients on diatom communities vary depending on the timescale. RDA and additive model revealed that climate contributed little to diatom dynamics at an annual or decadal scale.7. The combination of monitoring and palaeolimnological records employed here offers the opportunity to explore how nutrients and climate have affected a lake ecosystem over a range of timescales. This dual approach can potentially be extended to much longer timescales (e.g. centuries), where long‐term, reliable observational records exist.