bluuebunny/crossref_metadata_2025_split huggingface dataset:
Consumption of selenium‐enriched broccoli increases cytokine production in human peripheral blood mononuclear cells stimulated ex vivo, a preliminary human intervention study
Authors: Bentley‐Hewitt Kerry L. , Chen Ronan K.‐Y. , Lill Ross E. , Hedderley Duncan I. , Herath Thanuja D. , Matich Adam J. , McKenzie Marian J. 
Published: August 2014

ScopeSelenium (Se) is a micronutrient essential for human health, including immune function. Previous research indicates that Se supplementation may cause a shift from T helper (Th)1‐ to Th2‐type immune responses. We aim to test the potential health promoting effects of Se‐enriched broccoli.Methods and resultsIn a human trial, 18 participants consumed control broccoli daily for 3 days. After a 3‐day wash‐out period, the participants were provided with Se‐enriched broccoli containing 200 μg of Se per serving for 3 days. Plasma and peripheral blood mononuclear cell (PBMC) samples were collected at the start and end of each broccoli feeding period for analysis of total Se and measurement of cytokine production from PBMC stimulated with antigens ex vivo. Plasma Se content remained consistent throughout the control broccoli feeding period and the baseline of the Se‐enriched broccoli period (1.22 μmol/L) and then significantly increased following 3 days of Se‐enriched broccoli feeding. Interleukin (IL‐2, IL‐4, IL‐5, IL‐13, and IL‐22) production from PBMC significantly increased after 3 days of Se‐enriched broccoli feeding compared with baseline.ConclusionThis study indicates that consumption of Se‐enriched broccoli may increase immune responses toward a range of immune challenges.
Virtual topography: A fictitious domain approach for analyzing free‐surface irregularities in large‐scale earthquake ground motion simulation
Authors: Restrepo Doriam , Bielak Jacobo 
Published: August 2014

SUMMARYThis paper presents a numerical scheme based on a fictitious domain framework for the numerical modeling of earthquake‐induced ground motion in the presence of realistic surface topography of the Earth's crust. We show that by adopting a non‐conforming octree‐based meshing approach associated with a virtual representation of the surficial irregularity, we can obtain accurate representations of ground motion. From the computational point of view, our methodology proves to be also efficient, and more importantly, it allows us to preserve the salient features of multi‐resolution cubic‐shaped finite elements for wave propagation applications. We implemented the non‐conforming meshing scheme for the treatment of realistic topographies into Hercules, the octree‐based finite‐element earthquake simulator developed by the Quake Group at Carnegie Mellon University. We tested the benefits of the strategy by benchmarking its results against reference examples, and by means of numerical error estimate analyses. Our qualitative and quantitative comparisons showed a close agreement between our numerical results and the reference results, and also, that the order of convergence of the displacement field is preserved in the presence of surface topography. Moreover, this performance was obtained by using the same mesh refinement techniques with cubic elements as in traditional flat free‐surface simulations. Copyright © 2014 John Wiley & Sons, Ltd.
Effects of intensive lifestyle intervention and gastric bypass on aortic stiffness: A 1‐year nonrandomized clinical study
Authors: Gjevestad Espen , Hjelmesæth Jøran , Sandbu Rune , Nordstrand Njord 
Published: August 2014

ObjectiveTo compare the long‐term effects of Roux‐en‐Y gastric bypass (GBS) and intensive lifestyle intervention (ILI) on aortic stiffness.MethodsNonrandomized clinical trial. Aortic stiffness was assessed by carotid‐femoral pulse wave velocity (cfPWV) using high‐fidelity applanation tonometry.ResultsA total of 159 treatment‐seeking morbidly obese patients were included, 82 (54 females) in the GBS‐group and 77 (48 females) in the ILI‐group. Participants in the GBS‐group were younger (42.0 ± 9.9 vs. 46.4 ± 10.5 years), heavier (BMI 45.7 ± 5.3 vs. 42.0 ± 4.9 kg/m2), and had lower systolic pressure (137 ± 19 vs. 145 ± 18 mm Hg) and pulse pressure (57 ± 16 vs. 65 ± 17 mm Hg), all P ≤ 0.006. Mean (SD) cfPWV at baseline was 8.6 ± 1.7 m/s in the GBS‐group and 8.6 ± 1.9 m/s in the ILI‐group, P = 0.959. At follow‐up, mean (95% CI) weight loss was larger in the GBS‐group than in the ILI‐group −43.3 (−46.0 to −40.7) vs. −12.1 (−14.6 to −9.6) kg, P < 0.001. The mean change in cfPWV was −0.02 (−0.31 to 0.27) m/s in the GBS‐group and 0.03 (−0.28 to 0.33) m/s in the ILI‐group, both P ≥ 0.412; adjusted between‐group difference (ANCOVA) 0.05 (−0.40 to 0.49) m/s, P = 0.836. The adjusted regression analysis showed that weight loss was associated with increased cfPWV in the GBS‐group.ConclusionsGBS and ILI had no significant long‐term effects on aortic stiffness in treatment‐seeking morbidly obese individuals.
Differential PI3K signal transduction in obesity‐associated cardiac hypertrophy and response to ischemia
Authors: Unsöld Bernhard , Bremen Eva , Didié Michael , Hasenfuss Gerd , Schäfer Katrin 
Published: August 2014

ObjectiveElevated insulin and inflammatory cytokine levels in obesity may chronically activate signaling pathways regulating cardiac growth and contractility. Our aim was to examine the effect of obesity on cardiac PI3K isoform and Akt activation during left ventricular (LV) hypertrophy and heart failure.MethodsWild‐type mice were fed normal chow or high‐fat diet (HFD) for 2, 4, or 6 months. A subset of mice was subjected to chronic myocardial ischemia (MI).ResultsEchocardiography revealed a progressive increase in LV mass, wall thickness, and diameters in obese mice. Systolic pump function was not impaired. Increased cardiac levels of PI3Kγ, phosphorylated Akt, GSK3β, and Epac were observed after HFD for 2 months but gradually declined and were normal or reduced after 6 months, paralleled by elevated PP2A and SOCS3 levels. MI resulted in heart failure, independent of obesity, but compensatory LV hypertrophy was absent in obese mice. Histochemical analyses revealed similar increases in cardiac fibrosis, inflammation, apoptosis, and angiogenesis in lean and obese mice.ConclusionsOur findings suggest that activation of Akt initially contributes to cardiac hypertrophy and that chronic metabolic and inflammatory stimulation and overexpression of inhibitory mediators decrease PI3Kγ‐mediated Akt signaling and blunt compensatory hypertrophy after MI.
Stabilization and functionalization of single‐walled carbon nanotubes with polyvinylpyrrolidone copolymers for applications in aqueous media
Authors: Popp Brian V. , Miles Dillon H. , Smith Jake A. , Fong Irene M. , Pasquali Matteo , Ball Zachary T. 
Published: August 2014

ABSTRACTIn spite of their useful electronic and mechanical properties, the utility of single‐walled carbon nanotubes (SWNT) is limited by their inherent insolubility in aqueous environments and the difficulty in functionalizing the material while retaining opto‐electric properties. In this article, the synthesis of polyvinylpyrrolidone (PVP) copolymers for wrapping SWNTs is described. Studies include the effect of polymer composition and charge on SWNT stability in aqueous solution and the variation of the stability of wrapped SWNTs during high‐dilution conditions using dialysis studies. Finally, the PVP‐copolymer strategy is used to create polymer wrappers with functional handles for the incorporation of useful chemical functionality. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 337–343
Design of high‐χ block copolymers for lithography
Authors: Durand William J. , Blachut Gregory , Maher Michael J. , Sirard Stephen , Tein Summer , Carlson Matthew C. , Asano Yusuke , Zhou Sunshine X. , Lane Austin P. , Bates Christopher M. , Ellison Christopher J. , Willson C. Grant 
Published: August 2014

ABSTRACTThis report describes the design and synthesis of a series of lamella‐forming, silicon‐containing block copolymers (Si‐BCPs) and evaluation of these materials as potential candidates for lithographic applications. The interaction parameter χ of each Si‐BCP is measured by both the mean‐field theory predicted order‐disorder transition and by analysis of X‐ray scattering profiles. The introduction of more‐polar methoxy and less‐polar methylsilyl moieties increases χ to about 2–3 times that of the reference material, poly(styrene‐block−4‐trimethylsilylstyrene). The incremental increases appear to be essentially additive in this family of block copolymers, suggesting that improvements in χ can be predicted from appropriate monomer choice. Perpendicularly oriented thin‐films of the ordered Si‐BCPs generated by thermally annealing between two “neutral” polymeric surfaces and developed by etching on commercial RIE equipment show excellent image fidelity. These images demonstrate the excellent etch contrast of the Si‐BCPs and document improvements in pattern fidelity that are realized with more strongly segregated BCPs. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 344–352
Iron inhibits Escherichia coli topoisomerase I activity by targeting the first two zinc‐binding sites in the C‐terminal domain
Authors: Wang Wu , Su Xiaolu , Wang Xiaobing , Yang Juanjuan , Zhang Ting , Wang Maofeng , Wan Rugen , Tan Guoqiang , Lu Jianxin 
Published: August 2014

AbstractEscherichia coli DNA topoisomerase I (TopA) contains a 67 kDa N‐terminal catalytic domain and a 30 kDa C‐terminal zinc‐binding region (ZD domain) which has three adjacent tetra‐cysteine zinc‐binding motifs. Previous studies have shown that E. coli TopA can bind both iron and zinc, and that iron binding in TopA results in failure to unwind the negatively supercoiled DNA. Here, we report that each E. coli TopA monomer binds one atom of iron via the first two zinc‐binding motifs in ZD domain and both the first and second zinc‐binding motifs are required for iron binding in TopA. The site‐directed mutagenesis studies further reveal that while the mutation of the third zinc‐binding motif has very little effect on TopA's activity, mutation of the first two zinc‐binding motifs in TopA greatly diminishes the topoisomerase activity in vitro and in vivo, indicating that the first two zinc‐binding motifs in TopA are crucial for its function. The DNA‐binding activity assay and intrinsic tryptophan fluorescence measurements show that iron binding in TopA may decrease the single‐stranded (ss) DNA‐binding activity of ZD domain and also change the protein structure of TopA, which subsequently modulate topoisomerase activity.
High‐resolution crystal structures of the photoreceptor glyceraldehyde 3‐phosphate dehydrogenase (GAPDH) with three and four‐bound NAD molecules
Authors: Baker Bo Y. , Shi Wuxian , Wang Benlian , Palczewski Krzysztof 
Published: August 2014

AbstractGlyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) catalyzes the oxidative phosphorylation of d‐glyceraldehyde 3‐phosphate (G3P) into 1,3‐diphosphoglycerate (BGP) in the presence of the NAD cofactor. GAPDH is an important drug target because of its central role in glycolysis, and nonglycolytic processes such as nuclear RNA transport, DNA replication/repair, membrane fusion and cellular apoptosis. Recent studies found that GAPDH participates in the development of diabetic retinopathy and its progression after the cessation of hyperglycemia. Here, we report two structures for native bovine photoreceptor GAPDH as a homotetramer with differing occupancy by NAD, bGAPDH(NAD)4, and bGAPDH(NAD)3. The bGAPDH(NAD)4 was solved at 1.52 Å, the highest resolution for GAPDH. Structural comparison of the bGAPDH(NAD)4 and bGAPDH(NAD)3 models revealed novel details of conformational changes induced by cofactor binding, including a loop region (residues 54–56). Structure analysis of bGAPDH confirmed the importance of Phe34 in NAD binding, and demonstrated that Phe34 was stabilized in the presence of NAD but displayed greater mobility in its absence. The oxidative state of the active site Cys149 residue is regulated by NAD binding, because this residue was found oxidized in the absence of dinucleotide. The distance between Cys149 and His176 decreased upon NAD binding and Cys149 remained in a reduced state when NAD was bound. These findings provide an important structural step for understanding the mechanism of GAPDH activity in vision and its pathological role in retinopathies.
Understanding the apparent stator‐rotor connections in the rotary ATPase family using coarse‐grained computer modeling
Authors: Richardson Robin A. , Papachristos Konstantinos , Read Daniel J. , Harlen Oliver G. , Harrison Michael , Paci Emanuele , Muench Stephen P. , Harris Sarah A. 
Published: August 2014

ABSTRACTAdvances in structural biology, such as cryo‐electron microscopy (cryo‐EM) have allowed for a number of sophisticated protein complexes to be characterized. However, often only a static snapshot of a protein complex is visualized despite the fact that conformational change is frequently inherent to biological function, as is the case for molecular motors. Computer simulations provide valuable insights into the different conformations available to a particular system that are not accessible using conventional structural techniques. For larger proteins and protein complexes, where a fully atomistic description would be computationally prohibitive, coarse‐grained simulation techniques such as Elastic Network Modeling (ENM) are often employed, whereby each atom or group of atoms is linked by a set of springs whose properties can be customized according to the system of interest. Here we compare ENM with a recently proposed continuum model known as Fluctuating Finite Element Analysis (FFEA), which represents the biomolecule as a viscoelastic solid subject to thermal fluctuations. These two complementary computational techniques are used to answer a critical question in the rotary ATPase family; implicit within these motors is the need for a rotor axle and proton pump to rotate freely of the motor domain and stator structures. However, current single particle cryo‐EM reconstructions have shown an apparent connection between the stators and rotor axle or pump region, hindering rotation. Both modeling approaches show a possible role for this connection and how it would significantly constrain the mobility of the rotary ATPase family. Proteins 2014; 82:3298–3311. © 2014 The Authors. Proteins: Structure, Function, and Bioinformatics Published by Wiley Periodicals, Inc.
TEMPORARY RIVERS: LINKING ECOHYDROLOGY, ECOLOGICAL QUALITY AND RECONCILIATION ECOLOGY
Authors: Arthington A. H. , Bernardo J. M. , Ilhéu M. 
Published: August 2014

ABSTRACTTemporary streams and rivers, also referred to as intermittent, are defined as waterways that cease to flow at some points in space and time along their course. They are shaped by alternating wet and dry periods over annual and inter‐annual cycles, making them one of the most dynamic freshwater ecosystems. These distinctive systems represent a substantial proportion of the total number, length and discharge of the global river network and are expected to become more widespread and face increasing pressures in many regions as a result of human activities and climate change. This collection of papers arose from the Conference on ‘Ecohydrology and Ecological Quality in Temporary Rivers’ held at the University of Evora, Portugal, 12–14 September 2012. The primary objectives of the meeting were to bring together researchers and expertise from a range of temporary ecosystems, from small temporary Mediterranean and Californian streams to intermittent rivers from semi‐arid and arid zones. A common thread through the discussions was the assessment of ecological conditions within these dynamic ecosystems. To undertake a ’condition assessment’ is challenging because of the need to differentiate between biotic responses to anthropogenic pressures and natural variability associated with the hydro‐climatology and disturbance regime typical of these systems, that is, drought, drying and flooding. The management of degraded intermittent streams and rivers presents many new challenges, not least how to reconcile ecological and societal goals for emerging ‘novel’ ecosystems. Reconciliation ecology presents a realistic way of managing novel ecosystems given their value and desirable ecological services to society, rather than trying to restore to an original ecological state that may not be sustainable or economically possible. Copyright © 2014 John Wiley & Sons, Ltd.
A General Approach to Predicting Ecological Responses to Environmental Flows: Making Best Use of the Literature, Expert Knowledge, and Monitoring Data
Authors: Webb J. A. , de Little S. C. , Miller K. A. , Stewardson M. J. , Rutherfurd I. D. , Sharpe A. K. , Patulny L. , Poff N. L. 
Published: August 2014

AbstractAround the world, governments are making huge investments in environmental flows. However, much of the rationale for these releases is based on expert opinion and is thus open to challenge. Empirical studies that relate ecological responses to flow restoration are mostly case studies of limited generality. Radically, different approaches are required to inform the development of general models that will allow us to predict the effects of environmental flows. Here, we describe the modelling framework being used in a major study of environmental flows in the Australian state of Victoria. The framework attempts to make best use of all the information available from the literature, experts, and monitoring data, to inform the development of general quantitative response models. It uses systematic review of the literature to develop evidence‐based conceptual models, formal expert elicitation to provide an initial quantification of model links, and data derived from purpose‐designed monitoring programs over large spatial scales. These elements come together in a Bayesian hierarchical model that quantifies the relationship between flow variation and ecological response and hence can be used to predict ecological responses to flow restoration. We illustrate the framework using the example of terrestrial vegetation encroachment into regulated river channels. Our modelling framework aims to develop general flow‐response models and can immediately be used to demonstrate the ecological return on investment from environmental flow programs. However, the framework also has the potential to be incorporated into planning and decision‐making processes, helping to drive a transformation in evidence‐based practice for environmental flow management. © 2014 The Authors. River Research and Applications published by John Wiley & Sons, Ltd.
Fate, Transport and Effects of Pollutants Originating from Acid Mine Drainage in the Olifants River, South Africa
Authors: Dabrowski J. M. , Dabrowski J. , Hill L. , MacMillan P. , Oberholster P. J. 
Published: August 2014

AbstractConcentrations of pollutants were measured in water, sediment and algal samples collected along a longitudinal gradient from a stretch of the Olifants River, South Africa, that receives acid mine drainage (AMD) from the Klipspruit River. The effects of AMD were determined through macroinvertebrate biotic indices (SASS5) and multivariate analysis of macroinvertebrate communities. The acidic Klipspruit River caused increased concentrations of total Al, Fe and Mn in the Olifants River. Upon mixing of the Klipspruit with that from the alkaline Olifants River, Al and Fe precipitate rapidly, leading to lower concentrations in the dissolved phase and higher concentrations in the suspended phase and in sediment at sites in close proximity to the confluence. Similarly, filamentous algae accumulated high concentrations of Al, Fe and Zn immediately after the confluence. Mn remains in the dissolved phase, and sediment and algal concentrations increase with increasing distance downstream. Metal speciation analysis indicate that Al is rapidly converted from more toxic forms (e.g. Al3+ and Al(OH)2+) to less toxic forms (e.g. Al(OH)3(aq) and Al(OH)4−). In contrast, Mn remains in the soluble Mn2+ form. Macroinvertebrate metrics and community structure showed clear signs of deterioration in water quality in the Olifants River downstream of the point of AMD input. While total TDS concentrations at all sites fall within ranges likely to affect macroinvertebrates, the relative composition of major ions changes as a result of AMD input, which may also account for the observed changes in macroinvertebrate communities. Further downstream, the Wilge River discharges into the Olifants River and significantly improves water quality downstream of the confluence. Future mining and development activities in the Wilge catchment should be carefully managed and monitored so as to ensure sufficient flows of acceptable quality to prevent further deterioration of water quality in the Olifants River and downstream reservoirs. Copyright © 2014 John Wiley & Sons, Ltd.
Life‐History Plasticity of Riparian Annual Plants Adapted to Extreme Variations in Water Level: Mesocosm Experiments
Authors: Song Y. , Ke X. , Liu W. , Davy A. J. , Liu G. 
Published: August 2014

AbstractThe riparian zones of reservoirs associated with regulated rivers in China experience annual fluctuations in water level of up to 30 m that may vary in timing from year to year. Few plant species can tolerate such hydrological perturbation, but short‐lived riparian annuals might be evolutionarily pre‐adapted to such conditions. This study investigated plasticity of life history in four annual species: one typically associated with free‐flowing rivers (Panicum bisulcatum) and three that colonize reservoir margins (Cyperus michelianus, Fimbristylis miliacea and Eclipta prostrata). We found that all four species produced non‐dormant seeds that survived prolonged submergence; germination percentage was independent of the time of exposure by receding waters. Although growth was reduced as a result of shorter growing seasons, all four species completed their life cycles and produced seeds before winter. In addition, P. bisulcatum and C. michelianus allocated biomass to seed production, at the expense of roots and stems, in response to later establishment. All species responded to later establishment with a reduced vegetative growth period before seed production. C. michelianus, F. miliacea and E. prostrate could also delay the onset of flowering time by up to 2 months. P. bisulcatum, a plant that can flower only after exposure to short days, consequently had a fixed flowering time and could accommodate delayed establishment only with a progressively shorter period of vegetative growth. This lower flexibility might explain its absence from reservoir margins. The conceptual framework presented here offers a tool to predict the establishment of vegetation under hydrological disturbance in riparian environments and thereby provides insights into improved restoration practice. Copyright © 2014 John Wiley & Sons, Ltd.
Beyond Fun and Games
Authors: Wood Summer , Jocius Robin 
Published: August 2014

AbstractIt is no secret that technology is ever evolving and impacting the ways in which we engage in society. This reality is also true when considering how young children express knowledge. In this article we discuss the ways in which three iPad applications were used for critical responses to children's literature. We highlight the ways in which two elementary Black male students used these digital tools to respond critically to issues of power and equity presented in the children's literature used in the tutoring program in which they were taking part.