bluuebunny/crossref_metadata_2025_split huggingface dataset:
Discussion Group Composition and Deliberation Experience
Authors: Sumaktoyo Nathanael Gratias , Nickerson David W. , Keane Michael J. 
Published: January 2017

AbstractIn order to encouragee broad participation in deliberative forums, it is important to understand how people from politically less powerful groups perceive the deliberative experience and how discussion group composition affects their experiences. Using data from 27 deliberative polls from 2004, we examine how four individual characteristics (sex, age, race, and education) and randomly assigned small group composition predict participants’ attitudes about the deliberative experience. We find evidence that women, young people, non-whites, and those without college degree generally evaluate the experience positively, but find no evidence for the argument that including more people from these groups would lead to more positive deliberation experience for participants from the groups. That is, there is no interaction between minority status and group composition in predicting participants’ evaluation of the deliberation process.
Direct visualization of hydrogen absorption dynamics in individual palladium nanoparticles
Authors: Narayan Tarun C. , Hayee Fariah , Baldi Andrea , Leen Koh Ai , Sinclair Robert , Dionne Jennifer A. 
Published: January 2017

AbstractMany energy storage materials undergo large volume changes during charging and discharging. The resulting stresses often lead to defect formation in the bulk, but less so in nanosized systems. Here, we capture in real time the mechanism of one such transformation—the hydrogenation of single-crystalline palladium nanocubes from 15 to 80 nm—to better understand the reason for this durability. First, using environmental scanning transmission electron microscopy, we monitor the hydrogen absorption process in real time with 3 nm resolution. Then, using dark-field imaging, we structurally examine the reaction intermediates with 1 nm resolution. The reaction proceeds through nucleation and growth of the new phase in corners of the nanocubes. As the hydrogenated phase propagates across the particles, portions of the lattice misorient by 1.5%, diminishing crystal quality. Once transformed, all the particles explored return to a pristine state. The nanoparticles’ ability to remove crystallographic imperfections renders them more durable than their bulk counterparts.
Context-dependent role for chromatin remodeling component PBRM1/BAF180 in clear cell renal cell carcinoma
Authors: Murakami A , Wang L , Kalhorn S , Schraml P , Rathmell W K , Tan A C , Nemenoff R , Stenmark K , Jiang B-H , Reyland M E , Heasley L , Hu C-J 
Published: January 2017

AbstractA subset of clear cell renal cell carcinoma (ccRCC) tumors exhibit a HIF1A gene mutation, yielding two ccRCC tumor types, H1H2 type expressing both HIF1α and HIF2α, and H2 type expressing HIF2α, but not functional HIF1α protein. However, it is unclear how the H1H2 type ccRCC tumors escape HIF1’s tumor-suppressive activity. The polybromo-1 (PBRM1) gene coding for the BAF180 protein, a component of the SWItch/Sucrose Non-Fermentable (SWI/SNF) chromatin remodeling complex, is inactivated in 40% ccRCCs, the function and mechanism of BAF180 mutation is unknown. Our previous study indicates that BAF180-containing SWI/SNF chromatin remodeling complex is a co-activator for transcription factor HIF to induce HIF target genes. Thus, our questions are if BAF180 is involved in HIF-mediated hypoxia response and if PBRM1/BAF180 mutation has any association with the HIF1A retention in H1H2 type ccRCC. We report here that BAF180 is mutated in H1H2 ccRCC cell lines and tumors, and BAF180 re-expression in H1H2 ccRCC cell lines reduced cell proliferation/survival, indicating that BAF180 has tumor-suppressive role in these cells. However, BAF180 is expressed in HIF1-deficient H2 ccRCC cell lines and tumors, and BAF180 knockdown in H2 type ccRCC cell lines reduced cell proliferation/survival, indicating that BAF180 has tumor-promoting activity in these cells. In addition, our data show that BAF180 functions as co-activator for HIF1- and HIF2-mediated transcriptional response, and BAF180’s tumor-suppressive and -promoting activity in ccRCC cell lines depends on co-expression of HIF1 and HIF2, respectively. Thus, our studies reveal that BAF180 function in ccRCC is context dependent, and that mutation of PBRM1/BAF180 serves as an alternative strategy for ccRCC tumors to reduce HIF1 tumor-suppressive activity in H1H2 ccRCC tumors. Our studies define distinct functional subgroups of ccRCCs based on expression of BAF180, and suggest that BAF180 inhibition may be a novel therapeutic target for patients with H2, but not H1H2, ccRCC tumors.
Stable isotopes in the atmospheric marine boundary layer water vapour over the Atlantic Ocean, 2012–2015
Authors: Benetti Marion , Steen-Larsen Hans Christian , Reverdin Gilles , Sveinbjörnsdóttir Árný Erla , Aloisi Giovanni , Berkelhammer Max B. , Bourlès Bernard , Bourras Denis , de Coetlogon Gaëlle , Cosgrove Ann , Faber Anne-Katrine , Grelet Jacques , Hansen Steffen Bo , Johnson Rod , Legoff Hervé , Martin Nicolas , Peters Andrew J. , Popp Trevor James , Reynaud Thierry , Winther Malte 
Published: January 2017

AbstractThe water vapour isotopic composition (1H216O, H218O and 1H2H16O) of the Atlantic marine boundary layer has been measured from 5 research vessels between 2012 and 2015. Using laser spectroscopy analysers, measurements have been carried out continuously on samples collected 10–20 meter above sea level. All the datasets have been carefully calibrated against the international VSMOW-SLAP scale following the same protocol to build a homogeneous dataset covering the Atlantic Ocean between 4°S to 63°N. In addition, standard meteorological variables have been measured continuously, including sea surface temperatures using calibrated Thermo-Salinograph for most cruises. All calibrated observations are provided with 15-minute resolution. We also provide 6-hourly data to allow easier comparisons with simulations from the isotope-enabled Global Circulation Models. In addition, backwards trajectories from the HYSPLIT model are supplied every 6-hours for the position of our measurements.
A systematic review and meta-analysis of seroprevalence surveys of ebolavirus infection
Authors: Bower Hilary , Glynn Judith R. 
Published: January 2017

AbstractAsymptomatic ebolavirus infection could greatly influence transmission dynamics, but there is little consensus on how frequently it occurs or even if it exists. This paper summarises the available evidence on seroprevalence of Ebola, Sudan and Bundibugyo virus IgG in people without known ebolavirus disease. Through systematic review, we identified 51 studies with seroprevalence results in sera collected from 1961 to 2016. We tabulated findings by study population, contact, assay, antigen and positivity threshold used, and present seroprevalence point estimates and 95% confidence intervals. We classified sampled populations in three groups: those with household or known case-contact; those living in outbreak or epidemic areas but without reported case-contact; and those living in areas with no recorded cases of ebolavirus disease. We performed meta-analysis only in the known case-contact group since this is the only group with comparable exposures between studies. Eight contact studies fitted our inclusion criteria, giving an overall estimate of seroprevalence in contacts with no reported symptoms of 3.3% (95% CI 2.4–4.4, P<0.001), but with substantial heterogeneity.
Protein crystal nucleation in pores
Authors: Nanev Christo N. , Saridakis Emmanuel , Chayen Naomi E. 
Published: January 2017

AbstractThe most powerful method for protein structure determination is X-ray crystallography which relies on the availability of high quality crystals. Obtaining protein crystals is a major bottleneck, and inducing their nucleation is of crucial importance in this field. An effective method to form crystals is to introduce nucleation-inducing heterologous materials into the crystallization solution. Porous materials are exceptionally effective at inducing nucleation. It is shown here that a combined diffusion-adsorption effect can increase protein concentration inside pores, which enables crystal nucleation even under conditions where heterogeneous nucleation on flat surfaces is absent. Provided the pore is sufficiently narrow, protein molecules approach its walls and adsorb more frequently than they can escape. The decrease in the nucleation energy barrier is calculated, exhibiting its quantitative dependence on the confinement space and the energy of interaction with the pore walls. These results provide a detailed explanation of the effectiveness of porous materials for nucleation of protein crystals, and will be useful for optimal design of such materials.
Novel strain properties distinguishing sporadic prion diseases sharing prion protein genotype and prion type
Authors: Cracco Laura , Notari Silvio , Cali Ignazio , Sy Man-Sun , Chen Shu G. , Cohen Mark L. , Ghetti Bernardino , Appleby Brian S. , Zou Wen-Quan , Caughey Byron , Safar Jiri G. , Gambetti Pierluigi 
Published: January 2017

AbstractIn most human sporadic prion diseases the phenotype is consistently associated with specific pairings of the genotype at codon 129 of the prion protein gene and conformational properties of the scrapie PrP (PrPSc) grossly identified types 1 and 2. This association suggests that the 129 genotype favours the selection of a distinct strain that in turn determines the phenotype. However, this mechanism cannot play a role in the phenotype determination of sporadic fatal insomnia (sFI) and a subtype of sporadic Creutzfeldt-Jakob disease (sCJD) identified as sCJDMM2, which share 129 MM genotype and PrPSc type 2 but are associated with quite distinct phenotypes. Our detailed comparative study of the PrPSc conformers has revealed major differences between the two diseases, which preferentially involve the PrPSc component that is sensitive to digestion with proteases (senPrPSc) and to a lesser extent the resistant component (resPrPSc). We conclude that these variations are consistent with two distinct strains in sFI and sCJDMM2, and that the rarer sFI is the result of a variant strain selection pathway that might be favoured by a different brain site of initial PrPSc formation in the two diseases.
The autofluorescence characteristics of bacterial intracellular and extracellular substances during the operation of anammox reactor
Authors: Hou Xiaolin , Liu Sitong , Feng Ying 
Published: January 2017

AbstractAnammox is a cost-effective process to treat nitrogenous wastewater. In this work, excitation–emission matrix (EEM) fluorescence spectroscopy was used to characterize the intracellular and extracellular substances of anammox sludge during reactor operation of 276 days. Four main fluorophores were identified from the intracellular substances. Two main protein-like fluorophores were identified from the extracellular substances. Correlation analysis revealed that intracellular 420 peak and humic-like peak had strong correlation with nitrogen removal rate. The two intracellular protein-like peaks had high correlation with MLVSS and MLVSS growth rate. Correlation analysis between different fluorophores discovered that the two peaks in each of these three groups—two intracellular protein-like peaks, two humic acid-like peaks and the two extracellular protein-like peaks had strong intercorrelation, which gave evidence of their homology. A specific method for fluorescence monitoring of anammox reactor were put forward, which included typical fluorescence indexes and their possible values for different operation phases.
Formate simultaneously reduces oxidase activity and enhances respiration in Campylobacter jejuni
Authors: Kassem Issmat I. , Candelero-Rueda Rosario A. , Esseili Kawthar A. , Rajashekara Gireesh 
Published: January 2017

AbstractThe foodborne microaerophilic pathogen, Campylobacter jejuni, possesses a periplasmic formate dehydrogenase and two terminal oxidases, which serve to metabolize formate and facilitate the use of oxygen as a terminal electron acceptor, respectively. Formate, a primary energy source for C. jejuni, inhibits oxidase activity in other bacteria. Here, we hypothesized that formate might affect both energy metabolism and microaerobic survival in C. jejuni. Subsequently, we showed that C. jejuni 81–176 (wildtype) exhibited enhanced chemoattraction to and respiration of formate in comparison to other organic acids. Formate also significantly increased C. jejuni’s growth, motility, and biofilm formation under microaerobic (5% O2) conditions. However, formate reduced oxidase activity under microaerobic conditions as well as aerotolerance and biofilm formation under ambient oxygen conditions. The expression of genes encoding the ribonucleotide reductase (RNR) and proteins that facilitate the use of alternative electron acceptors generally increased in the presence of formate. Taken together, formate might play a role in optimizing C. jejuni’s adaptation to the oxygen-limited gastrointestinal tract of the host. By affecting oxidase activity, formate possibly facilitates shuttling electrons to alternative acceptors, while likely conserving limited oxygen concentrations for other essential functions such as DNA synthesis via RNR which is required for C. jejuni’s growth.
Cr incorporated phase transformation in Y2O3 under ion irradiation
Authors: Li N. , Yadav S. K. , Xu Y. , Aguiar J. A. , Baldwin J. K. , Wang Y. Q. , Luo H. M. , Misra A. , Uberuaga B. P. 
Published: January 2017

AbstractUnder irradiation, chemical species can redistribute in ways not expected from equilibrium behavior. In oxide-dispersed ferritic alloys, the phenomenon of irradiation-induced Cr redistribution at the metal/oxide interfaces has drawn recent attention. Here, the thermal and irradiation stability of the FeCr/Y2O3 interface has been systematically studied. Trilayer thin films of 90 nm Fe - 20 at.% Cr (1st layer)/100 nm Y2O3 (2nd layer)/135 nm Fe - 20 at.% Cr (3rd layer) were deposited on MgO substrates at 500 °C. After irradiation, Cr diffuses towards and enriches the FeCr/Y2O3 interface. Further, correlated with Cr redistributed into the oxide, an amorphous layer is generated at the interface. In the Y2O3 layer, the original cubic phase is observed to transform to the monoclinic phase after irradiation. Meanwhile, nanosized voids, with relatively larger size at interfaces, are also observed in the oxide layer. First-principles calculations reveal that Cr substitution of Y interstitials in Y2O3 containing excess Y interstitials is favored and the irradiation-induced monoclinic phase enhances this process. Our findings provide new insights that may aid in the development of irradiation resistant oxide-dispersed ferritic alloys.
Mechanisms of intrinsic resistance and acquired susceptibility of Pseudomonas aeruginosa isolated from cystic fibrosis patients to temocillin, a revived antibiotic
Authors: Chalhoub Hussein , Pletzer Daniel , Weingart Helge , Braun Yvonne , Tunney Michael M. , Elborn J. Stuart , Rodriguez-Villalobos Hector , Plésiat Patrick , Kahl Barbara C. , Denis Olivier , Winterhalter Mathias , Tulkens Paul M. , Van Bambeke Françoise 
Published: January 2017

AbstractThe β-lactam antibiotic temocillin (6-α-methoxy-ticarcillin) shows stability to most extended spectrum β-lactamases, but is considered inactive against Pseudomonas aeruginosa. Mutations in the MexAB-OprM efflux system, naturally occurring in cystic fibrosis (CF) isolates, have been previously shown to reverse this intrinsic resistance. In the present study, we measured temocillin activity in a large collection (n = 333) of P. aeruginosa CF isolates. 29% of the isolates had MICs ≤ 16 mg/L (proposed clinical breakpoint for temocillin). Mutations were observed in mexA or mexB in isolates for which temocillin MIC was ≤512 mg/L (nucleotide insertions or deletions, premature termination, tandem repeat, nonstop, and missense mutations). A correlation was observed between temocillin MICs and efflux rate of N-phenyl-1-naphthylamine (MexAB-OprM fluorescent substrate) and extracellular exopolysaccharide abundance (contributing to a mucoid phenotype). OpdK or OpdF anion-specific porins expression decreased temocillin MIC by ~1 two-fold dilution only. Contrarily to the common assumption that temocillin is inactive on P. aeruginosa, we show here clinically-exploitable MICs on a non-negligible proportion of CF isolates, explained by a wide diversity of mutations in mexA and/or mexB. In a broader context, this work contributes to increase our understanding of MexAB-OprM functionality and help delineating how antibiotics interact with MexA and MexB.
A disrupted transsulphuration pathway results in accumulation of redox metabolites and induction of gametocytogenesis in malaria
Authors: Beri Divya , Balan Balu , Chaubey Shweta , Subramaniam Suraj , Surendra Bachu , Tatu Utpal 
Published: January 2017

AbstractIntra-erythrocytic growth of malaria parasite is known to induce redox stress. In addition to haem degradation which generates reactive oxygen species (ROS), the parasite is also thought to efflux redox active homocysteine. To understand the basis underlying accumulation of homocysteine, we have examined the transsulphuration (TS) pathway in the parasite, which is known to convert homocysteine to cysteine in higher eukaryotes. Our bioinformatic analysis revealed absence of key enzymes in the biosynthesis of cysteine namely cystathionine-β-synthase and cystathionine-γ-lyase in the parasite. Using mass spectrometry, we confirmed the absence of cystathionine, which is formed by enzymatic conversion of homocysteine thereby confirming truncation of TS pathway. We also quantitated levels of glutathione and homocysteine in infected erythrocytes and its spent medium. Our results showed increase in levels of these metabolites intracellularly and in culture supernatants. Our results provide a mechanistic basis for the long-known occurrence of hyperhomocysteinemia in malaria. Most importantly we find that homocysteine induces the transcription factor implicated in gametocytogenesis namely AP2-G and consequently triggers sexual stage conversion. We confirmed this observation both in vitro using Plasmodium falciparum cultures, and in vivo in the mouse model of malaria. Our study implicates homocysteine as a potential physiological trigger of gametocytogenesis.
ATP Binding Cassette Transporter ABCA7 Regulates NKT Cell Development and Function by Controlling CD1d Expression and Lipid Raft Content
Authors: Nowyhed Heba N. , Chandra Shilpi , Kiosses William , Marcovecchio Paola , Andary Farah , Zhao Meng , Fitzgerald Michael L. , Kronenberg Mitchell , Hedrick Catherine C. 
Published: January 2017

AbstractABCA7 is an ABC transporter expressed on the plasma membrane, and actively exports phospholipid complexes from the cytoplasmic to the exocytoplasmic leaflet of membranes. Invariant NKT (iNKT) cells are a subpopulation of T lymphocytes that recognize glycolipid antigens in the context of CD1d-mediated antigen presentation. In this study, we demonstrate that ABCA7 regulates the development of NKT cells in a cell-extrinsic manner. We found that inAbca7−/−mice there is reduced expression of CD1d accompanied by an alteration in lipid raft content on the plasma membrane of thymocytes and antigen presenting cells. Together, these alterations caused by absence of ABCA7 negatively affect NKT cell development and function.
Platelet, monocyte and neutrophil activation and glucose tolerance in South African Mixed Ancestry individuals
Authors: Davison Glenda M. , Nkambule Bongani B. , Mkandla Zibusiso , Hon Gloudina M. , Kengne Andre P. , Erasmus Rajiv T. , Matsha Tandi E. 
Published: January 2017

AbstractPlatelet activation has been described in patients with chronic inflammation, however in type 2 diabetes mellitus it remains controversial. We compared levels of platelet leucocyte aggregates, monocyte and granulocyte activation across glucose tolerance statuses in mixed ancestry South Africans. Individuals (206) were recruited from Bellville-South, Cape Town, and included 66% with normal glucose tolerance, 18.7% pre-diabetes, 8.7% screen-detected diabetes and 6.3% known diabetes. Monocyte and neutrophil activation were measured by calculating the percentage of cells expressing CD142 and CD69 while platelet monocyte aggregates were defined as CD14++ CD42b+ events and platelet neutrophil aggregates as CD16++ CD42b+ events. The percentage of monocytes and neutrophils expressing CD69 and CD142 was significantly higher in known diabetes and prediabetes, but, lowest in screen-detected diabetes (both p ≤ 0.016). The pattern was similar for platelet monocyte and neutrophil aggregates (both p ≤ 0.003). In robust linear regressions adjusted for age and gender, known diabetes was significantly and positively associated with the percentage of monocytes expressing CD69 [beta 11.06 (p = 0.016)] and CD42b (PMAs) [19.51 (0.003)] as well as the percentage of neutrophils expressing CD69 [14.19 (<0.0001)] and CD42b [17.7 (0.001)]. We conclude that monitoring platelet activation in diagnosed diabetic patients may have a role in the management and risk stratification.
Shifts in the fluorescence lifetime of EGFP during bacterial phagocytosis measured by phase-sensitive flow cytometry
Authors: Li Wenyan , Houston Kevin D. , Houston Jessica P. 
Published: January 2017

AbstractPhase-sensitive flow cytometry (PSFC) is a technique in which fluorescence excited state decay times are measured as fluorescently labeled cells rapidly transit a finely focused, frequency-modulated laser beam. With PSFC the fluorescence lifetime is taken as a cytometric parameter to differentiate intracellular events that are challenging to distinguish with standard flow cytometry. For example PSFC can report changes in protein conformation, expression, interactions, and movement, as well as differences in intracellular microenvironments. This contribution focuses on the latter case by taking PSFC measurements of macrophage cells when inoculated with enhanced green fluorescent protein (EGFP)-expressingE. coli. During progressive internalization of EGFP-E. coli, fluorescence lifetimes were acquired and compared to control groups. It was hypothesized that fluorescence lifetimes would correlate well with phagocytosis because phagosomes become acidified and the average fluorescence lifetime of EGFP is known to be affected by pH. We confirmed that average EGFP lifetimes consistently decreased (3 to 2 ns) with inoculation time. The broad significance of this work is the demonstration of how high-throughput fluorescence lifetime measurements correlate well to changes that are not easily tracked by intensity-only cytometry, which is affected by heterogeneous protein expression, cell-to-cell differences in phagosome formation, and number of bacterium engulfed.