bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New Magnetic Field Activity Proxy for Mars From MAVEN Data
Authors: Mittelholz A. , Johnson C. L. , Morschhauser A. 
Published: June 2018

AbstractThe identification of magnetically quiet or noisy observations is important for data selection in a wide range of studies, including crustal field modeling and investigations of the ionosphere. However this remains a challenge when studying the magnetic field of Mars, as no continuous magnetic activity index is available. Such indices are widely used for studies of Earth's magnetic field, and they are largely based on data from ground observatories. We suggest a martian magnetic activity proxy based on satellite data, from the Mars Atmosphere and Volatile EvolutioN spacecraft (MAVEN). MAVEN has been in orbit since November 2014, providing measurements of the magnetic field that extend those from the Mars Global Surveyor mission. The proxy uses the magnitude of the interplanetary magnetic field upstream of the bow shock and is motivated by the correlation of the interplanetary magnetic field amplitude with the nightside magnetic field at 150‐ to 600‐km altitude, measured on the same MAVEN orbit. We demonstrate the utility of the proxy, by producing a model of the surface crustal field in a previously mapped low‐amplitude region in the vicinity of the InSight landing site. The proposed proxy successfully separates quiet and noisy data and will facilitate MAVEN data selection for higher‐resolution crustal field models. Other applications include data selection for magnetic sounding studies using the InSight magnetometer, or studies of the ionosphere. The deployment of a ground‐based magnetometer by InSight will also allow the refinement of the proxy, using simultaneous satellite and surface magnetic field measurements.
Effect of Dispersive Soil on the Electromagnetic Response of Buried Wires in the UHF Range
Authors: Pantoja John J. , Vega Felix , Román Francisco , Rachidi Farhad 
Published: June 2018

AbstractIn this paper, we analyze the effect of the soil on the induced current in a buried wire excited by an external field in the ultrahigh frequency range. We use an extended version of the Messier model, which provides the electromagnetic (EM) properties of dispersive soils. Based on comparisons of the Messier model and experimental data, it is verified that this model can be used up to a frequency of about 4 GHz for wet soils. A buried straight wire is used for analyzing the soil effect on the EM coupling with an external plane wave impinging from the air. It is shown that the effects of the soil on the EM response of a wire are mainly (i) to modify its electrical length and (ii) to attenuate the incident wave and, as a consequence, the induced current in the wire. The accuracy of the path decomposition method is assessed. It is shown that this method can be used to estimate with reasonable accuracy the behavior of the induced current. Finally, we study the influence of the frequency‐dependence of the soil parameters on the EM coupling to a buried wire. We show that the dispersive nature of the soils affects the spectral content of induced currents in buried wires. Therefore, it can be concluded that the frequency dependence of the soil parameters should not be neglected in EM coupling calculations in the UHF range, especially for low resistivity soils (ρ < 300 Ωm, corresponding to wet soils).
Single-breath-hold photoacoustic computed tomography of the breast
Authors: Lin Li , Hu Peng , Shi Junhui , Appleton Catherine M. , Maslov Konstantin , Li Lei , Zhang Ruiying , Wang Lihong V. 
Published: June 2018

AbstractWe have developed a single-breath-hold photoacoustic computed tomography (SBH-PACT) system to reveal detailed angiographic structures in human breasts. SBH-PACT features a deep penetration depth (4 cm in vivo) with high spatial and temporal resolutions (255 µm in-plane resolution and a 10 Hz 2D frame rate). By scanning the entire breast within a single breath hold (~15 s), a volumetric image can be acquired and subsequently reconstructed utilizing 3D back-projection with negligible breathing-induced motion artifacts. SBH-PACT clearly reveals tumors by observing higher blood vessel densities associated with tumors at high spatial resolution, showing early promise for high sensitivity in radiographically dense breasts. In addition to blood vessel imaging, the high imaging speed enables dynamic studies, such as photoacoustic elastography, which identifies tumors by showing less compliance. We imaged breast cancer patients with breast sizes ranging from B cup to DD cup, and skin pigmentations ranging from light to dark. SBH-PACT identified all the tumors without resorting to ionizing radiation or exogenous contrast, posing no health risks.
Strong lowering of ionization energy of metallic clusters by organic ligands without changing shell filling
Authors: Chauhan Vikas , Reber Arthur C. , Khanna Shiv N. 
Published: June 2018

AbstractAlkali atoms have unusually low ionization energies because their electronic structures have an excess electron beyond that of a filled electronic shell. Quantum states in metallic clusters are grouped into shells similar to those in atoms, and clusters with an excess electron beyond a closed electronic may also exhibit alkali character. This approach based on shell-filling is the way alkali species are formed as explained by the periodic table. We demonstrate that the ionization energy of metallic clusters with both filled and unfilled electronic shells can be substantially lowered by attaching ligands. The ligands form charge transfer complexes where the electronic spectrum is lifted via crystal field like effect. We demonstrate that the effect works for the weakly bound ligand, N-ethyl-2-pyrrolidone (EP = C6H11NO), and that the effect leads to a dramatic lowering of the ionization energy independent of the shell occupancy of the cluster.
Carbon nitride supported Fe2 cluster catalysts with superior performance for alkene epoxidation
Authors: Tian Shubo , Fu Qiang , Chen Wenxing , Feng Quanchen , Chen Zheng , Zhang Jian , Cheong Weng-Chon , Yu Rong , Gu Lin , Dong Juncai , Luo Jun , Chen Chen , Peng Qing , Draxl Claudia , Wang Dingsheng , Li Yadong 
Published: June 2018

AbstractSub-nano metal clusters often exhibit unique and unexpected properties, which make them particularly attractive as catalysts. Herein, we report a “precursor-preselected” wet-chemistry strategy to synthesize highly dispersed Fe2 clusters that are supported on mesoporous carbon nitride (mpg-C3N4). The obtained Fe2/mpg-C3N4 sample exhibits superior catalytic performance for the epoxidation of trans-stilbene to trans-stilbene oxide, showing outstanding selectivity of 93% at high conversion of 91%. Molecular oxygen is the only oxidant and no aldehyde is used as co-reagent. Under the same condition, by contrast, iron porphyrin, single-atom Fe, and small Fe nanoparticles (ca. 3 nm) are nearly reactively inert. First-principles calculations reveal that the unique reactivity of the Fe2 clusters originates from the formation of active oxygen species. The general applicability of the synthesis approach is further demonstrated by producing other diatomic clusters like Pd2 and Ir2, which lays the foundation for discovering diatomic cluster catalysts.
Effect of temperature on Burkholderia pseudomallei growth, proteomic changes, motility and resistance to stress environments
Authors: Paksanont Suporn , Sintiprungrat Kitisak , Yimthin Thatcha , Pumirat Pornpan , Peacock Sharon J. , Chantratita Narisara 
Published: June 2018

AbstractBurkholderia pseudomallei is a flagellated, gram-negative environmental bacterium that causes melioidosis, a severe infectious disease of humans and animals in tropical areas. We hypothesised that B. pseudomallei may undergo phenotypic adaptation in response to an increase in growth temperature. We analysed the growth curves of B. pseudomallei strain 153 cultured in Luria–Bertani broth at five different temperatures (25 °C–42 °C) and compared the proteomes of bacteria cultured at 37 °C and 42 °C. B. pseudomallei exhibited the highest growth rate at 37 °C with modest reductions at 30 °C, 40 °C and 42 °C but a more marked delay at 25 °C. Proteome analysis revealed 34 differentially expressed protein spots between bacterial cultures at 42 °C versus 37 °C. These were identified as chaperones (7 spots), metabolic enzymes (12 spots), antioxidants (10 spots), motility proteins (2 spots), structural proteins (2 spots) and hypothetical proteins (1 spot). Of the 22 down-regulated proteins at 42 °C, redundancy in motility and antioxidant proteins was observed. qRT-PCR confirmed decreased expression of fliC and katE. Experiments on three B. pseudomallei strains demonstrated that these had the highest motility, greatest resistance to H2O2 and greatest tolerance to salt stress at 37 °C. Our data suggest that temperature affects B. pseudomallei motility and resistance to stress.
Comparison of Two Protocols of Carbon Tetrachloride-Induced Cirrhosis in Rats – Improving Yield and Reproducibility
Authors: Fortea José I , Fernández-Mena Carolina , Puerto Marta , Ripoll Cristina , Almagro Jorge , Bañares Juan , Bellón José M. , Bañares Rafael , Vaquero Javier 
Published: June 2018

AbstractDespite being a cardinal experimental model, the induction of cirrhosis in rats by repeated exposure to carbon tetrachloride (CCl4) has low reproducibility. Here, we compared two models of cirrhosis induced by orogastric administration of CCl4 once (CCl4-1xWk) or twice a week (CCl4-2xWk) for 12 weeks in male Sprague-Dawley rats. Control rats received water instead of CCl4. Both CCl4 protocols similarly attenuated body weight gain (p < 0.01 vs. Control). Although both CCl4 protocols increased hepatic fibrosis, portal hypertension and splenomegaly, the magnitude of these alterations was higher and more consistent in CCl4-2xWk rats. Importantly, two CCl4-1xWk rats did not develop cirrhosis versus a 100% yield of cirrhosis in CCl4-2xWk rats. The CCl4-2xWk protocol consistently induced liver atrophy together with hematological, biochemical and coagulation abnormalities characteristic of advanced cirrhosis that were absent in CCl4-1xWk rats. Ascites occurred in 20% and 80% of rats in theCCl4-1xWk and CCl4-2xWk groups (p < 0.01). All rats showed normal renal function, arterial blood gases and stable systemic hemodynamics. The total dose of CCl4 and mortality rate were similar in both protocols. The CCl4-2xWk protocol, therefore, was highly reproducible and effective for the induction of experimental cirrhosis within a confined time, representing a valuable advance for liver research.
Acceptability of placebo multiparticulate formulations in children and adults
Authors: Lopez Felipe L. , Mistry Punam , Batchelor Hannah K. , Bennett Joanne , Coupe Alastair , Ernest Terry B. , Orlu Mine , Tuleu Catherine 
Published: June 2018

AbstractPatient acceptability is an important consideration in the design of medicines for children. The aim of this study was to investigate acceptability of multiparticulates in healthy children and adults. A randomised, single-blind acceptability testing was performed involving 71 children (4–12 years) and 61 adults (18–37 years). Each participant received three 500 mg samples of microcrystalline cellulose pellets administered on a medicine spoon with water at 5–10 minutes intervals. Acceptability was measured based on voluntary intake of the samples, facial expressions, ratings on hedonic scales and reported willingness to take multiparticulates everyday as a medicine. Multiparticulates were voluntarily swallowed by 92% of children and 100% of adults. However, palatability issues were identified, with emphasis on textural aspects. Grittiness perception received negative ratings on hedonic scales by 60% of children and 51% of adults. Researcher observations revealed that 72% of children and 42% of adults displayed negative facial expressions towards the samples. Children reported their willingness to take multiparticulates as a medicine in 30% of the cases, compared to 74% in adults. This study demonstrates that multiparticulates may be a suitable formulation platform for children and adults, although palatability concerns have been highlighted. Additional work is required to define acceptability criteria and to standardise methodologies.
Identification of rice landraces with promising yield and the associated genomic regions under low nitrogen
Authors: Rao I. Subhakara , Neeraja C. N. , Srikanth B. , Subrahmanyam D. , Swamy K. N. , Rajesh K. , Vijayalakshmi P. , Kiran T. Vishnu , Sailaja N. , Revathi P. , Rao P. Raghuveer , Rao L. V. Subba , Surekha K. , Babu V. Ravindra , Voleti S. R. 
Published: June 2018

AbstractWith the priority of the low input sustainable rice cultivation for environment friendly agriculture, NUE of rice becomes the need of the hour. A set of 472 rice genotypes comprising landraces and breeding lines were evaluated for two seasons under field conditions with low and recommended nitrogen and >100 landraces were identified with relative higher yield under low nitrogen. Donors were identified for higher N uptake, N translocation into grains and grain yield under low N. Grains on secondary branches, N content in grain and yield appears to be the selection criterion under low N. Through association mapping, using minimum marker set of 50 rice SSR markers, 12 genomic regions were identified for yield and yield associated traits under low nitrogen. Four associated genomic regions on chromosomes 5, 7 and 10 were fine mapped and QTL for yield under low N were identified from the marker delimited regions. Three candidate genes viz., 2-oxoglutarate /malate translocator (Os05g0208000), alanine aminotransferase (Os07g0617800) and pyridoxal phosphate-dependent transferase (Os10g0189600) from QTL regions showed enhanced expression in the genotypes with promising yield under low N. Marker assisted selection using SSR markers associated with three candidate genes identified two stable breeding lines confirmed through multi-location evaluation.
Fish mitigate trophic depletion in marine cave ecosystems
Authors: Bussotti Simona , Di Franco Antonio , Bianchi Carlo Nike , Chevaldonné Pierre , Egea Lea , Fanelli Emanuela , Lejeusne Christophe , Musco Luigi , Navarro-Barranco Carlos , Pey Alexis , Planes Serge , Vieux-Ingrassia Jean Vincent , Guidetti Paolo 
Published: June 2018

AbstractDark marine habitats are often characterized by a food-limited condition. Peculiar dark habitats include marine caves, characterized by the absence of light and limited water flow, which lead to reduced fluxes of organic matter for cave-dwelling organisms. We investigated whether the most abundant and common cave-dwelling fish Apogon imberbis has the potential to play the role of trophic vector in Mediterranean marine caves. We first analysed stomach contents to check whether repletion changes according to a nycthemeral cycle. We then identified the prey items, to see whether they belong to species associated with cave habitats or not. Finally, we assessed whether A. imberbis moves outside marine caves at night to feed, by collecting visual census data on A. imberbis density both inside and outside caves, by day and by night. The stomach repletion of individuals sampled early in the morning was significantly higher than later in the day. Most prey were typical of habitats other than caves. A. imberbis was on average more abundant within caves during the day and outside during the night. Our study supports the hypothesis regarding the crucial trophic role of A. imberbis in connecting Mediterranean marine caves with external habitats.
A gene co-expression network model identifies yield-related vicinity networks in Jatropha curcas shoot system
Authors: Govender Nisha , Senan Siju , Mohamed-Hussein Zeti-Azura , Wickneswari Ratnam 
Published: June 2018

AbstractThe plant shoot system consists of reproductive organs such as inflorescences, buds and fruits, and the vegetative leaves and stems. In this study, the reproductive part of the Jatropha curcas shoot system, which includes the aerial shoots, shoots bearing the inflorescence and inflorescence were investigated in regard to gene-to-gene interactions underpinning yield-related biological processes. An RNA-seq based sequencing of shoot tissues performed on an Illumina HiSeq. 2500 platform generated 18 transcriptomes. Using the reference genome-based mapping approach, a total of 64 361 genes was identified in all samples and the data was annotated against the non-redundant database by the BLAST2GO Pro. Suite. After removing the outlier genes and samples, a total of 12 734 genes across 17 samples were subjected to gene co-expression network construction using petal, an R library. A gene co-expression network model built with scale-free and small-world properties extracted four vicinity networks (VNs) with putative involvement in yield-related biological processes as follow; heat stress tolerance, floral and shoot meristem differentiation, biosynthesis of chlorophyll molecules and laticifers, cell wall metabolism and epigenetic regulations. Our VNs revealed putative key players that could be adapted in breeding strategies for J. curcas shoot system improvements.
The microRNA-10a/ID3/RUNX2 axis modulates the development of Ossification of Posterior Longitudinal Ligament
Authors: Xu Chen , Zhang Hao , Gu Wei , Wu Huiqiao , Chen Yuanyuan , Zhou Wenchao , Sun Baifeng , Shen Xiaolong , Zhang Zicheng , Wang Yue , Liu Yang , Yuan Wen 
Published: June 2018

AbstractOssification of the posterior longitudinal ligament (OPLL) presents as pathological heterotopic ossification of the spinal ligaments. However, its underlying molecular mechanism is still unclear. Our previous findings suggested that altered microRNA regulatory network are critical for the development of OPLL. Here, we set out to unveiling the detailed mechanism of those altered OPLL-specific microRNAs. We screened a set of differentially expressed OPLL-specific microRNAs from the previous sequencing data and showed that microRNA-10a actively modulates the ossification of posterior ligament cells in vitro. Using a tissue-engineered scaffold grown from 4-week-old BALB/c homozygous nude mice, we found that altered microRNA-10a expression in posterior ligament cells indeed affected the heterotopic bone formation in vivo. Furthermore, computational analysis showed that the negative ossification regulator ID3 is a functional target gene of microRNA-10a, and its expression was also significantly altered during microRNA-10a modulation both in vitro and in vivo. Also, we have demonstrated that the ossification promoting function of microRNA-10a requires ID3, as ID3 actively inhibits RUNX2. Thus, we identified a critical role for highly altered OPLL-specific microRNA-10a in regulating the development of OPLL by modulating the ID3/RUNX2 axis.
Accurate and precise real-time RT-PCR assays for the identification of astrovirus associated encephalitis in cattle
Authors: Lüthi Ramona , Boujon Céline L. , Kauer Ronja , Koch Michel C. , Bouzalas Ilias G. , Seuberlich Torsten 
Published: June 2018

AbstractA novel bovine astrovirus genotype species (BoAstV-CH13/NeuroS1) was recently identified in brain tissues of cattle as a plausible cause of encephalitis. The purpose of the present study was to develop and validate real time RT-PCR assays for the detection of BoAstV-CH13/NeuroS1 in brain tissues of cattle. Three different primer-probe combinations were designed based on BoAstV-CH13/NeuroS1 full-genome sequences of 11 different strains identified in cattle, and established in three distinct one-step real time RT-PCR protocols. These protocols were compared regarding their diagnostic performance using brain tissues of cattle with and without astrovirus associated encephalitis. The limit of detection (LOD) of all three assays was between 1.34 × 101 and 1.34 × 102 RNA copies, leading to an analytical sensitivity two orders of magnitude superior compared to a conventional pan-astrovirus RT-PCR protocol (LOD 1.31 × 104 RNA copies). Amplification efficiency was in the range of 97.3% to 107.5% with linearity (R2) > 0.99. The diagnostic sensitivity and specificity of the assays was determined as 100%, and all three revealed good intra- and inter-test repeatability. In conclusion, the newly developed RT-qPCRs are sensitive, specific, and reliable test formats that will facilitate BoAstV-CH13/NeuroS1 detection in routine diagnostics as well as in research settings.
Micro-scale, mid-scale, and macro-scale in global seismicity identified by empirical mode decomposition and their multifractal characteristics
Authors: Sarlis Nicholas V. , Skordas Efthimios S. , Mintzelas Apostolis , Papadopoulou Konstantina A. 
Published: June 2018

AbstractThe magnitude time-series of the global seismicity is analyzed by the empirical mode decomposition giving rise to 14 intrinsic mode functions (IMF) and a trend. Using Hurst analysis one can identify three different sums of these IMFs and the trend which exhibit distinct multifractal behaviour and correspond to micro-, mid- and macro-scales. Their multifractal detrended fluctuation analysis reveals that the micro-scale time-series exhibits anticorrelated behaviour in contrast to the mid-scale one which is long-range correlated. Concerning the mid-scale one, in the range of 30 to 300 consecutive events the maximum entropy method power spectra indicates that it exhibits an 1/fα behaviour with α close to 1/3 which is compatible with the long-range correlations identified by detrended fluctuation analysis during periods of stationary seismicity. The results have been also verified to hold regionally for the earthquakes in Japan and shed light on the significance of the mid-scale of 30 to 300 events in the natural time analysis of global (and regional) seismicity. It is shown that when using the mid-scale time-series only, we can obtain results similar to those obtained by the natural time analysis of global seismicity when focusing on the prediction of earthquakes with M ≥ 8.4.
Inhibitory effect of SLIT2 on granulosa cell proliferation mediated by the CDC42-PAKs-ERK1/2 MAPK pathway in the prehierarchical follicles of the chicken ovary
Authors: Xu Rifu , Qin Ning , Xu Xiaoxing , Sun Xue , Chen Xiaoxia , Zhao Jinghua 
Published: June 2018

AbstractThe SLIT2 ligand and ROBO receptors of the SLIT/ROBO pathway are expressed in hen ovarian follicles and have been shown to play critical roles in ovary development, cell proliferation and apoptosis in mammals. However, the exact roles of SLIT2 and the molecular mechanisms of chicken follicle development remain poorly understood. Here, we discovered that high levels of SLIT2 suppress FSHR, GDF9, STAR and CYP11A1 mRNA and protein expression in granulosa cells (GCs) and cell proliferation (p < 0.01). However, these inhibitory effects can be abolished by the siRNA-mediated knockdown of the ROBO1 and ROBO2 receptors. Furthermore, the activity of CDC42, which is a key Rho GTPase in the SLIT/ROBO pathway, is regulated by the ligand SLIT2 because the intrinsic GTPase activation activity of CDC42 is activated or repressed by regulating SRGAP1 expression (p < 0.01). The effects of the SLIT2 overexpression on GC proliferation and phosphorylation of the B-RAF, RAF1 and ERK1/2 kinases were completely abrogated by knocking down endogenous PAK1 and partially abrogated by the knockdown of PAK2 and PAK3 in the GCs. Collectively, our findings indicate that SLIT2 suppresses GC proliferation, differentiation and follicle selection mainly by a mechanism involving ROBO1 and ROBO2 and that this suppression is mediated by the CDC42-PAKs-ERK1/2 MAPK signaling cascade in the prehierarchical follicles of the chicken ovary.