bluuebunny/crossref_metadata_2025_split huggingface dataset:
X-ray spectroscopy of massive stellar winds: previous and ongoing observations of the hot star ζ Pup
Authors: Miller N. , Waldron W. , Nichols J. , Huenemoerder D. , Dahmer M. , Ignace R. , Lauer J. , Moffat A. , Nazé Y. , Oskinova L. , Richardson N. , Ramiaramanantsoa T. , Shenar T. , Gayley K. 
Published: December 2019

AbstractThe stellar winds of hot stars have an important impact on both stellar and galactic evolution, yet their structure and internal processes are not fully understood in detail. One of the best nearby laboratories for studying such massive stellar winds is the O4I(n)fp star ζ Pup. After briefly discussing existing X-ray observations from Chandra and XMM, we present a simulation of X-ray emission line profile measurements for the upcoming 840 kilosecond Chandra HETGS observation. This simulation indicates that the increased S/N of this new observation will allow several major steps forward in the understanding of massive stellar winds. By measuring X-ray emission line strengths and profiles, we should be able to differentiate between various stellar wind models and map the entire wind structure in temperature and density. This legacy X-ray spectrum of ζ Pup will be a useful benchmark for future X-ray missions.
The Formation of Continental Fragments in Subduction Settings: The Importance of Structural Inheritance and Subduction System Dynamics
Authors: van den Broek J.M. , Magni V. , Gaina C. , Buiter S.J.H. 
Published: December 2019

AbstractMicrocontinents and continental fragments are pieces of continental lithosphere, formed by extension and breakup, followed by plate boundary relocations. Microcontinents or continental fragments affiliated with passive margins are well documented, but those close to active margins are less studied. We use dynamic two‐ and three‐dimensional numerical experiments to investigate how preexisting weaknesses within a continental upper plate affect extension and the possible formation of continental fragments. Our parametric study of the configuration (width and viscosity) of this imposed weakness indicates that stress localization and breakup of the upper plate are most efficient for narrow weak zones and a viscosity contrast between the weak zone and the surrounding crust of at least 1 order of magnitude. Moreover, upper plate extension and breakup occurs only if extension has a rotational component, here caused by the presence of a continental indenter on the downgoing plate. The width of the indenter relative to oceanic part of the downgoing plate controls differential slab pull that triggers trench retreat and upper plate deformation. A downgoing plate with a relatively large continental indenter yields large enough slab rotation to detach a continental block from the overriding plate and form wide back‐arc basins. Variations in the weak zone angle with respect to the trench result in different basin geometries. We successfully modeled the first step in breakup of active continental margins and determined the settings that may facilitate microcontinent formation in a subduction framework.
The Effects of River Algae and Pore Water Flow on the Feeding of Juvenile Mussels
Authors: Fung Victor , Ackerman Josef D. 
Published: December 2019

AbstractJuvenile mussels enter the benthos after excysting from a fish host and settling to the bottom where they inhabit the interstitial zone in rivers. We examined the algal composition in the surface water and pore waters in different locations in a temperate river (Thames River) in Southern Ontario. Surprisingly, algal concentration (C) was ~9× higher in pore water versus surface water and varied spatially in the riverbed (downstream of boulders > upstream of boulders and nonbedform regions), and pennate diatoms were the most abundant taxon in the pore waters. We examined the clearance rate (CR; mass of suspended material removed from the water per unit time and mussel) of recently metamorphosed juvenile unionid mussels (3‐ to 4‐week‐old Lampsilis siliquoidea, Fatmuckets) exposed to pore water and surface water in a paddle wheel flow chamber at different water velocities (U). Juvenile CR based on Chlorophyll a fluorescence was ~2× higher on pore water versus surface water and CR based on a specific algal taxon, identified via flow cytometry, varied with its initial concentration. Chesson's feeding electivity index revealed that mussels removed five chlorophyte taxa in proportion to their concentration in the water (i.e., removed at random), but they removed five diatom taxa in greater proportion (i.e., selected for by juvenile mussels) across the range of algal flux (J = UC) examined. This study provides evidence of the importance of diatoms in pore waters to juvenile mussels. It also reveals elements of the physicochemical environment used by juvenile mussels, which should be considered in their conservation.
Development of an autonomous solvent extraction system to isolate astatine-211 from dissolved cyclotron bombarded bismuth targets
Authors: O’Hara Matthew J. , Krzysko Anthony J. , Hamlin Donald K. , Li Yawen , Dorman Eric F. , Wilbur D. Scott 
Published: December 2019

AbstractCyclotron-produced astatine-211 (211At) shows tremendous promise in targeted alpha therapy (TAT) applications due to its attractive half-life and its 100% α-emission from nearly simultaneous branched alpha decay. Astatine-211 is produced by alpha beam bombardment of naturally monoisotopic bismuth metal (209Bi) via the (α, 2n) reaction. In order to isolate the small mass of211At (specific activity = 76 GBq·µg−1) from several grams of acid-dissolved Bi metal, a manual milliliter-scale solvent extraction process using diisopropyl ether (DIPE) is routinely performed at the University of Washington. As this process is complex and time consuming, we have developed a fluidic workstation that can perform the method autonomously. The workstation employs two pumps to concurrently deliver the aqueous and organic phases to a mixing tee and in-line phase mixer. The mixed phases are routed to a phase settling reservoir, where they gravity settle. Finally, each respective phase is withdrawn into its respective pump. However, development of a phase boundary sensor, placed in tandem with the phase settling reservoir, was necessary to communicate to the system when withdrawal of the denser aqueous phase was complete (i.e., the intersection of the two phases was located). The development and optimization of the autonomous solvent extraction system is described, and the211At yields from several ~1.1 GBq-level211At processing runs are reported.
Synthesis and Evaluation of Anisomelic acid-like Compounds for the Treatment of HPV-Mediated Carcinomas
Authors: Senthilkumar Rajendran , Brusentsev Yury , Paul Preethy , Marimuthu Parthiban , Cheng Fang , Eklund Patrik C. , Eriksson John Elias 
Published: December 2019

AbstractThe vast majority of cervical and 75% of oropharyngeal carcinomas are triggered by infection with a type of high-risk oncogenic human papillomavirus (HPV). It is well-known that E6 and E7 oncoproteins are critical for viral-induced cancer, and hence, they represent valuable targets for therapeutic intervention in HPV-mediated cancers. Our earlier research on the cembranoid, anisomelic acid (AA) showed that, AA has the potential to induce apoptosis in HPV cells by the depletion of E6 and E7 oncoproteins. The present study describes the structure-activity relationship and the evaluation of synthetic AA like compounds, i.e simplified cembranoid-like structures, as HPV inhibitors against some papilloma cell lines. Both from experimental and computational results, we observed that these compounds induced apoptosis by the same E6/E7-based mechanism as AA, but at earlier time points, thus being far more effective than AA. Further, the data indicated that only part of the structure of AA is required for the molecular action. Based on these results, we identified some novel and potential compounds for specific treatment of HPV-associated carcinomas.
OXS2 is Required for Salt Tolerance Mainly through Associating with Salt Inducible Genes, CA1 and Araport11, in Arabidopsis
Authors: Jing Ying , Shi Lin , Li Xin , Zheng Han , Gao Jianwei , Wang Mei , He Lilong , Zhang Wei 
Published: December 2019

AbstractSalt stress is one of the abiotic stresses affecting crop growth and yield. The functional screening and mechanism investigation of the genes in response to salt stress are essential for the development of salt-tolerant crops. Here, we found that OXIDATIVE STRESS 2 (OXS2) was a salinity-induced gene, and the mutant oxs2-1 was hypersensitive to salt stress during seed germination and root elongation processes. In the absence of stress, OXS2 was predominantly localized in the cytoplasm; when the plants were treated with salt, OXS2 entered the nuclear. Further RNA-seq analysis and qPCR identification showed that, in the presence of salt stress, a large number of differentially expressed genes (DEGs) were activated, which contain BOXS2 motifs previously identified as the binding element for AtOXS2. Further ChIP analysis revealed that, under salt stress, OXS2 associated with CA1 and Araport11 directly through binding the BOXS2 containing fragments in the promoter regions. In conclusion, our results indicate that OXS2 is required for salt tolerance in Arabidopsis mainly through associating with the downstream CA1 and Araport11 directly.
Sensitive detection of EBV microRNAs across cancer spectrum reveals association with decreased survival in adult acute myelocytic leukemia
Authors: Movassagh Mercedeh , Oduor Cliff , Forconi Catherine , Moormann Ann M. , Bailey Jeffrey A. 
Published: December 2019

AbstractEpstein Barr virus (EBV) is the etiologic agent involved in numerous human cancers. After infecting the host, EBV establishes a latent infection, with low levels of messenger RNA (mRNA) and protein expression, evolved to evade immune recognition. Conversely, EBV microRNAs (miRNA) are expressed ubiquitously and abundantly within infected cells. Their role in tumor biology and clinical outcomes across the spectrum of cancer is not fully explained. Here, we applied our bioinformatics pipeline for quantitative EBV miRNA detection to examine sequencing data of 8,955 individual tumor samples across 27 tumor types representing the breadth of cancer. We uncover an association of intermediate levels of viral miRNA with decreased survival in adult acute myeloid leukemia (AML) patients (P = 0.00013). Prognostic modeling of this association suggests that increased EBV miRNA levels represent an independent risk factor for poor patient outcomes. Furthermore, we explore differences in expression between elevated and absent viral miRNA loads in adult AML tumors finding that EBV positivity was associated with proinflammatory signals. Together, given no associations were found for pediatric AML, our analyses suggests EBV positivity has the potential for being a prognostic biomarker and might represent a surrogate measure related to immune impairment in adult patients.
Genome mining and characterisation of a novel transaminase with remote stereoselectivity
Authors: Gavin D. P. , Reen F. J. , Rocha-Martin J. , Abreu-Castilla I. , Woods D. F. , Foley A. M. , Sánchez-Murcia P. A. , Schwarz M. , O’Neill P. , Maguire A. R. , O’Gara F. 
Published: December 2019

AbstractMicrobial enzymes from pristine niches can potentially deliver disruptive opportunities in synthetic routes to Active Pharmaceutical Ingredients and intermediates in the Pharmaceutical Industry. Advances in green chemistry technologies and the importance of stereochemical control, further underscores the application of enzyme-based solutions in chemical synthesis. The rich tapestry of microbial diversity in the oceanic ecosystem encodes a capacity for novel biotransformations arising from the chemical complexity of this largely unexplored bioactive reservoir. Here we report a novel ω-transaminase discovered in a marine sponge Pseudovibrio sp. isolate. Remote stereoselection using a transaminase has been demonstrated for the first time using this novel protein. Application to the resolution of an intermediate in the synthesis of sertraline highlights the synthetic potential of this novel biocatalyst discovered through genomic mining. Integrated chemico-genomics revealed a unique substrate profile, while molecular modelling provided structural insights into this ‘first in class’ selectivity at a remote chiral centre.
Enhancement of immune response against Bordetella spp. by disrupting immunomodulation
Authors: Gestal Monica C. , Howard Laura K. , Dewan Kalyan , Johnson Hannah M. , Barbier Mariette , Bryant Clare , Soumana Illiassou Hamidou , Rivera Israel , Linz Bodo , Blas-Machado Uriel , Harvill Eric T. 
Published: December 2019

AbstractWell-adapted pathogens must evade clearance by the host immune system and the study of how they do this has revealed myriad complex strategies and mechanisms. Classical bordetellae are very closely related subspecies that are known to modulate adaptive immunity in a variety of ways, permitting them to either persist for life or repeatedly infect the same host. Exploring the hypothesis that exposure to immune cells would cause bordetellae to induce expression of important immunomodulatory mechanisms, we identified a putative regulator of an immunomodulatory pathway. The deletion of btrS in B. bronchiseptica did not affect colonization or initial growth in the respiratory tract of mice, its natural host, but did increase activation of the inflammasome pathway, and recruitment of inflammatory cells. The mutant lacking btrS recruited many more B and T cells into the lungs, where they rapidly formed highly organized and distinctive Bronchial Associated Lymphoid Tissue (BALT) not induced by any wild type Bordetella species, and a much more rapid and strong antibody response than observed with any of these species. Immunity induced by the mutant was measurably more robust in all respiratory organs, providing completely sterilizing immunity that protected against challenge infections for many months. Moreover, the mutant induced sterilizing immunity against infection with other classical bordetellae, including B. pertussis and B. parapertussis, something the current vaccines do not provide. These findings reveal profound immunomodulation by bordetellae and demonstrate that by disrupting it much more robust protective immunity can be generated, providing a pathway to greatly improve vaccines and preventive treatments against these important pathogens.
Coconut shell derived biochar to enhance water spinach (Ipomoea aquatica Forsk) growth and decrease nitrogen loss under tropical conditions
Authors: Zhao Fengliang , Zou Ganghua , Shan Ying , Ding Zheli , Dai Minjie , He Zhenli 
Published: December 2019

AbstractFarms usually apply excessive nitrogen (N) fertilizers, especially in a vegetable production system, resulting in severe N leaching loss. Although there have been some reports on the impact of biochar on the N leaching in farmlands, most of them focused on field crops in temperate or subtropical religions. Limited information about N leaching in the tropical vegetable system is available regarding the quantitative data and effective countermeasures. A field experiment was conducted to quantify N leaching in a tropical leafy production system (Ipomoea aquatica Forsk) and to evaluate the effects of coconut shell biochar on N loss and crop growth. The results showed that compared to conventional fertilization with the 240 kg N ha−1 application rate (NPK), biomass yield of water spinach increased by 40.1% under the high biochar application rate of 48 t ha−1 (HBC), which was significantly higher than that of NPK treatment. Moreover, The HBC treatment decreased N leaching by 34.0%, which can be attributed to enhanced crop uptake which increased by 40.3% as compared to NPK treatment. The NH4+/NO3− ratio in leachates was between 0.01 and 0.05. It was concluded that coconut shell derived biochar improved the biomass yields of water spinach and reduced the leaching N loss, which provides a promising amendment in tropical regions.
Butyrate attenuated fat gain through gut microbiota modulation in db/db mice following dapagliflozin treatment
Authors: Oh Tae Jung , Sul Woo Jun , Oh Han Na , Lee Yun-Kyung , Lim Hye Li , Choi Sung Hee , Park Kyong Soo , Jang Hak Chul 
Published: December 2019

AbstractWe investigated the effect of a combination treatment with dapagliflozin (Dapa), a sodium-glucose cotransporter-2 inhibitor and butyrate on weight change in db/db mice. Six-week-old male db/db mice were assigned to four groups: vehicle with normal chow diet (NCD), Dapa with NCD, vehicle with 5% sodium butyrate-supplemented NCD (NaB), or Dapa with 5% NaB. After six weeks of treatment, faecal microbiota composition was analysed by sequencing 16S ribosomal RNA genes. In the vehicle with NaB and Dapa + NaB groups, body weight increase was attenuated, and amount of food intake decreased compared with the vehicle with the NCD group. The Dapa + NaB group gained the least total and abdominal fat from baseline. Intestinal microbiota of this group was characterized by a decrease of the Firmicutes to Bacteroidetes ratio, a decrease of Adlercreutzia and Alistipes, as well as an increase of Streptococcus. In addition, the proportion of Adlercreutzia and Alistipes showed a positive correlation with total fat gain, whereas Streptococcus showed a negative correlation. Inferred metagenome function revealed that tryptophan metabolism was upregulated by NaB treatment. We demonstrated a synergistic effect of Dapa and NaB treatment on adiposity reduction, and this phenomenon might be related to intestinal microbiota alteration.
Electrokinetics in Micro-channeled Cantilevers: Extending the Toolbox for Reversible Colloidal Probes and AFM-Based Nanofluidics
Authors: Mark Andreas , Helfricht Nicolas , Rauh Astrid , Xue Jinqiao , Knödler Patrick , Schumacher Thorsten , Karg Matthias , Du Binyang , Lippitz Markus , Papastavrou Georg 
Published: December 2019

AbstractThe combination of atomic force microscopy (AFM) with nanofluidics, also referred to as FluidFM, has facilitated new applications in scanning ion conductance microscopy, direct force measurements, lithography, or controlled nanoparticle deposition. An essential element of this new type of AFMs is its cantilever, which bears an internal micro-channel with a defined aperture at the end. Here, we present a new approach for in-situ characterization of the internal micro-channels, which is non-destructive and based on electrochemical methods. It allows for probing the internal environment of a micro-channeled cantilever and the corresponding aperture, respectively. Acquiring the streaming current in the micro-channel allows to determine not only the state of the aperture over a wide range of ionic strengths but also the surface chemistry of the cantilever’s internal channel. The high practical applicability of this method is demonstrated by detecting the aspiration of polymeric, inorganic and hydrogel particles with diameters ranging from several µm down to 300 nm. By verifying in-situ the state of the aperture, i.e. open versus closed, electrophysiological or nano-deposition experiments will be significantly facilitated. Moreover, our approach is of high significance for direct force measurements by the FluidFM-technique and sub-micron colloidal probes.
Time-Resolved Measurements of Turbulent Mixing in Shock-Driven Variable-Density Flows
Authors: Carter John , Pathikonda Gokul , Jiang Naibo , Felver Josef J. , Roy Sukesh , Ranjan Devesh 
Published: December 2019

AbstractRecent developments of burst-mode lasers and imaging systems have opened new realms of simultaneous diagnostics for velocity and density fields at a rate of 1 kHz–1 MHz. These enable the exploration of previously unimaginable shock-driven turbulent flow fields that are of significant importance to problems in high-energy density physics. The current work presents novel measurements using simultaneous measurements of velocity and scalar fields at 60 kHz to investigate Richtmyer-Meshkov instability (RMI) in a spatio-temporal approach. The evolution of scalar fields and the vorticity dynamics responsible for the same are shown, including the interaction of shock with the interface. This temporal information is used to validate two vorticity-deposition models commonly used for initiation of large scale simulations, and have been previously validated only via simulations or integral measures of circulation. Additionally, these measurements also enable tracking the evolution and mode merging of individual flow structures that were previously not possible owing to inherently random variations in the interface at the smallest scales. A temporal evolution of symmetric vortex merging and the induced mixing prevalent in these problems is presented, with implications for the vortex paradigms in accelerated inhomogenous flows.
Graphene plasmonically induced analogue of tunable electromagnetically induced transparency without structurally or spatially asymmetry
Authors: He Yuwen , Zhang Jianfa , Xu Wei , Guo Chucai , Liu Ken , Yuan Xiaodong , Zhu Zhihong 
Published: December 2019

AbstractElectromagnetically induced transparency (EIT) arises from the coherent coupling and interference between a superradiant (bright) mode in one resonator and a subradiant (dark) mode in an adjacent resonator. Generally, the two adjacent resonators are structurally or spatially asymmetric. Here, by numerical simulation, we demonstrate that tunable EIT can be induced by graphene ribbon pairs without structurally or spatially asymmetry. The mechanism originates from the fact that the resonate frequencies of the bright mode and the dark mode supported by the symmetrical graphene ribbon pairs can be respectively tuned by electrical doping levels, and when they are tuned to be equal the graphene plasmon coupling and interference occurs. The EIT in symmetrical nanostructure which avoids deliberately breaking the element symmetry in shape as well as in size facilitates the design and fabrication of the structure. In addition, the work regarding to EIT in the structurally symmetric could provide a fresh contribution to a more comprehensive physical understanding of Fano resonance.
High order Fano resonances and giant magnetic fields in dielectric microspheres
Authors: Wang Zengbo , Luk’yanchuk Boris , Yue Liyang , Yan Bing , Monks James , Dhama Rakesh , Minin Oleg V. , Minin Igor V. , Huang Sumei , Fedyanin Andrey A. 
Published: December 2019

AbstractWe show that weakly dissipating dielectric spheres made of materials such as glass, quartz, etc. can support high order Fano resonances associated with internal Mie modes. These resonances, happening for specific values of the size parameter, yield field-intensity enhancement factors on the order of 104–107, which can be directly obtained from analytical calculations. Associated to these “super-resonances”, we analyze the emergence of magnetic nanojets with giant magnetic fields, which might be attractive for many photonic applications.
Effect of long anther dehiscence on seed set at high temperatures during flowering in rice (Oryza sativa L.)
Authors: Matsui Tsutomu , Hasegawa Toshihiro 
Published: December 2019

AbstractCountermeasures that can mitigate the global warming impact on rice production are needed. The large dehiscence of anther for pollen dispersal is one trait that shows tolerance of seed set to high temperatures under the global warming. The aim of this study is to determine the effect of long anther dehiscence on high temperature tolerance. Seven chromosome segment substitution lines and the seed parent with the different dehiscence lengths were subjected to high daytime temperatures. Elongation of dehiscence formed at the base of anther (BDL) by 100 µm mitigated the occurrence of high temperature induced sterility by 20% and improved tolerance to the high temperature by 0.66 °C. Relationship between the seed set and BDL was well explained by pollination, showing that quantitative information provided in the present experiment is reliable. The information is expected to be used in estimation of global warming impact and making countermeasures for it.