bluuebunny/crossref_metadata_2025_split huggingface dataset:
Blue Optical Observations of Narrow Bipolar Events by ASIM Suggest Corona Streamer Activity in Thunderstorms
Authors: Soler S. , Pérez‐Invernón F. J. , Gordillo‐Vázquez F. J. , Luque A. , Li D. , Malagón‐Romero A. , Neubert T. , Chanrion O. , Reglero V. , Navarro‐Gonzalez J. , Lu G. , Zhang H. , Huang A. , Østgaard N. 
Published: July 2020

AbstractWhile narrow bipolar events (NBEs) could be related with lightning initiation, their intrinsic physics remains in question. Here we report on optical measurements by the Atmosphere‐Space Interactions Monitor (ASIM) on the International Space Station (ISS) of blue flashes associated with NBEs. They are observed in a narrow blue band centered at 337 nm, with no simultaneous activity at 777.4 nm, considered a strong lightning emission line. From radio waves measured from the ground, we find that 7 of 10 single‐pulse blue events can be identified as positive NBEs. The source altitudes estimated from optical and radio signals agree and indicate that the sources of the blue flashes are located between∼8.5 and∼14 km, in a cloud reaching 14–15 km altitude. The observations suggest that single‐pulse blue flashes are from cold ionization waves, so‐called streamers, and that positive NBEs are corona discharges formed by many streamers.
Evaluating Cropland N2O Emissions and Fertilizer Plant Greenhouse Gas Emissions With Airborne Observations
Authors: Gvakharia A. , Kort E. A. , Smith M. L. , Conley S. 
Published: July 2020

AbstractAgricultural activity is a significant source of greenhouse gas emissions. The fertilizer production process emits N2O, CO2, and CH4, and fertilized croplands emit N2O. We present continuous airborne observations of these trace gases in the Lower Mississippi River Basin to quantify emissions from both fertilizer plants and croplands during the early growing season. Observed hourly emission rates from two fertilizer plants are compared with reported inventory values, showing agreement for N2O and CO2 emissions but large underestimation in reported CH4 emissions by up to a factor of 100. These CH4 emissions are consistent with loss rates of 0.6–1.2%. We quantify regional emission fluxes (100 km) of N2O using the airborne mass balance technique, a first application for N2O, and explore linkages to controlling processes. Finally, we demonstrate the ability to use airborne measurements to distinguish N2O emission differences between neighboring fields, determining we can distinguish different emission behaviors of regions on the order of 2.5 km2 with emissions differences of approximately 0.026 μmol m−2 s−1. This suggests airborne approaches such as outlined here could be used to evaluate the impact of different agricultural practices at critical field‐size spatial scales.
Corona Discharge in Wind for Electrically Isolated Electrodes
Authors: Guerra‐Garcia C. , Nguyen N. C. , Mouratidis T. , Martinez‐Sanchez M. 
Published: July 2020

AbstractFor various problems in atmospheric electricity it is necessary to understand the behavior of corona discharge in wind. Prior work considers grounded electrode systems, of relevance for earthed towers, trees, or windmills subjected to thunderstorms fields. In this configuration, the effect of wind is to remove the shielding ions from the coronating electrode vicinity strengthening the corona and increasing its current. There are a number of cases, such as isolated wind turbine blades or airborne vehicles, that are not completely represented by the available models and experiments. This paper focuses on electrode systems that are electrically isolated from their environment and reports on a wind tunnel campaign and accompanying theoretical work. In this configuration, there are two competing effects: the removal of the shielding ions by the wind, strengthening the corona; and the electrode system charging negatively (for positive corona) with respect to its environment, weakening the corona. This leads to three different operating regimes; namely, for positions that favor ion recapture, charging is limited and current increases with wind as in the classical scaling; for positions that favor ion transport by the wind, the system charges negatively and the current decreases with wind; for the later configuration, as wind increases, the current can vanish and the system potential saturates. The results from this work demonstrate that classical scaling laws of corona discharge in wind do not necessarily apply for isolated electrodes and illustrate the feasibility of using a glow corona in wind for controlled charging of a floating body.
Identification of Optimum Temperatures for Photosynthetic Production in Subtropical Coastal Ecosystems: Implications for CO2 Sequestration in a Warming World
Authors: McGowan Hamish A. , Lowry Andrew L. , Gray Michael A. 
Published: July 2020

AbstractTerrestrial ecosystems are often thought to be effective sinks of anthropogenic CO2 emissions with biosphere greening considered unequivocal evidence of this process. Increasing atmospheric concentrations of CO2 along with other greenhouse gases are however, responsible for global warming. As temperature increases, the rate at which biomes sequester CO2 may decline as the optimum temperature for photosynthetic production is exceeded, thereby reducing their potential to sequester CO2. Here we present evidence from 3 years of direct measurements of CO2 exchanges over subtropical coastal ecosystems in eastern Australia that the optimum temperature range for photosynthesis of 24.1°C to 27.4°C is routinely exceeded. This causes a rapid decline in photosynthetic production made worse when soil water content decreases. As climate change continues, both rising temperatures and predicted decline in rainfall will see these coastal ecosystems ability to sequester CO2 decrease further rapidly. We suggest similar research is needed urgently over other terrestrial ecosystems.
Ryk modulates the niche activity of mesenchymal stromal cells by fine-tuning canonical Wnt signaling
Authors: Jeong Seon-Yeong , Lyu Jungmook , Kim Jin-A , Oh Il-Hoan 
Published: July 2020

AbstractThe importance of modulating the intensity of Wnt signaling has been highlighted in various biological models, but their mechanisms remain unclear. In this study, we found that Ryk—an atypical Wnt receptor with a pseudokinase domain—has a Wnt-modulating effect in bone marrow stromal cells to control hematopoiesis-supporting activities. We first found that Ryk is predominantly expressed in the mesenchymal stromal cells (MSCs) of the bone marrow (BM) compared with hematopoietic cells. Downregulation of Ryk in MSCs decreased their clonogenic activity and ability to support self-renewing expansion of primitive hematopoietic progenitors (HPCs) in response to canonical Wnt ligands. In contrast, under high concentrations of Wnt, Ryk exerted suppressive effects on the transactivation of target genes and HPC-supporting effects in MSCs, thus fine-tuning the signaling intensity of Wnt in BM stromal cells. This ability of Ryk to modulate the HPC-supporting niche activity of MSCs was abrogated by induction of deletion mutants of Ryk lacking the intracellular domain or extracellular domain, indicating that the pseudokinase-containing intracellular domain mediates the Wnt-modulating effects in response to extracellular Wnt ligands. These findings indicate that the ability of the BM microenvironment to respond to extracellular signals and support hematopoiesis may be fine-tuned by Ryk via modulation of Wnt signaling intensity to coordinate hematopoietic activity.
Aerobic microbial life persists in oxic marine sediment as old as 101.5 million years
Authors: Morono Yuki , Ito Motoo , Hoshino Tatsuhiko , Terada Takeshi , Hori Tomoyuki , Ikehara Minoru , D’Hondt Steven , Inagaki Fumio 
Published: July 2020

AbstractSparse microbial populations persist from seafloor to basement in the slowly accumulating oxic sediment of the oligotrophic South Pacific Gyre (SPG). The physiological status of these communities, including their substrate metabolism, is previously unconstrained. Here we show that diverse aerobic members of communities in SPG sediments (4.3‒101.5 Ma) are capable of readily incorporating carbon and nitrogen substrates and dividing. Most of the 6986 individual cells analyzed with nanometer-scale secondary ion mass spectrometry (NanoSIMS) actively incorporated isotope-labeled substrates. Many cells responded rapidly to incubation conditions, increasing total numbers by 4 orders of magnitude and taking up labeled carbon and nitrogen within 68 days after incubation. The response was generally faster (on average, 3.09 times) for nitrogen incorporation than for carbon incorporation. In contrast, anaerobic microbes were only minimally revived from this oxic sediment. Our results suggest that microbial communities widely distributed in organic-poor abyssal sediment consist mainly of aerobes that retain their metabolic potential under extremely low-energy conditions for up to 101.5 Ma.
Global reward state affects learning and activity in raphe nucleus and anterior insula in monkeys
Authors: Wittmann Marco K. , Fouragnan Elsa , Folloni Davide , Klein-Flügge Miriam C. , Chau Bolton K. H. , Khamassi Mehdi , Rushworth Matthew F. S. 
Published: July 2020

AbstractPeople and other animals learn the values of choices by observing the contingencies between them and their outcomes. However, decisions are not guided by choice-linked reward associations alone; macaques also maintain a memory of the general, average reward rate – the global reward state – in an environment. Remarkably, global reward state affects the way that each choice outcome is valued and influences future decisions so that the impact of both choice success and failure is different in rich and poor environments. Successful choices are more likely to be repeated but this is especially the case in rich environments. Unsuccessful choices are more likely to be abandoned but this is especially likely in poor environments. Functional magnetic resonance imaging (fMRI) revealed two distinct patterns of activity, one in anterior insula and one in the dorsal raphe nucleus, that track global reward state as well as specific outcome events.
Butyrophilin-like proteins display combinatorial diversity in selecting and maintaining signature intraepithelial γδ T cell compartments
Authors: Jandke Anett , Melandri Daisy , Monin Leticia , Ushakov Dmitry S. , Laing Adam G. , Vantourout Pierre , East Philip , Nitta Takeshi , Narita Tomoya , Takayanagi Hiroshi , Feederle Regina , Hayday Adrian 
Published: July 2020

AbstractButyrophilin-like (Btnl) genes are emerging as major epithelial determinants of tissue-associated γδ T cell compartments. Thus, the development of signature, murine TCRγδ+ intraepithelial lymphocytes (IEL) in gut and skin depends on Btnl family members, Btnl1 and Skint1, respectively. In seeking mechanisms underlying these profound effects, we now show that normal gut and skin γδ IEL development additionally requires Btnl6 and Skint2, respectively, and furthermore that different Btnl heteromers can seemingly shape different intestinal γδ+ IEL repertoires. This formal genetic evidence for the importance of Btnl heteromers also applied to the steady-state, since sustained Btnl expression is required to maintain the signature TCR.Vγ7+ IEL phenotype, including specific responsiveness to Btnl proteins. In sum, Btnl proteins are required to select and to maintain the phenotypes of tissue-protective γδ IEL compartments, with combinatorially diverse heteromers having differential impacts on different IEL subsets.
Necrotrophic lifestyle of Rhizoctonia solani AG3-PT during interaction with its host plant potato as revealed by transcriptome analysis
Authors: Zrenner Rita , Genzel Franziska , Verwaaijen Bart , Wibberg Daniel , Grosch Rita 
Published: July 2020

AbstractThe soil-borne pathogenRhizoctonia solaniinfects a broad range of plants worldwide and is responsible for significant crop losses.Rhizoctonia solaniAG3-PT attacks germinating potato sprouts underground while molecular responses during interaction are unknown. To gain insights into processes induced in the fungus especially at early stage of interaction, transcriptional activity was compared between growth of mycelium in liquid culture and the growing fungus in interaction with potato sprouts using RNA-sequencing. Genes coding for enzymes with diverse hydrolase activities were strongly differentially expressed, however with remarkably dissimilar time response. While at 3 dpi, expression of genes coding for peptidases was predominantly induced, strongest induction was found for genes encoding hydrolases acting on cell wall components at 8 dpi. Several genes with unknown function were also differentially expressed, thus assuming putative roles as effectors to support host colonization. In summary, the presented analysis characterizes the necrotrophic lifestyle ofR. solaniAG3-PT during early interaction with its host.
RNA-sequencing analysis revealed genes associated drought stress responses of different durations in hexaploid sweet potato
Authors: Arisha Mohamed Hamed , Ahmad Muhammad Qadir , Tang Wei , Liu Yaju , Yan Hui , Kou Meng , Wang Xin , Zhang Yungang , Li Qiang 
Published: July 2020

AbstractPurple-fleshed sweet potato (PFSP) is an important food crop, as it is a rich source of nutrients and anthocyanin pigments. Drought has become a major threat to sustainable sweetpotato production, resulting in huge yield losses. Therefore, the present study was conducted to identify drought stress-responsive genes using next-generation (NGS) and third-generation sequencing (TGS) techniques. Five cDNA libraries were constructed from seedling leaf segments treated with a 30% solution of polyethylene glycol (PEG-6000) for 0, 1, 6, 12, and 48 h for second-generation sequencing. Leaf samples taken from upper third of sweet potato seedlings after 1, 6, 12, and 48 h of drought stress were used for the construction of cDNA libraries for third-generation sequencing; however, leaf samples from untreated plants were collected as controls. A total of 184,259,679 clean reads were obtained using second and third-generation sequencing and then assembled into 17,508 unigenes with an average length of 1,783 base pairs. Out of 17,508 unigenes, 642 (3.6%) unigenes failed to hit any homologs in any databases, which might be considered novel genes. A total of 2, 920, 1578, and 2,418 up-regulated unigenes and 3,834, 2,131, and 3,337 down-regulated unigenes from 1 h, 6 h, 12 h, and 48 h library were identified, respectively in drought stress versus control. In addition, after 6, 12, and 48 h of drought stress, 540 up-regulated unigenes, 486 down-regulated unigenes and 414 significantly differentially expressed unigenes were detected. It was found that several gene families including Basic Helix-loop-helix (bHLH), basic leucine zipper (bZIP), Cystein2/Histidine2 (C2H2), C3H, Ethylene-responsive transcription factor (ERF), Homo domain-leucine zipper (HD-ZIP), MYB, NAC (NAM, ATAF1/2, and CUC2), Thiol specific antioxidant and WRKY showed responses to drought stress. In total, 17,472 simple sequence repeats and 510,617 single nucleotide polymorphisms were identified based on transcriptome sequencing of the PFSP. About 96.55% of the obtained sequences are not available online in sweet potato genomics resources. Therefore, it will enrich annotated sweet potato gene sequences and enhance understanding of the mechanisms of drought tolerance through genetic manipulation. Moreover, it represents a sequence resource for genetic and genomic studies of sweet potato.
Spatially controlled nano-structuring of silicon with femtosecond vortex pulses
Authors: Rahimian M. G. , Jain A. , Larocque H. , Corkum P. B. , Karimi E. , Bhardwaj V. R. 
Published: July 2020

AbstractEngineering material properties is key for development of smart materials and next generation nanodevices. This requires nanoscale spatial precision and control to fabricate structures/defects. Lithographic techniques are widely used for nanostructuring in which a geometric pattern on a mask is transferred to a resist by photons or charged particles and subsequently engraved on the substrate. However, direct mask-less fabrication has only been possible with electron and ion beams. That is because light has an inherent disadvantage; the diffraction limit makes it difficult to interact with matter on dimensions smaller than the wavelength of light. Here we demonstrate spatially controlled formation of nanocones on a silicon surface with a positional precision of 50 nm using femtosecond laser ablation comprising a superposition of optical vector vortex and Gaussian beams. Such control and precision opens new opportunities for nano-printing of materials using techniques such as laser-induced forward transfer and in general broadens the scope of laser processing of materials.
Identification of novel molecular determinants of co-receptor usage in HIV-1 subtype F V3 envelope sequences
Authors: Distefano Maximiliano , Lanzarotti Esteban , Fernández María Florencia , Mangano Andrea , Martí Marcelo , Aulicino Paula 
Published: July 2020

AbstractHIV-1 determinants of coreceptor usage within the gp120 V3 loop have been broadly studied over the past years. This information has led to the development of state-of the-art bioinformatic tools that are useful to predict co-receptor usage based on the V3 loop sequence mainly of subtypes B, C and A. However, these methods show a poor performance for subtype F V3 loops, which are found in an increasing number of HIV-1 strains worldwide. In the present work we investigated determinants of viral tropisms in the understudied subtype F by looking at genotypic and structural information of coreceptor:V3 loop interactions in a novel group of 40 subtype F V3 loops obtained from HIV-1 strains phenotypically characterized either as syncytium inducing or non-syncytium inducing by the MT-2 assay. We provide novel information about estimated interactions energies between a set of V3 loops with known tropism in subtype F, that allowed us to improve predictions of the coreceptor usage for this subtype. Understanding genetic and structural features underlying HIV coreceptor usage across different subtypes is relevant for the rational design of preventive and therapeutic strategies aimed at limiting the HIV-1 epidemic worldwide.
Marine Os isotopic evidence for multiple volcanic episodes during Cretaceous Oceanic Anoxic Event 1b
Authors: Matsumoto Hironao , Kuroda Junichiro , Coccioni Rodolfo , Frontalini Fabrizio , Sakai Saburo , Ogawa Nanako O. , Ohkouchi Naohiko 
Published: July 2020

AbstractThe Aptian–Albian boundary is marked by one of the major oceanic perturbations during the Cretaceous, called Oceanic Anoxic Event (OAE) 1b. Extensive volcanic episodes at the Southern Kerguelen Plateau has been suggested as the trigger of OAE1b, but compelling evidence remains lacking. Here, we reconstructed the temporal variations of marine Os isotopic ratios across the Aptian–Albian boundary in the Tethyan and Pacific pelagic sedimentary records to elucidate the causal links between OAE1b, the biotic turnover, and volcanic episodes. Our new Os isotopic records show two negative spikes that correlate with a period of planktonic foraminiferal turnover across the Aptian–Albian boundary during OAE1b and suggest multiple submarine volcanic events. By comparing our Os isotopic profile with carbon isotopic compositions of carbonate, CaCO3content, and the relative abundances of agglutinated foraminifera, we conclude that ocean acidification caused by the massive release of CO2through extensive volcanic episodes could have promoted the major planktonic foraminiferal turnover during OAE1b.
Comparison of different automatic methods for the delineation of the total metabolic tumor volume in I–II stage Hodgkin Lymphoma
Authors: Martín-Saladich Queralt , Reynés-Llompart Gabriel , Sabaté-Llobera Aida , Palomar-Muñoz Azahara , Domingo-Domènech Eva , Cortés-Romera Montse 
Published: July 2020

AbstractTotal metabolic tumor volume (TMTV) is a promising quantitative biomarker for therapy assessment and prognosis in Hodgkin Lymphoma affected patients that allows prediction of patient outcome. The aim of this study was to evaluate the TMTV reproducibility between different sources of variability in tumor delimitation such as SUV-based thresholds (2.5, 41% and 50%) and software tools (Beth Israel plugin (BI) and LIFEx). Effect of contouring procedure both including single and multiple regions of interest was also studied in patients with multiple lesions, and optimal cut-offs for each studied method were displayed to compare the effect on prognosis. Strong alikeness in TMTV was found for 2.5 under software choice. Best accuracy in contouring compared to visual assessment of the disease was found for BI multiple ROI and LIFEx single ROI drawing. Similar cut-offs were found between both software for all considered thresholds, but best resemblance and highest cut-off due to an overestimation of the TMTV was found for 2.5 SUV. Our findings suggest that optimal reproducibility in TMTV is found for SUV > 2.5 threshold under choice of contouring methodology or software tool, meaning that overestimation of the TMTV threshold using 2.5 looks to be preferable than underestimation with 41% and 50%.
Identification of the novel bacterial blight resistance gene Xa46(t) by mapping and expression analysis of the rice mutant H120
Authors: Chen Shen , Wang Congying , Yang Jianyuan , Chen Bing , Wang Wenjuan , Su Jing , Feng Aiqing , Zeng Liexian , Zhu Xiaoyuan 
Published: July 2020

AbstractRice bacterial leaf blight is caused by Xanthomonas oryzae pv. oryzae (Xoo) and produces substantial losses in rice yields. Resistance breeding is an effective method for controlling bacterial leaf blight disease. The mutant line H120 derived from the japonica line Lijiangxintuanheigu is resistant to all Chinese Xoo races. To identify and map the Xoo resistance gene(s) of H120, we examined the association between phenotypic and genotypic variations in two F2 populations derived from crosses between H120/CO39 and H120/IR24. The segregation ratios of F2 progeny consisted with the action of a single dominant resistance gene, which we named Xa46(t). Xa46(t) was mapped between the markers RM26981 and RM26984 within an approximately 65.34-kb region on chromosome 11. The 12 genes predicted within the target region included two candidate genes encoding the serine/threonine-protein kinase Doa (Loc_Os11g37540) and Calmodulin-2/3/5 (Loc_Os11g37550). Differential expression of H120 was analyzed by RNA-seq. Four genes in the Xa46(t) target region were differentially expressed after inoculation with Xoo. Mapping and expression data suggest that Loc_Os11g37540 allele is most likely to be Xa46(t). The sequence comparison of Xa23 allele between H120 and CBB23 indicated that the Xa46(t) gene is not identical to Xa23.