bluuebunny/crossref_metadata_2025_split huggingface dataset:
Population genetics of ectoparasitic mitesVarroaspp. in Eastern and Western honey bees
Authors: Dietemann Vincent , Beaurepaire Alexis , Page Paul , Yañez Orlando , Buawangpong Ninat , Chantawannakul Panuwan , Neumann Peter 
Published: July 2019

AbstractHost shifts of parasites are often causing devastating effects in the new hosts. TheVarroagenus is known for a lineage ofVarroa destructorthat shifted to the Western honey bee,Apis mellifera, with disastrous effects on wild populations and the beekeeping industry. Despite this, the biology ofVarroaspp. remains poorly understood in its native distribution range, where it naturally parasitizes the Eastern honey bee,Apis cerana. Here, we combined mitochondrial and nuclear DNA analyses with the assessment of mite reproduction to determine the population structure and host specificity ofV. destructorandVarroa jacobsoniiin Thailand, where both hosts and severalVarroaspecies and haplotypes are sympatric. Our data confirm previously described mite haplogroups, and show three novel haplotypes. Multiple infestations of single host colonies by both mite species and introgression of alleles betweenV. destructorandV. jacobsoniisuggest that hybridization occurs between the two species. Our results indicate that host specificity and population genetic structure in the genusVarroais more labile than previously thought. The ability of the host shiftedV. destructorhaplotype to spillback toA. ceranaand to hybridize withV. jacobsoniicould threaten honey bee populations of Asia and beyond.
Primitive Helium Is Sourced From Seismically Slow Regions in the Lowermost Mantle
Authors: Williams C. D. , Mukhopadhyay S. , Rudolph M. L. , Romanowicz B. 
Published: July 2019

AbstractA major goal in Earth Science has been to understand how geochemical characteristics of lavas at the Earth's surface relate to the location and formation history of specific regions in the Earth's interior. For example, some of the strongest evidence for the preservation of primitive material comes from low 4He/3He ratios in ocean island basalts, but the location of the primitive helium reservoir(s) remains unknown. Here we combine whole‐mantle seismic tomography, simulations of mantle flow, and a global compilation of new and existing measurements of the 4He/3He ratios in ocean island basalts to constrain the source location of primitive 4He/3He material. Our geodynamic simulations predict the present‐day surface expression of plumes to be laterally offset from their lower mantle source locations. When this lateral offset is accounted for, a strong relationship emerges between minimum 4He/3He ratios in oceanic basalts and seismically slow regions, which are generally located within the two large low shear‐wave velocity provinces (LLSVPs). Conversely, no significant relationship is observed between maximum 208Pb*/206Pb* ratios and seismically slow regions in the lowermost mantle. These results indicate that primitive materials are geographically restricted to LLSVPs, while recycled materials are more broadly distributed across the lower mantle. The primitive nature of the LLSVPs indicates these regions are not composed entirely of recycled slabs, while complementary xenon and tungsten isotopic anomalies require the primitive portion of the LLSVPs to have formed during Earth's accretion, survived the Moon‐forming giant impact, and remained relatively unmixed during the subsequent 4.5 billion years of mantle convection.
Spatially Resolved Neutral Wind Response Times During High Geomagnetic Activity Above Svalbard
Authors: Billett D. D. , Wild J. A. , Grocott A. , Aruliah A. L. , Ronksley A. M. , Walach M.‐T. , Lester M. 
Published: July 2019

AbstractIt has previously been shown that in the high‐latitude thermosphere, sudden changes in plasma velocity (such as those due to changes in interplanetary magnetic field) are not immediately propagated into the neutral gas via the ion‐drag force. This is due to the neutral particles (O, O2, and N2) constituting the bulk mass of the thermospheric altitude range and thus holding on to residual inertia from a previous level of geomagnetic forcing. This means that consistent forcing (or dragging) from the ionospheric plasma is required, over a period of time, long enough for the neutrals to reach an equilibrium with regard to ion drag. Furthermore, mesoscale variations in the plasma convection morphology, solar pressure gradients, and other forces indicate that the thermosphere‐ionosphere coupling mechanism will also vary in strength across small spatial scales. Using data from the Super Dual Auroral Radar Network and a Scanning Doppler Imager, a geomagnetically active event was identified, which showed plasma flows clearly imparting momentum to the neutrals. A cross‐correlation analysis determined that the average time for the neutral winds to accelerate fully into the direction of ion drag was 75 min, but crucially, this time varied by up to 30 min (between 67 and 97 min) within a 1,000‐km field of view at an altitude of around 250 km. It is clear from this that the mesoscale structure of both the plasma and neutrals has a significant effect on ion‐neutral coupling strength and thus energy transfer in the thermosphere.
Kinetic Analysis of the Energy Transport of Two‐Flow Components in the Plasma Sheet
Authors: Cao Jin‐Bin , Ren Ganming , Ma Yuduan 
Published: July 2019

AbstractSatellite observations indicate that multiple components often exist in the plasma sheet, particularly during impulsive fast flow events. In this paper, we perform a kinetic analysis of the energy transport of plasma sheet ion flow using a model of two‐component plasma sheet ion flows (Background convection flow represented by subscript “b” and Fast flow represented by subscript “f”) and compare the energy transport calculated by kinetic approach Qk with those obtained from magnetohydrodynamic (MHD) approach QMHD. The ratio of Qk/QMHD is always larger than unity and is positively proportional to the ratios of Vf/Vb and Tf/Tb. The maximum values of Qk/QMHD occur in the low‐speed ranges (i.e., small density ratio Nf/N). When Nf/N exceeds 0.4, the ratio of Qk/QMHD is almost the same for a wide parameter ranges of Vf, Tf, and Vb. Heat flux is important in low‐speed range and is neglectable in the high‐speed range. The adiabatic polytropic index 5/3 cannot correctly describe energy transport rate. A density ratio Nf/N of 0.3% of high‐speed ion flow can make the effective polytropic index obviously deviate from adiabatic polytropic index (5/3). The above theoretic results can well explain previously reported satellite in situ observations.
The Comparison of Lunar Tidal Characteristics in the Low‐Latitudinal Ionosphere Between East Asian and American Sectors During Stratospheric Sudden Warming Events: 2009–2018
Authors: Liu J. , Zhang D.‐H. , Hao Y.‐Q. , Xiao Z. 
Published: July 2019

AbstractLongitudinal differences of low‐latitudinal ionospheric responses during five major, four minor, and a none‐stratospheric sudden warming (SSW) winters from 2009 to 2018 between East Asian and American sectors are studied with total electron content (TEC). The time‐shifted semidiurnal (TS) pattern and the amplitude (AM2), phase angle (PAM2), and relative strength (RSM2) of the lunar semidiurnal tide (M2) harmonic in TEC are compared between the two sectors. Main results are as follows: (1) TS patterns, AM2,and RSM2 tend to be more discernable or larger in the American sector than in the East Asian sector. (2) TS patterns and PAM2 correspond well with the moon phase, and the occurrence of TS patterns coincides well with the enhancement of AM2 and RSM2. (3) Such patterns sometimes occur before the polar peak warming and experience several cycles during one event, but the most significant one tends to follow the peak warming. These characteristics are most distinct during major events with low solar activities. Our results support the mechanism that TS patterns in low‐latitudinal ionosphere parameters are due to enhanced lunitidal effects on the E region dynamo. Besides, changes in temperature and wind during SSWs can also contribute to the generation of TS signatures. Longitudinal differences in TEC suggest that the M2 influence on the low‐latitudinal ionosphere tends to be more prominent in the American sector than in the East Asian sector during SSWs. These differences probably result from a combined effect of the longitudinal variety in atmospheric (especially tidal) and electrodynamic processes.
Imaging Upper‐Mantle Structure Under USArray Using Long‐Period Reflection Seismology
Authors: Shearer Peter M. , Buehler Janine 
Published: July 2019

AbstractTopside reverberations off mantle discontinuities are commonly observed at long periods, but their interpretation is complicated because they include both near‐source and near‐receiver reflections. We have developed a method to isolate the stationside reflectors in large data sets with many sources and receivers. Analysis of USArray transverse‐component data from 3,200 earthquakes, using direct S as a reference phase, shows clear reflections off the 410‐ and 660‐km discontinuities, which can be used to map the depth and brightness of these features. Because our results are sensitive to the impedance contrast (velocity and density), they provide a useful complement to receiver‐function studies, which are primarily sensitive to the S velocity jump alone. In addition, reflectors in our images are more spread out in time than in receiver functions, providing good depth resolution. Our images show strong discontinuities near 410 and 660 km across the entire USArray footprint, with intriguing reflectors at shallower depths in many regions. Overall, the discontinuities in the east appear simpler and more monotonous with a uniform transition zone thickness of 250 km compared to the western United States. In the west, we observe more complex discontinuity topography and small‐scale changes below the Great Basin and the Rocky Mountains, and a decrease in transition‐zone thickness along the western coast. We also observe a dipping reflector in the west that aligns with the top of the high‐velocity Farallon slab anomaly seen in some tomography models, but which also may be an artifact caused by near‐surface scattering of incoming S waves.
Revisiting Intraslab Earthquakes Beneath Kyushu, Japan: Effect of Ridge Subduction on Seismogenesis
Authors: Nakajima Junichi 
Published: July 2019

AbstractThis study investigates intraslab seismicity of the Philippine Sea Plate beneath Kyushu, Japan, where the Kyushu‐Palau Ridge (KPR) is being subducted and the age of the incoming plate varies across the ridge. Intraslab earthquakes at depths of 30–270 km are first relocated, and focal mechanism solutions of 181 earthquakes are determined. The relocated hypocenters show marked along‐arc variations in their depth limits and distributions. The geometry of the slab Moho is delineated by considering observed focal mechanisms, precisely relocated hypocenters, and the depth extent of the hydrated slab crust previously estimated by receiver function analysis. Intraslab earthquakes are classified into crustal and mantle earthquakes based on the inferred Moho geometry. The number of crustal earthquakes decreases monotonically with depth, and little seismicity occurs beyond 100‐km depth, but mantle earthquakes become increasingly active with increasing depth and reach a peak at a depth of ~150 km. An area of locally thickened crustal seismicity (up to 12 km thick) in offshore central Kyushu corresponds to the subducted KPR, suggesting that the KPR influences crustal seismicity to a depth of at least ~60 km. The double seismic zone is clearly observed at depths of 80–150 km in southern Kyushu, where the old Philippine Sea Plate has continued to subduct over at least >5 Myr. Our observations suggest that the genesis of intraslab earthquakes is locally affected by the subduction of the KPR and regionally governed by the along‐arc variation in the formation age of the incoming plate.
Inferring Crustal Temperatures Beneath Italy From Joint Inversion of Receiver Functions and Surface Waves
Authors: Diaferia G. , Cammarano F. , Piana Agostinetti N. , Gao C. , Lekic V. , Molinari I. , Boschi L. 
Published: July 2019

AbstractTemperature distribution at depth is of key importance for characterizing the crust, defining its mechanical behavior and deformation. Temperature can be retrieved by heat flow measurements in boreholes that are sparse, shallow, and have limited reliability, especially in active and recently active areas. Laboratory data and thermodynamic modeling demonstrate that temperature exerts a strong control on the seismic properties of rocks, supporting the hypothesis that seismic data can be used to constrain the crustal thermal structure. We use Rayleigh wave dispersion curves and receiver functions, jointly inverted with a transdimensional Monte Carlo Markov Chain algorithm, to retrieve the VS and VP/VS within the crust in the Italian peninsula. The high values (>1.9) of VP/VS suggest the presence of filled‐fluid cracks in the middle and lower crust. Intracrustal discontinuities associated with large values of VP/VS are interpreted as the α−β quartz transition and used to estimate geothermal gradients. These are in agreement with the temperatures inferred from shear wave velocities and exhibit a behavior consistent with the known tectonic and geodynamic setting of the Italian peninsula. We argue that such methods, based on seismological observables, provide a viable alternative to heat flow measurements for inferring crustal thermal structure.
Distribution, Occurrence, and Fate of Biogenic Dimethylated Sulfur Compounds in the Yellow Sea and Bohai Sea During Spring
Authors: Xu Feng , Jin Na , Ma Zhun , Zhang Hong‐Hai , Yang Gui‐Peng 
Published: July 2019

AbstractThe spatial distributions of biogenic dimethylated sulfur compounds (BDSCs), including dimethylsulfide (DMS), dimethylsulfoniopropionate (DMSP), and dimethylsulfoxide, were determined in the Yellow Sea and Bohai Sea during a survey in April–May 2014 and the occurrence and fate of BDSCs in the surface seawater were investigated. The concentrations of DMS and DMSP were significantly correlated with the stocks of chlorophyll a and a decreasing trend was observed from the inshore to the offshore areas. In situ incubation experiments indicated that more than half of the degraded dissolved DMSP (DMSPd) was transformed into DMS. Irradiation experiments showed that the photooxidation of DMS under ultraviolet B, ultraviolet A, and visible light accounted for 23.9%, 71.8%, and 4.3% of the total photooxidation of DMS, respectively. The sea‐to‐air fluxes of DMS ranged from 0.24 to 34.11 μmol m−2 day−1 with a mean of 8.84 μmol m−2 day−1. A comparison of the DMS production rate and main removal rates indicated that bioproduction cannot completely maintain the removal of DMS and might not be the only but the primary source of DMS in the surface seawater. Additionally, the average turnover times of microbial consumption, photooxidation, and sea‐to‐air exchange of DMS were 1.53, 1.16, and 4.28 day and the contributions of the three removal pathways were 40.0%, 41.2%, and 18.8% respectively; this indicated that microbial consumption and photooxidation played dominant roles in controlling the removal of DMS from the surface seawater.
Neutralizing monoclonal antibody against Dickkopf2 impairs lung cancer progression via activating NK cells
Authors: Shen Tianli , Chen Zhengxi , Qiao Ju , Sun Xuejun , Xiao Qian 
Published: July 2019

AbstractAdenomatous polyposis coli (APC) and KRAS proto-oncogene (KRAS) mutations frequently co-occur in non-small cell lung cancer. Inactivating APC mutations in colorectal carcinoma has been well characterized, leading to the approaches targeting on dysregulated APC pathway. However, it remains undetermined whether such approaches are also applicable to non-small cell lung cancer patients harboring similar mutations of APC. Dickkopf-related protein 2 (DKK2) is a Wnt antagonist. Our previous study has proved that anti-DKK2 antibody 5F8 suppressed the growth of colorectal carcinoma with APC mutations, illustrating a new target agent of APC-mutated tumors. This study aimed to investigate the potential of applying anti-DKK2 antibody to non-small cell lung cancer with APC mutations. We found significant upregulation of Dkk2 expression in APC-mutated lung cancers. Administration of DKK2 antibody inhibited cancer growth via modulating tumor immune microenvironment in lung cancer mouse models. Our study provided strong evidence supporting APC mutations-directed applications of anti-DKK2 targeted therapy in a wide range of cancer types, including lung cancer.
Reassessing the projections of the World Water Development Report
Authors: Boretti Alberto , Rosa Lorenzo 
Published: July 2019

AbstractThe 2018 edition of the United Nations World Water Development Report stated that nearly 6 billion peoples will suffer from clean water scarcity by 2050. This is the result of increasing demand for water, reduction of water resources, and increasing pollution of water, driven by dramatic population and economic growth. It is suggested that this number may be an underestimation, and scarcity of clean water by 2050 may be worse as the effects of the three drivers of water scarcity, as well as of unequal growth, accessibility and needs, are underrated. While the report promotes the spontaneous adoption of nature-based-solutions within an unconstrained population and economic expansion, there is an urgent need to regulate demography and economy, while enforcing clear rules to limit pollution, preserve aquifers and save water, equally applying everywhere. The aim of this paper is to highlight the inter-linkage in between population and economic growth and water demand, resources and pollution, that ultimately drive water scarcity, and the relevance of these aspects in local, rather than global, perspective, with a view to stimulating debate.
Clonal Evolution and Changes in Two AML Patients Detected with A Novel Single-Cell DNA Sequencing Platform
Authors: Xu Liwen , Durruthy-Durruthy Robert , Eastburn Dennis J. , Pellegrino Maurizio , Shah Omid , Meyer Everett , Zehnder James 
Published: July 2019

AbstractNext-generation sequencing (NGS) is used to detect gene variants in genetically complex cell populations of cancer patient samples. Traditional bulk analysis can only provide average variant allele frequencies of the targeted genes across all sampled cells. It fails to resolve mutational co-occurrences and may miss rare cancer cells. Genome analysis at the single cell level offers the opportunity to more fully resolve clonal architecture. Peripheral blood mononuclear cells were sampled from acute myeloid leukemia patients longitudinally and single-cell DNA sequencing libraries were generated with a novel droplet-based microfluidics approach. Molecular profiling of single nucleotide variants across thousands of cells revealed genetic chimerism in patients after bone marrow transplantation (BMT). Importantly, hierarchical clustering analysis of single nucleotide variants (SNVs) uncovered a distinct oncogenic clone of cells carrying mutated tumor-suppressor and/or oncogene(s). This novel single-cell DNA sequencing approach enabled precise monitoring of engraftment and revealed clonal evolution of oncogenic cells during the progression and treatment of the disease.
SQSTM1/p62 loss reverses the inhibitory effect of sunitinib on autophagy independent of AMPK signaling
Authors: Hou Bolin , Wang Gang , Gao Quan , Wei Yanjie , Zhang Caining , Wang Yange , Huo Yuqing , Yang Huaiyi , Jiang Xuejun , Xi Zhijun 
Published: July 2019

AbstractSunitinib (ST), a multitargeted receptor tyrosine kinase inhibitor, has been demonstrated to be effective for the treatment of renal carcinoma. It has been reported that ST is involved in the mediation of autophagy; however, its regulatory role in the autophagic process remains controversial. Furthermore, the mechanism by which activated AMP-activated protein kinase (AMPK) negatively regulates autophagy remains nearly unexplored. In the present study, we revealed that ST inhibited AMPK activity and regulated autophagy in a cell type- and dose-dependent manner. In a number of cell lines, ST was demonstrated to inhibit H2O2-induced autophagy and the phosphorylation of acetyl-CoA carboxylase (ACC), whereas alone it could block the autophagic flux concurrent with increased expression of p62. An immunoprecipitation assay revealed that LC3 directly interacted with p62, whereas ST increased punctate LC3 staining, which was well colocalized with p62. Taken together, we reveal a previously unnoticed pathway for ST to regulate the autophagic process, and p62, although often utilized as a substrate in autophagy, plays a critical role in regulating the inhibition of ST in both basal and induced autophagy.
Porous ionic liquid polymer: A reusable adsorbent with broad operating pH range for speciation of nitrate and nitrite
Authors: Nayebi Reyhaneh , Daneshvar Tarigh Ghazale , Shemirani Farzaneh 
Published: July 2019

AbstractIonic liquids (ILs) are a class of fluids with unique physicochemical properties employing polymeric substances emerging new materials. Solidification of ILs into porous materials generates porous ionic liquid polymers that combine the unique characteristics of ILs with common porous materials and polymers. In this study, it’s the first time the porous ionic liquid polymer was chosen as a sorbent for extraction and speciation of nitrite and nitrate. Porous IL was prepared through polymerization of 1-allyl-3-methylimidazolium bromide monomers in the presence of azobisisobutyronitrile (AIBN) and crosslinking of ethylene glycol dimethyl acrylate (EGDMA). Parameters affecting the adsorbent performance were optimized. Under the optimal conditions, correlation coefficient (R2) was 0.9996 and LOD was 0.1 µg L−1. This method presented the linearity in the concentration range between 0.1–100 µg L−1 and the relative standard deviation was 3.2%. Finally, the adsorption behavior of the obtained sorbent for nitrate and nitrite determination in various real samples was evaluated. The result indicates that the porous ionic liquid polymer showed high adsorption capacity (233 mg g−1). The convenient preparation of the porous ionic liquid material, as well as high adsorption capacity for anionic pollutants predicted its broad application potential in anion removal materials.
Anatomy and evolution of the first Coleoidea in the Carboniferous
Authors: Klug Christian , Landman Neil H. , Fuchs Dirk , Mapes Royal H. , Pohle Alexander , Guériau Pierre , Reguer Solenn , Hoffmann René 
Published: July 2019

AbstractColeoidea (squids and octopuses) comprise all crown group cephalopods except the Nautilida. Coleoids are characterized by internal shell (endocochleate), ink sac and arm hooks, while nautilids lack an ink sac, arm hooks, suckers, and have an external conch (ectocochleate). Differentiating between straight conical conchs (orthocones) of Palaeozoic Coleoidea and other ectocochleates is only possible when rostrum (shell covering the chambered phragmocone) and body chamber are preserved. Here, we provide information on how this internalization might have evolved. We re-examined one of the oldest coleoids,Gordoniconus beargulchensisfrom the Early Carboniferous of the Bear Gulch Fossil-Lagerstätte (Montana) by synchrotron, various lights and Reflectance Transformation Imaging (RTI). This revealed previously unappreciated anatomical details, on which we base evolutionary scenarios of how the internalization and other evolutionary steps in early coleoid evolution proceeded. We suggest that conch internalization happened rather suddenly including early growth stages while the ink sac evolved slightly later.