bluuebunny/crossref_metadata_2025_split huggingface dataset:
Atmospheric Gravity Waves in the Ionosphere and Thermosphere During the 2017 Solar Eclipse
Authors: Lin Cissi Y. , Deng Yue , Ridley Aaron 
Published: April 2018

AbstractAs a cavity of solar radiation created by the lunar shadow moves across the United States on 21 August 2017, decreases in local ionospheric and thermospheric (IT) temperature and density are anticipated. The average velocity of the total solar eclipse across the United States is ~700 m/s. The supersonically moving lunar shadow has induced bow waves and gravity waves that are observed by the Global Navigation Satellite System (GNSS) network. We use the Global Ionosphere‐Thermosphere Model, a global circulation model solving for nonhydrostatic equations, with high‐resolution (2° in longitude and 0.5° in latitude) and high‐cadence (forcing updated every 2 s) settings to investigate the IT responses related to the atmospheric gravity wave perturbations during the solar eclipse. The modeled IT conditions extracted at 5‐s cadence at two ground stations reveal different responses in both neutral and electron densities under totality and partial‐eclipse scenarios. A bow wave of −0.2 TECu develops and lasts hours since totality, which is comparable with the GNSS observations. Gravity waves with period of 20–30 min observed by GNSS have been reproduced in our simulations.
Characterization of the Extraterrestrial Magnesium Source in the Atmosphere Using a Meteoric Ablation Simulator
Authors: Bones D. L. , Gómez Martín J. C. , Carrillo Sánchez J. D. , Dobson A. J. , Plane J. M. C. 
Published: April 2018

AbstractAblation of Mg from meteoroids entering the Earth's atmosphere was studied experimentally using a Meteoric Ablation Simulator: micron‐sized particles of representative meteoritic material were flash heated to simulate atmospheric entry and the ablation rate of Mg with respect to Na measured by fast time‐resolved laser‐induced fluorescence. Over the range of particle diameters and entry velocities studied, Mg ablates 4.3 ± 2.1 times less efficiently than Na and 2.4 ± 0.8 times less efficiently than Fe. The resulting evaporation profiles indicate that Mg mostly ablates around 84 km in the atmosphere, compared with Fe at 88 km and Na at 95 km. The chemical ablation model Chemical Ablation Model predicts satisfactorily the measured peak ablation altitudes and relative ablated fractions of Mg, Na, Fe, and Ca but does not capture the breadth of the ablation profiles, probably due to the inhomogeneity of the minerals present in meteoroids combined with experimental limitations.
Investigation of Martian Magnetic Topology Response to 2017 September ICME
Authors: Xu Shaosui , Fang Xiaohua , Mitchell David L. , Ma Yingjuan , Luhmann Janet G. , DiBraccio Gina A. , Weber Tristan , Brain David , Mazelle Christian , Curry Shannon M. , Lee Christina O. 
Published: April 2018

AbstractMany aspects of the Sun‐Mars interaction have been investigated during solar transient events with measurements from multiple spacecrafts and also simulation efforts. Limited discussion has been paid to magnetic topology response to disturbed upstream conditions. The implications of topology changes include, but are not limited to, the pattern of energetic particle precipitation into the Martian atmosphere and the impact on cold ion escape during solar transient events as low‐energy ion escape is dependent on magnetic topology. In this study, we investigate the magnetic topology response to the 2017 September interplanetary coronal mass ejection (ICME) event with measurements collected by the Mars Atmospheric and Volatile EvolutioN spacecraft. It is found that the interface between draped interplanetary magnetic field and closed field lines was moved from 800–1400 km in altitude during quiet conditions to 200–400 km after ICME arrived at Mars and then relaxed back to high altitudes again after the event. To gain insight into magnetic topology response on a global scale, we first validate magnetic topology from a time‐dependent simulation with a single‐fluid multispecies magnetohydrodynamic (MHD) model by comparing magnetic topology determined from Mars Atmospheric and Volatile EvolutioN data, which shows a good agreement. Then we present MHD predictions of global magnetic topology changes during this ICME event. In addition to a deeper interplanetary magnetic field penetration, MHD results suggest more open field lines in response to the ICME event.
Melting Inside the Tibetan Crust? Constraint From Electrical Conductivity of Peraluminous Granitic Melt
Authors: Guo Xuan , Zhang Li , Su Xue , Mao Zhu , Gao Xiao‐Ying , Yang Xiaozhi , Ni Huaiwei 
Published: April 2018

AbstractMagnetotelluric and seismological studies suggested the presence of partial melts in the middle to lower Himalaya‐Tibetan crust. However, the melt fractions inferred by previous work were based on presumed electrical conductivity of melts. We performed measurements on the electrical conductivity of peraluminous granitic melts with 0.16–8.4 wt % H2O (the expected compositions in the Tibetan crust) at 600–1,300°C and 0.5–1.0 GPa. Peraluminous melt exhibits lower electrical conductivity than peralkaline melt at dry condition, but this difference diminishes at H2O > 2 wt %. With our data, the observed electrical anomalies in the Tibetan crust could be explained by 2–33 vol % of peraluminous granitic melts with H2O > 6 wt %. Possible reasons for our inferred melt fractions being higher than seismological constraints include the following: (1) The real melts are more Na and H2O rich, (2) the effect of melt reducing seismic velocities was overestimated, and (3) the anomalies at some locations are due to fluids.
Assessment of Hydraulic Connectivity of Fractures in Mudstones by Single‐Borehole Investigations
Authors: Ishii Eiichi 
Published: April 2018

AbstractAssessing the hydraulic connectivity of fractures by single‐borehole investigations is crucial to radioactive waste disposal but is still a challenge as such connectivity is difficult to measure directly. This study presents geological, hydrological, hydrochemical, and rock‐mechanical data for three faulted/fractured mudstones (the Koetoi, Wakkanai, and Palfris Formations) and proposes a new methodology for assessing the hydraulic connectivity of fractures. The methodology consists of three steps: (a) dividing the formation into two domains with a ductility index (DI) of >2 and <2 (DI is defined as the effective mean stress normalized to the tensile strength of intact rock), (b) estimating the hydraulic connectivity of fractures by analyzing pressure change obtained by packer tests and geological interpretation, and (c) verifying the estimation using pore pressure and water chemistry/geochemistry. The first step is necessary because the failure mode of damage‐zone fractures in fault zones can differ between the DI > 2 and DI < 2 domains, which may lead to significant differences in the hydraulic connectivity of fractures. During the second step, potential domains in which the hydraulic connectivity of fractures is limited are identified where upward trends, characterized by slopes of ∼0.5–1.0, are observed during the middle to late period of elapsed time on log‐log plots of pressure derivatives. Although the third step can be performed in various ways, this study employs the observation of pressure anomalies and the detection of young external water. Analyses of the three formations demonstrate the applicability and reliability of the proposed methodology.
TRPM2: a candidate therapeutic target for treating neurological diseases
Authors: Belrose Jillian Corinne , Jackson Michael Frederick 
Published: April 2018

AbstractTransient receptor potential melastatin 2 (TRPM2) is a calcium (Ca2+)-permeable non-selective cation channel belonging to the TRP ion channel family. Oxidative stress-induced TRPM2 activation provokes aberrant intracellular Ca2+ accumulation and cell death in a variety of cell types, including neurons. Aberrant TRPM2 function has been implicated in several neurological disorders including ischemia/stroke, Alzheimer's disease, neuropathic pain, Parkinson's disease and bipolar disorder. In addition to research identifying a role for TRPM2 in disease, progress has been made in the identification of physiological functions of TRPM2 in the brain, including recent evidence that TRPM2 is necessary for the induction of N-methyl-D-aspartate (NMDA) receptor-dependent long-term depression, an important form of synaptic plasticity at glutamate synapses. Here, we summarize recent evidence on the role of TRPM2 in the central nervous system (CNS) in health and disease and discuss the potential therapeutic implications of targeting TRPM2. Collectively, these studies suggest that TRPM2 represents a prospective novel therapeutic target for neurological disorders.
Upregulation of SALL4 by EGFR activation regulates the stemness of CD44-positive lung cancer
Authors: Du Wenjing , Ni Lan , Liu Baojun , Wei Ying , Lv Yubao , Qiang Sujing , Dong Jingcheng , Liu Xijun 
Published: April 2018

AbstractThe transcriptional factor SALL4, an important stem cell regulator, is expressed in hematopoietic stem cells and various malignancies, but its role in EGFR-mutated NSCLCs has not been studied yet. Here, we report that the expression of Sal-like protein 4 (SALL4), was significantly higher in EGFR mutated lung tumors than in non-tumor tissue. SALL4-high lung cancer patients had poorer prognosis after surgery than SALL4-low patients. The expression of SALL4 could be induced by the activation of EGFR through the extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathway. The knockdown of SALL4 expression could suppress spheroid formation and the expression of lung cancer stem cell marker CD44. More interestingly, the knockdown of SALL4 expression could suppress the migration, invasion, and metastasis of the lung cancer cells and significantly increase the sensitivity of EGFR mutated cells to Erlotinib. These results suggest that SALL4 may be a novel potential therapeutic target for the diagnosis and treatment of lung cancer.
Structural basis for GPR40 allosteric agonism and incretin stimulation
Authors: Ho Joseph D. , Chau Betty , Rodgers Logan , Lu Frances , Wilbur Kelly L. , Otto Keith A. , Chen Yanyun , Song Min , Riley Jonathan P. , Yang Hsiu-Chiung , Reynolds Nichole A. , Kahl Steven D. , Lewis Anjana Patel , Groshong Christopher , Madsen Russell E. , Conners Kris , Lineswala Jayana P. , Gheyi Tarun , Saflor Melbert-Brian Decipulo , Lee Matthew R. , Benach Jordi , Baker Kenton A. , Montrose-Rafizadeh Chahrzad , Genin Michael J. , Miller Anne R. , Hamdouchi Chafiq 
Published: April 2018

AbstractActivation of free fatty acid receptor 1 (GPR40) by synthetic partial and full agonists occur via distinct allosteric sites. A crystal structure of GPR40-TAK-875 complex revealed the allosteric site for the partial agonist. Here we report the 2.76-Å crystal structure of human GPR40 in complex with a synthetic full agonist, compound 1, bound to the second allosteric site. Unlike TAK-875, which acts as a Gαq-coupled partial agonist, compound 1 is a dual Gαq and Gαs-coupled full agonist. compound 1 binds in the lipid-rich region of the receptor near intracellular loop 2 (ICL2), in which the stabilization of ICL2 by the ligand is likely the primary mechanism for the enhanced G protein activities. The endogenous free fatty acid (FFA), γ-linolenic acid, can be computationally modeled in this site. Both γ-linolenic acid and compound 1 exhibit positive cooperativity with TAK-875, suggesting that this site could also serve as a FFA binding site.
Regulation of Yki/Yap subcellular localization and Hpo signaling by a nuclear kinase PRP4K
Authors: Cho Yong suk , Zhu Jian , Li Shuangxi , Wang Bing , Han Yuhong , Jiang Jin 
Published: April 2018

AbstractHippo (Hpo) signaling pathway controls tissue growth by regulating the subcellular localization of Yorkie (Yki)/Yap via a cytoplasmic kinase cassette containing an upstream kinase Hpo/MST1/2 and a downstream kinase Warts (Wts)/Lats1/2. Here we show that PRP4K, a kinase involved in mRNA splicing, phosphorylates Yki/Yap in the nucleus to prevent its nuclear accumulation and restrict Hpo pathway target gene expression. PRP4K inactivation accelerates whereas excessive PRP4K inhibits Yki-driven tissue overgrowth. PRP4K phosphorylates a subset of Wts/Lats1/2 sites on Yki/Yap to inhibit the binding of Yki/Yap to the Scalloped (Sd)/TEAD transcription factor and exclude Yki/Yap nuclear localization depending on nuclear export. Furthermore, PRP4K inhibits proliferation and invasiveness of cultured breast cancer cells and its high expression correlates with good prognosis in breast cancer patients. Our study unravels an unanticipated layer of Hpo pathway regulation and suggests that PRP4K-mediated Yki/Yap phosphorylation in the nucleus provides a fail-safe mechanism to restrict aberrant pathway activation.
Long-term viability and function of transplanted islets macroencapsulated at high density are achieved by enhanced oxygen supply
Authors: Evron Yoav , Colton Clark K. , Ludwig Barbara , Weir Gordon C. , Zimermann Baruch , Maimon Shiri , Neufeld Tova , Shalev Nurit , Goldman Tali , Leon Assaf , Yavriyants Karina , Shabtay Noa , Rozenshtein Tania , Azarov Dimitri , DiIenno Amanda R. , Steffen Anja , de Vos Paul , Bornstein Stefan R. , Barkai Uriel , Rotem Avi 
Published: April 2018

AbstractTransplantation of encapsulated islets can cure diabetes without immunosuppression, but oxygen supply limitations can cause failure. We investigated a retrievable macroencapsulation device wherein islets are encapsulated in a planar alginate slab and supplied with exogenous oxygen from a replenishable gas chamber. Translation to clinically-useful devices entails reduction of device size by increasing islet surface density, which requires increased gas chamber pO2. Here we show that islet surface density can be substantially increased safely by increasing gas chamber pO2 to a supraphysiological level that maintains all islets viable and functional. These levels were determined from measurements of pO2 profiles in islet-alginate slabs. Encapsulated islets implanted with surface density as high as 4,800 islet equivalents/cm3 in diabetic rats maintained normoglycemia for more than 7 months and provided near-normal intravenous glucose tolerance tests. Nearly 90% of the original viable tissue was recovered after device explantation. Damaged islets failed after progressively shorter times. The required values of gas chamber pO2 were predictable from a mathematical model of oxygen consumption and diffusion in the device. These results demonstrate feasibility of developing retrievable macroencapsulated devices small enough for clinical use and provide a firm basis for design of devices for testing in large animals and humans.
Analysis of Optimal Sequential State Discrimination for Linearly Independent Pure Quantum States
Authors: Namkung Min , Kwon Younghun 
Published: April 2018

AbstractRecently, J. A. Bergou et al. proposed sequential state discrimination as a new quantum state discrimination scheme. In the scheme, by the successful sequential discrimination of a qubit state, receivers Bob and Charlie can share the information of the qubit prepared by a sender Alice. A merit of the scheme is that a quantum channel is established between Bob and Charlie, but a classical communication is not allowed. In this report, we present a method for extending the original sequential state discrimination of two qubit states to a scheme of N linearly independent pure quantum states. Specifically, we obtain the conditions for the sequential state discrimination of N = 3 pure quantum states. We can analytically provide conditions when there is a special symmetry among N = 3 linearly independent pure quantum states. Additionally, we show that the scenario proposed in this study can be applied to quantum key distribution. Furthermore, we show that the sequential state discrimination of three qutrit states performs better than the strategy of probabilistic quantum cloning.
Critical roles of TRPV2 channels, histamine H1 and adenosine A1 receptors in the initiation of acupoint signals for acupuncture analgesia
Authors: Huang Meng , Wang Xuezhi , Xing Beibei , Yang Hongwei , Sa Zheyan , Zhang Di , Yao Wei , Yin Na , Xia Ying , Ding Guanghong 
Published: April 2018

AbstractAcupuncture is one of the most promising modalities in complimentary medicine. However, the underlying mechanisms are not well understood yet. We found that in TRPV2 knockout male mice, acupuncture-induced analgesia was suppressed with a decreased activation of mast cells in the acupoints stimulated. The mast cell stabilizer sodium cromolyn could suppress the release of adenosine in the acupoints on male rats. A direct injection of adenosine A1 receptor agonist or histamine H1 receptor agonist increased β-endorphin in the cerebral-spinal fluid in the acute adjuvant arthritis male rats and thus replicated the analgesic effect of acupuncture. These observations suggest that the mast cell is the central structure of acupoints and is activated by acupuncture through TRPV2 channels. The mast cell transduces the mechanical stimuli to acupuncture signal by activating either H1 or A1 receptors, therefore triggering the acupuncture effect in the subject. These findings might open new frontiers for acupuncture research.
Ridge-furrow with plastic film and straw mulch increases water availability and wheat production on the Loess Plateau
Authors: Liu Gaoyuan , Zuo Yuhuan , Zhang Qi , Yang Lili , Zhao Erlong , Liang Lianyou , Tong Yan’ an 
Published: April 2018

AbstractMulching is critical for increasing water availability and hence winter wheat production in dryland farming systems. A two-year study was conducted to assess the effects of mulches on soil water storage (SWS), temperature, water use efficiency (WUE) and yields of winter wheat on the Loess Plateau. Four treatments were examined: conventional flat planting (CK), straw mulch (FPS), transparent plastic film mulch (FPP) and ridge-furrow with plastic film-mulched ridge and straw-mulched furrow (RFPS). Compared with CK, RFPS greatly increased SWS from 0–60 cm, FPP increased SWS from 0–40 cm, and FPS slightly increased SWS from 0–60 cm; however, FPP significantly (P < 0.05) decreased SWS from 61–100 cm. RFPS and FPP increased soil temperatures in cold seasons relative to CK, especially in RFPS (2.0–2.3 °C). Meanwhile, the rate of soil temperature increase was greater in RFPS and FPP than in CK but was lower in FPS. Mean yields were significantly increased in RFPS (56.78%), FPP (44.72%) and FPS (9.57%), and WUE was significantly increased in RFPS (44.04%) and in FPP (37.50%) compared with CK (P < 0.05). We conclude that ridge-furrow planting with plastic film-mulched ridge and straw-mulched furrow has a good potential for raising winter wheat production on the Loess Plateau.
Identification of QTN and candidate genes for Salinity Tolerance at the Germination and Seedling Stages in Rice by Genome-Wide Association Analyses
Authors: Naveed Shahzad Amir , Zhang Fan , Zhang Jian , Zheng Tian-Qing , Meng Li-Jun , Pang Yun-Long , Xu Jian-Long , Li Zhi-Kang 
Published: April 2018

AbstractTo facilitate developing rice varieties tolerant to salt stress, a panel of 208 rice mini-core accessions collected from 25 countries were evaluated for 13 traits associated with salt tolerance (ST) at the germination and seedling stages. The rice panel showed tremendous variation for all measured ST traits and eight accessions showing high levels of ST at either and/or both the germination and seedling stages. Using 395,553 SNP markers covering ~372 Mb of the rice genome and multi-locus mixed linear models, 20 QTN associated with 11 ST traits were identified by GWAS, including 6 QTN affecting ST at the germination stage and 14 QTN for ST at the seedling stage. The integration of bioinformatic with haplotype analyses for the ST QTN lets us identify 22 candidate genes for nine important ST QTN (qGR3, qSNK1, qSNK12, qSNC1, qSNC6, qRNK2, qSDW9a, qSST5 and qSST9). These candidate genes included three known ST genes (SKC1, OsTZF1 and OsEATB) for QTN qSNK1 qSST5 and qSST9. Candidate genes showed significant phenotypic differences in ST traits were detected between or among 2–4 major haplotypes. Thus, our results provided useful materials and genetic information for improving rice ST in future breeding and for molecular dissection of ST in rice.
Highly efficient base editing in bacteria using a Cas9-cytidine deaminase fusion
Authors: Zheng Ke , Wang Yang , Li Na , Jiang Fang-Fang , Wu Chang-Xian , Liu Fang , Chen Huan-Chun , Liu Zheng-Fei 
Published: April 2018

AbstractThe ability to precisely edit individual bases of bacterial genomes would accelerate the investigation of the function of genes. Here we utilized a nickase Cas9-cytidine deaminase fusion protein to direct the conversion of cytosine to thymine within prokaryotic cells, resulting in high mutagenesis frequencies in Escherichia coli and Brucella melitensis. Our study suggests that CRISPR/Cas9-guided base-editing is a viable alternative approach to generate mutant bacterial strains.
Direct observation of tin sites and their reversible interconversion in zeolites by solid-state NMR spectroscopy
Authors: Qi Guodong , Wang Qiang , Xu Jun , Wu Qinming , Wang Chao , Zhao Xingling , Meng Xiangju , Xiao Fengshou , Deng Feng 
Published: April 2018

AbstractMetal-substituted zeolites are an important type of solid Lewis acid with a wide range of applications. Despite the importance of this type of catalyst, identifying active sites can be challenging because different types of metal sites experience similar environments in zeolites. Here we show direct observation of different tin sites in Sn-β zeolite. Two types of open tin sites are unambiguously identified via correlating the hydroxyl groups to Sn atoms with one- and two-dimensional proton-detected 1H/119Sn correlation solid-state NMR spectroscopy, which only amounts to ca. 17% of the total tin content. A reversible transformation between the open and closed tin site is observed. The results provide valuable insights into the nature of tin sites in Sn-β zeolite and open an avenue for the use of proton-detected solid-state NMR methods for characterization of metal sites in zeolite catalysts.
Multi‐contact radiofrequency microelectromechanical systems switch with power divider/combiner structure for high power applications
Authors: Gong Zhuhao , Zhang Yulong , Guo Xin , Liu Zewen 
Published: April 2018

Design, fabrication, and measurement of a metal‐contact radiofrequency (RF) microelectromechanical systems switch with a power divider/combiner structure for high power applications are presented in this work. The multi‐contact switch with parallel cantilever beams is implemented in a Y‐junction power divider/combiner, which suppresses the uneven current distribution through each contact and results in higher power handling capability at high frequency. The measurement results indicate the excellent RF performance of the switch fabricated on the Borofloat glass substrate with insertion loss and isolation of 0.22 dB and 29 dB@10 GHz, respectively. A lumped‐element model is developed and it fits well with the measured S‐parameters with the contact resistance of 0.6 Ω and up‐state capacitance of 1 fF for each contact. The switch can handle power up to 2 W@10 GHz under prolonged hold‐down conditions for 2 h. The reliability measurement shows that the packaged switch can operate for over 1 million cycles at 200 mA under cold‐switching conditions.