Statistical Properties of Molecular Ions in the Ring Current Observed by the Arase (ERG) Satellite

Molecular ions in the magnetosphere can be a tracer of fast ion outflows from the deep ionosphere. Statistical properties of molecular ions (O2+/NO+/N2+) in the ring current are investigated based on ion composition measurements (<180 keV/q) by medium‐energy particle experiments‐electron analyzer and low‐energy particle experiments‐ion mass analyzer instruments on board the Arase (Exploration of energization and Radiation in Geospace, ERG) satellite. The investigated period from late March to December 2017 includes 11 geomagnetic storms with the minimum Dst index less than −40 nT. The molecular ions are observed in the region of L = 2.5–6.6 and clearly identified at energies above ~12 keV during most magnetic storms. During quiet times, molecular ions are not observed. The average energy density ratio of the molecular ions to O+ is ~3%. The ratio tends to increase with the size of magnetic storms. Existence of molecular ions even during small magnetic storms suggests that the fast ion outflow from the deep ionosphere occurs frequently during geomagnetically active periods

Vaspin Is an Adipokine Ameliorating ER Stress in Obesity as a Ligand for Cell-Surface GRP78/MTJ-1 Complex

It is unknown whether adipokines derived from adipose tissues modulate endoplasmic reticulum (ER) stress induced in obesity. Here, we show that visceral adipose tissue-derived serine protease inhibitor (vaspin) binds to cell-surface 78-kDa glucose-regulated protein (GRP78), which is recruited from ER to plasma membrane under ER stress. Vaspin transgenic mice were protected from diet-induced obesity, glucose intolerance, and hepatic steatosis, while vaspin-deficient mice developed glucose intolerance associated with upregulation of ER stress markers. With tandem affinity tag purification using HepG2 cells, we identified GRP78 as an interacting molecule. The complex formation of vaspin, GRP78, and murine tumor cell DnaJ-like protein 1 (MTJ-1) (DnaJ homolog, subfamily C, member 1) on plasma membrane was confirmed by cell-surface labeling with biotin and immunoprecipitation in liver tissues and H-4-II-E-C3 cells. The addition of recombinant human vaspin in the cultured H-4-II-E-C3 cells also increased the phosphorylation of Akt and AMP-activated protein kinase (AMPK) in a dose-dependent manner, and anti-GRP78 antibodies completely abrogated the vaspin-induced upregulation of pAkt and pAMPK Vaspin is a novel ligand for cell-surface GRP78/MTJ-1 complex, and its subsequent signals exert beneficial effects on ER stress-induced metabolic dysfunctions. Diabetes 61:2823-2832, 201

Remote Detection of Drift Resonance Between Energetic Electrons and Ultralow Frequency Waves: Multisatellite Coordinated Observation by Arase and Van Allen Probes

We report the electron flux modulations without corresponding magnetic fluctuations from unique multipoint satellite observations of the Arase (Exploration of Energization and Radiation in Geospace) and the Van Allen Probe (Radiation Belt Storm Probe [RBSP])‐B satellites. On 30 March 2017, both Arase and RBSP‐B observed periodic fluctuations in the relativistic electron flux with energies ranging from 500 keV to 2 MeV when they were located near the magnetic equator in the morning and dusk local time sectors, respectively. Arase did not observe Pc5 pulsations, while they were observed by RBSP‐B. The clear dispersion signature of the relativistic electron fluctuations observed by Arase indicates that the source region is limited to the postnoon to the dusk sector. This is confirmed by RBSP‐B and ground‐magnetometer observations, where Pc5 pulsations are observed to drift‐resonate with relativistic electrons on the duskside. Thus, Arase observed the drift‐resonance signatures “remotely,” whereas RBSP‐B observed them “locally.

GAIA: a gram-based interaction analysis tool – an approach for identifying interacting domains in yeast

<p>Abstract</p> <p>Background</p> <p>Protein-Protein Interactions (PPIs) play important roles in many biological functions. Protein domains, which are defined as independently folding structural blocks of proteins, physically interact with each other to perform these biological functions. Therefore, the identification of Domain-Domain Interactions (DDIs) is of great biological interests because it is generally accepted that PPIs are mediated by DDIs. As a result, much effort has been put on the prediction of domain pair interactions based on computational methods. Many DDI prediction tools using PPIs network and domain evolution information have been reported. However, tools that combine the primary sequences, domain annotations, and structural annotations of proteins have not been evaluated before.</p> <p>Results</p> <p>In this study, we report a novel approach called Gram-bAsed Interaction Analysis (GAIA). GAIA extracts peptide segments that are composed of fixed length of continuous amino acids, called n-grams (where n is the number of amino acids), from the annotated domain and DDI data set in <it>Saccharomyces cerevisiae </it>(budding yeast) and identifies a list of n-grams that may contribute to DDIs and PPIs based on the frequencies of their appearance. GAIA also reports the coordinate position of gram pairs on each interacting domain pair. We demonstrate that our approach improves on other DDI prediction approaches when tested against a gold-standard data set and achieves a true positive rate of 82% and a false positive rate of 21%. We also identify a list of 4-gram pairs that are significantly over-represented in the DDI data set and may mediate PPIs.</p> <p>Conclusion</p> <p>GAIA represents a novel and reliable way to predict DDIs that mediate PPIs. Our results, which show the localizations of interacting grams/hotspots, provide testable hypotheses for experimental validation. Complemented with other prediction methods, this study will allow us to elucidate the interactome of cells.</p

Penetration of MeV electrons into the mesosphere accompanying pulsating aurorae

Pulsating aurorae (PsA) are caused by the intermittent precipitations of magnetospheric electrons (energies of a few keV to a few tens of keV) through wave-particle interactions, thereby depositing most of their energy at altitudes ~ 100 km. However, the maximum energy of precipitated electrons and its impacts on the atmosphere are unknown. Herein, we report unique observations by the European Incoherent Scatter (EISCAT) radar showing electron precipitations ranging from a few hundred keV to a few MeV during a PsA associated with a weak geomagnetic storm. Simultaneously, the Arase spacecraft has observed intense whistler-mode chorus waves at the conjugate location along magnetic field lines. A computer simulation based on the EISCAT observations shows immediate catalytic ozone depletion at the mesospheric altitudes. Since PsA occurs frequently, often in daily basis, and extends its impact over large MLT areas, we anticipate that the PsA possesses a significant forcing to the mesospheric ozone chemistry in high latitudes through high energy electron precipitations. Therefore, the generation of PsA results in the depletion of mesospheric ozone through high-energy electron precipitations caused by whistler-mode chorus waves, which are similar to the well-known effect due to solar energetic protons triggered by solar flares

New genetic loci link adipose and insulin biology to body fat distribution.

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms

C–H···p and C=O···p Intermolecular Interactions in Dibenzyl-3,6-dimethylpyrazine-2,5-dicarboxylate

Abstract A new pyrazine compound, has been synthesised and characterised by single-crystal X-ray diffraction: monoclinic, P21/c with a = 11.0707(3) Å, b = 5.23700(10) Å, c = 16.6997(5) Å, ß = 103.5385(16)°, Mr = 376.40, V = 941.30(4) Å3, Z = 2. Each molecule possesses C i symmetry with the two halves of the molecule related by an inversion centre. C–H···p and C=O···p interactions held the molecules together. Index Abstract C–H···p and C=O···p intermolecular interactions in dibenzyl-3,6-dimethylpyrazine-2,5-dicarboxylate Joana A. Silva, Ana C. Santos, Ana T. Marques, Manuela Ramos Silva, Ana Matos Beja, Abílio J. F. N. Sobrala In dibenzyl-3,6-dimethylpyrazine-2,5-dicarboxylate, each molecule possesses C i symmetry. The molecules are assembled in chains via carbonyl···p interactions

Statistical Properties of Molecular Ions in the Ring Current Observed by the Arase (ERG) Satellite

Molecular ions in the magnetosphere can be a tracer of fast ion outflows from the deep ionosphere. Statistical properties of molecular ions (O2+/NO+/N2+) in the ring current are investigated based on ion composition measurements (<180 keV/q) by medium‐energy particle experiments‐electron analyzer and low‐energy particle experiments‐ion mass analyzer instruments on board the Arase (Exploration of energization and Radiation in Geospace, ERG) satellite. The investigated period from late March to December 2017 includes 11 geomagnetic storms with the minimum Dst index less than −40 nT. The molecular ions are observed in the region of L = 2.5–6.6 and clearly identified at energies above ~12 keV during most magnetic storms. During quiet times, molecular ions are not observed. The average energy density ratio of the molecular ions to O+ is ~3%. The ratio tends to increase with the size of magnetic storms. Existence of molecular ions even during small magnetic storms suggests that the fast ion outflow from the deep ionosphere occurs frequently during geomagnetically active periods