X-ray imaging of Kelvin-Helmholtz waves at the magnetopause

This paper simulates the Kelvin-Helmholtz wave (KHW)-induced X-ray emissions at the low-latitude magnetopause based on a global MHD code. A method is proposed to extract the KHW information from the X-ray intensity measured by a hypothetical X-ray telescope onboard a satellite assumed with a low Earth orbit. Specifically, the X-ray intensity at high latitude is subtracted from the intensity map as a background to highlight the role of KHW. Using this method, global features of KHW such as the vortex velocity, perturbation degree, spatial distribution, and temporal evolution could be evaluated from the X-ray intensity map. The validity of this method during intervals of solar wind disturbances is also verified. According to the simulation results, X-ray imaging of KHW is suggested as a promising observation technique to essentially “see” the large-scale configuration and evolution of KHW for the first time

TBP2 gene may not be associated with primary ovarian insufficiency

<p><b>Objective:</b> It has previously been reported that TATA-binding protein 2 (TBP2) knockout female mice are sterile. Our objective was to assess the association between the TBP2 gene and primary ovarian insufficiency (POI) in a Chinese population.</p> <p><b>Methods:</b> A cohort of 60 POI patients matched with 60 fertile controls was recruited by Nanjing Medical University. There were no interventions. The complete TBP2 exon regions were analyzed by direct sequencing in all POI patients and controls.</p> <p><b>Results:</b> A known single nucleotide polymorphism (rs8019270) was identified in both POI and control groups. There was no difference in the genotype distribution or allelic frequencies between the control group and the POI group. No plausible pathogenic mutations were identified.</p> <p><b>Conclusion:</b> Our study indicates that the TBP2 gene is not responsible for idiopathic POI in the Chinese Han population.</p

An Ideal Ultrafine-Grained Structure for High Strength and High Ductility

<div><p>An ideal ultrafine-grained (UFG) microstructure for high strength and high ductility should have short dislocation-slip path to impede dislocation slip and very low dislocation density to ensure more room for dislocation accumulation. Such a microstructure is hard to produce, especially for UFG metals produced by severe plastic deformation techniques. Here, we report an ideal UFG structure produced by reverse transformation of deformation-induced martensite in 304 L austenitic stainless steel. It produced small grains and a high density of nanotwins for both high strength and high ductility. This approach is applicable to face-centered cubic metals with low stacking fault energy.</p></div

Molecular cloning, expression and polymorphism of goose <i>LRP8</i> gene

<div><p></p><p>1. The low-density lipoprotein receptor-related protein 8 (LRP8), a member of the low-density lipoprotein receptor (LDLR) gene family, participates in the supplying of lipid during follicular development. The objective of the study was to identify and characterise the <i>LRP8</i> gene in goose.</p><p>2. A 2867 bp fragment that covered the complete coding region (CDS) of goose (<i>Anser cygnoides</i>) <i>LRP8</i> gene was cloned. It encoded a protein of 917 amino acid residues containing a 24-amino acid signal peptide and 5 functional domains. The goose LRP8 showed high nucleic acid and amino acid identities with those in other species.</p><p>3. Similarly to duck <i>LRP8</i> gene, two splice variants of LRP8, LRP8-1 (containing 8 ligand-binding repeats) and LRP8-2 (containing 7 ligand-binding repeats), were identified in goose.</p><p>4. Semi-quantitative RT-PCR analysis indicates that the <i>LRP8-1</i> transcript is expressed in heart, liver, spleen, lung, kidney, breast muscle, duodenum, hypothalamus, pituitary and ovary, negligible or absent in sebum and oviduct, and the <i>LRP8-2</i> transcript is widely expressed in all examined tissues.</p><p>5. A total of 7 SNPs were identified in the coding region of the goose <i>LRP8</i> gene.</p></div

The DNA topoisomerase VI–B Subunit OsMTOPVIB Is Essential for Meiotic Recombination Initiation in Rice

The DNA topoisomerase VI–B Subunit OsMTOPVIB Is Essential for Meiotic Recombination Initiation in Ric

Molecular cloning and tissue distribution of peroxisome proliferator-activated receptor-alpha (<i>PPARα</i>) and gamma (<i>PPARγ</i>) in the pigeon (<i>Columba livia domestica</i>)

<div><p></p><p>1. Peroxisome proliferator-activated receptors (PPAR) are involved in lipid metabolism through transcriptional regulation of target gene expression. The objective of the current study was to clone and characterise the <i>PPARα</i> and <i>PPARγ</i> genes in pigeon.</p><p>2. The full-length of 1941-bp <i>PPARα</i> and 1653-bp <i>PPARγ</i> were cloned from pigeons. The two genes were predicted to encode 468 and 475 amino acids, respectively. Both proteins contained two C4-type zinc fingers, a nuclear hormone receptor DNA-binding region signature and a HOLI domain (ligand binding domain of hormone receptors), and had high identities with other corresponding avian genes.</p><p>3. Using quantitative real-time PCR, pigeon <i>PPARα</i> gene expression was shown to be high in kidney, liver, gizzard and duodenum whereas <i>PPARγ</i> was predominantly expressed in adipose tissue.</p></div

Insights into the tectonic evolution of the North China Craton through comparative tectonic analysis: A record of outward growth of Precambrian continents

Archean cratons have map patterns and rock associations that are diagnostic of the Wilson Cycle. The North China Craton (NCC) consists of several distinctly different tectonic units, but the delineation and understanding of the significance of individual sutures and the rocks between them has been controversial. We present an actualistic tectonic division and evolution of the North China Craton based on Wilson Cycle and comparative tectonic analysis that uses a multi-disciplinary approach in order to define sutures, their ages, and the nature of the rocks between them, to determine their mode of formation and means of accretion or exhumation, and propose appropriate modern analogues. The eastern unit of the craton consists of several different small blocks assembled between 2.6 and 2.7 Ga ago, that resemble fragments of accreted arcs from an assembled archipelago similar to those in the extant SW Pacific. A thick Atlantic-type passive margin developed on the western side of the newly assembled Eastern Block by 2.6–2.5 Ga. A > 1300 km-long arc and accretionary prism collided with the margin of the Eastern Block at 2.5 Ga, obducting ophiolites and ophiolitic mélanges onto the block, and depositing a thick clastic wedge in a foreland basin farther into the Eastern Block. This was followed by an arc-polarity reversal, which led to a short-lived injection of mantle wedge-derived melts to the base of the crust that led to the intrusion of mafic dikes and arc-type granitoid (TTG) plutons with associated metamorphism. By 2.43 Ga, the remaining open ocean west of the accreted arc closed with the collision of an oceanic plateau now preserved as the Western Block with the collision-modified margin of the Eastern Block, causing further deformation in the Central Orogenic Belt. 2.4–2.35 Ga rifting of the newly amalgamated continental block formed a rift along its center, and new oceans within the other two rift arms, which removed a still-unknown continental fragment from its northern margin. By 2.3 Ga an arc collided with a new Atlantic-type margin developed over the rift sequence along the northern margin of the craton, and thus was converted to an Andean margin through arc-polarity reversal. Andean margin tectonics affected much of the continental block from 2.3 to 1.9 Ga, giving rise to a broad E-W swath of continental margin magmas, and retro-arc sedimentary basins including a foreland basin superimposed on the passive northern margin. The horizontal extent of these tectonic components is similar to that across the present-day Andes in South America. From 1.88 to 1.79 Ga a granulite facies metamorphic event was superimposed across the entire continental block with high-pressure granulites and eclogites in the north, and medium-pressure granulites across the whole craton to the south. The scale and duration of this post-collisional event is similar to that in Central Asia that resulted from the Cenozoic India-Asia collision. The deep crustal granulites and volcanic rocks on the surface today, interpreted to be anatectic melts from deep crustal granulites, are similar to high-grade metamorphic rocks and partial melts presently forming at mid-crustal levels beneath Tibet. Structural fabrics in lower-crustal migmatites related to this event reveal that they flowed laterally parallel to the collision boundary, in a way comparable to what is speculated to be happening in the deep crust of the Himalayan/Tibetan foreland. We relate this continent-continent collision to the collision of the North China Craton with the postulated Columbia (Nuna) Continent. The NCC broke out of the Columbia Continent between 1753–1673 Ma, as shown by the formation of a suite of anorthosite, mangerite, charnockite, and alkali-feldspar granites in an ENE-striking belt along the northern margin of the craton, whose intrusion was followed by the development of rifts and graben, mafic dike swarms, and eventually an Atlantic-type passive margin that signaled the beginning of a long period of tectonic quiescence and carbonate deposition for the NCC during Sinian times, which persisted into the Paleozoic. The style of tectonic accretion in the NCC changed at circa 2.5 Ga, from an earlier phase of accretion of arcs that are presently preserved in horizontal lengths of several hundred kilometers, to the accretion and preservation of linear arcs several thousand kilometers long with associated oceanic plateaus, microcontinents, and accretionary prisms. The style of progressively younger and westward outward accretion of different tectonic components is reminiscent of the style of accretion in the Superior Craton, and may signal the formation of progressively larger landmasses at the end of the Archean (perhaps like the Kenorland Continent), then into the Paleoproterozoic, culminating in the assembly of the Columbia (Nuna) Continent at 1.9–1.8 Ga

Kaposiform haemangioendothelioma- clinical features, complications and risk factors for Kasabach–Merritt phenomenon_bjd0457.pdf

Background Few studies have reported the clinical features, complications and predictors of Kasabach–Merritt phenomenon (KMP) associated with Kaposiform haemangioendothelioma (KHE). Objectives To determine the clinical characteristics present at diagnosis and to identify features that may aid clinicians in managing KHE. Methods We conducted a cohort study of 146 patients diagnosed with KHE. Results KHE precursors or lesions were present at birth in 521% of patients. In 918% of patients, lesions developed within the first year of life. The median age at diagnosis of KHE was 23 months (interquartile range 10–60). The extremities were the dominant location, representing 507% of all KHEs. Among KHEs in the cohort, 630% were mixed lesions (cutaneous lesions with deep infiltration). Approximately 70% of patients showed KMP. A KHE diagnosis was delayed by ≥ 1 month in 657% of patients with KMP. Patients with KMP were more likely to have major complications than patients without KMP ( P=0023). Young age ( 6 months), trunk location, large lesion size (> 50 cm) and mixed lesion type were associated with KMP in a univariate analysis. In the multivariate analysis, only age [odds ratio (OR) 119, 95% confidence interval (CI) 407–348; P large lesion size (OR 508, 95% CI 224–115; P (OR 296, 95% CI 123–713; P=0016) were associated with KMP. Conclusions Most KHEs appeared before 12 months of age. KHEs are associated with various major complications, which can occur in combination and develop early in the disease process. Young age, large lesion size and mixed lesion type are important predictors of KMP.</p

Chemical sensing with switchable transport channels in graphene grain boundaries

Grain boundaries can markedly affect the electronic, thermal, mechanical and optical properties of a polycrystalline graphene. While in many applications the presence of grain boundaries in graphene is undesired, here we show that they have an ideal structure for the detection of chemical analytes. We observe that an isolated graphene grain boundary has ~300 times higher sensitivity to the adsorbed gas molecules than a single-crystalline graphene grain. Our electronic structure and transport modelling reveal that the ultra-sensitivity in grain boundaries is caused by a synergetic combination of gas molecules accumulation at the grain boundary, together with the existence of a sharp onset energy in the transmission spectrum of its conduction channels. The discovered sensing platform opens up new pathways for the design of nanometre-scale highly sensitive chemical detectors