225 research outputs found

    The concurrent variability of East Asian subtropical and polarā€front jets and its implication for the winter climate anomaly in China

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    The variability of East Asian upper level westerly jets in winter is studied with regard to the concurrent existence of subtropical jet (East Asian subtropical jet (EASJ)) and polarā€front jet (East Asian polarā€front jet (EAPJ)) using the National Centers for Environmental Prediction/National Center for Atmospheric Research reanalysis. In the distribution of jet occurrence revealed in 6ā€hourly data, two jet branches along 30Ā°N and 55Ā°N, corresponding to locations of EASJ and EAPJ, respectively, are separated over the Tibetan Plateau. The leading two modes of zonalā€mean zonal wind in East Asia extracted from a massā€weighted empirical orthogonal function analysis are characterized by the intensity changes and location displacements of two jets. The key regions for EASJ and EAPJ are then defined to represent variabilities of these two jets. Correlation analysis indicates that the subseasonal variation of EAPJ precedes EASJ by around 5ā€‰days, which can be interpreted as waveā€mean flow interactions via synopticā€scale transient eddy activities. Based on the pentad intensity indices of two jets, the concurrent variabilities of EASJ and EAPJ are investigated with typical temperature and precipitation anomalies in China. The results suggest that by taking account of the two jets, we are able to get a more comprehensive understanding of the winter climate.Key PointsThe leading modes of zonalā€mean zonal wind in East Asia and the concurrent existence of East Asian subtropical jet and polarā€front jetTheir concurrent variability can be interpreted as waveā€mean flow interactions via synopticā€scale transient eddy activitiesA comprehensive understanding of the winter climate in China from the perspective of double jetsPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/133534/1/jgrd53070_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/133534/2/jgrd53070.pd

    Modulating signaling networks by CRISPR/Cas9-mediated transposable element insertion

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    In a recent past, transposable elements (TEs) were referred to as selfish genetic components only capable of copying themselves with the aim of increasing the odds of being inherited. Nonetheless, TEs have been initially proposed as positive control elements acting in synergy with the host. Nowadays, it is well known that TE movement into host genome comprises an important evolutionary mechanism capable of increasing the adaptive fitness. As insights into TE functioning are increasing day to day, the manipulation of transposition has raised an interesting possibility of setting the host functions, although the lack of appropriate genome engineering tools has unpaved it. Fortunately, the emergence of genome editing technologies based on programmable nucleases, and especially the arrival of a multipurpose RNA-guided Cas9 endonuclease system, has made it possible to reconsider this challenge. For such purpose, a particular type of transposons referred to as miniature inverted-repeat transposable elements (MITEs) has shown a series of interesting characteristics for designing functional drivers. Here, recent insights into MITE elements and versatile RNA-guided CRISPR/Cas9 genome engineering system are given to understand how to deploy the potential of TEs for control of the host transcriptional activity.Fil: Vaschetto, Luis Maria Benjamin. Consejo Nacional de Investigaciones CientĆ­ficas y TĆ©cnicas. Centro CientĆ­fico TecnolĆ³gico Conicet - CĆ³rdoba. Instituto de Diversidad y EcologĆ­a Animal. Universidad Nacional de CĆ³rdoba. Facultad de Ciencias Exactas FĆ­sicas y Naturales. Instituto de Diversidad y EcologĆ­a Animal; Argentina. Universidad Nacional de CĆ³rdoba. Facultad de Ciencias Exactas, FĆ­sicas y Naturales. CĆ”tedra de Diversidad Animal I; Argentin

    Miniature Invertedā€“Repeat Transposable Elements (MITEs) Have Been Accumulated through Amplification Bursts and Play Important Roles in Gene Expression and Species Diversity in Oryza sativa

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    Miniature invertedā€“repeat transposable elements (MITEs) are predicted to play important roles on genome evolution. We developed a BLASTN-based approach for de novo identification of MITEs and systematically analyzed MITEs in rice genome. The genome of rice cultivar Nipponbare (Oryza sativa ssp. japonica) harbors 178,533 MITE-related sequences classified into 338 families. Pairwise nucleotide diversity and phylogenetic tree analysis indicated that individual MITE families were resulted from one or multiple rounds of amplification bursts. The timing of amplification burst varied considerably between different MITE families or subfamilies. MITEs are associated with 23,623 (58.2%) genes in rice genome. At least 7,887 MITEs are transcribed and more than 3,463 were transcribed with rice genes. The MITE sequences transcribed with rice coding genes form 1,130 pairs of potential natural sense/antisense transcripts. MITEs generate 23.5% (183,837 of 781,885) of all small RNAs identified from rice. Some MITE families generated small RNAs mainly from the terminals, while other families generated small RNAs predominantly from the central region. More than half (51.8%) of the MITE-derived small RNAs were generated exclusively by MITEs located away from genes. Genome-wide analysis showed that genes associated with MITEs have significantly lower expression than genes away from MITEs. Approximately 14.8% of loci with full-length MITEs have presence/absence polymorphism between rice cultivars 93-11 (O. sativa ssp. indica) and Nipponbare. Considering that different sets of genes may be regulated by MITE-derived small RNAs in different genotypes, MITEs provide considerable diversity for O. sativa

    Measurements of the Mass and Full-Width of the Ī·c\eta_c Meson

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    In a sample of 58 million J/ĻˆJ/\psi events collected with the BES II detector, the process J/Ļˆā†’Ī³Ī·c\psi\to\gamma\eta_c is observed in five different decay channels: Ī³K+Kāˆ’Ļ€+Ļ€āˆ’\gamma K^+K^-\pi^+\pi^-, Ī³Ļ€+Ļ€āˆ’Ļ€+Ļ€āˆ’\gamma\pi^+\pi^-\pi^+\pi^-, Ī³KĀ±KS0Ļ€āˆ“\gamma K^\pm K^0_S \pi^\mp (with KS0ā†’Ļ€+Ļ€āˆ’K^0_S\to\pi^+\pi^-), Ī³Ļ•Ļ•\gamma \phi\phi (with Ļ•ā†’K+Kāˆ’\phi\to K^+K^-) and Ī³ppĖ‰\gamma p\bar{p}. From a combined fit of all five channels, we determine the mass and full-width of Ī·c\eta_c to be mĪ·c=2977.5Ā±1.0(stat.)Ā±1.2(syst.)m_{\eta_c}=2977.5\pm1.0 ({stat.})\pm1.2 ({syst.}) MeV/c2c^2 and Ī“Ī·c=17.0Ā±3.7(stat.)Ā±7.4(syst.)\Gamma_{\eta_c} = 17.0\pm3.7 ({stat.})\pm7.4 ({syst.}) MeV/c2c^2.Comment: 9 pages, 2 figures and 4 table. Submitted to Phys. Lett.

    \psi(2S) Decays into \J plus Two Photons

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    Using \gamma \gamma J/\psi, J/\psi \ra e^+ e^- and Ī¼+Ī¼āˆ’\mu^+ \mu^- events from a sample of 14.0Ɨ10614.0\times 10^6 \psip decays collected with the BESII detector, the branching fractions for \psip\ra \pi^0\J, \eta\J, and \psi(2S)\ar\gamma\chi_{c1},\gamma\chi_{c2}\ar\gamma\gamma\jpsi are measured to be B(\psip\ra \pi^0\J) = (1.43\pm0.14\pm0.13)\times 10^{-3}, B(\psip\ra \eta\J) = (2.98\pm0.09\pm0.23)%, B(\psi(2S)\ar\gamma\chi_{c1}\ar\gamma\gamma\jpsi) = (2.81\pm0.05\pm 0.23)%, and B(\psi(2S)\ar\gamma\chi_{c2}\ar\gamma\gamma\jpsi) = (1.62\pm0.04\pm 0.12)%.Comment: 7 pages, 6 figures. submitted to Phys. Rev.

    Evidence of psi(3770) non-DD-bar Decay to J/psi pi+pi-

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    Evidence of Ļˆ(3770)\psi(3770) decays to a non-DDĖ‰{D \bar D} final state is observed. A total of 11.8Ā±4.8Ā±1.311.8 \pm 4.8 \pm 1.3 \psi(3770) \to \PPJP events are obtained from a data sample of 27.7 pbāˆ’1\rm {pb^{-1}} taken at center-of-mass energies around 3.773 GeV using the BES-II detector at the BEPC. The branching fraction is determined to be BF(\psi(3770) \to \PPJP)=(0.34\pm 0.14 \pm 0.09)%, corresponding to the partial width of \Gamma(\psi(3770) \to \PPJP) = (80 \pm 33 \pm 23) keV.Comment: 8 pages, 7 figures, Submitted to Physics Letters

    Future of additive manufacturing: Overview of 4D and 3D printed smart and advanced materials and their applications

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    Ā© 2020 Elsevier B.V. 4D printing is an emerging field in additive manufacturing of time responsive programmable materials. The combination of 3D printing technologies with materials that can transform and possess shape memory and self-healing capabilities means the potential to manufacture dynamic structures readily for a myriad of applications. The benefits of using multifunctional materials in 4D printing create opportunities for solutions in demanding environments including outer space, and extreme weather conditions where human intervention is not possible. The current progress of 4D printable smart materials and their stimuli-responsive capabilities are overviewed in this paper, including the discussion of shape-memory materials, metamaterials, and self-healing materials and their responses to thermal, pH, moisture, light, magnetic and electrical exposures. Potential applications of such systems have been explored to include advancements in health monitoring, electrical devices, deployable structures, soft robotics and tuneable metamaterials

    Psi(2S) -> pi^+ pi^- J/psi Decay Distributions

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    Using a sample of 3.8 M psi(2S) events accumulated with the BES detector, the process psi(2S) -> pi^+ pi^- J/psi is studied. The angular distributions are compared with the general decay amplitude analysis of Cahn. We find that the dipion system requires some D-wave, as well as S-wave. On the other hand, the J/psi-(pi pi) relative angular momentum is consistent with being pure S-wave. The decay distributions have been fit to heavy quarkonium models, including the Novikov-Shifman model. This model, which is written in terms of the parameter kappa, predicts that D-wave should be present. We determine kappa = 0.183 +/- 0.002 +/- 0.003 based on the joint dipion mass - cos theta distribution. The fraction of D-wave as a function of the dipion mass is found to decrease with increasing dipion mass, in agreement with the model. We have also fit the Mannel-Yan model, another model that allows D-wave.Comment: 21 pages, 10 figure
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