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experimental platform for the investigation of magnetized-reverse-shock dynamics in the context of POLAR

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High Power Laser Science and engineering 2018年第3期6卷 36-49页

作者： B. Albertazzi e. Falize A. Pelka e Brack e Kroll R. Yurchak e. Brambrink e Mabey N. Ozaki S. Pikuz L. Van Box Som J. M. Bonnet-Bidaud J. e. Cross e. Filippov G. Gregori R. Kodama M. Mouchet T. Morita Y. Sakawa R. e Drake C. C. Kuranz M. J.-e. Manuel C. Li e Tzeferacos D. Lamb U. Schramm M. Koenig LULI- CNRS Ecole Polytechnique CEA: Universite Paris-Saclay UPMC Univ Paris 06: Sorbonne Universites- F-91128 Palaiseau cedex France CeA-DAM-DIF F-91297 Arpajon France CeA Saclay DSM/Irfu/Service d'Astrophysique F-91191 Gif-sur- Yvette France Helmholtz-Zentrum Dresden - Rossendorf HZDR Bautzner Landstrαβe 400 01328 Dresden Germany Department of Atmospheric Oceanic and Space Sciences University of Michigan Ann Arbor M148109 USA Graduate School of engineering Osaka University Suita Osaka 565-0871 Japan JIHT-RAS 13-2 lzhorskaya st. Moscow 125412 Russia National Research Nuclear University MePhl Moscow 115409 Russia Department of Physics University of Oxford Parks Road Oxford OX1 3PU UK Institute of Laser engineering Osaka University Suita Osaka 565-0871 Japan LUTH Observatoire de Paris UMR CNRS 8102 Universite Paris Diderot 92190 Meudon France Department of energy engineering Science Faculty of Engineering Sciences Kyushu University Japan General Atomics San Diego CA 92121 USA Plasma Science and Fusion Center Massachusetts Institute of Technology 77 Massachusetts Avenue Cambridge MA 02139 USA Flash Center for Computational Science University of Chicago IL 60637 USA

The influence of a strong external magnetic field on the collimation of a high Mach number plasma flow and its collision with a solid obstacle is investigated experimentally and numerically. The laser irradiation （I - 2 × 10^14 W. cm-2） of a multilayer target generates a shock wave that produces a rear side plasma expanding flow. Immersed in a homogeneous 10 T external magnetic field, this plasma flow propagates in vacuum and impacts an obstacle located a few mm from the main target. A reverse shock is then formed with typical velocities of the order of 15-20 4- 5 km/s. The experimental results are compared with 2D radiative magnetohydrodynamic simulations using the FLASH code. This platform allows investigating the dynamics of reverse shock, mimicking the processes occurring in a cataclysmic variable of polar type.

关键词： accretion processes high-power laser hydrodynamics laboratory astrophysics polar radiative shocks

Transcriptional Control of SeT DOMAIN GROUP 8 and CAROTeNOID ISOMeRASe during Arabidopsis Development

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Molecular Plant 2010年第1期3卷 174-191页

作者： Christopher I. Cazzonelli Andrea C. Roberts Melanie e. Carmody Barry J. Pogson Australian Research Council Centre of excellence in Plant energy Biology Research School of Biology The Australian National University Canberra ACT0200 Australia

Carotenoids are pigments required for photosynthesis, photoprotection and the production of carotenoid- derived hormones such as ABA and strigolactones. The carotenoid biosynthetic pathway bifurcates after lycopene to produce epsilon- and beta-carotenoids and this branch is critical for determining carotenoid composition. Here, we show how the branch point can be regulated by the chromatin-modifying histone methyltransferase, Set Domain Group 8 （SDG8） targeting the carotenoid isomerase （CRTISO）. SDG8 is required to maintain permissive expression of CRTISO during seedling development, in leaves, shoot apex, and some floral organs. The CRTISO and SDG8 promoters show overlapping tissue-specific patterns of reporter gene activity. Interestingly, CRTISO showed atypical reporter gene expression in terms of greater variability between different lines compared to the Cauliflower Mosaic Virus 35S promoter （CaMV35s） and ~LCY promoters, potentially due to chromosomal position effects. Regulation of the CRTISO promoter was dependent in part upon the presence or absence of SDG8. Knockouts of SDG8 （carotenoid and chloroplast regulation （ccrl）） and CRTISO （ccr2） result in altered carotenoid composition and this could be restored in ccr2 using the CaMV35s or CRTISO promoters. In contrast, varying degrees of GUS expression and carotenoid complementation by CRTISO overexpression using CaMV35S or CRTISO promoters in the ccrl background demonstrated that both the CRTISO promoter and open reading frame are necessary for SDG8-mediated expression of CRTISO.

关键词： Photosynthesis secondary metabolism--terpenoids, isoprenoids, and carotenoids chloroplast biology epigenetics gene expression gene regulation.

Simultaneous effects of external electric Field and Conduction Band Nonparabolicity on Optical Properties of a GaAs Quantum Dot embedded at the Center of a GaAlAs Nano-Wire

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Communications in Theoretical Physics 2014年第6期61卷 765-772页

作者： Gh.Safarpour M.A.Izadi M.Novzari e.Niknam M.M.Golshan Zarghan Branch Islamic Azad University Young Researchers and elite Club Zarghan Branch Islamic Azad University Department of Physics College of Sciences Shiraz University

An investigation of the optical properties of a GaAs spherical quantum dot which is located at the center of a Ga1-xAlx As cylindrical nano-wire has been performed in the presence of an external electric field. The band nonparabolieity effect is also considered using the energy dependent effective mass approximation. The energy eigenvalues and corresponding wave functions are calculated by finite difference approximation and the reliability of calculated wave functions is checked by computing orthogonality. Using computed energy eigenvalues and wave functions, the linear, third-order nonlinear and total optical absorption coefficients and refractive index changes are examined in detail. It is found that （i） Presence of electric field causes both blue and red shifts in absorption spectrum; （ii） The absorption coefficients shift toward lower energies by taking into account the conduction band nonparabolicity; （iii） For large values of electric field the effect of conduction band nonparabolieity is less dominant and parabolic band is estimated correctly; （iv） In the presence of electric field and conduction band nonparabolicity the nonlinear term of absorption coefficient rapidly increases by increasing incident optical intensity. In other words, the saturation in optical spectrum occurs at lower incident optical intensities.

关键词： nonlinear optics conduction band nonparabolicity electric field spherical quantum dot

p53 promotes AKT and SP1-dependent metabolism through the pentose phosphate pathway that inhibits apoptosis in response to Nutlin-3a

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Journal of Molecular Cell Biology 2018年第4期10卷 331-340页

作者： Text Lei Duan Ricardo e. Perez Ling Chen Lothar A. Blatter Carl G. Maki Department of Cell & Molecular Medicine Rush University Medical Center Chicago IL 60612 USA Department of Laboratory Medicine Shiyan Taihe Hospital College of Biomedical Engineering Hubei University of Medicine Shiyan 442000 China Department of Physiology & Biophysics Rush University Medical Center Chicago IL 60612 USA

Nutlin-3a is a MDM2 antagonist and preclinical drug that activates p53. Cells with MDM2 gene amplification are especially prone to Nutlin-3a-induced apoptosis, though the basis for this is unclear. Glucose metabolism can inhibit apoptosis in response to Nutlin-3a through mechanisms that are incompletely understood. Glucose metabolism through the pentose phosphate pathway （PPP） produces NADPH that can protect cells from potentially lethal reactive oxygen species （ROS）. We compared apoptosis and glucose metabolism in cancer cells with and without MDM2 gene amplification treated with Nutlin-3a. Apoptosis in MDM2-amplified cells was associated with a reduction in glycolysis and the PPP, reduced NADPH, increased ROS, and depletion of the transcription factor SP1, which normally promotes PPP gene expression. In contrast, glycolysis and the PPP were maintained or increased in MDM2 non-amplified cells treated with Nutlin-3a. This was dependent on p53-mediated AKT activation and was associated with maintenance of SP1 and continued expression of PPP genes. Knockdown or inhibition of AKT, SP1, or the PPP sensitized MDM2-non-amplified cells to apoptosis. The data indicate that p53 promotes AKT and SP1-dependent activation of the PPP that protects cells from Nutlin-3a-induced apoptosis. These findings provide insight into how glucose metabolism reduces Nutlin-3a-induced apoptosis, and also provide a mechanism for the heightened sensitivity of MDM2-amplified cells to apoptosis in response to Nutlin-3a.

关键词： Nutlin p53 MDM2 SP1 glycolysis pentose phosphate pathway

TRANSMISSION eLeCTRON MICROSCOPY INVeSTIGATIONS OF LOW-PReSSURe CVD GROWTH AND STRAIN ReLAXATION OF Ge ISLANDS ON Si(110)

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Acta Metallurgica Sinica(english Letters) 2005年第3期18卷 427-432页

作者： e.Spiecker L.Zhang H.M.Lu W.Jaeger L.Vescan MicroanalysisofMaterials FacultyofEngineeringChrisfian-Albrechts-UniversityKielKaiserstraβe224143KielGermany InstituteofThinFilmsandInterfaces ResearchCenterJiilichGmbH52425JiilichGermany

Shapes, dimensions, arrangements and the microstructure of self-assembled island s fabricated by low-pressure chemical vapour deposition (LPCVD) of Ge at 700℃ o nto Si(110) substrates have been investigated for different nominal Ge coverage by transmission electron microscopy (TeM) of plan-view and cross-section specime ns and have been compared with photoluminescence (PL) measurements of Si-capped layer samples. The transition from the 2-dimensional layer to the 3-dimensional island growth mode takes place for a Ge deposition of nominally less than 2 mono layers. Upon this transition, many coherent islands and few larger islands with extended defects are observed. The coherent islands possess a dome-like shape an d lateral sizes up to 130nm. Photoluminescence spectra show island-related peaks whose energy positions are shifted towards lower energy with higher Ge coverage .

关键词： Si-Ge heteroepitaxy surface transmission electron microscopy Nanostructure

Growth and Cd Accumulation of Orychophragmus violaceus as Affected by Inoculation of Cd-Tolerant Bacterial Strains

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Pedosphere 2014年第3期24卷 322-329页

作者： LIANG Xia He Chi-Quan NI Gang TANG Gui-e CHeN Xue-Ping LeI Yan-Ru School of environmental and Chemical engineering Shanghai University

Beneficial interactions between microorganisms and plants, particularly in the rhizosphere, are a research area of global interest. Four cadmium(Cd)-tolerant bacterial strains were isolated from heavy metal-contaminated sludge and their effects on Cd mobility in soil and the root elongation and Cd accumulation of Orychophragmus violaceus were explored to identify the capability of metalresistant rhizobacteria for promoting the growth of O. violaceus roots on Cd-contaminated soils. The isolated strains, namely, Bacillus subtilis, B. cereus, B. megaterium, and Pseudomonas aeruginosa, significantly enhanced the plant Cd accumulation. The Cd concentrations in the roots and shoots were increased by up to 2.29- and 2.86-fold, respectively, by inoculation of B. megaterium, as compared with the uninoculated control. The bacterial strains displayed different effects on the shoot biomass. Compared with the uninoculated plants, the shoot biomass of the inoculated plants was slightly increased by B. megaterium and significantly decreased by the other strains. B. megaterium was identified as the best candidate for enhancing Cd accumulation in O. violaceus. Thus, this study provides novel insight into the development of plant-microbe systems for phytoremediation.

关键词： heavy metals phytoremediation plant-microbe systems rhizobacteria soil contamination

Cell Death Mechanisms Induced by Cytotoxic Lymphocytes

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Cellular & Molecular Immunology 2009年第1期6卷 15-25页

作者： Chávez-Galán L Arenas-Del Angel MC Zenteno e Chávez R Lascurain R Departamento de Bioquímica Instituto Nacional de Enfermedades Respiratorias "Ismael Cosío Villegas" Departamento de Bioquímica Facultad de MedicinaUniversidad Nacional Autónoma de México

One of the functions of the immune system is to recognize and destroy abnormal or infected cells to maintain homeostasis. This is accomplished by cytotoxic lymphocytes. Cytotoxicity is a highly organized multifactor process. Here, we reviewed the apoptosis pathways induced by the two main cytotoxic lymphocyte subsets, natural killer （NK） cells and CD8^＋T cells. In base to recent experimental evidence, we reviewed NK receptors involved in recognition of target-cell, as well as lytic molecules such as perforin, granzymes-A and -B, and granulysin. In addition, we reviewed the Fas-FasL intercellular linkage mediated pathway, and briefly the cross-linking of tumor necrosis factor （TNF） and TNF receptor pathway. We discussed three models of possible molecular interaction between lytic molecules from effector cytotoxic cells and target-cell membrane to induction of apoptosis. Cellular ＆ Molecular Immunology.

关键词： apoptosis cytotoxic cell granule-dependent exocytosis FasL TNF

Optimizing methyl-eugenol aromatherapy to maximize posttreatment effects to enhance mating competitiveness of male Bactrocera carambolae （Diptera： Tephritidae）

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Insect Science 2015年第5期22卷 661-669页

作者： Ihsan ul Haq Marc J.B. Vreysen Carlos Caceres Todd e. Shelly Jorge Hendrichs Insect Pest Control Laboratory Joint FAOIIAEA Division of Nuclear Techniques in Food and Agriculture Seibersdorf Austria National Agricultural Research Centre Park Road Islamabad Pakistan USDAIAPHIS 41-650 Ahiki Street Waimanalo HI 96795 USA and Insect Pest Control Section Joint FAOIIAEA Division of Nuclear Techniques in Food and Agriculture Vienna Austria

Methyl-eugenol （Me）（1,2-dimethoxy-4-（2-propenyl）benzene）, a natural phy- tochemical, did enhance male Bactrocera carambolae Drew ＆ Hancock （Diptera： Tephri- tidae） mating competitiveness 3 d after ingestion. enhanced male mating competitiveness can significantly increase the effectiveness of the sterile insect technique （SIT）. Me appli- cation to mass reared sterile flies by feeding is infeasible. Me application by aromatherapy however, would be a very practical way of Me application in fly emergence and release facilities. This approach was shown to enhance mating competitiveness ofB. carambolae 3 d posttreatment （DPT）. Despite this added benefit, every additional day of delaying re- lease will reduce sterile fly quality and will add cost to SIT application. The present study was planned to assess the effects of Me-aromatherapy on male B. carambolae mating competitiveness 1DPT and 2DPT. Me aromatherapy 1DPT or 2DPT did enhance mating competitiveness of B. carambolae males whereas Me feeding 1DPT and 2DPT did not. Male mating competitiveness was enhanced by the Me aromatherapy irrespective if they received 1DPT, 2DPT or 3DPT. Me aromatherapy, being a viable approach for its applica- tion, did enhance mating competitiveness of male B. carambolae 1 d posttreatrnent as Me feeding did 3 d after ingestion.

关键词： Bactrocera carambolae mating competitiveness Me aromatherapy methyl-eugenol Me feeding posttreatment effect SIT

Time dependent integration of matrix metalloproteinases and their targeted substrates directs axonal sprouting and synaptogenesis following central nervous system injury

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Neural Regeneration Research 2014年第4期9卷 362-376页

作者： Linda L.Phillips Julie L.Chan Adele e.Doperalski Thomas M.Reeves Department of Anatomy and Neurobiology Virginia Commonwealth UniversityRichmondVAUSA

Over the past two decades, many investigators have reported how extracellular matrix molecules act to regulate neuroplasticity. The majority of these studies involve proteins which are targets of matrix metalloproteinases. Importantly, these enzyme/substrate interactions can regulate degenerative and regenerative phases of synaptic plasticity, directing axonal and dendritic reorganization after brain insult. The present review first summarizes literature support for the prominent role of matrix metalloproteinases during neuroregeneration, followed by a discussion of data contrasting adaptive and maladaptive neuroplasticity that reveals time-dependent metalloproteinase/substrate regulation of postinjury synaptic recovery. The potential for these enzymes to serve as therapeutic targets for enhanced neuroplasticity after brain injury is illustrated with experiments demonstrating that metalloproteinase inhibitors can alter adaptive and maladaptive outcome. Finally, the complexity of metalloproteinase role in reactive synaptogenesis is revealed in new studies showing how these enzymes interact with immune molecules to mediate cellular response in the local regenerative environment, and are regulated by novel binding partners in the brain extracellular matrix. Together, these different examples show the complexity with which metalloproteinases are integrated into the process of neuroregeneration, and point to a promising new angle for future studies exploring how to facilitate brain plasticity.

关键词： neuroregeneration reactive synaptogenesis matrix metalloproteinases brain injury adaptive and maladaptive neuroplasticity metalloproteinase inhibition osteopontin lipocalin 2