Electron-scale measurements of magnetic reconnection in space

Magnetic reconnection is a fundamental physical process in plasmas whereby stored magnetic energy is converted into heat and kinetic energy of charged particles. Reconnection occurs in many astrophysical plasma environments and in laboratory plasmas. Using very high time resolution measurements, NASA’s Magnetospheric Multiscale Mission (MMS) has found direct evidence for electron demagnetization and acceleration at sites along the sunward boundary of Earth’s magnetosphere where the interplanetary magnetic field reconnects with the terrestrial magnetic field. We have (i) observed the conversion of magnetic energy to particle energy, (ii) measured the electric field and current, which together cause the dissipation of magnetic energy, and (iii) identified the electron population that carries the current as a result of demagnetization and acceleration within the reconnection diffusion/dissipation region

Two-Photon Imaging of Calcium in Virally Transfected Striate Cortical Neurons of Behaving Monkey

Two-photon scanning microscopy has advanced our understanding of neural signaling in non-mammalian species and mammals. Various developments are needed to perform two-photon scanning microscopy over prolonged periods in non-human primates performing a behavioral task. In striate cortex in two macaque monkeys, cortical neurons were transfected with a genetically encoded fluorescent calcium sensor, memTNXL, using AAV1 as a viral vector. By constructing an extremely rigid and stable apparatus holding both the two-photon scanning microscope and the monkey's head, single neurons were imaged at high magnification for prolonged periods with minimal motion artifacts for up to ten months. Structural images of single neurons were obtained at high magnification. Changes in calcium during visual stimulation were measured as the monkeys performed a fixation task. Overall, functional responses and orientation tuning curves were obtained in 18.8% of the 234 labeled and imaged neurons. This demonstrated that the two-photon scanning microscopy can be successfully obtained in behaving primates

Structural Characteristics and Stellar Composition of Low Surface Brightness Disk Galaxies

We present UBVI surface photometry of a sample of low surface brightness (LSB) disk galaxies. LSB disk galaxies are fairly well described as exponential disks with no preferred value for either scale length, central surface brightness, or rotational velocity. Indeed, the distribution of scale lengths is indistinguishable from that of high surface brightness spirals, indicating that dynamically similar galaxies (e.g., those with comparable Rv^2) exist over a large range in surface density. These LSB galaxies are strikingly blue. The complete lack of correlation between central surface brightness and color rules out any fading scenario. Similarly, the oxygen abundances inferred from HII region spectra are uncorrelated with color so the low metallicities are not the primary cause of the blue colors. While these are difficult to interpret in the absence of significant star formation, the most plausible scenario is a stellar population with a young mean age stemming from late formation and subsequent slow evolution. These properties suggest that LSB disks formed from low initial overdensities with correspondingly late collapse times.Comment: Astronomical Journal, in press 45 pages uuencoded postscript (368K) including 9 multipart figures also available by anonymous ftp @ ftp.ast.cam.ac.uk /pub/ssm/phot.uu CAP-30-210442962983742937

New parallel dictionaries of the Russian, French, German and English languages : in four parts : fourth part, English dictionary /

Half-title: Parallel dictionaries of the Russian, French, German and English languages.The other parts have titles in Russian, French, and German, respectively.Mode of access: Internet

Parallelʹnye slovari i͡azykov russkago, frant͡suzskago, ni͡emet͡skago i anglīĭskago, dli͡a upotreblenīi͡a Russkago i͡unoshestva po slovari͡am Akademīi rossīĭskoĭ, Akademīi frant͡suzskoĭ, Adelunga, Geĭnzīusa, Dzhonsona, Vebstera, i po drugim leksikonam,

Later editions published under title: Novye parallelʹnye slovari ...The other parts have titles in French, German and English, respectively.Mode of access: Internet

New parallel dictionaries of the Russian, French, German and English languages.

Mode of access: Internet

Novye parallelʹnye slovari i͡azykov russkago, frant͡suzskago, ni͡emet͡skago i anglīĭskago v chetyrekh chasti͡akh, po slovari͡am Rossīĭskoĭ akademīi, Frant͡suzskoĭ akademīi, Adelunga, Geĭzīusa, Dzhonsona, Spirsa, i po drugim leksikonam chastʹ pervai͡a--russkīĭ slovarʹ /

Ch. 1. Russko-frant͡suzsko-ni͡emet͡sko-anglīĭskīĭ slovarʹ.Mode of access: Internet

Novye parallelʹnye slovari i͡azykov russkago, frant͡suzkago, ni͡emet͡skago i anglīi͡skago v chetyrekh chasti͡akh

First and second editions published under title: Parallelnye slovari ...The other parts have titles in French, German, and English respectively.Binder's title: Parallel-Wörterbuch.Mode of access: Internet

Nouveaux dictionnaires parallèles des langues russe, française, allemande et anglaise en quatre parties, rédigés d'après les dictionnaires de l'Académie russe, l'Académie française, Adelung, Heinsius, Johnson, Spiers et autres lexicographes : deuxième partie--dictionnaire français /

The other volumes have titles in English, German and Russian respectively.On leaf preceding t.p.: Dictionnaires parallèles des langues russe, française, allemande et anglaise.Mode of access: Internet