ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    facet.materialart.
    Unknown
    Evidence from cyclostomes for complex regionalization of the ancestral vertebrate brain (2016)
    Nature Publishing Group (NPG)
    Details
    Publication Date: 2016-02-16
    Description: The vertebrate brain is highly complex, but its evolutionary origin remains elusive. Because of the absence of certain developmental domains generally marked by the expression of regulatory genes, the embryonic brain of the lamprey, a jawless vertebrate, had been regarded as representing a less complex, ancestral state of the vertebrate brain. Specifically, the absence of a Hedgehog- and Nkx2.1-positive domain in the lamprey subpallium was thought to be similar to mouse mutants in which the suppression of Nkx2-1 leads to a loss of the medial ganglionic eminence. Here we show that the brain of the inshore hagfish (Eptatretus burgeri), another cyclostome group, develops domains equivalent to the medial ganglionic eminence and rhombic lip, resembling the gnathostome brain. Moreover, further investigation of lamprey larvae revealed that these domains are also present, ruling out the possibility of convergent evolution between hagfish and gnathostomes. Thus, brain regionalization as seen in crown gnathostomes is not an evolutionary innovation of this group, but dates back to the latest vertebrate ancestor before the divergence of cyclostomes and gnathostomes more than 500 million years ago.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Sugahara, Fumiaki -- Pascual-Anaya, Juan -- Oisi, Yasuhiro -- Kuraku, Shigehiro -- Aota, Shin-ichi -- Adachi, Noritaka -- Takagi, Wataru -- Hirai, Tamami -- Sato, Noboru -- Murakami, Yasunori -- Kuratani, Shigeru -- England -- Nature. 2016 Mar 3;531(7592):97-100. doi: 10.1038/nature16518. Epub 2016 Feb 15.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Evolutionary Morphology Laboratory, RIKEN, Kobe 650-0047, Japan. ; Division of Biology, Hyogo College of Medicine, Nishinomiya 663-8501, Japan. ; Development and Function of Inhibitory Neural Circuits, Max Planck Florida Institute for Neuroscience, Jupiter, Florida 33458, USA. ; Phyloinformatics Unit, RIKEN Center for Life Science Technologies, Kobe 650-0047, Japan. ; Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois 60637, USA. ; Division of Gross Anatomy and Morphogenesis, Niigata University Graduate School of Medical and Dental Sciences, Niigata 950-8510, Japan. ; Graduate School of Science and Engineering, Ehime University, Matsuyama 790-8577, Japan.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26878236" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Brain/*anatomy & histology/*embryology ; Female ; Hagfishes/*anatomy & histology/*embryology/genetics ; Humans ; Lampreys/*anatomy & histology/*embryology/genetics/growth & development ; Larva/anatomy & histology ; Male ; Mice ; Molecular Sequence Data ; *Phylogeny ; Synteny/genetics
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Published by Nature Publishing Group (NPG)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 2
    facet.materialart.
    Unknown
    Lightning Attachment Processes of Three Natural Lightning Discharges (2015)
    Wiley
    Details
    Publication Date: 2015-09-26
    Description: Using a high-speed optical imaging system specifically designed for observing the lightning attachment process, we have documented the attachment process for six strokes in three natural lightning flashes. All strokes initiate at a height above ground, and propagate bi-directionally from that height, similar to the return strokes of artificially initiated (triggered) lightning previously reported by Wang at al. [2013, 2014]. Though the data are quite limited, these natural return strokes suggest a correlation between larger peak current and greater initiation height. Initiation heights determined here span 12–60 m with a typical uncertainty of less than 10 m. The initial upward return stroke luminosity speeds range from (0.8±0.2) to (2.0±0.4)×10 8 m/s. Two first return strokes downward luminosity speeds are assessed as (1.6±0.3) ×10 7 m/s and (1.4±0.3)×10 8 m/s. One of the first return strokes appeared to be initiated with a stepping pulse discharge of its leader as an inseparable part of the return stroke.
    Print ISSN: 0148-0227
    Topics: Geosciences , Physics
    Published by Wiley on behalf of American Geophysical Union (AGU).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 3
    facet.materialart.
    Unknown
    Transcriptional activation of elephant shark mineralocorticoid receptor by corticosteroids, progesterone, and spironolactone (2019)
    The American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2019
    Description: 〈p〉The mineralocorticoid receptor (MR) is a nuclear receptor and part of a large and diverse family of transcription factors that also includes receptors for glucocorticoids, progesterone, androgens, and estrogens. The corticosteroid aldosterone is the physiological activator of the MR in humans and other terrestrial vertebrates; however, its activator is not known in cartilaginous fish, the oldest group of extant jawed vertebrates. Here, we analyzed the ability of corticosteroids and progesterone to activate the full-length MR from the elephant shark (〈i〉Callorhinchus milii〈/i〉). On the basis of their measured activities, aldosterone, cortisol, 11-deoxycorticosterone, corticosterone, 11-deoxcortisol, progesterone, and 19-norprogesterone are potential physiological mineralocorticoids. However, aldosterone, the physiological mineralocorticoid in humans and other terrestrial vertebrates, is not found in cartilaginous or ray-finned fish. Although progesterone activates MRs in ray-finned fish, progesterone does not activate MRs in humans, amphibians, or alligator, suggesting that during the transition to terrestrial vertebrates, progesterone lost the ability to activate the MR. Both elephant shark MR and human MR are expressed in the brain, heart, ovary, testis, and other nonepithelial tissues, suggesting that MR expression in diverse tissues evolved in the common ancestor of jawed vertebrates. Our data suggest that 19-norprogesterone– and progesterone-activated MR may have unappreciated functions in reproductive physiology.〈/p〉
    Print ISSN: 1945-0877
    Electronic ISSN: 1937-9145
    Topics: Biology , Medicine
    Published by The American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 4
    facet.materialart.
    Unknown
    Direct observation of spin-polarized bulk bands in an inversion-symmetric semiconductor (2014)
    Springer Nature
    Details
    Publication Date: 2014-11-01
    Description: Nature Physics 10, 835 (2014). doi:10.1038/nphys3105 Authors: J. M. Riley, F. Mazzola, M. Dendzik, M. Michiardi, T. Takayama, L. Bawden, C. Granerød, M. Leandersson, T. Balasubramanian, M. Hoesch, T. K. Kim, H. Takagi, W. Meevasana, Ph. Hofmann, M. S. Bahramy, J. W. Wells & P. D. C. King Methods to generate spin-polarized electronic states in non-magnetic solids are strongly desired to enable all-electrical manipulation of electron spins for new quantum devices. This is generally accepted to require breaking global structural inversion symmetry. In contrast, here we report the observation from spin- and angle-resolved photoemission spectroscopy of spin-polarized bulk states in the centrosymmetric transition-metal dichalcogenide WSe2. Mediated by a lack of inversion symmetry in constituent structural units of the bulk crystal where the electronic states are localized, we show how spin splittings up to 0.5 eV result, with a spin texture that is strongly modulated in both real and momentum space. Through this, our study provides direct experimental evidence for a putative locking of the spin with the layer and valley pseudospins in transition-metal dichalcogenides, of key importance for using these compounds in proposed valleytronic devices.
    Print ISSN: 1745-2473
    Electronic ISSN: 1745-2481
    Topics: Physics
    Published by Springer Nature
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 5
    facet.materialart.
    Unknown
    Correlation between the channel-bottom light intensity and channel-base current of a rocket triggered lightning flash (2014)
    Wiley
    Details
    Publication Date: 2014-11-15
    Description: The correlations between channel-bottom light intensity and channel-base current of all discharge processes of a rocket-and-wire triggered lightning flash, including ICC pulses, ICC pulse background continuing current (IBCC), return strokes, M-components and M-component background continuing currents (MBCC), have been investigated. A rough linear correlation has been found between the current squared and the light intensity for ICC pulses (including peaks of different ICC pulses), IBCC, the initial rising stage (IRS) of return strokes (including current peaks of different strokes), and MBCC. The slopes of the correlation regression lines for the current squared versus light intensity of ICC pulses and IBCC are similar, but they are about 2 ~ 3 times smaller than the slopes of MBCC and 5 ~ 7 times smaller than the slopes of the IRS of return strokes. In contrast, a rough linear correlation has been found between the current and the light intensity for the later slow decay stage (LSDS) of return strokes and for the M-components. The slopes of the correlation regression lines of the current versus the light intensity for these latter two processes are found to be similar. No simple correlation has been found between the current and the light intensity for the initial fast decay stage (IFDS) of return strokes. The duration of the IFDS of return strokes generally lasts from several microseconds to several tens of microseconds and is more or less directly proportional to the corresponding peak return-stroke current squared. A time delay ranging from 12 µs to 300 µs has been found between the current and the light intensity of all ICC pulses and M-components. The time delay decreases as the corresponding peak current increases.
    Print ISSN: 0148-0227
    Topics: Geosciences , Physics
    Published by Wiley on behalf of American Geophysical Union (AGU).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 6
    facet.materialart.
    Unknown
    Initiation processes of return strokes in rocket-triggered lightning (2013)
    Wiley
    Details
    Publication Date: 2013-08-21
    Description: [1]  Using a high speed optical imaging system operated at a time resolution of either 10 ns or 100 ns, we have documented the initiation process of 14 return strokes in 4 rocket-triggered lightning flashes. Of the 14 strokes, 9 occurred following dart leaders and 5 following dart-stepped leaders. The return strokes are found to initiate at heights ranging from 7.2 ± 1.4 m to 21.0 ± 4.6 m above the lightning termination point. Return strokes with larger peak current tend to initiate higher. All the return strokes show initial bidirectional (upward and downward from their initiation height) propagation. We have been able to estimate the initial upward propagation speeds below 60 m for all of the return strokes. The resultant speeds range from 0.4 × 10 8  m/s to 2.5 × 10 8  m/s. For the downward propagation speeds, only six strokes among the 14 strokes allow us to perform a reasonable estimation. Those downward speeds range from 0.6 × 10 8  m/s to 1.9 × 10 8  m/s.
    Print ISSN: 0148-0227
    Topics: Geosciences , Physics
    Published by Wiley on behalf of American Geophysical Union (AGU).
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...