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31.
Zusammenfassung Calcitonin als neues kalzium- und phosphor-senkendes Hormon wurde auf seine Wirkung auf die inorganische Pyrophosphataseaktivität von Knochen untersucht. Eine Steigerung der alkalinen Pyrophosphataseaktivität wurde vor der starken Senkung des Serum-Kalziums beobachtet. 相似文献
32.
33.
Toyohisa Fujita Hao Chen Kai-tuo Wang Chun-lin He You-bin Wang Gjergj Dodbiba Yue-zhou Wei 《矿物冶金与材料学报》2021,28(2):179-192
The demand for Li-ion batteries (LIBs) for vehicles is increasing. However, LIBs use valuable rare metals, such as Co and Li, as well as environmentally toxic reagents. LIBs are also necessary to utilize for a long period and to recycle useful materials. The reduction, reuse, and recycle (3R) of spent LIBs is an important consideration in constructing a circular economy. In this paper, a flowsheet of the 3R of LIBs is proposed and methods to reduce the utilization of valuable rare metals and the amount of spent LIBs by remanufacturing used parts and designing new batteries considering the concept of 3R are described. Next, several technological processes for the reuse and recycling of LIBs are introduced. These technologies include discharge, sorting, crushing, binder removal, physical separation, and pyrometallurgical and hydrometallurgical processing. Each process, as well as the related physical, chemical, and biological treatments, are discussed. Finally, the problem of developed technologies and future subjects for 3R of LIBs are described. 相似文献
34.
1 Results We have already established a methodology of supramolecular organization of porphyrin and phthalocyanine by complementary coordination of the imidazolyl substituent to their metal centers.Since the stability constants reached a range of 1011 to 1012 M-1 in nonpolar solvents,it allowed construction of stable structures such as special pair of photosynthetic reaction center and light-harvesting antenna complex of photosynthetic bacteria.Here,we report one-dimensional array of porphyrin for the d... 相似文献
35.
Jin D Liu HX Hirai H Torashima T Nagai T Lopatina O Shnayder NA Yamada K Noda M Seike T Fujita K Takasawa S Yokoyama S Koizumi K Shiraishi Y Tanaka S Hashii M Yoshihara T Higashida K Islam MS Yamada N Hayashi K Noguchi N Kato I Okamoto H Matsushima A Salmina A Munesue T Shimizu N Mochida S Asano M Higashida H 《Nature》2007,446(7131):41-45
CD38, a transmembrane glycoprotein with ADP-ribosyl cyclase activity, catalyses the formation of Ca2+ signalling molecules, but its role in the neuroendocrine system is unknown. Here we show that adult CD38 knockout (CD38-/-) female and male mice show marked defects in maternal nurturing and social behaviour, respectively, with higher locomotor activity. Consistently, the plasma level of oxytocin (OT), but not vasopressin, was strongly decreased in CD38-/- mice. Replacement of OT by subcutaneous injection or lentiviral-vector-mediated delivery of human CD38 in the hypothalamus rescued social memory and maternal care in CD38-/- mice. Depolarization-induced OT secretion and Ca2+ elevation in oxytocinergic neurohypophysial axon terminals were disrupted in CD38-/- mice; this was mimicked by CD38 metabolite antagonists in CD38+/+ mice. These results reveal that CD38 has a key role in neuropeptide release, thereby critically regulating maternal and social behaviours, and may be an element in neurodevelopmental disorders. 相似文献
36.
Kodama R Norreys PA Mima K Dangor AE Evans RG Fujita H Kitagawa Y Krushelnick K Miyakoshi T Miyanaga N Norimatsu T Rose SJ Shozaki T Shigemori K Sunahara A Tampo M Tanaka KA Toyama Y Yamanaka T Zepf M 《Nature》2001,412(6849):798-802
Modern high-power lasers can generate extreme states of matter that are relevant to astrophysics, equation-of-state studies and fusion energy research. Laser-driven implosions of spherical polymer shells have, for example, achieved an increase in density of 1,000 times relative to the solid state. These densities are large enough to enable controlled fusion, but to achieve energy gain a small volume of compressed fuel (known as the 'spark') must be heated to temperatures of about 108 K (corresponding to thermal energies in excess of 10 keV). In the conventional approach to controlled fusion, the spark is both produced and heated by accurately timed shock waves, but this process requires both precise implosion symmetry and a very large drive energy. In principle, these requirements can be significantly relaxed by performing the compression and fast heating separately; however, this 'fast ignitor' approach also suffers drawbacks, such as propagation losses and deflection of the ultra-intense laser pulse by the plasma surrounding the compressed fuel. Here we employ a new compression geometry that eliminates these problems; we combine production of compressed matter in a laser-driven implosion with picosecond-fast heating by a laser pulse timed to coincide with the peak compression. Our approach therefore permits efficient compression and heating to be carried out simultaneously, providing a route to efficient fusion energy production. 相似文献
37.
Recent advances in the fabrication of quasicrystals in soft matter systems have increased the length scales for quasicrystals into the mesoscale range (20 to 500 ?ngstr?ms). Thus far, dendritic liquid crystals, ABC-star polymers, colloids and inorganic nanoparticles have been reported to yield quasicrystals. These quasicrystals offer larger length scales than intermetallic quasicrystals (a few ?ngstr?ms), thus potentially leading to optical applications through the realization of a complete photonic bandgap induced via multiple scattering of light waves in virtually all directions. However, the materials remain far from structurally ideal, in contrast to their intermetallic counterparts, and fine control over the structure through a self-organization process has yet to be attained. Here we use the well-established self-assembly of surfactant micelles to produce a new class of mesoporous silicas, which exhibit 12-fold (dodecagonal) symmetry in both electron diffraction and morphology. Each particle reveals, in the 12-fold cross-section, an analogue of dodecagonal quasicrystals in the centre surrounded by 12 fans of crystalline domains in the peripheral part. The quasicrystallinity has been verified by selected-area electron diffraction and quantitative phason strain analyses on transmission electron microscope images obtained from the central region. We argue that the structure forms through a non-equilibrium growth process, wherein the competition between different micellar configurations has a central role in tuning the structure. A simple theoretical model successfully reproduces the observed features and thus establishes a link between the formation process and the resulting structure. 相似文献
38.
Columns for visual features of objects in monkey inferotemporal cortex. 总被引:21,自引:0,他引:21
At early stages of the mammalian visual cortex, neurons with similar stimulus selectivities are vertically arrayed through the thickness of the cortical sheet and clustered in patches or bands across the surface. This organization, referred to as a 'column', has been found with respect to one-dimensional stimulus parameters such as orientation of stimulus contours, eye dominance of visual inputs, and direction of stimulus motion. It is unclear, however, whether information with extremely high dimensions, such as visual shape, is organized in a similar columnar fashion or in a different manner in the brain. Here we report that the anterior inferotemporal area of the monkey cortex, the final station of the visual cortical stream crucial for object recognition, consists of columns, each containing cells responsive to similar visual features of objects. 相似文献
39.
Parihar MS Parihar A Fujita M Hashimoto M Ghafourifar P 《Cellular and molecular life sciences : CMLS》2008,65(7-8):1272-1284
α-Synuclein is a neuron-specific protein that contributes to the pathology of Parkinson’s disease via mitochondria-related mechanisms. The present study investigated possible interaction of α-synuclein with mitochondria and
consequences of such interaction. Using SHSY cells overexpressing α-synuclein A53T mutant or wild-type, as well as isolated
rat brain mitochondria, the present study shows that α-synuclein localizes at the mitochondrial membrane. In both SHSY cells
and isolated mitochondria, interaction of α-synuclein with mitochondria causes release of cytochrome c, increase of mitochondrial calcium and nitric oxide, and oxidative modification of mitochondrial components. These findings
suggest a pivotal role for mitochondria in oxidative stress and apoptosis induced by α-synuclein.
Received 27 December 2007; received after revision 7 February 2008; accepted 8 February 2008 相似文献
40.
K. Fujita Y. Shimomura J. Fujita K. J. Mori 《Cellular and molecular life sciences : CMLS》1985,41(4):504-505
Summary Nude mice were inoculated with BMA1 cells. These are cells which produce granulocyte-macrophage colony stimulating factor (GM-CSF); They are derived from mouse bone marrow stromal cells transfected with adenovirus 5 DNA. Progressive neutrophilia developed as the tumor grew, but disappeared quickly after local tumor excision. Media conditioned with tumor cells had GM-CSF but neither erythropoietin, nor burst-promoting activity. In all the tumors which developed, focal areas of bone formation were found among fibrosarcomatous tissues. 相似文献