450 research outputs found
Physical Relation of Source I to IRc2 in the Orion KL Region
We present mid-infrared narrow-band images of the Orion BN/KL region, and
N-band low-resolution spectra of IRc2 and the nearby radio source "I." The
distributions of the silicate absorption strength and the color temperature
have been revealed with a sub-arcsecond resolution. The detailed structure of
the 7.8 micron/12.4 micron color temperature distribution was resolved in the
vicinity of IRc2. A mid-infrared counterpart to source I has been detected as a
large color temperature peak. The color temperature distribution shows an
increasing gradient from IRc2 toward source I, and no dominant temperature peak
is seen at IRc2. The spectral energy distribution of IRc2 could be fitted by a
two-temperature component model, and the "warmer component" of the infrared
emission from IRc2 could be reproduced by scattering of radiation from source
I. IRc2 itself is not self-luminous, but is illuminated and heated by an
embedded luminous young stellar object located at source I.Comment: 20 pages, 11 figures. Minor corrections had been done in the ver.2.
Accepted for publication in PAS
Measurements of Vegetation Distribution Using Various Local Remote Sensing Techniques
Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv
Spinogenesis and Pruning in the Anterior Ventral Inferotemporal Cortex of the Macaque Monkey: An Intracellular Injection Study of Layer III Pyramidal Cells
Pyramidal cells grow and mature at different rates among different cortical areas in the macaque monkey. In particular, differences across the areas have been reported in both the timing and magnitude of growth, branching, spinogenesis, and pruning in the basal dendritic trees of cells in layer III. Presently available data suggest that these different growth profiles reflect the type of functions performed by these cells in the adult brain. However, to date, studies have focused on only a relatively few cortical areas. In the present investigation we quantified the growth of the dendritic trees of layer III pyramidal cells in the anterior ventral portion of cytoarchitectonic area TE (TEav) to better comprehend developmental trends in the cerebral cortex. We quantified the growth and branching of the dendrities, and spinogenesis and pruning of spines, from post-natal day 2 (PND2) to four and a half years of age. We found that the dendritic trees increase in size from PND2 to 7 months of age and thereafter became smaller. The dendritic trees became increasingly more branched from PND2 into adulthood. There was a two-fold increase in the number of spines in the basal dendritic trees of pyramidal cells from PND2 to 3.5 months of age and then a 10% net decrease in spine number into adulthood. Thus, the growth profile of layer III pyramidal cells in the anterior ventral portion of the inferotemporal cortex differs to that in other cortical areas associated with visual processing
Successive phase transitions to antiferromagnetic and weak-ferromagnetic long-range orders in quasi-one-dimensional antiferromagnet CuMoO
Investigation of the magnetism of CuMoO single crystal, which has
antiferromagnetic (AF) linear chains interacting with AF dimers, reveals an AF
second-order phase transition at K. Although weak
ferromagnetic-like behavior appears at lower temperatures in low magnetic
fields, complete remanent magnetization cannot be detected down to 0.5 K.
However, a jump is observed in the magnetization below weak ferromagnetic (WF)
phase transition at K when a tiny magnetic field along
the a axis is reversed, suggesting that the coercive force is very weak. A
component of magnetic moment parallel to the chain forms AF long-range order
(LRO) below , while a perpendicular component is disordered above
at zero magnetic field and forms WF-LRO below .
Moreover, the WF-LRO is also realized with applying magnetic fields even
between and . These results are explainable by both
magnetic frustration among symmetric exchange interactions and competition
between symmetric and asymmetric Dzyaloshinskii-Moriya exchange interactions.Comment: 7 pages, 7 figure
High-temperature thermoelectric properties of the double-perovskite ruthenium oxide (SrLa)ErRuO
We have prepared polycrystalline samples of (SrLa)ErRuO
and (SrLa)YRuO, and have measured the resistivity, Seebeck
coefficient, thermal conductivity, susceptibility and x-ray absorption in order
to evaluate the electronic states and thermoelectric properties of the doped
double-perovskite ruthenates. We have observed a large Seebeck coefficient of
-160 V/K and a low thermal conductivity of 7 mW/cmK for =0.1 at 800 K
in air. These two values are suitable for efficient oxide thermoelectrics,
although the resistivity is still as high as 1 cm. From the
susceptibility and x-ray absorption measurements, we find that the doped
electrons exist as Ru in the low spin state. On the basis of the
measured results, the electronic states and the conduction mechanism are
discussed.Comment: 6 pages, 4 figures, J. Appl. Phys. (accepted
Finite-size energy gap in weak and strong topological insulators
The non-trivialness of a topological insulator (TI) is characterized either
by a bulk topological invariant or by the existence of a protected metallic
surface state. Yet, in realistic samples of finite size this non-trivialness
does not necessarily guarantee the gaplessness of the surface state. Depending
on the geometry and on the topological indices, a finite-size energy gap of
different nature can appear, and correspondingly, exhibits various scaling
behaviors of the gap. The spin-to-surface locking provides one of such
gap-opening mechanisms, resulting in a power-law scaling of the energy gap.
Weak and strong TI's show different degrees of sensitivity to the geometry of
the sample. As a noteworthy example, a strong TI nanowire of a rectangular
prism shape is shown to be more gapped than that of a weak TI of precisely the
same geometry.Comment: 16 pages, 18 figure
Control technique for planetary rover
Beginning next century, several schemes for sending a planetary rover to the moon or Mars are being planned. As part of the development program, autonomous navigation technology is being studied to allow the rover the ability to move autonomously over a long range of unknown planetary surface. In the previous study, we ran the autonomous navigation experiment on an outdoor test terrain by using a rover test-bed that was controlled by a conventional sense-plan-act method. In some cases during the experiment, a problem occurred with the rover moving into untraversable areas. To improve this situation, a new control technique has been developed that gives the rover the ability of reacting to the outputs of the proximity sensors, a reaction behavior if you will. We have developed a new rover test-bed system on which an autonomous navigation experiment was performed using the newly developed control technique. In this outdoor experiment, the new control technique effectively produced the control command for the rover to avoid obstacles and be guided to the goal point safely
Two-staged treatment strategy in patients with severe carotid or cerebrovascular diseases undergoing coronary artery bypass grafting.
Purpose : There is no clear consensus on how to treat patients undergoing coronary artery bypass grafting (CABG) who have severe concomitant carotidcerebral artery stenosis. The aim of this study was to evaluate our surgical results in patients with severe carotid and/or cerebrovascular disease undergoing CABG. Methods :Between October 2003 and April 2009, a total of 47 such patients were treated at our institution with the following strategies: (1) protective carotid artery stenting for severe carotid stenosis performed either before (n = 20) or after (n = 5) CABG or (2) a superficial temporal artery-middle cerebral artery anastomosis procedure followed by CABG if indicated (n = 4). Off-pump CABG was performed in 75% of the patients. Results. There were no major perioperative strokes or in-hospital deaths; however, three patients had transient ischemic attacks and two had minor strokes during the early post-CABG period. All of the patients with postoperative cerebrovascular events had had unilateral carotid artery occlusion. There were no late deaths during the follow-up period (up to 6 years, with a mean of 27 months). However, major adverse cardiocerebrovascular events (MACCE) occurred in seven patients (14.9%). The rates of freedom from MACCE at 1 and 3 years were 92% and 74%, respectively. Conclusion :It appears that our two-staged approach is safe and may reduce the risk of postoperative cerebrovascular events
Human group II phospholipase A2 in normal and diseased intervertebral discs
AbstractWe measured calcium-dependent phospholipase A2 (PLA2) activity and immunoreactive group II PLA2 levels of 54 normal discs obtained from cadavers and 73 disc samples surgically obtained from patients with spinal disorders, including intervertebral disc herniations, spondylosis, and spondylolisthesis. Both cadaveric and surgical disc specimens contained about two-fold greater PLA2 activity than the ileal mucosa, one of the richest sources of group II PLA2. Discs of middle-aged cases had significantly higher activity than those of younger and elder cases. In cadaveric normal discs, calcium-dependent PLA2 activity was significantly higher in females than in males. Annulus fibrosus and nucleus pulposus contained the same PLA2 levels. In diseases discs, herniated fragments that had extruded or protruded out of the discs possessed lower activity than other parts of discs in the intervertebral space. Immunoreactive group II PLA2 levels of intervertebral discs closely correlated with PLA2 enzymatic activity. We purified a PLA2 from human intervertebral disc to homogeneity to further identify the isozymic nature of discal PLA2. Its NH2-terminal amino acid sequence and molecular weight were identical to those of human group II PLA2. Immunohistochemical analysis using a monoclonal anti-group II PLA2 antibody showed that in both annulus fibrosus and nucleus pulposus chondrocyte contained intense grou II PLA2 immunoreactivity in their cytoplasm, and that the matrix contained no substantial immunoreactivity. These results suggest that group II PLA2 in chondrocytes has important physiological roles in discal ordinary metabolism, maintaining discal homeostasis
Multimodal treatment for resectable epithelial type malignant pleural mesothelioma
BACKGROUND: Malignant pleural mesothelioma is a rare malignancy. The outcome remains poor despite complete surgical resection. PATIENTS AND METHODS: Eleven patients with histologicaly proven epithelial type malignant pleural mesothelioma undergoing extrapleural pneumonectomy with systemic chemotherapy and/or radiotherapy before and after surgical resection were retrospectively reviewed. RESULTS: Ten out of 11 patients underwent complete surgical resection, of these 7 patients had stage I disease. Of these 7 patients, 5 are alive without any recurrence, a 2-year survival rate of 80% was observed in this group. There was no operative mortality or morbidity. CONCLUSION: Extrapleural pneumonectomy with perioperative adjuvant treatment is safe and effective procedure for epithelial type malignant pleural mesothelioma
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