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1.
Space Sci Rev ; 201: 1-53, 2016 Jul.
Article in English | MEDLINE | ID: mdl-32908324

ABSTRACT

Chromospheric and coronal jets represent important manifestations of ubiquitous solar transients, which may be the source of significant mass and energy input to the upper solar atmosphere and the solar wind. While the energy involved in a jet-like event is smaller than that of "nominal" solar flares and Coronal Mass Ejections (CMEs), jets share many common properties with these major phenomena, in particular, the explosive magnetically driven dynamics. Studies of jets could, therefore, provide critical insight for understanding the larger, more complex drivers of the solar activity. On the other side of the size-spectrum, the study of jets could also supply important clues on the physics of transients close or at the limit of the current spatial resolution such as spicules. Furthermore, jet phenomena may hint to basic process for heating the corona and accelerating the solar wind; consequently their study gives us the opportunity to attack a broad range of solar-heliospheric problems.

2.
Asian-Australas J Anim Sci ; 25(4): 479-85, 2012 Apr.
Article in English | MEDLINE | ID: mdl-25049588

ABSTRACT

In order to develop methods that would enlarge the feed resources in Tibet, mixtures of hulless-barley straw and tall fescue were ensiled with four levels (0, 10%, 20%, and 30% of fresh weight) of wet hulless-barley distillers' grains (WHDG). The silos were opened after 7, 14 or 30 d of ensiling, and the fermentation characteristics and nutritive quality of the silages were analyzed. WHDG addition significantly improved fermentation quality, as indicated by the faster decline of pH, rapid accumulation of lactic acid (LA) (p<0.05), and lower butyric acid content and ammonia-N/total N (p<0.05) as compared with the control. These results indicated that WHDG additions not only effectively inhibited the activity of aerobic bacteria, but also resulted in faster and greatly enhanced LA production and pH value decline, which restricted activity of undesirable bacteria, resulting in more residual water soluble carbohydrates (WSC) in the silages. The protein content of WHDG-containing silages were significantly higher (p<0.05) higher than that of the control. In conclusion, the addition of WHDG increased the fermentation and nutritive quality of straw-grass silage, and this effect was more marked when the inclusion rate of WHDG was greater than 20%.

3.
Ultramicroscopy ; 112(1): 53-60, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22088508

ABSTRACT

The imaging properties of bright field and annular dark field scanning confocal electron microscopy (BF-SCEM and ADF-SCEM) are discussed based on their point spread functions (PSFs) in comparison with multislice simulations. Although the PSFs of BF-SCEM and ADF-SCEM show similar hourglass shapes, their numerical distributions are quite different: BF-SCEM PSF is always positive and shows a center of symmetry whereas the ADF-SCEM PSF is complex and has Hermitian symmetry. These PSF properties explain the large elongation effect in BF-SCEM for laterally extended object and almost no-elongation in ADF-SCEM, illustrating the importance of the numerical analysis of PSFs. The Hermitian symmetry of the ADF-SCEM PSF results in an interesting "edge enhancement effect" at the interface. Simulation using the PSF and the multislice method verified this effect at GaAs surfaces and InAs interfaces embedded in GaAs. This unique feature of ADF-SCEM can potentially be useful for depth sectioning. It is also pointed out that a PSF imaging model cannot be applicable for BF-SCEM of a phase object, when the system is symmetric and aberration free.

4.
Osteoarthritis Cartilage ; 19(4): 435-8, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21262369

ABSTRACT

Brother of CDO (BOC) is a cell surface receptor that derives its name from the structurally related protein, cell adhesion molecule-related/down-regulated by oncogenes (CDO, sometimes CDON). High levels of BOC mRNA and protein expression have been described in embryonic tissues with active cell proliferation and ongoing cellular differentiation(1,2). A microarray-based screen of RNA isolated from 11 different adult equine tissues unexpectedly identified BOC as having an expression pattern restricted to articular cartilage. The objective of this study was to further investigate BOC expression in adult articular cartilage relative to other tissues. Both RT-qPCR and mRNA sequencing confirmed the microarray data. Steady state BOC mRNA levels in articular cartilage were substantially higher than in the other adult tissues tested, neonatal tendon, placenta, and whole embryo. The expression of BOC displayed a pattern of tissue specificity comparable to well established cartilage matrix protein biomarkers. BOC mRNA levels in articular cartilage increased with age, but were rapidly down-regulated when chondrocytes were enzymatically isolated from the cartilage matrix and expanded in monolayer culture. Relative expression patterns of CDO were broadly similar, but displayed lower fold change differences. A functional role in articular cartilage that involves Hedgehog signaling is suggested by the known binding affinity of BOC for all three Hedgehog ligands. These data also extend BOC and CDO biology to a post-mitotic and highly differentiated cell type within a mature tissue.


Subject(s)
Cartilage, Articular/metabolism , Receptors, Cell Surface/metabolism , Animals , Cartilage, Articular/embryology , Horses , Microarray Analysis , RNA, Messenger/metabolism
5.
Ultramicroscopy ; 111(1): 20-6, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21111263

ABSTRACT

Imaging properties of scanning confocal electron microscopy (SCEM) were studied by calculating simple model systems using the multislice method. A simple geometrical explanation was given, particularly for the difference between bright field (BF) and annular dark field (ADF) SCEM. It is demonstrated that the BF-SCEM image contrast consists of two features. One gradually changes over a wide defocus range and depends on the lateral size of the object. Another appears only near the focus and is independent of sample size. On the contrary, ADF-SCEM image contrast does not depend on the lateral size of the object. Therefore, the ADF-SCEM will provide more readily interpretable image contrast.

6.
Nanotechnology ; 20(42): 425305, 2009 Oct 21.
Article in English | MEDLINE | ID: mdl-19779232

ABSTRACT

A sensitive nanosized molybdenum oxide (MoO(x)) photodetector is manufactured at a desired position by electron-beam-induced deposition (EBID). As-deposited MoO(x) had a conductivity approximately 300 S cm(-1). After 2 h annealing at 573 K, the conductivity of nanowires decreased 10 times to approximately 30 S cm(-1) and MoO(x) had photoconductivity. Nanosized MoO(x) wires enhanced the sensitivity of optical devices due to an increased surface area to volume ratio.

7.
Nanotechnology ; 20(2): 025703, 2009 Jan 14.
Article in English | MEDLINE | ID: mdl-19417284

ABSTRACT

Nanoisland films prepared by annealing thin gold films at high temperatures were imaged using scanning electron microscopy (SEM) and atomic force microscopy, and optically characterized through absorption spectroscopy. Thin gold films of effective thicknesses 2, 5 and 7 nm annealed at 500, 700 and 900 degrees C were fabricated and studied experimentally. The measured absorption characteristics in support of theoretical calculations showed that the shapes of gold islands were partial spheres. The position of the peak absorption wavelength measured with s-polarized light or at normal incidence confirmed that the island shape grew from a near-hemisphere towards a sphere with increasing annealing temperature. The SEM images confirmed that the size of islands increased from 15 nm in diameter to 40 nm in diameter as film thickness increased from 2 to 5 nm. The affect of the index of the substrate material on absorption characteristics were also studied by comparing the absorption spectra of gold island films on quartz and LaSF15 glass substrates. The use of gold nanoisland films for preparing localized surface plasmon resonance substrates was suggested as they held advantages over the gold colloid films.

8.
Ultramicroscopy ; 108(9): 981-8, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18519159

ABSTRACT

An efficient, Bloch wave-based method is presented for simulation of high-resolution scanning confocal electron microscopy (SCEM) images. The latter are predicted to have coherent nature, i.e. to exhibit atomic contrast reversals depending on the lens defocus settings and sample thickness. The optimal defocus settings are suggested and the 3D imaging capabilities of SCEM are analyzed in detail. In particular, by monitoring average image intensity as a function of the probe focus depth, it should be possible to accurately measure the depth of a heavy-atom layer embedded in a light-element matrix.

9.
Science ; 318(5856): 1580-2, 2007 Dec 07.
Article in English | MEDLINE | ID: mdl-18063786

ABSTRACT

Coronal magnetic fields are dynamic, and field lines may misalign, reassemble, and release energy by means of magnetic reconnection. Giant releases may generate solar flares and coronal mass ejections and, on a smaller scale, produce x-ray jets. Hinode observations of polar coronal holes reveal that x-ray jets have two distinct velocities: one near the Alfvén speed ( approximately 800 kilometers per second) and another near the sound speed (200 kilometers per second). Many more jets were seen than have been reported previously; we detected an average of 10 events per hour up to these speeds, whereas previous observations documented only a handful per day with lower average speeds of 200 kilometers per second. The x-ray jets are about 2 x 10(3) to 2 x 10(4) kilometers wide and 1 x 10(5) kilometers long and last from 100 to 2500 seconds. The large number of events, coupled with the high velocities of the apparent outflows, indicates that the jets may contribute to the high-speed solar wind.

10.
Conf Proc IEEE Eng Med Biol Soc ; 2006: 4936-40, 2006.
Article in English | MEDLINE | ID: mdl-17946662

ABSTRACT

A system with an optical 6-axis force sensor was developed to measure contact force during braille reading. In using this system, we encountered two problems. One is a variability of output values depending on the contact point. This was solved by using two transformation techniques. The other is that subjects read braille in a different manner from the usual. We compared two manners of braille reading, one-handed vs two-handed, and found a small reduction in reading speed. Using this system, we collected data from four braille readers and quantitatively showed more minute contact force trajectories than those in earlier studies.


Subject(s)
Blindness/rehabilitation , Sensory Aids , Adolescent , Adult , Algorithms , Aluminum/chemistry , Calibration , Equipment Design , Female , Humans , Male , Middle Aged , Stress, Mechanical , Time Factors , Touch
11.
Ultramicroscopy ; 103(1): 17-22, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15777596

ABSTRACT

The effect of the accelerating voltage of incident electrons on the resolution of electron-beam-induced deposition was investigated by a dynamic Monte Carlo profile simulator which includes the electron scattering in the already grown deposit structure. By simulating the deposition at two different accelerating voltages of 20 and 200 kV with an idealistic zero-diameter incident probe on a bulk substrate, it was revealed that the smaller size structures were attainable by 200 keV than by 20 keV. The effect of the substrate was also argued by comparing the above results with the simulation results obtained for a point-like starting substrate. Surprisingly, the shapes of the deposits grown on bulk substrates were reproduced well by the simulations starting from point-like substrates indicating the small effect of the substrate on the shape of deposits.

12.
J Microsc ; 214(Pt 1): 76-9, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15049871

ABSTRACT

Electron beam-induced deposition was carried out using a scanning transmission electron microscope with a field emission gun to fabricate nanometre-sized structures. A small amount of a metal-organic gas was introduced near the substrate in the microscope chamber, and focused electron beams were irradiated. Two- and three-dimensional structures were fabricated by scanning the beam position. The minimum line width of the freestanding structures was 8 nm at a constant gas flux used. This line width of 8 nm is considered to be achieved by employing a high accelerating voltage, which leads to a small probe size, and the optimum scanning speed.


Subject(s)
Imaging, Three-Dimensional/instrumentation , Imaging, Three-Dimensional/methods , Microscopy, Electron/instrumentation
13.
J Hepatobiliary Pancreat Surg ; 8(5): 473-8, 2001.
Article in English | MEDLINE | ID: mdl-11702259

ABSTRACT

Most gastroenteropancreatic neuroendocrine tumors contain high-affinity binding sites for somatostatin, and somatostatin-receptor scintigraphy has been introduced for the in-vivo evaluation of such tumors. We report two patients with gastroenteropancreatic neuroendocrine tumors, in whom it was quite difficult to localize the tumors by conventional techniques, and in whom we found that (111)In-DTPA-pentetreotide scintigraphy was useful for accurate information on tumor localization. In the first patient, who had gastrinoma, multiple tumors were shown in the gastrinoma triangle, but we could not clarify whether there were any tumors in the pancreatic body. The selective arterial secretin injection (SASI) test diagnosed that the gastroduodenal artery was the feeder of the gastrinomas, and (111)In-DTPA-pentetreotide scintigraphy with single-photon emission computed tomography indicated the absence of tumors in the pancreatic body. In the second patient, who had insulinoma, multiple liver tumors and a large mass in the hilum of the spleen were shown. (111)In-DTPA-pentetreotide scintigraphy was useful in determining that there was no secretion of insulin from the tumor in the hilum of the spleen. In conclusion, X-ray computed tomography is superior for detection of neuroendocrine tumors, because not all neuroendocrine tumors have somatostatin receptors; however, somatostatin receptor scanning, as well as the SASI test, may be useful for the surveillance of patients with known primary tumors, for monitoring patients with disseminated disease, and for following the treatment of these patients.


Subject(s)
Gastrointestinal Neoplasms/diagnostic imaging , Indium Radioisotopes , Neuroendocrine Tumors/diagnostic imaging , Pancreatic Neoplasms/diagnostic imaging , Pentetic Acid , Somatostatin , Tomography, Emission-Computed, Single-Photon , Adult , Aged , Diagnosis, Differential , Humans , Male , Somatostatin/analogs & derivatives
14.
Intern Med ; 40(8): 747-50, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11518116

ABSTRACT

We report a case in which pituitary apoplexy developed shortly after an intravenous (i.v.) injection of luteinizing hormone-releasing hormone (LH-RH). A 56-year-old man with prolactin-producing pituitary tumor complained of severe headache, visual field loss and facial nerve palsy shortly after LH-RH test. Magnetic resonance image (MRI) revealed a hemorrhage in the pituitary adenoma. He showed dramatic improvement in his symptoms after decompression surgery. These findings suggest a causal relationship between the i.v. injection of LH-RH and pituitary apoplexy. Possible pituitary apoplexy should be kept in mind during pituitary testing.


Subject(s)
Gonadotropin-Releasing Hormone/adverse effects , Pituitary Apoplexy/chemically induced , Pituitary Neoplasms/diagnosis , Prolactinoma/diagnosis , Facial Paralysis/etiology , Gonadotropin-Releasing Hormone/administration & dosage , Gonadotropins, Pituitary , Headache/etiology , Hormones/blood , Humans , Injections, Intravenous , Magnetic Resonance Imaging , Male , Middle Aged , Pituitary Apoplexy/blood , Pituitary Apoplexy/complications , Pituitary Apoplexy/diagnosis , Vision Disorders/etiology
15.
J Clin Endocrinol Metab ; 86(6): 2728-33, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11397878

ABSTRACT

One of the defining biochemical features of Cushing's disease is a relative insensitivity to glucocorticoid (GC) feedback, but an analysis of the GC receptor has failed to detect any major abnormalities. However, two isoenzymes of 11 beta-hydroxysteroid dehydrogenase (11 beta HSD), either by converting cortisone (E) to cortisol (F) (type 1) or conversely by converting F to E (type 2), play an important prereceptor role in regulating corticosteroid hormone action at several sites. 11 beta HSD1 and -2 expression within the anterior pituitary gland itself may modulate GC feedback at an autocrine level, and we have speculated that this may be deranged in Cushing's disease. Detection of 11 beta HSD type 1 and 2 immunoreactive protein was performed using fluorescence immunohistochemistry. Double immunofluorescent studies were undertaken on normal pituitary to define the cellular localization of 11 beta HSD isoenzymes using antisera against GH, ACTH, LH, FSH, PRL, and S100, a nonhormonal marker of folliculo-stellate cells. In normal pituitary, positive staining for 11 beta HSD1-immunoreactive protein was observed in GH- and PRL-secreting cells and in folliculo-stellate cells; gonadotrophs, thyrotrophs, and ACTH-positive cells were negative. 11 beta HSD2 immunoreactivity was absent in all cell types. RT-PCR detected 11 beta HSD1 messenger ribonucleic acid (mRNA) expression in the normal pituitary; 11 beta HSD2 mRNA expression was also seen in most normal tissue. By contrast, in ACTH-secreting adenomas 11 beta HSD2 immunostaining was strongly positive in every case of corticotroph adenoma. 11 beta HSD1 immunoreactivity was also observed occasionally, but to a much lesser extent. In other pituitary tumors, both functional and nonfunctional, 11 beta HSD expression was variable in terms of isoenzyme mRNA and intensity of protein staining. The expression of 11 beta HSD1 (which generates F from E) in somatotrophs and lactotrophs suggests an autocrine role for this isoenzyme in the glucocorticoid regulation of pituitary GH and PRL secretion. 11 beta HSD2 expression is markedly induced in ACTH-secreting pituitary tumors and, by converting F to E, may explain the resetting of glucocorticoid feedback control in Cushing's disease.


Subject(s)
Adrenocorticotropic Hormone/metabolism , Hydroxysteroid Dehydrogenases/metabolism , Isoenzymes/metabolism , Pituitary Neoplasms/enzymology , Pituitary Neoplasms/metabolism , 11-beta-Hydroxysteroid Dehydrogenases , Adolescent , Adult , Aged , Aged, 80 and over , Female , Fluorescent Antibody Technique , Humans , Male , Middle Aged , Reference Values , Tissue Distribution
18.
Physiol Behav ; 72(1-2): 287-9, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11240008

ABSTRACT

The effect of intracerebroventricular injection of corticotropin-releasing factor (CRF) on various behaviors in chicks was determined at 15-min intervals over a 30-min period. Food intake of chicks was significantly decreased, and pecking rhythm was significantly delayed by CRF during the first 15-min post-injection. The similar tendencies were observed in the second 15-min post-injection, but not significantly different. Stepping, as an indicator of locomotion, was not different at 15-min post-injection, but was increased by CRF, thereafter. These results suggest that CRF acts within the central nervous system to decrease food intake and increase locomotion in the chick.


Subject(s)
Chickens/physiology , Corticotropin-Releasing Hormone/pharmacology , Feeding Behavior/drug effects , Motor Activity/drug effects , Animals , Animals, Newborn , Corticotropin-Releasing Hormone/administration & dosage , Eating/drug effects , Injections, Intraventricular , Male
19.
J Biol Chem ; 276(16): 13121-6, 2001 Apr 20.
Article in English | MEDLINE | ID: mdl-11145971

ABSTRACT

The transcription factor neuron-restrictive silencer factor/repressor element-1 (RE-1) silencing transcription factor (NRSF/REST) contains nine zinc finger domains and binds to the DNA element, neuron-restrictive silencer element/repressor element-1. REST4, a C-terminally truncated form of NRSF/REST, contains the five N-terminal zinc fingers and binds weakly to DNA yet is transported into the nucleus. To study the contribution of zinc fingers 6-8 to DNA binding, each was mutated. A mutation in zinc finger 6 or 8 had little effect; however, mutation of zinc finger 7 diminished DNA binding. Mutations in any two of these zinc fingers eliminated DNA binding. The contribution of zinc fingers 2-5 to nuclear targeting was studied. Deletion of zinc finger 5 prevented nuclear targeting. Mutations in zinc finger 2, 4, or 5 did not abolish nuclear targeting. However, a zinc finger 3 mutation together with a zinc finger 2 mutation localized to the nuclear envelope. A zinc finger 3 mutation alone or in combination with a zinc finger 4 or 5 mutation produced a punctate nuclear distribution. These results suggest the presence of signals for nuclear targeting, for nuclear entry, and for release from the translocation machinery within zinc fingers 2-5 of REST4.


Subject(s)
Cell Nucleus/metabolism , DNA/metabolism , Repressor Proteins/chemistry , Repressor Proteins/metabolism , Transcription Factors/chemistry , Transcription Factors/metabolism , Base Sequence , Binding Sites , Cell Line , DNA/chemistry , DNA Primers , Green Fluorescent Proteins , Humans , Luminescent Proteins/analysis , Molecular Sequence Data , Mutagenesis , Recombinant Fusion Proteins/analysis , Recombinant Fusion Proteins/metabolism , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Sequence Deletion , Templates, Genetic , Transfection , Zinc Fingers , beta-Galactosidase/analysis
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