High-Resolution Magnetic Force Microscopy Using Carbon Nanotube Probes Fabricated Directly by Microwave Plasma-Enhanced Chemical Vapor Deposition

Carbon nanotubes (CNTs) have been successfully grown on the tip apex of an atomic force microscopy (AFM) cantilever by microwave plasma-enhanced chemical vapor deposition (MPECVD). Both scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations reveal that the diameter of the CNTs is ∼30 nm and the magnetic particles with diameter of ∼20 nm, which was used as catalyst for the CNT growth, exist on the top. This CNT probe has been applied to magnetic force microscopy (MFM) on the ultrahigh-density magnetic recording media with 1200 kilo flux change per inch (kfci)

Visible and near-infrared reflectance spectroscopy of the Yamato 980459 meteorite in comparison with some shergottites

Visible and near-infrared reflectance spectrum of a sample of Yamato (Y) 980459 meteorite has been measured. Preliminary analyses of the spectrum have been performed using the modified Gaussian model, and the results have been compared with those of similar analyses of some shergottites and tricomponent mixtures of olivine, pyroxene, and plagioclase. They suggest that Y980459 has lower Fe and/or Ca concentration in pyroxene phase except its high-Ca pyroxene having similar Fe/Ca concentration to EETA79001 (Lithology A), lower pyroxene abundance, and more glassy phase than those shergottite samples. An estimated pyroxene modal abundance of this Y980459 sample is 36±13%, which is consistent with another estimate of 48% by an independent petrographic study

Reflectance spectra of the Yamato 000593 nakhlite: Spectroscopic similarities to other nakhlites

Y000593 (Y) is a newly found nakhlite and its component minerals are augite (～80 vol% ), olivine (～10 vol% ) and mesostasis (～10 vol% ). We compare the reflectance spectrum of Y000593 with those of two other nakhlites, Nakhla and Lafayette. The reflectance spectrum of Y000593 is similar to that of Nakhla, and is also similar to Lafayette except for differences in slope from 0.6-0.8μm in wavelength. Reflectance spectra of all these nakhlites show two strong absorption bands around 1μm and 2μm due to augite. Their band minimum wavelengths were calculated using the polynomial fitting and the modified Gaussian model (MGM). Almost all of their band centers and band parameters were similar to one another, which is consistent with the mineralogical and petrological study of nakhlites

Mineralogy and petrology of Yamato 000593: Comparison with other Martian nakhlite meteorites

Yamato (Y) 000593 is a new nakhlite recovered from Antarctica and is composed of roughly 80% augite, 10% olivine and 10% mesostasis. Augite is chemically homogeneous except for Fe-rich rims adjacent to the mesostasis. Olivine has more extensive chemical zoning, but the most Fe-rich part is also near the mesostasis. These observations suggest that chemical zoning of both augite and olivine was produced by interaction with the mesostasis. The crystallization history of Y000593 as deduced from this study is as follows. (1) Crystallization of cumulus augite and olivine and formation of symplectites in olivine. (2) Accumulation of augite and olivine. (3) Mesostasis crystallization and interaction of the augite and olivine rims with the intercumulus melt. (4) Aqueous alteration. The petrography and mineralogy of Y000593 is generally similar to other nakhlites, but minor mineralogical differences are observed. These differences resulted from different thermal histories due to different locations (burial depths) in the same cooling cumulate pile. Y000593 is most similar to Nakhla and both samples experienced similar formation histories. However, later mesostasis crystallization of Y000593 was more rapid than Nakhla due to its faster cooling rate. The burial depth of Y000593 would be shallower than 3 m from the surface, and is intermediate between NWA817 and Nakhla. The abundance and mineralogy of the mesostasis as well as augite and olivine rim compositions are related to the burial depths of nakhlites

Yamato 980459: Mineralogy and petrology of a new shergottite-related rock from Antarctica

Y980459, a new Martian meteorite from Antarctica, is composed of coarse porphyritic olivine grains (up to 2mm) set in the groundmass of olivine and pyroxene with abundant glassy mesostasis containing dendritic olivine and pyroxene. The overall petrography of Y980459 is similar to those of olivine-phyric shergottites, but the absence of plagioclase and Ca phosphates makes Y980459 unique. Because of the absence of maskelynite, Y980459 is not a shergottite if we employ the classic definition of shergottite. Both olivine and pyroxenes are extensively zoned. The most magnesian olivine composition is Fo86 and the olivine compositions are related to three different occurrence types of olivine (large phenocrysts, groundmass, and mesostasis). Pyroxenes have orthopyroxene cores (En81Fs17Wo2) mantled by pigeonite with the rims of augite. The mineralogy of Y980459 suggests that rapid crystallization of the parent magma caused significant undercooling and plagioclase did not nucleate. Probably, rapid transport of the Y980459 parent magma from the depth to the Martian surface crystallized olivine and pyroxene at first and eruption onto the surface quenched the magma producing the glassy mesostasis. Because olivine and pyroxene compositions of Y980459 are the most magnesian among Martian meteorites, Y980459 would represent one of the most primitive Martian magmas and derive from a highly reduced mantle. It seems that Y980459 contains no cumulus component, suggesting that Y980459 is a melt. In this sense, Y980459 is similar to QUE94201. The similarity in mineralogy and chemistry between Y980459 and olivine-phyric shergottites suggests derivation from a similar highly reduced mantle. However, Y980459 was the only sample that directly erupted onto the Martian surface without any accumulation processes

Evidence for receptor-mediated inhibition of intrinsic activity of GTP-binding protein, Gi1 and Gi2, but not G0 in reconstitution experiments

AbstractThe receptor-mediated inhibition of intrinsic activities of GTP-binding proteins (G-proteins) was studied. Pertussis toxin (IAP)-substrate G-protein, Gi1, Gi2 or G0, was prelabeled with [α-32P]GDP and reconstituted with synaptic membranes of the guinea pig cerebellum in the presence of 0.02% of Chaps. Intrinsic activities of G-proteins were evaluated by the release of [α-32P]GDP in exchange for added GppNHp or GDP in reconstituted preparations. U-50,488H (1 nM-10 μM), a specific ϰ-subtype of opioid receptor agonist, inhibited the [α-32P]GDP release in exchange for added 1 μM GppNHp in Gi1-reconstituted preparations in a concentration-dependent manner. On the other hand, the ϰ-opioid agonist at 10 μM increases the Km values of GppNHp, but not GDP in exchange for [α-32P]GDP release in preparations reconstituted with Gi1 or Gi2, but not with G0. These findings indicate that ϰ-opioid receptor is coupled to inhibition of intrinsic activities of Gi1 and Gi2, but not G0, in guinea pig cerebellar membranes. In addition, it was revealed that the mode of action is mediated by a decrease in affinity of GTP (or its analog) for G-proteins, but not by a change in affinity of GDP

Lamina Densa Malformation Involved in Histogenesis of Primary Localized Cutaneous Amyloidosis

Skin lesions of lichenoid amyloidosis and macular amyloidosis were immunohistochemically investigated using five monoclonal antibodies against basement membrane zone (BMZ) components. A hemidesmosomal component did not contribute to amyloid deposits, but components of the lamina densa and anchoring fibrils were associated with amyloid deposits in the uppermost dermis. Immunoelectron microscopy revealed that these BMZ components were not only aggregated in the BMZ and dermis, but were also involved in the individual amyloid islets. The lamina densa was disrupted in the interface areas just above the amyloid deposits, where cytoplasm of the basal cells directly faced the aggregate of amyloid filaments. Aggregates of some BMZ components were continuous to the amyloid islets from the lamina densa area. These findings suggest that a lamina densa malformation is involved in amyloid production in the interface of the BMZ, and support the secretion theory rather than the fibrillar body theory of amyloidogenesis in these types of primary localized cutaneous amyloidosis

Growth of Pd-Filled Carbon Nanotubes on the Tip of Scanning Probe Microscopy

We have synthesized Pd-filled carbon nanotubes (CNTs) oriented perpendicular to Si substrates using a microwave plasma-enhanced chemical vapor deposition (MPECVD) for the application of scanning probe microscopy (SPM) tip. Prior to the CVD growth, Al thin film (10 nm) was coated on the substrate as a buffer layer followed by depositing a 5∼40 nm-thick Pd film as a catalyst. The diameter and areal density of CNTs grown depend largely on the initial Pd thickness. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images clearly show that Pd is successfully encapsulated into the CNTs, probably leading to higher conductivity. Using optimum growth conditions, Pd-filled CNTs are successfully grown on the apex of the conventional SPM cantilever

Ruptured basilar artery aneurysm causing isolated bilateral abducens nerve palsy

症例は54歳，女性。頭痛を伴わない回転性めまいで発症し，診察時には両側外転神経麻痺症状のみ認められた。CT でくも膜下出血，特にprepontine cistern に厚い血腫が認められ，MRA では脳底動脈瘤が認められた。破裂脳動脈瘤に対して，コイル塞栓術を施行した。術後，新たな神経学的異常所見は認められなかった。両側神経麻痺は発症から４か月後に完全回復が得られた。外転神経麻痺には幾つかの機序が挙げられている。動脈瘤の直接的な圧迫，脳浮腫や脳内出血による頭蓋内圧の亢進，外転神経核への栄養血管の攣縮などである。本症例ではprepontine cistern に限局した血腫による圧迫が影響して両側外転神経麻痺のみで発症したと考えられたA 54-year-old woman presented withdsudden vertigo without headache. Upon admission, neurological examination revealed isolated bilateral abducens nerve palsn. Computed tomography revealed subarachnoid haemorrhage, particularly aythick haematoma, in the prepontine cistern. Magnetic resonanceAangiography）showed a ruptured basilar artery aneurysm. Endovascular coil embolization was performed for this ruptured aneurysm. Postoperatively, no new neurological deficits were observed. Bilateral abducens nerve palsy recovered and disappeared 4 months after onset.sSeveral possible mechanisms can explain the occurrence of abducens nerve palsy, including the following: a direct mass effect of the aneurysmton the abducens nerve, increased intracranial pressure induced by brain swelling or parenchymal haemorrhage, and a vasospasm of thc pontine branch of the basilar artery supplying the abducens nuclei. In this case, we speculated that the isolated bilateral abducens nerve palsy was caused by compression of the local haematoma in the prepontine cistern secondary to a ruptured basilar artery aneurysm

ヘイケイキ イゴ ノ ジョセイ ノ コツソショウショウ シンダン ニ オヨボス BMI ノ エイキョウ ニ ツイテ

This study demonstrates that BMI has an influence on diagnosis of osteoporosis in menopausal and post-menopausal women, and that the prevalence rate of osteoporosis can be easily estimated from the BMI value of each patient