183 research outputs found
Chromium isotopic composition of some chondritic meteorites
The Cr isotopic composition of primitive meteorites (acid-residue fractions) was studied. Five chondrites were analyzed in this work [Allende (CV3), Murchison (CM2), Nuevo Mercurio (H5), La Criolla (L6), Qingzhen (EH3)]. Although in most samples, no isotopic anomalies beyond the experimental errors could be detected, an elevated ^Cr/^Cr ratio was found in the acid-soluble fraction from Qingzhen. Moreover, ε^Cr and ε^Cr show an inverse correlation among the meteorites analyzed in this study, and the acid residues have larger ε^Cr and smaller ε^Cr values than do the acid-soluble fractions in Allende and Murchison. The enrichment of ^Cr in the Qingzhen sample suggests that the ^Cr heterogeneity due to stellar nucleosynthesis has remained in enstatite chondrite as well as carbonaceous chondrite. In addition, the inverse correlation of ε^Cr and ε^Cr detected in acid residue samples indicates that the high-temperature condensate contained more exotic ^Cr. It is also suggested that the homogenization of Cr isotopes proceeded with time, and terminated within a relatively short time scale of less than 2-3 Ma
Distribution of Fodrin in the Keratinocyte In Vivo and In Vitro
Distribution of fodrin in the keratinocyte, both in vivo and in vitro, was examined by immunofluorescence microscopy. In the rat epidermis in vivo, fodrin was localized in the cell periphery of the spinous layer of all the skins studied. In only the basal layer of the thick skin, however, fodrin was seen intensely in the cytoplasm. As in vitro keratinocytes, a mouse cell line (Pam 212) cultured in low (0.06 mM) as well as standard (1.87 mM) Ca2+ was examined. In low Ca2+, fodrin was observed throughout the cytoplasm without marked accumulation irrespective of the cell density. The cytoplasmic labeling in low Ca2+ looked filamentous and became aggregated when cells were treated with cytochalasin B; at least some of the aggregates coexisted with those of F-actin. In contrast, fodrin distribution was not affected with colchicine. On the other hand, in standard Ca2+, the protein became concentrated along the cell periphery and less conspicuous in the cytoplasm as the cells reached confluency. When cells were transferred from low to standard Ca2+, the distribution of fodrin changed accordingly within 180min. The present results indicate that fodrin in the keratinocyte is likely to be associated with actin filaments and that it takes two different ways of distribution both in vivo and in vitro. The peripheral and the cytoplasmic labeling of in vivo and in vitro cells are likely to correspond. It may be that fodrin changes its localization according to the cell's proliferative activity
Tertiary Formations in the Environs of Yuya-wan, Yamaguchi Prefecture
The Cenozoic formations developed in the "Yuya-wan area", Yamaguchi Prefecture are subdivided as shown in the following table.
In this article the writers gave the description of the Tertiary stratigraphy and structure in the area, and tried to make the correlation among the Tertiary formations in this area, the North Kyushu, and the San-in district with one another.
[Original table is skipped. For more details, please refer to the full text.
Recognition for Objects by Relationships Between Attributes
Object recognition methods based on attributes have been studied. Conventional methods recognize objects by the presence or absence of attributes. However, the conventional methods have two problems. Firstly, the conventional methods are not able to recognize a target object of which a part of attributes is occluded. Secondly, the conventional methods miss-recognize a target object, which has irrelevant attributes. Therefore, to solve these two problems, we propose the object recognition by relationships between attributes. In this paper, we focus on the face as the recognition object. The proposed method uses relationships as constraints for object recognition using attributes. The proposed method applies two major type constraints. The first constraint is a local constraint, which is applied to a part of attributes. To achieve robust face recognition against occlusion scenes, the proposed method uses the local constraint. And then, the second constraint is a global constraint, which is applied to all attributes. To achieve robust face recognition against irrelevant attributes, the proposed method uses the global constraint. In this paper, to evaluate the effectiveness of the proposed method, we compared the proposed method with a conventional method. We experimented in normal face, occlusion and irrelevant attributes. We used 2580 images of a face which are changed in scale and rotation. Experimental results showed that the recognition ratio of the proposed method is equal to or more than that of the conventional method in normal face, occlusion, and irrelevant attributes
Path Integral for Space-time Noncommutative Field Theory
The path integral for space-time noncommutative theory is formulated by means
of Schwinger's action principle which is based on the equations of motion and a
suitable ansatz of asymptotic conditions. The resulting path integral has
essentially the same physical basis as the Yang-Feldman formulation. It is
first shown that higher derivative theories are neatly dealt with by the path
integral formulation, and the underlying canonical structure is recovered by
the Bjorken-Johnson-Low (BJL) prescription from correlation functions defined
by the path integral. A simple theory which is non-local in time is then
analyzed for an illustration of the complications related to quantization,
unitarity and positive energy conditions. From the view point of BJL
prescription, the naive quantization in the interaction picture is justified
for space-time noncommutative theory but not for the simple theory non-local in
time. We finally show that the perturbative unitarity and the positive energy
condition, in the sense that only the positive energy flows in the positive
time direction for any fixed time-slice in space-time, are not simultaneously
satisfied for space-time noncommutative theory by the known methods of
quantization.Comment: 21 page
Transcutaneous Electrical Retinal Stimulation Therapy for Age-Related Macular Degeneration
This reports the preliminary outcome of a transpalpebral electrical retinal stimulation therapy for age-related macular degeneration (ARMD)
CORONARY ARTERY MORPHPLOGY AND REACTIVITY TO ACUTE HYPOXIA IN CHRONIC PULMONARY DISEASE
In patients with chronic pulmonary disase (CPD), myocardial infarction is rare. To elucidate why this is so, we investigated the morphological changes and the reactivity of the coronary artery to acute hypoxia in patients with CPD. Sixty patients with CPD and 28 normal subjects were studied. Measurements of pulmonary homodynamics and coronary angiography were undertaken before and after inhalation of 13%O2 for 15 minutes. The size of the coronary arteries was measured using a densitometric method, and a coronary narrowing score was calculated according to the WHO criteria. The size of the left anterior descending artery of patients with low %VC and hypoxia was larger than that of the normal subjects. In patients with CPD, the coronary narrowing score was low and the atherosclerotic change was minimal. The reactivity of the coronary arteries to acute hypoxia was reduced in patients with CPD when compared with normal subjects
Holographic Penta and Hepta Quark State in Confining Gauge Theories
We study a new embedding solutions of D5 brane in an asymptotic
AdS space-time, which is dual to a confining gauge
theory. The D5 brane is wrapped on as in the case of the vertex of
holographic baryon. However, the solution given here is different from the
usual baryon vertex in the point that it couples to -anti-quarks and
quarks on the opposite two points of , the north and south poles,
respectively. The total quark number of this state is preserved as when
minus one is assigned to anti-quark, then it forms a color singlet like the
baryon. However, this includes anti-quarks and quarks, whose number is larger
than that of the baryon. When we set as , we find the so called penta
and hepta-quark states. We study the dynamical properties of these states by
solving the vertex and string configurations for such states. The mass spectra
of these states and the tension of the stretched vertex are estimated, and they
are compared with that of the baryon.Comment: 24 pages, 6 figure
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