• 천문학회지
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• 제50권5호
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• pp.151-155
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• 2017

We investigate the radio properties of the dwarf galaxy SDSS J133245.62+263449.3 which shows optical signatures of black hole activity. Dwarf galaxies are known to host intermediate mass black holes (IMBHs) with masses $M_{BH}{\sim}10^{4-6}M_{\odot}$, some of them being radio loud. Recently, Reines et al. (2013) found dwarf galaxy candidates which show signatures of being black hole hosts based on optical spectral lines. SDSS J133245.62+263449.3 is one of them; it shows a flux density of ~ 20 mJy at 1.4 GHz, which corresponds to $L_{1.4GHz}{\sim}10^{23}W\;Hz^{-1}$. This is much brighter than other black hole host dwarf galaxies. However, star formation activity can contribute to radio continuum emission as well. To understand the nature of the radio emission from SDSS J133245.62+263449.3, we imaged this radio loud dwarf galaxy at low frequencies (325 MHz and 610 MHz) using the Giant Metrewave Radio Telescope (GMRT). We present here the high resolution images from our GMRT observations. While we detect no obvious extended emission from radio jets from the central AGN, we do find the emission to be moderately extended and unlikely to be dominated by disk star formation. VLBI observations using the Korean VLBI Network (KVN) are now being planned to understand the emission morphology and radiation mechanism.

• Structural Engineering and Mechanics
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• 제66권3호
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• pp.343-351
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• 2018

Brazilian disc test is one of the most widely used experiments in the literature of geo-mechanics. In this work, the pre-holed concrete Brazilian disc specimens are numerically modelled by a two-dimensional discrete element approach. The cracks initiations, propagations and coalescences in the numerically simulated Brazilian discs (each containing a single cylindrical hole and or multiple holes) are studied. The pre-holed Brazilian discs are numerically tested under Brazilian test conditions. The single-holed Brazilian discs with different ratios of the diameter of the holes to that of the disc radius are modelled first. The breakage load in the ring type disc specimens containing an internal hole with varying diameters is measured and the crack propagation mechanism around the wall of the ring is investigated. The crack propagation and coalescence mechanisms are also studied for the case of multi-holes' concrete Brazilian discs. The numerical and experimental results show that the breaking mechanism of the pre-holed disc specimens is mainly due to the initiation of the radially induced tensile cracks which are growth from the surface of the central hole. Radially cracks propagated toward the direction of diametrical loading. It has been observed that for the case of disc specimens with multiple holes under diametrical compressive loading, the breaking process of the modelled specimens may occur due to the simultaneous cracks propagation and cracks coalescence phenomena. These results also show that as the hole diameter and the number of the holes increases both the failure stress and the crack initiation stress decreases. The experimental results already exist in the literature are quit agree with the proposed numerical simulation results which validates this simulation procedure.

• 천문학회보
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• 제40권1호
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• pp.78.2-78.2
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• 2015

Powered by a supermassive black hole, active galactic nuclei (AGNs) are characterized by prominent emission lines including Blamer lines. The unification scheme of AGNs requires the existence of a thick molecular torus that may hide the broad emission line region. In this configuration, it is expected that the far UV radiation from the central engine can be Raman scattered by neutral hydrogen to reappear around Balmer lines which can be identified observationally with broad Balmer wings. Another mechanism that can form Balmer wings is considered by invoking a fast moving medium around the central engine. In this presentation, we produce Balmer wings that are formed through Raman scattering and also those expected from a fast moving emission flow. It is noted that Raman Balmer wings exhibit stronger red part whereas the opposite behavior is seen in the Balmer wings obtained from a fast moving emission flow.

• Advances in Traditional Medicine
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• 제8권4호
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• pp.448-451
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• 2008

Picrorhiza kurrooa Royle. is a well known medicinal plant among the indigenous medical practitioners of India. Present study is the first time to report the activity on the central nervous system. Preliminary study of the hot water extract showed significant depressant activity on the hole board test as evidenced from the ambulation and head dipping scores. The extract showed better activity compared to diazepam on the duration of pentobarbital induced sleeping time.

• 대한자기공명의과학회:학술대회논문집
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• 대한자기공명의과학회 2001년도 제6차 학술대회 초록집
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• pp.113-113
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• 2001

Purpose： In the gradient echo EPI the conventional T2＊-weighted image is poor in signal as well distorted by the field inhomogeneity. By acquiring a proton density image in addition to th T2＊-weighted image at the same scan, the fMRI processing can be improved. Method： The central region of the k space is acquired twice at different time points after th RF pulse while acquiring the other regions onc as described in Fig. 1. In Fig. 1 the segment numbers are chronological. Then, we can get two images of different contrast by interleaving th central region in the k space as done in the dua contrast FSE.

• Advances in Traditional Medicine
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• 제6권3호
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• pp.215-220
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• 2006

The Sundarbans mangrove forest has a rich biodiversity of flowering plants and many of these have been used in traditional medicine although the flora remains comparatively uninvestigated scientifically. Xylocarpus granatum, Xylocarpus moluccensis and Excoecaria agallocha methanolic extract showed a central nervous system depressant activity on the hole cross and open field test at 800 mg/kg dose level. The most significant depressant activity was observed in Xylocarpus granatum followed by Xylocarpus moluccensis and Excoecaria agallocha. There was no depressant activity observed in the models for Sarcolobus globosus. Further studies are required to confirm the activity and to explain the mechanism.

• Advances in Traditional Medicine
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• 제10권2호
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• pp.86-89
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• 2010

Two common Indian spices Carum copticum Karst (ajowan) and Cinnamomum tamala T.Nees. (bay leaves) has been investigated first time to report the activity on the central nervous system. Preliminary study of the hot water extract showed depressant activity on the hole board test as evidenced from the ambulation and head dipping scores. The extracts further quicken the onset and increased the duration of pentobarbital induced sleeping time.

• 천문학논총
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• 제30권2호
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• pp.417-421
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• 2015

We analyzed 0.5-45 keV data of NGC 3227 observed by Suzaku six times between 2008 October 28 and December 2. The count-count plot between the 0.5-3 keV and 3-10 keV bands exhibits a clear break, separating the data into bright and faint phases. Applying the difference spectrum method and time-averaged spectral fits to the phase data, we found the presence of two kinds of variable primary X-rays, (1) a hard primary component with ${\Gamma}{\sim}1.7$ dominating in the faint phase and (2) a soft primary continuum with ${\Gamma}{\sim}2.4$ appearing in the bright phase, both affected by partial absorption. Considering their timing and spectral characteristics, component (1) is presumably identical to a Compton continuum in the low/hard state, while component (2) may correspond to the hard tail emission in the high/soft state, or compact-jet emission. In that case, an accretion ow onto the central super massive black hole in NGC 3227 can be interpreted to include the two different states.

• Structural Engineering and Mechanics
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• 제84권4호
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• pp.453-464
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• 2022

Thin plates are the most common spatially stressed members in engineering structures that bear out-of-plane loads. Therefore, it is of great significance to study the deformation performance characteristics of thin plates for structural design. By constructing 12 basic displacement and deformation basis vectors of the four-node square thin plate element, a deformation decomposition method based on the complete orthogonal mechanical basis matrix is proposed in this paper. Based on the deformation decomposition method, the deformation properties of the thin plate can be quantitatively analyzed, and the areas dominated by each basic deformation can be visualized. In addition, the method can not only obtain more deformation information of the structure, but also identify macroscopic basic deformations, such as bending, shear and warping deformations. Finally, the deformation properties of the bidirectional thin plates with different sizes of central holes are analyzed, and the changing rules are obtained.

• Advances in Traditional Medicine
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• 제6권1호
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• pp.21-26
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• 2006

The ethanolic extract of Fleurya interrupta Gaud, (Urticaceae) was tested for its possible neuropharmacological effects on experimental animals, For the primary neuropharmacological screening of this plant, the ethanolic extract of its aerial parts was subjected to preliminary evaluation for acute toxicity, antinociceptive activity and central nervous system (CNS) activities. At the doses of 125 and 250 mg/kg, the extract significantly (P < 0.01 and P < 0. 001) and dose-dependently increased the frequency of acetic acid induced writhing in mice. In the pentobarbitone induced sleeping time test, the extract at the above dose levels, significantly and dose-dependently decreased the pentobarbitone induced sleeping time (P < 0.001) and increased the time for onset of sleep (P < 0.001) in mice. In the open field and hole cross tests, test animals showed an increase in their movement in the both tests from the 2nd observation period (30 min) and persisted throughout the entire experimental period (240 min). These results of the extract may attribute a stimulating action on the CNS. On the basis of these findings, it can be assumed that the extract exerts its stimulating effect on the CNS in mice by interfering with the cortical function or increasing the effect of some CNS stimulating neurotransmitters.