scholarly journals CYTOPLASMIC PARTICLES AND AMINOACYL TRANSFERASE I ACTIVITY

1970 ◽  
Vol 45 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Emma Shelton ◽  
Edward L. Kuff ◽  
Elizabeth S. Maxwell ◽  
J. T. Harrington
Keyword(s):  
Electron Microscopy ◽  
Escherichia Coli ◽  
Plant Cells ◽  
Size And Shape ◽  
Two Peaks ◽  
Second Peak ◽  
Aminoacyl Transferase

It has been possible to show by electron microscopy of samples selected from sucrose gradients that particles of specific size and shape are present in supernatant fluids derived from nucleated animal and plant cells, but not in extracts from Escherichia coli. Aminoacyl transferase I activity in these same gradients sediments in two peaks representing material of approximately 5–7S and 18–20S. A rectangular particle, 100 x 145 A in size, sediments at 19S and coincides with the second peak of transferase I activity. The possibility that the rectangular particle may be a "carrier" particle associated with transferase I is discussed.

scholarly journals The magnitude of variation in temperature within a year has an effect on the seasonal variations of chickenpox incidence in Japan

2001 ◽  
Vol 126 (2) ◽  
pp. 269-277 ◽  
Author(s):  
A. KOKAZE ◽  
M. YOSHIDA ◽  
Y. SEKINE ◽  
M. ISHIKAWA ◽  
T. KUROKOCHI ◽  
...  
Keyword(s):  
Seasonal Variations ◽  
Close Correlation ◽  
Daily Temperature ◽  
Size And Shape ◽  
Different Types ◽  
Close Relationship ◽  
The Difference ◽  
Two Peaks ◽  
Second Peak

We investigated the epidemic pattern of chickenpox incidence among 47 prefectures in Japan. There were two peaks in chickenpox incidence in all prefectures. The first peaks appear at almost the same time in a year, while the second peaks occur at different times with relatively different types of size and shape. The feature of the second peak might characterize the epidemic pattern of chickenpox. We first introduced the second peak index, that is, the ratio of the difference between the incidence at the point of the second peak and the minimum incidence between the first and second peaks to the difference between the incidence at the point of the second peak and the minimum incidence in the year. There was a close correlation between the second peak index and the magnitude of variation in temperature within a year corresponding to the difference between the maximum and the minimum of the monthly mean of the highest daily temperature. This is the first article focusing on the close relationship between the second peak of epidemic pattern of chickenpox incidence and the variation of temperature within a year.

Characterisation of the Precipitates in Aged Al-4.2Cu-1.5Mg Alloy

2013 ◽  
Vol 774-776 ◽  
pp. 621-624
Author(s):  
Li Wei Quan ◽  
Chuan Cai Wang ◽  
Ying Ling Wang
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Vickers Hardness ◽  
Aged Alloy ◽  
Transmission Electron ◽  
Two Peaks ◽  
Second Peak

In this paper it is investigated the ageing dynamics of Al-4.2Cu-1.5Mg alloy aged at 170°C for different time. Vickers hardness and transmission electron microscopy were employed to test the hardness and microstructures of the aged alloy. It was found that there are two peaks in the curve. The first peak is attributed to the cluster hardening and the second peak is ascribed to the contribution of GPB zones.

Structural organization of escherichia coli ribosomes as determined by immuno electron microscopy

1978 ◽  
Vol 36 (2) ◽  
pp. 166-167 ◽  
Author(s):  
G. Stöffler ◽  
R.W. Bald ◽  
J. Dieckhoff ◽  
H. Eckhard ◽  
R. Lührmann ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Escherichia Coli ◽  
Ribosomal Proteins ◽  
Structural Organization ◽  
Three Dimensional ◽  
Ribosomal Subunit ◽  
Spatial Arrangement ◽  
Small Subunit ◽  
Antibody Binding ◽  
Immuno Electron Microscopy

A central step towards an understanding of the structure and function of the Escherichia coli ribosome, a large multicomponent assembly, is the elucidation of the spatial arrangement of its 54 proteins and its three rRNA molecules. The structural organization of ribosomal components has been investigated by a number of experimental approaches. Specific antibodies directed against each of the 54 ribosomal proteins of Escherichia coli have been performed to examine antibody-subunit complexes by electron microscopy. The position of the bound antibody, specific for a particular protein, can be determined; it indicates the location of the corresponding protein on the ribosomal surface.The three-dimensional distribution of each of the 21 small subunit proteins on the ribosomal surface has been determined by immuno electron microscopy: the 21 proteins have been found exposed with altogether 43 antibody binding sites. Each one of 12 proteins showed antibody binding at remote positions on the subunit surface, indicating highly extended conformations of the proteins concerned within the 30S ribosomal subunit; the remaining proteins are, however, not necessarily globular in shape (Fig. 1).

Scanning electron microscopy of plant cells using a variable-pressure SEM and cryogenic techniques

1993 ◽  
Vol 51 ◽  
pp. 260-261
Author(s):  
M. Yamada ◽  
K. Ueda ◽  
K. Kuboki ◽  
H. Matsushima ◽  
S. Joens
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Saturated Vapor ◽  
Plant Cells ◽  
Variable Pressure ◽  
Specimen Preparation ◽  
Operating Pressure ◽  
Vapor Pressures ◽  
Low Temperature Microscopy ◽  
Scanning Electron

Use of variable Pressure SEMs is spreading among electron microscopists The variable Pressure SEM does not necessarily require specimen Preparation such as fixation, dehydration, coating, etc which have been required for conventional scanning electron microscopy. The variable Pressure SEM allows operating Pressure of 1˜270 Pa in specimen chamber It does not allow microscopy of water-containing specimens under a saturated vapor Pressure of water. Therefore, it may cause shrink or deformation of water-containing soft specimens such as plant cells due to evaporation of water. A solution to this Problem is to lower the specimen temperature and maintain saturated vapor Pressures of water at low as shown in Fig. 1 On this technique, there is a Published report of experiment to have sufficient signal to noise ratio for scondary electron imaging at a relatively long working distance using an environmental SEM. We report here a new low temperature microscopy of soft Plant cells using a variable Pressure SEM (Hitachi S-225ON).

scholarly journals The study of multipeaked type-I X-ray bursts in the neutron star low-mass X-ray binary 4U 1636 − 536 with RXTE

2020 ◽  
Vol 501 (1) ◽  
pp. 168-178
Author(s):  
Chen Li ◽  
Guobao Zhang ◽  
Mariano Méndez ◽  
Jiancheng Wang ◽  
Ming Lyu
Keyword(s):  
Neutron Star ◽  
Flux Ratio ◽  
Light Curves ◽  
Type I ◽  
X Ray ◽  
Soft State ◽  
Peak Flux ◽  
Low Mass ◽  
Two Peaks ◽  
Second Peak

ABSTRACT We have found and analysed 16 multipeaked type-I bursts from the neutron-star low-mass X-ray binary 4U 1636 − 53 with the Rossi X-ray Timing Explorer (RXTE). One of the bursts is a rare quadruple-peaked burst that was not previously reported. All 16 bursts show a multipeaked structure not only in the X-ray light curves but also in the bolometric light curves. Most of the multipeaked bursts appear in observations during the transition from the hard to the soft state in the colour–colour diagram. We find an anticorrelation between the second peak flux and the separation time between two peaks. We also find that in the double-peaked bursts the peak-flux ratio and the temperature of the thermal component in the pre-burst spectra are correlated. This indicates that the double-peaked structure in the light curve of the bursts may be affected by enhanced accretion rate in the disc, or increased temperature of the neutron star.

Escherichia coli 70 S ribosome at 15 Å resolution by cryo-electron microscopy: localization of fmet-tRNAfMet and fitting of L1 protein

1998 ◽  
Vol 280 (1) ◽  
pp. 103-116 ◽  
Author(s):  
Arun Malhotra ◽  
Pawel Penczek ◽  
Rajendra K Agrawal ◽  
Irene S Gabashvili ◽  
Robert A Grassucci ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Escherichia Coli ◽  
Cryo Electron Microscopy ◽  
L1 Protein
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