The present position and control of rice diseases in India

1959 ◽  
Vol 49 (5) ◽  
pp. 349-362
Author(s):  
S. Y. Padmanabhan
Keyword(s):  
Present Position ◽  
And Control

Third Report on a Test of Mcdougall'S Lamarckian Experiment on the Training of Rats

1948 ◽  
Vol 25 (2) ◽  
pp. 103-122
Author(s):  
W. E. AGAR ◽  
F. H. DRUMMOND ◽  
O. W. TIEGS
Keyword(s):  
Body Size ◽  
Genetic Differences ◽  
Colour Pattern ◽  
Control Line ◽  
Present Position ◽  
Progressive Decline ◽  
Lamarckian Inheritance ◽  
Successive Generations ◽  
And Control

This experiment, to test McDougall's conclusion that the effects of training are inherited, has now been carried on for thirty-six generations, involving the training of 2827 rats. The present position of the problem raised by McDougall may be summarized as follows: Neither our own experiment, nor that of Crew, shows any evidence of increasing facility in learning attributable to trained ancestry. McDougall's claim that the progressive decline in the number of errors which he found in successive generations of trained rats is an example of Lamarckian inheritance cannot be maintained in face of the facts (a) that he did not keep a control line, (b) that we have found a progressive decline in our trained line similar to McDougall's, but this was paralleled by the control line; moreover, after about twenty-eight generations, the number of errors progressively increased again in both lines. McDougall's further argument from the change from a zero-day preference for the bright gangway in earlier generations to a preference for the dim gangway in later generations is invalid; it is shown, from his own figures, to be capable of a different explanation. The discovery of genetic differences in colour pattern and body size between our trained and control lines, presumably due to mutations, emphasizes the difficulty of interpreting genetic differences in facility of learning, even if they should occur, as due to the Lamarckian factor. The experiment is being continued.

Ballistic Research Rockets With Particular Reference to Black Knight

1961 ◽  
Vol 65 (603) ◽  
pp. 171-189
Author(s):  
D.J. Lyons
Keyword(s):  
Wind Tunnel ◽  
Research And Development ◽  
Ballistic Missile ◽  
The Other ◽  
Present Position ◽  
Queen Mary College ◽  
Stability And Control ◽  
Aeronautical Engineering ◽  
And Control

The 1172nd Main Lecture to be given before the Society and the 41st to be held at a Branch centre “Ballistic Research Rockets with Particular Reference to Black Knight” was given under the auspices of the Luton Branch on 1st December 1960. Mr. F. H. Pollicutt, F.R.Ae.S., Chairman of the Luton Branch opened the meeting by welcoming the President, Dr. E. S. Moult, C.B.E., B.Sc., F.R.Ae.S., M.I.Mech.E., the other members of the Council of the Main Society who were present, and representatives from the Bristol, Birmingham and Wolverhampton, Coventry, Christchurch, Derby, Hatfield, Halton, Henlow, Preston and Weybridge Branches. He then asked Dr. Moult to preside over the rest of the proceedings.Dr. Moult expressed his pleasure at being present on this occasion–the second time a Main Society Lecture had been presented at the Luton Branch–and then introduced the Lecturer, Mr. D. J. Lyons. Mr. Lyons took his degree in Aeronautical Engineering at Queen Mary College and subsequently joined the Wind Tunnel staff at Farnborough. During the war he became a flying instructor in the R.A.F. and later rejoined the Aerodynamics Flight Section at. the R.A.E. For the next ten years Mr. Lyons was engaged in Flight Research on stability and control. In 1951 he was appointed Superintendent of the Experimental Projects Division in the Guided Weapons Department and in 1955 was promoted to his present position as Senior Superintendent of the Ballistic Missile Group of the Guided Weapons Department. He had been responsible from the Ministry aspect for the research and development connected with the Black Knight and Blue Streak Missile systems.

A Discussion on recent advances in heavy electrical plant - Future developments in the control of power systems

1973 ◽  
Vol 275 (1248) ◽  
pp. 243-253
Keyword(s):  
Power Systems ◽  
Minimum Cost ◽  
Constant Voltage ◽  
Present Position ◽  
Future Developments ◽  
Operational Characteristics ◽  
On Line ◽  
Computer Based ◽  
The Cost ◽  
And Control

The basic requirement of the control system is to ensure the supply of electric power at constant voltage and frequency exactly in accordance with the instantaneous demand. Its design is dominated by ( a ) the characteristics of the consumers’ demand; ( b ) the provision of a reliable supply, even under fault conditions, at minimum cost; ( c ) the technical and operational characteristics of a mixture of fossil-fired, nuclear and hydro generators; ( d )an assessment of the benefits to be gained and the cost of implementation. Large modern generating units are complex and their characteristics and those of the transmission system are such as to increase the difficulties of operation and control beyond the unaided capabilities of hum an operators. Automatic aids, many of them computer-based, are being used increasingly. The paper reviews the present position and indicates how advances in control technology could lead to on-line control of the system at acceptable cost.

Control of Metal Alloy Oxidation with Electric Fields

1973 ◽  
Vol 31 ◽  
pp. 164-165
Author(s):  
R. R. Dils ◽  
P. S. Follansbee
Keyword(s):  
Electric Fields ◽  
Oxidation Process ◽  
Base Alloy ◽  
Oxide Surface ◽  
Platinum Electrodes ◽  
Insulating Layer ◽  
Iron Base Alloy ◽  
Alloy Oxidation ◽  
Aluminum Oxide Layer ◽  
And Control

Electric fields have been applied across oxides growing on a high temperature alloy and control of the oxidation of the material has been demonstrated. At present, three-fold increases in the oxidation rate have been measured in accelerating fields and the oxidation process has been completely stopped in a retarding field.The experiments have been conducted with an iron-base alloy, Pe 25Cr 5A1 0.1Y, although, in principle, any alloy capable of forming an adherent aluminum oxide layer during oxidation can be used. A specimen is polished and oxidized to produce a thin, uniform insulating layer on one surface. Three platinum electrodes are sputtered on the oxide surface and the specimen is reoxidized.

Evidence for a Blood Ganglion Barrier in the Superior Cervical Ganglion of the Rat

1982 ◽  
Vol 40 ◽  
pp. 204-204
Author(s):  
D. M. DePace
Keyword(s):  
Blood Vessels ◽  
Superior Cervical Ganglion ◽  
Peripheral Nerves ◽  
Time Schedule ◽  
Transmission Electron ◽  
Cervical Ganglion ◽  
The Central Nervous System ◽  
Cervical Ganglia ◽  
Capillary Circulation ◽  
And Control

The majority of blood vessels in the superior cervical ganglion possess a continuous endothelium with tight junctions. These same features have been associated with the blood brain barrier of the central nervous system and peripheral nerves. These vessels may perform a barrier function between the capillary circulation and the superior cervical ganglion. The permeability of the blood vessels in the superior cervical ganglion of the rat was tested by intravenous injection of horseradish peroxidase (HRP). Three experimental groups of four animals each were given intravenous HRP (Sigma Type II) in a dosage of.08 to.15 mg/gm body weight in.5 ml of.85% saline. The animals were sacrificed at five, ten or 15 minutes following administration of the tracer. Superior cervical ganglia were quickly removed and fixed by immersion in 2.5% glutaraldehyde in Sorenson's.1M phosphate buffer, pH 7.4. Three control animals received,5ml of saline without HRP. These were sacrificed on the same time schedule. Tissues from experimental and control animals were reacted for peroxidase activity and then processed for routine transmission electron microscopy.

Effects of renovascular hypertension on rat adrenal zona glomerulosa

1978 ◽  
Vol 36 (2) ◽  
pp. 582-583
Author(s):  
G. Mazzocchi ◽  
P. Rebuffat ◽  
C. Robba ◽  
P. Vassanelli ◽  
G. G. Nussdorfer
Keyword(s):  
Renovascular Hypertension ◽  
Left Kidney ◽  
Renin Angiotensin System ◽  
Plasma Renin ◽  
Zona Glomerulosa ◽  
Ultrastructural Changes ◽  
Albino Rats ◽  
Left Renal Artery ◽  
Angiotensin System ◽  
And Control

It is well known that the rat adrenal zona glomerulosa steroidogenic activity is controlled by the renin-angiotensin system. The ultrastructural changes in the rat zona glomerulosa cells induced by renovascular hypertension were described previously, but as far as we are aware no correlated biochemical and morphometric investigations were performed.Twenty adult male albino rats were divided into 2 experimental groups. One group was subjected to restriction of blood flow to the left kidney by the application of a silver clip about the left renal artery. The other group was sham-operated and served as a control. Renovascular hypertension developed in about 10 days: sistolic blood pressure averaged 165 ± 6. 4 mmHg, whereas it was about 110 ± 3. 8 mmHg in the control animals. The hypertensive and control rats were sacrificed 20 days after the operation. The blood was collected and plasma renin activity was determined by radioimmunological methods. The aldosterone concentration was radioimmunologically assayed both in the plasma and in the homogenate of the left capsular adrenal gland.

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