scholarly journals The projection of the forebrain on the pons and cerebellum

1934 ◽  
Vol 115 (795) ◽  
pp. 504-522 ◽  
Keyword(s):  
Human Brain ◽  
Experimental Work ◽  
The Other ◽  
Comparative Neurology ◽  
Animal Kingdom ◽  
Complete Answer ◽  
Logical Conclusion ◽  
Continuous Narrative

Although the existence of the cortico-pontine fibres has long been recognized and their functions partially elucidated in more recent times, there has as yet been no solution of the problem of their distribution in the pons and projection on the cerebellum. The thorough investigation of the problem requires prolonged and tedious experimental work and has, probably on that account, hitherto been largely neglected. But experiments are not performed only by man. In obscure recesses of the animal kingdom lie hidden experiments of Nature which, confined within the limits of the direction of evolution chosen for them, have been condemned to carry their eccentricity to its logical conclusion. Experiments of an even more casual nature have been performed by the indiscriminate invasion of every part of the human brain by pathological processes; but it is only by the patient collection and examination of vast masses of records that any continuous narrative can be extracted from the chaotic whole. Of the three types of experiment available it is more economical of time and material to chose that which comes ready-made: the method of comparative neurology. This, even if it does not supply a complete answer, at least provides valuable clues for the more accurate direction of the other methods.

XXVII.—The Inheritance of Long and Short Wings in the Weevil, Sitona hispidula, with a Discussion of Wing Reduction among Beetles

1928 ◽  
Vol 55 (3) ◽  
pp. 665-735 ◽  
Author(s):  
Dorothy J. Jackson
Keyword(s):  
Experimental Work ◽  
Adult Stage ◽  
Point Of View ◽  
The Other ◽  
Wing Dimorphism ◽  
Wing Reduction ◽  
Hereditary Factors ◽  
The Subject ◽  
The One ◽  
Evolutionary Point

It is well known that in many orders of typically winged insects species occur which in the adult stage are apterous or have the wings so reduced in size that flight is impossible. Sometimes the reduction of wings affects one sex only, as in the case of the females of certain moths, but in the majority of cases it is exhibited by both sexes. In many instances wing dimorphism occurs irrespective of sex, one form of the species having fully developed wings and the other greatly reduced wings. In some species the wings are polymorphic. The problem of the origin of reduced wings and of other functionless organs is one of great interest from the evolutionary point of view. Various theories have been advanced in explanation, but in the majority of cases the various aspects of the subject are too little known to warrant discussion. More experimental work is required to show how far environmental conditions on the one hand, and hereditary factors on the other, are responsible for this phenomenon. Those species which exhibit alary dimorphism afford material for the study of the inheritance of the two types of wings, but only in a few cases has this method of research been utilized.

Organisms With Nervous Systems

2019 ◽  
pp. 23-34
Author(s):  
Dale Purves
Keyword(s):  
Nervous System ◽  
Operating Principle ◽  
The Other ◽  
Neural Systems ◽  
Animal Kingdom ◽  
Nervous Systems ◽  
Life On Earth

Definitions of the term “animals” in dictionaries and textbooks are surprisingly vague. The characteristics usually mentioned are eukaryotic, multicellular, heterotrophic, sexually reproducing, and capable of rapid and independent movement. But some or all of these properties are characteristic of many organisms in the other kingdoms of life on Earth. In fact, the major distinguishing feature of animals in most cases is the presence of a nervous system. But if nervous systems are indeed one of the main attributes that distinguish organisms in the animal kingdom, what exactly are nervous systems and what advantages do they bring? Without at least some provisional answers, seeking the operating principle of neural systems would be futile.

“ Ten Years' Testing of Model Seaplanes ”

1923 ◽  
Vol 27 (149) ◽  
pp. 224-243
Author(s):  
G. S. Baker
Keyword(s):  
Experimental Work ◽  
Royal Society ◽  
General Meeting ◽  
National Physical Laboratory ◽  
The Other ◽  
Experimental Tank ◽  
Know How ◽  
Other Hand ◽  
Physical Laboratory ◽  
Hull Design

An Ordinary General Meeting- of the Society was held at the Royal Society of Arts, on Thursday, February ist, 1923, Professor L. Bairstow in the chair.The Chairman, in opening- the proceedings, said that Mr. G. S. Baker, O.B.E., of the National Physical Laboratory, would deal with flying boats and seaplanes. He would deal with the hull and its design, that part of the seaplane which differentiates it from the aeroplane. That subject had been touched on very lightly by Major Rennie at the previous meeting of the Society, in view of the present paper by Mr. Baker.Mr. Baker had begun work in 1912 on the problems of hull design, at a time when nothing of a definite nature was known; a few individual experiments had been carried out, but there was no systematised knowledge at all at that time. From that state of ignorance a great deal of experimental work had now rescued us. He did not know how far Mr. Baker would stress the point, but it was quite clear, from the investigation of certain accidents to seacraft, that there were fundamental differences in the behaviour of seaplane hulls on the water, differences which had a great deal of effect on the risk of flying-. For instance, if one type of hull was such that when the plane rose in the air it stalled, then all the aerodynamical consequences of stalling- followed, and there was difficulty. On the other hand, it appeared that we had a type of flying- boat which did not make the plane stall on getting into the air, and consequently if it came back to the water it was still controlled. For this type of development, which he believed really dated back to the C.E.i, we were mainly indebted to Mr. Baker and his associates at the National Physical Laboratory, and to the generosity of Sir Alfred Yarrow in placing such a magnificent piece of apparatus as the experimental tank at the disposal of the nation.Mr. Baker then read his paper on “ Ten Years’ Testing of Model Seaplanes.”

scholarly journals Newton as an experimenter

1943 ◽  
Vol 181 (986) ◽  
pp. 244-250
Keyword(s):  
Experimental Work ◽  
Furnace Operation ◽  
The Other ◽  
Theoretical Studies ◽  
Other Hand ◽  
Made In ◽  
Grinding And Polishing ◽  
At Home

The duty has been assigned to me of telling you something about Newton as an experimentalist. As the result of a study of what is known of his history, it seems to me that among his various intellectual pursuits experiment was his first love and the love to which he was most constant. Strange though it be, he seems in some moods to have doubted whether his theoretical studies were worth while, and I do not recall any case where he expressed himself enthusiastically about them. On the other hand, he speaks of his optical work as ‘The oddest if not the most considerable detection which has hitherto been made in the operation of nature.’ Newton loved the mechanical side of experimental work. As a boy he constructed sundials, and, what is more, fixed one of them into the side of the house effectually enough for it to be there a century later. A notebook of his boyhood shows him assiduous in collecting recipes for various kinds of drawing materials, and he notes methods of performing some (rather nasty) conjuring tricks. Later on, when he is making his reflecting telescope, it is obvious that he is a skilled amateur mechanic, at home in furnace operation. He builds his own brick furnace, prepares speculum metal, and is apparently more successful than the professional opticians of the time in grinding and polishing it to a satisfactory spherical figure. (The days of parabolizing were not yet.) It was not until a good many years later that they were able to put such instruments on the market.

scholarly journals Supersonic dispersion in gases

1934 ◽  
Vol 146 (856) ◽  
pp. 56-71 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Experimental Work ◽  
High Frequency ◽  
Response Curve ◽  
Wave Length ◽  
Soap Film ◽  
The Other ◽  
Rapid Degradation ◽  
Compressional Waves ◽  
Point Electrode

The rapid degradation of intensity suffered by compressional waves of high frequency in gases was first observed by pierce in carbon dioxide for frequencies in the neighbourhood of 2.10 5 cycles/sec. Although in the last few years a considerable number of measurements of the velocity of supersonic waves have been made, less experimental work has been done on the absorption . This present paper describes some work aimed at elucidating the mechanism of the phenomenon. Consideration was first given to the establishment of a source of vibrations of the requisite frequency. The possible apparatus reduces itself to four types: (1) edge-tones, (2) electric sparks, (3) small resonators of gas, (4) solid resonators; both of the latter types to be maintained by oscillating circuits incorporating valves. The frequency of an edge-tone depends directly on the velocity of the blast, and inversely on the distance from the blower to the edge, so that it should be possible to produce supersonic waves by making the former very large and the latter very small; in fact, Hartmann has already used such a source. The difficulty of maintaining constant blast velocity and the complications which the blast introduces in the propagation of such waves would, however, have made such a source unmanageable in the present work. Nekle-pajev has used sparks as sources in the examination of the absorption in air. But here again the frequency is difficult to measure or to maintain constant. Some success was obtained by the author with gaseous resonators consisting of short brass tubes terminated at one end by a brass stopper, and at the other end by a soap film, the distance between the two being half the wave-length at the frequency of excitation. The resonator was maintained in vibration by a valve oscillator, of which the plate was connected to a point electrode just above the soap film, while the grid was connected to the brass tube itself. Response of the resonator due to electrostatic attraction of the film was observed by the image of a glowing filament reflected from the slightly concave film on to a scale. By varying the tuning of the oscillator the response curve of the little resonator could be obtained.

Anaerobic-Aerobic Treatment of Industrial Wastewater

1988 ◽  
Vol 20 (4-5) ◽  
pp. 189-198 ◽  
Author(s):  
H. Bode
Keyword(s):  
Experimental Work ◽  
Industrial Wastewater ◽  
Sugar Industry ◽  
Anaerobic Treatment ◽  
Full Scale ◽  
The Other ◽  
Aerobic Treatment ◽  
Industrial Wastewaters ◽  
Pulp Industry ◽  
Aerobic Process

The paper evaluates the question of whether a combined anaerobic-aerobic or a solely aerobic treatment of some particular industrial wastewaters leads to better results. Therefore three different industrial wastewaters were treated in two different process lines: one line consisted of anaerobic treatment prior to aerobic treatment and in the other, only aerobic treatment was applied. The experiments were run with wastewater from:–the pectin industry–the sugar industry (beet sugar)–the animal pulp industry. The data presented in this paper were gained from experimental work which was conducted over a period of two years. Different scales of treatment plants were used. The anaerobic treatment was done in full- and semitechnical scale reactors, while the aerobic treatment took place in labscale and semitechnical scale plants. Surprisingly in all three cases the solely aerobic treatment led to slightly better results in terms of residual pollution. Finally the paper presents data gained from a recently built, full-scale anaerobic-aerobic process which treats pectin waste. The aerobic stage of the process was designed on the basis of the results from the experimental work which was mentioned above. The results from the former experimental work and from the full-scale operation are compared.

Control of Aeroplanes at Low Speeds

1923 ◽  
Vol 27 (154) ◽  
pp. 473-487
Keyword(s):  
Experimental Work ◽  
The Other ◽  
Research Committee ◽  
General Direction ◽  
Private Person ◽  
Other Hand ◽  
Low Speeds ◽  
Combined Work ◽  
The Way

I must begin by explaining how I come to be giving this lecture. The experimental work with which I shall deal has, for the most part, been done at the N.P.L. and the R.A.E., under the general direction of the Aeronautical Research Committee. The way in which I come to be connected with the work is that I am a member of this Committee and am Chairman of a small panel that was created, some three years ago, by the Committee, to deal with this and other work relating to control and stability. The experiments that I shall describe and the methods of dealing with the results that I shall employ are, therefore, the results of the combined work of a considerable number of people. I can thus claim no special ownership of any of the ideas that I shall use, except in so far as I belong to the panel that has been working upon them. On the other hand I am giving the lecture as a private person, so that any views I express are personal ones and in no sense official.

Q-Phenomena, I-Phenomena and Impliciture: Some Experimental Pragmatics

2009 ◽  
Vol 1 (1) ◽  
pp. 84-117 ◽  
Author(s):  
Robert Harnish ◽  
Merrill Garrett
Keyword(s):  
Frontal Lobe ◽  
Experimental Work ◽  
Background Knowledge ◽  
Generative Grammar ◽  
Linguistic Theory ◽  
The Other ◽  
Background Information ◽  
Experimental Pragmatics ◽  
Frontal Lobe Function ◽  
Initial Results

AbstractElements of communicative content that are not expressed by constituents of the sentence uttered, what we will call "unexpressed elements of content" (UECs), played an important role in the history and development of generative grammar. In the 80's and 90's, mostly inspired by the work of Grice, UECs and mechanisms for recovering them not contemplated by linguistic theory of the time, began to surface under a variety of labels. We will collectively refer to these phenomena as 'impliciture' (extending Bach: 1994). Impliciture phenomena raise some interesting questions, only some of which is the field in a position to say anything about at present. Levinson (2000) has taken the useful step of distinguishing what we call "Q-phenomena", mostly related to linguistic scales, from "I-phenomena", mostly related to stereotypical information. Starting in the late 80's, experimental work began on the nature of these unspoken contents and their attendant mechanisms. In a recent study, Garrett and Harnish (2007) looked at I-phenomena, that have been proposed to depend on stereotypical background information. We asked whether these contents really are delivered by such mechanisms as "default heuristics", operating on general background knowledge, or whether they might be more tied to language via something like the "standardization" of a form for a certain use. Initial results for the materials tested seem to favor standardization as a mechanism for delivering this content. Completed research by Orjada (2007) and Rybarova (2007) extends the study of impliciture to additional examples and new populations. One assesses performance in RH damaged populations. The other contrasts performance for populations with high and low frontal lobe function.

scholarly journals Factors affecting the breeding of the field mouse ( Microtus agrestis ). Part III.—Locality

1933 ◽  
Vol 113 (784) ◽  
pp. 486-495 ◽  
Keyword(s):  
Experimental Work ◽  
The Other ◽  
Microtus Agrestis ◽  
Field Mouse ◽  
Factors Affecting ◽  
Intermediate Area ◽  
Forestry Commission ◽  
North And South

The first two papers in this series (1932, a and b ) were descriptions of experimental work. This third paper is based upon observation. In order to study the effect of latitude upon the starting and stopping of breeding, we chose three areas in a nearly north and south line. The most northerly was about 360 miles from the most southerly, and the other area was roughly half way between them. All three areas were elevated grassland belonging to the Forestry Commission, whom we must thank for their kind co-operation, without which the investigation would have been impossible. The most northerly area was at Huntly in Aberdeenshire. The intermediate area was at Newcastleton in Roxburghshire. The most southerly area was at Corris in Merionethshire (see fig. 1.). The Aberdeen and Roxburgh areas were at elevations of about 700 feet, and the Merioneth area at between 500 and 600 feet. Microtus agrestis was caught in each area as nearly as possible every month from January, 1930, to December, 1931. Deep snow and other causes occasionally prevented the monthly trapping in one or other area. On the average 32 Microtus were caught each month during these tow years in Aberdeen, 29 in Roxburgh, and 43 in Merioneth. The total number of mice caught in all three areas was precisely 2500.

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