scholarly journals VII. The monotreme skull: A contribution to mammalian morphogenesis

1916 ◽  
Vol 207 (335-347) ◽  
pp. 311-374 ◽  
Keyword(s):  
Close Approach ◽  
Text Book ◽  
Independent Investigation ◽  
Philosophical Methods ◽  
General Work

From the time, now nearly a century ago, when de Blainville, applying the philosophical methods he had developed for the classification of mammals to the knowledge of the structure of Echidna and Ornithorhynchus which had been obtained by Lamarck, Geoffroy St. Hilaire, and G. Cuvier, suggested that these two animals should perhaps form a group of the same order as the Marsupials and “Monodelphes,” many authors have studied their structure and discussed their affinities. Nearly all the great anatomists of the last century have at one time or another described the skull of a monotreme, either formally or in some text-book or other general work. Owing to the extreme difficulty of obtaining skulls which show sutures, their accounts vary to a very great extent. Finally, in 1901, Prof, van Bemmelen published a lengthy and magnificently illustrated account of the skulls of both monotremes which had every appearance of being a definitive description. Some years ago, when describing the skull of the “Cynodont” Diademodon, I endeavoured to institute a comparison between that animal, which in all ways makes an extremely close approach to mammalian structure, and the monotremes, admittedly the most reptilian of all mammals. To my very great surprise I found it impossible to compare the skull of Ornithorhynchus as interpreted by van Bemmelen with Diademodon. As at that time I had not sufficient material satisfactorily to undertake an independent investigation of the monotreme skull, I compared Diademodon with Dasyurus, a comparison which involves no difficulty.

scholarly journals Review of the Dynamical Aspects of Triple Systems

1977 ◽  
Vol 33 ◽  
pp. 145-150
Author(s):  
V. Szebehely
Keyword(s):  
Fundamental Problem ◽  
Stellar Dynamics ◽  
Close Approach ◽  
Type Systems ◽  
Computational Results ◽  
Transient Phenomena ◽  
Triple Systems ◽  
Families Of Periodic Orbits ◽  
Negative Total Energy

AbstractA classification of possible motions of triple systems is presented emphasizing the transient phenomena occurring in addition to the final (asymptotic) outcome and clarifying the discrepancies between the astronomical and mathematical formulations. A conjectured possible instability is described and it is shown that systems with negative total energy and low angular momentum may lead to instability and to the formation of binaries. The ejected or escaping star may have high velocity if the triple close approach preceding the escape is sufficiently close. The computational results of several systematic series of such escapes are applied to various stellar configurations.The present status of the fundamental problem of partitioning the phase-space into stable and unstable regions is reviewed and a recently developed technique, applicable to stellar dynamics is described. Recently discovered families of periodic orbits and previously established classical configurations are shown to weaken the general instability conjecture.The possible existence of triple systems in states of dissolution offer intriguing observational challenges regarding the discovery of these projected temporary trapezium type systems.

Classification of Swing-By Trajectories Using the Moon

1995 ◽  
Vol 48 (11S) ◽  
pp. S138-S142 ◽  
Author(s):  
Antonio Fernando Bertachini de Almeida Prado ◽  
Roger Broucke
Keyword(s):  
Large Range ◽  
Initial Conditions ◽  
Close Approach ◽  
The Body ◽  
The Moon ◽  
Three Body Problem ◽  
Jacobian Constant ◽  
Three Body ◽  
The Mathematical Model

In the present paper we study and classify the swing-by maneuvers that use the Moon as the body for the close approach. The goal is to simulate a large variety of initial conditions for those orbits and classify them according to the effects caused by the close approach in the orbit of the spacecraft. Special attention is given to identify the regions where the captures and escapes occur. The classical three parameters (Jacobian constant, pericenter distance and angle of approach) used to identify a Swing-By maneuver are varied in large intervals to cover a large range of possibilities for the maneuver. Letter-plots figures are made to show the results obtained in a compact form. The theoretical prediction that for 0° ≤ ψ ≤ 180° the spacecraft losses energy and for 180° ≤ ψ ≤ 360° the spacecraft gains energy is confirmed. Regions containing trajectories that are candidates to generate Belbruno-Miller trajectories are identified. The well-known planar restricted circular three-body problem is used as the mathematical model. The equations are regularized (using Lamaiˆtre’s regularization), so it is possible to avoid the numerical problems that come from the close approach with the Moon.

Some Footnotes to Salmond's Jurisprudence

1941 ◽  
Vol 7 (2) ◽  
pp. 206-223 ◽  
Author(s):  
A. H. Campbell
Keyword(s):  
Text Book ◽  
Teachers And Students ◽  
Ninth Edition ◽  
The Subject

The following notes are offered in the hope that they may be of some use to teachers and students who are using (as the writer has for some years used) Salmond's Jurisprudence as a text-book for the subject of the Nature and Classification of Rights. They do not pretend to be systematic, and they are meant to be supplementary to the excellent and informative notes of Mr. J. L. Parker to the ninth edition. The page references are to the ninth edition; the section references (§§) will serve for earlier editions as well.

Blood and urine chlorides in rheumatic infection

1934 ◽  
Vol 30 (7-8) ◽  
pp. 674-678
Author(s):  
M. I. Krymsky ◽  
I. B. Shulutko
Keyword(s):  
Rheumatic Diseases ◽  
Present Report ◽  
Biochemical Properties ◽  
The Body ◽  
Research Attention ◽  
Clinical Characteristic ◽  
General Work

The study of rheumatic diseases has attracted exceptional research attention in recent years. Along with the precise detailing of the classification of rheumatic diseases of the joints, the clinical characteristic of rheumatic diseases is revisited and clarified. Recently, the biochemical properties of the body and the entire course of metabolism in rheumatic infection have also been subjected to detailed study. In the present report, which is part of the general work carried out in our clinic to study rheumatism, we present data characterizing variations in chloride in the blood and urine in rheumatic diseases.

scholarly journals GROUP COHESION AS A FACTOR OF SOCIAL IDENTIFICATION

2020 ◽  
Vol 65 (4) ◽  
pp. 214-218
Author(s):  
B.D. Zhigitbekova ◽  
◽  
M. Serikbay ◽  
Keyword(s):  
Social Problems ◽  
Group Cohesion ◽  
Social Identification ◽  
Group Training ◽  
Training Methods ◽  
Psychological Practice ◽  
Psychological Training ◽  
Change Of Life ◽  
General Work

Resumes In the article come into question basic methods of the psychological training. Concrete mechanisms and features of the use of psychotherapy methods come into question. Positive approaches, sent to the change of life of client, the processes sent tothe aims are examined. In works И. В. Вачкова will in detail come into question problems of methods of the group training and all-round analysis. At the discussion of problem of psychological practice specialists mark that not a single psychological method can work out social problems. In particular, two types of objects are individual and group. Then he analyses possibility of classification of training methods as oriented to the separate participants and oriented to general work.

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