scholarly journals The external mechanics of the chromosomes I—The scope of enquiry

1936 ◽  
Vol 121 (823) ◽  
pp. 264-273 ◽  
Keyword(s):  
Experimental Tests ◽  
Internal Factors ◽  
Clear Cut ◽  
Essential Properties ◽  
Most Significant Change ◽  
Systematic Group ◽  
The One ◽  
External Stimuli ◽  
Chromosome Movements ◽  
Permanent Structure

The movement of chromosomes may be regarded in two kinds of relationships according as it involves changes of shape and changes of position. The first are due to movements within the chromosomes, and may be used to infer their internal mechanics . The second are due to movements between chromosomes, and may be used to infer their external mechanic . Many experiments have been devoted to elucidating the principles of the external mechanics, and they have been successful in showing certain essential properties of the cell outside the nucleus, particularly of the spindle and the spindle-determining bodies or centrosomes. But, when applied to the chromosomes, artificial treatment has the drawback that in making one primary change it sets up a series of secondary changes whose importance cannot be accurately assessed; comparison is therefore vitiated. The cytoplasm and, in the resting nucleus, a semi-permeable nuclear membrane separates and protects the chromosomes from external stimuli. Thus micro-dissection and etherization have clear-cut effects on chromosome movements, but these may be secondary consequences of an action upon the cytoplasm. The value of experimental tests being thus limited, we are thrown back on the comparison of the behaviour of chromosomes in different natural circumstances. The number of variables is then under genetical control and the method of inference depends on genetical assumptions. But the necessary assumptions are now fairly well defined. We take it that the behaviour of the chromosomes depends on three variable factors: genotype, environment, and permanent structure, and there are usually means by which we can eliminate differences due to two of these. The characteristic differences between different species and varieties, for example, are due to differences of genotype, and they fall for the most part within a narrow range, the narrower the smaller the systematic group concerned. Even the most significant change that has arisen in the evolution of the genetic mechanism, the change from mitosis to meiosis, can be represented as the consequence of a shift in the time-coordination between external and internal factors in the development of the chromosomes, a precocity of the one relative to the other.

scholarly journals From reflex to reflection: Moving from the space of causes to the space of reasons and back

2020 ◽  
Vol 3 (1) ◽  
pp. 681-693
Author(s):  
Ariel Furstenberg
Keyword(s):  
The Other ◽  
Final Part ◽  
Clear Cut ◽  
Other Hand ◽  
Space Of Reasons ◽  
The One ◽  
The Relationship ◽  
Simple Picture

AbstractThis article proposes to narrow the gap between the space of reasons and the space of causes. By articulating the standard phenomenology of reasons and causes, we investigate the cases in which the clear-cut divide between reasons and causes starts to break down. Thus, substituting the simple picture of the relationship between the space of reasons and the space of causes with an inverted and complex one, in which reasons can have a causal-like phenomenology and causes can have a reason-like phenomenology. This is attained by focusing on “swift reasoned actions” on the one hand, and on “causal noisy brain mechanisms” on the other hand. In the final part of the article, I show how an analogous move, that of narrowing the gap between one’s normative framework and the space of reasons, can be seen as an extension of narrowing the gap between the space of causes and the space of reasons.

scholarly journals Exploring International and Inter-Sector Differences of Social Enterprises in the UK and India

2021 ◽  
Vol 13 (11) ◽  
pp. 5870
Author(s):  
Philipp Kruse
Keyword(s):  
Social Entrepreneurship ◽  
Social Enterprise ◽  
Social Enterprises ◽  
Future Research ◽  
Shape Features ◽  
Qualitative And Quantitative ◽  
Clear Cut ◽  
The One ◽  
Definition Of ◽  
The Uk

Social Entrepreneurship (SE) describes a new entrepreneurial form combining the generation of financial and social value. In recent years, research interest in SE increased in various disciplines with a particular focus on the characteristics of social enterprises. Whereas a clear-cut definition of SE is yet to be found, there is evidence that culture and economy affect and shape features of SE activity. In addition, sector-dependent differences are supposed. Building on Institutional Theory and employing a mixed qualitative and quantitative approach, this study sheds light on the existence of international and inter-sector differences by examining 161 UK and Indian social enterprises. A content analysis and analyses of variance were employed and yielded similarities as well as several significant differences on an international and inter-sector level, e.g., regarding innovativeness and the generation of revenue. The current study contributes to a more nuanced picture of the SE landscape by comparing social enterprise characteristics in a developed and a developing country on the one hand and different sectors on the other hand. Furthermore, I highlight the benefits of jointly applying qualitative and quantitative methodologies. Future research should pay more attention to the innate heterogeneity among social enterprises and further consolidate and extend these findings.

scholarly journals Introducing Basic Concepts: In Search of the Missing Scaffolds

2017 ◽  
Vol 13 (4) ◽  
pp. 4-14 ◽  
Author(s):  
G.A. Zuckerman ◽  
O.L. Obukhova ◽  
L.A. Ryabinina ◽  
N.A. Shibanova
Keyword(s):  
Fairy Tale ◽  
First Graders ◽  
Educational Games ◽  
Young Student ◽  
Educational Models ◽  
Motivational Support ◽  
Essential Properties ◽  
The Subject ◽  
The One ◽  
Grade One

What are the conditions for the intersection and mutual enrichment of two separate lines of development of conceptual thinking – those of everyday and scientific notions? We assume that such intersection would require at least two conditions. The first one is well known: it is modeling of essential properties of the subject under study. Educational models are providing hand-on actions of the young student with a theoretical content of the notion. The second condition is the motivational support for constructing educational models. This condition is not fulfilled as evidenced by the lack of students’ initiative in creating and using the educational models at the early stages of the introduction of scientific concepts. We expected the conceptual characters of educational games to complement scaffolding for bringing the initial concepts into the systematic school curricula?. On the one hand, these conceptual characters act according to the logic of the concept, on the other hand, they exist as the fairy-tale heroes. Our hypothesis is supported by the evidence from the formative experiments in grade one. When the conceptual characters became part of the lessons, learning became impregnated with feelings, imagination and initiative; in particular, the first-graders were building the learning models without any suggestions from their teacher. The assessment of these students showed that the introduction of the initial concepts with the help of conceptual characters significantly affected the very concepts thus developed; in particular, it promoted their attribution to the essential properties of the subject under study.

Early Bantu Ethnography from a Philological Point of View

Africa ◽  
1930 ◽  
Vol 3 (1) ◽  
pp. 31-48 ◽  
Author(s):  
N. J. v. Warmelo
Keyword(s):  
Point Of View ◽  
The Other ◽  
Bantu Languages ◽  
Clear Cut ◽  
Other Hand ◽  
Compact Body ◽  
The One ◽  
Opening Paragraph

Opening ParagraphFew of the secrets that Africa still holds from us to-day have, I think, such an absorbing interest as the problem of Bantu in its relation to the neighbouring families and types of speech. Taking the continent of Africa as a whole, we find on the one hand the huge, yet marvellously homogeneous and compact body of the Bantu languages, clear-cut in structure, simple and transparent in phonology, and, at the back of much apparent diversity, exceptionally uniform in vocabulary. On the other hand there are in Africa numerous other languages of various type, which differ so much amongst each other that they have not yet been brought under any but the very broadest of classifications. The essential points of these are as follows.

Time-dependent Changes in Prostaglandin Excretion in Response to Frusemide in Man

1979 ◽  
Vol 56 (1) ◽  
pp. 77-81 ◽  
Author(s):  
B. Scherer ◽  
P. C. Weber
Keyword(s):  
Haemodynamic Effects ◽  
Invasive Technique ◽  
Urinary Volume ◽  
Clear Cut ◽  
Non Invasive ◽  
Urinary Potassium ◽  
The One ◽  
Vascular Compartment ◽  
Stimulation Of

1. To evaluate in man by a non-invasive technique the possible role of prostaglandin (PG) compounds in initial renal haemodynamic effects after frusemide we studied the urinary excretion of PGE2 and of PGF2α before and at 15 min and 120 min after intravenous injection of this drug. 2. An increase of PGE2 and of PGF2α excretion was found in all 19 volunteer subjects within 15 min after frusemide, and PG excretion had returned towards control values at 120 min. The stimulation of PGF2α excretion by frusemide was markedly lower in men than in women, but this difference was statistically not significant. 3. No clear-cut relation was found between urinary PG compounds, on the one hand, and urinary volume, urinary sodium and urinary potassium, on the other hand, during the study. 4. The results support the assumption that the rapid increase of urinary PG compounds after frusemide, which parallels the changes in renal haemodynamics, may be an indicator of an activation of the PG system, in part or predominantly, in the vascular compartment.

SPECIAL REVIEWS

PEDIATRICS ◽  
1951 ◽  
Vol 7 (2) ◽  
pp. 269-293
Author(s):  
CHARLES C. CHAPPLE
Keyword(s):  
The Body ◽  
Caloric Content ◽  
Maturation Factor ◽  
Drug Actions ◽  
The Common ◽  
Cellular Permeability ◽  
The One ◽  
External Stimuli ◽  
The Brain

A study has been made of the known phenomena which affect the biologic organism. Certain correlations have been found and other correlations are logically inferred. The common grounds of anatomic structures, the anatomic responses to endocrine stimuli, the interrelationships and interdependencies of the endocrines and external stimuli have been followed and have been related to cellular permeability and hyaluronic acid. Cellular phases, including the rhythmic alternations in physiologic functions, have been delineated and their importance stressed. Further, the probability is advanced that this rhythmicity originates physiologically in the brain but that the brain itself is capable of receiving transmissions from within and without the body, and disseminating them, again rhythmically, in normal or altered amplitude and frequency. Further experimental evidence of these correlations and their practical extrapolations into drug actions and the therapy of infections and metabolic disease will be reported and will include clinical, animal and in vitro studies. At present, the following conclusions seem justified: 1. No component of the body is capable of independent action. 2. Action in any component is reflected, according to its magnitude and directness of application, upon all the body. 3. All such actions are mediated by the brain. 4. There is a dynamic, rhythmic cyclicity in physiologic action which can be altered in amplitude and frequency. 5. These rhythms are alternations of cellular tenseness and relaxation. 6. The concomitants of the tense phase are compactness, impermeability, electric conductivity and contraction of all cells, and these characteristics might be described collectively as the factors operative in maturing the cell. The concomitants of the relaxed phase are laxness, permeability, electric resistance and expansion of all cells and are factors of growth. 7. The phase of tenseness is accompanied by an increase in certain hormonal activities and that of relaxation by an increase in others. 8. The hormones may be causes of the phase or the results of it. 9. Infectious disease cannot act as an extraneous agent capable of bringing its own engine into such a highly integrated mechanism but must act on the body through its ability to affect one of the body's mechanisms. 10. Drugs must act through the same channels available to disease. 11. Foods may contain, in addition to their caloric content, components capable of stimulating either the phase of cellular expansion or cellular compaction, particularly foods from the reproductive systems of plants or animals (milk, eggs, cereal, for example). 12. Vitamins each stimulate one phase and should be evaluated in terms of positive actions. 13. Inherent growth and maturation factors are not of fixed capacity in an individual but beyond certain limits must be supplied him or applied to him constantly. 14. The hormone most manifest in the tense phase is estrogen and so may be considered the maturation factor, and the one most manifest in the phase of relaxation or cell division is progesterone, which may be considered the growth factor.

Apollon Musagète

2018 ◽  
Author(s):  
Nancy Reynolds
Keyword(s):  
Twentieth Century ◽  
Turning Point ◽  
Igor Stravinsky ◽  
String Orchestra ◽  
George Balanchine ◽  
Clear Cut ◽  
Ballets Russes ◽  
Look Back ◽  
The One ◽  
New Phase

Apollon Musagète, premiered by Serge Diaghilev’s Ballets Russes in 1928, and most widely known since the 1950s as Apollo, is the oldest work by choreographer George Balanchine still in active repertoire. For its age alone the ballet is significant, but it also marked a new phase in the development of Balanchine’s artistic philosophy. In 1945 he wrote, "Apollo I look back on as a turning point. In its discipline and restraint … the score was a revelation. It seemed to tell me that I could dare not to use everything, that I too could eliminate. I began to see how I could clarify … by reducing what seemed to be multiple possibilities to the one which is inevitable" (Balanchine qtd in Lederman 1975: 81). Such was Balanchine’s influence that what was a turning point for him was also a turning point for ballet in the twentieth century. The score that so influenced Balanchine was composed, by Igor Stravinsky, for a small string orchestra. Diaghilev described it as "an amazing work, extraordinarily calm, and with greater clarity than anything he has so far done, [with] filigree counterpoint [a]round transparent, clear-cut themes, all in the major key; [it is] somehow music not of this world, but from somewhere above" (Diaghilev qtd in White 1979: 342).

Reliability assessment of system under a generalized cumulative shock model

2019 ◽  
Vol 234 (1) ◽  
pp. 129-137 ◽  
Author(s):  
Min Gong ◽  
Serkan Eryilmaz ◽  
Min Xie
Keyword(s):  
Reliability Assessment ◽  
Shock Model ◽  
External Shocks ◽  
Phase Type Distribution ◽  
Internal Factors ◽  
Reliability Characteristics ◽  
Shock Models ◽  
The One ◽  
Random Shocks ◽  
Real Practice

Reliability assessment of system suffering from random shocks is attracting a great deal of attention in recent years. Excluding internal factors such as aging and wear-out, external shocks which lead to sudden changes in the system operation environment are also important causes of system failure. Therefore, efficiently modeling the reliability of such system is an important applied problem. A variety of shock models are developed to model the inter-arrival time between shocks and magnitude of shocks. In a cumulative shock model, the system fails when the cumulative magnitude of damage caused by shocks exceed a threshold. Nevertheless, in the existing literatures, only the magnitude is taken into consideration, while the source of shocks is usually neglected. Using the same distribution to model the magnitude of shocks from different sources is too critical in real practice. To this end, considering a system subject to random shocks from various sources with different probabilities, we develop a generalized cumulative shock model in this article. We use phase-type distribution to model the variables, which is highly versatile to be used for modeling quantitative features of random phenomenon. We will discuss the reliability characteristics of such system in some detail and give some clear expressions under the one-dimensional case. Numerical example for illustration is also provided along with a summary.

scholarly journals Experimental investigation of leak hydraulics

2012 ◽  
Vol 15 (3) ◽  
pp. 666-675 ◽  
Author(s):  
M. Ferrante ◽  
C. Massari ◽  
E. Todini ◽  
B. Brunone ◽  
S. Meniconi
Keyword(s):  
Distribution Systems ◽  
Water Distribution ◽  
Network Models ◽  
Water Distribution Network ◽  
Experimental Tests ◽  
Pressure Control ◽  
Pipe Material ◽  
Governing Equations ◽  
The One ◽  
Definition Of

In recent decades the hydraulics of leaks, i.e. the definition of the relationships linking the hydraulic quantities in pipes with leaks, has received increasing attention. On the one hand, the definition of the relationship between the leak outflow and the relevant parameters – e.g. the leak area and shape, the pressure inside the pipe and outside the leak, and the pipe material – is crucial for pressure control and inverse analysis techniques. On the other hand, if the effect of the leakage on the governing equations is not taken into account, i.e. the loss of the flow axial momentum is not considered, significant errors can be introduced in the simulation of water distribution systems. In this paper, the governing equations for a pipe with a leak are derived. The basic equations, obtained within different approaches, are presented in a consistent formulation and then compared with the results of some experimental tests. The leak jet angle and other major features of the results are analysed. The estimated values of the parameters can be used in the water distribution network models when pipes with a diffuse leakage are considered.

Studies on the susceptibility of varieties of apple to the feeding of two strains of woolly aphis (Homoptera) and relation to the chemical content of the tissues of the host

1975 ◽  
Vol 26 (1) ◽  
pp. 157 ◽  
Author(s):  
GC Sen Gupta ◽  
PW Miles
Keyword(s):  
Amino Nitrogen ◽  
South Australia ◽  
The Other ◽  
Clear Cut ◽  
Chemical Content ◽  
The One ◽  
Different Parts

Two strains of woolly aphis have been demonstrated in South Australia, the one ('Blackwood strain') able to attack varieties of apple resistant to the other ('Clare strain'). Both strains display well-defined differences in the ease with which they can colonize different varieties of apple and different parts of any one variety. These differences tend to be related to the composition of the tissues with respect to α-amino nitrogen and phenolics, but the most clear-cut correlation is an inverse one between the susceptibility of tissues and the ratio of phenolics to α-amino nitrogen in the tissue.

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