Studies on pattern regulation in hydra

Development ◽  
1966 ◽  
Vol 16 (1) ◽  
pp. 105-122
Author(s):  
Gerald Webster
Keyword(s):  
Detailed Analysis ◽  
Original Position ◽  
Axial Gradient ◽  
Characteristic Features ◽  
Time Required ◽  
Pattern Regulation

In a previous paper (Webster & Wolpert, 1966a) it was shown that during regulation the time required for the determination of the dominant region, the hypostome, was dependent on the original position of the hypostome-forming region on the linear axis. Hypostome determination occurred more quickly from distal than from proximal regions, suggesting an axial gradient. As Spiegelman (1945) has pointed out, a gradient in time for determination is not sufficient for limited realization to occur in a regulative system (Webster & Wolpert, 1966a). In addition, some mechanism for suppressing potentialities is required. One of the characteristic features of a dominant region is that it inhibits the formation of a new dominant region (Huxley & de Beer, 1934), and earlier work on hydra (Rand, Bovard & Minnich, 1926) has presented some evidence for inhibition of distal regeneration by distal structures. This paper will be concerned with a detailed analysis of the factors controlling hypostome formation.

scholarly journals Positional information and pattern regulation in hydra: formation of the foot end

Development ◽  
1973 ◽  
Vol 30 (3) ◽  
pp. 727-740
Author(s):  
J. Hicklin ◽  
L. Wolpert
Keyword(s):  
Positional Information ◽  
Basal Disc ◽  
Time Required ◽  
Pattern Regulation

The time required for foot end formation increases with distance from the foot end. Using lateral grafting it was shown that both the peduncle and basal disc could induce a proximal axis when grafted into the gastric region. The time for foot end determination was shown to be about 4 h at the proximal end of the gastric region and to increase towards the head end. In general the determination of the foot end is similar to that of the head end.

Nucleic acid and protein synthesis and pattern regulation in hydra

Development ◽  
1969 ◽  
Vol 21 (1) ◽  
pp. 55-70
Author(s):  
S. G. Clarkson
Keyword(s):  
Protein Synthesis ◽  
Dna Synthesis ◽  
Experimental Approach ◽  
Direct Evidence ◽  
Animal Cells ◽  
Rna And Protein Synthesis ◽  
Metabolic Activities ◽  
Time Required ◽  
Pattern Regulation

In a previous paper (Clarkson, 1969) data were presented which indicate that hypostome determination is accompanied by a large and rapid burst of RNA synthesis, a slight stimulation of protein synthesis, and no increase in DNA synthesis. More direct evidence concerning the relative importance of these metabolic activities in hypostome determination is reported in this paper. The experimental approach made use of the transplantation test of Webster & Wolpert (1966) in conjunction with some inhibitors of DNA, RNA and protein synthesis, the rationale being that if these metabolic activities play important roles in the determination of the hypostome, then their inhibition would be expected to have severe effects on the time required for this process. Regarding the inhibitors, hydroxyurea (HU) inhibits DNA synthesis in a variety of animal cells without altering rates of formation of RNA or protein (Young & Hodas, 1964; Yarbro, Kennedy & Barnum, 1965; Schwartz, Garofalo, Sternberg & Philips, 1965).

Spatial behavior in romantic communication: comparative analysis in the Russian, English, and Spanish linguocultures

Litera ◽  
2021 ◽  
pp. 214-223
Author(s):  
Alina Sergeevna Zagrebelnaya
Keyword(s):  
Comparative Analysis ◽  
Great Britain ◽  
Detailed Analysis ◽  
Interpersonal Communication ◽  
Literary Text ◽  
Spatial Behavior ◽  
Depth Study ◽  
Characteristic Features

This article describes the concept of “romantic communication”, examines the linguocultural specificity of spatial behavior in the instances of romantic communication in Russian, English and Spanish linguocultures. It is demonstrated that the situations of romantic communication in the indicated linguocultures are characterized by certain spatial movements of the communicants depending on their communicative intentions. The relevance of the selected topic is substantiated by globalization processes and rapid building of contacts between Russia, Great Britain and Spain, which, in turn, bonds these linguocultures and makes requires their in-depth study in order to understand the peculiarities of representation of spatial behavior in the course of interpersonal communication. It is worth noting that there are different approaches towards studying the romantic discourse; assessment is given to the role of the kinesic components therein. The question on similarity and divergence of the proxemic components in romantic communication in the Russian, English and Spanish linguocultures remains debatable, and draws particular interests of the experts in the field of linguistics and linguoculturology, as well as the representatives of business spheres dealing with Russia, Great Britain and Spain in one or another way; it allows to better understand the purpose and use of spatial components in the communicative aspect. The scientific novelty of this research consists in determination of linguistic peculiarities of representation of spatial behavior in the instances of romantic communication in the Russian, English and Spanish linguocultures. As a result of the conducted analysis, the author identifies the key main verbal, nominative, and adjective constructions that represent proxemic components of romantic communication in the English, Russian, and Spanish languages. It is also underlined that the characteristic features of the romantic discourse are related not only to kinesics, but also proxemics, which gives a better perspective on the motives of behavioral specificity of the actors of romantic communication, as well as helps to identify the level of their closeness through detailed analysis of linguistic saturation of the literary text.

TO THE PROBLEM OF PHRASEOLOGICAL UNITS REFLECTION IN DICTIONARIES OF DIFFERENT TYPES

2020 ◽  
pp. 130-142
Author(s):  
Е.М. Григорьева
Keyword(s):  
Detailed Analysis ◽  
English Language ◽  
Sampling Method ◽  
Semantic Features ◽  
Continuous Sampling ◽  
Translation Equivalent ◽  
Different Types ◽  
Individual Source ◽  
Graphic Illustration ◽  
Characteristic Features

Постановка задачи. Статья посвящена детальному анализу фразеологизмов английского языка различных тематических групп и особенностям их регистрации в англо-английских и англо-русском словарях и справочных пособиях. Рассматривается ряд характеристик, которые отличают фразеологические единицы от свободных словосочетаний. Кроме того, исследуется вопрос включения пословиц в состав фразеологического фонда того или иного языка. Впоследствии отобранные методом сплошной выборки фразеологические единицы классифицируются по различным основаниям, а также проводится детальный анализ особенностей их отражения в представленных изданиях. Результаты. Осуществляется классификация фразеологизмов по следующим категориям: функция в коммуникации, определяемая их структурно-семантическими особенностями, а также тематическое деление. Отдельно рассматриваются фразеологизмы-эвфемизмы, относящиеся к нескольким тематическим группам, среди которых смерть, ругательства и беременность. Выделяются и описываются характерные особенности организации микроструктуры (словарной статьи) каждого отдельно взятого издания. Выводы. На основании проведенного анализа регистрации английских фразеологизмов сделаны выводы о том, что данная лексика получает подробное и точное отражение в справочниках. Проведенный анализ теоретической литературы показал правомерность включения пословиц во фразеологический фонд, поскольку они принадлежат к культурному наследию того или иного народа и воспроизводятся в речи в исходной форме. Тип и адресат справочника определяют особенности организации словарной статьи, а также компоненты, которые входят в нее (дефиниция, переводной эквивалент, иллюстративный пример, грамматическая, стилистическая, региональная и этимологическая пометы, графическая иллюстрация). Statement of the problem. The article is devoted to a detailed analysis of the phraseological units of the English language of various thematic groups and the features of their registration in the English-English and English-Russian dictionaries and reference books. Features that distinguish phraseological units from free phrases are studied. More than that, the question of belonging proverbs to phraseological stock is studied. Then phraseological units selected by the continuous sampling method are classified according to different grounds, and a detailed analysis of the features of their reflection in the analyzed sources is carried out. Results. Phraseological units are classified into some categories according to the following criteria: function in communication, determined by their structural and semantic features and thematic division. Phraseological units-euphemisms related to several thematic groups, including death, curse words and pregnancy are studied. The characteristic features of microstructure organization of each individual source are described. Conclusion. The analysis of English phraseological units registration showed that this lexis is reflected in dictionaries in a proper way. Theoretical literature analysis shows justification of proverbs inclusion into phraseological stock as they are a part of national cultural heritage and are reproduced in speech in the basic form. Further, the author comes to a conclusion that dictionary type and addressee of the reference book determine features of microstructure organization and their components (definition, translation equivalent, illustrative example, grammar, stylistic, regional and etymological labels, graphic illustration).

NMR Determination of the Structure of Peracetylated Icariside B2 from Veratrum Lobelianum BERNH.

1995 ◽  
Vol 60 (8) ◽  
pp. 1380-1385 ◽  
Author(s):  
Václav Suchý ◽  
Miloš Buděšínský ◽  
Karel Ubik ◽  
Daniel Grančai ◽  
Vlasta Földešiová
Keyword(s):  
Detailed Analysis ◽  
Nmr Spectra ◽  
Aerial Part ◽  
C Nmr

rel(1S,4S,5R)-3,3,5-Trimethyl-4-[( 1E)-3-oxo-1-butenyl]-4,5-epoxy-cyclohexyl-O-β-D-glucopyranoside (I) was isolated from the aerial part of Veratrum lobelianum BERNH. The structure was derived mainly from detailed analysis of 1H and 13C NMR spectra of its acetylated derivative II. Compound I has been already reported under the name icariside B2in Epimedium grandiflorum MORR. var. thunbergianum (MIQ.) NAKAI.

Mercury-204 Determination by Emission Spectroscopy

1965 ◽  
Vol 19 (3) ◽  
pp. 87-89 ◽  
Author(s):  
F. M. Smith
Keyword(s):  
Coefficient Of Variation ◽  
Isotope Shift ◽  
Emission Spectroscopy ◽  
Electrodeless Discharge ◽  
Discharge Lamp ◽  
Isotope Concentration ◽  
Single Determination ◽  
Time Required

The determination of mercury-204 was made by using the isotope shift of the 3984 A mercury line excited by electrodeless discharge. Densitometric traces were made from film recordings of the 3984 A line and the areas under the component peaks were determined. Ratios of each of these areas to the sum of the areas from all the line components are plotted against the isotope concentration to produce a working curve. The coefficient of variation for this method is approximately 11 percent The time required for a single determination (after fabrication of the discharge lamp) is about two hours.

A detailed analysis ofD-,D s - andB-meson transition form factors and the determination of |V cb |

1990 ◽  
Vol 48 (4) ◽  
pp. 663-671 ◽  
Author(s):  
J. G. Körner ◽  
K. Schilcher ◽  
M. Wirbel ◽  
Y. L. Wu
Keyword(s):  
Detailed Analysis ◽  
Form Factors ◽  
Transition Form

scholarly journals THE EFFECTS ON BIOLOGICAL MATERIALS OF FREEZING AND DRYING BY VACUUM SUBLIMATION

1954 ◽  
Vol 100 (1) ◽  
pp. 81-88 ◽  
Author(s):  
Donald Greiff ◽  
Henry Pinkerton
Keyword(s):  
Influenza Virus ◽  
Biological Materials ◽  
Continuous Operation ◽  
Virus Suspension ◽  
Vacuum Sublimation ◽  
End Point ◽  
Different Temperatures ◽  
Time Required

A vacuum sublimation apparatus is described which will permit, (a) the removal of water from virus suspensions at temperatures ranging down to –80°C., (b) continuous operation with a minimum of attention from the investigator, (c) sealing off of samples at operating pressures (10–5 mm. Hg), (d) simultaneous lyophilization of aliquot samples at different temperatures, (e) isolation of a portion of the apparatus without disturbing the remainder of the system, and (f) determination of the end-point of sublimation without disturbing the samples. The time required for drying 0.1 ml. of influenza virus suspension was shown to increase markedly with decrease of temperature, 8 days being required for dehydration at –80°C. in contrast to 2 days at –30°C. and 1 day at 0°C.

Positional information and pattern regulation in Hydra. Dynamics of regions at the boundary

Development ◽  
1975 ◽  
Vol 33 (2) ◽  
pp. 499-510
Author(s):  
J. Hicklin ◽  
A. Hornbruch ◽  
L. Wolpert
Keyword(s):  
Positional Information ◽  
Boundary Region ◽  
The Times ◽  
Pattern Regulation ◽  
Cut Surface

The dynamics of boundary regions have been investigated mainly by axial grafting and with the emphasis on the head end. The time to lesist inhibition of head-end formation and the ability to inhibit head-end formation have been assayed under a variety of conditions. The times increase with distance from the head end. The times required by a boundary region to acquire the inhibitory properties of a head end are longer than those required to acquire resistance to inhibition. Determination of a head end is faster at a cut surface and at higher temperatures. The results are discussed in terms of a model involving two gradients. Some anomalous results are reported.

scholarly journals Panel Report on eu—Biodiesel: A Glass Half Full?—Implications for the Rising Issue of “Particular Market Situation”

2016 ◽  
Vol 2 (2) ◽  
pp. 142-163 ◽  
Author(s):  
Weihuan Zhou ◽  
Andrew Percival
Keyword(s):  
Detailed Analysis ◽  
World Trade ◽  
World Trade Organisation ◽  
Normal Value ◽  
Panel Report ◽  
The World ◽  
Market Situation ◽  
Positive Step

This article provides a detailed analysis of the World Trade Organisation (“wto”) panel report on the eu—Biodiesel dispute which represents the latest development of the wto jurisprudence on anti-dumping. The panel’s decision has significant implications for the rising use of Particular Market Situation (“pms”) by traditional users of anti-dumping (such as Australia) against economies like China in anti-dumping investigations. The panel correctly established that a finding of pms does not provide a sufficient ground for the use of surrogate costs in the determination of constructed normal value (“cnv”) and that the use of that methodology would result in the imposition of anti-dumping duties in excess of dumping margins that should have been established consistently with the wto Anti-Dumping Agreement, that is, by using actual costs recorded by exporters under investigation. It is argued that both Australia’s anti-dumping laws which essentially authorise the use of surrogate costs in the construction of normal value solely based on a finding of pms and Australia’s use of that methodology in practice are contrary to wto rules. The panel’s decision, therefore, is a positive step toward the resolution of the issues related to pms by imposing constraints on the use of a protectionist methodology in determining cnv so as to prevent unjustified inflation of dumping margins and anti-dumping duties.

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