Changes in the distribution of gap junctions inDrosophila melanogaster wing discs during the third larval and early pupal stages of development

1984 ◽  
Vol 193 (4) ◽  
pp. 187-196 ◽  
Author(s):  
Jan Stephen Ryerse ◽  
Barbara Ann Nagel
Keyword(s):  
Gap Junctions ◽  
Stages Of Development ◽  
The Third ◽  
Wing Discs

Quantitative EM of gap junction distribution in mutant drosophila wing discs

1983 ◽  
Vol 41 ◽  
pp. 720-721
Author(s):  
J.S. Ryerse
Keyword(s):  
Gap Junctions ◽  
Growth Control ◽  
Intercellular Junctions ◽  
Wing Disc ◽  
En Bloc ◽  
Metabolic Cooperation ◽  
Drosophila Wing ◽  
Adult Wing ◽  
Wing Discs ◽  
Wing Pouch

Gap junctions are intercellular junctions found in both vertebrates and invertebrates through which ions and small molecules can pass. Their distribution in tissues could be of critical importance for ionic coupling or metabolic cooperation between cells or for regulating the intracellular movement of growth control and pattern formation factors. Studies of the distribution of gap junctions in mutants which develop abnormally may shed light upon their role in normal development. I report here the distribution of gap junctions in the wing pouch of 3 Drosophila wing disc mutants, vg (vestigial) a cell death mutant, 1(2)gd (lethal giant disc) a pattern abnormality mutant and 1(2)gl (lethal giant larva) a neoplastic mutant and compare these with wildtype wing discs.The wing pouch (the anlagen of the adult wing blade) of a wild-type wing disc is shown in Fig. 1 and consists of columnar cells (Fig. 5) joined by gap junctions (Fig. 6). 14000x EMs of conventionally processed, UA en bloc stained, longitudinally sectioned wing pouches were enlarged to 45000x with a projector and tracings were made on which the lateral plasma membrane (LPM) and gap junctions were marked.

scholarly journals DEPARTMENT OF GEOMORPHOLOGY AND PALEOGEOGRAPHY OF THE IVAN FRANKO NATIONAL UNIVERSITY OF LVIV: STAGES OF DEVELOPMENT, ACHIEVEMENTS AND CHALLENGES

2020 ◽  
pp. 3-29
Author(s):  
Yaroslav Kravchuk ◽  
Ivan Kovalchuk ◽  
Lidiya Dubis
Keyword(s):  
Rapid Development ◽  
Research Direction ◽  
Environmental Research ◽  
Scientific School ◽  
Stages Of Development ◽  
Gis And Remote Sensing ◽  
Geomorphological Mapping ◽  
The Third ◽  
School Research ◽  
National University

This year we celebrate the 70th anniversary of the Department of Geomorphology (since 2000 – Geomorphology and Paleogeography) of the Faculty of Geography, Ivan Franko National University of Lviv, formed on the basis of the existing Lviv school of geography, which possessed old traditions and scientific achievements in the research of relief, in particular, of its development and formation. On the occasion of the anniversary, the article attempts to analyze the main achievements of the Department over the 70-year period, to highlight the main stages of its development and to outline the new challenges facing the Department today. There is the “Engineering, ecological and regional geomorphology” scientific school successfully functioning at the Department. Within its borders, the “Paleogeography of the Pleistocene” research direction is rapidly developing with significant achievements recognized at the international level. Anthropogenic and dynamic geomorphology, historical and geographical research, and geomorphological mapping with the use of GIS and remote sensing have been intensively developed. Over the last decade, research on the environmental issues, including spatial planning and design of nature reserves and ecological networks, as well as the study of geoheritage, geotourism and geoeducation have been singled out into independent areas. Overall, there are four development stages of the Department: the first ‒ from its foundation (1950) till 1970, the second ‒ during 1971-1990, the third ‒ during 1990-2010, and the fourth ‒ from 2010 till present. For each of them, the main scientific and practical achievements of the Department are briefly analyzed. The most important event in the first stage was the launching of fundamental comprehensive regional research, including the Ukrainian Carpathians, under the supervision of P. Tsys; in the second one ‒ the development of regional and engineering-geomorphological research and the introduction of stationary and semi-stationary research of modern relief-forming processes for the first time in Ukraine; in the third one ‒ the formation of a research school of engineering, ecological and regional geomorphology and the rapid development of Pleistocene paleogeography, as well as of environmental research; in the fourth one ‒ active development of the “Engineering, Ecological and Regional Geomorphology” scientific school and of the “Pleistocene Paleogeography” research direction, as well as of the investigations related to geoheritage, geotourism and geoeducation. The main current challenges are outlined at the end of the article. Key words: geomorphology; paleogeography; stages of development; scientific school; research directions; research; achievements; challenges.

Floral development of Aponogeton natans and A. undulatus

1977 ◽  
Vol 55 (9) ◽  
pp. 1106-1120 ◽  
Author(s):  
V. Singh ◽  
R. Sattler
Keyword(s):  
Cell Division ◽  
Developmental Stage ◽  
Floral Development ◽  
Developmental Stages ◽  
Point Of View ◽  
Stages Of Development ◽  
The Third ◽  
Procambial Strand ◽  
Tunica Layer

The primordia of the floral appendages are initiated in an acropetal succession. Members of the same whorl appear nearly simultaneously. The gynoecial whorl and the two staminal whorls are trimerous, whereas the perianth consists only of two anteriolateral tepals. However, the posterior (adaxial) tepal may be present as an extremely reduced buttress whose growth becomes arrested immediately after its inception. If this somewhat questionable tepal rudiment is included we have a perfectly trimerous and tetracyclic flower with alternation of successive whorls. Subtending bracts of the flowers are completely missing in all developmental stages. While the tepal primordia are dorsiventral from their inception, the stamen and pistil (carpel) primordia originate as hemispherical mounds which become dorsiventral in subsequent stages of development. Each pistil (carpel) primordium becomes horseshoe shaped. As the margins grow up and contact they fuse postgenitally. No cross zone is formed. Placentation is submarginal. In A. natans eight ovules are formed and in A. undulatus only two arise; all ovules are bitegmic. The floral apices have a two-layered tunica up to the stage of pistil formation. The inception of all floral appendages (including the ovules) occurs by periclinal cell division in the second tunica layer. The third layer (corpus) may contribute to the formation of the stamens and pistils. Each appendage primordium receives only one procambial strand which begins to differentiate after the inception of the primordium. The questionable rudimentary tepal buttress lacks a procambial strand. Apparently it does not reach the developmental stage at which procambial induction occurs. From the point of view of floral development, the two species of Aponogeton differ drastically from members of the Alismatales studied so far. Among the Helobiae, the Aponogetonaceae appear to be most closely related to the Scheuchzeriaceae and the Juncaginaceae (Triglochinaceae).

Stages of Development of the Soviet Statehood of 1917—1940 and their Estimation in Works of Soviet Scientists

10.12737/4830 ◽  
2014 ◽  
Vol 2 (7) ◽  
pp. 117-126
Author(s):  
Татьяна Шуберт ◽  
Tatyana Shubert
Keyword(s):  
Working Class ◽  
State Building ◽  
The State ◽  
Stages Of Development ◽  
Constitutional Development ◽  
Soviet State ◽  
The Third ◽  
Third Stage ◽  
Russian Constitution ◽  
Three Stages

In this article the three stages of development of the Russian Constitution (1918, 1925, 1937), are discussed each of represents a certain phase of the constitutional development of the Soviet state. The first stage (1917—1925) is characterized with the transition from capitalism to socialism, the second one stages (1925—1937) is associated with the adoption of the Constitution of the RSFSR in 1925, reflecting changes in the state-building — the formation of the unanimous union of the republican states — the USSR and delegating some mostly important items to it, the formation of the new autonomous regions, the end of the civil war and the reconstruction of the national economics. The third stage (1937—1940) is connected with the adoption of the Constitution of the RSFSR in 1937 (based on the Stalin Constitution of the USSR), which was characterized with the victory of socialism, the industrialization of the country and the collectivization in the agriculture, sphere of economics, the construction of a society without exploiting classes based on the alliance of the working class and the peasantry.

scholarly journals Demonstration of chromatinic structures in avian tubercle bacilli in the early stages of development

1947 ◽  
Vol 45 (4) ◽  
pp. 413-416 ◽  
Author(s):  
E. M. Brieger ◽  
C. F. Robinow
Keyword(s):  
Hydrochloric Acid ◽  
Early Development ◽  
The Other ◽  
Feulgen Reaction ◽  
Cytological Investigation ◽  
Stages Of Development ◽  
The Third ◽  
Early Stages ◽  
Other Hand ◽  
The Masses

In a cytological investigation of three branching and two non-branching strains grown on Loewenstein medium, it was found that avian tubercle bacilli contain chromatinic material which gives a positive Feulgen reaction and is readily stainable with Giemsa's solution after treatment of the fixed bacteria with hydrochloric acid.Growing filamentous forms of both ‘bacterial’ and ‘mycelial’ strains from 1 to 2 day old cultures contain variable numbers of irregularly spaced, more or less spherical chromatinic bodies which vary in staining in the same bacillus, some being red, others purple. During the third or fourth day the chromatinic material in the bacteria increases very much until most of it is fused into an almost homogeneous deeply stained column. In thenon-branchingstrains the filamentous forms with high chromatin content soon break up into small mono-or binucleate elements, and the same holds true for the ‘straight’ filamentous forms which are also present in cultures of branching strains. The ‘mycelial’ forms, on the other hand, disintegrate at this time (fourth or fifth day of cultivation), and it is uncertain whether they contribute (by partial fragmentation) to the masses of small mono- or binucleate forms which are the predominant element in old cultures of all the strains investigated.The chromatinic structures of avian tubercle bacilli have the same staining properties as those of ordinary non-acid-fast bacteria but differ from them in their behaviour during the early development of the bacilli.

scholarly journals EFFECT OF TRANSPLANTING PETUNIA PLUGS AT DIFFERENT STAGES OF DEVELOPMENT

HortScience ◽  
1990 ◽  
Vol 25 (9) ◽  
pp. 1084f-1084
Author(s):  
David S. Koranski ◽  
Chad G. Ingels
Keyword(s):  
Growth And Development ◽  
Root Damage ◽  
Optimum Growth ◽  
Stages Of Development ◽  
The Third

Petunia seeds of `White Cascade', `Red Flash', and `Red Madness' were sown in 406 plug trays on the same date. The first transplanting occurred when the plants could be removed from the cells without root damage. Subsequent transplanting occurred for four weeks. The first transplanting of `White Cascade' flowered two weeks earlier than the second while the third transplanting was one week behind the second. `Red Flash' flowered two weeks earlier for the first transplanting. There was no effect on time to flower for the `Red Madness'. The highest fresh and dry weights corresponded to the earliest flowering transplants. Optimum growth and development for most petunia cultivars was obtained with the earliest transplanting without root damage.

scholarly journals Idea and Models of Civil Society: Development Tendencies, Arguments Pro and Con

wisdom ◽  
2016 ◽  
Vol 2 (7) ◽  
pp. 95
Author(s):  
Hovhannes HOVHANNISYAN
Keyword(s):  
Civil Society ◽  
Third Sector ◽  
Stages Of Development ◽  
Harmonious Development ◽  
Civic Society ◽  
The Third ◽  
The Third Sector ◽  
Civil Society Development ◽  
Partnership Models

The article presents the main stages of development and major modifications of the idea of civil society from Greek and Roman antique philosophy to modern researchers. It discusses two – broad (philosophical) and narrow (the third sector of organizing civil society) – perceptions of civil society and proposes corresponding definitions. Etatistic (controlled), liberal, conflicting, partnership, segmentational and linked models of civil society are analyzed. The expediency of linked and partnership models is substantiated from the position of security and harmonious development of the civic society.

scholarly journals EU financial accounts reports

10.5912/jcb96 ◽  
2004 ◽  
Vol 10 (4) ◽  
Author(s):  
Colin Aaronson
Keyword(s):  
Research And Development ◽  
Disease Control ◽  
Smallpox Vaccine ◽  
Biotechnology Company ◽  
Stages Of Development ◽  
The Third ◽  
The Us ◽  
Development Expenditure ◽  
Control And Prevention ◽  
Centers For Disease Control

Acambis is a profitable and cash-generative biotechnology company that is focused on building a substantial franchise in the vaccine space. Its results for the period have benefited significantly from its contract to supply 155 million doses of its ACAM2000 smallpox vaccine to the US Centers for Disease Control and Prevention (CDC). During the year ended 31st December, 2003, Acambis generated profit before taxation (before exceptional items) of £46.8m on sales of £169.1m compared with a profit of £9.6m on sales of £79.7m for the whole of 2002. The pre-tax profit for the year was £39.4m, after taking account of an exceptional cost of £7.4m following a settlement with BTG International Limited to discharge all rights and obligations under a technology licence agreement established in 1994. The profit was earned mainly in the third quarter, with £22.2m earned during the three months ended 30th September, 2003, the company having earned £20.6m for the six months ended 30th June, 2003. Research and development expenditure increased from £16.5m in 2002 to £19.1m in 2003, the result of the progression of the company's products to the later stages of development.

EPIDEMIOLOGY IN MODERN UNDERSTANDING

2021 ◽  
Author(s):  
Валерий Петрович Невзоров ◽  
Татьяна Михайловна Буланова ◽  
Вячеслав Владимирович Пырву ◽  
Алиса Максимовна Кенда
Keyword(s):  
Pathological Process ◽  
Stages Of Development ◽  
Epidemic Process ◽  
Second Stage ◽  
The Third ◽  
Third Stage ◽  
Medical Diagnostic ◽  
Three Stages

Рассмотрены три этапа развития эпидемического процесса, где первый представлен фазами: профилактической, лечебно-диагностической и местно-резервной. Второй этап представлен дополнительной внешне-резервной фазой, а третий этап - фазой административного резерва. Такая связь отражает характеристики общего патологического процесса массовой заболеваемости неинфекционного генеза и ориентирует на мероприятия его ликвидации. Three stages of development of epidemic process where the first is presented by phases are considered: preventive, medical-diagnostic and local-reserve. The second stage is presented additional externally - a reserve phase, and the third stage - a phase of an administrative reserve. Such communication reflects characteristics of the general pathological process of mass incidence of noninfectious genesis and focuses on actions of its elimination.

Developmentally related changes in the production and expression of endo-β-1,4-glucanases in Aspergillus nidulans

Genome ◽  
1989 ◽  
Vol 32 (2) ◽  
pp. 288-292 ◽  
Author(s):  
P. S. Bagga ◽  
S. Sharma ◽  
D. K. Sandhu
Keyword(s):  
Aspergillus Nidulans ◽  
The Other ◽  
Wild Type ◽  
Stages Of Development ◽  
Experimental Conditions ◽  
The Third ◽  
Developmental Mutants ◽  
Mutant Strains ◽  
In The Wild ◽  
Low Levels

The production and electrophoretic expression of endoglucanase(s) were compared in the wild-type and three developmental mutants of Aspergillus nidulans. In the wild type, the production of endoglucanase and its distribution in extracellular and intracellular fractions varied with the age of the culture and the yield was better in stable cultures (production of conidia and cleistothecia) as compared with shake cultures (vegetative hyphae only). Two developmental mutants, aco-T69 and aco-40, which lack the development of conidia and cleistothecia, produced low levels of endoglucanase enzymes as compared with the wild type grown under similar conditions. On the other hand, in aco-90, a mutant capable of producing cleistothecia but no conidia, endoglucanase production was better. The results indicate a correlation between cleistothecial development and endoglucanase level. The electrophoretic studies revealed the presence of three forms of endoglucanase, i.e., EGI, EGII, and EGIII. The first two were detectable in the wild type as well as in mutant strains when grown under various experimental conditions and at all the stages of development. However, the third form could be observed only during cleistothecial development, indicating that this isozyme is developmentally regulated.Key words: endoglucanases, development, Aspergillus nidulans.

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