Local accumulation of Feulgen-positive granules in the egg cortex of Dentalium dentale L.

Development ◽  
1970 ◽  
Vol 23 (1) ◽  
pp. 245-252
Author(s):  
Lucy P. M. Timmermans ◽  
W. L. M. Geilenkirchen ◽  
N. H. Verdonk
Keyword(s):  
Polar Lobe ◽  
Apical Tuft ◽  
The Third ◽  
The One ◽  
Local Accumulation ◽  
Egg Cortex

A special feature of eggs of several species of annelids and molluscs is the formation of a polar lobe at stage-specific intervals during the cleavage phase. In the scaphopod Dentalium, a polar lobe develops at the first, the second and the third cleavage (Wilson, 1904). The cytoplasm set apart in the polar lobes is ultimately confined to the D blastomere and its derivative cells. Wilson observed that after removal of the polar lobe at the first cleavage a larva develops which lacks an apical tuft and the post-trochal region. After removal of the polar lobe at the second cleavage a larva develops which lacks most of the post-trochal region but possesses an apical tuft. A similar result to the one following the removal of the first polar lobe is obtained by removal of the vegetal one-third of an unfertilized egg.

Experimental studies on morphogenetic factors localized in the first and the second polar lobe of Dentalium eggs

Development ◽  
1970 ◽  
Vol 23 (1) ◽  
pp. 237-243
Author(s):  
W. L. M. Geilenkirchen ◽  
N. H. Verdonk ◽  
L. P. M. Timmermans
Keyword(s):  
Mytilus Edulis ◽  
Experimental Studies ◽  
Ilyanassa Obsoleta ◽  
Polar Lobe ◽  
Apical Tuft ◽  
The Third ◽  
Vegetal Pole ◽  
Morphogenetic Factors

During the development of several annelids and molluscs, a lobe of protoplasm is observed to protrude from the vegetal pole of the egg during the first cleavages. Removal of this polar lobe causes characteristic defects in the developing larvae as has been observed in the scaphopod, Dentalium (Wilson, 1904; Verdonk, 1968), the annelid Sabellaria (Hatt, 1932; Novikoff, 1938), the gastropod Ilyanassa obsoleta (Crampton, 1896; Clement, 1952) and the lamellibranch, Mytilus edulis (Rattenbury & Berg, 1954). In Dentalium a polar lobe is formed at the first, the second and the third cleavage. The lobes contain part of the cytoplasm, which later is confined to the D blastomere. After removal of the first polar lobe, embryos develop in which the post-trochal region and the apical tuft are absent. After removal of the second polar lobe the post-trochal region of the embryos is greatly reduced, but they develop an apical tuft (Wilson, 1904).

Alkohol im Tank – Bio-Kraftstoffe und die Grenzen moderner Mobilität

2004 ◽  
Vol 34 (136) ◽  
pp. 455-468
Author(s):  
Hartwig Berger
Keyword(s):  
Third World ◽  
Fossil Fuel ◽  
Energy Resources ◽  
The Third ◽  
Political Conflicts ◽  
The Future ◽  
Long Time ◽  
Food Market ◽  
The One ◽  
The Third World

The article discusses the future of mobility in the light of energy resources. Fossil fuel will not be available for a long time - not to mention its growing environmental and political conflicts. In analysing the potential of biofuel it is argued that the high demands of modern mobility can hardly be fulfilled in the future. Furthermore, the change into using biofuel will probably lead to increasing conflicts between the fuel market and the food market, as well as to conflicts with regional agricultural networks in the third world. Petrol imperialism might be replaced by bio imperialism. Therefore, mobility on a solar base pursues a double strategy of raising efficiency on the one hand and strongly reducing mobility itself on the other.

Al-Rasm al-ʿUthmānī: Towards Correct Pronunciation and the Preclusion of Ambiguity

2011 ◽  
Vol 13 (2) ◽  
pp. 201-171
Author(s):  
Nāṣir Al-Dīn Abū Khaḍīr
Keyword(s):  
Specific Pattern ◽  
Writing Style ◽  
The Third ◽  
The Past ◽  
Different Ages ◽  
Correct Pronunciation ◽  
The One ◽  
The Mind

The ʿUthmānic way of writing (al-rasm al-ʿUthmānī) is a science that specialises in the writing of Qur'anic words in accordance with a specific ‘pattern’. It follows the writing style of the Companions at the time of the third caliph, ʿUthmān b. ʿAffān, and was attributed to ʿUthmān on the basis that he was the one who ordered the collection and copying of the Qur'an into the actual muṣḥaf. This article aims to expound on the two fundamental functions of al-rasm al-ʿUthmānī: that of paying regard to the ‘correct’ pronunciation of the words in the muṣḥaf, and the pursuit of the preclusion of ambiguity which may arise in the mind of the reader and his auditor. There is a further practical aim for this study: to show the connection between modern orthography and the ʿUthmānic rasm in order that we, nowadays, are thereby able to overcome the problems faced by calligraphers and writers of the past in their different ages and cultures.

Detection and representation of the basic peculiarities of vegetation cover by the mapping method (experience based on a research of goltsy-taiga territories)

2013 ◽  
pp. 32-47
Author(s):  
S. V. Osipov
Keyword(s):  
Vegetation Cover ◽  
Mapping Method ◽  
Vegetation Changes ◽  
Large Classes ◽  
High Rise ◽  
The Third ◽  
Altitudinal Belts ◽  
The One ◽  
Dynamic Series ◽  
River Valleys

Geobotanical mapping of the territory in riverheads Bureya of 4500 sq.km is carried out and the map of a actual vegetation cover of scale 1 : 200 000 is prepared. The legend of the map is presented in the form of the text with three-level hierarchy of classes. At the heart of structure of a legend of the map such regularities of a vegetation cover, as its latitudinal zonality / altitudinal belts, situation in a relief and dynamic series lie. The largest divisions of the legend reflect, first, change of large classes of mesocombinations of vegetation at the level of belts and, secondly, distinction in a boreal - forestry belt between a vegetation cover of tops and slopes of mountains, on the one hand, and the bottoms of river valleys, with another. Divisions of the legend of the second level reflect, first, vegetation changes in the form of high-rise and barrier changes of subbelts, secondly, distinctions of a vegetation cover in different geomorphological conditions (small and average river valleys, northern slopes, etc.). Divisions of the legend of the second level correspond to dynamic series of units of the third level. Essential addition to it are block diagrams of dynamics of a vegetation cover.

Introduction

2017 ◽  
Author(s):  
Patrick Colm Hogan
Keyword(s):  
Queer Theory ◽  
Social Constructionism ◽  
The Other ◽  
Sexual Identities ◽  
The Third ◽  
Sexuality And Gender ◽  
And Gender ◽  
Sexual Part ◽  
The One ◽  
And Behavior

The introduction first sets out some preliminary definitions of sex, sexuality, and gender. It then turns from the sexual part of Sexual Identities to the identity part. A great deal of confusion results from failing to distinguish between identity in the sense of a category with which one identifies (categorial identity) and identity in the sense of a set of patterns that characterize one’s cognition, emotion, and behavior (practical identity). The second section gives a brief summary of this difference. The third and fourth sections sketch the relation of the book to social constructionism and queer theory, on the one hand, and evolutionary-cognitive approaches to sex, sexuality, and gender, on the other. The fifth section outlines the value of literature in not only illustrating, but advancing a research program in sex, sexuality, and gender identity. Finally, the introduction provides an overview of the chapters in this volume.

“A composItIon wrItten wIthout creatIve lImItatIons” – Wanda Landowska and concerto for harpsichord and five instruments by ManueL de Falla (1923)

2021 ◽  
Vol 1 (15) ◽  
pp. 67-107
Author(s):  
Ines R. Artola
Keyword(s):  
Strict Sense ◽  
Sonata Form ◽  
Historical Sources ◽  
Avant Garde ◽  
20Th Century Music ◽  
The Third ◽  
Word Analysis ◽  
The Past ◽  
History Of ◽  
The One

The aim of the present article is the analysis of Concerto for harpsichord and five instruments by Manuel de Falla – a piece which was dedicated by the composer to Wanda Landowska, an outstanding Polish harpsichord player. The piece was meant to commemorate the friendship these two artists shared as well as their collaboration. Written in the period of 1923-1926, the Concerto was the first composition in the history of 20th century music where harpsichord was the soloist instrument. The first element of the article is the context in which the piece was written. We shall look into the musical influences that shaped its form. On the one hand, it was the music of the past: from Cancionero Felipe Pedrell through mainly Bach’s polyphony to works by Scarlatti which preceded the Classicism (this influence is particularly noticeable in the third movement of the Concerto). On the other hand, it was music from the time of de Falla: first of all – Neo-Classicism and works by Stravinsky. The author refers to historical sources – critics’ reviews, testimonies of de Falla’s contemporaries and, obviously, his own remarks as to the interpretation of the piece. Next, Inés R. Artola analyses the score in the strict sense of the word “analysis”. In this part of the article, she quotes specific fragments of the composition, which reflect both traditional musical means (counterpoint, canon, Scarlatti-style sonata form, influence of old popular music) and the avant-garde ones (polytonality, orchestration, elements of neo-classical harmony).

Protein synthesis during Ilyanassa development: effect of the polar lobe

Development ◽  
1973 ◽  
Vol 29 (2) ◽  
pp. 267-281
Author(s):  
G. Teitelman
Keyword(s):  
Protein Synthesis ◽  
Normal Development ◽  
Disc Electrophoresis ◽  
Developmental Differences ◽  
Protein Solutions ◽  
Polar Lobe ◽  
Stages Of Development ◽  
Morphogenetic Factors ◽  
Slow Moving ◽  
The One

Removal of the polar lobe at the trefoil stage of the first cleavage division of Ilyanassa embryos causes abnormalities much later in development. To determine if the developmental differences between normal and delobed embryos were reflected in alterations in protein synthesis and at what stages of development these become evident, protein solutions were separated by disc electrophoresis on basic acrylamide gels. For the analysis of the newly synthesized proteins, two protein samples, one labelled with 14C and the other with 3H, were combined in the same electrophoretic column. Each was prepared from normal embryos or lobeless embryos at different stages of development. The distribution of the two groups of differentially labelled proteins was compared by a determination, for each fraction, of the ratio of the normalized 3H/14C counts for that particular fraction (R = 3H/14C). The plot of R versus fraction number was studied for various combinations of samples. During normal development the profile of labelled proteins remains unchanged until the onset of visible differentiation. At this stage, around day 4 of development, there are changes in biosynthesis revealed by a greater emphasis on the synthesis of slow moving proteins. The profile of labelled proteins of lobeless embryos remains unchanged up to the 5th day of development. This result is correlated with the absence, in the lobeless embryos, of many of the visible differentiations. Preliminary studies revealed that the spectrum of labelled proteins of the polar lobe is identical to the one present in lobeless embryos and in normal embryos in early stages of development. This suggests the possibility that the morphogenetic factors associated with the polar lobe are not among the newly synthesized proteins. A hypothesis is presented to account for the effects on morphogenesis and protein synthesis which are produced by removal of the polar lobe.

Introducing Morphology

2021 ◽  
Author(s):  
Rochelle Lieber
Keyword(s):  
Mental Lexicon ◽  
The Other ◽  
Morphological Data ◽  
Theoretical Frameworks ◽  
The Third ◽  
Hands On ◽  
Morphological Theory ◽  
Basic Concepts ◽  
The One

A lively introduction to morphology, this textbook is intended for undergraduates with relatively little background in linguistics. It shows students how to find and analyze morphological data and presents them with basic concepts and terminology concerning the mental lexicon, inflection, derivation, morphological typology, productivity, and the interfaces between morphology and syntax on the one hand and phonology on the other. By the end of the text students are ready to understand morphological theory and how to support or refute theoretical proposals. Providing data from a wide variety of languages, the text includes hands-on activities designed to encourage students to gather and analyse their own data. The third edition has been thoroughly updated with new examples and exercises. Chapter 2 now includes an updated detailed introduction to using linguistic corpora, and there is a new final chapter covering several current theoretical frameworks.

scholarly journals Health care logistics: mapping and optimization of patients logistics

2021 ◽  
Vol 12 (8) ◽  
pp. 2161-2179
Author(s):  
Daiane Maria de Genaro Chiroli ◽  
Raíza Conde Coradazi ◽  
Fabio Jose Ceron Branco ◽  
Yslene Rocha Kachba ◽  
Franciely Velozo Aragão ◽  
...  
Keyword(s):  
Linear Programming ◽  
Computational Simulation ◽  
Transportation Of Patients ◽  
Patient Transport ◽  
Specific Approach ◽  
Health Region ◽  
The Third ◽  
City Hall ◽  
Pass Through ◽  
The One

Healthcare logistics play an important role in management, being attributed the activities of acquisition, distribution and movement of materials, professionals and patients. This work aims to develop a study, using the healthcare logistics in the movement of patients in the third health region of Paraná, proposing a linear programming problem that will pass through a computational simulation, considering the existing demands and constraints in the system, aiming to optimize the flow of patients from this region. The present study developed four mathematical models, based on demands and constraints followed by linear programming in order to find the best possible solution for the flow of patients from the third health region of the state of Paraná. The study developed reached its goal of optimization, generating an economy in the transportation of patients. Through the analysis of the results, it is concluded that the model that best suits the presented problem is the one of costs minimization, since the one of vehicles presented higher costs. Possibly the model that minimizes the vehicles would bring better results if the vehicles were not outsourced, but of the Ponta Grossa City Hall (PMPG). Was possible to verify the importance of the theme, especially when referring to the flow of patients in the health services due to the lack of studies with this specific approach. Even with the scarcity of data, it is possible to notice the potential for improvements on this patient transport system.

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