Feather morphogenesis and feather pattern in normal and talpid3 mutant chick embryos

Development ◽  
1971 ◽  
Vol 25 (1) ◽  
pp. 65-83
Author(s):  
D. A. Ede ◽  
J. R. Hinchliffe ◽  
H. C. Mees

A comparative study of feather morphogenesis and the development of feather pattern in normal and talpid3 embryos has been carried out. The development of talpid3 CAM grafts shows that the effect of the gene is autonomous in the skin. The most striking effect of the gene upon feather morphogenesis is the failure of normal feather germ condensations to appear within the dermis. This is reflected in the abnormal distribution of alkaline phosphatase through the dermis. Dermal cells within and between condensations are not orientated in the mutant as they are in normal embryos, probably owing to the same defect in cell behaviour which causes condensation failure in talpid3 precartilage mesenchyme. The role of dermal cell orientation and movement in generating the overall feather pattern is examined in both normal and talpid3 embryos.

Development ◽  
1972 ◽  
Vol 28 (2) ◽  
pp. 313-341
Author(s):  
Par Annick Mauger

The role of somitic mesoderm in the development of dorsal plumage in chick embryos. I. Origin, regulation capacity and determination The role of somitic mesoderm in the development of the dorsal plumage has been studied in chick embryos. The operations were performed at 2–2·5 days of incubation. The replacement of a portion of somitic mesoderm by somitic mesoderm labelled with [3H]thymidine or obtained from Japanese quail embryos (whose nuclei bear distinctive specific markers) showed that cells originating from the dermatomes build up the dermis of the dorsal skin only. They do not migrate farther than approximately midway down the flank. Beyond this limit, dermal cells originate from the somatopleural mesoderm. The unsegmented somitic mesoderm is capable of extensive regulation, which leads to the development of a dorsal plumage, normal in the number and arrangement of its feathers according to the characteristic pattern of the spinal pteryla. Uni- or bilateral excision of segmented somitic mesoderm resulted in dorsal plumage deficiencies, the extent and frequency of which was related to the state of differentiation of the excised mesoderm. Thus, the excision of somites generally led to an incomplete spinal pteryla (absence of feather rows, apteria). However, the somitic mesoderm is still capable of regulation even though it has already undergone its differentiation into dermatome, myotome and sclerotome. These results show that somitic mesoderm retains its regulative capacity, even though it has already acquired its feather-forming determination. The replacement of unsegmented somitic mesoderm by various implants (agar, tantalum, gut, neural tube, somatopleural mesoderm), intended to block the regulation processes, abolished the differentiation of the spinal feathers on the operated side. In some cases, the implantation of somatopleural mesoderm resulted in the formation of a supernumerary tract. No tissue other than somitic mesoderm – not even the somatopleural mesoderm, which is normally in part feather-forming – is able to give rise to region-specific spinal pteryla dermis. The excision and replacement of somitic mesoderm prevented the differentiation of dense dermis, whereas these operations had no effect on the early histogenesis of the epidermis, with the formation of arches and anchor filaments.


2020 ◽  
Vol 28 (2) ◽  
pp. 298-318
Author(s):  
Roman Girma Teshome

The effectiveness of human rights adjudicative procedures partly, if not most importantly, hinges upon the adequacy of the remedies they grant and the implementation of those remedies. This assertion also holds water with regard to the international and regional monitoring bodies established to receive individual complaints related to economic, social and cultural rights (hereinafter ‘ESC rights’ or ‘socio-economic rights’). Remedies can serve two major functions: they are meant, first, to rectify the pecuniary and non-pecuniary damage sustained by the particular victim, and second, to resolve systematic problems existing in the state machinery in order to ensure the non-repetition of the act. Hence, the role of remedies is not confined to correcting the past but also shaping the future by providing reforming measures a state has to undertake. The adequacy of remedies awarded by international and regional human rights bodies is also assessed based on these two benchmarks. The present article examines these issues in relation to individual complaint procedures that deal with the violation of ESC rights, with particular reference to the case laws of the three jurisdictions selected for this work, i.e. the United Nations, Inter-American and African Human Rights Systems.


2000 ◽  
Vol 2 (1) ◽  
pp. 107-123 ◽  
Author(s):  
Muzaffar Iqbal

This article attempts to present a comparative study of the role of two twentieth-century English translations of the Qur'an: cAbdullah Yūsuf cAlī's The Meaning of the Glorious Qur'ān and Muḥammad Asad's The Message of the Qur'ān. No two men could have been more different in their background, social and political milieu and life experiences than Yūsuf cAlī and Asad. Yūsuf 'Alī was born and raised in British India and had a brilliant but traditional middle-class academic career. Asad traversed a vast cultural and geographical terrain: from a highly-disciplined childhood in Europe to the deserts of Arabia. Both men lived ‘intensely’ and with deep spiritual yearning. At some time in each of their lives they decided to embark upon the translation of the Qur'an. Their efforts have provided us with two incredibly rich monumental works, which both reflect their own unique approaches and the effects of the times and circumstances in which they lived. A comparative study of these two translations can provide rich insights into the exegesis and the phenomenon of human understanding of the divine text.


2020 ◽  
Vol 2020 ◽  
pp. 1457-1461
Author(s):  
Pantelitsa Yerimou ◽  
◽  
George Panigyrakis

Author(s):  
Баяманова М.С.

Summary: The article deals with the analysis of the interpretational field of the basic lexical units which represent the meaning of the concept “woman” in English and Kyrgyz languages and cultures. Comparative – contrastive analytical data of the most frequently used in both languages variants of the interpretation of the concept “woman” have been given. The semantic fields of nuclear and nearnuclear meanings of the lexical units, transforming the notion of “woman” in English and Kyrgyz languages and also the place and role of these notions in cultures and philosophy of the nations on the basis of mentality and traditional values have been studied and described. The situations of the use of this or that variant of the meaning of lexical unit. A comparative study of the definitions of the word “woman’ in English and Kyrgyz languages have been given. Key words: concept, woman, interpretational field, notion, definition, semantic field, culture, language, linguoculture, transformation Аннотация: В статье рассматриваются интерпретационные поля основных лексических единиц, репрезентирующих значение концепта «женщина» в английской и кыргызской лингвокультурах. Приводятся сравнительно-сопоставительные аналитические данные наиболее употребительных в речи обоих языков вариантов интерпретации концепта «женщина». Изучены и описаны семантические поля ядерных и околоядерных значений лексических единиц, трансформирующих понятие «женщина» в английском и кыргызском языке, а также роль и место этих понятий в культурах и философии народов на основе менталитета и традиционных ценностей. Приводятся ситуации использования того или ино- го варианта значения лексической единицы, проведено сравнительное изучение определений слова «женщина» в английском и кыргызском языках. Ключевые слова: концепт, женщина, интерпретационное поле, понятие, определение, семантическое поле, культура, язык, лингвокультура, трансформация Аннотация: Макалада англис жана кыргыз тилдеринде жана маданияттарында «аял» концептинин маанисин репрезентациалаган негизги лексикалык бирдиктер каралат. «Аял» концептин эки тилдеги кѳп колдонулуучу интерпретациялоо варианттарынын аналитикалык салыштырма маалыматтары изил- делип берилген. Англис жана кыргыз тилдеринде «аял» түшүнүгүн трансформациялаган лексикалык бирдиктердин түп нуска жана ага жакындашкан маанилери иликтелип каралган. Берилген түшүнүктѳрдүн элдик философиясында жана маданиятында, менталитеттин жана салттын негизинде эл арасына кеӊири тараган, элдик тилде жана маданиятта ойногон ролу менен орду чагылдырылган. Ар түрдү ситацияларда колдонулуучу тиги же бул лексикалык бирдиктердин маанисинин варианттары каралган, «аял» деген сѳздун англис жана кыргыз тилдериндеги түшүндүрмѳлѳрү салыштырылып изилделген. Түйүндүү сѳздѳр: концепт, аял, интерпретациялоо мейкиндиги, түшүнүк, түшүндүрмѳ, семантикалык чѳйрѳ, маданият, тил, лингвомаданият, трансформациялоо


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