Development and ultrastructure of the haustorium of Viscum minimum. I. The adhesive disk

1989 ◽  
Vol 67 (4) ◽  
pp. 1161-1173 ◽  
Author(s):  
H. S. Heide-Jørgensen

The adhesive disk of the haustorium of Viscum minimum Harvey develops an epithelium of uni- or bi-cellular secretory trichomes. Before contact with the host is obtained, the trichomes secrete adhesive cutinaceous material. This secretion contains fragments of the lamellar cuticle proper, the reticulate cuticular layer, and the noncutinized part of the cuticularized wall, in additions to pockets of granular material. The volume of the adhesive product per trichome may be several times the volume of the secretory cell itself except in front of the future intrusive organ where secretion is reduced. Formation of cutin cystoliths was observed in sections of wall of different ages within single trichomes. The trichomes are rich in mitochondria, plastids with starch, spherosomes, ribosomes, and ER that are associated with the strongly convoluted plasmalemma. A special type of tubular ER is described. Zones of collapsed cells are formed in the cortex as the apex of the wedge-shaped intrusive organ emerges. The cuticularized wall of the host then disintegrates, and the intrusive organ forms a fissure within the host. This becomes lined, to the depth of a few cells, partly with cuticularized and finally compressed cells originating from the adhesive epithelium, and partly with new cells produced by the intrusive organ. Key words: Viscum minimum, adhesive disk, adhesive epithelium, cuticle ultrastructure, cutin cystolith, haustorium, secretion.

2021 ◽  
Vol 28 ◽  

Some countries might witness movements that call for secession from the main homeland ,some had succeeded in their endeavors and others are hoping to accomplish them in the future .There are such movements in the Arab homeland which varied according to the motivations behind their wishes to disengage and the means that they used to accomplish them ,whether peaceful or by resort to violence ,which might take long time . These motives might be political, ethnical ,religious, or else . Usually there might be more than one motive behind such moves towards disengagement and secession, but the international support is the most conclusive factor in achieving such an aim , and this is what we are trying to discuss here. Key words : secession ,political, economic ,ethnic, minorities


2012 ◽  
Vol 33 ◽  
Author(s):  
Г. І. Матукова

У статті розкрито підхід до формування основ конкурентоспроможності фахівця сфери управління на засадах сучасних інтерактивних технологій навчання; показано можливості поетапної реалізації кейс-методу і його впливу на формування професійно важливих якостей майбутнього фахівця.Ключові слова: підприємництво, професійні якості, інтерактивне навчання, кейс-метод.  In articles approaches to formation of bases of competitiveness of the expert of sphere of management on starting positions of modern interactive technologies of training; it is shown possibility of stage-by-stage realization of a case-study and its influence on formation of professionally important qualities of the future expert. Key words: business, professional qualities, interactive training, a case- study.


2020 ◽  
Vol 60 (11) ◽  
pp. 143-146
Author(s):  
Parvana Ismayil Pashayeva ◽  

The article deals with the problems of introducing of time, time changes and the time-place relations as well. Artistic time is distinguished by belonging of an artistic time to the past in the artistic text, and in epos texts as well. In such kinds of texts one can meet with the changing of situations and various forms of substitutions of grammatical time. Speech moment can be used in defining of criteria for the present, past and the future times in epos texts. And speech moment is being connected with the physical time. Grammatical time comes into effect as a result of time pass components of physical time changings of course. Key words: time, place, epos, artistic time, grammatical time


10.14201/3165 ◽  
2009 ◽  
Vol 21 (1) ◽  
Author(s):  
Petra María Pérez Alonso-geta

RESUMEN: ntendemos la creatividad como destreza adquirible, como un rasgo del que participan todos los seres humanos, aunque precise ser cultivada. La capacidad de ser creativo es una mezcla de conocimientos, actitudes y habilidades que se pueden conseguir mediante la práctica. Se trata de hacerse con nuevas ideas, saliendo de las rutas trazadas, por la experiencia para conseguir nuevos productos. Desde la escuela es necesario estimular la creatividad para poder afrontar los retos que hoy se plantean, en los distintos ámbitos de la realidad, dando solución a los nuevos problemas. Eeducar para la creatividad es una estrategia de futuro. Palabras clave: creatividad, innovación, educación, creencias, actitudes.ABSTRACT: This paper conceives creativity as an acquirable skill, as a trait shared by every human being. Hhowever, creativity must be developed: the ability of being creative is a blend of knowledge, attitude and skills that can only be learnt through practice. It is about having new ideas and departing from habitual pathways traced by everyday experience in order to obtain new outputs. It is essential to stimulate creativity in school in order to be able to handle efficiently today’s new challenges, which present themselves in different areas of our lives. Teaching creativity is therefore a strategy for the future. Key words: creativity, innovation, education, knowledge, attitude.SOMMAIRE: Nous définissons la créativité comme une habilité que l’on peut atteindre, comme un attribut auquel tous les êtres humains participent, même si elle a besoin d’être cultivée. La capacité d’être créatif est un mélange de connaissances, d’attitudes et d’habilités que l’on peut atteindre moyennant la pratique. Il s’agît de trouver des nouvelles idées, en sortant des chemins existants, à travers l’expérience afin d’obtenir de nouveaux produits. Dès l’école il est nécessaire de stimuler la créativité pour pouvoir affronter les défis actuels, dans les différents domaines de la réalité en apportant des solutions aux nouveaux problèmes. Eenseigner la créativité, c’est une stratégie pour l’avenir.


Xihmai ◽  
2013 ◽  
Vol 5 (10) ◽  
Author(s):  
Jesús Ignacio Panedas Galindo

Resumen Cuando se empezaron a conocer los testimonios de los supervivientes de los campos de exterminio nazis, la humanidad se consternó. El sufrimiento provocado y la aplicación sistemática y consciente de la técnica a la destrucción de la persona, fueron descubrimientos que pusieron en alerta al hombre sobre la naturaleza del hombre mismo.   Tanto fue el horror que se alcanzó a entrever a través de las narraciones que el  tiempo  se  congeló.  El  reclamo  silencioso  de  las  auténticas  ví­ctimas, quienes murieron, se suspendió en el aire de la memoria hasta que los responsables reconocieran sus culpas. El olvido no podí­a abrazar tan profundos crí­menes.   Por este motivo no puede realizarse el fin de la historia. Los sufrimientos del hombre provocados hasta este grado por el mismo hombre fuerzan un pendiente que ya no puede borrarse. El grito de dolor recuerda a las generaciones futuras la necesidad de una reparación, del perdón, del reconocimiento.   Palabras Clave: Testimonio, memoria, campos de exterminio, fenomenologí­a, hermenéutica, sufrimiento, herencia.   Abstract When testimony from the survivors from Nazi extermination fields were first known, the human race filled with dismay. The suffering provoked and the systematic conscious application of the technique of destruction of the individual, were discoveries that alerted the individual on the nature of the individual itself.   Such a horror was seen through the narrations that time froze.     The silent demand from the authentic victims, who died, was suspended on the air of memory until the responsible recognized their  guilt. Obscurity could not hold such deep crimes.   For this reason the end of history cannot be made. The suffering of the individual provoked up to this point by the individual itself, force an unresolved point that cannot be erased.   The scream of pain reminds the future generations the need to repair, forgive and recognize it.   Key words: Testimony, memory, extermination fields, phenomenology, hermeneutics, suffering, inheritance.


2020 ◽  
Vol 9 (1) ◽  
pp. 147-169
Author(s):  
Gustavo Fornari Dall'Agnol

O presente artigo visa a explorar teoricamente o nível doméstico no programa de pesquisa do Realismo Neoclássico. Para tal, revisa-se o programa desde suas origens na década de 1990 até seu desenvolvimento mais atual, aqui analisado na obra de Ripsman, Lobell e Taliaferro (2016). Faz-se uma revisão crítica do emprego das variáveis domésticas, de maneira, aqui argumentada, indiscriminada e prejudicial ao futuro do programa de pesquisa. Ademais irá propor-se que o Realismo Neoclássico, como possível solução, reorganize as variáveis de nível doméstico empregadas em suas análises e construções teóricas, de maneira a dar primazia a variáveis mais ligadas à ontologia e epistemologia realista. Conclui-se que essa é uma maneira para superar as críticas feitas ao programa de pesquisa, que do ponto de vista do presente estudo, vem contribuindo decisivamente para o estudo da política internacional e pode continuar a fazê-lo.     Abstract: The present paper aims at theoretically exploring the domestic level in the Neoclassical Realist research program. In order to do so, it analyzes the program since its origins in the 1990 towards its most recent development, expressed by the work of Ripsman, Lobell and Taliaferro (2016). A critical review of the employment of domestic variables is realized, arguing that they are introduced in a non-systematic manner and are an obstacle for the future of the research program. Beyond that, it will be proposed, that Neoclassical Realism, as a possible solution, reorganizes its domestic level variables employed in their analysis and theoretical constructions, in a manner of giving primacy to variables closer to the realist ontology and epistemology. The conclusion is that this is one way of overcoming the critics towards the research program, which from the perspective of this work, has been contributing decisively to the study of international politics and can keep doing so. Key-words: Neoclassical Realism; Domestic Variables; Realpolitik.       Recebido em: junho/2019 Aprovado em: dezembro/2020


Author(s):  
Jorge Sierra Merchán

ResumenEn la discusión sobre las implicaciones éticas de la ingeniería genética, es común establecer una diferencia entre eugenesia negativa y eugenesia positiva. La eugenesia negativa está conformada por procedimientos orientados a corregir defectos genéticos, es decir, a evitar o minimizar la trasmisión de enfermedades hereditarias. La eugenesia positiva consiste en potenciar u optimizar caracteres que se consideran deseables (belleza o inteligencia). Una cosa es reparar, con fines terapéuticos, un error genético y otra cosa es mejorar genéticamente un rasgo que se considera bueno y deseable. En este sentido cabe preguntarse: ¿hay un deber moral de evitar, mediante la ingeniería genética, que los niños nazcan con discapacidades y no se les condene a una vida de desgracia? ¿O hay también un deber moral equivalente de garantizar que los niños posean belleza e inteligencia? El presente texto busca responder ambas cuestiones mediante una evaluación de los argumentos en pro y en contra de la eugenesia desarrollados por Singer y Nussbaum. Sostendré que hay una obligación moral de aplicar la eugenesia negativa, mientras que tal obligación no es extensiva para el caso de la eugenesia positiva. Esto implica que no es posible exigir un presunto derecho a ser desgraciado ni desde el punto de vista de los padres ni desde el punto de vista de los futuros hijos para el caso de la eugenesia negativa, en tanto que para el caso de la eugenesia positiva el derecho a ser desgraciados parece ser más defendible. Palabras clave: Eugenesia, genoma humano, principio preventivo, Singer, Nussbaum**********************************************************Is it possible to claim a alleged right to be disgraced? The “happy world” of eugenicsAbstractIn the discussion about the ethical implications of genetic engineering it is usual to distinguish between negative and positive eugenics. Negative eugenics refers to genetic imperfections correction procedures, which aim to avoid or minimize the transmission of hereditary diseases. Positive eugenics consists in the improvement or optimization of features considered desirable (as beauty or intelligence). One thing is to repair, for therapeutic purposes, a genetic error, and another to genetically improve a feature considered good and desirable. In this sense one could ask if it is a moral duty to avoid, through genetic engineering, impairments in newborns, saving them from an unfortunate life; and if there is also an equivalent moral duty to guarantee that children possess beauty and intelligence. This paper aims to answer both questions through an evaluation of the arguments for and against eugenics proposed by Singer and Nussbaum. I will hold that though there is a moral obligation to apply negative eugenics, this kind of obligation is not present in the case of positive eugenics. This implies that it is not possible to demand a presumed right to be miserable, either from the parent’s or the future children’s point of view, in the case of negative eugenics, although this presumed right to be miserable seems to be more defensible in the case of positive eugenics. Key words: Eugenics, human genome, preventive principle, Singer, Nussbaum.**********************************************************É possível reclamar um alegado direito a ser desgraçado? O “mundo feliz” da eugenesiaResumoNa discussão sobre as implicações éticas da engenharia genética é frequente estabelecer uma diferenciação entre eugenesia negativa e eugenesia positiva. A eugenesia negativa está conformada pelos procedimentos orientados a corrigir defeitos genéticos, ou seja, evitar ou minimizar a transmissão de doenças hereditárias. A eugenesia positiva consiste em potenciar ou aperfeiçoar caracteres que se consideram desejáveis (beleza ou inteligência). Uma coisa é reparar, com fins terapêuticos, um erro genético, e outra coisa é melhorar geneticamente um traço que se considera bom ou desejável, Nesse sentido é possível perguntar: há o dever moral de evitar, mediante a engenharia genética, que as crianças nasçam com incapacidades e não sejam condenados a uma vida de desgraça? Ou há também um dever moral equivalente de que as crianças possuam beleza e inteligência? O presente texto procura responder ambas as questões mediante uma avaliação dos argumentos em prol e em contra da eugenesia desenvolvidos por Singer e Nussbaum. Vou suster que há uma obrigação moral de aplicar a eugenesia negativa, enquanto que tal obrigação não é extensiva para o caso da eugenesia positiva. Isto implica que não é possível exigir um pressuposto direito a ser desgraçado nem desde o ponto de vista dos pais nem desde o ponto de vista dos futuros filhos no caso da eugenesia negativa, em tanto que no caso da eugenesia positiva o direito a ser desgraçados parece ser mais defendível. Palavras chave: Eugenesia, genoma humano, princípio preventivo, Singer, Nussbaum.


2001 ◽  
Vol 81 (4) ◽  
pp. 489-503 ◽  
Author(s):  
H H Janzen

Now, as a new century begins, may be a good time to reflect on the future of Soil Science on the Canadian prairies. One way to do that is to step back about one hundred years, to the turn of the previous century when our grassland soils were first cultivated. What questions perplexed scientists then? And how did they look for answers? My objective is to listen for our forebears’ thoughts in their writings, now largely buried. From this historical vantage may emerge insights, not only into where our science has been, but also into where it might yet go. Key words: Soil organic matter, crop rotation, grassland soils, history


1990 ◽  
Vol 68 (8) ◽  
pp. 1706-1711 ◽  
Author(s):  
Roberta Parish ◽  
Roy Turkington

The colonization of areas affected by molehills and dung pats was monitored in three adjacent pastures of different ages. Seedling establishment was infrequent, and most colonization took place by rhizomes, e.g., Agropyron repens and Poa compressa, or by stolons, e.g., Trifolium repens. Tillering species, e.g., Dactylis glomerata, Holcus lanatus, and Lolium perenne, were poor colonizers of disturbed areas. Invasion of gaps by a species was not proportional to its abundance in the pasture. Individual plants are eliminated at random by the disturbances. Small-scale disturbances tend to decrease community heterogeneity. Key words: disturbance, colonization, dung, molehill, pasture.


1987 ◽  
Vol 63 (3) ◽  
pp. 150-154
Author(s):  
J. Brian Nyberg

As young forests in many areas of Canada enter the middle and later stages of their rotations, new concerns are arising overt the future of deer populations. Analysis of silvicultural impacts on deer habitat requirements indicates that the food, cover, and water needs of deer can be met in young forests, but that most uniformly treated stands will be lacking in one more components. Mosaics of young stands, each 20–40 ha in area and at different stages of management, will provide good habitat in many areas. In areas with snowy winters, however, deer need to find all habitat components much more closely interspersed. Key words: Deer, Odocoileus hemionus, habitat requirements, winter range, intensive forestry, immature stands, old-growth, thermal cover, security cover, forage, lichens, silviculture.


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