370 research outputs found
Ozelenjavanje tubularnih kromoplasta u plodovima varijeteta Cucurbita maxima Duch cv. turbaniformis
In subepidermal cell layers of the red proximal part of fruits of Cucurbita maxima cv. turbaniformis the reversion of chromoplasts into chloroplasts has been investigated. Before the process of regreening the subepidermal cells contain only chromoplasts of the tubulous type. The chromoplasts are filled with a large peripheral reticulum, plastoglobules and numerous tubules.
During the process of regreening, the tubules and part of plastoglobules disappear, while new thylakoids are formed simultaneously. The thylakoids increase in number and form grana structures. The results of
the process of regreening are chloroplasts with normal grama structures and numerous, big plastoglobules. The investigations suggest that the material contained in the new thylakoids originates partially from tubules and plastoglobules, but is partially synthesized during the process of regreening. The observations are discussed with special reference to the origin of the newly formed thylakoids and grana.Istražena je pretvorba kromoplasta u kloroplaste u stanicama subepiderme crvenog proksimalnog dijela ploda varijeteta Cucurbita maxima Duch. cv. turbaniformis. Prije ozelenjavanja subepidermske stanice sadržavaju samo kromoplaste tubularnog tipa. Kromoplasti su ispunjeni s velikim perifernim retikulumom, plastoglobulima i brojnim tubulima.
Za vrijeme ozelenjavanja tubuli, a djelomiÄno i plastoglobuli, nestaju uz istodobni nastanak novih tilakoida. Broj tilakoida raste i nastaju grana. Rezultat ozelenjavanja su kloroplasti s normalnim granama, ali s mnogobrojnim plastoglobulima. Ta istraživanja upuÄuju na to da materijal za izgradnju novih tilakoida potjeÄe djelomiÄno iz tubula i plastoglobula, a djelomiÄno je bio sintetiziran tijekom procesa ozelenjavanja. Posebno je razmotren naÄin postanka novih tilakoida i grana
Pretvorbe plastida u bijelim plodovima bundeve
The development of plastids in the subepidermis of fruits of Cucurbita pepo var. patisson starts with the stage of normal proplastids. In the process of fruit ripening the proplastids are transformed into fully-grown leucoplasts, which are similar in ultrastructure to the chromoplasts of the globular type. In the process of fruit decaying the leucoplasts are completely disintegrated. The problem of plastid terminology has been touched upon.Razvoj plastida u subepidermi plodova varijeteta Cucurbita pepo var. pĆ¢tisson zapoÄinje sa stadijem normalno graÄenih proplastida. Sazrijevanjem ploda proplastidi prelaze u odrasle bezbojne plastide ā leukoplaste, Äija fina graÄa odgovara onoj globularnog tipa kromoplasta. Starenjem ploda u leukoplastima se razgrade sve membranske tvorevine i dolazi do potpune dezintegracije plastida. Istaknute su teÅ”koÄe terminologije u tom sluÄaju
Kromoplasti kod vrste Forsythia suspensa (Thunb.) Vahl. ā I. Fina graÄa i sastav pigmenata
The ultrastructure and pigment composition of chromoplasts in petals of Forsythia suspensa were investigated at different stages of development. The buds contained chloroplasts. During the flowering period thylakoids disappeared and numerous tubules and plastoglobules were formed. The tubules, arranged in bundles, were heterogeneous in shape and size. The plastoglobules encircled the characteristic āvacuole-likeā inclusions. The tubules and plastoglobules were probably the pigment-bearing structures of chromoplasts. The changes of pigment composition were investigated during the flower development.Istražene su promjene u finoj graÄi kromoplasta iz latica vrste Forsythia suspensa u razliÄitim stadijima razvitka. Istovremeno su praÄeni sastav i koliÄina pigmenata. Latice pupa sadržavaju tipiÄne kloroplaste. Tijekom procesa razvoja cvijeta dolazi do razgradnje tilakoida i formiranja kromoplasta s mnogobrojnim tubulima i plastoglobulima. Tubuli, koji su nepravilnog oblika, složeni su u snopiÄe. Plastoglobuli okružuju karakteristiÄne Ā»vakuolama sliÄneĀ« uklopine. Pigmenti kromoplasta vjerojatno se nalaze u tubulima i plastoglobulima
Promjene u finoj graÄi plastida tijekom žuÄenja ploda vrste Cucurbita pepo var. pyriformis
The transformation of chloroplasts to chromoplasts in the green part of the fruit of Cucurbita pepo var. pyriformis was investigated at the ultrastructural level during the process of yellowing. Two main patterns of thylakoid disintegration have been found.
1. The thylakoidal-system disintegrated and numerous plastoglobules are formed.
2. Grana-thylakoids and stroma-thylakoids gradually disappear and are transformed at the same time into long bundles of thylakoids, tubular complexes and long single thylakoids. Later on these thylakoidal-struc- tures form closely packed bundles of thylakoids. Finally all these structures disintegrate with simultaneous appearance of a great number of plastoglobules.
In both cases the final result of the thylakoid-disintegration is exactly the same, namely chromoplasts of a globular type.PraÄene su promjene u finoj graÄi plastida tijekom procesa žuÄenja zelenog dijela ploda vrste Cucurbita pepo var. pyriformis. NaÄena su dva osnovna tipa razgradnje tilakoidnoga sistema.
1. Tilakoidni sistem plastida direktno se razgraÄuje i formiraju se brojni plastoglobuli.
2. Grana-tilakoidi i stroma-tilakoidi postupno se razgraÄuju uz istovremeno formiranje novih struktura u obliku dugih snopova tilakoiÄa (koji se tijekom procesa žuÄenja ploda postupno meÄusobno sljepljuju), klupka tubula i dugih pojedinaÄnih tilakoiÄa. Na kraju se sve ove strukture razgrade i formira se veliki broj plastoglobula.
U oba sluÄaja razviju se kao konaÄni rezultat kromplasti globularnog tipa
āDuboka leksikografijaā ā pomodnost ili prilika?
In recent years, we are witnessing staggering improvements in various semantic data processing tasks due to the developments in the area of deep learning, ranging from image and video processing to speech processing, and natural language understanding. In this paper, we discuss the opportunities and challenges that these developments pose for the area of electronic lexicography. We primarily focus on the concept of representation learning of the basic elements of language, namely words, and the applicability of these word representations to lexicography. We first discuss well-known approaches to learning static representations of words, the so-called word embeddings, and their usage in lexicography-related tasks such as semantic shift detection, and cross-lingual prediction of lexical features such as concreteness and imageability. We wrap up the paper with the most recent developments in the area of word representation learning in form of learning dynamic, context-aware representations of words, showcasing some dynamic word embedding examples, and discussing improvements on lexicography-relevant tasks of word sense disambiguation and word sense induction.Posljednjih smo godina svjedoci velikoga napretka u razliÄitim zadatcima inteligentne obrade podataka koji je posljedica razvoja dubokoga uÄenja. ti zadatci ukljuÄuju i obradu slike, videa, govora te razumijevanje jezika. u ovome se radu raspravlja o prilikama i izazovima koje taj napredak omoguÄuje u podruÄju digitalne leksikografije.
VeÄi se dio rada odnosi na uÄenje prikaza razliÄitih elemenata jezika ā rijeÄi, leksema te izjava ā i njihovu primjenu u leksikografiji. Prikazuju se dobro poznati postupci uÄenja statiÄkih vektorskih prikaza rijeÄi te njihova primjena u zadatcima poput prepoznavanja semantiÄkih pomaka te predviÄanja leksiÄkih znaÄajka rijeÄi. U radu se dalje govori o viÅ”ejeziÄnoj razini uÄenja prikaza rijeÄi te se rad zakljuÄuje prikazom novijih postignuÄa u podruÄju strojnoga razumijevanja jezika ā dinamiÄkih, kontekstnih prikaza rijeÄi
Strukturne ii funkcionalne promjene plastida tijekom žuÄenja i ozelenjavanja plodova limuna
Photosynthetic activity, pigment content and fine structure of plastids in the rind of the lemon fruits have been studied. Lemon fruits very regularly change their colour through seasons ā from green into yellow and into green again.
Photosynthetic activity has been detected only in young green and regreened fruits. In yellow fruits, although they contained small amounts of chlorophylls, phyotosynthetic activity was unmeasurable. The electron microscopic examination has shown that the changing of colour of fruits is the result of a typical transformation of chloroplasts into globular chromoplasts and vice versa.plastiÄa u kori plodova limuna. Plodovi limuna pravilno mijenjaju boju tijekom godiÅ”njih doba ā od zelene u žutu i ponovno u zelenu. Fotosintetska aktivnost naÄena je u mladom zelenom plodu i u ozelenjelom plodu. U žutim plodovima, iako sadržavaju manje koliÄine klorofila,
fotosinteza nije dokazana. Elektronsko-mikroskopska istraživanja pokazuju da su promjene u boji plodova rezultat tipiÄne pretvorbe kloroplasta u kromoplaste i obrnuto
Fitoferitin u plastidima listova kupine
Crystalline inclusions of phytoferritin particles occur within the stroma of mesophyll plastids of senescing blackberry leaves (Rubus fruticosus L. s. 1.). The regreening of the senescing leaves is correlated with the disappearance of these phytoferritin inclusions.
The origin and function of phytoferritin particles in plastids, especially during the process of regreening of blackberry plastids, are discussed.U ostarjelim listovima kupine (Rubus fruticosus L. s. 1.) u plastidima mezofila nalaze se nakupine fitoferitina. Ozelenjavanje ostarjelih listova uzrokuje nestajanje fitoferitinskih uklopina iz strome plastida.
Diskutirani su porijeklo i uloga fitoferitina u plastidima kupine, posebno tijekom procesa ozelenjavanja listova
Nakupine fitoferitina u kromoplastima plodova vrste Sorbus aucuparia L.
U kromoplastima zrelih plodova vrste Sorbus aucuparia L. naÄene su velike nakupine fitoferitinskih Äestica. Kloroplasti nezrelih zelenih plodova sadrže ih samo u rijetkim i izuzetnim sluÄajevima. Autor raspravlja o porijeklu i ulozi fitoferitina u plastidima, napose u kromoplastima
Identifikacija virusnog izolata iz vrste Tropaeolum majus L.
An isolate (TK) from a virus-infected Tropaeolum majus specimen found on the island of Korcula (Jugoslavia) was investigated for purpose of identification. The virus was identified as an isolate of turnip mosaic virus (TuMV) on the basis on the following results:
Isolate TK caused only local lesions in N. tabacum cvs. āWhite Burleyā and āXanthiā-nc and C. quinoa, local lesions and sporadic systemic symptoms in C. amar anticolor, as well as systemic symptoms in N. glutinosa and B. rapa var. rapa. Infected N. glutinosa and B. rapa var. rapa plants contained elongated flexuous particles with an average length of 728 nm. Isolate TK gave a positive serological reaction with the antiserum to TuMV. It provoked the building of cytoplasmic inclusion bodies composed of a great number of needle-shaped crystals which are characteristic of TuMV. Thermal inactivation point of isolate TK was between 52Ā° and 54Ā° C. Isolate TK may belong to the ordinary strain of TuMV. This is the first finding of TuMV in a non-cruciferous species in Jugoslavia.
Infective sap of N. glutinosa contained occasionally tubular structures of submicroscopic dimensions.
The paper contains literature data on occurrence of TuMV in non- cruciferous plants, on spontaneous infections of T. majus with viruses, and data on the viruses which have been experimentally transmitted to T. majus.Istraživanja, koja smo iznijeli u ovom radu, vrÅ”ena su na virusnom izolatu (TK) iz vrste Tropaeolum majus radi njegove identifikacije. Spontano inficirani primjerak T. majus potjecao je iz Jugoslavije (Vela Luka, otok KorÄula). Na listovima prirodno inficirane biljke bili su uoÄljivi jako Å”arenilo, mozaik i deformacije. Na temelju istraživanja utvrdili smo da izolat TK predstavlja virus mozaika postrne repe (TuMV). To su, Äini se, ujedno prvi podaci o nalazu TuMV u Jugoslaviji na biljci izvan porodice krstaÅ”ica.
Rad predstavlja rijetku, ako ne i jedinu, identifikaciju TuMV iz vrste T. majus, koja osim simptoma na pokusnim biljkama (N. tabacum, N. glutinosa, C. amar anticolor, C. quinoa, B. rapa var. rapa) uzima u obzir i rezultate seroloŔkih, elektronskomikroskopskih i drugih istraživanja.
Zanimljivo je da smo u soku inficirane N. glutinosa mogli ponekad opaziti cjevaste strukture submikroskopskih dimenzija koje se mogu dovesti u vezu s virusnom infekcijom.
U radu je iznesen veÄi broj podataka iz literature o prirodnoj raÅ”irenosti TuMV na biljkama iz viÅ”e biljnih porodica, o virusima koji su prirodno raÅ”ireni na vrsti T. majus, te o virusima koji su na tu vrstu preneseni eksperimentalno
DinamiÄke promjene plastidnih nukleoida u divljeg-tipa i aurea-tipa listova kaline (Ligustrum ovalifolium Hassk. var. aureurn)
The changes in number, size, distribution and DNA content of plastid nucleoids in wild- and mutant-type leaves of an aurea variety of privet (Ligustrum ovalifolium. Hassk. var. aureum) were studied. Wild-type leaves did not show changes (in nucleoid number, size and distribution)! induced by different light intensities. Mutant leaves responded to changes in light conditions by changes in colour. During yellowing of regreened aurea leaves and bleaching of yellow aurea leaves the number of plastid nucleoids decreased with concomitant increase of their volume in such a fashion that the total volume of nucleoids and the DNA content per plastid remained constant. No degradation of chlo- roplast DNA before and during yellowing and bleaching of the aurea leaves was observed.Istraživali smo promjene broja, veliÄine, razmjeÅ”taja i sadržaja DNA, plastidnih nukleoida u divljih i mutiranih listova kaline (Ligustrum ovalifolium Hassk. var. aureum). Listovi divljeg tipa ne pokazuju promjene (broja, veliÄine i razmjeÅ”taja nukleoida) uzrokovane razliÄitim intenzitetima svjetlosti. Mutirani listovi mijenjaju boju s obzirom na intenzitet osvijetljenosti. Tijekom žuÄenja ozelenjelih listova i izbljeÄivanja žutih listova aurea, broj nukleoida se smanjuje s istovremenim poveÄanjem njihova volumena. Stoga, ukupni volumen nukleoida, a time i koliÄina DNA, ostaju konstantni u svim fazama. Razgradnja kloroplastne DNA prije i tijekom žuÄenja i izbljeÄivanja nije opažena
- ā¦