scholarly journals Localization of Thallium in Stomata is Independent of Transpiration

1972 ◽  
Vol 25 (2) ◽  
pp. 415 ◽  
Author(s):  
CK Pallaghy
Keyword(s):  
Guard Cells ◽  
Recent Interest ◽  
The Subject ◽  
Subsidiary Cells

The specific locations of the evaporating surfaces in the leaf are not yet known. However, Maercker (1965) repeated successfully the early experiments of Stahl (1894) and concluded from her evidence that the cuticular component oftranspiration could be further divided into "cuticular" and "peristomatal" transpiration, where the latter term refers to transpiration from the surfaces of the guard cells and their subsidiary cells. Peristomatal transpiration has been the subject of considerable recent interest (e.g. Lange et al. 1971).

A Scanning Electron Microscope Study of Isolated Guard Cells

1973 ◽  
Vol 31 ◽  
pp. 454-455 ◽  
Author(s):  
P. Dayanandan ◽  
P. B. Kaufman
Keyword(s):  
Electron Microscope ◽  
Electron Microscope Study ◽  
Three Dimensional ◽  
Guard Cells ◽  
Scanning Electron Microscope Study ◽  
Psilotum Nudum ◽  
Subsidiary Cells ◽  
Welwitschia Mirabilis ◽  
Cycas Revoluta ◽  
Scanning Electron

A three dimensional appreciation of the guard cell morphology coupled with ultrastjuctural studies should lead to a better understanding of their still obscure dynamics of movement. We have found the SEM of great value not only in studies of the surface details of stomata but also in resolving the structures and relationships that exist between the guard and subsidiary cells. We now report the isolation and SEM studies of guard cells from nine genera of plants.Guard cells were isolated from the following plants: Psilotum nudum, four species of Equisetum, Cycas revoluta, Ceratozamia sp., Pinus sylvestris, Ephedra cochuma, Welwitschia mirabilis, Euphorbia tirucalli and Allium cepa.

ONTOGENY OF STOMATA IN SOME CRUCIFERAE

1967 ◽  
Vol 45 (4) ◽  
pp. 495-500 ◽  
Author(s):  
G. S. Paliwal
Keyword(s):  
Guard Cells ◽  
Vertical Division ◽  
Subsidiary Cells

The ontogeny of stomata was investigated in 12 species of Cruciferae. The three subsidiary cells as well as the guard cells originate from the same protodermal cell and thus the ontogeny conforms to the syndetocheilic type. The mature stomata are anisocytic. Sometimes, the subsidiary cells undergo a transverse and (or) vertical division and the mature stoma shows four to five subsidiary cells.

Fossil flowers and leaves of the Ebenaceae from the Eocene of southern Australia

1985 ◽  
Vol 63 (10) ◽  
pp. 1825-1843 ◽  
Author(s):  
James F. Basinger ◽  
David C. Christophel
Keyword(s):  
Guard Cells ◽  
Epidermal Cells ◽  
Fossil Leaves ◽  
Extant Species ◽  
Late Tertiary ◽  
The Family ◽  
Fossil Flowers ◽  
Subsidiary Cells ◽  
Clay Lenses ◽  
Coal Measures

Numerous flowers and a diverse assemblage of leaves are mummified in clay lenses in the base of the Demons Bluff Formation overlying the Eastern View Coal Measures. Fossil localities occur in the Alcoa of Australia open cut near Anglesea, Victoria, Australia. Flowers are tubular, less than 10 mm long, and about 5 mm wide. Four sepals are connate forming a cup-shaped calyx. Four petals are fused in their basal third and alternate with sepals. Flowers are all unisexual and staminate. Stamens are epipetalous and consistently 16 in number, arranged in 8 radial pairs. Pollen is subprolate, tricolporate, and about 32 μm in diameter. The exine is smooth to slightly scabrate. A rudimentary ovary occurs in some flowers. Sepals usually have a somewhat textureless abaxial cuticle with actinocytic stomata. Some sepals, however, have frill-like cuticular thickenings over some abaxial epidermal cells and some subsidiary cells with pronounced papillae overarching guard cells. One of the more common leaf types found associated with the flowers is characterized by the same peculiar cuticular thickenings and overarching papillae on subsidiary cells that occur on sepals. This cuticular similarity indicates that flowers and leaves represent a single taxon. Leaves are highly variable in size and shape but are consistently entire margined, with pinnate, brochidodromous venation. The suite of features characterizing the flowers is unique to the Ebenaceae. Flowers of many extant species of Diospyros (Ebenaceae) closely resemble the fossil flowers. Fossil leaves, too, are typical of leaves of extant Diospyros. Both flowers and leaves are considered conspecific and have been assigned the name Austrodiospyros cryptostoma gen. et sp. nov. The Anglesea fossils represent one of the earliest well-documented occurrences of the Ebenaceae and are the earliest known remains of Ebenaceae from Australia. They support the hypothesis of a Gondwanan origin for the family with late Tertiary diversification in the Malesian region.

Non-Cepheids in the Instability Strip

1985 ◽  
Vol 82 ◽  
pp. 83-83 ◽  
Author(s):  
William P. Bidelman
Keyword(s):  
High Luminosity ◽  
Complete Sample ◽  
Instability Strip ◽  
Considerable Uncertainty ◽  
Recent Interest ◽  
The Subject

AbstractThe question of whether non-Cepheids populate the cepheid instability strip has been the subject of much recent interest. Several investigators (see especially Fernie and Hube 1971 and Fernie 1976) have concluded that indeed there are an appreciable number of objects not presently recognized as Cepheids within the strip, though both the size and position of the strip and the placement of supergiants in the H-R diagram are subject to considerable uncertainty. In view of the interest in this matter, I have attempted to shed some light on this situation by simply considering the nature of the stars spectroscopically classified as of high luminosity in spectral classes F and G. For this one needs, of course, a complete sample of the relevant stars, which fortunately is now to some extent available.

Growth of High Nitrogen Content GaAsN by Metalorganic Chemical Vapor Deposition

2001 ◽  
Vol 692 ◽  
Author(s):  
J. C. Roberts ◽  
B. F. Moody ◽  
P. Barletta ◽  
M. E. Aumer ◽  
S. F. LeBoeuf ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Metalorganic Chemical Vapor Deposition ◽  
Nitrogen Concentration ◽  
Chemical Vapor ◽  
High Nitrogen Content ◽  
Recent Interest ◽  
The Subject ◽  
Lattice Matched ◽  
Metalorganic Chemical

AbstractThe incorporation of a high percentage of nitrogen in the GaAs lattice has been the subject of recent interest to reduce the bandgap while maintaining the nearly lattice matched condition to GaAs. We will report on the metalorganic chemical vapor deposition (MOCVD) of GaAsN using trimethylgallium (TMG), tertiarybutylarsine (TBA) and dimethylhydrazine (DMHy) organometallic sources in a hydrogen-free carrier gas. A nitrogen concentration as high as ∼8% in GaAsN was achieved. The effect of nitrogen concentration on the structural, optical and surface properties of GaAsN films will be discussed.

scholarly journals Development of stomata in Hordeum vulgare L. under the influence of oleander glycosides and colchicine

2015 ◽  
Vol 44 (4) ◽  
pp. 637-647 ◽  
Author(s):  
J. A. Tarkowska ◽  
M. Wierzbicka ◽  
M. Grzegrzółka
Keyword(s):  
Hordeum Vulgare ◽  
Aqueous Solutions ◽  
Growth Inhibition ◽  
Phase Ii ◽  
Guard Cells ◽  
Similar Type ◽  
Hordeum Vulgare L ◽  
Cell Divisions ◽  
Subsidiary Cells ◽  
Growth Of Seedlings

The effect of aqueous solutions of a 0.1 per cent mixture of oleander glycosides and of 0.1 and 0.5 per cent colchicine on the growth of seedlings, and particularly on the development of stomata was investigated in <i>Hordeum vulgare</i> L. The compounds were found not to penetrate with the same readiness through the coleoptile: glycosides passed very slowly, while colchicine rapidly. Growth inhibition of seedlings increased with the concentrations of the solutions applied, the time of incubation and the degree of damage to the coleoptile. Colchicine and glycosides cause a similar type of disturbances in all cell divisions leading to the formation of stomata. Most numerous disturbances were noted in phase II. The cause of these disorders lies in damage to the karyokinetic sipindle and abnormal cytokinesis. As a result are formed the stomata with a changed number of guard cells or subsidiary cells, their shape is changed and sometimes also their orientation and the dimensions are reduced.

scholarly journals Micromorphology of glandular structures in Echium vulgare L. flowers

2012 ◽  
Vol 61 (2) ◽  
pp. 25-34 ◽  
Author(s):  
Elżbieta Weryszko-Chmielewska ◽  
Mirosława Chwil
Keyword(s):  
Glandular Trichomes ◽  
Guard Cells ◽  
Epidermal Cells ◽  
Lower Region ◽  
Small Column ◽  
Anomocytic Stomata ◽  
Cuticular Ornamentation ◽  
Glandular Cells ◽  
Subsidiary Cells ◽  
Glandular Structures

The micromorphology of selected elements of <i>Echium vulgare</i> L. flowers was investigated, with special attention to the structure of the nectaries and the stigma of the pistil as well as types of trichomes occurring on the surface of the calyx. The nectary had the shape of an uneven disc located around the lower region of the four-parted ovary of the pistil. The glandular cells formed a tier with a height of 330 μm and a radial width of 144 μm. Nectar was secreted onto the nectary surface through anomocytic stomata located at the level of other epidermal cells. Most of the stomata were open, with a different dimension of the pore. Their largest number was observed at the base of the nectary, and 462 stomata were noted on the whole surface of the nectary. The cuticle on the surface of the guard cells formed fine, circular striae. The subsidiary cells formed striated cuticular ornamentation, with the striae arranged radially in the direction of the stoma, whereas on the surface of other epidermal cells the striae formed an arrangement with different directions. The epidermis on the surface of the stigma formed regularly arranged papillae with a fan-shaped, expanded upper part which had corrugated outer walls, whereas the base of the cell formed a widened small column. The epidermis of the abaxial part of the calyx was covered by numerous non-glandular trichomes of different length which were made up of one or several cells. The glandular trichomes in the epidermis of the calyx grew with smaller density compared to the protective trichomes, and they were composed of a 1-2-celled stalk and a glandular head.

scholarly journals Rozwój i stan krajobrazu językowego – przypadek języka wilamowskiego

Adeptus ◽  
2019 ◽  
Author(s):  
Justyna Majerska-Sznajder
Keyword(s):  
Cultural Landscape ◽  
Western Europe ◽  
Linguistic Landscape ◽  
Grass Roots ◽  
The Past ◽  
Current State ◽  
Recent Interest ◽  
The Subject ◽  
Recent Activity ◽  
Grass Roots Initiatives

The development and current state of the linguistic landscape – the case of the Wymysorys languageWymysorys is a micro-language with Germanic roots spoken by the residents of Wilamowice, a small Silesian town located between Oświęcim and Bielsko-Biała, where it was brought by settlers from Western Europe in the thirteenth century. It has been the subject of scholarly interest among specialists in a number of fields, not only linguistics and ethnology, since the early twentieth century. Following a ban issued by local authorities in 1945, the use of Wymysorys was prohibited and public manifestations of local culture were severely punished. This policy resulted in a drastic decline of the number of its users. The recent interest of researchers is focused not only on the documentation of Wymysorys or its sociolinguistic situation in the past and today, but also on the effects of its revitalization in the last decade. Despite the lack of institutional support, the users’ community has been engaged in grass-roots initiatives leading to the emergence of Wymysorys in the cultural landscape. Recent activity of its users indicates that the language has already spread beyond the circles of local activists and, after years of persecution, functions again in society, evolving and taking new forms. Rozwój i stan krajobrazu językowego – przypadek języka wilamowskiegoJęzyk wilamowski, którym posługują się mieszkańcy Wilamowic (wym. Wymysoü), od początku XX wieku interesuje naukowców wielu dziedzin – nie tylko lingwistów i etnologów. Został on przywieziony przez osadników z Europy Zachodniej w XIII wieku na teren obecnych Wilamowic – małego miasteczka na Śląsku leżącego między Oświęcimiem a Bielskiem-Białą. Na skutek zakazu wydanego przez władze lokalne w 1945 roku używanie wilamowskiego było zabronione, a wszelkie publiczne przejawy odmiennej kultury ostro karane, w związku z czym liczba użytkowników wilamowskiego zaczęła drastycznie maleć. Zainteresowanie badaczy ostatnimi czasy wzbudza nie tylko kwestia dokumentacji tego mikrojęzyka o germańskich korzeniach czy stan etnolingwistyczny. Obserwacji podlegają również obecne efekty zaaplikowanych w ostatniej dekadzie procesów rewitalizacji językowej i zmiany lokalnej, a także państwowej polityki językowej. Mimo braku instytucjonalnego wsparcia, społeczeństwo użytkowników oddolnie podejmuje inicjatywy, których efektem jest między innymi pojawianie się wilamowskiego w krajobrazie kulturowym. Ostatnie działania użytkowników języka świadczą o tym, że opuścił już kręgi lokalnych aktywistów i ponownie, po latach zakazu, funkcjonuje samodzielnie w społeczeństwie, ewoluując i przybierając nowe formy.

Robotic System based on Computational Intelligence - Evolutionary Generation of Regrasping Motion

2000 ◽  
Vol 4 (6) ◽  
pp. 437-442
Author(s):  
Toshio Fukuda ◽  
◽  
Yasuhisa Hasegawa ◽  
Keyword(s):  
Numerical Simulation ◽  
Computational Intelligence ◽  
Evolutionary Programming ◽  
Robot Hand ◽  
Optimal Solutions ◽  
Recent Interest ◽  
Robot Hands ◽  
Grasping Force ◽  
Real Robot ◽  
The Subject

The control of multifingered robot hands has been the subject of recent interest. To regrasp an object, there are many parameters to be determined; grasping points, grasping force, regrasping phases, finger allocation and so on. It is difficult to optimize such manipulation parameters for achieving effective manipulation. In this section, we propose generation of regrasping motion for a four-fingered robot hand using Evolutionary Programming (EP). Evolutionary optimization is generally able to find optimal solutions without supervisor after much iteration, which makes it almost impractical to apply a real robot directly. Therefore, we apply the controller in numerical simulation to the real robot hand. We show effectiveness of the propose method for the regrasping motion with experimental results.

Anterior Cingulectomy in Schizophrenia and Other Psychotic Disorders: Clinical Results

1954 ◽  
Vol 100 (418) ◽  
pp. 46-61 ◽  
Author(s):  
P. Macdonald Tow ◽  
R. W. Armstrong
Keyword(s):  
Mental Disorders ◽  
Local Anaesthesia ◽  
Psychotic Disorders ◽  
Clinical Results ◽  
Recent Interest ◽  
Mental Change ◽  
Original Procedure ◽  
The Subject ◽  
Constant Observation ◽  
Small Bundle

Recent interest in the surgical alleviation of mental disorders has centred in the trial of new and different operations. Fairly early in the development of the subject Freeman and Watts (1944) themselves reported the fairly constant observation that under local anaesthesia gross mental change did not occur until certain stab incisions had been made deep in the infero-medial quadrants. Marked mental change, with confusion, unresponsiveness and disorientation, seemed to occur on section of a small bundle of fibres located interiorly close to the midline. Most of the modifications of Moniz's original procedure have, however, been made on an essentially empirical basis.

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