Flower development inPisum sativum: From the war of the whorls to the battle of the common primordia

1999 ◽  
Vol 25 (3) ◽  
pp. 280-290 ◽  
Author(s):  
C. Ferr�ndiz ◽  
C. Navarro ◽  
M.D. G�mez ◽  
L.A. Ca�as ◽  
J.P. Beltr�n
Keyword(s):  
Flower Development ◽  
The Common

Flavonol Synthase Activity and the Regulation of Flavonol and Anthocyanin Biosynthesis during Flower Development in Dianthus caryophyllus L. (Carnation)

1992 ◽  
Vol 47 (7-8) ◽  
pp. 553-560 ◽  
Author(s):  
K. Stich ◽  
T. Eidenberger ◽  
F. Wurst ◽  
G. Forkmann
Keyword(s):  
Flower Development ◽  
Anthocyanin Biosynthesis ◽  
Dianthus Caryophyllus ◽  
Anthocyanin Synthesis ◽  
Ph Optimum ◽  
Flavonol Synthase ◽  
Common Substrate ◽  
The Common ◽  
Time Courses ◽  
Maximum Expression

Flavonol synthase (FLS) was demonstrated in crude extracts from flower buds of Dianthus caryophyllus (carnation). The enzyme catalyzed the conversion of dihydrokaempferol and ihydroquercetin to kaempferol and quercetin, respectively. The reaction required 2-oxoglutarate, ferrous ion and ascorbate as co-factors and had a pH optimum at about 7.4. The demonstration of FLS activity allowed comparative studies on flavonol and anthocyanin biosynthesis during bud and flower development. Besides FLS the flavonoid enzymes chalcone synthase (CHS), flavanone 3-hydroxylase (FH T) and dihydroflavonol 4-reductase (DFR) were measured. DFR is specifically involved in anthocyanin synthesis, while CHS and FHT provide dihydroflavonol, the common substrate for both FLS and DFR . Maximum expression of CHS, FHT and FLS activity was already observed in small buds, whereas DFR activity started to increase much later and reached its highest level in opened flowers. A substantial correlation was observed between the time courses of FLS and DFR activity and the accumulation of flavonols and anthocyanins, respectively. The competition of FLS and DFR for dihydroflavonols was found to be largely circumvented by different substrate specificities and by the sequential expression of the two enzymes. Both flavonols and anthocyanins are obviously not, or only to some extent, subject to degradation.

scholarly journals Inflorescence and flower development in the Hedychieae (Zingiberaceae): Hedychium

1997 ◽  
Vol 75 (4) ◽  
pp. 581-594 ◽  
Author(s):  
Bruce K. Kirchoff
Keyword(s):  
Key Words ◽  
Flower Development ◽  
Developmental Period ◽  
Relative Timing ◽  
Flower Structure ◽  
Hedychium Coronarium ◽  
Mature Flower ◽  
The Common ◽  
Sequential Formation

Flower organogenesis in Hedychium gardnerianum and Hedychium coronarium begins with the sequential formation of the sepals on a rounded–triangular apex. Growth in three regions of the apex, inside the sepals, produces three common petal – inner androecial primordia. Intercalary growth below and between these primordia produces a floral cup, the site of gynoecial formation. The common primordia separate to form petals and inner androecial members. After separation, the anterior inner androecial members fuse to form the labellum. The posterior member forms the polleniferous stamen. Up to this point in development, the flowers of H. coronarium are slightly ahead of those of H. gardnerianum. However, in H. gardnerianum, initiation of the two thecae of the stamen occurs immediately following the separation of the common primordia, while thecae formation in H. coronarium is slightly delayed. These results show that the relative timing of developmental events can vary even over a short developmental period. Formation of the outer androecium takes place at the apices of a triangle formed by the inner androecial members. The anterior outer androecial member aborts soon after formation, whereas the posterior outer androecial members form the two petaloid staminodes that are found on the lateral sides of the labellum in the mature flower. Key words: flower development, flower structure, inflorescence, stamen, Zingiberaceae, Hedychium.

Catalogue reduction techniques

1978 ◽  
Vol 48 ◽  
pp. 389-390 ◽  
Author(s):  
Chr. de Vegt
Keyword(s):  
Adjustment Process ◽  
Proper Motions ◽  
Measuring Process ◽  
Aerial Photogrammetry ◽  
Reduction Techniques ◽  
Observational Technique ◽  
The Common ◽  
Astrometric Data

AbstractReduction techniques as applied to astrometric data material tend to split up traditionally into at least two different classes according to the observational technique used, namely transit circle observations and photographic observations. Although it is not realized fully in practice at present, the application of a blockadjustment technique for all kind of catalogue reductions is suggested. The term blockadjustment shall denote in this context the common adjustment of the principal unknowns which are the positions, proper motions and certain reduction parameters modelling the systematic properties of the observational process. Especially for old epoch catalogue data we frequently meet the situation that no independent detailed information on the telescope properties and other instrumental parameters, describing for example the measuring process, is available from special calibration observations or measurements; therefore the adjustment process should be highly self-calibrating, that means: all necessary information has to be extracted from the catalogue data themselves. Successful applications of this concept have been made already in the field of aerial photogrammetry.

Renilla Bioluminescence: A Morphologic Approach to the Location of Photocytes

1974 ◽  
Vol 32 ◽  
pp. 208-209
Author(s):  
Ben O. Spurlock ◽  
Milton J. Cormier
Keyword(s):  
Excited State ◽  
Ground State ◽  
Molecular Basis ◽  
Light Emission ◽  
Chemical Basis ◽  
Electronic Excited State ◽  
Colonial Form ◽  
The Common ◽  
Eighteenth And Nineteenth Centuries ◽  
Catalyzed Oxidation

The phenomenon of bioluminescence has fascinated layman and scientist alike for many centuries. During the eighteenth and nineteenth centuries a number of observations were reported on the physiology of bioluminescence in Renilla, the common sea pansy. More recently biochemists have directed their attention to the molecular basis of luminosity in this colonial form. These studies have centered primarily on defining the chemical basis for bioluminescence and its control. It is now established that bioluminescence in Renilla arises due to the luciferase-catalyzed oxidation of luciferin. This results in the creation of a product (oxyluciferin) in an electronic excited state. The transition of oxyluciferin from its excited state to the ground state leads to light emission.

Mammalian Bone Marrow Acetylcholinesterase

1982 ◽  
Vol 40 ◽  
pp. 44-45
Author(s):  
Ezzatollah Keyhani
Keyword(s):  
Central Nervous System ◽  
Bone Marrow ◽  
Nervous System ◽  
Common Property ◽  
Extracellular Medium ◽  
The Central Nervous System ◽  
The Common ◽  
Mammalian Bone

Acetylcholinesterase (EC 3.1.1.7) (ACHE) has been localized at cholinergic junctions both in the central nervous system and at the periphery and it functions in neurotransmission. ACHE was also found in other tissues without involvement in neurotransmission, but exhibiting the common property of transporting water and ions. This communication describes intracellular ACHE in mammalian bone marrow and its secretion into the extracellular medium.

Correlation analysis of radiation damage

1978 ◽  
Vol 36 (1) ◽  
pp. 214-215
Author(s):  
R. Hegerl ◽  
A. Feltynowski ◽  
B. Grill
Keyword(s):  
Electron Microscopy ◽  
Independent Random Variables ◽  
Optical Parameters ◽  
Bright Field Image ◽  
Bright Field ◽  
Expectation Value ◽  
All Optical ◽  
Image Element ◽  
Stochastic Series ◽  
The Common

Till now correlation functions have been used in electron microscopy for two purposes: a) to find the common origin of two micrographs representing the same object, b) to check the optical parameters e. g. the focus. There is a third possibility of application, if all optical parameters are constant during a series of exposures. In this case all differences between the micrographs can only be caused by different noise distributions and by modifications of the object induced by radiation.Because of the electron noise, a discrete bright field image can be considered as a stochastic series Pm,where i denotes the number of the image and m (m = 1,.., M) the image element. Assuming a stable object, the expectation value of Pm would be Ηm for all images. The electron noise can be introduced by addition of stationary, mutual independent random variables nm with zero expectation and the variance. It is possible to treat the modifications of the object as a noise, too.

The Red Neuronal Pigment in the Nervous System of the Mussel, Mytilus Edulis: Localization and Its Effect on Lateral Ciliary Activity with Spectral and Analytical Changes

1981 ◽  
Vol 39 ◽  
pp. 494-495
Author(s):  
Anthony A. Paparo ◽  
Judith A. Murphy
Keyword(s):  
Nervous System ◽  
Mytilus Edulis ◽  
Neuronal Cell ◽  
Ciliary Activity ◽  
Neuronal Cell Bodies ◽  
The Central Nervous System ◽  
Intracellular Organelles ◽  
The Common ◽  
The Individual ◽  
Cryostat Sections

The purpose of this study was to localize the red neuronal pigment in Mytilus edulis and examine its role in the control of lateral ciliary activity in the gill. The visceral ganglia (Vg) in the central nervous system show an over al red pigmentation. Most red pigments examined in squash preps and cryostat sec tions were localized in the neuronal cell bodies and proximal axon regions. Unstained cryostat sections showed highly localized patches of this pigment scattered throughout the cells in the form of dense granular masses about 5-7 um in diameter, with the individual granules ranging from 0.6-1.3 um in diame ter. Tissue stained with Gomori's method for Fe showed bright blue granular masses of about the same size and structure as previously seen in unstained cryostat sections.Thick section microanalysis (Fig.l) confirmed both the localization and presence of Fe in the nerve cell. These nerve cells of the Vg share with other pigmented photosensitive cells the common cytostructural feature of localization of absorbing molecules in intracellular organelles where they are tightly ordered in fine substructures.

Si(Li) detector for microanalysis cooled by thermoelectric device

1992 ◽  
Vol 50 (2) ◽  
pp. 1736-1737
Author(s):  
Shaul Barkan
Keyword(s):  
Solid State ◽  
Liquid Nitrogen ◽  
Thermoelectric Device ◽  
Peltier Cooler ◽  
Complicated Process ◽  
The Common

Cooling down solid state detecors, with other different way then liquid Nitrogen, is a goal of many vendors and customers since the invention of these detectors. THe disadvantage of the common way of liquid Nitrogen is first the inavailibility of the LN in many uses (like space military and any other applications that are not done inside a well organize Laboratory). The use of LN also considers as a Labor consumer in addition to the big dewar that has to be added to any detector for storing the LN, the boiling of the LN, may cause microphonics problesm and the refiling of the dewar in many Labs is a complicated process due to inconvenience location of the microscope.In this paper I will show a spectra result of 10mm2 SiLi detector for microanalysis use, cooled by peltier cooler. The peltier cooler has the advantage of non-microphonics and non-labor needed (like adding LN to the dewar).

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