FURTHER STUDIES ON INDUCED APOGAMY IN FERNS

1962 ◽  
Vol 40 (11) ◽  
pp. 1525-1531 ◽  
Author(s):  
D. P. Whittier ◽  
T. A. Steeves
Keyword(s):  
Carbohydrate Metabolism ◽  
Osmotic Potential ◽  
Culture Medium ◽  
General Applicability ◽  
Sterile Culture ◽  
The One ◽  
Induced Apogamy ◽  
Fern Gametophytes

Apogamous sporophyte formation has been induced in 14 strains of seven species of normal fern gametophytes using a technique similar to the one reported earlier (Whittier and Steeves, Can. J. Bot. 38, 925–930 (1960)). These gametophytes were supplied with suitable concentrations of sugar in the sterile culture medium for certain lengths of time which resulted in the formation of apogamous sporophytes. This investigation demonstrated that sucrose is more effective in inducing apogamy probably because it produces about half the osmotic potential as an equivalent percentage of glucose. Therefore more sugar can be made available to gametophytes before the osmotic potential deleteriously affects the prothallial growth and apogamy. This confirms the work carried out previously using sugar in the medium and it demonstrates that this method has general applicability for inducing apogamy in ferns. The sugar in the medium is felt to modify the carbohydrate metabolism enabling the prothalli to undergo a thickened growth and develop apogamous sporophytes.

scholarly journals Modes of Interaction in Naturally Occurring Medical Encounters With General Practitioners: The “One in a Million” Study

2021 ◽  
pp. 104973232199379
Author(s):  
Olaug S. Lian ◽  
Sarah Nettleton ◽  
Åge Wifstad ◽  
Christopher Dowrick
Keyword(s):  
General Practitioners ◽  
Narrative Analysis ◽  
Mode Competition ◽  
General Applicability ◽  
Naturally Occurring ◽  
Wide Range ◽  
The One ◽  
Narrative Mode ◽  
Modes Of Interaction

In this article, we qualitatively explore the manner and style in which medical encounters between patients and general practitioners (GPs) are mutually conducted, as exhibited in situ in 10 consultations sourced from the One in a Million: Primary Care Consultations Archive in England. Our main objectives are to identify interactional modes, to develop a classification of these modes, and to uncover how modes emerge and shift both within and between consultations. Deploying an interactional perspective and a thematic and narrative analysis of consultation transcripts, we identified five distinctive interactional modes: question and answer (Q&A) mode, lecture mode, probabilistic mode, competition mode, and narrative mode. Most modes are GP-led. Mode shifts within consultations generally map on to the chronology of the medical encounter. Patient-led narrative modes are initiated by patients themselves, which demonstrates agency. Our classification of modes derives from complete naturally occurring consultations, covering a wide range of symptoms, and may have general applicability.

Many-body Green functions in nuclear physics

2017 ◽  
Vol 26 (01n02) ◽  
pp. 1740025 ◽  
Author(s):  
J. Speth ◽  
N. Lyutorovich
Keyword(s):  
Nuclear Physics ◽  
Green Functions ◽  
Many Body ◽  
General Applicability ◽  
Pair Correlations ◽  
Self Consistent ◽  
The Many ◽  
The One ◽  
General Relations ◽  
Three Body

Many-body Green functions are a very efficient formulation of the many-body problem. We review the application of this method to nuclear physics problems. The formulas which can be derived are of general applicability, e.g., in self-consistent as well as in nonself-consistent calculations. With the help of the Landau renormalization, one obtains relations without any approximations. This allows to apply conservation laws which lead to important general relations. We investigate the one-body and two-body Green functions as well as the three-body Green function and discuss their connection to nuclear observables. The generalization to systems with pair correlations are also presented. Numerical examples are compared with experimental data.

The Use of Legal Expert Systems in Administrative Decision Making

2011 ◽  
pp. 151-169
Author(s):  
Jorgen S. Svensson
Keyword(s):  
Expert Systems ◽  
Professional Status ◽  
General Applicability ◽  
National Regulation ◽  
General Assistance ◽  
Legal Expert ◽  
Social Scientific ◽  
The One ◽  
State Programs ◽  
Legal Expert Systems

The chapter will now start with a short introduction into the Dutch General Assistance Act, its administration and the problems concerned with that administration. Then, I will discuss the idea of expert systems support and present the results of several investigations into the application of expert systems, in this context. Given these results, some have been quick to argue that expert systems are indeed important and valuable tools in the administration of welfare state programs. The next section will present important arguments against too much optimism. Both from a legal scientific as well as from a social scientific perspective, objections against the use of expert systems have been formulated. On the one hand, these objections have to be taken seriously, because they clearly have some validity, and thus require attention when discussing the possibilities of expert systems. On the other, it is important to notice that these objections have not prevented the introduction of these systems in general assistance in the Netherlands. As I will then explain, the fact that expert systems are now accepted by the General Assistance administrations, has to do with several specific factors, which really have promoted the use of expert systems in this field. Factors that have to do with the specific role of national regulation, with the professional status of the bureaucrats and with the increased scrutiny under which the administrations now have to function. In the last section of this chapter, I will draw some conclusions with respect to the general applicability of legal expert systems in service provision and provide some arguments for the idea that expert systems will soon become an important technology in electronic service delivery.

On Sequential Sampling for Global Metamodeling in Engineering Design

2002 ◽  
Author(s):  
Ruichen Jin ◽  
Wei Chen ◽  
Agus Sudjianto
Keyword(s):  
Complex Systems ◽  
Engineering Design ◽  
Sequential Sampling ◽  
Test Problems ◽  
Sampling Strategies ◽  
General Applicability ◽  
One Stage ◽  
Computationally Expensive ◽  
The One ◽  
Global Metamodeling

Approximation models (also known as metamodels) have been widely used in engineering design to facilitate analysis and optimization of complex systems that involve computationally expensive simulation programs. The accuracy of metamodels is directly related to the sampling strategies used. Our goal in this paper is to investigate the general applicability of sequential sampling for creating global metamodels. Various sequential sampling approaches are reviewed and new approaches are proposed. The performances of these approaches are investigated against that of the one-stage approach using a set of test problems with a variety of features. The potential usages of sequential sampling strategies are also discussed.

Aminimides. II. A one-step synthesis of aminimides from carboxylic acid esters

1967 ◽  
Vol 45 (21) ◽  
pp. 2619-2623 ◽  
Author(s):  
William J. McKillip ◽  
Robert C. Slagel
Keyword(s):  
Carboxylic Acid ◽  
Reaction Temperature ◽  
Sodium Methoxide ◽  
General Applicability ◽  
Acyl Substituent ◽  
One Step ◽  
The One ◽  
Substituent Influence ◽  
Acid Esters

The general applicability of preparing aminimides from esters and insitu generated 1,1,1-trimethylaminimine is reported. Acyclic, alicyclic, aromatic, and heteroaromatic trimethylaminimides have been synthesized by the one-step reaction. The synthetic scheme consists of reacting an ester with a 1,1,1-trimethylhydrazinium salt in the presence of an anhydrous base such as sodium methoxide. The choice of solvent, reaction temperature, and base and the electronegativity of the acyl substituent influence the ease of aminimide formation.

scholarly journals Fungi colonizing various organs of thyme Thymus vulgaris L. cultivated in the region of Lublin

2013 ◽  
Vol 55 (1) ◽  
pp. 185-197
Author(s):  
Zofia Machowicz-Stefaniak ◽  
Beata Zimowska ◽  
Ewa Zalewska
Keyword(s):  
Culture Medium ◽  
Pathogenic Fungi ◽  
Malt Agar ◽  
Thymus Vulgaris ◽  
Thielaviopsis Basicola ◽  
Fusarium Spp ◽  
Disease Symptoms ◽  
Second Year ◽  
One Year ◽  
The One

In 1998-2001, the healthiness of thyme cultivated in the region of Lublin was examined. Surveys were made on the one-year-old plantations of thyme at a stage of 6-week-old seedlings and just before the first harvest of the crop, as well as on the two-year-old plantations in spring and before the last harvest. The percentage of the plants showing fungal disease symptoms and the index of infection with fungi were determined. The fungi were isolated from superficially disinfected plant fragments namely from roots, bases of stem and leaves, separately, using mineral culture medium. PDA and SNA media were used to culture <i>Fusarium</i> spp., malt-agar and Czapek-Dox ones to culture <i>Penicillium</i> spp. and malt-agar, oat-agar and cherry-agar ones to culture <i>Phoma</i> spp. The percentage of plant infected with the fungi ranged within 12.18 and 23.05, in case of the one-year-old plantations, and within 29.91 and 43.65 in the two-year-old ones, whereas values of the index of infection ranged within 11.56 and 24.69 and within 20.75 and 43,28, respectively. Necroses were observed on roots and base of stems on one-year-old and two-year-old plantations, but in the last period of vegetation of thyme close to harvest. very often stems and leaves showed symptoms of a complete necrosis. It was found that base of stems and roots of thyme in the first and the second year of cultivation were colonized by a complex of pathogenic fungi:<i>Fusarium spp., Rhizoctonia solani, Thielaviopsis basicola</i> were obtained from the major part of diseased plants. Among the <i>Fusarium</i> species colonizing bases of stems <i>F.culmorum, F.avenaceum, F.equiseti</i> and <i>F.oxysporum</i> dominated, but from roots of thyme most often <i>F.oxysporum, F.equiseti and F.culmorum</i> were isolated. From stems, and particularly from leaves of thyme showing dark spots, commonly <i>Alternaria alternata</i> was obtained. On the other hand, shoots and leaves, but rarely roots of thyme, were colonized by various species of <i>Phoma</i>, particularly by <i>Phoma exigua</i> var. <i>exigua. Colletotrichum gleosporioides</i> occurred rarely on thyme in the area surveyed.

scholarly journals Electrochemomechanical Behavior of Polypyrrole-Coated Nanofiber Scaffolds in Cell Culture Medium

Polymers ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1043 ◽  
Author(s):  
Madis Harjo ◽  
Janno Torop ◽  
Martin Järvekülg ◽  
Tarmo Tamm ◽  
Rudolf Kiefer
Keyword(s):  
Cell Culture ◽  
Culture Medium ◽  
Surprising Result ◽  
Cell Culture Medium ◽  
X Ray ◽  
Nanofiber Scaffolds ◽  
Na Ions ◽  
Fiber Scaffolds ◽  
The One ◽  
Deposition Conditions

Glucose-gelatin nanofiber scaffolds were made conductive and electroactive by chemical (conductive fiber scaffolds, CFS) and additionally electrochemical polypyrrole deposition (doped with triflouromethanesulfonate CF3SO3−, CFS-PPyTF). Both materials were investigated in their linear actuation properties in cell culture medium (CCM), as they could be potential electro-mechanically activated cell growth substrates. Independent of the deposition conditions, both materials showed relatively stable cation-driven actuation in CCM, based on the flux of mainly Na+ ions from CCM. The surprising result was attributed to re-doping by sulfate anions in CCM, as also indicated by energy-dispersive X-ray (EDX) spectroscopy results. Overall, the electrochemically coated material outperformed the one with just chemical coating in conductivity, charge density and actuation response.

Digital images coupled to PLS regression for pH prediction in sterile culture medium

2022 ◽  
Vol 73 ◽  
pp. 103435
Author(s):  
Ânderson Ramos Carvalho ◽  
Luana Candice Genz Bazana ◽  
Alexandre Meneghello Fuentefria ◽  
Marco Flôres Ferrão
Keyword(s):  
Culture Medium ◽  
Digital Images ◽  
Pls Regression ◽  
Sterile Culture

INDUCED APOGAMY IN DIPLOID GAMETOPHYTES OF PTERIDIUM

1966 ◽  
Vol 44 (12) ◽  
pp. 1717-1721 ◽  
Author(s):  
D. P. Whittier
Keyword(s):  
Weight Basis ◽  
Sterile Culture ◽  
Self Fertilization ◽  
Induced Apogamy

Diploid gametophytes were produced via self-fertilization and apospory from a strain of haploid gametophytes which underwent apogamy in sterile culture. These diploid gametophytes of the fern, Pteridium, demonstrated quantitative differences from the haploid prothalli. The diameters of the rhizoids and antheridia were larger on the diploid prothalli. The diploid gametophytes grew slightly faster than the haploids. Under conditions which induced apogamy in the haploid prothalli, the diploids produced more apogamous sporophytes on a culture or on a weight basis than did the haploid prothalli.

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