scholarly journals Comparative study of the vegetative and generative organs in pear varieties

2006 ◽  
Vol 12 (3) ◽  
Author(s):  
P. Dremák ◽  
G. Kocsisné Molnár
Keyword(s):  
Comparative Study ◽  
Relative Frequency ◽  
Main Axis ◽  
Point Of View ◽  
Lateral Branches ◽  
Generative Organs

An assortment of 17 pear varieties was examined in 2006 at Keszthely, Department of Horticulture, Georgicon Faculty of Agriculture, Veszprem University. The selected varieties were planted in 1980, grafted on seedling rootstock and represented the majority of existing pear plantations in Hungary. The main objective was the determination of suitability of the most important varieties for the purpose of intensive growing technologies even when grafted on vigorous seedling rootstock. The most important growing and fruiting characteristics of the varieties have been assessed and evaluated from the point of view of productivity. We stated that the relations of the trunk or the main axis to the lateral branches and fruiting structures are all subject to varietal effects and are valuable indices of the growing character. The quotient of the diameters of trunk and branch should be around 0.3-0.4, and the relative frequency of fruiting structures (Dárda, nyárs, vessző) meaning the ability of branching and regeneration associated with accurate pruning policies are decisive from the point of view of promising success.

scholarly journals The effect of cadmium on growth of vegetative thallus and development of generative organs of Chara vulgaris L. after short time of cultivation

2014 ◽  
Vol 66 (1) ◽  
pp. 67-72 ◽  
Author(s):  
Aleksandra Gosek ◽  
Maria Kwiatkowska ◽  
Robert Duszyński
Keyword(s):  
Main Axis ◽  
Cadmium Ions ◽  
Chara Vulgaris ◽  
Lateral Branches ◽  
Short Time ◽  
Number Of Cells ◽  
Generative Organs

The effect of cadmium ions in two different concentrations (10<sup>-8</sup>M i 10<sup>-6</sup>M) on vegetative thallus, male (antheridia) and femele (oogonia) generative organs of <em>Chara vulgaris</em> L. was investigated. After 9 days of growth in a presence of cadmium the number of lateral branches decreased and the lengths of internodes of the main axis and pleuridia became shortened. The increase in oospores volume and decrease in antheridial volume (both total and internal) after 3, 7 and 9 days of cultivation were observed. The productivity of antheridium measured by the number of antheridial filaments and number of cells within filament is also lower in plants cultivated with cadmium in comparison with control ones.

scholarly journals Effect of GA3, IAA and their mixtures on the formation and development of cell systems in the vegetative and generative thallus of Chara vulgaris L.

2014 ◽  
Vol 60 (3-4) ◽  
pp. 313-326 ◽  
Author(s):  
Maria Kwiatkowska ◽  
Aleksandra Gosek ◽  
Mirosław Godlewski
Keyword(s):  
Inhibitory Effect ◽  
Main Axis ◽  
Stimulatory Action ◽  
Cell Systems ◽  
Low Concentration ◽  
Chara Vulgaris ◽  
Vegetative Part ◽  
Lateral Branches ◽  
High Level ◽  
Generative Organs

In concentrations ranging from 10<sup>-7</sup> to 10<sup>-5</sup> M IAA strongly stimulates the growth of the main axis and pleuridia internodal cells, while it does not affect the number of lateral branches and generative organs. In the higher concentrations it reduces the number of spermatozoids in the antheridium. In the same concentration range, GA<sub>3</sub>, inhibits the growth of the main axis and pleuridia internodal cells, does not affect the number of lateral branches, increases the number of antheridia and increases the number of forming spermatozoids. Incubation in mixture of both regulators has shown that: a) IAA eliminates the inhibitory effect of GA<sub>3</sub> on the growth of internodal cells of the main axis and its stimulatory action is slightly weakened by GA<sub>3</sub>, b) IAA in a concentration of 10<sup>-5</sup> M along with a low concentration of GA<sub>3</sub>, (10<sup>-7</sup>) increases the number of main axis lateral branches. The conclusion is drawn that the growth of the vegetative part of the thallus is more intense when auxin predominates, but generative development requires a high level of gibberellin.

Determination of Pyridostigmine Bromide in Presence of its Related Impurities by Four Modified Classical Least Square Based Models: A Comparative Study

2020 ◽  
Vol 17 (1) ◽  
pp. 87-94
Author(s):  
Ibrahim A. Naguib ◽  
Fatma F. Abdallah ◽  
Aml A. Emam ◽  
Eglal A. Abdelaleem
Keyword(s):  
Comparative Study ◽  
Least Squares ◽  
Orthogonal Projection ◽  
Predictive Ability ◽  
Least Square ◽  
Projection To Latent Structures ◽  
Preprocessing Method ◽  
Spectral Residual ◽  
Latent Structures

: Quantitative determination of pyridostigmine bromide in the presence of its two related substances; impurity A and impurity B was considered as a case study to construct the comparison. Introduction: Novel manipulations of the well-known classical least squares multivariate calibration model were explained in detail as a comparative analytical study in this research work. In addition to the application of plain classical least squares model, two preprocessing steps were tried, where prior to modeling with classical least squares, first derivatization and orthogonal projection to latent structures were applied to produce two novel manipulations of the classical least square-based model. Moreover, spectral residual augmented classical least squares model is included in the present comparative study. Methods: 3 factor 4 level design was implemented constructing a training set of 16 mixtures with different concentrations of the studied components. To investigate the predictive ability of the studied models; a test set consisting of 9 mixtures was constructed. Results: The key performance indicator of this comparative study was the root mean square error of prediction for the independent test set mixtures, where it was found 1.367 when classical least squares applied with no preprocessing method, 1.352 when first derivative data was implemented, 0.2100 when orthogonal projection to latent structures preprocessing method was applied and 0.2747 when spectral residual augmented classical least squares was performed. Conclusion: Coupling of classical least squares model with orthogonal projection to latent structures preprocessing method produced significant improvement of the predictive ability of it.

scholarly journals Evaluation of the Ability to Accurately Produce Angular Details by 3D Printing of Plastic Parts

Machines ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 150
Author(s):  
Andrei Marius Mihalache ◽  
Gheorghe Nagîț ◽  
Laurențiu Slătineanu ◽  
Adelina Hrițuc ◽  
Angelos Markopoulos ◽  
...  
Keyword(s):  
3D Printing ◽  
Point Of View ◽  
Vertex Angle ◽  
Function Type ◽  
Constant Height ◽  
3D Printers ◽  
3D Printed ◽  
Mathematical Processing ◽  
Plastic Parts

3D printing is a process that has become widely used in recent years, allowing the production of parts with relatively complicated shapes from metallic and non-metallic materials. In some cases, it is challenging to evaluate the ability of 3D printers to make fine details of parts. For such an assessment, the printing of samples showing intersections of surfaces with low angle values was considered. An experimental plan was designed and materialized to highlight the influence of different factors, such as the thickness of the deposited material layer, the printing speed, the cooling and filling conditions of the 3D-printed part, and the thickness of the sample. Samples using areas in the form of isosceles triangles with constant height or bases with the same length, respectively, were used. The mathematical processing of the experimental results allowed the determination of empirical mathematical models of the power-function type. It allowed the detection of both the direction of actions and the intensity of the influence exerted by the input factors. It is concluded that the strongest influence on the printer’s ability to produce fine detail, from the point of view addressed in the paper, is exerted by the vertex angle, whose reduction leads to a decrease in printing accuracy.

scholarly journals Influence of the socio-economic environment on the entrepreneurs behavior. Cases of cuba and ecuador

2021 ◽  
Vol 13 ◽  
pp. 184797902199450
Author(s):  
Reyner Pérez-Campdesuñer ◽  
Gelmar García-Vidal ◽  
Alexander Sánchez-Rodríguez ◽  
Rodobaldo Martínez-Vivar ◽  
Margarita de Miguel-Guzmán ◽  
...  
Keyword(s):  
Comparative Study ◽  
Point Of View ◽  
Personality Characteristics ◽  
Social Model ◽  
Historical Evolution ◽  
Government Regulations ◽  
Failure Risk ◽  
Short And Long Term ◽  
Financial Environment

Entrepreneurship is an important part of any economy today regardless of its level of development. However, not in all contexts do entrepreneurs operate in the same way, nor are they motivated by the same factors. This research seeks to identify possible coincidence factors and differences between entrepreneurs that operate in different contexts from the point of view of their historical evolution, the duration of these and the economic and social model applied in the countries. Specifically, a comparative study is carried out between entrepreneurs from the republics of Ecuador and Cuba considering various variables such as: personality characteristics (attitude to failure, risk, perseverance and innovation), use of the available time fund for work in entrepreneurship; Impact of the environment in relation to: government regulations, taxes, level of competition and availability of suppliers, as well as the structure of personal expenses projected in the short and long term that entrepreneurs assume as a stimulus for their actions. For the development of the study, a description of the behavior of the variables was initially made and later, by hypothesis testing, to verify differences and similarities between both populations. The study allowed us to identify common and divergent aspects between both populations analyzed. Similarly, it showed how differences in the administrative and financial environment in which entrepreneurs operate generate changes in their priorities and projections.

Determination of a Rubber-Like Material Model as an Inverse Problem

2011 ◽  
Vol 70 ◽  
pp. 225-230 ◽  
Author(s):  
Agnieszka Derewonko ◽  
Andrzej Kiczko
Keyword(s):  
Selection Process ◽  
Axial Stress ◽  
Constitutive Models ◽  
Material Model ◽  
Polyester Fabric ◽  
Point Of View ◽  
Air Cushion ◽  
Ill Conditioning ◽  
Stress States

The purpose of this paper is to describe the selection process of a rubber-like material model useful for simulation behaviour of an inflatable air cushion under multi-axial stress states. The air cushion is a part of a single segment of a pontoon bridge. The air cushion is constructed of a polyester fabric reinforced membrane such as Hypalon®. From a numerical point of view such a composite type poses a challenge since numerical ill-conditioning can occur due to stiffness differences between rubber and fabric. Due to the analysis of the large deformation dynamic response of the structure, the LS-Dyna code is used. Since LS-Dyna contains more than two-hundred constitutive models the inverse method is used to determine parameters characterizing the material on the base of results of the experimental test.

scholarly journals Comparative study of two immunoassays used for the determination of serum vitamin D

2021 ◽  
pp. e00242
Author(s):  
Raquel Lahoz ◽  
Juan Pelegrín Sánchez ◽  
Silvia Górriz ◽  
Pilar Calmarza
Keyword(s):  
Vitamin D ◽  
Comparative Study ◽  
Serum Vitamin ◽  
Serum Vitamin D

Resistance to Outflow of Cerebrospinal Fluid Determined by Bolus Injection Technique and Constant Rate Steady State Infusion in Humans

Neurosurgery ◽  
1985 ◽  
Vol 16 (3) ◽  
pp. 336-340 ◽  
Author(s):  
Michael Kosteljanetz
Keyword(s):  
Cerebrospinal Fluid ◽  
Steady State ◽  
Bolus Injection ◽  
Point Of View ◽  
Injection Technique ◽  
Communicating Hydrocephalus ◽  
Constant Rate ◽  
High Degree ◽  
Infusion Technique

Abstract Two methods for the determination of resistance to the outflow of cerebrospinal fluid, the bolus injection technique and the constant rate steady state infusion technique, were compared. Thirty-two patients with a variety of intracranial diseases (usually communicating hydrocephalus) were studied. There was a high degree of correlation between the resistance values obtained with the two methods, but values based on the bolus injection technique were systematically and statistically significantly lower than those obtained with the constant rate infusion test. From a practical point of view. both methods were found to be applicable in a clinical setting.

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