Probit analysis is a type of regression used to analyze the relationship between a stimulus and the quantal response. Allelopathy refers to direct or indirect negative or positive effects of one plant on another through the release of chemical compounds into the environment. This study was carried out to apply probit analysis in investigating the allelopathic effects of the leaves aqueous extracts of apple of Sodom [Calotropis procera (Aiton) W.T.] on the inhibition of seed germination of African rattlebox (Crotalaria saltiana Andr.). A laboratory experiments were carried out at the Faculty of Agricultural Sciences, University of Gezira, Sudan in season 2014/15. Ten concentrations (2.3, 4.6, 7.0, 9.3, 11.6, 13.9, 16.2, 18.5, 20.8 and 23.2 g/l) leaves aqueous extract of apple of Sodom were prepared from the stock solution (50 g / l). A control with sterilized-distilled water was included for comparison. Treatments were arranged in completely randomized design with four replicates. The seeds were examined for inhibition (%) in germination at three days after initial germination. Collected data were transformed using Abbott’s formula and subjected to probit analysis procedure (P £ 0.5). The results showed that the leaves aqueous extract of apple of Sadom had allelopathic effects on seed germination of African rattlebox and there was direct positive relationship between concentration (g/l) and inhibition (%). Also, the data indicated that plotting of corrected inhibition (%) against concentration (%) formed a sigmoid curve. Probit analysis transformed the sigmoid concentration-response curve to a straight line. Hence, the LC25 (2.16 g/l), LC50 (8.55 g/l) and LC75 (33.88 g/l) were accurately estimated. It was concluded that probit analysis is appropriate procedure in studying the allelopathy phenomenon.
Copula modeling is widely used in modern statistics. The boundary bias problem is one of the problems faced when estimating by nonparametric methods, as kernel estimators are the most common in nonparametric estimation. In this paper, the copula density function was estimated using the probit transformation nonparametric method in order to get rid of the boundary bias problem that the kernel estimators suffer from. Using simulation for three nonparametric methods to estimate the copula density function and we proposed a new method that is better than the rest of the methods by five types of copulas with different sample sizes and different levels of correlation between the copula variables and the different parameters for the function. The
... Show MoreIn this work, an experimental analysis is made to predict the thermal performance of the natural-convection phenomenon from a heated vertical externally finned-tube to surrounding air through an open-ended enclosure. Two different configurations of longitudinal rectangular fin namely, continuous and interrupted are utilized with constant thickness, different numbers, and different heights are extended radially on the outer surface of a heated tube. The tube is heated electrically from inner surface with five varied power input magnitudes. The effect of fins configuration, fins number, fins height, and heat flux of the inner tube surface on the thermal performance of natural c
... Show MoreThe modern nation state, by virtue of its institutional nature, is divided into political and non-political institutions according to their respective jurisdictions. It is natural for non-political institutions to perform their functions under the control of the political establishment, for two reasons: first, Second: Ensuring the achievement of cooperation, harmony and integration between these different institutions in serving the stability of the society and its continuity and achieving its supreme objectives. The location of the military establishment is part of the non-political institutions of the state, since it carries out a non-political function that is based on defending the homeland against any threats that may threaten its s
... Show Morethe contemporary Arab scholars deal with semiotics as an approach that helps them understand the texts, its meaning, and its structural functionalism . that’s why every now and then we find some
studies and researches using semiotics as an approach in study and comparatives, some of them even used the semiotic approach in analyzing old and new texts, while others think that semiotic holds and important place in critical approaches .
even though some of them considers semiotic just a trend of fashion this really didn’t lessen the value of semiotic as a scientific and procedural approach in literary and media studies as well as in analyzing literary and journalistic texts. for this reason it is considered as an important approa
The presence of the "calcite eyes" is related to an internal physiological reason rather than genetically reason or parasite inhabitation. The individual of this family tries to create open spaces in the areas of its body intensively crowded by the main partition or its branches to avoid oxygen scarcity (dysoxic condition). This mechanism keeps the living matter in touch each to the other as well as continuity of the animal life. After death and burial, these created spaces are filled with pure calcite, as it is the case in the chamber passage. This phenomenon took place in both megalospheric and microspheric generations.
Coronavirus disease (Covid-19) has threatened human life, so it has become necessary to study this disease from many aspects. This study aims to identify the nature of the effect of interdependence between these countries and the impact of each other on each other by designating these countries as heads for the proposed graph and measuring the distance between them using the ultrametric spanning tree. In this paper, a network of countries in the Middle East is described using the tools of graph theory.
The Phenomenon of Euphemism in the Translon Activity Euphemism is the replacement of a harsh word with a less harsh or more acceptable one. Most languages are affected by ideological, cultural, social, or religious perspectives which in turn would reflect different linguistic levels. On such a basis, translation is affected by its medium,i.e. language, and consequently what is acceptably expressed by a nation may not be acceptable by another. In this paper, we try to
... Show MoreThe phenomenon of negative behavior has studied as a social and psychological phenomenon that effect on the performance and life of workers inside and outside the organization. The adoption of this phenomenon is studied in terms of the role of the internal environment of the organization in addressing this behavior, being the variables belong to the field of organizational behavior to see the results of those variables on the Iraqi organizations, since the specificities of it differ from the rest of the Arab and foreign environments. Therefore, this study focused on testing the relationship of the internal environment of the organization and its role in addressing the negative behavior of the workers.
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... Show MoreCluster analysis (clustering) is mainly concerned with dividing a number of data elements into clusters. The paper applies this method to create a gathering of symmetrical government agencies with the aim to classify them and understand how far they are close to each other in terms of administrative and financial corruption by means of five variables representing the prevalent administrative and financial corruption in the state institutions. Cluster analysis has been applied to each of these variables to understand the extent to which these agencies are close to other in each of the cases related to the administrative and financial corruption.