scholarly journals Genetic and Biochemical Characterization Underpinning the Development of Floral Features that Influence Pollination – A Review

2021 ◽  
Vol 18 (2) ◽  
pp. 251-261
Author(s):  
S. Venkatesan Venkatesan ◽  
P. Masilamani Masilamani ◽  
P. Janaki ◽  
T. Eevera ◽  
S. Sundareswaran Sundareswaran ◽  
...  

In the process of sexual reproduction in angiosperms, making viable pollen grain to land on the surface of the receptive stigma of the same flower or other flower is the key process. Major factors like both biotic and abiotic play a crucial role in the process of making pollen to reach stigma during sexual mode of reproduction in angiosperms. In nature, some of the plants pollination take place without the support of any of the above said two factors, in some of the cases transfer of pollen aided by the biotic factors viz., insects, birds, animals etc., Particularly in the process of insect or bird aided pollen transfer, secretion of volatile compound in view of attracting pollinators have multiple role. In addition to above, flower with variety of colour also play a huge role in attraction of pollinators and its aid in timely occurrence of pollination. Further, due to climate change some of the pollinator population also become extinct, under that condition through evolutionary changes plant change their phenotypic expression by that way they attract other group of pollinator in the process of sexual mode of reproduction. Only the plant able to change their adaptation through the evolutionary process or through the event of mutation based on their requirement alone able to survive. This review discusses some of the important strategy adopted by the flowering plants in view of attraction of pollinators.

Author(s):  
Bryan G. Levman

Abstract This article continues the discussion on the nature of the early language of Buddhism and the language that the Buddha spoke, arguing that the received Pāli transmission evolved out of an earlier Middle Indic idiom, which is identified as a koine. Evidence for this koine can be found by examining correspondence sets within Pāli and its various varieties and by examining parallel, cognate correspondence sets between Pāli and other Prakrits which have survived. This article compares 30 correspondence sets transmitted in the Dhammapada recensions: the Gāndhārī Prakrit verses, the partially Sanskritized Pāli and Patna Dhammapada Prakrit verses, and the fully Sanskritized verses of the Udānavarga. By comparing cognate words, it demonstrates the existence of an underlying inter-language which in many cases can be shown to be the source of the phonological differences in the transmission. The paper includes a discussion on the two major factors of dialect change, evolution with variation over time, and the diffusionary, synchronic influence of dialect variation; it concludes that both are important, with dialect variation – and the phonological constraints of indigenous speakers who adopted MI as a second language – providing the pathways on which the natural evolutionary process was channeled.


2016 ◽  
Vol 19 (1) ◽  
pp. 61-70
Author(s):  
Thuan Quoc Pham ◽  
Dao Xuan La

The objective of this study is to identify the major factors that impact on the quality of financial reporting and to suggest model of the factors affecting on the quality of financial reporting for Vietnamese enterprises . There are two factors group affecting on the quality of financial reporting: internal factors and external factors, this study is limited to the scope of the external factors. By using case studies, analytical results indicate that Tax Pressure factor has the greatest impact on the quality of financial reporting, the remaning factors include: Listed Securities, Accounting Software and Independent Audit. Two factors, Politics and Regulatory Environment have limited impact on the quality financial reporting.


2017 ◽  
Vol 63 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Muchkund Dubey

The nation states have emerged and been shaped through an evolutionary process. The major factors triggering their emergence have been rise of capitalism, breakdown of empires, independence of colonial territories and, in recent years, the disintegration of large federal states. The character and the authority of nation states have been shaped initially by the interstate system of the Treaty of Westphalia and largely by the French Revolution and the United Nations (UN) Charter, rise of regionalism and globalisation. Nationalism continues to thrive and remain dominant all over the world mainly because its possible substitutes such as global capitalism, socialist internationalism and UN multilateralism did not prove viable. The major challenges the nation states face today are coping with new problems arising within their territories and those which affect the very survival of mankind. The Indian nationalism embraces the entire variety of elements which go into the making of a nation state. It has been a subject of bitter controversy starting from India’s independence movement. To be true to its ethos reflected in the Indian Constitution, it must remain pluralistic, inclusive and humanitarian.


2018 ◽  
Vol 2 (1) ◽  
pp. 18-26
Author(s):  
Wen Ji ◽  
Jing Liu ◽  
Zhiwen Pan ◽  
Jingce Xu ◽  
Bing Liang ◽  
...  

Purpose With development of machine learning techniques, the artificial intelligence systems such as crowd networks are becoming more and more autonomous and smart. Therefore, there is a growing demand to develop a universal intelligence measurement so that the intelligence of artificial intelligence systems can be evaluated. This paper aims to propose a more formalized and accurate machine intelligence measurement method. Design/methodology/approach This paper proposes a quality–time–complexity universal intelligence measurement method to measure the intelligence of agents. Findings By observing the interaction process between the agent and the environment, we abstract three major factors for intelligence measure as quality, time and complexity of environment. Practical implications In a crowd network, a number of intelligent agents are able to collaborate with each other to finish a certain kind of sophisticated tasks. The proposed approach can be used to allocate the tasks to the agents within a crowd network in an optimized manner. Originality/value This paper proposes a calculable universal intelligent measure method through considering more than two factors and the correlations between factors which are involved in an intelligent measurement.


2010 ◽  
Vol 450 ◽  
pp. 202-205 ◽  
Author(s):  
Hong Wei Ji ◽  
Huai Wen Wang

Short span compressive experiments of molded pulp specimens were carried out on the SHIMADZU material test machine, resulting in the stress-strain curves. The analytic results indicate that the material density and the loading rate are the two major factors that influence the stress-strain relationships of the molded pulp materials. With the increase of material’s density, elastic modulus and ultimate strength both increase. With the increase of loading rate, elastic modulus decreases whereas ultimate strength increases. By analyzing the test results and the existing models, an improved stress-strain model for molded pulp material, with the two factors taken into consideration, has been proposed. The model coefficients are obtained by fitting against the short span compressive experimental data for the materials with different densities under different loading rate. Comparison made between the experimental results and calculated results indicates that the proposed model can well fit the stress-strain curves of molded pulp.


2015 ◽  
Vol 29 (06) ◽  
pp. 1550033 ◽  
Author(s):  
Lili Gao ◽  
Feng Wang ◽  
Lan Jiang ◽  
Liangti Qu ◽  
Yongfeng Lu

This paper is focused on the excitation rates of free electrons of an aluminum (Al) bulk irradiated by an elliptically polarized laser in simulation, using time-dependent density functional theory (TDDFT). The polarized 400 nm, 10 fs laser pulse consisted of two elementary sinusoidal beams, and is adjusted by changing the phase difference φ and the intersection angle θ of the polarization directions between the two beams. The simulation includes cases of φ = π/2 with θ = 30°, θ = 45°, θ = 60°, θ = 90°, θ = 120°, θ = 135°, θ = 150°, and cases of θ = 90° with φ = π/4, φ = π/3, φ = π/2, φ = 2π/3, φ = 3π/4. The absorbed energy, the excitation rates and the density distributions of free electrons after laser termination are investigated. At the given power intensity (1×1014 W cm -2), pulse width (10 fs) and wavelength (400 nm) of each elementary laser beam, computational results indicate that the excitation rate of free electrons is impacted by three major factors: the long axis direction of the laser projected profile, the amplitude difference of the first main oscillation (1st AD), and the total amplitude difference of main oscillations (TAD) of the external electric field. Among the aforementioned three factors for the excitation rate of free electrons, the direction of long axis plays the most significant role. The screen effect is crucial to compare the importance of the remaining two factors. The analysis approach to investigate the electron dynamics under an elliptically polarized laser is both pioneering and effective.


2006 ◽  
Vol 20 (1) ◽  
pp. 29-44 ◽  
Author(s):  
Robert R. McCrae ◽  
Antonio Terracciano ◽  
Paul T. Costa ◽  
Daniel J. Ozer

To investigate recent hypotheses of replicable personality types, we examined data from 1540 self‐sorts on the California Adult Q‐Set (CAQ). Conventional factor analysis of the items showed the expected Five‐Factor Model (FFM). Inverse factor analysis across random subsamples showed that none of the previously reported person‐factors were replicated. Only two factors were replicable, and, most importantly, these factors were contaminated by mean level differences in item endorsement. Results were not due to sample size or age heterogeneity. Subsequent inverse factor analysis of standardized items revealed at least three replicable factors; when five person‐factors were extracted, they could be aligned precisely with the dimensions of the FFM. The major factors of person similarity can be accounted for entirely in terms of the FFM, consistent with the hypothesis that there are no replicable personality types in the CAQ. Published in 2006 John Wiley & Sons, Ltd.


2020 ◽  
Author(s):  
Thomas Scheuerl ◽  
Veijo Kaitala

AbstractAll organisms are sensitive to the abiotic environment, and in multispecies communities a deteriorating environment increasing mortality and limiting coexistence time can cause ecological changes. When interaction within the community is changed this can impact co-evolutionary processes. Here we use a mathematical model to predict ecological and evolutionary changes in a simple predator-prey community under different mortality rates and times of coexistence, both controlled by various transfer volume and transfer interval. In the simulated bacteria-ciliate system, we find species densities to be surprisingly robust under changed mortality rates and times both species coexist, resulting in stable densities. Confirming a theoretical prediction however, the evolution of anti-predator defence in the bacteria and evolution of predation efficiency in ciliates relax under high mortalities and limited times both partners interact. In contrast, evolutionary trajectories intensify when global mortalities are low, and the predator-prey community has more time for close interaction. These results provide testable hypotheses for future studies of predator-prey systems and we hope this work will help to bridge the gap in our knowledge how ecological and evolutionary process together shape composition of microbial communities.


1999 ◽  
Vol 16 (1) ◽  
pp. 150-157
Author(s):  
Dawud Abdul-Aziz Agbere

African-American Islam, especially as practiced by the Nation oflslam, continuesto engage the attention of many scholars. The racial separatist tendency,contrasted against the color blindness of global Islam, has been the focal pointof most of these studies. The historical presence of African Americans in themidst of American racism has been explained as, among other things, the mainimpetus behind African-American nationalism and racial separatism. Islam inthe African-American Experience is yet another attempt to explain this historicalposition. Originally the author's Ph.D. dissertation, the book spans 293pages, including notes, select biographies, indices, and thirteen illustrations. Itstwo parts, "Root Sources" and "Prophets of the City," comprise six chapters; there is also an introduction and an epilogue. The book is particularly designedfor students interested in African-American Islam. The central theme of thebook is the signifktion (naming and identifying) of the African Americanwithin the context of global Islam. The author identifies three factors thatexplain the racial-separatist phenomenon of African-American Islam:American racism, the Pan-African political movements of African-Americansin the early twentieth century, and the historic patterns of racial separatism inIslam. His explanations of the first two factors, though not new to the field ofAfrican-American studies, is well presented. However, his third explanation,which tries to connect the racial-separatist tendency of African-AmericanMuslims to what he tern the “historic pattern of racial separatism” in Islam,seems both controversial and problematic.In his introduction, the author touches on the African American’s sensitivityto signification, citing the long debate in African-American circles. Islam, heargues, offered African Americans two consolations: first, a spiritual, communal,and global meaning, which discoMects them in some way from Americanpolitical and public life; second, a source of political and cultural meaning inAfrican-American popular culture. He argues that a black person in America,Muslim or otherwise, takes an Islamic name to maintain or reclaim Africancultural roots or to negate the power and meaning of his European name. Thus,Islam to the black American is not just a spiritual domain, but also a culturalheritage.Part 1, “Root Sources,” contains two chapters and traces the black Africancontact with Islam from the beginning with Bilal during the time of theProphet, to the subsequent expansion of Islam to black Africa, particularlyWest Africa, by means of conversion, conquest, and trade. He also points to animportant fact: the exemplary spiritual and intellectual qualities of NorthAmerican Muslims were major factors behind black West Africans conversionto Islam. The author discusses the role of Arab Muslims in the enslavement ofAfrican Muslims under the banner of jihad, particularly in West Africa, abehavior the author described as Arabs’ separate and radical agenda for WestAfrican black Muslims. Nonetheless, the author categorically absolves Islam,as a system of religion, from the acts of its adherents (p. 21). This notwithstanding,the author notes the role these Muslims played in the educational andprofessional development of African Muslims ...


2018 ◽  
Author(s):  
Mikhail I. Katsnelson ◽  
Yuri I. Wolf ◽  
Eugene V. Koonin

One of the key tenets of Darwin’s theory that was inherited by the Modern Synthesis of evolutionary biology is gradualism, that is, the notion that evolution proceeds gradually, via accumulation of “infinitesimally small” heritable changes 1,2. However, some of the most consequential evolutionary changes, such as, for example, the emergence of major taxa, seem to occur abruptly rather than gradually, as captured in the concepts of punctuated equilibrium 3,4 and evolutionary transitions 5,6. We examine a mathematical model of an evolutionary process on a rugged fitness landscape 7,8 and obtain analytic solutions for the probability of multi-mutational leaps, that is, several mutations occurring simultaneously, within a single generation in one genome, and being fixed all together in the evolving population. The results indicate that, for typical, empirically observed combinations of the parameters of the evolutionary process, namely, effective population size, mutation rate, and distribution of selection coefficients of mutations, the probability of a multi-mutational leap is low, and accordingly, their contribution to the evolutionary process is minor at best. However, such leaps could become an important factor of evolution in situations of population bottlenecks and elevated mutation rates, such as stress-induced mutagenesis in microbes or tumor progression, as well as major evolutionary transitions and evolution of primordial replicators.


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