scholarly journals The evolutionary genetics of adaptation: a simulation study

1999 ◽  
Vol 74 (3) ◽  
pp. 207-214 ◽  
Author(s):  
H. ALLEN ORR
Keyword(s):  
Geometric Model ◽  
Experimental Studies ◽  
Evolutionary Genetics ◽  
Exponential Distributions ◽  
Phenotypic Effect ◽  
Gene Effects ◽  
Number Of Factors ◽  
Number Of Genes ◽  
History Of ◽  
Genetics Of Adaptation

It is now clear that the genetic basis of adaptation does not resemble that assumed by the infinitesimal model. Instead, adaptation often involves a modest number of factors of large effect and a greater number of factors of smaller effect. After reviewing relevant experimental studies, I consider recent theoretical attempts to predict the genetic architecture of adaptation from first principles. In particular, I review the history of work on Fisher's geometric model of adaptation, including recent studies which suggest that adaptation should be characterized by exponential distributions of gene effects. I also present the results of new simulation studies that test the robustness of this finding. I explore the effects of changes in the distribution of mutational effects (absolute versus relative) as well as in the nature of the character studied (total phenotypic effect versus single characters). The results show that adaptation towards a fixed optimum is generally characterized by an exponential effects trend.The situation to which these studies point is not one of a large number of genes all with more or less equal effect. It seems, rather, that a small number of genes with large effects are responsible for most of the response, the remainder of the response being due to a larger number of loci with small effects.D. S. Falconer (1981)

Beérkezett könyvek

2005 ◽  
Vol 60 (3) ◽  
pp. 425-427
Author(s):  
Csaba Pléh
Keyword(s):  
Social Interaction ◽  
Cognitive Science ◽  
Evolutionary Psychology ◽  
Well Being ◽  
General Intelligence ◽  
Human Thought ◽  
Number Of Genes ◽  
History Of ◽  
Origin Of Mind ◽  
The Mind

Ádám György: A rejtozködo elme. Egy fiziológus széljegyzetei Carpendale, J. I. M. és Müller, U. (eds): Social interaction and the development of knowledge Cloninger, R. C.: Feeling good. The science of well being Dunbar, Robin, Barrett, Louise, Lycett, John: Evolutionary psychology Dunbar, Robin: The human story. A new history of makind's evolution Geary, D. C.: The origin of mind. Evolution of brain, cognition and general intelligence Gedeon Péter, Pál Eszter, Sárkány Mihály, Somlai Péter: Az evolúció elméletei és metaforái a társadalomtudományokban Harré, Rom: Cognitive science: A philosophical introduction Horváth György: Pedagógiai pszichológia Marcus, G.: The birth of the mind. How a tiny number of genes creates the complexities of human thought Solso, R. D.: The psychology of art and the evolution of the conscious brain Wray, A. (ed.): The transition to language

scholarly journals X-chromosomal STR based genetic polymorphisms and demographic history of Sri Lankan ethnicities and their relationship with global populations

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nandika Perera ◽  
Gayani Galhena ◽  
Gaya Ranawaka
Keyword(s):  
Allele Frequency ◽  
Demographic History ◽  
Evolutionary Genetics ◽  
Haplotype Frequency ◽  
Allele Frequency Distribution ◽  
Sri Lankan ◽  
Frequency Distributions ◽  
Autosomal Str ◽  
History Of ◽  
Multiplex System

AbstractA new 16 X-short tandem repeat (STR) multiplex PCR system has recently been developed for Sr Lankans, though its applicability in evolutionary genetics and forensic investigations has not been thoroughly assessed. In this study, 838 unrelated individuals covering all four major ethnic groups (Sinhalese, Sri Lankan Tamils, Indian Tamils and Moors) in Sri Lanka were successfully genotyped using this new multiplex system. The results indicated a high forensic efficiency for the tested loci in all four ethnicities confirming its suitability for forensic applications of Sri Lankans. Allele frequency distribution of Indian Tamils showed subtle but statistically significant differences from those of Sinhalese and Moors, in contrast to frequency distributions previously reported for autosomal STR alleles. This suggest a sex biased demographic history among Sri Lankans requiring a separate X-STR allele frequency database for Indian Tamils. Substantial differences observed in the patterns of LD among the four groups demand the use of a separate haplotype frequency databases for each individual ethnicity. When analysed together with other 14 world populations, all Sri Lankan ethnicities except Indian Tamils clustered closely with populations from Indian Bhil tribe, Bangladesh and Europe reflecting their shared Indo-Aryan ancestry.

A review on phytochemical and therapeutic potential of Iris germanica

2021 ◽  
Author(s):  
Bahareh Sadat Yousefsani ◽  
Motahareh Boozari ◽  
Kobra Shirani ◽  
Amirhossein Jamshidi ◽  
Majid Dadmehr
Keyword(s):  
Bioactive Compounds ◽  
Therapeutic Potential ◽  
Experimental Studies ◽  
Therapeutic Effects ◽  
Pharmacological Activities ◽  
Pharmacological Studies ◽  
Iris Germanica ◽  
Safety Studies ◽  
History Of ◽  
Therapeutic Activities

Abstract Objectives Iris germanica L. is a medicinal plant, which has a long history of uses, mainly in medieval Persia and many places worldwide for the management of a wide variety of diseases. In this study, we aimed to review ethnopharmacological applications in addition to phytochemical and pharmacological properties of I. germanica. Key findings Ethnomedical uses of I. germanica have been reported from many countries such as China, Pakistan, India, Iran and Turkey. The medicinal part of I. germanica is the rhizome and the roots. Based on phytochemical investigations, different bioactive compounds, including flavonoids, triterpenes, sterols, phenolics, ceramides and benzoquinones, have been identified in its medicinal parts. Current pharmacological studies represent that the plant possesses several biological and therapeutic effects, including neuroprotective, hypoglycaemic, hypolipidaemic, antimicrobial, antioxidant, antiproliferative, anti-inflammatory, antiplasmodial, antifungal, immunomodulatory, cytotoxic and antimutagenic effects. Summary Although the majority of preclinical studies reported various pharmacological activities of this plant, however, sufficient clinical trials are not currently available. Therefore, to draw a definitive conclusion about the efficacy and therapeutic activities of I. germanica and its bioactive compounds, further clinical and experimental studies are required. Moreover, it is necessary to focus on the pharmacokinetic and safety studies on the extracts of I. germanica.

PERTURBATION OF SCIENTIFIC SPECIALTIES IN LAW AND THE PLACE OF BUSINESS LAW IN THE NEW SYSTEM

2021 ◽  
Vol 3 (3) ◽  
pp. 196-213
Author(s):  
I.V. Ershova
Keyword(s):  
Business Law ◽  
New Paradigm ◽  
Sociological Study ◽  
Russian Science ◽  
Scientific Organizations ◽  
Number Of Factors ◽  
Scientific Specialty ◽  
History Of ◽  
Historical Methods ◽  
New System

Introduction: attention to the problems of scientific specialties is explained by a number of factors of a substantive and formal-institutional nature. The predicted change in the nomenclature of scientific specialties, including law, makes the research topical. Purpose: to identify the consequences and evaluate the results of future changes with extrapolation of conclusions to the science of business law. Methods: analysis, synthesis, comparison, historicism, description, interpretation, forecasting, as well as sociological and historical methods. Results: an excursion into the history of the issue is made: the pre-revolutionary, Soviet and post-Soviet periods are covered. Based on the actual data, it is shown that permanent changes in the system of scientific specialties in law are a tradition of Russian science. At the same time, the previously mentioned changes were of an evolutionary nature. The current situation with dissertation research within the current nomenclature is highlighted. Factors of popularity of the scientific specialty 12.00.03 are revealed, among which-stability, successful arrangement of branches, demand for scientists. The conclusion about the correctness of preserving business law within the same specialty with civil law is confirmed. Essential and bureaucratic problems of the scientific specialty 12.00.07 are shown. The article presents the data of a sociological study, the results of which indicate divergence and progressive autarky in the field of social Sciences. The characteristics of the main expected changes in the nomenclature of scientific specialties in law, including such as consolidation, rejection of the industry criterion in the formation are given. A forecast is made about the consequences of the introduction of these innovations. The author’s opinion is expressed regarding the place of business law in the new system of scientific specialties. Attention is drawn to possible problems and a way to overcome them is suggested. Conclusions: the new paradigm of scientific specialties in law should be evaluated positively. Its application allows us to approach the interdisciplinarity, complexity of scientific research, and the creation of dissertations as integral projects. In addition to the content side, the new nomenclature is designed to minimize problems in the formation of dissertation councils, selection of candidates for official opponents, and scientific organizations.

scholarly journals Discovery and Further Studies on Giant Viruses at the IHU Mediterranee Infection That Modified the Perception of the Virosphere

Viruses ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 312 ◽  
Author(s):  
Clara Rolland ◽  
Julien Andreani ◽  
Amina Louazani ◽  
Sarah Aherfi ◽  
Rania Francis ◽  
...  
Keyword(s):  
University Hospital ◽  
Defense System ◽  
Genomic Complexity ◽  
Number Of Genes ◽  
History Of ◽  
Giant Viruses ◽  
The University ◽  
Acanthamoeba Polyphaga Mimivirus ◽  
Active Contribution

The history of giant viruses began in 2003 with the identification of Acanthamoeba polyphaga mimivirus. Since then, giant viruses of amoeba enlightened an unknown part of the viral world, and every discovery and characterization of a new giant virus modifies our perception of the virosphere. This notably includes their exceptional virion sizes from 200 nm to 2 µm and their genomic complexity with length, number of genes, and functions such as translational components never seen before. Even more surprising, Mimivirus possesses a unique mobilome composed of virophages, transpovirons, and a defense system against virophages named Mimivirus virophage resistance element (MIMIVIRE). From the discovery and isolation of new giant viruses to their possible roles in humans, this review shows the active contribution of the University Hospital Institute (IHU) Mediterranee Infection to the growing knowledge of the giant viruses’ field.

scholarly journals Renowned scientist, pedagogue, and physician Dedicated to the memory of the 110th anniversary of Bronius Sidaravičius’s birth

Medicina ◽  
2007 ◽  
Vol 43 (9) ◽  
pp. 679
Author(s):  
Gryta Laurynaitytė ◽  
Asta Lignugarienė ◽  
Skaidra Valiukevičienė
Keyword(s):  
Skin Diseases ◽  
Experimental Studies ◽  
Primary Sources ◽  
Venereal Diseases ◽  
Skin Allergy ◽  
Allergic Skin ◽  
Control And Prevention ◽  
History Of ◽  
State Archives ◽  
The University

This year we celebrate the 110th anniversary of Bronius Sidaravičius’s (1897–1969) birth. He was a renowned Lithuanian dermato-venereologist, professor, head of the Department of Skin and Venereal Diseases at Vytautas Magnus University (1935–1946, 1956–1969), the founder and the chair of the Lithuanian Society of Dermato-venereologists, coeditor of the prewar journal “Medicina.” He is an author of more than 100 articles and the very first course book on dermato-venereology in Lithuanian. He completed a part of his medical studies at universities in Germany. In Vienna University (1930), B. Sidaravičius performed clinical and experimental studies on the passive transmission of skin allergy, which had a major impact on the diagnostics of allergic skin diseases and specific desensibilization. He published the results of his study in the foreign literature and in the doctoral dissertation “Skin allergy and its treatment” in 1931. Thanks to the efforts of B. Sidaravičius and his colleagues, a progressive Law on Control and Prevention of Venereal Diseases was enacted in Lithuania. According to this Law, examinations and treatment of venereal diseases became compulsory and free of charge at state- or municipality-financed venereal outpatient units. This article was prepared on the basis of primary sources: protocols of the Council (the Faculty of Medicine, the University of Lithuania; since 1930 – Vytautas Magnus University) kept at the Museum of the History of Lithuania Medicine and Pharmacy as well as documents preserved at the Lithuanian State Archives and also scientific journals and periodicals both in Lithuanian and foreign languages.

scholarly journals Sparse coding in striate and extrastriate visual cortex

2011 ◽  
Vol 105 (6) ◽  
pp. 2907-2919 ◽  
Author(s):  
Ben D. B. Willmore ◽  
James A. Mazer ◽  
Jack L. Gallant
Keyword(s):  
Visual Cortex ◽  
Action Potentials ◽  
Experimental Studies ◽  
Natural Images ◽  
Theoretical Studies ◽  
Exponential Distributions ◽  
Neural Codes ◽  
Firing Rates ◽  
Visual Hierarchy ◽  
Primate Visual Cortex

Theoretical studies of mammalian cortex argue that efficient neural codes should be sparse. However, theoretical and experimental studies have used different definitions of the term “sparse” leading to three assumptions about the nature of sparse codes. First, codes that have high lifetime sparseness require few action potentials. Second, lifetime-sparse codes are also population-sparse. Third, neural codes are optimized to maximize lifetime sparseness. Here, we examine these assumptions in detail and test their validity in primate visual cortex. We show that lifetime and population sparseness are not necessarily correlated and that a code may have high lifetime sparseness regardless of how many action potentials it uses. We measure lifetime sparseness during presentation of natural images in three areas of macaque visual cortex, V1, V2, and V4. We find that lifetime sparseness does not increase across the visual hierarchy. This suggests that the neural code is not simply optimized to maximize lifetime sparseness. We also find that firing rates during a challenging visual task are higher than theoretical values based on metabolic limits and that responses in V1, V2, and V4 are well-described by exponential distributions. These findings are consistent with the hypothesis that neurons are optimized to maximize information transmission subject to metabolic constraints on mean firing rate.

scholarly journals Life History of the Golden Puddle Frog, Phrynobatrachus auritus Boulenger 1900 (Anura: Phrynobatrachidae)

2016 ◽  
Vol 8 (3) ◽  
pp. 77
Author(s):  
Geraud Canis Tasse Taboue ◽  
Eric Bertrand Fokam
Keyword(s):  
Life History ◽  
Development Time ◽  
Captive Breeding ◽  
Sub Saharan Africa ◽  
Advertisement Call ◽  
Calling Behaviour ◽  
Number Of Factors ◽  
History Of ◽  
Sub Saharan

Frogs of the genus <em>Phrynobatrachus </em>Günther, 1862 are endemic to sub-Saharan Africa. These are increasingly threatened by a number of factors and are believed to be declining. We report on captive breeding experiments involving <em>Phrynobatrachus auritus</em> Boulenger, 1900. We provide a comprehensive life history for this frog with emphasize on tadpole development time, as well as a description of both the advertisement call and calling behaviour of the adult.

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