نتایج جستجو برای: ancient

تعداد نتایج: 38123  

Journal: :J. Comput. Syst. Sci. 2007
Telikepalli Kavitha

We consider the problem of determining if two finite groups are isomorphic. The groups are assumed to be represented by their multiplication tables. We present an O(n) algorithm that determines if two Abelian groups with n elements each are isomorphic. This improves upon the previous upper bound of O(n log n) [23] known for this problem. We solve a more general problem of computing the orders o...

Journal: :Proceedings. Biological sciences 2014
Jessica L Metcalf Stefan Prost David Nogués-Bravo Eric G DeChaine Christian Anderson Persaram Batra Miguel B Araújo Alan Cooper Robert P Guralnick

One of the grand goals of historical biogeography is to understand how and why species' population sizes and distributions change over time. Multiple types of data drawn from disparate fields, combined into a single modelling framework, are necessary to document changes in a species's demography and distribution, and to determine the drivers responsible for change. Yet truly integrated approach...

Journal: :IJICTHD 2012
Christopher Wilson Alexandra Dunn

This chapter proposes an analytic approach for the study of ICTs in contentious politics and human rights advocacy. By applying the analytical frames of contingency and hybridity to study design, this approach aims to promote empirical analyses, strengthen data comparability, and improve understanding into how human rights activists strategically combine digital and grounded communications to r...

Journal: :Theoretical population biology 2016
Nicolas Duforet-Frebourg Montgomery Slatkin

With the great advances in ancient DNA extraction, genetic data are now obtained from geographically separated individuals from both present and past. However, population genetics theory about the joint effect of space and time has not been thoroughly studied. Based on the classical stepping-stone model, we develop the theory of Isolation by distance and time. We derive the correlation of allel...

2015
Melissa Dewolf Miriam Bassok Keith J. Holyoak

Previous research on multiplicative reasoning has shown that for whole numbers, understanding of division is intimately linked to multiplication, as retrieval of division facts is often accomplished through reverse multiplication. We recently extended this research to rational numbers, and found that inverse multiplication problems can serve as primes for one another (e.g., a × b/a = a primes b...

2015
Robin G. Allaby Rafal Gutaker Andrew C. Clarke Neil Pearson Roselyn Ware Sarah A. Palmer James L. Kitchen Oliver Smith

Our understanding of the evolution of domestication has changed radically in the past 10 years, from a relatively simplistic rapid origin scenario to a protracted complex process in which plants adapted to the human environment. The adaptation of plants continued as the human environment changed with the expansion of agriculture from its centres of origin. Using archaeogenomics and computationa...

Journal: :Philosophical transactions of the Royal Society of London. Series B, Biological sciences 2015
Maja Krzewińska Gro Bjørnstad Pontus Skoglund Pall Isolfur Olason Jan Bill Anders Götherström Erika Hagelberg

The medieval Norsemen or Vikings had an important biological and cultural impact on many parts of Europe through raids, colonization and trade, from about AD 793 to 1066. To help understand the genetic affinities of the ancient Norsemen, and their genetic contribution to the gene pool of other Europeans, we analysed DNA markers in Late Iron Age skeletal remains from Norway. DNA was extracted fr...

Journal: :Philosophical transactions of the Royal Society of London. Series B, Biological sciences 2015
M Parks S Subramanian C Baroni M C Salvatore G Zhang C D Millar D M Lambert

Recently, the study of ancient DNA (aDNA) has been greatly enhanced by the development of second-generation DNA sequencing technologies and targeted enrichment strategies. These developments have allowed the recovery of several complete ancient genomes, a result that would have been considered virtually impossible only a decade ago. Prior to these developments, aDNA research was largely focused...

Journal: :Molecular ecology 2014
Beth Shapiro Simon Y W Ho

Phylogenetic analyses of ancient DNA data can provide a timeline for evolutionary change even in the absence of fossils. The power to infer the evolutionary rate is, however, highly dependent on the number and age of samples, the information content of the sequence data and the demographic history of the sampled population. In this issue of Molecular Ecology, Sheng et al. (2014) analysed mitoch...

2018
Antonia T Rodrigues Iain McKechnie Dongya Y Yang

Rockfish (Sebastes spp.) are a common marine fish in nearshore and continental shelf environments in the North Pacific Ocean. They are frequently identified in coastal archaeological sites in western North America; however, the morphological similarity of rockfish species limits conventional zooarchaeological identifications to the genus level. This study applies ancient DNA analysis to 96 arch...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید