93 research outputs found
Natural selection in compartmentalized environment with reshuffling
The emerging field of high-throughput compartmentalized in vitro evolution is
a promising new approach to protein engineering. In these experiments,
libraries of mutant genotypes are randomly distributed and expressed in
microscopic compartments - droplets of an emulsion. The selection of desirable
variants is performed according to the phenotype of each compartment. The
random partitioning leads to a fraction of compartments receiving more than one
genotype making the whole process a lab implementation of the group selection.
From a practical point of view (where efficient selection is typically sought),
it is important to know the impact of the increase in the mean occupancy of
compartments on the selection efficiency. We carried out a theoretical
investigation of this problem in the context of selection dynamics for an
infinite non-mutating subdivided population that randomly colonizes an infinite
number of patches (compartments) at each reproduction cycle. We derive here an
update equation for any distribution of phenotypes and any value of the mean
occupancy. Using this result, we demonstrate that, for the linear additive
fitness, the best genotype is still selected regardless of the mean occupancy.
Furthermore, the selection process is remarkably resilient to the presence of
multiple genotypes per compartments, and slows down approximately inversely
proportional to the mean occupancy at high values. We extend out results to
more general expressions that cover nonadditive and non-linear fitnesses, as
well non-Poissonian distribution among compartments. Our conclusions may also
apply to natural genetic compartmentalized replicators, such as viruses or
early trans-acting RNA replicators.Comment: 50 pages, 7 figure
Selection strategies for randomly partitioned genetic replicators
The amplification cycle of many replicators (natural or artificial) involves
the usage of a host compartment, inside of which the replicator express
phenotypic compounds necessary to carry out its genetic replication. For
example, viruses infect cells, where they express their own proteins and
replicate. In this process, the host cell boundary limits the diffusion of the
viral protein products, thereby ensuring that phenotypic compounds, such as
proteins, promote the replication of the genes that encoded them. This role of
maintaining spatial co-localization, also called genotype-phenotype linkage, is
a critical function of compartments in natural selection. In most cases
however, individual replicating elements do not distribute systematically among
the hosts, but are randomly partitioned. Depending on the replicator-to-host
ratio, more than one variant may thus occupy some compartments, blurring the
genotype-phenotype linkage and affecting the effectiveness of natural
selection. We derive selection equations for a variety of such random multiple
occupancy situations, in particular considering the effect of replicator
population polymorphism and internal replication dynamics. We conclude that the
deleterious effect of random multiple occupancy on selection is relatively
benign, and may even completely vanish is some specific cases. In addition,
given that higher mean occupancy allows larger populations to be channeled
through the selection process, and thus provide a better exploration of
phenotypic diversity, we show that it may represent a valid strategy in both
natural and technological cases.Comment: 36 pages, 7 figure
The 'hybrid model' of Norway's ethnic policy in its northern counties: a key to stable interethnic relations
In this article, we study the political and legal model currently used by Norway in its Northern counties. This work is a part of comprehensive research supported by the Russian Science Foundation. Our study aims to provide a historical perspective to the model of Norway’s national ethnic policy in the Northern counties by identifying the operational capabilities and assessing the efficiency of these models amid increasing migration flows and changes in the country’s socio-economic environment. The methods we use in this multidisciplinary study are situated at the interface of national and international law, political science, history, and sociology. They include the comparative historical method (the dynamics of ethno-political processes), the systemic method (ethic policy in the framework of target-based programme management), the comparative law method (a comparison of national legal systems and international contractual standards), the value and norm-driven method (ethnic policy viewed through the prism of public good), institutional method (the role of political institutions), and the secondary analysis of sociological data. We also rely on qualitative methods, namely, the collection, analysis, and interpretation of data on ethnic diasporas living in the North of Norway. As a result, we establish that the Kingdom of Norway has a unified approach to national ethnic policy, which rests on self-confessed multiculturalism. However, different ethnic political models are applied in the case of certain ethnic groups. Today, against the background of declared state multiculturalism and integration, the models of acculturation and non-violent assimilation are both operational in Norway. There are sporadic expressions of nationalism and voluntary segregation. We conclude that, despite a unified approach to ethnic policy and despite Norway’s political and legal achievements in the protection of indigenous peoples’ rights, the country’s government carries out a differentiated ‘hybrid’ ethnic policy towards ethnic groups living on its territory. The growing infighting between the right and the left parties in the Storting translates into unpopular and spur-of-the-moment political decisions as regards inter-ethnic relations
The Language of Mass Architectural Postmodernity
Setting itself off against the architecture of the capitalist West, allegedly tangled in styles, Soviet architecture claimed its origins in the social realm. If one is to trace the intrinsic nature of changes in the architecture of the 1980s in the USSR, it is to be done not through the borrowed concept of postmodernism, but through the analysis of the developments in the design of its most social manifestation—mass housing. So far, Soviet architecture has primarily been whittled down to the evolution of styles. A more advanced reading focuses on the shift from Socialist Realism to the complex design of the human habitat following Khrushchev’s reforms in construction. However, even this transformation took place within the framework of building systematization, represented by the all-Union system of naming for standard architecture, or the Nomenclature. The system, implemented since 1947, assigned indexes to type designs of all building types; within it, every type design was allocated its specific position. The Nomenclature could thus describe the whole human habitat. In the mid-1980s, the naming system made further steps to meet the growing diversification of type designs by assigning new indexes which were longer and codified more parameters, undermining vested geographical and temporal hierarchies. The diversity was treated as a quantitative problem, which the Nomenclature successfully solved. It proved flexible enough to consistently ascribe an index to any—not necessarily type—design. Although mass housing disappeared from the architectural discourse during perestroika, standardized architecture enjoyed the most fruitful and systematic time in its history. So all-encompassing and everlasting, the Nomenclature nevertheless collapsed with the fall of the Soviet Union. The centralization of design proved its most fundamental precondition, which in the post-Soviet world was impossible to retain
A fast iterative algorithm for near-diagonal eigenvalue problems
We introduce a novel iterative eigenvalue algorithm for near-diagonal
matrices termed iterative perturbative theory (IPT). Built upon a
"perturbative" partitioning of the matrix into diagonal and off-diagonal parts,
IPT computes one or all eigenpairs with a complexity per iteration of one
matrix-vector or one matrix-matrix multiplication respectively. Thanks to the
high parallelism of these basic linear algebra operations, we obtain excellent
performance on multi-core processors and GPUs, with large speed-ups over
standard methods (up to x with respect to LAPACK and ARPACK). For
matrices which are not close to being diagonal but have well-separated
eigenvalues, IPT can be be used to refine low-precision eigenpairs obtained by
other methods. We give sufficient conditions for linear convergence and
demonstrate performance on dense and sparse test matrices. In a real-world
application from quantum chemistry, we find that IPT performs similarly to the
Davidson algorithm.Comment: Based on arXiv:2002.1287
Russian Laws on Indigenous Issues (Vol. II) : Wildlife Laws, Concept of Sustainable Development and supplementary legal forms for indigenous communities
publishedVersio
Базовые элементы права на самоопределение коренных народов и их отражение в международных кейсах
The article touches upon the issues of law enforcement and court practice related to the collective rights of aboriginal communities.The purpose of the article is to reveal the content of the right to self-determination through the prism of the most significant cases related to indigenous peoples.The methodological basis of research is the general principles of scientific knowledge, widely used in works in the field of law: system-structural, formal-legal, comparative-legal, historical, methods of analysis and synthesis, analogies, etc. Particular attention was paid to the formal legal method, which was used by the authors of the study to analyze international judicial practice on the rights of indigenous peoples, as well as, in some cases, the national legislation of the countries participating in a particular case.The main results, scope of application. The right to self-determination of indigenous peoples is multicomponent and includes a number of specific elements and facets of interpretation. The authors have made an attempt to reveal the fundamental elements of the right to self-determination of indigenous peoples, which, in their opinion, consist of: the right to sovereignty as such, or autonomy and recognition as collective subjects of law, the right to land and resources, traditional nature management, autonomous education, mothertongue and culture.For each of the above-mentioned elements, a specific case is described, which was considered in international courts, primarily in the International Court of Justice, the Inter-American Court of Human Rights, the ECHR and etc.Conclusions. International recognition of a state through inclusion in the UN General Assembly is impossible without the permission of the Security Council; the issue of “effective occupation” has played and continues to play a large role in the issue of governance and sovereignty over a specific space and territory, and not only settlers, but also traditionally living indigenous peoples play a significant role;Indigenous peoples living in the coastal zone should have the right to dispose of income from the exploitation of the continental shelf; the relationship with the land is not only a matter of ownership and production, but a material and spiritual element that indigenous peoples must fully enjoy, if only to preserve their cultural heritage and pass it on to future generations; the status of “national minority” deprives the indigenous people of priority in the use of land for traditional reindeer herding; means of ensuring freedom of expression of indigenous peoples is an important element for the promotion of identity, language, culture, self-identification, collective rights.В настоящее время государства уделяют всё большее внимание немногочисленным группам своих граждан – коренным народам, их правам и интересам. Причины этого различны, в том числе тенденции гуманизации общества и развития человеческого капитала, а также несомненный вклад коренных народов в сохранение природных ресурсов, окружающей среды, в культурное многообразие мирового сообщества. Специфика существования коренных народов в современном обществе опирается на их особый правовой статус и проявляется преимущественно в традиционном образе жизни, обычном (традиционном) праве, приверженности духовным и религиозным ценностям, что создает условия для сохранения их этнической самобытности. Данные характеристики являются основанием предоставления коренным народам особых прав, которые становятся гарантией гармонии юридического и фактического равенства всех народов, наций, групп в цивилизованном обществе. «Самоопределение» как ядро всей системы прав коренных народов может рассматриваться как право на самую широкую автономию народа в политической, экономической, социальной, культурной сфере. Право на самоопределение закрепляется на международном уровне и реализуется посредством соответствующих политико-правовых институтов, создаваемых в рамках международных соглашений, а также международных судов.Цель статьи – раскрыть содержание права на самоопределение через призму наиболее значимой судебной практики, связанной с коренными народами
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