First Stage Of Evolution Research Articles

Notes on the general relativistic viscous ringed disk evolution

Abstract A ringed accretion disk (RAD) models a cluster of axi-symmetric co-rotating and/or counter-rotating tori orbiting in the equatorial plane of a central Kerr super-massive Black Hole. We discuss the time evolution of such a ringed disk within the general relativity framework. Our analysis presents a study of the evolving RAD properties using a thin-disk scheme and solving a diffusion-like evolution equation for a RAD in the Kerr spacetime. In the first stage of evolution there is the inter–disk interaction where the individual rings spread inwardly and outwardly, levelling the structure and forming a single distribution with maximum density determined by the initial spread of the component rings. Timescales are dependent on viscosity prescriptions. The early time luminosity, dominated by the dynamics of the inner ringed structure, shows a clear mark of the inner ringed structure. The RAD eventually reaches a single disk phase, building accretion to the inner edge regulated by the inner edge boundary conditions. The late–time luminosity associated to the ringed disk follows a power law decline for the final single disk. In the sideline of this analysis we also considered a modified prescription mimicking an effective turbulent viscosity in the early phases of the rings evolutions.

Host galaxy of low-luminosity compact sources

The term `active galactic nuclei' (AGN) is applied to a huge variety of objects, classified on the basis of their properties at different wavelengths. Peaked sources (PSs) represent a class of AGN at the first stage of evolution, characterised by a peaked radio spectrum. Among these radio sources, low-luminosity compact (LLC) sources can be identified as PSs accreting with a high Eddington rate, harbouring low-power jets, and hosting low-mass black holes. These properties are also shared by narrow-line Seyfert 1 galaxies (NLS1s). In 2016, LLCs were hypothesised to be the parent population of NLS1s with a flat radio spectrum (F-NLS1s), suggesting that the former may be the same objects as the latter but, instead, seen at a higher inclination. Based on radio luminosity functions and optical spectra analysis, ten LLCs were identified as valid F-NLS1s candidates. To account for the missing piece to the puzzle and verifying whether these LLCs could be hosted in late-type galaxies as NLS1s, we performed a photometric decomposition of their Pan-STARRS1 images in all five filters. We used the 2D fitting algorithm GALFIT for the single-band analysis and its extension GALFITM for the multi-band analysis. Considering that the morphological type and the structural parameters of the host may be dependent on the wavelength, we found six out of ten LLCs hosted in late-type galaxies, probably with pseudo-bulges, along with three point-like sources and one object of an uncertain classification. Although this study is based on a small sample, it represents the first morphological analysis of LLC host galaxies. These results confirm the trend observed in NLS1s, indicating late-type and disc-like host galaxies for LLCs and supporting the validity of the parent population scenario.

A two-stage bidirectional coevolution algorithm with reverse search for constrained multiobjective optimization

Constrained multiobjective optimization problems (CMOPs) are widespread in reality. The presence of constraints complicates the feasible region of the original problem and increases the difficulty of problem solving. There are not only feasible regions, but also large areas of infeasible regions in the objective space of CMOPs. Inspired by this, this paper proposes a bidirectional coevolution method with reverse search (BCRS) combined with a two-stage approach. In the first stage of evolution, constraints are ignored and the population is pushed toward promising regions. In the second stage, evolution is divided into two parts, i.e., the main population evolves toward the constrained Pareto front (CPF) within the feasible region, while the reverse population approaches the CPF from the infeasible region. Then a solution exchange strategy similar to weak cooperation is used between the two populations. The experimental results on benchmark functions and real-world problems show that the proposed algorithm exhibits superior or at least competitive performance compared to other state-of-the-art algorithms. It demonstrates BCRS is an effective algorithm for addressing CMOPs.Graphical

A connection between regular black holes and horizonless ultracompact stars

We illustrate that regular black holes and horizonless stars, typically considered as quite distinct families of black hole mimickers, are intimately intertwined. We show that any spherically symmetric regular black hole can be continuously deformed into a horizonless star under the mild conditions of non-negativity of gravitational energy (Misner-Sharp quasi-local mass), and an assumed linear relation between the latter and the Arnowitt-Deser-Misner (ADM) mass. We illustrate this general result by considering the family of geometries proposed by Hayward as the description of regular black holes, and we also describe the properties of the corresponding horizonless stars. The form of the associated effective stress-energy tensor shows that these horizonless stars can be identified as anisotropic gravastars with a soft surface and inner/outer light rings. We also construct dynamical geometries that could describe the evolution of regular black holes towards horizonless stars, and show that it is plausible that the effective stress-energy tensor in the first stages of evolution is generated by semiclassical effects, in agreement with independent works analyzing semiclassical backreaction.

Conversion of Escherichia coli into Mixotrophic CO2 Assimilation with Malate and Hydrogen Based on Recombinant Expression of 2-Oxoglutarate:Ferredoxin Oxidoreductase Using Adaptive Laboratory Evolution

We report the mixotrophic growth of Escherichia coli based on recombinant 2-oxoglutarate:ferredoxin oxidoreductase (OGOR) to assimilate CO2 using malate as an auxiliary carbon source and hydrogen as an energy source. We employ a long-term (~184 days) two-stage adaptive evolution to convert heterotrophic E. coli into mixotrophic E. coli. In the first stage of evolution with serine, diauxic growth emerges as a prominent feature. At the end of the second stage of evolution with malate, the strain exhibits mixotrophy with CO2 as an essential substrate for growth. We expect this work will open new possibilities in the utilization of OGOR for microbial CO2 assimilation and future hydrogen-based electro-microbial conversion.

Petrogenetic and textural classification of kimberlites and lamproites of the Brauna Kimberlitic Field: Implications for potassic/ultrapotassic magmatism in the São Francisco Craton

Kimberlitic rocks are known in the São Francisco Craton, Brazil, since the 1980s when the De Beers started a prospective work in the Itapicuru River Greenstone Belt. However, 40 years later, the scientific knowledge about these occurrences is still very restricted. This paper presents new geological and petrographical data for the pipes of the “Brauna Kimberlitic Field”. These rocks are exposed in a strongly eroded cratonic area of Northeastern São Francisco Craton and as expected, represent the deepest parts of these bodies, showing textural aspects and components typical of coherent volcanic rocks emplaced at deep crustal levels.The kimberlitic magmatic event resulted not only in the emplacement of macrocrystalline hypabyssal olivine archetypal kimberlites, here represented by the B3 (678–682 Ma) and B4 pipes (s.s. Former type 1 kimberlites), but also in hypabyssal macrocrystalline pyroxene-phlogopite- lamproite intrusions, as exposed in the B7 (641 Ma) pipe of the Brauna Field. Both magmas are rich in mantle-xenoliths and have potential for diamond ores. The observed features suggest the presence of multiple magmatic pulses – which acted as deep samplers, recorded in the diversity of xenoliths and xenocrysts – thus demonstrating the potential of these rocks for the comprehension of the first stages of evolution of the Early Earth as well as for understanding the formation of the metasomatized lithospheric mantle below the São Francisco Craton.The new data for these hypabyssal facies, macrocrystic pulse of kimberlitic rocks in the Brauna Field, São Francisco Craton, Brazil, can be used to characterize the petrographic and mineralogical heterogeneities of a Neoproterozoic alkaline-ultrapotassic magmatic event that shows a kimberlite-lamproite transitional nature. The petrogenetic knowledge presented for the São Francisco Craton kimberlites and lamproites – accordingly to the most recent classifications for these rocks – include textural-genetic data, geotectonic environment, and intrusive-spatial context, setting these rocks at the stage 5 of present-day kimberlite classification scheme. Moreover, the integration of such data and the close spatial associations of kimberlites, lamproites, lamprophyres, syenites and shoshonites allowed to create a solid interpretation of the rock formation processes that correlates these Neoproterozoic alkaline ultrapotassic magmas to the reactivation of ancient mantle conduits in a thick lithosphere that overlies a previously metasomatized mantle and intrude a metal-rich craton environment.

Генезис и развитие адыгской литературы: проблемы стадиальных состояний и периодизации

The purpose of the research is to solve the issue of stage states and periodisation of the Adyghe literature. Scientific novelty of the work lies in identifying not one (which is all the pre-war decades) but two periods of active interaction with the Russian culture. As a result, it is found that attribution of the first stage in evolution of the Adyghe Soviet literature should be based on ideological principles. Ideally, it can be made only within coordinates of donor - acceptor relations with the Russian Soviet verbal tradition and the entire system of the socialist realist culture, which really defined norms of national writers’ aesthetic beliefs.

Evolution of legal regulation of activity forms of members of representative bodies of local self-government in the Ukrainian lands within Austria-Hungary and pre-revolutionary Russia

The article deals with historical and legal aspects of the normative regulation of the forms of activity of the representative bodies of local self-government and their members on the Ukrainian lands, which were part of Austria-Hungary and pre-revolutionary Russia. It is shown that during the 60-90s of the XIX century, there was an accumulation of experience in the normative consolidation of the legal status and organization of the work of local representative bodies, the formation of the main forms of their activity. Attention is drawn to the fact that in both empires the adoption of liberal legislation on local self-government led to the activation of local rule-making. The content of national and local acts regulating the forms of activity of representative bodies of the late XIX – early XX centuries is analyzed. In its modern form, local government developed in the nineteenth century. as a result of the victory of liberal-democratic reforms in the world's leading states. Therefore, consideration of the evolution of legal regulation of the forms of activity of deputies of domestic local representative bodies should begin in the 1860s, when in Austria-Hungary and the Russian Empire, which at that time included Ukrainian lands, local government began almost simultaneously. The period of functioning of representative bodies of local self-government in the Ukrainian lands as a part of Austria-Hungary and pre-revolutionary Russia (1862-1917) should be considered as the first stage of evolution of forms of activity of deputies of local councils in modern Ukraine. This was the stage of initiating the normative consolidation and practice of implementing the forms of activity of the deputy corps of domestic representative bodies of local self-government.

Interdependence between networks and member firms in the evolution of inter-organizational networks

Abstract Cooperation among firms through networks is a form to obtain a variety of resources. Over time, networks can become an exclusive provider of some resources used by members, leading to dependencys. This study is interested in this phenomenon, and aims to examine how firm-network interdependence grows throughout the development of inter-organizational networks. The research was conducted with networks that were in distinct stages of evolution (formation, development, and professionalization). Interviews were carried out with the presidents of the networks and two member firms of each network. The study identified an inversion in the relation of interdependence investigated, where the network is dependent of its members in the first stages of evolution and, as its governance and structure consolidate, members develop a dependency relationship toward the network and the benefits it offers.

Interdependence between networks and member firms in the evolution of inter-organizational networks

Abstract Cooperation among firms through networks is a form to obtain a variety of resources. Over time, networks can become an exclusive provider of some resources used by members, leading to dependencys. This study is interested in this phenomenon, and aims to examine how firm-network interdependence grows throughout the development of inter-organizational networks. The research was conducted with networks that were in distinct stages of evolution (formation, development, and professionalization). Interviews were carried out with the presidents of the networks and two member firms of each network. The study identified an inversion in the relation of interdependence investigated, where the network is dependent of its members in the first stages of evolution and, as its governance and structure consolidate, members develop a dependency relationship toward the network and the benefits it offers.

Evolution mechanisms and fundamental equations of social water cycle fluxes

Abstract The rise of socio-hydrology, addressing the interactions between human and water systems, is regarded as an innovative perspective to researches achieving the sustainable use of water resources. Revealing the social water fluxes, in terms of magnitude, structure, and variations under changing environment, could advance the understanding of water cycling under the dual driving forces: natural and anthropogenic. This study attempts to formulate the fundamental equations of the social water cycle by focusing on the evolution mechanisms of social water cycle fluxes. The endogenously dynamic characteristics of social water cycling are portrayed, i.e., the gradual change mechanism and the catastrophe mechanism, therefore dividing the evolution processes into four stages. Then, social water cycle flux reaches its peak and completes the first stage of evolution. The evolution process is an S-shaped curve process. After the peak, it enters the next evolutionary stage, where the pattern varies with the intensities of the gradual change mechanism and the catastrophe mechanism. The coordination relationships of these two mechanisms and the fluctuating characteristics in each stage are studied as well. Case studies are investigated in 39 countries globally to verify the fitting of the fundamental equations and evolution mechanisms.

Гражданская постройка («баня») в Переяславле и архитектура резиденций русских архиереев XI–XV веков

According to the Russian chronicles, metropolitan Ephrem initiated an intensive building program in the city of Pereyaslavl’ in the last quarter of the 11th century. Besides the cathedral, the chronicles mention stone walls, a gate with a church over it, a church near this gate, a bath-house and “other buildings”. This building program indicates that Ephrem of Pereyaslavl’ intended to erect an official residence for the metropolitans/bishops of the princedom. It is highly likely that the bath-house project was inspired byEphrem’s experience as a monk of an unknown Constantinopolitan monastery. The typika of the monasteriesin the Byzantine capital testify that it was the very time of the rising concern with the hygiene issues within the monastic society. It has been tentatively proposed that the civil building of the 11th century within the fortress of Pereyaslavl’ might be identified as Ephrem’s bath-house. This monument is in a poor state of preservation; however, the archaeologists were able to find six pieces of ceramic tubes, along with the fragments of elaborate decor of the building. The studied bath-houses of the middle Byzantine period throughout all EasternChristian countries demonstrate uniformity and consistency of their layouts. They are hardly matched with the civil building in Pereyaslavl’. Ceramic tubes being put aside, there is no archaeological evidence in favor of its functioning as a bath-house. Therefore, for today this secular building should be considered as a part of the palatial complex of the metropolitan. The study of this ensemble should be continued, being a key issue for understanding the first stage of evolution of the ecclesiastical residences in Old Rus’.

Authentic Leadership: Getting Back to the Roots of the ‘Root Construct’?

AbstractIn their 2011 review paper, Gardner et al. (Authentic Leadership: a review of the literature and research agenda. Leadership Quarterly, 22, pp. 1120–1145) concluded that the authentic leadership (AL) construct was still in the first stage of evolution, that of concept introduction and evaluation. At that time, the field was characterized by two types of contribution: conceptual expositions and largely quantitative research seeking to map out its antecedents and consequences, moderators and mediators. The current review aims to: (1) critically evaluate the development of the AL construct to the present time; and (2) taking this evaluation as a point of departure, propose the need for a radical re‐grounding of understanding of AL aimed at countering what the authors believe to be the substantive flaws in both its philosophical underpinnings and empirical grounding. The authors propose that these shortcomings have arisen owing to the failure of existential and other critiques of the dominant (normative and functionalist) discourse of AL to gain traction, and owing to an absence of practice‐based, qualitative research. As a strategic platform for the potential re‐grounding and relaunch of AL, the authors propose a radical return to the existential and practice roots of authenticity as the basis for a broader understanding of ‘authentic leadership’ as a ‘central organizing principle’ in leadership studies. Despite the flaws identified in the AL construct, the authors suggest that the notion of authenticity may still have a valuable role to play in the study of leadership: that role, however, can only be determined through a thorough understanding of AL as a practice‐based phenomenon.

Evolutionary Origin of the Staphylococcal Cassette Chromosome mec (SCCmec).

Several lines of evidence indicate that the most primitive staphylococcal species, those of the Staphylococcus sciuri group, were involved in the first stages of evolution of the staphylococcal cassette chromosome mec (SCCmec), the genetic element carrying the β-lactam resistance gene mecA However, many steps are still missing from this evolutionary history. In particular, it is not known how mecA was incorporated into the mobile element SCC prior to dissemination among Staphylococcus aureus and other pathogenic staphylococcal species. To gain insights into the possible contribution of several species of the Staphylococcus sciuri group to the assembly of SCCmec, we sequenced the genomes of 106 isolates, comprising S. sciuri (n = 76), Staphylococcus vitulinus (n = 18), and Staphylococcus fleurettii (n = 12) from animal and human sources, and characterized the native location of mecA and the SCC insertion site by using a variety of comparative genomic approaches. Moreover, we performed a single nucleotide polymorphism (SNP) analysis of the genomes in order to understand SCCmec evolution in relation to phylogeny. We found that each of three species of the S. sciuri group contributed to the evolution of SCCmec: S. vitulinus and S. fleurettii contributed to the assembly of the mec complex, and S. sciuri most likely provided the mobile element in which mecA was later incorporated. We hypothesize that an ancestral SCCmec III cassette (an element carried by one of the most epidemic methicillin-resistant S. aureus clones) originated in S. sciuri possibly by a recombination event in a human host or a human-created environment and later was transferred to S. aureus.

EVOLUTION OF KREMLINS AS EVOLUTION OF RUSSIAN URBAN SETTLEMENTS

The Kremlin is considered to be the first stage of evolution of the urban settlement in the period of strengthening of the Russian centralized state. Five main functions of the kremlin were identified. By now, some functions of Kremlins have been transformed or replaced as a result of turning them into museums. At the kremlin, the focus is harmoniously shifting from one function to another. The kremlin ensemble evolves with the urban settlement. Formation and development of Kremlins is a phenomenon of the world heritage, a starting point of unique Russian city formation. In order to introduce the concept of the “Russian Kremlin” as a phenomenon to the world community, its basic attributes and key definitions were determined. The current role of preserved kremlin complexes in municipal structures was estimated.

Stellar models simulating the disk-locking mechanism and the evolutionary history of the Orion Nebula cluster and NGC 2264

Rotational evolution in young stars is described by pMS evolutionary tracks including rotation, conservation of angular momentum (AM), and simulations of disk-locking (DL). By assuming that DL is the regulation mechanism for the stellar angular velocity during the early stages of pMS, we use our models and observational data to constrain disk lifetimes (Tdisk) of a sample of low-mass stars in the ONC and NGC2264. The period distributions of the ONC and NGC2264 are bimodal and depend on the stellar mass. To follow the rotational evolution of these two clusters' stars, we generated some sets of evolutionary tracks. We assumed that the evolution of fast rotators can be modeled by considering conservation of AM during all stages and of moderate rotators by considering conservation of angular velocity during the first stages of evolution. With these models we estimate a mass and an age for all stars. For the ONC, we assume that the secondary peak in the period distribution is due to high-mass objects locked in their disks, with a locking period (Plock) of ~8 days. For NGC2264 we make two hypotheses: (1) the stars in the secondary peak are locked with Plock=5 days, and (2) NGC2264 is in a later stage in the rotational evolution (this implies in a DL scenario with Plock=8 days, a Tdisk of 1 Myr and, after that, constant AM evolution). We simulated the period distribution of NGC2264 when its mean age was 1 Myr. Dichotomy and bimodality appear in the simulated distribution, presenting one peak at 2 days and another one at 5-7 days, indicating that the assumption of Plock=8 days is plausible. Our hypotheses are compared with observational disk diagnoses available in the literature. DL models with Plock=8 days and 0.2 Myr<=Tdisk<=3 Myr are consistent with observed periods of moderate rotators of the ONC. For NGC2264, hyphotesis 2 is the more promising explanation for its period distribution.

Designing a Hybryd Equipment for Additive Manufacturing

In terms of the development of 3D printers we can say that in the first stage of evolution the huge majority of them were able to print 3D using 3 axis numerically controlled. Currently there are several types of printers that can print in 4 and 5-axis developed using classical solutions (portal or parallel structure). Another direction of development is the combination of 3D printers and traditional manufacturing equipment, with an already existing commercial solution (Hermle MPA 40) that combines milling and MPA technology (Metal Powder-Application). This paper presents a hybrid equipment that can be placed in the specific additive manufacturing category, combining milling operations (4 axis) and turning with 3D printing using FDM technology. The machine uses stepper motors for driving kinematic axes, a DC motor (16 000 rev / min) to drive the main shaft of the mill and a three-phase motor for turning. The software used for milling and turning is Mach3, while MatterControl is used for 3D printing.

Fluvial islands: First stage of development from nonmigrating (forced) bars and woody-vegetation interactions

Fluvial islands can develop from the channel bed by interactions between pioneer trees and bars. Although vegetation recruitment and survival is possible on all bar types, it is easier for trees to survive on nonmigrating bars developed from a change in channel geometry or to the presence of a steady perturbation. This field study details the first stages of development of a vegetated mid-channel, nonmigrating (or forced) bar and its evolution toward an island form. Over six years, analysis of bed topographical changes, vegetation density and roughness, scour and fill depths, sediment grain size and architecture, and excess bed shear stress highlighted a specific signature of trees on topography and grain size segregation. Two depositional processes combining the formation of obstacle marks and upstream-shifting deposition of sediments led to the vertical accretion of the vegetated bar. During the first stage of the bar accretion, bedload sediment supply coming from surrounding channels during floods was identified as a key process modulated by the presence of woody vegetation and a deflection effect induced by the preexisting topography. Grain size segregation between vegetated and bare areas was also highlighted and interpreted as an important process affecting the development of surrounding channels and the degree of disconnection (and hence the speed of development) of a growing island. The heterogeneity of bedload supply can explain why sediment deposition and density of trees are not strictly related. A general conceptual model detailing the first stages of evolution from a bar to an established island is proposed for relatively large lowland rivers.

Condensation kinetics at high supersaturations

This work is devoted to the kinetics of a first-order phase transition. The evolution of distribution if stable-phase nuclei at high supersaturations, when the discreteness of nuclei sizes becomes significant, is investigated. For the sake of definiteness, the growth of multivacancies in the material irradiated by neutrons is considered under the condition that the degree of supersaturation of the “gas” in a vacancy is high. The first stage of evolution characterized by a small total number of vacancies in multivacancies and time-independent degree of supersaturation is described. The second stage at which the number of vacancies in multivacancies cannot be disregarded and supersaturation gradually decreases is briefly discussed.

Transverse folding and evolution of the hind wings in beetles (Insecta, Coleoptera)

Sharp intensification of the protective function of the fore wing in Coleoptera has made their flight apparatus posteromotoric and initiated the development of an apparatus for folding the hind wings beneath the elytra. This could hardly take place without a higher deformability of veins relative to each other, which diminished the strength properties of the wing support. The effect has been stressed by the presence of folds. The wing support and folding pattern evolved as interrelated: the former evolved to be more flexible, with no or minimum loss of rigidity; the latter evolved to be less harmful for the supporting structures. The only function performed, as well as simple structure and low specialization of folds made the folding pattern highly labile in the course of evolution. It evolved superior to wing venation, thus defining many transformations of the latter. This evolutionary conservatism of wing venation stemmed from the fact that many veins performed two conflicting functions. For this conflict to be resolved an adaptive compromise was needed, which brought the wing to orthogenetic development. The main evolutionary trends in wing venation and the folding pattern were those towards simplification and higher complexity, respectively. The coleopteran wing has passed two main evolutionary stages. The major evolutionary factors were wing posteromotorism at the first stage of evolution, with a trend toward miniaturization at the second stage. Each stage resulted in the development of a particular wing type, archostematan and “cantharoid”, respectively. They differ fundamentally. In the wing of the former type, the folding and flight apparatus constitute a steady coadaptive ensemble, because their supporting systems overlap considerably. This wing remained stable through evolution, and its structural variations were only minor deviations from the ground plan. The development of the “cantharoid” wing type was an upgrade of the morphofunctional organization. The region of maximum transverse deformations initiated by folding was extruded bayond the basal, supporting, part of the remigium, which contributed much to rigid properties of the chief supporting axes. The two wing apparatus have become more autonomous after acquiring the above structure. This expanded the range of possible specialization and gave rise to a great variety of derived wing types.