evolutionary strategies
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Author(s):  
Petr Makuhin ◽  
Stepan Kalinin

Based on observations of the emergence of pidgins, their further extension and transformation into creole languages (all these forms of language are denoted by the term "contact idioms" in this article), the hypothesis is put forward in this part of the exploration that the origin and development of the human language seem to be similar in many dimensions to the emergence and development of contact idioms. In support of that hypothesis, both the general conceptions of some contemporary evolutionary linguists (in particular, D. Bickerton, W.T. Fitch, T. Nikolaeva, B. Bichakjian) are described and evolutionary strategies for some particular languages and language families are surveyed. The similarity of evolutionary vectors of pidgins and creole languages and several of the other language families is assumed. Based on the considered linguistic material, it is postulated that the law "ontogeny manifests a repetition of several phylogenetic stages" or the recapitulationist theory – with all its ambiguousness from the standpoint of present-day biology – seems to be true for linguistic evolution. Attention is focused on the importance of using a comprehensive communicative-discursive approach to the study of glottogenesis, as described in the works of domestic and international linguists who specialize in evolutionary linguistics and general linguistics and whose names are mentioned above. The relevance of the material of contact idioms and languages of other groups and families listed in this paper for such purposes is emphasized.


2021 ◽  
Author(s):  
Nader BuKhamseen ◽  
Ali Saffar ◽  
Marko Maucec

Abstract This paper presents an approach to optimize field water injection strategies using stochastic methods under uncertainty. For many fields, voidage replacement was the dictating factor of setting injection strategies. Determining the optimum injection-production ratio (IPR) requires extensive experience taking into consideration all the operational facility constraints. We present the outcome of a study, in which several optimization techniques were used to find the optimum field IPR values and then elaborate on the techniques? strengths and weaknesses. The synthetic reservoir simulation model, with millions of grid blocks and significant numbers of producers and injectors, was divided into seven IPR regions based on a streamline study. Each region was assigned an IPR value with an associated uncertainty interval. An ensemble of fifty probabilistic scenarios was generated by experimental design, using Latin Hypercube sampling of IPR values within tolerance limits. Scenarios were used as the main sampling domain to evaluate a family of optimization engines: population-based methods of artificial intelligence (AI), such as Genetic algorithms and Evolutionary strategies, Bayesian inference using sequential or Markov chain Monte Carlo, and proxy-based optimization. The optimizers were evaluated based on the recommended IPR values that meet the objective of minimizing the water cut by maximizing oil production and minimizing water production. The speed of convergence of the optimization process was also a subject of evaluation. To ensure unbiased sampling of IPR values and to prevent oversampling of boundary extremes, a uniform triangular distribution was designed. The results of the study show a clear improvement of the objective function, compared to the initial sampled cases. As a direct search method, the Evolutionary strategies with covariance matrix adaptation (ES-CMA) yielded the optimum IPR value per region. While examining the effect of applying these IPR values in the reservoir simulation model, a significant reduction of water production from the initial cases without an impact on the oil production was observed. Compared to ESCMA, other optimization methods have dem


2021 ◽  
Vol 6 (4) ◽  
pp. 265-289
Author(s):  
Gino Cattani ◽  
Franco Malerba

We examine the progress of the evolutionary research on innovation, the firm, and the dynamics of industries in the last four decades. The paper acknowledges that the themes related to knowledge and technological regimes, the evolutionary processes leading to innovation, and the long-term dynamics of technologies have generated, and still remain, relevant research trajectories. The same can be said for the research trajectories on organizational and dynamic capabilities, evolutionary strategies, vertical integration, diversification, niche construction, and authority and power in organizations. Important progress has also been made in understanding the evolutionary trajectories of industries, the link between industry architecture and industry dynamics, the types of knowledge of entrants, the role of focal and vertical spinouts, the relevance of institutions and sectoral innovation systems in industry dynamics, and the catch-up process by firms from latecomer countries. We argue that future developments in the evolutionary camp should continue to be characterized by eclecticism and multidisciplinarity, as well as by the integration of different methodologies from cases to stylized facts, quantitative analyses, appreciative theorizing, and formal modelling. We conclude with an analysis of the main methodologies used by evolutionary scholars and a discussion of the road ahead.


PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0259656
Author(s):  
Stewart Finlayson ◽  
Tyson Lee Holmes ◽  
Geraldine Finlayson ◽  
Rhian Guillem ◽  
Charles Perez ◽  
...  

We tracked pallid swifts (Apus pallidus brehmorum) from a single breeding colony in Gibraltar over two years. Our results show movement of birds between specific regions within the non-breeding geographical area at specific times of the year. The tracking of a single individual showed remarkable fidelity to the areas visited between years. Furthermore, two pallid swifts tracked over the entire eight-month non-breeding period, while in Africa, gave no indication of coming to land, supporting previous findings of an airborne existence in swifts outside the breeding season. In addition, the crossing of the Sahara Desert to and from breeding grounds is remarkably fast, with one individual crossing it in just over a day. We discuss our findings in the context of bird migration evolutionary strategies.


2021 ◽  
Author(s):  
Xinglong Xu ◽  
Jiajie Liu ◽  
Sabina Ampon-Wireko ◽  
Henry Asante Antwi ◽  
Lulin Zhou

Abstract Background The game of interest is the root cause of the non-cooperative competition between urban and rural medical and health institutions. The study investigates competition and cooperation among urban and rural medical institutions using the evolutionary game analysis. Methods With the evolutionary game model, analysis of the stable evolutionary strategies between the urban and rural medical and health facilities is carried out. A numerical simulation is performed to demonstrate the influence of various values. Results The result shows that the cooperation mechanism between urban and rural medical Institutions is relevant to the efficiency of rural medical institutions, government supervision, reward, and punishment mechanism. Conclusions Suggestions for utilizing the government's macro regulation and control capabilities, resolving conflicts of interest between urban and rural medical and health institutions is recommended. In addition, the study again advocates mobilizing the internal power of medical institutions' cooperation to promote collaboration between urban and rural medical and health institutions.


2021 ◽  
Vol 106 ◽  
pp. 372-391
Author(s):  
Ana Carolina Galindo da Costa ◽  
William Wayt Thomas ◽  
Artur Campos D. Maia ◽  
Daniela Maria do Amaral Ferraz Navarro ◽  
Paulo Milet-Pinheiro ◽  
...  

Floral colors and odors are evolutionary strategies used by plants to attract pollinating animals and may be absent in mostly anemophilous groups, such as Cyperaceae. However, considering that insects are floral visitors of some Rhynchospora Vahl species, the objective of this study was to characterize the floral traits and pollination systems within this genus. We analyzed 16 Rhynchospora species with regard to flower morphology, colors of floral structures, floral scents, pollen vectors, and pollination systems. We verified factors that can favor abiotic or biotic pollination in a continuum of floral traits in Rhynchospora. The flower morphology of R. dissitispicula T. Koyama, with inconspicuous brown spikelets in open panicles, is interpreted as a complete adaptation to anemophily. Conspicuous floral traits in Rhynchospora were distinguished from the background by bees. Some species also emit floral volatiles, and we made the first record of floral scent chemistry within the genus. Most of the compounds emitted by these species are known as attractants to many floral-visiting insects. Bees, beetles, and flies visited species with conspicuous floral traits and contributed to fruit set. The investigated floral traits form a continuum across the different pollination systems in Rhynchospora, from anemophilous to ambophilous and then to entomophilous representatives.


2021 ◽  
Author(s):  
Qing Liu ◽  
Chen Liu ◽  
Weicheng Li ◽  
Wenjun Liu ◽  
Qing Liu

Abstract Limosilactobacillus pontis is a species of lactic acid bacteria (LAB) found in fermented milk, sourdough and broiler chickens gastrointestinal tract and so on. However, the evolutionary strategies and genomic characteristics of the species remain unknown, which limits its application. In this study, whole genome sequencing was combined with a comparative genomic approach to investigate genomic characteristics and evolutionary strategies of L. pontis; this includes three published genomic sequences and two strains isolated from fermented milk in Inner Mongolia, China. The mean genome size and GC content of L. pontis was 1.70 Mb and 53.06%, respectively. Within the LAB L. pontis has a high GC content. The phylogenetic tree based on 1,281 core genomes showed that strains from the same sources aggregated together in clusters. Genome information, average nucleotide identity values, and phylogenetic relationships amongst L. pontis from different sources indicated that strains have potential niche adaptability. Functional genomic aspects, GT2 and GT4 (glycosyltransferases, GTs) involved in the synthesis of cellulose and sucrose were the family with the largest number of carbohydrate enzymes in L. pontis, particularly strains isolated from fermented milk. It is worth mentioning that the ability of L. pontis to produce bacteriocin may increase its application potential. This study provides new insight into the genetic characteristics and potential niche adaptations of L. pontis.


Author(s):  
Yu Cao ◽  
Katherine Dever ◽  
Sathesh Kumar Sivasankaran ◽  
Scott V. Nguyen ◽  
Guerrino Macori ◽  
...  

Cronobacter sakazakii is a typical example of a xerotolerant bacterium. It is epidemiologically linked to low moisture foods like powdered infant formula (PIF) and is associated with high fatality rates among neonates. We characterized the xerotolerance in a clinically isolated strain, C. sakazakii ATCC™29544 T , and compared the desiccation tolerance with an environmental strain, C. sakazakii SP291, whose desiccation tolerance was previously characterized. We found that, although the clinical strain was desiccation-tolerant, the level of tolerance was compromised when compared to the environmental strain. RNA-seq based deep transcriptomic characterization identified a unique transcriptional profile in the clinical strain compared to what was already known for the environmental strain. As RNA-seq was also carried out in different TSB growth conditions, genes that were expressed specifically under desiccated conditions were identified and denoted as desiccation responsive genes (DRGs). Interestingly, these DRGs included transcriptomic factors like fnr , ramA, and genes associated with inositol metabolism, a phenotype as yet unreported in C. sakazakii . Further, the clinical strain did not express the proP gene, which was previously reported to be very important for desiccation survival and persistence. Interestingly, analysis of the plasmid genes showed that the iron metabolism in desiccated C. sakazakii ATCC™29544 T cells specifically involved the siderophore cronobactin encoded by the iucABCD genes. Confirmatory studies using qRT-PCR determined that, though the secondary desiccation response genes were upregulated in C. sakazakii ATCC™29544 T , the level of up-regulation was lower compared to that in C. sakazakii SP291. All these factors could collectively contribute to the compromised desiccation tolerance in the clinical strain. IMPORTANCE Cronobacter sakazakii has in past led to outbreaks, particularly associated with food that are low in moisture content. This species has adapted to survive in low water conditions and can survive in such environments for long periods. These characteristics have enabled the pathogen to contaminate powder infant formula, a food matrix with which the pathogen has been epidemiologically associated. Even though clinically adapted strains can also be isolated, there is no information on how the clinical strains adapt to low moisture environments. Our research assessed the adaptation of a clinically isolated strain to low moisture survival on sterile stainless steel coupons and compared the survival to a highly desiccation-tolerant environmental strain. We found that, even though the clinical strain is desiccation-tolerant, the rate of tolerance was compromised compared to the environmental strain. A deeper investigation using RNA-seq identified that the clinical strain used pathways different from that of the environmental strain to adapt to low moisture conditions. This shows that the adaptation to desiccation conditions, at least for C. sakazakii , is strain-specific and that different strains have used different evolutionary strategies for adaptation.


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