Evolutionary perspective

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Changes in diet associated with cancer: An evolutionary perspective

Changes in diet associated with cancer: An evolutionary perspective

3 | CONCLUDING REMARKS While changes in diet are well known in tumor- bearing individuals, a conceptual framework is needed to interpret them. In addition to addressing this gap in knowledge, we highlight here that natu- ral selection could theoretically favor changes in diet that allevi- ate the fitness costs of cancer but that favor at the same time its long- term progression. This is not paradoxical from an evolutionary perspective given that organisms are the result of natural selection to secure the propagation of genes, but not for maintaining good health as long as possible. However, conversely to resistance, such tolerance has dramatic consequences for human health after the reproductive period. Elucidating the relative importance of these two types of defenses is therefore key from an applied medical perspective.
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Evolutionary perspective of cancer: myth, metaphors, and reality

Evolutionary perspective of cancer: myth, metaphors, and reality

The evolutionary perspective on cancer has gained signif- icant international recognition over the past decade and, as all novel scientific paradigms, generated a wave of enthusi- asm among researchers. The heightened interest is under- standable as somatic cellular selection and evolution indeed offer an elegant adaptive explanation for carcinogenesis with its many manifestations (neoangiogenesis, evasion of the immune system, metastasis, and resistance to thera- pies). However, scientists who try to explain oncogenesis will need to critically evaluate the metaphorical comparison of selective processes affecting cancerous cells with those affecting organisms—both similarities and differences need to be carefully considered. This approach seems essential for the applications of evolutionary biology to understand the origin of cancers, to control neoplastic progression, and to improve therapies.
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Environmental policy : an evolutionary perspective

Environmental policy : an evolutionary perspective

This might explain, at least partially, why some countries act in one way and others in another. Questions like: ‘why did Europe singe the Kyoto Protocol when the USA did not?’ could actually be related to some cultural features. How can there prevail different environmental situations in countries which are similar from both an economic and a development perspective?s. It also might be the explanation of why, in the same country or society, some people are more environmentally aware than others. It might the case that some other country specific characteristic could impact on this heterogeneity, like, for example, their income or Gini index.
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An evolutionary perspective on leaf economics: phylogenetics of leaf mass per area in vascular plants

An evolutionary perspective on leaf economics: phylogenetics of leaf mass per area in vascular plants

Despite a sound knowledge of the physiological and ecological correlates of LMA, we remain largely ignorant of the evolutionary history that gave rise to the present- day wide variation in this key trait. Two types of overall evolutionary behavior may be expected for a vegetative trait such as LMA: it can either be evolutionary labile and vary independently from the phylogeny across species, which can lead to high functional convergence across clades (Kraft et al. 2007), or it may alternatively display phylogenetic patterns structured by selection within plant lineages (Blomberg et al. 2003; Losos 2008). In the labile trait hypothesis, we nonetheless expect consistent evolu- tion with other plant traits, or syndromes such as growth form. Recent advances have indeed suggested that the evolution of growth form, as a syndrome of multiple traits, has been a major driver of functional trait evolu- tion (Moles et al. 2005; Kerkhoff et al. 2006). Marked taxonomic patterns in LMA would therefore relate more strongly with growth forms than with phylogenetic relat- edness. Alternatively, following the second hypothesis,
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Reinterpreting Patterns of Variation in Human Thyroid Function: An Evolutionary Perspective

Reinterpreting Patterns of Variation in Human Thyroid Function: An Evolutionary Perspective

Complex interactions exist between pathogen exposure and AITD risk. The Old Friend hypothesis proposes that some contemporary environments deprive humans of the input from microorganisms such as helminthic parasites that induce important regulatory pathways involved in immunotolerance during development (141). The involvement of ‘Old Friends’ in these pathways is the result of a symbiotic co- evolution throughout mammalian evolutionary history. Helminths acquired the capacity to manipulate the host immune system for their own benefit by inducing a modified Th2-type response and regulatory T- and B-cells to down regulate the host’s inflammatory responses (141,142). Some modern lifestyles, lacking this helminth- induced immunoregulation, might therefore predispose to disorders associated with excessive inflammation, including autoimmunity (141,143). In this line, a study in mice shows that prior infection with the helminth Schistosoma mansoni suppresses inflammatory Th1-type immune responses against the TSH-receptor, thereby preventing Graves’ disease development (144). Reintroducing coevolved microbiota has been used as a treatment for some autoimmune diseases such as multiple sclerosis, where helminth therapy shows some beneficial effects, mostly by reducing inflammatory cytokine levels (142). However, in the context of Graves’ disease in mice, helminth therapy is only effective before the aberrant immune response against the TSH-receptor has developed; later introduction of helminths was not effective (144). Further studies are necessary to confirm whether helminth therapy, in the form of helminth-derived immunomodulatory molecules rather than living parasites have a beneficial effect in preventing or treating AITDs in humans, as the safety of using live parasites is still under investigation (183).
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Bioclimatism in Architecture : an evolutionary perspective from vernacular architecture to eco-adaptive architecture

Bioclimatism in Architecture : an evolutionary perspective from vernacular architecture to eco-adaptive architecture

This paper proposes a new perspective of the development of bioclimatic architecture: the perspective of his natural evolution. We can apply evolutionary theory to explain the formation and extinction of some architectural movements. Through a comparative analysis and synthesis, this study has highlighted the perspective of the evolution of bioclimatic

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Bovine noroviruses in Belgium: from a molecular and evolutionary perspective

Bovine noroviruses in Belgium: from a molecular and evolutionary perspective

region)/genotype 2 (capsid region) recombinant strains Recombination as important evolutionary driving force in the genus Norovirus. Positive selection over time for viruses harboring a genotype 2 capsid? „ Very few genetic divergence in the genomes of three genotype 2

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More than a decade of debates in the preeclampsia (island) workshops: a (personally biased) evolutionary perspective.

More than a decade of debates in the preeclampsia (island) workshops: a (personally biased) evolutionary perspective.

This was further demonstrated at the ante-penultian workshop in 2010, which moved from the Indian Ocean to Malaysian waters, in Tioman island, at the Berjaya complex, and this would [r]

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Endogenous growth and environmental policy: are the processes of growth and tertiarisation in developed economies reversible? An evolutionary perspective

Endogenous growth and environmental policy: are the processes of growth and tertiarisation in developed economies reversible? An evolutionary perspective

. Gadrey‟s argument is that service economies, contrary to certain preconceived ideas, are also damaging to the environment. The intangibility of services is not necessarily a criterion of environmental sustainability, since the production of intangible outputs depends directly and indirectly on non-renewable energy and natural resources just as much as that of tangible products does. The other criterion by which services are defined, namely the fact that they are interactive or co-produced (simultaneous physical presence of service provider and customer), is often synonymous with travel and hence with pollution. After all, the service economy is an economy based on mobility (on the part of customers, service providers or the medium of service provision). Furthermore, actually putting this coproduction into practice (known in management sciences as „servuction‟) requires the mobilisation of many tangible elements (physical spaces and technical tools) whose construction, operation and maintenance make use of non-renewable natural resources. From the perspective of coproduction, services appear almost „by nature‟ as particularly environmentally unfriendly.
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Bioclimatism in Architecture : an evolutionary perspective

Bioclimatism in Architecture : an evolutionary perspective

Abstract The well-known Darwinian evolutionary theory (1859) introduced natural selection as the most important mechanism of evolutionary processes at every level from biological systems, including species, individual organisms… to molecules such as DNA or proteins. In architecture we observe similar evolution processes which lead to the development of various architectural movements and concepts from common primitive living structures. Fundamentals of vernacular architecture have been used in bioclimatic architecture which has gradually become the inspiration of various movements in contemporary architecture. The study points out that the development of bioclimatism in architecture has followed the pattern of a natural evolutionary process in which “natural selection” is likely motivated by several factors, including resources and environment problems, and driven by different mechanisms including novel building design concepts and methods, new standards and codes, discoveries in building science and construction costs. This study is an effort aimed to clarify the evolution process of the bioclimatic approach in architecture over time and its influences on contemporary movements in architecture. The paper shows also that the evolutionary theory generated new scientific tools able to improve building design thanks to simulation-based optimization methods applied to building performances. Finally, this study investigates new motivations in the era of climate change whose effects are expected to introduce more challenges as well as more trends towards a sustainable built environment through the new concept of Eco-adaptive architecture.
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The economics of climate change and the change of climate in economics: the implications for climate policy of adopting an evolutionary perspective

The economics of climate change and the change of climate in economics: the implications for climate policy of adopting an evolutionary perspective

More precisely, the added value of the perspective adopted in this PhD research is that it highlights the role played by inertia and path-dependence. Obviously, it is essential to have a good understanding of the underlying causes of that inertia prior to devising on how to enforce a change. Providing a clear picture of the socio-economic processes at play in shaping socio-technical systems is thus a necessary first step in order to usefully complement policy-making in the field of energy and climate change. In providing an analytical basis for this important diagnosis to be performed, the use of the evolutionary framework sheds a new light on the transition towards low-carbon socio-technical systems. The objective is to suggest strategies that could prove efficient in triggering the needed transition such as it has been the case in past “lock-in” stories.
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An evolutionary perspective on the first disulfide bond in members of the cholinesterase-carboxylesterase (COesterase) family: Possible outcomes for cholinesterase expression in prokaryotes

An evolutionary perspective on the first disulfide bond in members of the cholinesterase-carboxylesterase (COesterase) family: Possible outcomes for cholinesterase expression in prokaryotes

3 structurally unrelated additional domains that can simply decorate the common core or bring a new function [8]. For example, members of the S9 protease family acquired a bulky beta propeller domain that covers the active center cavity of the alpha/beta hydrolase subunit and controls the enzyme specificity. The COesterase family is one of these subfamilies that are well represented in eukaryotic genomes. It is named Carboxylesterase_B IPR002018 in the InterPro database [9] and COesterase PF00135 in the PFAM database [10], and it corresponds to Block C in the ESTHER database [11, 12]. This COesterase family emerged from the shuffling of a genomic sequence coding for a N-terminal sequence with a gene coding for a core alpha/beta hydrolase fold scaffold (figure 1). This extra N- terminal sequence increased the length of the polypeptide from ca. 300 to ca. 500 amino acid residues and accordingly the size of the alpha/beta hydrolase subunit. In most cases the additional sequence includes two cysteines separated by up to 65 residues yet spatially close to each other, and whose disulfide bonding ties a ‘Cys loop’ that serves as an important regulator of the various functions of the subfamilies. The second cysteine of the pair belongs to a conserved SEDCLYLN motif which is a signature of the COesterase family (Prosite PS00941: [ED]-D-C-L- [YT]-[LIV]-[DNS]-[LIV]-[LIVFYW]-x-[PQR]). The shuffling is such an ancient event that the members of the family now fold as single domain subunits. For example, in enzymes of the family one can hardly separate the N- terminus extension from the core and still retain enzymatic activity. As well, the making of active chimera implies a high level of homology between the two parental enzymes [13, 14]. Attempts to identify an evolutionary origin of the shuffled N-terminal part failed so far, as no clear homology outside the family was found. The Pfam and Interpro databases sometimes annotate the second cysteine of the first disulfide bond as belonging to a motif of the Ubiquitin- conjugating enzyme family (Prosite PS50127: [FYWLSP]-H-[PC]-[NHL]-[LIV]-x(3,4)-G-x-[LIVP]-C-[LIV]- x(1,2)-[LIVR], where the cysteine is an active center residue, not involved in disulfide bonding) . For example, the cholinesterase-like protein from the King cobra, Ophiophagus hannah (Uniprot: V8P7P1), is annotated that way, and this annotation is propagated in few other cholinesterase entries. However, the serendipity of this annotation suggests that it is a false positive association.
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Promoter Motifs in NCLDVs: An Evolutionary Perspective

Promoter Motifs in NCLDVs: An Evolutionary Perspective

gain and loss, analogously to that reported for the entire genome, which evolved through gene gain and loss. The MEGA-box was slightly modified in the poxviruses lineage, at least concerning the early promoter motif. Considering the intermediate and the late promoter motifs of poxviruses, if they truly came from the MEGA-box, this could have happened through a series of nucleotide loss. However, it is also possible that the emergence of other promoters, rather than the early one, have emerged after the establishment of the poxvirus’ lineage, thus not originating from the ancestral promoter sequence. The same might be true for mimiviruses, phycodnaviruses and iridoviruses. Considering asfavirus and ascoviruses, their promoter sequences might have originated from the MEGA-box through successive gain and loss of nucleotides. However, another scenario is also possible, wherein their promoter motifs emerged from the poxviruses and iridoviruses lineages respectively (closest evolutionary groups). This scenario is in agreement with the proposition that the Megavirales’ ancestor was already a giant virus with a large genome [ 10 ]. In this aspect, the giant ancestor also had a large promoter sequence that evolved through constant nucleotide gain and loss, a pattern analogous to the accordion-like model of genome evolution. However, other scenarios are also possible, although less probable, considering the evolutionary data currently available for these viruses. One is that the ancestor had a very short promoter sequence, like a poxvirus intermediate promoter (TAAA), that underwent massive nucleotide gain over time, leading to very large promoter sequences in the majority of the giant viruses. Another one is just the opposite; wherein the ancestor had a very large promoter region that had been losing nucleotides during evolution. A third pathway, equally unlikely, would be the acquisition of promoter sequences by horizontal/lateral transfer. Similar to different genes, the MEGA-box promoter evolutionary pattern during the radiation of NCLDVs members could be related to the co-evolution with different hosts over time.
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Transmissible Cancers in an Evolutionary Perspective

Transmissible Cancers in an Evolutionary Perspective

INTRODUCTION Although rare, transmissible cancers are among the most intriguing and unexplored host-pathogen systems. The pathogens are clonal infectious malignant cell lines that originated in an individual within the host species or from a closely related species, and spread horizontally as allografts and/or xenografts. The vast majority of cancer cells that emerge in multicellular organisms die with their host, but evolutionary principles predict the ex- istence and find cancer cell lineages that can escape the death by becoming contagious, acquire higher fitness, and consequently will be favored by selection (topic reviewed in Ujvari et al., 2017 ). Once the cancer cells have adapted to the normal barriers that prevent host-to-host transmission, they are subject to the evolutionary dy- namics of infectious agents. They are, in effect, a new parasitic ‘‘species’’ ( Dingli and Nowak, 2006 ). Currently, transmissible cancers have only been documented in three animal groups that occupy both terrestrial and ma- rine environments and appear to result from the confluence of several environmental, host, and cell factors (the ‘‘perfect storm theory,’’ Ujvari et al., 2016a ). Transmissible cancers have been proposed to have existed since the transition to multicellularity ( Metzger and Goff, 2016 ). The evolution of multicellular organisms required that in- dividual cells forgo their own reproductive interests, i.e., shifting the Darwinian unit of selection from individual cells to the entire multicellular community. However, the division of labor and specialization by differentiated cells in multicellular organisms also provided opportunities for these tissues to be colonized by fast proliferating cheater cells that take advantage of the benefits of multicellular tissue (e.g., blood flow) while not performing a differentiated function. To prevent colonization, multicellular organisms evolved defense mechanisms that may include sexual reproduction ( Thomas et al., 2019 ) ( Figure 1 ) and the development of immune systems ( Metzger et al., 2015 ; Murchison, 2008 ; Murgia et al., 2006 ).
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State-Policy Dynamics in Evolutionary Games

State-Policy Dynamics in Evolutionary Games

1.1 Motivations and applications The scenario proposed in this paper finds its first motivation in the study of optimal power control policies in wireless networks [12]. MDP is a suitable mathematical structure to study optimal problems in stochastic environment. When considering interactions between several decision makers, competitive MDP and stochastic games are useful tools. Our framework aims to enlarge this family of models, by considering evolutionary perspective in the game and then creating a link with dynamical systems. In fact, evolutionary games can be interpreted as a dynamical system through the Replicator Dynamics equations. Thus, since previous works only analyzed the evolutionary stability concept, we propose in this paper a study of the dynamical aspect of this framework. The usefulness of the paper is related to the applications that can be studied based on it. In Information and Communications Technology, our framework finds many application domains like social networks, crowd sourcing and Internet of Things (IoT). For example, emerging applications in engineering such as crowd-sourcing and (mis)information propagation involve a large population of heterogeneous users or agents in a complex network who strategically make dynamic decisions. These agents interact with each other in a complex environment, in which each agent makes strategic and dynamic decisions in response to the agents it interacts with. In all these applications, the action set of each agent depends on a local state. For example, in social networks, each agent may decide to add/remove friends/news based on his own current status. His decision impacts his own status dynamics but also the interaction with other agents. In IoT, a sensor has to determine when to upload his information to the fusion center. This decision impacts his battery level but also the communication quality as collisions may occur for example. As pointed out in several references cited above, the Replicator Dynamics equations are related to several learning algorithms that can be implemented in such sensors or actuators in IoT. Then, by studying these equations, we can understand the convergence behaviour of decentralized algorithms that can be used in such applications. Finally, we would like to mention that our framework is totally coherent with the ideas developed in [13], quoting: From an engineering point of view, one of the main benefits of multi-agent learning (highly linked to the Evolutionary dynamics like the RD) is its potential applicability as a design methodology for distributed control, which is a branch of control theory that deals with design and analysis of multiple controllers that operate together to satisfy certain design requirements.
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Computing an Evolutionary Ordering is Hard

Computing an Evolutionary Ordering is Hard

LBBE, Universit´ e Lyon 1, France Abstract A family of sets is evolutionary if it is possible to order its elements such that each set except the first one has an element in the union of the previous sets and also an element not in that union. This definition is inspired by a conjecture of Naddef and Pulleyblank concerning ear decompositions of 1-extendable graphs. Here we consider the problem of determining whether a family of sets is evolutionary. We show that the problem is NP-complete even when every set in the family has at most 3 elements and each element appears at most a constant number of times. In contrast, for families of intervals of integers, we provide a polynomial time algorithm for the problem.
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SPECIAL CLEAN AND PERSPECTIVE ELEMENTS AND PERSPECTIVE RINGS

SPECIAL CLEAN AND PERSPECTIVE ELEMENTS AND PERSPECTIVE RINGS

To conclude this section, we make the link between perspectivity, stable range 1 and (special) clean decompositions more precise at the level of elements. It is indeed known ([?, Theorem 3.5]) that a regular element of a ring has left (equivalently right) stable range 1 iff it is unit-regular. In rings with stable range 1 (in particular unit-regular ones) regular elements have right and left idempotent stable range 1, where a ∈ R has right idempotent stable range 1 if for all b ∈ R, ax + by ∈ U (R) for some x, y ∈ R implies that a + be ∈ U (R) for some e ∈ E(R). We prove that left perspective elements are precisely regular elements with outer inverse right stable range 1, where a ∈ R has outer inverse right stable range 1 if aR + bR = R for some b ∈ R implies that a + bx ∈ U (R) for some outer inverse x ∈ R of b.
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Evolutionary identification of macro-mechanical models

Evolutionary identification of macro-mechanical models

The genetic operators are crossover, standard mutations (change of function, in­ sertion of a random subtree or promotion of a subtree), plus Gaussian mutation to adjust the floating-[r]

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Constructing practice on evolutionary knowledge in ECEC

Constructing practice on evolutionary knowledge in ECEC

From the question of giving more freedom of move- ment, knowledge about this topic used in a Belgian curriculum, the article illustrates the importance of consider- ing practice not as a[r]

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The architect’s perspective on the tour and map perspective

The architect’s perspective on the tour and map perspective

The expressions of transition are shown in the diagrams in red color and the reference to the body would be marked in green color but as it is evident in the graphical representation the internal reference is totally absent (fig. 4). The lack of specificity in terms of connectivity of spaces is also evident in the map perspective. To a certain degree this probably happens because it is a hypothetical scenario of space and the person does not have a very specific spatial organization in mind. We can also assume, given the association between tour narratives and memory of experienced space, that when imagining an ideal space the reference to the body is absent because the space has not been yet “inhabited.” It should be noted here that most students showed great surprise when were asked this question since they were forced to come up with an architectural solution almost instantly and only by mentally representing it.
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