scholarly journals Chemical roots of biological evolution: the origins of life as a process of development of autonomous functional systems

Open Biology ◽  
2017 ◽  
Vol 7 (4) ◽  
pp. 170050 ◽  
Author(s):  
Kepa Ruiz-Mirazo ◽  
Carlos Briones ◽  
Andrés de la Escosura
Keyword(s):  
Molecular Species ◽  
Evolutionary Dynamics ◽  
Biological Evolution ◽  
Control Mechanisms ◽  
Molecular Control ◽  
Functional Systems ◽  
Selection Processes ◽  
Prebiotic Chemical ◽  
The Individual

In recent years, an extension of the Darwinian framework is being considered for the study of prebiotic chemical evolution, shifting the attention from homogeneous populations of naked molecular species to populations of heterogeneous, compartmentalized and functionally integrated assemblies of molecules. Several implications of this shift of perspective are analysed in this critical review, both in terms of the individual units, which require an adequate characterization as self-maintaining systems with an internal organization, and also in relation to their collective and long-term evolutionary dynamics, based on competition, collaboration and selection processes among those complex individuals. On these lines, a concrete proposal for the set of molecular control mechanisms that must be coupled to bring about autonomous functional systems, at the interface between chemistry and biology, is provided.

scholarly journals The rich get richer and the poor get poorer - the Matthew mechanism as an approach to explain selection effects and the occurrence of multiple medalists in the "production" of international success in alpine ski racing

2018 ◽  
Author(s):  
Michael Barth ◽  
Arne Güllich ◽  
Eike Emrich
Keyword(s):  
Turnover Rate ◽  
Social Mechanisms ◽  
High Concentration ◽  
Socialization Process ◽  
National Team ◽  
Selection Processes ◽  
The Rich ◽  
The Individual ◽  
International Success

The study addresses two questions that are under debate in the literature and exemplifies their examination in alpine ski racing. Firstly, are successful athletes the product of a long-term continuous intervention and/or socialization process or do they rather emerge via repeated selection processes? Secondly, to which extent is a nations’ collective success composed of many athletes’ singular successes or of a few athletes’ multiple successes?The study involved the national squad of the Austrian Ski Federation. Data collection comprised membership in a national squad and World or Olympic medal success and was carried out via document analysis (seasons: 1986-2016).The mean annual athlete turnover rate ranged from 24-57% across squad levels while the turnover rate varied substantially over time within each squad level. Among all national squad athletes, the incidence of being a successful (i.e., medal winning) National Team athlete was 8.9% (95% CI: 6.0%; 12.5%). Twenty-eight athletes won a total of 112 medals, 21 athletes achieved winning two or more medals. The six most successful athletes won 56 medals, comprising 50% of all medals won.The study suggests that successful elite athletes emerge from repeated selection and filtering processes. The observation of multiple medalists and a high concentration of exceptional success among a few athletes is reflected with regard to potential causes that rest on characteristics of the individual athlete, on social mechanisms (e.g., Matthew mechanism) of the elite sports system, or both.

scholarly journals The Many Facets of Evolutionary Dynamics

1997 ◽  
Vol 05 (03) ◽  
pp. 325-339 ◽  
Author(s):  
Odo Diekmann
Keyword(s):  
Natural Selection ◽  
Mathematical Description ◽  
Evolutionary Dynamics ◽  
Biological Evolution ◽  
The Future ◽  
The Many

In this note we present an outsider's view on the mathematical description of long term biological evolution as driven by natural selection. It is an outlook to the future, more than an account of what has been achieved so far.

scholarly journals ACRE: Absolute concentration robustness exploration in module-based combinatorial networks

2017 ◽  
Vol 2 (1) ◽  
Author(s):  
Hiroyuki Kuwahara ◽  
Ramzan Umarov ◽  
Islam Almasri ◽  
Xin Gao
Keyword(s):  
Molecular Species ◽  
Molecular Mechanisms ◽  
Deep Understanding ◽  
Reaction Network ◽  
Software Tool ◽  
Structural Features ◽  
Biochemical Networks ◽  
Control Mechanisms ◽  
Absolute Concentration ◽  
Molecular Control

To engineer cells for industrial-scale application, a deep understanding of how to design molecular control mechanisms to tightly maintain functional stability under various fluctuations is crucial. Absolute concentration robustness (ACR) is a category of robustness in reaction network models in which the steady-state concentration of a molecular species is guaranteed to be invariant even with perturbations in the other molecular species in the network. Here, we introduce a software tool, absolute concentration robustness explorer (ACRE), which efficiently explores combinatorial biochemical networks for the ACR property. ACRE has a user-friendly interface, and it can facilitate efficient analysis of key structural features that guarantee the presence and the absence of the ACR property from combinatorial networks. Such analysis is expected to be useful in synthetic biology as it can increase our understanding of how to design molecular mechanisms to tightly control the concentration of molecular species. ACRE is freely available at https://github.com/ramzan1990/ACRE.

scholarly journals Inferring immunological control mechanisms from TKI dose alterations in CML patients

2019 ◽  
Author(s):  
Tom Hähnel ◽  
Christoph Baldow ◽  
Artur C. Fassoni ◽  
Joëlle Guilhot ◽  
François Guilhot ◽  
...  
Keyword(s):  
Immune Response ◽  
Kinase Inhibitors ◽  
Clinical Findings ◽  
Term Treatment ◽  
Control Mechanisms ◽  
Treatment Cessation ◽  
Long Term Treatment ◽  
Time Courses ◽  
The Individual

AbstractRecent clinical findings in chronic myeloid leukemia (CML) patients suggest that the risk of molecular recurrence after stopping tyrosine kinase inhibitors (TKI) treatment substantially depend on an individual, leukemia-specific immune response. However, it is still not possible to prospectively identify patients that will most likely remain in a long-term treatment free remission (TFR). Here, we use a mathematical model for CML, which explicitly includes an anti-leukemic (presumably immunological) effect and apply it to a set of patients (n=60) for whom BCR-ABL/ABL time courses had been quantified before and after TKI stop. We demonstrate that such a feedback control is conceptually necessary to explain long-term remission as observed in about half of the patients. Based on simulation results we classify the patient data sets into three different groups according to their predicted immune system configuration. While one class of patients requires a complete CML eradication to achieve TFR, other patients are able to control the leukemia after treatment cessation. Among them, we identified a third class of patients, which only maintains TFR if an optimal balance between leukemia abundance and immunological activation is achieved before treatment cessation. Further, we demonstrate that the immune response classification of the patients cannot be obtained solely from BCR-ABL measurements before treatment cessation. However, our results strongly suggest that changes in the BCR-ABL dynamics arising after system perturbations, such as TKI dose reduction, holds the information to predict the individual outcome after treatment cessation.

Personal Values Required for Ethical Best Practice during Intrapartum Care

2018 ◽  
Vol 20 (2) ◽  
Author(s):  
Jacobeth Mmabyala Louisa Malesela
Keyword(s):  
Nursing Education ◽  
Best Practice ◽  
Personal Values ◽  
Self Control ◽  
Intrapartum Care ◽  
Performance Reviews ◽  
Qualitative Research Design ◽  
Selection Processes ◽  
The Individual ◽  
Recruitment And Selection

Women bring into the birthing unit values which include preferences, concerns and expectations that are involved in decision-making during intrapartum care. When midwives fail to meet the women’s values, they experience such care as being inhumane and degrading, thus affecting the childbirth outcomes. The inhumane and degrading care includes a lack of sympathy and empathy, as well as a lack of attention to privacy and confidentiality. Midwives’ possession of the required personal values and the ability to integrate women’s values are vital to enhance ethical best practice during intrapartum care. The aim of the study was to explore and to describe the midwives’ personal values that are required for ethical best practice during intrapartum care. The birthing unit at a public hospital in the Gauteng province of South Africa formed the context of the study. A qualitative research design that was explorative, descriptive and contextual in nature was used. The following personal values emerged: (1) respect, trust and dignity; (2) justice, equality and fairness; (3) freedom of choice and autonomy; (4) integrity, honesty and consistency; (5) good character and personality; (6) self-control and rapport; and (7) open-mindedness and flexibility. The midwives’ personal values form a strong precursor that is crucial for ethical best practice during intrapartum care. The individual midwives, nursing education institutions and health facilities can use the study findings in areas such as reflective midwifery practice, the midwifery curriculum, recruitment and selection processes, and as part of key performance areas and indicators in performance reviews.

The Acceptance of Party Unity in Parliamentary Democracies

2017 ◽  
Author(s):  
David M. Willumsen
Keyword(s):  
Political Parties ◽  
Costs And Benefits ◽  
Parliamentary Democracies ◽  
Survey Questions ◽  
Ideal Policy ◽  
Central Argument ◽  
The Individual ◽  
Policy Incentives

The central argument of this book is that voting unity in European legislatures is not primarily the result of the ‘disciplining’ power of the leadership of parliamentary parties, but rather the result of a combination of ideological homogeneity through self-selection into political parties and the calculations of individual legislators about their own long-term benefits. Despite the central role of policy preferences in the subsequent behaviour of legislators, preferences at the level of the individual legislator have been almost entirely neglected in the study of parliaments and legislative behaviour. The book measures these using an until now under-utilized resource: parliamentary surveys. Building on these, the book develops measures of policy incentives of legislators to dissent from their parliamentary parties, and show that preference similarity amongst legislators explains a very substantial proportion of party unity, yet alone cannot explain all of it. Analysing the attitudes of legislators to the demands of party unity, and what drives these attitudes, the book argues that what explains the observed unity (beyond what preference similarity would explain) is the conscious acceptance by MPs that the long-term benefits of belonging to a united party (such as increased influence on legislation, lower transaction costs, and better chances of gaining office) outweigh the short-terms benefits of always voting for their ideal policy outcome. The book buttresses this argument through the analysis of both open-ended survey questions as well as survey questions on the costs and benefits of belonging to a political party in a legislature.

scholarly journals Long-Term Cocirculation of Two Strains of Pepino Mosaic Virus in Tomato Crops and Its Effect on Population Genetic Variability

2020 ◽  
Vol 110 (1) ◽  
pp. 49-57 ◽  
Author(s):  
C. Alcaide ◽  
M. P. Rabadán ◽  
M. Juárez ◽  
P. Gómez
Keyword(s):  
Genetic Variability ◽  
Mosaic Virus ◽  
Evolutionary Dynamics ◽  
Geographical Area ◽  
Viral Fitness ◽  
Mixed Infections ◽  
Supporting Evidence ◽  
Pepino Mosaic Virus ◽  
Nucleotide Variability

Mixed viral infections are common in plants, and the evolutionary dynamics of viral populations may differ depending on whether the infection is caused by single or multiple viral strains. However, comparative studies of single and mixed infections using viral populations in comparable agricultural and geographical locations are lacking. Here, we monitored the occurrence of pepino mosaic virus (PepMV) in tomato crops in two major tomato-producing areas in Murcia (southeastern Spain), supporting evidence showing that PepMV disease-affected plants had single infections of the Chilean 2 (CH2) strain in one area and the other area exhibited long-term (13 years) coexistence of the CH2 and European (EU) strains. We hypothesized that circulating strains of PepMV might be modulating the differentiation between them and shaping the evolutionary dynamics of PepMV populations. Our phylogenetic analysis of 106 CH2 isolates randomly selected from both areas showed a remarkable divergence between the CH2 isolates, with increased nucleotide variability in the geographical area where both strains cocirculate. Furthermore, the potential virus–virus interaction was studied further by constructing six full-length infectious CH2 clones from both areas, and assessing their viral fitness in the presence and absence of an EU-type isolate. All CH2 clones showed decreased fitness in mixed infections and although complete genome sequencing indicated a nucleotide divergence of those CH2 clones by area, the magnitude of the fitness response was irrespective of the CH2 origin. Overall, these results suggest that although agroecological cropping practices may be particularly important for explaining the evolutionary dynamics of PepMV in tomato crops, the cocirculation of both strains may have implications on the genetic variability of PepMV populations.

scholarly journals Title I: Modernizing Definitions and Programs Under the Administration on Aging

2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 714-715
Author(s):  
Marie Gualtieri
Keyword(s):  
Title I ◽  
Adult Population ◽  
Term Care ◽  
Older Americans ◽  
Aging Society ◽  
Program Adaptation ◽  
Older Americans Act ◽  
The Individual ◽  
Older Adult Population

Abstract The recent reauthorization of the Older Americans Act adds language and definitions to current issues facing the aging population. Specifically, Title I includes definitions related to program adaptation and coordination, workforce and long-term care issues, nutrition and social isolation, as well as family caregivers. Different from the last authorization, these definitions span beyond the individual experience to include other entities impacted by an aging society, such as the workforce and families. Overall, the Title I reauthorization seeks to modernize policy to reflect the current influx of the older adult population and its consequences.

scholarly journals Housing adaptations and housing accessibility problems among older adults with long-standing spinal cord injury

2020 ◽  
pp. 030802262097951
Author(s):  
Lizette Norin ◽  
Björn Slaug ◽  
Maria Haak ◽  
Susanne Iwarsson
Keyword(s):  
Older Adults ◽  
Spinal Cord ◽  
Spinal Cord Injuries ◽  
Occupational Performance ◽  
Environmental Barriers ◽  
Cord Injury ◽  
Long Term Follow Up ◽  
Societal Level ◽  
The Individual

Introduction Adults with spinal cord injuries are living longer than previously, and a majority are living in ordinary housing in the community. Housing accessibility is important for maintaining independent occupational performance for this population, but knowledge in this area is insufficient. We investigated housing adaptations and current accessibility problems among older adults with long-standing (>10 years) spinal cord injuries. Method Data from home visits among 122 older adults with spinal cord injuries in Sweden were used. Housing adaptations and environmental barriers were descriptively analysed. Findings Kitchens, entrances, and hygiene areas were common locations for housing adaptations and environmental barriers that generated accessibility problems. The most common adaptations were ramps, wheelchair-accessible stovetops, and ceiling-lifts. Wall-mounted cupboards and high shelves (kitchen), inaccessible storage areas (outside the dwelling), and a lack of grab bars (hygiene area) generated the most accessibility problems. Conclusion Despite housing adaptations, there are considerable accessibility problems in the dwellings of older adults with long-standing spinal cord injuries in Sweden, indicating that long-term follow-up of the housing situation of this population is necessary. Focusing on accessible housing as a prerequisite for occupational performance is at the core of occupational therapy, deserving attention on the individual as well as the societal level.

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