scholarly journals Ongoing resolution of duplicate gene functions shapes the diversification of a metabolic network

eLife ◽  
2016 ◽  
Vol 5 ◽  
Author(s):  
Meihua Christina Kuang ◽  
Paul D Hutchins ◽  
Jason D Russell ◽  
Joshua J Coon ◽  
Chris Todd Hittinger
Keyword(s):  
Control Systems ◽  
Yeast Species ◽  
Duplicate Gene ◽  
Functional Differentiation ◽  
Network Architectures ◽  
Evolutionary Mechanisms ◽  
Yeast Saccharomyces Cerevisiae ◽  
Regulation Of Metabolism ◽  
Metabolic Strategies

The evolutionary mechanisms leading to duplicate gene retention are well understood, but the long-term impacts of paralog differentiation on the regulation of metabolism remain underappreciated. Here we experimentally dissect the functions of two pairs of ancient paralogs of the GALactose sugar utilization network in two yeast species. We show that the Saccharomyces uvarum network is more active, even as over-induction is prevented by a second co-repressor that the model yeast Saccharomyces cerevisiae lacks. Surprisingly, removal of this repression system leads to a strong growth arrest, likely due to overly rapid galactose catabolism and metabolic overload. Alternative sugars, such as fructose, circumvent metabolic control systems and exacerbate this phenotype. We further show that S. cerevisiae experiences homologous metabolic constraints that are subtler due to how the paralogs have diversified. These results show how the functional differentiation of paralogs continues to shape regulatory network architectures and metabolic strategies long after initial preservation.

Men's and Women's Mating Preferences: Distinct Evolutionary Mechanisms?

2002 ◽  
Vol 11 (3) ◽  
pp. 88-93 ◽  
Author(s):  
Lynn Carol Miller ◽  
Anila Putcha-Bhagavatula ◽  
William C. Pedersen
Keyword(s):  
Sexual Functioning ◽  
Large Female ◽  
Detailed Knowledge ◽  
Short Term ◽  
Evolutionary Mechanisms ◽  
Men And Women ◽  
Mating Preferences ◽  
Chemical Mechanisms ◽  
Species Comparisons

Have men and women evolved sex-distinct mating preferences for short-term and long-term mating, as postulated by some evolutionary theorists? Direct tests of assumptions, consideration of confounds with gender, and examination of the same variables for both sexes suggest men and women are remarkably similar. Furthermore, cross-species comparisons indicate that humans do not evidence mating mechanisms indicative of short-term mating (e.g., large female sexual skins, large testicles). Understanding human variability in mating preferences is apt to involve more detailed knowledge of the links between these preferences and biological and chemical mechanisms associated with sexual motivation, sexual arousal, and sexual functioning.

Machine Learning for Neurodegenerative Disorder Diagnosis — Survey of Practices and Launch of Benchmark Dataset

2018 ◽  
Vol 27 (03) ◽  
pp. 1850011 ◽  
Author(s):  
Athanasios Tagaris ◽  
Dimitrios Kollias ◽  
Andreas Stafylopatis ◽  
Georgios Tagaris ◽  
Stefanos Kollias
Keyword(s):  
Machine Learning ◽  
Neurodegenerative Disorder ◽  
Developed Countries ◽  
Machine Learning Techniques ◽  
Network Architectures ◽  
Imaging Data ◽  
Learning Techniques ◽  
Medical Examinations

Neurodegenerative disorders, such as Alzheimer’s and Parkinson’s, constitute a major factor in long-term disability and are becoming more and more a serious concern in developed countries. As there are, at present, no effective therapies, early diagnosis along with avoidance of misdiagnosis seem to be critical in ensuring a good quality of life for patients. In this sense, the adoption of computer-aided-diagnosis tools can offer significant assistance to clinicians. In the present paper, we provide in the first place a comprehensive recording of medical examinations relevant to those disorders. Then, a review is conducted concerning the use of Machine Learning techniques in supporting diagnosis of neurodegenerative diseases, with reference to at times used medical datasets. Special attention has been given to the field of Deep Learning. In addition to that, we communicate the launch of a newly created dataset for Parkinson’s disease, containing epidemiological, clinical and imaging data, which will be publicly available to researchers for benchmarking purposes. To assess the potential of the new dataset, an experimental study in Parkinson’s diagnosis is carried out, based on state-of-the-art Deep Neural Network architectures and yielding very promising accuracy results.

scholarly journals FORMALIZATION OF CONTROL MECHANISMS: THE CASE OF SMALL COMPANIES

2020 ◽  
Vol 6 (7) ◽  
pp. 144-155
Author(s):  
Andriamasimanana Origene Harizofinoana ◽  
Andriamasimanana Origene Olivier
Keyword(s):  
Control System ◽  
Control Systems ◽  
Great Difficulty ◽  
Statistical Analyses ◽  
Control Mechanisms ◽  
Small Companies ◽  
Management Tools ◽  
Modern Management

Control mechanisms are the major problem for small companies such as VSEs and SMEs today. A hypothetical-deductive approach was adopted in this research to demonstrate that the more the size of companies changes, the more the degree of formalization of control systems increases. The study based on the case of 25 Malagasy companies through statistical analyses confirmed this hypothesis. VSEs still have great difficulty in implementing a control system that meets their long-term needs due to lack of resources and the use of modern management tools linked to control systems also varies according to their size. Innovation in this sense is necessary to enable small companies to better control their activities and to ensure a very good performance.

scholarly journals Induction of the synthesis of an additional family of long-chain dolichols in the yeast Saccharomyces cerevisiae. Effect of starvation and ageing.

2002 ◽  
Vol 49 (3) ◽  
pp. 781-787 ◽  
Author(s):  
Anna Szkopinska ◽  
Ewa Swiezewska ◽  
Joanna Rytka
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Stationary Phase ◽  
Yeast Cells ◽  
Logarithmic Phase ◽  
Cellular Membranes ◽  
Yeast Saccharomyces Cerevisiae ◽  
Chemical Changes ◽  
Physico Chemical ◽  
Long Chain

The yeast Saccharomyces cerevisiae strain W303 synthesizes in the early logarithmic phase of growth dolichols of 14-18 isoprene residues. The analysis of the polyisoprenoids present in the stationary phase revealed an additional family which proved to be also dolichols but of 19-24 isoprene residues, constituting 39% of the total dolichols. The transfer of early logarithmic phase cells to a starvation medium lacking glucose or nitrogen resulted in the synthesis of the longer chain dolichols. The additional family of dolichols represented 13.8% and 10.3% of total dolichols in the glucose and nitrogen deficient media, respectively. The level of dolichols in yeast cells increased with the age of the cultures. Since both families of dolichols are present in stationary phase cells we postulate that the longer chain dolichols may be responsible for the physico-chemical changes in cellular membranes allowing yeast cells to adapt to nutrient deficient conditions to maintain long-term viability.

scholarly journals ANALYSIS OF THE COMPETITIVE ADVANTAGE SUSTAINABILITY FACTORS BASED ON THE KEY COMPETENCIES OF AN ELECTRICAL ENGINEERING ENTERPRISE

2020 ◽  
pp. 134-141
Author(s):  
S. B. Moiseev
Keyword(s):  
Competitive Advantage ◽  
Organizational Development ◽  
Competitive Advantages ◽  
Sustainable Competitive Advantage ◽  
Evolutionary Mechanisms ◽  
Industrial Companies ◽  
Key Competencies ◽  
Methodological Approaches ◽  
Engineering Enterprise

The factors influencing the possibility of the theory of key competencies adaptation within the traditional ideas of the resource approach to ensure the long-term competitiveness of companies have been considered. For this purpose, the review of features of application of key competencies during the formation of strategies of the industrial companies of mature sectors of industries has been carried out, in which thanks to action of evolutionary mechanisms of technological and organizational development there are objective preconditions for creation of steady competitive advantages on their basis. The necessity of development of methodological approaches to the formation of company’s competitive strategy in the sector of electrical production based on the formation of organizational-economic mechanism of adaptation to external influences and internal changes to manage the development of key competencies as factors of sustainable competitive advantage in the future and the formation of long-term effective business development model of the enterprise, has been substantiated.

Paradoxical tensions of the COVID-19 pandemic: a paradox theory perspective on the role of management control systems in helping organizations survive crises

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ralph Kober ◽  
Paul J. Thambar
Keyword(s):  
Control Systems ◽  
Management Control ◽  
Management Control Systems ◽  
Short Term ◽  
Content Type ◽  
Strategic Objectives ◽  
Paradox Theory ◽  
Practical Implications

PurposeThis paper presents paradox theory as a useful theoretical lens for researchers exploring crises such as coronavirus disease 2019 (COVID-19). The authors argue that paradox theory, which emphasizes a “both/and” as opposed to an “either/or” approach, is ideally suited for management control systems (MCS) research on crises.Design/methodology/approachThe authors adopt a revelatory case approach to provide empirical examples of the insights that paradox theory can provide.FindingsThis paper highlights how MCS can be used to simultaneously manage short-term/operational and long-term/strategic objectives to navigate a crisis. Furthermore, it highlights how MCS can be mobilized during crises to identify and embrace opportunities.Practical implicationsThis paper illustrates the importance of MCS focusing on not just the short-term, but also the long-term, and managing multiple objectives in assisting organizations to survive crisis.Originality/valueThis paper highlights the benefits of using paradox theory to understand the role of MCS in helping organizations manage crises and to use a crisis as a source of opportunity.

scholarly journals Building mountain biodiversity: Geological and evolutionary processes

Science ◽  
2019 ◽  
Vol 365 (6458) ◽  
pp. 1114-1119 ◽  
Author(s):  
Carsten Rahbek ◽  
Michael K. Borregaard ◽  
Alexandre Antonelli ◽  
Robert K. Colwell ◽  
Ben G. Holt ◽  
...  
Keyword(s):  
Regional Climate ◽  
Ecological Processes ◽  
Evolutionary Mechanisms ◽  
Deep Time ◽  
Nutrient Runoff ◽  
Tropical Mountains ◽  
Rock Types ◽  
Dynamic Landscapes ◽  
Speciation Rates

Mountain regions are unusually biodiverse, with rich aggregations of small-ranged species that form centers of endemism. Mountains play an array of roles for Earth’s biodiversity and affect neighboring lowlands through biotic interchange, changes in regional climate, and nutrient runoff. The high biodiversity of certain mountains reflects the interplay of multiple evolutionary mechanisms: enhanced speciation rates with distinct opportunities for coexistence and persistence of lineages, shaped by long-term climatic changes interacting with topographically dynamic landscapes. High diversity in most tropical mountains is tightly linked to bedrock geology—notably, areas comprising mafic and ultramafic lithologies, rock types rich in magnesium and poor in phosphate that present special requirements for plant physiology. Mountain biodiversity bears the signature of deep-time evolutionary and ecological processes, a history well worth preserving.

The Need for Strategic Planning for Nuclear Power Plant I&C Upgrades

2002 ◽  
Author(s):  
J. Douglas Hill ◽  
Paul Moore
Keyword(s):  
Strategic Planning ◽  
Control Systems ◽  
Digital Technology ◽  
Nuclear Power ◽  
Power Plants ◽  
Short Term ◽  
Nuclear Plants ◽  
And Control ◽  
Plant Control

Nuclear power plants rely on Instrumentation and Control (I&C) systems for control, monitoring and protection of the plant. The original, analog designs used in most nuclear plants have become or soon will be obsolete, forcing plants to turn to digital technology. Many factors affect the design of replacement equipment, including long-term and short-term economics, regulatory issues, and the way the plant operates on a day-to-day basis. The first step to all modernization projects should involve strategic planning, to ensure that the overall long and short-term goals of the plant are met. Strategic planning starts with a thorough evaluation of the existing plant control systems, the available options, and the benefits and consequences of these options.

Functional differentiation of nitrate-reducing isolates regulated by long-term fertilization in a rice paddy soil

2020 ◽  
pp. 1-9
Author(s):  
Xing Chen ◽  
Yi Liu ◽  
Chunmei Liu ◽  
Wenzhao Zhang ◽  
Hongling Qin ◽  
...  
Keyword(s):  
Growth Medium ◽  
Normal Growth ◽  
Rice Paddy ◽  
Functional Differentiation ◽  
Fertilizer Treatment ◽  
Potassium Fertilizer ◽  
Nutritional Conditions ◽  
Nitrate Reducers ◽  
Nitrite Production

Fertilization can cause obvious shifts in nitrate-reducing community composition in agricultural ecosystems; however, little is known about the behaviors and functional characters of isolated nitrate reducers adapted to a specific environment. In this study, 849 nitrate-reducing bacteria were isolated from various fertilization treatments in a long-term paddy field experiment; the isolates were further characterized in functions with both culture-dependent and independent methodologies. The results showed that CK (no fertilizer) treatment had four genera with even relative abundance, whereas the other three treatments had their own predominant genera with Chromobacterium in nitrogen (N) fertilizer, Serratia in NPK (nitrogen, phosphorus, and potassium fertilizer) and Enterobacter in NPKC treatment (NPK plus rice straw). The isolates of Serratia and Enterobacter grew faster and produced significantly more nitrites than those of Chromobacterium and Burkholderia in the normal growth medium, suggesting that the dominant isolates from nutrient-rich environment, such as NPK and NPKC treatments, are better adapted to high nutritional conditions. On the contrary, the strains of Chromobacterium and Burkholderia possessed stronger nitrite production ability in comparison with the isolates of Serratia and Enterobacter in the diluted growth medium, indicating that the selected isolates from CK and N treatments have the capability to develop under nutrient-limiting conditions. Our results indicated that the behaviors and functions of nitrate reducers appears to be important in adapting to their dwelling habitats.

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