scholarly journals Emergence and diversification of a host-parasite RNA ecosystem through Darwinian evolution

2019 ◽  
Author(s):  
Taro Furubayashi ◽  
Kensuke Ueda ◽  
Yohsuke Bansho ◽  
Daisuke Motooka ◽  
Shota Nakamura ◽  
...  
Keyword(s):  
Darwinian Evolution ◽  
Prebiotic Evolution ◽  
Clonal Population ◽  
Replication Errors ◽  
Replication Experiment ◽  
Living Organisms ◽  
Host Parasite ◽  
First Time

AbstractIn the prebiotic evolution, molecular self-replicators are considered to develop into diverse, complex living organisms. The appearance of parasitic replicators is believed inevitable in this process. However, the role of parasitic replicators on prebiotic evolution remains elusive. Here, we demonstrated experimental coevolution of RNA self-replicators (host RNAs) and emerging parasitic replicators (parasitic RNAs) for the first time by using an RNA-protein replication system we had developed. During a long-term replication experiment, a clonal population of the host RNA turned into an evolving host-parasite ecosystem through the continuous emergence of new types of host and parasitic RNAs produced by replication errors. The diversified host and parasitic RNAs exhibited evolutionary arms-race dynamics. The parasitic RNA accumulated unique mutations that the host RNA had never acquired, thus adding a new genetic variation to the whole replicator ensemble. These results provide the first experimental evidence that the coevolutionary interplay between host-parasite molecules play a key role in generating diversity and complexity in prebiotic molecular evolution.

scholarly journals Emergence and diversification of a host-parasite RNA ecosystem through Darwinian evolution

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Taro Furubayashi ◽  
Kensuke Ueda ◽  
Yohsuke Bansho ◽  
Daisuke Motooka ◽  
Shota Nakamura ◽  
...  
Keyword(s):  
Arms Race ◽  
Darwinian Evolution ◽  
Prebiotic Evolution ◽  
Clonal Population ◽  
Replication Errors ◽  
Replication Experiment ◽  
Living Organisms ◽  
Host Parasite

In prebiotic evolution, molecular self-replicators are considered to develop into diverse, complex living organisms. The appearance of parasitic replicators is believed inevitable in this process. However, the role of parasitic replicators in prebiotic evolution remains elusive. Here, we demonstrated experimental coevolution of RNA self-replicators (host RNAs) and emerging parasitic replicators (parasitic RNAs) using an RNA-protein replication system we developed. During a long-term replication experiment, a clonal population of the host RNA turned into an evolving host-parasite ecosystem through the continuous emergence of new types of host and parasitic RNAs produced by replication errors. The host and parasitic RNAs diversified into at least two and three different lineages, respectively, and they exhibited evolutionary arms-race dynamics. The parasitic RNA accumulated unique mutations, thus adding a new genetic variation to the whole replicator ensemble. These results provide the first experimental evidence that the coevolutionary interplay between host-parasite molecules plays a key role in generating diversity and complexity in prebiotic molecular evolution.

scholarly journals Occurrence of L1014F and L1014S mutations in insecticide resistant Culex quinquefasciatus from filariasis endemic districts of West Bengal, India

2022 ◽  
Vol 16 (1) ◽  
pp. e0010000
Author(s):  
Priyanka Rai ◽  
Dhiraj Saha
Keyword(s):  
Culex Quinquefasciatus ◽  
West Bengal ◽  
Economic Status ◽  
Minor Role ◽  
Resistance Development ◽  
Vector Population ◽  
A Minor ◽  
First Time

Introduction Lymphatic filariasis causes long term morbidity and hampers the socio-economic status. Apart from the available treatments and medication, control of vector population Culex quinquefasciatus Say through the use of chemical insecticides is a widely applied strategy. However, the unrestrained application of these insecticides over many decades has led to resistance development in the vectors. Methods In order to determine the insecticide susceptibility/resistance status of Cx. quinquefasciatus from two filariasis endemic districts of West Bengal, India, wild mosquito populations were collected and assayed against six different insecticides and presence of L1014F; L1014S kdr mutations in the voltage-gated sodium channel gene was also screened along with the use of synergists to evaluate the role of major detoxifying enzymes in resistance development. Results The collected mosquito populations showed severe resistance to insecticides and the two synergists used–PBO (piperonyl butoxide) and TPP (triphenyl phosphate), were unable to restore the susceptibility status of the vector thereupon pointing towards a minor role of metabolic enzymes. kdr mutations were present in the studied populations in varying percent with higher L1014F frequency indicating its association with the observed resistance to pyrethroids and DDT. This study reports L1014S mutation in Cx. quinquefasciatus for the first time.

scholarly journals Dynamics of intravital concentration of amino acid metabolites in human brain in post-traumatic period

2019 ◽  
Vol 484 (2) ◽  
pp. 238-242
Author(s):  
N. A. Semenova ◽  
P. E. Menshchikov ◽  
A. V. Manzhurtsev ◽  
M. V. Ublinskiy ◽  
T. A. Akhadov ◽  
...  
Keyword(s):  
Traumatic Brain Injury ◽  
Amino Acid ◽  
Human Brain ◽  
Leading Role ◽  
Acid Metabolites ◽  
Post Traumatic ◽  
First Time

Intracellular concentrations of N acetyaspartate (NAA), aspartate (Asp) and glutamate (Glu) were determined for the first time in human brain in vivo, and the effect of severe traumatic brain injury on NAA synthesis in acute and late post-traumatic period was investigated. In MRI‑negative frontal lobes one day after injury Asp and Glu levels were found to decrease by 45 and 35%, respectively, while NAA level decreased by only 16%. A negative correlation between NAA concentration and the ratio of Asp/Glu concentrations was found. In the long-term period, Glu level returned to normal, Asp level remained below normal by 60%, NAA level was reduced by 65% relative to normal, and Asp/Glu ratio significantly decreased. The obtained results revealed leading role of the neuronal aspartate-malate shuttle in violation of NAA synthesis.

Too resilient for anyone’s good

Kybernetes ◽  
2019 ◽  
Vol 48 (4) ◽  
pp. 751-768 ◽  
Author(s):  
Lance Nizami
Keyword(s):  
Auditory Stimulus ◽  
Design Methodology ◽  
Detection Thresholds ◽  
Content Type ◽  
Infant Vision ◽  
Efficacious Treatment ◽  
Stimulus Detection ◽  
First Time

Purpose This study aims to examine the observer’s role in “infant psychophysics”. Infant psychophysics was developed because the diagnosis of perceptual deficits should be done as early in a patient’s life as possible, to provide efficacious treatment and thereby reduce potential long-term costs. Infants, however, cannot report their perceptions. Hence, the intensity of a stimulus at which the infant can detect it, the “threshold”, must be inferred from the infant’s behavior, as judged by observers (watchers). But whose abilities are actually being inferred? The answer affects all behavior-based conclusions about infants’ perceptions, including the well-proselytized notion that auditory stimulus-detection thresholds improve rapidly during infancy. Design/methodology/approach In total, 55 years of infant psychophysics is scrutinized, starting with seminal studies in infant vision, followed by the studies that they inspired in infant hearing. Findings The inferred stimulus-detection thresholds are those of the infant-plus-watcher and, more broadly, the entire laboratory. The thresholds are therefore tenuous, because infants’ actions may differ with stimulus intensity; expressiveness may differ between infants; different watchers may judge infants differently; etc. Particularly, the watcher’s ability to “read” the infant may improve with the infant’s age, confounding any interpretation of perceptual maturation. Further, the infant’s gaze duration, an assumed cue to stimulus detection, may lengthen or shorten nonlinearly with infant age. Research limitations/implications Infant psychophysics investigators have neglected the role of the observer, resulting in an accumulation of data that requires substantial re-interpretation. Altogether, infant psychophysics has proven far too resilient for its own good. Originality/value Infant psychophysics is examined for the first time through second-order cybernetics. The approach reveals serious unresolved issues.

scholarly journals Scribing Method for Carbon Perovskite Solar Modules

Energies ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1589 ◽  
Author(s):  
Simone M. P. Meroni ◽  
Katherine E. A. Hooper ◽  
Tom Dunlop ◽  
Jenny A. Baker ◽  
David Worsley ◽  
...  
Keyword(s):  
Screen Printing ◽  
Fill Factor ◽  
Transparent Electrode ◽  
Perovskite Solar Cell ◽  
Metal Contacts ◽  
Good Efficiency ◽  
Long Term Stability ◽  
First Time

The fully printable carbon triple-mesoscopic perovskite solar cell (C-PSC) has already demonstrated good efficiency and long-term stability, opening the possibility of lab-to-fab transition. Modules based on C-PSC architecture have been reported and, at present, are achieved through the accurate registration of each of the patterned layers using screen-printing. Modules based on this approach were reported with geometric fill factor (g-FF) as high as 70%. Another approach to create the interconnects, the so-called scribing method, was reported to achieve more than 90% g-FF for architectures based on evaporated metal contacts, i.e., without a carbon counter electrode. Here, for the first time, we adopt the scribing method to selectively remove materials within a C-PSC. This approach allowed a deep and selective scribe to open an aperture from the transparent electrode through all the layers, including the blocking layer, enabling a direct contact between the electrodes in the interconnects. In this work, a systematic study of the interconnection area between cells is discussed, showing the key role of the FTO/carbon contact. Furthermore, a module on 10 × 10 cm2 substrate with the optimised design showing efficiency over 10% is also demonstrated.

Long-term unemployment

2020 ◽  
Vol 47 (4) ◽  
pp. 713-727
Author(s):  
Emmanuel Apergis ◽  
Nicholas Apergis
Keyword(s):  
Working Environment ◽  
Employment Relations ◽  
Content Type ◽  
Different Types ◽  
The Uk ◽  
First Time ◽  
Robustness Check ◽  
Modelling Approach

PurposeThis paper empirically explores the role of skill losses during unemployment behind firms' behaviour in interviewing long-term unemployedDesign/methodology/approachThe analysis makes use of the Work Employment Relations Survey in the UK, while it applies a panel probit modelling approach to estimate the empirical findings.FindingsThe findings document that skill losses during long-term unemployment reduce the likelihood of an interview, while they emphasize the need for certain policies that could compensate for this deterioration of skills. For robustness check, the estimation strategy survives the examination of the same predictors under different types of the working environment.Originality/valueThe original values of the work 1 combines for the first time both duration and technology as predictors of interview probability. Until now, the independent variables were used to test whether an individual has managed to exit unemployment, thus skipping the step of the interview process.

Causes and prerequisites of the occupation of Luhansk and Donetsk regions: empirical analysis of territories (on the basis of indicators of the democratization index “Freedom in the World 2020”)

2021 ◽  
pp. 43-48
Author(s):  
M. Vehesh ◽  
R. Kopolovets
Keyword(s):  
Armed Forces ◽  
Political Regime ◽  
Military Conflict ◽  
Democratic Development ◽  
Occupied Territories ◽  
The Russian Federation ◽  
Hybrid War ◽  
First Time

Summary. The article examines the main reasons and preconditions for the occupation of certain regions in eastern Ukraine. The influence and role of Russia in this military conflict are analyzed, and for the first time an empirical (applied) analysis of the democratization index in the temporarily occupied territories is carried out. Russia’s aggressive policy in eastern Ukraine is part of a “hybrid” war against Ukraine that began in early 2014 with the occupation of the Autonomous Republic of Crimea. With the support of Russia, the so-called “Donetsk and Luhansk” people’s republics were created in eastern Ukraine. In essence, these are occupation military administrations that number more than 30,000 people, including regular troops and instructors of the armed forces of the Russian Federation. These are well-armed military formations, the number and combat capabilities of which are not inferior to the armies of individual European countries. In the temporarily occupied territories there is a total political and ideological “Russification”, the purpose of which is the alienation and further isolation of these territories from official Kyiv. It should be noted that the hostilities, which have been going on for the sixth year, pose serious economic, political, legal, and geopolitical problems on Ukraine’s path to consolidating the democratic regime and integrating with the European community. The change of political regime in 2013 in Ukraine opened up prospects for the consolidation of national identity and the restoration of the course of Euro-Atlantic integration, which was usually not accepted by official Moscow and personally by President Putin. It should be clearly understood that the war in Donbass, provoked by Russia, is the result of a systematic and long-term policy of Russia towards Ukraine as a country with a favorable geopolitical location and a kind of bridge between Europe and Russia. The article pays special attention to the theoretical and applied analysis of democratic development in Donbass. It should be noted that from 2020 “Freedom House” will start monitoring the territory and accordingly provide quantitative data on the democratization index with the appropriate analytical base and forecasts.

scholarly journals Triage: line or nets? Early intervention and the youth justice system

2014 ◽  
Vol 13 (4) ◽  
pp. 147-160 ◽  
Author(s):  
Sarah Soppitt ◽  
Adele Irving
Keyword(s):  
Restorative Justice ◽  
Justice System ◽  
Design Methodology ◽  
Qualitative Data ◽  
Youth Justice ◽  
Content Type ◽  
The Impact ◽  
First Time

Purpose – The purpose of this paper is to present a discussion of the value of early diversion schemes, underpinned by the principles of restorative justice (RJ), for First Time Entrants (FTEs) into the criminal justice system (CJS). Design/methodology/approach – The paper focuses specifically on the findings of a 12-month study into the introduction of “Triage” by one Youth Offending Team (YOT) in the northeast of England. Findings – Re-offending data suggested that Triage is more effective in reducing re-offending than conventional justice practices, due to the restorative nature of the scheme. However, the qualitative data raised a number of issues, particularly relating to problems of “net-widening” and the impact of recording processes on young people's desistance, as well as the role of victim engagement in the process. These issues could undermine the long-term effectiveness of Triage and its successful application within other youth justice contexts. Originality/value – The paper aims to contribute further understanding regarding the impacts of RJ practices on reducing re-offending compared to traditional processes, and in particular, consider the role of implementation issues in the production of outcomes and impacts.

scholarly journals Extinction-resistant attention to long-term conditioned threat is indexed by selective visuocortical alpha suppression in humans

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Christian Panitz ◽  
Andreas Keil ◽  
Erik M. Mueller
Keyword(s):  
Visual Attention ◽  
Time Windows ◽  
Alpha Power ◽  
Physiological Measures ◽  
Time Frequency ◽  
Long Term Stability ◽  
Electrophysiological Studies ◽  
First Time

Abstract Previous electrophysiological studies in humans have shown rapid modulations of visual attention after conditioned threat vs. safety cues (<500 ms post-stimulus), but it is unknown whether this attentional prioritization is sustained throughout later time windows and whether it is robust to extinction. To investigate sustained visual attention, we assessed visuocortical alpha suppression in response to conditioned and extinguished threat. We reanalysed data from N = 87 male participants that had shown successful long-term threat conditioning and extinction in self reports and physiological measures in a two-day conditioning paradigm. The current EEG time-frequency analyses on recall test data on Day 2 revealed that previously threat-conditioned vs. safety cues evoked stronger occipital alpha power suppression from 600 to 1200 ms. Notably, this suppression was resistant to previous extinction. The present study showed for the first time that threat conditioning enhances sustained modulation of visuocortical attention to threat in the long term. Long-term stability and extinction resistance of alpha suppression suggest a crucial role of visuocortical attention mechanisms in the maintenance of learned fears.

scholarly journals Midkine Is a Novel Regulator of Amphetamine-Induced Striatal Gliosis and Cognitive Impairment: Evidence for a Stimulus-Dependent Regulation of Neuroinflammation by Midkine

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Marta Vicente-Rodríguez ◽  
Rosalía Fernández-Calle ◽  
Esther Gramage ◽  
Carmen Pérez-García ◽  
María P. Ramos ◽  
...  
Keyword(s):  
Brain Area ◽  
Memory Task ◽  
Long Term Effects ◽  
Y Maze ◽  
Amphetamine Treatment ◽  
Microglial Response ◽  
First Time ◽  
The Brain

Midkine (MK) is a cytokine that modulates amphetamine-induced striatal astrogliosis, suggesting a possible role of MK in neuroinflammation induced by amphetamine. To test this hypothesis, we studied astrogliosis and microglial response induced by amphetamine (10 mg/kg i.p. four times, every 2 h) in different brain areas of MK−/− mice and wild type (WT) mice. We found that amphetamine-induced microgliosis and astrocytosis are enhanced in the striatum of MK−/− mice in a region-specific manner. Surprisingly, LPS-induced astrogliosis in the striatum was blocked in MK−/− mice. Since striatal neuroinflammation induced by amphetamine-type stimulants correlates with the cognitive deficits induced by these drugs, we also tested the long-term effects of periadolescent amphetamine treatment (3 mg/kg i.p. daily for 10 days) in a memory task in MK−/− and WT mice. Significant deficits in the Y-maze test were only observed in amphetamine-pretreated MK−/− mice. The data demonstrate for the first time that MK is a novel modulator of neuroinflammation depending on the inflammatory stimulus and the brain area considered. The data indicate that MK limits amphetamine-induced striatal neuroinflammation. In addition, our data demonstrate that periadolescent amphetamine treatment in mice results in transient disruption of learning and memory processes in absence of endogenous MK.

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