scholarly journals Ageing via sexual perception is a by-product of male adaptive plasticity inDrosophila melanogaster

2021 ◽  
Author(s):  
Quentin Corbel ◽  
Manuel Serra ◽  
Roberto García-Roa ◽  
Pau Carazo
Keyword(s):  
Adaptive Plasticity ◽  
Lifetime Reproductive Success ◽  
Environmental Cues ◽  
Average Increase ◽  
Adaptive Responses ◽  
Short Term ◽  
Wide Range ◽  
Sexual Perception ◽  
Opportunity For Selection

ABSTRACTSensory perception of environmental cues can dramatically modulate ageing across distant taxa. For example, maleDrosophila melanogasterage faster if they perceive female cues but fail to mate (ageing via sexual perception). This finding has been a breakthrough for our understanding of the mechanisms of ageing, yet we ignore how and why such responses have evolved. Here, we usedD. melanogasterto ask whether ageing via sexual perception may be a by-product of plastic adaptive responses to female cues, and found that while long-term sexual perception leads to reproductive costs, short-term perception increases male lifetime reproductive success in a competitive environment. Simulations under a wide range of socio-sexual and demographic scenario suggest that such plasticity as a response to sexual perception might be a widespread strategy in nature. Finally, we show that sexual perception can significantly magnify sexual selection (15-27% average increase in the opportunity for selection).

scholarly journals Perception of investing in crypto in India using UTAUT model

2021 ◽  
Vol 9 (10) ◽  
pp. 1396-1400
Author(s):  
Vidhi Shah
Keyword(s):  
Indian Population ◽  
Social Benefits ◽  
Short Term ◽  
Perceived Safety ◽  
Utaut Model ◽  
Performance Expectancy ◽  
Wide Range ◽  
Effort Expectancy ◽  
Do So

Abstract: This research was conducted to gather data and understand the perception what the Indian population holds when it comes to investing in cryptocurrency. To do so, a survey was designed using the UTAUT model and was circulated by the means of google forms. A wide range of parameters were considered to avail the maximum possible accuracy for the data collected. Parameters like, the ease of investing crypto, short term and long term benefits, monetary benefits, social benefits were considered. All of these parameters were supposed to be answered on a scale of 5. After collecting all the data, the results were analyzed and evaluated using which the hypothesis made were proved. Keywords: Cryptocurrency, UTAUT, performance expectancy, effort expectancy, perceived monetary benefits, perceived safety, social influence, adoption intension.

scholarly journals Observations of rapid-fire event tremor at Lascar volcano, Chile

1996 ◽  
Vol 39 (2) ◽  
Author(s):  
G. Asch ◽  
K. Wylegalla ◽  
M. Hellweg ◽  
D. Seidl ◽  
H. Rademacher
Keyword(s):  
Fractal Structure ◽  
Seismic Station ◽  
Active Volcano ◽  
Short Term ◽  
Fire Event ◽  
Local Seismicity ◽  
Short Period ◽  
Wide Range ◽  
Lascar Volcano

During the Proyecto de Investigaciòn Sismològica de la Cordillera Occidental (PISCO '94) in the Atacama desert of Northern Chile, a continuously recording broadband seismic station was installed to the NW of the currently active volcano, Lascar. For the month of April, 1994, an additional network of three, short period, three-component stations was deployed around the volcano to help discriminate its seismic signals from other local seismicity. During the deployment, the volcanic activity at Lascar appeared to be limited mainly to the emission of steam and SO2. Tremor from Lascar is a random, «rapid-fire» series of events with a wide range of amplitudes and a quasi-fractal structure. The tremor is generated by an ensemble of independent elementary sources clustered in the volcanic edifice. In the short-term, the excitation of the sources fluctuates strongly, while the long-term power spectrum is very stationary.

scholarly journals Prevalence and prognostic implication of iron deficiency and anaemia in patients with severe aortic stenosis

Open Heart ◽  
2018 ◽  
Vol 5 (2) ◽  
pp. e000901
Author(s):  
Anette Borger Kvaslerud ◽  
Amjad Iqbal Hussain ◽  
Andreas Auensen ◽  
Thor Ueland ◽  
Annika E Michelsen ◽  
...  
Keyword(s):  
Iron Deficiency ◽  
Aortic Stenosis ◽  
Severe Aortic Stenosis ◽  
Iron Status ◽  
Transferrin Saturation ◽  
Short Term ◽  
Prognostic Implication ◽  
Wide Range ◽  
One Year

ObjectiveThe aim of this study was to evaluate the prevalence and prognostic implication of iron deficiency (ID) and anaemia in patients with severe aortic stenosis (AS).MethodsIn an observational study of consecutive patients referred for aortic valve replacement (AVR), we assessed a wide range of biomarkers of iron status, including the definition of ID commonly applied in patients with chronic heart failure (ferritin <100 µg/L or ferritin 100–299 µg/L with a transferrin saturation <20%). The endpoints were short-term (one-year) and long-term (median 4.7 years, IQR: 3.8–5.5) mortality and major adverse cardiovascular events (MACE) within the first year after inclusion.Results464 patients were included in this substudy. 91 patients (20%) received conservative treatment and 373 patients (80%) received AVR. ID was detected in 246 patients (53%). 94 patients (20%) had anaemia. Patients with ID had an overall worse clinical profile than patients without ID. During follow-up, 129 patients (28%) died. Neither ID as defined above, soluble transferrin receptor nor hepcidin were associated with short-term or long-term mortality or MACE independent on treatment allocation. Anaemia was associated with one-year mortality in conservatively treated patients.ConclusionsID and anaemia are prevalent in patients with severe AS. In our cohort, ID did not provide independent prognostic information on top of conventional risk factors. More studies are required to determine how to correctly diagnose ID in patients with AS.Trial registration numberNCT01794832.

scholarly journals Novel FTLRNN with Gamma Memory for Short-Term and Long-Term Predictions of Chaotic Time Series

2009 ◽  
Vol 2009 ◽  
pp. 1-21
Author(s):  
Sanjay L. Badjate ◽  
Sanjay V. Dudul
Keyword(s):  
Neural Network ◽  
Time Series ◽  
Mean Squared Error ◽  
Chaotic Time Series ◽  
Nonstationary Time Series ◽  
Medium Term ◽  
Short Term ◽  
Squared Error ◽  
Wide Range

Multistep ahead prediction of a chaotic time series is a difficult task that has attracted increasing interest in the recent years. The interest in this work is the development of nonlinear neural network models for the purpose of building multistep chaotic time series prediction. In the literature there is a wide range of different approaches but their success depends on the predicting performance of the individual methods. Also the most popular neural models are based on the statistical and traditional feed forward neural networks. But it is seen that this kind of neural model may present some disadvantages when long-term prediction is required. In this paper focused time-lagged recurrent neural network (FTLRNN) model with gamma memory is developed for different prediction horizons. It is observed that this predictor performs remarkably well for short-term predictions as well as medium-term predictions. For coupled partial differential equations generated chaotic time series such as Mackey Glass and Duffing, FTLRNN-based predictor performs consistently well for different depths of predictions ranging from short term to long term, with only slight deterioration after k is increased beyond 50. For real-world highly complex and nonstationary time series like Sunspots and Laser, though the proposed predictor does perform reasonably for short term and medium-term predictions, its prediction ability drops for long term ahead prediction. However, still this is the best possible prediction results considering the facts that these are nonstationary time series. As a matter of fact, no other NN configuration can match the performance of FTLRNN model. The authors experimented the performance of this FTLRNN model on predicting the dynamic behavior of typical Chaotic Mackey-Glass time series, Duffing time series, and two real-time chaotic time series such as monthly sunspots and laser. Static multi layer perceptron (MLP) model is also attempted and compared against the proposed model on the performance measures like mean squared error (MSE), Normalized mean squared error (NMSE), and Correlation Coefficient (r). The standard back-propagation algorithm with momentum term has been used for both the models.

scholarly journals The Effectiveness of Employment Vouchers: A Simple Approach

2000 ◽  
Vol 1 (4) ◽  
pp. 385-419 ◽  
Author(s):  
J. Michael Orszag ◽  
Dennis J. Snower
Keyword(s):  
Optimal Policy ◽  
Policy Design ◽  
Unemployment Benefits ◽  
Government Budget ◽  
Long Term Effects ◽  
Short Term ◽  
Wide Range ◽  
The Government ◽  
Hiring And Firing

Abstract This paper explores the optimal design of subsidies for hiring unemployed workers (`employment vouchers' for short) in the context of a simple dynamic model of the labour market. Focusing on the short-term and long-term effects of the vouchers on employment and unemployment, the analysis shows how the optimal policy depends on the rates of hiring and firing, and on the problems of displacement and deadweight. It also examines the roles of the government budget constraint and of the level of unemployment benefits in optimal policy design. We calibrate the model and evaluate the effectiveness of employment vouchers in reducing unemployment for a wide range of feasible parameters.

N-Acetylcysteine’s Attenuation of Fatigue After Repeated Bouts of Intermittent Exercise: Practical Implications for Tournament Situations

2011 ◽  
Vol 21 (6) ◽  
pp. 451-461 ◽  
Author(s):  
James N. Cobley ◽  
Chris McGlory ◽  
James P. Morton ◽  
Graeme L. Close
Keyword(s):  
Side Effects ◽  
Muscle Fatigue ◽  
Intermittent Exercise ◽  
Adaptive Responses ◽  
Short Term ◽  
Treatment Dose ◽  
Gastrointestinal Side Effects ◽  
Matched Design ◽  
Over Time

Production of reactive oxygen species (ROS) during muscle contractions is associated with muscle fatigue and damage in the short term and adaptive responses in the long term. When adaptation is inconsequential acute antioxidant supplementation may be able to attenuate muscle fatigue and damage to enhance performance. This study aimed to determine the effects of acute oral N-acetylcysteine (NAC) supplementation on Yo-Yo Intermittent Recovery Test Level 1 (YIRT-L1) performance after repeated bouts of damaging intermittent exercise. In a pair-matched design, 12 recreationally trained men engaged in 6 d of either NAC (n = 6) or placebo (n = 6) supplementation. After a treatment-loading day, participants completed 3 testing sessions, on alternating days, consisting of a preexercise isokinetic dynamometry (IKD) test, a damaging intermittent-exercise protocol, YIRT-L1, and a postexercise IKD test. Another IKD test was completed on the 2 intervening d. NAC treatment resulted in a significant preservation of YIRT-L1 performance (p ≤ .0005). IKD performance significantly deteriorated over time at all contraction speeds, and this deterioration was not influenced by treatment group. Plasma creatine kinase values increased significantly over time (p = .002) and were significantly greater in the NAC group than in the placebo group (p = .029). NAC induced mild gastrointestinal side effects. NAC supplementation may be a useful strategy to enhance performance during short-term competitive situations when adaption is inconsequential. Titration studies to elucidate a treatment dose that enhances performance without inducing side effects are now required.

scholarly journals Preventing co-infection: a viral strategy with short-term benefits and long-term drawbacks

2021 ◽  
Author(s):  
Michael Hunter ◽  
Diana Fusco
Keyword(s):  
Growth Rate ◽  
Life History ◽  
Negative Impact ◽  
Viral Evolution ◽  
Viral Fitness ◽  
Viral Population ◽  
Short Term ◽  
Life History Parameters ◽  
Wide Range

ABSTRACTViral co-infection occurs when multiple distinct viral particles infect the same host. This can impact viral evolution through intracellular interactions, complementation, reassortment and recombination. In nature many viral species are found to have a wide range of mechanisms to prevent co-infection, which raises the question of how viral evolution is impacted by this strategic choice. Here, we address this question in a model viral system, the ubiquitous bacteriophage and its host bacteria. Using a stochastic model of phage-host interactions in agent-based simulations, we first characterise the behaviour of neutral mutants and find that co-infection decreases the strength of genetic drift. We then quantify how variations in the phage life history parameters affect viral fitness. Importantly, we find that the growth rate (dis)advantage associated with variations in life history parameters can be dramatically different from the competitive (dis)advantage measured in direct-competition simulations. Additionally, we find that co-infection facilitates the fixation of beneficial mutations and the removal of deleterious ones, suggesting that selection is more efficient in co-infecting populations. We also observe, however, that in populations which allow co-infection, a mutant that prevents it displays a substantial competitive advantage over the rest of the population, and will eventually fix even if it displays a much lower growth rate in isolation. Our findings suggest that while preventing co-infection can have a negative impact on the long-term evolution of a viral population, in the short-term it is ultimately a winning strategy, possibly explaining the prevalence of phage capable of preventing co-infection in nature.

scholarly journals Nutrition in pregnancy: Basic principles and recommendations

2014 ◽  
Vol 142 (1-2) ◽  
pp. 125-130 ◽  
Author(s):  
Draga Plecas ◽  
Snezana Plesinac ◽  
Olivera Kontic-Vucinic
Keyword(s):  
Adult Life ◽  
Adverse Outcomes ◽  
Adaptive Responses ◽  
Normal Ranges ◽  
Energy Needs ◽  
Wide Range ◽  
Short And Long Term ◽  
Adverse Pregnancy ◽  
In Pregnancy

Healthy diet in pregnancy should guarantee proper fetal growth and development, maintain (and promote) maternal health and enable lactation. Nutritional counseling and interventions need to be an integral part of antenatal care and continue during pregnancy in order to reduce the risk of maternal, fetal and neonatal complications, as well as the short- and long-term adverse outcomes. Adverse pregnancy outcomes are more common in women who begin the gestation as undernourished or obese in comparison to pregnant women whose weight is within normal ranges. Increased nutritional and energy needs in pregnancy are met through numerous metabolic adaptations; pregnancy is successfully achieved within wide range of variations in energy supply and weight gain. However, if nutrient restriction exceeds the limits of adaptive responses, evidence indicates that fetus will develop the alternative metabolic competence that might emerge as a disease (type 2 diabetes, hypertension, coronary heart disease and stroke) in adult life.

scholarly journals How adaptive plasticity evolves when selected against

2018 ◽  
Author(s):  
Alfredo Rago ◽  
Kostas Kouvaris ◽  
Tobias Uller ◽  
Richard Watson
Keyword(s):  
Natural Selection ◽  
Environmental Change ◽  
Coarse Grained ◽  
Adaptive Plasticity ◽  
Short Term ◽  
Local Optima ◽  
Term Selection ◽  
Selection For ◽  
The Individual

AbstractAdaptive plasticity allows organisms to cope with environmental change, thereby increasing the population’s long-term fitness. However, individual selection can only compare the fitness of individuals within each generation: if the environment changes more slowly than the generation time (i.e., a coarse-grained environment) a population will not experience selection for plasticity even if it is adaptive in the long-term. How does adaptive plasticity then evolve? One explanation is that, if competing alleles conferring different degrees of plasticity persist across multiple environments, natural selection between lineages carrying those alleles could select for adaptive plasticity (lineage selection).We show that adaptive plasticity can evolve even in the absence of such lineage selection. Instead, we propose that adaptive plasticity in coarse-grained environments evolves as a by-product of inefficient short-term natural selection. In our simulations, populations that can efficiently respond to selective pressures follow short-term, local, optima and have lower long-term fitness. Conversely, populations that accumulate limited genetic change within each environment evolve long-term adaptive plasticity even when plasticity incurs short-term costs. These results remain qualitatively similar regardless of whether we decrease the efficiency of natural selection by increasing the rate of environmental change or decreasing mutation rate, demonstrating that both factors act via the same mechanism. We demonstrate how this mechanism can be understood through the concept of learning rate.Our work shows how plastic responses that are costly in the short term, yet adaptive in the long term, can evolve as a by-product of inefficient short-term selection, without selection for plasticity at either the individual or lineage level.

scholarly journals Slopes: solute processes and landforms

2021 ◽  
pp. M58-2021-5
Author(s):  
Tim Burt ◽  
Gilles Pinay ◽  
Fred Worrall ◽  
Nicholas Howden
Keyword(s):  
Drainage Basin ◽  
Nutrient Loss ◽  
Short Term ◽  
Carbon Export ◽  
Landform Evolution ◽  
Wide Range ◽  
Before And After ◽  
Forested Landscapes ◽  
Applied Fields

AbstractThis chapter reviews research on solutes by fluvial geomorphologists in the period 1965 to 2000; growing links with biogeochemical research are emphasised later in the chapter. Brief reference is necessarily made to some research from before and after the study period. In relation to solutes, early research sought to relate short-term process observations to long-term landform evolution. However, very quickly, research moved into much more applied fields, less concerned with landforms and more with biogeochemical processes. The drainage basin became the focus of research with a wide range of interest including nutrient loss from agricultural and forested landscapes to dissolved organic carbon export from peatlands. In particular, the terrestrial-aquatic ecotone became a focus for research, emphasising the distinctive processes operating in the riparian zone and their contribution to river water protection from land-derived pollutants. By the end of the period, the scale and range of fluvial geomorphology had been greatly transformed from what it had been in 1965, providing a distinctive contribution to the broader field of biogeochemistry as well as an ongoing contribution to the study of Earth surface processes and landforms.

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