2,081 research outputs found

    Evolutionary Dynamics of Fearfulness and Boldness: A Stochastic Simulation Model

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    A stochastic simulation model is investigated for the evolution of anti-predator behavior in birds. The main goal is to reveal the effects of population size, predation threats, and energy lost per escape on the evolutionary dynamics of fearfulness and boldness. Two pure strategies, fearfulness and boldness, are assumed to have different responses for the predator attacks and nonlethal disturbance. On the other hand, the co-existence mechanism of fearfulness and boldness is also considered. For the effects of total population size, predation threats, and energy lost per escape, our main results show that: (i) the fearful (bold) individuals will be favored in a small (large) population, i.e. in a small (large) population, the fearfulness (boldness) can be considered to be an ESS; (ii) in a population with moderate size, fearfulness would be favored under moderate predator attacks; and (iii) although the total population size is the most important factor for the evolutionary dynamics of both fearful and bold individuals, the small energy lost per escape enables the fearful individuals to have the ability to win the advantage even in a relatively large population. Finally, we show also that the co-existence of fearful and bold individuals is possible when the competitive interactions between individuals are introduced

    Variations of Physiological Parameters and HSP70 and HSP90 Polymorphisms in Water Buffaloes in Taiwan During Cool and Warm Season

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    Background: This study examined the physiological parameters of water buffaloes in Taiwan in the cool (February) and warm (August) seasons of 2020 and 2021. Methods: Data was collected for a study in February, August 2020, and 2021. The ambitious temperature, humidity, water buffaloes’ rectal temperature (RT), and respiratory rate (RR) were recorded. The plasma expression levels of heat-shock protein (HSP)70 and HSP90 were examined using an ELISA kit. Furthermore, the HSP70 and HSP90 fragment genetic sequence variations were analyzed using the PCR method and MEGA6 software. Results: The results revealed that in the warm season, the rectal temperature (RT), respiratory rate (RR), and heat tolerance coefficient (HTC) were significantly higher compared to the cool season (all P < 0.05). Additionally, the temperature-humidity index (THI) had moderate to high correlations with RT (0.518), RR (0.744), and HTC (0.757). Plasma HSP70 expression levels were higher in the warm season than in the cool season (P < 0.05). The genetic sequences of HSP70 and HSP90 fragments were compared, and five single-nucleotide variation (SNV) sites were identified. However, each genotype showed no significant physiological difference between the cool and warm seasons. Conclusion: Temperature and humidity changes in Taiwan had a significant correlation with the physical condition of water buffaloes. This information can be valuable in improving the living conditions of these animals, leading to better animal welfare. Additionally, the HSP70 and HSP90 gene variations in water buffaloes in Taiwan could be used as a reference for future research on breeding and identifying molecular markers

    A Summary Review of Correlations between Temperatures and Vibration Properties of Long-Span Bridges

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    The shift of modal parameters induced by temperature fluctuation may mask the changes of vibration properties caused by structural damage and result in false structural condition identification. Thoroughly understanding the temperature effects on vibration properties of long-span bridges becomes an especially important issue before vibration-based damage detection methodologies are applied in real bridges. This paper presents an overview of current research activities and developments in the field of correlations between temperatures and vibration properties of long-span bridges. The theoretical derivation methods using classical structural dynamics and closed-form formulations are first briefly introduced. Then the trend analysis methods that are intended to extract the degree of variability in vibration property under temperature variation for different bridges by numerical analysis, laboratory test, or field monitoring are reviewed in detail. Following that, the development of quantitative models to quantify the temperature influence on vibration properties is discussed including the linear model, nonlinear model, and learning model. Finally, some promising research efforts for promoting the study of correlations between temperatures and vibration properties of long-span bridges are suggested

    Safety Early Warning Research for Highway Construction Based on Case-Based Reasoning and Variable Fuzzy Sets

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    As a high-risk subindustry involved in construction projects, highway construction safety has experienced major developments in the past 20 years, mainly due to the lack of safe early warnings in Chinese construction projects. By combining the current state of early warning technology with the requirements of the State Administration of Work Safety and using case-based reasoning (CBR), this paper expounds on the concept and flow of highway construction safety early warnings based on CBR. The present study provides solutions to three key issues, index selection, accident cause association analysis, and warning degree forecasting implementation, through the use of association rule mining, support vector machine classifiers, and variable fuzzy qualitative and quantitative change criterion modes, which fully cover the needs of safe early warning systems. Using a detailed description of the principles and advantages of each method and by proving the methods’ effectiveness and ability to act together in safe early warning applications, effective means and intelligent technology for a safe highway construction early warning system are established

    Effects of insecticide-treated net access and use on infant mortality in Malawi: A pooled analysis of demographic health surveys

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    Malaria continues to be among the top causes of death in children and insecticide-treated nets (ITNs) are considered among the most effective malaria control methods. However, information on the association between universal ITN coverage and infant mortality is limited. A Cox proportional hazard model was applied to Malawi Demographic and Health Surveys to determine the association between ITN access and use and infant mortality between 2004 and 2015–2016. The overall infant mortality rate for the entire period was 47.9/1000 live births. Infants from the ITN-user households exhibited a lower risk of mortality [adjusted Hazard Ratio (aHR) = 0.61, 95% Confidence Interval (CI) = 0.44–0.85] than those from the ITN-nonuser households. Similarly, the infants from the high-access households exhibited a lower risk of death (aHR = 0.63, 95% CI = 0.46–0.86) than those from the no-access households. Infants from the ITN-user and high-access households exhibited a significantly lower risk of death (aHR = 0.57, 95% CI = 0.40–0.82) than those from the ITN-nonuser and no-access households. The relationship between ITN access and use and infant mortality was significant among female infants with a second or higher birth order and interval of ≥2 years. The findings of the present population-based study emphasized the importance of ITN access and use in providing optimal protection against malaria to infants in Malawi. Malaria control programs should ensure high ITN access and use in Malawi to reduce infant mortality

    Multilevel analysis of factors associated with treatment-seeking behaviors among caregivers with febrile children in Malawi

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    Early diagnosis and treatment of childhood fever, an important sign of potentially serious infections such as malaria, is essential for controlling disease progression, and ultimately, preventing deaths. This study examined individual- and community-level factors associated with treatment-seeking behaviors and promptness in these behaviors among caregivers of febrile under-five children in Malawi. The 2015-2016 Malawi Demographic Health Survey was used to analyze a nationally representative sample of 4,133 under-five children who had fever within 2 weeks before the survey. A multilevel logistic regression model was used to examine the association between individual- and community-level factors and treatment-seeking behaviors. Approximately 67.3% of the caregivers reported seeking treatment for their febrile child, whereas only 46.3% reported promptly seeking treatment. Children from communities with moderate and high percentages of educated caregivers were more likely to be taken for treatment (adjusted odds ratio [aOR] = 1.26, 95% CI = 1.01-1.58 and aOR = 1.31, 95% CI = 1.02-1.70, respectively) than those from communities with a low percentage of educated caregivers. Children from communities with moderate and high percentages of caregivers complaining about the distance to a health facility were less likely to be taken for treatment (aOR = 0.74, 95% CI = 0.58-0.96 and aOR = 0.67, 95% CI = 0.51-0.88, respectively). At the individual level, having a cough in the last 2 weeks, region, religion, and having better health behaviors in other health dimensions were associated with fever treatment-seeking behaviors among Malawian caregivers. Programs aimed at improving treatment-seeking behaviors should consider these factors and the regional variations observed in this study

    Investment Decision Support for Engineering Projects Based on Risk Correlation Analysis

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    Investment decisions are usually made on the basis of the subjective judgments of experts subjected to the information gap during the preliminary stages of a project. As a consequence, a series of errors in risk prediction and/or decision-making will be generated leading to out of control investment and project failure. In this paper, the variable fuzzy set theory and intelligent algorithms integrated with case-based reasoning are presented. The proposed algorithm manages the numerous fuzzy concepts and variable factors of a project and also sets up the decision-making process in accordance with past cases and experiences. Furthermore, it decreases the calculation difficulty and reduces the decision-making reaction time. Three types of risk correlations combined with different characteristics of engineering projects are summarized, and each of these correlations is expounded at the project investment decision-making stage. Quantitative and qualitative change theories of variable fuzzy sets are also addressed for investment risk warning. The approach presented in this paper enables the risk analysis in a simple and intuitive manner and realizes the integration of objective and subjective risk assessments within the decision-makers' risk expectation
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