scholarly journals Effect of host switching simulation on the fitness of the gregarious parasitoid Anaphes flavipes from a novel two-generation approach

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alena Samková ◽  
Jan Raška ◽  
Jiří Hadrava ◽  
Jiří Skuhrovec
Keyword(s):  
Host Plants ◽  
Host Switching ◽  
New Host ◽  
Individual Offspring ◽  
Gregarious Parasitoid ◽  
And Performance ◽  
F2 Generation ◽  
The Cost ◽  
The Impact ◽  
F1 Generation

AbstractHerbivorous insects can escape the strong pressure of parasitoids by switching to feeding on new host plants. Parasitoids can adapt to this change but at the cost of changing their preferences and performance. For gregarious parasitoids, fitness changes are not always observable in the F1 generation but only in the F2 generation. Here, with the model species and gregarious parasitoid Anaphes flavipes, we examined fitness changes in the F1 generation under pressure from the simulation of host switching, and by a new two-generation approach, we determined the impact of these changes on fitness in the F2 generation. We showed that the parasitoid preference for host plants depends on hatched or oviposited learning in relation to the possibility of parasitoid decisions between different host plants. Interestingly, we showed that after simulation of parasitoids following host switching, in the new environment of a fictitious host plant, parasitoids reduced the fictitious host. At the same time, parasitoids also reduced fertility because in fictitious hosts, they are not able to complete larval development. However, from a two-generation approach, the distribution of parasitoid offspring into both native and fictitious hosts caused lower parasitoid clutch size in native hosts and higher individual offspring fertility in the F2 generation.

Return on Invesment (ROI) of Software Product: A Systematic Literature Review

2015 ◽  
Vol 6 (1) ◽  
pp. 50-57
Author(s):  
Rizqa Raaiqa Bintana ◽  
Putri Aisyiyah Rakhma Devi ◽  
Umi Laili Yuhana
Keyword(s):  
Return On Investment ◽  
Assessment Criteria ◽  
Software Product ◽  
And Performance ◽  
Rational Consideration ◽  
Actual Return ◽  
The Cost ◽  
Investment Models ◽  
The Impact

The quality of the software can be measured by its return on investment. Factors which may affect the return on investment (ROI) is the tangible factors (such as the cost) dan intangible factors (such as the impact of software to the users or stakeholder). The factor of the software itself are assessed through reviewing, testing, process audit, and performance of software. This paper discusses the consideration of return on investment (ROI) assessment criteria derived from the software and its users. These criteria indicate that the approach may support a rational consideration of all relevant criteria when evaluating software, and shows examples of actual return on investment models. Conducted an analysis of the assessment criteria that affect the return on investment if these criteria have a disproportionate effort that resulted in a return on investment of a software decreased. Index Terms - Assessment criteria, Quality assurance, Return on Investment, Software product

Regulatory non-compliance and performance of deposit money banks in Nigeria

2018 ◽  
Vol 26 (3) ◽  
pp. 425-441 ◽  
Author(s):  
Ismaila Yusuf ◽  
Damola Ekundayo
Keyword(s):  
Emerging Economy ◽  
Bottom Line ◽  
Content Type ◽  
Correlational Research ◽  
And Performance ◽  
Using Data ◽  
The Cost ◽  
The Impact ◽  
Nigerian Banking ◽  
Practical Implications

Purpose The purpose of this study is to examine regulatory sanctions from an emerging economy perspective and analyzing the impact of regulators imposed monetary sanctions on banks’ performance. Design/methodology/approach The study adopted correlational research design to examine the effect of regulatory penalties on the performance of deposit money banks in Nigeria. This study used panel data from a sample of 15 deposit money banks in Nigeria for the period of 2006-2015. Multiple regression analysis was carried out. Findings Results showed that penalties imposed by regulators in the Nigerian banking industry have no significant impact on the bottom line of the defaulters. Penalties imposed on foreign exchange and international trade related infraction showed that the cost of penalties is below the benefits enjoyed from such infractions. Practical implications The insignificant impact of penalties on performance implies that deposit money banks have considered penalties imposed by regulators as operational expenses and transferred such to customers. Originality/value The study differs from other studies that examined regulatory penalties on performance by focusing on financial performance and using data from an emerging economy perceived to have weak regulatory environment.

scholarly journals The impact of life stage and pigment source on the evolution of novel warning signal traits

2020 ◽  
Author(s):  
Carita Lindstedt ◽  
Robin Bagley ◽  
Sara Calhim ◽  
Mackenzie Jones ◽  
Catherine Linnen
Keyword(s):  
Host Plants ◽  
Life Stage ◽  
Purifying Selection ◽  
Warning Signal ◽  
Carotenoid Content ◽  
Sawfly Larvae ◽  
Pine Sawfly ◽  
Novel Alleles ◽  
The Cost ◽  
The Impact

ABSTRACTOur understanding of how novel color traits evolve in aposematic taxa is based largely on studies of reproductive stages and organisms with endogenously produced pigmentation. In these systems, genetic drift is often required for novel alleles to overcome strong purifying selection stemming from frequency-dependent predation and positive assortative mating. Here we show that the importance of these mechanisms can differ if selective processes are considered in larval stage instead. By integrating population genomic data, predation experiments and phenotypic measurements of larvae and their host plants, we show that novel white alleles in Neodiprion lecontei (pine sawfly) larvae spread via selection rather than drift. The cost of being rare was not offset by an enhanced aposematic display or immune function. Instead, bottom-up selection via host plants may drive divergence among populations as white larvae were disproportionately abundant on a pine species with a reduced carotenoid content relative to other pine hosts.

scholarly journals Scarcity of hosts for gregarious parasitoids indicates an increase of individual offspring fertility by reducing their own fertility

2021 ◽  
Author(s):  
Alena Samková ◽  
Jan Raška ◽  
Jiří Hadrava ◽  
Jiří Skuhrovec
Keyword(s):  
Body Size ◽  
Reproductive Potential ◽  
Female Offspring ◽  
The Body ◽  
Individual Offspring ◽  
Single Host ◽  
Gregarious Parasitoid ◽  
Lower Mobility ◽  
Lower Fertility ◽  
F2 Generation

ABSTRACTThe gregarious parasitoid strategy allows multiple larvae to complete development in a single host due to their tolerance and/or lower mobility and thus flexibly adjust their reproductive potential amidst changing environmental conditions. Reproductive success is generally measured as the number of each mother’s offspring. We propose that with scarcity of host, for gregarious parasitoids is important the view on the fertility not only of a mother but also of her offspring (F1 generation). Due to the body size-fitness correlation, each female deliberately adjusts the clutch size, determining the offspring body size and their reproductive potential. In our study, using Anaphes flavipes as a model species, we showed that under a limited number of hosts, the females reduced their fertility. We propose that the lower fertility of mothers can cause higher fertility in the F2 generation using a larger offspring body while halving fertility. The females increase their individual offspring’s fertility by reducing their own fertility. Moreover, we showed that with a scarcity of hosts, the mothers increased the number of their female offspring, and thus, they obtained more offspring in the F2 generation. Additionally, other costs and benefits of the gregarious strategy in relation to superparasitism were tested and discussed.

scholarly journals Hygrothermal simulation and risk evaluation - The impact of discretization on numerical results and performance

2021 ◽  
Vol 2069 (1) ◽  
pp. 012033
Author(s):  
Andreas Sarkany ◽  
Thomas Bednar
Keyword(s):  
Risk Analysis ◽  
Risk Evaluation ◽  
Numerical Results ◽  
Computational Performance ◽  
Hygrothermal Simulation ◽  
Organic Vapour ◽  
And Performance ◽  
Thermal Simulations ◽  
The Cost ◽  
The Impact

Abstract Regulations for modelling when deducting thermal simulations are represented in the standards [1]. However, the level of model detail regarding discretization in hygrothermal simulations and especially for evaluating the mould risk on surfaces of organic vapour barriers is almost never discussed. The presented approach shows that the chosen discretization of the simulation model is one of the most influencing factors for the risk analysis of surfaces of very fine layers, such as paper vapour barriers, in walls with interior insulation via hygrothermal simulations. To reduce the computational performance issues caused by very fine finite volume meshes [2], the hygrothermal properties of the connecting surfaces of the finite volumes can be calculated instead. For the risk analysis the VTT-Model was implemented in the hygrothermal simulation program HAM4D_VIE, followed by a comparison of the effect of discretization on the results of the surfaces of the vapour barrier. The results of the comparison are discussed with regard to numerical results and their qualitative impact on computational performance. The presented numerical model will be proposed as an alternative for risk analysis on surfaces of vapour barriers, where mould growth would either stay undetected or the necessary discretization with elements comes at the cost of computational performance.

scholarly journals Evaluating the impact of excavator bucket capacity on the output of a haul truck in different variants of their positioning

2021 ◽  
Vol 2052 (1) ◽  
pp. 012001
Author(s):  
V V Aksenov ◽  
D M Dubinkin ◽  
A A Khoreshok ◽  
S O Markov ◽  
A B Efremenkov ◽  
...  
Keyword(s):  
Mutual Arrangement ◽  
Excavator Bucket ◽  
Technical And Economic Analysis ◽  
Truck Loading ◽  
Hydraulic Excavators ◽  
Significant Divergence ◽  
And Performance ◽  
The Cost ◽  
The Impact ◽  
Haul Truck

Abstract When studying the influence of excavator bucket capacity on haul truck loading time, it is necessary to assess the technical and economic performance of the complex. If the cost of the machine shift of the complex will not cover the increase in productivity, then it is inexpedient to use this complex. This issue requires further, more detailed study and performance of detailed technical and economic analysis. Also, it is necessary to consider classical recommendations about ratio of excavator bucket capacity and haul truck body. It should be noted that at present, there is a significant divergence in the size range of excavators: powerful, with a large capacity bucket, rope shovels are used for mining the coalless zone; small maneuverable hydraulic shovels – for mining the coal-bearing zone. In this paper, we will try to combine the first and the second: consider hydraulic excavators with maximum bucket capacity, which is reasonable to use when mining overburden. In addition, a detailed study of the options of mutual arrangement of excavator and haul truck has not been performed until recently, this work is intended to fill this gap.

scholarly journals The Impact of Wastewater Treatment Plants Transmitted Diseases on ITS Workforce

2019 ◽  
Vol 8 (12) ◽  
pp. 2852-2856
Keyword(s):  
Wastewater Treatment ◽  
Cohort Study ◽  
Wastewater Treatment Plants ◽  
New Employees ◽  
Water Company ◽  
Cost Efficient ◽  
And Performance ◽  
The Cost ◽  
The Impact ◽  
National Water

This work represents the research, analysis, and recommendation of a study that examined how wastewater treatment plants in the National Water Company in Jeddah workers get exposed to diseases in those environments which later affects their health and performance. The work carried out enables the company to evaluate how the most important risk is that of the employees contracting hepatitis A. In this case, the research was carried on 300 workers on National Water Company in Jeddah who works in these plants. The research study method or design used was an epidemiology perspective cohort study. All these workers had a similar characteristic which was the work environment but differed in various factors such as age, gender, and family history. The aim of the prospective cohort study was to see how workers safety is an issue, how the disease affects the performance of the workers and the cost side as well as how the Human Recourse department finds it hard in finding new employees. In this regard, it is important to note that preventing the disease is considerably more cost-efficient for the company that has to pay for the medical treatment of the sick employees and hire new employees that will perform the work of those sick while they recover. The report ends with both engineering and health recommendations that should be put in place to curb all the issues that wastewater brings to the workers.

Demonstrating Nutrient Cost Gradients: A Brooklyn Case Study

2014 ◽  
Vol 84 (5-6) ◽  
pp. 244-251 ◽  
Author(s):  
Robert J. Karp ◽  
Gary Wong ◽  
Marguerite Orsi
Keyword(s):  
Low Income ◽  
Energy Content ◽  
Food Selection ◽  
The United States ◽  
United States Department ◽  
Micronutrient Deficiencies ◽  
Caloric Density ◽  
Low Income Families ◽  
The Cost ◽  
The Impact

Abstract. Introduction: Foods dense in micronutrients are generally more expensive than those with higher energy content. These cost-differentials may put low-income families at risk of diminished micronutrient intake. Objectives: We sought to determine differences in the cost for iron, folate, and choline in foods available for purchase in a low-income community when assessed for energy content and serving size. Methods: Sixty-nine foods listed in the menu plans provided by the United States Department of Agriculture (USDA) for low-income families were considered, in 10 domains. The cost and micronutrient content for-energy and per-serving of these foods were determined for the three micronutrients. Exact Kruskal-Wallis tests were used for comparisons of energy costs; Spearman rho tests for comparisons of micronutrient content. Ninety families were interviewed in a pediatric clinic to assess the impact of food cost on food selection. Results: Significant differences between domains were shown for energy density with both cost-for-energy (p < 0.001) and cost-per-serving (p < 0.05) comparisons. All three micronutrient contents were significantly correlated with cost-for-energy (p < 0.01). Both iron and choline contents were significantly correlated with cost-per-serving (p < 0.05). Of the 90 families, 38 (42 %) worried about food costs; 40 (44 %) had chosen foods of high caloric density in response to that fear, and 29 of 40 families experiencing both worry and making such food selection. Conclusion: Adjustments to USDA meal plans using cost-for-energy analysis showed differentials for both energy and micronutrients. These differentials were reduced using cost-per-serving analysis, but were not eliminated. A substantial proportion of low-income families are vulnerable to micronutrient deficiencies.

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