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Abstract Background Resilience is the capacity of an animal to be minimally affected by disturbances or to rapidly return to its initial state before exposure to a disturbance. Resilient livestock are desired because of their improved health and increased economic profit. Genetic improvement of resilience may also lead to trade-offs with production traits. Recently, resilience indicators based on longitudinal data have been suggested, but they need further evaluation to determine whether they are indeed predictive of improved resilience, such as disease resilience. This study investigated different resilience indicators based on deviations between expected and observed egg production (EP) by exploring their genetic parameters, their possible trade-offs with production traits, and their relationships with antibody traits in chickens. Methods Egg production in a nucleus breeding herd environment based on 1-week-, 2-week-, or 3-week-intervals of two purebred chicken lines, a white egg-laying (33,825 chickens) and a brown egg-laying line (34,397 chickens), were used to determine deviations between observed EP and expected average batch EP, and between observed EP and expected individual EP. These deviations were used to calculate three types of resilience indicators for two life periods of each individual: natural logarithm-transformed variance (ln(variance)), skewness, and lag-one autocorrelation (autocorrelation) of deviations from 25 to 83 weeks of age and from 83 weeks of age to end of life. Then, we estimated their genetic correlations with EP traits and with two antibody traits. Results The most promising resilience indicators were those based on 1-week-intervals, as they had the highest heritability estimates (0.02–0.12) and high genetic correlations (above 0.60) with the same resilience indicators based on longer intervals. The three types of resilience indicators differed genetically from each other, which indicates that they possibly capture different aspects of resilience. Genetic correlations of the resilience indicator traits based on 1-week-intervals with EP traits were favorable or zero, which means that trade-off effects were marginal. The resilience indicator traits based on 1-week-intervals also showed no genetic correlations with the antibody traits, which suggests that they are not informative for improved immunity or vice versa in the nucleus environment. Conclusions This paper gives direction towards the evaluation and implementation of resilience indicators, i.e. to further investigate resilience indicator traits based on 1-week-intervals, in breeding programs for selecting genetically more resilient layer chickens.

Abstract Background There is growing interest in using genetic selection to obtain more resilient farm animals (i.e. that are minimally affected by disturbances or rapidly recover from them). The aims of this study were to: (i) estimate the genetic parameters of resilience indicator traits based on egg production data, (ii) assess whether these traits are genetically correlated in purebreds and crossbreds, and (iii) assess the genetic correlations of these traits with egg production (EP) as total number of eggs between 25 and 83 weeks. Purebred hens (33,825 from a White Leghorn (WA) line and 34,397 from a Rhode Island (BD) line were housed in individual cages, while crossbred hens were housed in collective cages of 6 to 8 paternal half-sibs (12,852 WA and 3898 BD crossbred groups, where the name of the group refers to the line used as the sire). Deviations of a hen’s weekly egg production from the average of the corresponding batch were calculated. Resilience indicator traits investigated were the natural logarithm of the variance (LNVAR), the skewness (SKEW), and the lag-one autocorrelation (AUTO-R) of these deviations. Results In both purebred lines, EP was estimated to be lowly heritable (WA: 0.11 and BD: 0.12). Resilience indicators were also estimated to be lowly heritable in both lines (LNVAR: 0.10 and 0.12, SKEW: 0.04 and 0.02, AUTO-R: 0.06 and 0.08 in WA and BD, respectively). In both crossbred groups, EP, AUTO-R, and SKEW were estimated to be less heritable than in purebreds (EP: $$h^{2}$$ h 2 ≤ 0.07; and resilience indicator traits: $$h^{2}$$ h 2 ≤ 0.03), while LNVAR had an $$h^{2}$$ h 2 estimate that was similar to or higher in crossbreds ( $$h^{2}$$ h 2 ranged from 0.13 to 0.21) than in purebreds. In both purebreds and crossbreds, resilience indicator traits were estimated to have favorable genetic correlations with EP and between each other. For all traits and in both lines, estimates of genetic correlations between purebreds and crossbreds ( $$r_{pc}$$ r pc ) differed from 1 and ranged from 0.16 to 0.63. Conclusions These results show that selection for resilience based on EP data can be considered in breeding programs for layers. Genetic improvement of resilience in crossbreds can be achieved by using information on purebreds, but would be greatly enhanced by the integration of information on crossbreds in breeding programs.

Abstract Background Resilient animals are minimally affected by disturbances, such as diseases and heat stress, and quickly recover. Daily activity data can potentially indicate resilience, because resilient animals likely keep variations due to disturbances that threat animal homeostasis at a low magnitude. We used daily step count of cows to define resilience indicators based on theory, exploratory analysis and literature, and then investigated if they can be used to genetically improve resilience by estimating heritability and repeatability, and genetic associations with other resilience-related traits, i.e. health traits, longevity, fertility, and body condition score (BCS). Results Two groups of resilience indicators were defined: indicators describing (1) mean step count at different lactation stages for individual cows, and (2) fluctuations in step count from individual step count curves. Heritability estimates were highest for resilience indicators describing mean step count, from 0.22 for the 2-week period pre-partum to 0.45 for the whole lactation. High mean step count was consistently, but weakly, genetically correlated with good health, fertility, and longevity, and high BCS. Heritability estimates of resilience indicators describing fluctuations ranged from 0.01 for number of step count drops to 0.15 for the mean of negative residuals from individual curves. Genetic correlations with health traits, longevity, fertility, and BCS were mostly weak, but were moderate and favorable for autocorrelation of residuals (− 0.33 to − 0.44) and number of step count drops (− 0.44 to − 0.56) with hoof health, fertility, and BCS. Resilience indicators describing variability of residuals and mean of negative residuals showed strong genetic correlations with mean step count (0.86 to 0.95, absolute), which suggests that adjustment for step count level is needed. After adjustment, ‘mean of negative residuals’ was highly genetically correlated with hoof health, fertility, and BCS. Conclusions Mean step count, autocorrelation and mean of negative residuals showed most potential as resilience indicators based on resilience theory, heritability, and genetic associations with health, fertility, and body condition score. Other resilience indicators were heritable, but had unfavorable genetic correlations with several health traits. This study is an important first step in the exploration of the use of activity data to breed more resilient livestock.

Abstract Background High resistance (the ability of the host to reduce pathogen load) and tolerance (the ability to maintain high performance at a given pathogen load) are two desirable host traits for producing animals that are resilient to infections. For Porcine Reproductive and Respiratory Syndrome (PRRS), one of the most devastating swine diseases worldwide, studies have identified substantial genetic variation in resistance of pigs, but evidence for genetic variation in tolerance has so far been inconclusive. Resistance and tolerance are usually considered as static traits. In this study, we used longitudinal viremia measurements of PRRS virus infected pigs to define discrete stages of infection based on viremia profile characteristics. These were used to investigate host genetic effects on viral load (VL) and growth at different stages of infection, to quantify genetic variation in tolerance at these stages and throughout the entire 42-day observation period, and to assess whether the single nucleotide polymorphism (SNP) WUR10000125 (WUR) with known large effects on resistance confers significant differences in tolerance. Results Genetic correlations between resistance and growth changed considerably over time. Individuals that expressed high genetic resistance early in infection tended to grow slower during that time-period, but were more likely to experience lower VL and recovery in growth by the later stage. The WUR genotype was most strongly associated with VL at early- to mid-stages of infection, and with growth at mid- to late-stages of infection. Both, single-stage and repeated measurements random regression models identified significant genetic variation in tolerance. The WUR SNP was significantly associated only with the overall tolerance slope fitted through all stages of infection, with the genetically more resistant AB pigs for the WUR SNP being also more tolerant to PRRS. Conclusions The results suggest that genetic selection for improved tolerance of pigs to PRRS is possible in principle, but may be feasible only with genomic selection, requiring intense recording schemes that involve repeated measurements to reliably estimate genetic effects. In the absence of such records, consideration of the WUR genotype in current selection schemes appears to be a promising strategy to improve simultaneously resistance and tolerance of growing pigs to PRRS.

Abstract Background Genome editing technologies provide new tools for genetic improvement and have the potential to become the next game changer in animal and plant breeding. The aim of this study was to investigate how genome editing in combination with genomic selection can accelerate the introduction of a monogenic trait in a livestock population as compared to genomic selection alone. Methods A breeding population was simulated under genomic selection for a polygenic trait. After reaching Bulmer equilibrium, the selection objective was to increase the allele frequency of a monogenic trait, with or without genome editing, in addition to improving the polygenic trait. Scenarios were compared for time to fixation of the desired allele, selection response for the polygenic trait, and level of inbreeding. The costs, in terms of number of editing procedures, were compared to the benefits of having more animals with the desired phenotype of the monogenic trait. Effects of reduced editing efficiency were investigated. Results In a population of 20,000 selection candidates per generation, the total number of edited zygotes needed to reach fixation of the desired allele was 22,118, 7072, or 3912 with, no, moderate, or high selection emphasis on the monogenic trait, respectively. Genome editing resulted in up to four-fold faster fixation of the desired allele when efficiency was 100%, while the loss in long-term selection response for the polygenic trait was up to seven-fold less compared to genomic selection alone. With moderate selection emphasis on the monogenic trait, introduction of genome editing led to a four-fold reduction in the total number of animals showing the undesired phenotype before fixation. However, with a currently realistic editing efficiency of 4%, the number of required editing procedures increased by 72% and loss in selection response increased eight-fold compared to 100% efficiency. With low efficiency, loss in selection response was 29% more compared to genomic selection alone. Conclusions Genome editing strongly decreased the time to fixation for a desired allele compared to genomic selection alone. Reduced editing efficiency had a major impact on the number of editing procedures and on the loss in selection response. In addition to ethical and welfare considerations of genome editing, a careful assessment of its technical costs and benefits is required.

Abstract Background A host can adopt two response strategies to infection: resistance (reduce pathogen load) and tolerance (minimize impact of infection on performance). Both strategies may be under genetic control and could thus be targeted for genetic improvement. Although there is evidence that supports a genetic basis for resistance to porcine reproductive and respiratory syndrome (PRRS), it is not known whether pigs also differ genetically in tolerance. We determined to what extent pigs that have been shown to vary genetically in resistance to PRRS also exhibit genetic variation in tolerance. Multi-trait linear mixed models and random regression sire models were fitted to PRRS Host Genetics Consortium data from 1320 weaned pigs (offspring of 54 sires) that were experimentally infected with a virulent strain of PRRS virus to obtain genetic parameter estimates for resistance and tolerance. Resistance was defined as the inverse of within-host viral load (VL) from 0 to 21 (VL21) or 0 to 42 (VL42) days post-infection and tolerance as the slope of the reaction-norm of average daily gain (ADG21, ADG42) on VL21 or VL42. Results Multi-trait analysis of ADG associated with either low or high VL was not indicative of genetic variation in tolerance. Similarly, random regression models for ADG21 and ADG42 with a tolerance slope fitted for each sire did not result in a better fit to the data than a model without genetic variation in tolerance. However, the distribution of data around average VL suggested possible confounding between level and slope estimates of the regression lines. Augmenting the data with simulated growth rates of non-infected half-sibs (ADG0) helped resolve this statistical confounding and indicated that genetic variation in tolerance to PRRS may exist if genetic correlations between ADG0 and ADG21 or ADG42 are low to moderate. Conclusions Evidence for genetic variation in tolerance of pigs to PRRS was weak when based on data from infected piglets only. However, simulations indicated that genetic variance in tolerance may exist and could be detected if comparable data on uninfected relatives were available. In conclusion, of the two defense strategies, genetics of tolerance is more difficult to elucidate than genetics of resistance.

A cusp is a curve which is made by projecting a smooth curve in the 3D Euclidean space on a plane. Such a projection results in a curve whose singularities are self-crossing points or ordinary cusps. Self-crossing points created when two different points of the curves have the same projection at a point. Ordinary cusps created when the tangent to the curve is parallel to the direction of projection on a single point. The study of a cusp geometry beam is more complex than that of a straight beam because the structural deformations of the cusp geometry beam depend also on the coupled tangential displacement caused by the singular geometry. The Isogeometric Approach (IGA) is a computational geometry based on a series of polynomial basis functions used to represent the exact geometry. In IGA, the cusp geometry of the beam element can be modeled exactly. A thick cusp geometry beam element can be developed based on the Timoshenko beam theory, which allows the vertical shear deformation and rotatory inertia effects. The shape of the beam geometry and the shape functions formulation of the element can be obtained from IGA. However, in IGA, the number of equations will increase according to the number of degree of freedom (DOF) at the control points. A new condensation method is adopted to reduce the number of equations at the control points so that it becomes a standard two-node 6-DOF beam element. This paper highlights the application of IGA of a cusp geometry Timoshenko beam element in the context of finite element analysis and proposes a new condensation method to eliminate the drawbacks elevated by the conventional IGA. Examples are given to verify the effectiveness of the condensation method in static and free vibration problems.

The economic development in Guangzhou presents an export-oriented characteristic. Therefore, it is the key path for Guangzhou’s manufacturing to upgrade by participating the construction of the Belt and Road initiative. This paper adopts Lafay Index to measure the structural competitiveness of trade between China and countries along the B&R and finds that Guangzhou has a long-term and stable comparative advantage in clothing and textile industry, metal products industry and leather products industry, but a long-term disadvantage in metal smelting industry, chemical manufacturing industry and non-metallic mineral products. It also shows a high degree of intra-industry trade in food processing industry, sports and entertainment industry.

A gradation pattern in the strength of concrete columns is unavoidable due to the presence of static and dynamic segregation. The effect of concrete uniformity on columns subjected to monotonic lateral load is investigated experimentally in this study. Reinforced concrete columns with cross-sectional dimensions of 150 x 150 mm and a height of 1000 mm are prepared as graded concrete column (GCC) specimens and controlling specimens. The columns are designed with a reinforcement ratio of 1%. Two concrete mixes with a strength of 20 MPa and 30 MPa are cast in moulds using the gradual compaction procedure to create a satisfactory strength transition throughout the specimens’ height. The resulting lateral deformation and resisting load are utilised for further analysis. The analyses show that the GCC exhibits a lower peak load and lateral deformation than the control specimen, and a distinct failure mode is observed. The GCC also shows more brittle behaviour in the post-peak region.

Owing to continuously changing strength moduli properties, functionally graded concrete (FGC) has remarkable advantages over the traditional homogeneous concrete materials regarding cement optimization. Some researchers have studied mechanical behaviors and production methodologies. Problems arise as to how to incorporate the effects of the non-homogeneity of concrete strengths in the analysis for design. For a steel Reinforced Functionally Graded Concrete (RFGC) beam structure, the associated boundary conditions at both ends have to be at the neutral axis position after the occurrence of the presumed cracks. Because the neutral axis is no longer at the mid-plane of the beam crosssection, an iterative procedure has to be implemented. The procedure is somewhat complicated since the strength of the beam cross section has to be integrated due to the non-homogeneity in concrete strengths. This paper proposes an analytical procedure that is very straightforward and simple in concept, but accurate in designing the steel reinforced functionally graded concrete beam cross-sections.

Research on geopolymer concrete has seen a new light in the analyses and experiments for special topics in the field of their mechanical properties. Among the most important are studies of geopolymer concrete subjected to confinement and bond. Regarding the basic material behavior, research of material proportions formulations, mix design formulas and inventions towards the development of a high-performance geopolymer concrete, were conducted. The latest looked into the effects of molar activator concentrations to the 28 days compression strength, and the strength development as a function of concrete age for geopolymer concretes. The specimens were 150 by 300-millimeter cylinders tested in uniaxial compression. The molarity variations were set at 6, 8, and 10 molars. The geopolymer concrete samples were compared to conventional concrete specimens, having the exact same volumetric material proportions. The cement was replaced with fly ash, and the activator with water. The aggregate content was taken as a constant. The concrete strength as a function of molar increase followed a parabolic, convex pattern, suggesting that a maximum value exists. The strength development of all geopolymer concretes had a slower rate when compared to conventional concrete.

The use of external reinforcement has gained an increasingly major position due to the adjustment in earthquake standards, mandating a significant improvement in the section’s moment capacity. Studies on the behavior and enhancement contributed by FRP sheets demonstrated that its effectiveness was a direct function of the shear-bond strength. A prominent contributing factor was the response of the interface between the sheets and the epoxy resin, and the interface between the epoxy resin to the concrete surface. Recently, FRP rods were produced. These rods which are 8 and 10 millimeters in diameter offer ease in use, and simplicity in the application procedure. This study looked into the shear-bond behavior of FRP rods as compared to sheets. Direct tensile stresses were applied to test the shearbond between the sheets and rods, attached to a 35 MPa concrete surface. The failure behavior of the bond was also monitored. Additionally, the effectiveness of the embedded depth of the FRP rods relative to the concrete surface was also analyzed.

The elastic modulus of materials plays a role in determining the stiffness of a structural element and its level of serviceability. Previous research indicates that the concrete modulus of elasticity could be improved by combining 2 (two) concrete mixes using a gradual compacting method. In this study, the effect of different concrete strength combinations to the resulting modulus of elasticity is examined. Three types of concrete mixes with a strength of 30 MPa, 40 MPa and 50 MPa are prepared. The graded concrete is moulded in cylindrical concrete casts (150 mm x 300 mm) with the following casting configurations: 30-40 MPa, 30-50 MPa, and 40-50 MPa. The static modulus of elasticity test is performed at an age of 28 days using compressometers in accordance with ASTM C469. The test results show that the modulus of elasticity of the graded concrete is proportionally influenced by the stiffness of the higher and the lower concrete material. Additionally, the resulting compressive strength of the graded concrete is determined by the lower concrete strength.

The use of castellated beams has become more popular in the last two decades. The main idea for the use of these types of steel beams is to reduce their self-weight by providing openings in the web of wide flange (WF) or I sections. Numerous research on castellated beams has been conducted, the majority of the studies aimed to optimize the opening size and the shape configuration of the openings. A numerical analysis of castellated beams with oval openings was performed in this study. The sections under investigation had variations in the height-to-length ratios of the beam. The Do to D and b to Do ratios were kept at a constant. The D value was defined as the height of the beam, while Do is the height of the opening, and b is the width of the opening. The numerical analysis was performed by the finite element analysis using the STRAND7 software. The numerical model was further validated to the experimental data. The results showed that the developed finite element model resulted in a very good representation to the actual behavior of the sections.

AP1000 is a standard nuclear power plant developed by Westinghouse and its partners by using an advanced passive safety feature. Among the five principle building structures, namely the nuclear island, turbine building, annex building, diesel generator building and radwaste building, the safety of the nuclear island building is the most concerned. This paper investigates the dynamic response of the nuclear island building of the AP1000 plant subjected to safe shutdown earthquake loadings. A finite element model for the building, which is assumed to be built in a hard-rock base, is developed and its dynamic response is computed with the aid of the commercial finite element package ANSYS. The dynamic characteristics, including the natural frequencies, the vibration modes, and the time histories for displacements, velocities, and accelerations of the building are obtained for two typical safe shutdown earthquakes, El Centro and Kobe earthquakes. The dynamic behavior of the building due to the earthquakes and its safety is examined and highlighted.

Sn-Bi solders are considered by PV manufacturers as acceptable Pb-free alternative due to its low operating temperature and cost, despite being prone to brittleness caused by coarse Bi phases. Bamboo charcoal (BC) is a sustainable and environment-friendly resource with high surface area and its addition to Sn-Bi solder meets the requirement of a green solder, in line with environmental regulations. This study aims to improve the shear strength and reduce brittleness of the Sn-Bi solder alloy by using a sustainable reinforcement, the activated bamboo charcoal. Sn-58Bi solder paste was reinforced with 0.25, 0.50, 0.75 and 1.00 wt.% of activated BC, respectively and reflowed to create a single lap shear joint. Aging response was determined through accelerated aging at 120 °C for 7 days and 14 days. Shear strength of the joints increased as the activated BC content increased in the as-reflowed condition and there was lower degradation in shear strength for heat-aging specimens compared to pure Sn-Bi solder. No failures occurred via Mode 3 when the as-reflowed samples contained 0.50 wt.% or more of activated BC, and the 7- and 14-day heat-aged samples were free from Mode 3 failures when the activated BC composition was at 0.75 wt.% and above. Fracture surfaces showed transitions from flat and smooth surface to elongated-dimple structures even with just 0.25 wt.% of activated BC addition. While prolonged heat-aging increased cleavage presence, increasing amounts of activated BC reduced facet numbers and dimple sizes, indicating successful suppression of Bi phase segregation.

The article proposes an approach to the current situation of the Catholic Church and theology in South Korea. After noting a certain stagnation in the current situation of the Church, it considers that one of the greatest challenges of theology lies in the transmission of the faith to new generations, in circumstances many different from the previous ones. From a contextual point of view, the challenge is reinforced by the growing presence of new Christian confessions and sects in the territory, as well as by the effects of the pandemic. The near future will be marked by the impact of artificial intelligence and the synodal movement in the Church. [ABSTRACT FROM AUTHOR]