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The purpose of this study is to reveal the effect of coaching leadership on organizational trust and organizational citizenship behavior depending on the level of psychological safety. Specifically, the relationship between coaching leadership and organizational citizenship behavior was examined and the mediating effect of organizational trust was identified in the effect of coaching leadership on organizational citizenship behavior. In addition, this study examined a moderating effect of psychological safety on the relationship between organizational trust and organizational citizenship behavior Finally, the relationship between coaching leadership and organizational citizenship behavior is verified by the moderated mediating effect of psychological safety in the mediation of organizational trust. For this purpose, data from 300 Korean workers were collected through an online questionnaire survey, and analyzed the materials using SPSS 25.0 and Macro. As a result of the research, the relationship between coaching leadership and organizational citizenship behavior has been proven to have a partial mediating effect significantly by organizational trust. The moderating effect of the psychological safety and the moderated mediating effect were also both significant. Finally, we discussed implications, limitations, and future research.

Long-term stability of organic blends is a key factor for the practical use of organic solar cells (OSCs) in commercial fields. Here, we report the strategic incorporation of non-fullerene small molecules in polymer:fullerene blends to obtain ternary OSCs with improved efficiency and extended lifetimes. Non-fullerene small molecules employed in the polymer:fullerene blend successfully increased the photon-to-current conversion process as an efficient charge cascade acceptor. A combination of theoretical simulations and experimental measurements revealed that aggregation of meta-stable fullerene molecules was significantly alleviated in the ternary blend, thereby preventing an unintentional increase in the threshold for charge transfer during operation. Thus, the ternary OSCs could exhibit highly extended lifetimes with improved morphological stability and better resistance to performance decay under harsh real operational conditions compared to their binary counterparts. Combined with its high efficiency and improved device lifetimes, the high tolerance to the ternary blend thickness offers promise for commercially acceptable ternary OSCs fabricated by a printing process.

Salinity has been a threat to agriculture in some parts of the world; and recently, the threat has grown. Plant growth-promoting rhizobacteria (PGPR) may benefit plant growth, either by improving plant nutrition or producing plant growth hormones. The effects of rhizobacterial strains to attenuate the salinity stress on the germination of Chinese cabbage seeds were tested using four different concentrations of NaCl (50, 100, 150, and 200 mM). Also, PGPR strains were tested to enhance the early germination of Chinese cabbage seeds under normal conditions. Azotobacter chroococcum performed best with enhancing the radicle length of 4.0, 1.2, and 1.0 times at treatments of 50, 100, and 150 mM of NaCl, respectively. Additionally, significant differences were found in plumule length, A. chroococcum and Lactobacillus sp. showed remarkable activation either in normal or under stress conditions. Co-inoculation by three rhizobacterial strains (LAPmix) indicated synergistic effect to enhance the early germination of the seeds. The results of this study are promising for application of rhizobacterial strains that possess plant growth promoting traits to enhance the plant tolerance against salinity.

The effect of the alloying elements, the carbon, nickel, and the titanium in particular, on the hot ductility behavior of high manganese steel for cryogenic applications was investigated. A hot ductility test was carried out to clarify the mechanism of the heat affected zone (HAZ) liquation and ductility dip cracking that were observed at the HAZ of multi-pass welds. The brittle temperature range, critical strain temperature range, and overall ductility for each alloy were varied due to differences of the eutectic temperatures and the degree of dynamic recrystallization (DRX). The temperature of constitutional liquation between TiC and the austenitic matrix as well as the eutectic temperature of M 3 C/γ were determined based on the Ti/C ratio and Ti content in the Fe Ti C ternary system. The onset and degree of DRX depended on the grain size, the secondary particle distribution and the chemical composition that determines the stacking fault energy of each alloy. The HAZ cracking was consistent with aspects of liquation cracking including the constitutional liquation between the TiC and austenitic matrix, its reaction temperature, the final M 3 C/γ eutectic temperature, extent of liquation, followed by the ductility dip crack that was formed along with resolidified grain boundaries under the DRX temperature.

Prediction of growth patterns of commercial chicken strains is important. It can provide visual assessment of growth as function of time and prediction body weight (BW) at a specific age. The aim of current study is to compare the three nonlinear functions (i.e., Logistic, Gompertz, and von Betalanffy) for modeling the growth of twenty five commercial Korean native chicken (KNC) strains reared under a battery cage system until 32 weeks of age and to evaluate the three models with regard to their ability to describe the relationship between BW and age. A clear difference in growth pattern among 25 strains were observed and classified in to the groups according to their growth patterns. The highest and lowest estimated values for asymptotic body weight (C) for 3H and 5W were given by von Bertalanffy and Logistic model 4629.7 g for 2197.8 g respectively. The highest estimated parameter for maturating rate (b) was given by Logistic model 0.249 corresponds to the 2F and lowest in von Bertalanffy model 0.094 for 4Y. According to the coefficient of determination (R2) and mean square of error (MSE), Gompertz and von Bertalanffy models were suitable to describe the growth of Korean native chicken. Moreover, von Bertalannfy model was well described the most of KNC growth with biologically meaningful parameter compared to Gompertz model.

The production performance and egg quality traits among five strains of Korean native chickens (KNC) were evaluated in conventional cages. A total of 240 KNC were housed in a controlled environment. Each strain had 12 replicates with 4 chickens per cage. Feed intake, body weights, egg production and egg quality were measured at 24, 28 and 32 of weeks. Egg quality parameters were analyzed using 150 eggs. Results indicated significant (P 0.05) for feed efficiency. The difference among those KNC strains on egg shell color, egg shell strength and egg shell density were not different (P>0.05) at the age of week 24 while it was significant (P 0.05) on egg length and egg shape index from five strains of KNC. The significant difference (P 0.05) at the age of 32 weeks. Regarding internal quality parameters, albumen height and Haugh unit were significantly (P 0.05). Based on the egg weight and the production performance, GS-10 KNC strain was superior when compared with the other strains.

Although laser cladding process has been widely used to improve the wear and corrosion resistance, there are unwanted cracking issues during and/or after laser cladding. This study investigates the tendency of Co-based WC + NiCr composite layers to cracking during the laser cladding process. Residual stress distributions of the specimen are measured using neutron diffraction and elucidate the correlation between the residual stress and the cracking in three types of cylindrical specimens; (i) no cladding substrate only, (ii) cladding with 100% stellite#6, and (iii) cladding with 55% stellite#6 and 45% technolase40s. The microstructure of the clad layer was composed of Co-based dendrite and brittle eutectic phases at the dendritic boundaries. And WC particles were distributed on the matrix forming intermediate composition region by partial melting of the surface of particles. The overlaid specimen exhibited tensile residual stress, which was accumulated through the beads due to contraction of the coating layer generated by rapid solidification, while the non-clad specimen showed compressive. Also, the specimen overlaid with 55 wt% stellite#6 and 45 wt% technolase40s showed a tensile stress higher than the specimen overlaid with 100% stellite#6 possibly, due to the difference between thermal expansion coefficients of the matrix and WC particles. Such tensile stresses can be potential driving force to provide an easy crack path ways for large brittle fractures combined with the crack initiation sites such as the fractured WC particles, pores and solidification cracks. WC particles directly caused clad cracks by particle fracture under the tensile stress. The pores and solidification cracks also affected as initiation sites and provided an easy crack path ways for large brittle fractures.

The study was conducted to determine the effect of corssbred Korean native chickens (CKNC) on growth performance indices for hatch to 28 days. A total of 192 1-day-old birds were divided into one of 4 CKNC groups by 5 Korean native pure strains. Diets used in the study consisted of 2 phases with corn and soybean meal basis as earlier (1~2 weeks; crude protein 18.5%, metabolizable energy 3,000 kcal/kg), and grower (2~4 weeks; crude protein 15.0%, Metabolizable Energy 2,850 kcal/kg). Body weight and feed intake were measured bi-weekly. Crossbred 1G (group of family line) had higher body weight and average daily gain whereas crossbred 5Y had greater average daily feed intake and feed conversion ratio than other crossbred Korean native chicken for hatch to 28 days. The results in the current study indicated that crossbred 1G had higher growth performance indices compared with other crossbred Korean native chicken for hatch to 28 days.

Antibiotics in the diets for poultry were not only used for avoiding and (or) control bacterial infections but for promoting growth of the birds. However, there has been massive concerns of negative effects of antibiotics on human health such as development of antibiotics-resistance bacteria and (or) genes. Subsequently, some of countries (i.e., European Union member of country and South Korea) banned the use of antibiotics as growth promoters in the diets for livestock industries in 2006 and 2011, respectively. Thus, it has become important to develop feeding strategies and feed additives to control and reduce the occurrence of diseases in livestock without using in-feed antibiotics. In this review, therefore, it is attempted to gather information with respect to (1) understanding the digestive physiology and (2) knowledge pertaining to interaction linking feed additives and its physiological and metabolic responses in broiler chickens. Key words : additives, antibiotics, chickens, grwoth, feed

Addition of 1.5 wt.% Si into Fe–18Mn–0.6C steel noticeably increased the tendency of solidification cracking. Extensive segregation of Si at the dendritic and grain boundaries suppressed the formation of (Fe,Mn) 3 C eutectic carbide during solidification. On the other hand, Si segregation led to the formation of a metastable carbides consisting of a mixture of (Fe,Mn) 5 SiC and (Fe,Mn) 23 C 6 .

In the present study, the hot ductility behavior and hot cracking susceptibility of high manganese cast steel were investigated. Based on the 18Mn–0.6C alloy, a nickel was added for cryogenic impact toughness by maintaining the low temperature austenite stability to prevent strain induced martensitic transformation considering the appropriate stacking fault energy for mechanical twinning. A hot ductility test and Varestraint test were carried out to clarify the behavior of heat affected zone (HAZ) liquation and ductility dip cracking that were observed at the multi-pass weld heat affected zone of a nickel added high manganese weld metal for cryogenic uses. The heating and cooling rates were calculated by the three-dimensional Rosenthal׳s equation based on the actual welding heat input. A brittle temperature range, and a critical strain temperature range for each alloy showed no significant difference, but the overall ductility of the nickel added alloy was lower than the 18Mn alloy due to the lower degree of dynamic recrystallization by the higher stacking fault energy and the existence of the M3P/γ eutectic and MnS formed by the severe P segregation and higher S content, respectively. As a result of the longitudinal Varestraint test, the total and maximum HAZ crack length and cracked HAZ length of the nickel added alloy were larger than those of 18Mn alloy. The solid-state fracture, i.e. the ductility dip cracking was observed both in the on-cooling hot ductility tested and Varestraint tested alloys.

Numerous experiments have demonstrated that feeding a lower protein diet decreases protein fermentation in the gastrointestinal tract (GIT) and reduces the incidence of post-weaning diarrhea (PWD). However, there is a lack of holistic evidence underpinning the relationship between feeding a lower protein diet and PWD in relation to physiological responses and protein fermentation in the GIT. The scope of this article, therefore, will: (i) focus on the impact of dietary protein levels on selected indices of GIT health in weaned pigs without and with experimental infection with an enterotoxigenic strain of Escherichia coli; and (ii) attempt to conduct regression analysis to examine the relationships between dietary-origin protein intake, nitrogen fermentation indices, fecal consistency and the incidence of PWD. We used datasets generated from a series of four intensive experiments in weaned pigs. The collective results derived from these datasets indicate that restriction of daily protein intake to less than 60 g through feeding a lower protein diet for as little as 7 days after weaning reduced the incidence of PWD commensurate with a reduction in protein fermentation indices.

This study presents the mechanical properties of Fe–8Mn–0.06C steel welds, and examines local brittle zones in the heat affected zones of these steels. The microstructure of the base metal was composed primarily of lath martensite and a small amount of retained austenite. Mn segregation was also found along the thickness direction due to the banded structure of the rolled base metal. A significant local brittle zone (coarsened grained heat affected zone) and local hardness drop zone (subcritical heat affected zone) were observed in the weld heat affected zone. The Vickers hardness distribution measured from the weld metal to the base metal and Charpy V-notch toughness results revealed that decreases in hardness and toughness were more pronounced in the coarsened grained heat affected zone than in the fine-grained heat affected zone. A decrease in hardness was noticeable in the subcritical heat affected zone. The increases in hardness and toughness in the fine-grained heat affected zone relative to that of the coarsened grained heat affected zone were expected, due to the smaller martensite packet and block sizes. Further, the noticeable decrease in mechanical properties of the subcritical heat affected zone was strongly related to the formation of the austenite.

Pathogenic E. coli associated post-weaning diarrhea (PWD) and edema disease are common diseases in commercially-housed weanling pigs. An enterotoxigenic E. coli (ETEC) oral challenge model has been used to mimic the physiological responses observed in commercial conditions. However, an oral challenge procedure has two major limitations: (1) the ETEC cell density is unknown at the point of oral inoculation, and (2) blending ETEC with traditional TSB (trypticase soy broth) is not palatable and hence decreases acceptability by piglets. Therefore, the purposes of this study were to (1) establish a regression equation that can be used for estimation of ETEC concentration in dilution media using the spectrophotometric measurement of cell density; and (2) examine survival of ETEC after blending either with TSB, sweetener or dextrose. A strain of ETEC (serogroup beta-hemolytic E. coli O149; K91; F4; toxins LT, STa, STb) was grown in TSB for 3.5 hours, centrifuged, the supernatant was discarded, and the ETEC pellet was then blended either with TSB (100 mL), sweetener (60 mL TSB + 40 mL fruit flavored concentrate), or dextrose (50 mL TSB + 50 mL dextrose; 0.5g/mL dextrose). Cell density was measured using the colorimetric method and also plated on a 5% sheep blood agar for counting of ETEC colony forming units at 0, 5, 35, 65 and 125 min after blending. The optical density at 600 nm explained 83% of ETEC colony forming units, indicating that the established linear equation (y= 6E+08x ? 4E+07, P＜0.004) can be used for robust quantification of ETEC cell density in TSB, sweetener and dextrose media. When ETEC was blended with sweetener and dextrose, survival of ETEC was decreased by 45% and 72% within 5 min post-blending. Therefore, further research is required to find out the suitable medium that has potential to improve palatability without compromising survival of ETEC.

This study was conducted to examine the effect of alpha-lipoic acid with vitamin C and E on growth performance, intestinal morphology, and meat quality in broiler chickens under tropical conditions. A total of 288 one-day-old male ROSS 308 chicks (40±0.1 g) were used in a completely randomized design and allotted to one of six dietary treatments to form sixe replicates per treatment (eight birds per cage). The six dietary treatments were: a corn-soybean meal-based diet (NC; no antimicrobial compounds added) with 8 ppm alpha-lipoic acid (ALA); 150 ppm vitamin C and 75 ppm vitamin E (E-75); E-75 plus ALA (E-75-ALA); 150 ppm vitamin C and 50 ppm vitamin E (E-50) plus ALA (E-50-ALA); and 150 ppm vitamin C and 25 ppm vitamin E (E-25) plus ALA (E-25-ALA). All dietary treatments were continuously provided in liquid form, dissolved in water. Birds were housed in a battery cage (n = 36), and were offered dietary treatments on an ad libitum basis. The ambient temperature was maintained at 32±1 ºC for the first three weeks and reduced gradually to 28 ºC by the end of the experiment (day 35) to induce moderate tropical condition. One bird per pen (n = 6), and another bird per pen (n = 6) were euthanized via cervical dislocation to obtain terminal ileum to measure villus height and crypt depth at day 21, and to harvest breast meat and drumsticks to evaluate meat quality traits at day 35, respectively. Dietary treatment E-75-ALA improved body weight and average daily gain compared with birds fed other dietary treatments from day 1 to day 35. Birds fed dietary treatment E-75-ALA and E-50-ALA had higher villus height than those fed the other dietary treatments at day 21. Dietary treatments E-75-ALA and E-50-ALA reduced thiobarbituric acid reactive substance (TBARS) in drumsticks compared with other dietary treatments, but only treatment E-75-ALA decreased TBARS in breast meat at day 35. Liquid form of antioxidant compounds such as E-75-ALA can improve growth performance, histology of terminal ileum, and meat quality traits in broiler chickens under moderate tropical condition for 35 days.

This review provides an overview of the published data on the canola meal and its suitability for duck as an alternative plant-origin protein source to soybean meal. Canola meal is a legume origin protein source containing comparable amino acid profile to soybean meal and rich in essential minerals and vitamins. Nonetheless, it is known to contain less in energy content than soybean meal. Factors like field conditions and processing methods creates compositional variations among canola meal. Presence of anti-nutritional factors such as phenolic substances, phytate and glucosinolates which are known to reduce growth performance in livestock animals, are the major drawbacks for canola meal to be a competitive plant-origin protein source in the feed industry. This review is focused to address i) nutritional characteristics and feeding value of canola meal for ducks and ii) impacts of feeding canola meal on performances of ducks.

돼지를 이용한 이종간 장기 이식은 차세대 장기 공급 부족 문제를 해결해 줄 수 있는 가능성을 제공해준다. 그러나 돼지 장기를 이용한 이종간 장기 이식은 면역학적인 문제 외에도 가축 유래 전염성 병원균에 대한 안전성 문제가 심각하게 고려되어지고 있다. 대부분의 외인성 병원균은 무균 사육환경을 통해 제어되는 반면 내인성 레트로 바이러스(Endogenous Retrovirus, PERVs)는 germ line을 통해 전파됨으로 사육 조건으로 해결할 수는 없다. 본 연구는 이종간 장기 이식용 무균 돼지 생산시 가장 문제가 되는 PERVs에 대한 분포를 알아보고자 국내 돼지(Landrace, Berkshire, Yorkshire, Duroc)의 genome 내 PERVs 분포와 유전자 염기 서열을 비교하였다. 모든 공시 돼지(20두)의 genomic DNA로부터 PCR을 이용하여 PERV A/B/C와 PERV-E의 존재를 확인하였다. pol 유전자 일부 염기 서열 분석 결과 같은 품종내 개체간 또는 품종간 상동성이 99.1과 98.8%로 매우 높게 나왔다. 본 연구의 결과 모든 국내 돼지 유전자내에 PERV A/B/C와 PERV E가 provirus 형태로 많이 존재하며 바이러스간의 높은 상동성은 바이러스 제어에 많은 잇점으로 작용하리라 사료되며 아직 밝혀지지 않은 내인성바이러스에 대한 연구가 요구되어진다. 그러므로 본 연구의 자료는 이종간 장기 이식용 무균돼지 생산 시 PERVs 를 제어하기 위한 기초 자료로 활용될 수 있을 것으로 사료된다. 【Xenotransplantation of porcine organs has the potential to overcome the severe. shortage of human tissues and organs available for human transplantation. The swine represents an ideal source of such organs because of their plentiful supply and their numerous anatomical and physiological similarities to the human. However, this procedure also carries with a number of safety issues relating to the zoonotic infections. Porcine endogenous retrovinJses(PERVs), \Wich are germ line transmitted and persist without symptoms in the pigs, are most concerning zoonotic viroses. In order to analyze the prevalence of PERV in domestic pigs, four kinds of pigs'(Landrace, Berkshire, Yorkshire, and Duroc) genomic DNA were isolated from their hair follicles. PCR analysis was carried out for detection of PERVs using subgroup A/B/C and E pol sequence primers. All pigs (20 heads) tested had high copy number of PERVs within genomes. Subgroup A/B/C and E pol gene sequences from 20 isolates were determined by direct sequencing. Sequence analysis showed pol sequences are highly conserved among intra- and inter-subspecies(99.l and 98.8%, respectively). As a first report of PERV prevalence in Korea pigs, our data would be the basic concepts of PERV transmission study in xenotransplantation.】

Numerous experiments have demonstrated that feeding a lower protein diet decreases protein fermentation in the gastrointestinal tract (GIT) and reduces the incidence of post-weaning diarrhea (PWD). However, there is a lack of holistic evidence underpinning the relationship between feeding a lower protein diet and PWD in relation to physiological responses and protein fermentation in the GIT. The scope of this article, therefore, will: (i) focus on the impact of dietary protein levels on selected indices of GIT health in weaned pigs without and with experimental infection with an enterotoxigenic strain of Escherichia coli; and (ii) attempt to conduct regression analysis to examine the relationships between dietary-origin protein intake, nitrogen fermentation indices, fecal consistency and the incidence of PWD. We used datasets generated from a series of four intensive experiments in weaned pigs. The collective results derived from these datasets indicate that restriction of daily protein intake to less than 60 g through feeding a lower protein diet for as little as 7 days after weaning reduced the incidence of PWD commensurate with a reduction in protein fermentation indices.

This review provides an overview of the published data on the canola meal and its suitability for duck as an alternative plant-origin protein source to soybean meal. Canola meal is a legume origin protein source containing comparable amino acid profile to soybean meal and rich in essential minerals and vitamins. Nonetheless, it is known to contain less in energy content than soybean meal. Factors like field conditions and processing methods creates compositional variations among canola meal. Presence of anti-nutritional factors such as phenolic substances, phytate and glucosinolates which are known to reduce growth performance in livestock animals, are the major drawbacks for canola meal to be a competitive plant-origin protein source in the feed industry. This review is focused to address i) nutritional characteristics and feeding value of canola meal for ducks and ii) impacts of feeding canola meal on performances of ducks.