True Digestibility of Phosphorus in Different Resources of Feed Ingredients in Growing Pigs

Wu, X.,Ruan, Z.,Zhang, Y.G.,Hou, Y.Q.,Yin, Y.L.,Li, T.J.,Huang, R.L.,Chu, W.Y.,Kong, X.F.,Gao, B.,Chen, L.X. Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.1

To determine the true digestible phosphorus (TDP) requirement of growing pigs, two experiments were designed with the experimental diets containing five true digestible P levels (0.16%, 0.20%, 0.23%, 0.26% and 0.39%) and the ratio of total calcium to true digestible P (TDP) kept at 2:1. In Experiment 1, five barrows (Duroc${\times}$Landrace${\times}$Yorkshire) with an average initial body weight of 27.9 kg were used in a $5{\times}5$ Latin-square design to evaluate the effect of different dietary P levels on the digestibility and output of P and nitrogen. In Experiment 2, sixty healthy growing pigs (Duroc${\times}$Landrace${\times}$Yorkshire) with an average body weight (BW) of 21.4 kg were assigned randomly to one of the five dietary treatments (12 pigs/diet), and were used to determine the true digestible phosphorus (TDP) requirement of growing pigs on the basis of growth performance and serum biochemical indices. The results indicated that the true digestibility of P increased (p<0.05) linearly with increasing dietary TDP level below 0.26%. The true P digestibility was highest (56.6%) when dietary TDP was 0.34%. Expressed as g/kg dry matter intake (DMI), fecal P output increased (p<0.05) linearly with increasing P input. On the basis of g/kg fecal dry matter (DM), fecal P output was lowest for Diet 4 and highest (p<0.05) for Diet 5. The apparent digestibility of crude protein (CP) did not differ (p>0.05) among the five diets, with the average nitrogen output of 12.14 g/d and nitrogen retention of 66% to 74% (p>0.05), which suggested that there was no interaction between dietary P and CP protein levels. During the 28-d experimental period of Experiment 2, the average daily gain (ADG) of pigs was affected by dietary TDP levels as described by Eq. (1): $y=-809,532x^4+788,079x^3-276,250x^2+42,114x-1,759$; ($R^2=0.99$; p<0.01; y = ADG, g/d; x = dietary TDP, %), F/G for pigs by Eq. (2): $y=3,651.1x^4-3,480.4x^3+1,183.8x^2-172.5x+10.9$ ($R^2=0.99$; p<0.01; y = F/G; x = dietary TDP, %), and Total P concentrations in serum by Eq. (3): $y=-3,311.7x^4+3,342.7x^3-1,224.6x^2+195.6x-8.7$ (R2 = 0.99; p<0.01; y = total serum P concentration and x = dietary TDP, %). The highest ADG (782 g/d), the lowest F/G (1.07) and the highest total serum P concentration (3.1 mmol/L) were obtained when dietary TDP level was 0.34%. Collectively, these results indicate that the optimal TDP requirement of growing pigs is 0.34% of the diet at a total Ca to TDP ratio of 2:1.

Investigating energy partitioning during photosynthesis using an expanded quantum yield convention

Ahn, T.K.,Avenson, T.J.,Peers, G.,Li, Z.,Dall'Osto, L.,Bassi, R.,Niyogi, K.K.,Fleming, G.R. Elsevier Science Publishers [etc.] 2009 Chemical physics Vol.357 No.1

In higher plants, regulation of excess absorbed light is essential for their survival and fitness, as it enables avoidance of a build up of singlet oxygen and other reactive oxygen species. Regulation processes (known as non-photochemical quenching; NPQ) can be monitored by steady-state fluorescence on intact plant leaves. Pulse amplitude modulated (PAM) measurements of chlorophyll a fluorescence have been used for over 20 years to evaluate the amount of NPQ and photochemistry (PC). Recently, a quantum yield representation of NPQ (Φ<SUB>NPQ</SUB>), which incorporates a variable fraction of open reaction centers, was proposed by Hendrickson et al. [L. Hendrickson, R.T. Furbank, W.S. Chow, Photosynth. Res. 82 (2004) 73]. In this work we extend the quantum yield approach to describe the yields of reversible energy-dependent quenching (Φ<SUB>qE</SUB>), state transitions to balance PC between photosystems II and I (Φ<SUB>qT</SUB>), and photoinhibition quenching associated with damaged reaction centers (Φ<SUB>qI</SUB>). We showed the additivity of the various quantum yield components of NPQ through experiments on wild-type and npq1 strains of Arabidopsis thaliana. The quantum yield approach enables comparison of Φ<SUB>qE</SUB> with data from a variety of techniques used to investigate the mechanism of qE. We showed that Φ<SUB>qE</SUB> for a series of A. thaliana genotypes scales linearly with the magnitude of zeaxanthin cation formation, suggesting that charge-transfer quenching is largely responsible for qE in plants.

New Evidences of Effect of Melanocortin-4 Receptor and Insulin-like Growth Factor 2 Genes on Fat Deposition and Carcass Traits in Different Pig Populations

Chen, J.F.,Xiong, Y.Z.,Zuo, B.,Zheng, R.,Li, F.E.,Lei, M.G.,Li, J.L.,Deng, C.Y.,Jiang, S.W. Asian Australasian Association of Animal Productio 2005 Animal Bioscience Vol.18 No.11

The Melanocortin-4 Receptor (MC4R) and Insulin-like Growth Factor 2 (IGF2) are two important candidate genes related to fat deposition and carcass traits. MC4R was found on study on human obesity and then was studied as candidate gene affecting food intake and fat deposition traits in mice and pigs. Insulin-like Growth Factor 2 (IGF2) gene plays an important role on tumor cell proliferation and muscle growth. It also affects fat traits and live weight in pigs. In this paper, MC4R and IGF2 were studied as two candidate genes associated with important economic traits such as fat deposition and carcass traits in five different pig populations. Taq I-PCR-RFLP and Bcn I-PCR-RFLP were respectively used to detect the polymorphism of genotypes of MC4R and IGF2 genes. Different MC4R genotype frequencies were observed in four populations. IGF2 genotype frequencies were also different in two populations. The results of association analysis show both MC4R and IGF2 genes were significantly associated with fat deposition and carcass traits in about 300 pigs. This work will add new evidence of MC4R and IGF2 affecting fat deposition and carcass traits in pigs and show that two genes can be used as important candidate genes for marker assistant selection (MAS) of growth and lean meat percentage in pigs.

Probabilistic fatigue life prediction methodology for notched components based on simple smooth fatigue tests

Z. R. Wu,X. T. Hu,Z. X. Li,P. P. Xin,Y. D. Song 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.1

The methodology of probabilistic fatigue life prediction for notched components based on smooth specimens is presented. Weakestlink theory incorporating Walker strain model has been utilized in this approach. The effects of stress ratio and stress gradient have been considered. Weibull distribution and median rank estimator are used to describe fatigue statistics. Fatigue tests under different stress ratios were conducted on smooth and notched specimens of titanium alloy TC11. The proposed procedures were checked against the test data of TC11 notched specimens. Prediction results of 50 % survival rate are all within a factor of two scatter band of the test results.

Intramuscular Administration of Zinc Metallothionein to Preslaughter Stressed Pigs Improves Anti-oxidative Status and Pork Quality

Li, L.L.,Hou, Z.P.,Yin, Y.L.,Liu, Y.H.,Hou, D.X.,Zhang, B.,Wu, G.Y.,Kim, S.W.,Fan, M.Z.,Yang, C.B.,Kong, X.F.,Tang, Z.R.,Peng, H.Z.,Deng, D.,Deng, Z.Y.,Xie, M.Y.,Xiong, H.,Kang, P.,Wang, S.X. Asian Australasian Association of Animal Productio 2007 Animal Bioscience Vol.20 No.5

This study was conducted to determine the effects of exogenous zinc-metallothionein (Zn-MT) on anti-oxidative function and pork quality. After feeding a corn-soybean meal-based diet for two weeks, 48 pigs ($Duroc{\times}Landrace{\times}Chinese\;Black Pig$) were assigned randomly to four groups. Pigs in Group 1 were maintained under non-stress conditions, whereas pigs in Groups 2, 3 and 4 were aggressively handled for 25 min to produce stress. Pigs in Groups 1, 2, 3, and 4 received intramuscular administration of saline (control group; CON), 0 (negative control group; NCON), 0.8 (low dose group; LOW), and 1.6 (high dose group; HIGH) mg rabbit liver Zn-MT per kg body weight, respectively. Pigs were slaughtered at 3 and 6 h post-injection. Zn-MT treatment increased (p<0.05) the activities of superoxide dismutase (SOD) and glutathione-peroxidase (GSH-PX) while decreasing the concentration of malondialdehyde (MDA) in liver. These responses were greater (p<0.05) at 6 h than at 3 h post Zn-MT injection. Zn-MT treatment increased (p<0.05) hepatic SOD mRNA levels in a time and dose-dependent manner and decreased (p<0.05) serum glutamate-pyruvate transaminase and lactate dehydrogenase activities (indicators of tissue integrity). Zn-MT administration decreased (p<0.05) lactate concentration and increased (p<0.05) pH and water-holding capacity in the longissimus thorasis meat. Collectively, our results indicate that intramuscular administration of Zn-MT to pre-slaughter stressed pigs improved tissue anti-oxidative ability and meat quality.

Damage and vibrations of nuclear power plant buildings subjected to aircraft crash part II: Numerical simulations

Li, Z.R.,Li, Z.C.,Dong, Z.F.,Huang, T.,Lu, Y.G.,Rong, J.L.,Wu, H. Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.9

Investigations of large commercial aircraft impact effect on nuclear power plant (NPP) buildings have been drawing extensive attentions, particularly after the 9/11 event, and this paper aims to numerically assess the damage and vibrations of NPP buildings subjected to aircrafts crash. In Part I of present paper, two shots of reduce-scaled model test of aircraft impact on NPP were conducted based on the large rocket sled loading test platform. In the present part, the numerical simulations of both scaled and prototype aircraft impact on NPP buildings are further performed by adopting the commercial program LS-DYNA. Firstly, the refined finite element (FE) models of both scaled aircraft and NPP models in Part I are established, and the model impact test is numerically simulated. The validities of the adopted numerical algorithm, constitutive model and the corresponding parameters are verified based on the experimental NPP model damages and accelerations. Then, the refined simulations of prototype A380 aircraft impact on a hypothetical NPP building are further carried out. It indicates that the NPP building can totally withstand the impact of A380 at a velocity of 150 m/s, while the accompanied intensive vibrations may still lead to different levels of damage on the nuclear related equipment. Referring to the guideline NEI07-13, a maximum acceleration contour is plotted and the shock damage propagation distances under aircraft impact are assessed, which indicates that the nuclear equipment located within 11.5 m from the impact point may endure malfunction. Finally, by respectively considering the rigid and deformable impacts mainly induced by aircraft engine and fuselage, an improved Riera function is proposed to predict the impact force of aircraft A380.

An automated focusing method for a parallel micro-manipulator alignment

Li, Z. Y.,Ihn, Y. S.,Choi, H. R.,Moon, H.,Koo, J. C. Springer Science + Business Media 2016 Microsystem Technologies Vol.22 No.6

<P>In this work, particle swarm optimization (PSO) algorithm is employed to align spot array and judging image sharpness with auto-focusing (AF) image evaluation function. To satisfy the requirement of optical alignment system, a high precision manipulator has to be developed. Applied parallel manipulator that consists of four 2-degree of freedom (DOF) decoupled actuator gives chances to provide 6-DOF independence motion, and has strength in high accuracy. This paper covers the follows: Firstly, motivation of this development for the digital mirror device (DMD) based maskless lithography system to introduce spot array method in maskless digital exposure process. Secondly, in order to precisely control moving platform, applying a redundant parallel micro-manipulator. Thirdly, proposing a suitable error model of the system and applying the PSO and Z axis auto-focusing algorithm to align spot array concerning position correction. Finally, we designed experiment which is applied a vision sensor and alignment unit to verify proposed positioning algorithm. Experimental result will be shown that proposed can solve the alignment problem by reducing the position error of the system.</P>

Field dependence of antiferromagnetic domain switching in epitaxial Fe/CoO/MgO(001) systems

Li, Q.,Ma, T. P.,Yang, M.,Sun, L.,Huang, S. Y.,Li, R. W.,Won, C.,Qiu, Z. Q.,Wu, Y. Z. American Physical Society 2017 Physical Review B Vol.96 No.2

<P>Utilizing the magneto-optic Kerr effect and Kerr microscopy measurements, we investigated the antiferro-magnetic (AFM) domain switching process at different magnetic fields in a single-crystalline Fe/CoO bilayer grown on MgO(001) substrate. In spite of the zero-net magnetic moment in the CoO layer, we find that the activation energy barrier of CoO AFM domain switching decreased at larger magnetic field. To separate the different behaviors of domain nucleation and domain wall motion during the CoO spin switching process, a new analytical method was developed. Using this method, we found that the CoO domain nucleation energy barrier exhibited a jump at a critical magnetic field while the CoO domain wall motion experienced only a tiny energy barrier variation. The field-dependent behaviors of the energy barriers were attributed to the formation of a spiral domain wall in the Fe layer during its magnetization reversal and this was supported by micromagnetic simulations.</P>

Nutrition knowledge, attitude and practice on prevention of childhood obesity in parents of preschool children in Chengdu, China

R Li,Z Jiguo,L Guangli,X Danqi,Z Guo 대한지역사회영양학회 2004 Journal of community nutrition Vol.6 No.3

Damage and vibrations of nuclear power plant buildings subjected to aircraft crash part I: Model test

Li, Z.R.,Li, Z.C.,Dong, Z.F.,Huang, T.,Lu, Y.G.,Rong, J.L.,Wu, H. Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.9

Investigations of large commercial aircraft impact effect on nuclear power plant (NPP) buildings have been drawing extensive attentions, particularly after the 9/11 event, and this paper aims to experimentally assess the damage and vibrations of NPP buildings subjected to aircraft crash. In present Part I, two shots of reduce-scaled model test of aircraft impacting on NPP building were carried out. Firstly, the 1:15 aircraft model (weighs 135 kg) and RC NPP model (weighs about 70 t) are designed and prepared. Then, based on the large rocket sled loading test platform, the aircraft models were accelerated to impact perpendicularly on the two sides of NPP model, i.e., containment and auxiliary buildings, with a velocity of about 170 m/s. The strain-time histories of rebars within the impact area and acceleration-time histories of each floor of NPP model are derived from the pre-arranged twenty-one strain gauges and twenty tri-axial accelerometers, and the whole impact processes were recorded by three high-speed cameras. The local penetration and perforation failure modes occurred respectively in the collision scenarios of containment and auxiliary buildings, and some suggestions for the NPP design are given. The maximum acceleration in the 1:15 scaled tests is 1785.73 g, and thus the corresponding maximum resultant acceleration in a prototype impact might be about 119 g, which poses a potential threat to the nuclear equipment. Furthermore, it was found that the nonlinear decrease of vibrations along the height was well reflected by the variations of both the maximum resultant vibrations and Cumulative Absolute Velocity (CAV). The present experimental work on the damage and dynamic responses of NPP structure under aircraft impact is firstly presented, which could provide a benchmark basis for further safety assessments of prototype NPP structure as well as inner systems and components against aircraft crash.