A numerical study on mixed convection in a lid-driven cavity with a circular cylinder

G. F. Zheng,하만영,윤현식,Y. G. Park 대한기계학회 2013 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.27 No.1

A two-dimensional numerical simulation is carried out in this study to investigate mixed convection in a lid-driven cavity with an isothermal circular cylinder. The simulation is conducted at three Reynolds numbers of Re = 100, 500, and 1000 under a fixed Grashof number of Gr = 105. The top wall of the cavity moves to the right at a constant velocity and is kept at a low temperature of Tc, whereas the stationary bottom wall is kept at a constant high temperature of Th. The immersed-boundary method, which is based on the finite volume method, is adopted for the boundary of the circular cylinder that is present in the square cavity. The present study aims to investigate the effects of circular cylinder on fluid flow and heat transfer in a cavity at different locations. The fluid flow and heat transfer characteristics in the cavity strongly depend on the position of the circular cylinder as well as on the relative magnitude of the forced convection and the natural convection caused by the movement in the top wall of the cavity and the heating at the hot bottom wall, respectively.

New Evidence of Alleles (V199I and G52S) at the PRKAG3 (RN) Locus Affecting Pork Meat Quality

Chen, J.F.,Dai, L.H.,Peng, J.,Li, J.L.,Zheng, R.,Zuo, B.,Li, F.E.,Liu, M.,Yue, K.,Lei, M.G.,Xiong, Y.Z.,Deng, C.Y.,Jiang, S.W. Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.4

The porcine PRKAG3 (RN) gene encodes the regulatory gamma subunit of adenosine monophosphate-activated protein kinase (AMPK), which is a good candidate gene affecting meat quality. In this study, the effects of two missense mutations A595G (Ile199Val) and G154A (Gly52Ser) in porcine PRKAG3 gene on meat quality traits were studied in M. Longissimus dorsi (LD), M. Semispinalis capitis (SC) and M. Biceps femoris (BF) from different populations of 326 pigs. The PRKAG3 alleles 199I, 199IV, 52S and 52G were identified with PCR-RFLPs and all genotypes - 199I/199I, 199I/199V, 199V/199V, 52S/52S, 52S/52G and 52G/52G - were found. The frequency of V allele was larger than that of I allele in all populations. I allele frequency was zero in Chinese Meishan pigs (population D) especially. G allele frequency was larger than that of S allele in all populations except Large White (population A). Both variations at the PRKAG3 locus significantly affected these meat quality traits. The pork meat quality has not previously been established in Meishan or crosses thereof. The results suggested that generally pH of LD, SC and BF was higher in Meishan pigs than that in other populations. Moreover, Meishan pigs showed higher water-holding capacity and intramuscular fat (IMF), lower water content and water loss percentage compared to other populations in terms of the two variations. The results present here supply new evidence that alleles V199I and G52S at the PRKAG3 locus affect pork meat quality and provide useful information on pork production.

Sequencing, Genomic Structure, Chromosomal Mapping and Association Study of the Porcine ADAMTS1 Gene with Litter Size

Yue, K.,Peng, J.,Zheng, R.,Li, J.L.,Chen, J.F.,Li, F.E.,Dai, L.H.,Ding, SH.H.,Guo, W.H.,Xu, N.Y.,Xiong, Y.ZH.,Jiang, S.W. Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.7

A disintegrin-like and metalloprotease (reprolysin type) with thrombospondin type 1 motif (ADAMTS1) plays a critical role in follicular rupture and represents a major advance in the proteolytic events that control ovulation. In this study, a 9,026-bp DNA sequence containing the full coding region, all 8 introns and part of the 5'and 3' untranslated region of the porcine ADAMTS1 gene was obtained. Analysis of the ADAMTS1 gene using the porcine radiation hybrid panel indicated that pig ADAMTS1 is closely linkage with microsatellite marker S0215, located on SSC13q49. The open reading frame of its cDNA covered 2,844 bp and encoded 947 amino acids. The coding region of porcine ADAMTS1 as determined by sequence alignments shared 85% and 81% identity with human and mouse cDNAs, respectively. The deduced protein contained 947 amino acids showing 85% sequence similarity both to the human and mouse proteins, respectively. Comparative sequencing of three pig breeds revealed one single nucleotide polymorphism (SNP) within exon 7 of which a G-C substitution at position 6006 changes a codon for arginine into a codon for proline. The substitution was situated within a PvuII recognition site and developed as a PCR-RFLP marker for further use in population variation investigations and association analysis with litter size. Allele frequencies of this SNP were investigated in seven pig breeds/lines. An association analysis in a new Qingping female line suggested that different ADAMTS1 genotypes have significant differences in litter size (p<0.01).

Burden of Total and Cause-Specific Mortality Related to Tobacco Smoking among Adults Aged ≥45 Years in Asia: A Pooled Analysis of 21 Cohorts

Zheng, Wei,McLerran, Dale F.,Rolland, Betsy A.,Fu, Zhenming,Boffetta, Paolo,He, Jiang,Gupta, Prakash Chandra,Ramadas, Kunnambath,Tsugane, Shoichiro,Irie, Fujiko,Tamakoshi, Akiko,Gao, Yu-Tang,Koh, Woon Public Library of Science 2014 PLoS medicine Vol.11 No.4

<▼1><P>Wei Zheng and colleagues quantify the burden of tobacco-smoking-related deaths for adults in Asia.</P><P><I>Please see later in the article for the Editors' Summary</I></P></▼1><▼2><P><B>Background</B></P><P>Tobacco smoking is a major risk factor for many diseases. We sought to quantify the burden of tobacco-smoking-related deaths in Asia, in parts of which men's smoking prevalence is among the world's highest.</P><P><B>Methods and Findings</B></P><P>We performed pooled analyses of data from 1,049,929 participants in 21 cohorts in Asia to quantify the risks of total and cause-specific mortality associated with tobacco smoking using adjusted hazard ratios and their 95% confidence intervals. We then estimated smoking-related deaths among adults aged ≥45 y in 2004 in Bangladesh, India, mainland China, Japan, Republic of Korea, Singapore, and Taiwan—accounting for ∼71% of Asia's total population. An approximately 1.44-fold (95% CI = 1.37–1.51) and 1.48-fold (1.38–1.58) elevated risk of death from any cause was found in male and female ever-smokers, respectively. In 2004, active tobacco smoking accounted for approximately 15.8% (95% CI = 14.3%–17.2%) and 3.3% (2.6%–4.0%) of deaths, respectively, in men and women aged ≥45 y in the seven countries/regions combined, with a total number of estimated deaths of ∼1,575,500 (95% CI = 1,398,000–1,744,700). Among men, approximately 11.4%, 30.5%, and 19.8% of deaths due to cardiovascular diseases, cancer, and respiratory diseases, respectively, were attributable to tobacco smoking. Corresponding proportions for East Asian women were 3.7%, 4.6%, and 1.7%, respectively. The strongest association with tobacco smoking was found for lung cancer: a 3- to 4-fold elevated risk, accounting for 60.5% and 16.7% of lung cancer deaths, respectively, in Asian men and East Asian women aged ≥45 y.</P><P><B>Conclusions</B></P><P>Tobacco smoking is associated with a substantially elevated risk of mortality, accounting for approximately 2 million deaths in adults aged ≥45 y throughout Asia in 2004. It is likely that smoking-related deaths in Asia will continue to rise over the next few decades if no effective smoking control programs are implemented.</P><P><I>Please see later in the article for the Editors' Summary</I></P></▼2><▼3><P><B>Editors' Summary</B></P><P><B>Background</B></P><P>Every year, more than 5 million smokers die from tobacco-related diseases. Tobacco smoking is a major risk factor for cardiovascular disease (conditions that affect the heart and the circulation), respiratory disease (conditions that affect breathing), lung cancer, and several other types of cancer. All told, tobacco smoking kills up to half its users. The ongoing global “epidemic” of tobacco smoking and tobacco-related diseases initially affected people living in the US and other Western countries, where the prevalence of smoking (the proportion of the population that smokes) in men began to rise in the early 1900s, peaking in the 1960s. A similar epidemic occurred in women about 40 years later. Smoking-related deaths began to increase in the second half of the 20th century, and by the 1990s, tobacco smoking accounted for a third of all deaths and about half of cancer deaths among men in the US and other Western countries. More recently, increased awareness of the risks of smoking and the introduction of various tobacco control measures has led to a steady decline in tobacco use and in smoking-related diseases in many developed countries.</P><P><B>Why Was This Study Done?</B></P><P>Unfortunately, less well-developed tobacco control programs, inadequate public awareness of smoking risks, and tobacco company marketing have recently led to sharp increases in the prevalence of smoking in many low- and middle-income countries, particularly in Asia. More than 50% of men in many Asian countries are now smokers, about tw

Genetic Polymorphism of Milk Protein and Their Relationships with Milking Traits in Chinese Yak

Mao, Y.J.,Zhong, G.H.,Zheng, Y.C.,Pen, X.W.,Yang, Z.P.,Wang, Y.,Jiang, M.F. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.11

Milk protein polymorphisms were genotyped by polyacrylamide gel electrophoresis (PAGE) from 109 Maiwa and 100 Jiulong yaks. The relationships between milk protein polymorphisms and 3 milking traits were studied. The results showed that $\beta$-CN, $\kappa$-CN and $\alpha$-La were monomorphic, and ${\alpha}_{s1}$-CN and $\beta$-Lg were polymorphic, with ${\alpha}_{s1}$-CN D and $\beta$-Lg E as dominant genes, respectively. The frequencies of ${\alpha}_{s1}$-CN D were 0.8073 and 0.6000 in two populations and $\beta$-Lg E were 0.9770 and 0.9700. The mean heterozygosities were 0.1021 and 0.1867 in the two populations. No significant effects on milking traits and milk protein compositions were observed except for ${\alpha}_{s1}$-CN locus on fat percentage in Jiulong yak.

Effects of Isoleucine Supplementation of a Low Protein, Corn-Soybean Meal Diet on the Performance and Immune Function of Weanling Pigs

Zheng, C.T.,Li, D.F.,Qiao, S.Y.,Gong, L.M.,Zhang, D.F.,Thacker, P.,Han, In K. Asian Australasian Association of Animal Productio 2001 Animal Bioscience Vol.14 No.1

This experiment was conducted to investigate the effects of crystalline isoleucine supplementation of a low protein, corn-soybean meal diet on the performance and immune function of weanling pigs. Forty-five crossbred ($Duroc{\times}Landrace{\times}Large\;White$) piglets, weighing an average of $11.00{\pm}0.07kg$, were assigned to either a control diet containing 20% crude protein (0.64% isoleucine), a 16% crude protein diet without isoleucine supplementation (0.41% isoleucine) or a 16% crude protein diet supplemented with isoleucine (0.64% isoleucine). Reducing the crude protein content of the diet from 20 to 16% significantly (p<0.05) reduced both average daily gain and feed intake. Feed conversion also tended (p=0.07) to be poorer for a low protein diet without isoleucine supplementation. Isoleucine supplementation of the 16% crude protein diet increased both gain and feed intake to a level similar to that obtained by pigs fed the 20% crude protein diet (p>0.05). Blood urea nitrogen, serum total protein and serum globulin were significantly (p<0.05) higher for pigs fed the unsupplemented 16% crude protein diet than for pigs fed the isoleucine-supplemented diet or the control. Egg albumin antibody titre decreased significantly (p<0.05) in pigs fed the diet with isoleucine supplementation, whereas the antibody titre of pigs fed the low protein and low isoleucine diet was similar to that of pigs fed the diet containing 20% crude protein and 0.64% isoleucine. It was suggested that crystalline isoleucine supplementation of a low protein and low isoleucine diet improved pig performance but suppressed humoral immune function.

Effects of Alfalfa Meal on Growth Performance and Gastrointestinal Tract Development of Growing Ducks

Jiang, J.F.,Song, X.M.,Huang, X.,Zhou, W.D.,Wu, J.L.,Zhu, Z.G.,Zheng, H.C.,Jiang, Y.Q. Asian Australasian Association of Animal Productio 2012 Animal Bioscience Vol.25 No.10

A study was conducted to evaluate effects of alfalfa meal on growth performance and gastrointestinal tract development of growing layer ducks to provide evidence for application of alfalfa meal in the duck industry. Two hundred and fifty-six healthy Shaoxing 7-wk old growing layer ducks were selected and randomly allocated to 1 of 4 dietary treatments based on corn and soybean meal and containing 0, 3, 6, and 9% of alfalfa meal for 8 wks. Each treatment consisted of 4 replicates of 16 ducks each. Briefly, birds were raised in separate compartments, and each compartment consisted of three parts: indoor floor house, adjacent open area and a connecting water area. The results showed: i) Growing ducks fed alfalfa meal diet were not significantly different in average daily gain, feed intake and gain-to-feed ratio from those fed no alfalfa diet (p>0.05). ii) Alfalfa meal increased the ratio crop, gizzard to live weight, caecum to live weight, the caecum index of growing ducks (p<0.05). iii) Villus height in duodenum and jejunum of growing ducks increased significantly with the increase of alfalfa meal levels (p<0.05). Crypt depth in duodenum and jejunum of growing ducks decreased significantly with the increase of alfalfa meal levels (p<0.05). This experiment showed that feeding of alfalfa meal to growing layer ducks could improve gastrointestinal tract growth and small intestinal morphology without effect on performance. This experiment provides evidence that alfalfa meal is a very valuable feedstuff for growing layer ducks.

Oviduct-specific Glycoprotein 1 Locus is Associated with Litter Size and Weight of Ovaries in Pigs

Niu, B.Y.,Xiong, Y.Z.,Li, F.E.,Jiang, S.W.,Deng, C.Y.,Ding, S.H.,Guo, W.H.,Lei, M.G.,Zheng, R.,Zuo, B.,Xu, D.Q.,Li, J.L. Asian Australasian Association of Animal Productio 2006 Animal Bioscience Vol.19 No.5

Oviduct-specific glycoprotein 1 (OVGP1) is implicated in playing a role in fertilization and early embryo development. In this study, we have obtained the sequence of intron 9 of OVGP1 gene in swine. Comparative sequencing of Meishan (a native Chinese breed) and Large White pig breeds revealed an A/T substitution at position 943. A PCR-EcoRI-RFLP assay was developed to detect this mutation. Polymorphism analysis in Qingping animals showed that pigs with BB genotype had lower number of piglets born alive (NBA) in multiple parities than pigs with AA (p<0.05) and AB genotype (p<0.01). In Large $White{\times}Meishan$ ($LW{\times}M$) $F_2$ offspring, the weight of both ovaries (OW) of the BB genotype was significantly lighter than that of AB (p = 0.05) and AA (p<0.01) genotypes. Analysis of the data also revealed that the mutation locus affected these two traits mostly by additive effects. These studies indicated that the polymorphism was associated with NBA and OW in two distinct populations and further investigations in more purebreds or crossbreds are needed to confirm these results.

Characterization of electrodeposited Ni-Fe-SiC alloys for microelectromechanical applications

Zheng, X.,Chen, X.,Gu, F.,Liu, Y.,Lee, D.-W. American Vacuum Society 2010 Journal of Vacuum Science & Technology. B Vol.28 No.6

Partial cooperative spectrum sensing schedule in cognitive network

Xu, F.,Zheng, X.,Li, X.,Zhou, Z. SPRINGER SCIENCE + BUSINESS MEDIA 2009 Science China Information Sciences Vol.52 No.12