Numerical solution for multiple confocal elliptic dissimilar cylinders

Y. Z. Chen 국제구조공학회 2017 Smart Structures and Systems, An International Jou Vol.19 No.2

This paper provides a numerical solution for multiple confocal elliptic dissimilar cylinders. In the problem, the inner elliptic notch is under the traction free condition. The medium is composed of many confocal elliptic dissimilar cylinders. The transfer matrix method is used to study the continuity condition for the stress and displacement along the interfaces. Two cases, or the infinite matrix case and the finite matrix case, are studied in this paper. In the former case, the remote tension is applied in y- direction. In the latter case, the normal loading is applied along the exterior elliptic contour. For two cases, several numerical results are provided.

Evaluation of Elastic In-plane Flexural Rigidity of Unstiffened Multiplanar CHS X-joints

L. J. Jia,Y. Y. Chen 한국강구조학회 2014 International Journal of Steel Structures Vol.14 No.1

Tubular structures have been widely applied in offshore structures and civil buildings in past decades. Some research has beencarried out on rigidity of unstiffened circular hollow section (CHS) joints with various types, e.g. T-, Y-, K- and X-joints byformer researchers. However, limited investigations on the in-plane flexural rigidity of multiplanar CHS X-joints which arecommonly used in single-layered latticed structures are found in available literatures. In this paper, first a finite element modelwas calibrated through comparison with test results, and then a numerical parametric study on elastic axial rigidity ofmultiplanar unstiffened CHS X-joints was carried out using the calibrated models with package ABAQUS. Based on theparametric results, an in-plane flexural rigidity formula for the joints was fitted. Finally, a comparison among the differentformulae in predicting joint rigidity of unstiffened CHS X-joints was carried out, which indicated a good reliability of theproposed formula.

A Phase 3 Evaluation of Daclatasvir plus Asunaprevir in Treatment-Naive Patients with Chronic HCV Genotype 1b Infection

( L. Wei ),( F. Wang ),( M. Zhang ),( J. Jia ),( A.A. Yakovlev ),( W. Xie ),( E.Z. Burnevich ),( J. Niu ),( Y.J. Jung ),( X. Jiang ),( M. Xu ),( X. Chen ),( Q. Xie ),( J. Li ),( J. Hou ),( H. Tang ),( 대한간학회 2017 춘·추계 학술대회 (KASL) Vol.2017 No.1

Background/Aims: Treatment-naive GT 1b-infected patients from mainland China, South Korea and Russia were assessed for SVR at follow-up week 12 (SVR12) after receiving daclatasvir (60 mg, QD) and asunaprevir (100 mg, BID) (DCV+ASV). Methods: Patients were randomized 3:1 to receive DCV+ASV (24 weeks; immediate treatment [IM]) or 12 weeks of placebo followed by DCV+ASV (24 weeks; placebo-deferred treatment [PD]). The primary endpoint was to evaluate SVR12 in the IM arm to the historical rate for peginterferon/ribavirin (70%). Secondary endpoints included overall safety and safety comparisons between the treatment arms during the first 12 weeks. Results: 207 patients were randomized to IM (n=155) or PD (n=52); Asian (86%), female (59%), IL28B CC genotype (68%) and median age 49 (range 18-73) years; cirrhosis (13%), HCV RNA ≥6x106 IU/mL (53%). SVR12 in the IM arm was 92% and broadly unaffected by most baseline factors assessed (Figure); SVR12 was higher in patients without (96%) baseline NS5A-L31M/V or Y93H polymorphisms. There were 6 virologic breakthroughs, 6 relapses and 1 detectable HCV RNA at end-of-treatment in the IM arm. Safety was mostly comparable between the two arms during the first 12 weeks. The most frequent adverse events (AEs; ≥5%) during DCV+ASV (24 weeks) treatment in both arms were aminotransferase, bilirubin and INR elevations, hypertension, fatigue and respiratory tract infections; the most frequent treatment-emergent grade 3/4 laboratory abnormalities were aminotransferase (≤4.5%) and hematologic, lipase and total bilirubin abnormalities (≤2%); one patient (IM) discontinued DCV+ASV for aminotransferase elevations, nausea and jaundice (all reversible); one patient PD) discontinued DCV+ASV for a fatal AE unrelated to treatment. Conclusions: These data demonstrate that DCV+ASV is a highly efficacious and well tolerated treatment for treatment-naive HCV GT 1b-infected patients. Those treated immediately with DCV+ASV achieved a 92% SVR12 rate which was unaffected by factors known to attenuate response to interferon.

Genetic polymorphism in pvmdr1 and pvcrt-o genes in relation to in vitro drug susceptibility of Plasmodium vivax isolates from malaria-endemic countries

Lu, F.,Lim, C.S.,Nam, D.H.,Kim, K.,Lin, K.,Kim, T.S.,Lee, H.W.,Chen, J.H.,Wang, Y.,Sattabongkot, J.,Han, E.T. Verlag für Recht und Gesellschaft ; Elsevier 2011 Acta Tropica Vol.117 No.2

Treatment failure of chloroquine for Plasmodium vivax infection has increased in endemic countries. However, the molecular mechanisms for resistance and in vitro susceptibility of P. vivax to chloroquine remain elusive. We investigated the prevalence of mutations in the pvmdr1 and pvcrt-o genes, and the copy number of the pvmdr1 gene in isolates from the Republic of Korea (ROK), Thailand, the Union of Myanmar (Myanmar), and Papua New Guinea (PNG). We also measured in vitro susceptibility of Korean isolates to antimalarial drugs. The pvmdr1 analysis showed that mutations at amino acid position Y976F of pvmdr1 were found in isolates from Thailand (17.9%), Myanmar (13.3%), and PNG (100%), but none from the ROK, and mutation at position F1076L was present in isolates from the ROK (100%), Thailand (60.7%), and Myanmar (46.7%). One copy of the pvmdr1 gene was observed in most isolates and double copy numbers of the gene were observed in two Thai isolates. In the exons of the pvcrt-o gene that were sequenced, a K10 insertion was present in isolates from Thailand (56.0%) and Myanmar (46.2%), and the wild type was found in all Korean isolates. The results suggest that gene polymorphisms and copy number variation was observed in isolates of P. vivax from Southeast Asian countries. In Korean isolates polymorphism as limited to the F1076L variant, and no isolates with high level of resistance were found by in vitro susceptibility determinations. Moreover, our results provide a baseline for future prospective drug studies in malaria-endemic areas.

Radiative decay of theψ(2S)into two pseudoscalar mesons

Bai, J. Z.,Ban, Y.,Bian, J. G.,Blum, I.,Chen, A. D.,Chen, G. P.,Chen, H. F.,Chen, H. S.,Chen, J.,Chen, J. C.,Chen, X. D.,Chen, Y.,Chen, Y. B.,Cheng, B. S.,Choi, J. B.,Cui, X. Z.,Ding, H. L.,Dong, L. Y American Physical Society 2003 Physical review. D, Particles and fields Vol.67 No.3

EXPERIMENTAL STUDY ON REGENERATING FOULED EGR COOLER BY NTPI TECHNOLOGY

Y. Y. CHEN,Y. X. CAI,X. H. LI,Y. X. SHI,Y. ZHENG 한국자동차공학회 2015 International journal of automotive technology Vol.16 No.2

In order to investigate the regeneration effect of non-thermal plasma injection (NTPI) technology on fouled exhaust gas recirculation (EGR) cooler, NTPI regeneration apparatus and EGR cooler performance test system were built up. Results showed that non-thermal plasma (NTP) could peel off the deposit layer and improve the heat exchange performance effectively. The carbon removal energy efficiency of this NTPI regeneration setup was 22.46 g/kWh and the O3 utilization ratio was 96.50%. To get a deeper understanding of the regeneration effect, thermo-gravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR) were introduced to investigate the variation of deposit layer’s physical and chemical characteristics before and after regeneration. Results showed that the content of soluble organic fraction (SOF) in deposit specimen decreased obviously, mainly because the carbonyls were effectively removed by NTP. Moreover, soot in deposit specimen was successfully activated by NTP.

Schoolchildren's antioxidation genotypes are susceptible factors for reduced lung function and airway inflammation caused by air pollution

Chen, B.Y.,Chen, C.H.,Chuang, Y.C.,Kim, H.,Honda, Y.,Chiang, H.C.,Guo, Y.L. Academic Press 2016 Environmental research Vol.149 No.-

Background: We recently reported the relationship between exposure to ambient air pollutants and changes in lung function and nasal inflammation among schoolchildren. A study was conducted to investigate whether antioxidation genotypes influence these associations. Methods: A follow-up study of 97 schoolchildren was conducted in New Taipei City, Taiwan. A structured respiratory health questionnaire was administered in September 2007, followed by monthly spirometry and measurement of nasal inflammation from October 2007 to November 2009. During the study period, complete daily monitoring data for air pollutants were obtained from the Environmental Protection Administration monitoring station and Aerosol Supersite. The genotypes of glutathione S-transferase (GST) subunits M1, T1, P1 and superoxide dismutases subunit 2 (SOD2) were characterized. Mixed-effects models were used, adjusting for known confounders. Result: GSTM1 null children had significant PM<SUB>2.5</SUB>-related increment in leukocyte (8.52%; 95% confidence interval (CI): 3.13-13.92%) and neutrophil (9.68%; 95% CI: 4.51-14.85%) in nasal lavage. Ozone levels were significantly and inversely associated with forced expiratory flow at 25% of forced vital capacity (FEF<SUB>25%</SUB>) (-0.43L/s; 95% CI: -0.58,-0.28L/s) in SOD2 Ala16 variant children. Conclusion: In this longitudinal study of schoolchildren. Our data provide evidence that antioxidation genotype modifies the airway inflammation caused by PM<SUB>2.5</SUB>. Antioxidation genotype also acts as an effect modifier, but not strong, in ozone-related small airway function response.

Fragile X-like behaviors and abnormal cortical dendritic spines in <i>Cytoplasmic FMR1-interacting protein 2</i>-mutant mice

Han, Kihoon,Chen, Hogmei,Gennarino, Vincenzo A.,Richman, Ronald,Lu, Hui-Chen,Zoghbi, Huda Y. IRL Press 2015 Human molecular genetics Vol.24 No.7

<P>Silencing of fragile X mental retardation 1 (<I>FMR1</I>) gene and loss of fragile X mental retardation protein (FMRP) cause fragile X syndrome (FXS), a genetic disorder characterized by intellectual disability and autistic behaviors. FMRP is an mRNA-binding protein regulating neuronal translation of target mRNAs. Abnormalities in actin-rich dendritic spines are major neuronal features in FXS, but the molecular mechanism and identity of FMRP targets mediating this phenotype remain largely unknown. Cytoplasmic FMR1-interacting protein 2 (Cyfip2) was identified as an interactor of FMRP, and its mRNA is a highly ranked FMRP target in mouse brain. Importantly, Cyfip2 is a component of WAVE regulatory complex, a key regulator of actin cytoskeleton, suggesting that Cyfip2 could be implicated in the dendritic spine phenotype of FXS. Here, we generated and characterized <I>Cyfip2</I>-mutant (<I>Cyfip2<SUP>+/−</SUP></I>) mice. We found that <I>Cyfip2<SUP>+/−</SUP></I> mice exhibited behavioral phenotypes similar to <I>Fmr1</I>-null (<I>Fmr1<SUP>−/y</SUP></I>) mice, an animal model of FXS. Synaptic plasticity and dendritic spines were normal in <I>Cyfip2<SUP>+/−</SUP></I> hippocampus. However, dendritic spines were altered in <I>Cyfip2<SUP>+/−</SUP></I> cortex, and the dendritic spine phenotype of <I>Fmr1<SUP>−/y</SUP></I> cortex was aggravated in <I>Fmr1<SUP>−/y</SUP></I>; <I>Cyfip2<SUP>+/−</SUP></I> double-mutant mice. In addition to the spine changes at basal state, metabotropic glutamate receptor (mGluR)-induced dendritic spine regulation was impaired in both <I>Fmr1<SUP>−/y</SUP></I> and <I>Cyfip2<SUP>+/−</SUP></I> cortical neurons. Mechanistically, mGluR activation induced mRNA translation-dependent increase of Cyfip2 in wild-type cortical neurons, but not in <I>Fmr1<SUP>−/y</SUP></I> or <I>Cyfip2<SUP>+/−</SUP></I> neurons. These results suggest that misregulation of Cyfip2 function and its mGluR-induced expression contribute to the neurobehavioral phenotypes of FXS.</P>

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.

Nonlinear dynamic analysis for a Francis hydro-turbine governing system and its control

Chen, D.,Ding, C.,Do, Y.,Ma, X.,Zhao, H.,Wang, Y. Pergamon Press [etc.] 2014 Journal of the Franklin Institute Vol.351 No.9

In this paper, we introduce a novel model of a hydro-turbine system with the effect of surge tank based on state-space equations to study the nonlinear dynamical behaviors of the hydro-turbine system. The critical points of Hopf bifurcation and the relationship of the stability satisfying with the adjustment coefficients are obtained from direct algebraic criterion. Furthermore, the bifurcation diagrams and Lyapunov exponents are presented and analyzed. The dynamical behaviors of the points with representative characteristics are identified and studied in detail. Both theoretical analysis and numerical simulations show that chaotic oscillations, which cannot stabilize the system, may occur with the changes of adjustment coefficients. To control the undesirable chaotic behaviors in this system, fuzzy sliding mode governor based on the sliding mode control (SMC) and the fuzzy logic are designed, and considering the bounded disturbance. Finally, series of numerical simulations are presented to verify the effectiveness of the proposed governor, which prove that the hydro-turbine governing system can maintain a better operation station under the designed governor.