• Title/Summary/Keyword: growth state

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Growth Behavior of Intermetallic Compounds in Sn-Ag-Bi/Cu Solder Joints during Aging (Sn-Ag-Bi/Cu 솔더 조인트의 aging시 금속간화합물 성장 거동)

  • Han Sang Uk;Park Chang Yong;Heo Ju Yeol
    • Proceedings of the International Microelectronics And Packaging Society Conference
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    • 2003.11a
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    • pp.133-137
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    • 2003
  • The effect of Bi additions to the eutectic Sn-3.5Ag solder alloy on the growth kinetics of the intermetallic compound (IMC) layers during solid-state aging of Sn-Ag-Bi/Cu solder joints has been Investigated. The Bi additions enhanced the growth rate of the total IMC layer comprising of $Cu_6Sn_5$ and $Cu_3Sn$ sublayers. This enhanced IMC growth rate was primarily due to the rapid increase In the growth rate of $Cu_6Sn_5$ sublayer. The growth rate of $Cu_3Sn$ sublayers was little influenced and appeared to be retarded by the Bi additions. The observed growth behavior of $Cu_6Sn_5$ and $Cu_3Sn$ sublayers could be understood if the interfacial reaction barrier at the $Cu_6Sn_5/solder$ interface were reduced by the segregation of Bi at the interface.

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Crack growth life model for fatigue susceptible structural components in aging aircraft

  • Chou, Karen C.;Cox, Glenn C.;Lockwood, Allison M.
    • Structural Engineering and Mechanics
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    • v.17 no.1
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    • pp.29-50
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    • 2004
  • A total life model was developed to assess the service life of aging aircraft. The primary focus of this paper is the development of crack growth life projection using the response surface method. Crack growth life projection is a necessary component of the total life model. The study showed that the number of load cycles N needed for a crack to propagate to a specified size can be linearly related to the geometric parameter, material, and stress level of the component considered when all the variables are transformed to logarithmic values. By the Central Limit theorem, the ln N was approximated by Gaussian distribution. This Gaussian model compared well with the histograms of the number of load cycles generated from simulated crack growth curves. The outcome of this study will aid engineers in designing their crack growth experiments to develop the stochastic crack growth models for service life assessments.

Vibrio alginolyticus MviN is a LuxO-regulated Protein and Affects Cytotoxicity Towards Epithelioma Papulosum Cyprini (EPC) Cells

  • Cao, Xiaodan;Wang, Qiyao;Liu, Qin;Liu, Huan;He, Honghong;Zhang, Yuanxing
    • Journal of Microbiology and Biotechnology
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    • v.20 no.2
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    • pp.271-280
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    • 2010
  • Vibrio alginolyticus, a Gram-negative marine bacterium, is one of the causative agents of fish vibriosis. Its virulence factors and pathogenesis mechanism are barely known, except for some extracellular products (ECPs) that are known to be regulated by quorum sensing system. Therefore, the present study used a microarray to analyze the transcription profiles of the wild-type V. alginolyticus and a deletion mutant of luxO, the pivotal regulator in Vibrio quorum sensing systems, which resulted in the identification of a putative virulence factor, MviN. Quantitative real-time reverse transcription PCR confirmed that the transcription of mviN was upregulated in the luxO mutant when compared with wild-type, and down regulated in a luxO-con complemented strain. Furthermore, Western blotting indicated that MviN was greatly induced during the late-exponential and stationary phases of growth, indicating that the expression of MviN was cell-density dependent and quorum sensing regulated in V. alginolyticus. Meanwhile, the mviN null mutant displayed a much slower growth rate than the wild type, signifying the essential role of MviN in V. alginolyticus. Western blotting also revealed that MviN was present as an extracellular protein in V. alginolyticus. When epithelioma papulosum cyprini (EPC) cells were treated with the ECPs of the mviN mutant, no cytotoxicity was observed, whereas EPC cells treated with the wild type exhibited pathological changes, which increased with the ECPs concentration and treatment time. Therefore, the results demonstrated that MviN is a LuxO-regulated ECPs component and involved in the pathogenicity of V. alginolyticus.

MSP58 Knockdown Inhibits the Proliferation of Esophageal Squamous Cell Carcinoma in Vitro and in Vivo

  • Xu, Chun-Sheng;Zheng, Jian-Yong;Zhang, Hai-Long;Zhao, Hua-Dong;Zhang, Jing;Wu, Guo-Qiang;Wu, Lin;Wang, Qing;Wang, Wei-Zhong;Zhang, Jian
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.7
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    • pp.3233-3238
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    • 2012
  • Esophageal carcinoma (EC) is one of the most aggressive cancers with a poor prognosis. Understanding the molecular mechanisms underlying esophageal cancer progression is a high priority for improved EC diagnosis and prognosis. Recently, MSP58 was shown to behave as an oncogene in colorectal carcinomas and gliomas. However, little is known about its function in esophageal carcinomas. We therefore examined the effects of MSP58 knockdown on the growth of esophageal squamous cell carcinoma (ESCC) cells in vitro and in vivo in order to gain a better understanding of its potential as a tumor therapeutic target. We employed lentiviral-mediated small hairpin RNA (shRNA) to knock down the expression of MSP58 in the ESCC cell lines Eca-109 and EC9706 and demonstrated inhibition of ESCC cell proliferation and colony formation in vitro. Furthermore, flow cytometry and western blot analyses revealed that MSP58 depletion induced cell cycle arrest by regulating the expression of P21, CDK4 and cyclin D1. Notably, the downregulation of MSP58 significantly inhibited the growth of ESCC xenografts in nude mice. Our results suggest that MSP58 may play an important role in ESCC progression.

Resistance Function of Rice Lipid Transfer Protein LTP110

  • Ge, Xiaochun;Chen, Jichao;Li, Ning;Lin, Yi;Sun, Chongrong;Cao, Kaiming
    • BMB Reports
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    • v.36 no.6
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    • pp.603-607
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    • 2003
  • Abstract Plant lipid transfer proteins (LTPs) are a class of proteins whose functions are still unknown. Some are proposed to have antimicrobial activities. To understand whether LTP110, a rice LTP that we previously identified from rice leaves, plays a role in the protection function against some serious rice pathogens, we investigated the antifungal and antibacterial properties of LTP110. A cDNA sequence, encoding the mature peptide of LTP110, was cloned into the Impact-CN prokaryotic expression system. The purified protein was used for an in vitro inhibition test against rice pathogens, Pyricularia oryzae and Xanthomonas oryzae. The results showed that LTP110 inhibited the germination of Pyricularia oryzae spores, and its inhibitory activity decreased in the presence of a divalent cation. This suggests that the antifungal activity is affected by ions in the media; LTP110 only slightly inhibited the growth of Xanthomonas oryzae. However, the addition of LTP110 to cultured Chinese hamster ovarian cells did not retard growth, suggesting that the toxicity of LTP110 is only restricted to some cell types. Its antimicrobial activity is potentially due to interactions between LTP and microbe-specific structures.

State-Owned enterprises as ICSID claimants and establishment of jurisdiction: The Decision on Jurisdiction in BUCG v. Yemen (공기업의 ICSID 중재 신청과 관할권 성립: BUCG v. Yemen 사건을 중심으로)

  • Chang, Sok Young
    • Journal of Arbitration Studies
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    • v.28 no.1
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    • pp.27-42
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    • 2018
  • Due to the increasing number of foreign investments made by state-owned enterprises, there has been a growth in the number of investment arbitration claims submitted by them. However, international investment treaties including the ICSID Convention are intended to apply to investor-state disputes and according to Article 25 of the ICSID Convention, the claimant has to be "a national of another Contracting State." This raises the question of whether state-owned companies can be considered as "nationals of another Contracting State" or private investors. This issue has been discussed in the ICSID Decision on Jurisdiction in BUCG v. Yemen which has been released in 2017. Since there would be more claims related to the standing of state-owned enterprises as claimants, it is required to understand whether state-owned enterprises could be permitted access to the ICSID under the ICSID Convention Article 25. Moreover, the ICSID cases addressing the jurisdictional issues including BUCG v. Yemen has to be closely analyzed. In particular, as the Broches test was applied in order to decide the standing of state-owned companies, it is necessary to examine how the Broches criteria has been interpreted and adopted in the ICSID cases.

Correlation Between Transient Regime and Steady-State Regime on Creep Crack Growth Behavior of Grade 91 Steel (Grade 91 강의 크리프 균열성장 거동에 대한 천이영역과 정상상태영역의 상관 관계)

  • Park, Jae-Young;Kim, Woo-Gon;Ekaputra, I.M.W.;Kim, Seon-Jin;Kim, Eung-Seon
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.39 no.12
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    • pp.1257-1263
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    • 2015
  • A correlation between the transient regime and steady state regime on the creep crack growth (CCG) for Grade 91 steel, which is used as the structural material for the Gen-IV reactor systems, was investigated. A series of CCG tests were performed using 1/2" CT specimens under a constant applied load and at a constant temperature of $600^{\circ}C$. The CCG rates for the transient and steady state regimes were obtained in terms of $C^*$ parameter. The transient CCG rate had a close correlation with the steady-state CCG rate, as the slope of the transient CCG data was very similar to that of the steady state data. The transient rate was slower by 5.6 times as compared to the steady state rate. It can be inferred that the steady state CCG rate, which is required for long-time tests, can be predicted from the transient CCG rate obtained from short-time tests.

PKHD1 Gene Silencing May Cause Cell Abnormal Proliferation through Modulation of Intracellular Calcium in Autosomal Recessive Polycystic Kidney Disease

  • Yang, Ji-Yun;Zhang, Sizhong;Zhou, Qin;Guo, Hong;Zhang, Ke;Zheng, Rong;Xiao, Cuiying
    • BMB Reports
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    • v.40 no.4
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    • pp.467-474
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    • 2007
  • Autosomal recessive polycystic kidney disease (ARPKD) is one of the important genetic disorders in pediatric practice. Mutation of the polycystic kidney and hepatic disease gene 1 (PKHD1) was identified as the cause of ARPKD. The gene encodes a 67-exon transcript for a large protein of 4074 amino acids termed fibrocystin, but its function remains unknown. The neoplastic-like in cystic epithelial proliferation and the epidermal growth factor/epidermal growth factor receptor (EGF/EGFR) axis overactivity are known as the most important characteristics of ARPKD. Since the misregulation of $Ca^{2+}$ signaling may lead to aberrant structure and function of the collecting ducts in kidney of rat with ARPKD, present study aimed to investigate the further mechanisms of abnormal proliferation of cystic cells by inhibition of PKHD1 expression. For this, a stable PKHD1-silenced HEK-293T cell line was established. Then cell proliferation rates, intracellular $Ca^{2+}$ concentration and extracellular signal-regulated kinase 1/2 (ERK1/2) activity were assessed after treatment with EGF, a calcium channel blocker and agonist, verapamil and Bay K8644. It was found that PKHD1-silenced HEK-293T cell lines were hyperproliferative to EGF stimulation. Also PKHD1-silencing lowered the intracellular $Ca^{2+}$ and caused EGF-induced ERK1/2 overactivation in the cells. An increase of intracellular $Ca^{2+}$ in PKHD1-silenced cells repressed the EGF-dependent ERK1/2 activation and the hyperproliferative response to EGF stimulation. Thus, inhibition of PKHD1 can cause EGF-induced excessive proliferation through decreasing intracellular $Ca^{2+}$ resulting in EGF-induced ERK1/2 activation. Our results suggest that the loss of fibrocystin may lead to abnormal proliferation in kidney epithelial cells and cyst formation in ARPKD by modulation of intracellular $Ca^{2+}$.

Effects of Bedding Material Composition in Deep Litter Systems on Bedding Characteristics and Growth Performance of Limousin Calves

  • Meng, J.;Shi, F.H.;Meng, Qingxiang;Ren, L.P.;Zhou, Z.M.;Wu, H.;Zhao, L.P.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.1
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    • pp.143-150
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    • 2015
  • The objective of this study was to evaluate the effects of different litter mixture compositions on bedding system temperature, pH and volatile fatty acid and ammonia-N ($NH_3$-N) content, and the serum physico-chemical parameters and growth indices of calves. Thirty-two Limousin calves ($280{\pm}20kg$) were randomly assigned to four groups (n = 8 for each group) according to the bedding system used: i) control with soil only (CTR); ii) mixture with 50% paddy hulls (PH), 30% saw dusts (SD), 10% peat moss (PM) and 10% corn cobs (CC) (TRT1); iii) mixture with 15% PH, 15% SD, 10% PM, 40% CC, and 20% corn stover (CS) (TRT2); iv) mixture with 30% PH, 10% PM, 40% CC, and 20% CS (TRT3). The litter material combinations of different treatments were based on the cost of bedding system materials in China. The cost of four treatments from low to high: Control$NH_3$-N level (271.83 to 894.72 mg/kg) was lowest for TRT1 (p<0.0001) and highest for TRT2 (p<0.0001). The acetate, propionate and butyrate levels were highest for the control group (p<0.0001). In all the groups, the pH value (6.90 to 9.09) increased at the beginning and later remained stable at below 9.09. The temperature of deep litter increased at the first week and reached the maximum ($42.1^{\circ}C$) on day 38. 3,5,3'-Triiodothyronine ($T_3$) levels in the TRT1 group animals (p<0.0001) were lower than those in the control and TRT2 animals. 3,5,3',5'-Tetraiodothyronine ($T_4$) in the TRT1 group (p = 0.006) was lower than that in the other treatment groups. Cortisol (COR) in the control and TRT1 group was lower (p<0.0001) than that in the TRT2 and TRT3 groups. Corticosterone (CORt) in the control group was higher (p<0.0001) than that in the treatment groups. The findings indicate that the deep litter bedding systems provided better conditions for animal health and growth performance compared with the control system. Furthermore, the litter composition of TRT1 was found to be optimal among the three treatment groups.

Forsythia suspensa Extract Has the Potential to Substitute Antibiotic in Broiler Chicken

  • Han, X.;Piao, X.S.;Zhang, H.Y.;Li, P.F.;Yi, J.Q.;Zhang, Q.;Li, P.
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.4
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    • pp.569-576
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    • 2012
  • Two experiments were conducted to investigate the potential for Forsythia suspensa extract (FSE) to substitute for antibiotic in broiler chicken. First, a well-diffusion assay procedure and a 2-fold dilution method were used to determine the bacteriostatic activity of FSE on Escherichia coli K88, staphylococcus aureus, and salmonella was assayed. An inhibitory effect of FSE was observed on the growth of these bacteria. This effect seems to be dose depended, which disappeared after 25.00, 12.50, 1.56 mg/ml. Second, a 42-d trial with 252 broiler chickens (d 1, $38.7{\pm}1.1$ g BW) was conducted to evaluate the effect of dietary supplementation of FSE in broiler chicken. The feeding program consisted of a starter diet from d 1 to 21 and a finisher diet from d 22 to 42. Dietary treatments included were: i) NC: negative control fed a corn-soybean meal based diet; ii) PC: positive control group fed based diet with chlortetracycline; and iii) FC: a test group fed with 100 mg FSE/kg diet. In this study growth performance did not differ among treatments during the starter period. However, dietary supplemental chlortetracycline and FSE increased (p<0.05) average daily gain (ADG), average daily feed intake (ADFI) compared with NC during the finisher and overall phase. Apparent digestibility of calcium on d 21, digestibility of energy and calcium on d 42 of FC was greater (p<0.05) than NC. Moreover, cecal Escherichia coli counts for birds from FC were lower (p<0.05) than NC. Dietary FSE supplementation also improved (p<0.05) villus height and villus height to crypt depth ratios in both duodenum and ileum and decreased (p<0.05) crypt depth in the duodenum. Duodenum villus height and villus height to crypt depth ratio in both duodenum and ileum from the FC group were also greater (p<0.05). Serum growth hormone and IGF-1 were not influenced by different treatments. Apparently, FSE has the potential to substitute for antibiotic in broiler chicken.