• Title/Summary/Keyword: model factor

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Influence of ventilation rate on the aerodynamic interference between two extra-large indirect dry cooling towers by CFD

  • Ke, S.T.;Liang, J.;Zhao, L.;Ge, Y.J.
    • Wind and Structures
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    • v.20 no.3
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    • pp.449-468
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    • 2015
  • Current wind-resistance designs of large-scale indirect dry cooling towers (IDCTs) exclude an important factor: the influence of the ventilation rate for radiator shutter on wind loads on the outer surfaces of the tower shell. More seemingly overlooked aspects are the effects of various ventilation rates on the wind pressure distribution on the tower surfaces of two IDCTs, and the feature of the flow field around them. In order to investigate the effects of the radiator shutter ventilation rates on the aerodynamic interference between IDCTs, this paper established the numerical wind tunnel model based on the Computational Fluid Dynamic (CFD) technology, and analyzed the influences of various radiator shutter ventilation rates on the aerodynamic loads acting upon a single and two extra-large IDCTs during building, installation, and operation stages. Through the comparison with the results of physical wind tunnel test and different design codes, the results indicated that: the influence of the ventilation rate on the flow field and shape coefficients on the outer surface of a single IDCT is weak, and the curve of mean shape coefficients is close to the reference curve provided by the current design code. In a two-tower combination, the ventilation rate significantly affects the downwind surface of the front tower and the upwind surface of the back tower, and the larger positive pressure shifts down along the upwind surface of the back tower as the ventilation rate increases. The ventilation rate significantly influences the drag force coefficient of the back tower in a two-tower combination, the drag force coefficient increases with the ventilation rate and reaches the maximum in a building status of full ventilation, and the maximum drag coefficient is 11% greater than that with complete closure.

Advanced discretization of rock slope using block theory within the framework of discontinuous deformation analysis

  • Wang, Shuhong;Huang, Runqiu;Ni, Pengpeng;Jeon, Seokwon
    • Geomechanics and Engineering
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    • v.12 no.4
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    • pp.723-738
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    • 2017
  • Rock is a heterogeneous material, which introduces complexity in the analysis of rock slopes, since both the existing discontinuities within the rock mass and the intact rock contribute to the degradation of strength. Rock failure is often catastrophic due to the brittle nature of the material, involving the sliding along structural planes and the fracturing of rock bridge. This paper proposes an advanced discretization method of rock mass based on block theory. An in-house software, GeoSMA-3D, has been developed to generate the discrete fracture network (DFN) model, considering both measured and artificial joints. Measured joints are obtained from the photogrammetry analysis on the excavation face. Statistical tools then facilitate to derive artificial joints within the rock mass. Key blocks are searched to provide guidance on potential reinforcement measures. The discretized blocky system is subsequently implemented into a discontinuous deformation analysis (DDA) code. Strength reduction technique is employed to analyze the stability of the slope, where the factor of safety can be obtained once excessive deformation of slope profile is observed. The combined analysis approach also provides the failure mode, which can be used to guide the choice of strengthening strategy if needed. Finally, an illustrated example is presented for the analysis of a rock slope of 20 m height inclined at $60^{\circ}$ using combined GeoSMA-3D and DDA calculation.

Identification of genes related to intramuscular fat content of pigs using genome-wide association study

  • Won, Sohyoung;Jung, Jaehoon;Park, Eungwoo;Kim, Heebal
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.2
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    • pp.157-162
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    • 2018
  • Objective: The aim of this study is to identify single nucleotide polymorphisms (SNPs) and genes related to pig IMF and estimate the heritability of intramuscular fat content (IMF). Methods: Genome-wide association study (GWAS) on 704 inbred Berkshires was performed for IMF. To consider the inbreeding among samples, associations of the SNPs with IMF were tested as random effects in a mixed linear model using the genetic relationship matrix by GEMMA. Significant genes were compared with reported pig IMF quantitative trait loci (QTL) regions and functional classification of the identified genes were also performed. Heritability of IMF was estimated by GCTA tool. Results: Total 365 SNPs were found to be significant from a cutoff of p-value <0.01 and the 365 significant SNPs were annotated across 120 genes. Twenty five genes were on pig IMF QTL regions. Bone morphogenetic protein-binding endothelial cell precursor-derived regulator, forkhead box protein O1, ectodysplasin A receptor, ring finger protein 149, cluster of differentiation, tyrosine-protein phosphatase non-receptor type 1, SRY (sex determining region Y)-box 9 (SOX9), MYC proto-oncogene, and macrophage migration inhibitory factor were related to mitogen-activated protein kinase pathway, which regulates the differentiation to adipocytes. These genes and the genes mapped on QTLs could be the candidate genes affecting IMF. Heritability of IMF was estimated as 0.52, which was relatively high, suggesting that a considerable portion of the total variance of IMF is explained by the SNP information. Conclusion: Our results can contribute to breeding pigs with better IMF and therefore, producing pork with better sensory qualities.

Predicting Factors of Post-Stroke Depression (뇌졸중 후 우울에 영향을 미치는 요인)

  • Kim, In Ja;Suh, Moon Ja;Kim, Kum Soon;Cho, Nam Ok;Choi, Hee Jung
    • Korean Journal of Adult Nursing
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    • v.12 no.1
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    • pp.147-162
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    • 2000
  • Predicting factors of post-stroke depression were investigated. The subjects were 254 stroke patients who had been discharged and visited regularly the outpatient clinic for follow up care. The influencing factors were classified into five categories : demographic, disease-related, current state, social support, and illness intrusiveness. Sex, age, job, and educational level were defined as the demographic factor. The disease-related factors included stroke type, illness duration, attack frequency, and NIH score. ADL, cognitive function, and social activity were considered as the current state factors. The social support was measured as the perceived amount of social support. Illness intrusiveness means the perceived illness induced life style disruptions. Demographic, disease-related, current state, and social support were hypothesized to directly and indirectly affect post-stroke depression through illness intrusiveness. The illness intrusiveness was hypothesized to directly affect post-stroke depression. The hierarchial multiple regression was used to identify significant factors. The result showed that this model explained 43.3% of variance of post-stroke depression. And the prevalence of post-stroke depression was 38.8%. Among the demographic factors, job was identified as a main contributor to indirectly increase the post-stroke depression. Among the disease-related factors, stroke type, attack frequency, and NIH score were found to indirectly affect the post-stroke depression. Among the current state factors, ADL and social activity indirectly affected the post-stroke depression through illness intrusiveness. Social support and illness intrusiveness were identified to directly affect the post-stroke depression. This study has proved the factors likely to be implicated in the development of post-stroke depression. Based upon these results, it is recommended that the nurses who take care of post-stroke patients consider the risk factors such as social support, illness intrusiveness et al. Also programs which decrease the illness intrusiveness and increase the social support to reduce post-stoke depression recommended to be developed.

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Prediction of Time to Recurrence and Influencing Factors for Gastric Cancer in Iran

  • Roshanaei, Ghodratollah;Ghannad, Masoud Sabouri;Safari, Maliheh;Sadighi, Sanambar
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.6
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    • pp.2639-2642
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    • 2012
  • Background: The patterns of gastric cancer recurrence vary across societies. We designed the current study in an attempt to evaluate and reveal the outbreak of the recurrence patterns of gastric cancer and also prediction of time to recurrence and its effected factors in Iran. Materials and Methods: This research was performed from March 2003 to February 2007. Demographic characteristics, clinical and pathological diagnosis and classification including pathologic stage, tumor grade, tumor site and tumor size in of patients with GC recurrent were collected from patients' data files. To evaluate of factors affected on the relapse of the GC patients, gender, age at diagnosis, treatment type and Hgb were included in the research. Data were analyzed using Kaplan-Meier and logistic regression models. Results: After treatment, 82 patients suffered recurrence, 42, 33 and 17 by the ends of first, second and third years. The mean ( SD) and median ( IQR) time to recurrence in patients with GC were 25.5 (20.6-30.1) and 21.5 (15.6-27.1) months, respectively. The results of multivariate analysis logistic regression showed that only pathologic stage, tumor grade and tumor site significantly affected the recurrence. Conclusions: We found that pathologic stage, tumor grade and tumor site significantly affect on the recurrence of GC which has a high positive prognostic value and might be functional for better follow-up and selecting the patients at risk. We also showed time to recurrence to be an important factor for follow-up of patients.

Socio Demographic and Reproductive Risk Factors for Cervical Cancer - a Large Prospective Cohort Study from Rural India

  • Thulaseedharan, Jissa V.;Malila, Nea;Hakama, Matti;Esmy, Pulikottil O.;Cheriyan, Mary;Swaminathan, Rajaraman;Muwonge, Richard;Sankaranarayanan, Rengaswami
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.6
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    • pp.2991-2995
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    • 2012
  • Background: India shows some of the highest rates of cervical cancer worldwide, and more than 70% of the population is living in rural villages. Prospective cohort studies to determine the risk factors for cervical cancer are very rare from low and medium resource countries. The aim of this study was to quantify the effect of risk factors related to cervical cancer in a rural setting in South India. Material and methods: Sociodemographic and reproductive potential risk factors for cervical cancer were studied using the data from a cohort of 30,958 women who constituted the unscreened control group in a randomised screening trial in Dindigul district, Tamilnadu, India. The analysis was accomplished with the Cox proportional hazard regression model. Results: Women of increasing age (HR=2.4; 95% CI: 1.6, 3.8 in 50-59 vs 30-39), having many pregnancies (HR=7.1; 1.0, 52 in 4+ vs 0) and no education (HR=0.6; 0.2, 0.7 in high vs none) were found to be at significantly increased risk of cervical cancer. Conclusion: This cohort study gives very strong evidence to say that education is the fundamental factor among the sociodemographic and reproductive determinants of cervical cancer in low resource settings. Public awareness through education and improvements in living standards can play an important role in reducing the high incidence of cervical cancer in India. These findings further stress the importance of formulating public health policies aimed at increasing awareness and implementation of cervical cancer screening programmes.

Elevated PIVKA-II is Associated with Early Recurrence and Poor Prognosis in BCLC 0-A Hepatocellular Carcinomas

  • Wang, Bei-Li;Tan, Qi-Wen;Gao, Xing-Hui;Wu, Jiong;Guo, Wei
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.16
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    • pp.6673-6678
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    • 2014
  • Background: To investigate the prognostic value of serum PIVKA-II (prothrombin induced by the absence of vitamin K or antagonist-II) in BCLC (Barcelona Clinic Liver Cancer) 0-A hepatocellular carcinoma (HCC) patients after curative resection. Materials and Methods: Preoperative sera were collected from 140 patients with BCLC 0-A HCCs undergoing curative resection during 2011-2012 in Zhongshan Hospital. Follow-up ended on November 2013. ELISA was used to detect the serum concentrations of preoperative PIVKA-II. The prognostic value of PIVKA-II and other clinicopathological factors was analyzed by the Kaplan-Meier method and the multivariate Cox proportional hazards model. Results: During follow-up, 39 of 140 patients suffered recurrence and the 1-year recurrence rate was 27.9%. The high-PIVKA-II expression group had lower 1-year time to progression (TTP) compared with the low-expression group (54.8% vs 20.2%, p<0.001). Patients with high preoperative PIVKA-II expression showed a relatively higher risk of developing postoperative recurrence than those with low expression in the low-recurrence-risk subgroups, including ${\alpha}$-fetoprotein ${\leq}400ng/mL$ (45.4% vs 16.7%; p=0.006), tumor size ${\leq}5cm$ (54.2% vs 18.1%; p<0.001), single tumor (56.0% vs 19.1%; p<0.001), absence of satellite lesions (53.3% vs 19.8%; p=0.001), absence of vascular invasion (52.6% vs 14.9%; p=0.002), and Edmondson stage I/II (60.9% vs 20.3%; p<0.001). PIVKA-II was the strongest independent prognostic factor for TTP (hazard ratio, 2.877; 95% CI 1.524-5.429; p=0.001). Conclusions: Elevated PIVKA-II is associated with early recurrence of BCLC 0-A HCC after curative resection and can be considered a novel prognostic predictor.

Lack of Association of the Cyclooxygenase-2 Gene 8473T>C Polymorphism with Breast Cancer Risk: a Meta-analysis

  • Yang, Xi;Zhao, Fen;Li, Yue-Hua;Huang, Min;Huang, Ying;Yi, Cheng
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.22
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    • pp.9693-9698
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    • 2014
  • Background: Associations between the 8473T>C polymorphism (rs5275) in the cyclooxygenase-2 (COX-2) gene and breast cancer (BC) risk are still inconclusive and ambiguous. The aim of this meta-analysis was to comprehensively estimate the genetic risk of 8473T>C polymorphism in the COX-2 gene for BC. Materials and Methods: We searched PubMed, Web of Science, Medline, Chinese biomedical (CBM), Weipu, China national knowledge infrastructure (CNKI), and Wanfang databases, covering all publications (last search was updated on Aug 17, 2014). Statistical analyses were performed using Revman 5.3 and STATA 10.0 software. Results: A total of 6,720 cases and 9,794 controls in 12 studies were included in this study. The results indicated no significant associations between the 8473T>C polymorphism of the COX-2 gene and BC risk for the CC+TC vs TT model (pooled odds ratio (OR)=0.97, 95% confidence interval (CI)=0.90-1.03, and p=0.29). On subgroup analysis, we also found that subdivision on ethnicity among Caucasians, Asians and others also revealed no relationship with BC susceptibility. With the study design (CC+TC vs TT), no significant associations were found in either population-based case-control studies (PCC), or hospital-based case-control studies (HCC). Conclusions: This present meta-analysis suggests that the 8473T>C polymorphism in the COX-2 gene is not a conspicuous low-penetrant risk factor for developing BC.

Evaluation of Physical Properties as Magnesium Stearate Blendedin Hydrophilic Matrix Tablets

  • Choi, Du-Hyung;Jung, Youn-Jung;Wang, Hun-Sik;Yoon, Jeong-Hyun;Jeong, Seong-Hoon
    • Journal of Pharmaceutical Investigation
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    • v.41 no.2
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    • pp.83-90
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    • 2011
  • Main objectives of this study were to investigate the effects of a lubricant, magnesium stearate, as blended in a hydrophilic matrix tablet and to identify significant factors using a tablet ejection force and a swelling property. The characteristics of tablet ejection were evaluated with three different compression forces (30, 40, and 60 MPa) and two controlled factors, amount of magnesium stearate and its mixing time. A hydrophilic model drug (terazosin HCl dihydrate) was regarded as a default factor. Tablet swelling was also evaluated. The optimal amount of PEG compared to PEO was set to be 88.50% w/w. As the amount of magnesium stearate was varied from 0.79% to 2.20% w/w, the amount of PEO and PEG was adjusted to meet the tablet's total weight while maintaining the ratio between the two excipients constant. As the mixing time of magnesium stearate was increased, the tablet ejection force and the swelling property were decreased. As the amount of magnesium stearate was increased, the tablet ejection force and the swelling property were decreased since the increased mixing time and the amount of magnesium stearate induced hydrophobic properties of the matrix tablet more effectively. The ejection force of the tablet increased as a result of increase in the compression force, which means that the breaking of tablet/die-wall adhesion energy was also increased when the compression energy was increased. The results gavea valuable guide how to choose suitable amount of the lubricant with processing conditions for the development of hydrophilic matrix formulations.

A Study for Characteristics of PM10 in the Subway Passenger Cabins (지하철 전동차 객실에서의 PM10 오염특성 파악에 관한 연구)

  • Oh, Mi-Seok;Park, Duck-Shin;Park, Eun-Young
    • Journal of Korean Society for Atmospheric Environment
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    • v.27 no.5
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    • pp.523-533
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    • 2011
  • This study had the aim of characteristics of $PM_{10}$ in subway cabins. $PM_{10}$ was measured by times of day (rush and non rush hours) and seasons with real time $PM_{10}$ sampler on the subway cabins of line 7. Filter samples were collected for evaluation of their elemental composition as well as identification of major sources of $PM_{10}$ using a receptor model, PMF. $PM_{10}$ concentration were the highest in the winter season both in the rush and non rush hours at 152.8 ${\mu}g/m^3$, 90.2 ${\mu}g/m^3$ respectively. The $PM_{10}$ concentrations in rush hour were 30% higher compared to non rush hours. Based on the chemical information, the composition rare of inorganic elements was 52.5%, anions were 10.2% and others were 37.3%. Fe was the most abundant element and significantly correlated (p.0.01) with Mn (r=0.97), Ti (r=0.91), Cr (r=0.88), Ni (r=0.89) and Cu (r=0.88). Characterized $PM_{10}$ sources by PMF in the cabin were soil and road dust related sources (27.2%), railroad related sources (47.5%), secondary nitrate sources (16.2%) and a Cl-factor mixed with a secondary sulfate source (9.1%).