Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 16 )

2018 ( 19 )

2017 ( 15 )

2016 ( 24 )

Custom range...

Search Results: 1 - 10 of 6097 matches for " Ada Suk Fung Ng "
All listed articles are free for downloading (OA Articles)
Page 1 /6097
Display every page Item
Productive efficiencies and scale efficiencies of Chinese logistics companies

DENG Xue-ping,WANG Xu,Ada Suk Fung Ng,
,王旭,Ada Suk Fung Ng

系统工程理论与实践 , 2009,
Abstract: 首先利用DEA CCR/BCC模型对我国在沪深港证券市场上市的55家物流企业的生产效率和规模效率进行实证比较分析,然后通过相关性分析及多项回归分析研究了规模效率及固定资产规模与生产效率的关系.结果表明:1)大型物流企业相对中小型物流企业而言并不具备显著的效率优势.2)我国物流企业不存在显著的规模效率差异,不应盲目追求资产规模的扩张和重组.3)我国物流企业的纯技术效率大于规模效率对生产效率的影响,物流企业的技术改进比规模扩张更具重要性.4)物流企业生产成本是影响企业生产效率的主要因素,而资产规模和职工工资对生产效率没有显著影响.
Development analysis of Chinese logistics companies focusing on productive efficiency

DENG Xue-ping,WANG Xu,Ada Suk Fung Ng,
,王旭,Ada Suk Fung Ng

系统工程理论与实践 , 2009,
Abstract: 为分析我国物流企业生产效率的发展状况,利用DEA CCR模型和Window Analysis技术对我国18家物流企业在2001-2006年间的生产效率进行发展分析.通过分析发现:1)我国物流市场缺乏有效的市场淘汰机制,物流企业生产效率的个体差异显著;2)我国港口经营类企业的平均生产效率高于运输仓储类企业的平均生产效率;3)我国物流企业整体生产效率水平较低,但在所研究的时间内呈稳定且上升的发展状态.
CD44+ Cancer Stem-Like Cells in EBV-Associated Nasopharyngeal Carcinoma
Samantha Wei-Man Lun, Siu Tim Cheung, Phyllis Fung Yi Cheung, Ka-Fai To, John Kong-Sang Woo, Kwong-Wai Choy, Chit Chow, Chartia Ching-Mei Cheung, Grace Tin-Yun Chung, Alice Suk-Hang Cheng, Chun-Wai Ko, Sai-Wah Tsao, Pierre Busson, Margaret Heung-Ling Ng, Kwok-Wai Lo
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0052426
Abstract: Nasopharyngeal carcinoma (NPC) is a unique EBV-associated epithelial malignancy, showing highly invasive and metastatic phenotype. Despite increasing evidence demonstrating the critical role of cancer stem-like cells (CSCs) in the maintenance and progression of tumors in a variety of malignancies, the existence and properties of CSC in EBV-associated NPC are largely unknown. Our study aims to elucidate the presence and role of CSCs in the pathogenesis of this malignant disease. Sphere-forming cells were isolated from an EBV-positive NPC cell line C666-1 and its tumor-initiating properties were confirmed by in vitro and in vivo assays. In these spheroids, up-regulation of multiple stem cell markers were found. By flow cytometry, we demonstrated that both CD44 and SOX2 were overexpressed in a majority of sphere-forming C666-1 cells. The CD44+SOX2+ cells was detected in a minor population in EBV-positive xenografts and primary tumors and considered as potential CSC in NPC. Notably, the isolated CD44+ NPC cells were resistant to chemotherapeutic agents and with higher spheroid formation efficiency, showing CSC properties. On the other hand, microarray analysis has revealed a number of differentially expressed genes involved in transcription regulation (e.g. FOXN4, GLI1), immune response (CCR7, IL8) and transmembrane transport (e.g. ABCC3, ABCC11) in the spheroids. Among these genes, increased expression of CCR7 in CD44+ CSCs was confirmed in NPC xenografts and primary tumors. Importantly, blocking of CCR7 abolished the sphere-forming ability of C666-1 in vitro. Expression of CCR7 was associated with recurrent disease and distant metastasis. The current study defined the specific properties of a CSC subpopulation in EBV-associated NPC. Our findings provided new insights into developing effective therapies targeting on CSCs, thereby potentiating treatment efficacy for NPC patients.
On sparse Fisher discriminant method for microarray data analysis
Eric S. Fung,Michael K. Ng
Bioinformation , 2007,
Abstract: One of the applications of the discriminant analysis on microarray data is to classify patient and normal samples based on gene expression values. The analysis is especially important in medical trials and diagnosis of cancer subtypes. The main contribution of this paper is to propose a simple Fisher-type discriminant method on gene selection in microarray data. In the new algorithm, we calculate a weight for each gene and use the weight values as an indicator to identify the subsets of relevant genes that categorize patient and normal samples. A l2 - l1 norm minimization method is implemented to the discriminant process to automatically compute the weights of all genes in the samples. The experiments on two microarray data sets have shown that the new algorithm can generate classification results as good as other classification methods, and effectively determine relevant genes for classification purpose. In this study, we demonstrate the gene selection’s ability and the computational effectiveness of the proposed algorithm. Experimental results are given to illustrate the usefulness of the proposed model.
Work-Family Enrichment: It’s Mediating Role in the Relationships between Dispositional Factors and Job Satisfaction
Ng Swee Fung,Aminah Ahmad,Zoharah Omar
International Journal of Academic Research in Business and Social Sciences , 2012,
Abstract: The growing interest in understanding the interface of work and family roles, in particular work-family enrichment, and its antecedents and outcomes, has stimulated the development of a mediation model. The mediation model developed includes dispositional factors (optimism, self-efficacy) as antecedents, job satisfaction as the outcome, and work-family enrichment as the mediator. This present model is developed based on the conservation of resources theory (Hobfoll, 1989), the model of work-family enrichment (Greenhaus & Powell, 2006) and the social exchange theory (Blau, 1964). This model presents the mechanism of how dispositional factors could influence job satisfaction among employees through work-family enrichment.
Experience sharing in infusing the concept and knowledge of DNA into primary formal curriculum
Pelly Pui-Yee NG,Leo Sun-Wai FUNG
Asia-Pacific Forum on Science Learning and Teaching , 2006,
Abstract: Sharing in the experience of school-based curriculum development: teaching primary students the concept and knowledge of DNA during regular class time. From evaluation on teaching content to students' performance to analysis of learning outcomes to parents' feedback to teacher's self-reflection, conclusion can be drawn that the infusion of DNA concept and knowledge into the primary formal curriculum is successful and worth disseminating the implementation to other primary schools.
The Ethanol Extract of Fructus trichosanthis Promotes Fetal Hemoglobin Production via p38 MAPK Activation and ERK Inactivation in K562 Cells
Hui Li,Chun Hay Ko,Suk Ying Tsang,Ping Chung Leung,Ming Chui Fung,Kwok Pui Fung
Evidence-Based Complementary and Alternative Medicine , 2011, DOI: 10.1093/ecam/neq022
Abstract: Pharmacological stimulation of fetal hemoglobin (HbF) expression may be a promising approach for the treatment of beta-thalassemia. In this study, the effects of Fructus trichosanthis (FT) were investigated in human erythroleukemic K562 cells for their gamma-globin mRNA and HbF-induction activities. The role of signaling pathways, including extracellular regulated protein kinase (ERK) and p38 mitogen-activated protein kinase (MAPK), was also investigated. It was found that the ethanol extract of FT significantly increased gamma-globin mRNA and HbF levels, determined by real-time reverse transcription polymerase chain reaction and enzyme linked immunosorbent assay, respectively, in dose- and time-dependent manner. Total Hb (THb) levels were also elevated in the concentrations without cytotoxicity (<80?μg?mL?1). Pre-treatment with p38 MAPK inhibitor SB203580 blocked the stimulatory effects of FT extract in total and HbF induction. In contrast, no change in HbF was observed when treated with ERK inhibitor PD98059. Furthermore, FT ethanol extract activated p38 MAPK and inhibited ERK signaling pathways in K562 cells, as revealed in western blotting analysis. In addition, SB203580 significantly abolished p38 MAPK activation when the cells were treated with FT. In summary, the ethanol extract of FT was found to be a potent inducer of HbF synthesis in K562 cells. The present data delineated the role of ERK and p38 MAPK signaling as molecular targets for pharmacologic stimulation of HbF production upon FT treatment. 1. Introduction -Thalassemia is an inherited autosomal recessive disease commonly found in the Mediterranean, southeast Asia and southern China [1, 2]. It is caused by mutations in the beta-globin gene on chromosome 11p15.5. Patients suffer great morbidity and mortality, including transfusion-dependent anemia with concomitant iron overload, hepatosplenomegaly and ineffective erythropoiesis [3]. Increased fetal hemoglobin (HbF) production can compensate for the shortfall of adult Hb (HbA) synthesis in -thalassemia patients [4]. Some chemotherapeutic agents, such as hydroxyurea (HU) and 5-azacytidine have been used to enhance HbF production [5, 6], but myelotoxicity, fear of long-term carcinogenesis and only modest responses to treatment have limited the clinical usefulness of these agents [7, 8]. In view of the lack of good therapeutic agents for this disease, we established a rational strategy on discovering new interventions to reactivate HbF production in Chinese herbal medicines by using human erythroleukemia cell line K562 as screening platform.
The Antiproliferative Activity of Sclerotia of Lignosus rhinocerus (Tiger Milk Mushroom)
M. L. Lee,N. H. Tan,S. Y. Fung,C. S. Tan,S. T. Ng
Evidence-Based Complementary and Alternative Medicine , 2012, DOI: 10.1155/2012/697603
Abstract: Lignosus rhinocerus, the tiger milk mushroom, is one of the most important medicinal mushrooms used by the indigenous people of Southeast Asia and China. It has been used to treat breast cancer. A cold water extract (LR-CW) prepared from the sclerotia of L. rhinocerus cultivar was found to exhibit antiproliferative activity against human breast carcinoma (MCF-7) and human lung carcinoma (A549), with IC50 of 96.7 μg/mL and 466.7 μg/mL, respectively. In comparison, LR-CW did not show significant cytotoxicity against the two corresponding human normal cells, 184B5 (human breast cell) and NL 20 (human lung cell). DNA fragmentation studies suggested that the cytotoxic action of LR-CW against cancer cells is mediated by apoptosis. Sephadex G-50 gel filtration fractionation of LR-CW yielded a high-molecular-weight and a low-molecular-weight fraction. The high-molecular-weight fraction contains mainly carbohydrate (68.7%) and small amount of protein (3.6%), whereas the low-molecular-weight fraction contains 31% carbohydrate and was devoid of protein. Only the high-molecular-weight fraction exhibited antiproliferative activity against cancer cells, with IC50 of 70.0 μg/mL and 76.7 μg/mL, respectively. Thus, the cytotoxic action of the LR-CW is due to the high-molecular-weight fraction, either the proteins or protein-carbohydrate complex.
Role and outcome of conventional surgery in the treatment of pyogenic liver abscess in the modern era of minimally invasive therapy
Simon Siu-Man Ng, Janet Fung-Yee Lee, Paul Bo-San Lai
World Journal of Gastroenterology , 2008,
Abstract: AIM: To evaluate the role and outcome of conventional surgery in the treatment of pyogenic liver abscess in the modern era of minimally invasive therapy.METHODS: The medical records of thirteen patients with pyogenic liver abscess who underwent surgical treatment between January 1995 and December 2002 were retrospectively reviewed to determine the clinical presentation, indication and nature of surgery, and outcome of surgery.RESULTS: The patients were predominantly women (10/13) with a mean age of 65 ± 17 years. Their main presenting symptoms were abdominal pain (100%) and fever (77%). The aetiologies included biliary (n = 6), cryptogenic (n = 3), portal (n = 2), and trauma (n = 2). Seven patients underwent percutaneous drainage as the initial treatment. Of these, three patients developed peritonitis secondary to peritoneal spillage. Another four patients failed to respond because of multiloculation. Salvage surgery was required in these patients. Six patients proceeded to straight laparotomy: two had marked sepsis and multiloculated abscess that precluded percutaneous drainage, and four presented with peritonitis of uncertain pathology. Surgical procedures included deroofment and drainage (n = 9), liver resection (n = 3), peritoneal lavage (n = 2), cholecystectomy (n = 4), and exploration of common bile duct (n = 2). One patient required reoperation because of bleeding. Three patients required further percutaneous drainage after surgery. The overall mortality was 46%. Four patients died of multiorgan failure and two patients died of pulmonary embolism.CONCLUSION: Surgical treatment of pyogenic liver abscess is occasionally needed when percutaneous drainage has failed due to various reasons. Mortality rate in this group of patients has remained high.
Genetic Susceptibility to Refractive Error: Association of Vasoactive Intestinal Peptide Receptor 2 (VIPR2) with High Myopia in Chinese
Wai Chi Yiu, Maurice K. H. Yap, Wai Yan Fung, Po Wah Ng, Shea Ping Yip
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0061805
Abstract: Myopia is the most common ocular disease worldwide. We investigated the association of high myopia with the common single nucleotide polymorphisms (SNPs) of five candidate genes – early growth response 1 (EGR1), v-fos FBJ murine osteosarcoma viral oncogene homolog (FOS), jun oncogene (JUN), vasoactive intestinal peptide (VIP), and vasoactive intestinal peptide receptor 2 (VIPR2). We recruited 1200 unrelated Chinese subjects with 600 cases (spherical equivalent ≤?8.00 diopters) and 600 controls (spherical equivalent within ±1.00 diopter). A discovery sample set was formed from 300 cases and 300 controls, and a replication sample set from the remaining samples. Tag SNPs were genotyped for the discovery sample set, and the most significant haplotypes and their constituent SNPs were followed up with the replication sample set. The allele and haplotype frequencies in cases and controls were compared by logistic regression adjusted for sex and age to give Pa values, and multiple comparisons were corrected by permutation test to give Paemp values. Odd ratios (OR) were calculated accordingly. In the discovery phase, EGR1, JUN and VIP did not show any significant association while FOS and VIPR2 demonstrated significant haplotype association with high myopia. In the replication phase, the haplotype association for VIPR2 was successfully replicated, but not FOS. In analysis combining both sample sets, the most significant association signals of VIPR2 were the single marker rs2071625 (Pa = 0.0008, Paemp = 0.0046 and OR = 0.75) and the 4-SNP haplotype window rs2071623-rs2071625-rs2730220-rs885863 (omnibus test, Pa = 9.10e-10 and Paemp = 0.0001) with one protective haplotype (GGGG: Paemp = 0.0002 and OR = 0.52) and one high-risk haplotype (GAGA: Paemp = 0.0027 and OR = 4.68). This 4-SNP haplotype window was the most significant in all sample sets examined. This is the first study to suggest a role of VIPR2 in the genetic susceptibility to high myopia. EGR1, JUN, FOS and VIP are unlikely to be important in predisposing humans to high myopia.
Page 1 /6097
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.