9 research outputs found
Foreign ownership restrictions and share prices in the China capital market.
This paper looks briefly at the development of the Shanghai and Shenzhen stock markets in the context of China's goal to attract foreign capital to modernise and integrate its economy to the global economy. The analysis of the stock returns revealed that the returns on B shares in Shenzhen generally exhibit little or no correlation with international factors while those in Shanghai do exhibit some correlation. In addition, liquidity as measured by the ratio of the volume of B shares to total volume of A and B shares only explain the returns of Shenzhen B shares. The only factor that explains the returns on both Shanghai and Shenzhen B shares is the effects of firm size. Generally, the results suggest that the Shenzhen B shares have some diversification value while Shanghai B shares are not totally segmented from international factors.Master of Business Administration (Accountancy
A lab-on-a-chip for detection of nerve agent sarin in blood
Sarin (C4H10FO2P,O-isopropyl methylphosphonofluoridate) is a colourless, odourless and highly toxic phosphonate that acts as a cholinesterase inhibitor and disrupts neuromuscular transmission. Sarin and related phosphonates are chemical warfare agents, and there is a possibility of their application in a military or terrorist attack. This paper reports a lab-on-a-chip device for detecting a trace amount of sarin in a small volume of blood. The device should allow early detection of sarin exposure during medical triage to differentiate between those requiring medical treatment from mass psychogenic illness cases. The device is based on continuous-flow microfluidics with sequential stages for lysis of whole blood, regeneration of free nerve agent from its complex with blood cholinesterase, protein precipitation, filtration, enzyme-assisted reaction and optical detection. Whole blood was first mixed with a nerve gas regeneration agent, followed by a protein precipitation step. Subsequently, the lysed product was filtered on the chip in two steps to remove particulates and fluoride ions. The filtered blood sample was then tested for trace levels of regenerated sarin using immobilised cholinesterase on the chip. Activity of immobilised cholinesterase was monitored by the enzyme-assisted reaction of a substrate and reaction of the end-product with a chromophore. Resultant changes in chromophore-induced absorbance were recorded on the chip using a Z-shaped optical window. Loss of enzyme activity obtained prior and after passage of the treated blood sample, as shown by a decrease in recorded absorbance values, indicates the presence of either free or regenerated sarin in the blood sample. The device was fabricated in PMMA (polymethylmethacrylate) using CO2-laser micromachining. This paper reports the testing results of the different stages, as well as the whole device with all stages in the required assay sequence. The results demonstrate the potential use of a field-deployable hand-held device for point-of-care triage of suspected nerve agent casualties.Accepted versio
Large axial actuation of pre-stretched tubular dielectric elastomer and use of oil encapsulation to enhance dielectric breakdown strength
Rolled dielectric elastomer actuators (DEAs) are subjected to necking and non-uniform deformation upon pre-stress relaxation. Though rolled up from flat DEAs, they performed much poorer than the flat ones. Their electrically induced axial strains were previously reported as not more than 37.3%, while the flat ones produced greater than 100% strain. Often, the rolled DEAs succumb to premature breakdown before they can realize the full actuation potential like the flat ones do. This study shows that oil encapsulation, together with large hoop pre-stretch, helps single-wound rolled DEAs, which are also known as tubular DEAs, suppress premature breakdown. Consequently, the oil-encapsulated tubular DEAs can sustain higher electric fields, and thus produce larger isotonic strain and higher isometric stress change. Under isotonic testing, they sustained very high electric fields of up to 712.7 MV m−1, which is approximately 50% higher than those of the dry tubular DEAs. They produced up to 55.4% axial isotonic strain despite axially stiffening by the passive oil capsules. In addition, due to the use of large hoop pre-stretch, even the dry tubular DEAs without oil encapsulation achieved a very large axial strain of up to 84.2% compared to previous works. Under isometric testing, the oil-encapsulated tubular DEA with enhanced breakdown strength produced an axial stress change of up to nearly 0.6 MPa, which is 114% higher than that produced by the dry ones. In conclusion, the oil encapsulation and large pre-stretch help realize fuller actuation potential of tubular dielectric elastomer, which is subjected to initially non-uniform deformation.Accepted versio
Large-strain, high-stress tubular dielectric elastomer actuator with high pre-stretch and oil encapsulation
Rolled dielectric elastomer actuators (DEA), which are prepared by rolling up a flat dielectric elastomer , are subjected to non-homogenous deformation and thus does not perform as well as the flat ones. Typically, the rolled ones reported actuation of not more than 37.3% axial strain; whereas the flat one undergoing pure-shear deformation reported much greater actuation . This study shows that oil encapsulation helps the rolled DEA suppress pre-mature breakdown. Under isotonic test, oil-encapsulated tubular DEAs sustain very high electric field of up to 712.0 MV/m, which is 50% higher than that of the dry DEAs. Hence, it can produce up to 50% axial strain while deforming the passive oil capsules. In addition, it produces an isometric stress up to nearly 0.6 MPa, 114% higher than that of the dry one.Published versio
Nerolidol: A Sesquiterpene Alcohol with Multi-Faceted Pharmacological and Biological Activities
Nerolidol (3,7,11-trimethyl-1,6,10-dodecatrien-3-ol) is a naturally occurring sesquiterpene alcohol that is present in various plants with a floral odor. It is synthesized as an intermediate in the production of (3E)-4,8-dimethy-1,3,7-nonatriene (DMNT), a herbivore-induced volatile that protects plants from herbivore damage. Chemically, nerolidol exists in two geometric isomers, a trans and a cis form. The usage of nerolidol is widespread across different industries. It has been widely used in cosmetics (e.g., shampoos and perfumes) and in non-cosmetic products (e.g., detergents and cleansers). In fact, U.S. Food and Drug Administration (FDA) has also permitted the use of nerolidol as a food flavoring agent. The fact that nerolidol is a common ingredient in many products has attracted researchers to explore more medicinal properties of nerolidol that may exert beneficial effect on human health. Therefore, the aim of this review is to compile and consolidate the data on the various pharmacological and biological activities displayed by nerolidol. Furthermore, this review also includes pharmacokinetic and toxicological studies of nerolidol. In summary, the various pharmacological and biological activities demonstrated in this review highlight the prospects of nerolidol as a promising chemical or drug candidate in the field of agriculture and medicine
The use of Genous Endothelial progenitor cell (EPC) capture stent in acute ST-Elevation myocardial infarction (STEMI): Angiographic follow-up at 6 months.
European Society of Cardiology Congres
Integrative Profiling of T790M-Negative EGFR-Mutated NSCLC Reveals Pervasive Lineage Transition and Therapeutic Opportunities
Purpose: Despite the established role of EGFR tyrosine kinase inhibitors (TKIs) in EGFR-mutated NSCLC, drug resistance inevitably ensues, with a paucity of treatment options especially in EGFRT790M-negative resistance. Experimental Design: We performed whole-exome and transcriptome analysis of 59 patients with first- and second-generation EGFR TKI-resistant metastatic EGFR-mutated NSCLC to characterize and compare molecular alterations mediating resistance in T790M-positive (T790M(+)) and -negative (T790M(-)) disease. Results: Transcriptomic analysis revealed ubiquitous loss of adenocarcinoma lineage gene expression in T790M(-) tumors, orthogonally validated using multiplex IHC. There was enrichment of genomic features such as TP53 alterations, 3q chromosomal amplifications, whole-genome doubling and nonaging mutational signatures in T790M(-) tumors. Almost half of resistant tumors were further classified as immune(hot), with clinical outcomes conditional on immune cell-infiltration state and T790M status. Finally, using a Bayesian statistical approach, we explored how T790M(-) and T790M(+) disease might be predicted using comprehensive genomic and transcriptomic profiles of treatment-naive patients. Conclusions: Our results illustrate the interplay between genetic alterations, cell lineage plasticity, and immune microenvironment in shaping divergent TKI resistance and outcome trajectories in EGFR-mutated NSCLC. Genomic and transcriptomic profiling may facilitate the design of bespoke therapeutic approaches tailored to a tumor's adaptive potential
Results from a Patient-Based Health Education Intervention in Reducing Antibiotic Use for Acute Upper Respiratory Tract Infections in the Private Sector Primary Care Setting in Singapore
We investigated the efficacy of patient-targeted education in reducing antibiotic prescriptions for upper respiratory tract infections (URTIs) among adults in the private primary care setting in Singapore. Our randomized controlled trial enrolled patients aged 21 years and above presenting at general practitioner (GP) clinics with URTI symptoms for 7 days or less. Intervention arm patients were verbally educated via pamphlets about the etiology of URTIs, the role of antibiotics in treating URTIs, and the consequences of inappropriate antibiotic use. Control arm patients were educated on influenza vaccinations. Both arms were compared regarding the proportions prescribed antibiotics and the patients' postconsultation views. A total of 914 patients consulting 35 doctors from 24 clinics completed the study (457 in each arm). The demographics of patients in both arms were similar, and 19.1% were prescribed an antibiotic, but this varied from 0% to 70% for individual GPs. The intervention did not significantly reduce antibiotic prescriptions (odds ratio [OR], 1.20; 95% confidence interval [CI], 0.83–1.73) except in patients of Indian ethnicity (OR, 0.28; 95% CI, 0.09–0.93). Positive associations between the intervention and the view that antibiotics were not needed most of the time for URTIs (P = 0.047) and on being worried about the side effects of antibiotics (P = 0.018) were restricted to the Indian subgroup. GPs in limited liability partnerships or clinic chains prescribed less (OR, 0.36; 95% CI, 0.14 to 0.92), while certain inappropriate patient responses were associated with the receipt of antibiotics. Follow-up studies to investigate differences in responses to educational programs between ethnicities and to explore GP-targeted interventions are recommended.NMRC (Natl Medical Research Council, S’pore)MOH (Min. of Health, S’pore)Published versio