62 results on '"Fung KK"'
Search Results
2. The role of spiral CT in pelvic trauma management
- Author
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Cheung, EC and Fung, KK
- Published
- 1999
3. Foetal dose reduction in CT pelvimetry by PA scanning method
- Author
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Fung, HS, Cheung, YT, Chan, CC, and Fung, KK
- Published
- 1997
4. Randomized Trial of Radiotherapy Plus Concurrent-Adjuvant Chemotherapy vs Radiotherapy Alone for Regionally Advanced Nasopharyngeal Carcinoma.
- Author
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Lee AW, Tung SY, Chua DT, Ngan RK, Chappell R, Tung R, Siu L, Ng WT, Sze WK, Au GK, Law SC, O'Sullivan B, Yau TK, Leung TW, Au JS, Sze WM, Choi CW, Fung KK, Lau JT, and Lau WH
- Published
- 2010
- Full Text
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5. Building and testing of a robotic intervention framework to enhancing the social engagement of children with autism spectrum disorder.
- Author
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Chung EY, Sin KK, and Chow DH
- Abstract
Purpose: Humanoid robot intervention programmes for children with autism spectrum disorder (ASD) are being developed rapidly. This study aimed to develop and test a robotic intervention framework for children with ASD to ensure best practice., Methods: In Phase I of this study, an initial framework was built based on a scoping review. This review aimed to identify the core elements conducive to effective robotic intervention programmes for children with ASD. In Phase II, the content of the initial framework was verified using a case study approach in a real-life setting., Results: The robotic intervention framework, which comprised three domains, was built and tested. The three domains were robot-, child-, and programme-related factors. Elements within each domain were identified and verified in real-life contexts., Conclusions: The proposed framework will enhance evidence-based practice in robotic intervention programmes. However, further clinical testing is warranted to enhance the efficacy and validity of this framework. A good programme design incorporating all essential elements for effective intervention will ensure the success of the training programme for children with ASD.
- Published
- 2024
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6. Comparing the Effects of Aqua- and Land-Based Active Cooldown Exercises on Muscle Soreness and Sport Performance: A Randomized Crossover Study.
- Author
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Chin EC, Chung-Nam Lai S, Tsang SF, Ho-Ngai Chung S, Wong YL, Sran N, Fung KK, and Sun F
- Abstract
Objective: Limited research has directly compared the effectiveness of aqua- and land-based exercises for postexercise recovery. This study aimed to fill this gap by comparing the effects of these 2 types of exercises on postexercise recovery., Methods: Sixteen male college athletes participated in an 8-day experimental study. The initial 2 days were dedicated to determining the intensity levels for the muscle-damaging exercise and recovery jogging. In a crossover design, participants underwent 2 sets of experimental trials. They were randomly assigned to either an aqua or land recovery intervention for days 3 to 5, and after a 1-week washout period they switched to the opposite intervention for days 6 to 8. Muscle soreness, creatine kinase, anaerobic performance, countermovement-jump height, and flexibility were assessed at different time points: baseline, immediately after downhill running, within 1 hour after jogging, and 24 hours and 48 hours after aqua or land jogging., Results: Significant group × time interaction effects were detected in the perceived soreness of the hamstring and quadriceps. However, the post hoc analysis showed no significant difference between aqua and land jogging groups. No significant group × time interaction effect was observed in creatine kinase, anaerobic performance, countermovement-jump height, or flexibility., Conclusion: Aqua and land jogging have similar recovery effects on muscle soreness and performance-based parameters.
- Published
- 2024
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7. Plastic Bronchitis in an Adult After COVID-19 Infection.
- Author
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Chan KF, Fung KK, and Ho PL
- Subjects
- Humans, SARS-CoV-2, Male, Middle Aged, Tomography, X-Ray Computed, Adult, Female, COVID-19 complications, Bronchitis diagnosis, Bronchitis etiology, Bronchitis virology
- Published
- 2024
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8. Presession mood induction in therapists: Effects on therapist empathy.
- Author
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Chui H, Luk S, Liu F, Fung KK, and Loung RPY
- Subjects
- Humans, Professional-Patient Relations, Psychotherapeutic Processes, Affect, Empathy, Psychotherapy methods
- Abstract
Previous studies show that therapist mood is associated with psychotherapy processes, but the observational nature of these studies does not allow for causal inference. It is also unclear if other therapist characteristics, such as therapist trait empathy, moderate the relation between therapist mood and process variables. Thirty-four therapists and volunteer client dyads participated in three weekly counseling sessions. Before each session, therapists were induced to experience one of three moods, elation, depression, or neutral, in a counterbalanced order, using a combination of music and the Velten method. After each session, clients rated therapist empathy and session quality, therapists rated session quality, and observers rated therapist empathy using videotapes. Electrocardiogram was collected from therapists and clients during the session to assess heart rate synchrony as an indicator of therapist empathy. Therapist trait empathy moderated the effect of mood induction on observer-rated therapist empathy, such that when induced to experience elation, therapists with high trait empathy were observed to be more empathic, whereas therapists with low trait empathy were observed to be less empathic. Therapists of different trait empathy levels did not differ on observer-rated empathy when induced to experience depression or neutral mood. No significant effect of mood induction was found for client-rated empathy, client- and therapist-rated session quality, or heart rate synchrony. The experimental design offers preliminary evidence that therapist presession mood may influence the psychotherapy process. The findings are explained in light of empathy amplification and empathy attenuation hypotheses in relation to positive emotion. Practice and research implications are discussed. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
- Published
- 2023
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9. Referring students for professional psychological help: A qualitative study of teachers' experience in Hong Kong.
- Author
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Chui H, Luk S, Fung KK, and Huang Y
- Subjects
- Humans, Hong Kong, Schools, School Teachers psychology, Students psychology, Educational Personnel
- Abstract
Teachers have frequent interaction with students and are well positioned to refer students for mental health assistance when needed. Twelve secondary schoolteachers in Hong Kong were interviewed about their experience referring students to mental health professionals (MHPs). Using consensual qualitative research, multiple factors were found to influence teachers' referral decisions, including problem severity, students' willingness, stigma of help-seeking, parent/guardian's beliefs, teacher-parent/guardian relationship, MHPs' effectiveness and availability, quality of interaction with MHPs, and teachers' self-efficacy in handling student issues. Based on the findings, we propose a conceptual model of factors influencing teachers' referral decisions. Implications for research, practice, and training are discussed., (Copyright © 2023 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2023
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10. Are the severity of obstruction and the apnea-hypopnea index related to orofacial anatomy in children with obstructive sleep apnea? a kinetic MRI study.
- Author
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Savoldi F, Fung KK, Mak WS, Kan EY, Yang Y, Kwok KL, and Gu M
- Subjects
- Adolescent, Humans, Child, Retrospective Studies, Oropharynx diagnostic imaging, Magnetic Resonance Imaging methods, Sleep Apnea, Obstructive diagnostic imaging, Airway Obstruction diagnostic imaging
- Abstract
Objectives: The proportionality between anatomical characteristics and disease severity in children and adolescents with obstructive sleep apnea (OSA) has not been well characterized. The present study investigated the relationship between the dentoskeletal and oropharyngeal features of young patients with OSA and either the apnea-hypopnea index (AHI) or the amount of upper airway obstruction., Methods: MRI of 25 patients (8- to 18-year-old) with OSA (mean AHI = 4.3 events/h) was retrospectively analyzed. Sleep kinetic MRI (kMRI) was used to assess airway obstruction, and static MRI (sMRI) was used to assess dentoskeletal, soft tissue, and airway parameters. Factors related to AHI and obstruction severity were identified with multiple linear regression (significance level α = 0.05)., Results: As evidenced by kMRI, circumferential obstruction was present in 44% of patients, while laterolateral and anteroposterior was present in 28%; as evidenced by kMRI, obstructions were retropalatal in 64% of cases and retroglossal in 36% (no nasopharyngeal obstructions); kMRI showed a higher prevalence of retroglossal obstructions compared to sMRI( p = 0.037); the main obstruction airway area was not related to AHI; the maxillary skeletal width was related to AHI ( β = -0.512, p = 0.007) and obstruction severity ( β = 0.625, p = 0.002); and the retropalatal width was related to AHI ( β = -0.384, p = 0.024) and obstruction severity ( β = 0.519, p = 0.006)., Conclusions: In children and adolescents, the severity of OSA and obstruction were inversely proportional to the maxillary basal width and retropalatal airway width. Further studies are needed to assess the benefits of targeted clinical treatments widening the transverse dimension of these structures.
- Published
- 2023
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11. Access to Information and Communication Technology, Digital Skills, and Perceived Well-Being among Older Adults in Hong Kong.
- Author
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Fung KK, Hung SS, Lai DWL, Shum MHY, Fung HW, and He L
- Subjects
- Humans, Male, Aged, Hong Kong, Communication, Information Technology, Internet, Access to Information, Digital Technology
- Abstract
Population aging is a major concern worldwide. Active aging should be promoted by increasing the social participation of older adults and enabling them to remain involved in the community. Research has demonstrated the utility of digital resources for addressing the needs of older adults, which include networking, entertaining, and seeking health-related information. However, the digital divide among older adults (i.e., the "gray digital divide") is increasingly being recognized as a social problem that may be related to poor well-being. To obtain updated local data on the prevalence of Internet access and usage and their relationship with perceived well-being, we conducted telephone interviews with a random sample of 1018 older adults in Hong Kong from January to July 2021 (This research has received funding support from the Interdisciplinary Research Matching Scheme, Hong Kong Baptist University). We found that only 76.5% of the participants had Internet access at home, a mobile phone data plan, or both, whereas 36.3% had never used Internet services and 18.2% had no digital devices. A younger age, male gender, higher education level, living with others, and higher self-perceived social class were associated with material access to digital devices and everyday use of Internet services. Participants who accessed the Internet every day had higher levels of life satisfaction and self-rated physical and mental health than those who rarely or never used the Internet. Hierarchical multiple regression analysis revealed that digital skills were significantly associated with self-rated mental health even when controlling for demographic variables (including age, gender, education level, and self-perceived social class). This study contributes to the limited body of literature on the relationship between Internet use, digital skills, and perceived well-being. Our findings highlight the importance of addressing the digital divide even in cities with high penetration of information and communication technology, such as Hong Kong. We also discuss our insights into the use of timely interventions for older adults to address the gray digital divide.
- Published
- 2023
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12. Genomic Investigation of Salmonella Typhi in Hong Kong Revealing the Predominance of Genotype 3.2.2 and the First Case of an Extensively Drug-Resistant H58 Genotype.
- Author
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Li X, Cao H, Chen JH, Ng YZ, Fung KK, Cheng VC, and Ho PL
- Abstract
Typhoid fever is a notable disease in Hong Kong. We noticed two local cases of typhoid fever caused by Salmonella Typhi within a two-week period in late 2022, which had no apparent epidemiological linkage except for residing in the same region of Hong Kong. A phylogenetic study of Salmonella Typhi isolates from Hong Kong Island from 2020 to 2022 was performed, including a whole-genome analysis, the typing of plasmids, and the analysis of antibiotic-resistance genes (ARGs), to identify the dominant circulating strain and the spread of ARGs. A total of seven isolates, from six local cases and an imported case, were identified from positive blood cultures in two hospitals in Hong Kong. Five antibiotic-sensitive strains of genotype 3.2.2 were found, which clustered with another 30 strains originating from Southeast Asia. Whole-genome sequencing revealed clonal transmission between the two index cases. The remaining two local cases belong to genotype 2.3.4 and genotype 4.3.1.1.P1 (also known as the H58 lineage). The genotype 4.3.1.1.P1 strain has an extensively drug-resistant (XDR) phenotype (co-resistance to ampicillin, chloramphenicol, ceftriaxone, ciprofloxacin, and co-trimoxazole). Although the majority of local strains belong to the non-H58 genotype 3.2.2 with a low degree of antibiotic resistance, the introduction of XDR strains with the global dissemination of the H58 lineage remains a concern.
- Published
- 2023
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13. Community social work in Hong Kong during COVID-19: Intervention strategies to address social injustices.
- Author
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Fung KK, Hung SL, and Chan YC
- Abstract
In Hong Kong, professional social workers made their presence felt when they delivered a variety of services at the height of the pandemic. Social workers who were working in community development projects or who had adopted community work approaches have become the major service providers when the availability and accessibility of other types of social services have been seriously impeded. This article reports on a qualitative research study conducted to examine (1) how community social workers have planned and implemented services, (2) their use of information and communication technologies (ICTs), and (3) ideas for addressing injustices in disaster management work., Competing Interests: The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the Research Grants Council under the General Research Grant, Hong Kong [GRF16151116]., (© The Author(s) 2022.)
- Published
- 2023
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14. Flavin-Containing Monooxygenase 3 (FMO3) Is Critical for Dioxin-Induced Reorganization of the Gut Microbiome and Host Insulin Sensitivity.
- Author
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Massey W, Osborn LJ, Banerjee R, Horak A, Fung KK, Orabi D, Chan ER, Sangwan N, Wang Z, and Brown JM
- Abstract
Exposure to some environmental pollutants can have potent endocrine-disrupting effects, thereby promoting hormone imbalance and cardiometabolic diseases such as non-alcoholic fatty liver disease (NAFLD), diabetes, and cardiorenal diseases. Recent evidence also suggests that many environmental pollutants can reorganize the gut microbiome to potentially impact these diverse human diseases. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is among the most potent endocrine-disrupting dioxin pollutants, yet our understanding of how TCDD impacts the gut microbiome and systemic metabolism is incompletely understood. Here, we show that TCDD exposure in mice profoundly stimulates the hepatic expression of flavin-containing monooxygenase 3 ( Fmo3 ), which is a hepatic xenobiotic metabolizing enzyme that is also responsible for the production of the gut microbiome-associated metabolite trimethylamine N-oxide (TMAO). Interestingly, an enzymatic product of FMO3 (TMAO) has been associated with the same cardiometabolic diseases that these environmental pollutants promote. Therefore, here, we examined TCDD-induced alterations in the gut microbiome, host liver transcriptome, and glucose tolerance in Fmo3
+/+ and Fmo3-/- mice. Our results show that Fmo3 is a critical component of the transcriptional response to TCDD, impacting the gut microbiome, host liver transcriptome, and systemic glucose tolerance. Collectively, this work uncovers a previously underappreciated role for Fmo3 in integrating diet-pollutant-microbe-host interactions.- Published
- 2022
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15. Gut microbial trimethylamine is elevated in alcohol-associated hepatitis and contributes to ethanol-induced liver injury in mice.
- Author
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Helsley RN, Miyata T, Kadam A, Varadharajan V, Sangwan N, Huang EC, Banerjee R, Brown AL, Fung KK, Massey WJ, Neumann C, Orabi D, Osborn LJ, Schugar RC, McMullen MR, Bellar A, Poulsen KL, Kim A, Pathak V, Mrdjen M, Anderson JT, Willard B, McClain CJ, Mitchell M, McCullough AJ, Radaeva S, Barton B, Szabo G, Dasarathy S, Garcia-Garcia JC, Rotroff DM, Allende DS, Wang Z, Hazen SL, Nagy LE, and Brown JM
- Subjects
- Animals, Ethanol adverse effects, Female, Mice, Mice, Inbred C57BL, Random Allocation, Bacteria metabolism, Chemical and Drug Induced Liver Injury, Chronic metabolism, Gastrointestinal Microbiome, Hepatitis metabolism, Methylamines metabolism
- Abstract
There is mounting evidence that microbes residing in the human intestine contribute to diverse alcohol-associated liver diseases (ALD) including the most deadly form known as alcohol-associated hepatitis (AH). However, mechanisms by which gut microbes synergize with excessive alcohol intake to promote liver injury are poorly understood. Furthermore, whether drugs that selectively target gut microbial metabolism can improve ALD has never been tested. We used liquid chromatography tandem mass spectrometry to quantify the levels of microbe and host choline co-metabolites in healthy controls and AH patients, finding elevated levels of the microbial metabolite trimethylamine (TMA) in AH. In subsequent studies, we treated mice with non-lethal bacterial choline TMA lyase (CutC/D) inhibitors to blunt gut microbe-dependent production of TMA in the context of chronic ethanol administration. Indices of liver injury were quantified by complementary RNA sequencing, biochemical, and histological approaches. In addition, we examined the impact of ethanol consumption and TMA lyase inhibition on gut microbiome structure via 16S rRNA sequencing. We show the gut microbial choline metabolite TMA is elevated in AH patients and correlates with reduced hepatic expression of the TMA oxygenase flavin-containing monooxygenase 3 (FMO3). Provocatively, we find that small molecule inhibition of gut microbial CutC/D activity protects mice from ethanol-induced liver injury. CutC/D inhibitor-driven improvement in ethanol-induced liver injury is associated with distinct reorganization of the gut microbiome and host liver transcriptome. The microbial metabolite TMA is elevated in patients with AH, and inhibition of TMA production from gut microbes can protect mice from ethanol-induced liver injury., Competing Interests: RH, TM, AK, VV, NS, EH, RB, AB, KF, WM, CN, DO, LO, RS, MM, AB, KP, AK, VP, MM, JA, BW, CM, MM, AM, SR, BB, GS, SD, JG, DR, DA, LN, JB No competing interests declared, ZW Kaiser Permanente (CME lecture sessions) Advisory Board for Incyte (on treatment of cholangiocarcinoma), SH Z.W. report being named as co-inventor on pending and issued patents held by the Cleveland Clinic relating to cardiovascular diagnostics and therapeutics. Z.W. reports being eligible to receive royalty payments for inventions or discoveries related to cardiovascular diagnostics or therapeutics from Zehna Therapeutics, Cleveland Heart Lab, a wholly owned subsidiary of Quest Diagnostics, and Procter & Gamble, (© 2022, Helsley et al.)
- Published
- 2022
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16. Gut microbe-targeted choline trimethylamine lyase inhibition improves obesity via rewiring of host circadian rhythms.
- Author
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Schugar RC, Gliniak CM, Osborn LJ, Massey W, Sangwan N, Horak A, Banerjee R, Orabi D, Helsley RN, Brown AL, Burrows A, Finney C, Fung KK, Allen FM, Ferguson D, Gromovsky AD, Neumann C, Cook K, McMillan A, Buffa JA, Anderson JT, Mehrabian M, Goudarzi M, Willard B, Mak TD, Armstrong AR, Swanson G, Keshavarzian A, Garcia-Garcia JC, Wang Z, Lusis AJ, Hazen SL, and Brown JM
- Subjects
- Animals, Choline administration & dosage, Choline metabolism, Diet, High-Fat, Enzyme Inhibitors pharmacology, Leptin deficiency, Lyases drug effects, Male, Methylamines metabolism, Mice, Mice, Inbred C57BL, Obesity genetics, Obesity microbiology, Choline analogs & derivatives, Circadian Rhythm drug effects, Gastrointestinal Microbiome drug effects, Obesity metabolism
- Abstract
Obesity has repeatedly been linked to reorganization of the gut microbiome, yet to this point obesity therapeutics have been targeted exclusively toward the human host. Here, we show that gut microbe-targeted inhibition of the trimethylamine N-oxide (TMAO) pathway protects mice against the metabolic disturbances associated with diet-induced obesity (DIO) or leptin deficiency ( Lep
ob/ob ). Small molecule inhibition of the gut microbial enzyme choline TMA-lyase (CutC) does not reduce food intake but is instead associated with alterations in the gut microbiome, improvement in glucose tolerance, and enhanced energy expenditure. We also show that gut microbial CutC inhibition is associated with reorganization of host circadian control of both phosphatidylcholine and energy metabolism. This study underscores the relationship between microbe and host metabolism and provides evidence that gut microbe-derived trimethylamine (TMA) is a key regulator of the host circadian clock. This work also demonstrates that gut microbe-targeted enzyme inhibitors have potential as anti-obesity therapeutics., Competing Interests: RS, CG, LO, WM, NS, AH, RB, DO, RH, AB, AB, CF, KF, FA, DF, AG, CN, KC, AM, JA, MM, MG, BW, TM, AA, GS, AK, AL, JB No competing interests declared, JB reports being eligible to receive royalty payments for inventions or discoveries related to cardiovascular therapeutics from the Proctor & Gamble Co, JG Employee of Procter & Gamble Company, ZW, SH reports being named as co-inventor on pending and issued patents 20200121615 held by the Cleveland Clinic relating to cardiovascular diagnostics and therapeutics. Reports being a paid consultant for Procter & Gamble, having received research funds from Procter & Gamble, Roche Diagnostics, and being eligible to receive royalty payments for inventions or discoveries related to cardiovascular diagnostics or therapeutics from Cleveland Heart Lab and Procter & Gamble, (© 2022, Schugar et al.)- Published
- 2022
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17. Enabling Factors of Subjective Well-being among Older Adults in Taiwan: The Welfare State and Beyond?
- Author
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Chung ML, Fung KK, and Liu CL
- Subjects
- Aged, Aging, Causality, Humans, Taiwan, Personal Satisfaction, Quality of Life
- Abstract
Given the increasing popularity of active aging agendas around the globe, the positive and sustainable impacts of welfare services on older adults attracted our attention. Previous studies based on social quality-related theories have examined the effects of different forms of social life mechanism on subjective well-being (SWB) as perceived by older adults. Yet, as evidence continues to emerge pointing to the positive relationship between quality of life and SWB, the present study aimed to incorporate the impacts of three enabling factors of active aging, namely social connectedness, economic support and technology acceptance, in explaining welfare service in terms of satisfaction, needs and awareness, a condition that may also facilitate SWB. The on-site face-to-face survey in Yunlin county was conducted through a rigorous systematic sampling method and ultimately received a valid sample comprising 600 Taiwanese older adults aged 65-101 years (mean age = 76.78 years). Our results showed that social connectedness, economic support and technology acceptance significantly and positively predict SWB among older adults. Moreover, SWB for older adults was found to be positively predicted by welfare satisfaction, which was also found to mediate the effect of economic support on SWB. Policy implications of these findings and future research recommendation are discussed.
- Published
- 2021
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18. Ductal adenocarcinoma of the prostate: a Hong Kong case series.
- Author
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Kan RW, Kan CF, Wong JH, Fu KK, Ng CF, and Chan SW
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- Aged, Aged, 80 and over, Carcinoma, Ductal epidemiology, Carcinoma, Ductal therapy, Combined Modality Therapy, Endoscopic Ultrasound-Guided Fine Needle Aspiration, Follow-Up Studies, Hong Kong epidemiology, Humans, Incidence, Male, Middle Aged, Prostatic Neoplasms epidemiology, Prostatic Neoplasms therapy, Rectum, Retrospective Studies, Carcinoma, Ductal diagnosis, Neoplasm Staging, Prostatic Neoplasms diagnosis
- Abstract
Objectives: To review and report our local experience in the management of ductal adenocarcinoma of the prostate., Methods: Retrospective review of patients diagnosed with ductal adenocarcinoma of the prostate in two regional urological centres in Hong Kong during 1995-2009. Clinical information, treatment and outcomes were retrieved for further analysis., Results: We identified 19 Chinese patients diagnosed with ductal adenocarcinoma of the prostate. Majority of our patients presented with retention of urine and haematuria. At presentation, seven patients were already at an advanced stage with evidence of rectal invasion or distant metastasis. The overall treatment outcome was poor with high failure rate after either local or systemic hormonal therapy., Conclusion: We observed a predilection of this tumour to be locally aggressive, and hence a relatively high incidence of intra-luminal growth and rectal invasion. We observed a high failure rate after either radical prostatectomy or hormonal therapy.
- Published
- 2014
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19. Modification of electronic properties of top-gated graphene devices by ultrathin yttrium-oxide dielectric layers.
- Author
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Wang L, Chen X, Wang Y, Wu Z, Li W, Han Y, Zhang M, He Y, Zhu C, Fung KK, and Wang N
- Subjects
- Electric Conductivity, Electromagnetic Fields, Equipment Design, Equipment Failure Analysis, Materials Testing, Particle Size, Conductometry instrumentation, Graphite chemistry, Membranes, Artificial, Nanostructures chemistry, Nanostructures ultrastructure, Yttrium chemistry
- Abstract
We report the structure characterization and electronic property modification of single layer graphene (SLG) field-effect transistor (FET) devices top-gated using ultrathin Y(2)O(3) as dielectric layers. Based on the Boltzmann transport theory within variant screening, Coulomb scattering is confirmed quantitatively to be dominant in Y(2)O(3)-covered SLG and a very few short-range impurities have been introduced by Y(2)O(3). Both DC transport and AC capacitance measurements carried out at cryogenic temperatures demonstrate that the broadening of Landau levels is mainly due to the additional charged impurities and inhomogeneity of carriers induced by Y(2)O(3) layers.
- Published
- 2013
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20. Asymmetric ZnO panel-like hierarchical architectures with highly interconnected pathways for free-electron transport and photovoltaic improvements.
- Author
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Shi Y, Zhu C, Wang L, Li W, Fung KK, and Wang N
- Abstract
Through a rapid and template-free precipitation approach, we synthesized an asymmetric panel-like ZnO hierarchical architecture (PHA) for photoanodes of dye-sensitized solar cells (DSCs). The two sides of the PHA are constructed differently using densely interconnected, mono-crystalline and ultrathin ZnO nanosheets. By mixing these PHAs with ZnO nanoparticles (NPs), we developed an effective and feasible strategy to improve the electrical transport and photovoltaic performance of the composite photoanodes of DSCs. The highly crystallized and interconnected ZnO nanosheets largely minimized the total grain boundaries within the composite photoanodes and thus served as direct pathways for the transport and effective collection of free electrons. Through low-temperature (200 °C) annealing, these novel composite photoanodes achieved high conversion efficiencies of up to 5.59% for ZnO-based quasi-solid DSCs., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2013
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21. A new technique of single portal endoscopic carpal tunnel release.
- Author
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Ip WY, Sweed TA, Fung KK, Tipoe GL, and Pun TS
- Subjects
- Humans, Treatment Outcome, Carpal Tunnel Syndrome surgery, Decompression, Surgical methods, Endoscopy, Median Nerve surgery
- Abstract
Since the first description of endoscopic carpal tunnel release (ECTR) in 1987 by Okutsu many endoscopic techniques have been developed, but the majority of the literature on ECTR has dealt with the Chow and Agee techniques. ECTR is indicated for carpal tunnel syndrome that is not responding to conservative treatment for 6 months. This new technique of ECTR is a single-portal technique using instruments originally designed for endoscopic cubital tunnel release, with no disposable instruments used. It also has the advantage of performing the release with the median nerve protected under direct vision. Ten cases were operated with this technique after performing the procedure on 8 hands of 4 fresh frozen cadavers. There were no neurovascular or tendon injuries with this technique and patients were satisfied with the results.
- Published
- 2012
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22. Utilization of recycled cathode ray tubes glass in cement mortar for X-ray radiation-shielding applications.
- Author
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Ling TC, Poon CS, Lam WS, Chan TP, and Fung KK
- Subjects
- Construction Materials, Electrodes, Glass, Recycling, X-Rays
- Abstract
Recycled glass derived from cathode ray tubes (CRT) glass with a specific gravity of approximately 3.0 g/cm(3) can be potentially suitable to be used as fine aggregate for preparing cement mortars for X-ray radiation-shielding applications. In this work, the effects of using crushed glass derived from crushed CRT funnel glass (both acid washed and unwashed) and crushed ordinary beverage container glass at different replacement levels (0%, 25%, 50%, 75% and 100% by volume) of sand on the mechanical properties (strength and density) and radiation-shielding performance of the cement-sand mortars were studied. The results show that all the prepared mortars had compressive strength values greater than 30 MPa which are suitable for most building applications based on ASTM C 270. The density and shielding performance of the mortar prepared with ordinary crushed (lead-free) glass was similar to the control mortar. However, a significant enhancement of radiation-shielding was achieved when the CRT glasses were used due to the presence of lead in the glass. In addition, the radiation shielding contribution of CRT glasses was more pronounced when the mortar was subject to a higher level of X-ray energy., (Copyright © 2011 Elsevier B.V. All rights reserved.)
- Published
- 2012
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23. Quality assurance and quality control for thermal/optical analysis of aerosol samples for organic and elemental carbon.
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Chow JC, Watson JG, Robles J, Wang X, Chen LW, Trimble DL, Kohl SD, Tropp RJ, and Fung KK
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- Analytic Sample Preparation Methods instrumentation, Analytic Sample Preparation Methods methods, Quality Control, Aerosols analysis, Air Pollutants analysis, Analytic Sample Preparation Methods standards, Carbon analysis
- Abstract
Accurate, precise, and valid organic and elemental carbon (OC and EC, respectively) measurements require more effort than the routine analysis of ambient aerosol and source samples. This paper documents the quality assurance (QA) and quality control (QC) procedures that should be implemented to ensure consistency of OC and EC measurements. Prior to field sampling, the appropriate filter substrate must be selected and tested for sampling effectiveness. Unexposed filters are pre-fired to remove contaminants and acceptance tested. After sampling, filters must be stored in the laboratory in clean, labeled containers under refrigeration (<4 °C) to minimize loss of semi-volatile OC. QA activities include participation in laboratory accreditation programs, external system audits, and interlaboratory comparisons. For thermal/optical carbon analyses, periodic QC tests include calibration of the flame ionization detector with different types of carbon standards, thermogram inspection, replicate analyses, quantification of trace oxygen concentrations (<100 ppmv) in the helium atmosphere, and calibration of the sample temperature sensor. These established QA/QC procedures are applicable to aerosol sampling and analysis for carbon and other chemical components.
- Published
- 2011
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24. ZnO hierarchical structures for efficient quasi-solid dye-sensitized solar cells.
- Author
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Cheng C, Shi Y, Zhu C, Li W, Wang L, Fung KK, and Wang N
- Abstract
We report a direct precipitation method for mass production of ZnO microflowers (MFs) containing hierarchical structures. The ZnO MFs are constructed by interlaced single crystalline and porous nanosheets which are ideal photoanode material for dye-sensitized solar cells (DSCs) because the MFs can largely improve the energy harvesting performance and the efficiency of DSCs. Compared with other forms of nano-sized structures, the novel hierarchical structures show obvious advantages in DSC application because of their large surface area for dye-loading, good light scattering efficiency and excellent electrical transport property. The quasi-solid state DSCs fabricated with the MF hierarchical structures exhibited an efficiency of 4.12%, much higher than that of ZnO nanoparticle-based DSCs, indicating a great potential for the development of highly-efficient quasi-solid DSCs., (This journal is © the Owner Societies 2011)
- Published
- 2011
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25. Immobilization of glucose oxidase on rod-like and vesicle-like mesoporous silica for enhancing current responses of glucose biosensors.
- Author
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Zhou G, Fung KK, Wong LW, Chen Y, Renneberg R, and Yang S
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- Adsorption, Electrodes, Microscopy, Electron, Scanning, Microscopy, Electron, Transmission, Thermodynamics, Biosensing Techniques, Enzymes, Immobilized chemistry, Glucose analysis, Glucose Oxidase chemistry, Silicon Dioxide chemistry
- Abstract
The use of rod-like and vesicle-like mesoporous SiO(2) particles for fabricating high performance glucose biosensors is reported. The distinctively high surface areas of mesoporous structures of SiO(2) rendered the adsorption of glucose oxidase (GOx) feasible. Both morphologies of SiO(2) enhanced the sensitivities of glucose biosensors, but by a factor of 36 for vesicle-like SiO(2) and 18 for rod-like SiO(2), respectively. The greater enhancement of vesicle-like SiO(2) can be accounted for by its higher specific surface area (509 m(2)g(-1)) and larger total pore volume (1.49 cm(3)g(-1)). Interestingly, the current responses of GOx immobilized in interior channels of the mesoporous SiO(2) were enhanced much more than those of simple mixtures of GOx and the mesoporous SiO(2). This suggests that the enhancement of current responses arise not only from the high surface area of SiO(2) for high enzyme loading, but also from the improved enzyme activity upon its adsorption on mesoporous SiO(2). Also compared were the performances of glucose biosensors with GOx immobilized on mesoporous SiO(2) by physical adsorption and by covalent binding to 3-aminopropyltrimethoxysilane (APTMS) modified SiO(2) using glutaraldehyde as the cross-linker. The covalent binding approach resulted in higher enzyme loading but lower current sensitivity than with the physical adsorption., (Copyright © 2011 Elsevier B.V. All rights reserved.)
- Published
- 2011
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26. A randomized trial on addition of concurrent-adjuvant chemotherapy and/or accelerated fractionation for locally-advanced nasopharyngeal carcinoma.
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Lee AW, Tung SY, Chan AT, Chappell R, Fu YT, Lu TX, Tan T, Chua DT, O'Sullivan B, Tung R, Ng WT, Leung TW, Leung SF, Yau S, Zhao C, Tan EH, Au GK, Siu L, Fung KK, and Lau WH
- Subjects
- Adult, Aged, Antineoplastic Combined Chemotherapy Protocols adverse effects, Carcinoma, Chemotherapy, Adjuvant, Cisplatin administration & dosage, Combined Modality Therapy, Female, Fluorouracil administration & dosage, Humans, Male, Middle Aged, Nasopharyngeal Carcinoma, Nasopharyngeal Neoplasms mortality, Nasopharyngeal Neoplasms pathology, Nasopharyngeal Neoplasms therapy, Neoplasm Staging, Patient Compliance, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Dose Fractionation, Radiation
- Abstract
Background and Purpose: To evaluate the therapeutic benefits by adding chemotherapy (+C) and/or accelerated-fractionation (AF) for patients with T3-4N0-1M0 nasopharyngeal carcinoma., Materials and Methods: From 1999 to 2004, 189 eligible patients were randomized to one of four treatment groups (CF/CF+C/AF/AF+C). The number of fractions/week was 5 for the CF groups and 6 for the AF groups. Patients in the +C groups were given concurrent cisplatin plus adjuvant cisplatin and fluorouracil., Results: The AF+C group achieved significantly higher failure-free rate (88% at 5-year) than the CF group (63%; p=0.013), the AF group (56%; p=0.001) and the CF+C group (65%; p=0.027). As compared with CF alone, the increase in late toxicity was statistically insignificant (36% vs. 20%; p=0.25). Deaths due to cancer progression decreased (7% vs. 33%; p=0.011) but deaths due to incidental causes increased (9% vs. 2%; p=0.62). Improvement in overall survival reached borderline significance (85% vs. 66%; p=0.058)., Conclusions: Concurrent-adjuvant chemotherapy combined with AF significantly reduced failure and cancer-specific deaths. Although the increase in major late toxicity and incidental deaths were statistically insignificant, a subtle increase in non-cancer deaths narrowed the overall survival gain., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2011
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27. Vertically aligned ZnO/amorphous-Si core-shell heterostructured nanowire arrays.
- Author
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Cheng C, Wang TL, Feng L, Li W, Ho KM, Loy MM, Fung KK, and Wang N
- Abstract
We report the synthesis of vertically aligned ZnO/a-Si core-shell nanowire arrays (ZnO nanowires coated with amorphous silicon) through chemical vapor deposition. The core-shell heterostructured nanowires possessed uniform morphology and the thickness of the amorphous silicon shells could be controlled easily by tuning the deposition duration and temperature. The core-shell heterostructured nanowires exhibited enhanced antireflection and absorption performance as well as tunable PL properties. Because the individual ZnO/a-Si nanowires showed p-type characteristics and the ZnO cores were n-type semiconductors, the core-shell nanowires formed p-n junctions naturally.
- Published
- 2010
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28. Nanostructural transformation and formation of heterojunctions from Si nanowires.
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Wong TL, Cheng C, Li W, Fung KK, and Wang N
- Subjects
- Calibration, Materials Testing, Microscopy, Electron, Transmission methods, Oxides chemistry, Temperature, Zinc Oxide chemistry, Metal Nanoparticles chemistry, Nanotechnology methods, Nanowires chemistry, Silicon chemistry
- Abstract
Si nanowires coated with Ni showed interesting structural transformation behaviors as observed by in situ transmission electron microscopy. Owing to the presence of the native oxide on Si nanowire surfaces, the Ni thin shells initially segregated into nanosized droplets on the oxide surfaces. The native oxide shells protected the Si cores from reacting with Ni at temperatures below 1350 °C. Ni started the reaction with Si nanowires preferentially at the defects or bending regions of the nanowires. Because the reaction temperature was sufficiently high, the structural transformation was extremely fast and completed within 0.1 s. The resulting nanowires were single crystalline NiSi(2), the most desirable Ni silicide structure for potential applications. Nanowire junctions of NiSi(2)/Si and nanowire-nanotube junctions of NiSi(2)/SiC have been obtained upon further annealing.
- Published
- 2010
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29. The effect of acidification on the determination of elemental carbon, char-, and soot-elemental carbon in soils and sediments.
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Han YM, Cao JJ, Posmentier ES, Chow JC, Watson JG, Fung KK, Jin ZD, Liu SX, and An ZS
- Subjects
- Acids chemistry, Carbon isolation & purification, Hot Temperature, Carbon analysis, Geologic Sediments chemistry, Soil analysis, Soot analysis
- Abstract
We studied the influence of acid pretreatment on the effective distinction between elemental carbon (EC) and organic carbon (OC), and between char-EC and soot-EC. Though widely employed in the pretreatment of soils and sediments for EC quantification, the use of HCl, HF, and HNO(3) could decrease soot thermal stability as acid remains, leading to an underestimation of soot-EC by thermal methods. We compared thermal optical reflectance (TOR) measurements of EC concentrations in char reference materials and in lacustrine and marine sediments following pretreatment with various acids. The results showed that pretreatment with 2M HCl, concentrated HNO(3), 7 M HNO(3), and 1 M HNO(3) did not result in EC oxidation. However, hot concentrated HNO(3) oxidized EC significantly, leading to lower concentrations of EC, char-EC and soot-EC. By comparing the removal of potentially interfering materials, which contain little fire-derived carbon, with different acid pretreatments, we recommend the HCl-HF-HCl and concentrated (not hot) HNO(3)-HF-HCl pretreatments for the determination of EC, char-EC, and soot-EC in soils and sediments using the TOR method.
- Published
- 2009
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30. Development of enzyme-based bar code-style lateral-flow assay for hydrogen peroxide determination.
- Author
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Fung KK, Chan CP, and Renneberg R
- Subjects
- Animals, Antibodies, Anti-Idiotypic chemistry, Blood Glucose, Glucose Oxidase metabolism, Horseradish Peroxidase chemistry, Humans, Reproducibility of Results, Sensitivity and Specificity, Substrate Specificity, Clinical Chemistry Tests methods, Horseradish Peroxidase metabolism, Hydrogen Peroxide analysis
- Abstract
A unique approach of developing a bar code version of lateral-flow enzymatic-based assay for the semi-quantification of hydrogen peroxide is described. The proposed assay system is mainly composed of a goat anti-mouse IgG-horseradish peroxidase conjugate (Gt anti-M IgG-HRP)-coated nitrocellulose (NC) membrane and a peroxidase substrate pad. Unlike the bar code immunochromatographic assay which depends on the stepwise capture of analyte, the principle of enzyme-based bar code lateral-flow assay is based on the different reaction time on successive lines due to the delay in 3,3',5,5'-tetramethylbenzidine (TMB) release. Hydrogen peroxide (H(2)O(2)) acts as a limiting factor which controls the rate of the enzymatic conversion of TMB to blue color complex. The system expresses the concentration of H(2)O(2) in micromole range as three distinct ladder bars in 9 min therefore without the need of any reading device. The major advantages of this assay are its easily readable result, and also its simplicity and low-cost in production offers a cheaper alternative for testing those expensive biosensors might not be available to the third world countries. By incorporating with H(2)O(2)-generating oxidoreductases, the assay can be further extended to detect a variety of analytes with clinical and environmental importance. Glucose was chosen to be the model analyte where the proposed system gave signal response at between 5 microM and 100 microM.
- Published
- 2009
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31. Development of a creatinine enzyme-based bar-code-style lateral-flow assay.
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Fung KK, Chan CP, and Renneberg R
- Subjects
- Adult, Aged, Aged, 80 and over, Antigen-Antibody Complex, Colorimetry, Creatinine blood, Creatinine urine, Female, Horseradish Peroxidase chemistry, Humans, Hydrogen Peroxide chemistry, Kinetics, Male, Middle Aged, Creatinine analysis
- Abstract
A lateral-flow, enzyme-based, bar-code assay for creatinine employing the concept of combination of diffusion and kinetics controlled has been developed. Unlike the traditional bar-code version of immunochromatographic assay, which depends on the stepwise capture of colorimetric tracer-labeled antibody-antigen complex by the immobilized antibody on each successive line, the principle of our proposed assay is based on the delay in TMB release and its diffusion in combination with horseradish peroxidase kinetics. Hydrogen peroxide (H(2)O(2)) produced from enzymatic reactions acts as a limiting factor, which controls the rate of conversion of TMB to blue color complex. The assay takes advantage of giving ladder bar result therefore without the need of any reading device. Depending on the amount of enzymes used, the assay can be one (9 min) or two steps (19 min). The strip assay semiquantitatively measures creatinine concentrations ranging from 0 to 400 microM. Thirty urine samples and thirty serum samples were tested, and the assay showed 90.0% and 86.7% agreement compared with conventional Jaffé method, respectively. This assay provides a tool for quick identification of creatinine for patients without the requirement of any instrument.
- Published
- 2009
- Full Text
- View/download PDF
32. High-quality ZnO nanowire arrays directly fabricated from photoresists.
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Cheng C, Lei M, Feng L, Wong TL, Ho KM, Fung KK, Loy MM, Yu D, and Wang N
- Subjects
- Crystallization, Electrochemistry methods, Gold chemistry, Microscopy, Electron, Scanning, Microscopy, Electron, Transmission, Models, Chemical, Nanoparticles chemistry, Nanotechnology methods, Silicon chemistry, Spectrum Analysis, Raman methods, Metal Nanoparticles chemistry, Nanowires chemistry, Photochemistry methods, Zinc Oxide chemistry
- Abstract
We report a simple and effective method for fabricating and patterning high-quality ZnO nanowire arrays using carbonized photoresists to control the nucleation site, density, and growth direction of the nanowires. The ZnO nanowires fabricated using this method show excellent alignment, crystal quality, and optical properties that are independent of the substrates. The carbonized photoresists provide perfect nucleation sites for the growth of aligned ZnO nanowires and they also perfectly connect to the nanowires to form ideal electrodes that can be used in many applications of ZnO nanomaterials.
- Published
- 2009
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33. The application of thermal methods for determining chemical composition of carbonaceous aerosols: a review.
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Chow JC, Yu JZ, Watson JG, Ho SS, Bohannan TL, Hays MD, and Fung KK
- Subjects
- Aerosols, Environmental Monitoring, Gas Chromatography-Mass Spectrometry, Hot Temperature, Air Pollutants analysis, Carbon analysis, Organic Chemicals analysis
- Abstract
Thermal methods of various forms have been used to quantify carbonaceous materials. Thermal/optical carbon analysis provides measurements of organic and elemental carbon concentrations as well as fractions evolving at specific temperatures in ambient and source aerosols. Detection of thermally desorbed organic compounds with thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS) identifies and quantifies over 100 individual organic compounds in particulate matter (PM) samples. The resulting mass spectra contain information that is consistent among, but different between, source emissions even in the absence of association with specific organic compounds. TD-GC/MS is a demonstrated alternative to solvent extraction for many organic compounds and can be applied to samples from existing networks. It is amenable to field-deployable instruments capable of measuring organic aerosol composition in near real-time. In this review, thermal stability of organic compounds is related to chemical structures, providing a basis for understanding thermochemical properties of carbonaceous aerosols. Recent advances in thermal methods applied to determine aerosol chemical compositions are summarized and their potential for uncovering aerosol chemistry are evaluated. Current limitations and future research needs of the thermal methods are included.
- Published
- 2007
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34. Effects of a self-management arthritis programme with an added exercise component for osteoarthritic knee: randomized controlled trial.
- Author
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Yip YB, Sit JW, Fung KK, Wong DY, Chong SY, Chung LH, and Ng TP
- Subjects
- Activities of Daily Living, Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Osteoarthritis, Knee rehabilitation, Patient Education as Topic, Exercise Therapy methods, Osteoarthritis, Knee therapy, Pain Measurement methods, Self Care methods
- Abstract
Aim: This paper is a report of a study to assess the effect of an adapted arthritis self-management programme with an added focus on exercise practice among osteoarthritic knee sufferers., Background: Osteoarthritis of the knee is a major source of loss of function in older people. Previous studies have found self-management programmes to be effective in increasing arthritis self-efficacy and in mastery of self-management practice., Method: A randomized control trial was carried out from December 2002 to May 2003 and 120 participants (65.9%, including 67 in intervention group and 53 in control group) completed the 16-week postintervention assessments. Outcome measures included arthritis self-efficacy, use of self-management techniques, pain intensity and daily activity., Findings: At 16 weeks, there was a 'statistically' significant improvement in the arthritis self-efficacy level (P
- Published
- 2007
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35. Impact of an Arthritis Self-Management Programme with an added exercise component for osteoarthritic knee sufferers on improving pain, functional outcomes, and use of health care services: An experimental study.
- Author
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Yip YB, Sit JW, Fung KK, Wong DY, Chong SY, Chung LH, and Ng TP
- Subjects
- Activities of Daily Living, Aged, Chi-Square Distribution, Disease Management, Fatigue etiology, Fatigue prevention & control, Female, Health Services statistics & numerical data, Hong Kong, Humans, Male, Middle Aged, Muscle Weakness etiology, Muscle Weakness prevention & control, Osteoarthritis, Knee complications, Osteoarthritis, Knee psychology, Outcome Assessment, Health Care, Pain diagnosis, Pain etiology, Pain prevention & control, Pain Measurement, Program Evaluation, Range of Motion, Articular, Self Care psychology, Surveys and Questionnaires, Exercise Therapy organization & administration, Osteoarthritis, Knee prevention & control, Patient Education as Topic organization & administration, Self Care methods, Self-Help Groups organization & administration
- Abstract
Objective: The aim of this study was to assess the effect of an adopted Arthritis Self-Management Programme (ASMP) with an added exercise component among osteoarthritic knee sufferers in Hong Kong., Methods: An experimental study with 88 participants assigned to an intervention group and 94 participants to a control group. One hundred and forty-nine participants (81.9%) completed the 1 week and 120 participants (65.6%) the 16 week post-intervention assessments. Participants in the intervention group received a 6-week ASMP with an added exercise component. Outcome measures included arthritic pain and fatigue rating, practice of light exercise routines, functional status, and number of unplanned arthritis-related medical consultations. To assess the programme's effect on outcome measures, the between-groups and within-group mean changes were compared using Mann-Whitney U-test and Friedman test., Results: At 16 weeks, there were significant mean changes between groups in four outcome measures: reduction in arthritis pain (p=0.0001) and fatigue (p=0.008), and increased duration of weekly light exercise practice (p=0.0001) and knee flexion (p=0.004). The ability to perform daily activities and the number of unplanned arthritis-related medical consultations show statistically significant improvements between three time-points within the intervention group only (p=0.0001 and p=0.005, respectively), but not between-groups (p=0.14 and p=0.86, respectively). Both groups apparently had no changes in muscle strength., Conclusion: Our findings suggest that the intervention had a positive effect in reducing pain, fatigue, knee range of motion, the practice of exercise routines, the number of medical consultations and in improving functional status and over a 16-week period., Practice Implications: The self-management programme we applied took into account the local context and the ethnicity of the group. This process is worth further exploration and testing in different groups.
- Published
- 2007
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36. Application of high-resolution radiochromic film dosimetry in verifying a small-field stereotactic radiosurgery plan.
- Author
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Lee KY, Fung KK, and Kwok CS
- Subjects
- Dose-Response Relationship, Radiation, Equipment Design, Equipment Failure Analysis, Film Dosimetry methods, Phantoms, Imaging, Radiotherapy Dosage, Reproducibility of Results, Sensitivity and Specificity, Film Dosimetry instrumentation, Radiosurgery instrumentation, Radiosurgery methods, Radiotherapy Planning, Computer-Assisted instrumentation, Radiotherapy Planning, Computer-Assisted methods
- Abstract
A high-resolution radiochromic film dosimetry (Hr-RCFD) method has been applied to verify a small-field stereotactic radiosurgery (SRS) plan. This was done by exposing a RCF in a Perspex head phantom undergoing the same treatment plan as the patient. The dose distribution obtained by the Hr-RCFD was verified against that calculated by the stereotactic treatment planning system and the result was satisfactory. The Hr-RCFD method has been found to be an accurate and practical tool in verifying small-field SRS plans.
- Published
- 2006
- Full Text
- View/download PDF
37. Rapidly progressive necrotising fasciitis following a stonefish sting: a report of two cases.
- Author
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Tang WM, Fung KK, Cheng VC, and Lucke L
- Subjects
- Adult, Animals, Bites and Stings therapy, Fasciitis, Necrotizing microbiology, Fasciitis, Necrotizing therapy, Female, Humans, Male, Middle Aged, Pain Management, Vibrio Infections complications, Bites and Stings complications, Bites and Stings microbiology, Fasciitis, Necrotizing etiology, Fishes, Poisonous, Vibrio vulnificus
- Abstract
Two patients developed rapidly progressive necrotising fasciitis after being stung by a stonefish. Both were given a hot-water bath for pain relief. The hot water may have accelerated bacterial growth and the consequent development of necrotising fasciitis. Vibrio vulnificus was cultured from one patient. It is recommended that patients should receive high dose of oral and intravenous antibiotic prophylaxis for vibrio prevention. Antibiotics should be given before or during, not after, a hot-water bath, and the patient's condition should be monitored closely.
- Published
- 2006
- Full Text
- View/download PDF
38. Dual-peak dose measurement for radiochromic films by a newly developed spectral microdensitometer.
- Author
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Lee KY, Fung KK, and Kwok CS
- Subjects
- Algorithms, Calibration, Dose-Response Relationship, Radiation, Radiotherapy Dosage, Reproducibility of Results, Sensitivity and Specificity, Densitometry instrumentation, Densitometry methods, Film Dosimetry methods, X-Ray Film
- Abstract
Radiochromic film (RCF) dosimetry is usually based on densitometric methods which use an analyzing light source of a fixed or a broad spectrum of wavelengths. These methods have not exploited the sensitivity of the dose response of the RCF otherwise attainable by using a light source with wavelengths peaked at the two absorption peaks in the absorption spectrum of the RCF. A new algorithm of dual-peak dose measurement for the RCF has been proposed in this paper to make use of these dual absorption peaks to achieve the maximum attainable sensitivity. This technique relies on the measurement of the transmittance of the RCF at the wavelength of the major and minor absorption peaks, respectively. The dual-peak dose measurement is accomplished with the aid of a novel spectral microdensitometer developed in our Institute. The microdensitometer utilizes a monochromator to provide a light source of which the wavelength can be matched precisely to the wavelength of the absorption peaks of the RCF. The doses obtained at these wavelengths are fed into a weighted objective function and an optimum dose is searched by minimizing the objective function to give the best estimate of the dose deposited on the film. An initial test shows that there is a good agreement between the estimated and actual dose deposited; and the maximum discrepancy was found to be less than 1%.
- Published
- 2005
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39. TEM study of the structural dependence of the epitaxial passive oxide films on crystal facets in polyhedral nanoparticles of chromium.
- Author
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Rao JC, Zhang XX, Qin B, and Fung KK
- Abstract
Nanocubes and partially truncated rhombic dodecahedral nanoparticles of Cr have been studied by electron diffraction, high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy. It is found that the nanoparticles of Cr are enclosed by the epitaxial passive oxide films. The oxide films on 100% truncated nanocubes of Cr with only one kind of facets, (100) facets, are face-centered cubic (fcc) structured Cr(2)O(3) with a lattice constant of 0.407nm. There are two kinds of oxide films in partially truncated nanoparticles of Cr with two kinds of crystallographic facets, (100) and (110). The same fcc Cr(2)O(3) is found on the (100) facets while the rhombohedral [Formula: see text] -Cr(2)O(3) is found on the (110) facets. This is similar to the two kinds of oxides, fcc and rhombohedral Fe(2)O(3), which have also been observed in polyhedral nanoparticles of Fe. These passive Cr(2)O(3), found in nanoparticles of Cr which have remained unchanged in water for four years, may have important implications for protective oxide films involving Cr.
- Published
- 2004
- Full Text
- View/download PDF
40. Diffuse axonal injury: detection of changes in anisotropy of water diffusion by diffusion-weighted imaging.
- Author
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Chan JH, Tsui EY, Peh WC, Fong D, Fok KF, Leung KM, Yuen MK, and Fung KK
- Subjects
- Adult, Anisotropy, Brain pathology, Female, Humans, Male, Water, Diffuse Axonal Injury diagnosis, Diffusion Magnetic Resonance Imaging
- Abstract
Myelinated axons of white matter demonstrate prominent directional differences in water diffusion. We performed diffusion-weighted imaging on ten patients with head injury to explore the feasibility of using water diffusion anisotropy for quantitating diffuse axonal injury. We showed significant decrease in diffusion anisotropy indices in areas with or without signal abnormality on T2 and T2*-weighted images. We conclude that the water diffusion anisotropy index a potentially useful, sensitive and quantitative way of diagnosing and assessing patients with diffuse axonal injury.
- Published
- 2003
- Full Text
- View/download PDF
41. Necrotising fasciitis of a limb.
- Author
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Tang WM, Ho PL, Fung KK, Yuen KY, and Leong JC
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Child, Child, Preschool, Diagnosis, Differential, Fascia pathology, Fasciitis, Necrotizing pathology, Fasciotomy, Female, Humans, Male, Middle Aged, Reoperation, Risk Factors, Survival Rate, Extremities surgery, Fasciitis, Necrotizing surgery
- Abstract
Between January 1992 and December 1998, we treated 24 patients with necrotising fasciitis of a limb. There were 15 men and nine women with a mean age of 59.8 years (5 to 86). The infection was usually confused with cellulitis. Exquisite pain and early systemic toxicity were the most consistent clinical features. Diabetes mellitus and hepatic cirrhosis were the most commonly associated medical diseases. One third of the patients died. Those with involvement of the limbs above the knee or elbow on admission had a significantly higher rate of mortality than those with distal lesions (Fisher's exact test, p = 0.027). There was no correlation between mortality and advanced age (Student's t-test, p = 0.22) or between amputation and survival (Fisher's exact test, p = 0.39).
- Published
- 2001
- Full Text
- View/download PDF
42. The effect of beam tube potential variation on gonad dose to patients during chest radiography investigated using high sensitivity LiF:Mg,Cu,P thermoluminescent dosemeters.
- Author
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Fung KK and Gilboy WB
- Subjects
- Dose-Response Relationship, Radiation, Female, Humans, Male, Phantoms, Imaging, Radiation Dosage, Sensitivity and Specificity, X-Rays, Gonads radiation effects, Radiography, Thoracic instrumentation, Thermoluminescent Dosimetry instrumentation
- Abstract
Optimization of X-ray beam tube potential (kVp) in radiological examinations can minimize patient dose. This research aims to investigate the effect of tube potential variation on gonad doses to patients during posteroanterior (PA) chest radiography examinations. This study was carried out using a Toshiba general purpose X-ray unit and a Rando phantom. Dose measuring equipment included an ion chamber system, a dose-area product (DAP) meter and a thermoluminescent dosemeter (TLD) reader system with high sensitivity TLD pellets of LiF:Mg,Cu,P for low level gonad dose measurement. PA chest exposures of the phantom to produce a constant exit dose were made using a standard low tube potential (range 60-100 kVp) non-grid technique and a high tube potential (range 95-150 kVp) grid technique. Entrance surface doses (ESDs) and DAPs were also included in the measurements. Effective doses (EDs) were computed from ESD and DAP measurements using NRPB-SR262 and Xdose software. Results show that with the low tube potential technique both ovary dose and testes dose increase with increasing tube potential; statistically significant correlations of r = 0.994 (p = 0.0006) and r = 0.998 (p = 0.001), respectively, were found. For both organs, doses increase at a rate of approximately 2% per kVp. With the high tube potential technique there is insignificant correlation between gonad doses and tube potential. When comparing patient doses from typical exposures made at 70 kVp (low tube potential non-grid technique) with doses from exposures made at 120 kVp (high tube potential grid technique), the high tube potential technique delivers significantly higher values for ESD, and ovary, testes and effective doses by factors of 1.7, 5.2, 5.5 and 2.7, respectively.
- Published
- 2001
- Full Text
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43. "Anode heel effect" on patient dose in lumbar spine radiography.
- Author
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Fung KK and Gilboy WB
- Subjects
- Breast radiation effects, Electrodes, Female, Humans, Lens, Crystalline radiation effects, Male, Ovary radiation effects, Phantoms, Imaging, Posture, Radiography, Testis radiation effects, Thermoluminescent Dosimetry, Thyroid Gland radiation effects, Lumbar Vertebrae diagnostic imaging, Relative Biological Effectiveness
- Abstract
Appropriate use of the "anode heel effect" of the output beam from an X-ray tube can reduce the effective dose to patients in some common radiological examinations. We investigated the variation in radiation intensity across the X-ray beam caused by the anode heel effect, and quantified the difference in absorbed dose to critical organs resulting from lumbar spine X-ray projections carried out with the two possible orientations of the patient along the tube axis (cathode to anode). A Rando phantom and some high sensitivity thermoluminescent dosemeters (TLDs) (LiF:Mg,Cu,P) were used. With the tube axis horizontal, radiation intensity profiles, parallel and perpendicular to the axis, were measured. Lumbar spine radiographs were recorded using the Rando phantom in the standard anteroposterior (AP) and lateral projections. TLD pellets were used to measure the absorbed radiation dose at various sites corresponding to critical organ tissues (ovaries, testes, breasts, thyroid and lens). Each set of projections was recorded in two phantom orientations, first with the phantom head placed towards the cathode end of the X-ray tube, and then in the reverse direction. From the radiation intensity profile of the incident X-ray beam, the "cathode end" to "anode end" air dose ratio was found to be 1.8. In lumbar spine radiography, with the phantom head placed towards the anode end of the X-ray tube, the ovaries and testes received an average dose 17% and 12% higher, respectively, in the lateral projection, and 16% and 27% higher, respectively, in the AP projection, than those obtained in the reverse "patient" orientation. These results indicate that patients (particularly females) should always be positioned with the head placed towards the cathode end of the X-ray tube for lumbar spine radiography to achieve significant dose reductions.
- Published
- 2000
- Full Text
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44. Oxidation behavior of surface-modified titanium for titanium-ceramic restorations.
- Author
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Wang RR and Fung KK
- Subjects
- Analysis of Variance, Chromium chemistry, Dental Bonding, Dental Porcelain chemistry, Diffusion, Electrochemistry, Electron Probe Microanalysis, Electroplating, Hot Temperature, Humans, Materials Testing, Microscopy, Electron, Scanning, Oxidation-Reduction, Oxides chemistry, Porosity, Surface Properties, Ceramics chemistry, Dental Restoration, Permanent, Titanium chemistry
- Abstract
Statement of Problem: Titanium-ceramic bonding is an unsolved problem for the current use of titanium-ceramic restorations., Purpose: The purpose of the study was to characterize oxide formation on titanium surfaces at porcelain sintering temperatures and to determine the effect of chromium coating methods on titanium oxide formation., Material and Methods: Sputter coating and electroplating methods of chromium application were compared and combined., Results: Porous, weak titanium oxide formation on uncoated samples was demonstrated at porcelain sintering temperatures. Groups with chromium coating as an oxygen diffusion barrier exhibited lower oxidation rates, except samples coated by sputtering alone. Temperature effect was found to have the greatest significance on titanium oxidation rate. The overall lowest oxidation rate was located in the group that had chromium coating by the combined coating method and was oxidized at 750 degrees C., Conclusion: The electroplating method requires further investigation and development so that a uniform chromium layer can be deposited on titanium.
- Published
- 1997
- Full Text
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45. Effect of annealing on the giant Hall effect.
- Author
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Jing XN, Wang N, Pakhomov AB, Fung KK, and Yan X
- Published
- 1996
- Full Text
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46. Gingival absorption of triclosan following topical mouthrinse application.
- Author
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Lin YJ, Fung KK, Kong BM, and DeSalva SJ
- Subjects
- Analysis of Variance, Animals, Anti-Infective Agents, Local blood, Anti-Infective Agents, Local urine, Dental Plaque metabolism, Dogs, Female, Male, Time Factors, Triclosan blood, Triclosan urine, Anti-Infective Agents, Local pharmacokinetics, Gingiva metabolism, Mouthwashes pharmacokinetics, Triclosan pharmacokinetics
- Abstract
This study assessed the gingival uptake and urinary excretion of triclosan in dogs following topical applications of a mouthrinse containing 0.03% of triclosan. Five different phases were conducted to define the time course of plasma concentration. The effect of plaque on gingival absorption was also measured. Phase I: Animals' teeth were cleaned of plaque via scraping. Blood sampling time was 0-2 hours. Phase II: Plaque was not removed from the animals' teeth. Blood sampling time was 0-2 hours. Phase III: Plaque was not removed from the animals' teeth. Blood sampling time was 0-6 hours. Phase IV: Plaque was not removed from the animals' teeth. Blood sampling time was 0-12 hours. Phase V: Animals' teeth were cleaned of plaque via scraping. Blood sampling time was 0-12 hours. The test substance was administered to 1 male and 1 female dog in Phases I, II, IV and V, and to 1 male dog in Phase III. The same animals were used in each phase. On the first day of each phase, the animals were treated with distilled water for a 15-minute period. The animals were exposed daily to the test material for a 15-minute period during the remaining 7 days of each phase. The test material was administered using custom-made acrylic applicator trays to enclose the maxillar premolars and molars and gingiva of one-half of the upper jaw. A leak-proof seal along the mucogingival junction and palatal mucosa was established and maintained during the exposure period.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1994
47. Dying for money: overcoming moral hazard in terminal illnesses through compensated physician-assisted death.
- Author
-
Fung KK
- Subjects
- Aged, Altruism, Beneficence, Chronic Disease, Coercion, Delivery of Health Care, Euthanasia, Passive, Freedom, Health Care Rationing, Humans, Medicaid, Medical Futility, Medicare, Morbidity, Personal Autonomy, Physicians, Poverty, Resource Allocation, Right to Die, Terminal Care, Treatment Refusal, United States, Economics, Financial Support, Financing, Government, Insurance, Health, Motivation, Patients, Public Policy, Suicide, Assisted, Terminally Ill
- Published
- 1993
- Full Text
- View/download PDF
48. Wealth transfer through voluntary death.
- Author
-
Fung KK
- Subjects
- Cost Savings methods, Eligibility Determination, Financing, Organized legislation & jurisprudence, Financing, Personal legislation & jurisprudence, Humans, Insurance Benefits economics, Insurance Benefits legislation & jurisprudence, Right to Die legislation & jurisprudence, Suicide, Assisted legislation & jurisprudence, United States, Health Resources economics, Suicide, Assisted economics, Terminal Care economics, Treatment Refusal legislation & jurisprudence
- Abstract
Today, the hopelessly ill who are insured must choose between futile treatment and prolonged morbidity. Legalizing physician-assisted death for the hopelessly ill would broaden patient choice and conserve scarce resources. To ensure that the saved resources will not be re-channeled to more futile treatments for other hopelessly ill patients, those who choose dignified passage should be allowed to determine how the saving from their refusal to a prolonged death is to be re-deployed. Converting projected entitlements into death benefits at a discount would not only reduce health-care and retirements costs but improve allocation of scarce resources.
- Published
- 1993
- Full Text
- View/download PDF
49. Electron-diffraction study of the variation of modulation in Y-doped Bi2Sr2Ca1-xYxCu2O8 single crystals.
- Author
-
Wen JG, Yan YF, and Fung KK
- Published
- 1992
- Full Text
- View/download PDF
50. Discommensurate microstructures in phason-strained octagonal quasicrystal phases of Mo-Cr-Ni.
- Author
-
Jiang JC, Fung KK, and Kuo KH
- Published
- 1992
- Full Text
- View/download PDF
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