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1.
Zebrafish ; 21(2): 206-213, 2024 Apr.
Article En | MEDLINE | ID: mdl-38621213

The Ala Wai Canal is an artificial waterway in the tourist district of Waikiki in Honolulu, HI. Originally built to collect runoff from industrial, residential, and green spaces dedicated to recreation, the Ala Wai Canal has since experienced potent levels of toxicity due to this runoff entering the watershed and making it hazardous for both marine life and humans at current concentration, including Danio rerio (zebrafish). A community of learners at educations levels from high school to postbaccalaureate from Oahu, HI was connected through the Consortium for Increasing Research and Collaborative Learning Experiences (CIRCLE) distance research program. This team conducted research with an Investigator and team from Mayo Clinic in Rochester, MN, with the Ala Wai Canal as its primary subject. Through CIRCLE, research trainees sent two 32 oz bottles of Ala Wai- acquired water to a partnered laboratory at the Mayo Clinic in which zebrafish embryos were observed at differing concentrations of the sampled water against a variety of developmental and behavioral assays. Research trainees also created atlases of developmental outcomes in zebrafish following exposure to environmental toxins and tables of potential pesticide contaminants to enable the identification of the substances linked to structural defects and enhanced stress during Ala Wai water exposure experiments.


Water Pollutants, Chemical , Zebrafish , Humans , Animals , Hawaii , Water , Water Pollutants, Chemical/toxicity , Water Pollutants, Chemical/analysis , Embryo, Nonmammalian/chemistry
2.
Comput Methods Programs Biomed ; 248: 108111, 2024 May.
Article En | MEDLINE | ID: mdl-38479147

BACKGROUND AND OBJECTIVE: Training deep learning models for medical image segmentation require large annotated datasets, which can be expensive and time-consuming to create. Active learning is a promising approach to reduce this burden by strategically selecting the most informative samples for segmentation. This study investigates the use of active learning for efficient left ventricle segmentation in echocardiography with sparse expert annotations. METHODS: We adapt and evaluate various sampling techniques, demonstrating their effectiveness in judiciously selecting samples for segmentation. Additionally, we introduce a novel strategy, Optimised Representativeness Sampling, which combines feature-based outliers with the most representative samples to enhance annotation efficiency. RESULTS: Our findings demonstrate a substantial reduction in annotation costs, achieving a remarkable 99% upper bound performance while utilising only 20% of the labelled data. This equates to a reduction of 1680 images needing annotation within our dataset. When applied to a publicly available dataset, our approach yielded a remarkable 70% reduction in required annotation efforts, representing a significant advancement compared to baseline active learning strategies, which achieved only a 50% reduction. Our experiments highlight the nuanced performance of diverse sampling strategies across datasets within the same domain. CONCLUSIONS: The study provides a cost-effective approach to tackle the challenges of limited expert annotations in echocardiography. By introducing a distinct dataset, made publicly available for research purposes, our work contributes to the field's understanding of efficient annotation strategies in medical image segmentation.


Echocardiography , Heart Ventricles , Heart Ventricles/diagnostic imaging , Image Processing, Computer-Assisted
3.
Comput Biol Med ; 171: 108192, 2024 Mar.
Article En | MEDLINE | ID: mdl-38417384

Doppler echocardiography is a widely utilised non-invasive imaging modality for assessing the functionality of heart valves, including the mitral valve. Manual assessments of Doppler traces by clinicians introduce variability, prompting the need for automated solutions. This study introduces an innovative deep learning model for automated detection of peak velocity measurements from mitral inflow Doppler images, independent from Electrocardiogram information. A dataset of Doppler images annotated by multiple expert cardiologists was established, serving as a robust benchmark. The model leverages heatmap regression networks, achieving 96% detection accuracy. The model discrepancy with the expert consensus falls comfortably within the range of inter- and intra-observer variability in measuring Doppler peak velocities. The dataset and models are open-source, fostering further research and clinical application.


Deep Learning , Blood Flow Velocity , Echocardiography, Doppler/methods , Mitral Valve/diagnostic imaging , Ultrasonography, Doppler
4.
J Infect Dis ; 2023 Nov 10.
Article En | MEDLINE | ID: mdl-37950884

BACKGROUND: Annual influenza vaccination is recommended for older adults but repeated vaccination with standard-dose influenza vaccine has been linked to reduced immunogenicity and effectiveness, especially against A(H3N2) viruses. METHODS: Community-dwelling Hong Kong adults aged 65-82 years were randomly allocated to receive 2017/18 standard-dose quadrivalent, MF59-adjuvanted trivalent, high-dose trivalent, and recombinant-HA quadrivalent vaccination. Antibody response to unchanged A(H3N2) vaccine antigen was compared among participants with and without self-reported prior year (2016/17) standard-dose vaccination. RESULTS: Mean fold rise (MFR) in antibody titers from Day 0 to Day 30 by hemagglutination inhibition and virus microneutralization assays were lower among 2017/18 standard-dose and enhanced vaccine recipients with (range, 1.7-3.0) vs. without (range, 4.3-14.3) prior 2016/17 vaccination. MFR was significantly reduced by about one half to four fifths for previously vaccinated recipients of standard-dose and all three enhanced vaccines (ß range, 0.21-0.48). Among prior-year vaccinated older adults, enhanced vaccines induced higher 1.43 to 2.39-fold geometric mean titers and 1.28 to 1.74-fold MFR vs. standard-dose vaccine by microneutralization assay. CONCLUSIONS: In the context of unchanged A(H3N2) vaccine strain, prior-year vaccination was associated with reduced antibody response among both standard-dose and enhanced influenza vaccine recipients. Enhanced vaccines improved antibody response among older adults with prior-year standard-dose vaccination.

5.
Biochem Mol Biol Educ ; 51(2): 180-188, 2023 03.
Article En | MEDLINE | ID: mdl-36606555

A large body of literature has established the benefits of undergraduate research experiences via the traditional apprenticeship model. More recently, several studies have shown that many of these benefits can be recapitulated in course-based undergraduate research experiences (CUREs) that are more scalable and easier for students to participate in, compared to the apprenticeship-based research experiences. Many Biology curricula also incorporate more traditional laboratory courses, where students learn to use common laboratory techniques through guided exercises with known outcomes. Indeed, many programs across the nation provide such programs or courses for students early in their careers, with a view toward increasing student interest and engagement in Biology. While there is general consensus that all lab experiences have some benefits for students, very few studies have examined whether either research experiences or learning biological techniques in more traditional lab courses directly impacts student performance in lecture courses. Here, we show that prior familiarity with laboratory techniques does not improve student performance in a lecture course, even if these techniques are directly related to content being taught in the course. However, having prior research experience improves performance in the course, irrespective of whether the research experience included the use of course-related laboratory techniques.


Curriculum , Learning , Humans , Students , Educational Measurement , Laboratories
6.
Membranes (Basel) ; 12(9)2022 Aug 30.
Article En | MEDLINE | ID: mdl-36135868

CO2/H2 separation using membrane technology is an important research area in order to obtain high purity hydrogen as one source of clean energy. Finding a suitable inorganic membrane is one of the critical issues, which needs to be explored for CO2/H2 separation. In the present study, Ba-SAPO-34 zeolite membrane was synthesized and followed by a modification process. CO2/H2 separation of the membrane was investigated by varying the independent process variables (CO2 % in the feed, pressure difference across the membrane and temperature). Modeling and optimization for the responses (CO2/H2 separation selectivity and CO2 permeance) was performed by applying response surface methodology and central composite design, which is available in Design Expert software. The accuracy of the models in predicting the response was tested by comparing with the experimental value of response and the two values were in good agreement. The optimization of the models gave CO2 permeance of 19.23 × 10-7 mol/m2 s Pa and CO2/H2 separation selectivity of 11.6 at 5% CO2 in the feed, a pressure difference of 100 kPa, and temperature of 30 °C for Ba-SAPO-34 zeolite membrane.

7.
Sci Rep ; 11(1): 22480, 2021 11 18.
Article En | MEDLINE | ID: mdl-34795312

Monitoring community psychological and behavioural responses to coronavirus disease 2019 (COVID-19) is important for informing policy making and risk communication to sustain public compliance with challenging precautionary behaviours and mitigating the psychological impacts. Monthly telephone-based cross-sectional surveys in January-April 2020 and then weekly surveys from May through December 2020 were conducted to monitor changes in public risk perception of COVID-19, personal efficacy in self-protection, confidence in government's ability to control the pandemic, precautionary behaviours, perceived impact of precautionary behaviours, psychological fatigue and distress in Hong Kong, and examine their inter-relationships. While worry about contracting COVID-19 increased, personal efficacy and confidence in government declined as the community incidence of COVID-19 increased. The public maintained high compliance with most precautionary behaviours throughout but relaxed behaviours that were more challenging when disease incidence declined. Public confidence in government was persistently low throughout, of which, a lower level was associated with more psychological fatigue, lower compliance with precautionary behaviours and greater psychological distress. Perceived greater negative impact of precautionary behaviours was also associated with more psychological fatigue which in turn was associated with relaxation of precautionary behaviours. Female, younger and unemployed individuals reported greater psychological distress throughout different stages of the pandemic. Risk communication should focus on promoting confidence in self-protection and pandemic control to avoid helplessness to act when the pandemic resurges. Policy making should prioritize building public trust, enhancing support for sustaining precautionary behaviours, and helping vulnerable groups to adapt to the stress during the pandemic.


Anxiety , COVID-19 , Health Behavior , Pandemics , Psychological Distress , SARS-CoV-2 , Adolescent , Adult , Age Factors , Aged , Anxiety/epidemiology , Anxiety/psychology , COVID-19/epidemiology , COVID-19/psychology , Cross-Sectional Studies , Female , Hong Kong/epidemiology , Humans , Male , Middle Aged , Sex Factors
8.
Membranes (Basel) ; 11(8)2021 Aug 16.
Article En | MEDLINE | ID: mdl-34436392

In recent years, mixed matrix membranes (MMMs) have received worldwide attention for their potential to offer superior gas permeation and separation performance involving CO2 and CH4. However, fabricating defect-free MMMs still remains as a challenge where the incorporation of fillers into MMMs has usually led to some issues including formation of undesirable interfacial voids, which may jeopardize the gas separation performance of the MMMs. This current work investigated the incorporation of zeolite RHO and silane-modified zeolite RHO (NH2-RHO) into polysulfone (PSf) based MMMs with the primary aim of enhancing the membrane's gas permeation and separation performance. The synthesized zeolite RHO, NH2-RHO, and fabricated membranes were characterized by X-ray diffraction (XRD) analysis, Fourier transform infrared-attenuated total reflection (FTIR-ATR), thermogravimetric analysis (TGA) and field emission scanning election microscopy (FESEM). The effects of zeolite loading in the MMMs on the CO2/CH4 separation performance were investigated. By incorporating 1 wt% of zeolite RHO into the MMMs, the CO2 permeability and ideal CO2/CH4 selectivity slightly increased by 4.2% and 2.7%, respectively, compared to that of a pristine PSf membrane. On the other hand, a significant enhancement of 45% in ideal CO2/CH4 selectivity was attained by MMMs incorporated with 2 wt% of zeolite NH2-RHO compared to a pristine PSf membrane. Besides, all MMMs incorporated with zeolite NH2-RHO displayed higher ideal CO2/CH4 selectivity than that of the MMMs incorporated with zeolite RHO. By incorporating 1-3 wt% zeolite NH2-RHO into PSf matrix, MMMs without interfacial voids were successfully fabricated. Consequently, significant enhancement in ideal CO2/CH4 selectivity was enabled by the incorporation of zeolite NH2-RHO into MMMs.

9.
Clin Infect Dis ; 73(12): 2298-2305, 2021 12 16.
Article En | MEDLINE | ID: mdl-33406238

BACKGROUND: Disparities were marked in previous pandemics, usually with higher attack rates reported for those in lower socioeconomic positions and for ethnic minorities. METHODS: We examined characteristics of laboratory-confirmed coronavirus disease 2019 (COVID-19) cases in Hong Kong, assessed associations between incidence and population-level characteristics at the level of small geographic areas, and evaluated relations between socioeconomics and work-from-home (WFH) arrangements. RESULTS: The largest source of COVID-19 importations switched from students studying overseas in the second wave to foreign domestic helpers in the third. The local cases were mostly individuals not in formal employment (retirees and homemakers) and production workers who were unable to WFH. For every 10% increase in the proportion of population employed as executives or professionals in a given geographic region, there was an 84% (95% confidence interval [CI], 1-97%) reduction in the incidence of COVID-19 during the third wave. In contrast, in the first 2 waves, the same was associated with 3.69 times (95% CI, 1.02-13.33) higher incidence. Executives and professionals were more likely to implement WFH and experienced frequent changes in WFH practice compared with production workers. CONCLUSIONS: Consistent findings on the reversed socioeconomic patterning of COVID-19 burden between infection waves in Hong Kong in both individual- and population-level analyses indicated that risks of infections may be related to occupations involving high exposure frequency and WFH flexibility. Contextual determinants should be taken into account in policy planning aiming at mitigating such disparities.


COVID-19 , Ethnic and Racial Minorities , Hong Kong/epidemiology , Humans , Pandemics , SARS-CoV-2
10.
J Infect Dis ; 222(8): 1383-1391, 2020 09 14.
Article En | MEDLINE | ID: mdl-32407535

BACKGROUND: We analyzed data from a randomized controlled trial on the reactogenicity of 3 enhanced influenza vaccines compared with standard-dose (SD) inactivated influenza vaccine. METHODS: We enrolled community-dwelling older adults in Hong Kong, and we randomly allocated them to receive 2017-2018 northern hemisphere formulations of SD vaccine (FluQuadri; Sanofi Pasteur), MF59-adjuvanted vaccine (FLUAD; Seqirus), high-dose (HD) vaccine (Fluzone High-Dose; Sanofi Pasteur), or recombinant hemagglutinin vaccine (Flublok; Sanofi Pasteur). Local and systemic reactions were evaluated at days 1, 3, 7, and 14 after vaccination. RESULTS: Reported reactions were generally mild and short-lived. Systemic reactions occurred in similar proportions of participants by vaccine. Some local reactions were slightly more frequently reported among recipients of the MF59-adjuvanted and HD vaccines than among SD vaccine recipients. Participants reporting feverishness 1 day after vaccination had mean fold rises in postvaccination hemagglutination inhibition titers that were 1.85-fold higher (95% confidence interval, 1.01-3.38) for A(H1N1) than in those who did not report feverishness. CONCLUSIONS: Some acute local reactions were more frequent after vaccination with MF59-adjuvanted and HD influenza vaccines, compared with SD inactivated influenza vaccine, whereas systemic symptoms occurred at similar frequencies in all groups. The association between feverishness and immunogenicity should be further investigated in a larger population. CLINICAL TRIALS REGISTRATION: NCT03330132.


Influenza Vaccines/adverse effects , Influenza Vaccines/immunology , Aged , Aged, 80 and over , Antibodies, Viral/blood , Antibodies, Viral/immunology , Female , Hemagglutination Inhibition Tests , Hong Kong/epidemiology , Humans , Influenza A virus/immunology , Influenza Vaccines/administration & dosage , Influenza, Human/epidemiology , Influenza, Human/prevention & control , Betainfluenzavirus/immunology , Male , Vaccines, Inactivated/administration & dosage , Vaccines, Inactivated/adverse effects , Vaccines, Inactivated/immunology , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/adverse effects , Vaccines, Synthetic/immunology
11.
Vaccine ; 38(29): 4557-4563, 2020 06 15.
Article En | MEDLINE | ID: mdl-32414654

OBJECTIVES: This study examined the relative importance of factors relating to vaccine characteristics, social normative influence and convenience in access to vaccine for determining decision making for seasonal influenza vaccination (SIV) among healthcare personnel (HCP), aiming to optimize existing influenza vaccination programmes for HCP. METHODS: A discrete choice experiment (DCE) was conducted in HCP working in public hospitals in Hong Kong. The DCE was designed to examine the relative importance of vaccine characteristics (vaccine efficacy and safety), social normative influence reflected by the proportion of HCP colleagues intending to take SIV, and convenience in access to vaccine indicated by vaccination programme duration, vaccination location, vaccination arrangement procedure and service hours in determining influenza vaccination choice among HCP. Mixed logit regression modelling was conducted to examine the preference weight (ß) of factors included in the DCE for determining vaccination choice. RESULTS: Vaccination probability increased with increase in vaccine efficacy (ß = 0.02 for per 1% increase), vaccination location changing from "designated staff clinic" to "mobile station" (ß = 0.37), vaccination arrangement procedure changing from "by appointment" to "by walk-in" (ß = 0.99), but decreased with the increase in probability of mild reactions to vaccination (ß = -0.05 for per 1% increase). CONCLUSION: Vaccine safety was judged to be more important than vaccine efficacy for determining vaccination choice. Arranging vaccination service by walk-in and implementing mobile vaccination station should be considered in future SIV programmes to compensate for the effect of perceived low vaccination efficacy and concerns about vaccine safety to promote SIV uptake among HCP.


Influenza Vaccines , Influenza, Human , Health Personnel , Hong Kong , Humans , Influenza, Human/prevention & control , Vaccination
12.
Lancet Public Health ; 5(5): e279-e288, 2020 05.
Article En | MEDLINE | ID: mdl-32311320

BACKGROUND: A range of public health measures have been implemented to suppress local transmission of coronavirus disease 2019 (COVID-19) in Hong Kong. We examined the effect of these interventions and behavioural changes of the public on the incidence of COVID-19, as well as on influenza virus infections, which might share some aspects of transmission dynamics with COVID-19. METHODS: We analysed data on laboratory-confirmed COVID-19 cases, influenza surveillance data in outpatients of all ages, and influenza hospitalisations in children. We estimated the daily effective reproduction number (Rt) for COVID-19 and influenza A H1N1 to estimate changes in transmissibility over time. Attitudes towards COVID-19 and changes in population behaviours were reviewed through three telephone surveys done on Jan 20-23, Feb 11-14, and March 10-13, 2020. FINDINGS: COVID-19 transmissibility measured by Rt has remained at approximately 1 for 8 weeks in Hong Kong. Influenza transmission declined substantially after the implementation of social distancing measures and changes in population behaviours in late January, with a 44% (95% CI 34-53%) reduction in transmissibility in the community, from an estimated Rt of 1·28 (95% CI 1·26-1·30) before the start of the school closures to 0·72 (0·70-0·74) during the closure weeks. Similarly, a 33% (24-43%) reduction in transmissibility was seen based on paediatric hospitalisation rates, from an Rt of 1·10 (1·06-1·12) before the start of the school closures to 0·73 (0·68-0·77) after school closures. Among respondents to the surveys, 74·5%, 97·5%, and 98·8% reported wearing masks when going out, and 61·3%, 90·2%, and 85·1% reported avoiding crowded places in surveys 1 (n=1008), 2 (n=1000), and 3 (n=1005), respectively. INTERPRETATION: Our study shows that non-pharmaceutical interventions (including border restrictions, quarantine and isolation, distancing, and changes in population behaviour) were associated with reduced transmission of COVID-19 in Hong Kong, and are also likely to have substantially reduced influenza transmission in early February, 2020. FUNDING: Health and Medical Research Fund, Hong Kong.


Coronavirus Infections/prevention & control , Influenza A Virus, H1N1 Subtype , Influenza, Human/prevention & control , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Adult , Betacoronavirus/isolation & purification , COVID-19 , Child , Coronavirus Infections/diagnosis , Coronavirus Infections/epidemiology , Cross-Sectional Studies , Health Knowledge, Attitudes, Practice , Hong Kong/epidemiology , Hospitalization/statistics & numerical data , Humans , Incidence , Influenza, Human/epidemiology , Influenza, Human/therapy , Pneumonia, Viral/diagnosis , Pneumonia, Viral/epidemiology , Risk Assessment , SARS-CoV-2
13.
J Infect Dis ; 221(1): 33-41, 2020 01 01.
Article En | MEDLINE | ID: mdl-31282541

BACKGROUND: Immune responses to influenza vaccination can be weaker in older adults than in other age groups. We hypothesized that antibody responses would be particularly weak among repeat vaccinees when the current and prior season vaccine components are the same. METHODS: An observational study was conducted among 827 older adults (aged ≥75 years) in Hong Kong. Serum samples were collected immediately before and 1 month after receipt of the 2015-2016 quadrivalent inactivated influenza vaccine. We measured antibody titers with the hemagglutination inhibition assay and compared the mean fold rise from prevaccination to postvaccination titers and the proportions with postvaccination titers ≥40 or ≥160. RESULTS: Participants who reported receipt of vaccination during either of the previous 2 years had a lower mean fold rise against all strains than with those who did not. Mean fold rises for A(H3N2) and B/Yamagata were particularly weak after repeated vaccination with the same vaccine strain, but we did not generally find significant differences in the proportions of participants with postvaccination titers ≥40 and ≥160. CONCLUSIONS: Overall, we found that reduced antibody responses in repeat vaccinees were particularly reduced among older adults who had received vaccination against the same strains in preceding years.


Antibodies, Viral/blood , Influenza A Virus, H1N1 Subtype/immunology , Influenza A Virus, H3N2 Subtype/immunology , Influenza B virus/immunology , Influenza Vaccines/immunology , Age Factors , Aged , Aged, 80 and over , Female , Hemagglutination , Hong Kong , Humans , Immunization, Secondary , Immunogenicity, Vaccine , Male , Vaccination
14.
Vaccine ; 38(3): 690-698, 2020 01 16.
Article En | MEDLINE | ID: mdl-31668824

BACKGROUND: Although annual seasonal influenza vaccination is recommended for healthcare personnel (HCPs), their vaccination uptake has been suboptimal. This study aimed to examine the psychosocial determinants of influenza vaccination among HCPs in Hong Kong using a longitudinal study design based on behavioral change theories. METHODS: Participants were invited to complete a baseline survey before the 2017/18 influenza vaccination campaign to measure their baseline perceptions and vaccination intention, and followed up for 9 months to measure actual vaccination uptake. The survey used a theoretical framework combining the Health Belief Model and Theory of Planned Behaviour with extended psychosocial factors for predicting HCPs' vaccination uptake. Structural equation modelling was used to test the theoretical model and estimate path coefficients (ß) to infer associations of psychosocial factors with HCPs' influenza vaccination uptake. RESULTS: Of the 845 participants who completed follow-up, 43.0% indicated intending to take vaccination and 30.8% reported actual receipt of the vaccination. The structural equation modeling analysis showed that positive attitude towards influenza vaccination (ß = 0.69), greater perceived susceptibility to influenza virus infection (ß = 0.34), greater anticipated regret for not vaccinating (ß = 0.31), and more cues to action (ß = 0.29) were significantly associated with higher vaccination intention which directly predicted greater vaccination uptake (ß = 0.82). Norms were found to have an indirect association with vaccination intention through the mediation of attitude towards influenza vaccination (ß = 0.63). Self-efficacy was significantly associated with actual receipt of influenza vaccination (ß = 0.13) but not vaccination intention. The structural equation model explained 84.7% and 69.6% of the variance, respectively, in HCPs' intention to receive and actual receipt of influenza vaccination. CONCLUSIONS: Attitude towards influenza vaccination was the strongest predictor of HCPs' intention and actual receipt of influenza vaccination. Social norm approach may be an intervention strategy to shape HCPs' attitude towards influenza vaccination and their subsequent decision-making for influenza vaccination.


Health Personnel/psychology , Immunization Programs/methods , Influenza Vaccines/administration & dosage , Influenza, Human/prevention & control , Intention , Vaccination/methods , Adult , Attitude of Health Personnel , Female , Forecasting , Hong Kong/epidemiology , Humans , Influenza, Human/epidemiology , Influenza, Human/psychology , Longitudinal Studies , Male , Middle Aged , Seasons , Surveys and Questionnaires , Vaccination/psychology , Young Adult
15.
Sci Rep ; 9(1): 15062, 2019 10 21.
Article En | MEDLINE | ID: mdl-31636339

In recent years, there are increasing interest on applying ultrasonic irradiation for the synthesis of zeolite due to its advantages including remarkable shortened synthesis duration. In this project, the potential of ultrasonic irradiation treatment on the synthesis of zeolite RHO was investigated. Ultrasonic irradiation treatment time was varied from 30 to 120 minutes for the synthesis of zeolite RHO. The zeolite RHO solid samples were characterized with X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA) and nitrogen adsorption-desorption analysis. The application of ultrasonic irradiation treatment in this study has accelerated the synthesis of zeolite RHO where the synthesis duration has been significantly shortened to 2 days compared to 8 days required by conventional hydrothermal heating without ultrasonic irradiation treatment. Highly crystalline zeolite RHO crystals in truncated octahedron morphology were successfully formed.

16.
Polymers (Basel) ; 11(11)2019 Oct 23.
Article En | MEDLINE | ID: mdl-31652828

Mixed matrix membranes (MMMs) separation is a promising technology for gas permeation and separation involving carbon dioxide (CO2). However, finding a suitable type of filler for the formation of defect-free MMMs with enhancement in gas permeability remains a challenge. Current study focuses on synthesis of KIT-6 silica and followed by the incorporation of KIT-6 silica as filler into polysulfone (PSF) polymer matrix to fabricate MMMs, with filler loadings of 0-8 wt %. The effect of KIT-6 incorporation on the properties of the fabricated MMMs was evaluated via different characterization techniques. The MMMs were investigated for gas permeability and selectivity with pressure difference of 5 bar at 25 °C. KIT-6 with typical rock-like morphology was synthesized. Incorporation of 2 wt % of KIT-6 into PSF matrix produced MMMs with no void. When KIT-6 loadings in the MMMs were increased from 0 to 2 wt %, the CO2 permeability increased by ~48%, whereas the ideal CO2/CH4 selectivity remained almost constant. However, when the KIT-6 loading in PSF polymer matrix was more than 2 wt %, the formation of voids in the MMMs increased the CO2 permeability but sacrificed the ideal CO2/CH4 selectivity. In current study, KIT-6 was found to be potential filler for PSF matrix under controlled KIT-6 loading for gas permeation.

17.
J Infect Dis ; 219(10): 1525-1535, 2019 04 19.
Article En | MEDLINE | ID: mdl-30551178

BACKGROUND: A number of enhanced influenza vaccines have been developed for use in older adults, including high-dose, MF59-adjuvanted, and intradermal vaccines. METHODS: We conducted a systematic review examining the improvements in antibody responses measured by the hemagglutination inhibition assay associated with these enhanced vaccines, compared with each other and with the standard-dose (SD) vaccine using random effects models. RESULTS: Thirty-nine trials were included. Compared with adults aged ≥60 years receiving SD vaccines, those receiving enhanced vaccines had significantly higher postvaccination titers (for all vaccine strains) and higher proportions with elevated titers ≥40 (for most vaccine strains). High-dose vaccine elicited 82% higher postvaccination titer to A(H3N2) compared with SD vaccine; this was significantly higher than the 52% estimated for MF59-adjuvanted versus SD vaccines (P = .04), which was higher than the 32% estimated for intradermal versus SD vaccines (P < .01). CONCLUSIONS: Overall, by summarizing current evidence, we found that enhanced vaccines had greater antibody responses than the SD vaccine. Indications of differences among enhanced vaccines highlight the fact that further research is needed to compare new vaccine options, especially during seasons with mismatched circulating strains and for immune outcomes other than hemagglutination inhibition titers as well as vaccine efficacy.


Aging/immunology , Immunogenicity, Vaccine , Influenza Vaccines/immunology , Influenza, Human/immunology , Adjuvants, Immunologic/therapeutic use , Aged , Aged, 80 and over , Antibody Formation , Hemagglutination Inhibition Tests , Humans , Influenza A Virus, H1N1 Subtype/immunology , Influenza A Virus, H3N2 Subtype/immunology , Influenza B virus/immunology , Influenza, Human/prevention & control , Injections, Intradermal , Middle Aged
18.
Vaccine ; 36(41): 6117-6123, 2018 10 01.
Article En | MEDLINE | ID: mdl-30190121

BACKGROUND: Influenza vaccination is the most effective intervention to prevent influenza virus infections. Vaccine effectiveness (VE) can vary due to factors such as matching between vaccine strains and prevailing strains, age and other characteristics of the vaccine recipients. OBJECTIVE: To evaluate influenza VE against medically-attended illness in different age groups and against specific influenza types/subtypes in Hong Kong. METHODS: A test-negative study was conducted from December 2014 through August 2017 in 20 outpatient clinics. Patients at least 6 months of age presenting with at least two symptoms of acute respiratory illness, ARI (fever ≥37.8 °C, cough, sore throat, runny nose, headache, myalgia and phlegm) within 72 h of onset were tested for influenza virus by reverse transcription polymerase chain reaction (PCR). Vaccination history was assessed by self-report or medical records at the clinics. VE against medically-attended illness was estimated using conditional logistic regression for influenza PCR result versus vaccination history, matching by calendar time and adjusting for age, age-squared, sex, and chronic medical illness. Additional analyses examined VE by age group and by influenza type/subtype. RESULTS: We enrolled 2566 patients, of whom 1118 (43.6%) tested positive for influenza A or B virus by PCR. Test-positive subjects were generally older, more likely to present with one of the symptoms of ARI, and less likely to receive vaccination against influenza. VE estimates for influenza A(H1N1), A(H3N2), B/Yamagata and B/Victoria were 61.6% (95% confidence interval, CI: 21.8%, 81.1%), 26.4% (95% CI: -1.3%, 46.6%), 67.0% (95% CI: 25.9%, 85.3%), 60.4% (95% CI: 0.3%, 84.3%), respectively. Estimates of VE by age group were generally higher in adults aged 50-64 and lower among children and older adults. CONCLUSIONS: VE against medically-attended influenza was moderate in Hong Kong, confirming the impact of influenza vaccination in reducing disease burden. The reduced VE for influenza A(H3N2) is a continuing concern.


Influenza Vaccines/therapeutic use , Influenza, Human/prevention & control , Female , Hong Kong , Humans , Influenza A Virus, H1N1 Subtype/immunology , Influenza A Virus, H1N1 Subtype/pathogenicity , Influenza A Virus, H3N2 Subtype/immunology , Influenza A Virus, H3N2 Subtype/pathogenicity , Influenza Vaccines/immunology , Influenza, Human/immunology , Male
19.
BMJ Open ; 8(2): e018815, 2018 02 12.
Article En | MEDLINE | ID: mdl-29440212

OBJECTIVE: With an elderly population that is set to more than double by 2050 worldwide, there will be an increased demand for elderly care. This poses several impediments in the delivery of high-quality health and social care. Socially assistive robot (SAR) technology could assume new roles in health and social care to meet this higher demand. This review qualitatively examines the literature on the use of SAR in elderly care and aims to establish the roles this technology may play in the future. DESIGN: Scoping review. DATA SOURCES: Search of CINAHL, Cochrane Library, Embase, MEDLINE, PsychINFO and Scopus databases was conducted, complemented with a free search using Google Scholar and reference harvesting. All publications went through a selection process, which involved sequentially reviewing the title, abstract and full text of the publication. No limitations regarding date of publication were imposed, and only English publications were taken into account. The main search was conducted in March 2016, and the latest search was conducted in September 2017. ELIGIBILITY CRITERIA: The inclusion criteria consist of elderly participants, any elderly healthcare facility, humanoid and pet robots and all social interaction types with the robot. Exclusions were acceptability studies, technical reports of robots and publications surrounding physically or surgically assistive robots. RESULTS: In total, 61 final publications were included in the review, describing 33 studies and including 1574 participants and 11 robots. 28 of the 33 papers report positive findings. Five roles of SAR were identified: affective therapy, cognitive training, social facilitator, companionship and physiological therapy. CONCLUSIONS: Although many positive outcomes were reported, a large proportion of the studies have methodological issues, which limit the utility of the results. Nonetheless, the reported value of SAR in elderly care does warrant further investigation. Future studies should endeavour to validate the roles demonstrated in this review. SYSTEMATIC REVIEW REGISTRATION: NIHR 58672.


Aging/psychology , Interpersonal Relations , Quality of Health Care , Robotics/statistics & numerical data , Aged , Humans , Quality of Life , Randomized Controlled Trials as Topic
20.
Clin Infect Dis ; 66(6): 904-912, 2018 03 05.
Article En | MEDLINE | ID: mdl-29069368

Background: Many health authorities recommend influenza vaccination of older adults to reduce disease burden. We hypothesized that in tropical and subtropical areas with more prolonged influenza seasons, twice-annual influenza vaccination might provide older adults with improved immunity against influenza. Methods: In 2014-2015, Hong Kong experienced a substantial A(H3N2) winter epidemic with a mismatched vaccine. Local authorities procured and administered to older adults the 2015 southern hemisphere influenza vaccine, which included an updated and matching A/Switzerland/9715293/2013(H3N2) strain. We compared immune parameters in pre- and postvaccination sera from older adults ≥75 years of age who received 1 vs 2 influenza vaccines per year. Results: We enrolled 978 older adults with 470 vaccinations for summer 2015 and 827 vaccinations for winter 2015-2016. Recipients of southern hemisphere vaccination had higher geometric mean titers (GMTs) by the hemagglutination inhibition assay against all 3 vaccine strains. When receiving influenza vaccination for the subsequent winter, the southern hemisphere vaccine recipients had higher prevaccination GMTs but lower postvaccination GMTs, compared to those who had not received the southern hemisphere vaccine. Furthermore, cellular immunity was impacted by biannual vaccination, with reduced influenza-specific CD4 T-cell responses in the second season of vaccination. Conclusions: We observed some reductions in immune responses in the twice-annual vaccination group compared with the once-annual vaccination group, in the context of unchanging vaccine strains, while protection was likely to have been improved during the summer and autumn for the twice-annual vaccination group due to the continued circulation of the A/Switzerland/9715293/2013(H3N2) virus.


Antibodies, Viral/blood , Immunization Schedule , Influenza Vaccines/immunology , Influenza, Human/prevention & control , Aged , Aged, 80 and over , CD4-Positive T-Lymphocytes/immunology , Female , Hong Kong/epidemiology , Humans , Immunity, Cellular , Influenza A Virus, H3N2 Subtype/immunology , Influenza B virus/immunology , Influenza Vaccines/administration & dosage , Influenza, Human/immunology , Male , Seasons
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