45 research outputs found

    Brief advice and active referral for smoking cessation services among community smokers: a study protocol for randomized controlled trial

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    Abstract Background Most smokers do not use smoking cessation (SC) services although it increases successful quits. Passive referral providing SC information to smokers is commonly used in SC studies. Little was known about active referral in the community setting. This study aims to motivate community smokers to quit by brief SC advice using a validated AWARD model (Ask, Warn, Advise, Refer and Do-it-again) that adjunct with active referral of smokers to various SC services in Hong Kong. Methods/Design This is a single-blinded, parallel three-armed cluster randomized controlled trial (RCT) with two treatment groups of (1) brief SC advice using the AWARD model, active referral to SC services plus a referral card and a health warning leaflet (active referral group) and (2) brief SC advice using AWARD model and health warning leaflet (brief advice group) and a control group receives general very brief advice with a self-help booklet. A total of 1291 smokers will be recruited from 66 clusters (recruitment sessions) with 22 will be allocated to each of the two intervention and one control groups. SC ambassadors will be trained for delivering the interventions and conducting telephone follow-up. The primary outcomes are self-reported 7-days point prevalence (PP) abstinence at 3 and 6 months follow-up. Intention-to-treat principle and multi-level regressions will be used for data analysis. Discussion This is the first RCT on assessing a model combining brief advice and active referral to SC services among community smokers. The results will inform the practices of SC services and intervention studies. Trial registration NCT02539875 (ClinicalTrials.gov registry; registered retrospectively on 22 July 2015

    Breakthrough Curve Performance Using Plate-and-Frame Affinity-Membrane Modules

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    Visual and reversible carbon dioxide sensing enabled by doctor blade coated macroporous photonic crystals

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    With significant impacts of carbon dioxide on global climate change, carbon dioxide sensing is of great importance. However, most of the existing sensing technologies are prone to interferences from carbon monoxide, or suffer from the use of sophisticated instruments. This research reports the development of reproducible carbon dioxide sensor using roll-to-roll compatible doctor blade coated three-dimensional macroporous photonic crystals. The pores are functionalized with amine groups to allow the reaction with carbon dioxide in the presence of humidity. The adsorption of carbon dioxide leads to red-shift and amplitude reduction of the optical stop bands, resulting in carbon dioxide detection with visible readout. The dependences of the diffraction wavelength on carbon dioxide partial pressure for various amine-functionalized photonic crystals and different humidities in the environment are systematically investigated. In addition, the reproducibility of carbon dioxide sensing has also been demonstrated in this research

    Preparation of Porous Polymethyl Methacrylate/Organo-Montmorillonite Composite Membranes for Phenolic Compound Adsorption

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    The preparation of porous poly(methyl methacrylate)/ organo-montmorillonite composite membranes for adsorption application was carried out via entrapment methods. The sponge-like membrane structure was characterized by a scanning electron microscope, whereas the X-ray diffraction, Fourier transform infrared, and thermogravimetric analyses confirmed the incorporation of organo-clays inside the composite membranes. To investigate the applicability of the composite membranes on phenolic compound adsorption, batch-mode adsorption of p-nitrophenol at 0.025 mg/mL was conducted. The optimum feed organo-clay/ polymer ratio was 0.3 for the membrane prepared by the emulsion polymerization method, and in this case 75% of p-nitrophenol was adsorbed after 34 h. 80% methanol was selected as the desorbent for its high ability to desorb p-nitrophenol from the composite membrane. The membrane performance in the flow process was similar to the batch result, and the adsorption/desorption cycle was successfully repeated three times

    Eco-friendly polylactic acid/rice husk ash mixed matrix membrane for efficient purification of lysozyme from chicken egg white

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    An eco-friendly and inexpensive ion-exchange membrane was developed for efficient purification of lysozyme from chicken egg white. Agricultural waste particles (rice husk ash, RHA) were incorporated into biodegradable polymeric matrix (polylatic acid, PLA) to fabricate porous PLA/RHA mixed matrix membrane (MMM) via water-vapour-induced phase inversion. The resulted membrane had an ion-exchange capacity (IEC) of 844 μmol/g membrane. In batch operation at pH 8, the protein adsorption equilibrium was attained within 2 h of contact time and the maximum lysozyme adsorption capacity was 4.49 μmol/g membrane. The adsorptivity of PLA/RHA MMM was essentially contributed from the filled RHA particles. In dynamic operation using one piece of PLA/RHA MMM at 122 L/h/m2 for a feed lysozyme concentration identical to that in mucin-free egg white (0.5 mg/mL), the breakthrough volume was about 50 MMM volume. The lysozyme recovery was 68–70% with a near 100% purity and a purification fold of 35 after an adsorption/washing/elution cycle treating mucin-free egg white mixture. The MMM performance was only deteriorated at a minor percentage during three successive cycles. These results demonstrate that the PLA/RHA MMM process is a green and efficient approach for isolating lysozyme from chicken egg white

    Removal of Benzaldehyde from Methanol Using Alkoxyamine Functionalized Silica Gel

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    Alkoxyamines (RONH2) react readily with aldehydes and ketones to form stable oxime ethers, and, thus are expected to be excellent scavengers of these compounds. We installed alkoxyamines on silica gel surface to remove benzaldehyde from methanol. Silica gel was immersed in H2O2/H2SO4 solution to activate the surface. Activated silica gel was then reacted with 3-chloropropyltrichlorosilane. Displacement of the chloride with N-hydroxyphthalimide and subsequent treatment with hydrazine provided alkoxyamines on the surface of silica gel. The resulting silica gel surface with alkoxyamine functional groups was immersed in a 100 ppm benzaldehyde solution in methanol. After 24 h, the results showed 86.5 + 7.2 % removal of benzaldehyde from methanol

    Sulfonated reduced graphene oxide catalyzed cyclization of hydrazides and carbon dioxide to 1,3,4-oxadiazoles under sonication

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    Acid catalysts facilitate many chemical reactions. Sulfonated reduced grapheneoxide (rGOPhSO3H) has shown to be an encouraging solid acid catalyst because of its efficiency, cost-effectiveness and safety of use. In this study, we prepared the rGOPhSO3H nano acid catalyst, with the introduction of aromatic sulfonic acid radicals onto GO by fractional removal of oxygenated functions. It was thoroughly characterized by FT-IR, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, energy dispersive spectroscopy (EDS) and solid state 13C MAS NMR (SSNMR). Here we report the conversion of CO2 (1.0 atm pressure, at = 50 °C, the source of C1 carbon feed stock) with hydrazides and a catalytic amount rGOPhSO3H, which through a cyclization reaction results in a new strategy for the synthesis of 5-substituted-3H-[1,3,4]-oxadiazol-2-ones (SOxdOs) under ultrasonic irradiation. Hence this concept of cyclization opens up for new insights

    Alicyclic Polyimide/SiO2 Mixed Matrix Membranes for Water/n-Butanol Pervaporation

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    Alicyclic polyimides (PIs) have excellent properties in solubility, mechanical strength, thermal property, etc. This study developed two types of alicyclic PI-based mixed matrix membranes (MMMs) for water/n-butanol pervaporation application, which have never been investigated previously. The fillers were hydrophilic SiO2 nanoparticles. The synthesized PI was mixed with SiO2 nanoparticles in DMAc to make the casting solution, and a liquid film was formed over PET substrate using doctor blade. A dense MMM was fabricated at 80 °C and further treated via multi-stage curing (100–170 °C). The prepared membranes were characterized by FTIR, TGA, FE-SEM, water contact angle, and solvent swelling. The trends of pure solvent swelling effects agree well with the water contact angle results. Moreover, the pervaporation efficiencies of alicyclic PI/SiO2 MMMs for 85 wt% n-butanol aqueous solution at 40 °C were investigated. The results showed that BCDA-3,4′-ODA/SiO2 MMMs had a larger permeation flux and higher separation factor than BCDA-1,3,3-APB/SiO2 MMMs. For both types of MMMs, the separation factor increased first and then decreased, with increasing SiO2 loading. Based on the PSI performance, the optimal SiO2 content was 0.5 wt% for BCDA-3,4′-ODA/SiO2 MMMs and 5 wt% for BCDA-1,3,3-APB/SiO2 MMMs. The overall separation efficiency of BCDA-3,4′-ODA-based membranes was 10–30-fold higher

    Equilibrium adsorption of poly(His)-tagged proteins on immobilized metal affinity chromatographic adsorbents

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    A systematic analysis on the adsorption of homo-oligomeric, poly(His)-tagged recombinant proteins on a hydroxyapatite-based immobilized metal affinity chromatography adsorbent was performed. Under non-denaturing conditions, the Langmuir-Freundlich isotherm model was found ideal for predicting the adsorption behavior of the model proteins. The dissociation constants, as low as 10−9 M, decreased with the number of poly(His) tags, suggesting the presence of multi-point attachment. The maximum adsorption capacities, ranging from 79.1 nmol/g for the 88 kDa epimerase to 42.8 nmol/g for the 320 kDa racemase, were inversely proportional to the contact surface areas of the proteins. Under denaturing conditions, the Langmuir isotherm model fitted well with the experimental data. The maximum adsorption capacities for and the dissociation constants of the three model proteins were essentially identical, as the subunits of the model proteins were of similar dimensions and behaved similarly in the absence of complex tertiary or quaternary structure. Phosphate buffer at a concentration of 500 mM, pH 8.0 was found to be effective for the elution of the model proteins with a recovery yield more than twofold higher than that obtained with 500 mM imidazole. The results suggest the hydroxyapatite-based adsorbent is a promising alternative for large scale applications
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