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BACKGROUND: Adults with schizophrenia experience a range of neurocognitive problems that affect their daily functioning. Evidence for the efficacy of cognitive remediation in schizophrenia has been established, but its implementation in under-resourced community-based settings is less well-studied. In recent years, interventions have also focused on the strategy-learning approach in favor of drill-and-practice. Moreover, there is an increasing recognition to address social cognition and negative symptoms alongside neurocognition. This study attempts to carry out cognitive remediation in a community mental health setting. The Neuropsychological and Educational Approach to Remediation (NEAR) is used as the cognitive remediation intervention. Neurocognitive and social cognitive games will be introduced during the computer-assisted cognitive exercises sessions. In addition, the instructional technique will foster the use of metacognition and cognitive strategies. Moreover, metamotivation training will be the focus of some bridging sessions to enhance motivation to engage in goal-directed learning behaviors. The aims of the study are to 1) investigate the effects of cognitive remediation on neurocognition, social cognition and functional outcomes of participants with schizophrenia/schizoaffective disorders in community mental health settings; and 2) explore the mediators for change (eg: metamotivation, metacognition and negative symptoms) in cognitive performance and functional outcomes. METHODS: This randomized controlled trial will be conducted in three Singapore Anglican Community Services (SACS) centers, where standard psychiatric rehabilitation is delivered. Participants who are randomized to the experimental arm will receive cognitive remediation and psychiatric rehabilitation, while those randomized to the control arm will receive standard psychiatric rehabilitation only. Cognitive remediation is carried out three times a week for 12 weeks. It consists of computer-assisted cognitive exercises, as well as bridging groups to aid transfer of learning to daily living. Baseline, post-intervention and eight-week follow-up measurements will be collected. Group by time differences in cognitive performance, negative symptoms, metamotivation, metacognition, functioning and recovery will be analyzed across the three time points. Mediators for improvement in cognitive performance and functioning will also be explored. DISCUSSION: Findings of this research will add to the body of knowledge about the key therapeutic ingredients within a strategy-based cognitive remediation program and improve its implementation within under-resourced community settings. TRIAL REGISTRATION: This study has been registered with ClinicalTrials.gov (ID: NCT06286202). Date of registration: 29 February 2024. Date of last update: 21 May 2024.

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Plant fibers have been studied as sources of nanocellulose due to their sustainable features. This study investigated the effects of acid hydrolysis parameters, reaction temperature, and acid concentration on nanocellulose yield from maguey (Agave cantala) fiber. Nanocellulose was produced from the fibers via the removal of non-cellulosic components through alkali treatment and bleaching, followed by strong acid hydrolysis for 45 min using sulfuric acid (H2SO4). The temperature during acid hydrolysis was 30, 40, 50, and 60 °C, and the H2SO4 concentration was 40, 50, and 60 wt. % H2SO4. Results showed that 53.56% of raw maguey fibers were isolated as cellulose, that is, 89.45% was α-cellulose. The highest nanocellulose yield of 81.58 ± 0.36% was achieved from acid hydrolysis at 50 °C using 50 wt. % H2SO4, producing nanocellulose measuring 8-75 nm in diameter and 72-866 nm in length, as confirmed via field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) analysis. Fourier-transform infrared spectroscopy (FTIR) analysis indicated the chemical transformation of fibers throughout the nanocellulose production process. The zeta potential analysis showed that the nanocellulose had excellent colloidal stability with a highly negative surface charge of -37.3 mV. Meanwhile, X-ray diffraction (XRD) analysis validated the crystallinity of nanocellulose with a crystallinity index of 74.80%. Lastly, thermogravimetric analysis (TGA) demonstrated that the inflection point attributed to the cellulose degradation of the produced nanocellulose is 311.41 °C.

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An easy and environment-friendly route for antibacterial coating suited for mobile phone glass protectors was successfully demonstrated. In this route, freshly prepared chitosan solution in 1% v/v acetic acid was added with 0.1 M silver nitrate solution and 0.1 M sodium hydroxide solution and incubated with agitation at 70 °C to form chitosan-silver nanoparticles (ChAgNPs). Varied concentrations of chitosan solution (i.e., 0.1, 0.2, 0.4, 0.6, and 0.8% w/v) were used to investigate its particle size, size distribution, and later on, its antibacterial activity. Transmission electron microscope (TEM) imaging revealed that the smallest average diameter of silver nanoparticles (AgNPs) was 13.04 nm from 0.8% w/v chitosan solution. Further characterizations of the optimal nanocomposite formulation using UV-vis spectroscopy and Fourier transfer infrared spectroscopy were also performed. Using a dynamic light scattering zetasizer, the average ζ-potential of the optimal ChAgNP formulation was at +56.07 mV, showing high aggregative stability and an average ChAgNP size of 182.37 nm. The ChAgNP nanocoating on glass protectors shows antibacterial activity against Escherichia coli (E. coli) at 24 and 48 h of contact. However, the antibacterial activity decreased from 49.80% (24 h) to 32.60% (48 h).

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Thermally localized solar-driven water evaporation (SWE) in recent years has increasingly been developed due to the potential of cost-efficient freshwater production from small-scale portable devices. In particular, the multistage SWE has attracted much attention as the systems possess mostly a simple foundational structure and high solar-to-thermal conversion output rates, enough to produce freshwater from 1.5 L m-2h-1 (LMH) to 6 LMH. In this study, the currently designed multistage SWE devices were reviewed and examined based on their unique characteristics as well as their performances in freshwater production. The main distinguishing factors in these systems were the condenser staging design and the spectrally selective absorbers either in a form of high solar absorbing material, photovoltaic (PV) cells for water and electricity co-production, and coupling of absorber and solar concentrator. Other elements of the devices involved differences such as the direction of water flow, the number of layers constructed, and the materials used for each layer of the system. The key factors to consider for these systems include the heat and mass transport in the device, solar-to-vapor conversion efficiency, gain output ratio (representing how many times the latent heat has been reused), water production rate/number of stages, and kWh/number of stages. It was evident that most of the studied devices involved slightly different mechanisms and material compositions to draw out higher efficiency rates from the current limitations. The reviewed designs showed the ability to be adopted into small-scale solar desalination allowing for accessibility of sufficient freshwater in needing regions.

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An essential prerequisite for successful solution blow spinning (SBS) is the presence of effective molecular entanglements of polymers in the solution. However, the fabrication of biopolymer fibers is not as straightforward as synthetic polymers. Particularly for biopolymers such as pectin, molecular entanglements are essential but insufficient for successful spinning through the SBS production method. Such a challenge is due to the biopolymer's complex nature. However, incorporating an easily spinnable polymer precursor, such as polyacrylonitrile (PAN), to pectin effectively enabled the production of fibers from the SBS process. In this process, PAN-assisted pectin nanofibers are produced with average diameters ranging from 410.75 ± 3.73 to 477.09 ± 6.60 nm using a feed flow rate of 5 ml h-1, air pressure of 3 bars, syringe tip to collector distance at 30 cm, and spinning time of 10 min. PAN in DMSO solvent at different volume ratios (i.e. 35%-55% v/v) was critical in assisting pectin to produce nanofibers. The addition of a high molecular weight polymer, PAN, to pectin also improved the viscoelasticity of the solution, eventually contributing to its successful SBS process. Furthermore, the composite SBS-spun fibers obtained suggest that its formation is concentration-dependent.

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Cellulose-based nanofiber membrane fabrication remains a global challenge, especially the use of alternative and sustainable sources of cellulosic materials. Herein, an easy and highly scalable cellulose-based nanofiber membrane was successfully fabricated using a solution blow spinning (SBS) method. Such membrane fabrication was carried out with the assistance of an easy-to-spin precursor polymer (i.e. polyacrylonitrile (PAN)). Through this strategy, cellulose acetate (CA) was successfully spun into a ready-to-use membrane. The formation of CA with the PAN nanofiber is concentration-dependent and requires high air pressure to effectively overcome the composite precursor's surface tension and eventually produce nanofibers. Favourable CA concentration in PAN (i.e. 50%-65% v/v CAN/PAN) is important to the formation of sufficient molecular entanglement with PAN in solution. Upon fulfilling the optimized CA concentration, high air pressure (i.e. ≥3 bars) is used to produce jet-like polymeric fibers of PAN dragging off CA, forming numerous nanofibers which are then collected into a substrate forming a membrane. Characterizations of the CA/PAN composite nanofiber were carried out using scanning electron microscopy, Fourier transform infrared, thermogravimetric analysis and differential scanning calorimetry (DSC). Such unique composite nanofiber membranes have potential as filters and adsorbent membranes for air and water/wastewater applications, as well as for biorefinery applications.

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BACKGROUND: The Pint of Science festival is the biggest annual international science festival. In May 2017, we coordinated the first Pint of Science festival in Thailand and reported our initial reflections. Building on this work, we set out to evaluate more systematically events conducted in 2018. METHODS: In 2018, we conducted Pint of Science events at four different locations in Bangkok. Overall, there were 18 talks held over six event-days in 2018. We administered 180 self-reported questionnaires as well as conducted 11 semi-structured interviews and a focus group discussion with audience members and speakers. RESULTS: Of the 180 questionnaires handed out, 125 attendees completed the questionnaire. The majority of attendees came because they were interested in science (68.0%), to learn something new (46.4%) and to enjoy themselves (44.8%). Our qualitative results confirm the quantitative findings. In addition, speakers viewed that they benefited by improving their communication skills and having the opportunity to network with scientists and non-scientists. Speakers also mentioned that such events were a good means to engage with the public, can improve the visibility of their work and potentially attract more funding. To improve the Pint of Science activities, audience members suggested to include a more diverse range of topics, more collaborations with other local research institutions and to hold the event at larger venues. CONCLUSIONS: We conclude that Pint of Science was well received in Bangkok with recommendations to improve minor issues related to practicalities and logistics.

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In this study, synthesis of well-defined carboxymethyl cellulose (CMC) nanowhiskers through a low-pressure solution blow spinning is achieved for the first time. A mixture of methanol, water, and CMC was sprayed through a locally available spray gun at 4 bars, and the collected sample was dried for two hours at 80 °C. Scanning electron microscopy and Fourier transform infrared spectroscopy characterized the samples. The results showed the successful production of many, uniform and well-defined nanowhiskers. The possible series of mechanisms is also discussed. The primary objective of this study is to give insights of a simple and straightforward method that has potential to mass-produce high-quality nanowhiskers in a quick, cheap, and practical manner.

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Herein we report a simple and green synthesis of smart Au and Ag@Au nanocomposite particles using poly(N-isopropylacrylamide)/polyethyleneimine (PNIPAm/PEI) core-shell microgels as dual reductant and templates in an aqueous system. The nanocomposite particles were synthesized through a spontaneous reduction of tetrachloroauric (III) acid to gold nanoparticles at room temperature, and in situ encapsulation and stabilization of the resultant gold nanoparticles (AuNPs) with amine-rich PEI shells. The preformed gold nanoparticles then acted as seed nanoparticles for further generation of Ag@Au bimetallic nanoparticles within the microgel templates at 60 °C. These nanocomposite particles were characterized by TEM, AFM, XPS, UV-vis spectroscopy, zeta-potential, and particle size analysis. The synergistic effects of the smart nanocomposite particles were studied via the reduction of p-nitrophenol to p-aminophenol. The catalytic performance of the bimetallic Ag@Au nanocomposite particles was 25-fold higher than that of the monometallic Au nanoparticles. Finally, the controllable catalytic activities of the Au@PNIPAm/PEI nanocomposite particles were demonstrated via tuning the solution pH and temperature.

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This data article describes the synthesis of temperature-sensitive and amine-rich microgel particle as a dual reductant and template to generate smart gold/polymer nanocomposite particle. TEM images illustrate the influence of reaction temperature on the formation and in-site encapsulation of gold nanoparticles using the temperature-sensitive microgel template. Thermal stability of the resultant gold/polymer composite particles was also examined.