Silver-manganese nanocomposite modified screen-printed carbon electrode in the fabrication of an electrochemical, disposable biosensor strip for cystic fibrosis.

A silver-manganese nanocomposite was successfully prepared by the urea hydrolysis method and used to detect chloride ions in sweat electrochemically. The synthesis involves the reaction of manganese sulphate, silver nitrate, and urea at 100 °C for 24 h. The crystalline nature of the particle was studied by diffraction analysis and found to be mixed-phase oxides of manganese alongside the oxides of silver. Morphological studies revealed the presence of quasi-prism-like structures, which is characteristic of ß-MnO2. A disposable sensor was fabricated by screen-printing the catalyst and used for the electrochemical detection of chloride ions in sweat. The sensor exhibited good selectivity, a sensitivity of 22.93 ± 0.64 µA mM-1 cm-2 in solution and 3010 ± 60 µA (log mM) -1 cm-2 for the fabricated sensor strip with a detection range from 5 mM up to 200 mM. The detection limit is 207 ± 7 µM (S/N = 3) in solution and 17 ± 6 µM for the fabricated sensor strip. The relative standard deviation (RSD) of sensor response is 2.38%. A prototype of the biosensor strip was fabricated and validated using real samples. This brings the possibility of developing a real-time biosensor strip for cystic fibrosis in point-of-care testing applications.

Technology-Delivered Psychotherapeutic Interventions in Improving Depressive Symptoms Among People with HIV/AIDS: A Systematic Review and Meta-analysis of Randomised Controlled Trials.

With the increasing popularity of advanced technology, technology-delivered psychotherapeutic interventions (TPIs) may play a promising role in improving depressive symptoms among PLWHA. However, its effectiveness remains unclear. We aimed to synthesise the evidence of the effectiveness of TPIs in improving depressive symptoms of PLWHA using a meta-analytic approach. Seven databases were systematically searched for randomised controlled trials (RCTs) from the inception until August 14, 2018. Random-effects meta-analysis was adopted to assess effect size. Cochran's Q test and I2 were used to investigate the problem of heterogeneity. Sensitivity, subgroup analyses and meta-regression were performed. Of the 43,048 records identified, 14 RCTs were included. The meta-analysis revealed a small effect on reducing depressive symptom scores (d = 0.23, 95% CI - 0.39 to - 0.06) after TPIs. Random-effects meta-regression showed that publication year was a significant moderator (p = 0.013), whereby the latest trials had larger effect size in reducing the depressive symptoms than earlier trials. Our review suggested a possible future approach of utilising TPIs by means of mobile applications and internet-based interventions for PLWHA to reduce their depressive symptoms. This review highlighted the essential key features in designing future TPIs. The overall low-quality evidence suggested the need to conduct further high-quality.

Clinics as spaces of costly disclosure: HIV/STI testing and anticipated stigma among gay, bisexual and queer men.

Gay, bisexual and queer men in Singapore are disproportionately represented in prevalent HIV infections, relative to the general population. While anticipated stigma has been found to be a barrier to HIV/STI testing among gay, bisexual and queer men, little effort has been made to contextualise such stigma within the broader sociocultural milieu. We conducted 35 in-depth interviews with a purposively recruited sample of men in Singapore with a focus on topics such as sexual identity development, formative sexual experiences and HIV/STI testing experience. Interviews were analysed through thematic analysis using techniques borrowed from a grounded theory approach. Participants drew on their past interactions with family, friends, religion, the gay, bisexual and queer men's community and the wider society to construct meanings of deviance in the context of their sexuality. Participants articulated how anticipated stigma was rooted in such deviance, and how clinics or other HIV/STI-related health services served as physical spaces of costly disclosure by exposing or imposing 'deviant' identities on individuals who access these physical spaces, which were otherwise concealed. Findings from the study provide a framework for actions and interventions to address the roots of anticipated stigma in the context of HIV/STI testing among gay, bisexual and queer men.

Soft computing modelling of moisture sorption isotherms of milk-foxtail millet powder and determination of thermodynamic properties.

Moisture sorption isotherms of spray-dried milk-foxtail millet powder were determined at 10, 25 and 40 °C. Sorption data was fitted using classical and soft-computing approaches. The isotherms were of type II, and equilibrium moisture content (EMC) was temperature dependent. The BET monolayer moisture content decreased from 3.30 to 2.67 % as temperature increased from 10 to 40 °C. Amongst the classical models, Ferro-Fontan gave the best fit of EMC-aw data. However, the Sugeno-type adaptive neuro-fuzzy inference system (ANFIS) with generalized bell-shaped membership function performed better than artificial neural network and classical models with RMSE as low as 0.0099. The isosteric heat of sorption decreased from 150.32 kJ mol(-1) at 1 % moisture content to 44.11 kJ mol(-1) at 15 % moisture. The enthalpy-entropy compensation theory was validated, and the isokinetic and harmonic mean temperatures were determined as 333.1 and 297.5 K, respectively.

National HIV programme testing recommendations.

In recognition of the morbidity and mortality associated with human immunodeficiency virus (HIV), the Joint United Nations Programme on HIV/acquired immunodeficiency syndrome (AIDS) (UNAIDS) aims to end the epidemic by setting and striving to achieve the ambitious 95-95-95 targets. However, Singapore is still not performing well in the first UNAIDS target. The National HIV Programme (NHIVP) developed this set of recommendations based on an adaptation of major international guidelines from the World Health Organization and the US Centers for Disease Control and Prevention. The goals of this recommendation are: (1) to increase the uptake of HIV testing; (2) to allow earlier detection and identification of individuals with unrecognised HIV infection; (3) to facilitate linkage to clinical services; and (4) reduce further transmission of HIV infection in Singapore.

Recommendations for the use of antiretroviral therapy in adults living with HIV in Singapore.

Since the advent of combination antiretroviral therapy (ART), the mortality attributable to HIV infection has been reduced by 80%. Newer antiretroviral agents are highly efficacious, have minimal side effects as compared to older drugs, and can be formulated as combination tablets, which reduces patients' pill burden. Despite these advances, 680,000 people died of AIDS-related illnesses worldwide in 2020. The National ART and Monitoring Recommendations by the National HIV Programme are created to guide physicians on the prescribing of ART based on the patients' needs. These recommendations are based on international guidelines and tailored to the local context and unique domestic considerations. It is hoped that with the publication of these recommendations, the care of people living with HIV can be enhanced, bringing us closer to the ending of HIV in our lifetime.

Impact Strength and Dimensional Accuracy of Heat-Cure Denture Base Resin Reinforced With ZrO2 Nanoparticles: An In Vitro Study.

BACKGROUND: Polymerization shrinkage and fracture are the two common trouble shoots with denture base resins. Polymerization shrinkage affects the dimensional accuracy and fit of the prosthesis. The effect of zirconia (ZrO2) nanoparticles on polymerization shrinkage is not documented yet. PURPOSE: The aim and objective of this study were to evaluate the impact strength and dimensional accuracy of heat-cured poly methyl methacrylate (PMMA) on reinforcement with ZrO2 nanoparticles. MATERIALS AND METHODS: Conventional heat-cure denture base resin (control) and the polymer reinforced with 3, 5, and 7 wt% of ZrO2 nanoparticles were prepared and used in this study. Forty bar-shaped specimens were prepared and tested for impact strength using Charpy's type impact tester. Forty denture bases were fabricated and checked for dimensional accuracy by measuring the distance between the denture base and the cast in two different sections using the travelling microscope. RESULTS: The impact strength decreased with increased concentration of ZrO2 and found to be least at 7 wt% concentration (2.01 ± 0.26 J/mm2). The distance between the denture base and the cast significantly decreased both in the posterior palatal seal region (0.060 ± 0.007 cm) and mid-palatine section region (0.057 ± 0.006 cm) with ZrO2 nanoparticles reinforcement and was found to be least at 7 wt% concentration. CONCLUSION: Reinforcement of heat-cured PMMA with ZrO2 nanoparticles significantly increased the dimensional accuracy and decreased the impact strength.

Acceptability of HIV Pre-exposure Prophylaxis (PrEP) and Opinions on PrEP Service Delivery Among Men Who Have Sex With Men in Singapore: A Qualitative Study.

PrEP is effective in preventing HIV transmission among at-risk HIV-negative MSM. A qualitative descriptive study with five focus group discussions (N = 33) involving a purposively recruited sample of Singaporean MSM was conducted from August 2016 to April 2017 to understand local perspectives on potential barriers and motivators to the adoption of PrEP, prior to the implementation of PrEP services in Singapore. Knowledge of PrEP was high, and many viewed PrEP as an attractive alternative to condoms for HIV prevention. Concerns about PrEP included the cost of PrEP and related services, the frequency of PrEP-related clinic visits, fear of side effects, and the stigma associated with using PrEP. Participants felt PrEP was best provided by MSM-friendly providers, and more needed to be done to increase awareness of the effectiveness of PrEP. Access to PrEP for MSM in Singapore has to be affordable, patient-centered, and convenient to maximize the potential benefits of PrEP.

Effect of enzymatic hydrolysis of starch on pasting, rheological and viscoelastic properties of milk-barnyard millet (Echinochloa frumentacea) blends meant for spray drying.

The influence of enzymatic hydrolysis of starch on the pasting properties of barnyard millet was studied using a rheometer. The effects of blending hydrolyzed barnyard millet wort with milk at different ratios (0:1, 1:1, 1:1.5 and 1:2) on flow and viscoelastic behavior were investigated. From the pasting curves, it was evident that enzymatically-hydrolyzed starch did not exhibit typical pasting characteristics expected of normal starch. The Herschel-Bulkley model fitted well to the flow behaviour data, with coefficient of determination (R(2)) ranging from 0.942 to 0.988. All milk-wort blends demonstrated varying degree of shear thinning with flow behavior index (n) ranging from 0.252 to 0.647. Stress-strain data revealed that 1:1 blend of milk to wort had the highest storage modulus (7.09-20.06Pa) and an elastically-dominant behavior (phase angle <45°) over the tested frequency range. The crossover point of G' and G" shifted to higher frequencies with increasing wort content. From the flow and viscoelastic behavior, it was concluded that the 1:1 blend of milk to wort would have least phase separation and better flowability during spray drying.