Formylation and Bromination of Pyrrolo[2,1-a]isoquinoline Derivatives with Bromoisobutyrate and Dimethyl Sulfoxide.

We have developed an efficient formylation of pyrroloisoquinolines using bromoisobutyrate and dimethyl sulfoxide as carbonyl reagent. Various formylated pyrroloisoquinolines could be prepared in good yields (up to 94%). This formylation process can be easily scaled up to gram scale with good yield. In most cases of pyrroloisoquinolines without methoxy groups, the combination of bromoisobutyrate and dimethyl sulfoxide could act as a bromination reagent, delivering brominated pyrroloisoquinolines in acceptable to good yields (up to 82%).

Investigating the effects of a virtual reality-based stress management programme on inpatients with mental disorders: A pilot randomised controlled trial.

This study aimed to examine the effects and feasibility of a virtual screen-based stress management programme (V-DESSERTS) on inpatients with mental disorders. A single-blinded, pilot randomised controlled trial was conducted in a tertiary hospital in Singapore. Convenience sampling was used and participants were randomised into either the intervention group or the waitlisted control group (WL). The intervention group received individual-based, twice-daily sessions of the programme. Each session comprised education and virtual screen-based relaxation practice. Data were collected through self-reported questionnaires and physiological measures. The intervention group showed a significant increase in perceived relaxation and knowledge in comparison with the WL group. However, inconclusive results were observed on subjective and objective stress. The findings in this study indicated that the V-DESSERTS programme is feasible to be implemented for patients with schizophrenia, depression and bipolar disorders.

How does oil type determine emulsion characteristics in concentrated Na-caseinate emulsions?

Macroscopic properties and ensemble average diffusion of concentrated (dispersed phase 50-60 wt%) Na-caseinate-stabilised emulsions for three different oils (soybean oil, palm olein and tetradecane) were explored. On a volume fraction basis, pulsed gradient stimulated echo (PGSTE)-NMR data show that droplet dynamics for all three systems are similar within a region of the emulsion morphology diagram. The exact limits of the emulsion space depend however on which oil is considered. The reduced solubility of tetradecane in water, and Na-caseinate in tetradecane, result in the stabilisation of flocs during formulation. Floc formation is not observed when soybean oil or palm olein is used under identical emulsion formulation conditions. Linear rheology experiments provide indirect evidence that the local structure and the properties of the thin film interfacial domain of tetradecane emulsions vary from those of soybean oil and palm olein emulsions. Collectively these data indicate that protein/oil interactions within a system dominate over specific oil droplet structure and size distribution, which are similar in the three systems.

Na-caseinate/oil/water systems: emulsion morphology diagrams.

The concentrated (dispersed phase 50-70 wt%) composition space of Na-caseinate, a family of milk proteins, stabilised emulsions was investigated for three different oils: soybean oil, palm olein and tetradecane with pH 6.8 phosphate buffer continuous phase. The variation of emulsion stability and microstructure were explored using static light scattering, diffusion nuclear magnetic resonance, cryo-scanning electron microscopy, rheology and the time varying macroscopic phase separation of the emulsions. For soybean oil and palm olein a rich diversity of emulsion microstructures and stabilities are realised. Five emulsion domains, each having a different microstructure and macroscopic stability have been identified within the composition space probed. For the lowest concentrations of emulsifier bridging flocculation is evident and emulsions are of low stability. Increasing Na-caseinate concentration leads to an increased stability and the existence of distinct individual oil droplets, visualised using cryo-scanning electron microscopy. Further increases in Na-caseinate concentration reduce emulsion stability due to depletion flocculation. Na-caseinate self-assembly is then initiated. At sufficiently high Na-caseinate and/or oil concentrations the continuous phase of the emulsion is a three-dimensional protein network and emulsion stability is again enhanced. At the limits of the emulsion composition space a gel-like paste is formed. The diversity of emulsion microstructure is reduced when tetradecane is the discrete phase. Na-caseinate self-assembly is limited and there is no evidence for formation of a protein network.

The microstructural and rheological properties of Na-caseinate dispersions.

The self-diffusion coefficients of water and casein aggregates in aqueous Na-caseinate dispersions were measured using a pulsed gradient stimulated echo nuclear magnetic resonance technique (PGSTE-NMR). The results for water self-diffusion are discussed in terms of the cell model. The influence of Na-caseinate concentration on water self-diffusion can be explained by obstruction and tortuosity effects arising due to the presence of casein aggregates. Unrestricted diffusion of casein aggregates was measured for all concentrations at short observation times ( approximately 20ms). Despite a near uniform size distribution on increasing Na-caseinate concentration the measured unrestricted diffusion coefficient was a decreasing function of Na-caseinate concentration. Enhanced packing interaction between the aggregates and the slight augmentation of the large tail in the size distribution is the main reason for this observed decrease. On increasing the experimental observation times restricted diffusion of the aggregates is measured. The rheological response of the dispersions was investigated. The stress evolution of the sample with time exhibits three distinct behaviours, irrespective of Na-caseinate concentration and applied shear rate: a spontaneous increase of stress at very short times (<1s), followed by a plateau with fine structure superposed and lastly a sharp increase in stress attributed to irreversible gelation. The latter occurs at significantly reduced times on increasing Na-caseinate concentration. Linear rheology measurements indicate that the dispersions are predominantly locally liquid-like while being macroscopically in a gelled state.