Alignment of nanostructured tripeptide gels by directional ultrasonication

We demonstrate an in-situ ultrasonic approach to influence self-assembly across the supramolecular to micron length scales, showing enhancement of supramolecular interactions, chirality and orientation, which depends on the peptide sequence and solvent environment. This is the first successful demonstration of using oscillating pressure waves to generate anisotropic organo- and hydro- gels consisting of oriented tripeptides structures

Independent and combined effects of improved water, sanitation, and hygiene, and improved complementary feeding, on child stunting and anaemia in rural Zimbabwe: a cluster-randomised trial.

BACKGROUND: Child stunting reduces survival and impairs neurodevelopment. We tested the independent and combined effects of improved water, sanitation, and hygiene (WASH), and improved infant and young child feeding (IYCF) on stunting and anaemia in in Zimbabwe. METHODS: We did a cluster-randomised, community-based, 2 × 2 factorial trial in two rural districts in Zimbabwe. Clusters were defined as the catchment area of between one and four village health workers employed by the Zimbabwe Ministry of Health and Child Care. Women were eligible for inclusion if they permanently lived in clusters and were confirmed pregnant. Clusters were randomly assigned (1:1:1:1) to standard of care (52 clusters), IYCF (20 g of a small-quantity lipid-based nutrient supplement per day from age 6 to 18 months plus complementary feeding counselling; 53 clusters), WASH (construction of a ventilated improved pit latrine, provision of two handwashing stations, liquid soap, chlorine, and play space plus hygiene counselling; 53 clusters), or IYCF plus WASH (53 clusters). A constrained randomisation technique was used to achieve balance across the groups for 14 variables related to geography, demography, water access, and community-level sanitation coverage. Masking of participants and fieldworkers was not possible. The primary outcomes were infant length-for-age Z score and haemoglobin concentrations at 18 months of age among children born to mothers who were HIV negative during pregnancy. These outcomes were analysed in the intention-to-treat population. We estimated the effects of the interventions by comparing the two IYCF groups with the two non-IYCF groups and the two WASH groups with the two non-WASH groups, except for outcomes that had an important statistical interaction between the interventions. This trial is registered with ClinicalTrials.gov, number NCT01824940. FINDINGS: Between Nov 22, 2012, and March 27, 2015, 5280 pregnant women were enrolled from 211 clusters. 3686 children born to HIV-negative mothers were assessed at age 18 months (884 in the standard of care group from 52 clusters, 893 in the IYCF group from 53 clusters, 918 in the WASH group from 53 clusters, and 991 in the IYCF plus WASH group from 51 clusters). In the IYCF intervention groups, the mean length-for-age Z score was 0·16 (95% CI 0·08-0·23) higher and the mean haemoglobin concentration was 2·03 g/L (1·28-2·79) higher than those in the non-IYCF intervention groups. The IYCF intervention reduced the number of stunted children from 620 (35%) of 1792 to 514 (27%) of 1879, and the number of children with anaemia from 245 (13·9%) of 1759 to 193 (10·5%) of 1845. The WASH intervention had no effect on either primary outcome. Neither intervention reduced the prevalence of diarrhoea at 12 or 18 months. No trial-related serious adverse events, and only three trial-related adverse events, were reported. INTERPRETATION: Household-level elementary WASH interventions implemented in rural areas in low-income countries are unlikely to reduce stunting or anaemia and might not reduce diarrhoea. Implementation of these WASH interventions in combination with IYCF interventions is unlikely to reduce stunting or anaemia more than implementation of IYCF alone. FUNDING: Bill & Melinda Gates Foundation, UK Department for International Development, Wellcome Trust, Swiss Development Cooperation, UNICEF, and US National Institutes of Health.The SHINE trial is funded by the Bill & Melinda Gates Foundation (OPP1021542 and OPP113707); UK Department for International Development; Wellcome Trust, UK (093768/Z/10/Z, 108065/Z/15/Z and 203905/Z/16/Z); Swiss Agency for Development and Cooperation; US National Institutes of Health (2R01HD060338-06); and UNICEF (PCA-2017-0002)

Review of high-power ultrasound-industrial applications and measurement methods

Applications involving high-power ultrasound are expanding rapidly as ultrasonic intensification opportunities are identified in new fields. This is facilitated through new technological developments and an evolution of current systems to tackle challenging problems. It is therefore important to continually update both the scientific and commercial communities on current system performance and limitations. To achieve this objective, this paper addresses two key aspects of high-power ultrasonic systems. In the first part, the review of high-power applications focuses on industrial applications and documents the developing technology from its early cleaning applications through to the advanced sonochemistry, cutting, and water treatment applications used today. The second part provides a comprehensive overview of measurement techniques used in conjunction with high-power ultrasonic systems. This is an important and evolving field which enables design and process engineers to optimize the behaviour and/or operation of key metrics of system performance, such as field distribution or cavitation intensity

Evaluation of ultrasonic reactor for material processing

A novel ultrasonic reactor was designed based on the optimization of acoustic dynamics of its geometry. The reactor relies on 3 frequencies of operation to achieve greater cavitation coverage and greater sonochemical efficiency through more intense bubble collapse. The cavitating region of the vessel is evaluated using a passive acoustic emission hydrophone as well as aluminium foil erosion tests. Results indicate agreement between aluminium foil erosion and broadband acoustic emission from the hydrophone. Erosion results provide validation for multiple frequency reactor design approach in terms of maximizing the cavitating region

Design and evaluation of multi-frequency reactor vessel

This paper looks at the design and evaluation of multi-frequency reactor vesse

Transient supramolecular reconfiguration of peptide nanostructures using ultrasound

Ultrasound, i.e. high frequency oscillating pressure waves, is commonly used to overcome kinetic barriers associated with dissolution, assembly and gelation.We demonstrate that ultrasound energy may also be used to achieve transient reorganization of supramolecular nanostructures, which revert back to the original state when sound is switched off. Aromatic peptide amphiphiles, Fmoc-FL and -YL were used to study the transient acoustic response. These systems showed temporary supramolecular transitions that were sequence dependent. The changes observed were due to an altered balance between H-bonding and p-stacking, giving rise in changes in chiral organisation of peptide building blocks. Transient reconfiguration was visualized by TEM and changes in supramolecular interactions characterized by fluorescence, FT-IR and CD. Remarkably, significant differences are observed when compared to thermal heating, which shows relates to the oscillating and directional characteristics of ultrasound when delivering heat to a system

HIV testing uptake and retention in care of HIV-infected pregnant and breastfeeding women initiated on 'Option B+' in rural Zimbabwe.

OBJECTIVES: Zimbabwe has started to scale up Option B+ for the prevention of mother-to-child transmission of HIV, but there is little published information about uptake or retention in care. This study determined the number and proportion of pregnant and lactating women in rural districts diagnosed with HIV infection and started on Option B+ along with six-month antiretroviral treatment (ART) outcomes. METHODS: This was a retrospective record review of women presenting to antenatal care or maternal and child health services at 34 health facilities in Chikomba and Gutu rural districts, Zimbabwe, between January and March 2014. RESULTS: A total of 2728 women presented to care of whom 2598 were eligible for HIV testing: 76% presented to antenatal care, 20% during labour and delivery and 4% while breastfeeding. Of 2097 (81%) HIV-tested women, 7% were HIV positive. Lower HIV testing uptake was found with increasing parity, late presentation to antenatal care, health centre attendance and in women tested during labour. Ninety-one per cent of the HIV-positive women were started on Option B+. Six-month ART retention in care, including transfers, was 83%. Loss to follow-up was the main cause of attrition. Increasing age and gravida status ≥2 were associated with higher six-month attrition. CONCLUSION: The uptake of HIV testing and Option B+ is high in women attending antenatal and post-natal clinics in rural Zimbabwe, suggesting that the strategy is feasible for national scale-up in the country