Structural flax/PLA biocomposites: understanding of their thermo-mechanical behaviour.

The extended use of bio-composites for the manufacturing of vehicle components would largely benefit the industry. However, the properties of biocomposites, their mechanical performance under different environments and the effect of different loading conditions are still unclear. Systematic studies have been conducted on flax/PLA biocomposites, to determine the phenomena dominating their mechanical behaviour and their potential use in structural automotive applications

A guideline for the formation of sub-national climate-smart agriculture alliances in Tanzania

About the guideline: This document summarizes recommendations on best practices on how to form and operationalize of sustainable sub-national Climate Smart Agriculture (CSA) alliances for CSA actors in Tanzania. These are based on the experience and recommendations of existing District CSA Alliances and views from selected CSA actors in the country. It seeks to support ongoing efforts in the country to promote the adoption of CSA practices and technologies

Tannin-based flax fibre reinforced composites for structural applications in vehicles.

Innovation is often driven by changes in government policies regulating the industries, especially true in case of the automotive. Except weight savings, the strict EU regulation of 95% recyclable material-made vehicles drives the manufactures and scientists to seek new 'green materials' for structural applications. With handing at two major drawbacks (production cost and safety), ECHOSHELL is supported by EU to develop and optimise structural solutions for superlight electric vehicles by using bio-composites made of high-performance natural fibres and resins, providing enhanced strength and bio-degradability characteristics. Flax reinforced tannin-based composite is selected as one of the candidates and were firstly investigated with different fabric lay-up angles (non-woven flax mat, UD, [0, 90°]4 and [0, +45°, 90°, −45°]2) through authors' work. Some of the obtained results, such as tensile properties and SEM micrographs were shown in this conference paper. The UD flax reinforced composite exhibits the best tensile performance, with tensile strength and modulus of 150 MPa and 9.6 MPa, respectively. It was observed that during tension the oriented-fabric composites showed some delamination process, which are expected to be eliminated through surface treatment (alkali treatment etc.) and nanotechnology, such as the use of nano-fibrils. Failure mechanism of the tested samples were identified through SEM results, indicating that the combination of fibre pull-out, fibre breakage and brittle resins failure mainly contribute to the fracture failure of composites

Effect of fibre configurations on mechanical properties of flax/tannin composites.

Flax reinforced tannin-based composites have a potential to be used in vehicle applications due to the environmental advantages and good mechanical properties. In this paper, the effects of fibre configuration on mechanical properties of flax/tannin composites were investigated for nonwoven and woven fabric lay-up angles (UD, [0°, 90°]2 and [0°, +45°, 90°, -45°]2). The tannin/flax composites were prepared by compression moulding. The manufactured specimens were then characterized for quasi-static tensile properties, dynamic mechanical properties and low-energy impact performance. Failure mechanism was further investigated using microscopy and demonstrated the need for further adhesion improvements. The study shows that the UD fabric reinforced composite performs better in tensile strength and modulus whereas [0°, +45°, 90°, -45°]2 composite provides the best impact energy absorption performance

Factors influencing time to diagnosis and treatment among pediatric oncology patients in Kenya

Early diagnosis and start of treatment are fundamental goals in cancer care. This study determines the time lag and the factors that influence the time to diagnosis and start of treatment. Study participants were parents of childhood cancer patients diagnosed between August 2013 and July 2014 in a hospital in Kenya. Patient, physician, diagnosis, treatment, health care system, and total delay were explored using a questionnaire. Demographic and medical data were collected from the patients' medical records. Parents of 99 childhood cancer patients were interviewed (response rate: 80%). Median total delay was 102 (9–1021) days. Median patient delay (4 days) was significantly shorter than health care system delay (median 87 days; P < .001). Diagnosis delay (median 94 days) was significantly longer than treatment delay (median 6 days; P < .001). days. Lack of health insurance at diagnosis and use of alternative medicine before attending conventional health services were associated with a significantly longer patient delay (P = .041 and P = .017, respectively). The type of cancer had a significant effect on treatment delay (P = .020). The type of health facility attended affected only patient delay (P = .03). Gender, age at diagnosis, stage of disease, parents' education level or income, and distance from hospital did not have a significant effect on the length of any type of delay. Training on childhood cancer should be included in the curricula for medical training institutes. In-service workshops should be held for the health workers already working. Families must be obligated to get health insurance. Families should be encourage to attend conventional health facilities and informed on symptoms of cancer through mass media

Gendered Technology Adoption and Household Food Security in Semi-Arid Eastern Kenya

Hunger and malnutrition are scientific and moral problems that lie at the root of most other global development challenges, since malnutrition effectively blocks development and achievement across generations (Kavishe 1995). In Kenya, agriculture is the cornerstone of the economy. It employs millions, feeds more, and has a multiplier effect in that farming supplies raw materials to, and supports, many other industries. Small-scale farming (on plots averaging 0.2–0.3 hectares) dominates food production in Kenya, pointing to the importance of directing research and development efforts towards smallholder and subsistence farming systems (Hickey et al. 2012). Because most agricultural production takes place at the household level, gender relations are central to understanding both how the farming system works and the extent to which initiatives to build resilience in the farming system (e.g., in relation to project research activities) support equity and improve food and nutrition security. Men and women in various types of households may make separate and autonomous decisions, as well as joint decisions, on important matters such as adoption of new agricultural technologies and practices. These decisions have implications for who provides the labour and who reaps what rewards of that adoption. For example, it has been shown that when women control income, they generally allocate a higher percentage to food, health, clothing, and education for their children than men do (FAO n.d.). As a result, a better understanding of the gendered division of household labour is an essential component of enabling household food provisioning and the marketing of agricultural products through agricultural innovation systems capable of supporting resilience..

Editorial: Improving the delivery of pre-exposure prophylaxis (PrEP) to eliminate vertical HIV transmission

HIV pre-exposure prophylaxis (PrEP) significantly reduces new HIV infections. Among pregnant and lactating cisgender women in high HIV prevalence settings PrEP offers dual benefits for maternal and infant HIV prevention and is increasingly integral to vertical transmission prevention programs. Many countries in East and Southern Africa with high HIV burden have integrated oral PrEP into HIV prevention programs, in the form of daily oral tenofovir disoproxil fumarate (TDF) containing regimens. While daily oral TDF-based PrEP use in pregnancy and lactation is considered safe and effective, only recently are data on PrEP implementation and extended safety emerging. As additional PrEP options become available, there is a need for more evidence on how to ensure effective antenatal and postnatal use

Recycling graphene from supercapacitor electrodes as reinforcing filler for epoxy resins

A wet shredding process has been developed for recycling graphene from the electrodes of supercapacitors into polymer composites. At first, supercapacitors are cut open to expose the interior graphene based electrodes. The electrodes are heat-treated at 200o C to remove the contained solvent, and the heat treatment temperature can be further increased to remove the polymer binder, which binds the graphene on an aluminium foil current collector. After heat treatment, the electrodes are shredded in an epoxy resin to strip off the graphene and the graphene was subsequently dispersed using a high shear mixer. The dispersed graphene is used directly as reinforcing filler for the epoxy resin. A content of 0.40% (wt) of the recycled graphene resulted in a significant increase in both the tensile strength and elongation at break of the epoxy resin. Removal of the binder increases the reinforcing effect of the recycled graphene. However, a compromise can be made to leave the binder in the recycled graphene in order to avoid secondary pollution

Determinants of antibody persistence across doses and continents after single-dose rVSV-ZEBOV vaccination for Ebola virus disease: an observational cohort study.

BACKGROUND: The recombinant vesicular stomatitis virus (rVSV) vaccine expressing the Zaire Ebola virus (ZEBOV) glycoprotein is efficacious in the weeks following single-dose injection, but duration of immunity is unknown. We aimed to assess antibody persistence at 1 and 2 years in volunteers who received single-dose rVSV-ZEBOV in three previous trials. METHODS: In this observational cohort study, we prospectively followed-up participants from the African and European phase 1 rVSV-ZEBOV trials, who were vaccinated once in 2014-15 with 300 000 (low dose) or 10-50 million (high dose) plaque-forming units (pfu) of rVSV-ZEBOV vaccine to assess ZEBOV glycoprotein (IgG) antibody persistence. The primary outcome was ZEBOV glycoprotein-specific IgG geometric mean concentrations (GMCs) measured yearly by ELISA compared with 1 month (ie, 28 days) after immunisation. We report GMCs up to 2 years (Geneva, Switzerland, including neutralising antibodies up to 6 months) and 1 year (Lambaréné, Gabon; Kilifi, Kenya) after vaccination and factors associated with higher antibody persistence beyond 6 months, according to multivariable analyses. Trials and the observational study were registered at ClinicalTrials.gov (Geneva: NCT02287480 and NCT02933931; Kilifi: NCT02296983) and the Pan-African Clinical Trials Registry (Lambaréné PACTR201411000919191). FINDINGS: Of 217 vaccinees from the original studies (102 from the Geneva study, 75 from the Lambaréné study, and 40 from the Kilifi study), 197 returned and provided samples at 1 year (95 from the Geneva study, 63 from the Lambaréné, and 39 from the Kilifi study) and 90 at 2 years (all from the Geneva study). In the Geneva group, 44 (100%) of 44 participants who had been given a high dose (ie, 10-50 million pfu) of vaccine and who were seropositive at day 28 remained seropositive at 2 years, whereas 33 (89%) of 37 who had been given the low dose (ie, 300 000 pfu) remained seropositive for 2 years (p=0·042). In participants who had received a high dose, ZEBOV glycoprotein IgG GMCs decreased significantly between their peak (at 1-3 months) and month 6 after vaccination in Geneva (p0·05). Neutralising antibodies seem to be less durable, with seropositivity dropping from 64-71% at 28 days to 27-31% at 6 months in participants from the Geneva study. INTERPRETATION: Antibody responses to single-dose rVSV-ZEBOV vaccination are sustained across dose ranges and settings, a key criterion in countries where booster vaccinations would be impractical. FUNDING: The Wellcome Trust and Innovative Medicines Initiative 2 Joint Undertaking