Elucidation of novel, alternative, fiber-reinforced iron-based pozzolanic composites as SCMs

The researchers pioneered incorporating waste materials exhibiting pozzolanic properties and waste fibers from diverse industrial/agricultural fields into the construction industry to formulate enhanced, greener supplementary cementitious composites (SCMs). This research focused objectively on the formulation/evaluation of low-CO2-embodied greener construction materials known as “novel, alternative, fiber-reinforced iron-based binary/ternary pozzolanic composites (abbreviated as NAFRIC)”. The composites incorporated iron powder (Fe), metakaolin (MK), pulverized fly ash (PFA), ground granulated blastfurnace slag (GGBS), palm ash, silica fume, and limestone, which are anticipated to absorb CO2 while producing siderite (ferrous carbonate FeCO3). All the NAFRIC mixes formulated in this study demonstrated up to 4–13% improvement in compressive strength and 70–130% in flexural strength with an enhanced rupture modulus/post-crack ductility. The ternary pozzolanic iron-based fiber-reinforced concrete (FRC) composites containing 8% MK + 10% PFA + 10% GGBS and steel/polypropylene/polyethylene terephthalate (PET) fibers performed the best with attaining up to 70 MPa compressive and up to 8.9 MPa flexural strengths. The sulfate testing evaluated the durability of NAFRIC SCMs formulated in a 1:2:3 ratio better than cement concrete control mix with a 1:1:3 ratio. NAFRIC specimens demonstrated minimal surface deterioration/elongation and negligible/no strength reduction after 270 days of concentrated sulfate attack. The microstructural analysis using X-ray diffraction/fluorescence, scanning electron microscopy/energy-dispersive analysis with X-ray spectroscopy supported the strength and durability parameters by showing minimal/no ettringite formation and increased calcium silicate hydrates gel formation due to the use of FeCO3 and pozzolans. The study demonstrated the sustainable use of these better-performing NAFRIC SCMs with 10–12% reduced embodied CO2 as eco-friendly high-strength SCMs with enhanced engineering/environmental benefits

Effect of interventions to reduce malaria incidence among military personnel on active duty: study protocol for a cluster randomised controlled trial of the impact of etofenprox-treated uniforms, permethrin-treated uniforms and DEET insect repellent

BACKGROUND: While there is strong evidence that bite protection methods such as permethrin-treated clothing and topical insect repellents are protective against insect bites, there are few studies assessing the impact on malaria infection. This study will estimate the protective efficacy of treated uniforms and DEET insect repellent on the incidence of malaria infection among military personnel in an operational setting. Permethrin-treated uniforms used with DEET lotion will be compared to etofenprox-treated uniforms with DEET lotion. The effect of DEET lotion will be estimated by comparing permethrin-treated uniforms with DEET or placebo lotion. METHOD: A cluster randomised double-blind placebo-controlled trial is planned to evaluate the effectiveness of the interventions on preventing malaria infections in soldiers on active duty at Mgambo National Service Camp in Tanga, Tanzania. The arms are (1) permethrin-treated uniform with 30% DEET liposome formula; (2) permethrin-treated uniform with placebo lotion; (3) candidate insect repellent system, i.e. etofenprox-treated uniform with 30% DEET liposome formula; and (4) placebo, i.e. untreated uniforms with placebo lotion. The primary outcome is the incidence of Plasmodium falciparum malaria infection detected by polymerase chain reaction (PCR) by active case detection using surveys every 2 weeks for 12 months. Rapid diagnostic tests will be used for the diagnosis of participants with symptoms. The unit of randomisation will be combania: companies formed by recruits aged 18 to 25 years; combania do activities together and sleep in the same dormitory. Unequal randomisation will be used to optimise statistical power for the primary comparison between permethrin-treated uniforms with DEET and etofenprox-treated uniforms with DEET. DISCUSSION: This trial will provide the estimate of the effects of permethrin with DEET compared to those of the new fabric treatment etofenprox with DEET and any additional effect of using DEET. The results will inform strategies to protect military personnel and civilians who have more outdoor or occupational malaria exposure than the general public. TRIAL REGISTRATION: ClinicalTrials.gov NCT02938975

Switches of SOX17 and SOX2 expression in the development of squamous metaplasia and squamous intraepithelial lesions of the uterine cervix

Aims: The dynamics and topographical distribution of SOX17 and SOX2 expression was studied in the transformation zone (TZ) of the uterine cervix. This TZ is a dynamic area where switches from glandular into squamous epithelium can be recognized, new squamocolumnar junctions are formed, and premalignant lesions originate. SOX17 and SOX2 show mutually exclusive expression patterns in the normal uterine cervix, with SOX2 being exclusively found in squamous epithelium, while SOX17 is detected in endocervical columnar cells and reserve cells. Methods and Results: Normal cervices and squamous intraepithelial lesions (SIL) were studied with immunohistochemistry, methylation of SOX17, human papilloma virus (HPV) genotyping, and in situ hybridization. In the TZ squamous metaplasia originating from these reserve cells can still show SOX17 expression, while also remnants of SOX17-positive immature metaplasia can be recognized in the normal squamous epithelium. SOX17 expression is gradually lost during maturation, resulting in the exclusive expression of SOX2 in the majority of (SIL). This loss of SOX17 expression is independent of methylation of the CpG island in its promotor region. HPV can be detected in SOX17-positive immature metaplastic regions in the immediate vicinity of SOX2-positive SIL, suggesting that switches in SOX17 and 2 expression can occur upon HPV infection. Conclusions: This switch in expression, and the strong association between the distribution of reserve cells and squamous areas within the columnar epithelium in the TZ, suggests that reserve cell proliferations, next to basal cells in the squamous epithelium, are potential targets for the formation of squamous lesions upon viral infection

The Role of Lifelong Learning in Political Stability and Non-Violence: Evidence from Africa

Purpose – Education as a weapon in the fight against conflict and violence remains widely debated in policy and academic circles. Against the background of growing political instability in Africa and the central role of the knowledge economy in 21st century development, this paper provides three contributions to existing literature. It assesses how political stability/ non-violence is linked to the incremental, synergy and lifelong learning effects of education. Design/methodology/approach – We define lifelong learning as the combined knowledge acquired during primary, secondary and tertiary education. Principal component analysis is used to reduce the dimensions of educational and political indicators. An endogeneity robust dynamic system Generalized Methods of Moments is used for the estimations. Findings – We establish three main findings. First, education is a useful weapon in the fight against political instability. Second, there is an incremental effect of education in the transition from secondary to tertiary schools. Third, lifelong learning also has positive and synergy effects. This means that the impact of lifelong learning is higher than the combined independent effects of various educational levels. The empirical evidence is based on 53 African countries for the period 1996-2010. Practical implications – A plethora of policy implications are discussed, inter alia: how the drive towards increasing the knowledge economy through lifelong learning can be an effective tool in the fight against violence and political insurgency in Africa. Originality/value – As the continent is nursing knowledge economy ambitions, the paper is original in investigating the determinants of political stability/non violence from three dimensions of education attainment: the incremental, the lifelong learning and a synergy effect

Chronic suppurative otitis media in Tanzanian school children and its effects on hearing

Objectives: To compare different treatment regimens of chronic suppurative otitis media (CSOM) in school children, in regard to their consequence in hearing and discharge from the ear drum perforation. Design: Randomised controlled trial. Setting: Randomly selected primary schools within Dar es Salaam. Subjects: Three hundred and twenty eight children between 5-17 years of age with CSOM in one or both ears. Results: Three to four months after the onset of treatment 31% of group 1, 54% of group 2, and 56% of group 3, had dry ears. Treatment with dry mopping and boric acid in alcohol ear drops was significantly better than dry mopping alone. Adding amoxicillin to the treatment did not improve the end results. Hearing test performed before and after treatment showed that the hearing thresholds were the same or better after the treatment. The possible risk that boric acid in alcohol ear drops should lead to sensorineural hearing loss has not been confirmed. Conclusion: Based on the above results, the treatment of choice for CSOM in children in Dar es Salaam should be dry mopping and boric acid in spirit ear drops. East African Medical Journal Vol. 83(6) 2006: 322-32

A one-year prospective study on the occurrence of traumatic spinal cord injury and clinical complications during hospitalisation in north-east Tanzania

Background: Clinical complications following spinal cord injury are a big concern as they account for increased cost of rehabilitation, poor outcomes and mortality. Objective: To describe the occurrence of traumatic spinal cord injury and associated clinical complications during hospi- talisation in North-East Tanzania. Method: Prospective data were collected from all persons with traumatic spinal cord injury from North-East Tanzania from their admission to discharge from the hospital. Neurological progress and complications were assessed routinely. Data were captured using a form that incorporated the components of the core data set of the International Spinal Cord Society and were analysed descriptively. Results: A total of 87 persons with traumatic spinal cord injury were admitted at the hospital with a mean age of 40.2 ± 15.8 years. There were 69 (79.3%) males, and 58 (66.6%) of the injuries resulted from falls. Spasms (41 patients, 47.1%), neuropathic pain (40 patients, 46%), and constipation (35 patients, 40.2%) were the most commonly reported complications. The annual incidence rate in the Kilimanjaro region was at least 38 cases per million. Conclusion: The incidence of traumatic spinal cord injury in the Kilimanjaro region is relatively high. In-hospital compli- cations are prevalent and are worth addressing for successful rehabilitation

Antimicrobial and brine shrimp toxicity of some plants used in traditional medicine in Bukoba District, north-western Tanzania

Herbal medicines constitute a potentially important resource for new and safe drugs for the management of microbial infections and other diseases. In this study, dichloromethane, ethylacetate and ethanol extracts of Canarium schweinfurthii Engl., Dissotis brazzae Cong., Iboza urticifolia (Bak) E.A.Bruce, Isoglosa lacteal Lindau, Strombosia Scheffleri Engl., and Whitfieldia elongate T. Anders were tested for antimicrobial activity and brine shrimp toxicity. The objective was to validate claims that they are used to treat bacterial infections, diarrhoea and heal wounds among the Haya tribe of north-western Tanzania. At least one extract of each plant showed antibacterial activity. Dichloromethane extracts were the most active while ethanol extracts were the least active. Extracts of Whitfieldia elongate and Isoglossa lacteal were the most and least active with MICs in the range 0.08-0.62 mg/ml and 15.6-62.5 mg/ml, respectively. The dichloromethane extract of Whitfieldia elongate exhibited strong antifungal activity against Cryptococcus neoformans. Against brine shrimp larvae, the extracts from the six plants exhibited a low to very low toxicity with LC50 values ranging from 15.35-374.0μg/ml. However, ethanol extracts of Dissotis brazzae and Strombosia scheffleri had LC50 values of >1000μg/ml. The seemingly innocuous nature and relatively good antibacterial activity against skin infections and gastrointestinal pathogenic bacteria support the traditional uses of the plants and deserve more detailed studies

Early morning anopheline mosquito biting, a potential driver of malaria transmission in Busia County, western Kenya

Abstract Background Insecticide-treated nets (ITNs) contributed significantly to the decline in malaria since 2000. Their protective efficacy depends not only on access, use, and net integrity, but also location of people within the home environment and mosquito biting profiles. Anopheline mosquito biting and human location data were integrated to identify potential gaps in protection and better understand malaria transmission dynamics in Busia County, western Kenya. Methods Direct observation of human activities and human landing catches (HLC) were performed hourly between 1700 to 0700 h. Household members were recorded as home or away; and, if at home, as indoors/outdoors, awake/asleep, and under a net or not. Aggregated data was analysed by weighting hourly anopheline biting activity with human location. Standard indicators of human-vector interaction were calculated using a Microsoft Excel template. Results There was no significant difference between indoor and outdoor biting for Anopheles gambiae sensu lato (s.l.) (RR = 0.82; 95% CI 0.65–1.03); significantly fewer Anopheles funestus were captured outdoors than indoors (RR = 0.41; 95% CI 0.25–0.66). Biting peaked before dawn and extended into early morning hours when people began to awake and perform routine activities, between 0400–0700 h for An. gambiae and 0300–0700 h for An. funestus. The study population away from home peaked at 1700–1800 h (58%), gradually decreased and remained constant at 10% throughout the night, before rising again to 40% by 0600–0700 h. When accounting for resident location, nearly all bites within the peri-domestic space (defined as inside household structures and surrounding outdoor spaces) occurred indoors for unprotected people (98%). Using an ITN while sleeping was estimated to prevent 79% and 82% of bites for An. gambiae and An. funestus, respectively. For an ITN user, most remaining exposure to bites occurred indoors in the hours before bed and early morning. Conclusion While use of an ITN was estimated to prevent most vector bites in this context, results suggest gaps in protection, particularly in the early hours of the morning when biting peaks and many people are awake and active. Assessment of additional human exposure points, including outside of the peri-domestic setting, are needed to guide supplementary interventions for transmission reduction