Polycyclic aromatic hydrocarbons. A review

The recent literature describing polycyclic aromatic hydrocarbons (PAHs) in air, water, soil and sediment, waste sludge, biomonitoring, toxicity, are reviewed. Aspects of sampling, sample preparations such as extraction of PAHs are discussed and analytical methods used are also reviewed. Developments on direct measurement techniques, such as ultraviolet absorption spectrometry and synchronous luminescence, are noted. This review also discusses the microbial PAH-remediation and PAH-degradation with emphasis on biological and physico-chemical factors influencing the biodegradation

Synthesis of polypyrrole-Nafion composite films by gas phase electroformation

Nafion was introduced into polypyrrole (PPy) matrix by gas phase electrochemical polymerisation. This produced a uniform, homogeneous and conductive thin film of composite polymer. The films (PPy/Nafion) also show surface features of highly ordered structural regularity. The composites obtained were characterised by cyclic voltammetry (CV) and redox performance were investigated. The relationship of the anodic current of the composite with the various experimental parameters such as concentration of Nafion, current density, polymerisation time and temperature were investigated. Anodic current increases with the Nafion concentration, polymerising time, temperature and current density

Vapour phase polymerisation of conducting and non-conducting polymers: A review

Vapour phase polymerisation (VPP) is a well established technique in which the monomer is introduced to an oxidant-coated substrate in vapour form. Polymerisation then takes place at the oxidant vapour interface. VPP is a technique that could be used to immobilise materials to the modified electrode surface. This review article concentrates on the VPP of conducting polymers such as Polypyrrole (PPy) polythiophen (PT) and polyaniline (PANi). VPP of conducting polymers and other non-conducting polymers have extensively been investigated. This review article is divided into three main parts as given in Table of contents related to the VPP process of some important conducting polymers such as PPy, PT, PANi and Poly(3,4-ethylenedioxythiophene). A total of 181 references are cited in this review article and it attempts to look into VPP from inception of the method till present day

Rurality Forcing the Lights On: Is This Worth It?

Energy shortage is a major concern in Nigeria. Albeit its abundance, fossil fuel is no viable solution considering varied pollution. Renewable energy technology like solar-powered-hubfor-homes is gaining prominence. The technology positions to address energy deficit in rural households but first, household decision makers’ question of whether such investment is worth its cost demands answers. We assessed impact of this technology on wellbeing of adopting rural farming households in Nigeria and explored the drivers of its diffusion. Designing a Quasi-experiment, we randomly assigned 73 subscribers into treatment group and 219 nonelectrified households into control group. Data were analysed using descriptive statistics, t-test, PSM, and probit regression. We found adoption increased wellbeing of adopters over nonadopters(p<0.05) confirming our hypothesis that access to stand-alone solar-powered energy by off-grid rural households can potentially improve adopter’s personal wellbeing. We found that household and remittance incomes, within-household school-aged children, payment flexibility, subsidy scheme, peer effect and pursuit of life’s ease increased the probability of the technology adoption whereas increase in age, proximity to town and fossil fuel access negatively influenced its adoption (p<0.05). We recommended government subsidy on the technology. Diffusion may be aided by peer effect hence the recommendation to influence key individuals to adopt

Impact of the COVID-19 pandemic on patients with paediatric cancer in low-income, middle-income and high-income countries: a multicentre, international, observational cohort study

OBJECTIVES: Paediatric cancer is a leading cause of death for children. Children in low-income and middle-income countries (LMICs) were four times more likely to die than children in high-income countries (HICs). This study aimed to test the hypothesis that the COVID-19 pandemic had affected the delivery of healthcare services worldwide, and exacerbated the disparity in paediatric cancer outcomes between LMICs and HICs. DESIGN: A multicentre, international, collaborative cohort study. SETTING: 91 hospitals and cancer centres in 39 countries providing cancer treatment to paediatric patients between March and December 2020. PARTICIPANTS: Patients were included if they were under the age of 18 years, and newly diagnosed with or undergoing active cancer treatment for Acute lymphoblastic leukaemia, non-Hodgkin's lymphoma, Hodgkin lymphoma, Wilms' tumour, sarcoma, retinoblastoma, gliomas, medulloblastomas or neuroblastomas, in keeping with the WHO Global Initiative for Childhood Cancer. MAIN OUTCOME MEASURE: All-cause mortality at 30 days and 90 days. RESULTS: 1660 patients were recruited. 219 children had changes to their treatment due to the pandemic. Patients in LMICs were primarily affected (n=182/219, 83.1%). Relative to patients with paediatric cancer in HICs, patients with paediatric cancer in LMICs had 12.1 (95% CI 2.93 to 50.3) and 7.9 (95% CI 3.2 to 19.7) times the odds of death at 30 days and 90 days, respectively, after presentation during the COVID-19 pandemic (p<0.001). After adjusting for confounders, patients with paediatric cancer in LMICs had 15.6 (95% CI 3.7 to 65.8) times the odds of death at 30 days (p<0.001). CONCLUSIONS: The COVID-19 pandemic has affected paediatric oncology service provision. It has disproportionately affected patients in LMICs, highlighting and compounding existing disparities in healthcare systems globally that need addressing urgently. However, many patients with paediatric cancer continued to receive their normal standard of care. This speaks to the adaptability and resilience of healthcare systems and healthcare workers globally