Economic Appraisal Of Industrial Solar Drying (Part I)

Major goals of industrialization include but not limited to provision of employment, establishing a platform for overall national development and improving the monetary income of whoever is involved which invariably improves the standard of living. A better pre-visibility study must encompass a well analysed economic appraisal of the plan. Computer programme was generated to analyse the economic aspect of industrial solar drying. The appraisal was carried out with the software using the Life Cycle Savings (LCS) technique. Three locations in Nigeria (i.e. Ibadan, Kano and Port Harcourt) were selected and their respective economic appraisal simulated. Sample simulations reveal that at a realistic initial moisture content of 30% (% wet basis) of the agricultural produce, economic analysis of over 20 years reveal that recommended solar collector area of 85.46m2, 80.71m2 and 75.96m2 supplied about 67%, 88% and 55.8% of the annual energy needed for Ibadan, Kano and Port-harcourt respectively which are the specific sizes at which life cycle solar savings are optima

Room temperature phytosynthesis of silver nanoparticles using leaf extract of Momordica charantia: optical and antimicrobial properties

Nigeria is endowed with rich diversity of medicinal plants whose potential as “green” reducing agents are under-utilized. As the world is advocating for safe environment, plant-mediated synthesis of nanoparticles is considered as an eco-friendly and sustainable synthetic route instead of using toxic chemicals. The method is fast, easy and cheaper compared with other conventional techniques. In this study, phytochemicals present in the leaf extract of indigenous Momordica charantia served as reducing, capping/stabilizing agents. The synthesized silver nanoparticles were characterized with Uv-vis spectrophotometer, photoluminescence (PL) and energy- dispersive x-ray spectrometer (EDX). Antimicrobial activities of the synthesized nanosilver were investigated on isolated Streptococcus pyogenes, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa Candida albicans and Trichophyton rubrum. Optical measurement showed surface plasmon resonance with broad absorption peaks (400-450 nm). Significant growth inhibitions were also found at P <0.05 by means of analysis of variance SPSS tool. The leaf influenced nanosilver displayed highest activity on S. aureus, S. pyogenes and E. coli with MIC and MBC value of 12.5 mg/mL. Least activity was detected against P. aeruginosa (50 mg/mL MIC and 100 mg/mL MBC). From this work, the biogenic nature and optical properties displayed by the as-prepared nanosilver strongly suggest its applications as candidate for therapeutic drugs, diagnostic and medical imaging

Life path analysis: scaling indicates priming effects of social and habitat factors on dispersal distances

1. Movements of many animals along a life-path can be separated into repetitive ones within home ranges and transitions between home ranges. We sought relationships of social and environmental factors with initiation and distance of transition movements in 114 buzzards Buteo buteo that were marked as nestlings with long-life radio tags. 2. Ex-natal dispersal movements of 51 buzzards in autumn were longer than for 30 later in their first year and than 35 extra-natal movements between home ranges after leaving nest areas. In the second and third springs, distances moved from winter focal points by birds that paired were the same or less than for unpaired birds. No post-nuptial movement exceeded 2 km. 3. Initiation of early ex-natal dispersal was enhanced by presence of many sibs, but also by lack of worm-rich loam soils. Distances travelled were greatest for birds from small broods and with relatively little short grass-feeding habitat near the nest. Later movements were generally enhanced by the absence of loam soils and short grassland, especially with abundance of other buzzards and probable poor feeding habitats (heathland, long grass). 4. Buzzards tended to persist in their first autumn where arable land was abundant, but subsequently showed a strong tendency to move from this habitat. 5. Factors that acted most strongly in ½-km buffers round nests, or round subsequent focal points, usually promoted movement compared with factors acting at a larger scale. Strong relationships between movement distances and environmental characteristics in ½-km buffers, especially during early ex-natal dispersal, suggested that buzzards became primed by these factors to travel far. 6. Movements were also farthest for buzzards that had already moved far from their natal nests, perhaps reflecting genetic predisposition, long-term priming or poor habitat beyond the study area

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Estimation de directions d'arrivée en présence d'erreur de phase

National audienc

Synthesis of Silver Nanoparticles by Plant-Mediated Green Method: Optical and Biological Properties

In this study, silver nanoparticles (Ag NPs) were successfully synthesized by plant-mediated green route. The leaf extracts of locally sourced Canna indica and Senna occidentalis acted as the reducing agents/capping agents instead of toxic chemicals leading to unprecedented bioreduction which promoted nucleation and particle growth within 2 minutes of reaction. Optical measurements were characterized by high intensities of absorption revealed by narrow absorption peaks indicating confinement of excitons, with surface Plasmon resonance (SPR) bands of silver nanoparticles at 340–380 nm (S. occidentalis-stabilized Ag NPs) and 400–430 nm (C. indica-stabilized Ag NPs). Morphological characterization with scanning electron microscope coupled with energy dispersed spectrometer (SEM-EDS) and transmission electron microscope (TEM) revealed quasi-spherical, cubic and truncated edge Ag NPs with mean sizes of 9.10 ± 1.12 nm and 9.4 ± 1.95 nm. Formation of crystalline Ag NPs was also supported by X-ray diffraction (XRD) pattern and selected area electron diffraction (SAED) showing peak broadening. FTIR analysis revealed some characteristic vibrational bands of O–H, C=O, C=N functional groups at 3306, 1647 and 1246 cm–1 respectively in the organically capped silver nanoparticles. The mechanism of reaction in both syntheses was considered to be diffusion controlled Ostwald ripening process. The antimicrobial activity of the synthesized nanoparticles was tested against clinically isolated Gram positive bacteria: Staphylococcus aureus , Streptococcus pyogenes and clinically isolated fungus-Candida albicans. Significant growth inhibitions were found using analysis of variance (ANOVA), SPSS statistical tool at P < 0.05. The highest activity of C. indica-synthesized Ag NPs was against C. albicans, while S. occidentalis-derived Ag nanoparticles were most active against S. aureus and S. pyogenes. Hence, the findings of this research suggest potential applications of the bionanoparticles as optical materials, electronically conductive adhesives (ECA), and as a candidate for therapeutic drugs because of their biogenic nature