Phytotoxicity Level and Effects of Arsenic Phytoextraction using Helianthus Annuus L. (Sunflower)

Arsenic is one of the most deadly contaminants polluting the environment in many countries of the world today. It occurs naturally in many ores (Copper, Lead, Gold etc.), but human activities (like explosions, mining, pesticides applications etc.) and natural occurrences (like volcanoes, micro-organisms activities) have increased its amount in the environment to lethal levels. This research involved the growing of sunflower plants Helianthus annuus L. collected from the Institute of Agricultural Research and Training (IAR&T) on various concentrations of Arsenate contaminated soil for Arsenic phyto-extraction for seven weeks to know the phyto-toxicity level of Arsenic on sunflower (an Arsenic hyper-accumulator). After several observations and statistical evaluations using the Analysis of Variance, it was discovered that as from 2.0g – 3.0g of Arsenate per kg of soil, 0% germination occurred. Between 0.75g – 1.5g of Arsenate per kg of soil, the percentage germination was 10% - 50% (not significant) and percentage survival was 30% (not significant). Furthermore, between 0g – 1.5g of Arsenate per kg of soil, there was a percentage germination of 60% - 100% (significant) and a percentage survival of 60% - 100% (significant). Hence, for efficient and appreciable Arsenic phyto-extraction from an Arsenate contaminated soil using Sunflower a concentration of 0.5g and below of Arsenate per kg of soil should be ensured. As from 0.75g of Arsenate per kg of soil (Phytotoxicity level) the effects of Arsenic phyto-toxicity observed are delayed germination, wilting, drying-off, damping-off, foliage chlorosis and necrosis, reddening etc. Keywords:Phytoextraction, phytotoxicity, arsenic, sunflower, arsenate contaminated soi

Phytotoxicity Level and Effects of Arsenic Phytoextraction using Helianthus Annuus L. (Sunflower)

Arsenic is one of the most deadly contaminants polluting the environment in many countries of the world today. It occurs naturally in many ores (Copper, Lead, Gold etc.), but human activities (like explosions, mining, pesticides applications etc.) and natural occurrences (like volcanoes, micro-organisms activities) have increased its amount in the environment to lethal levels. This research involved the growing of sunflower plants Helianthus annuus L. collected from the Institute of Agricultural Research and Training (IAR&T) on various concentrations of Arsenate contaminated soil for Arsenic phyto-extraction for seven weeks to know the phyto-toxicity level of Arsenic on sunflower (an Arsenic hyper-accumulator). After several observations and statistical evaluations using the Analysis of Variance, it was discovered that as from 2.0g – 3.0g of Arsenate per kg of soil, 0% germination occurred. Between 0.75g – 1.5g of Arsenate per kg of soil, the percentage germination was 10% - 50% (not significant) and percentage survival was 30% (not significant). Furthermore, between 0g – 1.5g of Arsenate per kg of soil, there was a percentage germination of 60% - 100% (significant) and a percentage survival of 60% - 100% (significant). Hence, for efficient and appreciable Arsenic phyto-extraction from an Arsenate contaminated soil using Sunflower a concentration of 0.5g and below of Arsenate per kg of soil should be ensured. As from 0.75g of Arsenate per kg of soil (Phytotoxicity level) the effects of Arsenic phyto-toxicity observed are delayed germination, wilting, drying-off, damping-off, foliage chlorosis and necrosis, reddening etc. Keywords: Phytoextraction, phytotoxicity, arsenic, sunflower, arsenate contaminated soi

IN VITRO Proliferation of Plantain using Different Concentration of Auxin and Cytokinin

This study was carried out in the Tissue Culture Laboratory of Nigerian Agricultural Quarantine Service (NAQS), moor plantation, Ibadan. The explants used were obtained from National Horticultural Research Institute (NIHORT) and the growth parameter studied is the number of proliferated buds. MS (Murashige and Skoog) media supplemented with 0.18mgl-1NAA + 2.3mgl-1BAP supported the growth and bud formation in meristem culture of Musa paradisiaca cv. Agbagba during the initiation stage. After the first apical buds appeared, the buds were transferred to MS media supplemented with different combinations of Naphthalene acetic acid (NAA) and Benzylaminopurine (BAP) at different concentrations (0.0mgl-1NAA + 0.0mgl-1BAP, 0.1mgl-1 NAA + 3.5mgl-1 BAP, 0.18mgl-1 NAA + 4.5mgl-1 BAP, 0.26mgl-1 NAA + 5.5mgl-1 BAP). The results obtained showed that proliferation media supplemented with 0.18mgl-1 NAA + 4.5mgl-1 BAP yielded the highest number of buds. This study however revealed the effect of hormone in the initiation and proliferation of plantain buds as essential and MS medium with NAA (0.18mgl-1) and BAP (4.5mgl-1) was the optimum concentration required for the proliferation of plantain. Keywords: Optimum concentration, In-vitro, MS medium, proliferated bud

Effect of cathodic protection methods on ferrous engineering materials under corrosive wear conditions

Cathodic protection prolongs the service life of fluid transport and offshore engineering components by suppressing corrosion. This study assesses the effect of two cathodic protection methods, such as impressed current cathodic protection (ICCP) and sacrificial anode cathodic protection (SACP), on three ferrous-based materials under laboratory-controlled corrosive wear conditions. The SACP was as effective as ICCP on the protection of the low alloy steel and white chromium cast iron under both solid and solid-free corrosive wear conditions. Under solid–liquid impingement, significant reductions in the material loss were also observed in both the direct impingement zone and the outer area (oblique angle of attack). This demonstrates the substantial impact of cathodic protection systems that are exposed to erosion–corrosion dominated environments

Biodegradable polymer sirolimus-eluting stents versus durable polymer everolimus-eluting stents in patients with ST-segment elevation myocardial infarction (BIOSTEMI): a single-blind, prospective, randomised superiority trial

Background: Newer-generation drug-eluting stents that combine ultrathin strut metallic platforms with biodegradable polymers might facilitate vascular healing and improve clinical outcomes in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention (PCI) compared with contemporary thin strut second-generation drug-eluting stents. We did a randomised clinical trial to investigate the safety and efficacy of ultrathin strut biodegradable polymer sirolimus-eluting stents versus thin strut durable polymer everolimus-eluting stents in patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing primary PCI. Methods: The BIOSTEMI trial was an investigator-initiated, multicentre, prospective, single-blind, randomised superiority trial at ten hospitals in Switzerland. Patients aged 18 years or older with acute STEMI who were referred for primary PCI were eligible to participate. Patients were randomly allocated (1:1) to either biodegradable polymer sirolimus-eluting stents or durable polymer everolimus-eluting stents. Central randomisation was done based on a computer-generated allocation sequence with variable block sizes of 2, 4, and 6, which was stratified by centre, diabetes status, and presence or absence of multivessel coronary artery disease, and concealed using a secure web-based system. Patients and treating physicians were aware of group allocations, whereas outcome assessors were masked to the allocated stent. The experimental stent (Orsiro; Biotronik; Bülach, Switzerland) consisted of an ultrathin strut cobalt–chromium metallic stent platform releasing sirolimus from a biodegradable polymer. The control stent (Xience Xpedition/Alpine; Abbott Vascular, Abbott Park, IL, USA) consisted of a thin strut cobalt–chromium stent platform that releases everolimus from a durable polymer. The primary endpoint was target lesion failure, a composite of cardiac death, target vessel myocardial reinfarction (Q-wave and non-Q-wave), and clinically-indicated target lesion revascularisation, within 12 months of the index procedure. All analyses were done with the individual participant as the unit of analysis and according to the intention-to-treat principle. The trial was registered with ClinicalTrials.gov, number NCT02579031. Findings: Between April 26, 2016, and March 9, 2018, we randomly assigned 1300 patients (1623 lesions) with acute myocardial infarction to treatment with biodegradable polymer sirolimus-eluting stents (649 patients and 816 lesions) or durable polymer everolimus-eluting stents (651 patients and 806 lesions). At 12 months, follow-up data were available for 614 (95%) patients treated with biodegradable polymer sirolimus-eluting stents and 626 (96%) patients treated with durable polymer everolimus-eluting stents. The primary composite endpoint of target lesion failure occurred in 25 (4%) of 649 patients treated with biodegradable polymer sirolimus-eluting stents and 36 (6%) of 651 patients treated with durable polymer everolimus-eluting stents (difference −1·6 percentage points; rate ratio 0·59, 95% Bayesian credibility interval 0·37–0·94; posterior probability of superiority 0·986). Cardiac death, target vessel myocardial reinfarction, clinically-indicated target lesion revascularisation, and definite stent thrombosis were similar between the two treatment groups in the 12 months of follow-up. Interpretation: In patients with acute STEMI undergoing primary PCI, biodegradable polymer sirolimus-eluting stents were superior to durable polymer everolimus-eluting stents with respect to target lesion failure at 1 year. This difference was driven by reduced ischaemia-driven target lesion revascularisation in patients treated with biodegradable polymer sirolimus-eluting stents compared with durable polymer everolimus-eluting stents. Funding: Biotronik