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This research tends to investigate the influence of shielded metal arc welding (SMAW) parameters and flux compositions on the metallurgy of welded AISI 2205 duplex stainless steel (DSS). The consumable was developed using the Al2O3-TiO2-SiO2 flux system as major flux ingredients. The spectrophotometer was used for determining the chemical composition of the base core wire and the base plate. The six different fluxes (F1, F2, F3, F4, F5 and F6, with varied compositions were coated on a 3.2 mm diameter of ER2209 core wire with a coating factor of 1.65 mm. Basicity indexes of the six formulated fluxes were calculated to be less than 0.9 for the developed electrodes, which confirmed the electrodes to be acidic coated electrodes. The influence of welding parameters, particularly current on the hardness characteristics of the weldment was established to ascertain the integrity and applicability of the developed consumable. It was evident that the average welding current of 120A at a constant voltage of 22.5 V produced high hardness properties of the welded joint of DSS with an optimal heat input of 1.65KJ/mm. The hardness properties in most sceneries were observed to be high at heat affected zone (HAZ) and fusion zone (FZ) than in the base metal (BM) region which is attributed to the ferrite content. The average hardness value of the BM was found to be 241Hv/20, for the FZ and HAZ using the produced electrode F5 and F6 were found to be 250HV/20 and 301HV/20 respectively and for F6 was found to be 259HV/20 at FZ and 336HV/20 at the HAZ while that of the commercial electrode (C) was found to be: FZ-245/HV/20 and HAZ-319/HV/20 which is a good indication of its conformity to standard DSS. The SEM-EDS morphological characterization also reveals the austenite-ferrite phase with relatively coarse grains, inter-critical grains and fine grains at the HAZ regions of the welded joint.

A manually operated foot leverage pedal with adjustable blades guillotine cutter was designed and constructed using locally available materials. This machine was designed to shear variety of materials with various thicknesses and sizes depending on the cutting blade capacity and the shearing angle, which cuts the materials with minimal waste and without the formation of chips and bending of the material. The machine is foot powered. It works by first clamping the material with a ram. A moving blade then comes down across a fixed blade to shear the material. The moving blade was inclined at 0.5°, this angle is called the rake angle, to keep the material from becoming wedged between the blades. Test carried out on mild steel shows that the machine is capable of shearing the metal sheet with maximum thickness of 0.5mm.

The microstructure and mechanical properties of Al-Zn-Cu alloy with magnesium inclusion varying between 0.5 and 1.5 wt% were explored in this investigation. Al-Zn-Cu-Mg alloy was prepared by sand casting. Heat-treatment was done on the cast alloy samples at 460 °C for 2 h, which was then water-quenched. The samples at 160 °C were age-hardened for 5 h. Mechanical tests were done on both the heat-treated and as-cast alloy samples. Optical and scanning electron microscopy were used for the surface morphology of the samples. The maximum tensile strength (178.04 N/mm2) and hardness value (42.49 HB) were obtained from the Al-Zn-Cu-Mg alloy samples with 0.33 wt% Mg and 0.001 wt% Mg, respectively. In the as-cast samples, the reinforcing intermetallic phases present was coarse in nature while the precipitation hardened samples showed well-distributed reinforcing intermetallic phases which are fine grain size. Hence, the tensile strength of the cast Al-Zn-Cu-Mg alloy was positively influenced with the addition of magnesium while precipitation hardening eliminates micro segregations, thus, Al-Zn-Cu-Mg alloy mechanical properties were improved. Thus, the Al-Zn-Cu-Mg alloy can be useful in automobile industry.

This study considers the physical and tribological properties of hybrid reinforced aluminium matrix composites using Al 6063 alloy and silicon carbide (SiC) and palm kernel shell ash (PKSA) as reinforcements. The reinforcements used were 0, 2, 4, 6, 8, and 10 wt% in the matrix metal at different ratios of the SiC and PKSA using the double stir casting method. Experimental density and porosity of the samples were determined. Taber wear abrasion tester was utilized in the wear test experimentation. The results disclosed that the density of the composite reduced with PKSA increment, while other samples with SiC increment have improved density. The porosity percentage results showed that the double stir casting method used was acceptable as the values were within the permissible limit for cast MMCs. The sliding speed and applied load increment increased the mass loss and wear index for all the samples.

This study is geared towards evaluating the physico-thermal and mechanical properties of fibreglass-ceramic-adansonia digitata’s fibres reinforced epoxy composite with relatively fire-resistant behaviour to validate its effectiveness in most applications. The composite was developed with the aid of a seamless manual hand lay-up technique. The Adansonia digitata fibre and the constituent matrix ratio were thoroughly mixed to obtain a homogenous paste which was then allowed to cure using the compressive moulding machine for 7 min. Different volumetric compositions were obtained using the Taguchi L9 (3)3 orthogonal array method for the experimental design. Physico-mechanical analyses were carried out on the developed composite. The Thermogravimetric Analysis (TGA) and Scanning Electron Microscope (SEM) were done to determine the thermal stability and morphological characteristics of the composite respectively. It was evident from the experiment that the developed composites possessed better mechanical and thermal properties with good performance than the control sample, which can serve as a superior alternative for conventional fibres as both for fire resistance and other engineering applications.

This research aimed at developing crash helmet from musa-paradisiaca’s (plantain) fiber (MPF) as a reinforced composite material which tends to remedy the problem of heavy weight conventional metallic materials. The helmet was produced by hand lay-up method using plaster of Paris as the mould. The fiber used was extracted from a plantain pseudo-stem which was harvested in a local plantation and polyester resin was used as the matrix which was infused to reinforce the composite. Finite Element Analysis (FEA) was used to simulate the performance of the helmet developed. It was observed from the experiment that the plantain fibers reinforced with polyester composite exhibited superior properties which is a good alternative for the conventional materials.

Many attempts have been made to improve the overall efficiency as well as working conditions of Injera baking stoves at different instances. In this article, a mechanism to partially automate electric Injera baking stove was introduced aiming to increase the efficiency and production rate of Injera baking. The mechanism involves a link and pulley system that generates a spiral motion. The mechanism was manufactured and assembled to a hose system connected to a batter reservoir that allows the flow of Injera batter forming the ideal disc shaped Injera on a baking pan upon five complete rotations. A thermostat was incorporated to reduce energy loss due to baking pan overheating. The mean efficiencies of the conventional and the developed Injera baking stove were found to be 57.46% with a standard deviation value of 5.52 and 87.38% with a standard deviation value of 8.21 respectively. About 30 % efficiency increase was observed. While the production rate was improved by 6.12% as compared to the conventional backing stove.

Alzheimer disease (AD) is the most common form of dementia contributing to about 60–70% of cases. β-Site amyloid precursor protein cleaving enzyme-1 (BACE1) plays an important role in the onset of AD and has become one of the important drug targets for AD. This approach has led to the development of promising BACE1 inhibitors, many of which are going through different phases of clinical trials. Nonetheless, the high failure rate of lead drug candidates targeting BACE1 brought to the forefront the need for finding new drugs to uncover the mystery behind AD. This study focused on virtual screening of ~ 33,000 natural compounds to find potential BACE1 inhibitors. Multiple ligands pharmacophore model was generated using PHASE to screen retrieved compounds against a four-site (ADDR) hypothesis. Molecular docking was performed to predict the binding status of the natural compounds. Based on binding affinity, the top eight compounds were chosen for further analysis. The docked complexes were analyzed for binding free energy using PRIME MM/GBA calculation. The compounds were filtered for drug-likeness using ADME/TOX (absorption, distribution, metabolism, excretion and toxicity) prediction. AutoQSAR (automated quantitative structure activity relationship) was used to build a model for the prediction of compounds bioactivities. Despite retrieving a large number of compounds with favorable binding affinity, only a few were selected to be promising based on their ADME/TOX proprieties, binding free energy and predicted pIC50. This study identified four natural compounds (NPC469686, NPC262328, NPC29763 and NPC86744) as novel BACE1 inhibitors. The insights obtained from this study could be employed to produce next-generation drug for AD.

Anaemia is a condition commonly encountered in many clinical specialities, including chronic heart disease, haemato-oncology, gastroenterology, gynaecology/obstetrics, renal disease and care of the elderly. In recent years, anaemia has emerged as a significant public health issue due to the appreciation that it has profound implications as a comorbid factor for other illnesses, while in itself presenting a serious health risk factor. This article explores the definition, classification and current treatment options for anaemia. It describes the move within a central London acute trust to a nurse-led service and the favourable patient satisfaction results that have emerged from an initial survey.

Intravenous iron therapy is a useful treatment for the rapid correction of iron deficiency anaemia and can be used to avoid or reduce the requirement for allogeneic blood transfusion. Several intravenous iron preparations are available commercially which differ in cost, mode of administration and side effect profile. There are few data directly comparing the efficacy of these preparations. In this retrospective single-centre study, we present the results from two hundred and eight patients treated using three different iron preparations (iron dextran, iron sucrose and ferric carboxymaltose) and compare the effect on haemoglobin levels and other measures of iron deficiency six weeks after treatment. Within the limitations of our study design, we show a statistically and clinically significant difference in efficacy between these preparations.

Deepti Radia,1 Ibrahim Momoh,2 Richard Dillon,1 Yvonne Francis,1 Laura Cameron,1 Toni-Lee Fagg,1 Hannah Overland,1 Susan Robinson,1 Claire N Harrison11Haematology Department, Guy's and St Thomas' NHS Foundation Trust, London, UK; 2Bupa Home Healthcare, Harlow, UKAbstract: This article describes the initiation and evolution of the Rapid-Access Anemia Clinic (RAAC) at Guy's and St Thomas' Hospitals, London, UK. This clinic was set up to provide diagnosis and treatment, and to coordinate investigative procedures, where necessary, into the underlying causes of anemia. Initially piloted with anemic preoperative orthopedic patients, the clinic now treats a wide range of conditions, deriving from both internal and external referrals. Treatment includes dietary advice, supplementation with iron, vitamin B12 and folate, and blood transfusion. Most patients at the RAAC need iron replacement, the majority of which require intravenous (IV) iron. Therefore the first-line IV iron-administration protocol is carefully considered to ensure viability of the service and patient satisfaction. Four IV irons available in the UK are discussed, with explanation of the benefits and drawbacks of each product and the reasoning behind the IV iron choice at different stages of the RAAC's development. Costs to the service, affected by IV iron price and administration regimen, are considered, as well as the product's contraindications. Finally, the authors reflect on the success of the RAAC and how it has improved patients' quality-of-treatment experience, in addition to benefiting the hospital and National Health Service in achieving specific health-care mandates and directives. Drawing from the authors' experiences, recommendations are given to assist others in setting up and providing a successful rapid-access anemia service or similar facility.Keywords: hemoglobin, iron deficiency, ferric carboxymaltose, iron sucrose, iron dextran, iron isomaltosideA Letter to the Editor has been received and published for this article.

Abstract 4368 Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired bone marrow disorder characterised by intravascular hemolysis with resultant anemia often leading to transfusion dependence, severe disabling symptoms and, frequently, life threatening thrombosis. Historically the management of PNH was largely supportive, relatively ineffective and resulted in frequent visits to hospital, admissions, an inability to function normally including loss of employment or other daily activities. PNH is a chronic condition and in most patients persists for the remainder of the patient’s life. Eculizumab was first used for PNH in 2002 and has been licensed since 2007. Eculizumab has been reported to improve all symptoms due to hemolysis in PNH as well as preventing the common complications, such as thrombosis and renal failure and normalising survival. However eculizumab has to be given as an intravenous infusion every 2 weeks indefinitely. In the UK PNH is managed in a shared care model between local hematologists and the National PNH Service from two Centres based in St James’s University Hospital, Leeds and Kings College Hospital, London. Here we report the management of patients treated with eculizumab within the PNH National Service. A total of 130 patients have been treated with eculizumab since May 2002 with 120 currently receiving therapy. 5 patients have died and none were directly related to PNH or eculizumab. 99 patients requiring transfusions prior to eculizumab have been on treatment for at least a year and 65 (66%) of these have not required transfusions for at least the last 12 months. The rarity of PNH means that patients frequently have to travel long distances for review and treatment. This leads to major issues both in terms of time commitment and expense. In order to allow patients to lead as normal lives as possible we have developed a service model in which Specialist PNH Clinics are performed regionally by the PNH Centre and in which patients receive eculizumab every 2 weeks in their homes delivered by a homecare nursing team. In the UK, the PNH Service and Healthcare at Home Ltd (www.hah.co.uk) have been working in partnership for over 7 years during the clinical trials of eculizumab and since its license in 2007. The PNH Service manages the prescription and delivery of eculizumab including an education program for the homecare nurses. This innovative home infusion programme ensures the safe administration of eculizumab outside of the hospital environment, leading to enhanced treatment-associated convenience for patients and their families. Each year the home infusion program has grown, now over 3000 infusions are given annually including whilst patients are on holiday, visiting family, at University or in the workplace. A recent patient survey has been conducted from the 2 PNH Centres to assess the patients’ experience of their PNH diagnosis and treatment. 122 patients responded with 70 of these patients receiving treatment with eculizumab and all currently on the home infusion programme. 63 of 68 patients reported the homecare service as excellent or very good compared to 1 reporting it as poor and 66 of the 68 patients preferred to have their treatment at home compared to hospital. The patients main concerns before starting treatment were reduced life expectancy and the requirement for blood transfusions along with fatigue. With eculizumab treatment and the convenience of homecare 30 patients reported being able to return to work. The homecare service is supported by contact between the clinic appointments, 56 of 67 patients having contact with their PNH Specialist Centre by phone or email in addition to the care of the patient’s local hematology team that over 90% of the patients continue to see. The impact of PNH on patients lives before eculizumab treatment was rated and improved from a median of 3 out of 10 (0 = no quality of life; 10 = normal) prior to eculizumab to a median of 8 out of 10 on treatment. In summary, a novel model of provision of care in PNH with Outreach Specialist Clinics, a 24 hour on call service and homecare delivery of eculizumab permits the normalisation of patients’ lives and overcomes most of the hurdles associated with prolonged regular intravenous therapy. This allows patients to benefit fully from eculizumab including reduction in transfusions, the prevention of serious complications, normalisation of quality of life and where appropriate a return to work. Disclosures: Arnold: Alexion Pharmaceuticals: Honoraria. Kelly:Alexion Pharmaceuticals: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau. Hill:Alexion Pharmaceuticals: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau. Richards:Alexion Pharmaceuticals: Honoraria, Speakers Bureau. Elebute:Alexion Pharmaceuticals: Honoraria, Membership on an entity’s Board of Directors or advisory committees. Hillmen:Alexion Pharmaceuticals: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding, Speakers Bureau.

Abstract 4240 Background: PNH is an acquired haemolytic anaemia which is characterised by intravascular haemolysis. The disease is due to a somatic mutation of the PIG-A gene in haematopoietic stem cells resulting in loss (complete or partial) of glycosylphosphatidylinositol-(GPI) anchored proteins on the cell surface. The lack of CD59, one of the GPI-anchored proteins, on the red cell surface leads to increased susceptibility to complement-mediated intravascular haemolysis. Eculizumab is a monoclonal antibody that inhibits the complement protein C5 by preventing its cleavage and leads to transfusion independence in 50% of the patients. Objective: To determine the role of C3 –mediated opsonisation of PNH cells, as we found a significant number of patients treated with Eculizumab still needing transfusion. Results: Twenty six PNH patients treated with Eculizumab and 22 patients from an untreated non transfusion dependant PNH cohort were analysed. Transfusion dependency was present in 14 of 26 patients (54%) compared with transfusion independence in 12/26 (46%) patients. Direct anti-globulin test (DAT) was positive in 21 of 26(81%) patients during eculizumab treatment, while DAT was positive in 2 of 24 untreated patients (8%).All except one patient (20/21) with positive DAT had C3d positivity at varying levels. There was no correlation between the strength of C3d positivity and transfusion dependency. Of the 21 patients who had a positive DAT during eculizumab treatment, samples were available for 16 patients prior to treatment, and 7 of 16 were DAT positive. All the 7 patients were weakly positive for IgG and only one patient had C3d positivity at a low level. The two untreated patients were also only weakly positive for IgG. Among the eculizumab treated patients, 14 of the 21(67%) with a positive DAT test received at least two transfusions compared with no transfusions in the 5 DAT negative patients (p Conclusion: Eculizumab treatment in PNH patients has resulted in significant reductions in transfusions in a majority of patients, though some patients still require transfusion at a low intensity. The observation of C3 fragments on PNH red cells reveals an extravascular haemolytic pathway which is unmasked by Eculizumab treatment as evidenced by finding new DAT positive tests. The finding of positive DAT test in a 9 of 50(18%) untreated haemolytic PNH patients demonstrates the utility of flow cytometry to analyse PNH clones when clinical suspicion is high, as conventionally finding DAT positivity indicates autoimmune haemolytic process and excludes diagnosis of PNH. The true detection of C3d on red cells causing a positive DAT test post treatment, rather than due to allo-antibodies is important. There is a proportion of patients (33%) who became DAT positive but never needed transfusion indicating the contribution of other factors like bone marrow failure, intercurrent infections in the transfusion dependent DAT positive group. Eculizumab is effective in resolution of intravascular haemolysis, but unmasking of low level C3d mediated haemolysis is an important phenomenon which is not entirely responsible for the persistent transfusion requirement in a subset of patients. Disclosures: No relevant conflicts of interest to declare.