187 research outputs found

    Automatic Classification of Bright Retinal Lesions via Deep Network Features

    Full text link
    The diabetic retinopathy is timely diagonalized through color eye fundus images by experienced ophthalmologists, in order to recognize potential retinal features and identify early-blindness cases. In this paper, it is proposed to extract deep features from the last fully-connected layer of, four different, pre-trained convolutional neural networks. These features are then feeded into a non-linear classifier to discriminate three-class diabetic cases, i.e., normal, exudates, and drusen. Averaged across 1113 color retinal images collected from six publicly available annotated datasets, the deep features approach perform better than the classical bag-of-words approach. The proposed approaches have an average accuracy between 91.23% and 92.00% with more than 13% improvement over the traditional state of art methods.Comment: Preprint submitted to Journal of Medical Imaging | SPIE (Tue, Jul 28, 2017

    Teachers\u27 perceptions of professional identity and communities of practice

    Get PDF
    This study investigates the perceptions of English instructors on their professional identities, within private higher education institutions. The aim of the current study is to explore the perceptions of teachers\u27 professional identities and the aspects that affect it, as well as, their perceptions of communities of practice and its effect on their professional identity. The study is conducted on 26 English instructors, who teach Academic English in private institutions. A qualitative approach is utilized and individual interviews, and focus group interviews were conducted with all the participants. Findings show that there are four main aspects that shape and affect a teacher\u27s professional identity, such as teacher role, appreciation and connection, competence and self-efficacy, and future trajectories. These aspects seem to highly affect the instructors\u27 professional identity in a positive way. Moreover, the teachers are aware of the significance of self-reflection and professional improvement. Furthermore, there is an indication that membership in communities of practice is a crucial action in order to improve teachers\u27 teaching skills, share common experiences and enhance social learning (Wenger, 1998). In addition, participants believe that it is a method for developing their performance to enhance their students\u27 academic learning. Data also shows that it has a positive effect on teachers\u27 professional identities. The study suggests some practical implications that could assist teacher educators, and if applied in teacher education programs and trainings could help in supporting and developing their professional identities

    Stabilisation of clay subgrade soils using ground granulated blastfurnace slag

    Get PDF
    Roads constructed on expansive clays may be adversely affected by the behaviour of the clay. Expansive clays suffer volume change due to changes in moisture content which causes heaving, cracking and the break up of the road pavement. Stabilisation of these types of soil is necessary to suppress swelling and increase the strength of the soil and thus partially decrease the thickness of road pavement layers. The use of by-product materials for stabilisation has environmental and economic benefits. Ground granulated blastfurnace slag (GGBS), a by-product material in Egypt, and lime are used in the current work to stabilise samples of a clay soil similar to a typical Egyptian clay soil. This test soil comprises 80% River Aire soil and 20% calcium montmorillonite. The main objectives of this research were to investigate the effect of GGBS, with and without lime, on the engineering behaviour (plasticity characteristics, compaction, unconfined compressive strength (UCS) and swelling potential) of the test soil and to identify the reaction products of the stabilised materials to determine the mechanisms by which changes in engineering properties are obtained. In order to achieve these objectives, extensive laboratory investigations were carried out. Various mixes (up to 10% GGBS by dry weight of the test soil and up to 30% replacement by hydrated lime) were prepared and cured under two representative conditions {20°C with 90-100% relative humidity (CCI) and 35° C with 50-60% relative humidity (CC2)} for up to 12 months. Compaction and plasticity were measured soon after mixing, the swelling potential and UCS were measured after longer curing periods. Four analytical techniques {X ray diffraction, scanning electron microscopy, differential thermal analysis and nuclear magnetic resonance (NMR)} were used to identify the reaction products of the clay fraction of the test soil mixed with various amount of GGBS and lime. This pure clay test soil was used to ease identification of the reaction products. The investigations showed that generally the engineering properties (UCS, swelling, plasticity) improved with the addition of GGBS and with increasing curing period and temperature. The addition of lime resulted in a dramatic improvement within the test ranges covered in the programme. The maximum dry density, MDD, decreased and the optimum moisture content, OMC, increased with increasing GGBS and lime content. The major changes in the UCS and swelling behaviour are due to the formation of new cementitious materials. The analytical investigation confirmed two major reactions when GGBS and lime were added to the pure clay soil, hydration of GGBS activated by lime to produce calcium aluminosilicate hydrate gel (C-A-S-H) and hydrotalcite type phase, and the clay-lime reaction to produce calcium silicate hydrate (C-S-H), (C-A-H) and (C-A-S-H). The NMR test results revealed that the aluminosilicate chain length (EL), the aluminium: silicate (Al/Si) ratio and the amount of Si in the formed C-S-H significantly increased with an increase in the curing temperature and period, which indicates a more stable and well crystalline C-S-H. The results indicate that the use of GGBS alone, or preferably with lime, could have a significant effect on the behaviour of potentially swelling clays. Recommendations for further studies include a study of the effect of cyclic loading on the test soil. Also, site trials should be carried out to assess the suitability of using these materials in the field

    Role of Corticosteroids versus Hyaluronic Acid in Healing of Sciatic Nerve Injury in Male Albino Rats

    Get PDF
    Background: Peripheral nerve lesions are common and severe injuries that impact about 2.8% of traumatic patients annually, and result in lifetime disability if untreated. Objective: This study aimed to investigate the effect of corticosteroids vs hyaluronic acid in peripheral nerve healing in rats. Patients and methods: This was experimental and histopathological study that had included (18) Sprague-Dawley rats with an average weight of 300–350 gm. All rats were divided into three groups (n=6 per group). Group 1; Corticosteroids was injected under epineurium after primary repair. Group 2; Hyaluronic acid group: the site of anastomosis was coated by hyaluronic acid after primary repair. Group 3; Primary repair only was done. Results: 100% of cases in group 1 and group 2 showed satisfactory wound healing and 83.3% in group3 showed satisfactory wound healing with no significant difference between them. Conclusion: There was an increase in the number of regenerated nerve fibers in the corticosteroids and hyaluronic acid especially on the distal end in comparison to the control group

    Outcome of Dome-Shaped Proximal Tibial Osteotomy in Infantile Genu Varum

    Get PDF
    Background: The goals of the proximal tibial osteotomy are correcting the deformity, Hip-knee-ankle angle, and preventing the progress of the destruction of the medial compartment of the knee joint.Objectives: The aim of the work was to evaluate the outcome of children with genu varum after proximal tibial dome shaped osteotomy.Patients and Methods: These randomized clinical trials study included a total of 10 patients with 12 affected knees confirmed with persistent physiologic genu varum, attending at Orthopedic Department, Zagazig University Hospitals, Zagazig, Egypt. All cases were evaluated pre and post-operatively according to Modified Hospital for Special Surgery Knee Scoring System (HSSKS) as shown in appendix I. cases were assessed for functional improvement after surgery at 2, 4 months and detection of malunion or delayed union after 3 months. Results: The mean (±SD) pre-operative tibio-femoral angle was 21.7 (±5.6) versus 3.18 (±1.97) post-operatively, preoperative femoral condyle-tibial shaft angle (FTA) was 16.3 (± 2.8) versus 3.2 (±1.1) post-operatively and preoperative metaphyseal diaphyseal angle was 15.8 (±2.6) versus 3.6 (±1.2) post-operatively with a statistically significant difference in between (p < 0.05). The mean pre-operative HSSKS scores were 70.16±11.3 while the mean post-operative HSSKS scores were 91.4±2.1.Conclusion: It could be concluded that proximal tibial osteotomy using dome-shaped procedure to correct Infantile Genu varum deformity, has favorable treatment outcomes, does not involve any dangerous complications, and can be used as a safe and effective treatment method for the correction of infantile genu varum deformity. In the current study, angles significantly improved, most of legs got full correction and little complications occurred

    Enhanced Water Electrolysis: Effect Of Temperature On The Oxygen Evolution Reaction At Cobalt Oxide Nanoparticles Modified Glassy Carbon Electrodes

    Get PDF
    Water splitting producing hydrogen and oxygen gases appears promising in view of the increasing need of renewable energy sources and storage strategies. Investigation of stable and highly efficient electrocatalysts for oxygen evolution reaction (OER) is targeted in this study at cobalt oxide nanoparticle modified glassy carbon (nano-CoOx/GC) electrodes. The effect of the preparation (Tp) and measuring temperature (Tm) on the electrocatalytic activity of nano-CoOx/GC towards the OER is investigated under various operating conditions. Linear sweep voltammetry (LSV), cyclic voltammetry (CV) as well as SEM and XRD techniques were used to probe the electrocatalytic and morphological characteristics of nano-CoOx prepared under various conditions. Increasing Tp and/or Tm results in improving the kinetics and electrocatalytic activity of the proposed anodes towards the OER as demonstrated in the value of the onset potential of the OER and the OER currents recorded at a fixed potential. The morphology as well as the surface characterization of the prepared catalyst are reported herein and evaluated

    Spectrophotometric Determination of Omeprazole Sodium and Ranitidine Hydrochloride Using 2, 4-dinitrofluorobenzene and 4- chloro-7-nitrobenzen-2-oxa-1, 3-diazole Accompanied with a Kinetic Study

    Get PDF
    Two accurate, simple and sensitive spectrophotometric methods were developed for determination of omeprazole sodium and ranitidine hydrochloride in bulk and pharmaceutical dosage forms. The first method was based on the reaction of these drugs with 2, 4- dinitrofluorobenzene producing yellow colored products measured at λmax 470 nm and 420 nm for omeprazole sodium and ranitidine HCl, respectively. Beer’s law was obeyed in the concentration range from (5-40 µg.ml-1) for omeprazole sodium and (30-180 µg.ml-1) for ranitidine HCl with molar absorpitivity 9.202 x 103 Lmol-1cm-1 and 1.778 x 103 Lmol-1cm-1, respectively. The second method was based on the reaction of omeprazole sodium and ranitidine HCl with 4- Chloro-7-nitrobenzen-2-oxa-1, 3-diazole producing yellow colored adducts measured at λmax 481 nm and 468 nm for omeprazole sodium and ranitidine HCl, respectively. This method was accompanied with a kinetic study for ranitidine HCl. The absorbance-concentration plots were rectilinear over concentration range (2-12 µg.ml-1) and (0.025-0.15 µg.ml-1) for omeprazole sodium and ranitidine HCl with molar absorpitivity 4.062 x 104 Lmol-1cm-1 and 2.802 x 106 Lmol-1cm-1, respectively. These methods hold their accuracy and precision well when applied to the determination of omeprazole sodium and ranitidine HCl in their dosage forms

    MANAGEMENT’S PERCEPTION OF STOCK DIVIDEND DISTRIBUTION IN AN EMERGING CAPITAL MARKET: THE CASE OF KUWAIT

    Get PDF
    The purpose of this study is to investigate perceptions of top managers of Kuwaiti companies regarding factors the affect their companies’ decision to distribute stock dividend ( SD ). A questionnaire listing 32 reasons that could explain companies’ decisions to declare SDs was distributed to a sample of 120 randomly selected top managers from 100 Kuwaiti companies and 73 responses were received (representing a 61% response rate ). Participants were classified according to: ( 1 )business sector ( investment, real estate, banking, service, and industrial ) and ( 2 ) size of SDs ( small ( less than 25% ) and large ( 25% or more )). Nonparametric statistical tests were employed to analyze the data.Stock Dividends, Importance Ratings, Trading Liquidity, Institutional Investors

    Synthesis, spectroscopic and thermal characterization of Fe(III)-mixed ligand complexes and spectrophotometric determination of Fe(III) in various samples

    Get PDF
    The aim of the present study is to find a non time consuming, economical and reliable spectrophotometric procedures using commercially available spectrophotometric reagents for the determination of Fe(III) ions. The methods are based on the formation of colored ternary complexes using, 1,10-phenanthroline and eriochrome black T or tartrazine mixed reagents and improved using a cationic surfactant, cetyltrimethyl ammonium bromide. This surfactant interacts with the complex to build up true ternary complex. The most suitable conditions for determination of Fe(III) ions and the parameters affecting the reactions including pH, time, temperature, stoichiometric ratios and reagents concentrations are optimized. The effect of different interfering ions is studied together with the suitable masking agents. The developed methods are used for the determination of Fe(III) ions in the presence of cetyltrimethyl ammonium bromide in different types of water (polluted industrial waste, ground, river Nile and drinking water). The synthesis and spectroscopy studies of two Fe complexes were reported. Thermal analysis was carried out in order to give an idea about the thermal stability of the complexes

    Surgical management of fracture both bone forearm in pediatric using elastic stable intramedullary nail

    Get PDF
    Background: In children, forearm fractures are among the most prevalent types of fractures Operative procedures such as, pinning with K-wires, plate osteosynthesis as well as elastic-stable intramedullary nailing (ESIN) are necessary for these fractures.Objective: This study aimed to assess treating and outcomes of pediatric forearm fractures with elastic stable intramedullary nailing (ESIN).Patients and methods: At Orthopedic Departments of Zagazig University Hospital and Tripoli University Hospital, 8 skeletally immature patients with diaphyseal forearm fractures were studied in prospective cohort research. The study was carried out from November 2020 to May 2021. Pre-operative X-ray and CT were done and the patient was prepared for surgery. Elastic-stable intramedullary nailing technique was done to all patients, all patients were regularly followed clinically and radiographically for 1 week and then 2, 4, 6, 12 week after end of surgery.Results: we found that all patients progressed to union without the need for any further surgical intervention with good functional outcome as regards forearm rotation. One case had residual radius angulation more than 20 degree, no case had residual ulna angulation, 2 cases had superficial infection, 1 case had superficial radial nerve palsy and 1 case had elbow joint stiffness.Conclusion: Intramedullary fixation by flexible intramedullary nails (ESIN) is successful treatment option and recommended for pediatric patients with 4-14 years of age or older because it is simple safe and minimally invasive procedure and effective method of treatment that provides many biological and mechanical advantages
    corecore