295 research outputs found

    Comparative analysis of diagnostic applications of autoscan tools on vehicle systems

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    The study was carried out in five institutions where motor vehicle mechanics trade is offered as automobile technology which includes, three centers where auto scan tools are used for vehicle repairs and two technical colleges in Enugu state that offer motor vehicle mechanics (MVM) trade. A total of 83 MVM trainers, teachers and instructors comprise the population for the study. Five research questions were raised and three null hypotheses tested at 0.05and 0.01 significance levels guided the study. A structured questionnaire with 3 items questions as checklist, 2 Auto scan tools were used for the study and test carried out on 5 vehicle systems at the 3 centers where Innova 1360B with snap shoot (AST1) was compared with Innova 1360B without snap shoot (AST2) were used for vehicle diagnosis. The instrument was validated by five experts and modifications were made in the instrument according to their recommendations. Analysis of variance (ANOVA) of a two- way classification experiment data with two observations per experimental unit was used for the evaluation. The results revealed that the efficiencies of AST1 and AST2 in performing the diagnosis because at 1% level of significance, the F-cal was 0.04 and F-tab was 8.65 but differ in performances on various vehicle systems because at 1% level of significance, the F-cal was 7.38 and F-tab was 7.01.Key words: vehicle systems, auto scan - tool, diagnostic application, comparative analysis, evaluation

    Potentials of Momordica angustisepala fiber in enhancing strengths of normal portland cement concrete

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    Presence of cracks in concrete affect the integrity. It reduces the life expectancy of concrete structures and is often responsible for collapse of structures, especially in the developing nations. At the root of these cracks is the very low tensile strength of concrete. Various techniques have been suggested for the enhancing the tensile strength, among which is the use of discontinuous micro fibers of various nature. This research investigated the use of Momordica angustisepala (Ma) fiber to enhance concrete strength. Concrete containing coconut fiber was adopted as a control. Slump test, air entrainment test, compression test and split tensile test were carried out on specimens. Results of the research indicate that an optimum Momordica angustisepala fiber contents of 0.25 and 0.5% enhanced respectively the compressive strength by 4.37% and the tensile strength by 10%. The results clearly show that this renewable material has the potential to enhance the compressive and tensile strengths of concrete

    Accessment of the Kidney in Ginger Treated Wistar Rats

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    Ginger, botanically known as Zingerber offinale is an underground stem or rhizome which is known to have originated from Asia and have been reported to have a number of medicinal properties which is used in the treatment of many ailments such as arthritis, painful menstrual periods, nausea etc. It is also used as a common specie in food and bakery industries. The effect of ethanolic extract of ginger on the kidney of male wistar rats was studied due to the availability and medicinal uses of ginger. Twenty five (25) adult Wistar rats weighing 125-200g were divided into five groups. Group A animals served as the control and were served with distilled water , B served as vehicle control groups and received olive oil.  The animals in groups C, D and E served as experimental groups, and received 100mg/kg, 250mg/kg and 500mg/kg body weight of the ethanolic extract of Zingiber officinale respectively. The animals received the extract for 14 days and were sacrificed 24 hours after the last administration and the kidney was routinely processed histologically. The study shows enlargement of Bowman’s space, disintegration of glomerular cells and dilation of the tubular lumen with shrinkage of tubular luminal cells when compared to the control group, which progressively increased as the duration of intake of Zinger officinlae increased. Therefore, Zingerber officinale should be used with caution because it may have deleterious effects on the liver cells at high doses. Keywords: Assessment, Ginger, Treatment, Kidney, Wistar ra

    PREDICTION OF FRESH AND HARDENED PROPERTIES OF NORMAL CONCRETE VIA CHOICE OF AGGREGATE SIZES, CONCRETE MIX-RATIOS AND CEMENT

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    Concrete is the most commonly used building material for building most of the world’s buildings and infrastructure. After centuries of usage, it still remains the most widely adopted construction material worldwide. But in many developing nations, the frequent occurrence of building collapse has been mostly ascribed to poor quality concrete. As Nigeria is noted for frequent building collapse, this research reproduces standard concrete practices commonly adopted in Nigerian construction industry with the intent to predict design strength via choice of coarse aggregate sizes ( 12.5 mm, 19 mm, 30 mm and mixed), concrete mix-ratios (1:2:4, 1:3:6, 1:2:3) and ordinary Portland cement types (42.5R and 32.5N). Cement compound’s composition tests, fresh property tests and hardened property tests were conducted on samples. Test results from building cites of different Local Government Areas of Lagos State, Nigeria obtained in 2010 are compared with the compressive test results of this research via statistical tools. Results indicate that the fresh properties and hardened properties are influenced in a proportional manner by the sizes of aggregates and that the choices of aggregate sizes, concrete mix-ratios and cement types can be used to predict the fresh and hardened properties of normal concrete. This study also show that poor concrete production is one of the principal cause of frequent building collapse in Nigeria

    Heterotropic pregnancy: a common masquerade than ever thought?

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    Heterotopic pregnancy, coexistence of living or dead intrauterine pregnancy, single or multiple, with extra-uterine pregnancy located in the oviduct, ovary, uterine cornua, cervix or rarely peritoneal cavity. Heterotropic pregnancy is relatively uncommon in spontaneous conception with 1 in 30,000 cases reported, the incidence of heterotopic pregnancy increases to 1 in 3900 when conception is enhanced with various assisted reproduction techniques (ART). It is an ectopic pregnancy coexisting with intrauterine pregnancy. But is the incidence of heterotropic pregnancy rising? A case was reported from our centre in 2018 by Ejikeme et al, and we have recorded another two cases in the period of one year. Ectopic pregnancy has been described as a great masquerader, which makes diagnosis and management of heterotropic pregnancy a dilemma to attending physician. We present a case of an unbooked 26 years old G4P3+0 who has no family history of multiple gestation and presented at gestational age of 8 weeks and 5 days with 2 days history of abdominal pain and vaginal bleeding and 2 hours history of loss of consciousness. She later had exploratory laparotomy with left salpingectomy and manual vacuum aspiration of Retained Products of Conception with good outcome. In conclusion, spontaneous heterotropic pregnancy is a rare occurrence, however with advent of artificial reproductive technology and increase incidence of pelvic inflammatory disease, the incidence could be higher than earlier suspected

    The trend of collapse of buildings in concrete materials in Lagos State, Nigeria (2013-2019)

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    t. In recent times, efforts are channeled towards limiting the impact of waste plastic pollution on the environment. This study examines the beneficial utilization of polyethylene terephthalate (PET) wastes, which is a non-biodegradable waste materials as a partial substitute for sand in the production of non-load bearing hollow sandcrete blocks. The physical and mechanical properties such as density and compressive strength of the hollow sandcrete blocks using PET waste as a replacement for fine aggregate at 5%, 10%, 30% and 50% were determined. Tests results show that the density of the produced sandcrete blocks decreases as the waste PET content increases. Results showed that the density varied from 1391.33 kg/m3 for 50%PET content to 1954.54 kg/m3 for 5%PET content, while the density of the reference sandcrete was 2002.15 kg/m3 for 7 days. The values of densities ranged between 1453.88 kg/m3 for PET 50% and 1851.09 kg/m3 for PET 5% and the density of reference sandcrete was 1991.77 kg/m3 at 28 days. The sandcrete blocks also demonstrate a similar reduction trend in compressive strength as the PET content increases. The compressive strength ranged between 1.140 N/mm2 for 50%PET and 2.564 N/mm2 for 5%PET content and 1.510 N/mm2 for 50%PET to 2.991 N/mm2 for 5%PET respectively, as the curing age increases from 7 to 28 days. The hollow sandcrete block containing an optimum 5% replacement percentage of sand with PET waste showed comparable strength to the conventional sandcrete blocks. This will help to mitigate the menace of marine plastic pollution and promote responsible consumption

    Tracking Membrane Protein Association in Model Membranes

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    Membrane proteins are essential in the exchange processes of cells. In spite of great breakthrough in soluble proteins studies, membrane proteins structures, functions and interactions are still a challenge because of the difficulties related to their hydrophobic properties. Most of the experiments are performed with detergent-solubilized membrane proteins. However widely used micellar systems are far from the biological two-dimensions membrane. The development of new biomimetic membrane systems is fundamental to tackle this issue

    DAAM is required for thin filament formation and Sarcomerogenesis during muscle development in Drosophila.

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    During muscle development, myosin and actin containing filaments assemble into the highly organized sarcomeric structure critical for muscle function. Although sarcomerogenesis clearly involves the de novo formation of actin filaments, this process remained poorly understood. Here we show that mouse and Drosophila members of the DAAM formin family are sarcomere-associated actin assembly factors enriched at the Z-disc and M-band. Analysis of dDAAM mutants revealed a pivotal role in myofibrillogenesis of larval somatic muscles, indirect flight muscles and the heart. We found that loss of dDAAM function results in multiple defects in sarcomere development including thin and thick filament disorganization, Z-disc and M-band formation, and a near complete absence of the myofibrillar lattice. Collectively, our data suggest that dDAAM is required for the initial assembly of thin filaments, and subsequently it promotes filament elongation by assembling short actin polymers that anneal to the pointed end of the growing filaments, and by antagonizing the capping protein Tropomodulin

    Multifrequency studies of the peculiar quasar 4C+21.35 during the 2010 flaring activity

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    The discovery of rapidly variable Very High Energy ( VHE; E &gt; 100 GeV). - ray emission from 4C + 21.35 ( PKS 1222+ 216) by MAGIC on 2010 June 17, triggered by the high activity detected by the Fermi Large Area Telescope ( LAT) in high energy ( HE; E &gt; 100 MeV). - rays, poses intriguing questions on the location of the. - ray emitting region in this flat spectrum radio quasar. We present multifrequency data of 4C + 21.35 collected from centimeter to VHE during 2010 to investigate the properties of this source and discuss a possible emission model. The first hint of detection at VHE was observed by MAGIC on 2010 May 3, soon after a gamma- ray flare detected by Fermi-LAT that peaked on April 29. The same emission mechanism may therefore be responsible for both the HE and VHE emission during the 2010 flaring episodes. Two optical peaks were detected on 2010 April 20 and June 30, close in time but not simultaneous with the two gamma- ray peaks, while no clear connection was observed between the X-ray and gamma- ray emission. An increasing flux density was observed in radio and mm bands from the beginning of 2009, in accordance with the increasing gamma- ray activity observed by Fermi-LAT, and peaking on 2011 January 27 in the mm regime ( 230 GHz). We model the spectral energy distributions ( SEDs) of 4C + 21.35 for the two periods of the VHE detection and a quiescent state, using a one-zone model with the emission coming from a very compact region outside the broad line region. The three SEDs can be fit with a combination of synchrotron self-Compton and external Compton emission of seed photons from a dust torus, changing only the electron distribution parameters between the epochs. The fit of the optical/UV part of the spectrum for 2010 April 29 seems to favor an inner disk radius of &lt; six gravitational radii, as one would expect from a prograde-rotating Kerr black hole.</p
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