392 research outputs found

    Fascioliasis in Cattle and Goat Slaughtered at Calabar Abattoirs

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    The occurrence of fascioliasis among trade ruminants (cattle and goat) slaughtered at Calabar abattoirs was investigated using centrifugal method, haemocytometer and histological preparations for fecal, blood and liver tissue examinations respectively. One hundred and seventy nine (44.8%) of 400 cattle and 126 (36.0%) of 350 goat respectively had fascioliasis. Parasite intensity ranged between 8 - 10 flukes per liver of infected cattle and 4 - 5 flukes per liver of infected goat. Infected liver of the two ruminants were damaged. Damaged Hepatic parenchyma resulting in severe haemorrhage, thickening and gross fibrosis of bile duct were observed. Dislodge hepatic cells became wandering cells amidst macrophages within the sinusoid. The central vein of cattle infected by Fasciola hepatica and Fasciola gigantica was enlarged and laden with debris resulting in obstruction of liver function such as protein synthesis. This caused the liver to be rejected. Seven to seventeen percent of infected cattle liver and2 – 7% of infected goat liver were discarded. Excessive leucocytosis with marked eosinophilia was observed in infected animal blood. It is important to examine carcasses of ruminants slaughtered in abattoirs before presentation for public consumption

    Literal Level of Student's Comprehension in Nigeria: A Means for Growing a New Generation African Scholars

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    The concern of this study was to examine students’ attainment in literal level of reading comprehension under reading for exact meaning, for information and for gist in a text. Two research questions and two hypotheses were formulated to guide in the study. An expost-facto research design was also employed. The researcher used an adapted Literal Reading Comprehension Test (LRCAT) for data collection. Out of a population of 1,803 SS2 students in Uyo L.G.A, 109 students formed the sample by  a stratified and  a hart and draw simple random sampling technique. Data collected were analyzed using the mean, standard deviation and paired dependent t-test.The mean score of students in reading for exact meaning was higher than reading for information and gist. The major findings were that with a df of 108 there is significant difference in students’ mean attainment scores in reading for exact meaning and reading for information. Also, there is significant difference in students’ mean attainment scores of reading for exact meaning and reading for gist. Based on the findings, it was recommended among others that, learners should consciously be taught how to develop their literal reading comprehension in order to encourage the acquisition of other comprehension levels at the senior secondary level, if  comprehension must have been attained. Keywords: Literal Reading Comprehension, Reading for Gist, Reading for Informatio

    K+ΛK^+\Lambda and K+Σ0K^+\Sigma^0 photoproduction with fine center-of-mass energy resolution

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    Measurements of γpK+Λ\gamma p \rightarrow K^{+} \Lambda and γpK+Σ0\gamma p \rightarrow K^{+} \Sigma^0 cross-sections have been obtained with the photon tagging facility and the Crystal Ball calorimeter at MAMI-C. The measurement uses a novel K+K^+ meson identification technique in which the weak decay products are characterized using the energy and timing characteristics of the energy deposit in the calorimeter, a method that has the potential to be applied at many other facilities. The fine center-of-mass energy (WW) resolution and statistical accuracy of the new data results in a significant impact on partial wave analyses aiming to better establish the excitation spectrum of the nucleon. The new analyses disfavor a strong role for quark-diquark dynamics in the nucleon.Comment: 7 pages, 8 figure

    Lack of confidence among trainee doctors in the management of diabetes: the Trainees Own Perception of Delivery of Care (TOPDOC) Diabetes Study

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    Background: There is an increased prevalence of diabetes. Doctors in training, irrespective of specialty, will have patients with diabetes under their care

    Emerging challenges in innate immunity: Staphylococcus aureus and healthcare-associated infection

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    Staphylococcus aureus, a prominent human pathogen, exhibits a remarkable ability to interact with host proteins involved in crucial physiological pathways, such as the complement system, coagulation cascade, and fibrinolysis cascade. This paper explores the ability of this notable bacteria to successfully manipulate and evade the host innate system, expatiating on the strategies that enhance its pathogenicity leading to implications on the healthcare system such as the propagation of diverse nosocomial infections. The investigation focuses on key S. aureus proteins, including Coagulase (Coa), von Willebrand factor-binding protein (vWbp), and Staphylokinase (SAK), which play pivotal roles in blood coagulation, fibrinolysis, and evasion of host antibacterial peptides. Notably, these proteins contribute to the formation of fibrin networks, protecting the bacterium from immune clearance and promoting lethal bloodstream infections in murine models. Additionally, the debate surrounding the role of SAK as a critical virulence factor is addressed, emphasizing its impact on biofilm formation, invasion of internal organs, and bacterial loads in sepsis studies. Furthermore, the interaction of S. aureus with matrix metalloproteinases and the secretion of superantigen-like proteins (SSL1 and SSL5) are explored as additional mechanisms employed by the bacterium to impede immune responses. In addressing emerging challenges in innate immunity, the paper discusses the escalating antibiotic resistance in S. aureus, with a specific focus on methicillin-resistant strains (MRSA) and its capacity to instigate healthcare-associated infections as an effect

    Measurement of the beam-helicity asymmetry II^{\odot} in the photoproduction of π0π±\pi^0\pi^{\pm}-pairs off protons and off neutrons

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    Beam-helicity asymmetries have been measured at the MAMI accelerator in Mainz for the photoproduction of mixed-charge pion pairs in the reactions γpnπ0π+\boldsymbol{\gamma}p\rightarrow n\pi^0\pi^+ off free protons and γd(p)pπ0π\boldsymbol{\gamma}d\rightarrow (p)p\pi^0\pi^- and γd(n)nπ0π+\boldsymbol{\gamma}d\rightarrow (n)n\pi^0\pi^+ off quasi-free nucleons bound in the deuteron for incident photon energies up to 1.4 GeV. Circularly polarized photons were produced from bremsstrahlung of longitudinally polarized electrons and tagged with the Glasgow-Mainz magnetic spectrometer. The charged pions, recoil protons, recoil neutrons, and decay photons from π0\pi^0 mesons were detected in the 4π\pi electromagnetic calorimeter composed of the Crystal Ball and TAPS detectors. Using a complete kinematic reconstruction of the final state, excellent agreement was found between the results for free and quasi-free protons, suggesting that the quasi-free neutron results are also a close approximation of the free-neutron asymmetries. A comparison of the results to the predictions of the Two-Pion-MAID reaction model shows that the reaction mechanisms are still not well understood, in particular at low incident photon energies in the second nucleon-resonance region.Comment: accepted for publication in Eur. phys. J.

    Quasifree photoproduction of η\eta mesons off protons and neutrons

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    Differential and total cross sections for the quasifree reactions γpηp\gamma p\rightarrow\eta p and γnηn\gamma n\rightarrow\eta n have been determined at the MAMI-C electron accelerator using a liquid deuterium target. Photons were produced via bremsstrahlung from the 1.5 GeV incident electron beam and energy-tagged with the Glasgow photon tagger. Decay photons of the neutral decay modes η2γ\eta\rightarrow 2\gamma and η3π06γ\eta\rightarrow 3\pi^0 \rightarrow 6\gamma and coincident recoil nucleons were detected in a combined setup of the Crystal Ball and the TAPS calorimeters. The η\eta-production cross sections were measured in coincidence with recoil protons, recoil neutrons, and in an inclusive mode without a condition on recoil nucleons, which allowed a check of the internal consistency of the data. The effects from nuclear Fermi motion were removed by a kinematic reconstruction of the final-state invariant mass and possible nuclear effects on the quasifree cross section were investigated by a comparison of free and quasifree proton data. The results, which represent a significant improvement in statistical quality compared to previous measurements, agree with the known neutron-to-proton cross-section ratio in the peak of the S11(1535)S_{11}(1535) resonance and confirm a peak in the neutron cross section, which is absent for the proton, at a center-of-mass energy W=(1670±5)W = (1670\pm 5) MeV with an intrinsic width of Γ30\Gamma\approx 30 MeV

    Measurements of 12C(→γ,pp) photon asymmetries for Eγ= 200–450 MeV

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    The 12C (→γ ,pp) reaction has been studied in the photon energy range 200-450 MeV at the Mainz microtron MAMI-C, where linearly polarised photons were energy-tagged using the Glasgow-Mainz Tagged Photon Spectrometer and protons were detected in the Crystal Ball detector. The photon asymmetry Σ has been measured over a wider Eγ range than previous measurements. The strongest asymmetries were found at low missing energies where direct emission of nucleon pairs is expected. Cuts on the difference in azimuthal angles of the two ejected protons increased the magnitude of the observed asymmetries. At low missing energies the Σ data exhibit a strong angular dependence, similar to deuteron photodisintegration

    Photoproduction of pi0-mesons off neutrons in the nucleon resonance region

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    Precise angular distributions have been measured for the first time for the photoproduction of π0\pi^{0}-mesons off neutrons bound in the deuteron. The effects from nuclear Fermi motion have been eliminated by a complete kinematic reconstruction of the final state. The influence of final-state-interaction effects has been estimated by a comparison of the reaction cross section for quasi-free protons bound in the deuteron to the results for free protons and then applied as a correction to the quasi-free neutron data. The experiment was performed at the tagged photon facility of the Mainz Microtron MAMI with the Crystal Ball and TAPS detector setup for incident photon energies between 0.450.45~GeV and 1.41.4~GeV. The results are compared to the predictions from reaction models and partial-wave analyses based on data from other isospin channels. The model predictions show large discrepancies among each other and the present data will provide much tighter constraints. This is demonstrated by the results of a new analysis in the framework of the Bonn-Gatchina coupled-channel analysis which included the present data.Comment: accepted for publication in Phys; Rev. Let

    Quasi-free photoproduction of η-mesons off 3He nuclei

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    Quasi-free photoproduction of η-mesons has been measured off nucleons bound in 3He nuclei for incident photon energies from the threshold region up to 1.4 GeV. The experiment was performed at the tagged photon facility of the Mainz MAMI accelerator with an almost 4π covering electromagnetic calorimeter, combining the TAPS and Crystal Ball detectors. The η-mesons were detected in coincidence with the recoil nucleons. This allowed a comparison of the production cross section off quasi-free protons and quasi-free neutrons and a full kinematic reconstruction of the final state, eliminating effects from nuclear Fermi motion. In the S11(1535) resonance peak, the data agree with the neutron/proton cross section ratio extracted from measurements with deuteron targets. More importantly, the prominent structure observed in photoproduction off quasi-free neutrons bound in the deuteron is also clearly observed. Its parameters (width, strength) are consistent with the expectations from the deuteron results. On an absolute scale the cross sections for both quasi-free protons and neutrons are suppressed with respect to the deuteron target pointing to significant nuclear final-state interaction effects
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