65,873 research outputs found

    Prospects of Islamophobia in Nigeria and its Dangers

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    Irrational fear for and prejudice against Islam and its adherents, which is known as Islamophobia has been ravaging many western countries and there appear to be sinister pointers to same in Nigeria. The possibility and risks of a full-blown Islamophobia in Nigeria remains of concern. The origin of Islamophobia in some western countries is linked to violence and terrorism carried out by people who are professedly Muslims. When such incidents are juxtaposed with the state of affairs in Nigeria and counter-violence on Muslims in some quarters, it becomes glaring that Islamophobia is a time bomb waiting to explode in Nigeria. It is however established that those that execute these violence actually do grave harm to the reputation of the Islamic religion which is an essentially religion of peace and are in fact defamers of Islam. The consequences of Islamophobia in Nigeria as elsewhere are grossly undesirable and despicable. But this requires an urgent call to action to avert this impending psychological complex. To live beyond this fear, therefore is the need to intensify vocal denouncement of terrorism by non-Islamic and Islamic leaders, a guarantee of good governance, proper and modest hermeneutics of the Islamic scripture, intra and inter-religious dialogue and collaboration in fighting terrorism and religious violence as panaceas to this imminent plague called Islamophobia

    The influence of a high power diode laser (HPDL) generated glaze on the wetting characteristics and the subsequent HPDL enamelling of ordinary Portland cement

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    High power diode laser (HPDL) surface glazing of the ordinary Portland cement (OPC) surface of concrete was found to effect significant changes in the wettability characteristics of the OPC. This behaviour was identified as being primarily due to: (i) the polar component of the OPC surface energy increasing after HPDL glazing from 3.46 to 15.56 mJm-2, (ii) the surface roughness of the OPC decreasing from an Ra value of 21.91 to 2.88 m after HPDL glazing and (iii) the relative surface O2 content of the OPC increasing by 4.5at% after HPDL glazing. HPDL glazing was consequently identified as occasioning a decrease in the enamel contact angle from an initial value of 1090 to 310, thus allowing the vitreous enamel to wet the OPC surface

    Armament and disarmament in Nigeria: juxtaposing Niger-delta militancy and boko haram insurgency in northern Nigeria

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    Armed conflicts have continued to bedevil Nigeria and account for innumerable loss of lives and properties. The volume of both legally and illegally possessed arms in Nigeria is alarming. They serve as motivation for conflicts and are used to perpetuate them. It appears that arms held by the military and especially civilians in Nigeria have continued to increase exponentially and are often times used indiscriminately. However, in as much as proportionate arms are sine quanon for a nation’s defense as a last resort, its availability to civilians who use them for criminal activities spell doom for any nation. Hence, drawing from scholarly publications and internet works, this study looks at armament and disarmament in Nigeria. It also juxtaposes Niger Delta militancy/disarmament and Boko Haram insurgence in Northern Nigeria, baring their similarities and differences. Borrowing a leaf from the relative success of Niger Delta amnesty/disarmament and considering the obstinate character of Boko Haram insurgents, this study advocates for a similar strategy of disarmament for Boko Haram. This of course, will not be without cumbersome challenges. Therefore, this paper makes recommendations that are believed to be helpful in carrying out this task. That way, arms will be controlled in Nigeria; there will be less armed conflict and colossal loss as a result of armed conflicts

    Young and middle age pulsar light-curve morphology: Comparison of Fermi observations with gamma-ray and radio emission geometries

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    Thanks to the huge amount of gamma-ray pulsar photons collected by the Fermi Large Area Telescope since June 2008, it is now possible to constrain gamma-ray geometrical models by comparing simulated and observed light-curve morphological characteristics. We assumed vacuum-retarded dipole pulsar magnetic field and tested simulated and observed morphological light-curve characteristics in the framework of two pole emission geometries, Polar Cap (PC), radio, and Slot Gap (SG), and Outer Gap (OG)/One Pole Caustic (OPC) emission geometries. We compared simulated and observed/estimated light-curve morphological parameters as a function of observable and non-observable pulsar parameters. The PC model gives the poorest description of the LAT pulsar light-curve morphology. The OPC best explains both the observed gamma-ray peak multiplicity and shape classes. The OPC and SG models describe the observed gamma-ray peak-separation distribution for low- and high-peak separations, respectively. This suggests that the OPC geometry best explains the single-peak structure but does not manage to describe the widely separated peaks predicted in the framework of the SG model as the emission from the two magnetic hemispheres. The OPC radio-lag distribution shows higher agreement with observations suggesting that assuming polar radio emission, the gamma-ray emission regions are likely to be located in the outer magnetosphere. The larger agreement between simulated and LAT estimations in the framework of the OPC suggests that the OPC model best predicts the observed variety of profile shapes. The larger agreement between observations and the OPC model jointly with the need to explain the abundant 0.5 separated peaks with two-pole emission geometries, calls for thin OPC gaps to explain the single-peak geometry but highlights the need of two-pole caustic emission geometry to explain widely separated peaks.Comment: 28 pages, 20 figures, 8 tables; accepted for publication in Astronomy and Astrophysic

    The wear characteristics of a high power diode laser generated glaze on the ordinary Portland cement surface of concrete

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    The ordinary Portland cement (OPC) surface layer of concrete, which was glazed using a high power diode laser (HPDL), has been tested in order to determine the wear characteristics of the glaze. The work showed that the generation of a surface glaze resulted in the considerable enhancement of the wear characteristics over an untreated OPC surface of concrete. Within both normal and corrosive (detergent, NaOH and HNO3) environmental conditions the wear rate of the HPDL generated glaze was 3.5 mg.cm-2.h-1. In contrast, the untreated OPC surface of concrete exhibited a wear rate of 9.8 - 114.8 mg.cm-2.h-1 when exposed to the various reagents. Life assessment testing revealed that the laser glazed OPC surfaces effected an increase in actual wear life of 1.3 to 17.7 times over the untreated OPC surface of concrete, depending upon the corrosive environment. The reasons for these marked improvements in the wear resistance and wear life of the HPDL generated glaze over the untreated OPC surface of concrete can be attributed to firstly, the vitrification of the OPC surface after HPDL treatment which subsequently created a much more dense and consolidated surface, and secondly, the generation of a surface with improved microstructure and phase which is more resistant in corrosive environments

    Identification of the principal elements governing the wettability characteristics of ordinary Portland cement following high power diode laser surface treatment

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    The elements governing modifications to the wettability characteristics of ordinary Portland cement (OPC) following high power diode laser (HPDL) surface treatment have been identified. Changes in the contact angle, , and hence the wettability characteristics of the OPC after HPDL treatment were attributed to: reductions in the surface roughness of the OPC; the increase in the surface O2 content of the ceramic and the increase in the polar component of the surface energy, . What is more, the degree of influence exerted by each element has been qualitatively ascertained and was found to differ markedly. Surface energy, by way of microstructural changes, was found to be by far the most predominant element governing the wetting characteristics of the OPC. To a much lesser extent, surface O2 content, by way of process gas, was also seen to influence to a changes in the wettability characteristics of the OPC, whilst surface roughness was found to play a minor role in inducing changes in the wettability characteristics

    High power diode laser surface glazing of concrete

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    This present work describes the utilisation of the relatively novel high power diode laser (HPDL) to generate a surface glaze on the ordinary Portland cement (OPC) surface of concrete. The value of such an investigation would be to facilitate the hitherto impossible task of generating a durable and long-lasting surface seal on the concrete, thereby extending the life and applications base of the concrete. The basic process phenomena are investigated and the laser effects in terms of glaze morphology, composition and microstructure are presented. Also, the resultant heat affects are analysed and described, as well as the effects of the shield gases, O2 and Ar, during laser processing. HPDL glazing of OPC was successfully demonstrated with power densities as low as 750 W cm-2 and at scanning rates up to 480 mm min-1. The work showed that the generation of the surface glaze resulted in improved mechanical and chemical properties over the untreated OPC surface of concrete. Both untreated and HPDL glazed OPC were tested for pull-off strength, rupture strength, water absorption, wear resistance and corrosion resistance. The OPC laser glaze exhibited clear improvements in wear, water sorptivity, and resistance (up to 80% concentration) to nitric acid, sodium hydroxide and detergent. Life assessment testing revealed that the OPC laser glaze had an increase in actual wear life of 1.3 to 14.8 times over the untreated OPC surface of concrete, depending upon the corrosive environment

    Volterra-assisted Optical Phase Conjugation: a Hybrid Optical-Digital Scheme For Fiber Nonlinearity Compensation

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    Mitigation of optical fiber nonlinearity is an active research field in the area of optical communications, due to the resulting marked improvement in transmission performance. Following the resurgence of optical coherent detection, digital nonlinearity compensation (NLC) schemes such as digital backpropagation (DBP) and Volterra equalization have received much attention. Alternatively, optical NLC, and specifically optical phase conjugation (OPC), has been proposed to relax the digital signal processing complexity. In this work, a novel hybrid optical-digital NLC scheme combining OPC and a Volterra equalizer is proposed, termed Volterra-Assisted OPC (VAO). It has a twofold advantage: it overcomes the OPC limitation in asymmetric links and substantially enhances the performance of Volterra equalizers. The proposed scheme is shown to outperform both OPC and Volterra equalization alone by up to 4.2 dB in a 1000 km EDFA-amplified fiber link. Moreover, VAO is also demonstrated to be very robust when applied to long-transmission distances, with a 2.5 dB gain over OPC-only systems at 3000 km. VAO combines the advantages of both optical and digital NLC offering a promising trade-off between performance and complexity for future high-speed optical communication systems

    Trends of oral cavity, oropharyngeal and laryngeal cancer incidence in Scotland (1975 - 2012) - a socioeconomic perspective

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    Aim: To examine current incidence trends (1975–2012) of oral cavity (OCC), oropharyngeal (OPC) and laryngeal cancer in Scotland by socioeconomic status (SES). Methods: We included all diagnosed cases of OCC (C00.3-C00.9, C02-C06 excluding C2.4), OPC (C01, C2.4, C09-C10, C14) and laryngeal cancer (C32) on the Scottish Cancer Registry (1975–2012) and annual midterm population estimates by age, sex, geographic region and SES indices (Carstairs 1991 and Scottish Index of Multiple Deprivation 2009). Age-standardized incidence rates were computed and adjusted Poisson regression rate-ratios (RR) compared subsites by age, sex, region, SES and year of diagnosis. Results: We found 28,217 individuals (19,755 males and 8462 females) diagnosed with head and neck cancer (HNC) over the study period. Between 1975 and 2012, relative to the least deprived areas, those living in the most deprived areas exhibited the highest RR (>double) of OCC, OPC and laryngeal cancer, and an almost dose-like response was observed between SES and HNC incidence. Between 2001 and 2012, this socioeconomic inequality tended to increase over time for OPC and laryngeal cancer but remained relatively unchanged for OCC. Incidence rates increased markedly for OPC, decreased for laryngeal cancer and remained stable for OCC, particularly in the last decade. Males exhibited significantly higher RRs compared to females, and the peak age of incidence of OPC was slightly lower than the other subsites. Conclusion: Contrary to reports that OPC exhibits an inverse socioeconomic profile, Scotland country-level data show that those from the most deprived areas consistently have the highest rates of head and neck cancers
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