Seroprevalence of Hepatitis B Virus and Human Immunodeficiency Virus infection among students in Ahmadu Bello University, Zaria, Nigeria

Hepatitis B virus (HBV) and Human Immunodeficiency Virus (HIV) are endemic in sub-Saharan Africa. Evidence on HBV co-infection rates with HIV infection among individuals remains conflicting. The study was conducted to determine the seroprevalence of HBV and HIV infections and the possible potential risk factors among students of Ahmadu Bello University (ABU), Zaria, Nigeria. Blood samples were collected from 600 consenting consecutive students aged between 16 and 40 years old at the University Health Services, ABU, Zaria. The sera were screened for HBsAg, anti-HBs, HBeAg, anti-HBe and anti-HBc using diagnostic kits and for Human Immunodeficiency Virus using DetermineTMHIV-1/2 kits. Reactive sera for HBsAg were further confirmed using ELISA kits. For HBsAg, 9.2% (55/600) tested positive among which, none had detectable anti-HBs antibodies, indicating recent infection. About 7.3%, 36.4% and 94.5% were positive for HBeAg, anti-HBe and anti-HBc respectively. Seroprevalence of HIV infection was 2.8% (17/600). One (0.2%) of the student was infected with both HBV and HIV. There was a significant association between age group (p=0.016), gender (p=0.049), family history of HBV infection (p=0.000), and seroprevalence of HBsAg. While for HIV, only menial jobs (p = 0.001) was significantly associated with the infection. The results showed close contact among family members to be a predisposing factor to these viral infections. A total of 314 students were ignorant of HBV and four of them were infectious. The seroprevalence of HBsAg obtained in this study indicates high endemicity according to WHO classification. However, seroprevalence of HIV and its co-infection rate with HBV were very low. This was encouraging and it indicates that the campaign on HIV is yielding the desired result. Therefore similar campaign should be extended to Hepatitis B.Keywords: Seroprevalence; HIV; HBsAg; Serological markers; Students; Nigeri

Development of Auto-Notification Application for Mobile Device using Geofencing Technique

Mobile devices have become an integral part of human lifestyle. The convenience offered by mobile devices usage can’t be denied. However, there are growing concerns about the disturbances caused by usage of mobile devices. One of the concerns is the disturbances caused by ringing sound of mobile devices at places that require silence such as mosque, library, cinema, and meeting room. Mobile device owners often forget to turn on silence mode on their devices in these places. To overcome such problem, this paper proposes an auto-notification application for mobile device using geofencing technique. Geofencing technique is used to detect virtual boundary that have been preset around required places. When a user enters the particular place, the application will detect that the user’s mobile device has crossed the virtual boundary and will automatically notify the user to turn the silence mode on the device. The opposite process will happen when the user crosses the boundary to exit the place. The main advantage of the application is that it will remind mobile device users to mute their devices when they are entering places that require silenc

On the insecurity of generalized (Rivest-Shamir-Adleman) - advance and adaptable cryptosystem

This paper explores the security claims of the Generalized (Rivest-Shamir-Adleman) - Advance and Adaptable Cryptosystem, in short the GRSA-AA cryptosystem. In the GRSA-AA design proposal, the public key n is defined as the multiplication of two large prime numbers, while the values of encryption key E and decryption key D are relying on the result of multiplying 2k large prime numbers called N where n divides N. The GRSA-AA claimed that the brute force is necessary to break the cryptosystem even if the integer n was factored. Nevertheless, this paper aims to show that this scheme is insecure once n is factored. The mathematical proof is presented to show that it is easy to generate an alternative value to the private key D without brute-forcing, yet successfully break the system

A study of single and two-plane balancing using influence coefficient method / Wan Sulaiman Wan Mohamad, Ahmad Azlan Mat Isa and M.A Ismail

Unbalance effect on rotating element is a condition resulted from an off centered mass concentration about a rotor s rotating centerline which will then generate centrifugal forces with increasing running speeds. This phenomenon will bring about excessive noise and vibration which in turn causing damages to the rotating elements and its support mechanism. To overcome this problem, a correction is required so as to minimize the excessive vibration as low as possible. In this study, unbalance problems including single and two-plane balancing are studied extensively by using theoretical influence coefficient method followed by the experimental verifications. Experimental procedure is performed by using trial mass to calculate the influence coefficient and the corrected mass values as well as the phase angles. The studies cover the static and dynamics balancing for the single plane and two-plane balancing respectively. Finally, the vibration reduction of the rotor is compared theoretically and experimentally. Based on the results, the improved vibration reduction could be obtained reasonably for both single and two-plane balancing by using influence coefficient method

Sedimentary evidence of the Late Holocene tsunami in the Shetland Islands (UK) at Loch Flugarth, northern Mainland

Tsunami deposits around the North Sea basin are needed to assess the long-term hazard of tsunamis. Here, we present sedimentary evidence of the youngest tsunami on the Shetland Islands from Loch Flugarth, a coastal lake on northern Mainland. Three gravity cores show organic-rich background sedimentation with many sub-centimetre-scale sand layers, reflecting recurring storm overwash and a sediment source limited to the active beach and uppermost subtidal zone. A basal 13-cm-thick sand layer, dated to 426–787 cal. a CE based on 14C, 137Cs and Bayesian age–depth modelling, was found in all cores. High-resolution grain-size analysis identified four normally graded or massive sublayers with inversely graded traction carpets at the base of two sublayers. A thin organic-rich ‘mud’ drape and a ‘mud’ cap cover the two uppermost sublayers, which also contain small rip-up clasts. Grain-size distributions show a difference between the basal sand layer and the coarser and better sorted storm layers above. Multivariate statistical analysis of X-ray fluorescence core scanning data also distinguishes both sand units: Zr, Fe and Ti dominate the thick basal sand, while the thin storm layers are high in K and Si. Enriched Zr and Ti in the basal sand layer, in combination with increased magnetic susceptibility, may be related to higher heavy mineral content reflecting an additional marine sediment source below the storm-wave base that is activated by a tsunami. Based on reinterpretation of chronological data from two different published sites and the chronostratigraphy of the present study, the tsunami seems to date to c. 1400 cal. a BP. Although the source of the tsunami remains unclear, the lack of evidence for this event outside of the Shetland Islands suggests that it had a local source and was smaller than the older Storegga tsunami (8.15 cal. ka BP), which affected most of the North Sea basin.</p

Equilibrium moisture contents for peeled coffee cherry based on static and dynamic methods

The desorption isotherms for 50 and 73 °C and residual mucilage content of 16.1 and 52.7% in Arabica Coffee (Coffea arábica L.), cv Novo Mundo-Acaiá, were built. After this, eight mathematical models (BET, BET Linear, GAB, Halsey, Halsey Modified, Langmuir, Oswin e Peleg) for desorption for hygroscopic products were adjusted to the experimental data for obtaining the coefficients of the models. The choice of the best adjustment was based on the analysis of the following parameters: determination coefficient (R²), relative average deviation, residual distribution tendency and standard deviation of the estimation. The desorption isotherms at 50 °C for cherry coffee with 16.1 and 52.7% residual mucilage contents could be represented by Peleg, Modified Halsey, GAB e Oswin models. At 73 °C the GAB model did not represent the experimental data, and the models of Peleg and Modified Halsey were the best ones. In order to estimate the dynamic equilibrium moisture content, the equation proposed by Fioreze showed to be highly satisfactory.Construíram-se as isotermas de dessorção de grãos da espécie Café Arábica (Coffea arábica L.), da cultivar Novo Mundo-Acaiá, para as temperaturas de 50 e 73 °C e teores de mucilagem residual de 16,1 e 52,7%; posteriormente, oito modelos matemáticos de sorção de produtos higroscópicos foram ajustados aos dados experimentais (BET, BET Linear, GAB, Halsey, Halsey Modificado, Langmuir, Oswin e Peleg), com a finalidade de se obter seus coeficientes. A escolha do melhor ajuste se deu em função da avaliação do coeficiente de determinação (R²), do desvio relativo médio (DRM), da tendência de distribuição dos resíduos provenientes dos ajustes dos modelos e do desvio padrão da estimativa. As isotermas de dessorção para temperatura de 50°C e teores de mucilagem residual de 16,1 e 52,7% podem ser representadas pelos modelos Peleg, Halsey Modificado, GAB e Oswin. Para a temperatura de 73°C, o modelo GAB não representa bem os dados experimentais, sendo que os modelos Peleg e Halsey Modificado indicam o melhor desempenho. Com vistas à estimativa das umidades de equilíbrio dinâmicas, a equação proposta por Fioreze mostrou-se altamente satisfatória.470476Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

ELECTROMYOGRAPHY ANALYSIS ASSOCIATED WITH PROLONGED STANDING IN METAL STAMPING INDUSTRY

Many jobs in metal stamping industry require workers to perform in standing position. Standing is a practical working position when the workers are lifting heavy products, and pushing or pulling excessive loads because those jobs require a stable position and large degree of freedom. However, if the workers perform the jobs continuously in standing throughout the working hours, they may be experience muscle fatigue. The objective of this study such as to measure the myoelectric levels (μV) exerted by the left and right erector spinae, left and right tibialis anterior. The myoelectric levels in the muscles were measured using surface Electromyography (sEMG). Ten production workers from a metal stamping industry participated as subjects for sEMG measurement. Out of which, five workers from metal stamping process lines and another five from handwork section. The muscle activity of the subjects was measured for 5 hours and 45 minutes of continuous standing during beginning of workday, middle of workday, and end of workday from Monday to Wednesday. Results of comparison found that the two groups of workers show significant difference (p-value &lt; 0.05) in myoelectric level in the right erector spinae, right gastrocnemius, and left tibialis anterior during the beginning of workday. However, the two groups of workers did not show any significant difference in myoelectric level during the middle of the workday and end of the workday. It can be concluded that muscle activity of the workers was determined by the work load and duration of standing. This study suggests that anti fatigue mat and micro breaks should be provided to the workers to reduce muscle fatigue

Subcutaneous REGEN-COV Antibody Combination to Prevent Covid-19

BACKGROUND REGEN-COV (previously known as REGN-COV2), a combination of the monoclonal antibodies casirivimab and imdevimab, has been shown to markedly reduce the risk of hospitalization or death among high-risk persons with coronavirus disease 2019 (Covid-19). Whether subcutaneous REGEN-COV prevents severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and subsequent Covid-19 in persons at high risk for infection because of household exposure to a person with SARS-CoV-2 infection is unknown. METHODS We randomly assigned, in a 1:1 ratio, participants (=12 years of age) who were enrolled within 96 hours after a household contact received a diagnosis of SARSCoV- 2 infection to receive a total dose of 1200 mg of REGEN-COV or matching placebo administered by means of subcutaneous injection. At the time of randomization, participants were stratified according to the results of the local diagnostic assay for SARS-CoV-2 and according to age. The primary efficacy end point was the development of symptomatic SARS-CoV-2 infection through day 28 in participants who did not have SARS-CoV-2 infection (as measured by reverse-transcriptase- quantitative polymerase-chain-reaction assay) or previous immunity (seronegativity). RESULTS Symptomatic SARS-CoV-2 infection developed in 11 of 753 participants in the REGEN-COV group (1.5%) and in 59 of 752 participants in the placebo group (7.8%) (relative risk reduction [1 minus the relative risk], 81.4%; P104 copies per milliliter) was shorter (0.4 weeks and 1.3 weeks, respectively). No dose-limiting toxic effects of REGEN-COV were noted. CONCLUSIONS Subcutaneous REGEN-COV prevented symptomatic Covid-19 and asymptomatic SARS-CoV-2 infection in previously uninfected household contacts of infected persons. Among the participants who became infected, REGEN-COV reduced the duration of symptomatic disease and the duration of a high viral load