AN EVENT ORIENTED APPROACH TO DIGITAL FORENSICS FOR TRACKING CRIMINALS

In this paper, we present a framework for digital forensics that includes an investigation process model  based on physical crime scene procedures. In this model, each digital device is considered a digital crime scene, which is included in the physical crime scene where it is located. The investigation includes the preservation of the system, the search for digital evidence, and the reconstruction of digital events. The focus of the investigation is on the reconstruction of events using evidence so that hypotheses can be developed and tested. This paper also includes definitions and descriptions of the basic and core concepts that the framework uses

Prevalence of hepatitis B, hepatitis C and human immunodeficiency viruses, and evaluation of risk factors for transmission: Report of a population screening in Nigeria

Background. Hepatitis B virus (HBV), hepatitis C virus (HCV) and HIV are common blood-borne infections unevenly distributed across regions in Nigeria. Few population-based prevalence studies have been done in Nigeria.Objective. To determine the prevalence of HBV, HCV and HIV and risk factors for infection with these viruses in a Nigerian population.Methods. Hepatitis B surface antigen, anti-HCV and HIV were assayed in 1 498 healthy adult participants. A structured questionnaire was used to assess risk factors for viral acquisition. Bivariate analysis was used to compare differences in sociodemographic characteristics. Significant risk factors were identified by stepwise logistic regression. A p-value <0.05 was considered significant.Results. The prevalences of HBV, HCV and HIV were 8.8%, 10.0% and 12.9%, respectively, with urban/rural disparity. HBV/HCV positivity was higher among males than females. The reverse was true for HIV. Age was significantly associated with being HBV-, HCV- or HIV positive. Communal use of a toothbrush was significantly associated with HBV positivity in the final model (odds ratio 2.46, 95% confidence interval 1.45 - 4.18).Conclusions. The prevalence of HBV, HCV and HIV infection is high in Nigeria, with urban/rural disparity. HCV may be more of a public health concern than HBV in some communities. Population-based studies are required to provide vital data to inform optimal national control strategies

Process modeling and simulation of Gmelina arborea (GmW) and Mansonia altissima (MaW) wood drying

This study simulate the process modeling of drying characteristics of Gmelina arborea (GmW) and Mansonia altissima (MaW) wood under the influence of various process variables such as drying time, drying temperature, and airflow velocity. GmW and MaW moisture desorption isotherms, kinetics, and thermodynamics were also studied. Five (5) thin-layer and desorption isotherm drying models were used to model the moisture ratio and water activity data from the process. According to the anatomical analysis, the GmW sample has an average lumen size of 147.44 m, indicating a high moisture content. The results showed that the Guggenheim, Anderson, and de Boer (GAB) model with the lowest sum of squared error value (0.046) demonstrated the best-fit to the experimental desorption data for GmW samples and the Henderson-P model for MaW samples, while the Demir et al. model emerged as the best kinetics model fit for describing the moisture desorption isotherm and thin-layer drying kinetics. GmW effective diffusivity (Deff) values ranged from 3.671 × 10−8 to 5.378 × 10−8 m2/s and MaW effective diffusivity (Deff) values ranged from 2.923 × 10−8 to 4.678 × 10−8 m2/s. GmW and MaW activation energies were 252.702 kJ/mol and 313.604 kJ/mol, respectively. The thermodynamic studies revealed that the heat and mass transfer coefficients varied linearly with temperature, as the change in enthalpy (ΔH) and change in entropy (ΔS) decreased while the Gibbs free energy (ΔG) increased. The results obtained from this study demonstrated that the proposed drying process modeling and simulation approach could be successfully applied to investigate the wood drying phenomena. The information can be used to reduce the drying costs and improve the wood quality

Performance evaluation of mixed mode passive solar stock fish dryer

The performance evaluation of Mixed-Mode Passive Solar Dryer for drying codfish (Gadusmorhua) was conducted. The dryer is comprised of among other things, materials for sensible heat storage to discharge heat during the off-sunshine period. The drying chamber is integrated with a suction device to aid the convective airflow to avoid reversible reaction during the discharge of accumulated moisture. The solar dryer was evaluated with fresh codfish samples at the initial moisture content of 79% (wet basis). The samples were divided into sets. A set was treated with Moringa Oleifera and the second set with salt solution. The results showed that, for Moringa and salt treatments, the moisture content of the codfish was reduced to 16.03% and 13.33% (wet basis) respectively using the solar dryer while 19.55% and 13.46% respectively under ambient condition in six days. Laboratory tests showed that bacteria and fungi count for Moringa and salt treated codfish under solar dryer were below consumable limits

Determination of Optimum Process Parameters of the Drying Rate of Cassava Samples Using the Square Design Method

Drying is the removal of moisture content and other chemical compositions. The study aims to improve the process parameters involved in cassava chip drying. A statistical approach was utilized to evaluate the significance of the drying variables, such as the various cassava species, the drying temperature, and the drying duration, and their influences on the drying rate of cassava chips. The Latin Square Experiment Design was taken into account when determining the interaction between the critical optimum parameters. At the P 0.05 significance level, an ANOVA was used to analyze the linear and interaction influence of the drying variables on various quality parameters. The study used analysis to compare the F-statistic at four degrees of freedom and obtained an optimal significant level of 3.26. Also, the results showed a significant influence of temperature and period of drying on the drying rate of the cassava chips, but the cassava species did not affect the drying rate of the cassava chips. Also, the results from the statistical analysis were validated and can be employed for monitoring the drying process of cassava chips

Development of auto sanitizer for mitigation of Covid-19 – Using solar powered aluminum structural chamber

The use of auto sanitizer in the disinfection of human body and surfaces against dangerous micro-organisms like coronavirus diseases that are infectious is of great importance to schools, family, community, and public health. The outbreak of novel Coronavirus in late 2019, which has crippled the academic, social, and economic activities globally is as a result of unhygienic activities of living creatures like, man, and animals. But a good number of technologies can be developed to tackle the emergence of this novel infectious virus. The challenge of COVID-19 that resulted to ill-health, high death rate, and shutdown of activities was being addressed radically by different medical practitioners, engineers through various practical innovations, methods and mitigation approach - ranging from the use of face shields and respiratory facemasks to practicing of social and physical distancing. This part of preventive measures has led us to developing an Auto Sanitizer that is made of Aluminum Chamber which does not wet the cloth or human body but disinfects it against COVID-19

Knowledge of hepatitis B virus infection among traders

Introduction: Hepatitis B virus (HBV) is a public health problem in Nigeria, with 13% of its general population having evidence of a previous or current infection. Lack of awareness of HBV, its risk factors, and its consequences are recognized as major deterrents to adopting positive preventive behavior including immunization among HBV high-risk groups. Objective: The objective of this study is to evaluate the knowledge, attitude, and practice (KAP) of HBV infection among traders.Materials and Methods: A structured KAP questionnaire on HBV infection was administered to traders as part of the activities to mark the World Hepatitis Day in 2014. A score was created for the correct answer to 20 questions.Results: A total of 335 traders were interviewed for this study. The mean age was 33.08 ± 13.8 years and the median age was 29 years. There were 165 males and 170 females. Majority of the traders had secondary education (57.1%) and were of the Ibibio and Igbo tribes. Only 10.4% had HBV vaccination. Only 44.2% of the traders reported having any knowledge of HBV. The most common source for the knowledge was television/radio (25%) and hospitals (22%). The median (interquartile range) of the overall KAP score was low (11, 5–16). The score was least in persons aged 35 years and above, but the difference was not statistically significant (P = 0.33).Conclusion: The knowledge of HBV is low among traders in Calabar metropolis. There is need to intensify educational campaigns for the general public.Keywords: Attitude and practice, hepatitis B virus, knowledge, trader