European Journal of Applied Sciences

Antibacterial Activity of Verticillin D Produced by Endophyte Clonostachys Rosea EC 28

Sagou Dominique , Pakora Gilles Alex, Dodehe Yeo, N'Guessan Jean David — Sat, 10 Sep 2022 00:00:00 +0000

The objective of this work was to determine the antibacterial effect of endophytic fungi of Ceiba pentandra and to identify the compound(s) responsible for this activity. The antibacterial screening of the mycelium of endophytic fungi isolated from the bark of C. pentadra was evaluated against multiresistant strains E. coli and S. aureus. This screening led to the selection of isolate EC 28 for its ability to effectively inhibit the growth of the bacterial strains tested. Analysis of morphological characters and ITS rDNA sequences identified EC 28 as Clonostachys rosea. EC 28 was cultivated and extract. From the crude extract, two compounds, ergosterol and verticillin D, were isolated and identified. The in vitro activity of each compound against the growth of five strains bacterial multiresistant were assessed. Ergosterol did not have any activity. Verticillin D was active on all strains of bacterial multiresistant E. coli 942, E. coli 4814, S. aureus 931, S. aureus 934, and K. pneumonia 815 with respective MICs of 18.75; 18.75; 18.75; 3 and 37.5 µg/ ml.

Calorific Value of Rubberwood Biomass Along the Tree

Gladys Ama Quartey, John Frank Eshun, Eric Donkor Marfo — Sat, 10 Sep 2022 00:00:00 +0000

Rubberwood is one of the major plantation crops grown mainly in the Western Region of Ghana. They are mostly utilised for their latex. Rubber trees that are aged and low yielding can be cut down and properly utilised as fuelwood. In Ghana, there is a high demand for fuelwood in most domestic homes and rubberwood is one of the tree species with potential use as fuelwood. Even though gas has been promoted as an energy source for heating and cooking activities in Ghana, it remains expensive, and its affordability, therefore, remains out of reach of many people. Rubberwood, which is plantation grown can, therefore, be considered as fuelwood. In this study, the calorific values of rubberwood biomass from a plantation were determined using samples from the bottom, middle, branch, and top parts of the stem. The calorific values of rubber wood biomass from different sections of the tree were determined in accordance with standard laboratory methods using a bomb calorimeter. The calorific values obtained were 17.194 MJ/kg for the branch, 17.225 MJ/kg for the top, 17.595 MJ/kg for the middle, and 17.702 MJ/kg for the bottom. The trend of the values shows that the calorific value decreases from the bottom through the top of the stem to the branch. The calorific value of rubberwood was comparable to other high-performing tree species used for fuelwoods and therefore has the potential to be used for fuelwood.

Nutritional Status and Early Food Diversification in Infants Aged 200 Days in Three Municipalities of Abidjan

Sat, 17 Sep 2022 00:00:00 +0000

It appears from this study that certain socio-demographic parameters influence the nutritional status of infants. The early introduction of foods greatly affects the nutritional status of children. For each manifestation of malnutrition, the prevalence is high among infants living in low socioeconomic households to infants in well-to-do households. This study shows that the majority of mothers are aged from 20 to 29 and 34% are pupils or students. Among them, 50% live in households with a high standard of living. Despite advice and recommendations on the practice of exclusive breastfeeding, 60% of infants started early food diversification between 0-119 days. The Height-for-Age (H/A) study indicates that among infants 21.6% have at-risk nutritional status, while 6.4% are stunted. The present study also indicates at the Weight/Height (W/T) level that among infants 26.9% have a nutritional status at risk and 3.3% are wasted. Regarding the weight-for-age (W/A) parameter, it appears that the proportion of children with a nutritional status at risk is 33.3% and 10.7% underweight. All infants who received early complementary foods are at risk of malnutrition.

Use of Rice Husk Ash for Copper, Chromium, Zinc, and Lead Bioremediation in Crude Oil-Contaminated Soil

Reward Kokah Douglas, Ayebatin Fou, Peremelade Perez Araka — Sat, 17 Sep 2022 00:00:00 +0000

In this study, 1kg soil sample was artificially contaminated with 250ml crude oil and incubated for 4-day; and heavy metals-copper (Cu), chromium (Cr), zinc (Zn), and lead (Pb) concentrations were measured by flame atomic adsorption spectrometry (AAS) to be 11.68mg/kg, 38.96mg/kg, 59.34mg/kg, and 28.56mg/kg, respectively. Fresh rice hush ash (RHA = 0.5kg) was prepared from rice husk (RH) and used for the bioremediation of these metals in a 2-month experiment. The RHA reduced the Cu, Cr, Zn, and Pb concentrations by 33%, 29%, 27%, and 25%, respectively. Considering the quantity of RHA to the contaminated soil mass ratio (0.5:1.0), and the short period of the experiment (i.e., 2-month), RHA amendment is promising for the bioremediation of heavy metals polluted soils. This study provides the first reference point on the effectiveness of RHA for the remediation of heavy metals in polluted soils in the Niger Delta,Nigeria. Thus, we recommend field-trials and longer-term study to better assess the long-term applicability of this option for bioremediation of polluted soils.

Equilibrium and Kinetic Studies for the Removal of Zn (Ii) and Cr (Vi) Ions from Aqueous Solution Using Pineapple Peels as an Adsorbent

Sat, 17 Sep 2022 00:00:00 +0000

Adsorption is one of the methods extensively reported to have been successfully used for the removal of potentially toxic metals (PTMs) from wastewater. In this study, the equilibrium and kinetics studies of the application of pineapple peels as an adsorbent for the removal of Zn(II) and Cr(VI) ions from aqueous solutions was investigated in a batch process. The initial and equilibrium metal ion concentrations of the solutions were determined by Atomic Absorption Spectroscopy. The characterization of the adsorbent was done using the Scanning Electron Microscope and Fourier Transform Infrared Spectroscopy (FTIR). The FTIRspectra confirmed that there are different functional groups in adsorbents, which are able to react with metal ions in aqueous solution. Effects of initial pH, initial metal ions concentrations, shakingtime and solid/liquid ratio on metal ions biosorption were also investigated. Adsorption of metal ions were pH dependent and the results indicate that the optimum pH for the removal of Zn (II) and Cr (IV) was found to be 6.0and the maximum percentage removal of Zn (II) and Cr (IV)at this pH were 86.45% and 92.56% respectively along the whole range of initial concentrations.Three adsorption isotherm models, Langmuir, Freundlich and Temkin were used to simulate the equilibrium data. The experimental data were best fitted to the Langmuir isotherm when compared with other models with the highest R² values of 0.937 and 0.987 for Zn(II) and Cr(VI) ions respectively. The achieved results confirmed that the adsorption of zinc and chromium were in good compliance with pseudo-first-order reaction kinetic suggesting that the adsorption is apparently physisorption and the thermodynamics analysis of the result showed that the process is spontaneous and exothermic.The pineapple peels investigated in this study showed good potential for the removal of zinc and chromium from aqueous solutions

A Proposal and Simulation with NS3 of a New offloading Algorithm between LTE/LTE-Advanced and Wi-Fi

Luc Ange Harry LYEB, Eric Michel DEUSSOM DJOMADJI, Emmanuel TONYE — Sat, 17 Sep 2022 00:00:00 +0000

The field of mobile telecommunications is an integral part of our society. In the wake of IT, it is implemented and used in all areas of society. This deep anchoring, which mobile networks use today, poses significant problems for operators in terms of speed, capacity demands and customer satisfaction, particularly for the quality of services, but also in terms of profitability and cost of services investments. Reports from Ericsson and Cisco which are representative bases for calculating world total data traffic in cellular mobile networks predict that the number of devices connected to IP networks will be more than three times the global population by 2023. There will be 3.6 networked devices per capita by 2023, up from 2.4 networked devices per capita in 2018. There will be 29.3 billion networked devices by 2023, up from 18.4 billion in 2018. To answer these challenges, two choices are offered to the operators the evolution of the standards or the interconnection of several networks. In this order of idea, we carried out an 4G/4G+ -Wi-Fi offloading simulation algorithm. It was up to us to design an offloading algorithm and then to simulate through a dedicated environment in a scenario allowing to implement it. To achieve this, it was first necessary for us to understand the concept of mobile data offload, to know the types of mobile data offload and to choose one on which the present work will be based. Later we carried out an analysis of the existing data offload algorithms to be able to bring out the limits. From these limits we have designed and proposed a new traffic offloading algorithm with a different approach compared to the existing one studied in the literature. After all this, we have developed and simulated a scenario comprising a 3GPP network in this case the 4G + network, a non 3GPP network in this case the WiFi network, and we have implemented our algorithm via NS3 network simulation software. With this work, we have proposed a solution to overcome an investment deemed expensive to deploy 5G in Africa.

Artificial Intelligence (A.I) Application in Foreign Language Teaching and Learning

Pham Thanh Nga — Sat, 17 Sep 2022 00:00:00 +0000

In this article, the author will analyze specifically the problem of using artificial intelligence (AI) technology in teaching Foreign Language at the higher education. From there, the author will propose some solutions to further improve the effectiveness of using AI technology in teaching and learning English in particular and foreign languages in general in Vietnam in the next period.

Comparative Study on Frying Performance of Three Different Oils for the Preparation of Ripe Plantain Banana

Sat, 17 Sep 2022 00:00:00 +0000

In this study, the effect of traditional frying on oils degradation namely frial oil (FO), soybean oil (SBO) and refined blanded deodorized palm olein oil (RBDPOo) was investigated. Oils degradation was monitored by measuring the free fatty acids (FFA), peroxides (PV), p-anisidine (p-AV),) iodine value (IV), totox value (TxV), total polar compounds (TPC), fatty acid composition and C18:2/C16:0 ratio, viscosity, conjugated dienes (CD) value and oil color. Oils samples were taken every 4 h of frying during 10 consecutive days. Values of all physic-chemicals measures significantly changed with frying and type of fat. Values of FFA, p-AV, TPC, CD, TxV, ΔE and viscosity increased significantly, whereas IV and C18:2/C16:0 ratio decreased significantly at the end of the frying processes. Excepted PV, where the values reached a maximum and then decreased at to final frying. These results suggested that a traditional frying process has an impact on degradation on edible oils.

Shear Modulus and Yield Stress Change with Pressure and Temperature

Yehuda Partom — Sat, 17 Sep 2022 00:00:00 +0000

It is well known that the shear modulus (G) and the yield stress (Y) of metals increase with pressure (P) and decrease with temperature (T). Steinberg [1], in his popular compendium of dynamic material properties, assumes for Y/Y₀(P,T)=G/G₀(P,T) linear relations based on tests at ambient conditions. But recent tests of high-pressure dynamic loading of certain metals yielded results that generally deviate from Steinberg’s equations. Here we use a different approach to estimate G/G₀(P,T). As a first approximation we let G/G₀ follow from the assumption of constant Poisson ratio (n). This leads to G/G₀=K/K₀, where K is the isentropic bulk modulus. With this assumption we compute the longitudinal sound speed of tantalum along its principal Hugoniot curve, and compare the result to recent measurements. There is a slight disagreement which we correct by assuming (second approximation) that Poisson’s ratio decreases slightly with pressure, and increases slightly with temperature. As K is always available in a hydrocode run from the equation of state, so are therefore also G/G₀ and Y/Y₀.

A Review of Green Public Procurement in the EU

Dimitris Karnabos, Roido Mitoula, Alexandra Tragaki, Constantinos Apostolopoulos — Thu, 22 Sep 2022 00:00:00 +0000

Public authorities are major consumers in Europe. Each year they spend approximately 2 trillion euros, equivalent to some 19% of the EU’s Gross Domestic Product on the purchase of goods, such as office equipment, building components and transport vehicles; services, such as buildings maintenance, transport services, cleaning and catering services and works. By promoting and using "Green Public Procurement (GPP)" public authorities can drive the market to greener products and services, achieving an important reduction of the environmental impacts. Within the EU public procurement is subject to a number of sources of Community law. In addition, there are common criteria for the adoption of Green Public Procurement in specific sectors (i.e. copying and graphic paper, office IT equipment, cleaning products and services, transport, construction, etc.) and a number of sources of interpretation of the relevant laws and principles (i.e. the "Buying Green handbook"). On the review of GPP the work team firstly analyzed the EU strategic policy, and then chose a series of examples to evaluate the implementation of GPP, illustrate how public authorities have made greener purchasing a reality and provide guidance to others. The evaluation included some of the most interesting case studies related to different countries (i.e. Netherlands, Denmark, Sweden, Malta, Austria, Belgium, Spain, Switzerland, Slovenia, Bulgaria, Latvia, France, UK, Germany, Greece, Finland, etc.) and collected by European Commission over the years. According to the results of the evaluation the benefits associated with GPP are not limited only to environmental impact, but can include everything from social and health to economic and political benefits. Today even if the concept of GPP has been widely recognised as a useful tool, it remains a voluntary instrument. Member States should be encouraged to draw up Action Plans for greening their public procurement. Among other, the coming years should be a growing political commitment at national, EU and international level.

Identification of Geometrical Parameters of an Operational Railway Route Determined by the Curvature of the Track Axis

Wladyslaw KOC — Thu, 22 Sep 2022 00:00:00 +0000

The paper presents a detailed procedure for determining the curvature of the track axis with the use of the moving chord method, with a view to practical application of this method to identify the geometric parameters of the operational railway track. The method of determining the coordinates of the end of the virtual chord brought forward and backward, and then determining the curvature occurring at a given measurement point, has been explained. The presented course of action is based on the use of the given calculation formulas and is of a sequential nature; there is no need to use numerical methods. As part of the curvature calculation procedure, it is also possible to determine the values of the directional angle of the route. The verification of the application possibilities of the moving chord method was carried out in the presented calculation example, on the basis of the determined Cartesian coordinates of the axis of the railway track in use. The obtained curvature plots, which clearly differ from the plots for model layouts as they have a less regular, oscillating character, which results from the track deformation and measurement error. However, this did not prevent them from making it possible to estimate the basic geometrical parameters of the measured layout. The implementation of the presented procedure should significantly improve the process of identifying the geometric layouts of the track in the horizontal plane.

A Logistic Curve in the SIR Model and Its Application to Deaths by COVID-19 in Japan

Takesi Saito, Kazuyasu Shigemoto — Sat, 24 Sep 2022 00:00:00 +0000

Approximate solutions of SIR equations are given, based on a logistic growth curve in the Biology. These solutions are applied to fix the basic reproduction number α and the removed ratio c, especially from data of accumulated number of deaths in Japan COVID-19. We then discuss the end of the epidemic. These logistic curve results are compared with the exact results of the SIR model.