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Comparative Growth Response of Three Jatropha Species on Heavy Metal Contaminated Soil
Get PDFThis study investigated the comparative phytotoxcity effect of heavy metal contamination on Jatropha curcas, Jatropha gossypifolia and Jatropha multifida in contaminated soil from a dump site in Ibadan Nigeria. Seeds of J. curcas, J. gossypifolia and J. multifida were planted in a germination tray and later transplanted into polythene pots filled with 2kg of either control soil or heavy metal contaminated soil, a 3 × 2 factorial experiment laid out in complete randomized design (CRD) replicated four times was adopted; treatments imposed include T1 – J. curcas/Control Soil, T2 – J. gossypifolia/Control Soil, T3 – J. multifida/Control Soil, T4 – J. curcas/Contaminated soil, T5 – J. gossypifolia/Contaminated Soil, and T6 – J. multifida/Contaminated Soil. Weekly variation in growth parameters: the plant height, leave production and stem diameter were measured over the course of 12 weeks. The growth parameters were dependent on a combination of both specie type and level of heavy metal contamination of soil. J. multifida (T3) (36.93cm) performed best, comparable with J. gossypifolia (T2) (34.1cm) after 12 weeks while J. multifida (T6) had the lowest mean plant height (7.23cm) which is not significantly (p<0.05) different from other species on the contaminated soil; for leave production, J. gossypifolia (T2) produced the highest mean number of leaves (9.67) which is comparable with J. multifida (T3) (9.00) and less so with J. curcas (T1) (6.67) with significant leave losses on the contaminated soils after 12 weeks; variation in stem diameter shows that J. curcas (T1) had the highest stem girth (1.96 mm) which is comparable to the value obtained for J. curcas (T4) (1.95mm), while J. multifida (T6) had the lowest stem girth (1.09 mm). J. gossypifolia (T2) and J. multifida (T3) had comparable stem girth of 1.57mm and 1.47mm respectively. Toxicity of heavy metals in the contaminated soil greatly affect the growth parameters of the Jatropha
Cryptosporidium in the Philippines
Get PDFThis short review provides an overview regarding the research findings on the occurrence of Cryptosporidium in the Philippines. It seeks to set conjecture about its possible role on the increasing waterborne disease incidences in the country. Intensive search of journal articles was done among major databases, online. The first report of Cryptosporidium infection in the country was in 1985. Past more than 30 years, Cryptosporidium is not yet well-understood in the Philippines, but an increasing research interest has been observed among Filipinos in the past few years. Recently, waterborne transmission of the infection appeared in the studies to be more potent than zoonotic and person-to-person transmissions. An improvement on the detection methods was also observed, giving an improved knowledge on the molecular diversity of Cryptosporidium in the country. Despite these improvements, the paucity of the data regarding the impact of Cryptosporidium to the public health in the Philippines is still apparent. One Health approach is recommended to fully understand the interconnections between human, animal, and environment as reservoirs of the infective stage of the parasite. Dedication of the researchers in understanding their geographical distribution, molecular diversity, and environmental and climatic behaviour will eventually uncover the public health implications of Cryptosporidium in the country
Parameter Estimation of Spring-Damping System using Unconstrained Optimization by the Quasi-Newton Methods using Line Search Techniques
Get PDFOptimization is the basic tools to study the behaviour of many complicated mechanical systems by having the knowledge of differential equations which determine the system. The basis of this paper was to present a method to estimate the parameters such as spring constant and damping coefficient of the spring damped system by unconstrained optimization using derivative methods Such as quasi-newton method by Broyden-Fletcher-Goldfarb-Shanno and davidon-Fletcher-Powell hessian updating method by using backtracking line search methods along with Armijo’s condition.it uses the output error approximation procedure. It shows the convergence of different methods which are used to estimate the parameters and how accurately they are measured
Integration of Audio-Visual and Traditional Practices for Effective Classroom Teaching
Get PDFEducation is one of the principal buildings blocks of the civilization. Since many centuries, teaching has been extensively accepted as a Nobel profession. The expected duty of teachers is to deliver their best in receiving and conveying the information correctly to their students in class and they do. But, in the modern era, when the young generation is conquered by the technological advancements, implementation of innovative teaching practices may help to improve the education system and can enhance the learning potential. The present article focuses on the integration of traditional and audio-video teaching practices
Study of the Effect of Crude Oils on the Metallic Corrosion
Get PDFCorrosion is a severe matter regarding the most of metal using industries such as the crude oil refining. The formation of the oxides, sulfides or hydroxides on the surface of metal due to the chemical reaction between metals and surrounding is the corrosion that highly depended on the corrosive properties of crude oil as well as the chemical composition of ferrous metals since it was expected to investigate the effect of Murban and Das blend crude oils on the rate of corrosion of seven different ferrous metals which are used in the crude oil refining industry and investigate the change in hardness of metals. The sulfur content, acidity and salt content of each crude oil were determined. A series of similar pieces of seven different types of ferrous metals were immersed in each crude oil separately and their rates of corrosion were determined by using their relative weight loss after 15, 30 and 45 days. The corroded metal surfaces were observed under the microscope. The hardness of each metal piece was tested before the immersion in crude oil and after the corrosion with the aid of Vicker’s hardness tester. The metallic concentrations of each crude oil sample were tested using atomic absorption spectroscopy (AAS). The Das blend crude oil contained higher sulfur content and acidity than Murban crude oil. Carbon steel metal pieces showed the highest corrosion rates whereas the stainless-steel metal pieces showed the least corrosion rates in both crude oils since that found significant Fe and Cu concentrations from some of crude oil samples. The mild steel and the Monel showed relatively intermediate corrosion rates compared to the other types of ferrous metal pieces in both crude oils. There was a slight decrease in the initial hardness of all the ferrous metal pieces due to corrosion
Coldspots and Hotspots of Agriculture in Nigeria; Any Hope for Youth and Women?
Get PDFAfrica has 25 percent of the world’s arable land, yet it cannot boast of food sufficiency let alone tapping into food export opportunities. It is no longer news that the women folks in Africa are greatly marginalised and confronted by numerous challenges. Meanwhile, youth engagement in agriculture is presently seen as one of the ways to achieve zero hunger by 2030 as set by the sustainable development goals. Using critical review approach, this study aims to review past and present agriculture programs aimed at encouraging youth and women in agriculture. We found that access to land and weak land tenure system; high cost and unavailability of inputs, infrastructural deficit; poor access to information; inadequate extension service and poor pricing policy are the main constraints for the youth and women in Nigeria. However, opportunities such as employment, large market, vast arable land, increasing investment of government and private sector and value addition. The policy message from this study is straight: effort should be intensified and constructive approaches through polices that support pathways in which opportunities can be harnessed and constraints offed
The Impact of Biofuels on Food Prices; The Experiences of Brazil and United States
Get PDFUsing crops for fuel generates concerns over competition with food uses. In 2008 a global food crisis hit the world during a record-high commodity and energy prices that prompted hunger and political unrest in developing countries. This took place at the same time when biofuel production, reached its pinnacle in developed countries. This paper examines the effect that biofuel prices and or production has had on food prices in Brazil and United States (U.S.) by employing the panel cointegration and Dynamic Ordinary Least Squares (DOLS) method of analysis. In regressing food prices as a function of demand and supply factors, such as oil prices, biofuel prices, interest rates and biofuel production, the study found that the increase in biofuels production over the past eighteen years has had a significant impact on food prices. Over the period January 1995- December 2013, the study estimates that a one hundred percent increase in biofuels production across time and between countries results in the increase of food prices by 21,9%. The study therefore rejects the null hypothesis that states, biofuel production does not have a statistically significant negative impact on food prices in U.S. and Brazil, and accepts the alternative that biofuel production does have a statistically significant negative impact on food prices in U.S. and Brazil. Other predictors of food prices that the study revealed as significant were oil and interest rates. Policy recommendations for other countries like South Africa are therefore, made based on the results obtained
Impacts of Certain Imposed Factors on Education and Educationists in Punjab, India
Get PDFQuality achievements, teacher inputs and outputs require a universal level if our country have to compete with the developed nations. Firstly, this paper examines problems while implementing those according to the present conditions in the schools of Punjab and secondly how those problems affect educationists as employs and educationists as common man. Teacher can fulfil the desires of society if he himself is mentally free from hardships in social responsibilities and free from the threat of insecure future. Education is only way to achieve desired goals in life and to make people aware of their prospect and potentials. Due to disparities presented in the rural and urban conditions of schools of Punjab there are some issues presented which affects the education system but are ignored ever. Often ignored factors, policies and structures either by political will or by bureaucracy have many adverse effects on the thousands of educationists and their families throughout life. This paper thus depicts categories of Para teacher schemes including contractual and departmental, Unequal wages but equal desired output by department, same policies for rural and urban staff ignoring regional disparities, prioritization of subjects since Kothari commission(1964-1966) without considering demand of today’s 21st century globalised world, poor level of teacher trainings , misinterpretations of compulsory education, Annual confidential reports (ACR’s) without feedback to employs, non-teaching works due to lack of support staff in schools which suffers teacher student contact timings and finally partial transfer policies in which some remained in urban areas forever and others remained in faraway places forever until and unless blessed by political will and ignoring goals of justice, liberty and equality and in last some remedies also suggested for the revision consideration. School education forms the foundation of an education system and this can be achieved only by providing the free environment
Contribution of Drude and Brendel Model Terms to the Dielectric Function; A case of TiO2:Nb Thin Films
Get PDFoai:ojs2.journals.aijr.org:article/299Parametric modeling provides a mean of deeper understanding to the properties of materials. Dielectric function is one of the key parameters which can provide information on the dielectric nature of a thin film or bulk materials. It can be obtained by modeling the material using appropriate existing, new or modified models. In our work, we utilized existing Brendel and Drude models to extract the optical constants from spectrophotometric data of fabricated undoped and niobium doped titanium oxide thin films. The individual contributions by the two models were studied to establish influence on the dielectric function. The effect of dopants on their influences was also analyzed. Results indicate a minimal contribution from the Drude term due to the dielectric nature of the undoped films. However as doping levels increase, the rise in the concentration of free electrons favors the use of Drude model
Performance and Prospects of Severe Plastic Deformation for Effective Biomedical Titanium Alloys
Get PDFApplication of severe plastic deformation (SPD) technology to process effective biomedical titanium alloys has shown promising results at laboratory scale. However, more research is still required before adopting this technology from laboratory scale to industrial scale production. This review presents performance and prospects of SPD for effective ultra-fine/nanograin structure-biomedical titanium alloys. Effective biomedical titanium alloys should have desired properties for the medical application. The properties include; high static and fatigue strengths, surface hardness for wear resistance, good ductility, corrosion resistance and biocompatibility. Based on current works reported in the literature, the review focused on; high-pressure torsion (HPT), equal channel angular pressing (ECAP), asymmetric rolling (AR), accumulative roll bonding (ARB) and repetitive corrugation and straightening (RCS). Overview of biomedical application of titanium alloys and desired material properties is presented. A detail discussion on the working principle, performance (e.g. induced strength, hardness, grain size and texture etc.) and material deformation homogeneity of each SPD method are presented. Also, prospects and challenges of each SPD method to be implemented at industrial scale for continuous and mass production are highlighted. The review concludes with the effectiveness of SPD processes, characteristics of processed samples and suggestion of future work for SPD to process effective biomedical titanium alloys at industrial scale