Open Access Original Research Article

Sugar Transport in a Merging Phloem Vessels: A Hydrodynamic Model

W. I. A. Okuyade, T. M. Abbey, M. E. Abbey

Advances in Research, Volume 22, Issue 2, Page 1-11
DOI: 10.9734/air/2021/v22i230293

Green plants are the major tappers of the energy from the sun. The collected solar energy in the form of light is used to activate the chemical reaction occurring in matured leaves between carbon dioxide and water, leading to the synthesis of sugar (chemical energy). Two main transport processes are involved in the transport of mineral salt water from the soil through the roots, via the trunk and branches to the leaves where photosynthetic activity occurs, and the translocation of sugar from the leaves to where they are needed and possibly, stored. The xylem vessels bear the absorbed mineral salt water while the phloem vessels bear the manufactured sugar. In this study, neglecting the effects of occlusion and clogging of the phloem channels, we investigate the transport of sugars in the merging phloem vessels using the hydrodynamic approach. The model is designed using the Boussinesq approximation and solved semi-analytically using the regular perturbation series expansion solutions and Mathematica 11.2 computational software. Expressions for the concentration, temperature, and velocity are obtained and presented quantitatively and graphically. The results show among others, that increase in the merging angle causes a reduction in the concentration, temperature, and velocity profiles. However, there exists fluctuations in the concentration and temperature structures.

Open Access Original Research Article

Design and Optimise a GARField MRI Resonator

A. Muhammad, M. D. Oladipupo, I. K. Suleiman, O. L. Jane

Advances in Research, Volume 22, Issue 2, Page 12-27
DOI: 10.9734/air/2021/v22i230294

The design of a Nuclear Magnetic Resonance (NMR) sensor coil for a GARField NMR system was examined. The target design has a diameter about  mm and length  mm tuned to frequency of  MHz at 50 Ω total impedance. Nine different sets of coils were built with different numbers of turns (3, 5, and 7) and different thickness of wire to vary the wire resistance. The report was to examine based on the design parameters the best resonant circuit for a GARField MRI system. The acquired tuning characteristics from these resonant circuits were interpreted using MATLAB scripts and Excel spreadsheet to compare each coil with already existing theory of resonators. This was achieved by matching each resonant circuit using a match and tuning capacitor to the required frequency (22-23.4 MHz) and to 50 Ω total impedance at resonance. It was found that there is no easy method to estimate the inductance of the coil of wire. The result for the experimental inductance was found to be 0.5 µF and resistance of 0.4 Ω for a medium coil of wire with 5 numbers of turns, diameter of 0.45 and length of 0.7 mm. The initial attempt to fit the experimental data to that of the theory failed due to the absence of stray capacitance in the theory. However, when stray capacitor with value ranging between  pF was incorporated in parallel with the tank circuit, it was found that both the experiment and theory fit as expected.

Three coils were tested in the NMR laboratory using a GARField spectrometer to examine the best coil that will be suitable for NMR experiment. Coils were compared on the basis of signal to noise ratio (SNR) and P90 pulse length. It was found that medium coil of wire with 3 number of turns has the biggest SNR of 177 which is good for NMR procedures. On the other hand, coil with 5 numbers of turns has the shortest P90 pulse length of 2.0 µs which is good for spatial resolution. At all rate, this research have shown how theories are verified through experiment.

Open Access Original Research Article

Causes of Stress and Coping Strategies among Final Year Students in Tertiary Institutions in Nigeria

L. I. Akunne, G. C. Nnadi

Advances in Research, Volume 22, Issue 2, Page 28-35
DOI: 10.9734/air/2021/v22i230295

Aims: The study determined, the causes of stress among final year students in tertiary institutions in Nigeria. The study further determined coping strategies used in managing stress among final year students in tertiary institutions in Nigeria.

Study Design:  Descriptive survey research design

Place and Duration of Study: Final year students in tertiary institutions in Nigeria, between 2019/2020. 

Methodology:Stratified disproportionate random sampling was used to select 360 final year student’s 2019/2020. The instrument for data collection was a structured questionnaire titled causes of stress and coping strategies questionnaire. Cronbach alpha formula which yielded correlation coefficient of 0.70. Out of 360 copies of the questionnaire administered, 351 were correctly filled and returned giving a percentage return rate of 0.98. Data collected was analyzed using mean and standard deviation. The criterion mean was set at 2.50 and above as agree and below 2.49 as disagree.

Results: results presented in Table 1 reports that out of 11 causes of stress listed, respondents rated all the items agreed with mean score ranging from 2.74 to 3.77. Similarly, the grand mean score of 3.16 indicates that final year students in tertiary institutions in Nigeria agreed that the items listed are causes of stress among students. The standard deviation is heterogenous, this implies that the respondents’ scores are widely apart from the mean rating scores. The study further revealed that that out of 11 items listed on coping strategies used in managing stress, the respondents agreed that items 12, 15, 16, 17. 20 and 21 are coping strategies for managing stress while they disagreed on five items as coping strategies used in managing stress. The grand mean score of 2.56 indicates that final year students in tertiary institutions in Nigeria agreed that majority of the items listed are coping strategies used in managing stress. From the standard deviations scores recorded, there is homogeneity in respondents’ ratings.

Conclusion: In conclusion, stress exist and is caused by so many factors such as academic pressure, social problem, family stress, financial burden, management skills, uncomfortable classroom, adjustment to new environment among others. It is also concluded that students adopt and employ various coping strategies in managing stress. These strategies range from going for sporting activities when stressed, listening to music, and hanging out with friends and relatives for extra social activities.

Open Access Original Research Article

Bioavailability Studies of Vitamin A and E in Indigenous Vegetables and their Potential Use in the Management of HIV and AIDS

Rachel Nambafu, Sauda Swaleh, Hudson Nyambaka

Advances in Research, Volume 22, Issue 2, Page 36-44
DOI: 10.9734/air/2021/v22i230296

Levels of vitamins in selected indigenous vegetables in Butula, western Kenya were determined and foods containing high levels of vitamin A and E were used to make food formulation. The bioavailability of these vitamins in food formulation was estimated using algorithm procedure.

Determination of β-carotene and α-tocopherol content was done using HPLC procedure. Fresh blanched vegetables contained high levels of β-carotene; 4000 − 9700 µg/100g and α-tocopherol levels; 3000 − 7350 µg/100g. Solar dried vegetables contained β-carotene levels ranging from 572 − 854 µg/g and α-tocopherol levels ranging from 281 to 673 µg/g dry weights. Solar dried vegetables contained significantly lower (P<0.05) amounts of β-carotene and α-tocopherol as compared with fresh vegetables. The mean serum retinol α-tocopherol and β-carotene levels were 0.937, 0.144 and 17.787µmol/l respectively. Bioavailability estimated using algorithm indicated a +2.17 change in serum β-carotene and +7.776 changes in serum α-tocopherol, a positive indication that consumption of indigenous vegetables can meet the recommended dietary allowances of vitamins A (750 µg retinol equivalent/day) and E (8 mg/day). The bioavailable vitamins are capable of boosting the immune system and therefore delay early use of ARV’S.

Open Access Original Research Article

Effects of Project and Demonstration Teaching Methods on Male and Female Students’ Achievement and Retention in Basic Electricity in Technical Colleges

Chibueze Nweke Nwalo, Titus Iloduba Eze

Advances in Research, Volume 22, Issue 2, Page 50-62
DOI: 10.9734/air/2021/v22i230298

The study ascertained the effects of project and demonstration teaching methods on male and female students’ achievement and retention in basic electricity in technical colleges. Quasi-experimental design; precisely, pre-test, post-test and delayed post-test for non-randomized and unequal groups were used. Four research questions guided the study and four hypotheses were tested at 0.05 level of significance. Four technical colleges in Ebonyi State, each technical college offering basic electricity, were used. The population of the study comprised of 141 Technical College year II (TC II) students (85 males & 58 females). The project method instructional strategy group had 62 male and 13 female students whereas; the demonstration method instructional strategy group had 20 male and 46 female students. The instruments used in the study were Demonstration Method Instructional Manual (DMIM), Basic Electricity Achievement Test (BEAT) and Project Method Instructional Manual (PMIM), which were validated by three experts. The instrument (BEAT) was administered twice to twenty (20) TC11 students in Enugu State and Pearson’s Product Moment Correlation was used to obtain a reliability index of 0.89. Data collected for the study were analyzed using mean with standard deviation for research questions, while hypotheses were tested using Analysis of Covariance (ANCOVA). The study found that both the project and demonstration teaching methods improved male and female students’ performances in basic electricity. However, male and female students taught basic electricity using project teaching method had better academic performance and retention in basic electricity, indicating that project teaching method was more effective on male and female students’ achievement and retention in basic electricity than demonstration teaching method. The researchers therefore recommended project teaching method as a teaching strategy that could reduce the gender disparity in male and female students' achievement and retention.

Open Access Review Article

Healthcare System of Pakistan: Strengths and Weaknesses

Akhtar Ali, Farah Ahmad, Syed Hasan Danish, Nisha Zahid, Noor Israr, Sidra Farooq

Advances in Research, Volume 22, Issue 2, Page 45-49
DOI: 10.9734/air/2021/v22i230297

Each country of the world has its own health care system to follow, Pakistan has followed the healthcare system designed by British rulers since 1947. Primary healthcare, Secondary Healthcare and tertiary healthcare are the major parts of the defined healthcare system that are been practiced across the country. Pakistan has always participated and encouraged health promotion and delivery participating in Millennium Development Goal (MDG) program, encouraging public private partnership, investing in improvement of human resources and skills, introducing Basic Health Units (BHUs) and Rural Health centers. Though investment and inputs are set at achieving health for all but many weaknesses have slowed down the process of development. Poor governance and monitory policy, political influence and budget allocation issues have made it difficult to provide health on equal basis. The current review is aimed to discuss the strengths and weaknesses of healthcare system of Pakistan.