Dominator Chromatic numbers of orientations of trees

ODAM-Vol. 4 (2021), Issue 1, pp. 4 – 11 Open Access Full-Text PDF
Michael Cary
Abstract: In this paper we prove that the dominator chromatic number of every oriented tree is invariant under reversal of orientation. In addition to this marquee result, we also prove the exact dominator chromatic number for arborescences and anti-arborescences as well as bounds on other orientations of oft studied tree topologies including generalized stars and caterpillars.
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Variation of radiofrequency intensities from the DTTV-transmitter in Kampala Metropolitan; Uganda

EASL-Vol. 4 (2021), Issue 1, pp. 21 – 29 Open Access Full-Text PDF
Peter Opio, Akisophel Kisolo, Willy Okullo, Tumps. W. Ireeta
Abstract: This paper presents the variation of radiofrequencies intensities from the DTTV-transmitter in Kampala Metropolitan for the sub 700 MHz (470-694 MHz) and the 700 MHz (694-790 MHz) frequency bands. The results of this study showed that though all the measurement locations from the transmitter have a good reception of DTTV signals, their radiofrequency intensities varied at the different points on the same measurement location at a constant distance from the DTTV transmitter. The study further showed that there is a general decrease in the radiofrequency intensities for the sub 700 MHz frequency band and a slight general increase in the radiofrequency intensities for the 700 MHz frequency band. This research revealed that the measured Reference Signal Received Power (RSRP) values for all the measurement locations where within the IEEE and FCC recommended values for any DTTV signal reception.
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A variety of uncertainty principles for the Hankel-Stockwell transform

OMA-Vol. 5 (2021), Issue 1, pp. 22 – 34 Open Access Full-Text PDF
Khaled Hleili
Abstract: In this work, we establish \(L^p\) local uncertainty principle for the Hankel-Stockwell transform and we deduce \(L^p\) version of Heisenberg-Pauli-Weyl uncertainty principle. Next, By combining these principles and the techniques of Donoho-Stark we present uncertainty principles of concentration type in the \(L^p\) theory, when \(1\)<\(p\leqslant2\). Finally, Pitt's inequality and Beckner's uncertainty principle are proved for this transform.
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Convergence analysis for a fast class of multi-step Chebyshev-Halley-type methods under weak conditions

OMS-Vol. 5 (2021), Issue 1, pp. 34 – 43 Open Access Full-Text PDF
Samundra Regmi, Ioannis K. Argyros, Santhosh George
Abstract: In this study a convergence analysis for a fast multi-step Chebyshe-Halley-type method for solving nonlinear equations involving Banach space valued operator is presented. We introduce a more precise convergence region containing the iterates leading to tighter Lipschitz constants and functions. This way advantages are obtained in both the local as well as the semi-local convergence case under the same computational cost such as: extended convergence domain, tighter error bounds on the distances involved and a more precise information on the location of the solution. The new technique can be used to extend the applicability of other iterative methods. The numerical examples further validate the theoretical results.
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Isolation and identification of Aspergilli causing Banana fruit rot

OJC-Vol. 4 (2021), Issue 1, pp. 8 – 18 Open Access Full-Text PDF
Fatima Ali, Naureen Akhtar, Shazia Shafique, Sobiya Shafique
Abstract: Banana is a commercially and nutritionally important food crop worldwide and is affected by several fungal diseases. The most important post-harvest disease is fruit rotting. Fruit rot is responsible for significant losses in banana. The present study was therefore, designed to isolate and explore the mycoflora associated with banana fruit rot. For this, infected samples were grown on different media to obtain pure cultures of isolated fungal pathogens. Identifications were made initially on morphological basis and then confirmed by genetic analysis. A comprehensive study of micro and macroscopic features revealed four Aspergillus species with two of Aspergillus fumigatus, one of Aspergillus flavus and one of Aspergillus niger. Genetic analysis by Nucleotide sequence analysis of ITS region of rDNA was performed. The sequence alignment of two different isolates of Aspergillus fumigatus showed 99% homology to different strains deposited in Genbank i.e., 004(KU321562.1), SK1(KM207771.1), and 98% homology to AHBR16(KF305755.1),  SF8(KX011021.1).
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Evaluation of the anthelmintic properties of a traditional remedy based on a mixture of red algae using an in vitro assay on gastrointestinal nematodes of donkeys

OJC-Vol. 4 (2021), Issue 1, pp. 1 – 7 Open Access Full-Text PDF
Michela Maestrini, Marcelo Beltrão Molento, Simone Mancini, Francesco Saverio Robustelli della Cuna, Giovanni Furnari, Donatella Serio, Laura Cornara, Stefania Perrucci
Abstract: The anthelmintic properties and composition of an Italian traditional anthelmintic remedy based on a red algae mixture (RAE) was assessed using the egg hatch test (EHT). The ability of different dilutions \((1.0, 5.0, 50,\) or \(100%)\) of RAE was determined and compared with the positive and negative controls against gastrointestinal nematode (GIN) of donkeys. The experiment was performed in triplicate. Data were analysed using the ANOVA and Tukey test. In the mixture, Palisada tenerrima, Laurencia intricata and Laurencia spp. red algae were identified. The $100\%$ RAE was able to totally inhibit the egg hatch, showing an efficacy comparable \((P < 0.05)\) to that of the reference drug \((98.7%)\). An egg hatch reduction of \(89.5, 43.7\), and \(23.4%\) was observed at \(50, 5\) and \(1%\) dilutions, respectively. In conclusion, RAE was able to inhibit the egg hatch of GIN of donkeys in a concentration-dependent manner with a correlation coefficient \((R2)\) of $0.968$, corroborating with its anthelmintic effect.
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A model of dual latency compartments for the transmission dynamics of COVID-19 in Oyo state, Nigeria

EASL-Vol. 4 (2021), Issue 1, pp. 1 – 13 Open Access Full-Text PDF
O. Adedire, J. N. Ndam
Abstract: In this study, a mathematical model of dual latency compartments is developed to investigate the transmission dynamics of COVID-19 epidemic in Oyo state, Nigeria. The model consists of non-pharmaceutical control strategies which include the use of face masks, social-distancing and impact of mass-media on the spread of novel coronavirus in the state. Results indicate control reproduction number \(R_C = 1.4\) with possibilities of high constructive influence of mass-media. Thus, at the fitted values of \(\sigma _f = 0.1,\; \sigma _d = 0.1,\;\sigma _m = 0.6\), the peak of the COVID-19 epidemic is attained after 59,217 infectious quarantined individuals and 328,440 infectious but not quarantined individuals have contracted COVID-19 in about 439 and 443 days respectively from the date of the first incidence. Therefore, efforts on mass-media with programs that can inform the people on effective use of face masks, social-distancing and other safety measures can aid reduction of reproduction number to a value below 1 necessary for eradication of the disease.
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Super cyclic antimagic covering for some families of graphs

OMS-Vol. 5 (2021), Issue 1, pp. 27 – 33 Open Access Full-Text PDF
Muhammad Numan, Saad Ihsan Butt, Amir Taimur
Abstract: Graph labeling plays an important role in different branches of sciences. It gives useable information in the study of radar, missile and rocket theory. In scheme theory, coding theory and computer networking graph labeling is widely employed. In the present paper, we find necessary conditions for the octagonal planner map and multiple wheel graph to be super cyclic antimagic cover and then discuss their super cyclic antimagic covering.
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