938 research outputs found
Performance Analysis of Best Relaying Protocol Selection with Interferences at Relays
In this paper, we investigate the performance of selecting the best protocol between amplify and forward (AF) and decode and forward (DF) in multiple relay networks with multiple interferences at relays. In the selection scheme, the best protocol between AF and DF is selected depending on the comparisons of signal-to-interference and noise ratio (SINR) for all source-relay links. All relays measure the received SINR to decide forwarding signal or not. When SINR is above a certain threshold then DF is used otherwise AF is used. Particularly, we develop an accurate mathematical model for best relaying protocol by considering the effect of interferences to our scheme. Firstly, we derive the asymptotic closed form expression for the symbol error rate (SER) for the system under study. Also we derive an upper and lower bound of symbol error rate and show how they were tight with exact SER. Furthermore an approximate expression for the outage probability is derived. Numerical results are finally presented to validate the theoretical analysis with a different number of relays
Infinite integral conditions for oscilation of first order linear delay differential equations with positive and negative coefficients
This study obtains a new set of integral conditions for oscillation of nonautonomous delay differential equations with positive and negative coefficients. It is however, discovered that every solution of the equation oscillates infinitely.Keywords: Integral Condition, Oscillation, Positive and Negative Coefficient
Evaluation of Growth Performance of Tomato in Response to Biochar and Arbuscular Mycorrhizal Fungi (Amf) Inoculation
Field experiment was conducted in 2013 and 2014 to evaluate growth performance of two tomato genotypes in response to biochar application and arbuscular mycorrhizal fungal (AMF) inoculation at the Teaching and Research Farm, Federal University of Agriculture, Abeokuta. The experiment was laid out in a split-split plot design with two tomato genotypes in the main plots, five levels of biochar application in the sub plots and two levels of AMF inoculation in the sub-sub plots. Data on plant height number of leaves and dry matter yields were generated and subjected to analysis of variance and significant means separated using Duncanâs Multiple Range Test at 5 % level of significance. The result shows that mycorrhizal inoculation significantly increased (p< 0.05) the shoot dry matter yield (2935.8 kg ha-1) when compared with non-mycorrhizal plants, there is no significant difference in number of leaves, height and root dry matter yield. Application of 20 t ha-1 of biochar significantly increased (p< 0.05) the shoot dry matter yields and plant height while no significant differences were observed in number of leaves and root dry matter yield. From the results obtained it can be concluded that AMF can successfully be inoculated into biochar amended soil to improve the performance of tomato plant.Keywords: Biochar; AMF; inoculation; tomato; growth performance
POLA PERTUMBUHAN DAN UKURAN PERTAMA KALI TERTANGKAP IKAN CAKALANG YANG DIDARATKAN DI PELABUHAN PERIKANAN NUSANTARA (PPN) AMBON
Tujuan penelitian untuk mendiskripsikan dan menganalisis produksi, distribusi ukuran, pola pertumbuhan dan ukuran pertama kali tertangkap Ikan cakalang (Katsuwonus pelamis) yang didaratkan di pelabuhan perikanan nusantara PPN Ambon. Hasil penelitian menunjukkan bahwa produksi hasil tangkapan armada pancing tonda dan pukat cincin yang menangkap ikan cakalang dan didaratkan di PPN Ambon selama penelitian berfluktuasi. Ukuran Gross Ton untuk kapal pancing tonda berkisar antara 16-28 GT dan kapal pukat cincin masing-masing berukuran 28 GT dan 99 GT. Distribusi ukuran panjang ikan cakalang antara 28,9-71,5 cmFL dengan bobot 0,108-8,255 kg. Kisaran ukuran panjang ikan yang dominan berada pada kisaran pada 37,0-41,0 cmFL dan 47,0 - 51,0 cmFL. Pola pertumbuhan ikan cakalang di tiga bulan penelitian november, desember, dan januari bersifat allometrik negatif, sedangkan bulan pebruari bersifat allometrik positif. Ukuran panjang pertama kali tertangkap oleh alat tangkap pancing tonda 45,3 cm dan purse seine 51,9 cm
An isolated tuberculousorchitis mimicking testicular tumour as a primary presentation of HIV: a case report
Background: An isolated tuberculousorchitis is a rare lesion and is distinctly unusual as the primary presentation of human immunodeficiency virus (HIV) infection. A high index of suspicion remains decisive to this diagnosis especially when the clinico-radiological findings of such lesion affirmed features of the testiculartumour.Case Report: A 32-year old man presented with a three-months history of left sided painless progressive testicular swelling. Further clinico-radiological findings revealed traits of a left testicular tumour. He was found to be HIV positive only at the index presentation whilst the histopathology of the left sided orchidectomy tissue confirmed tuberculous (TB) orchitis.Conclusion: High index of suspicion for TB orchitis with HIV in a patient with clinico-radiological findings of the testicular tumour from areas with high HIV and TB prevalence help in an expeditious diagnosis and therapy.Keywords: Tuberculosis, tuberculous orchitis, testicular tumou
Economics of Groundnut Production among Smallholder Farmers in Michika Local Government Area of Adamawa State, Nigeria
This study assessed economics of groundnut production among smallholder farmers in Michika local government area of Adamawa State, Nigeria. Multistage sampling technique which involves purposive selection of Michika and simple random selection of farmers from eight wards was embraced in collecting primary data from 172 farmers using structured questionnaire. The analytical tools used were mainly descriptive, gross margin and regression analysis. The analysis found that groundnut production is profitable with an average gross margin of N97,477.80, total revenue of N167,160, and net farm income of N 94,540.64 per hectare. The regression analysis indicated that Cobb-Douglas production function gave the best fit with R2 value of 0.748, implying that the specified factor inputs in the regression equation explained up to 74.8% of the variation in groundnut output and only 25.2% was accounted for by the random error term. Production inputs such as farm size, labour, agrochemicals, seeds and farming experience were statistically significant at varying levels of probability. This means that any increase in such inputs would bring about increase in groundnut output. Resource use efficiency analyses indicate that the ratios of MVP and MFC in respect to seeds, labour and Agrochemicals were greater than unity and hence were under-utilized by the farmers during production period. Therefore, policies aimed at assigning more production inputs to farmers should be introduce by government in order to enhance farmers\u27 output and profitability
Stacking tolerance to drought and resistance to a parasitic weed in tropical hybrid maize for enhancing resilience to stress combinations
Open Access JournalMaize is a food security crop cultivated in the African savannas that are vulnerable to the occurrence of drought stress and Striga hermonthica infestation. The co-occurrence of these stresses can severely damage crop growth and productivity of maize. Until recently, maize breeding in International Institute of Tropical Agriculture (IITA) has focused on the development of either drought tolerant or S. hermonthica resistant germplasm using independent screening protocols. The present study was therefore conducted to examine the extent to which maize hybrids simultaneously expressing resistance to S. hermonthica and tolerance to drought (DTSTR) could be developed through sequential selection of parental lines using the two screening protocols. Regional trials involving 77 DTSTR and 22 commercial benchmark hybrids (STR and non-DTSTR) were then conducted under Striga-infested and non-infested conditions, managed drought stress and fully irrigated conditions as well as in multiple rainfed environments for 5 years. The observed yield reductions of 61% under managed drought stress and 23% under Striga-infestation created desirable stress levels leading to the detection of significant differences in grain yield among hybrids at individual stress and non-stress conditions. On average, the DTSTR hybrids out-yielded the STR and non-DTSTR commercial hybrids by 13â19% under managed drought stress and fully irrigated conditions and by â4 to 70% under Striga-infested and non-infested conditions. Among the DTSTR hybrids included in the regional trials, 33 were high yielders with better adaptability across environments under all stressful and non-stressful testing conditions. Twenty-four of the 33 DTSTR hybrids also yielded well across diverse rainfed environments. The genetic correlations of grain yield under managed drought stress with yield under Striga-infestation and multiple rainfed environments were 0.51 and 0.57, respectively. Also, a genetic correlation between yields under Striga-infestation with that recorded in multiple rainfed environments was 0.58. These results suggest that the sequential selection scheme offers an opportunity to accumulate desirable stress-related traits in parents contributing to superior agronomic performance in hybrids across stressful and diverse rainfed field environments that are commonly encountered in the tropical savannas of Africa
Phytochemical Screening and Preliminary Evaluation of Analgesic and Anti-Inflammatory Activities of the Methanol Root Extract of Cissus Polyantha
Cissus polyantha is used in traditional medicine for the treatment of conjunctivitis and inflammation. In this study, the methanolic root extract of Cissus polyantha was subjected to preliminary phytochemical screening, analgesic and anti-inflammatory studies. Phytochemical studies was carried out using standard phytochemical protocol while the analgesic studies was carried out using acetic acid-induced writhing tests in mice. Carrageenan-induced hind paw oedema in rats was used to evaluate the anti-inflammatory potential of the extract. Phytochemical studies of the methanolic crude root extract of the plant revealed the presence of carbohydrates, flavonoids, saponins, tannins steroids and triterpenes. The extract at doses of 20, 40 and 80 mg/kg, i.p significantly (P < 0.05) decreased the acetic-acid induced writhing. The extract also produced significant (P < 0.05) and dose-independent anti-inflammatory activity comparable to that of reference drug, ketoprofen. The intraperitoneal lethal dose (LD 50) toxicity studies on the methanol crude root extract of the plant was found to be 288.53 mg/kg body weight. These findings are suggestive of the analgesic and anti-inflammatory potentials of the methanol root bark extract of the plant and provide a scientific rationale for the use of the root of Cissus polyantha in traditional medicine.Keywords: Cissus polyantha, Phytochemical screening Analgesic, Anti-inflammatory, traditiona
Optimization of Crystal Violet dye removal from aqueous solution using agro wastes
Batch adsorption process involving use of groundnut shell (GS) and orange peel (OP) as adsorbents was employed for the removal of carcinogenic Crystal Violet dye from aqueous solution. Studies were carried out as function of contact time, sorbent dosage, initial dye concentration and pÎ of the dye solution with a view of optimizing adsorption conditions. The results obtained showed high efficiency of â 98.3% and 97% using 4.5g of GS and OP respectively, showing a promising performance of the agro wastes as filters for the dye removal.Keywords: Crystal violet, Groundnut shell, Orange peel, % Removal, Adsorptio
Influence of Guidance and Counseling on Choice of Business Subjects Among Secondary School Students in Gombe State
This study investigated the influence of guidance and counseling on choice of business subjects among secondary school students in Gombe state. Two specific objectives, two research questions and two null hypotheses were raised. Survey research design was adopted for the study. The population of the study was 21,465 secondary school students and 377 of them were randomly used for the study. Four rating scale structured questionnaire titled Choice of Business Subjects among Students (CVSS) constructed by the researcher were used for data collection. Data collected were analyzed using benchmark score of 2.5 and above for agree while simple logistic regression was employed in the test of the two null hypotheses at 0.05 alpha level of significance. The study revealed among others that guidance and counseling has influence on choice of business subjects among secondary school students in Gombe state. In addition in contributed on gender disparity of students choice in business subjects. The resultant effect is that most secondary school students perceived that business subjects are either meant for academic misfits or female students. Based on the outcome of the study, the researcher recommended among others that teachers, especially those counseling students should help to instill in students the positive attitude towards business subjects, this will develop in them interest and choice of business subjects at secondary school level. Keywords: - Guidance, Counseling , Choice, Business, Subjects, Students. DOI: 10.7176/RHSS/9-12-20 Publication date:June 30th 201
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