Comparative Analysis of Selected Animal and Vegetable Oils Suitability in Machining of Plain Carbon Steels

Due to the alarming rate in public awareness on environmental issues, there has been growing demand for biodegradable materials which has opened an avenue for using vegetable and animal oils as alternatives to petroleumbased polymeric materials in the market, most especially in machining operations. Thus, research on biodegradable functional fluids has emerged as one of the top priorities in lubrication, due to their applicability in many diverse areas. In this quest, there is need to conduct machining trials to determine the suitability of these oils in metal cutting (turning) operations of plain carbon steels. This study investigate the effect of the selected cutting fluids on certain parameters like machine removal rate (MRR), machining time, tool wear and spindle power consumption, etc. under different machining combination in turning operations of plain carbon steels obtained from universal steel Ikeja, Nigeria, using 150 x 10 HSS cutting tool. The selected oils purchased from Ogunpa market in Ibadan, Nigeria, were sieved to remove any foreign particles or dirt. The solution; water, based-oil, and emulsifier (to allow thorough mixing of water and oil without separation), were mix at an elevated temperature of 550C in a proportion 4:1:3. Experimental results clearly showed that Conventional cutting fluid might be replaced with Non-conventional cutting fluids (vegetable and animal based) as they give better performance. With slight modifications and deliberate but careful alterations in some of the components of such oils, even better performing cutting fluids could be obtained.Self-sponsore

Comparative Analysis of Selected Animal and Vegetable Oils Suitability in Machining of Plain Carbon Steels

Due to the alarming rate in public awareness on environmental issues, there has been growing demand for biodegradable materials which has opened an avenue for using vegetable and animal oils as alternatives to petroleum-based polymeric materials in the market, most especially in machining operations. Thus, research on biodegradable functional fluids has emerged as one of the top priorities in lubrication, due to their applicability in many diverse areas. In this quest, there is need to conduct machining trials to determine the suitability of these oils in metal cutting (turning) operations of plain carbon steels. This study investigate the effect of the selected cutting fluids on certain parameters like machine removal rate (MRR), machining time, tool wear and spindle power consumption, etc. under different machining combination in turning operations of plain carbon steels obtained from universal steel Ikeja, Nigeria, using 150 x 10 HSS cutting tool. The selected oils purchased from Ogunpa market in Ibadan, Nigeria, were sieved to remove any foreign particles or dirt. The solution; water, based-oil, and emulsifier (to allow thorough mixing of water and oil without separation), were mix at an elevated temperature of 550C in a proportion 4:1:3. Experimental results clearly showed that Conventional cutting fluid might be replaced with Non-conventional cutting fluids (vegetable and animal based) as they give better performance. With slight modifications and deliberate but careful alterations in some of the components of such oils, even better performing cutting fluids could be obtained

Development of an Indigenously Made Diesel Fired Crucible Furnace

Most castings in Nigeria are imported, the poor performance of the manufacturing sector in Nigeria is indicative of the low state of the foundry industry of which majority are small–medium scale enterprises with an unsubstantial total productive cost and input to the upper limit of only between 5-20 million naira. This is quite very low compared to that in the US; put the market value of the annual casting shipments at 28-30 billion US dollars produced by approximately 3,200 foundries has been reported. These myriad of problems therefore, necessitated this research workThe technological advancement of any nation have been influenced and uplifted by the extent to which it can usefully harness and convert its mineral resources. The productions of metal in foundries and in all human lives have become a general practice. This work deals with the design, fabrication and performance evaluation of a diesel-fired crucible furnace suitable for use both in the rural and urban areas for casting of different types of metals using indigenously sourced materials and technology. The components of furnace were furnace casing, crucible, furnace cover, burner housing, furnace cover stand, base stand and burner. Mild steel sheet was used for the fabrication of the furnace, while the other components needed for the design were selected based on functionality, durability, cost and local availability. Experimental tests were performed to evaluate the performance of the furnace. The average heating rate of 19.54°C/min was recorded by the furnace and attained a temperature as high as 1420 °C. The furnace also had a melting rate of 454.55g/min for Aluminium. The thermal efficiency of the furnace was determined to be 10.80%. The low value was as result of the large energy wastage due to the type of insulator used in making the furnace wall. The furnace is environmental friendly without health hazards to the workers and can be moved from one place to another unlike the local one.Self-sponsore

Moringa Regimen Corrects Nicotine-induced Deficits in Behaviour, Altered Energy Metabolism and Neurotransmitter Processing in Rat Brain

Background: Nicotine is the addictive component of tobacco smoking. It has been reported to have a negative neuromodulatory role in the CNS. Moringa oleifera is a medicinal plant with reported antioxidant, anticonvulsant, anti-inflammatory and neuroprotective properties. Aim and Objectives: This study was purposed to investigate the neuronal adaptation potentials of Moringa Oleifera (MO) on nicotine induced behavioural decline and perturbed bioenergetics. Material and Methods: Twenty-four adult male Wistar rats were used. The treatment regimen was as follows; control group received distilled water, MO group received 200 mg/kg of MO, Nicotine Group received 1.38 mg/kg body weight of nicotine, and Nicotine + MO group received combined treatment of 200 mg/kg body weight of MO after 1.38 mg/kg body weight of nicotine for 28 days. The animals were subjected to Morris water maze for spatial memory, Y maze for working memory and elevated-plus maze tests for anxiety levels after which they were sacrificed for spectrophotometric analysis of global protein expression, neural bioenergetics (lactate dehydrogenase and glucose-6-phosphate dehydrogenase), and Acetylcholinesterase (AChE) levels. Results: Nicotine infusion caused a reduction in the escape latency period, increased the percentage incorrect alternation, and elevated the anxiety levels of rats. These observations were indicative of decreased synaptic activity in the brain. Together with, nicotine induced chromatolytic changes in cells of the frontal cortex and hippocampus. Co-administration with MO prevented nicotine-associated memory decline, perturbed glucose bioenergetics, induced chromatolysis and histomorphological distortion in the frontal cortex and hippocampus. Conclusion: Our data demonstrate that MO administration enhances experience-dependent neuroplasticity and cognitive behaviour function in laboratory animals, modulates energy metabolism and reduced oxidant stress possibly through enhanced production of key antioxidant enzymes against the damaging effects of nicotine. It provided evidence that MO can be further developed as a means to protect the brain from oxidative stress-induced injury

MasakhaNEWS: News Topic Classification for African languages

African languages are severely under-represented in NLP research due to lack of datasets covering several NLP tasks. While there are individual language specific datasets that are being expanded to different tasks, only a handful of NLP tasks (e.g. named entity recognition and machine translation) have standardized benchmark datasets covering several geographical and typologically-diverse African languages. In this paper, we develop MasakhaNEWS -- a new benchmark dataset for news topic classification covering 16 languages widely spoken in Africa. We provide an evaluation of baseline models by training classical machine learning models and fine-tuning several language models. Furthermore, we explore several alternatives to full fine-tuning of language models that are better suited for zero-shot and few-shot learning such as cross-lingual parameter-efficient fine-tuning (like MAD-X), pattern exploiting training (PET), prompting language models (like ChatGPT), and prompt-free sentence transformer fine-tuning (SetFit and Cohere Embedding API). Our evaluation in zero-shot setting shows the potential of prompting ChatGPT for news topic classification in low-resource African languages, achieving an average performance of 70 F1 points without leveraging additional supervision like MAD-X. In few-shot setting, we show that with as little as 10 examples per label, we achieved more than 90\% (i.e. 86.0 F1 points) of the performance of full supervised training (92.6 F1 points) leveraging the PET approach.Comment: Accepted to IJCNLP-AACL 2023 (main conference

MasakhaNEWS:News Topic Classification for African languages

African languages are severely under-represented in NLP research due to lack of datasets covering several NLP tasks. While there are individual language specific datasets that are being expanded to different tasks, only a handful of NLP tasks (e.g. named entity recognition and machine translation) have standardized benchmark datasets covering several geographical and typologically-diverse African languages. In this paper, we develop MasakhaNEWS -- a new benchmark dataset for news topic classification covering 16 languages widely spoken in Africa. We provide an evaluation of baseline models by training classical machine learning models and fine-tuning several language models. Furthermore, we explore several alternatives to full fine-tuning of language models that are better suited for zero-shot and few-shot learning such as cross-lingual parameter-efficient fine-tuning (like MAD-X), pattern exploiting training (PET), prompting language models (like ChatGPT), and prompt-free sentence transformer fine-tuning (SetFit and Cohere Embedding API). Our evaluation in zero-shot setting shows the potential of prompting ChatGPT for news topic classification in low-resource African languages, achieving an average performance of 70 F1 points without leveraging additional supervision like MAD-X. In few-shot setting, we show that with as little as 10 examples per label, we achieved more than 90\% (i.e. 86.0 F1 points) of the performance of full supervised training (92.6 F1 points) leveraging the PET approach

Hybridization of Machine Learning Techniques in Predicting Mental Disorder

This study applied a hybrid Random Forest and Artificial Neural Network (RF-ANN) model in predicting the chances of IT employees developing mental disorder. To measure the performance of the model, Random Forest and Artificial Neural Networks algorithms were separately developed, their results were recorded and compared with the results of the hybridized model. The result obtained from the hybridized model showed a significant improvement in its performance over the individual performances of the Random Forest model and Artificial Neural Networks models. Hybridizing Random Forest and Artificial Neural Networks using “Bagging Ensemble” produced a model that was able to correctly predict the chances of IT employees developing Mental Disorder with 94% recall and 80% F1-score compared to 65% and 60% respectively in the Random Forest Model. With these results, applying the RF-ANN model on improved dataset could be investigated and compared with the results found in this study

Comparative effects of coconut water and N-Acetyl cysteine on the hypothalamo-pituitary-gonadal axis of male rats

Coconut water (CW) contains cysteine, an amino acid which influences glutathione metabolism and promotes reproductive functions. The effects of CW and N-acetyl cysteine (NAC) were compared on the hypothalamo-pituitary-gonadal-axis of danazol-(a GnRH antagonist)-treated rats. Seven groups of male rats were treated orally for six weeks as follows; 1: 20 mL/kg distilled water (Control); 2: 20 mL/kg Corn oil; 3: 20 mL/kg CW; 4: 100 mg/kg NAC; 5: 200 mg/kg Danazol; 6: Danazol+CW; 7: Danazol+NAC. Serum gonadotropins and testosterone; sperm indices; testicular malondialdehyde and glutathione were determined. Sperm quality increased in groups 3, 4, 6 and 7, and reduced in group 5 compared with groups 1 and 2. Gonadotropins and testosterone increased in groups 6 and 7 compared with group 5. Malondialdehyde reduced, while glutathione increased, in groups 3 and 4 compared with group 1. These similarities suggest that cysteine contributes to the effects of coconut water along the hypothalamo-pituitary-gonadal-axis