368 research outputs found

    Impact of the Nozzle Angles on Counterflow Diffusion Flame to Strain Rate Variations

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    The Diffusion laminar combustion of liquefied petroleum gas (LPG) and air is studied experimentally using counterflowing axisymmetric jets. Attributes of this type of burner arrangement for studying laminar combustion are discussed in terms of flame geometry, angle of nozzle, strain rate, and measurement access. In the current research, an integrated combustion system was designed and developed for a type of counterflow diffusion flame. To study formation of the disc flame and the limits of stability, three types of nozzle with different angles (30°, 45°, and 60°) were used, an integrated design of two perpendicular burners was made to maintain the temperature of the mixture constant before the reaction. In the current study the charts of flame stability of diffusion flame with different equivalence ratios (0.65≤ ϕ ≥1.45) are obtained , and determine the limits of temperature distribution and strain rate

    Incidence of Diabetes mellitus at the Federal Medical Centre Katsina, Katsina State, Nigeria: A Retrospective Study

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    A six-year (2002 – 2007) retrospective study of hospital records (in-patients) was carried out to investigate the incidence of Diabetes Mellitus in Katsina. The records showed that a total of 754 cases were attended within the study period. The study showed yearly increase in the incidence of the disease with the highest incidence of 288 (38.20%) in the year 2007 and the least 65 (8.62%) in the year 2002. More males suffered from the disease 456 (60.48%) than females 298 (39.52%). The incidence was also found to be high 289 (38.33%) in the age range 65 and above, while age range 25 – 34 was least affected 28 (3.71%). Ways on how to live free of Diabetes Mellitus were also recommended.Keywords: Age Range, Diabetes Mellitus, Incidence, Hospita

    Seasonal variations in the proximate compositions of five economically- important fish species from Lake Victoria and Lake Tanganyika, Tanzania

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    Proximate compositions of five economically-important fish species from Lake Victoria and Lake Tanganyika, Tanzania were determined using standard methods and procedures of the Association of the Analytical Chemists. Samples of Lates niloticus, Oreochromis niloticus, Rastrineobola argentea, Limnothrissa miodon and Stolothrissa tanganicae were collected during the dry and rainy seasons (December 2012 to March 2013) and (June to September, 2013). Protein contents (17.35- 21.44 g/100 g) were significantly (p<0.05) higher in wet seasons and lower (16.13 -19.77 g/100 g) during the dry season in all the species. Similarly, lipids contents were significantly (p<0.05) higher during the wet seasons (1.01 – 3.19 g/100 g) and lower (0.79 -1.79 g/100 g) during the dry season in all the species, while carbohydrate (1.89 - 4.46 g/100 g) was significantly (p<0.05) higher during the dry season in all the species. The present study showed that these species are good sources of protein in desirable quantities for normal growth, development and as a remedy to nutritional and health related problems. High contents of protein and lipid during wet season make the fish species desirable for consumption during this period. These fish species are therefore recommended to diabetic consumers due to their low carbohydrate contents.Key words: Fish species, Lake Victoria, Lake Tanganyika, Proximate, Seasonal variations

    Effectiveness of firefly algorithm based neural network in time series forecasting

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    Global optimization techniques such as Particle Swarm Optimizers (PSO) and Genetic Algorithm (GA) are now widely used for training Artificial Neural Networks (NN), particularly in time series forecasting problems. Firefly algorithm (FA) is a relatively new addition to the family of population based optimization technique that has shown promising result in a number of problems. In this work, we evaluate the effectiveness of FA trained NN in time series forecasting. In the experiments, three well known time series were used to evaluate the performance. Results obtained were compared with results from both PSO and Resilient Propagation (RPROP) trained NNs. FA based NN performed very well in forecasting all the time series considered, outperforming the bench-marks in two out of the three problems.Keywords: Time series, Artificial Neural Network, Firefly Algorithm, Particle Swarm Optimization, Overfittin

    Description of soft sediment deformational structure of the Campano-Maastrichtian Gombe formation of the Northern Benue Trough, N.E. Nigeria

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    Several soft sediment deformational structures were identified during fieldwork survey carried out on exposures of Gombe Formation in the Gongola sub–basin of the Northern Benue Trough at Gombe and environs. These soft sediment deformational structures includes: simple internal cusps, which occur wide spread across a single bed or  intermittently across several beds, and slump structures that are represented by complex recumbent folds and concave upwards structures. These structures are proxy to syn-depositional energy operating within the depositional environment and this current research aims to evaluate their trigger mechanism. These deformational structures are commonly hosted in the mouth-bar deltaic sequences of the Gombe Formation. The deltaic setting is usually a locus for high sediment influx and accumulation. This may have generated high quantum of depositional energy which was probably responsible for the development of the syn-depositional soft sediment depositional structures in the Gombe Formation during Campano-Maastrichtian times. KEYWORDS: Gombe, Sandstone, Gongola Basin, soft sediment Benue trough

    Lunasin and Bowman-Birk Protease Inhibitor Concentrations of Protein Extracts from Enzyme-Assisted Aqueous Extraction of Soybeans

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    Lunasin and Bowman-Birk protease inhibitor (BBI) are two soybean peptides to which health-promoting properties have been attributed. Concentrations of these peptides were determined in skim fractions produced by enzyme-assisted aqueous extraction processing (EAEP) of extruded full-fat soybean flakes (an alternative to extracting oil from soybeans with hexane) and compared with similar extracts from hexane-defatted soybean meal. Oil and protein were extracted by using countercurrent twostage EAEP of soybeans at 1:6 solids-to-liquid ratio, 50C, pH 9.0, and 120 rpm for 1 h. Protein-rich skim fractions were produced from extruded full-fat soybean flakes using different enzyme strategies in EAEP: 0.5% protease (wt/g extruded flakes) used in both extraction stages; 0.5% protease used only in the second extraction stage; no enzyme used in either extraction stage. Countercurrent two-stage protein extraction of air-desolventized, hexane-defatted soybean flakes was used as a control. Protein extraction yields increased from 66% to 89-96% when using countercurrent two-stage EAEP with extruded full-fat flakes compared to 85% when using countercurrent two-stage protein extraction of air-desolventized, hexane-defatted soybean flakes. Extruding full-fat soybean flakes reduced BBI activity. Enzymatic hydrolysis reduced BBI contents of EAEP skims. Lunasin, however, was more resistant to both enzymatic hydrolysis and heat denaturation. Although using enzymes in both EAEP extraction stages yielded the highest protein and oil extractions, reducing enzyme use to only the second stage preserved much of the BBI and Lunasin

    Perception of Nigerian Cocoa Farmers on Child Labour: Implications for Hazardous Child Labour

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    This paper investigated perception of Nigerian cocoa farmers on Hazardous Child Labour. More importantly, in accordance with International Labour Organisation Child Labour Convention. Accidents, exposure to chemicals, bacteria or viral infection, ergonomically inappropriate tools, child molestation, minimum age requirement, awkward posture, and poor academic performance were identified as farm hazards. Multistage sampling technique was used for the methodology, the selection of study areas, Ondo and Cross-River states was purposive and 240 respondents were randomly selected. Information were solicited by issuance of questionnaires and interview schedule. Data were analysed using percentage, mean, frequency counts, standard deviation, pie chart, bar chart and correlation analysis. The study revealed a mean age of 45.32±8 years and 66.67% of the farmers, who employed children between 5-17 years of which 80% of them were attending secondary schools as labourers. Cocoa farmers (63%) had one form of education which is an indication of being able to read and write. Almost half of the respondents (49.58%) attested that, they can call upon these children, to work at any time on their cocoa farms. Respondents (60.40%) employed only family labour for their farming activities. Population of 50.80% of the respondents held the view that, child labour was part of socialization and 52.50% saw it as a way of building children up for future. Farmers (55.80%) reported that, child labour was a source of cheap labour and 82.50% of respondents had worked on the farm as labourer during their growing up years. It was revealed that, majority of farmers have high awareness and knowledge on hazardous child labour based on the listed farm hazards, however their practice also was high. Correlation analysis showed that, there was positive and significant relationship between perception and practice of hazardous child labor, r = 0.628** (P≤0.01) which indicated that, majority of respondents are still in the practice of exposing children labourers to hazards. It was concluded that, cocoa farmers should change their perception on hazardous child labour, as it negatively affects the physical, psychological and emotional well-being of a children. Furthermore, awareness should be created to educate farmers in the study areas, on definition and why hazardous child labour should be eliminated. This will contributes to households breaking out of the cycle of poverty and the country to advance in human development

    Analysis of sildenafil citrate in herbal aphrodisiac preparations marketed in Sokoto metropolis and its public health implications

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    Aphrodisiacs are among the most widely marketed and consumed herbal products in North-Western Nigeria. There are speculations that these products are being adulterated with orthodox medicines in order to boost their effects and sales. The objective of current research was to analyse the presence of adulterated sildenafil citrate in some herbal aphrodisiacs commonly sold and consumed in Sokoto metropolis. Ten different liquid herbal aphrodisiac preparations marketed in Sokoto metropolis were collected from different areas of the city. Each of the preparation was analysed for adulteration with sildenafil citrate using thin layer chromatography and UV spectroscopy. Five of the preparations were found to contain sildenafil citrate in the range of 34 – 291 mg per daily dose. The findings from this study indicate that some of the herbal aphrodisiac preparations marketed in Sokoto metropolis are being adulterated with substantial amount of undeclared sildenafil citrate, a practice that poses serious public health hazard to its consumers. Consequences of which ranges from nausea, dyspepsia, pain, dizziness, abnormal vision, and headache and potentially heart attack especially among adults with underlying chronic diseases such as hypertension among others

    Cuffless Blood Pressure in clinical practice: challenges, opportunities and current limits.

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    Background: Cuffless blood pressure measurement technologies have attracted significant attention for their potential to transform cardiovascular monitoring.Methods: This updated narrative review thoroughly examines the challenges, opportunities, and limitations associated with the implementation of cuffless blood pressure monitoring systems.Results: Diverse technologies, including photoplethysmography, tonometry, and ECG analysis, enable cuffless blood pressure measurement and are integrated into devices like smartphones and smartwatches. Signal processing emerges as a critical aspect, dictating the accuracy and reliability of readings. Despite its potential, the integration of cuffless technologies into clinical practice faces obstacles, including the need to address concerns related to accuracy, calibration, and standardization across diverse devices and patient populations. The development of robust algorithms to mitigate artifacts and environmental disturbances is essential for extracting clear physiological signals. Based on extensive research, this review emphasizes the necessity for standardized protocols, validation studies, and regulatory frameworks to ensure the reliability and safety of cuffless blood pressure monitoring devices and their implementation in mainstream medical practice. Interdisciplinary collaborations between engineers, clinicians, and regulatory bodies are crucial to address technical, clinical, and regulatory complexities during implementation. In conclusion, while cuffless blood pressure monitoring holds immense potential to transform cardiovascular care. The resolution of existing challenges and the establishment of rigorous standards are imperative for its seamless incorporation into routine clinical practice.Conclusion: The emergence of these new technologies shifts the paradigm of cardiovascular health management, presenting a new possibility for non-invasive continuous and dynamic monitoring. The concept of cuffless blood pressure measurement is viable and more finely tuned devices are expected to enter the market, which could redefine our understanding of blood pressure and hypertension

    Diagnosis and management of COVID toes in outpatients: a case report.

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    Since the beginning of the coronavirus disease 2019 pandemic, the most common skin lesions observed due to infection with the severe acute respiratory syndrome coronavirus 2 are pseudochilblains (or coronavirus disease toes). However, this pathology remains infrequent and difficult to diagnose, as no specific test exists. Two Caucasian women, 30 and 22 years old, presented to our General Medicine Unit with perniosis lesions on the feet during the first two waves of the coronavirus disease 2019 pandemic. They did not have respiratory or general symptoms of severe acute respiratory syndrome coronavirus 2 infection, the reverse transcription polymerase chain reaction on nasopharyngeal swabs was negative, and the serology was positive only in the first case. The clinical presentation differed for the two cases, as the second patient suffered from swelling and burning after cold application. The diagnosis was based on clinical presentation, temporality, exclusion of other differential diagnoses, and blood test results (positive serology in the first case and high level of CXCL13 and VEGF in the second), supported by current literature. Lesions resolved spontaneously in the first patient. The second case was hospitalized for pain management and received corticosteroid therapy with resolution of the symptoms. These two cases with different clinical presentations illustrate the diagnostic approach to coronavirus disease 2019, a challenging disease with diverse manifestations, including, in some cases, coronavirus disease toes. We present a literature review that illustrates the progression of scientific research. Skin lesions associated with coronavirus disease 2019 infection could be the expression of an important interferon type 1 response and should be considered in the differential diagnosis in a primary care setting
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