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Waste to wealth in building materials development: a review of plastic waste in concrete
No full textRecently, there has been a growing interest in the use of post-consumer plastics in the production of concrete. Consequently, a large number of studies reporting the behaviour of concrete containing waste and recycled plastics have been published. These studies have great potential for improving the inherent weakness of concrete, reduction of pressure induced on the environment and creation of employment opportunities for economic development. This paper presents a review of journal publications on the effects of waste and recycled plastic materials on some fresh and hardened properties of concrete. The effects of waste plastic materials on slump, density, compressive strength, tensile/flexural strength and permeability are discussed. It was concluded that Post-consumer plastics can be successfully and effectively utilized to replace conventional concrete. This presents a strong potential for the production of sustainable concrete as well as meeting the goals of sustainable development requiring a waste to resource approach. The study suggests public education and awareness on the prospects of using waste plastic in concrete for economic empowerment among the population
Solid waste generation and characterization in Ilorin, Nigeria
No full textGlobal per capita waste generation rates and characterization vary by regions, countries, and within cities. The generation, l and characterization of waste from selected areas in Ilorin, Nigeria, prone to indiscriminate disposal of solid waste without consequence were analyzed for proper management. Municipal solid wastes were sorted, analyzed by weight and percentage composition using the quantitative approach. The average generated waste per capita was estimated to be 0.66 kg/day, w/w distribution was 57.53% food waste, 9.07% nylon (flexible films), 5.98% plastic (rigid containers),4.95% textile, 10.51% paper and 11.96% others. The average moisture content was 46.16% food waste, 20.63% nylon, 18.65% plastic, 36.67% textile, 18.45% paper and 42.89% others. The results show an average bulk density of 10.36 Kg/m3 of food waste, 2.14 of nylon, 0.5 of plastic; 0.93 of textile; 2.74 of paper and others 5.36. The chemical analysis showed that volatile matter ranged from 20.55 to 24.10%, ash content 3.10to 3.90%, fixed carbon 7.5to 9.8%, calorific value 14820to 18360 (kJ/kg), nitrogen 0.40to 0.50%, hydrogen 4.38to 5.80%, carbon 40.90 to 44.30%, oxygen 30.80 to 34.60%, Sulphur 0.19 to 0.24%, fusing point of ash 3.12to 4.38 °C, and heating value from 13.520to 13.64 KJ/Kg. The results generated could play a positive role in the management of solid waste in that area
Characterization of Soils in East And West Zones of Kano River Irrigation Project, Nigeria
No full textThe relationship between clay composition and on organic matter content, Saturated Hydraulic Conductivity, bulk density and location of soils in a different part of the Kano River Irrigation Project (KRIP) was studied by taking soil samples from forty (40) sectors. Sampling was done from the depth of 0-45 cm with soil auger, digger, a wooden plank and core samplers. Particles size analysis has shown that the percentage of clay varies from the range of 22.12% to 5.4% as observed in Raje and Butalawa respectively. The texture in most of the sectors was dominated by sandy loam. The organic matter (OM) content is typical of agricultural topsoil as all the sectors have organic matter within the range of 1–6%. Spearman correlation coefficient of 0.452 indicates that the relationship between % clay and Bulk density was more of a non-linear relationship than linear. The Pearson correlation coefficient of 0.876 between % clay content of the soil in all the sectors and saturated hydraulic conductivity represents a strong negative relationship between the variables, as % clay content increases, the strength of Sat. hydraulic conductivity tends to decrease. The % clay has no relationship with location of sectors based on the correlation analysis. The Pearson and Spearman coefficients between % Clay content and % OM were 0.407 and 0.473 respectively and this represent a positive relationship between the variables. It was recommended that organic matter content, saturated hydraulic conductivity and bulk density can be used as one of the determinant variables in the development of a model aimed at predicting the % clay of soils in KRIP. Application of organic manure and fertilizer to improve soil productivity and buffering capacity was also recommended due to low organic matter content. 
Influence of extrusion process conditions on the residence time and throughput of a twin-screw extruder using full factorial experimental design
No full textThe effect of extrusion condition on residence time and throughput rate of a twin-screw extruder was investigated using blends of sorghum groundnut and tiger nut in twin-screw extruder SLG65 Model. In this study, a three factor 3-level full factorial experimental design was adopted. The influence of extrusion cooking conditions on both the combine effect and the effect of independent variables were evaluated. The analysis of variance showed that both linear and quadratic were not significant, however, interaction significantly (P<0.05) affect both the residence time and the throughput rate of the extruded. The results revealed that the throughput rate ranged from (0.012-0.040 Kg/s). The highest value was recorded at 100°C barrel temperature, 50:30:20 feed composition for ratios of sorghum groundnut and tiger nut and 18% feed moisture content. While the residence time ranged from (47 - 66.0 S) the highest residence time was obtained at 110°C barrel temperature 50:30:20 ratios of sorghum groundnut and tiger nut and 26 % feed moisture content. The information provided about the residence time and throughput rate of a twin-screw extruder will be used in fabricating an extruder that will be used in producing similar extruded product. The result of the research could be used by intended processors of similar extruded product to explore the possibility of producing similar product by manipulating the processing variables in order to obtain a desired product
Optimisation of cover thickness in tyre-fibre concrete under elevated temperature
No full textFailure of structural elements after fire outbreak is mostly attributed to spalling action. Spalling of concrete is an occurrence which results to decrease in the cross sectional area of the concrete elements, thus decreases the resistances to fire loads. This study, optimized the concrete cover thickness in tyre fibre concrete (TFC), which was subjected to single temperature load according to ISO 834 using graphical method. Three (3) samples were prepared from each series of mix containing tyre fibers of 10 mm width and varying length viz; 0%, 2.5%, 5.0% and 7.5%, using water cement ratio of 0.55. The samples were produced in 100 x 100 x 100mm cubes and tested for compressive strength. However, the cubes were structural modeled using TEDDS 2.0.01 and STAADPro v8i to under temperature load to determine optimum cover thickness through the deflection mode. The cover thickness for tyre-fibre concrete reduced from 25mm to 17.5mm under the same condition with the conventional concrete mixture. This shows that inclusion of tyre-fibre in concrete increases the fire resistance and reduces the cover thickness. It is recommended that tyre-fibre concrete should be used in our daily construction work for more durability
Contextualising change in Nigeria’s leadership question through the film medium: A critical reading of Jeta Amata’s Black November
No full textHowever, change is positive when it is progressive; and negative when it is retrogressive. Over the years, Nigeria, as a country, has been in search of credible, dependable, focused and result-oriented leadership. This explains the need for regular intellectual discourses on the leadership question that the country has been grappling with. There is no arguing the fact that, no matter the personal, educational, psychological, economic, religious and cultural background of a leader, the constitution of his/her power base will have determinate effect on his/her approach to leadership. This is because leadership is all about using people to achieve predetermined group objectives. In fact, the contemporary Nigerian film industry, Nollywood, has become a veritable platform to interrogate the leadership question in Nigeria. Consequently, this study examines Jeta Amata’s Black November, a film that portrays a volatile community in the Niger Delta area of Nigeria ravaged by crude oil exploration and exploitation activities of a multi-national oil company. The people fight against the evil machinations of corrupt government and oil company officials that collude to impoverish them. The submission is that only transparency in the policy actions of leaders, at all levels of governance, will mitigate incessant youth restiveness in oil producing communities. Furthermore, the film medium remains a viable option in managing change in Nigeria’s search for credible political leadership
Nigerian dramatists as change agents: The trajectories in three Nigerian playwrights
No full textThe Nigerian dramatist from the days of colonial invasion has always led in the vanguard for change. Change is one phenomenon whose constancy is as sure as the morning dew. Drama on the other hand is one veritable art form that has championed change for the socio-cultural, economic and political development and good governance of nations. This study sets out to critically evaluate the trajectories of political change in Nigeria vis-à-vis the works of select Nigerian dramatists. Historical and textual analysis are methods of research employed on the works of the three Nigerian dramatists: Wole Soyinka’s Kongi’s Harvest, Femi Osofisan’s Once Upon Four Robbers and Emeka Nwabueze’s A Parliament of Vultures. This paper concludes with the view that against all odds, Nigerian dramatists leveraging on their artistic medium have chronicled political change in anticipation for good governance over the years in Nigeria. This has not abated even in the present democratic dispensation as they have continued to influence change especially serving as voices to the downtrodden in the society, thereby entrenching the functions of drama, which are not only to entertain, educate, enlighten, but also to mobilize the masses against undemocratic policies. The paper concludes that change, whether attitudinal or psychological, must first be politically induced for every other change to fall in place
Concordance entre la classification BI-RADS échographique et mammographique dans la prédiction de la malignité des masses mammaires au centre hospitalo-universitaire du Point « G »: Concordance between BI-RADS classification on ultrasonography and mammography in predicting the malignant of breast masses at University Hospital Center Point "G"
No full textObjectif : Evaluer la concordance de la classification BI-RADS échographique mammographique dans la prédiction de la malignité des masses mammaires en comparaison à l’histologie.Méthodologie: Etude transversale descriptive réalisée au service de radiologie du CHU du Point « G » de Bamako (Mali) de décembre 2016 à octobre 2017. Elle portait sur 105 lésions mammaires explorées à l’échographie et à la mammographie avec preuve histologique après biopsie écho-guidée. Les classifications ACR du couple échographie-mammographie ont été confrontées aux résultats d’anatomie pathologique de 105 lésions mammaires pour déterminer les valeurs prédictives.Résultats : 105 lésions mammaires ont été colligées. L’âge moyen était de 37 ans avec des extrêmes de 14 et 66 ans. 71,4% des patientes résidaient à Bamako. Les tumeurs étaient malignes dans 61,9%. Dans 7,6% (n=8) on trouvait un antécédent familial de cancer du sein. La lésion siégeait au sein droit et le QSE droit respectivement dans 55,2% et 33,3%. A l’imagerie, 36 lésions étaient classées ACR2, 2 lésions ACR3, 37 lésions ACR4 et 30 lésions ACR5. Sur 36 lésions classées ACR2, l’histologie a confirmé la bénignité dans 34 cas avec 2 lésions malignes soit une valeur prédictive positive (VPP) de 93,10% à l’échographie et 100% à la mammographie. Les 2 lésions ACR3 avaient une cytologie bénigne. Il y avait une discordance cyto-mammo-échographique dans 3 cas parmi les 37 lésions classées ACR4 (VPP de 81,82% pour l’échographie et 96,77% pour la mammographie). Toutes les lésions mammaires ACR5 étaient malignes à l’exception d’un cas. Un lien statistiquement significatif (p=0001) entre la taille des lésions à l’imagerie mammaire et la malignité à l’histologie et entre l’âge des patientes et le résultat de la cytologie était décelé.Conclusion : L’échographie et la mammographie ont une valeur prédictive positive élevée dans la différenciation entre masses bénignes et malignes du sein. Un lien statistiquement significatif existe entre la taille des lésions à l’imagerie mammaire et la malignité à l’histologie et entre l’âge des patientes et le résultat de la cytologie.
Objective: To evaluate concordance between the BI-RADS of ultrasonography andp mammography in predicting the malignancy of breast masses compare to the histopathology.Methodology: Cross-sectional descriptive study carried out at the radiology department of the Point "G" Medical Center in Bamako (Mali) from December 2016 to October 2017. It involved 105 breast lesions explored by ultrasound and mammography with histological evidence after ultrasound-guided biopsy. The variables studied were the age and pass-history of the patients, the size and the ACR classification of the masses and the pathology result.Results: 105 breast lesions were included. The average age was 37 years old with extremes of 14 and 66 years old. 71.4% of patients resided in Bamako. Malignant tumors were observed in 61.9% of cases. In 7.6% (n = 8) there was a family history of breast cancer. The right breast and the supero-external quadrant were involved in respectively 55.2% and 33.3%. On imaging, there were 36 lesions classified ACR2, 2 lesions ACR3, 37 lesions ACR4 and 30 lesions ACR5. Out of 36 lesions classified ACR2, the histology found 2 malignant lesions, ie a positive predictive value (PPV) of 93.10% on ultrasound and 100% on mammography. The 2 ACR3 lesions had benign cytology. There was a cyto-mammo-ultrasound discordance in 3 cases among the 37 lesions classified as ACR4 (81.82% PPV for ultrasound and 96.77% for mammography). All of the ACR5 breast lesions were malignant except for one. A statistically significant association (p = 0001) between the size of the lesions on breast imaging and malignancy on the histology and between the age of the patients and the result of the cytology was detected.Conclusion: Ultrasonography and mammography have high positive predictive value in differentiating between malignant and benign breast masses compared to histopathology. A statistically significant link exists between the size of the lesions at the malignancy at the histology
Aspects radiologiques des séquelles de tuberculose thoracique de l’adulte au service de pneumo-phtisiologie de l’hôpital national Ignace Deen: Radiological aspects of thoracic tuberculosis sequellae in adults at the pneumophtisiology department of Ignace Deen national hospital
No full textObjectifs : décrire le profil sociodémographique des patients et les séquelles radiologiques de la tuberculose thoracique de l’adulte.Matériels et Méthodes : étude transversale, descriptive de 12 mois incluant 103 patients anciens tuberculeux traités et déclarés guéris, reçus en consultation ou en hospitalisation au service de Pneumo Phtisiologie de l’Hôpital National Ignace Deen du CHU de Conakry, présentant des séquelles à la radiographie standard et/ou au scanner thoracique. Les variables d’études étaient sociodémographiques (âge, sexe, niveau d’instruction, profession et tabagisme), biologique (statut sérologique au VIH) et radiologiques (sequelles thoraciques de la tuberculose).Les données ont étés recueillies sur une fiche d’enquête pré établie et analysées par le logiciel épi info version 3.5.3Résultats : L’âge moyen des patients était de 46,83 ans avec des extrêmes de 21 et 82 ans. La tranche d’âge la plus représentée était celle de 40 à 59 ans soit 48,5%. Il y avait 59,2 % d’hommes (61 sujets) soit un sex-ratio de 1,45. Le tabagisme était présent dans 31,1% des cas et 28,2 % des patients avaient une sérologie VIH positive. A la radiographie thoracique, les opacités rétractiles avec destruction parenchymateuse étaient les lésions les plus fréquentes 44,7% ; suivi des calcifications parenchymateuses 34%, des lésions fibreuses 32 % et les images en grelot 31,1 %. Lésions pleurales étaient représentées par les émoussements des culs de sac pleuraux 21,36 %, les calcifications pleurales 12,60% et les lésions vertébrales de spondylodiscite 4 ,85%. Seulement 8,73 % (9/103) des malades avaient réalisés un scanner thoracique, la lésion scanographique la plus représentée était les cavités à parois fines soit 77,78 %, suivi de la fibrose cicatricielle pulmonaire 55,56 % et la bronchiectasie de traction soit 44,44 %, l’emphysème para cicatriciel dans 22,22 %.Conclusion : Les sequelles radiologiques de la tuberculose thoracique au service de pneumo-phtisiologie de l’hôpital national Ignace Deen du CHU de Conakry intéressent un homme pour 1,45 femme avec une prédominance de la tranche d’âge 40-59. Le tiers des patients était tabagique et vivait avec le VIH. Le signe radiographique le plus retrouvé était une opacité rétractile avec destruction parenchymateuse. Le taux de réalisation de scanner thoracique était faible avec la cavité séquellaire comme principale lésion scannographique.
Objectives: to describe the sociodemographic profile of patients and the radiological sequelae of thoracic tuberculosis in adults.Materials and Methods: prospective and descriptive study of 12 months in 103 old tuberculosis patients received in consultation or hospitalization at the Pneumo Phtisiology service of the Ignace Deen National Hospital of the CHU of Conakry, treated and declared cured with radiological sequelae on standard radiography and / or chest CT. The study variables were socio-demographic (age, sex, level of education, occupation and smoking), biological (HIV serological status) and radiological (thoracic sequelae of tuberculosis). The data were collected on a survey form. pre-established and analyzed by epi info software version 3.5.3Results: The mean age of the patients was 46.83 years with extremes of 21 and 82 years. The most represented age group was 40 to 59 years old, or 48.5%. The history of pulmonary tuberculosis was found in all patients. The male sex was the most represented with 61 cases or 59.2% against 42 cases of female sex or 40.8%. Smoking was noted in 31.1% of the cases. And 28.2% of patients had a positive HIV serology. The retractile opacities with parenchymal destruction were the most frequent lesions on chest radiography 44.7%; followed by calcifications 34%, fibrous lesions 32%, bell images 31.1%. Pleural lesions were represented by pleural fornix fillings 21.36% and pleural calcifications 12.60%. The bone lesions by spondylodiscites 4.85%.Only 8.7% (9/103) of the patients were able to perform a chest CT scan, the most represented CT lesion was the thin-walled cavities, 77.78%, followed by pulmonary fibrosis 55.56% and DDB, i.e. 44.4%, para scarring emphysema in 22.2%.Conclusion: The radiological sequelae of thoracic tuberculosis in the pneumo-phthisiology service of the Ignace Deen National Hospital of the Conakry University Hospital concern one man for 1.45 women with a predominance of the age group 40-59. One third of the patients were smokers and were living with HIV. The most common radiographic sign was retractile opacity with parenchymal destruction. The rate of completion of a chest CT scan was low with the sequelae cavity as the main CT lesion
 
Usage des Rayonnements ionisants en milieu médical à Cotonou (Benin): Usage des Rayonnements ionisants en milieu médical à Cotonou (Benin)
No full textObjectif : Faire l’état des lieux des applications médicales des rayonnements ionisants dans la ville de Cotonou.Matériels et méthode : Etude prospective du 16 avril au 22 juin 2018 dans les structures sanitaires disposant de générateurs ou sources de rayonnements ionisants utilisés à des fins médicales dans la ville de Cotonou. Les paramètres étudiés étaient : les caractéristiques des structures sanitaires utilisant les rayonnements ionisants, les infrastructures techniques et ressources humaines impliquées, et la mise en oeuvre des mesures de radioprotection.Résultats : Les rayonnements ionisants étaient utilisés respectivement dans 22 services pour les rayons X, et 1 service pour les rayons gamma. Ces services ne couvraient que les 2/3 des arrondissements. Les générateurs de rayons X comprenaient les appareils de radiologie classique (52,1%), de mammographie (19,6%), de radiologie dentaire (15,2%) et de scanner (8,7%). Ces appareils étaient acquis à l’état neuf dans 52,1% et utilisés dans 63,1% dans les structures privées. Ils étaient dominés par les marques Siemens (20,8%), Schimadzu (12,5%) pour la radiologie classique. Les scanners avaient un âge compris entre 5 et 9 ans et étaient de 16 barrettes dans 50%. Quatorze radiologues et 65 manipulateurs étaient recensés. Près des 2/3 des manipulateurs avaient moins de dix années d’expérience. Aucune structure n’utilisait de dosimètre. Seulement 2 structures sanitaires disposaient de pictogramme et de règlement de zone. Un peu plus de 1500 patients étaient exposés aux rayons X par semaine et 150 dosages radio immunologiques étaient réalisés par semaine.Conclusion : L’usage des rayonnements ionisants était exclusivement à but diagnostique à Cotonou avec des mesures de radioprotection peu satisfaisantes.
Objective: Take stock of the medical applications of ionizing radiation in the city of Cotonou.Materials and method: Prospective study from April 16 to June 22, 2018 in health facilities with generators or sources of ionizing radiation used for medical purposes in the city of Cotonou. The parameters studied were: the characteristics of health structures using ionizing radiation, the technical infrastructure and human resources involved, and the implementation of radiation protection measures.Results: Ionizing radiation was used in 22 departments for X-rays, and 1 department for gamma rays, respectively. These services only covered 2/3 of the arrondissements. X-ray generators included conventional radiology (52.1%), mammography (19.6%), dental radiology (15.2%) and ct-scan (8.7%) devices. These devices were acquired in new condition in 52.1% and used in 63.1% in private structures. They were dominated by the Siemens (20.8%), Schimadzu (12.5%) brands for conventional radiology. The scanners were between 5 and 9 years old and were 16 bars in 50%. Fourteen radiologists and 65 manipulators were identified. Almost 2/3 of the manipulators had less than ten years of experience. No structure used a dosimeter. Only 2 health facilities had pictograms and zone regulations. Just over 1500 patients were exposed to X-rays per week and 150 radio immunoassays were performed per week.Conclusion: The use of ionizing radiation was exclusively for diagnostic purposes in Cotonou with unsatisfactory radiation protection measures