Quantitative Fluorescence Microscopy of Protein Dynamics in Living Cells

The advent of confocal microscopy, fast microcomputers with high storage capacity and, moreover, the availability of fluorescent proteins of various excitation and emission properties have made fluorescence microscopy the method of choice in the study of protein behaviour in living cells. In this thesis we investigated in detail two important quantitative methods, fluorescence correlation spectroscopy (FCS) and fluorescence recovery after photobleaching (FRAP). Model systems used in demonstrating the complementarity of the techniques and their merits included the nuclear excision repair (NER) system, transcription regulation by the androgen receptor (AR), and signal transduction by two membrane receptors, the EGF receptor and the IL2-receptor. In Chapter 1 an introduction to microscopy is given. A brief history traces the development of microscopy from the modest lens arrangement of Zacharias Janssen to modern fluorescence microscopes allowing quantitative investigation of protein dynamics in living cells. A discussion of fluorescence properties of the GFP is presented and several quantitative fluorescence microscopy techniques used are discussed. Also the model systems studied are described. In Chapter 2 the long-lived dark state of EGFP, the fluorescent tag used in most live cell studies, is investigated as observed in a set-up similar to a typical fluorescence recovery after photobleaching (FRAP) experiment. A method is presented to measure light in

Relationship of Soilborne Mycoflora of Cassava Growing Fields to Incidence of Postharvest Rots of Cassava Tubers in Sokoto, Nigeria

In this study the fungi associated with cassava growing fields in Sokoto were isolated and identified using soil dilution technique. A total of 215 fungal colonies from 9 fungal species were isolated from soil samples of different cassava fields between the month of June and August, 2012. It was observed that soil samples from Lambara recorded the highest number (64) of fungal species followed by Damba and the least number (44) of fungal species was observed in Wamakko.The fungi isolated were Alternaria species, Aspergillus Niger, Aspergillus fumigatus, Cylindrocarpon lichenicola, Fusarium oxysporum, Geotrichum candidum, Mucor hiemalis, Rhizopus orgyzae and Scopulariopsis candida.The highest percentage frequency of occurrence was observed in Aspergillus Niger (39.5%) seconded by Fusarium oxysporum (18.2%) and the least was seen in Rhizopus oryzae ( 2.3%). The pathogenicity test indicated that all the fungal isolates were pathogenic on cassava tubers.The fungus M. hiemalis is the most pathogenic followed by F. oxysporum and the least was recorded by R. oryzae. Therefore, it would be concluded that there is relationship between soilborne fungi and incidence of postharvest rots of cassava tubers

Evaluation of Physico-Chemical and Fungal Species Associated with Oil Contaminated Soil from Selected Automobile Garage in Sokoto Metropolis

This study was conducted with a view to evaluating the physicochemical and mycological properties of different oil contaminated soils collected from three different automobile garages in Sokoto Metropolis, and uncontaminated soil from the temporary site, Usmanu Danfodiyo University, Sokoto (UDUS) was used as the control. The pH was determined using pH meter model Hanna (H1991301), quantity of mineral elements was evaluated in accordance with Murphy and Fungi were isolated from the three oil contaminated samples (A, B. and C) and the uncontaminated (sample D) as control, this was done by standard procedure using the method of P. Ren, T. Jankun & B. Leaderer. The physical, chemical, and mineral elements from the oil-contaminated soils of the three automobile garages and control. The results of particle soil analysis revealed the high content of sandy soil (96.2 to 87.3) and silt is the lowest with (2.5–0.6). Magnesium had the highest concentration of studied minerals, ranging from 193 to 649.2 mg/kg. while PH result revealed that the soil samples were pH value ranged from (16.85–16.20) in oil Contaminated samples, while the control had 15.90, and electrical conductivity ranged from 12.8–13.8 % and 28 % in control, four fungal isolates Aspergillus sp., Penicillum sp., Mucor sp. and Sporobolomyces sp. were identified based on colonial, sexual and morphological characteristics. These fungal strains can be used in bioremediation process and oil pollution reduction in aquatic ecosystems

AN APPRAISAL OF THE TAX EVASION AND TAX AVOIDANCE SYSTEM IN INDONESIA

Tax avoidance and evasion are pervasive in all countries. This paper, firstreview a literature that integrate the tax avoidance and evasion into overall decisionproblem faced by government. The second, reviews the issue of corruption andbureaucracy, there is a link between tax evasion and corruption. This study uses literatureto analyze the cause and the effect of tax evasion and tax avoidance to environment.Finally, this paper will examine the effect of perceived corruption in government on taxevasion and how should the tax system in Indonesia face the tax evasion problem. Thegovernment attempts to improve the tax compliance in Indonesia with comprehensiveregulation of the schemes of tax avoidance schemes. Therefore, it need a specific antiavoidancerules in Indonesian tax lawDOI: 10.15408/akt.v8i2.288

Acute toxicity and anti-inflammatory activity of hydromethanol leaves extract of Allophylus africanus Beauv in rats

Introduction: The leaves of Allophylus africanus are traditionally used for the treatment of various ailments such as arthritis, rheumatism, gout, hemorrhoids, dysentery, venereal diseases and malnutrition. This study was carried out to evaluate the acute toxicity and antiinflammatory activity of the hydro-methanol leaves extract of A. africanus on laboratory rats. Methods:Allophylus africanus leaves were extracted with 80% methanol using cold maceration for 5 days. The extract was subjected to phytochemical analysis, acute toxicity study and antiinflammatory evaluation using carrageenan induced paw edema in laboratory rats. Results: The phytochemical screening of the aqueous methanol leaves extract revealed the presence of carbohydrates, tannins, steroids/triterpenes, flavonoids, alkaloids and cardiac glycosides. The extract was found to have median lethal dose (LD50) of 3807.89 mg/kg body weight orally and the aqueous methanol leaves extract at doses 250 and 1000 mg/kg produced significant anti-inflammatory effect at the 3rd, 4th and 5th hours with the effect being dose dependent at the 4th and 5th hours. There were remarkable reductions of paw edema in the rats. Conclusion: Allophylus africanus leaves has anti-inflammatory activity which explains the basis of its use in traditional medicine in the management of inflammation and related inflammatory disorder

Design, fabrication and testing of shea nut shelling machine

Sheanut (Butyrospernum paradoxum) is an oil rich tropical tree crop, which is indigenous to the West African savannah zone. In Nigeria, most of the sheanuts shelling are done manually by rural women and children, which is labour demanding and tedious. This research work was carried out to determine some physical and mechanical properties of sheanut in order to minimize economic losses associated with its processing. The mean values recorded for the physical properties at 25% moisture content (wb) are; major diameter (29.20 mm), intermediate diameter (21.90 mm), minor diameter (15.00 mm), geometric mean diameter (21.90 mm), arithmetic mean diameter (21.20 mm), angle of repose (30.280). The mean values for the mechanical properties are; linear limit force (0.80 kN), linear limit deformation (4.60 mm), bioyield point force (1.40 kN), bioyield point deformation (6.50 mm), rupture point force (2.10 kN) and rupture point deformation (9.60 mm). Based on the physical and mechanical properties, a sheanut shelling machine was developed that is capable of addressing the aforementioned problems. Putting into consideration better shelling and efficient separation of shea nuts so as to encourage more utilization and processing of shea nuts and its products. The machine was designed to be powered by 5 hp electric motor. It was tested to shell, separate and clean sheanuts. The result of the performance evaluation showed that the machine had shelling efficiency of 96%; cleaning efficiency of the machine was 69.56% while the recovery efficiency was 82.7%. The successful development of this machine will reduce drudgery and time taken associated with the traditional method of sheanut shelling and therefore will increase productivity and utilization

A Preliminary Study on Microbial Contamination of Leafy Vegetables in Sokoto Metropolis, Nigeria

Five leafy vegetables commonly consumed in Sokoto metropolis were evaluated for microbiological quality using standard procedures involving standard plate count (SPC). The vegetables investigated included Lactuaca sativa (Lettuce), Amaranthus hybridus (Spinach), Vernonia amagdalina (Bitter leaf), Brassica oleracea (Cabbage) and Moringa oleifera Lam (Horse radish). Ten fungal species which include Alternaria alternata, Absidia corymbifera, Aspergillus Niger, A. flavus, Cladosporium herbarum, Fusarium oxysporium, Geotrichum candidum, Mucor racemoses, Rhizopus stolonifer and Trichoderma harzianum and four species of bacteria: Bacillus cereus, Escherichia coli, Listeria monocystogens and Staphyllococus aureus were isolated from the leafy vegetables. The total colony counts of fungi ranged from 1.8 x 106 – 6.28 x 105 (cfu/g) of the vegetables while that of bacteria ranged from 1.0 x 106 to 2.94 x 106 cfu/g of the vegetables. The highest counts of microbial organisms were found on A. hybridus while M. oleifera and B. olerarea had the lowest fungal and bacterial counts respectively. There is a need to reduce the levels of microbial contamination on leafy vegetables through appropriate production practices, careful handling by the vendors and appropriate processing with a view to minimize the risk of human exposure to fungal and bacterial pathogens associated with the vegetables

A Study of Polysemy and Metaphor of Hausa Perception Verbs of Vision: A Cognitive Linguistics Approach

This paper examines the polysemy and metaphor of Hausa perception verbs of vision from a cognitive semantics perspective, which is a sub-field of cognitive linguistics. The objective of the study is to identify how underlying polysemous extensions of the Hausa perception verbs trigger the conceptual metaphor of vision. In conducting the research, ethnographic research methods were employed in collecting the data for this study, while the conceptual polysemy model proposed by Ibarretxe-Antunano (1999) and the conceptual metaphor theory (CMT) propounded by Lakoff and Jhonson (1980) were adopted as the theoretical framework of the research. The outcome of the study reveals that Hausa perception verbs of vision, when polysemously extended conceptually, encode an array of conceptual metaphors that conceptually denote mental activity and experience, social activity, and evidential experience. Finally, the result of the study establishes a relationship between perception and cognition. &nbsp

The effects of intrauterine ethanol exposure on the levels of Iron and Copper in Cerebrum and Cerebellum of neonatal Wistar rats

Neurodevelopmental disorders have been reported to be associated with infants exposed to ethanol in utero. The study was aimed at evaluating the effects of intrauterine ethanol exposure on neurobehaviour and the amount of iron and copper in the cerebrum and cerebellum of neonatal Wistar rats at different periods of development. Fourteen (14) female Wistar rats were mated with matured males in ratio 2:1 overnight following determination of oestrous phase. Pregnant dams were divided into 7 groups. Group A served as the control that received distilled water. Groups B, C and D were administered 0.5ml of 20% ethanol equivalent to 1st, 1st and 2nd trimesters and whole gestation period (i.e 1st, 2nd and 3rd trimesters) respectively. Groups E, F and G were given 0.5ml of 30% ethanol accordingly. Following parturition, neurobehavioural assessment on sensory and motor reflexes of the litters were tested on postnatal days 5, 6 and 7. Brain tissues were later excised, homogenised and analysed using Atomic Absorption Spectrophotometry. SPSS V20 was used to compare the mean difference using analysis of variance (ANOVA). The ethanol treated neonates in Groups B, E, F and G showed a statistically significant (p˂0.05) increase in latency to respond to sensory and motor reflexes when compared with Control Group. Interrelated elevation of both iron and copper was observed in the cerebellum while both the amounts of iron and copper in the cerebrum were depleted. It is concluded that intrauterine ethanol exposure has effect on the development of vestibular, postural, sensory and motor coordination. The alterations in the amounts of iron and copper which are important cofactors for certain neurotransmitters and enzymes in the brain could play role in the neurobehavioural deficits observed. Intrauterine ethanol ingestion affects development of sensory and motor reflexes as well as the amounts of iron and copper in both cerebrum and cerebellum in a reciprocal manner. Keywords: ethanol, intrauterine, neurobehaviour, neurochemistr