Chlorination has been the method of choice for disinfecting water used for drinking purposes. However, some stressed bacteria during chlorination are able to recover and alter the potability of water. This study assessed the recovery of stressed bacteria in dechlorinated water. Ten chlorinated water samples were collected from different points within Ilorin metropolis, Kwara, Nigeria. The samples (100ml) were dechlorinated with 0.1ml of 11.4mM sodium thiosulphate solution. The physicochemical characteristics of the chlorinated water samples were determined while bacteriological analyses were carried out on both chlorinated and dechlorinated water samples. The antibiotic susceptibility pattern of the isolates was determined using disc diffusion method. The physicochemical characteristics of the water samples ranged as follow: pH 7.3-8.4, chloride content 4.37-6.85 mg/l, suspended solids 0.004-0.017 g/100ml, and total hardness 30-72mg/l. The chlorinated water samples had bacterial, total, and faecal coliform counts ranging from 1.0 × 101 – 1.9 × 104cfu/ml, 0 – 480 MPN/100ml, and zero, respectively. The dechlorinated water sample had corresponding counts of 5.4 × 102 – 7.36 × 104cfu/ml, 6 - 1100 MPN/100ml, and 0 – 380 MPN/100ml. A total of eleven bacterial species belonging to the genera Bacillus, Burkholderia, Citrobacter, Enterobacter, Enterococcus, Escherichia, Staphylococcus, Serratia, and Streptococcus were isolated. Not lower than 60% of the bacterial isolates were susceptible to ofloxacin and ciprofloxacin. All the isolates exhibited multiple antibiotic resistances. The antibiotic resistance pattern of an isolate of Citrobacter freundii to cefuroxime, cefixime, and gentamycin changed remarkably and was plasmid-mediated, while that of E. coli and Enterobacter agglomerans remained unchanged to all the antibiotics and was non-plasmid mediated. Chlorination of water at the point of use is recommended. It is concluded that chlorination is essential in order to prevent reactivation of stressed bacteria during distribution and prevent infection by bacteria with high multiple antibiotic resistance index.
Nine new compounds of 2-amino-5-chlorobenzothiazole derivatives were synthesized. These new compounds were formed through the reaction of 2-amino-5-chlorobenzothiazole 1 with ethyl chloroacetate and KOH, which gave an ester derivative 2, followed by refluxing compound 2 with hydrazine hydrate to afford hydrazide derivative 3. The reaction of compound 3 with CS2 and KOH gave 1,3,4-oxadiazole-2-thiol derivative 4, and then the reaction of compound 2 with thiosemicarbazide to produce compound 5 then treated it with 4%NaOH led to ring closure to provide 1,2,4-triazole-3-thiol derivative
... Show MoreThe usual methods of distance determination in Astronomy parallax and Spectroscopic with Expansion Methods are seldom applicable to Nebulae. In this work determination of the distances to individual Nebulae are calculated and discussed. The distances of Nebulae to the Earth are calculated. The accuracy of the distance is tested by using Aladin sky Atlas, and comparing Nebulae properties were derived from these distance made with statistical distance determination. The results showed that angular Expansions may occur in a part of the nebulae that is moving at a velocity different than the observed velocity. Also the results of the comparison of our spectroscopic distances with the trig
Ten new thiourea derivatives 1-10 were prepared in this work using a two-step process that involved reacting 4-methoxybenzoyl chloride with KSCN to afford 4-methoxybenzoyl isothiocyanate. This was followed by reaction with various amines (primary amines, secondary amines, and diamines) to give the aforementioned title products 1-10. These products were characterized by FT-IR, 1H NMR and 13C NMR spectroscopy. Using the DPPH scavenging method, the antioxidant activity of thiourea products was investigated, and derivative 8 had the greatest antioxidant activity in comparison to the other derivatives. Moreover, molecular dockin
... Show MoreA modified Leslie-Gower predator-prey model with fear effect and nonlinear harvesting is developed and investigated in this study. The predator is supposed to feed on the prey using Holling type-II functional response. The goal is to see how fear of predation and presence of harvesting affect the model's dynamics. The system's positivity and boundlessness are demonstrated. All conceivable equilibria's existence and stability requirements are established. All sorts of local bifurcation occurrence conditions are presented. Extensive numerical simulations of the proposed model are shown in form of Phase portraits and direction fields. That is to guarantee the correctness of the theoretical results of the dynamic behavior of the system and t
... Show MoreAnxiety has become a highly paramount field of research attention in psychopharmacology today. Sundry studies have shown a nitric oxide role in the regulation of anxiety. The goal of the study was to investigate sodium nitroprusside ability to affect anxiety-like behavior in mice and to compare this effect with the standard anxiolytic drug, diazepam, using both plus maze test and light/dark box test. The results revealed that sodium nitroprusside at a dose of 1 mg/kg had a significant effect on the behavior in both of the elevated plus maze test and light/dark test. However, at higher dose (3 mg/kg), it has significantly increased the anxiogenic-like effect in the light/dark box test. Diazepam at a dose of 2 mg/kg increased the time spen
... Show MoreIn this paper, Zinc oxide were deposited on a glass substrate at room temperature (RT) and two annealing temperatures 350ºC and 500ºC using laser induced plasma technique. ZnO nanofilms of 200nm thickness have been deposited on glass substrate. X-RAY diffraction (XRD), atomic force microscopy and UV-visible spectrophotometer were used to analyze the results. XRD forms of ZnO nanostructure display hexagonal structure with three recognized peaks (100), (002), and (101) orientations at 500ºC annealing temperature. The optical properties of ZnO nanostructure were determined spectra. The energy gap was 3.1 eV at 300 oC and 3.25eV at 500ºC annealing temperature.