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Hazard Assessment of Some Heavy Metals in Tema Municipal Water Supply
Nakotey, Ebenezer
The study was undertaken to assess the quality status of drinking water in Tema municipal area. The concentrations of some selected toxic heavy metals (copper, zinc, nickel, cadmium, mercury, chromium, lead, iron, and manganese) were determined using Atomic Absorption Spectrophotometer. Among the nine selected heavy metals nickel and lead show higher concentration than the WHO recommended limits. This is an indication of pollution however their hazard quotients (HQ) of 0.04875 and 0.034938 is far less than 1. Besides, hazard index and incremental lifetime risk were calculated to be 0.0866 and 4.499 x 109 respectively. Since hazard quotient is far less than 1, and the risk value of 4.499 x 10-9 is also far less than 1 x 10-6 it implies no health risk is associated with the water and therefore their presence had no significant health effect on human life.
Studies on the effects of the antimalarial drugs, chloroquine sulphate on phosphorus metabolism in rats
(1970) Abotsi, Emil Komla
Chloroquine sulphate (NIVAQUINB) is a member of 4-aminoquinolines used for treating acute malaria: due to infoctions "by Plasmodium vivax. Plasmodium falciparum. Plasmodium malariae and Plasmodium ovale. The offect of chloroquine sulphate on phosphorus uptake and. its metabolism in the red blood cells and the liver of rats has been studied by radioisotopic and non-radioisotopic techniques in an attempt to find whether the drug has any influence on the phosphorus metabolism in these tissues. Tho radioisotopic studies involved the treatment of albino rats with 100 ng/kg of chloroquine sulphate for 6, 12 and 24 hours. The blood samples were incubated with 32p_orthophosphate in Krobs Ringer solution, pH 7.4 and activities were determined by Geigor-Muller end window type counter. The activities were compared with control animals. There was no effect of the drug on the uptake of phosphorus by the red blood cells. Studies were also made on the acute toxicity effects of the drug on phosphorus metabolism in the rod blood cells and the liver. The various phosphorus fractions if ore measured spec tro photometrically by the technique of Baginski et al (9). After administration of 100 mg/kg for 12 hours and 24 hours, there was no significant effect of the drug on phosphorus metabolism in the red blood cells. Studies were also made/on the response of the different sexes to chloroquine sulphate. By comparing the results of the .males With those of the females, it has been submitted that administration of chloroquine sulphate might increase the synthesis of organic phosphates in the rod blood cells of males and also in the plasma of females. However, in chronic toxicity studies, daily administration of small doses of 5 mg/kg of chloroquine sulphate for 8 weeks resulted Ih increases of 35% and 27% in inorganic phosphate and total acid hydrolysable phosphates respectively in the red blood cells, whilst a decrease of about 16$ was noticed in the total phosphate of the plasma. An increase was also observed in the labile phosphate fraction. A long period of administration of the same dose for 16 weeks showed decreases in the bound and total phosphate fractions. Acute toxicity studies in the liver by non-radioisotopic technique revealed increases in the total and bound phosphates. These increases were found to be due to an increase of 20% in the phospholipids. These findings suggest that there might be increased synthesis of phospholipids. Chronic toxicity studies showed no significant effects after daily doses of 5 mg/kg for 8 weeks, whilst increases of about 12% and 11% were noticed respectively in the inorganic and total acid soluble phosphates after 16 weeks of administration of fee same dose, It has been suggested that longer periods of administration of chloroquine sulphate might increase in the liver, the formation of enzyme systems that metabolise the drug administered into a more active form. Finally studies on the effect of chloroquine sulphate on the activity of acid phosphatase in the red blood cells and the plasma by the method of king et al showed that the enzyme was not affected during acute toxicity studies.
Automation of the acquisition and circulation systems of the U.S.T. Library
(1979) Osei-Agyemang, Kwaku
1.1 Introduction: Information is the essential ingredient in decision making. The need for improved information systems in recent years has been made critical by the steady growth in size and complexity of organisations and data. The time has come when librarians are forced to turn to computers in order to give satisfactory service to their patrons. It is the objective of this project to suggest to the library administration and personnel of this University how automation can improve the Library services and how to make the change from normal to automated systems. No claims are made that an automated system is not as costly as a normal system. I feel, however, that computers make possible better utilization of personnel and under more flexible range of services. The project discusses those of Library activities that ca successfully be automated, the major design considerations, methods of implementing the systems and methods of converting from a manual to an automated system. 1.2 Why this Project? U.S.T. Library is one of the largest libraries in the country. The rate of growth of the community that this Library is supposed to serve makes it imperative fro certain operations to be automated so that information rational which is the basis of the ordering sub-system, the circulation sub-system could be faster. Information as to availability of the circulation or the order of a particular book should be made readily available to who ever needs it. It is my fervent hope that this project will come up with something interesting and useful to the Library personnel and thereby help to improve some of the operations in the library. Since the need fro automation has already well received by the Librarian, the major problem which is the human behaviour towards any proposal for a change has been eliminated. The staff who will be involved in the various operations have also responded favourably to assurances that the computer is not going to displace them to perform those tasks which they have been performing daily much faster. The term Library Automation refers to the processing of certain routine clerical functions in the library with the assistance of computers or other mechanized or semi-automatic equipment. This Automation will release the Library staff from many routines, administrative or clerical functions. Thus it will not replace the Librarian or make for the Librarian any decision involving professional judgement. A conspicuous example is in the assignment of the subject headings. Obviously these must be assigned by a trained cataloguist. There are three main areas main of Library operations – Administration, Management and Library science. The benefits which the Library will derive from this proposed automated system will be as follows: a) Clerical Function The amount of routine clerical work will be significantly reduced. The reduction in positions will be offset to some extent by corresponding increases in Computer costs. The professional Librarians by releasing these tasks to a computer will be left with more time to spend on questions that are more in the Library’s interest. b) Processing Speed The use of automated methods will invariably speed up the flow of work in the Library. New books, reports and other material will therefore be released sooner to waiting reader. c) Work Control Work-load, personnel and transaction statistics and records will be automatically prepared. Because of the availability of improved statistics, improved cost control and improved planning will be possible. d) Protection of Records Because of the ease and economy of producing and distributing multiple copies of catalogue files, the automated systems will provide greater protection against loss of the catalogue by fire, or any natural disasters. e) Financial The automated system will be properly planned so that unit operating cost will be drastically reduced. Expenditures which will be saved from Clerical effort will be transformed to book purchases or to provide New Service to users. f) Increasing Work Load The automation system will remove all the difficulties and caused by several factors which have combined to cause permanent increase in the Library work loads. These complexities have made information retrieval increasingly difficult and will be removed by the automation system. g) Staffing It will be preferable to meet the needs for increase the use of equipment rather than increasing the number of personnel employed. Generally equipment is cheaper than personnel. It is more reliable (in the sense of breakdowns, vacations etc) more flexible and does not become bored. As the computers will never be on vacation or sicks leave and will rarely need pairs they will be more dependable and will work longer hours than people. h) Exception Reporting The Automated system will automatically provide overdue notices follow up notices, location of orders, editing of cataloguing activity. i) Accuracy The automation system will significantly increase the accuracy of files and records. Processing rules will be standardized and given to the computer in the form of a program which can be used to verify that rules for the new data are being followed. The Input will be edited by the Computer and the errors which will be detected will be corrected before the information will be entered into the files and processed. Once correctly entered into the computer file, the information will always be printed or sorted consistently and correctly thereafter. j) Distribution Information to Other Libraries With automated system catalogue information from the Central Library holdings will easily be distributed among the Faculty Libraries.
The role of micro-organisms and endogenous pectolytic enzymes in the fementation of cocoa
(1983) Ansah, Florence
The cause of sweating of cocoa and the involvement of micro-organisms in the process were investigated. The roles of microbial and non-microbial pectolytic enzymes in the fermentation of cocoa pulp were studied by means of aseptic micro-fermentation methods. Fermentations were carried out on a laboratory scale under sterile and non-sterile (natural) conditions and the sweating rates and yields monitored over the first 12 hr of fermentation. The beans were subsequently assessed for quality after 6 days of fermentation, and drying. Sweating obtained under sterile conditions was attributed to endogenous enzymes. Increased yield and rate of sweating observed under natural conditions, however, suggested that microorganisms played a significant role in the process. In a 12-hr collection under natural conditions, there were increases in yield of the order of 130% over sweating yield under sterile conditions. Enzymological studies under both sterile and natural conditions revealed the presence of two types of pectolytic enrynes in pulp. Pectin Esterase, (P.E.) and Polygalacturonase (P.G.) activities were detected in pulp. Inhibition of P. B. produced a 31.7% reduction in yield of sweatings, suggesting a partial involvement of the enzyme in the process. Changes in viscosity of sweatings, as well as histological Studies of the enzyme’s action on pulp indicated that P.G. is the cause for sweating. Further indications of this were obtained when the addition of different concentrations of “Commercial P.G.” to fermenting cocoa beans produced large increases in sweating rate and yield. Increases in drainage of over 200% adversely affected the quality of the bean, whilst below 150%, they were acceptable. Of several microorganisms isolated from fermenting cocoa beans, A. niger and a Penicillium sp. were found to be strongly peotolytic. When applied to cocoa beans, they produced increases in yield of about 190% and 170% respectively. Two other fungi obtained from the American type Culture Collection produced significant increases in sweating rate and yield when applied to cocoa beans. A. oryzae produced about 60%, G. candidium approximately, 35% increases in yield. Thus, depending on the choice of organism, pectolytic fungi can be employed as starter cultures in the fermentation of cocoa, to give optimum yields of sweatings within the first 12 hours of fermentation.
Insect infestation and quality deterioration of some animal feedstuffs in storage
(1983) Owusu-Akyaw, Michael
The susceptibilities of white maize and yellow maize to Sitophilus zeamais (Motsch); of rice bran, maize bran wheat bran and brewer’s dried grain to Tribolium castaneum (Herbst); of soyabean meal, copra meal and groundnut meal to Ephestia cautella (Walk.), were tested. Yellow maize was significantly more susceptible (p < 0.01) to S. zeamais than white maize. Wheat bran, maize bran and rice bran did not significantly differ (P < 0.05) in susceptibility to T. castaneum whilst brewer’s dried grain was significantly less susceptible (P<0.01) to the insect than any of the others. The susceptibility of the oilseed meals to E. cautella was in the order: soyabean meal>copra meal> groundnut meal (p<0.01). Changes in insect population and in quality of infested and un- infested feedstuffs stored for one, three, six and nine months under laboratory conditions were studied using the test feedstuffs and insects above and then fish meal infested with Dermestes maculatus (Degeer). Throughout the test period, no significant increase was observed in the number of insects originally introduced into brewer’s dried grain and. groundnut meal and also no adults emerged from the pupae produced in fish meal. Mite contamination 4as observed in only the infested yellow maize and white maize and the infested and uninfested fish meal. Hea.ing occurred in only the infested yellow maize and white maize from the third to the ninth month and the infested and uninfested fish meal in the first month. Changes in colour and odour were noted in only the samples and extracted oil of the infested yellow maize and white maize and the infested and uninfested fish meal from the third to the ninth month. Apart from the moisture content of the uninfested copra meal which reduced and that of all the samples of brewer’s dried grain which remained unchanged in storage, the moisture content of the infested and uninfected samplen of all the feedstuffs increased with times. Of the percent proximate nutrient contents, only the crude fibre content of all the test samples, the crude protein content of the infested and uninfested rice bran, maize bran, brewer’s dried grain and wheat bran and the uninfested yellow maize and white maize, and the ash content of all the test samples but fish meal did not significantly change in storage.
Evaluation of Volta resettlement scheme: (A Comparative study of Akosombo and Kpong resettlement scheme)
(1984) Oppong-Nkrumah, Kofi
Ghana has undertaken many resettlement schemes as a result of development projects; for example Weija, Asuofuah, Tema Manhean, Akosombo and Kpong resettlement schemes. The Akosombo resettlement was built in 1962 by the VRA as a result of the Akosombo dam which displaced about 80,000 people living along the river. The objective of the resettlement was to enhance the social, economic and physical conditions of the people by providing the people with improved housing condition and improved agricultural system. The government took the resettlement scheme as an opportunity to train people in new techniques of farming and other jobs to enable them contribute to the development of the nation as a whole. Unfortunately, the exercise was not successful as expected. Lack of time, finance, personnel and equipment affected the whole programme. Social and physical infrastructure could not be provided and the agricultural programme could not take off. Many settlers left the townships end lived somewhere. The same VRA had the opportunity to build the Kpong dam and to resettle the displaced people. It was therefore expected that the authorities would learn from their mistakes in the Akosombo scheme and take measures to make the settlers contribute to development. The objective of the study was to compare the Akosombo and Kpong resettlement schemes, find out the extent of the improvements in the pong scheme and to make suggestions to how best future resettlements can be undertaken and propose solutions to the problems identified in the Kpong resettlement scheme. The study limits itself to AKosombo and Kpong resettlement schemes. Information on Akosombo was basically from documentary sources while information on Kpong was both documentary sources and field surveys. From the study it was found t hat there was a marked improvement in the Kpong resettlement scheme as a whole. There were enough services and facilities and some attempt made at providing land for farming. Recommendation are made as a guide for future resettlement schemes and specifically for solving the problems identified in the Kpong resettlement scheme. some of the recommendations are that resettlement programmes should be gradual and should take place before the dam construction to enable the evacuees to undertake farming and other activities at the new sites, There should be little interference in the lifestyles of the people in order not to ma them feel alienated at the new site. Houses should be in the local materials so that the people can build upon that and services should be provided even if they were not found in the old communities. Enough land should be provided for the people to continue their farming activities agricultural facilities and services should also be provided.
Studies of some strains of Rhizobium Sp. on some tropical legumes
(1984.) Abaidoo, Robert Clement
Rhizobiun isolation were obtained from root nodules of Vigna unguiculata, Vigna radiate var aureus, Vigna subterranee, Fueraria sp. and Centrosema sp. and were designated as CP, GG, BB, PR and CT respectively. They were tested in the laboratory initially to comfirm their source and identity. Their cultural differences were established on yeast-water mannitel agar and other solid media. Also their susceptibilities to a set of antibioties were determined and used to differentiate between the isolates. The isolates were further tested for their levels of utilization of various carbohydrate substrates and the information obtained used to provide substitutes for mannitel – a common carbohydrate for rhizobia isolations and differentiation. The cross-inoculation concept has received much criticism in recent years. This was validated with the cross-infectivity and nodulation tests. This was done by inoculating a legume seedling with all the Rhizobium isolates from the other legume to look for nodulation Successful isolates on Vigna radiate var aureus and Vigna subterranea were further studied in the soil and their nodulation was observed to supply information on the following: (a) Pattern of nodulation; (b) Nodule surface characteristics; (c) Nodule sizes; (d) Nodule numbers ; and (e) Nodule dry weights. The nodules were further observed for their ability to fix nitrogen in the soil and the distribution of the fixed nitrogen to the plant part viz nodules, roots and shoots. In addition, nitrogen fixed in the soil was also evaluated to relate to the potentialities of the symbiotic system to either increase plant protein or soil nitrogen. The observations made were considered on the basis of the individual isolates and comparisons were made with each other and also with the untreated controls where applicable. The reactions of the isolates to the various laboratory tests, especially the cultural differences and susceptibilities to the set of antibiotics put the five isolates into two groups – isolates CT and CP in one group while isolates PR, BB, and GG were put to another group. Carbohydrate utilization confirms mannitel as the beat metabolized carbohydrate and also provided other useful substitutes such as inositol, galactose and glucose. An attempt to use differences in levels of carbohydrate utilization to separate the isolates, however, did not yield good results. The result of the cross-infectivity tests confirmed the claims by earlier workers to reject the concept of cross-inoculation groups, and especially the cowpea cross-inoculation group, as a mechanism of differentiating between Rhizobium strains. The concept could not hold true for the three botanical species. i. e. Vigna unguiculata, Vigna subterranea and Vigna radiate var aureus. Information supplied by the nodulation studies brought out the fact that host plants reacted differently to the isolates and this was clearly shown by the different nodule surface appearance and to some extent the number of nodules produced. On Vigna radiate var aureus, nodule surface characteristics produced by isolates PR and GG were closer to each other than they were to isolate CT which confirms the existence of subgroups within the group of the isolates used as already established in some laboratory tests. Differences between isolates on nodule number, size and dry weight were, however not significant at P = 0.05 thus maintaining the three isolates CT, PR, and GG in the same cross—inoculation group. Observed differences in the total nitrogen fixed by the different symbiotic system were not large enough to establish distinct specification among each set of isolates on the legumes used. These non-significant differences were also obtained for the inoculated and the uninoculated plants. From this, it could be assumed that the initial nitrogen content of the soil sample might have not permitted the expression of the full potentialities of the isolates in nitrogen fixation, thus providing and equally good growth medium for the uninoculated control plants.
Development of multiplication medium for Bacillus thuringiensis H-14 using groundnut meal
(1986) Edoh, Dominic Adotei
Bacillus thuringiensis H-14 strain IPS-18 obtain from W.H.O. was microscopically studied to confirm its identity. Local groundnut seeds were defatted using mechanized, solvent, water and roasting methods. The press cakes obtained were chemically analysed and formulate into maintenance solid media. Growth rates of the bacterium on a number of pressed cake media composed differently were compared with those on standard nutrient agar medium. A formulated medium containing groundnut cake obtained from local edible oil factory and enriched with 0.25% glutamic acid was found to be very suitable for the propagation of the bacterium. The maintenance medium of the new formulation yielded better results than the standard agar medium by 1.2 times. The comparative mass production studies of the bacterium in the proposed medium and in the standard nutrient broth medium were carried out 500 ml Erlenmeyer shaker-flasks. The bacterial growth in the new medium at 24 and 48 hours was 2.6 and 1.3 times respectively greater than that in the standard nutrient broth medium. The total cell count of the bacterium in the new medium and the standard medium at 48 hours were 4.00 x 1021 cell/ml and 6.00 x 1017 cell/ml respectively. The total cell count and LC50 value of the bacterium on Aedes aegypti larvae in the new medium at 24 hours were 7.41 x 1013 cells/ml and 10-5 dilution respectively whereas those in nutrient broth were 8.60 x 107 cells/ml and 10-3.5 dilution respectively. The potency of the formulation was found to be 32,707 ITU/mg as compared with 4,000 ITU/mg for the standard medium. The cost of one litre of the maintenance and cultivation from the now medium were $0.18 (¢16.09) and $0.04 (¢3.45) respectively as compared to $1.45 (¢131.00) and $0.51 (¢45.00) respectively for the standard medium as at June 30, 1986
Propagation of Bacillus thuringiensis israelensis on cowpea vigna unguiculata.
(1986) Amisah, Stephen
The possibility of using Cowpea seeds as protein base for the cultivation of Bacillus thuring israelensis is investigated. Cowpeas contain carbohydrates, proteins and mineral, nutrients needed for the growth and sporulation of the bacillus. Baciillus thuringiensis isaelensis on Nutrient broth and Cowpeas formulations supplemented with various concentrations of monosodium glutamate. Monosodium glutamate at a concentration of 0.4% gave the beet growth of the organism on Cowpea medium whilst a 5% concentration gave the poorest growth. Dilutions of the Bacillus in Cowpea medium and in Nutrient broth ranging between 10-7 and 10-7 caused deaths in fourth instar larvae of Aedes aegypti. The L.C50 for the organism fermented in Monosodium glutamate in Cowpea medium was 10-4.5 whilst that of Nutrient broth was 10-4.0. Monosodium glutamate in Cowpea medium warn found to be a more efficacious and less costly medium for the propagation of the Bacillus as a microbial insecticide. Monosodium glutamate in Cowpea medium formulated as 0.4% Monosodium glutamate in 99.6% Cowpea extract barn bean recommended as an alternative medium to the rather costly nutrient broth as a protein base for the propagation of Bacillus thuringiensis israelensis as a microbial insecticide.
Production of Some Organic Solvent using Microorganisms
(1987) Muwuli Awuza, Johannes Akpabla
Cassava and sweet potato pulps and starches have been show to contain the following sugar: hydrolysed and unhydrolysed cassava pulp and starch – maltose and glucose; hydrolysed and unhydrolysed sweet potato pulp – maltose, glucose, sucrose, fructose and rharnose; hydrolysed sweet potato starch – maltose and glucose. An unidentified sugar was suspected to be present in both the cassava and sweet potato pulps. A strain of Saccharomyces cerevisiae has been isolated from palm wine. The alcohol tolerance of this strain was quite high – 9.3 (v/v). It fermented blackstrap molasses more efficiently than Baker’s Yeast. It also ferments hydrolysed cassava and sweet potato pulp and starches quite efficiently. The major fermentation product in each case was found to be ethanol
Beneficiation, Analysis and Industrial Utilization of Kaolin from Ghana
(1987-06-07) Harry, Vincent Kodzo
Eight different Kaolin samples were studied. Each sample was given serial number for easy reference. The beneficiation methods used in the project included a preliminary treatment of each sample; this involved hand 1cking of coarse gangue such as root, pebbles and coarse mica. After this treatment, each sample was subjected to gravity separation. Other beneficiation methods used included screening of samples at 120 mesh size and froth flotation using a flotation cell. After beneficiation, sodium dithionite, ammonium oxalate and oxalic acid were tested as bleaching agents and sodium dithionite was found to be the most suitable. Qualitative and quantitative analyses were carried out on the samples. Besides, moisture content and ignition loss were determined for each sample. Concentrations of Al2O3, SiD2, TiO2, Fe2O3, Na2O, K2O, CaO and MgO in the samples were determined by calorimetric and flame photometric techniques. Finally, physical properties involving oil adsorption, specific gravity, texture, finess and colour were determined for each sample. After gravity separation, the weights of recovered samples range from 31.52 to 81.48g out of 100.0g of raw samples used. Weight of samples recovered after screening 30.0g of each sample range between 16.59 to 28.23g. For froth flotation, weight of samples recovered after using 50.0g of each sample range between 47.42 to 49.88g. Results for moisture contest of samples range between 0.24 to 1.76% while ignition loss range between 7.79 to 31.67%. This thesis is divided into five chapters. Chapter or is a general introduction which deals with the origin of Kaolin and bow the deposits are formed. The uses of the clay have also been outlined aention4n the products which are made up of or contain Kaolin in diverse forms. The prominent deposits of the clay in Ghana have been mentioned here. In addition, the present status of kaolin utilization Ghanaian industries has been considered using GIHOC paints Company, Tema as a case study. Chapter two is on literature survey. In this chapter there has been a careful review of the way Kaolin deposits are formed. The chapter also contains to a great detail how different kaolin minerals are identified. Kaolin as a mineral possesses both physical and chemical properties. This chapter contains facts about these properties and their effects on the use to which kaolin can be put. Mining and beneficiation methods were also considered here with brief outlines on specific methods employed by some Companies in mining and beneficiating of kaolin. Finally a detailed outline on the technologies of some of the industrial utilizations of kaolin has been mentioned her. Chapter three has been devoted to experimental methods and their theories. This chapter has been divided into two broad sections. The first section is devoted to the chemistry of the analytical methods and the principles of the various instruments used in the experimental procedures. The second section is on the experimental procedures adopted in the study. Chapter four is on the results of the experiments performed. Chapter five has been devoted to discussion of results. Under it, the various methods of beneficiation used in the project have been discussed. A proposed pilot scale production scheme based on these methods of beneficiation has been put forward. The chapter also contains discussion of the results obtained from the analyses of the beneficiated products. Results were compared with those of well-known Commercial Kaolin samples and found to be in close conformity. Where deV1atioma were too much, possible reasons were put forward to explain the situation. The properties the kaolin samples were also compared with those of standard samples and aged upon these, the various Industrial uses for which the individual kaolin samples could be suitable were discussed in the chapter. The final thing considered in the chapter has been a survey work on the trend of worldwide and Ghana demand of kaolin. Despite the fact that me adequate data were available for a more comprehensive analysis on the economics of the present and future demands of kaolin in Ghana, an attempt has been made in this chapter to however give a rough idea about the present and future prospects of kaolin production in Ghanaian industrial scale.
Synthesis and characterization of N-acylsubstituted amide and thioamide complexes of some divalent transition metal sulphates
(1988-10-21) Adei, Evans
Acyclic N-acylsubstituted amides, RCONHCOR(I,R=R=Ph, II,R=Ph,R=Me) and thioamides, RCSNHCOR (III,R=R=Ph;IV,R=Me,R=Ph) were prepared. The N-Benzoylthiobenzamide(III) was synthesized as a new compound and characterized. These ligands were then employed in synthesizing complexes with some first row divalent transition metal sulphates (M(II)=Mn(II), Fe(II)Co(II), Ni(I), Cu(II) and Zn(II)) for the first time using solid-solid interaction. The decomposition temperatures, the temperature dependence of the solubilities and heats of solution in some organic solvents, of these imides and thioimides reported, give an indication of a stronger hydrogenbonding association in RCONHCOR (NH…O=C) than in RCSNHCOR (N-H…S=C). The infra-red spectra of these imide and thioimide complexes reveal that RCONHCOR co-ordinates to M(II) through the oxygen atoms the imide group (-CO-NH-CO-) in trans-trans configuration whilst M(II) complexes of RCSNHCOR involve co-ordination through the oxygen and sulphur atoms, of the thio-imide group (-CO-NH-CS-) also in the trans-trans disposition. The replacement of the methyl group in N-Benzoylacetamide with a phenyl group shifts the Imide Ia and Ib bands to lower frequencies, whereas a shift to higher frequencies is observed for the corresponding Imide Ia and Ib bands in going from N-Acetylthiobenzamide to N-Benzoylthiobenzamide. Consequently the Metal ligand bands in N-Acetylthiobenzamide are stronger than the corresponding bands in N-Benzoylthiobenzamide. A similar trend is observed in the case of N-Benzoylacetamide series on one hand, and N-Benzoylbenzamide on the other. The electronic spectral data, supported by magnetic susceptibility data, suggest an octahedral environment for Mn(II), Fe(II), Co(II), Ni(II) and Zn(II) complexes whilst the Cu(II) complexes exhibit square planar configuration.
Starter culture for corn grist fermentation
(1989) Obiri-Danso, Kwasi
Microorganisms involved in the Fermentation of corn dough were isolated frog local products using serial dilution and pour plate techniques. The morphological and biochemical characteristics of the Isolates were studied in pure cultures. The dough microflora comprised Saccharomyces cerevisiae, Candida tropicalis, Candida kefyr and Candida krusei. These isolates were tested for their ability to utilize soluble carbohydrates as carbon sources of energy for growth. The isolates as well as combinations of them were inoculated into fresh corn grists at a seeding rate of 1 x 106 cells per ml Fermentation was monitored for 96 hours for the following parameters: per cent moisture, total nitrogen, total acidity, solubility, total sugars and dough rise. Also pH, viable yeast count, temperature, aroma, taste and texture were determined daily each for 4 days. Glucose, sucrose and galactose gave the Seat growth for Succharomyces cerevisiae, Candida tropicalis and Candida kefyr whilst Candida krusei multiplication was supported by only glucose. Temperature increased from 25oC to 29oC within the initial 24 hours and remained constant; moisture per cent increased progressively throughout the fermentation period. pH decreased significantly ( 0.05) from pH 6.55 to pH 3.70 4.00 at the end of 96 hours. Also acidity per cent increased significantly (P 0.05) from 0.11 to 0.39-0.54 (in terms of lactic acid) with fluctuations due to ester formation. Percentage sugars decreased significantly (P 0.05) from 5.10-5.00 to 1.10-0.70. Viable yeast numbers increased at a rate of 10 - 60 per cent every 2 hours during the first 48 hours but decreased by 13 - 62 per cent within the next 48 hours. Digestibi1ity improved by 41 per cent. Also observed was per cent total nitrogen which increased by 4 – 14 per cent at the end of 96 hours. Volume of corn dough increased by 10 -33 per cent during the first 24 hours but later fall to 9 – 25 per cent. Sactharomyces cervisiae, candida tropicalic and Candida kefyr produced the best acceptable flavours. For starter culture production to be used for controlled fermentation, the three yeasts can be recommended.
The effect of plasma prolactin and milk lactose levels on the lactation performance of Ghanaian mothers and on the weight gain of their babies
(1989) Aboagye, Philip Kwame
The epidemiological Surveys done in Accra, Sunyani and Kumasi gave 21%, 27% and 28% respectively as the proportion of mothers affected by poor lactation performance or lactation problems. Graphical analysis and tests performed on the data of anthropometric measurements showed that babies from mothers without lactation problems generally weighed more than babies from mothers with lactation problems even though they were on supplements. This Suggests that mother’s milk could be a better promoter of infant growth than infant formulae. Prolactin was determined by immunoradiometric assay and lactose by the method of Asatoor and King. Analysis of the data on prolactin, lactose and infant weight in relation to lactation performance by the T test showed an association between lactation performance and plasma prolactin only in the 8 - 12 week period when the mother’s nutritional status had declined. It was observed from the survey that the peak of poor lactation performance occurred in the 8 - 12 week period. T tests on the relationship between lactation performance and the weight of babies during this period showed a close association in which case babies from mothers without poor lactation performance weighed more than the babies from mothers with lactation problems. Prom these observations it is possible that the first 8 - 12 weeks is a critical period of the babies’ life and in the lactation performances of the lactating mothers studied.
Screening for candidate Bacillus Spp. for the control of cultcine larvae
(1990) Amankwah, Mark Kofi
Mosquito breeding sources in and around U.S.T. campus as well other areas in Kai were identified, in addition, suitable breeding resources were set up around the Department of Biological Sciences. Blackfly breeding sites along tan (10) rivers in two onch- cerciasis-endemic areas, at Kintampo and Dunkwa-On-Offin districts, as veil as two rivers around U.S.T. campus, a non-disease-endemic area, were also identified. These sources were screened regularly for moribund and dead mosquito and blackfly larvae. The insects were processed for the isolation of Bacillus spp. Five Bacilius spp. were isolated trial pathogenicity tests of the isolates were performed on fourth instar larvae of Andes aegypti and culex quinquefasciatus. Only one of the isolates showed significant pathogenicicy towards C, quinquefasciatus larvae. This isolate was selected and its larvicidal activity was evaluated through bioasaays. The isolate was multiplied by allowing it to undergo fermentation in nutrient broth under continuous aeration by shaking using a flask shaker. The rate of increase in viable cells and spores as veil as changes in the 1vels of protein, optical density and pH were determined, at specific time intervals, during the course of fermentation, The activity level of the isolate, in terms of the LC50, was estimated to be 3.95 x 103 cfu/ml against C. quinquefaeciatus. Against A. aegypti however, the activity level was found to be extremely by, with LC50 of 4.30 x 106 cfu/ml. Based on microscopic studies, cultural, physiological or biochemical tests, the isolate was identified as a strain of Bacillus sphaericus that produced rather large parasporal inclusion bodies. When phage—typed, isolate did not pod in the same way as any of the know strains of the bacterium. This strain appeared to be a bacteriohpage group 4 strains.
A study of the factors influencing the reproductive performance of female N’Dama And Fresian X N’Dama cattle in the hot humid forest zone of Ghana.
(1990) Karikari, Paul Kofi
The reproductive records of N’Dama and Fresian X N’Dama cattle at UST Dairy/Beef Cattle Research Station were analysed and the progesterone-radioimmunoassay technique used to investigate the determinants of reproductive performance. Mean birth weights were 17.2 ± 5.1 and 28.32 ± 6.7kg for the N’Dama and Fresian X N’Dama cattle respectively. Bull calves of the Fresian X N’Dama weighed significantly heavier (P < 0.05) than the heifer calves at birth. The mean birth weight of the Fresian X N’Dama calves born in the wet season was also significantly higher (P < 0.05) in the dry season. Puberty was reached at mean ages of 684.33 ± 133.8 and 626.33 ± 188.96 days for the N’Dama and Fresian X N’Dama heifers respectively. Endocrine function at puberty was, however, abnormal and pubertal heifers had to wait a mean of 69 days before fertile oestrus. Minimum weights of 510 and 180 kg were required for the initiation of sexual cyclicity in the N’Dama and fresian X N’Dama respectively. The mean ages at first calving were 1045.93 ± 148.9 and 990.0 ± 161.4 days for the N’Dama and Fresian X N’Dama respectively, while the respective calving intervals were 511.6 ± 166.6 and 368.0 ± 162.8 days. Calving intervals was significantly longer (P < 0.05) for the N’Dama which calved in the wet season than for those which calved in the dry season (558.78 ± 187.1 vs 447.76 ± 177.2 days respectively) Ovarian luteal inactivity lasted a mean of 180.96 ± 135.9 days for the N’Dama and 82.69 ± 54.6 days for the Fresian X N’Dama. The interval from calving to ovarian luteal activity was, however, significantly lower (P < 0.05) in the N’Dama cows which nursed their calves only up to 3 months compared to those which nursed beyond 3 months (85.0 ± 48.8 vs 256.36 ± 135.5 days respectively). Mortalities were 20 and 19 percent for the N’Dama and Fresian X N’Dama respectively. Ninety two percent of the N’Dama deaths occurred in calves up to 6 months of age while only 42 per cent of the Fresian X N’Dama deaths occurred in animals of comparable age. Undernutrition and enteritis in calves accounted for 55 percent of the deaths in the N’Dama, but the heartwater disease was more important in the Fresian X N’Dama, accounting for 50 per cent of the deaths. Age at puberty, season of calving, postpartum anoestrus and culling were found to be important determinants of reproductive performance. The results suggested that early weaning (with supplementary feeding of calves and dams) and culling of non performers could significantly improve reproductive performance of female cattle in the hot humid forest zone of Ghana.
Foraging strategies and some morphometric characteristics of the African Honeybee (Apis mellifera adansonii L) in the humid forest environment
(1991) Adjaloo, Michael Kodwo
The foraging strategies and some important morphometric characters of the African honeybee, Apis iuellifera adansonii were studied in detail in humid forest environment with the view to contributing to a full appreciation of the relative importance of this race in crop pollination and honey production. Twenty-four plant species were identified in three study sites as melliferous plant species. Most of them grow together and flower sequentially; their flowering seasons are sharply defined except for few of them which show some overlap. Some of the plant species provide nectar and pollen while others provide only pollen. The one hour production rates and sugar concentration of field populations were measured to determine diurnal pattern and concentration of nectar. All the plant species had similar diurnal patterns of nectar secretion but differed in nectar standing crop. The sugar concentration of nectar in more open corollas proved much more variable through the day than the concentration in the nectar of the partially or totally concealed nectaries. The foraging pattern of A. m. adansonii on the plant species was analysed, particularly in relation to weather. The results indicated that A.m. adansonii did not differ from other races of honeybee in its response to changes in weather conditions. Its numbers foraging were significantly affected by temperature, and relative humidity. Wet and cloudy conditions also reduced greatly its foraging activity. The relative abundance of A. m. adansonii on the melliferous plant species may partly be influenced by weather conditions. Sixteen morphometric characters of the bee were measured to determine whether any differences exist between populations found in the same ecological zone. The results indicated that the populations sampled were remarkably similar in all these characters. The proboscis which was relatively longer than that of the North African race, enhanced the feeding of A. m. adansonii on nectar in the melliferous flowering plants with exposed or concealed nectaries.
Studies on some aspects of the biology of Cercospora Henningsii Allesch in relation to the Epidemiology of Brown Leap Spot Disease of Cassava (Manihot Esculenta Crantz.) and Tree Cassava (Manihot Glaziovii Muell.-Arg.)
(1991) Antwi-Boasiako, C.
Cercospora henningsii Allesch, causal agent of brown leaf spot of cassava (Manihot esculenta Crantz) and tree cassava (Manihot glaziovii Muell. -Arg.), produces two types of spores named as the macro-conidia and the micro-conidia. (As the names suggest, the former are bigger in size (20 - 120 x 5 - 7.5 μm) and the latter are smaller (8.75 - 17.5 x 3.75 - 7.5 μm). Isolates from each of the varieties of cassava and tree cassava could not be differentiated on the basis of the shapes of their spores. There was, however, a slight variation between the sizes of each type- of spore from the test plants as statistical analysis showed. The micro-conidia were observed to have been formed from the macro- conidia through budding and fragmentation. The frequency of occurrence of each type of spore depended on the time of the year (that is, the season) during which lesions were taken for studies. More micro-conidia were harvested from lesions of each test plant during the wet periods of the year. However, during the dry harmattan periods, fewer numbers of spores were harvested of which the macro—conidia were more frequent. Sporulation of the fungus is sensitive to disinfectants (for - example, mercuric chloride - alcohol solution which was used to sterilize the lesions reduced sporulation). The longer the lesions were exposed to the disinfectant, the fewer the number of spores harvested; macro-conidia were found to be more frequent after lesions have been kept in mercuric chloride - alcohol solution for long periods of time. The micro-conidia became more frequent as the incubation periods on lesions became longer. Successive crops of spores, more frequently the micro-conidia, could be harvested from lesions when they were washed and reincubated for successive periods of time. The lesions, therefore, have a high sporulating potential. Lesions sporulated from 40-100% relative humidity but sporulation was best at 95% and 100% humidity and poorest at 40% and 60% humidity. Latent period of germination for micro-conidia was 4-6 hours and 5-7 hours for the macro-conidia. Diverse forms of appressoria were formed at the apices of germ tubes of the micro-conidia whilst those of macro-conidia had fewer but simple Knob-like forms of appressoria. Germinated spores of each type could produce as many as three germ tubes. Long germ tubes were produced from germinated spores of each type and some of them were as long as 90Ojm when the spores were incubated at 100% humidity for 24 hours. Germination was better on host leaf surfaces than on glass surfaces. Branching of germ tubes could also be stimulated better on host leaf surfaces than on glass surfaces. Conidia germinated from 80-100% humidity. It was, however, best at 100% humidity and percentage germination was better for micro-conidia than for macro- conidia at this level of humidity. Germination of conidia of isolates from cassava and tree cassava was similar. Incubation period on cassava varieties during self-inoculation studies was shorter (12.6 days) whilst that on tree cassava was longer (22.6 days) when leaf-borne conidia of high spore density were used for inoculation through the contact method. Incubation periods were also shorter when abaxial or lower surfaces of red and white varieties of cassava were inoculated using inocula with higher densities. In much the same way, the number of inoculated spots which got infected depended Ofl the concentration of inocula, the variety of host plant and the leaf surface inoculated. More inoculated spots on the varieties of cassava got infected than on tree cassava. During cross-inoculation tests, inocula from cassava could infect tree cassava. Similarly, isolates from tree cassava could infect both varieties of cassava. Tree cassava is a possible source of inoculum for cassava.
Relative toxicity of three synthetic insecticides and a plant-derived insecticide to oreochromis niloticus and some aquatic invertebrates
(1991) Boafo, David
Three synthetic insecticides, Thiodan 35EC, Cymbush 10EC, RoxioN 40EC and a plant-derived insecticide, seed oil were tested against Oreochromis niloticus, Trithemis sp., and Sphaerodema sp. There were no significant differences between the mean weights of the test organisms used for the individual tests (P = 0.05). The temperature of the test solutions for all the test chemicals throughout the test period was in the range of 26°c — 28°C. The pH of the test solutions of Thiodan 35EC and Cymbush 10EC with O. niloticus was 7 throughout the experiments. The dissolved oxygen content of the test solutions ranged from 6.4 mg/l to 7.8 mg/l. The reaction of O. niloticus and the aquatic invertebrates to the various concentrations of the test chemicals was similar; the main symptoms were high excitability, erratic and uncoordinated movements, loss of equilibrium and finally death. The manifestation time generally decreased with increase in the concentration of the test chemicals. The percentage mortality of the test organisms also increased with increase in concentration of the test chemicals. The LC50’s of the synthetic insecticides for the test organisms ranged from 2.66 ppb to 17 782.79 ppb; those of the plant-derived insecticide ranged from 21.13 μl/l to 26.61 μl/l. The LC50’s indicated that O. niloticus is about 4,600 times more susceptible to Thiodan, an organochlorine insecticide, than to Roxion all organophosphate insecticide. Some of the invertebrates, however, were found to the othe tolerant to Thiodan than to Cymbush and Roxion. Sphaerodema sp. was in general more tolerant than the other invertebrates to the synthetic insecticides but more susceptible than the others to the plant-derived insecticide. In general, the order of susceptibility of the various test organisms to the different test chemicals was Thiodan: Berosus sp. > O. niloticus > Sphearrodema sp. > Trithemis sp. Cymbush: Trithemis sp > Berosus sp > Sphearrodema sp. > O. niloticus Roxion: Berosus sp. > Trithemis sp > O. niloticus > Sphearrodema sp J. curcas seed oil: Sphearrodema sp > Berosus sp > Trithemis sp > O. niloticus
Extraction and Refining of Slack Wax from Residual Fuel Oil from Tema Oil Refinery to Produce Petroleum Wax (Paraffin Wax) for Industrial Application
( 1991) Peprah, Lockhart Kofi
Residual fuel oil from Tema oil refinery was fractionally distilled under reduced pressure of 0.001 maHg and two fractions with boiling points range 32-33oC and 33-42oC was collected. The distillates were subjected to urea dewaxing process. The urea adduct was separated into semi-solid hydrocarbon phase (alack wax) and an aqueous urea phase. An appreciable quantity of the slack wax was isplated from the distillate by solvent dewaxing technique using methyl ethylhetone (MIX) – toluene mixture (4:1 v/v). The slack wax was then deoiled using the same solvent system. The deoiled crude wax was subjected to various methods of purification or refinement. The sun bleaching method (as suggested by Root) (36) caused virtually no change in the colour. The wax was, however, successful refined by contact filtration and percolation techniques using carbon tetrachloride, xylane and benzene as solvents. The acid-fuller’s earth’s contact filtration method changed the original pale brown colour to pale yellow with a yield of 47.2%. The wax was, however, balance to white by separately percolating through bauxite, activated charcoal and fuller’s earth. The yield ranged from 75 to 81%.The physiochemical characteristics of the leaches waxes were determined by (ASTN D87); drop melting point (ASTN D127) and congealing point (ASTN D938) methods. The values obtained for the waxes bleached by the different methods differ slightly and ranged from 61-640C; 61.5-64.50C, 60.9-63.9 respectively. The oil content of the wax was determined by ASTN D72 method and the value for the bleached waxes were calculated and found to range from (0.282-0.469). Test for carbonizable substances was carried out on the bleached waxes using D612 method and were found to pass the carbonizable test. The specific gravity was determined by floating wax method and by Archimedes principles employing a sinker. The values for the various waxes ranged from (0.899-0.915; 0.897-0.914) for the above methods respectively. The refractive index was determined on the molten or liquid form of the wax at 800C using Abbe’s Refractometer. The readings ranged from 1.4281-1.4285 for the waxes bleached by the various methods.The molecular weight was determined for all the bleached waxes by means of cryoscopic (freezing point depression) method, - Rest method. The values ranges from (392.85 – 401.0), average being 396.9 g per mole. The physiocochemical property compare better with those of paraffin wax than those of microcrystalline wax.

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