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    EYE LENS PROTEINS AND PHYSICAL PARAMETERS AS TOOLS IN FRESHWATER FISH TAXGNCMIC INFORMATION
    (1964-10) MAHDI, ABDULLAHI
    (1) Length - weight measurements were made on the fish species examined and statistical analysis carried out on the data. (2) Eye lens nuclear proteins were examined electrophoretically. (3) Differences were found between all the species studied and the results obtained indicated significant inter-specific variation. (4) In the electrophoretic study, correlation between the similarity of the electrophoretic patterns and the closeness of the relationship between species was observed. (5) The results indicate that physical parameters and eye lens proteins have considerable potential as sources of taxonomic information.
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    AN INVESTIGATION OP MICROPULSATIONS IN THE EQUATORIAL REGION
    (1968-01) ADAH, MOSE S EGENE
    As an introduction to the thesis, an account is given of the previous observational studies of geomagnetic micropulsations at all latitudes but special attention is given to low latitude studies. Results obtained from both magnetic and earth current records are given in the survey. Reference is made to existing theories concerning the production of micropulsational phenomena, An account is given of the experimental methods for the study of micropulsations and the theory of the action of the high permeability core magnetometer, the type used in Zaria, is given in some detail. This is followed by the experimental particulars and the results of the analysis on pc 3, pc 4 and pi 2 band micropulsations obtained on the rapid-run magnetograms at Zaria for the months of July and August 1967. The. main r e s u l t s includes- (1) The dominant periodic times of pc 3 and pc 4 are (38 -+ 3) sec, and (60 -+ 5) sec, and that of pi 2 is (60 -+ 5) sec. (2) Pc 3 occurs at a l l local times with two peaks in occurrence; one in the morning and the other in the evening, the morning peak at about 06 hrs, (L,T) being more pronounced. Its peak amplitude is near local noon. (3) Pc 4 is essentially a daytime phenomenon with peak occurrence and amplitude near local noon, {4) Pi 2 is essentially a night time phenomenon with •peak occurrence between 22 and 23 hrs (LIT.) (5) Micropulsation activity is enhanced during magnetically disturbed periods and the amplitude is larger in the H than in the D component. (6) Pc 3, pc 4 and pi 2 micropulsations are linearly polarized along the magnetic meridian. The observed periods are compared with resonant periods predicted by some resonance theories for low latitudes. Also, the results obtained on pc 3, pc 4 and pi 2 band micropulsations are compared with those previously obtained at low latitudes.
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    THE ABSORPTION OF NAPHTHOL DERIVATIVES BY CELLULOSIC FIBRES.
    (1968-07) Atanu, Emmanuel Yahaya
    The azoic dyes are obtained by coupling between, a naphthalene derivative end a diazotized amine The naphthalene derivative is referred to variously as a coupling component, arylamide or by its commercial name e.g. Breathol, Naphthol, etc. It is first adsorbed onto the textile material and the desired colour developed by immersing the fibre or fabric in a solution of the appropriate diazotized amine. The depth of the shade depends mainly on the amount of coupling component adsorbed on the fibre, prior to colour development. The scope of the present work was to study the uptake of these compounds by cellulosic fibres under various conditions e.g. different alkali, salt and naphthol concentrations; temperature; and the effect of modifying the cellulose structure on absorption. It was also thought that a possible mechanism for the combination of naphthol with cellulose could be worked out and an attempt made to see if the general laws of sorption of solids from solution could be applied to the cellulose naphthol system. As an introduction to the thesis an account is first given of the structure of cellulosic fibres, describing in outline the early theories of fine structure and the concept of crystallinity and accessibility and their relation to the absorption of dyes and other molecules by cellulosio fibres. An account is also given of the principal results of previous studies on the absorption of arylamides and direct dyes by cellulose. The abaorption of free alkali (the solvent for the Naphthols) was first studied, followed by napthol absorption under various conditions by the different cellulose samples. The sain results of the present investigations indicate that: 1) the hydroxyl groups of the cellulose chain are mainly responsible for naphthol absorption as shown by the reduction in absorption when these are oonverted to carbosyl groups. 2) primary hydroxyl groups account for higher equilibrium absorption than secondary ones. 3l oxidation of the hydroxyl groups reduces absorption. 4) opening up the cellulose structure by mereerization increases considerably the absorptive capacity of cellulose. The absorption of two naphthols by standard cellulose at different starting concentrations was also studied and the results used to test several adsorption theories. Agreement was obtained for the treatment of Saruwalla and Kulkarni leading to the suggested mechanism that only the dye anions are adsorbed on specifio sites, while the sodium ions are diffusely adsorbed. The treatment adopting Hill's statistical approach also yielded a positive agreement. The concurrence of the theories tested lies in the fact that their formulation depends on the basic assumption of an initial monolayer absorption on which is superimposed a diffuse layer.
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    STUDIES IN THE TRANSFORMATION OF STEROIDS
    (1968-12) SAMUEL, ADENIYI IBIYEMI
    A series of experiments were planned to convert a steroid into a tetracyclic triterpenoid. As preliminary to these experiments, a number of systematic reactions of related types and conpounds were carried out. N-Monoand Di-alkylation of a primary aromatic amine (1-naphthy1amine) was f i r s t carried out. Next alkylation with different alkyl groups on different types of hydroxyl groups were conducted, Alkylation was done with methyl and ethyl groups on phenolic as well as carboxylic hydroxyl groups, AS podocarpic acid contains both these types of hydroxyl groups, that was the model compound taken for these experiments, Six out of the eight possible forms of the mone and dialkylated products with the two different alkyl groups and the two different hydroxyl groups of podocarpic acid were prepared and characterized. Three experiments were conducted to convert cholesterol into a nor compound by removing the methylene group at C4 and converting ring A into a six membered ether. An A/B trans rused and A/B cis fused ether were planned. Out of t h i s , the A/B-trans fused ether was prepared by oxidizing cholesterol to cholesteaone, further oxidizing cholestenone to a ring A a-lactone, then reducing this lactone to a diol and then cyclising this diol to a o-membered ether.
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    THE INFLUENCE OF URBAN-RURAL ORIENTATION, LENGTH OF RESIDENCE AND LEVEL OF COMMUNITY DEVELOPMENT ON SOCIAL INTERACTION IN THE URBAN-RURAL FRINGE IN UPSTATE NEW YORK
    (1969-09) Durrani, Tariq Masud
    The urban-rural fringe in the metropolitan areas of the United States seems to be experiencing the same cycle of growth as the suburbs did in the past: a progression from rural to mixed rural-urban to suburban land uses and an infusion of an urbanized life style. The crucial point, however, is not that the areas become "suburbs" but that they become integrated with the city. Since these communities undergo a change in their character while in the process of transformation from rural to "suburban," it is believed that changes also take place in the amount and nature of social interaction in these communities. Questions have been raised regarding whether or not social life would be disrupted in rapidly growing fringe communities. Would social interaction continue with friends and relatives in the place of origin or will new patterns rapidly develop? Such questions are of great importance for an understanding of the current trends in present fringe and for planning of future development. This study analyzed social interaction in the context of three different communities at various levels of fringe development. One of these areas was in an early stage of development, another one in an advanced stage and the third area was in the final stage of development toward suburbanization and integration into the metropolitan area. It is to be expected that the amount of social interaction in the fringe is influenced by one's community orientation (rural or urban) and length of residence in an area. It is known that rural- and urbanoriented people differ in the amount and type of social interaction they engage in, and that over a period of time not only do the fringe areas vi develop in terms of changes in social patterns but the level of interaction also changes for individual residents with increased time in the area. It was found that in general the length of residence had greater Influence on the amount of social interaction than community orientation. In the most developed of the three areas, even this distinction faded out. Generally, socioeconomic status and stage in the family life cycle had only small effect on the amount of interaction in these areas. However, in some specific aspects of social interaction, variations were found arising from differential community orientation and length of residence. Generally, in all areas studied, people in the "high" socioeconomic class showed greater institutional participation than those in the "middle" or "low" classes. In the more developed areas, the middle aged respondents showed greater institutional participation than the young and the aged. However, in the less developed area, participation levels were less clearly influenced by family life cycle stage. Most respondents, regardless of community orientation, socioeconomic class or stage in the family life cycle, expressed great satisfaction with fringe residence. The present day fringe area is far from being an "institutional desert." Those who have opted to live there become part of the community to a great extent. Long-time residents seemed to be more active in the social life of the area while newcomers were more active in its institutional life. Higher levels of development of a community have been • • • • vii shown to reduce the differences between rural- and urban-oriented residents in various specific aspects of social interaction and institutional participation.
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    ESTIMATION OF ANNUAL GENETICALLY SIGNIFICANT DOSE FROM DIAGNOSTIC RADIOGRAPHY IN KADUNA STATE
    (1970) MOKOBIA, C.E.,
    The generically significant dose from X-ray diagnostic procedures has been determined in many countries. For the estimation of the annual genetically significant dose from X-ray radiography in Kaduna state the age and sex distributions of patients who under-went five diagnostic examinations were obtained from, X-ray depart rents of four sample hospitals. Entrance exposures to the skin were measured using free- in air method. Organ doses were then estimated using Protein's "Handbook of selected Organ Doses for projections Common in Diagnostic Radiology." Child expectancies for various age-sex groups in Kaduna state were calculated by combining the number of members of a cohort surviving to reach successive age bands of Specified duration with the age specific maternity/ paternity rates. The maximum child expectancies for the sexes were found to be 2.97 and 1.98 for males and females respectively. The annual Gs d from diagnostic radiography for five examinations was then estimated by combining the age-sex distributions with child expectancies and gonadal doses per person per examination. The annual GS D for Kaduna state was estimated to be 37.4.± 3.9 μGy.
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    INTRACTION OF SODIUM , CALCIUM AND MAGNESIUM IONS WITH DEOXYRIBONUCLEIC ACID
    (1971-03) OlAYEMI, JULIUS YINKA
    The i n t e r a c t i o n of sodium ( i ) , polonium (ii) and magnesium ( I I) with Ribonucleic acid (DNA) of oaf thymus has been studied by d i a l y s i s equilibrium, conductance measurements, u l t r a v i o l et l i g h t absorption and l i g h t s c a t t e r i n g methods. The r e s u l t s have been summarized as follows: ( i ) DNA i n t e r a c t s with sodium, calcium and magnesium ions and more strongly with the two divalent c a t i o n s. ( i i ) Magnesium and calcium ions bind q u a n t i t a t i v e l y to DNA to form complexes of the following optometrists: 0.125:; 0.30:1 and 0.50:1 moles of divalent cation to one mole of nucleate phosphorus. In a l k a l i n e medium, a 1:1 mole complex was formed. ( i i i ) The s t a b i l i t y of the complexes formed between the divalent cations and DNA depends on (a) the concentration of sodium chloride supporting e l e c t r o l y t e , and ( b ) , the pH of the s o l u t i o n . The s t a ability decreases with increasing s a l t concentration and with increasing a c i d i t y f o r each DNA-M2+ system. The s t a b i l i t y constants for the DNA-Mg complexes are comparable with those of DNA-Ca2+ complexes. ( i v ) At room temperature, DNA r e t a i n s i t s n a t i v e s t r u c t u r e when prepared in s o l u t i o n of sodium chloride of at l e a s t 1 0 - 4 a n d in both caloric and magnesium chloride of about one hundredth of t h is concentration. The molar absorptivity e(P) of DNA becomes a function of the concentration of NaCl2 CaCl2 and HgClp only when the acid is denatured, but is completely independent of salt concentration when in i t s native form. DNA naturalization temperature (Tm) is increased in the presence of increasing concentrations of NaCl, CaCl2 and MgC2. Calcium and magnesium ions are more effective than the sodium ions in causing this increase in (Tm), showing a stronger interaction of the divalent orations than of the covalent sodium ions with DNA. Low concentration of calcium and magnesium ions (of the order of and below) have no destructive influence on the secondary structure of DNA. However, high concentrations of these divalent orations (of the order of 0.05H and above) have been suspected to produce a naturalization followed by a precipitation and/or aggregation of a system of DNA-M on heating beyond the naturalization temperature (Tm). (v) The method of light scattering has shown that the molecular weight of DNA depends on the concentrations of calcium and magnesium ions up to a certain maximum concentration of these orations, when the molecular weight of the DNA is doubled. This suggests that calcium and magnesium ions are engaged in an intermolecular bonding to DNA. The molecular weight of DNA was found to be independent of the concentration of sodium ions
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    "KINETIC STUDIES OF THE AQUATION OF SOME NITRO AMINE COBALT (III) COMPLEXES USING METAL IONS AS CATALYSTS"
    (1971-09) OLATUNJI, MOBOLANLE ADEGBOYEGA
    The mercury (ii) and thallium (ill) catalysed aquation of transdinitrotetrammine Cobalt (ill) and trans-dinitrobisethylenediamine Cobalt (ill) nitrates have been studied over a wide temperature range of 30 "to 50 C at various constant hydrogen ion concentrations of between 0,1 to 1.8 M. The ionic strength of the different reactions were also kept constant between 0.2 to 2,0 M. In the cation concentration range used [0.01 to 0.30 M] the increase in rate in the different reactions with the exception of the one involving [Co(NH3 )4 (N02)2] N03 and Tl3+ were interpreted in terms of two complex species - a protonated species [co(AA)2(N02)(N02H]2+ and a cation associated species [CO(AA)2(N0 ) n+1 (N02M)J] . Reaction rate constants have been ubteined and thermodynamic parameters derived for all the reactions. For the reaction of the transdinitrotetrammine Cobalt (ill) complex using mercury (II) as catalyst, the activation energies and entropies of activation are as follows: Using thallium (ill) as catalyst for the same complex the calculated activation energy and entropy of activation for the thallium (ill) associated species at 25 are: Ea = 16.6 k cals/mole; A 6 = -6.80 e.u. Under the hydrogen ion concentration used, no reaction due to the protonated species was observed. However an initial fast reaction which was attributed to the hydroxide catalysed reaction was observed. In the case of trans-dinitrobisethylenediamine Cobalt (ill) complex, two intermediate complex species were involved in all the reactions involving the two metal ions. For the mercury (il) catalysed aquation,
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    OME REACTIONS 0F NN - DISUBSTITUTED THIOAMIDES
    (1973-01) OKECHA, STEPHEN AGWO
    In the present work some of the synthetic applications of S-alkyl quaternary salts of NK-disub¬stituted thioamides were investigated, NN-Disubstituted tliioamides which were prepared by the Willgerodt Klndler procedure, 1-8 or from the amides with phosphorus pentasulphide9 were reacted With simple alkyl halides to give S-alkyl quaternary salts in good yields. The reaction of the quaternary salts With hydroxy 1amine hydrochloride produced NN-disubstituted amidoximes, while treatment of the quaternary salts with potassium cyanide gave novel S-alkyl quaternary cyanides some of which hydrolysed to cyanoamides under surprisingly mild conditions
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    THE EFFECT OF 4-NITROQUINOLINE 1-OXIDE ON THE UPTAKE AND INCORPORATION OF SELECTED AMINO ACIDS BY LACTOBACILLUS CASEI
    (1973-05) Barker, Charles Lawrence
    Utilizing Lactobacilling casei cells an experimental teat system was developed to measure the effect of varying concentrations of the potent, water-soluble, oncogen 4-nitroquinoline 1-oxide (4-4Q0) on amino acid uptake and Incorporation by the bacteria. The rates of uptake, incorporation, and removal of tritium labeled 4-NQ0 were measured. Clycine-14C, L-alauine-14C, L-methionine-14C, and L-tyrosine-14C standard uptake and Incorporration measurements wore also taken. The labeled aaiino acids all displayed a rapid Initial uptake with saturation being almost completed after 180 seconds. The 4-UQ0-3H uptake was initially rapid, reaching a maximum limit after approximately 60 seconds, after which an equally rapid renoval of tritium label was experienced. After 180 seconds from the time of oncogen introduction the bacteria had returned to a bound oncogen label approximately one sixth of the maximum level. The standard incorporated amino acid curves showed a time dependency with maximum levels being reached after 10 minutes. Incorporated oncogen showed an initial level that was approximately twice as high as the level measured after 180 or 600 seconds. Of the amino acids tested L-alanine-14C was the most Sensitive to 4-NQ0 levels. When C.0167 mM 4-NQ0 was introduced Into the test system reduction of L-alanine-14C uptake was noted. Incorporation of the same amino acid was stimulated. In general, the same results were shown for the other amino acids though they we re less sensitive to the presence of oncogen. An alteration in the amino acid incorporation curves, deaonst rating an apparent dependence on the amino acid concentration in the cell and not on time , was noted in all of the data. From the data presented a mechanists for the alteration of biological systems by 4-nitroquinollne l-oxide was given. The reasoning suggests that an alteration of the messenger ribonucleic acid may be the point of initial metabolic change. Other known oncogens we re also introduced into the experimental system. They were N-cicrosodimethylamine and X-nethyl-N'nitro-N'-nitrosoguanidine. Both chemicals induced a simllar aIteration of the standard L-alanine-14C incorporation demonstrated by 4-NQ0. These data suggest that this system may be used to screen potential oncogens.
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    RESIN FINISH TO CELLULOSIC FABRICS
    (1973-05) YABANI, ADAMU MOHAMMED
    The present study deals with the reactions of formaldehyde, dimethylol urea and two commercial resins, aimethylolethylene urea (ARK NG) and a bis-carboamate derivative (ARK CA) with standard cellulose and various oxycelluloses under varying conditions and the effect of these reactions on the crease recovery and tensile strengths of these celluloses. It has been found t h a t : - (a) The % add-on of formaldehyde and the other resins to standard and. nitrogen dioxide oxycellulose depend very much on the catalyst used. The efficiency of the c a t a l y s t s decrease in the order HCl>MgCl2.6H2O> Zn(N03)2.6H20 which is related to the acidity of their solutions. It has also been found that divalent metal s a l t s which are generally used as catalysts release hydrogen ions by the binding of the metal ion to the carboxyl groups in cellulose. T he loss in t e n s i le strength is maximum for hydrochloric acid catalyst probably due to hydrolytic degradation. (b) Oxidation of the cellulose structure with nitrogen dioxide leads to decreases in % add-on of formaldehyde and various other resins. Losses are also observed in crease recovery angle values and t e n s i l e strengths. However, addition of sodium chloride even of as small a concentration as 0.001M to the reaction bath increases the add-on of formaldehyde to both standard and oxycellulose, (c) Oxidation of the cellulose structure with sodium metaperiodate r e s u l t s in an increase in CRA value even without resin treatment. Higher increase in CRA value is observed when such an oxycellulose was cured at 1500 C than when it was "boiled in water. It is thought that cross-1inking occurs through hemiacetal bond formation. Loss in tensile strength is r e l a t i v e l y lower than for nitrogen dioxide oxycellulose. d) Cross-linking periodate oxycellulose with various resins leads to further increases in CRA values. (e) Borohydride reduction of periodate oxycellulose produces an increase in resin add-on as would be expected from the increase in available hydroxyl groups. However, decreases in CRA values and tensile strengths were observed.
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    A Detailed Study of Adventive Embryogenesis in the Rutaceae
    (1973-06) Esan, Edward Babatunde
    A Detailed Study of Adventive Embryogenesis in the Rutaceae by Edward Babatunde Esan Doctor of Philosophy Graduate Program in Botany University of California, Riverside, June, 1973 Professor Toshio Murashige, Chairman This research explored the mechanism underlying the regulation of adventive embryogenesis in plants, using members of the Rutaceae in tests. A histological comparison of Ethrog citron, a monoembryonic cultivar, and Ponkan mandarin, a polyembryonic cultivar, disclosed no information relevant to the research objective. Embryogenesis in vivo in the monoembryonic cultivar followed the pattern typical of most dicot plants. No nucellar embryogenesis occurred in the citron. The zygote of the polyembryonic mandarin was not seen to divide. Meristematic activity began in the nucellus prior to zygote division and resulted in adventive embryogenesis all round the embryo sac. No embryos formed from the nucellus epidermis. The multiplication of embryos in the mandarin occurred largely by budding of existing embryos, rather than continued differentiation among nucellus cells. The histogenic pattern of polyembryogeny in Ponkan mandarin nucellus culture was the same as that in vivo. Nucellar embryogenesis in vitro in the monoembryonic citron cultivar was confined to the micropylar region. Callus formation was not a prerequisite for adventive embryogenesis in either cultivar. Occasionally, a suspensor was observed in nucellar embryos. Fruits obtained during the fall and winter months provided best nucellus explants and those of spring months poorest. Best explants were obtained when a transverse incision was made in the nucellus at some distance from the micropylar region for the purpose of removing embryos. Maximum embryogenesis occurred when the nucellus explant was placed in culture with its chalazal end embedded in agar. Light was not necessary for embryogenesis in vitro. Nucellar embryos were obtained in ovules excised from flower buds of several members of the Rutaceae, without prior pollination. Test of effects of exogenous substances on nucellus cultures was conducted with the monoembryonic cultivars, Ethrog citron and Ponderosa lemon, and the moderately polyembryonic cultivar Eureka lemon. Embryos were obtained in an agar medium containing only Murashige-Skoog salts and sucrose. No addition of hormonal substances or extracts of natural complexes showed significant benefit. Of 31 members of the Rutaceae examined, all except one produced adventive embryos in their nucellus cultures. The members differed only in degree of expression of polyembryogeny in vitro. The micropylar half of a nucellus was clearly more prone to undergo nucellar embryogenesis than the chalazal half. Reciprocal grafts of micropylar halves of polyembryonic and monoembryonic cultivars resulted in no influence on embryogenesis by the one type on the other. In grafts made between the micropylar half of the nucellus of polyembryonic cultivars and the chalazal half of a monoembryonic cultivar, embryogenesis in the normally polyembryonic cultivar was markedly suppressed. This suggested that an embryogenic suppressant was involved in the difference observed in degree of polyembryony among the Rutaceae and between the micropylar and chalazal regions of a nucellus. The embryogenic suppressant was graft transmissible and diffusable through agar. Its effect was irreversible. This substance(s) also suppressed embryogenesis in callus cultures of the wild carrot.
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    TRACTION OF COPPER AND ZINC IONS WITH POLYMETHACRYLIC ACID (PMA)
    (1974-04) EMMANUEL, GBADEBO KOLAWOLE
    The interaction between polymethacrylic acid (PMA) and divalent metal ions has been studied at 25 oC and. varying conditions of ionic strength, polymer concentration, cation concentration and degree of ionization by different experimental techniques. The experimental techniques used were conductance measurements, viscometric t i t r a t i o n , spectrophotometric t i t r a t i o n , dialysis equilibrium, potentiometric t i t r a - tion and light scattering. Data from different experimental methods reveal that both copper and zinc interact quite strongly with preionized PMA to form complexes. Copper has been found to he a stronger hinder than zinc. Copper ions bind PMA to form complexes involving four, two and one carboxylate groups per copper ion while zinc forms complexes involving two and one carhoxylate groups per zinc ion. FMA molecules exist in t i g h t l y coiled state when unneutralized or at low degrees of ionization (0.1>α). The ionized molecules undergo a configurations! trans i t i o n in the range 0.1 < α <0.27. The t r a n s i t i o n is completed at a = 0.27. Maximum chain extension has been achieved at 70% n e u t r a l i z a t i o n . The uncoiling of the polymer molecule has been attributed to strong e l e c t r o s t a t i c repulsive forces between the charged carboxylate groups along the polymer backbone. The uncoiling of the compact PMA molecules is a single-step process. It has been established that some experimental techniques used were more sensitive than others. With conductance measurements, spectrophotometry and potentiometric t i t r a t i o n s it is quite possible to detect almost all types of complex species present in M2+ -PMA systems with their corresponding co-ordination numbers, while viscometric t i t r a t i o n s and d i a l y s i s equilibrium will only detect the most stable complex formed and the corresponding co-ordination number. The r e s u l t s presented in chapter 4 for spectrophotometries t i t r a t i o n s show that Cu2+-FMA complexes are charge-transfer complexes. In chapter 5, equations were derived for M2+ PMA systems to enable the author t o c a l c u l a t e the s t a b i l i ty c o n s t a n t s and the c o - o r d i n a t i o n numbers of complexes formed. These e q u a t i o n s were t e s t e d g r a p h i c a l l y and t h e r e was s a t i s f a c t o r y agreement between t h e o r y and e x p e r i m e n t . It was found t h a t , on t h e a v e r a g e , each c a t i o n formed complexes i n v o l v i n g two c a r b o x y l a t e groups per metal ion and t h a t t h e mode of b i n d i n g could be e i t h e r i n t r a m o l e c u l a r l y or i n t r a m o l e c u l a r l y depending on the i o n i c s t r e n g t h and d e g r e e of i o n i z a t i o n ( a ). I t has been shown c o n v i n c i n g l y in c h a p t e r 6 t h at t h e acid d i s s o c i a t i o n c o n s t a n t Ka is not a c o n s t a n t but a function of a. Potentiometric behaviour of PMA in t h e absence and in the presence of d i v a l e n t c a t i o ns has been d i s c u s s e d in l i g h t of double l a y e r e f f e ct and a l s o in l i g h t of t h e e m p i r i c a l e q u a t i o n s developed for calculating [coo-]bound and [M2+]bound. Light s c a t t e r i n g s t u d i e s confirm t h a t at low d e g r e e s of i o n i z a t i o n a dimer is formed in t h e p r e s e n ce of Cu2 + and Zn2 + ions because the molecular weight is a p p r o x i m a t e l y doubled. This s u g g e s t s t h a t the most l i k e l y mode of b i n d i n g is i n t e r m o l e c u l a r l y . Light s c a t t e r i n g s t u d i e s a l s o confirm t h a t p a r t i a l ly i o n i z e d PMA m o l e c u l e s e x i s t in random c o i l s. Finally in chapter 8, the results obtained from different chapters are compared and the interpretation and deductions made are found to corroborate. Cumulative constants 3 have been calculated for the various complex species in the reaction mixture.
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    YORUBA HOUSEFORM
    (1974-04) Balogun, Olaniran Wilson
    Yoruba houses, like those of the various cultural groups in tropical Africa, are generally thought to be a mere place of abode and shelter from the tropical downpour and the sun. This is a physical environmental view which underestimates the importance of the socio-cultural values of the Yoruba in house formation. The Yoruba household is considered in this paper to be a structured, socio-cultural institution which has three important components. The overriding influence of the lineage ancestor on the household makes up the first component, and this is considered to be the spiritual foundation of the institution. The head of the lineage forms a link between the ancestor and the living members. He ensures maximum cohesion among the extended family members through the exercise of his legislative, judicial and administrative powers. The roles of the lineage head constitute the second component of the institution, i.e., the administrative component. The complex socio-economic interactions among the members of the extended family make up the third component. These three main components jointly determine the siting of Yoruba houses, the various building and space-formation elements of the house, the processes of construction and the materials used for building. Thus socio-cultural factors, as opposed to physical environmental ones, are considered to be the primary forces that create Yoruba house forms.