Showing papers by "University of Malaya published in 1971"

The Social Readjustment Rating Scale: A Cross-Cultural Study of Malaysians and Americans

Abstract: Two hundred sixty-six Malaysian medical students were compared with 195 selectively matched Americans on the Social Readjustment Rating Questionnaire. There was a remarkable concordance (Spearman's rho ranged from. 97 to. 91) between the Malaysian and American samples as well as between discrete subgroups in the Malaysian sample in the manner in which they established a relative order of magnitude to changes in life events. Some interesting and profound differences resulting from cultural variations were also observed. Attitudes of the Malaysians toward infringement of laws, the idea of romantic love and thus relationship between spouses seem to differ significantly from the American sample. Malaysians scored significantly higher on items pertaining to personal habits, religious activities, attitudes toward work, and financial security. Differences among Malaysian subgroups (race, religion, sex, year of medical class, and generation Malaysian) were discussed.

Acquisition of conditioned avoidance response in rats under the influence of addicting drugs

Abstract: Four groups of white rats, aged 8–12 weeks, were treated with morphine, d-lysergic acid diethylamide, dl-amphetamine and ethanol, respectively, while being trained in a conditioned avoidance response (CAR) schedule. Morphine caused deterioration in the acquisition of CAR, as manifested by significant increases in the number of training sessions required for 100% correct CAR and in the reaction time (RT), when compared to those of a control group. The RT decreased after withdrawal of morphine and was associated with a revival of the conditioned emotional responses (CER). LSD and ethanol insignificantly retarded the acquisition of CAR, while withdrawal of LSD caused significant increases in the RT, error and CER. Amphetamine facilitated the acquisition rate associated with increased CER; during withdrawal, the CER was negligible whereas the error increased significantly. In another series of rats, tolerance was seen to morphine and, to a less extent, to ethanol and amphetamine after 8–12 days of continued treatment; whereas the withdrawal effects lasted for 3–4 days only. These effects of the addicting drugs on conditioned learning are discussed in the light of their influence on the emotional responses of the animals and the degree of development of drug-dependence.

An inquiry into the genesis of aggression in mice induced by isolation.

Abstract: An easily reproducible method was developed for isolating mice and evaluating isolation-induced aggression. A scoring schedule for rating aggressiveness and a formula to assess the dominance-subordination index (DI) were adopted. Sixty-eight white and black male mice, in 3 series, were socially isolated at 3-6 weeks of age. Increased excitability, hyperkinesia and other behavioural aberrations were observed during the first 6 weeks of isolation after which fighting sessions were started between conspecific pairs of mice. They were placed into 3 grades of aggressiveness on the basis of the scores and DI from 12 fighting sessions for each series. Aggressiveness increased till the 4th to 6th fighting session as the mice gained experience in fighting but decreased thereafter, probably, due to frequent contacts with and habituation to other mice that could be considered as 'socialization'. The respective roles of social isolation in engendering aggression and of socialization in suppressing it were discussed in relevance with the possible mechanisms.

Some Results on the Sampling Distribution of the Multiple Correlation Coefficient

Abstract: Recurrence formulae for the density function and the probability integral of the multiple correlation coefficient from a normal sample are obtained. When the number of independent variates is odd these formulae are related to the distribution of the simple correlation. Asymptotic expansions in terms of the non-central beta and of the non-central x2 distributions are derived. Methods of approximation by the central and the non-central F distributions, as well as by the normal distribution, are proposed. Numerical investigations of the accuracies of these approximations are carried out.

Boron: possible role in plant metabolism.

Abstract: Leaves of boron-deficient oil palm showed a total absence of the leucoanthocyanins usually present, well before onset of pathological symptoms. The association of boron with flavonoid synthesis is consistent with the otherwise anomalous situation that this element is essential for higher plants but not for animals or lower plants.

The effect of the type of feeding on weight gain and illnesses in infants.

Abstract: The effects of breastfeeding and artificial feeding have been analyzed for a group of 250 infants from lower socioeconomic urban families in Kuala Lumpur Malaysia. The factors considered were the ethnic group the sex of the infant the size and income of the family and the type of milk fed. No infant in the study was given "nonmilk" feeds before the age of 40 weeks. The effects of these factors on the weight gains and the number of reported illnesses up to the age of 40 weeks have been analyzed. At no time in the first 40 weeks did breastfed infants gain weight significantly more rapidly than artificially fed infants. After the age of 20 weeks artificially fed infants gained significantly more weight than breastfed infants. The type of feeding had no statistically significant effect on the frequency of minor respiratory or alimentary illnesses. In the community the welfare of the family often depends on the earnings of the mother who has to make the choice between breastfeeding and paid employment. In the group studied breastfeeding appears to offer no advantages over artificial feeding. The guiding principle for the Maternal and Child Health staff when advising the mother should be the welfare of the whole family. (authors modified)

The investigation of samples containing many species: II. Sample comparison

Abstract: A comparison is made between a number of indices of similarity fer describing the similarities between multiple species samples, namely K, I, (1 - z), (x2/AT)1/2, r and a weighted similarity coefficient under various transformations. After discussing theoretical aspects of the indices, they are tested on two sets of data obtained by mist-netting birds. The resulting matrices are sorted by a simple nearest-neighbour agglomerative technique and later by principal component analysis. It is concluded that the V index, which is Kendall's rank correlation coefficient (Kendall, 1955), provides the most meaningful segregation, particularly under principal component analysis. Problems of subjective interpretation are discussed.

Chromosome polymorphism in the Malayan house shrew, Suncus murinus (Insectivora, Soricidae).

Abstract: 15 Exemplare vonSuncus murinus aus Kuala Lumpur und Petaling Jaya, Selangor (Malaysia) zeigten 3 Exemplare mit einer diploiden Zahl von 40, 9 weitere mit 2n=39 und 3 Exemplare mit 2n=38. Der Untrschied der Chromosomenzahl innerhalb einer Intrapopulation wird mit der Robertson'schen Translokation in Zusammenhang gebracht.

Falciparum malaria associated with jaundice, renal failure and anaemia.

Abstract: Three patients were described in whom falciparum malaria was accompanied by severe jaundice, renal failure due to tubular necrosis, and anaemia without overt intravascular haemolysis. Treatment with antimalarial drugs and peritoneal dialysis was successful in 2, but the third patient died from a bleeding peptic ulcer which complicated his illness. The renal failure and other manifestations of the P. falciparum infection are considered in the light of a common toxic factor.

Presumptive X monosomy in black rats from Malaya.

Abstract: DURING a cytogenetic study of the Malayan species of Rattus Fischer, black rats, Rattus rattus diardii (Jentink), were trapped at Kuala Lumpur, Selangor, and Batu Pahat, Johore, between November 1968 and July 1970. Ninety animals were examined cytologically and seventeen gave chromosome counts that differed from the normal diploid number of 42 (ref. 1). Fourteen had between one and three additional small metacentric chromosomes which were not distinguished from normal members of the complement. Nevertheless, they are assumed to be equivalent to the “inert” supernumerary (or B) chromosomes of many invertebrate and plant species. Counts of 41 chromosomes were recorded repeatedly in preparations from four of the rats trapped at Kuala Lumpur. Karyotype analysis indicated that “Robertsonian fusion” between two acrocentric chromosomes had occurred in a male specimen2. In the remaining three specimens (all females) an acrocentric chromosome was absent. Observations were made on preparations from bone marrow.

Haematological data and milk iron in Malaysian women.

Abstract: 45 normal primiparous and multiparous Malaysian parturient women (aged 16 to 34 years) were studied to examine hematological changes during lactation. The women represented 3 ethnic groups: Chinese Indian and Malay. Blood and milk samples collected on the 2nd postpartum day were analyzed using the cyanmethaemoglobin method and bathophenanthroline method as described by Ezekiel. By Western standards hemoglobin values of Malaysian women were relatively high while plasma TIBC (total iron binding capacity) levels were very low. No correlation between total iron-binding capacity of milk whey (presumed to be rich in lactoferrin) and whole milk iron concentrations were found. Milk iron content of Chinese parturient women (mean 81.8 ug per 100 ml milk) was significantly lower than those from the Indian and Malay mothers (P ?0.05). The 3 ethnic groups did not exhibit any significant differences in the hemoglobin hematocrit reticulocyte count plasma iron and whey TIBC levels. The whey iron-binding proteins were approximately 1/3 saturated with iron.

The investigation of samples containing many species: I. Sample description

Abstract: The examination of samples containing many species presents difficulties of description and comparison when the samples are treated as entities. Five different methods of sample description are discussed with special reference to mist-net samples of Malayan birds and it is concluded that the log-series is the most satisfactory with these data. The variation of the index of diversity is examined in time and between habitats and it is concluded that the index provides a measure of habitat diversity in relation to a fauna but may be affected by lack of species preadapted to newly available or expanded habitats. Theoretical and practical features of the various models are also examined.

The relation between dry and fresh weight in some caterpillars

Abstract: The relations between dry (y) and fresh (x) weights of five groups of lepidopteran larvae are all of the form y = axb and can be summarised in a single expression – y = a’ X1.1094 The value of a' differs between groups and appears to vary inversely with maximum fresh (and dry) weights. More data are required to determine whether this relation is truly linear or curvilinear, and at present both a’ = (0.247 xt − 2.865) xt−1.1094 and a’ = 0.2856 xt−0.1825 (where xt = mature larval weight) appear to be adequate. Inaccuracies in these equations may arise from the use of larvae with an unknown quantity of food or faeces in the gut, grouping of more than one species in three of the five groups and the crude estimates of final body-weight. Resume RELATION ENTRE LE POIDS SEC ET LE POIDS FRAIS CHEZ QUELQUES CHENILIES La relation entre le poids frais et le poids sec de chenilles recoltees dans la nature en cours d'alimentation, a ete etudiee d'une part pour quelques especes de Geometrides: Erannis sp., Hydriomena furcata et Operophtera brumaio, d'autre part pour des especes diverses etudiees simultanement et se rapportant aux Noctuidae (Orthosia stabilis et Cosmia trapezina et aux Tortricidae (plusieurs genres). Dans les cinq groupes de chenilles ainsi etudiees, la relation entre le poids sec (y) et le poids frais (x) est de la forme y = axb et peut etre ramene a une meme expression: y = a’ x1.1094. La valeur de a’ differe entre les groupes et semble varier de facon inversement proportionnelle avec la valeur maximum du poids frais (ou du poids sec). Davantage de donnees seront necessaires pour preciser si cette relation est vraiment lineaire ou curvilineaire. Les incertitudes relevees peuvent provenir du fait que l'on n'a pu preciser pour les chenilles etudiees la quantite d'aliment ou de faeces retenue dans le tube digestif et que plusieurs especes ont ete etudiees dans un meme ensemble.

Isotropic radiation from a steadily pulsating multidimensional distribution

Abstract: A multidimensional dynamical configuration is considered, com prising an isotropic homogeneous unbounded medium steadily oscillating in response to a real constant frequency imparted by an embedded source. A Green function to the problem is first derived, and leads to the compounding of the general exact solution for an arbitrary spatial distribution of the source function. Specializations are made to yield an asymptotic solution, a spherically symmetric solution and an axisymmetric solution. All physical results satisfy an initially imposed radiation condition, whose consequence is subsequently accommodated during the construction of the Green function. Significances are attached and interpretations provided, namely, in terms of the associated isotropic waves. A cursory application is made to examine the oscillatory motion, when reduced to the isotropic state, of a rotating magnetoelastic system. An appendix is included to deal with a certain spherical integral encountered during the investigation into the axisymmetric case.

Somatic chromosomes of the flat-headed bats (Tylonycteris spp)

Abstract: Zwei sympatrische, nahverwandte Fledermausarten,Tylonycteris pachypus (Temminck) undT. robustula Thomas, besitzen 46 beziehungsweise 32 Chromosomen, was offenbar den Robertson'schen Translokationen zuzuschreiben ist.

Growth and Productivity of Tapioca ( Manihot utilissima ) II. Stomatal Functioning and Yield

Abstract: The stomatal functioning of high, medium and low yielding clones of tapioca was examined to see whether yield could be associated with conductivity and/or resistance to moisture stress. A sensitive falling pressure porometer was used to measure stomatal conductivity to the viscous flow of air at small pressure differences. No marked differences were observed which could account for the large range in yields shown by the varieties, but stomatal functioning could be related to canopy type and to planting conditions. In general the conductivity values of all three varieties were very low compared to many other crop species, which suggests that increases in canopy efficiency and yield could be obtained in certain environments by an increase in leaf conductivity.

THIOPENTONE-SUXAMETHONIUM MIXTURE: A Method for Reducing the Aspiration Hazard during Induction of Anaesthesia

Abstract: SUMMARY Injection of a thiopentone-suxamethonium mixture is a safe method for rapid intubation in cases where the risk of regurgitation is high. It shortens the period between the onset of unconsciousness and endotracheal intubation. With the technique described the likelihood of awareness of fasciculations is very small. It forms a useful addition to the techniques available for dealing with a patient having a full stomach and it can be combined with other methods of reducing the risk of aspiration during induction of anaesthesia.

Lanthanide Shift Reagents: Acetylacetone Complex of Yb(III) Ion

Abstract: It has recently been shown that the 2,2,6,6-tetra-methylheptane-3,5-dione (tmhd) complexes of a number of lanthanide ions possess the useful property of inducing large chemical shifts in the proton NMR spectra of certain compounds containing OH or other nucleophilic groups1–8 The resulting spectra are frequently more readily assignable and analysable Although europium and praseodymium appear to be the most suitable ions for such studies, the shifting effect is also observed with other lanthanide ions5,6

Dimers from α‐alkoxybenzyl radicals. An NMR study

Abstract: meso and dl Dimers (ArCHOR)2 where R is Me, Et, iPr, tBu, cyclohexyl and 1-adamantyl may readily be differentiated by their NMR spectra; the benzylic protons of the meso isomer always absorb at a slightly higher field than those of the dl isomer in each of the solvents used. Differences in chemical shift are discussed in terms of preferences in conformer distribution. The formation of equal amounts of both dimers from the corresponding radical ArCHOR shows that steric and polar factors are not important in influencing the dimerization. Magnetic non-equivalence due to the presence of asymmetric centres was found in some of the compounds discussed above.

Centric fusion in the Malayan house rat, Rattus rattus diardii (Rodentia, Muridae).

Abstract: Bei einem Mannchen vonRattus rattus diardii aus Kuala Lumpur (Malaysia) wurden 41 Chromosomen (normal 2n = 42) gefunden, was mit der Robertson'schen Translokation in Zusammenhang stehen durfte, welche die Fusion 2 einarmiger Autosomen in ein grosses, zweiarmiges Chromosom vollzieht.