Showing papers by "National University of Singapore published in 1976"
TL;DR: In this article, the finite element method is applied to calculate the temperatures in orthogonal machining with account being taken of the finite plastic zones, in which the chip is formed and in which further plastic flow occurs at the tool-chip interface, and also of the shape and thermal properties of the cutting tool.
148 citations
TL;DR: In treatment of long-standing cases, only fusion without posterior decompression should be done and in the performance of atlanto-axial fusion, the technique of bone grafting and the use of thick wires need emphasis.
Abstract: A review of 26 cases of odontoid fractures has been carried out. Late diagnosis and consequent delay in treatment were found to be important causes of non-union. Myelopathy in odontoid fractures is of two types. One type is that present immediately after injury, while the other is delayed. In treatment of long-standing cases, only fusion without posterior decompression should be done. If the latter procedure is carried out, it can produce medullospinal haematomyelia with respiratory arrest and tetraplegia. In the performance of atlanto-axial fusion, the technique of bone grafting and the use of thick wires need emphasis.
73 citations
TL;DR: The analysis shows that the “Principle of Minimal Total Muscular Force” is unlikely to be true.
61 citations
42 citations
TL;DR: It is shown that the calculations of spreading resistance correction factors for graded structures can be readily carried out by using a simple recurrence formula for the integration factor that occurs in Schumann and Gardner's multilayer theory.
Abstract: It is shown that the calculations of spreading resistance correction factors for graded structures can be readily carried out by using a simple recurrence formula for the integration factor that occurs in Schumann and Gardner's multilayer theory. The number of layers that can be used in the practical application of this theory has hitherto been limited by the computer core size requirement, because the earlier method of calculating the integration factor requires the inversion of a 2N × 2N matrix for an N-layer approximation. The use of the recurrence formula effectively removes this constraint. In terms of computation time, the recurrence-formula method is also very efficient. The economy thus achieved both in computation time and in core size requirement makes it possible now to make spreading resistance correction a routine matter, without having to resort to such measures as Hu's interpolation and space partitioning scheme.
37 citations
TL;DR: The results show that prostaglandin E2 is effective in promoting the healing of gastric ulcers.
Abstract: Summary: Effect of prostaglandin E2 on the healing of gastric ulcers: A double-blind endoscopic trial. Wye-Poh Fung and Sultan M. M. Karim, Aust. N.Z. J. Med., 1976. 6, pp. 121–122.
A double-blind trial was performed to assess the effect of prostaglandin E2 on the healing of gastric ulcers. The prostaglandin preparation was given orally in doses of 1 mg, 6 hourly for two weeks to ten subjects with proven gastric ulcer. The control group consisted of ten subjects with proven gastric ulcer, without prostaglandin treatment. Gastric ulcer healing was assessed endoscopically with a duodenofiberscope. The maximum diameter of the ulcer crater was determined endoscopically just before and after two weeks of treatment. In the prostaglandin group, complete healing was seen in two cases, considerable healing (50% and more) in three cases, and the overall mean healing rate was 42%. In the control group, complete healing was seen in none, considerable healing in one case, and the overall mean healing rate was 14.3%. The difference, statistically, was significant. The results show that prostaglandin E2 is effective in promoting the healing of gastric ulcers.
33 citations
TL;DR: CMI functions of treated “remission” NPC patients were found to be impaired to the same extent as those of untreated NPC patients.
Abstract: General cell-mediated immune (CMI) functions in NPC patients were investigated by the in vitro Mantoux and in vitro lymphocyte response to PHA assays. Thirty-eight (50%) of 76 untreated NPC patients were hyporesponsive in the Mantoux assay compared to 27 (25%) of 110 control patients. Forty-three (65.2%) of 66 untreated NPC patients also showed lymphocyte hyporesponsiveness to PHA compared to 15 (15.5%) of 97 control patients. Combined deficiencies were observed in 35 (42.2%) of 83 NPC patients compared to only 2 (3.3%) of 61 control patients. No difference in the frequency of immuno-deficiency was observed between “early” and “late” disease patients. CMI functions of treated “remission” NPC patients were found to be impaired to the same extent as those of untreated NPC patients.
Alteration De L'immunite Generale A Mediation Cellulaire In Vivo Et In Vitro Dans Des Cas De Cancer Du Nasopharynx
L'immunite generale a mediation cellulaire (CMI) a ete etudiee dans des cas de cancer du nasopharynx par l'epreuve de Mantoux in vitro et la reponse des lymphocytes a la PHA in vitro. Chez 38 (50%) des 76 malades NPC non traites, on a constate une hyporeaction dans l'epreuve de Mantoux, qui n'apparaissait que chez 27 (25%) des 110 temoins. Chez 43 (65.2%) des 66 malades NPC non traites, on a observe une hypo-reaction des lymphocytes a la PHA, qui n'apparaissait que chez 15 (15.5%) des 97 temoins. Des deficiences dans les deux tests ont ete relevees chez 35 (42.2%) des 83 malades NPC et seulement chez 2 (3.3%) des 61 temoins. On n'a note aucune difference de la frequence des immunodeficiences entre les malades au stade “precoce” ou “tardif”. Chez les malades traites “en remission”, la CMI etait aussi alteree que chez les malades NPC non traites.
30 citations
TL;DR: It is concluded that the differences in the histologic‐specific incidence rates of lung cancer among the various Chinese dialect groups in Singapore are real and not artefactual.
Abstract: Significant differences in the incidence levels of lung cancer have been observed among major Chinese dialect groups or communities (Kokkien, Teochew and Cantonese) in Singapore. Among males, the incidence rate is highest in the Hokkiens (age-standardized incidence rate per 100,000 persons per year in Hokkien 67.8, Teochew 55.3, Cantonese 54.0) and among females, it is highest in the Cantonese (Hokkien 12.4, Teochew 12.8, Cantonese 27.2). The present investigation was undertaken to determine the incidence rates of each of the main histological types of lung cancer in the Chinese population and to determine whether there are any correlations between histological patterns and the dialect group differentials that may be of aetiological significance. During the period 1968-1972, a total of 1,747 cases of lung cancer (1,285 males and 462 females) were reported to the Singapore Cancer Registry. It proved possible to type the neoplasms histologically in 476 males (37.0%) and 154 females (33.3%). Age-standardized rates by histological type were computed on the assumption that those histologically typed were a representative sample of all lung cancers. This study shows that Hokkien males have a significantly higher incidence rate of epidermoid carcinoma than the other dialect groups (Hokkien 36.1, Teochew 21.1, Cantonese 17.3). The Cantonese females have significantly higher incidence rates of both epidermoid carcinoma (Hokkien 3.7, Teochew 2.3, Cantonese 5.9) and adenocarcinoma (Hokkien 4.6, Teochew 3.6, Cantonese 11.9). Various sources of bias in studied of this type were examined; it is concluded that the differences in the histologic-specific incidence rates of lung cancer among the various Chinese dialect groups in Singapore are real and not artefactual. The significance of these findings in relation to possible aetiological factors is discussed.
29 citations
TL;DR: It is suggested that during human labor free fatty acids are the principal metabolic fuel and may serve to spare glucose as a metabolic fuel in the fetus.
Abstract: This investigation was performed to study the metabolism of the major body fuels (viz. glucose and free fatty acids), insulin, and lactic acid during the stress of human labor. In addition, the role of the normal placenta in the transport of these substances between mother and the fetus was evaluated by measuring them in the mother and cord blood at delivery. To study possible alterations of this role in the placenta which had exceeded the normal period of gestation, a second comparable group of women had labor induced with oxytocin 16–18 days beyond the expected date of delivery. A dramatic twofold increase in maternal plasma free fatty acids was observed during labor. There was a lesser but definite increase in blood glucose concentrations. No rise in serum insulin levels was noted which coincided with the changes in blood glucose. Lactic acid concentrations during the course of labor were variable from baseline but at delivery, the concentrations rose to very significant levels. Free fatty acids and blood glucose levels were significantly higher in the maternal than in the fetal side. A significantly positive correlation was noted between the maternal and cord blood values except for free fatty acids in the postmature group. No significant difference, nor a correlation was found between the two compartments in the insulin nor lactic acid levels. These results suggest that during human labor free fatty acids are the principal metabolic fuel. This increase in maternal free fatty acids may serve to spare glucose as a metabolic fuel in the fetus. The mechanism responsible for the increase maternal free fatty acid mobilization remains to be determined. It is not possible to discern any consistant alteration in placental function as a consequence of prolonged gestation.
29 citations
TL;DR: Trans-2-Phenylcyclopropylamine, a monoamine oxidase inhibitor, was added as a routine to the enzyme preparation, as its omission resulted in the production of p-hydroxyphenylacetic acid in appreciable amounts, but did not decrease the sulpho-conjugation of tyramine.
Abstract: Tyramine was conjugated with sulphate by extracts of monkey intestine and livers of monkey, rat, mouse, guinea pig and man. The activity measured in monkey intestine was almost three times that of monkey liver. Labelled tyramine sulphate synthesized from [14C] tyramine, [3H] tyramine or Na235SO4, on acid hydrolysis, released its radioactive precursor. Liver extracts of monkey, rat, mouse and guinea pig synthesized respectively 145,66,21 and 6 pmol of [14C] tyramine sulphate/min per mg of protein. Except with the monkey, intestine exhibited very low activity. trans-2-Phenylcyclopropylamine, a monoamine oxidase inhibitor, was added as a routine to the enzyme preparation, as its omission resulted in the production of p-hydroxyphenylacetic acid in appreciable amounts. This oxidative deamination of tyramine, however, did not decrease the sulpho-conjugation of tyramine. The low Km (9.1 muM) of sulphotransferase for tyramine is probably responsible.
22 citations
TL;DR: In this paper, the authors considered the resistance of an infinite slab of material with a disc contact source on one side and with current collected over the entire back plane, and solved the problem in terms of a pair of dual integral equations.
Abstract: We consider the resistance of an infinite slab of material with a disc contact source on one side and with current collected over the entire back plane. By imposing the boundary condition of a constant potential over the source region, the problem becomes one of mixed boundary conditions, requiring the solution of a pair of dual integral equations. These equations are solved in terms of a Fredholm integral equation of the second kind. Calculations of the resistance are performed for values of slab thicknesses ranging from 0·05 to 4 times the disc contact radius, and the solutions obtained agree closely with Foxhall and Lewis' electrolytic tank measurements. The results are used to establish the range of validity of two approximate methods previously proposed for correction factor calculations in spreading resistance measurements on semiconductor device structures.
TL;DR: It is proposed that Sarcocystis orientalis Zaman and Colley (1975) be replaced by the name of Sarcocrystis singaporen8is, given to a parasite from Capra sibirica.
Abstract: Zaman and Colley (1975) described a sarcocys~ of Ra#us norvegicus which undergoes gametogony in the intestina] epithelial ce]ls of Python reticulatus. However, the name given for this parasite is now found to be occupied by a homonym, Sarcocystis orientalis, given to a parasite from Capra sibirica (Fam. Bovidae) from the region of U.S.S.R. and Mongolia (Machulskii and Miskaryan, 1958; Kalyakin and Zasukhin, 1975). I t is, therefore, proposed that Sarcocystis orientalis Zaman and Colley (1975) be replaced by the name of Sarcocystis singaporen8is.
TL;DR: A synthetic compound, 2a, 2b dihomo 15 (S) 15 methyl prostaglandin F2α methyl ester given 8 hourly by intramuscular injection was used to terminate pregnancies in 72 patients with a missed abortion, intrauterine fetal death, molar or anencephalic pregnancies.
TL;DR: It was concluded that sulphate conjugation of 4-hydroxy-3-methoxyphenylethanol predominates in most species of animals.
Abstract: The biosynthesis of the glucuronide and sulphate conjugates of 4-hydroxy-3-methoxyphenylethanol was demonstrated in vitro by using the high-speed supernatant and microsomal fractions of liver respectively. These two conjugates were also produced simultaneously by using the post-mitochondrial fraction of rat, rabbit or guinea-pig liver. In contrast only the glucuronide was synthesized by human liver and only the sulphate by mouse and cat livers. Neither of these conjugates was formed by the kidney or the small or large intestine of the rat. A high sulphate-conjugating activity was observed in mouse kidney; the rate of sulphation of 4-hydroxy-3-methoxyphenylethanol with kidney homogenate and high-speed supernatant preparations was 1.8 times greater than with liver preparations. The sulpho-conjugates of 4-hydroxy-3-methoxyphenylethanol and 4-hydroxy-3-methoxy-phenylglycol were also formed by enzyme preparations of rabbit adrenal and rat brain; the glycol was the better substrate in the latter system. Mouse brain did not possess any sulphotransferase activity. For the conjugation of 4-hydroxy-3-methoxyphenylethanol by rabbit liver, the Km for UDP-glucuronic acid was 0.22 mM and that for Na2SO4 was 3.45 mM. The sulphotransferase has a greater affinity for 4-hydroxy-3-methoxyphenyl-ethanol than has glucuronyltransferase, as indicated by their respective Km values of 0.036 and 1.3 mM. It was concluded that sulphate conjugation of 4-hydroxy-3-methoxyphenylethanol predominates in most species of animals.
TL;DR: A further case of hypothyroidism with recurrent episodes of ventricular tachycardia and ventricular fibrillation which was not associated with any of the established causes of this arrhythmia is reported.
Abstract: Ventricular tachycardia associated with myxoedema is rare. Only two cases have so far been documented. In the report by Hansen, the patient had recurrent chest pain which suggested coexisting coronary heart disease. In the second case, the patient developed recurrent ventricular tachycardia only after intravenous triiodothyronine was given. This paper reports a further case of hypothyroidism with recurrent episodes of ventricular tachycardia and ventricular fibrillation which was not associated with any of the established causes of this arrhythmia.
TL;DR: A simple colorimetric method for the determination of ammonia in water at the ppm level is described in this article, where Indophenol blue color is produced in an alkaline borate medium using phenol and hypo-chlorite as reagents.
Abstract: A simple colorimetric method is described for the determination of ammonia in water at the ppm level. Indophenol blue color is produced in an alkaline borate medium using phenol and hypo-chlorite as reagents. Comparison of color intensity is carried out by means of test tubes. When metal ions that interfere with ammonia determination are present in water, the interference can be prevented by applying a diffusion technique.
TL;DR: There were frequent elevations of serum glutamic-oxaloacetic transaminase, serum creatine phosphokinase and serum lactate dehydrogenase, indicating presence of damage to muscle fibres and the above enzyme elevations appeared short-lived except in the clinically most severe patient who developed acute tubular necrosis.
TL;DR: A brain tissue embolus was observed in a major pulmonary artery in the right lung, in a Neonate who died from intracranial haemorhage 36 hours after delivery, the fifth documented case in a neonate and the only one in whom survival had occurred beyond one hour.
Abstract: A brain tissue embolus was observed in a major pulmonary artery in the right lung, in a neonate who died from intracranial haemorhage 36 hours after delivery. This is the fifth documented case in a neonate and the only one in whom survival had occurred beyond one hour. Brain tissue emboli in the pulmonary circulation occur very rarely; it has been described in adults and children with head injuries. In newborn infants with severe congenital malformations of the central nervous system, brain tissue has been found growing in the lungs; the possibility of this being the result of prenatal brain trauma with embolization has been raised. In newborn infants, pulmonary brain tissue embolism as a result of birth trauma has been reported only very rarely; as far as the authors are aware, only four such cases have been documented. In view of the rarity of this condition, it was thought that the present case merited reporting.
TL;DR: A list of prerequisites, essential items of information and definitions applying to studies on induction of labour is presented and it is suggested that their use would permit proper analysis and comparison of results obtained by different investigators.
TL;DR: The development of Breinlia booliati is described in its natural host, Rattus sabanus and in an inbred strain of laboratory albino rat, where there was considerable growth in length of the female worms after this stage.
Abstract: The development of Breinlia booliati is described in its natural host, Rattus sabanus and in an inbred strain of laboratory albino rat. The growth of the parasite is similar in both the rat hosts. The third moult occurs between six-eight days and the final moult between 24-28 days. Larvae were recovered initially from the skin and carcass. After five weeks, developing stages were seen only in the thoracic and abdominal cavities, the site of development of the adult worms. Worms became sexually mature by 11-12 weeks and there was considerable growth in length of the female worms after this stage.
TL;DR: In this article, an exact solution to the problem of unsteady drawdown in a leaky artesian aquifer due to a constant discharge non-penetrating well is presented.
Abstract: Exact solution to the problem of unsteady drawdown in a leaky artesian aquifer due to a constant discharge nonpenetrating well is presented. Finiteness of the well radius and aquifer anisotropy are considered in formulating the problem. Solution is derived on the assumption that the flux entering the pumped well is uniformly distributed over the plane circular bottom of the well. The aquifer is considered to be finite in thickness, but of infinite lateral extent. The flow of ground water is assumed to be governed by Jacob's model of linear leakage. Laplace transformation technique is employed in the theoretical development. The drawdown function is numerically integrated in terms of dimensionless parameters of the flow system and the results are depicted in graphs.
TL;DR: In this article, it was shown that if a finite group G is soluble, then H is subnormal in G if and only if there exists an integer n such that for each g in G and a in S the commutator lies in H.
Abstract: Let H be a subgroup of a finite group G and let S be a set of generators of H . We prove that if G is soluble, then H is subnormal in G if and only if there exists an integer n such that for each g in G and a in S the commutator lies in H . This criterion for subnormality is also valid for soluble groups satisfying the maximal or the minimal condition on subgroups.
TL;DR: No significant relationship could be found between lasma oestriol and parity, maternal age, maternal height, maternal weight or fetal sex, but a significant but low correlation was found between birth weight and plasma oestRIol prior to labour and also ostriol increments from 30 weeks to delivery.
TL;DR: Breinlia booliati, a new filarial parasite of Rattus sabanus, has been successfully transmitted to 3 strains of laboratory rats by various routes of inoculation and may provide a useful experimental model for studying various aspects of filariasis.
TL;DR: An exact probability test for the comparison of cure-rate (or any other 2-category response variable) among three treatments is presented in detail and extension of the method to larger contingency tables is shown.
Abstract: An exact probability test for the comparison of cure-rate (or any other 2-category response variable) among three treatments is presented in detail; Extension of the method to larger contingency tables is also shown. It is suggested that the exact method should be used if the sample size for a particular investigation is small and/or when the chisquare test gives a probability level near borderline statistical significance.
TL;DR: In rapidly-changing and cosmopolitan Singapore, ergonomic principles are vital to all facets of manufacturing processes and the transportation and distribution of goods, but ergonomic practice can be complicated by several factors as indicated by such examples.
Abstract: Several examples of the need for the application of sound ergonomic principles in Singapore factories are presented. Emphasis is laid on the necessity to consider local habits and customs in the devising of ergonomic solutions to occupational health problems. Examples are given concerning vehicle cabin design, difficulties due to climate differences in applying personal protective equipment or in building design, inadequate displays warning dangers, and health consequences of technical improvements, safety measures, or measures to achieve greater efficiency. Sometimes ergonomic practices may promote productivity but be prejudicial to health. In rapidly-changing and cosmopolitan Singapore, ergonomic principles are vital to all facets of manufacturing processes and the transportation and distribution of goods, but ergonomic practice can be complicated by several factors as indicated by such examples. Language: en