Showing papers by "University of Glasgow published in 1977"
TL;DR: Light microscopic examination of the buffy coat zone of a microhaematocrit capillary tube expressed on to a slide was found to be consistently more reliable than other standard techniques in detecting trypanosomes in the circulation of cattle.
Abstract: Light microscopic examination of the buffy coat zone of a microhaematocrit capillary tube expressed on to a slide was found to be consistently more reliable than other standard techniques in detecting trypanosomes in the circulation of cattle. This method alaos allowed identification of different trypanosome species. Optimal results were obtained using darkground illumination.
666 citations
TL;DR: In this paper, the effect of stress state on the effective plastic strain to initiate ductile failure in three high strength steels is investigated, and failure initiation strains were correlated with a parameter which is a measure of the triaxiality of the stress state.
452 citations
TL;DR: The theory of nuclear electron capture is reviewed in the light of current understanding of weak interactions in this article, and experimental methods and results regarding capture probabilities, capture ratios, and EC/Beta(+) ratios are summarized.
Abstract: The theory of nuclear electron capture is reviewed in the light of current understanding of weak interactions. Experimental methods and results regarding capture probabilities, capture ratios, and EC/Beta(+) ratios are summarized. Radiative electron capture is discussed, including both theory and experiment. Atomic wave function overlap and electron exchange effects are covered, as are atomic transitions that accompany nuclear electron capture. Tables are provided to assist the reader in determining quantities of interest for specific cases.
304 citations
TL;DR: Nuclear and cytoplasmic viral RNAs synthesized in cells productively infected with herpes simplex virus type 1 at early and late times post-infection and in the presence of DNA and protein synthesis inhibitors suggest that synthesis of immediate early RNA within the nucleus may be restricted; alternatively, there may be rapid processing of primary transcripts.
271 citations
TL;DR: The maximum possible efficiency at which living systems are able to convert input nutrients to their own biomass is between 70 and 80 %.
Abstract: Summary
1. The maximum possible efficiency at which living systems are able to convert input nutrients to their own biomass is between 70 and 80 %.
2. Conversion efficiency in bacteria, protozoa and metazoan cells in culture approximates more closely to 60%.
3. Conversion efficiency during embryonic development begins below 60% and rises above this level in the later stages.
4. Very young, post-natal organisms have high net efficiencies; 50 to 70% in homeotherms and 50 to 80 % in poikilotherms.
5. In cellular systems, capable of proliferation, conversion efficiency is independent of food supply. This means that conversion is directly dependent on nutrient supply.
6. Control of growth at the tissue level may occur through the control of the supply of nutrients to the tissues and its entry into the cells.
7. Compensatory growth, after and during undernutrition, involves increased absorption efficiency and reduced metabolic costs.
220 citations
TL;DR: A model of textual comprehension is proposed based on the semantic distance effect and it is shown that the effect can be abolished under conditions where the two items appear in unrelated phrases.
213 citations
TL;DR: This work has shown that cell types growing in tissue culture form intercellular junctions which are permeable to nucleotides but not to RNA, DNA or protein.
213 citations
TL;DR: In this paper, Bate's 60th birthday is celebrated by P. G. Burke and B. L. Moiseiwitsch, who have published a book on the application of atomic processes and applications.
Abstract: Atomic Processes and Applications. (In Honour of David R. Bate's 60th Birthday.) Edited by P. G. Burke and B. L. Moiseiwitsch. Pp. x + 533. (North-Holland: Amsterdam, New York and Oxford, 1976.) Dfl.165; $65.95.
203 citations
TL;DR: The chapter discusses the way organisms work as energy transformers and the circumstances under which they transform energy and the reason they work in the way they do.
Abstract: Publisher Summary This chapter discusses physiological adaptation in the organism. Organisms are treated as machines, energy transformers that are designed to work in a certain way and at certain levels of efficiency under particular ecological conditions. The concept of design is central to biological explanation and within this framework, this chapter discusses two general issues: the design criteria used in the evolution of metabolic machines and the various metabolic strategies important in the operation of these machines. The chapter discusses the way organisms work as energy transformers and the circumstances under which they transform energy and the reason they work in the way they do. In the first instance, one is concerned with the operation of organisms in ecosystems and only in a subsidiary way with the operation of organisms as part of ecosystem metabolism. The latter is, of course, the more usual problem and discusses “ecological energetic.”
169 citations
TL;DR: The nuclear shell model has a very long history, during most of which as much effort has gone into the development of the formal and technical aspects of the model as into applying it to the description of nuclear properties.
Abstract: The nuclear shell model has a very long history, during most of which as much effort has gone into the development of the formal and technical aspects of the model as into applying it to the description of nuclear properties. This has been partly due to the formidable difficulties attendant on what would seem at the start to be an idiotic pursuit — the description of a complicated many-body system by means of a model lacking any theoretical justification and using a Hamiltonian about which nothing was known. It was also due in part to the utterly fascinating and beautiful mathematical structures that were devised in order to make the calculations possible at all. The earliest shell-model calculations, those of Feenberg and Wigner (FW 37), used methods based on group theory (supermultiplet theory). Racah (Rac 43, 49) further developed the algebra of angular momentum and the method of fractional parentage to the point where they became usable in atomic shell-model calculations. This work was taken up and extended to the case of protons and neutrons by H. A. Jahn and his collaborators (Jah 50, 51; JvW 51) and by Flowers (Flo 52). The problem tackled by them was that of ascribing sufficient approximate quantum numbers or labels to distinguish the different states arising from the filling of a shell and to produce tables of the corresponding coefficients of fractional parentage for use in calculating matrix elements.
166 citations
TL;DR: In this paper, a detailed study has been carried out on the propagation-mode characteristics of graded-index planar optical waveguides formed by silver-sodium ion exchange, and it has been found that the index profile can be accurately modeled by a monotonic decrease from a maximum value at the surface, following a second-order polynomial distribution.
Abstract: A detailed study has been carried out on the propagation-mode characteristics of graded-index planar optical waveguides formed by silver-sodium ion exchange. It has been found that the index profile can be accurately modeled by a monotonic decrease from a maximum value at the surface, following a second-order polynomial distribution. Definition of an effective diffusion constant leads to a universal mode-dispersion diagram applicable over a wide range of fabrication conditions. Interferometric observations of the refractive-index profile, together with electron microprobe analysis, give further support to the second-order polynomial distribution. The index profile has also been compared with silver-concentration profiles predicted by interdiffusion theory. Results obtained are also relevant to methods of coupling between planar and circular fiber-optical waveguides, where sections of optical fiber undergo ion exchange.
TL;DR: It is suggested that the larvae of N. dubius are immunosuppressive and that the efferent role of the immune response to T. muris is inhibited.
Abstract: Primary immune expulsion of Trichuris muris was markedly delayed by concurrent infection with Nematospiroides dubius. Maximum delay of expulsion was dependent on size and timing of N. dubius infection relative to T. muris infection. In NIH mice infection with 400 N. dubius larvae immediately before or after T. muris infection was found to be most effective in suppressing expulsion. Infection on day 8 of T. muris infection, when mice are sensitized to T. muris, also impaired expulsion. From this evidence it is suggested that the larvae of N. dubius are immunosuppressive and that the efferent role of the immune response to T. muris is inhibited. The results are discussed in terms of non-specific immunosuppression and their relevance to the tropical disease situation is emphasized.
TL;DR: It was demonstrated that the sulphydryl compounds β-mercaptoethylamine-HCl, cysteine and methionine significantly increased the survival rate of mice given a lethal dose of ethanol.
TL;DR: Recent theoretical work on the estimation of density functions provides reasons for differences in the application of commonly advocated discriminant or diagnostic methods and suggests which methods should provide greater realism.
Abstract: Important clinical differences arising in the application of commonly advocated
discriminant or diagnostic methods demand a thorough assessment of the realism of
their different assessments. Recent theoretical work on the estimation of density
functions provides reasons for these differences and suggests which methods should
provide greater realism. These suggestions are strongly supported by a simulation
study. Specific recommendations are made concerning statistical diagnostic practice.
TL;DR: The data indicate that htyroid dysfunction, in particular hypothyroidism, is common in adults with Down's syndrome, though specific tests are usually required to make the diagnosis.
Abstract: The thyroid status of 82 institutionalized adults with Down's syndrome has been assessed. Compared to age and sex matched control subjects, these patients had significantly lower mean total serum thyroxine (T4) and triiodothyronine (T3) concentrations (T4; 69.1+/-22.2 nmol/1; (mean+/-SD) vs. 100.1+/-19.1, P less than 0.001; T13; 1.61+/-0.47 nmol/1 vs. 1.76+/-0.34, P less than 0.025), lower free thyroxine index (FTI), (FTI; 66.1+/-22.4 vs. 95.1+/-20.2, P less than 0.001), and higher basal serum thyrotrophin (TSH) concentrations (TSH; 7.6+/-10.7 mU/1 vs. 3.8+/-1.5, P less than 0.001). These changes were not related to age or sex. Abnormalities in one or more test of thyroid function were demonstrated in at least 38 (46%) of the 82 patients. Two main patterns of abnormality were defined: 1) subnormal T4, FTI and elevated basal TSH levels (primary hypothyroidism) in 13 (16%). All seven of the 13 patients in whom TRH tests were performed showed the expected exaggerated TSH response, and seven out of the 13 patients (54%) had positive thyroid antibodies, 2) Subnormal T4, subnormal or low normal FTI, and basal TSH levels within the normal range in 18 (22%). The mean basal TSH concentration was, however, significantly higher than in patients with normal T4 and FTI levels, suggesting a minor degree of thyroid failure. Only two of the 18 patients (11%) had positive thyroid antibodies. Of the 17 patients in the group tested, 13 showed a normal TSH response to TRH, three an exagerrated response (all females), and one had an impaired response. Other patterns of abnormal thyroid function were observed occasionally: one female patient had biochemical T3 toxicosis; another had the biochemical pattern of subclinical hypothyroidism, four patients with normal basal T4, FTI and TSH levels showed an exaggerated TSH response to TRH and one patient had an impaired response. These data indicate that htyroid dysfunction, in particular hypothyroidism, is common in adults with Down's syndrome, though specific tests are usually required to make the diagnosis. The general reduction in thyroid function in Down's syndrome may be due to impaired development of the thyroid gland. However, frank chemical hypothyroidism may occur only when thyroiditis is superimposed on preexisting diminished thyroid reserve.
TL;DR: Methods for predicting peptide chain conformation have been applied to amino acid sequences adjacant to the carbohydrate attachment sites of glycoproteins containing the N -glycosylamine type of protein-carbohydrate linkage.
TL;DR: The growth and development of plants of Sargassum muticum (Yendo) Fensholt is described both from culture and from plants growing in the sea at Friday Harbor, San Juan Island, Washington, U.S.A.
TL;DR: Work with laboratory animals indicates a mechanism which is the antithesis of the overstimulation concept: that quantities of antigen sufficiently large to activate IgE immunoregulatory mechanisms, particularly suppressor T cells, are normally absorbed across the mucosae and that, where other conditions for the activation of these cells are appropriate, inhibition rather than stimulation of IgE responses results.
TL;DR: In this article, a subambient thermal volatilization analysis (TVA) technique is described, where degradation products initially at −196°C are allowed to warm up to ambient temperature in a controlled manner under vacuum conditions.
Abstract: In the subambient thermal volatilization analysis (TVA) technique, degradation products initially at −196°C are allowed to warm up to ambient temperature in a controlled manner under vacuum conditions, and volatilization from the sample tube to a trap at −196°C is monitored by means of a Pirani gauge. The technique is discussed in relation to earlier TVA work in which volatilization from a heated polymer sample was followed. Design and operation of a subambient TVA system are described, and examples of the application of the technique to the study of the degradation products of seven polymers are considered.
TL;DR: The reduction in activity of coproporphyrinogen oxidase in the haem biosynthetic pathway and the elevation of delta-aminolaevulinic acid synthase inThe peripheral blood appear to be diagnostic of hereditary coproporphyria whether in attack, remission, or in the latent form.
Abstract: Hereditary coproporphyria is biochemically distinct from the other porphyrias and is characterized by excessive excretion of coproporphyrin in faeces and usually in urine. The laboratory findings in 28 patients with this disease are presented and the clinical details of eight patients who have been in attack summarised. The remaining 20 patients were latent for the disease. In all patients studied the activity of delta-aminolaevulinic acid synthase was raised and coproporphyrinogen oxidase depressed in the leucocyte. This indicates the partial enzyme block in the haem biosynthetic pathway in this disease. The activities of the other enzymes in the pathway, leucocyte ferrochelatase and erythrocyte delta-aminolaevulinic acid dehydratase, porphobilinogen deaminase and uroporphyrinogen decarboxylase showed no consistent change. On review of 111 cases, 35 per cent presented in acute attack: 80 per cent had abdominal pain, 34 per cent vomiting, 29 per cent solar sensitivity, 23 per cent neurological involvement, 23 per cent psychiatric symptoms and 20 per cent severe constipation. Only two fatalities have been published, both from respiratory failure. There was a female preponderance of cases in attack of 2-5:1 and in the latent cases of 1-5:1 suggesting hormonal provocation in the uncovering of the disease. Drugs were implicated as precipitating 54 per cent of acute attacks and in 34 per cent of cases, these were barbiturates. This study demonstrates the reduction in activity of coproporphyrinogen oxidase in the haem biosynthetic pathway and the elevation of delta-aminolaevulinic acid synthase in the peripheral blood. These features, together with the typical abnormal porphyrin excretion pattern, appear to be diagnostic of hereditary coproporphyria whether in attack, remission, or in the latent form.
TL;DR: Calculations based on the mortality of whooping-cough before 1957 predict accurately the subsequent decline and the present low mortality, which is questionable, at least in the U.K.
TL;DR: Examination of several stools from the same patient showed that in this age group the viral flora of the gut changes rapidly and that the viruses seen by electron microscopy were only rarely grown in cell culture and vice versa.
Abstract: Stools from 183 babies under 2 years of age admitted to Ruchill Hospital with diarrhoea were examined by electron microscopy, virus culture, bacterial culture and light microscopy. As far as possible, several stools were examined from each patient and the results showed rotaviruses, astroviruses and other viruses in association with symptoms, as well as the expected bacterial pathogens. Examination of several stools from the same patient also showed that in this age group the viral flora of the gut changes rapidly and that the viruses seen by electron microscopy were only rarely grown in cell culture and vice versa. This phenomenon was particularly noted with adenoviruses. In 30% of cases no microbial pathogen was identified and in the remainder the presence of the infecting organism did not always coincide with the symptoms. It is concluded that, with viruses at least, presence of the organism does not constitute proof of causation.
TL;DR: It is shown that worm expulsion and impaired reproduction may represent independent aspects of the immune response to T. spiralis and it is suggested that MLNC do not cause worm expulsion directly, but cooperate with another component of the host's defence mechanism.
Abstract: Cells capable of transferring immunity to Trichinella spiralis, i.e. of accelerating adult worm expulsion, were present in the mesenteric lymph nodes of mice infected for 4, 6 or 8 days, but not in mice infected for only 2 days. The time-course of worm expulsion in mice infected on the day of transfer was similar in recipients of day 4 or day 8 cells, expulsion becoming marked only when the recipients had been infected for at least 6 days. Transfer of cells 4 or 6 days after infection did not result in an accelerated worm expulsion; transfer 1 or 2 weeks before infection did not enhance the level of immunity in recipient mice. In contrast to the results obtained with mesenteric lymph node cells (MLNC) on immunity was transferred when recipients were given spleen cells taken from donors infected for 8 days. It is suggested that MLNC do not cause worm expulsion directly, but cooperate with another component of the host's defence mechanism. Accelerated expulsion in recipients of cells was accompanied by a premature decline in fecundity of female worms. Evidence is presented to show that worm expulsion and impaired reproduction may represent independent aspects of the immune response to T. spiralis.
TL;DR: The finding that inbred NIH and BALB/c mice acquire resistance to N. dubius offers possibilites for the systematic analysis of lymphoid cell activity in initiating and expressing immunity to this parasite.
Abstract: The development of immunity to Nematospiroides dubius was studied in three strains of inbred mice (BALB/c, C3H and NIH). Although a primary infection in NIH mice persisted for two months without evidence of a reduction in worm numbers, female mice of this strain readily developed resistance to reinfection. The degree of resistance was enhanced when an immunizing infection of 600 larvae was administered as 6 separate doses of 100 larvae given between days 0 and 11, and the worms removed by anthelmintic treatment given on days 15, 21, 28 and 35. Immunity in mice immunized in this way was manifest both as a reduction in worm recoveries on days 9–14 after challenge and also as an expulsion of established worms from the intestine. BALB/c mice were initially less resistant, but expelled most of the worms which became established; C3H mice showed no evidence of expulsion. The finding that inbred NIH and BALB/c mice acquire resistance to N. dubius offers possibilities for the systematic analysis of lymphoid cell activity in initiating and expressing immunity to this parasite.
TL;DR: The effects of three inhibitory stimuli, sympathetic nerve stimulation, noradrenaline (NA) and isoprenaline have been examined on three forms of motor activity in the rabbit colon, the response to pelvic (parasympathetic) nerve stimulating, acetylcholine (ACh) and spontaneous tone.
Abstract: 1. The effects of three inhibitory stimuli, sympathetic nerve stimulation, noradrenaline (NA) and isoprenaline have been examined on three forms of motor activity in the rabbit colon, the response to pelvic (parasympathetic) nerve stimulation, acetylcholine (ACh) and spontaneous tone.2. The response to pelvic nerve stimulation is most effectively inhibited by sympathetic nerve stimulation, much less effectively by NA and hardly at all by isoprenaline. The sympathetic nerves can inhibit the pelvic response at frequencies of stimulation which do not affect spontaneous tone. The inhibitory effect of sympathetic stimulation, and of NA, on the pelvic response is reduced by phentolamine 5 x 10(-6)M and unaffected by propranolol 5 x 10(-6)M suggesting the effect is mediated via alpha receptors.3. The response to ACh is inhibited by all three stimuli equally. The inhibitory effect of sympathetic nerve stimulation and of isoprenaline is reduced by propranolol 5 x 10(-6)M. The inhibitory effect of NA is also reduced by propranolol but to a lesser extent. Phentolamine 5 x 10(-6)M has a small effect in reducing the inhibitory effect of sympathetic nerve stimulation or of NA. This effect of phentolamine is lost if the participation of motor nerves in the response to ACh is excluded by either tetrodotoxin 10(-7) g/ml. or cold storage for 10-14 days. These results suggest that inhibition of the ACh response takes place mainly at the muscle by activation of beta receptors but that ACh may have a small indirect stimulant action through motor nerves and this is susceptible to inhibition through alpha receptors.4. All three stimuli are equally effective in lowering smooth muscle tone. This inhibitory effect of sympathetic nerve stimulation and of isoprenaline is reduced by propranolol 5 x 10(-6)M and unaffected by phentolamine 5 x 10(-6)M. The inhibitory effect of NA is reduced by propranolol but again is less sensitive to block than the other two inhibitory stimuli. Phentolamine is without effect on the inhibitory action of NA and the combination of phentolamine with propranolol is no more effective than propranolol alone. These results suggest that NA liberated by sympathetic nerves and isoprenaline inhibit myogenic tone in the smooth muscle by an action on beta receptors but the action of NA added to the bath cannot be fully explained in this way.
TL;DR: Water-lead concentrations in the maternal home during pregnancy correlated with blood-lead concentration in the mentally retarded children, reinforcing the probable association between lead exposure during pregnancy and the development of mental retardation of otherwise unknown aetiology.
TL;DR: It is shown that the construction yields all possible difference sets with parameters (36, 15, 6, 9, 9) in an abelian group of order 36.
TL;DR: In this paper, the authors discuss the continuation of asymptotically free quark model predictions for e+e− → hadrons in the complex q2 plane from spacelike to near timelike regions.
TL;DR: It is postulated thatΒ2-microglobulin could be necessary for the expression and possible synthesis of the HLA antigen in the Daudi cell.
Abstract: The Daudi cell line, established from a Burkitt lymphoma, has recently been found to be HLA- andΒ2-microglobulin-negative, although it expresses B lymphocyte alloantigens. This report is concerned with the reexpression of HLA-A10, B38, and B17 on the Daudi cell, after cell fusion with another human cell line (Raji) or with mouse fibroblasts. In the latter fusion, the same HLA specificities are re-expressed, but not humanΒ2-microglobulin while mouseΒ2-microglobulin andH-2 could be detected. No such reexpression was observed when Daudi was fused with the F9 mouse teratocarcinoma, which lacks mouseΒ2-m andH-2. No HLA activity (alloantigenic and xenogenic activity) was detected in the membrane or cytoplasm of Daudi, using salt extraction and sonication. Therefore we postulate thatΒ2-microglobulin could be necessary for the expression and possible synthesis of the HLA antigen.