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Showing papers by "University of Manchester published in 1968"


Journal ArticleDOI
TL;DR: In this article, it is suggested that, when it is desired to discriminate between rival hypotheses, or to determine the exact variation between components, weight per-cent comparisons be discontinued (wherever possible) in favour of molar ratio comparisons in which one of the components (the divisor) is a constant.
Abstract: Harker diagrams and other ternary weight per-cent diagrams distort genetic trends by changing their slopes. They can not be readily used to discriminate between rival hypotheses. Two theorems have been proven which show the desirability of using certain types of ratios, instead of per-cent values, for comparisons. It is suggested that, when it is desired to discriminate between rival hypotheses, or to determine the exact variation between components, weight per-cent comparisons be discontinued (wherever possible) in favour of molar ratio comparisons in which one of the components (the divisor) is a constant. Variation diagrams of this type offer reliable discrimination between rival hypotheses, and yield the true relationship between variables in every case. An example involving crystal fractionation of olivine and pyroxene from a basic sill is developed in detail, and other potential uses are mentioned. This technique is completely general and is not restricted to chemical components, or to any scale of system, or to any field of study, providing certain essential conditions are fulfilled.

272 citations


Journal ArticleDOI
26 Oct 1968-Nature
TL;DR: The work described here was designed to test the hypothesis that the species in such a grazing succession make use of different levels of the herb layer and might therefore be expected to take different proportions of the plant parts available.
Abstract: ECOLOGICAL separation of the African grazing ungulates has been found to be difficult1, although some authors have observed that these ungulates often take part in grazing successions in which species follow each other in characteristic sequences during their seasonal movements2. The migratory populations of the Serengeti take part in such a succession; first zebra (Equus burchelli), second wildebeest (Connochaetes taurinus albojubatus) and lastly Thomson's gazelle (Gazella thomsoni). The semi-migratory topi (Damaliscus korrigum) tends to associate with zebra. The work described here was designed to test the hypothesis that the species in such a grazing succession make use of different levels of the herb layer and might therefore be expected to take different proportions of the plant parts available.

251 citations


Journal ArticleDOI
TL;DR: It is suggested that there are two distinct modes of dissociative recombination, which are called direct and indirect, and it is shown that spectroscopic data can be used to give estimates of these rates.
Abstract: It is suggested that there are two distinct modes of dissociative recombination, which are called direct and indirect. The direct mechanism, first described by Bates, involves a single radiationless transition, whereas the indirect mode occurs through an intermediate Rydberg state of the molecule. The recombination rate for ground-state ions should decrease with increasing temperature for both processes, but the rate of decrease is faster for the indirect process. Complete calculations of the recombination rate do not seem possible yet, but it is shown that spectroscopic data can be used to give estimates of these rates. The method is illustrated by a partial calculation of the rate of direct recombination in nitric oxide.

246 citations


Journal ArticleDOI
TL;DR: In this paper, the authors surveyed nine relatively new exporters with a view to defining their motivation and characteristics in relation to their first export orders and found that the characteristics of these innovators/initiators of exporting are similar to those of innovators in other situations.
Abstract: Surveys nine relatively new exporters with a view to defining their motivation and characteristics in relation to their first export orders. Suggests that the characteristics of these innovators/initiators of exporting are similar to those of innovators in other situations. Reveals that those who are likely to start exporting are those who have little loyalty to the UK marketing area. Underlines the importance of change agents in initiating the innovation.

221 citations


Journal ArticleDOI
TL;DR: In this paper, the development of speech audiometry was discussed. But this work focused on speech audiology, and not on audiology in general speech, rather than audiology specifically.
Abstract: (1968) Developments in Speech Audiometry British Journal of Audiology: Vol 2, No 1, pp 3-10

191 citations


Journal ArticleDOI
TL;DR: In this article, it was shown that the Schottky barrier height depends on the particular method of surface preparation, and subsequently shows a slow change with time, reaching a steady value over a period of days or even weeks.
Abstract: Measurements have been made of the height of Schottky barriers obtained by evaporating metal films on to n-type silicon. In the case of surfaces prepared by chemical methods, the height of the barrier initially depends on the particular method of surface preparation, and subsequently shows a slow change with time, reaching a steady value over a period of days or even weeks. This final value is independent of the method of surface preparation, but depends on the choice of metal. For junctions made by evaporation on to silicon cleaved in an ultra-high vacuum, the barrier height shows no ageing and is substantially independent of the metal. These observations can be explained in terms of the existence of a thin oxide layer on the chemically prepared surfaces, together with the assumption that the density of surface states is about two orders of magnitude lower on the chemically prepared surfaces than on the cleaved surfaces.

162 citations


Journal ArticleDOI
TL;DR: Low-frequency electric currents of a few milliamperes flowing through the body cause muscular contractions, which may make a subject unable to let go of a live conductor, leading to asphyxia, unconsciousness, and even death.
Abstract: Low-frequency electric currents of a few milliamperes flowing through the body cause muscular contractions. In the arm such an effect may make a subject unable to let go of a live conductor. The highest currents which 99.5 per cent of men and 99.5 percent of women are able to let go have been shown to be 9 and 6 mA, respectively. Currents somewhat larger than this, in the range of 20 to 40 mA, passing across the chest may arrest respiration leading to asphyxia, unconsciousness, and even death.

160 citations


Journal ArticleDOI
TL;DR: In this paper, it is shown that the full specification of an assembly of long flexible molecules, needed for a statistical-mechanical study, requires an infinite set of topological invariants, and the first two of these are derived in detail.
Abstract: It is shown that the full specification of an assembly of long flexible molecules, needed for a statistical-mechanical study, requires an infinite set of topological invariants, and the first two of these are derived in detail. It is argued that these invariants provide a better description of the topology of the system than a more intuitively obvious one, for example, to state the condition that a molecule contains a single knot is very complicated requiring an infinite number of invariants, just as the specification of a function at a point requires an infinite number of Fourier coefficients. It is shown that the probability of molecules taking up configurations with given values for the invariants is a problem in quantum field theory, and that for example the first invariant leads to a formalism isomorphic with the electrodynamics of scalar bosons, and the governing differential equations for one and two molecules are derived. The transition from a real polymer to its representation by a continuous curve leads to divergences, but these can be absorbed by renormalizing the step length and entropy per monomer; within these two changes the topological properties are independent of monomer structure.

143 citations


Journal ArticleDOI
TL;DR: In this article, it was shown that quantization of a digital filter's coefficients in an actual realization can be represented by a "stray" transfer function in parallel with the corresponding ideal filter.
Abstract: The frequency response of a digital filter realized by a finite word-length machine deviates from that which would have been obtained with an infinite word-length machine. An "ideal" or "errorless" filter is defined as a realization of the required pulse transfer function by an infinite word-length machine. This paper shows that quantization of a digital filter's coefficients in an actual realization can be represented by a "stray" transfer function in parallel with the corresponding ideal filter. Also, by making certain statistical assumptions, the statistically expected mean-square difference between the real frequency responses of the actual and ideal filters can be readily evaluated by one short computer program for all widths of quantization. Furthermore, the same computations may be used to evaluate the rms value of output noise due to data quantization and multiplicative rounding errors. Experimental measurements verify the analysis in a practical case. The application of the results to the design of the digital filters is also considered.

114 citations



Journal ArticleDOI
TL;DR: In this article, an idealization of the lower boundary of the primary deformation zone in orthogonal cutting is proposed, which is made up of a length L extending from the tool tip in the direction of cutting and a length from the extremity of L (remote from tool tip) at an angle of 45° until it intersects the free surface of the workpiece.

Journal ArticleDOI
01 Aug 1968-Tellus A
TL;DR: In this paper, a simple model is developed to investigate some of the features of the surface boundary layer of a hurricane, where the flow above the friction layer is represented by a steady cylindrical vortex in which there is gradient flow, specified by suitably choosing the radial pressure profile.
Abstract: A simple model is developed to investigate some of the features of the surface boundary layer of a hurricane. The flow above the friction layer is represented by a steady cylindrical vortex in which there is gradient flow, specified by suitably choosing the radial pressure profile. It is assumed that the flow in the main vortex is approximately geostrophic at large distances from the centre and the Ekman solution is taken as appropriate for the boundary layer flow at these distances. A momentum integral method is used to follow the boundary layer development to the centre regions of the vortex. Radial profiles of boundary layer thickness and induced vertical veolocity are obtained when a constant eddy viscosity, K M , is taken as characteristic of the turbulence in the friction layer. Two surface boundary conditions are examined; the no-slip condition and the condition that the surface stress be in the direction of the surface wind. The former of these is found to be the more satisfactory and gives qualitative agreement with observations. The effects of radial and vertical variations of K M are discussed in relation to the surface condition but an inadequate knowledge of the turbulent structure prevents a more realistic formulation of the layer at this stage. DOI: 10.1111/j.2153-3490.1968.tb00388.x

Journal ArticleDOI
TL;DR: In this paper, a general expression for the angular distribution of electrons scattered resonantly by molecules is given for particular types of molecules, and angular distribution coefficients are tabulated for these types.
Abstract: A general expression has been obtained for the angular distributions of electrons scattered resonantly by molecules. Specific expressions are given for particular types of molecules, and angular distribution coefficients are tabulated for these types.

Journal ArticleDOI


Journal ArticleDOI
TL;DR: Methods of generating the coding and decoding patterns, derived from the simple mathematical formulation of the multiplexing technique, are described.
Abstract: A multiplex technique is described that is binary in nature and that can be used in the observation of a dispersed spectrum in any wavelength region for which a detector exists. The subsequent data processing involves the minimum possible number of operations and can easily be carried out in real time. The number of observations that must be made is also a minimum, equal to the number of spectral elements. Methods of generating the coding and decoding patterns, derived from the simple mathematical formulation of the multiplexing technique, are described.

Journal ArticleDOI
TL;DR: The results were taken to imply that, under these conditions, the spontaneous movements of both Na(+) and K(+) across the cell membrane, down their respective concentration gradients, served to concentrate the glycine in the tumour cells (Christensen's hypothesis).
Abstract: 1. Tumour cells were starved to deplete them of ATP and transferred to 0.9mm-glycine in Ringer solutions containing 2mm-sodium cyanide and various Na(+) and K(+) concentrations. The uptake of glycine then usually reached a peak by about 10min. 2. When cellular [Na(+)] and extracellular [Na(+)] were each about 30m-equiv./l., the maximum amount of glycine absorbed increased between 1.2- and 3.0-fold on lowering extracellular [K(+)] from 128 to 10m-equiv./l. 3. When extracellular [Na(+)] was 150m-equiv./l., the ratio, R, of the cellular to extracellular glycine concentrations increased progressively, from near 1 to about 9, when cellular [Na(+)] was lowered from 120 to 40m-equiv./l. 4. When cellular [Na(+)] was almost constant, either at 45 or 70m-equiv./l., R fell about 14-fold when extracellular [Na(+)] varied from 150 to 16m-equiv./l. 5. Values of R near 0.2 were found when cellular [Na(+)] was about four times as large as extracellular [Na(+)]. 6. R fell about threefold when the cells were put with 12mm- instead of 0.9mm-glycine. 7. The results were taken to imply that, under these conditions, the spontaneous movements of both Na(+) and K(+) across the cell membrane, down their respective concentration gradients, served to concentrate the glycine in the tumour cells (Christensen's hypothesis).

Journal ArticleDOI
TL;DR: The Chalcidoidea are very numerous in species, well over 2000 being described from the nearctic region and in the British Isles alone there are at least 1000 species, and most of the species have very wide distribution areas, which may be said almost certainly even about the lesser-known species.
Abstract: Among sexually reproducing organisms, speciation involves the division of a species by the appearance of reproductive barriers which isolate a part of its population. Such barriers prevent, or at least greatly retard, the exchange of genetic material between the separated populations so that they are able to diverge genetically under the influences of natural selection, or genetic drift in small populations. If one accepts the argument of most evolutionists that the reproductive barriers operating in animal speciation must be of a geographical nature (e.g. Mayr, 1963), and that speciation must always be allopatric, then one is confronted with something of a paradox by a group of parasitic wasps, the Chalcidoidea. Chalcids are very numerous in species, well over 2000 being described from the nearctic region (Peck, 1963) and in the British Isles alone there are at least 1000 species. The superfamily is probably in a state of active evolution at the present time, a fact suggested by several assemblages of closely allied or sibling species occurring in most families. However, many species, including groups of sibling species, extend over large geographical areas. Boucek (1965) writes \"... the Chalcidoidea are poor subjects for zoogeographic conclusions. Most of the species have very wide distribution areas, which may be said almost certainly even about the lesser-known species.\" Associated with this wide geographical distribution of chalcids is a ready dispersal of adults into many different habitats within the range of the species. They may be found in habitats far from the nearest host; examples are certain Mesopalobus, Torymus and Olynx species parasitic in oak galls but sometimes found on sand-dunes or moorland, miles from the nearest oak tree. No doubt adult dispersal is an adaptation to meet the situation of a scattered host distribution, and its efficacy is shown by the parasitization of small, isolated host populations. Being small insects, usually only 2 or 3 mm long, chalcids can be readily carried in air currents. Accidental transportation by man must also occur frequently. As a consequence of ready dispersion, both across geographical obstacles and into a variety of habitats, prolonged geographical isolation of populations is probably less frequent than in most other groups of animals. How can this be reconciled with the apparently rapid evolutionary rate in the Chalcidoidea? A possible answer to this question has emerged

Journal ArticleDOI
01 Dec 1968
TL;DR: In this article, an analytical and experimental study of the additional losses which occur in induction motors supplied with nonsinusoidal waveforms is presented, and the manner in which the losses are related to the machine design and the supply harmonic content is described.
Abstract: The paper presents an analytical and experimental study of the additional losses which occur in induction motors supplied with nonsinusoidal waveforms. Measurements on an inverted induction motor are used to show the importance of losses due to skew-leakage and end-leakage fluxes, and to verify the methods developed for calculating these components. Computed losses are compared with test results obtained on a variety of machines and supply waveforms, and the agreement is shown to be consistently good. The manner in which the losses are related to the machine design and to the supply harmonic content is described.

Journal ArticleDOI
TL;DR: It is likely, therefore, that the snails are extremely localized in their wanderings, the more so as the authors had to collect from each division, take the samples away to be marked, and scatter them on release, each at random in its own division.
Abstract: On the discovery of area effects in morph frequency variation in the snail Cepaea nemoralis on the Marlborough Downs (Cain & Currey 1963 a) an intensive study with mark-release-recapture methods of a population subject to these effects was begun. The area investigated was divided into four quarters (downland grass) and two nettlepatches; the snail population is continuous through the area. Frequent visits were made during the snails' active season in 1962, 1963 and 1964; in 1965 and 1966 a single large sample was collected, marked and released in the spring. Five-banded shells are absent. The scoring of mid-bandeds with reduced bands being difficult, attention was concentrated on the principal colour morphs, yellow, pink and brown. Thrushes were predating the snails heavily in 1962, but the hard winter of 1962/3 removed them, and they have not yet returned in any numbers; the snail population does not seem to have been affected by this hard season. Throughout the period of investigation, the density of snails in the nettlepatches has been about ten times that in quarters 2, 3 and 4. Quarter 1 has less than half the density in the other quarters, and differs markedly from them and the nettlepatches in morph frequency, although it resembles quarter 2 strongly in vegetation. It is likely, therefore, that the snails are extremely localized in their wanderings, the more so as we had to collect from each division, take the samples away to be marked, and scatter them on release, each at random in its own division. Our estimates of migration from one division to another also suggest strong localization and perhaps homing. The total population in the area is about 3000 adults. Subpopulations have decreased in all divisions from 1963 to 1965. Adult survival rates are high, about 0.65 per year; no differential survival of the colour classes has been found, but much more data are needed. Predation by thrushes in 1962 was heavy in the summer, but not in proportion to snail density; the nettlepatches were proportionately much less predated, probably because of their dense growth of herbage. Winter predation, by contrast, was almost entirely in the nettlepatches, then showing expanses of bare earth. A check on our own efficiency of collecting shows that we are taking non-random samples in the quarters (downland grass) but not in the nettlepatches. We find pinks rather more conspicuous than yellows, but dark browns much less conspicuous than either. As the snails' bodies in this area are very dark, yellows appear green, pinks dirty straw-colour. It seems unlikely that browns are really more cryptic visually than yellows. Possibly their behaviour is different. The samples of predated shells taken by the thrushes agree very closely with our samples, and it appears that they also are predating with a bias (missing browns) in the quarters but not in the nettlepatches. Morph frequencies show no sign of alteration in the period of investigation, except that in 1963 and 1964 there was a drop in percentages of browns in quarters 2, 3 and 4, apparently not continuing in 1965 and 1966. (The compensatory increase is shared equally between pinks and yellows.) This could well be due to the sudden cessation of selection by thrushes, but the rate seems excessive if there was selection only on adults. There is no obvious relation between morph frequencies and population density. The growth in size of the juveniles in our samples has been studied through the snails' active season. It is clear that they take two years to reach maturity (i.e. to form the lip terminating the adult shell). This finding and the survival rates give a minimum generation interval of four years, and the actual period may be close to five in this area.


Journal ArticleDOI
23 Apr 1968
TL;DR: In this article, an exciton resonance state originating from the Ba state of the pyrene molecule was determined as a function of the intermolecular separationr (A) function.
Abstract: are determined as functions of the intermolecular separationr (A). V' is shown to be consistent with an exciton resonance state originating from the 'Ba state of the pyrene molecule.

Journal ArticleDOI
TL;DR: In this article, a model is constructed of a spherically symmetric self-gravitating condensation of neutral hydrogen immersed in an Hii region, where the structure of the condensation is represented by the isothermal gas sphere at a temperature of 100°K.
Abstract: A model is constructed of a spherically symmetric self-gravitating condensation of neutral hydrogen immersed in anHii region. The structure of the condensation is represented by the isothermal gas sphere at a temperature of 100°K. Typical parameters of such a condensation compatible with the estimated ultra-violet radiation field in the central regions of the Orion Nebula are, mass ≈1M ⊙; radius ≈1016 cm; mean density ≈10−15 gm cm−3. The condensations are not static configurations but evolve because of mass loss by ionization from their surfaces. Perhaps 5% become gravitationally unstable and collapse. The remainder act as sources of ionized gas which flows into the surrounding nebula.

Journal ArticleDOI
01 Jan 1968-Nature
TL;DR: In this article, the authors reported the successful detection of linear polarization in all of the four known sources, including the pulsating stars, in the wide frequency band over which intense radiation is emitted simultaneously.
Abstract: The mechanism of emission from the pulsating radio sources reported by Hewish et al.1 seems to be quite different from that of any other celestial radio source, particularly because of the wide frequency band over which intense radiation is emitted simultaneously2. An analogy may be found, however, in the radio pulse emitted by a cosmic ray shower3,4, in which a sheet of particles moving relativistically may emit linearly polarized radiation when they are deflected by the Earth’s magnetic field. It seemed appropriate therefore to search for linear polarization in the pulsating stars, and we here report the successful detection of linear polarization in all of the four known sources.

Journal ArticleDOI
TL;DR: In this paper, the authors argue that much of the criticism of the use of the equilibrium model by social anthropologists is due to a misunderstanding arising because though all social life exists in time, and all processes in time involve changes, we have to define several different kinds of time as well as distinctive types of change.
Abstract: There has been considerable criticism of the use of the equilibrium model by social anthropologists. The argument of this paper is that much of this criticism is due to a misunderstanding arising because though all social life exists in time, and all processes in time involve changes, we have to define several different kinds of “time” as well as distinctive types of “change.” It is contended that each type of social institution, or cultural pattern, has a particular kind of time scale in its very structure. Thus the structure of a family system can only be analyzed in four generations, and in subsistence systems perhaps only in five to six generations. Other institutions have other built-in time scales. It is proposed to call the time scale of an institution its structural duration. One important way of studying an institution is to analyze its structural duration. In an analysis of this kind, the emphasis is on the manner in which the institution would operate through time if internal contradictions or external intruding events did not interfere with its passage through its structural duration. Therefore an analysis of the structural duration of an institution is necessarily in an equilibrium model. Many studies have taken this form, but have been misread as if they were dealing with what happened in actual historical time. It is argued that since changes are of several kinds in a suggested range, from repetitive or recurrent changes of personnel through limited structural changes to radical structural changes, it is possible to assess what kinds of changes are occurring only by examining them within the structural durations of institutions, held steady as a first step in analysis as if in actual equilibrium. But this provides only a heuristic scheme in which to handle the observations; it is not a theory giving us a set of interdependent propositions. More and more actual changes may be fed in as the analysis tries to cope with greater ranges of reality. The argument is illustrated with examples from studies of several social spheres. There is also a discussion of how the method enables the analyst to analyze observations collected over a limited period of time in terms of a much longer period in order to assess the types of change that are occurring.

Journal ArticleDOI
06 Jan 1968-Nature
TL;DR: In this paper, it is shown that the normal stress differences P11−p22 and p22−p33 are determined by the values of pressure, −p22, on the stationary and rotating walls of cone and plate (cp), plate and plate(pp) and concentric cylinder (cc) apparatuses.
Abstract: IT is well known1 that, in suitable flow conditions, the normal stress differences P11−p22 and p22−p33 are determined by the values of pressure, −p22, on the stationary and rotating walls of cone and plate (cp), plate and plate (pp) and concentric cylinder (cc) apparatuses. The common use of small holes (filled with static liquid) for measuring these pressures must give rise to a systematic error, pH say, where is the pressure recorded using a hole and −p22 is the pressure which would act on the wall if the hole were absent.

Journal ArticleDOI
01 Jan 1968-Nature
TL;DR: In this paper, the three other sources reported by Hewish et al. 1 have been studied with the 250 ft. telescope at Jodrell Bank at frequencies of 151 MHz, 408 MHz and 922 or 1,412 MHz, to obtain the spectrum of the radio emission and compare the shapes of the pulses emitted by the four known sources.
Abstract: Following the observations1,2 of the pulsating radio source CP 1919 at α = 19h19m, δ = 21° 47′, the three other sources reported by Hewish et al. 1 have been studied with the 250 ft. telescope at Jodrell Bank. Simultaneous observations have been made on frequencies of 151 MHz, 408 MHz and 922 or 1,412 MHz, to obtain the spectrum of the radio emission and to compare the shapes of the pulses emitted by the four known sources.

Journal ArticleDOI
TL;DR: Murray’s finding that the hyalozonate gene when homozygous pales shell colour as well as removing the lip and banding pigment is confirmed; faint pink or yellow-white shells homozygotes for hyalozoneate may be genetically faint pinkor pale pink; the strong linkage between it and shell colour previously suggested is confirmed, but crossovers are recorded.
Abstract: The following segregants of shell colour are described: pale brown, faint brown, faint pink, yellow-white. Faint pink is dominant to dark and pale yellow and recessive to pale pink. Murray’s finding that the hyalozonate gene when homozygous pales shell colour as well as removing the lip and banding pigment is confirmed; faint pink or yellow-white shells homozygous for hyalozonate may be genetically faint pink or pale pink. Deep pink hyalozonates exist and transmit their phenotype to their offspring; in these the paling effect is not noticeable. Shells with no bands but a strip of fascialbate opaque material in the position for bordering the middle band are genetically mid-banded. The condition is due to a multifactorial suppression of the pigmented band. Spread-banded is described in the five-banded form as well as the m id-banded; the strong linkage between it and shell colour previously suggested is confirmed, but crossovers are recorded. White lip (with normally pigmented bands) is recessive to normal lip, linked to the locus for shell-colour, and allelic to hyalozonate. The normal lip/white lip heterozygote appears to be palelipped, but the degree of pallor is modified by the presence of yellow or pink shell colour. White lip, when homozygous, may reduce the intensity of shell colour in some cases, as does hyalozonate. Hyalozonate is shown to be linked to the banding locus, which itself is strongly linked to that for shell colour. Orange-banded is complementary to hyalozonate, not allelic to it as is the very similar form lurida described by Murray in Cepaea hortensis . A form of the var. punctata producing only traces of bands and occasionally a definite punctate band is described, which is linked to the shell colour locus and dominant to normal bands. This and the form figured by Lang and by Taylor with well-developed punctate bands (the segregation of which from normal bands is confirmed) may well be alleles. A segregation of medium grey to very pale body is described, with medium grey dominant to pale. It appears to be unlinked to shell colour, banding and mid-banded.

Journal ArticleDOI
TL;DR: The analysis supported the idea that the spontaneous movements of the ions through the system might concentrate glycine in the cells significantly by purely physical means (Christensen's hypothesis).
Abstract: 1. The tumour cells were starved in a solution lacking Na(+) and then transferred to a Ringer solution containing 2mm-sodium cyanide, 150m-equiv. of Na(+)/l. and 10m-equiv. of K(+)/l. Such cells were depleted of ATP and contained an endogenous pool of various amino acids equivalent to a 26mm solution. 2. At 4min. after the transfer the cellular Na(+) content had increased by about 100% and roughly an equivalent amount of K(+) had left the cells. 3. Under these conditions [(14)C]glycine was absorbed from an 11mm solution and reached the same cellular concentration by about 4min. The pool size increased by approximately the same amount (DeltaGly), so glycine did not simply exchange with the endogenous components. 4. After 4min. with glycine, the cells contained about 20% more Na(+) (DeltaNa(+)) than the control and about 10% less K(+) (DeltaK(+)). The mean values of DeltaNa(+)/DeltaGly and DeltaK(+)/DeltaGly from five experiments were respectively 0.90+/-0.11 and 0.62+/-0.11equiv./mole. 5. A further indication that these two ratios were not equal was that the cells absorbed more water than the movement of glycine itself required. The excess of water was osmotically equivalent to 0.95+/-0.16equiv. of solute/mole of glycine absorbed. 6. The variation of DeltaNa(+)/DeltaGly with the duration of the incubation was consistent with the stimulated uptake of Na(+) being linked to the actual transport of glycine. The same may apply to the movement of K(+), though the time-dependence was not examined in that case. 7. The observations were analysed in terms of a model in which both K(+) and Na(+) moved with a glycine-carrier system without ATP being involved. The analysis supported the idea that the spontaneous movements of the ions through the system might concentrate glycine in the cells significantly by purely physical means (Christensen's hypothesis).

Journal ArticleDOI
TL;DR: The results of an electrical resistivity study of G.P. zone formation in copper-beryllium alloys from 3.3 to 12.6 at.% are reported in this article.