Showing papers by "Queen's University Belfast published in 1969"
TL;DR: An attempt is made to explore the logical foundations of computer programming by use of techniques which were first applied in the study of geometry and have later been extended to other branches of mathematics.
Abstract: In this paper an attempt is made to explore the logical foundations of computer programming by use of techniques which were first applied in the study of geometry and have later been extended to other branches of mathematics. This involves the elucidation of sets of axioms and rules of inference which can be used in proofs of the properties of computer programs. Examples are given of such axioms and rules, and a formal proof of a simple theorem is displayed. Finally, it is argued that important advantages, both theoretical and practical, may follow from a pursuance of these topics.
2,638 citations
TL;DR: Transfer cells are apparently restricted to situations where adverse surface area—volume relationships exist between donor and receptor compartments of the transport pathway and/or where the transported solutes are accompanied by a minimal flow of solvent.
Abstract: Plant cells possessing ingrowths of wall material, and hence having protoplasts with unusually high surface-to-volume ratios, may be found in a wide variety of anatomical situations and in most of the major taxa of multicellular plants. They are termed here “transfer cells”. Their function relates to any of four categories of trans membrane flux: 1. Absorption of solutes from the external environment (e.g. epidermis of submerged leaves), 2. Secretion of solutes to the external environment (e.g. nectaries and other glands), 3. Absorption of solutes from an internal, extracytoplasmic compartment (e.g. vascular parenchyma, haustorial-type connections, embryo sacs and embryos), 4. Secretion of solutes into an internal extracytoplasmic compartment (e.g. tapetum of anther, pericycle of root nodule). An overall assessment of their occurrence, structure, development and role in the plant is presented taking account of published information and new observations.
469 citations
TL;DR: In this paper, a theory of third-harmonic generation by focused beams is presented which is used to derive atomic (or molecular) thirdharmonic coefficients from the experimental data, and an ambiguity in choice of a sign leads to two alternative sets of coefficients.
Abstract: Optical third-harmonic generation at 2314 \AA{} using a focused ruby laser beam (6943 \AA{}) has been observed in a number of gases. A theory of third-harmonic generation by focused beams is presented which is used to derive atomic (or molecular) third-harmonic coefficients from the experimental data. An ambiguity in choice of a sign leads to two alternative sets of coefficients. One set is preferred on the basis of general agreement with data given in or derived from the literature: Theoretical calculations of the third-harmonic coefficients, measurements of the Kerr effect and theoretical dc hyperpolariabilities. For helium the measured absolute value is ${\ensuremath{\chi}}_{\mathrm{He}}=(7\ifmmode\times\else\texttimes\fi{}{3}^{\ifmmode\pm\else\textpm\fi{}})\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}39}$ esu/atom. For other gases the experimental values of $\ensuremath{\chi}$ in units of ${10}^{\ensuremath{-}39}$ esu/atom and scaled to ${\ensuremath{\chi}}_{\mathrm{He}}=4.0$ (a theoretical value due to Sitz and Yaris which is thought to be reliable to about 1%) are: Ne 8.9 \ifmmode\pm\else\textpm\fi{} 1.5; Ar 126 \ifmmode\pm\else\textpm\fi{} 20; Kr 386 \ifmmode\pm\else\textpm\fi{} 75; Xe 979 \ifmmode\pm\else\textpm\fi{} 150; ${\mathrm{H}}_{2}$ 80 \ifmmode\pm\else\textpm\fi{} 12; C${\mathrm{O}}_{2}$ 156 \ifmmode\pm\else\textpm\fi{} 23; ${\mathrm{N}}_{2}$ 107 \ifmmode\pm\else\textpm\fi{} 11. Some data for ${(\mathrm{C}{\mathrm{H}}_{2})}_{2}$, ${\mathrm{Cl}}_{2}$, ${\mathrm{O}}_{2}$, air, and glass are also presented.
339 citations
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TL;DR: The evidence incriminating insulin and carbohydrate is considered strong and would link atherosclerosis with diabetes obesity hyperlipidemia lack of physical exercise and possibly hypertention and use of contraceptive drugs.
268 citations
TL;DR: The structure of the vascular tissues of nitrogen-fixing nodules of 27 genera of legumes and some non-legumes has been investigated by light microscopy and a pathway for symplastic lateral transfer of assimilates exists, from the sieve elements through the pericycle, endodermis and cortex, is described.
Abstract: The structure of the vascular tissues of nitrogen-fixing nodules of 27 genera of legumes and some non-legumes has been investigated by light microscopy. Pisum and Trifolium nodules have been examined by electron microscopy. Attention is directed to the presence of a pericycle in the vascular bundles of the nodules. In 7 of the legumes the pericycle cells possess a wall labyrinth consisting of branched filiform protuberances. The ultrastructure of the pericycle cell cytoplasm is described: its most striking feature is its abundant rough endoplasmic reticulum. These cells surround the xylem and phloem of the bundles, and are in turn surrounded by a layer of endodermal cells with Casparian strips. The pericycle cells develop their wall labyrinth in the levels of the nodule at which the bacterial tissue becomes pigmented; in nodule senescence their cytoplasm is disrupted level with the breakdown of the bacterial tissue. A pathway for symplastic lateral transfer of assimilates exists, from the sieve elements through the pericycle, endodermis and cortex to the bacterial tissue. The apoplast within the endodermis consists largely of the pericycle wall labyrinth and the xylem. The ultrastructure of the Casparian strip resembles that of roots. Intact, detached nodules can be induced to bleed a fluid from their severed vascular tissue. This fluid is exceptionally rich in organic nitrogen, particularly amides, but does not appear to contain sugars. Comparison between its amino acid composition and that of other parts of the nodule suggests that an active uptake or secretion of nitrogenous compounds precedes export from the nodule. Special functions are suggested for the nodule endodermis and the pericycle cells in this export process.
172 citations
TL;DR: Experiment indicates that during 12 hours following the release of flooding, plants previously flooded for 72 hours or less recover their ability to exude sap when the root systems are aerated, and theRoot systems synthesize and export amino-acids to the shoot.
Abstract: The severe chlorosis observed in the lower most of flooded sunflower plants (Helianthus annuus L. cv. Tall Single) may lie initiated by a reduction in the import of cytokinins by the stoot from the flooded root system. Experiment indicates that during 12 hours following the release of flooding, plants previously flooded for 72 hours or less recover their ability to exude sap when the root systems are aerated, and the root systems synthesize and export amino-acids to the shoot. Plants flooded for longer periods lose these abilities. The metabolic activity of the root apices declines parallel with the decline in eytnkinin concentration in the sap with increase in flooding time up to 72 hours. Flooding for 96 hours drastically reduce all four parameters of root activity. After flooding for this period there was a large increase in the number of blackened and tetrazolium-negative root apices which were in all probability dead. The correlation between the metabolic activity of the root apices and the total cytokinin content of the sap supports tbe view that root apices may be sites of cytokinin synthesis.
140 citations
TL;DR: The functional significance of transfer cells in minor veins is discussed in relation to the loading and unloading of the conducting elements and to the retrieval of extra-cytoplasmic solutes from the mesophyll and the transpiration stream.
Abstract: A study of the fine structure of minor veins of mature leaves of 975 species and 242 families of Angiosperms shows that transfer cells are widespread amongst herbaceous Dicotyledons, are much rarer in woody Dicotyledons, and are virtually absent from the Monocotyledons. The evolutionary significance of the distribution of the cells amongst and within orders, families and minor groupings is discussed. Four types of transfer cell are recognized in minor veins, all possessing irregular ingrowths of wall material protruding into their protoplasts, and all being regarded as modified parenchyma of the minor vein. Two types occur in phloem. One (the A-cell), with ingrowths distributed right round its periphery, is associated specifically with the sieve elements. The other (the B-cell) occurs more generally throughout the phloem and has zones of wall ingrowths oriented towards sieve elements and their associated companion cells or A-cells. Two other types (C- and D-cells) occur in xylem parenchyma and bundle sheath respectively, and have ingrowths only on walls in contact with or in close proximity to vessels or tracheids. Each species has a characteristic combination of types of transfer cell. The variations encountered in the survey are classified. Consistent differences in the frequency and form of ingrowths are to be found between the different types of transfer cell of a single species, and between different species in respect to a particular type of transfer cell. The functional significance of transfer cells in minor veins is discussed in relation to the loading and unloading of the conducting elements and to the retrieval of extra-cytoplasmic solutes from the mesophyll and the transpiration stream.
118 citations
TL;DR: In this paper, a modified close-coupling expansion was developed and applied to calculate elastic electron-hydrogen-atom scattering phase shifts, where the first few hydrogen-atom eigenstates were retained and augmented with pseudo-states chosen to incorporate the ground-state polarizability of the hydrogen atom.
Abstract: A modified close-coupling expansion has been developed and applied to calculate elastic electron-hydrogen-atom scattering phase shifts. This expansion into a complete discrete orthonormal basis set is a variant of the more usual close-coupling expansion into eigenstates of the target Hamiltonian. We retain the first few hydrogen-atom eigenstates and augment these terms with pseudo-states chosen, in our particular case, to incorporate fully the ground-state polarizability of the hydrogen atom. The resulting phase shifts are compared, where possible, with those obtained in the most accurate variational calculations available, and they indicate a distinctly improved convergence over those obtained in the close-coupling expansion.
109 citations
TL;DR: For myself, earthbound and fettered to the scene of my activities, I confess that I do feel the differences of mankind, national and individual, I am, in plainer words, a bundle of prejudices - made of likings and dislikings - the veriest thrall to sympathies, apathies, antipathies (Charles Lamb, quoted by Allport, the authors ).
Abstract: For myself, earthbound and fettered to the scene of my activities, I confess that I do feel the differences of mankind, national and individual …I am, in plainer words, a bundle of prejudices - made of likings and dislikings - the veriest thrall to sympathies, apathies, antipathies (Charles Lamb, quoted by Allport,). Segregation, on the basis of both economic and ethnic characteristics, is a feature of most cities. Segregation is usually measured on the basis of the spatial distribution of individuals or households belonging to a particular economic or ethnic group. Most commonly, the actual distribution of group members is compared to the pattern that would exist if the group members were distributed evenly throughout the area under study - the deviation between the actual and even distributions forming a measure of the degree of segregation.
105 citations
TL;DR: In this article, the close-coupling equations for electron-helium scattering have been solved in the energy range near the $n=2$ thresholds and cross sections for elastic scattering from both ground and excited states are presented and compared with experimental evidence on total metastable production, on angular distributions of excitation cross sections to the n-2$ levels, and on processes involving only the n−2$ states.
Abstract: The close-coupling equations for electron-helium scattering have been solved in the energy range near the $n=2$ thresholds. Cross sections for elastic scattering from both ground and excited states, for excitation of the ground state to the $n=2$ states ($2^{3}S$, $2^{1}S$, $2^{3}P$, and $2^{1}P$), and for excitation and de-excitation processes involving only the $n=2$ levels are presented and compared with experimental evidence on total metastable production, on angular distributions of excitation cross sections to the $n=2$ levels, and on processes involving only the $n=2$ states. The percentage polarization of light emitted by electron-impact excitation to the $2^{3}P$ and $2^{1}P$ states is computed and compared with experiment. The calculations indicate the importance of resonances in near threshold excitation and de-excitation processes in He. An attempt has been made to understand the resonant structure by considering both the energy dependence of the eigenphases of the many-channel $S$ matrix produced by solving the close-coupling equations and the energy dependence of eigenvalues of the related time-delay matrix.
103 citations
TL;DR: The lethal effects of isoprenaline in dogs artificially respired with room air or with 12% oxygen—88% nitrogen could be prevented by pretreatment with propranolol.
Abstract: 1. The effects of the intravenous injection of isoprenaline on heart rate and arterial pressure has been studied in dogs artificially respired with room air or with 12% oxygen-88% nitrogen.2. In dogs breathing room air, isoprenaline in doses from 0.02 to 500 mug/kg increased heart rate and reduced arterial pressure. Ventricular fibrillation was produced in one out of three dogs given 250 mug/kg. This was the only dog breathing room air which was killed by isoprenaline.3. In dogs breathing room air the repeated intravenous injection at 5-min intervals of 2.5 mug/kg increased heart rate and reduced arterial pressure. No ill effects were produced by six doses.4. In dogs respired with 12% oxygen-88% nitrogen the PaO(2) was reduced from 84 to 38 mm Hg with no changes in PaCO(2). In these dogs death was produced by doses of isoprenaline which in dogs breathing room air produced normal responses.5. The fatal dose of isoprenaline (10-50 mug/kg) reduced heart rate and arterial and pulse pressures; sinus rhythm persisted until arterial pressure was less than 50 mm Hg. Ventricular fibrillation did not occur; death occurred from cardiac asystole.6. Death was produced in a similar way in dogs with hypoxaemia by giving four or five doses of isoprenaline (2.5 mug/kg) at 5-min intervals or by two doses of 25 mug/kg.7. The final reduction in arterial pressure during a fatal response resulted from a reduction in cardiac contractility.8. These lethal effects of isoprenaline could be prevented by pretreatment with propranolol.
TL;DR: In this paper, the 2s, 2p close-coupling equations for electron scattering by lithium atoms are solved from threshold to 544 ev, and the elastic scattering and 2s-2p excitation cross sections are evaluated.
Abstract: The 2s, 2p close-coupling equations for electron scattering by lithium atoms are solved from threshold to 544 ev. Both the elastic scattering and the 2s-2p excitation cross sections are evaluated. At very low energies the cross sections are shown to be dominated by resonances. At energies between 1 ev and 10 ev the total cross section can be compared with experiment. Any lack of agreement cannot be explained simply by the slow convergence of the close-coupling approximation. Finally, the spin polarization cross section and the polarization of 2p-2s impact radiation are calculated. Comparison of the latter calculation with experiment is satisfactory.
TL;DR: In this article, an analysis of the fatty acids of cucumber cotyledons showed that changes occur in the composition of both the free and esterified fatty acid fractions.
TL;DR: It is demonstrated that Gibberellin-like substances can promote stem elongation in intact tomato plants and decline in growth rate following waterlogging may be due to the reduction in the supply of GAs to the shoot.
Abstract: Gibberellin (GA)-like substances are shown to be present in the bleeding sap of tomatoes. It is demonstrated that these substances can promote stem elongation in intact tomato plants. Waterlogging of the root system inhibits stem growth and severely reduces the export of GAs from the root to the shoot in the xylem sap. It is suggested that decline in growth rate following waterlogging may, in part, be due to the reduction in the supply of GAs to the shoot.
TL;DR: In this paper, the wave function of the e--He+ system is expanded as a sum of close-coupling states together with a number of short-range correlation terms, and the scattering matrix is evaluated in the energy range between the n = 2 and n = 3 thresholds.
Abstract: The wave function of the e--He+ system is expanded as a sum of close-coupling states together with a number of short-range correlation terms. The scattering matrix is evaluated in the energy range between the n = 2 and n = 3 thresholds. The convergence of the expansion of the wave function is discussed and comparison is made with recent experiments for the 1s-2s excitation cross section.
TL;DR: A double blind trial of prednisolone treatment was carried out on 95 children with clinical evidence of epidemic bronchiolitis and showed that there was no difference between the prednisoIone and the placebo group in the duration of symptoms and signs.
Abstract: Summary
A double blind trial of prednisolone treatment was carried out on 95 children with clinical evidence of epidemic bronchiolitis. The trial showed that there was no difference between the prednisoIone and the placebo group in the duration of symptoms and signs.
Eighty-four per cent of children were shown to be infected with respiratory syncytial virus. Prednisolone in the dosage used did not affect the antibody response to infection.
The presence of maternal antibody to respiratory syncytial virus, while not preventing infection, reduced the number of active antibody responses in children aged 3 months or younger.
Eight children had a double infection with respiratory syncytial virus and adenovirus which lengthened their average stay in hospital by two days and the overall duration of illness by more than three days.
TL;DR: The core cells as the principal features of caeca are considered to be storage centres for chemical components circulating with in the mantle, and although no continuous seepage through the periostracum to the shell exterior can be demonstrated, it probably acts as a cement when the peroastracum is broken and also inhibits penetration of the shell by boring organisms.
Abstract: Caeca, the tubular outgrowths of the mantle of endopunctate articulate brachiopods, which penetrate the shell to connect with the periostracum by a brush, have been examined under the electron microscope and subjected to standard histochemical tests. The brush consists of many tubes with a protein membrane, which permeate a thin canopy of calcite separating the periostracum from the distal head of a caecum; the tubes and space beneath the canopy are filled with mucopolysaccharide. Elongate core cells surrounded by flattened peripheral cells make up the caecal head. The core cells are usually distended with spheroidal inclusions of muco- and glycoprotein, particulate glycogen and protein, and minor lipid bodies. They hang freely into a lumen occupying the stalk-like proximal part of a caecum, while their distal surfaces beneath the brush are microvillous. The peripheral cells are charged with protein inclusions. The lumen within the caecal stalk is formed after the differentiation of a caecum on the outer lobe of the mantle, as an adjustment to a thickening exoskeleton. Proximally, it is bounded by outer epithelial cells but it extends medially to the basement membrane overlying the connective tissue of the mantle and is continuous laterally with intercellular spaces. The mucopolysaccharide in the brush and beneath the calcite canopy is derived from the core cells, and although no continuous seepage through the periostracum to the shell exterior can be demonstrated, it probably acts as a cement when the periostracum is broken and also inhibits penetration of the shell by boring organisms. The core cells as the principal features of caeca are considered to be storage centres for chemical components circulating within the mantle.
TL;DR: In this article, the elastic-plastic solutions of externally sharply notched tension bars, produced by digital computation using the Marcal-King finite element method, have been assessed with respect to notch stress intensifications and crack opening displacements, following an initial definition of the limitations of finite mesh size.
TL;DR: To ascertain the accuracy of claims that Pancuronium bromide is a muscle relaxant which is relatively free from side effectss-8 and the more detailed study of Bairdg supports this view, it is compared with d-tubocurarine in two similar groups of patients.
Abstract: A muscle relaxant which would be ideal for use during major surgery should have a rapid onset of action, a duration of 3MOminutes and should be readily reversible by anti-cholinesterase drugs. It should also be specific in producing a non-depolarised neuromuscular blockade and have no other side effects. d-tubocurarine, the pure alkaloid of the first relaxant ever used in anaesthesia, fulfils most of these criteria except that it is unfortunately not without side effects. The most important of these are hypotension, which probably results from autonomic ganglion blockade and the release of histamine, often associated with a skin flush and occasionally with bronchoconstriction. None the less this drug is still the most widely used relaxant, which is a good indication that no better drug has yet been found. Gallamine, introduced by Bovet, Depierre & De Lestrangel in 1947, causes persistent tachycardia, but has little other effect on the circulation and appears to be free from histamine releasing properties2. Diallyl toxiferine releases less histamine than d-tubocurarine3 but is less easily reversible and its administration is often associated with hypotension4. Under normal circumstances, however, reversal of neuromuscular block does not present a problem with any of this group of drugs and, it would seem, improvements in muscle relaxant drugs will be related to absence of side effects, rather than to anyaltered action at the neuromuscular junction. Pancuronium bromide is a muscle relaxant which was first synthesised in 1964 by Hewett & Savage and has subsequently been shown to produce a non-depolarizing type of neuromuscular block in animals5 and in man 68. Chemically it is a bisquaternary amino-steroid, free from hormonal action. Early clinical work has suggested that it is relatively free from side effectss-8 and the more detailed study of Bairdg supports this view. The object of the present investigation was to ascertain the accuracy of these claims, especially with regard to the cardiovascular system and to compare the drug with d-tubocurarine in two similar groups of patients.
TL;DR: There was no significant difference in the incidence of diarrhœa one year after operation, but a higher proportion of negative insulin tests was found in patients treated by the selective operation.
TL;DR: In this paper, a sub-picosecond structure ( s × 10 −13 sec) with a photographic peak contrast of ∼ 2.6, has been recorded in the two photon fluorescence patterns produced by mode-locked Nd: glass lasers.
TL;DR: In this paper, the authors applied Markov chains and discrete stochastic chains to a composite section of Upper Pennsylvanian strata of northeastern Kansas, and found a 40-to 50-ft "cyclicity", which is a property which ranges from completely damped to perfect periodic oscillations.
Abstract: Markov chains, applied to stratigraphic sections, are suitable for the description of geological cycles. Cyclicity is a property which ranges from completely damped to perfect periodic oscillations. A measurement of “cyclicity” is provided by the eigenvalues of the Markov matrix. At the same time, it was found that the method of Markov chains and discrete stochastic chains, in general, is a cumber-some tool when applied to stratigraphic analysis. Many sections require high-order chains and consequently larger transition probability matrices, which are difficult to interpret. Great care must be taken not to oversimplify these chains, because this results in a loss of cyclicity. By applying the methods to a composite section of Upper Pennsylvanian strata of northeastern Kansas, a 40- to 50-ft “cycle” was found. The oscillations are damped if directly measured data are used. Removal of a trend in sedimentation rates reduces damping to such an extent that the hypothesis of time cyclicity is at least feasible.
TL;DR: Significant losses of energy and nitrogen when drying poultry excreta samples were dried in a convection oven at 65°C for 24 hours would lead to serious errors in normally determined ME values and it was decided to reinvestigate these findings.
TL;DR: A stable inhibitor of spore germination has been isolated and characterised as nonanoic acid, and evidence is presented that this compound is widely produced among fungi and can inhibit the germination of spores of many fungal species.
Abstract: The level of inhibition of germination of spores added to cell-free culture filtrates of Fusarium oxysporum Schlecht. ex Fr. declines with time. This decline can be accounted for by the decreasing levels of volatile sporostatic factors and a stable vacuolation factor produced by F. oxysporum. After the disappearance of the volatile sporostatic factors, a stable principle is recognised in the culture filtrate by a persistent level of inhibition of spore germination which is not completely alleviated by the addition of nutrients. A stable inhibitor of spore germination has been isolated and characterised as nonanoic acid, and evidence is presented that this compound is widely produced among fungi and can inhibit the germination of spores of many fungal species. The contribution of nonanoic acid to sporostasis in cultures of F. oxysporum is assessed.
TL;DR: Arrian's enthusiasm for Ptolemy's account of Alexander has often been echoed in modern times as mentioned in this paper, and it is generally agreed that Arrian's account is the best and, on the whole, most reliable account of the story of Alexander.
Abstract: Arrian's enthusiasm for Ptolemy's account of Alexander has often been echoed in modern times. With much justification it is generally agreed that Arrian's account of Alexander, through its reliance on the works of Ptolemy and Aristobulus, is our best and, on the whole, most reliable account of Alexander. Recent work, however, has illuminated Ptolemy's weaknesses, and we can no longer regard Ptolemy as utterly reliable in every important respect. His version of the Alexander story is centred on Alexander, therefore Alexander is depicted out of the close context of the Macedonian court. It is only through the information preserved in other writers—traditionally, but undiscriminatingly, considered unreliable—that, for instance, the picture of Alexander's struggle with his Macedonian nobles has begun to emerge. And in matters of this kind Ptolemy's version is so much the court ‘official’ version that it cannot be regarded as trustworthy.
TL;DR: It may be postulated that cellular enzymes are liberated from damaged placenta as from infarcted heart muscle, although the method is widely used throughout the world today.
TL;DR: In this article, the impact parameter formulation H 2 + ( v 9 0 )-H 2 ( v " 0 ) collisions leading to H + 2 (v 9) -H 2(v 99) or to H 2( v 99) - H 2 (V 9 ) -H2 (V 99) is used to calculate the total charge transfer cross-section for vibrational excitation.
Abstract: By using the impact parameter formulation H 2 + ( v 9 0 )-H 2 ( v " 0 ) collisions leading to H + 2 ( v 9) — H 2 ( v 99) or to H 2 ( v 99) — H + 2 ( v 9) are treated. It is assumed that the ion and the molecule are in the ground electronic state so that only two electronic states of the complex are involved. The electronic interaction is evaluated by a simple extension of the m ethod of Firsov (1951). Taking it to be spherically symmetrical, the problem effectively reduces to solving a set of coupled first order differential equations, the coefficients of which depend on the H + 2 —H 2 vibrational overlap integrals. Cross-section curves for vibrational excitation with ( X ) and w ithout ( D ) charge transfer are presented. If the im pact velocity V is low, corresponding D and X cross-sections are about equal, but in the region of high V the former tends to fall off more rapidly than the latter. The total charge transfer cross-section in H + 2 (0) — H 2 (0) collisions, Q x (00→Σ | V) is calculated. As V is increased from zero Q x (00→ Σ | V) first shows the slow fall off characteristic of symmetrical resonance charge tran sfer; but it reaches a minimum when V is near 1 x 10 -1 a.u., then rises and passes through a maximum. This behaviour arises from the increase in the relative contribution to charge transfer from the inelastic collisions. To facilitate comparison w ith experim ent a study is also made of charge transfer when the H + 2 ions are distributed among the vibrational levels as they would be if they were produced by the im pact of fast electrons on H 2 molecules. The calculations on the weighted mean total charge transfer cross-section Q x (Σ | V) are confined to the low and high velocity limits. However, they are sufficient to indicate that Q x (00→ Σ | V) and Q x (Σ | V) are not markedly different. The predicted form of the cross-section curve is consistent with the laboratory data available.