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We discuss the objection raised by Halliday and Sachrajda against the inclusive sum-rule proof of the vanishing of the triple-Pomeron coupling at zero momentum transfer. We show that the graph which they have examined yields a negative divergent (when s → ∞) contribution to the inclusive cross section. Consideration of an infinite sum of graphs is necessary in order to complete this proof.

Correlation coefficients (CC) for two large transverse momentum hadrons are studied in the constituent interchange model. For p+p→π°+π°+X when the two π°'s are produced in opposite directions with momenta pTC, pTD the model predicts significant structure of the CC at pTC ≃ pTD; and when the two π°'s are produced in the same direction it predicts a very small CC. Comparison with existing data is also given.

An investigation was made into the nature of the role played by the noradrenergic innervation of the pacinian corpuscle. Corpuscles of the cat mesentery and mesocolon were used in all experiments. Blockade of noradrenergic beta receptors by dichloroisoproterenol and interference with norepinephrine release by reserpine are each capable of reversibly blocking mechanoelectric transduction by the pacinian corpuscle. The monoamine oxidase inhibitors iproniazid and phenelzine are capable of protecting the transducer from the blocking effects of reserpine. It is concluded that the presence of norepinephrine, as maintained by sympathetic tonus, is required for the afferent nerve terminal of the pacinian corpuscle to be mechanosensitive.

Extract: Blood glucose levels and rates of excretion of insulin in urine were measured in 31 infants with erythroblastosis. Twenty-two of these infants had determinations of insulin excretion in urine performed during the first 24 h of life. These infants can be divided into two groups. Group 1 were infants of greater than 36 weeks gestation. When using hemoglobin as the index of severity of the disease, they can be subdivided into two groups. Group 1A (six infants with a cord hemoglobin value of greater than 13 g/100 ml) had a mean excretion ratio of insulin/creatinine in urine of 6.9 μU/mg compared with a mean of 5.4 μU/mg for the control group (P = 0.5). Group 1 B (six infants with a cord hemoglobin value of less than 13 g/100 ml) had a mean value for insulin in the urine of 47.0 μU/mg, compared with a mean value of 5.4 μU/mg for the control group. Group 2, composed of 10 infants of less than 36 weeks gestation, had a mean value for insulin in urine of 129.7 μU/mg, compared with a mean of 21.9 μU/mg for the control group (P < 0.01). Excretion of insulin was inversely related to blood glucose. Seven infants were hypoglycemic (blood glucose levels of less than 20 mg/100 ml) and all had elevated insulin levels in urine. Speculation: In erythroblastotic infants, simultaneous occurrence of islet cell hyperplasia, hypoglycemia, and hyperinsulinuria is indicative of increased insulin production. The cause of the islet cell hyperplasia is not apparent. The placenta is commonly hyperplastic, and hence, its ability to destroy insulin may be enhanced, thus causing islet cell hyperplasia. At birth, separation of the infant from the placenta leads to an abrupt decrease in the infant's rate of insulin destruction, and thus, to temporary over-production of insulin. This hypothesis is in keeping with the observed early hypoglycemia and the normal birth weight for gestational age.

A unified description of vector-meson production and pseudoscalar-meson photoproduction is presented. An absorptive Regge-cut model is used to determine, from fits to π N → ω N, γ N → ( π 0 , η )N and π − p → ϱ 0 n data, the amplitudes of the absorbed Regge exchanges which are included in the analysis: ϱ , B, ω , π and A 2 . VDM is used to relate neutral pseudoscalar-meson photoproduction to the corresponding hadronic processes. The Regge residues have NWS zeroes and constraints from VDM, SU(6) and EXD are imposed on the parameters. Predictions are given for ϱ ± production, in good agreement with the data. The possibility of predicting π ± photoproduction through VDM is discussed. It is proposed that VDM be broken only in the pion contribution, but keeping the residue of the pole at t = μ 2 fixed from ϱ-production, which amounts to having the same elementary pion in processes related by VDM.

The method of half-range polynomials is applied to neutron transport theory. The specific applicability of this method to problems having discontinuities in the nuclear parameters at the boundaries or interfaces is discussed. Half-range polynomial expansions are used to obtain solutions for both finite and semi-infinite slabs, which consist of isotropically scattering media. The results indicate that the half-range approximations compare favorably with higher approximations obtained from the full-range spherical harmonic or several discrete ordinate methods. In particular, the poor convergence, found in the full-range methods in regions close to the discontinuity, is not present in the halfrange method. The latter method is used to obtain a pair of second-order coupled differential equations, as in diffusion theory. (auth)

An extension of Yvon's method to two-dimensional transport theory is given. The detailed formalism in P1 approximation is presented. Some pilot calculations on two-dimensional critical sizes perfor...

Recently proposed Regge-pole models are tested by means of FESR in π Open image in new window scattering. The crossing odd amplitude does not require more sophisticated models than the pure ρ-exchange model. In the crossing even case, several models can reproduce the data within the same accuracy. We also analyse the K Open image in new window total cross-sections and find that a conventional model allows us to fit the data within the errors (both statistical and systematic).

The pionic disintegration of the deuteron and its inverse process are studied in a covariant theory from threshold to 300 MeV pion kinetic energy. The singularity structure of the scattering amplitude as found from box diagrams makes it possible to select the leading contributions that come from the nucleon pole, the deuteron structure and the NN and NN π intermediate states. The latter is treated as an NN ∗ state where N ∗ is the (3.3) pion nucleon resonance. Dispersion relations are written for partial wave amplitudes and the contribution of the NN ∗ state to unitarity is explicitly calculated, taking into account the spin and the unstability of N ∗ . A detailed comparison in the medium energy region shows a good agreement with the existing data.

When the sensory fiber of a Pacinian corpuscle (in cat mesentery) is transected (at the inferior mesenteric nerve) transduction fails within 30 hours: the nerve ending produces no generator potentials in response to mechanical stimulation. Electrically elicited nerve impulse conduction continues for at least another 18 hours. A transducer mechanism develops on a regenerating nerve fiber when this fiber enters the denervated corpuscle. Such transducer development takes place on myelinated fibers from the inferior mesenteric nerve, which normally supplies corpuscles, as well as on myelinated hypogastric nerve fibers, which normally do not go to corpuscles, including fibers larger than the original corpuscle afferents.

In order to study inelastic unitarity in deuteron photodisintegration, the photoproduction ofN* on deuteron is calculated in the framework of impulse approximation. Predictions for the ratio ofN* photoproduction on deuteron and deuteron photodisintegration cross-sections are given for a proton momentum ranging from 200 MeV to 700 MeV. It is shown that this ratio is measurable.

An extension of the Veneziano model to PS-V elastic scattering is presented, in which the mother Regge trajectory of each family considered has definite parity (both possibilities are considered: natural and unnatural parity dominance). The formulae obtained are then discussed from different points of view: factorization is not trivially satisfied in general, even for mother trajectories; the Adler self-consistency conditions are not automatically fulfilled, but one can impose them by relating the natural and unnatural parity contributions; as to superconvergence and finite-energy sum rules, they give rise to some difficulties, which, although not specific of the spin case, are increased in this situation.

Summary 1. The competitive binding of oleate and bilirubin to albumin was evaluated in vitro using three different methods; reserve albumin binding capacity by HBABA dye, Sephadex G-25 gel filtration, and bilirubin spectral curves. 2. In a bilirubin-albumin solution of molar ratio 1.6, the percentage depression of reserve albumin binding capacity was linearly proportional to the amount of oleate added. 3. The Sephadex G-25 technique showed that actual displacement of bilirubin did not occur until the concentration of oleate exceeded 1.5 mEq/L; a finding confirmed by bilirubin spectral curve analysis. At this oleate concentration there was already a 40–50% depression of the reserve albumin binding capacity. 4. These findings suggest that the assessment of reserve albumin binding capacity is non-specific for bilirubin or for any of its competing anions and cannot distinguish between competitive and non-competitive binding to albumin. 5. The Sephadex G-25 method yields more meaningful quantitative data in terms of actual displacement of bilirubin by any other anions in the system under study.

The directional correlations of low intensity gamma-gamma cascades have been measured using NaI scintillation counters in a coincidence arrangement of 1.5\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}8}$ second resolving time. The correlation in the 3 percent intensity 191-1089-kev cascade in ${\mathrm{Co}}^{59}$ is compatible with a $\frac{3}{2}\ensuremath{-}\frac{5}{2}\ensuremath{-}\frac{7}{2}$ spin assignment. The coincidences from the 284-80-kev cascade in ${\mathrm{Xe}}^{131}$ are isotropic within an error of 2 percent, supporting the assignment of spin \textonehalf{} to the 80-kev level. The large correlation observed in the \ensuremath{\sim}1 percent intensity 680-411-kev cascade of ${\mathrm{Hg}}^{198}$ characterizes the spins of the levels involved as 2, 2, 0 and the 680-kev transition as a mixture of 60 percent $E2$ and 40 percent $M1$.

The eikonal model for high-energy pp scattering is extended to include spin effects. The single scattering corresponds to the exchange of a flat Pomeranchukon and two (degenerate) secondary trajectories. A very simple parametrization with five arbitrary parameters is chosen. We obtain a good description of the pp data on total and differential cross-sections. the ratio of real to imaginary part of the amplitude at t = 0 and polarizations. for incident momenta between 5 and 20 GeV/c. Predictions for the\(p\bar p\) high-energy scattering, are made. They are in reasonable agreement with the experimental data and exhibit the cross over effect near the right value of the momentum transfer. Some general features of the cikonal model are also discussed.

The violation of the Pomeranchuk theorem is shown to induce an energy trend for the small t π−p → π°n polarization which may differ notably from the conventional model predictions already in the range 20

Silverman and associates,1 reported that the use of sulfisoxazole (Gantrisin) in premature infants resulted in the occurrence of kernicterus at low levels of serum bilirubin. Odell2 subsequently demonstrated that sulfisoxazole displaces bilirubin from its albumin binding sites in vitro, thereby making available lipid soluble free bilirubin capable of penetrating the central nervous system. This effect of sulfisoxazole in producing kernicterus has been confirmed experimentally in vivo in rats.3 Odell4 and Khanna, et al.5 have demonstrated a similar but quantitatively even greater bilirubin displacing effect of caffeine sodium benzoate, a drug still recommended by some as a respiratory stimulant for the newborn.

The “binding” affinities and capacities of [ 3 H]-γ-aminobutyric acid ( 3 H-GABA) and [ 14 C]-glycine to synaptosome-enriched fractions of rat cerebral cortex and spinal cord have been compared over a 10 −8 to 10 −3 m concentration range in isosmotic sucrose solutions containing 32 m m NaCl. At 0 C, the binding of both GABA and glycine to particles of the cerebral cortex appeared to take place by “triple-affinity” processes. The respective binding affinities (reciprocals of K B values) of GABA for particles of the cortex were generally greater than those for glycine, whereas maximal binding capacities ( B max values) for GABA were about twice as great as those for glycine. In fractions of spinal cord, at 0 C, the binding of both GABA and glycine occurred by “double-affinity” processes, and though the binding affinities of GABA were about twice those of glycine, B max values for GABA were smaller than those for glycine. Striking changes occurred when particles were allowed to stand in contact with [ 3 H]-GABA plus [ 14 C]-glycine at 23 C for 45 min. Although double-affinity mechanisms persisted at the higher temperature for the binding of both amino acids to particles of spinal cord (GABA still being bound with greater affinities than glycine), the binding of both amino acids to particles of cerebral cortex was best resolved as “single-affinity” processes. The differences between B max values for GABA and glycine in particles of cerebral cortex and spinal cord appeared to reflect their different endogenous concentrations.

Summary: Pneumopericardium developed in three newborn infants, including a set of twins, with respiratory distress syndrome. The rarity of this condition and its occurrence in two newborns suggest an anatomic predisposition, especially in premature infants requiring assisted ventilation. Two of the infants died; one had undergone pericardiocentesis. From a review of the literature and from our cases we conclude that conservative therapy appears warranted in cases of isolated pneumopericardium although the number of cases reported is too small to provide a definite answer.

A case of Reye's syndrome in a newborn infant, believed to be the first recorded in the perinatal period, is reported. The clinical, biochemical and histological findings are those previously recognized in older infants. The intractable acidosis, hypoglycemia and extreme degree of lactic acidosis reflect an advanced degree of hepatic involvement, probably initiated in utero, with resultant impairment of glycogenolysis and intermediary metabolism.

Three infants whose diabetic mothers were given chlorpropamide and one infant whose diabetic mother was given acetohexamide up to the time of delivery were studied in the neonatal period because each became severely hypoglycaemic. The sulphonylurea drugs given to the mother crossed the placenta, and fetal plasma concentrations were in the therapeutic range for adults with diabetes mellitus. Each baby had severe hyperinsulinaemia resulting in profound hypoglycaemia. These acutely ill infants needed vigorous and prolonged treatment to correct the hypoglycaemia. In two infants exchange transfusion was performed to remove the drug. These sulphonylurea drugs should not be used to control diabetes mellitus in pregnancy.

Eighteen Peking ducklings were imprinted and tested for their tendency to emit distress calls during the presentation and withdrawal of the imprinted stimulus. A subsequent arrangement in which each distress vocalization led to a 5-second presentation of the imprinted stimulus resulted in an enhanced tendency to emit distress calls.

Direct intra-uterine transfusion of the foetus, for the treatment of rhesus iso-immunisation, was performed in 23 single babies and three sets of twins. Needling under radiological control was performed 49 times. Cases were selected on the basis of an obstetric history of babies affected by haemolytic disease and by spectrophotometric analysis of the liquor. Only those babies in whom intra-uterine death before the 34th week of pregnancy was considered a likely outcome were chosen for transfusion. The technique consisted of introducing O Rh negative red cells into the foetal peritoneal cavity where they were absorbed directly into the circulation and could combat the anaemia which we feel is the underlying basis of erythroblastosis foetalis. An attempt was made to opacify the foetus the night before the radiographic part of the procedure, to facilitate needling in the X-ray department. A preliminary film was taken with markers, and then needling of the baby's peritoneal cavity under fluoroscopic c...

Pildes, et al. have speculated on the discrepancy observed between umbilical venous and peripheral venous sampling for blood glucose and plasma insulin during oral glucose tolerance tests in the newborn infant. Since the liver is a major source of insulinase activity, it will metabolize, in part, the insulin released by the pancreas. Thus, insulin measured peripherally or post hepatically, will not be the same as that measured in the umbilical vein from a pre-hepatic placement of the catheter tip.