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The Hg-CH 4 van der Waals complex has been studied in a supersonic jet expansion, in transitions correlated with the 6 1 S 0 →6 3 P 1 mercury transitions. Fuorescence excitation spectra and action spectra have been recorded to analyse the corresponding transitions X→A and X→B. Through isotopic substitution of methane with deuterated methane, the origin band is assigned, and the vibrations of the complex characterised in a simple quasi-diatomic fashion as stretching and bending motions of methane with respect to mercury. These motions correspond to the radial and angular potentials of the complex. Emission spectra from selected stretch levels in the A and B states have confirmed the vibrational quantum assignment and provided a full determination of the radial ground-state potential.

For studying the chemical reaction occurring when one of the collision partner is electronically excited, one can use the unique property of the intermolecular interaction: at long distance the potential is attractive and often present a small minimum, the van der Waals minimum. It is then possible by cooling the gas mixture of the reactives in a supersonic expansion to freeze the collisional complex into this van der Waals potential depth. The reactive process is triggered by an optical excitation, which promotes the system onto the reactive surface and the products obtained are analysed by laser induced fluorescence. In this technique all the entrance channel parameters are known: the kinetic energy is zero, and the partner are initially oriented. Moreover the spectroscopic studies of the complex give direct grasp of the potential energy surface, and on the alignment of the electronic orbitals upon the intermolecular axis.

The first Rydberg states of the HgAr van der Waals molecule have been characterized by a laser double-resonance technique. Two states have been observed, which correlate to Hg(7s 3 S 1 )+Ar( 1 S 0 ), a strongly bound state, C, in accord with theoretical expectations and a very weakly bound state, D, which is unexplained.

Bi-injection molding generally requires two independent injection device systems to introduce molten polymers into the mold cavity.Both the tickness and orientation of the two materials in the finished molded product are dependent on the viscosities of the polymers as well as the rheological properties.This paper deals with a new, easy, simple, inexpensive bi-injection technology capable of producing specific structures according to expected properties while varying skin thickness to the desired level, both with or without fillers.

The authors describe the ultrasonographic anatomy and semiology of allowing detection of the main types of fetal uropathies. The results of the author's personal experience in this domain are compared to data from the literature. Differential features of the uropathies are given and the limitations and practical significance of prenatal and postnatal ultrasonography are discussed.

The structure and the predissociation dynamics of an excited van der Waals (vdW) complex HgN2 which is produced in a supersonic jet, have been investigated by means of laser‐induced fluorescence (LIF) spectroscopy. The vibronic systems of the A–X and B–X transitions are analyzed in terms of the vdW bond stretching and the Hg–N2 bending modes. The predissociation process, HgN2(A or B)→Hg(3P0)+N2, in both of the A and B vibronic states has also been discussed by detecting Hg(3P0) as a predissociation product. Assignment of vibrational quantum numbers for the vdW bond stretching mode is made on the basis of the observed splittings among isotopic species for mHgN2 (m=198, 199, 200, 201, 202, and 204). Rotational contour analysis of the LIF and the 3P0 formation spectra is performed to determine (1) the branching ratio for the fluorescence and the predissociation processes as a function of vibrational and rotational quantum numbers and (2) potential functions for the A and B states along the vdW bond coordinat...

A purely classical model of massless test particle with spin s is introduced as the dynamical system defined by the ten‐dimensional O(4,2) co‐adjoint orbit with Casimir numbers (s2,0,0). The Mathisson, Papapetrou et al. equations of motion in a gravitational field are recovered, and the particle appears to travel on null geodesics. Several implications are discussed.

Fetal lung maturity has been studied both by silica gel chromatography of phospholipids and gas liquid chromatography of fatty acids. Lecithin/sphingomyelin (L/S) ratios and palmitic/stearic (P/S) ratios were compared. A good correlation was obtained. However, when the L/S ratio has an intermediate value (1.5 less than or equal to L/S less than 2) making it difficult to judge the fetal lung maturity, the P/S ratio expresses the lung maturity more accurately.

The reaction products of U(η-C 5 H 5 ) 2 (NEt 2 ) 2 with β-diketones depend on temperature. At low temperature (-20°C) with stoichiometric amounts of β-diketone, the compounds U(η-C 5 H 5 ) 2 (β-diketonato) 2 (II) are obtained as the major products. At higher temperature, or in the presence of an excess of β-diketone, loss of a cyclopentadienyl ligand occurs and the compounds U(η-C 5 H 5 )(β-diketonato) 3 (III) are isolated. The low temperature PMR spectra are consistent with “ cis ” octahedral coordination geometry around the metal atom in II, and with the geometry of a pentagonal bipyramid ( C 5 symmetry) in III.

Spatial and temporal variations in the abundance of young-of-the-year channel catfish Ictalurus punctatus were determined over 3 years based on 154 trawls taken from Navigation Pool 7 of the upper Mississippi River. No significant spatial patterns in abundance or length offish in the catch were found in seven poolwide surveys of the main channel. However, high variation among replicates existed. Temporal patterns in abundance and length-frequency distributions varied among the study years. Seasonal catch curves were similar in 1984 and 1986, although offset due to earlier spawning in 1986. Spawning appeared to have been protracted in both years, based on analyses of back-calculated dates of spawn and length-frequency patterns of young. Sixty to seventy percent more young were produced in 1985, when spawning occurred over a shorter period of time and a more uniformly sized year class was produced. These annual variations in year-class characteristics are hypothesized to have resulted in part from ...

This paper is a sequel to earlier ones, (1984), in which, on the one hand, classical field theories were described on a curved Newtonian spacetime, and, on the other hand, the Newtonian gravitation theory was formulated on a five-dimensional spacetime with a metric of signature (++++-) and a covariantly constant vector field. Here the authors show that Lagrangians for matter fields are easily formulated on this extended spacetime from simple invariance arguments and that stress-energy tensors can be derived from them in the usual manner so that four-dimensional spacetime expressions are obtained that are consistent in the relativistic as well as the Newtonian case. In the former the theory is equivalent to general relativity. When the magnitude of the distinguished vector field vanishes equations for the (covariant) Newtonian limit follow. They demonstrate this here explicitly in the case of the Klein-Gordon/Schrodinger and the Dirac field and its covariant non-relativistic analogue, the Levy-Leblond field. In especially the latter example the covariant Newtonian theory simplifies dramatically in this five-dimensional form.

Freeze-fractured thylakoids of Fucus serratus L. exhibit three types of faces with a particle density analogous to that of EFs, EFu and PF faces of green plants. However the particle size distribution is unimodal in the three types with a mean of about 8 nm. No obvious distinction between PFs and PFu faces could be detected. The absence on EFs faces of the distinct class of large particles (>13 nm) existing in green plant thylakoids implies a unique organization of pigment proteins, especially of the light-harvesting complexes.

A new technique is described for probing the reaction dynamics of “half-collisions” in systems where “full-collision” chemical dynamics can also be studied. By selective laser excitation of an atom-molecule van der Waal’s complex, an electronically excited atom can be created at a known distance from, and with a known orbital symmetry with respect to, the reactive molecule. From spectra of the complex and from detection of nascent products in a state-resolved fashion, not only can a great deal be learned about the dynamics of the “half-collision”, but comparison can also be made with analogous full-collision dynamical information. Reported here are results involving the Hg-H2 (63 P1 ) van der Waal’s complex, where the two different orientations of the Hg 6p orbital is shown spectroscopically to exhibit widely different reactivities.

Resume L'auteur a trace la courbe de pyrolyse de tous les precipites proposes pour doser gravimetriquement le plomb, apres avoir rejete la methode au cyanure, a l'hemateine et a l'acide salicylique; il compare les autres, fournit dans le tableau ci-dessus les limites des temperatures auxquelles il faut porter les precipites pour obtenir le resultat le plus convenable. Treize methodes peuvent servir au dosage automatique du plomb. Les deux meilleures, a tous les egards, utilisent le sulfure et le complexe avec le thionalide, ce dernier ayant naturellement la preference, a cause du faible facteur analytique pour le plomb.

Resume Les auteurs ont examine d'une facon critique, les reactions proposees pour le cobalt entre 1937 et 1947. Hs proposent de s'en tenir aux conclusions du deuxieme Rapport (Redactione wenger et duckert) Tontefois, la reaction avec le cyanate de potassium. Pourrait etre remplacee par 1'essai, presque similaire, avec le thiosulfate de sodium, reactif plus accessible, l'essai n'est pas trouble pas la presence du cuivre, du fer et du nickel.

Mercury helium and mercury xenon van der Waals complexes have been observed in a supersonic free jet expansion by laser-induced fluorescence in the vicinity of the Hg( 3 P 1  1 S 0 ) transition. The helium complex very weakly bonded in the ground state ( D 0 = 8 ± 1 cm −1 ) exhibited a simple rotational structure. The strongly bonded xenon complex has shown a clear example of isotopic broadening in its vibronic spectra.

From a retrospective study over 11 years of 375 ectopic pregnancies, the authors have analyzed the epidemiological factors that could account for a very sensible and regular increase of the frequency of this gravidic accident. If a past history of tubal infection is usually considered as a major cause, in this series, we must mainly consider the abnormal frequency of the use of a modern contraceptive method at the time of the ectopic pregnancy, found in 32% of the cases. The place and the role of intra-uterine devices are discussed since a coil was associated with an ectopic pregnancy in 22.5% of the patients while the notion of a previous usage does not seem to be a predisposing factor: approximately only 2% of these patients had resorted to it. A hormonal contraception in progress may also lead to a late diagnosis, especially in patients using mini and micro-pills (8% of ectopic pregnancies). Finally, the advantages of conservative tubal surgery contingent on an earlier diagnosis are kept in mind by the authors because of the persistence of a high recurrence rate on the contralateral side, even after salpingectomy.

The pathogenic role of mycoplasms during pregnancy remains quite controverted, depending on the studies; for some it has an incidence on prematurity, delayed growth in utero and premature rupture of the membranes. The purpose of this study was, from a population of patients with term delivery, without any specific pathology, to verify the frequency of mothers carrying Mycoplasma Hominis or ureaplasma, and to determine the possible consequences on the newborn. A linear analysis of the evolution of the samples between D0 and D6 in the mother and the new born, shows that the presence of mycoplasms in the genital passages is as frequent in this non-risk population, and that the child may be contaminated about every other time; but this contamination appears to be very transient and without any consequences on the immediate neo-natal pathology. Systematic screening of genital mycoplasms in pregnant women does not permit, therefore, to select a group of exposed patients. In newborns who are contaminated, the risk of infection appears to be very low, but it would perhaps be desirable to study the long range future evolution of healthy carriers.

In this study, the writers have taken as the basis of their investigation the anatomic and pathological analysis of samples studied as a matter of course after hemorrhoidal operations performed regularly at St Mark's Hospital. They describe their macro- and microscopic findings and, in the discussion, they summarise the development of our knowledge in this field, note the inconsistency between anatomical conclusions and clinical variations, stress the importance of the slipped vascular pad phenomenon, and reject the oft-cited concept of the existence of a corpus cavernosum in the rectum.

The electronic structure of 6p Hg-Ar complexes has been Investigated and described by a simple electrostatic model using the 6p average orientation with respect to the internuclear axis. The vibrational structure of the triatomic complex Hg-N2 was also described in terms of two vibrational modes, a stretching and a bending vibration. This description is essential as it is observed that the torsional modes with vibrational angular momentum Induce strong fine structure relaxation 3P1 – 3P0.

A longitudinal study of 103 cases of renal glycosuria (94 families) led to the following conclusions. 1. When the condition is genetically determined, it is probably inherited as an autosomal recessive. 2. There is no relationship with diabetes mellitus. 3. The renal glycosuria is persistent but does not get worse.

Hb Burke [beta 107 (G9) Gly replaced by Arg] was discovered in a young woman with hemolytic anemia. A substitution in this position has not been previously reported either in the human beta-chain or in any of the animal beta-chains so far sequenced. The abnormal hemoglobin shows heat instability and a lowered oxygen affinity. The substitution of a large charged arginine residue for the small glycine residue in the G helix next to a heme contact (Leu-106) may be responsible for these effects. Hb Burke is compared with five other hemoglobins having Gly-Arg substitutions in other parts of the molecule.

The authors are considering the prolapse of the umbilical cord, based on 79 personal observations collected in 15 years and data from the literature. They demonstrate that a simple approach (forcing back the presentation and caesarean section) decreases the perinatal mortality rate. The total rate of fetal deaths is 10 p. cent, the corrected rate of children dead on admission is 1.5 p. cent. 77 p. cent of caesarean sections were performed.

Pseudomonas aeruginosa alkaline protease (AP) has recently been shown to produce limited proteolysis of human gamma interferon (IFN-gamma) and thereby destroy the antiviral and macrophage-activating activities of the lymphokine. In the present study we describe some of the characteristics of Pseudomonas elastase (E) with regard to inactivation of human IFN-gamma. The inhibitory effect of E on IFN-gamma bioactivity differed from that of AP in that the direct effects of E were reduced in the presence of human serum. That this property of human serum was in large part attributable to the protease inhibitor alpha 2-macroglobulin (alpha 2-M) was suggested by the following observations: (i) methylamine treatment of serum reduced its effect on E, (ii) E interacted directly with alpha 2-M to induce a characteristic conformational change in the protease inhibitor, and (iii) preformed E-alpha 2-M complexes lacked IFN-gamma-degrading activity. Despite these findings, anti-E antiserum partially neutralized the effect that a Pseudomonas filtrate showed on IFN-gamma, suggesting that E contributes to the activity of bacterial filtrates. Treatment of IFN-gamma with E in the presence of a suboptimal concentration of AP resulted in an E dose-dependent inactivation of the lymphokine. Preformed E-alpha 2-M complexes, although ineffective by themselves at cleaving IFN-gamma, degraded the lymphokine, providing AP was also present in the reaction mixture. These data demonstrate that the destruction of small, biologically significant peptides by Pseudomonas proteases can involve protease-protease synergy that acts even in the presence of the serum protease inhibitor alpha 2-M.

The influence of tobacco smoke during pregnancy on haemoglobin concentration and oxygen affinity of smoker women has been studied. Fifty-nine non smoker (NSW) and forty-five smoker women (SW) were investigated during pregnancy and early puerperium. Results have shown: 1) a slight non significant increase in oxygen affinity of SW; 2) a significant decrease in oxygen affinity in SW at term and early puerperium, the same as in NSW; 3) a significant increase in haemoglobin concentration of SW at term as compared to NSW. The small modifications of oxygen affinity of SW and the increase in haemoglobin concentration at term suggest that the oxygen delivery from the maternal to the fetal blood are probably unaffected by these factors.

The excitation of mercury ammonia van der Uaals complexes allows the direct observation and characterisation of the well known exciplex in a spectroscopic manner. The complex has been formed in a supersonic expansion and excited by a laser, two electronic states were observed very deep (>5000 cm-1) and showing strikingly different behaviour. The A state is not oberved in fluorescence but dissociates into Hg(3Po) and NH3, while the other state,B fluoresces. The vibrations have been assigned in both states through isotopic substitution (ND3) as well as the electronic nature of the A and B states through rotational contours. This gives a picture of the states and their decay modes helpful to interpret the formation of the related exciplex observed in collisions of Hg 3P1 +NH3.

The controlled study presented demonstrates the results obtained when using the maximum exercise stress test (MEST) as a behavior-modification tool for coronary artery disease risk factors. Changes in attitudes, behaviors, and objective measurements of health were assessed in a low-risk population. Only exercise level was significantly altered (P less than .03). Changes in the other measured parameters were insignificant. The MEST test is also expensive, and no benefit has been demonstrated in terms of its ability to decrease the morbidity and mortality seen in coronary artery disease.

This communication is to be considered as an addendum to the reference (1). The purpose of that paper was to investigate, within the framework of geometric quantization a la Kostant — Souriau, the new notion of polarizer of a prequantizable symplectic manifold. Although that work was mainly concerned with the general scheme of compact semi-simple Lie groups, its ultimate motivation was clearly of physical nature. That is why it was there proposed to examine polarizers; a drastic selection of prequantizable coadjoint orbits showed up, which, in fact, might correspond to the actual selection of physically relevant multiplets of hadron spectroscopy. The question then arises: must one take polarizers seriously? In order to strenghthen our point of view, we propose here to discuss the properties of polarizers for spinning particles. The non relativistic Dirac particle, its Poincare invariant polarizer is explicitely worked out, as well as for the spin 1 relativistic massive particle. The associated mixed (real + Kahler) polarization naturally corresponds to the unique Poincare invariant polarization discovered by Souriau and Renouard.

The authors describe the ultrasonographic anatomy and semiology of allowing detection of the main types of fetal non-obstructive uropathies. The results of the author's personal experience in this domain are compared to data from the literature. Differential features of the uropathies are given and the limitations and practical significance of prenatal and postnatal ultrasonography are discussed.

ABSTRACT The Labrador Shelf is still at a very early stage of exploration. The various factors which make exploratory drilling particularly difficult and shorten the operating season, like ice-pack, icebergs, meteorology, are discussed. After a first unsuccessful attempt in 1971 whith a conventional anchored-type vessel, the technological breakthrough occurred when PELICAN, a dynamically positioned drillship, was successfully used in 1973 and 1974, which resulted in two gas discoveries out of three wells drilled. A description of this operation is presented as well as possible applications to other areas. 1. INTRODUCTION AND GENERALITIES The Labrador Shelf comprises an area in excess of 50,000,000 acres. It is tightly covered by federal oil and gas permits granted to 24 single. Companies and joint holder Combines. Its northern and southern boundaries are respectively the 61° parallel (which corresponds to the latitude of Hudson Strait), and the 52° parallel (Strait of Belle Isle). It is bound to the West by the Labrador Marginal Channel, fringing the mainland made up by the Canadian Precambrian Shield. To the East one can take the 1500' bathymetric contour line as a practical limit. Due to this particular situation between a channel and the continental slope there is neither shallow water nor gradual descent of the bottom from the Continent towards the oceanic depths. The "backbone" of the shelf is constituted by a succession of banks with an average water depth of 600 feet, separated by transverse topographical troughs and saddles (Figure 1). These banks are from North to South : Saglek Bank, Nain Bank, Harrison Bank, North and South Domino Banks. Their area varies from approximately 3,000,000 to 6,000,000 acres. The Eastcan Group (1) holds titles over approximately half of the Shelf, including almost the entire area of the banks. Various geophysical surveys and reconnaissance seismic work began as early as 1966 and 50,000 miles have been shot in the area since. As a result one can conclude that the Shelf is underlain by a basin in which sediments in excess of 30,000 feet at some places, have deposited. The maximum thickness is to be encountered in the North (Saglek), whereas the central and southern parts range from 5,000 to 20,000 feet. The exploratory targets are blockfaults related to rifting movements which took place when Labrador and Greenland drifted apart during Jurassic and Cretaceous times. There are a number of well-defined structures to be drilled in the years to come and the stratigraphic objectives range in age from the Paleozoic up to the Tertiary. The Labrador Shelf is at a very early stage of exploration drilling. Among three wells drilled so far, two were located on banks (Leif and Bjarni) and one in a saddle (Gudrid). To put the matter in a more regional perspective, it is interesting to recall that the most active exploratory area of Eastern Canada so far has been the Grand Banks -of Newfoundland to the East and South of the Island and the Scotian Shelf South of the Peninsula of Nova Scotia.