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Two topics are addressed in this paper. First, we discuss the variation of shapes with spin and neutron number for nuclei in the N approx. = 88 transitional region. Second, we present comments on the feeding times of very high spin single-particle yrast states.

Time-integral and time-differentialγ-γ directional correlation measurements were performed for cascades in168Er populated from the electron-capture decay of168Tm(87d). The168Tm source was dissolved in HF acid to minimize extranuclear perturbations. The results of the time-differential experiment for the 448-99.3 keV and 448-198 keV cascades showed agreement with time dependent interaction and gaveλ2(1094)=(0.79±0.09) ×107 sec−1. The attenuation factors for the 80 keV level were determined asG22 (80)=0.90±0.01 and G44(80)=0.94±0.01. OnlyI=4 spin value for the 1094 keV level is consistent with our measurements. The 632, 731, 741, and 816 keV transitions connecting theK=2+ andK = 0+ rotational bands were found to be of almost pureE2 character. The 99.3, 198, 547, 720, 830, and 1277 keV transitions are of practically pureE1 multipolarity. The 448 keVMl transition has (0.8−0.4+2.0)%E2 admixture. The results for the 1014−80keV cascade give (23±4)%E3 component in the 1014 keV transition.

Appropriate formulation of bulk parameterization of snow growth and evaporation based on observational characteristics of snow particles is presented. The parameterization is compared to that of S. A. Rutledge and P. V. Hobbs and to detailed treatment in which snow particles are assumed to grow or evaporate in each size bin separately. On the contrary to bulk parameterization of rain, snow diffusional growth or evaporation is accurately represented in the suggested bulk formulation, but growth by riming is overpredicted. Integrations of water budget equations in a one-dimensional updraft have shown that quantitative results, e.g., precipitation intensity, cloudwater content, supersaturation with respect to ice, depend on the parameterization scheme employed, which suggests that comparisons of field measurements with parameterized model outputs is usually not straightforward.

Lifetime measurements for the isotopes 155 Dy and 156 Dy have been extended up to spins around 40ħ by the Doppler shift attenuation method in conjunction with γ-γ-coincidence measurements. Results have been obtained for the yrast band in 156 Dy and for three bands in 155 Dy. Strong retardations of the E2-strengt were observed for intruding terminating sequences, for which specific single particle configurations are suggested.

The excitation spectra of phosphorus, arsenic, isolated interstitial lithium, and lithium oxygen donors in silicon have been investigated under the high resolution of a Fourier-transform spectrometer. Using a "strain-free" mounting technique, the linewidths are observed to be much narrower than those reported earlier in the literature; the observed linewidths appear to be limited by the "lifetime" effects. The linewidths and shapes of the excitation lines of phosphorus donors in silicon, introduced by the nuclear transmutation of $^{30}\mathrm{Si}$ into $^{31}\mathrm{P}$ by the capture of a slow neutron followed by a ${\ensuremath{\beta}}^{\ensuremath{-}}$ decay, are studied; the influence of the charged defects produced by neutron irradiation is demonstrated and explained in terms of the electric fields due to charged impurities and defects.

Plane-wave Born approximation calculations have been carried out for the (p,d) reaction at intermediate beam energies with the purpose of elucidating the manner in which the various physical parameters of the problem determine the behaviour of the cross-sections. Analytical formulae for the differential cross section are derived for three choices of the bound state wave function: square well, Woods–Saxon, and truncated harmonic oscillator. The formulae can essentially be factored into two parts, one which oscillates rapidly with momentum transfer q(and is not physically important) and the other which varies smoothly with q and describes the 'envelope' of the calculated angular distribution. For the square well and truncated harmonic oscillator form factors, this envelope function varies as q−8 and q−10 respectively, but in the Woods–Saxon case it is given predominantly by an exponential q-dependence. To illustrate our main points, calculations are presented for the 208Pb(p,d) reaction, primarily at 200 MeV, as well as normalized fits to presently available data at 185 MeV on light and intermediate mass nuclei and at 700 MeV on 12C. The envelope dependence of the square well and Woods–Saxon form factors gives a reasonably good account of these data.

Summary and conclusions Analysis was made of crystalline form and size distribution of powdered minerals related to talc. The stability of a talc-iodine mixture was investigated by solubility studies. Biologic effects of minerals in the pleural and peritoneal cavities of rats and dogs were studied. 1. The crystalline structure of talcose minerals is heterogeneous. 2. A specimen of talc supplied for poudrage contained only 12 per cent mineral. 3. The talc-iodine combination is almost immediately disrupted on incubation in vitro. 4. Production of pleural adhesions in these animals was inconstant. 5. Substances for poudrage should be analyzed so that standard mixtures can be used and compared. 6. Disruption of the visceral pleura is probably essential to any consistent therapeutic effect. 7. End results of talc poudrage should be reported in terms of results in a treatment group compared with matched controls. 8. Powdered silica is a pure mineral that may be capable of eliciting a standard and intense chemical inflammatory response. Mr. Joseph A. Houghton, Director of the Industrial Chemical Service, Liberty Mutual Insurance Company, Boston, kindly performed the dispersion-staining and microscopic identification of the elutriated talc.

The amplitude mixing ratios of the E2 to M1 and E0 to E2 components of the 2 + (793 keV) 2 + transition in 184 W were obtained from γγ, and gamma-conversion electron angular correlation measurements. The γγ measurements used a Ge(Li) detector in some cases; the eγ correlations were performed using a magnetic lens spectrometer. The results obtained are δ (E2:M1) = + 18.7 +4.6 −3.1 + 0.38 ≧ q( E 0: E 2) ≧ − 0.28 for + 53 ≧ λ ≧ − 113 . Agreement with Kumar's theoretical values for δ and q is contradictory: the former favours a 2″ assignment, the latter a 2prime; assignment to the 904 keV level.

$\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ directional correlation and polarization directional correlation experiments were performed on three cascades in $^{96}\mathrm{Mo}$ populated from $^{96}\mathrm{Tc}$ (4.3 day). Ge(Li) detectors were used in both spectrometers. Combination of the results give unique spin-${4}^{+}$ assignment to the 1628-keV level and spin-${6}^{+}$ assignments to both the 2441- and 2755-keV levels in $^{96}\mathrm{Mo}$.

$\frac{E2}{M1}$ mixing ratios of the 709-, 714-, and 723-keV transitions in ${\mathrm{Te}}^{124}$, the 754-keV transition in ${\mathrm{Te}}^{126}$, and the 491-keV transition in ${\mathrm{Xe}}^{126}$ were measured using the $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ directional-correlation technique. In addition, the measurements on the 646-603-keV, 1691-603-keV, and 2091-603-keV $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ cascades in ${\mathrm{Te}}^{124}$ are in agreement with pure $E2$ character of the 1691- and 2091-keV transitions in ${\mathrm{Te}}^{124}$. Coaxial Ge(Li) and Na(Tl) scintillation detectors were used in different combinations depending on the energy resolution required for a particular measurement. The results for the mixing ratios are $\ensuremath{\delta}(709)={+0.04}_{\ensuremath{-}0.05}^{+0.03}$, $\ensuremath{\delta}(714)=+0.98\ifmmode\pm\else\textpm\fi{}0.19$, and $\ensuremath{\delta}(723)=\ensuremath{-}3.4\ifmmode\pm\else\textpm\fi{}0.1$ for the transitions in ${\mathrm{Te}}^{124}$; $\ensuremath{\delta}(754)={\ensuremath{-}5.5}_{\ensuremath{-}0.3}^{+0.4}$ for the ${2}^{{+}^{\ensuremath{'}}}\ensuremath{\rightarrow}{2}^{+}$ transition in ${\mathrm{Te}}^{126}$; and $\ensuremath{\delta}(491)={+27}_{\ensuremath{-}9}^{+30}$ for the ${2}^{{+}^{\ensuremath{'}}}\ensuremath{\rightarrow}{2}^{+}$ transition in ${\mathrm{Xe}}^{126}$. There is an indication that the mixing ratios for the ${2}^{{+}^{\ensuremath{'}}}\ensuremath{\rightarrow}{2}^{+}$ transitions in even-even tellerium isotopes are negative and the mixing ratios of similar transitions in even-even Xe isotopes have positive values.

Higher order effects in allowed $\ensuremath{\beta}$ transitions may be generated by the interference of the allowed Gamow-Teller components with second-forbidden components. In strongly hindered $\ensuremath{\beta}$ transitions, this interference effect is expected to give rise to $\ensuremath{\beta}\ensuremath{-}\ensuremath{\gamma}$ directional correlations with measurable anisotropies. The $\ensuremath{\beta}\ensuremath{-}\ensuremath{\gamma}$ directional correlations of the hindered allowed $\ensuremath{\beta}$ transition ($log\mathrm{ft}g8$) in the deformed nuclei ${\mathrm{Eu}}^{152}$, ${\mathrm{Eu}}^{154}$, and ${\mathrm{Tb}}^{160}$ were studied. The $\ensuremath{\beta}$-correlation factor $A_{2}^{}{}_{}{}^{\ensuremath{\beta}}$, which characterizes the $\ensuremath{\beta}$ transition in the expression for the $\ensuremath{\beta}\ensuremath{-}\ensuremath{\gamma}$ directional correlation $W(\ensuremath{\theta})=1+A_{2}^{}{}_{}{}^{\ensuremath{\beta}}A_{2}^{}{}_{}{}^{\ensuremath{\gamma}}{P}_{2}(cos\ensuremath{\theta})$, was found to be vanishingly small in all cases, except that of ${\mathrm{Tb}}^{160}$. The results are: $A_{2}^{}{}_{}{}^{\ensuremath{\beta}}=\ensuremath{-}0.017\ifmmode\pm\else\textpm\fi{}0.012$ for the 0.70-MeV $\ensuremath{\beta}$ transition of ${\mathrm{Eu}}^{152}(logft=10.6)$; $A_{2}^{}{}_{}{}^{\ensuremath{\beta}}=+0.016\ifmmode\pm\else\textpm\fi{}0.020$ for the 0.20-MeV $\ensuremath{\beta}$ transition of ${\mathrm{Eu}}^{152}(logft=9.6)$; $A_{2}^{}{}_{}{}^{\ensuremath{\beta}}=0.007\ifmmode\pm\else\textpm\fi{}0.006$ for the 0.58-MeV $\ensuremath{\beta}$ transition of ${\mathrm{Eu}}^{154}(logft=10.0)$; and $A_{2}^{}{}_{}{}^{\ensuremath{\beta}}=+0.041\ifmmode\pm\else\textpm\fi{}0.015$ for the 0.566-MeV $\ensuremath{\beta}$ transition of ${\mathrm{Tb}}^{160}(logft=8.1)$. A summary of $\ensuremath{\beta}\ensuremath{-}\ensuremath{\gamma}$ directional correlation measurements on allowed $\ensuremath{\beta}$ transitions is presented and the implications of the results are discussed. In most cases the experimental results suggest that the effects that cause the reduction of the allowed matrix elements are also operative in reducing the second-forbidden matrix elements.

The ion-implantation-perturbed-angular-correlation technique has been used to measure the $g$ factors of the first ${2}^{+}$ excited states of four even osmium nuclei in a ferromagnetic nickel host. The observed angular precessions were: $\ensuremath{\omega}\ensuremath{\tau}(^{192}\mathrm{Os})=0.22\ifmmode\pm\else\textpm\fi{}0.01$, $\ensuremath{\omega}\ensuremath{\tau}(^{190}\mathrm{Os})=0.277\ifmmode\pm\else\textpm\fi{}0.009$, $\ensuremath{\omega}\ensuremath{\tau}(^{188}\mathrm{Os})=0.39\ifmmode\pm\else\textpm\fi{}0.03$, and $\ensuremath{\omega}\ensuremath{\tau}(^{186}\mathrm{Os})=0.38\ifmmode\pm\else\textpm\fi{}0.08$. The angular precession result for $^{192}\mathrm{Os}$ is in excellent agreement with the results of perturbed-angular-correlation measurements in nickel using radioactive sources. It was found that the internal field seen by the osmium nuclei implanted in nickel is in good agreement with the value obtained by room temperature NMR techniques. The available direct lifetime measurements for $^{186,188}\mathrm{Os}$ and lifetimes extracted from $B(E2)$ values for $^{190,192}\mathrm{Os}$ are used to obtain the gyromagnetic ratios: $g(^{192}\mathrm{Os})=0.39\ifmmode\pm\else\textpm\fi{}0.03$, $g(^{190}\mathrm{Os})=0.39\ifmmode\pm\else\textpm\fi{}0.03$, $g(^{188}\mathrm{Os})=0.29\ifmmode\pm\else\textpm\fi{}0.03$, and $g(^{186}\mathrm{Os})=0.24\ifmmode\pm\else\textpm\fi{}0.05$.

Cloud-scale models apply two drastically different methods to represent condensation of water vapor to form and grow cloud droplets. Maintenance of water saturation inside liquid clouds is assumed in the computationally efficient saturation adjustment approach used in most bulk microphysics schemes. When super- or subsaturations are allowed, condensation/evaporation can be calculated using the predicted saturation ratio and (either predicted or prescribed) mean droplet radius and concentration. The study investigates differences between simulations of deep unorganized convection applying a saturation adjustment condensation scheme (SADJ) and a scheme with supersaturation prediction (SPRE). A double-moment microphysics scheme with CCN activation parameterized as a function of the local vertical velocity is applied to compare cloud fields simulated applying SPRE and SADJ. Clean CCN conditions are assumed to demonstrate upper limits of the SPRE and SADJ difference. Microphysical piggybacking is used to extract the impacts with confidence. Results show a significant impact on deep convection dynamics, with SADJ featuring more cloud buoyancy and thus stronger updrafts. This leads to around a 3% increase of the surface rain accumulation in SADJ. Upper-tropospheric anvil cloud fractions are much larger in SPRE than in SADJ because of the higher ice concentrations and thus longer residence times of anvil particles in SPRE, as demonstrated by sensitivity tests. Higher ice concentrations in SPRE come from significantly larger ice supersaturations in strong convective updrafts that feature water supersaturations of several percent.

This paper investigates spectral broadening of droplet size distributions through a mechanism referred to as the eddy hopping. The key idea, suggested a quarter century ago, is that droplets arriving at a given location within a turbulent cloud follow different trajectories and thus experience different growth histories and that this leads to a significant spectral broadening. In this study, the adiabatic parcel model with superdroplets is used to contrast droplet growth with and without turbulence. Turbulence inside the parcel is described by two parameters: (i) the dissipation rate of the turbulent kinetic energy ε and (ii) the linear extent of the parcel L. As expected, an adiabatic parcel without turbulence produces extremely narrow droplet spectra. In the turbulent parcel, a stochastic scheme is used to account for vertical velocity fluctuations that lead to local supersaturation fluctuations for each superdroplet. These fluctuations mimic the impact of droplets hopping turbulent eddies in a natural cloud. For L smaller than a few meters, noticeable spectral broadening is possible only for strong turbulence—say, ε > 100 cm2 s−3. For L typical for grid lengths of large-eddy simulation (LES) models (say, L between 10 and 100 m), the impact is significant even with relatively modest turbulence intensities. The impact increases with both L and ε. The representation of eddy hopping developed in this paper can be included in a straightforward way in the subgrid-scale scheme of a Lagrangian LES cloud model and may lead to a significant acceleration of simulated rain development through collision–coalescence.

Since inactivated vaccines have proved disappointing in preventing Mycoplasma pneumoniae disease, we have initiated studies to identify protective immunogens as candidates for an acellular, purified component vaccine. A cell-free extract was prepared, and was shown to have hemagglutination, attachment inhibition, and ciliostasis activities. Ciliostatic activity in hamster tracheal organ cultures was dependent on the time of incubation and on the amount of added extract. The ciliostatic factor was resistant to boiling and to trypsin and chymotrypsin digestion. When administered intratracheally to Golden Syrian hamsters, the extract induced lung lesions with histopathologic characteristics similar to those caused by virulent M. pneumoniae infection. Thus, in addition to attachment and ciliostatic factors, the extract contains factors that induce inflammatory responses in hamster lungs and cause cytotoxic damage to lung tissues.

A review of seven carotid body tumors less than 5 cm in diameter confirms the thesis of other recent reports that such tumors can be resected with minimal morbidity. In two of our cases, initial exploration and biopsy were performed not suspecting the nature of the neck mass; in one of these, hypoglossal and facial nerve deficits resulted. Angiography was diagnostic in six of our seven cases and should be used to establish the diagnosis preoperatively in any neck mass of doubtful origin where carotid body tumor is a part of the differential diagnosis.

In 1956, Robinson and colleagues (1) reported the first isolation of a mycoplasma from a contaminated cell culture. Subsequently, mycoplasmas have been shown to be common and bothersome contaminants capable of altering the activity of cells and affecting the results of study. Because many of the vaccines prepared for human use are produced in cell cultures and are subject to mycoplasma contamination, the Bureau of Biologics has maintained a continuing study for the past 18 years to examine various aspects of mycoplasma contamination. This report will review some of our findings and present a brief, updated status report on the incidence, prevalence and sources of mycoplasma contamination. The subject has been reviewed in detail elsewhere (2–5).

The level scheme of 148Gd has been extended to I=44 by use of a Compton-suppressed Ge spectrometer array. Up to I=38 the observed level spectrum consists of spherical and oblate states of aligned-particle type. A change in structure along the yrast line is indicated at higher spins, where fast E2 transitions suggest the onset of collectivity.

Clinical isolates, cell-culture contaminants, and the type strain PG21 of Mycoplasma hominis were examined for attachment to erythrocytes and human cell cultures. Strain 13428 (from blood, postpartum fever) and strain 1184 (cell culture) attached to human and guinea pig erythrocytes, but there were no differences in attachment activities between these strains. However, five M. hominis strains isolated from different tissue sites showed quantitative differences in attachment to human WiDr (intestinal carcinoma cell cultures), MRC-5 (human embryonic lung fibroblasts) and HeLa (carcinoma of cervix) cell cultures. The relative attachment activities were, in descending order: strain 1184 (cell culture), strain 11932 (cervix), strain 13428 (blood, postpartum fever), 13408 (nongonococcal urethritis), and type strain PG21 (multiple passage, originally from human rectum). Trypsin and pronase treatment of M. hominis strain 1184 markedly reduced attachment, suggesting that surface proteins play a role in M. hominis attachment to mammalian cells. In subsequent studies, strain 1620 (septic arthritis) showed the highest attachment activity, whereas strain 1652 (surgical skin flap) and L01888 (cell culture) showed attachment activity similar to cell culture strain 1184. The differing attachment activities of these M. hominis strains isolated from different infected sites of patients with a variety of diseases may be relevant to the virulence of these strains.

As far as we know, humans are the only known natural hosts for M. pneumoniae disease. Whereas volunteer studies have provided useful data on the pathogenesis of disease and efficacy of vaccines, experimentally inducing disease in humans raises serious ethical questions and has become increasingly difficult to defend. Thus, there is a genuine need for a satisfactory animal model to study M. pneumoniae disease. Using the cotton rat and developing chick embryo models, Eaton and co-workers (9-13) have clearly shown that the infectious "Eaton agent" was the cause of primary atypical pneumonia. After the causative agent was identified as M. pneumoniae (14), more definite and quantitative studies were possible. The hamster animal model has provided most of our information on the pathogenicity of strains, the pathogenesis of disease and the potency of inactivated vaccines. However, protective data obtained in hamsters immunized with the TS mutant vaccines did not correlate with data obtained in humans, raising concern regarding the use of the hamster animal model to evaluate the potency of live TS vaccines. The chimpanzee animal model has a number of advantages. Chimpanzees become clinically ill, show positive X-ray findings, and develop cold agglutinin titers. In fact, the experimentally induced disease in chimpanzees is remarkably similar to naturally occurring primary atypical pneumonia in patients. Because of the close genomic relationship, immunologic reagents prepared and used for human studies can also be used successfully in chimpanzee studies. The chimpanzee model also has some serious disadvantages. They are expensive to house and maintain and are generally not available to the scientific community. Nonetheless, chimpanzees are probably the best, most meaningful animal models established thus far to examine the infectious process, the immune response and the pathogenesis of this disease and to determine approaches to effective therapy and immunization of diseases produced by known pathogens, like M. pneumoniae, as well as reputed mycoplasma pathogens, such as M. genitalium and M. hominis.

1 In spontaneously active Purkinje fibres of young cows the dose-response curves of the action of isoprenaline upon different electrophysiological parameters were measured. 2 The increase in slope of diastolic depolarization could roughly be described by a one-for-one binding curve with a half maximum effect near 10−8m and the increase in the height of the plateau level by a two-for-one binding curve with a half maximum effect near 10−7m (—)-isoprenaline. 3 These dose-response curves were similar to those of two parameters measured under voltage clamp conditions by other authors. The increase in slope of diastolic depolarization behaved like the shift of the activation curve for the pacemaker potassium current towards positive potentials and the growth in plateau height like the increase in the slow inward current mainly carried by Ca ions. From this conformity we propose that the parameters evaluated by us from action potential records could be used for a qualitative analysis of the action of catecholamines on pacemaker potassium current and Ca influx. 4 The effects of the isomers of a new drug, 1-isopropylamino-3(4′hydroxyphenoxy)-propan-2-ol (IHP), were evaluated in the same way as those of isoprenaline. The (—)-isomer was at optimal concentrations (10−5m) nearly half as effective as isoprenaline in increasing frequency and slope of diastolic depolarization but caused no increase in plateau height. An identical relationship, but at 5 to 10 times higher concentrations, was obtained with the (+)-isomer. 5 When 10−4m(—)-IHP was added to a preparation equilibrated with a maximum dose of (-)-iso-prenaline (10−6m), frequency and plateau height declined. This result together with the observation that the effects of IHP could be blocked by the specific β-antagonist propranolol, revealed the jff-agonistic nature of the new drug. Its inefficiency in increasing the plateau height and thus the slow (Ca) inward current was explained by its relatively low potency and intrinsic activity.

Strains of Mycoplasma hominis isolated from different tissues of patients with a variety of disease processes and from cell culture substrates show marked phenotypic and genotypic heterogeneity, as determined by their antigenic and isozyme properties and by [3H]DNA-DNA hybridization and DNA cleavage pattern analyses. Strains isolated from the same tissues (blood of postpartum patients or human urogenital tract or cell culture substrates) have very high genomic homology and form clusters of similar strains. Clusters of strains that colonize similar specialized urogenital tissues may initiate diseases that reflect damage to the particular tissue colonized. Antigenic markers such as those for attachment components for different strain clusters may help determine the role, if any, played by strain differences in the etiology of a family of urogenital diseases.

Die Verwendungsmoglichkeiten der Kohlefaser als implantierbares Biomaterial ist seit den 70er Jahren bekannt. Im Vordergrund steht hier die Verstarkung bzw. der Ersatz von Sehnen- und Bandstrukturen sowie die Konsolidierung von Verbundwerkstoffen.

The evolution of a technique of inguinal hernia repair, progressively incorporating more modern materials and concepts, is described and evaluated. Anatomic precepts of hernia anatomy put forth by Condon form the foundation of this technique. The Shouldice methodology dominates the original plan of patient management but more modern suture materials and local anesthetics afford even greater ease and efficiency to this hernia repair plan. The results of 421 herniorrhaphies done by the primary author over ten years are reported with three patients lost during follow-up (0.7%). No cases are included unless a minimum of three years since surgery has elapsed. The unselected recurrence rate is 2.77 per cent. All ten recurrences are studied and related to changes in surgical technique. Cost effectiveness goals such as early discharge and same-day surgery are also discussed as they apply to this approach.

1. When cardiac preparations are rewarmed following prolonged hypothermia a transient hyperpolarization occurs in K-containing media. This hyperpolarization is correlated with the active Na efflux. It might be due to electrogenic Na pumping or to extracellular K depletion brought about by the activity of an electroneutral Na-K exchange pump. In order to distinguish between these mechanisms the effect of various extracellular K concentrations ([K](o)) on the membrane potential of guineapig atria was studied before and after hypothermia.2. The membrane potential increased with decreasing [K](o) before cooling. It reached values of -64 and -92 mV at 10.8 and 0 mM-K, respectively.3. The membrane hyperpolarized transiently after hypothermia beyong the potential observed before cooling. Maximal values of about -94 mV were obtained during rewarming in solutions containing 0.4-2.7 mM-K. The membrane potential was significantly lower (-88 mV) in K-free media. It was also diminished at [K](o) higher than 2.7 mM and was measured to be -74 mV at 10.8 mM-K.4. The hyperpolarization of the cell membrane during the first 20 min of rewarming was maximal at 2.7 mM-K and yielded 15.5 mV. The hyperpolarization amounted to 7.2 and 10 mV at 0.4 and 10.8 mM-K, respectively. No hyperpolarization occurred in K-free solutions.5. The rate of decline of the transient hyperpolarization increased with [K](o).6. Variations of membrane input resistance after changes in [K](o) were measured in rewarmed atrial trabecula. The measurements revealed an increase in membrane resistance in lower [K](o).7. It is concluded that the transient hyperpolarization of the cardiac cell membrane during rewarming is due to the activation of an electrogenic Na pump.8. The (relative) strength of the pump current at various [K](o) was derived from the observed dependence of the hyperpolarization and of the membrane input resistance on [K](o). The current is estimated to be half-maximal at about 1.5 mM-K.

The levels of 124Te have recently been reinvestigated by Auer et al.1 ) and Meyer et al.2 ) from the decay of 124 Sb and by Ragaini et al.3 ) from the decay of 124I. The low excited states of 124Te exhibit a ‘vibrational’ pattern which could be expected for this nucleus (proton number 52 and neutron number differing by only 10 from the closed neutron shell). The measurements of Warner and Draper4) show, however, that the 4+ level at 1249 keV could also be considered as a member of the ground state quasi — rotational band. The 723 keV transition proceeds between the first and the second excited 2+ levels which would correspond to one and two phonon excitation respectively in the vibrational picture. The results of the measurements of the mixing ratio, δ723, for this transition are conflicting. From our previous measurements6) of β-γ directional correlation in the decay of 124 Sb we were able to calculate the mixing ratio of the 723 keV gamma transition. This measurement gave — 2.8 ≤δ723 ≤ −1.0. The β-γ directional correlation measurement by Paul7) was not precise enough to distinguish between δ723 — values in the region −5.0 ≤δ723 ≤ −0.7. There is a mistake in the interpretation of the 1368γ — (723γ) — 603γ directional correlation result obtained by Lindquist and Marklund8). Their experimental value, A22 = −0.027 ± 0.008, measured for this cascade gives 0.45 ≤ ∣δ723 ∣ ≤ 0.70 and not ∣δ∣ ≈ 1, as stated in their paper. The above mentioned results are less precise than the value δ723 = −4.1 ± 0.6 obtained by Glaubman and Oberholtzer9) from the β-γ-γ directional correlation measurement. The γ-γ measurements by Dorikens-Vanpraet et al.10) performed with scintillation detectors involve large corrections due to unresolved cascades. They favour δ723 ≈ −2,4.