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At about 470°C, H2S increases the initial rate of cis-3-methyl-2-pentene decomposition into methane and isoprene but diminishes that of isomerization into 2,3-dimethyl-1-butene; it also causes cis-trans isomerization of the olefin. A free-radical chain mechanism is proposed to interpret the experimental facts.

The authors report on a new AID-like algorithm that overcomes some of the conceptual problems involved in using AID for consumer segmentation. Using a simple cost-profit formulation they segment 356 women consumers on the basis of 26 dimensions.

The influence of metastable and short-lived excited states produced by electron-bombardment of atoms in the discharge plasma of ion engines using the rare gases has been considered. Theoretical Gryzinski cross sections were used to investigate the effects of collisions on the excited states of the atoms. It was found that metastable atoms are rapidly excited to higher states from which ground-state transition is allowed, because of the large cross sections for this excitation, and that predicted electron energy losses due to atomic excitation collisions gave good agreement with experiment in the case of argon, krypton and xenon. Operation with neon, however, was anomalous.

Three adult male stutterers spoke spontaneously during a series of base-rate and noise sessions. Base rate was run first for a minimum of 100 minutes and until two criteria of stability were met. Following base rate, all subjects were presented binaurally with a 100 dB SPL white noise for a minimum of 100 minutes. One subject also was tested under 80 dB SPL noise and 60 dB SPL noise. All subjects decreased their stuttering frequencies during the first five-minute period in which the 100-dB noise was presented. Over longer periods of time under 100 dB, one subject increased his frequency of stuttering slightly, and one subject decreased his frequency of stuttering slightly. The third subject’s frequency of stuttering decreased significantly under 100 and 80 dB, but not under 60 dB. It appears that the effects of short- and long-term noise on stuttering are not the same.

Cultures of the clonally derived pluripotent teratocarcinoma cell line, SIKR, are heterogeneous. They are characterized by the presence of two cell types—the "C cells", which grow as tight, round colonies on a monolayer of the morphologically distinct "E cells". In contrast to the C cells, whose proliferation is apparently uninhibited by high cell density, the E cells show density-dependent inhibition of growth. Subclones of SIKR are of two types: they are either similar to the parent culture, in that they contain both C and E cells (CE subclones) and are themselves tumorigenic and pluripotent; or they are composed only of E cells (E-type subclones), which are primarily not tumorigenic, but may become so after spontaneous transformation in vitro. The tumors formed by transformed E cells (E-t cells) are monotypic ("fibroblastic"), consisting of one cell type which is not clearly identifiable, but which is distinctly not embryonal carcinoma. It is concluded that the tumorigenic C cells are the stem cells of this teratocarcinoma line, and that they give rise to nontumorigenic E cells in vitro, but that the reverse does not occur. It is suggested that the C to E transition represents cell determination in vitro. The interest of this cell culture system for both developmental and oncological studies is discussed.

The Deutsche Forschung sqemenschaft and study of airport noise is reviewed, some further results are included. The study, which considered sociological, psychological and physiological impacts, also describes statistical and analytical methods.

Peritoneal exudate macrophages, when exposed to bacterial lipopolysaccharide in culture, were found to produce collagenase (EC 3.4.24.3). This enzyme was not detected in extracts of the macrophages or in media from nonstimulated macrophage cultures. Lipidcontaining fractions of the lipopolysaccharide, including a glycolipid from the rough mutant of Salmonella minnesota (R595) and lipid A, were potent stimulators of collagenase production. The lipid-free polysaccharide fraction had no effect. Cycloheximide prevented the production of collagenase by endotoxin-treated macrophages, suggesting that it was newly synthesized.

The dynamic mechanical relaxation behavior of two series of amorphous polyolefins, was investigated from 4.2 K to the glass transition. Most of the polymers show a damping maximum or plateau in the 40 to 50 K region. Various mechanisms which have been suggested for cryogenic relaxations in amorphous polymers are considered as they might relate to the polyolefins. Two secondary relaxation processes above 80 K are distinguished. A relaxation at about 160 K (beta) in the second and third member of each series is associated with restricted blackbone motion. This process requires a certain degree of chain flexibility since it is not observed in the first member of each series. A lower temperature process (gamma) is observed in each member of the second series and is attributed to motion of the ethyl side group.

We measured regional lung volumes from apex to base in humans during changes in thoracoabdominal shape which we monitored with magnetometers. In erect subjects, voluntary changes of shape at FRC did not change regional volume distribution. In supine subjects, the effect of negative pressure applied to the abdomen and a similar thoracoabdominal configuration achieved by voluntary means were studied. The distribution of regional volumes in both situations was the same as that measured during relaxation at the same overall lung volumes. We concluded that neither voluntary changes in shape nor negative abdominal pressure influenced the human pleural pressure gradient. This result, which differed from findings in animals, was probably because the human chest was relatively stiff and behaved with one degree of freedom; all parts of the human rib cage changed dimensions proportionally while negative abdominal pressure distorted the rib cage of animals.

Angular distributions for elastic and inelastic scattering have been measured on six analog resonances in the $^{130}\mathrm{Te}$+p system and at two off resonance energies. Partial widths are deduced from the angular distributions. Formulae for the spectroscopic amplitudes within the framework of the quasiparticle random phase approximation are presented. The experimental results are compared with the theoretical predictions.[NUCLEAR REACTIONS $^{130}\mathrm{Te}$(p,p\ensuremath{'}), $E=7.5\ensuremath{-}14$ MeV; enriched targets, measured $\ensuremath{\sigma}({E}_{\mathrm{p}},\ensuremath{\theta})$; deduced spectroscopic amplitudes; $^{131}\mathrm{Te}$ calculated and spectroscopic amplitudes predicted.]

The adducts of BI3 and BBr3 with various tertiary phosphines and their chalcogenide derivatives are described. The proton and boron-11 NMR spectra of many of these compounds are reported for the first time. Although the methyl proton-phosphorus-31 coupling constants are nearly identical in the (CH3)3PBX3 (X = F, Cl, Br, I) series, the boron-phosphorus coupling constant, JBP, is anomalously low for (CH3)3PBI3 (116 Hz) relative to other members of the series. The phosphine adducts of BBr3 and BI3 are white, air and water insensitive solids, whereas the phosphine chalcogenide adducts are quite moisture sensitive. The BI3 adducts with phosphine chalcogenides lose iodine fairly readily to form intractable material.

Two sibs with the Ehlers-Danlos syndrome, one of whom was shown to have hydroxylysine-deficient collagen, are described. In addition to the usual features of the Ehlers-Danlos syndrome (loose-jointedness and excessively stretchable, fragile, and bruisable skin), these patients had severe scoliosis and fragility of ocular tissues leading to rupture of the globe or retinal detachment. This combination of symptoms was tentatively classified as Ehlers-Danlos syndrome, Type VI. The condition is inherited as an autosomal recessive. The activity of lysyl hydroxylase was present at a reduced level in fibroblasts cultured from the patient's skin.

The clinical and biochemical effects of 20 and 50 mcg/day ethinyl estradiol (EE) and .625 and 1.25 mg/day conjugated equine estrogens (Premarin) administered in random sequence for 3 months were studied in 17 oophorectomized women. Patient preference for either of the treatments was about equal. Serum cholesterol clot lysis time plasma fibrinogen platelet adhesiveness and activated partial thromboplastin time were not significantly changed with either regimen (p greater than .05). Both doses of EE caused a significant increase in serum triglyceride levels (p less than .02) though no significant change occurred with Premarin (p greater than .05). EE decreased serum luteinizing hormone levels to a considerably greater degree than Premarin though levels were still higher than those of normal premenopausal women. Thus the increase in serum triglyceride levels cannot be attributed to the estrogenic potency of the EE doses employed.

The sysems PCl3BF3, PCl3BCl3, CH3PCl2BF3, CH3PCl2BCl3, (CH3)2PClBF3, (CH3)2PClBCl3, (CH3)3PBF3 and (CH3)3PBCl3 are reported. Three components were not available commercially and were prepared by improved syntheses, i.e. (CH3)3P, (CH3)2PCl and CH3PCl2. No evidence was found for the existence of the reported compounds PCl3.BF3 or PCl3.BCl3. With CH3PCl2 it was found that BF3 did not form an adduct whereas it was confirmed that BCl3 forms CH3PCl2.BCl3. The systems with (CH3)2PCl furnished evidence for [(CH3)2PCl]2.BF3 and confirmed the existence of (CH3)2PCl.BCl3. The existence of the previously reported (CH3)3P.BF3 and (CH3)3P.BCl3 was confirmed also. These systems were studied and characterized by tensimetric titrations, direct addition syntheses, 11B NMR, and 1H NMR spectra, melting point determinations and vapor pressure data. A basicity trend for the phosphorus compounds was found with BCl3 to be (CH3)3P>(CH3)2PCl>CH3PCl2.

The idea of using electrosensitive fluid for fluid power control is not new. However, most of the available information is of an experimental nature. This paper presents an attempt to model the behaviour of an insulating fluid containing concentrations of small dielectric particles. Results of this analysis show that the pressure required to push the mixture between parallel plates is proportional to the square of the applied voltage. The model also indicates that the performance of the mixture is dependent on particle size and concentration of solids. Reasonable, good experimental evidence is included to support these conclusions.

Erythromycin A is slowly metabolized to a new antibiotic, erythromycin E (5), when incubated with fermentations of certain strains of the producing organism Streptomyces erythreus. Erythromycin E contains a novel ortho ester grouping not previously encountered in macrolide antibiotics. The isolation of erythromycin E extends and further delineates the latter stages of the erythromycin biogenetic pathway.

Thyrotropin releasing hormone (TRH) antagonizes the behavioral and temperature reducing effects of pentobarbital in rodents. The hormone is effective whether given before or after the barbiturate. This antagonism by TRH of the effects of pentobarbital probably does not depend upon thyroid hormone release as L-triiodothyronine administration is ineffective.