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Muon-spin-relaxation measurements have been performed on a high-Tc superconductor La(1.85)Sr(0.15)CuO4. In an external transverse magnetic field of 500 G, a magnetic field penetration depth of 2000 A at T = 10 K has been determined from the muon-spin-relaxation rate which increased with decreasing temperature below Tc. From this depth and the Pauli susceptibility, the superconducting carrier density is estimated at 3 x 10 to the 21st per cu cm. The zero-field relaxation rates above and below Tc were equal, which suggests that the superconducting state in this sample is not associated with detectable static magnetic ordering.

This report reviews the experimental investigation of high energy e + e − interactions by the MARK J collaboration at PETRA, the electron-positron colliding beam accelerator at DESY in Hamburg, Germany. The physics objectives include studies of several purely electromagnetic processes and hadronic final states, which further our knowledge of the nature of the fundamental constituents and of their strong, electromagnetic and weak interactions. Before discussing the physics results, the main features and the principal components of the MARK J detector are discussed in terms of design, function, and performance. Several aspects of the on-line data collection and the off-line analysis are also outlined. Results are presented on tests of quantum electrodynamics using e + e − → e + e − , μ + μ − and τ + τ − , on the measurement of R , the ratio of the hadronic to the point-like muon pair cross section, on the search for new quark flavors, on the discovery of three jet events arising from the radiation of hard noncollinear gluons as predicted by quantum chromodynamics, and on the determination of the strong coupling constant α s .

7 alpha-Bis (beta-chloroethyl)amino-methyl-6,14-endoethenotetrahydrooripavine (alpha-CAM) was found to bind to opioid receptors irreversibly and react directly with sulfhydryl (SH) groups in P2 preparations of rat brain. The P2 preparations were pretreated as follows: protection of the SH groups at the opioid receptor binding sites by morphine or etorphine, and inactivation of the SH groups outside the binding sites by N-ethylmaleimide (NEM), followed by removal of the morphine or etorphine by washing. alpha-CAM was still able to bind the pretreated P2 preparations in an irreversible manner. The results indicate that the formation of covalent bonds between alpha-CAM and the SH groups of opioid receptor binding sites is possibly one of the biochemical mechanisms of the irreversible action of alpha-CAM.

7 alpha-bis (beta-chloroethyl) aminomethyl-6, 14-endoetheno-tetrahydro oripavine (alpha-CAM) is a new irreversible opioid receptor agonist. Its effect on isolated tissues (guinea pig ileum, mouse vas deferens, rat vas deferens and rabbit vas deferens) were studied. It was shown to be bound irreversibly to rat brain P2 membrane preparations. The ED50 of its analgesic effect in mice (icv) was found to be 0.12 nmol/mouse, and the effect may last as long as 2-3 days. It is a compound which produces the longest analgesia known up to date. A single dose (icv) of alpha-CAM was sufficient to produce dependence in mice. Thus, the compound may serve as an agent for studying the mechanism of physical dependence.

A study of hard tissue and soft tissue contour and growth on normal occlusion among Chinese population was made by means of computerized radiographic cephalometrics. Correlation analysis and polygon methods were applied to analyse the profile contour. The result showed that the dento-skeletal pattern and integumental contour were not necessarily alike, the diversity could be quite prominent. As to the growth change features in soft-tissue and hard-tissue structure, we found that the growth behavior of the lips seemed to show a tendency to follow the dental structure directly. The bony profile tended to become less convex with aging, while the soft-tissue profile remained stable in its degree of convexity.

The AGS proton synchrotron at Brookhaven National Laboratory facilitates a medium-intensity polarized muon channel. Muon spin relaxation (μSR) experiments on single-phase specimens of (La1.85Sr0.15)CuO4 and YBa2Cu3O7 have been carried out at this facility field (500 – 1000 G) applied perpendicular to the initial muon spin direction, the magnetic-field penetration depth λ in the superconducting state has been determined.

BACKGROUND: Elevated levels of body mass index (BMI) and smoking are well established lifestyle risk factors for coronary heart disease (CHD) and stroke. If these two risk factors have a synergistic relationship, rigorous lifestyle modification may contribute to greater reduction in cardiovascular burden than previously expected. METHODS: A pooled analysis of individual participant data from 38 cohorts, involving 378,579 participants. Hazards ratios (HRs) and 95% confidence intervals (CIs) for BMI by cigarette smoking status were estimated using Cox proportional hazard models. RESULTS: During a mean follow-up of 3.8 years, 2706 CHD and 3264 strokes were recorded. There was a log-linear, positive relationship of BMI with CHD and stroke in both smokers and non-smokers with evidence of a synergistic effect of smoking on the association between BMI and CHD only: HRs (95% CIs) associated with a 2 kg/m2 higher BMI were 1.13 (1.10-1.17) in current smokers and 1.09 (1.06-1.11) in non-smokers (p-value for interaction=0.04). CONCLUSION: Smoking amplifies the positive association between BMI and CHD but not stroke. If confirmed, these results suggest that effective strategies that target smoking cessation and weight loss are likely to have a greater impact than anticipated on reducing the burden of CHD., published_or_final_version

The recent discovery1,2 of superconductivity in the three-dimensional perovskite system (Ba, K)BiO3 has added a new group of compounds to the family of high-transition-temperature (high-Tc) superconductors. (Ba, K)BiO3 contains a three-dimensional BiO network rather than the CuO planes found in two-dimensional high-Tc systems such as YBa2Cu3O7, (La1.85Sr0.15)CuO4, Bi–Ca–Sr–Cu–O and Tl–Ba–Ca–Cu–O. There are, however, a few key features shared by (Ba, K)BiO3 and the two-dimensional systems; for example the parent compounds BaBiO3 and La2CuO4 both have one valence electron per Bi (or Cu) and doping by K (or Sr) introduces holes into the system as charge carriers. To explore the possible effects of magnetism in the (Ba, K)BiO3 system and its related compounds, we have performed muon spin rotation (μSR) experiments on BaBiO3, (Ba, K)BiO3 and Ba(Bi0.9Pb0.1)O3, the latter being a member of another oxide superconductor system, Ba(Pb, Bi)O3 (ref. 3), to search for static magnetic order. In the present study, no signature of magnetic order was found in any of the above systems above T = 10 K. This is in sharp contrast to the two-dimensional systems, where static magnetic order appears in the vicinity of superconductivity.

Muon spin rotation and neutron scattering studies on powder and single-crystal specimens of La2CuO(4-y) are compared. The apparent difference between the muon and neutron results for the ordered moment in the antiferromagnetic state is interpreted as the signature of increasingly short-ranged spatial spin correlations with increasing oxygen content.

The internal magnetic fields in La 1.85 Sr 0.15 CuO 4 and YBa 2 Cu 3 O x have been investigated below 90 mK using muon spin rotation. In YBa 2 Cu 3 O x the magnetic order parameter remains constant with increasing x up until x =6.30 and then rapidly approaches zero just above x =6.44. We find little evidence for static or slowly fluctuating electronic moments in superconducting La 1.85 Sr 0.15 CuO 4 .

Zero- and longitudinal-field muon spin relaxation measurements on a polycrystal sample of a heavy fermion superconductor CeCu2.1 Si2 (T(c) = 0.7 K) have revealed an onset of static magnetic ordering below T approximately 0.8 K. The line shapes of the observed spectra in zero field indicate a wide distribution of static random local fields at muon sites, suggesting that the ordering is either spin glass or incommensurate spin-density-wave state. The observed width of the random local field at T = 0.05 K corresponds to a small averaged static moment of the order of 0.1 micro-B per formula unit.