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An overview of the STAR experiment at the Relativistic Heavy Ion Collider is presented. The experiment will concentrate on the measurement of particle production and jet production at midrapidity in a search for the Quark-Gluon Plasma. These hadronic observables will be studied on an event-by-event basis to determine the thermodynamics of single events and to identify special and unusual events. The physics addressed by STAR is discussed.

Multiplicity distributions in high-energy hadronic reactions are broader in the central rapidity region than in the fragmentation region. An explanation of this phenomenon in terms of a stochastic branching equation is given supporting the picture of two sources, one mainly chaotic and one essentially coherent.

Annihilation of ``heavy'' antinuclei, such as d\ifmmode\bar\else\textasciimacron\fi{}, t\ifmmode\bar\else\textasciimacron\fi{}, or \ensuremath{\alpha}\ifmmode\bar\else\textasciimacron\fi{} in nuclear matter could serve to probe whether the constituent antinucleons annihilate independently of each other or whether a single fireball is formed. In the latter case the total meson multiplicity distribution should have a lower mean and a larger relative width than in the trivial case. The meson spectrum would be correspondingly harder.

Because prosthetic grafting to the venous system has a low patency rate, endothelial cell seeding has been used to enhance this rate. The effects of heterologous (porcine) or homolo gous (canine omental) endothelial seeding and of graft material (dacron or polytetrafluoroethylene—PTFE) on the patency rate of venous grafts were evaluated in this study. Fifty-three grafts (10 cm x 8 mm ID) were inserted in dogs' vena cava. All animals were treated with aspi rin. Patency rate was evaluated at day 4 (cavography) or at day 32 (his tology). The authors found that: (1) da cron grafts provided a poor venous conduit for seeding purposes; (2) PTFE grafts, whether seeded with omental canine or porcine endothelial cells, had a consistently high patency rate; and (3) although further studies would be needed, heterologous and homologous cell seeding might repre sent acceptable alternatives to autolo gous seeding.

The purpose of this study was to evaluate the effectiveness of aspirin (ASA) and porcine endothelial cell seeding in improving the patency rate of vena cava grafts. Thirty-nine dogs underwent infrarenal vena cava replacement by 10 cm lengths of 8 mm I.D. ringed polytetrafluoroethylene grafts. Thirty-one grafts were seeded with 1-1.5 x 10(6) porcine aortic endothelial cells while eight were not (GIII). Of the seeded group, 16 animals received no ASA (GI), while 15 others (GII) were given ASA (325 mg) daily starting two days preoperatively and continuing until sacrifice. Venograms were performed on the fourth postoperative day. Grafts were harvested 32 days after insertion and evaluated for patency rate and endothelialized surfaces. The 32-day patency rate was significantly higher for GII than for GI and III animals (67% vs. 13 and 25% respectively). Endothelialized surface was higher in GII than Gi and III (67% vs. 16% and 18% respectively). We conclude that endothelial cell seeding alone does not prevent graft closure and that a combination of ASA and cell seeding significantly increases the patency rate of vena cava grafts.

Quantum statistics including a finite coherence length is applied to the study of multiplicity distributions from high-energy hadronic collisions measured in finite rapidity windows. A new scaling property in rapidity (``\ensuremath{\beta} scaling'') is derived. It contains forward-backward correlations as a special case. Agreement with data is satisfactory. We find strong indications for an increase of chaoticity with energy. Further experimental tests are suggested.

Projectile fragments formed in the interaction of $0.9A$- and $1.8A$-GeV $^{40}\mathrm{Ar}$ ions with a Cu disk interact with a second Cu disk and the relative yields of products in the two disks are measured by radioactivation techniques as a function of the distance between them. The data at $1.8A$ GeV demand either (1) decay in flight (${t}_{\frac{1}{2}}\ensuremath{\approx}{10}^{\ensuremath{-}10}$ s) of some projectile fragments having large cross sections or (2) production of secondaries with unexpectedly large transverse momenta.

The health risks from low-dose sparsely ionizing (low-LET) radiation have been the subject of continued debate. At present, quantitative estimates of risk are extremely uncertain due to the controversy surrounding both the dosimetry for A-bomb survivor data and the choice of mathematical models for extrapolating risk from high to low doses. Nevertheless, much can be learned about the nature of the health risks by reviewing the epidemiologic literature. We present a summary of diseases which have been associated with low-LET radiation (less than 1000 rad) in at least two independent studies, according to the mean cumulative organ dose at which the disease was observed. At organ doses of less than or equal to 50 rad, the only diseases that have been reported consistently are thyroid cancer, salivary gland tumors, and leukemia. The first two diseases were observed in association with x-ray epilation of the scalp for tinea capitis, a therapy which is no longer employed. On the other hand, leukemia has been observed repeatedly to occur at cumulative doses of greater than or equal to 30 rad low-LET radiation.

We evaluated the possible relation between use of non-nutritive sweeteners and bladder cancer using data obtained from the National Cancer Institute Bladder Cancer Study under the Freedom of Information Act. In the general study group, there was no evidence for an association between non-nutritive sweeteners and bladder cancer. Control for a variety of factors through multivariate techniques diminished the plausibility of earlier interpretations of these data, which had raised the possibility that certain subgroups of users or non-nutritive sweeteners might be at an increased risk for bladder cancer. We found that the putative effects of non-nutritive sweeteners were not consistent among subgroups with similar baseline risk, did not display consistent dose-response trends, and were subject to considerable sampling error. We concluded that the data provided little evidence that non-nutritive sweeteners increase risk for bladder cancer among subgroups of users, and that definitive evidence on this question is beyond the reach of conventional research.

It is shown that bo.D-l:xxly decays of unstable particles produced in very high-energy hadronic collisions nmst show up as peaks in the single-particle mc:.m:mtum spectra of their decay products obseIVed near YCMS ~ O. objects whenever these peaks distort the steeply falling PT-continuum.

The paper gives an analysis of the 1157 faults due to lightning which have occurred during 14 years on the 5 900 miles of line of the British Grid system.It is shown that the fault rate varies approximately inversely with the system voltage, typical figures being 1 fault per 100 miles per year for the 132-kV lines, and 3.8 for the 33-kV lines. The annual, seasonal and diurnal variations in the incidence of lightning faults are studied, and figures are given for the mean fault rates in the different Grid areas. Factors of importance in the design of overhead systems are discussed, such as the reliability of double-circuit lines, the proportion of single-phase to multi-phase flashovers, and the effect of tower footing resistance. It is found that overhead lines can be put back into service again immediately after a lightning faultin 9 cases out of 10.It is estimated that, for an average Grid substation, there is not more than one fault due to a direct stroke in about 70 years. The ecords of transformer breakdowns are discussed in some detail, and it is shown that the most serious form of breakdown, failure of windings, has involved, on theaverage, 0.3 transformer per 100 transformers per year.The protective devices used on the Grid system are described, and information is included on the performance in service of rod gaps, expulsion tubes and Petersen coils. The rod gaps and expulsion tubes appear to have provided a useful measure of protection, and the 33-kV system fault data lead to the conclusion that the Petersen coils suppress about 50% of the faults. Some information, based on operating experience, is given on the protective effect of terminal cables.Finally, the use of radio methods for giving thunderstorm warnings and statistical information on lightning severity is briefly discussed.

REGARDLESS of the methods preferred in the treatment of venous thrombosis, the physiologic events in the process of thrombus formation must guide the physician in his therapeutic considerations. What is called a vascular thrombus today was considered an outgrowth of the vascular wall by anatomists until the middle of the past century. Rudolf Virchow1was the first one to recognize these "outgrowths" as blood clots. He also described the mechanism of embolism, and his concept of thromboembolic disease is fundamentally as dominant now as it was one hundred years ago. Among the many papers which have appeared since Virchow's classic work, a few can be listed as contributing substantially to a better understanding of thromboembolic disease. Glénard2and von Baumgarten3showed independently that blood does not clot, even if kept stagnant for days between ligatures applied to a vein, as long as the vascular lining remains