Projectile Δ\Delta Excitations in p(p,n)Nπp(p,n)N\pi Reactions

It has recently been proven from measurements of the spin-transfer coefficients $D_{xx}$ and $D_{zz}$ that there is a small but non-vanishing $\Delta S=0$ component $\sigma_{0}$, in the inclusive $p(p,n)N\pi\,$ reaction cross section $\sigma\,$. It is shown that the dominant part of the measured $\sigma_{0}$ can be explained in terms of the projectile $\Delta$ excitation mechanism. An estimate is further made of contributions to $\sigma_{0}$ from s-wave rescattering process. It is found that s-wave rescattering contribution is much smaller than the contribution coming from projectile $\Delta$ excitation mechanism. The addition of s-wave rescattering contribution to the dominant part, however, improves the fit to the data.Comment: 9 pages, Revtex, figures can be obtained upon reques

Searches for New Quarks and Leptons Produced in Z-Boson Decay

We have searched for events with new-particle topologies in 390 hadronic Z decays with the Mark II detector at the SLAC Linear Collider. We place 95%-confidence-level lower limits of 40.7 GeV/c^2 for the top-quark mass, 42.0 GeV/c^2 for the mass of a fourth-generation charge - 1/3 quark, and 41.3 GeV/c^2 for the mass of an unstable Dirac neutral lepton

Intracranial hypotension following traumatic brain injury: a diagnostic and therapeutic challenge.

BACKGROUND: Intracranial hypotension (IH) is a recognised cause of coma, however, the diagnosis is often challenging, especially in patients with superimposed traumatic brain injury (TBI). CASE REPORT: We report a case of a 67-year-old patient who became comatose following evacuation of bilateral acute subdural haematomas with concurrent respiratory failure. Imaging and intraparenchymal intracranial pressure (ICP) monitoring confirmed secondary IH. She was managed with an epidural blood patch, and a 72 hours period in the trendelenberg position guided by ICP monitoring and clinical assessment. She subsequently made an excellent neurological recovery from an initial Glasgow coma scale (GCS) of 3 to a GCS of 15. CONCLUSION: A diagnosis of secondary IH can easily be missed in patients who have suffered a primary brain injury. In patients with a poor neurological recovery, clinicians should rule out secondary IH as a potential cause as immediate treatment can lead to a profound clinical improvement