Observation of Wakefields and Resonances in Coherent Synchrotron Radiation.

We report on high resolution measurements of resonances in the spectrum of coherent synchrotron radiation (CSR) at the Canadian Light Source (CLS). The resonances permeate the spectrum at wave number intervals of 0.074  cm(-1), and are highly stable under changes in the machine setup (energy, bucket filling pattern, CSR in bursting or continuous mode).

Elastic compton scattering from the deuteron and nucleon polarizabilities.

Cross sections for elastic Compton scattering from the deuteron were measured over the laboratory angles straight theta(gamma) = 35 degrees -150 degrees. Tagged photons in the laboratory energy range E(gamma) = 84-105 MeV were scattered from liquid deuterium and detected in the large-volume Boston University NaI spectrometer. Using the calculations of Levchuk and L'vov, along with the measured differential cross sections, the isospin-averaged nucleon polarizabilities in the deuteron were estimated.

Laboratory diagnosis of inherited protein S deficiency.

The authors investigated assays for free protein S (ProS) antigen, total ProS antigen, and ProS crossed immunoelectrophoresis (CIEP) in the diagnosis of type 1 inherited ProS deficiency. Accurate measurement of the hemostatically important free ProS required showing that, on each specimen, precipitation of the C4b-binding protein (C4b-BP)/protein S complex (C4b-BP/ProS) by polyethylene glycol-8,000 (PEG) was complete. The authors showed this by doing a ProS CIEP on the same PEG supernate that was used for quantitative measurement of free ProS.

Heparin cofactor II assay. Elimination of heparin and antithrombin-III effects.

Functional assays for heparin cofactor II (HC-II) are based on the inactivation of thrombin by HC-II in the presence of dermatan sulfate (DS). Residual thrombin is measured in a chromogenic assay. Interference by the antithrombin-III (AT-III)/heparin complex, which also rapidly inactivates thrombin, must be eliminated from the HC-II test system.

Kallikrein inhibition and C1-esterase inhibitor levels in patients with the lupus inhibitor.

It has been suggested that kallikrein inhibition may predispose patients with the lupus inhibitor to thrombosis by interfering with the Factor XII-mediated activation of plasminogen. To further investigate this suggestion, the authors measured kallikrein inhibition in 19 patients with the lupus inhibitor. They found that kallikrein inhibition was greater than 100% of that of a normal plasma pool in all patients and greater than 125% in 11 of 19.

Abnormal prothrombin crossed-immunoelectrophoresis in patients with lupus inhibitors.

Prothrombin deficiency has been known to occur in association with lupus inhibitors for over 25 years. We studied 21 patients with lupus inhibitors and found that four of five with prothrombin deficiency and ten of 16 with quantitatively normal prothrombin had abnormal prothrombin crossed-immunoelectrophoresis (CIEP) characterized by material moving slower in the first dimension of electrophoresis than normal prothrombin. In two patients with prothrombin deficiency, all prothrombin measured by quantitative assay and all slow-moving material on CIEP were removed by treatment with Staphylococcal protein A (SPA).