Measurement of muon antineutrino quasielastic scattering on a hydrocarbon target at Eν ~ 3.5 GeV.

We have isolated ν(µ) charged-current quasielastic (QE) interactions occurring in the segmented scintillator tracking region of the MINERvA detector running in the NuMI neutrino beam at Fermilab. We measure the flux-averaged differential cross section, dσ/dQ², and compare to several theoretical models of QE scattering. Good agreement is obtained with a model where the nucleon axial mass, M(A), is set to 0.99 GeV/c² but the nucleon vector form factors are modified to account for the observed enhancement, relative to the free nucleon case, of the cross section for the exchange of transversely polarized photons in electron-nucleus scattering. Our data at higher Q² favor this interpretation over an alternative in which the axial mass is increased.

Measurement of muon neutrino quasielastic scattering on a hydrocarbon target at Eν ~ 3.5 GeV.

We report a study of ν(µ) charged-current quasielastic events in the segmented scintillator inner tracker of the MINERvA experiment running in the NuMI neutrino beam at Fermilab. The events were selected by requiring a µ- and low calorimetric recoil energy separated from the interaction vertex. We measure the flux-averaged differential cross section, dσ/dQ², and study the low energy particle content of the final state. Deviations are found between the measured dσ/dQ² and the expectations of a model of independent nucleons in a relativistic Fermi gas. We also observe an excess of energy near the vertex consistent with multiple protons in the final state.

Cerebral hemodynamics and cognitive performance in patients with asymptomatic carotid stenosis.

OBJECTIVE: The aim of this study was to investigate whether the presence of severe internal carotid artery stenosis may be associated with different cognitive performance in relation to the side of the stenosis and its hemodynamic consequences. METHODS: Eighty-three patients with asymptomatic severe unilateral internal carotid stenosis were included. A neuropsychological investigation including Verbal Fluency using phonemic and category access, Coloured Progressive Matrices, and Complex Figure Test Copy was performed. Each patient underwent an assessment of cerebrovascular reactivity (CVR) to hypercapnia with transcranial Doppler ultrasonography using the breath-holding index (BHI). Thirty healthy subjects comparable for demographic characteristics and vascular risk profile served as controls. Subjects with carotid stenosis were classified into two groups: preserved CVR (BHI > or =0.69), 48 patients (25 with left and 23 with right stenosis); and impaired CVR (BHI <0.69), 35 patients (19 with left and 16 with right stenosis). RESULTS: Subjects with left stenosis and reduced CVR had significantly lower performances at phonemic verbal fluency with respect to controls and the other groups of stenosis. In subjects with right stenosis and reduced CVR, scores obtained in Coloured Progressive Matrices and in Complex Figure Test Copy were significantly lower with respect to the other groups. CONCLUSIONS: These results suggest that an alteration of cerebrovascular reactivity may be responsible for reduction in some cognitive abilities involving the function of the hemisphere ipsilateral to carotid stenosis. Such findings may be of interest for providing a more comprehensive indication to surgical treatment in subgroups of subjects with asymptomatic carotid stenosis.

Equine growth hormone. Detection of immunoreactive sequences using poly- and monoclonal antibodies.

The immunochemical behavior of several fragments of equine growth hormone (eGH) was examined using competitive binding assays with antibodies (Abs) to eGH obtained from different sources. Antigenicity was detected within the sequences 5-72 and 73-123 by rabbit Abs to eGH and by three mouse monoclonal antibodies (MAbs) produced by using bovine growth hormone as immunogen, but showing heteroclitic properties towards eGH. The polyclonal Abs to eGH also recognized as immunoreactive two smaller peptides corresponding to the amino acid residues 52-72 and 110-123. By contrast, the heteroclitic Abs to eGH developed by hypopituitary patients therapeutically injected with human growth hormone failed to react with any eGH-derived fragment. The rabbit polyclonal Abs and the mouse MAbs scarely discriminated between native and S-carbamidomethylated eGH, while the heteroclitic human Abs detected a clear difference between the native and the modified hormone.

Human growth hormone. Immunochemical characterization of polypeptide fragments purified by reversed phase-high performance liquid chromatography.

Using HPLC it was possible to obtain fragments of human growth hormone, enzymatically or chemically cleaved, with a purity not previously attained. The immunoreactivity of these fragments was assayed with polyclonal or mouse monoclonal antibodies to the native hormone. Antigenicity was found in the peptide sequences derived from the two thirds of the molecule from the amino terminal end. No immunoreactivity was found in the sequence 135-191.