Lymphocyte reactivity in patients with carcinoma of the breast and large bowel.

The reactivity of lymphocytes from patients with either carcinoma of the breast or large bowel has been studied using the human to mouse normal lymphocyte transfer (NLT) reaction. It was found that, in the case of breast cancer, there was a direct correlation between the clinical stage and a reduced NLT reaction. Only patients with regional lymph node or generalized metastases showed significantly reduced lymphocyte reactivity. However, in the case of large bowel cancer there was a generalized reduction in NLT reactivity which was independent of the clinical stage. Incubation of lymphocytes from individuals without neoplastic disease in serum or plasma from breast cancer patients, showing reduced NLT reactivity, resulted in a reduced NLT reaction. This appears to be indicative of the presence of circulating "blocking factor" in such patients

Do Multi-Paddock Systems Increase Evenness of Grazing at the Paddock Scale?

There is ongoing debate about the benefits of multi-paddock rotationally grazed systems compared to continuous grazing (Briske et al. 2008). One of the purported benefits of high density short duration grazing is more spatially uniform defoliation. A commercial-scale trial in northern Australia (Hunt et al. 2013) compared continuously grazed paddocks to cell grazed and wet season spelled systems in newly developed paddocks. This paper reports the effect of grazing system on defoliation with distance to water through time

Bright X-ray radiation from plasma bubbles in an evolving laser wakefield accelerator

We show that the properties of the electron beam and bright x-rays produced by a laser wakefield accelerator can be predicted if the distance over which the laser self-focuses and compresses prior to self-injection is taken into account. A model based on oscillations of the beam inside a plasma bubble shows that performance is optimised when the plasma length is matched to the laser depletion length. With a 200~TW laser pulse this results in an x-ray beam with median photon energy of \unit[20]{keV}, $> 6\times 10^{8}$ photons above \unit[1]{keV} per shot and a peak brightness of \unit[3 \times 10^{22}]{photons~s^{-1}mrad^{-2}mm^{-2} (0.1\% BW)^{-1}}.Comment: 5 pages, 4 figure

Ultra-high brilliance multi-MeV γ\gamma-ray beam from non-linear Thomson scattering

We report on the generation of a narrow divergence ($\theta\approx 2.5$ mrad), multi-MeV ($E_\text{MAX} = 18$ MeV) and ultra-high brilliance ($\approx 2\times10^{19}$ photons s$^{-1}$ mm$^{-2}$ mrad $^{-2}$ 0.1\% BW) $\gamma$-ray beam from the scattering of an ultra-relativistic laser-wakefield accelerated electron beam in the field of a relativistically intense laser (dimensionless amplitude $a_0\approx2$). The spectrum of the generated $\gamma$-ray beam is measured, with MeV resolution, seamlessly from 6 MeV to 18 MeV, giving clear evidence of the onset of non-linear Thomson scattering. The photon source has the highest brilliance in the multi-MeV regime ever reported in the literature

Inverse problem for wave equation with sources and observations on disjoint sets

We consider an inverse problem for a hyperbolic partial differential equation on a compact Riemannian manifold. Assuming that $\Gamma_1$ and $\Gamma_2$ are two disjoint open subsets of the boundary of the manifold we define the restricted Dirichlet-to-Neumann operator $\Lambda_{\Gamma_1,\Gamma_2}$. This operator corresponds the boundary measurements when we have smooth sources supported on $\Gamma_1$ and the fields produced by these sources are observed on $\Gamma_2$. We show that when $\Gamma_1$ and $\Gamma_2$ are disjoint but their closures intersect at least at one point, then the restricted Dirichlet-to-Neumann operator $\Lambda_{\Gamma_1,\Gamma_2}$ determines the Riemannian manifold and the metric on it up to an isometry. In the Euclidian space, the result yields that an anisotropic wave speed inside a compact body is determined, up to a natural coordinate transformations, by measurements on the boundary of the body even when wave sources are kept away from receivers. Moreover, we show that if we have three arbitrary non-empty open subsets $\Gamma_1,\Gamma_2$, and $\Gamma_3$ of the boundary, then the restricted Dirichlet-to-Neumann operators $\Lambda_{\Gamma_j,\Gamma_k}$ for $1\leq j<k\leq 3$ determine the Riemannian manifold to an isometry. Similar result is proven also for the finite-time boundary measurements when the hyperbolic equation satisfies an exact controllability condition

Polarization Dependence of Bulk Ion Acceleration from Ultrathin Foils Irradiated by High-Intensity Ultrashort Laser Pulses

The acceleration of ions from ultrathin (10-100 nm) carbon foils has been investigated using intense (∼ 6 x1020 Wcm-2), ultrashort (45 fs) laser pulses, highlighting a strong dependence of the ion beam parameters on the laser polarization, with circularly polarized (CP) pulses producing the highest energies for both protons and carbons (25-30 MeV/nucleon); carbon ion energies obtained employing CP pulses were signicantly higher (∼2.5 times) than for irradiations employing linearly polarized (LP) pulses. Particle-in-cell simulations indicate that Radiation Pressure Acceleration becomes the dominant mechanism for the thinnest targets and CP pulses

Soft X-ray harmonic comb from relativistic electron spikes

We demonstrate a new high-order harmonic generation mechanism reaching the `water window' spectral region in experiments with multi-terawatt femtosecond lasers irradiating gas jets. A few hundred harmonic orders are resolved, giving uJ/sr pulses. Harmonics are collectively emitted by an oscillating electron spike formed at the joint of the boundaries of a cavity and bow wave created by a relativistically self-focusing laser in underdense plasma. The spike sharpness and stability are explained by catastrophe theory. The mechanism is corroborated by particle-in-cell simulations

Ursinus College Alumni Journal, July 1955

Commencement address 1955 • The college honors Dr. I. S. Leinbach • Ground broken for the new women\u27s dormitories • News from the registrar\u27s office • Armstrong preaches baccalaureate sermon • Summer program offered again at Ursinus • Meistersingers make spring tour • The magic hour May Day theme • New student union in Bomberger basement • Alpha Phi Omega campus project • Alumni celebrate graduation anniversary • Class of \u2755 elects permanent class officers • Keyser \u2710 and Krug \u2737 honored by educators • Alumni elect new officers for 1955-57 • York County alumni sponsor Noss film • J. A. Hunsicker \u2792 recipient of award • Regional alumni groups hold annual meetings • French Department faculty member active in research • Barbara Yerkes \u2749 teacher and friend of Bristol High students • Sports review • 1955 baseball season • 1955 tennis season • Varsity Club honors outstanding athletes • 1955 women\u27s sports • 1955 track season • Ursinus participates in Ford foundation program for teachers • Alumni participate in Red Lion jubilee • News about ourselves • Weddings • Birthshttps://digitalcommons.ursinus.edu/alumnijournal/1052/thumbnail.jp