Role of relativity and nucleon compositeness in few-body systems

Recent progress is reviewed in four areas where new experimental data have been obtained: proton-proton bremsstrahlung, threshold pion production in proton-proton collisions, elastic electron-deuteron scattering and deuteron photodisintegration at several GeV photon energy. Relativistic effects are expected to be significant in these processes. High energy photodisintegration suggests that partonic behavior could be relevant in subamplitudes at large momentum transfer.Comment: Invited talk at XVII European Conference on Few-Body Problems in Physics, Sept. 11-16, 2000, Evora, Portugal. (12 pages, 2 postscript figures

Directionally solidified superalloy

Cobalt-tungsten superalloy has improved stress rupture characteristics. Appropriate additions were made to this base alloy using microprobe analyses and a fractional factorial experiment

Analysis of reinforcement learning strategies for predation in a mimic-model prey environment

In this paper we propose a mathematical learning model for a stochastic automaton simulating the behaviour of a predator operating in a random environment occupied by two types of prey: palatable mimics and unpalatable models. Specifically, a well known linear reinforcement learning algorithm is used to update the probabilities of the two actions, eat prey or ignore prey, at every random encounter. Each action elicits a probabilistic response from the environment that can be either favorable or unfavourable. We analyse both fixed and varying stochastic responses for the system. The basic approach of mimicry is defined and a short review of relevant previous approaches in the literature is given. Finally, the conditions for continuous predator performance improvement are explicitly formulated and precise definitions of predatory efficiency and mimicry efficiency are also provided

Hypersonic turbulent boundary layer studies at cold wall conditions

Skin friction and heat transfer rate in hypersonic turbulent boundary layer flow over flat plates and cold nozzle wall

Rare External Jugular Vein Pseudoaneurysm

External jugular vein pseudoaneurysm is a very rare cause of a neck mass due to the low pressure venous system. This case demonstrates a 27-year-old female who presented to the emergency department with a non-tender, compressible, left-sided neck mass that enlarged with valsalva and talking, and intermittent paresthesias. Upon workup, she was diagnosed with an external jugular vein pseudoaneurysm. Complications of this diagnosis are mentioned in the literature; however, most patients with an external jugular vein pseudoaneurysm or aneurysm can be safely discharged with close follow-up with a vascular surgeon

Membrane consisting of polyquaternary amine ion exchange polymer network interpenetrating the chains of thermoplastic matrix polymer

An ion exchange membrane was formed from a solution containing dissolved matrix polymer and a set of monomers which are capable of reacting to form a polyquaternary ion exchange material; for example vinyl pyride and a dihalo hydrocarbon. After casting solution and evaporation of the volatile component's, a relatively strong ion exchange membrane was obtained which is capable of removing anions, such as nitrate or chromate from water. The ion exchange polymer forms an interpenetrating network with the chains of the matrix polymer