5 research outputs found
Analytic Representation of The Dirac Equation
In this paper we construct an analytical separation (diagonalization) of the
full (minimal coupling) Dirac equation into particle and antiparticle
components. The diagonalization is analytic in that it is achieved without
transforming the wave functions, as is done by the Foldy-Wouthuysen method, and
reveals the nonlocal time behavior of the particle-antiparticle relationship.
We interpret the zitterbewegung and the result that a velocity measurement (of
a Dirac particle) at any instant in time is, as reflections of the fact that
the Dirac equation makes a spatially extended particle appear as a point in the
present by forcing it to oscillate between the past and future at speed c. From
this we infer that, although the form of the Dirac equation serves to make
space and time appear on an equal footing mathematically, it is clear that they
are still not on an equal footing from a physical point of view. On the other
hand, the Foldy-Wouthuysen transformation, which connects the Dirac and square
root operator, is unitary. Reflection on these results suggests that a more
refined notion (than that of unitary equivalence) may be required for physical
systems
Activation of T lymphocytes for the adoptive immunotherapy of cancer
Background: Adoptive immunotherapy of malignancy involves the passive transfer of antitumor-reactive cells into a host in order to mediate tumor regression. Based on animal models, the transfer of immune lymphoid cells can eradicate widely disseminated tumors and establish long-term systemic immunity. Critical for successful adoptive immunotherapy is the ability to isolate large numbers of immune cells. For clinical therapy, it will require the development of in vitro methods to promote the sensitization and propagation of tumor-reactive cells. However, this is formidable task since human cancers are postulated to be poorly immunogenic because of their spontaneous origins.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41399/1/10434_2006_Article_BF02303568.pd