2,066 research outputs found
A new description of motion of the Fermionic SO(2N+2) top in the classical limit under the quasi-anticommutation relation approximation
The boson images of fermion SO(2N+1) Lie operators have been given together
with those of SO(2N+2) ones. The SO(2N+1) Lie operators are generators of
rotation in the (2N+1)-dimensional Euclidian space (N: number of
single-particle states of the fermions). The images of fermion
annihilation-creation operators must satisfy the canonical anti-commutation
relations, when they operate on a spinor subspace. In the regular
representation space we use a boson Hamiltonian with Lagrange multipliers to
select out the spinor subspace. Based on these facts, a new description of a
fermionic SO(2N+2) top is proposed. From the Heisenberg equations of motions
for the boson operators, we get the SO(2N+1) self-consistent field (SCF)
Hartree-Bogoliubov (HB) equation for the classical stationary motion of the
fermion top. Decomposing an SO(2N+1) matrix into matrices describing paired and
unpaired modes of fermions, we obtain a new form of the SO(2N+1) SCF equation
with respect to the paired-mode amplitudes. To demonstrate the effectiveness of
the new description based on the bosonization theory, the extended HB
eigenvalue equation is applied to a superconducting toy-model which consists of
a particle-hole plus BCS type interaction. It is solved to reach an interesting
and exciting solution which is not found in the traditional HB eigenvalue
equation, due to the unpaired-mode effects. To complete the new description,
the Lagrange multipliers must be determined in the classical limit. For this
aim a quasi anti-commutation-relation approximation is proposed. Only if a
certain relation between an SO(2N+1) parameter z and the N is satisfied,
unknown parameters k and l in the Lagrange multipliers can be determined
withuout any inconcistency.Comment: 36 pages, no figures, typos corrected, published versio
Socially Isolated Cambodians in the US: Recommendations for Health Promotion
Cambodian genocide survivors experience health disparities associated with their traumatic experiences. Cambodian community organizations in the United States are severely challenged to serve these survivors. Community leaders have identified a sub-set of community members of particular concern: those at either end of the age spectrum (elders and young people) who are socially isolated. As part of a larger community-based participatory research project, we conducted a focus group with seven Cambodian community leaders from six cities that sought to better understand the phenomenon of social isolation of Cambodian elders and young people in order to inform health promotion efforts. Cambodian leaders expressed keen concern for those community members who rarely seem to leave their homes or interact with the Cambodian community. Prominent themes identified by leaders related to isolation were: a generational pattern; benefits of extended family; health concerns; the impact of stigma and fear; lack of sufficient resources; and cultural influences. In addition, leaders identified several possible solutions to address the phenomenon of social isolation in their communities. Health promotion efforts in this population should identify isolated individuals and enhance their social connectedness and support networks as part of a larger integrated effort
Anomaly-Free Supersymmetric SO(2N+2)/U(N+1) sigma-Model Based on the SO(2N+1) Lie Algebra of the Fermion Operators
The extended supersymmetric (SUSY) sigma-model has been proposed on the bases
of SO(2N+1) Lie algebra spanned by fermion annihilation-creation operators and
pair operators. The canonical transformation, extension of an SO(2N) Bogoliubov
transformation to an SO(2N+1) group, is introduced. Embedding the SO(2N+1)
group into an SO(2N+2) group and using SO(2N+2)/U(N+1) coset variables, we have
investigated the SUSY sigma-model on the Kaehler manifold, the coset space
SO(2N+2)/U(N+1). We have constructed the Killing potential, extension of the
potential in the SO(2N)/U(N) coset space to that in the SO(2N+2)/U(N+1) coset
space. It is equivalent to the generalized density matrix whose diagonal-block
part is related to a reduced scalar potential with a Fayet-Ilipoulos term. The
f-deformed reduced scalar potential is optimized with respect to vacuum
expectation value of the sigma-model fields and a solution for one of the
SO(2N+1) group parameters has been obtained. The solution, however, is only a
small part of all solutions obtained from anomaly-free SUSY coset models. To
construct the coset models consistently, we must embed a coset coordinate in an
anomaly-free spinor representation (rep) of SO(2N+2) group and give
corresponding Kaehler and Killing potentials for an anomaly-free
SO(2N+2)/U(N+1) model based on each positive chiral spinor rep. Using such
mathematical manipulation we construct successfully the anomaly-free
SO(2N+2)/U(N+1) SUSY sigma-model and investigate new aspects which have never
been seen in the SUSY sigma-model on the Kaehler coset space SO(2N)/U(N). We
reach a f-deformed reduced scalar potential. It is minimized with respect to
the vacuum expectation value of anomaly-free SUSY sigma-model fields. Thus we
find an interesting f-deformed solution very different from the previous
solution for an anomaly-free SO(2.5+2)/(SU(5+1)*U(1)) SUSY sigma-model.Comment: 24 pages, no fiure
Socially Isolated Cambodians in the US
Community organizations in the United States are severely challenged to serve Cambodian refugees who experience health disparities associated with their traumatic experiences. Community leaders have identified a sub-set of community members of particular concern: those at either end of the age spectrum (elders and young people) who are socially isolated. As part of a larger community-based participatory research project, we conducted a focus group with seven Cambodian community leaders from six cities. The study sought to better understand the phenomenon of social isolation of Cambodian elders and young people in order to inform health promotion efforts. Cambodian leaders expressed keen concern for those community members who rarely seem to leave their homes or interact with the Cambodian community. Prominent themes identified by leaders related to isolation were: a generational pattern; benefits of extended family; health concerns; cultural influences and language; impact of stigma; fear and safety concerns; and lack of sufficient resources. In addition, leaders identified several possible solutions to address the phenomenon of social isolation in their communities. Health promotion efforts with this population should identify isolated individuals and enhance their social connectedness and support networks as part of a larger integrated effort
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