282 research outputs found
Spin-Spin Interaction In Matrix Theory
We calculate the spin dependent static force between two D0-branes in Matrix
theory. Supersymmetry relates velocity dependent potentials to spin dependent
potentials. The well known v^4/r^7 term is related to a theta^8/r^11 term,
where theta is the relative spin of the D0-branes. We calculate this term,
confirming that it is the lowest order contribution to the static potential,
and find its structure consistent with supergravity.Comment: 15 pages, LaTeX, uses feynmf.sty for diagrams. Reference added and
some labels on the diagrams restore
Mississippian Architecture: Temporal, Technological, and Spatial Patterning of Structures at the Toqua Site (40M R6)
The description and analysis of 130 Native American structures from the Toqua site (40MR6) provide an architectural typology for determining age, form, and function of Mississippian and historic Cherokee structural remains in East Tennessee. The Toqua structure, ranging in age from circa A.D. 1200 to circa A.D. 1780, are examined for temporal, technological, and spatial patterning and are compared with 469 structures from 58 Mississippian archaeological sites in the interior Southeastern United States.
Superimposed structures and radiocarbon determinations provided a temporal sequence of structure types. Closely controlled excavations, botanical analysis of construction materials, and technological studies of building materials provided insight into two successive construction techniques. An earlier flexed form of building construction had continuous elements making up both walls and roof. A later rigid form of building construction use separate components for walls, roof, and roof support system.
Study of structure size, form, proportion, elaboration, content, and location provided information concerning structure function and the relationship of contemporary structures to each other. Insight concerning the temporal, technological, and spatial patterning of Mississippian structures was obtained
Cardiovascular instrumentation for spaceflight
The observation mechanisms dealing with pressure, flow, morphology, temperature, etc. are discussed. The approach taken in the performance of this study was to (1) review ground and space-flight data on cardiovascular function, including earlier related ground-based and space-flight animal studies, Mercury, Gemini, Apollo, Skylab, and recent bed-rest studies, (2) review cardiovascular measurement parameters required to assess individual performance and physiological alternations during space flight, (3) perform an instrumentation survey including a literature search as well as personal contact with the applicable investigators, (4) assess instrumentation applicability with respect to the established criteria, and (5) recommend future research and development activity. It is concluded that, for the most part, the required instrumentation technology is available but that mission-peculiar criteria will require modifications to adapt the applicable instrumentation to a space-flight configuration
Conceptual design study for a teleoperator visual system, phase 2
An analysis of the concept for the hybrid stereo-monoscopic television visual system is reported. The visual concept is described along with the following subsystems: illumination, deployment/articulation, telecommunications, visual displays, and the controls and display station
In-flight maintenance study Final report
Sample system analysis, MF requirements, redesign, and packaging desig
Large entropy production inside black holes: a simple model
Particles dropped into a rotating black hole can collide near the inner
horizon with enormous energies. The entropy produced by these collisions can be
several times larger than the increase in the horizon entropy due to the
addition of the particles. In this paper entropy is produced by releasing large
numbers of neutrons near the outer horizon of a rotating black hole such that
they collide near the inner horizon at energies similar to those achieved at
the Relativistic Heavy Ion Collider. The increase in horizon entropy is
approximately 80 per dropped neutron pair, while the entropy produced in the
collisions is 160 per neutron pair. The collision entropy is produced inside
the horizon, so this excess entropy production does not violate Bousso's bound
limiting the entropy that can go through the black hole's horizon. The
generalized laws of black hole thermodynamics are obeyed. No individual
observer inside the black hole sees a violation of the second law of
thermodynamicsComment: 10 page
Application of advanced technology to space automation
Automated operations in space provide the key to optimized mission design and data acquisition at minimum cost for the future. The results of this study strongly accentuate this statement and should provide further incentive for immediate development of specific automtion technology as defined herein. Essential automation technology requirements were identified for future programs. The study was undertaken to address the future role of automation in the space program, the potential benefits to be derived, and the technology efforts that should be directed toward obtaining these benefits
Students Take Lead to Educate Faculty on the Use of Sex and Gender Terminology in Pre-clinical Courses
TOP WINNER
Student leaders in the Lesbian, Gay, Bisexual and Transgender People in Medicine student run organization at the Medical College of Wisconsin noticed that curricular language around sex and gender was absent and/or incorrect in the pre-clinical medical school (M1/M2) courses. After reaching out to the M2 Endocrine/Repro Unit course director, students prepared a report to present to all M1/M2 Course Directors.
Objectives: One goal of the report was to “educate the educators” so that faculty would have better understanding of the distinction between sex and gender. Ultimately this would translate to the students and improve overall future patient care.
Methods: A presentation was developed and given at the quarterly M1/M2 course director meeting (Fall 2019). Information included statistics from the 2015 US Transgender Survey which underscored that ignorance surrounding sex versus gender terminology could result in an environment in which patients do not seek care. The student presentation comprehensively explained the definitions of sex, gender, cisgender and transgender. Course directors were given action items to evaluate their courses and afirm that terms were used appropriately. Student leaders provided contact information for faculty feedback.
Conclusions/Impact: In February 2020, students reported of changes in some courses. For example, the M2 cardiovascular unit led off the session on women and heart disease with sex and gender definitions provided by students. Cardiovascular risks of hormonal therapy for transgender patients was included. Students noted that language around sex and gender in the M2 endocrine-repro unit was consistently correct (female not woman when discussing XX fetus). A M1 pharmacology lecture included the student\u27s definition slide as prelude to discussion of male/female differences in drug response. With little effort, students played an integral role in improving curricular content related to sex and gender medicine and further supporting the model that students are important drivers of change.https://jdc.jefferson.edu/sexandgenderhealth/1019/thumbnail.jp
D-brane Black Holes: Large-N Limit and the Effective String Description
We address the derivation of the effective conformal field theory description
of the 5-dimensional black hole, modelled by a collection of D1- and D5-
branes, from the corresponding low energy U(Q_1)xU(Q_5) gauge theory. Finite
horizon size at weak coupling requires both Q_1 and Q_5 to be large. We derive
the result in the moduli space approximation (say for Q_1>Q_5) and appeal to
supersymmetry to argue its validity beyond weak coupling. As a result of a
combination of quenched Z_{Q_1} Wilson lines and a residual Weyl symmetry, the
low-lying excitations of the U(Q_1)xU(Q_5) gauge theory are described by an
effective N=4 superconformal field theory with c=6 in 1+1 dimensions, where the
space is a circle of radius RQ_1Q_5. We also discuss the appearance of a
marginal perturbation of the effective conformal field theory for large but
finite values of Q_5.Comment: 15 pages, LaTeX, some comments added to make the arguments in
sections 4 and 5 more precise, to appear in Phys. Lett.
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