7,085 research outputs found
A controlled study of hostile-helpless states of mind among borderline and dysthymic women
The aim of this study was to determine whether women with borderline personality disorder (BPD) are more likely than those with dysthymia to manifest contradictory Hostile-Helpless (HH) states of mind. A reliable rater blind to diagnosis evaluated features of such mental representations in transcripts of Adult Attachment Interviews from 12 women with BPD and 11 women with dysthymia of similar socioeconomic status (SES), all awaiting psychotherapy. In keeping with three hierarchical (non-independent) a priori predictions regarding the mental representations of women with BPD, the results were that (a) all those with BPD, compared with half the group with dysthymia, displayed HH states of mind; (b) those with BPD manifested a significantly higher frequency of globally devaluing representations; and (c) they exhibited a strong trend toward identifying with the devalued hostile caregiver (58% BPD vs. 18% dysthymic). In addition, significantly more BPD than dysthymic patients made reference to controlling behavior towards attachment figures in childhood. These findings offer fresh insights into the nature of BPD and extend previous evidence concerning affected individuals' patterns of thinking and feeling about childhood attachment figures
Mapping the invisible hand: a body model of a phantom limb
After amputation, individuals often have vivid experiences of their absent limb (i.e., a phantom limb). Therefore, oneās conscious image of oneās body cannot depend on peripheral input only (Ramachandran & Hirstein, 1998). However, the origin of phantom sensations is hotly debated. Reports of vivid phantoms in the case of congenital absence of the limb show that memory of former body state is not necessary (Brugger et al., 2000). According to one view, phantoms may reflect innate organization of sensorimotor cortices (Melzack, 1990). Alternatively, phantoms could reflect generalization from viewing other peopleās bodies (Brugger et al., 2000), a sensorimotor example of the classic theory that understanding oneself follows from understanding the āgeneralized otherā (Mead, 1934, p. 154). Because phantom limbs cannot be stimulated, sensory testing cannot directly compare visual and somatosensory influences on representations of phantom limbs. Consequently, empirical investigation of phantoms is limited
Capture and Decay of Electroweak WIMPonium
The spectrum of Weakly-Interacting-Massive-Particle (WIMP) dark matter
generically possesses bound states when the WIMP mass becomes sufficiently
large relative to the mass of the electroweak gauge bosons. The presence of
these bound states enhances the annihilation rate via resonances in the
Sommerfeld enhancement, but they can also be produced directly with the
emission of a low-energy photon. In this work we compute the rate for SU(2)
triplet dark matter (the wino) to bind into WIMPonium -- which is possible via
single-photon emission for wino masses above 5 TeV for relative velocity v <
O(10^{-2}) -- and study the subsequent decays of these bound states. We present
results with applications beyond the wino case, e.g. for dark matter inhabiting
a nonabelian dark sector; these include analytic capture and transition rates
for general dark sectors in the limit of vanishing force carrier mass,
efficient numerical routines for calculating positive and negative-energy
eigenstates of a Hamiltonian containing interactions with both massive and
massless force carriers, and a study of the scaling of bound state formation in
the short-range Hulthen potential. In the specific case of the wino, we find
that the rate for bound state formation is suppressed relative to direct
annihilation, and so provides only a small correction to the overall
annihilation rate. The soft photons radiated by the capture process and by
bound state transitions could permit measurement of the dark matter's quantum
numbers; for wino-like dark matter, such photons are rare, but might be
observable by a future ground-based gamma-ray telescope combining large
effective area and a low energy threshold.Comment: 3rd version. An interference sign fixed and changes propagated
through the paper. Topline qualitative conclusions unchange
Non-classical photon streams using rephased amplified spontaneous emission
We present a fully quantum mechanical treatment of optically rephased photon
echoes. These echoes exhibit noise due to amplified spontaneous emission,
however this noise can be seen as a consequence of the entanglement between the
atoms and the output light. With a rephasing pulse one can get an "echo" of the
amplified spontaneous emission, leading to light with nonclassical correlations
at points separated in time, which is of interest in the context of building
wide bandwidth quantum repeaters. We also suggest a wideband version of DLCZ
protocol based on the same ideas.Comment: 5 pages, 4 figures. Added section
Anterior cruciate ligament reconstruction with bone-patellar tendon-bone autograft versus allograft in young patients
Objectives: Traditionally, bone-patella tendon-bone (BTB) autograft has been the gold standard graft choice for younger, athletic patients requiring ACL reconstruction. However, donor site morbidity, post-operative patella fracture, and increased operative time have led many surgeons to choose BTB allograft for their reconstructions. Opponents of allografts feel that slower healing time, higher rate of graft failure, and potential for disease transmission makes them undesirable graft choices in athletic patients. The purpose of this study is to evaluate the clinical outcomes, both subjective and objective, of young patients that who have undergone either BTB autograft or allograft reconstructions with a minimum of 2-year follow-up. Methods: One hundred and twenty patients (60 autograft, 60 allograft), age 25 and below at time of surgery, were contacted after being retrospectively identified as patients having an ACL reconstruction with either a BTB allograft or autograft by one senior surgeon. Patients were administered the Lysholm Knee Scoring Scale and IKDC Subjective Knee Evaluation questionnaires. Fifty (25 BTB autograft and 25 BTB allograft) of the 120 returned for physical examination as well as completion of a single leg hop test and laxity evaluation using a KT-1000 arthrometer evaluation. Of the 120 patients contacted, there were a total of 7 failures (5.8%) requiring revision, 6 in the allograft group (86%) and 1 in the autograft group (14%). Results: The average Lysholm scores were 89.0 and 89.56 and the average IKDC scores were 90.8 and 92.1 in the autograft and allograft groups respectively. The differences in the Lysholm scores and the IKDC scores were not significant. The single leg hop and KT-1000 scores were also not significantly different. One autograft patient had a minor motion deficit. Three allograft patients had a grade 1 Lachman and pivot glide. One autograft patient and two allograft patients had mild patellafemoral crepitus. There was no significant difference in anterior knee pain between the two groups Conclusion: There is no significant difference in patient-rated outcome between ACL reconstructions using BTB autografts versus allografts. However, the overall study group did reveal an increased failure rate requiring revision in the allograft group. Ā© The Author(s) 2015
- ā¦