202 research outputs found
A symbol of infinite (be)longing: Psychosocial rhythms of inclusion and exclusion at South African universities
This paper argues that the life histories of Black South African women scientists provide a telling story of psychosocial (trans)formation because they experience the world as outliers; paradoxically positioned within an interstitial âzone of (non)beingâ between their dual sense of inclusion in and exclusion from marginal and dominant groups. Using a narrative method to enquire into the lives of fourteen scholarship students in Science, Technology, Engineering, and Mathematics (STEM) fields at a historically white South African university (HWU), this paper proposes an infinity model to illustrate how these young women locate their-selves in the field of higher education through recognition, dislocate their-selves from the field through misrecognition and infinitely recreate new subjectivities and epistemic communities at the intersecting space in between inclusion-exclusion.
Hard x-ray broad band Laue lenses (80 - 600 keV): building methods and performances
We present the status of the laue project devoted to develop a technology for
building a 20 meter long focal length Laue lens for hard x-/soft gamma-ray
astronomy (80 - 600 keV). The Laue lens is composed of bent crystals of Gallium
Arsenide (GaAs, 220) and Germanium (Ge, 111), and, for the first time, the
focusing property of bent crystals has been exploited for this field of
applications. We show the preliminary results concerning the adhesive employed
to fix the crystal tiles over the lens support, the positioning accuracy
obtained and possible further improvements. The Laue lens petal that will be
completed in a few months has a pass band of 80 - 300 keV and is a fraction of
an entire Laue lens capable of focusing X-rays up to 600 keV, possibly
extendable down to 20 - 30 keV with suitable low absorption crystal materials
and focal length. The final goal is to develop a focusing optics that can
improve the sensitivity over current telescopes in this energy band by 2 orders
of magnitude
The LAUE project for broadband gamma-ray focusing lenses
We present the LAUE project devoted to develop an advanced technology for
building a high focal length Laue lens for soft gamma--ray astronomy (80-600
keV). The final goal is to develop a focusing optics that can improve the
current sensitivity in the above energy band by 2 orders of magnitude.Comment: 7 pages, 6 figures, presented at the SPIE conference on "Optics for
EUV, X-ray, and Gamma-ray Astronomy". To be published in the Proceedings of
SPIE, vol.8147, 201
Coulomb-gas formulation of SU(2) branes and chiral blocks
We construct boundary states in WZNW models using the bosonized
Wakimoto free-field representation and study their properties. We introduce a
Fock space representation of Ishibashi states which are coherent states of
bosons with zero-mode momenta (boundary Coulomb-gas charges) summed over
certain lattices according to Fock space resolution of . The Virasoro
invariance of the coherent states leads to families of boundary states
including the B-type D-branes found by Maldacena, Moore and Seiberg, as well as
the A-type corresponding to trivial current gluing conditions. We then use the
Coulomb-gas technique to compute exact correlation functions of WZNW primary
fields on the disk topology with A- and B-type Cardy states on the boundary. We
check that the obtained chiral blocks for A-branes are solutions of the
Knizhnik-Zamolodchikov equations.Comment: 14 pages, 3 figures, revtex4. Essentially the published versio
Importance of spinal deformity index in risk evaluation of VCF (vertebral compression fractures) in obese subjects: prospective study.
Introduction
Obesity and osteoporosis share many features and recent studies have identified many similarities suggesting common pathophysiological mechanisms. Obesity is associated with a higher risk of non-traumatic fractures despite bone mineral density (BMD) being normal or even increased.
Materials and methods
54 obese subjects were analyzed (51 ± 16 years, 10 males, 44 females). Spinal deformity index (SDI) is a semi-quantitative method that may be a surrogate index of bone microarchitecture. SDI index was higher in patients than in controls. In 87.5 % of patients and 10 % of controls we found morphometric vertebral fractures, despite a DEXA Tscore not diagnostic of osteoporosis.
Conclusion
The objective of this study was to assess in obese patients levels of 25OH vitamin D, parathyroid hormone, serum and urinary calcium (Ca) and phosphorus (P), BMD, and SDI. 87.5 % of the obese subjects present nontraumatic vertebral fractures and reduced bone quality as measured by SDI
Development status of the LAUE project
We present the status of LAUE, a project supported by the Italian Space
Agency (ASI), and devoted to develop Laue lenses with long focal length (up to
100 meters), for hard X--/soft gamma--ray astronomy (80-600 keV). Thanks to
their focusing capability, the design goal is to improve the sensitivity of the
current instrumention in the above energy band by 2 orders of magnitude, down
to a few times photons/(cm s keV).Comment: 9 pages, 9 figures, presented at the Space Telescopes and
Instrumentation Symposium in Amsterdam, 2012: Ultraviolet to Gamma Ray
Conference. Published in the Proceedings of the SPIE, Volume 8443, id.
84430B-84430B-9 (2012
Predictors of short-term readmission after beyond total mesorectal excision for primary locally advanced and recurrent rectal cancer
Unplanned readmissions heavily affect the cost of health care and are used as an indicator of performance. No clear data are available regarding beyond-total mesorectal excision (bTME) procedure. Aim of the study is to identify patient-related and surgery-related factors influencing the 30-day readmissions after bTME. Retrospective data were collected from 220 patients who underwent bTME procedures at single centre between 2006 and 2016. Patient-related and operative factors were assessed, including body mass index (BMI), age, gender, American Society of Anaesthesiologistsâ (ASA) score, preoperative stage, neo-adjuvant therapy, primary tumour vs recurrence, the extent of surgery. The readmission rate was 8.18%. No statistically significant association was found with BMI, ASA score, length of stay and stay in the intensive care unit, primary vs recurrent tumour or blood transfusions. Not quite statistically significant was the association with pelvic side wall dissection (OR 3.32, p = 0.054). Statistically significant factors included preoperative stage > IIIb (OR: 4.77, p = 0.002), neo-adjuvant therapy (OR: 0.13, p = 0.0006), age over 65 years (OR: 5.96, p = 0.0005), any re-intervention during the first admission (OR: 7.4, p = 0.0001), and any post-operative complication (OR: 9.01, p = 0.004). The readmission rate after beyond-TME procedure is influenced by patient-related factors as well as post-operative morbidity
N=1* model and glueball superpotential from Renormalization-Group-improved perturbation theory
A method for computing the low-energy non-perturbative properties of SUSY
GFT, starting from the microscopic lagrangian model, is presented. The method
relies on covariant SUSY Feynman graph techniques, adapted to low energy, and
Renormalization-Group-improved perturbation theory. We apply the method to
calculate the glueball superpotential in N=1 SU(2) SYM and obtain a potential
of the Veneziano-Yankielowicz type.Comment: 19 pages, no figures; added references; note added at the end of the
paper; version to appear in JHE
Wrapped Magnetized Branes: Two Alternative Descriptions?
We discuss two inequivalent ways for describing magnetized D-branes wrapped N
times on a torus T^2. The first one is based on a non-abelian gauge bundle
U(N), while the second one is obtained by means of a Narain T-duality
transformation acting on a theory with non-magnetized branes. We construct in
both descriptions the boundary state and the open string vertices and show that
they give rise to different string amplitudes. In particular, the description
based on the gauge bundle has open string vertex operators with momentum
dependent Chan-Paton factors.Comment: 60 pages, LaTe
The geometry of the limit of N=2 minimal models
We consider the limit of two-dimensional N=(2,2) superconformal minimal
models when the central charge approaches c=3. Starting from a geometric
description as non-linear sigma models, we show that one can obtain two
different limit theories. One is the free theory of two bosons and two
fermions, the other one is a continuous orbifold thereof. We substantiate this
claim by detailed conformal field theory computations.Comment: 35 pages, 3 figures; v2 minor corrections, version to be published in
J. Phys.
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