764 research outputs found
Eosinophilic Granuloma of the Spine With and Without Vertebra Plana: Long-term Follow-up of Six Cases (Cast Reports)
Vertebral eosinophilic granuloma is a rare condition frequently associated with
vertebra plana. In this paper we present six patients with eosinophilic granuloma
of the spine; three were without vertebra plana, which represents a diagnostic
problem. The mean follow-up was 9 years, (range 2 to 23) and the mean age was
10.8 years at diagnosis. All complained of pain with no neurological deficit. The
lesions were located on the vertebral bodies of C4, T9, T10, L1, L2, and L5,
respectively. Histologic confirmation of diagnosis was obtained in all patients,
two by puncture and four by open biopsy. The patients with vertebra plana (T10,
L1, and L5, respectively) were treated conservatively. Long-term follow-up
demonstrated total healing of the vertebral body in two and partial rebuilding 8
years after diagnosis in one. Patients without vertebra plana (C4, T9, and L2,
respectively) underwent curettage and bone grafting. In the patient with T9
location, a T8-10 anterior arthrodesis with autogenous rib graft was performed.
The outcome was satisfactory in all
Lack of uniqueness for weak solutions of the incompressible porous media equation
In this work we consider weak solutions of the incompressible 2-D porous
media equation. By using the approach of De Lellis-Sz\'ekelyhidi we prove
non-uniqueness for solutions in in space and time.Comment: 23 pages, 2 fugure
Rechargeable Lithium-Ion Battery Based on a Cathode of Copper Hexacyanoferrate
In this work, the performance of copper(II) hexacyanoferrate(III) (CuHCF) as a cathode material for lithium-ion batteries was studied. The compound was synthesized by a precipitation reaction in aqueous solution in a closed system. The morphology and structure show nanoparticles with sizes between 40 and 70 nm with a high agglomeration and a crystalline phase with a cubic structure, respectively. The material exhibited a stable performance with a working potential of around 3.6 V vs Li+/Li and a decrease in the charge transfer resistance due to increased ionic conductivity. The gravimetric capacity obtained is near 60 mAh g−1 during 300 cycles at a rate of C/20, close to the practical capacity. Considering its electrochemical performance, CuHCF could be a promising cathode material for lithium-ion batteries
Paleoclimate reconstruction of the last 36 kyr based on branched glycerol dialkyl glycerol tetraethers in the Padul palaeolake record (Sierra Nevada, southern Iberian Peninsula)
Quantitative continental climate reconstructions covering the last glacial cycle from the Iberian Peninsula are scarce. In order to fill this gap, we obtained for the first time a high-resolution mean annual air temperature (MAAT) record based on the distribution of specific bacterial membrane lipids (i.e., branched glycerol dialkyl glycerol tetraethers; brGDGTs) from the last 36.0-4.7 kyr palaeolake record recovered by the Padul-15-05 sedimentary core (Padul, Sierra Nevada, southern Iberia). The fractional abundance of the three major groups of GDGTs present in the Padul sediments, GDGT-0, crenarchaeol and the summed brGDGTs, is comparable with that of other shallow and small (Peer reviewe
Phenomenological constraints on SUSY SU(5) GUTs with non-universal gaugino masses
We study phenomenological aspects of supersymmetric SU(5) grand unified
theories with non-universal gaugino masses. For large tan beta, we investigate
constraints from the requirement of successful electroweak symmetry breaking,
the positivity of stau mass squared and the b to s gamma decay rate. In the
allowed region, the nature of the lightest supersymmetric particle is
determined. Examples of mass spectra are given. We also calculate loop
corrections to the bottom mass due to superpartners.Comment: 10 pages, 2 figures (8 eps files), uses REVTeX. Replaced to match the
version to be published in PRD: minor corrections and addition
Histiocitosis X
Presentamos una revisión bibliográfica y de nuestra experiencia clínica en el diagnóstico y tratamiento de la Histiocitosis X, término que engloba el granuloma eosinófilo, el síndrome de Hand-Schüller-Christian y el síndrome de Letterer-Siwe. Tuvimos un total de 28 casos, con un promedio de edad de 11.8 años y una distribución por sexo de 18 (64%) hombres y 10 (36%) mujeres. De los casos estudiados, 17 lesiones fueron solitarias y 8 pacientes tuvieron lesiones óseas múltiples. Tres pacientes padecieron formas diseminadas de la enfermedad. De éstos, dos eran síndrome de Hand-Schüller-Christian y uno de Letterer-Siwe. La localización más frecuente fue el fémur en los pacientes con localización ósea solitaria y el cráneo en los de localización ósea múltiple. El número total de lesiones fue de 47. El tratamiento aplicado dependió del tipo de localización, la forma clínica y el número de lesiones. Los pacientes con localización ósea solitaria (17) fueron tratados con legrado e injerto en 6 casos, resección segmentaria en 3, legrado en otros 3, radioterapia en 1 y 4 pacientes no recibieron tratamiento. Los pacientes con lesiones óseas múltiples (8) fueron tratados con cirugía en 4 ocasiones, radioterapia en 2, cirugía y radioterapia en 1 y, finalmente, un paciente no recibió tratamiento. Las formas diseminadas fueron tratadas con cirugía de la lesión principal dependiendo de las manifestaciones clínicas, así como quimioterapia y radioterapia.
El pronóstico de casi todos los casos estudiados fue bueno, observándose regresión de la enfermedad incluso sin tratamiento específico. El caso de enfermedad diseminada aguda tipo Letterer-Siwe falleció por las complicaciones generales propias de la enfermedad
Flavour Violation in SUSY SU(5) GUT at Large tan beta
We study flavour violation in the minimal SUSY SU(5) GUT assuming all the
third generation Yukawa couplings to be due to the renormalizable physics above
GUT scale. At large as suggested by Yukawa unification in SU(5),
sizable flavour violation in the left (right) slepton (down squark) sector is
induced due to renormalization effects of down type Yukawa couplings between
GUT and Planck scales in addition to the flavour violation in the right slepton
sector. The new flavour physics contribution to mixing
is small but might be of phenomenological interest in the case of The sign of the latter contribution is the same as the sign of the
dominant chargino contribution, thus making the constraints on SUSY scale
coming from somewhat more restrictive. The most important
feature of the considered scenario is the large rate of lepton flavour
violation. Given the present experimental constraints, the and
conversion branching ratios are above the sensitivity of the planned
experiments unless the SUSY scale is pushed above one TeV.Comment: 22 pages, 7 figure
Charge asymmetries in e+e- -> pi+ pi- gamma at the phi resonance
We consider the forward-backward pion charge asymmetry for the
e^{+}e^{-}\to\pi^{+}\pi^{-}\gamma process. At tree level we consider
bremsstrahlung and double resonance contributions. Although the latter
contribution is formally sub-leading, it is enhanced at low dipion invariant
mass due to resonant effects. We consider also four alternative models
to describe the final state radiation at the loop level: Resonance Chiral
Perturbation Theory, Unitarized Chiral Perturbation Theory, Kaon Loop Model and
Linear Sigma Model. The last three models yield results compatible with
experimental data. The Kaon Loop Model requires an energy dependent phase to
achieve the agreement.Comment: Revised version, conclusions changed, 11 pages, 8 figs, version to
appear in PL
Paleoclimate reconstruction of the last 36 kyr based on branched glycerol dialkyl glycerol tetraethers in the Padul palaeolake record (Sierra Nevada, southern Iberian Peninsula)
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