3,308 research outputs found
Dermatophyte Morphology: A Scanning Electron Microscopy Study
The Dermatophytes are a broad group of fungi belonging to the class Fungii imperfecti that are the causative agents of dermophytosis (ringworm infections). The present work offers an overview of the morphology of these fungi found in cultures according to the scanning electron microscope. The fungi were obtained from cultures left to develop over variable periods of time that would be sufficient for growth. The morphological features of some dermatophytes obtained in artificial cultures are detailed: M. canis, M. gypseum, M. audouini, M. cookei, T. mentagrophytes, T. schoulemu, T. verrucosuin, T. ajelloi, T. prohferans, and E. floccosum. In all cases an analysis of the morphology of the reproductive mycelium developed in the culture was made: hyphae, macroconidia, microconidia, and chlamydospores; details that serve to distinguish one fungus from another. In the perfect forms, the morphology of the peridial hyphae and of the ascocarps (cleistotethia) are described
Carrier and Light Trapping in Graded Quantum Well Laser Structures
We investigated the carrier and light trapping in GaInAs/AlGaAs single
quantum well laser structures by means of time resolved photoluminescence and
Raman spectroscopy. The influence of the shape and depth of the confinement
potential and of the cavity geometry was studied by using different AlGaAs/GaAs
short-period superlattices as barriers. Our results show that grading the
optical cavity improves considerably both carrier and light trapping in the
quantum well, and that the trapping efficiency is enhanced by increasing the
graded confining potential.Comment: PDF-format, 15 pages (including 4 figures), Applied Physics Letters
(June 2000
Crossover from Electronic to Atomic Shell Structure in Alkali Metal Nanowires
After making a cold weld by pressing two clean metal surfaces together, upon
gradually separating the two pieces a metallic nanowire is formed, which
progressively thins down to a single atom before contact is lost. In previous
experiments [1,2] we have observed that the stability of such nanowires is
influenced by electronic shell filling effects, in analogy to shell effects in
metal clusters [3]. For sodium and potassium at larger diameters there is a
crossover to crystalline wires with shell-closings corresponding to the
completion of additional atomic layers. This observation completes the analogy
between shell effects observed for clusters and nanowires.Comment: 4 page
Self-Contempt, the Working Alliance and Outcome in Treatments for Borderline Personality Disorder: An Exploratory Study.
Objective. We examined the role of expressed self-contempt in therapy for borderline personality disorder (BPD). Based on previous literature on BPD, we assumed an association between the self-contempt and the core symptoms of BPD. We also studied the progression of expressed self-contempt during the treatment and its effect on the alliance and the outcomes of treatment.Method. We rated the expressed self-contempt in 148 tape-recorded sessions with patients with BPD (N = 50), during a brief psychiatric treatment. We rated self-contempt at three time-points, using an observer-rate scale. Self-reported questionnaires were used to assess symptoms and the working alliance.Results. There are some associations between self-contempt and BPD symptoms. Expressed self-contempt did not change during the treatment. One measure of self-contempt was associated with a weaker alliance rated by the patients and with a stronger alliance rated by the therapists. The expression of high self-contempt was not predictive of outcomes when the initial level of problems was controlled for.Conclusions. The results highlight the importance to examine the complex effects of self-contempt in BPD undergoing treatment in a differentiated manner and suggest to clinicians and researchers to be attentive to this specific emotional state, and change therein, in psychotherapy.Keywords: Self-contempt; Borderline Personality Disorder; Brief Treatment; Therapeutic Alliance; EmotionTrial registration: ClinicalTrials.gov identifier: NCT01896024
Crystallization Kinetics of LaF3 Nanocrystals in an Oxyfluoride Glass
Nanocrystallization of LaF3 in a glass of composition 55SiO2–
20Al2O3–15Na2O–10LaF3 (mol%) has been achieved by heat
treatment above the glass transition temperature. A maximum
crystal size of 14 nm has been attained, with the crystalline
fraction and crystal size dependent on the time and temperature
of thermal treatment. The effect of lanthanum fluoride crystallization
is noticeable from the microstructural and compositional
changes in the glass matrix, which have been studied using
several techniques, including viscosity, dilatometry, X-ray diffraction,
and quantitative Rietveld refinement, transmission
electron microscopy, and differential scanning calorimetry.
The crystallization mechanism is shown to occur via regions of
La- and Si-phase separation in the glass, from which the fluoride
crystals develop during heat treatment. The interface between
the glass matrix and the crystals in the demixed ranges is
enriched in network formers, mainly SiO2, creating a viscous
barrier, which inhibits further crystal growth and limits the
crystal size to the nanometric range.Peer reviewe
Single Cord Blood Combined with HLA-Mismatched Third Party Donor Cells: Comparable Results to Matched Unrelated Donor Transplantation in High-Risk Patients with Hematologic Disorders
AbstractMatched unrelated donor (MUD) transplantation is the first alternative in the absence of a matched sibling donor. For patients without a suitable adult donor, we have adopted the dual stem cell transplantation protocol consisting of cord blood (CB) in combination with CD34+ cells from a third party HLA-mismatched donor. We analyzed the outcomes of patients undergoing both procedures in a single center. Starting in 2004, a total of 20 patients with high-risk disease underwent 22 dual transplants and 25 patients underwent myeloablative MUD transplantation. The 30-day cumulative incidence of neutrophil engraftment was similar in both groups (91% and 95%), with a median time to engraftment of 14 and 16 days, respectively. Grade II-IV acute graft-versus-host disease was more frequent in the MUD group (40% versus 5%). Except for a tendency toward a higher incidence of viral hemorrhagic cystitis in the dual transplantation group, posttransplantation infectious events were comparable in the 2 groups. The 3-year cumulative incidence rates of relapse (41% versus 44%) and nonrelapse mortality (30% versus 25%) were similar in the MUD and dual transplantation cohorts. Estimated 3-year overall survival and disease-free survival were 47% and 41%, respectively, with no survival advantage for either group. In our experience, dual transplantation offers survival rates comparable to those from myeloablative MUD transplantation with similar nonrelapse mortality rates
Stiff monatomic gold wires with a spinning zigzag geometry
Using first principles density functional calculations, gold monatomic wires
are found to exhibit a zigzag shape which remains under tension, becoming
linear just before breaking. At room temperature they are found to spin, what
explains the extremely long apparent interatomic distances shown by electron
microscopy.The zigzag structure is stable if the tension is relieved, the wire
holding its chainlike shape even as a free-standing cluster. This unexpected
metallic-wire stiffness stems from the transverse quantization in the wire, as
shown in a simple free electron model.Comment: 4 pages, latex, 5 figures, submitted to PR
NLO BFKL Equation, Running Coupling and Renormalization Scales
I examine the solution of the BFKL equation with NLO corrections relevant for
deep inelastic scattering. Particular emphasis is placed on the part played by
the running of the coupling. It is shown that the solution factorizes into a
part describing the evolution in Q^2, and a constant part describing the input
distribution. The latter is infrared dominated, being described by a coupling
which grows as x decreases, and thus being contaminated by infrared
renormalons. Hence, for this part we agree with previous assertions that
predictive power breaks down for small enough x at any Q^2. However, the former
is ultraviolet dominated, being described by a coupling which falls like
1/(\ln(Q^2/\Lambda^2) + A(\bar\alpha_s(Q^2)\ln(1/x))^1/2)with decreasing x, and
thus is perturbatively calculable at all x. Therefore, although the BFKL
equation is unable to predict the input for a structure function for small x,
it is able to predict its evolution in Q^2, as we would expect from the
factorization theory. The evolution at small x has no true powerlike behaviour
due to the fall of the coupling, but does have significant differences from
that predicted from a standard NLO in alpha_s treatment. Application of the
resummed splitting functions with the appropriate coupling constant to an
analysis of data, i.e. a global fit, is very successful.Comment: Tex file, including a modification of Harvmac, 46 pages, 8 figures as
.ps files. Correction of typos, updating of references, very minor
corrections to text and fig.
From favorable atomic configurations to supershell structures: a new interpretation of conductance histograms
Title: From favorable atomic configurations to supershell structures: a new
interpretation of conductance histograms Authors: A. Hasmy (IVIC), E. Medina
(IVIC), P.A. Serena (CSIC,IVIC) Comments: 7 pages, 3 figures,
cond-mat.anwar.10825 Subj-class: Soft Condensed MatterComment: 7 pages, 3 figuresSubject: fput HMS.tex HMS-FIG1.ps HMS-FIG2.ps
HMS-FIG3.p
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