1,517 research outputs found
Rapid Lung Ultrasound COVID-19 Severity Scoring with Resource-Efficient Deep Feature Extraction
Artificial intelligence-based analysis of lung ultrasound imaging has been
demonstrated as an effective technique for rapid diagnostic decision support
throughout the COVID-19 pandemic. However, such techniques can require days- or
weeks-long training processes and hyper-parameter tuning to develop intelligent
deep learning image analysis models. This work focuses on leveraging
'off-the-shelf' pre-trained models as deep feature extractors for scoring
disease severity with minimal training time. We propose using pre-trained
initializations of existing methods ahead of simple and compact neural networks
to reduce reliance on computational capacity. This reduction of computational
capacity is of critical importance in time-limited or resource-constrained
circumstances, such as the early stages of a pandemic. On a dataset of 49
patients, comprising over 20,000 images, we demonstrate that the use of
existing methods as feature extractors results in the effective classification
of COVID-19-related pneumonia severity while requiring only minutes of training
time. Our methods can achieve an accuracy of over 0.93 on a 4-level severity
score scale and provides comparable per-patient region and global scores
compared to expert annotated ground truths. These results demonstrate the
capability for rapid deployment and use of such minimally-adapted methods for
progress monitoring, patient stratification and management in clinical practice
for COVID-19 patients, and potentially in other respiratory diseases.Comment: Accepted to ASMUS 2022 Workshop at MICCA
Migration of silicone gel into breast parenchyma following mammary prosthesis rupture
The case report of a patient with a ruptured gel mammary prosthesis complicated by migration of the gel into the breast parenchyma is presented. It is felt that the constant massage of the prostheses in an attempt to avoid fibrous contracture after closed capsulotomy is the etiology for this migration. The prosthesis and extruded gel were removed by sacrificing breast parenchyma. Repeated prosthesis massage after closed capsulotomy exposes the patient to significant potential complication if the prosthesis has been ruptured.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48160/1/266_2005_Article_BF01570670.pd
Size distribution of magnetic charge domains in thermally activated but out-of-equilibrium artificial spin ice
International audienceA crystal of emerging magnetic charges is expected in the phase diagram of the dipolar kagome spin ice. An observation of charge crystallites in thermally demagnetized artificial spin ice arrays has been recently reported by S. Zhang and coworkers and explained through the thermodynamics of the system as it approaches a charge-ordered state. Following a similar approach, we have generated a partial order of magnetic charges in an artificial kagome spin ice lattice made out of ferrimagnetic material having a Curie temperature of 475 K. A statistical study of the size of the charge domains reveals an unconventional sawtooth distribution. This distribution is in disagreement with the predictions of the thermodynamic model and is shown to be a signature of the kinetic process governing the remagnetization
Unified N=2 Maxwell-Einstein and Yang-Mills-Einstein Supergravity Theories in Four Dimensions
We study unified N=2 Maxwell-Einstein supergravity theories (MESGTs) and
unified Yang-Mills Einstein supergravity theories (YMESGTs) in four dimensions.
As their defining property, these theories admit the action of a global or
local symmetry group that is (i) simple, and (ii) acts irreducibly on all the
vector fields of the theory, including the ``graviphoton''. Restricting
ourselves to the theories that originate from five dimensions via dimensional
reduction, we find that the generic Jordan family of MESGTs with the scalar
manifolds [SU(1,1)/U(1)] X [SO(2,n)/SO(2)X SO(n)] are all unified in four
dimensions with the unifying global symmetry group SO(2,n). Of these theories
only one can be gauged so as to obtain a unified YMESGT with the gauge group
SO(2,1). Three of the four magical supergravity theories defined by simple
Euclidean Jordan algebras of degree 3 are unified MESGTs in four dimensions.
Two of these can furthermore be gauged so as to obtain 4D unified YMESGTs with
gauge groups SO(3,2) and SO(6,2), respectively. The generic non-Jordan family
and the theories whose scalar manifolds are homogeneous but not symmetric do
not lead to unified MESGTs in four dimensions. The three infinite families of
unified five-dimensional MESGTs defined by simple Lorentzian Jordan algebras,
whose scalar manifolds are non-homogeneous, do not lead directly to unified
MESGTs in four dimensions under dimensional reduction. However, since their
manifolds are non-homogeneous we are not able to completely rule out the
existence of symplectic sections in which these theories become unified in four
dimensions.Comment: 47 pages; latex fil
Privacy-Preserving Computation of Disease Risk by Using Genomic, Clinical, and Environmental Data (poster version)
Privacy-Preserving Computation of Disease Risk by Using Genomic, Clinical, and Environmental Dat
Heterotic domain wall solutions and SU(3) structure manifolds
We examine compactifications of heterotic string theory on manifolds with
SU(3) structure. In particular, we study N = 1/2 domain wall solutions which
correspond to the perturbative vacua of the 4D, N =1 supersymmetric theories
associated to these compactifications. We extend work which has appeared
previously in the literature in two important regards. Firstly, we include two
additional fluxes which have been, heretofore, omitted in the general analysis
of this situation. This allows for solutions with more general torsion classes
than have previously been found. Secondly, we provide explicit solutions for
the fluxes as a function of the torsion classes. These solutions are
particularly useful in deciding whether equations such as the Bianchi
identities can be solved, in addition to the Killing spinor equations
themselves. Our work can be used to straightforwardly decide whether any given
SU(3) structure on a six-dimensional manifold is associated with a solution to
heterotic string theory. To illustrate how to use these results, we discuss a
number of examples taken from the literature.Comment: 34 pages, minor corrections in second versio
The effective action of D6-branes in N=1 type IIA orientifolds
We use a Kaluza-Klein reduction to compute the low-energy effective action
for the massless modes of a spacetime-filling D6-brane wrapped on a special
Lagrangian 3-cycle of a type IIA Calabi-Yau orientifold. The modifications to
the characteristic data of the N=1 bulk orientifold theory in the presence of a
D6-brane are analysed by studying the underlying Type IIA supergravity coupled
to the brane worldvolume in the democratic formulation and performing a
detailed dualisation procedure. The N=1 chiral coordinates are found to be in
agreement with expectations from mirror symmetry. We work out the Kahler
potential for the chiral superfields as well as the gauge kinetic functions for
the bulk and the brane gauge multiplets including the kinetic mixing between
the two. The scalar potential resulting from the dualisation procedure can be
formally interpreted in terms of a superpotential. Finally, the gauging of the
Peccei-Quinn shift symmetries of the complex structure multiplets reproduces
the D-term potential enforcing the calibration condition for special Lagrangian
3-cycles.Comment: 48 pages, v2: typos corrected, references adde
Systemic lupus erythematosus induced by anti-tumour necrosis factor alpha therapy: a French national survey
The development of drug-induced lupus remains a matter of concern in patients treated with anti-tumour necrosis factor (TNF) alpha. The incidence of such adverse effects is unknown. We undertook a retrospective national study to analyse such patients. Between June and October 2003, 866 rheumatology and internal medicine practitioners from all French hospital centres prescribing anti-TNF in rheumatic diseases registered on the website of the 'Club Rhumatismes et Inflammation' were contacted by email to obtain the files of patients with TNF-induced systemic lupus erythematosus. Twenty-two cases were collected, revealing two aspects of these manifestations. Ten patients (six patients receiving infliximab, four patients receiving etanercept) only had anti-DNA antibodies and skin manifestations one could classify as 'limited skin lupus' or 'toxidermia' in a context of autoimmunity, whereas 12 patients (nine patients receiving infliximab, three patients receiving etanercept) had more complete drug-induced lupus with systemic manifestations and at least four American Congress of Rheumatology criteria. One patient had central nervous system manifestations. No patients had lupus nephritis. The signs of lupus occurred within a mean of 9 months (range 3–16 months) in patients treated with infliximab and within a mean of 4 months (range 2–5 months) in patients treated with etanercept. In all cases after diagnosis was determined, anti-TNF was stopped and specific treatment introduced in eight patients: two patients received intravenous methylprednisolone, four patients received oral steroids (15–35 mg/day), and two patients received topical steroids. Lupus manifestations abated within a few weeks (median 8 weeks, standard deviation 3–16) in all patients except one with longer-lasting evolution (6 months). At that time, cautious estimations (unpublished data from Schering Plough Inc. and Wyeth Inc.) indicated that about 7700 patients had been exposed to infliximab and 3000 to etanercept for inflammatory arthritides in France. It thus appears that no drug was more implicated than the other in lupus syndromes, whose incidence was 15/7700 = 0.19% with infliximab and 7/3800 = 0.18% with etanercept. Clinicians should be aware that lupus syndromes with systemic manifestations may occur in patients under anti-TNF alpha treatment
Medical services at the FIFA world cup Qatar 2022
Objective The Football World Cup is among the biggest sporting events in the world, but data to inform the requirements of medical care for such tournaments are limited. This study describes the athlete and team medical services at the FIFA World Cup Qatar 2022. Methods Three different medical service entities were identified through a needs analysis based on expert advice, team physician interviews and questionnaires prior to the event: 'Team Services' to provide any workforce or equipment needs of the teams, a 'Polyclinic' to manage any acute medical demands, and a 'recovery centre' to improve game readiness throughout the tournament. All services had been set up prior to the tournament and thoroughly tested. Results Of a total of 832 athletes, ∼1300 team delegation and ∼130 match officials, 167 individuals including 129 (77%) athletes and 38 (23%) non-athletes were assessed in the polyclinic. For the 129 athletes (median 4 players per team), medical imaging was the most requested service, which peaked during the group phase of the tournament. Most requests were received during normal working hours despite many games finishing late at night. 30 of the 32 participating teams solicited medical services for their players at least once. Three teams made use of the recovery facilities, and 17 teams requested additional medical equipment or clinical assistance. Conclusion Central imaging services was the most used medical resource at the FIFA World Cup Qatar 2022, and over half of teams required additional medical equipment or personnel. These data may inform planning of medical services for similar events in the future
Genomic aberrations associated with outcome in anaplastic oligodendroglial tumors treated within the EORTC phase III trial 26951
Despite similar morphological aspects, anaplastic oligodendroglial tumors (AOTs) form a heterogeneous clinical subgroup of gliomas. The chromosome arms 1p/19q codeletion has been shown to be a relevant biomarker in AOTs and to be perfectly exclusive from EGFR amplification in gliomas. To identify new genomic regions associated with prognosis, 60 AOTs from the EORTC trial 26951 were analyzed retrospectively using BAC-array-based comparative genomic hybridization. The data were processed using a binary tree method. Thirty-three BACs with prognostic value were identified distinguishing four genomic subgroups of AOTs with different prognosis (p < 0.0001). Type I tumors (25%) were characterized by: (1) an EGFR amplification, (2) a poor prognosis, (3) a higher rate of necrosis, and (4) an older age of patients. Type II tumors (21.7%) had: (1) loss of prognostic BACs located on 1p tightly associated with 19q deletion, (2) a longer survival, (3) an oligodendroglioma phenotype, and (4) a frontal location in brain. Type III AOTs (11.7%) exhibited: (1) a deletion of prognostic BACs located on 21q, and (2) a short survival. Finally, type IV tumors (41.7%) had different genomic patterns and prognosis than type I, II and III AOTs. Multivariate analysis showed that genomic type provides additional prognostic data to clinical, imaging and pathological features. Similar results were obtained in the cohort of 45 centrally reviewed–validated cases of AOTs. Whole genome analysis appears useful to screen the numerous genomic abnormalities observed in AOTs and to propose new biomarkers particularly in the non-1p/19q codeleted AOTs
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