1,141 research outputs found
Association between obstructive apnea syndrome during sleep and damages to anterior labyrinth: Our experience
The obstructive sleep apnea syndrome is a chronic condition characterized by frequent episodes of collapse of the upper airways during sleep. It can be considered a multisystem disease. Among the districts involved, even the auditory system was seen to be concerned. It was enrolled a population of 20 patients after polysomnographic diagnosis of OSAS (Apnea Hypopnea Index > 10) and a control group of 28 healthy persons (Apnea Hypopnea Index < 5). Each patient has been subjected to Pure Tone Audiometry, Tympanometry, study of Acoustic Reflex, Otoacoustic Emissions and Auditory Brainstem Response. Moreover they were submitted to endoscopy of upper airway with Muller Maneuver and Epworth Sleepiness Scale (ESS). The values of ESS was 13.5 in OSAS group and 5.4 in control group. The tone audiometry is worse in all frequencies analyzed in OSAS patients, but within the normal range for both groups analyzed by 250 to 1000 Hertz. Otoacoustic emissions show a reduced reproducibility and a lower signal/ noise ratio in OSAS group (P <0.01)
A logic for reasoning about knowledge of unawareness
In the most popular logics combining knowledge and awareness, it is not possible to express statements about knowledge of unawareness such as “Ann knows that Bill is aware of something Ann is not aware of” – without using a stronger statement such as “Ann knows that Bill is aware of p and Ann is not aware of p”, for some particular p. In Halpern and Rêgo (2006, 2009b) (revisited in Halpern and Rêgo (2009a, 2013)) Halpern and Rêgo introduced a logic in which such statements about knowledge of unawareness can be expressed. The logic extends the traditional framework with quantification over formulae, and is thus very expressive. As a consequence, it is not decidable. In this paper we introduce a decidable logic which can be used to reason about certain types of unawareness. Our logic extends the traditional framework with an operator expressing full awareness, i.e., the fact that an agent is aware of everything, and another operator expressing relative awareness, the fact that one agent is aware of everything another agent is aware of. The logic is less expressive than Halpern’s and Rêgo’s logic. It is, however, expressive enough to express all of the motivating examples in Halpern and Rêgo (2006, 2009b). In addition to proving that the logic is decidable and that its satisfiability problem is PSPACE-complete, we present an axiomatisation which we show is sound and complete
Branching Structures in Elastic Shape Optimization
Fine scale elastic structures are widespread in nature, for instances in
plants or bones, whenever stiffness and low weight are required. These patterns
frequently refine towards a Dirichlet boundary to ensure an effective load
transfer. The paper discusses the optimization of such supporting structures in
a specific class of domain patterns in 2D, which composes of periodic and
branching period transitions on subdomain facets. These investigations can be
considered as a case study to display examples of optimal branching domain
patterns.
In explicit, a rectangular domain is decomposed into rectangular subdomains,
which share facets with neighbouring subdomains or with facets which split on
one side into equally sized facets of two different subdomains. On each
subdomain one considers an elastic material phase with stiff elasticity
coefficients and an approximate void phase with orders of magnitude softer
material. For given load on the outer domain boundary, which is distributed on
a prescribed fine scale pattern representing the contact area of the shape, the
interior elastic phase is optimized with respect to the compliance cost. The
elastic stress is supposed to be continuous on the domain and a stress based
finite volume discretization is used for the optimization. If in one direction
equally sized subdomains with equal adjacent subdomain topology line up, these
subdomains are consider as equal copies including the enforced boundary
conditions for the stress and form a locally periodic substructure.
An alternating descent algorithm is employed for a discrete characteristic
function describing the stiff elastic subset on the subdomains and the solution
of the elastic state equation. Numerical experiments are shown for compression
and shear load on the boundary of a quadratic domain.Comment: 13 pages, 6 figure
A Gamma-convergence argument for the blow-up of a non-local semilinear parabolic equation with Neumann boundary conditions
In this paper we study a simple non-local semilinear parabolic equation with
Neumann boundary condition. We give local existence result and prove global
existence for small initial data. A natural non increasing in time energy is
associated to this equation. We prove that the solution blows up at finite time
if and only if its energy is negative at some time before . The proof of
this result is based on a Gamma-convergence technique
Frontal brain asymmetries as effective parameters to assess the quality of audiovisual stimuli perception in adult and young cochlear implant users
How is music perceived by cochlear implant (CI) users? This question arises as "the next step" given the impressive performance obtained by these patients in language perception. Furthermore, how can music perception be evaluated beyond self-report rating, in order to obtain measurable data? To address this question, estimation of the frontal electroencephalographic (EEG) alpha activity imbalance, acquired through a 19-channel EEG cap, appears to be a suitable instrument to measure the approach/withdrawal (AW index) reaction to external stimuli. Specifically, a greater value of AW indicates an increased propensity to stimulus approach, and vice versa a lower one a tendency to withdraw from the stimulus. Additionally, due to prelingually and postlingually deafened pathology acquisition, children and adults, respectively, would probably differ in music perception. The aim of the present study was to investigate children and adult CI users, in unilateral (UCI) and bilateral (BCI) implantation conditions, during three experimental situations of music exposure (normal, distorted and mute). Additionally, a study of functional connectivity patterns within cerebral networks was performed to investigate functioning patterns in different experimental populations. As a general result, congruency among patterns between BCI patients and control (CTRL) subjects was seen, characterised by lowest values for the distorted condition (vs. normal and mute conditions) in the AW index and in the connectivity analysis. Additionally, the normal and distorted conditions were significantly different in CI and CTRL adults, and in CTRL children, but not in CI children. These results suggest a higher capacity of discrimination and approach motivation towards normal music in CTRL and BCI subjects, but not for UCI patients. Therefore, for perception of music CTRL and BCI participants appear more similar than UCI subjects, as estimated by measurable and not self-reported parameters
No phenotypic differences for polycystic ovary syndrome (PCOS) between women with and without type 1 diabetes mellitus.
CONTEXT: Women with type 1 diabetes mellitus (DM1) have a higher prevalence of polycystic ovary syndrome (PCOS) than the general population.
OBJECTIVE: The aim of this study was to clarify, in DM1 women with PCOS (PCOS-DM1), the influence of insulin therapy and glycemic control and evaluate the hormonal and phenotypic differences with age-matched and body mass index (BMI)-matched women with PCOS without diabetes.
DESIGN, SETTING, AND PATIENTS:
We evaluated 103 DM1 women with and without PCOS treated with intensive insulin therapy; 38 age-matched and BMI-matched women with PCOS without diabetes were compared in a cross-sectional study.
OUTCOME MEASUREMENTS:
Clinical, anthropometric, and metabolic parameters were evaluated. Hormonal evaluation and ovary ultrasound were performed during the follicular phase of the menstrual cycle.
RESULTS:
Applying the diagnostic criteria of the Androgen Excess Society, 38 (36.89%) women with DM1 showed PCOS. The 38 PCOS-DM1 women showed no differences in treatment and glycemic control compared with DM1 women without PCOS. The only difference was a higher visceral adiposity index in PCOS-DM1 (1.21±0.70 vs 0.90±0.32; P=.002). PCOS-DM1 showed no phenotypic differences with age-matched and BMI-matched PCOS without diabetes. The hormonal pattern was similar except that higher levels of Δ4androstenedione were found in PCOS-DM1 (12.89±3.49 vs 2.79±1.75 nmol/L; P=.010).
CONCLUSIONS:
The women with PCOS-DM1 do not exhibit particular phenotypic characteristics compared with nondiabetic women with PCOS. However, this pathological disorder must not be underestimated because it could be an additional cardiovascular risk factor in women with DM1
Tightness for a stochastic Allen--Cahn equation
We study an Allen-Cahn equation perturbed by a multiplicative stochastic
noise which is white in time and correlated in space. Formally this equation
approximates a stochastically forced mean curvature flow. We derive uniform
energy bounds and prove tightness of of solutions in the sharp interface limit,
and show convergence to phase-indicator functions.Comment: 27 pages, final Version to appear in "Stochastic Partial Differential
Equations: Analysis and Computations". In Version 4, Proposition 6.3 is new.
It replaces and simplifies the old propositions 6.4-6.
Therapeutic sequences in patients with grade 1−2 neuroendocrine tumors (NET): an observational multicenter study from the ELIOS group
Purpose: Many different treatments are suggested by guidelines to treat grade 1−2 (G1−G2) neuroendocrine tumors (NET). However, a precise therapeutic algorithm has not yet been established. This study aims at identifying and comparing the main therapeutic sequences in G1−G2 NET. Methods: A retrospective observational Italian multicenter study was designed to collect data on therapeutic sequences in NET. Median progression-free survival (PFS) was compared between therapeutic sequences, as well as the number and grade of side effects and the rate of dose reduction/treatment discontinuation. Results: Among 1182 patients with neuroendocrine neoplasia included in the ELIOS database, 131 G1–G2 gastroenteropancreatic, lung and unknown primary NET, unresectable or persistent/relapsing after surgery, treated with ≥2 systemic treatments, were included. Four main therapeutic sequences were identified in 99 patients: (A) somatostatin analogs (SSA) standard dose to SSA high dose (n = 36), (B) SSA to everolimus (n = 31), (C) SSA to chemotherapy (n = 17), (D) SSA to peptide receptor radionuclide therapy (PRRT) (n = 15). Median PFS of the second-line treatment was not reached in sequence A, 33 months in sequence B, 20 months in sequence C, 30 months in sequence D (p = 0.16). Both total number and severity of side effects were significantly higher in sequences B and C than A and D (p = 0.04), as well as the rate of dose reduction/discontinuation (p = 0.03). Conclusions: SSA followed by SSA high dose, everolimus, chemotherapy or PRRT represent the main therapeutic sequences in G1−G2 NET. Median PFS was not significantly different between sequences. However, the sequences with SSA high dose or PRRT seem to be better tolerated than sequences with everolimus or chemotherapy
Nutrition and neuroendocrine tumors: An update of the literature.
Neuroendocrine tumors (NETs) are a heterogeneous group of neoplasms with worldwide increasing incidence, high prevalence and survival. Both the tumor itself and the systemic therapy may have an impact on patients' nutrition. Malnutrition negatively impacts on outcome in NETs patients. Moreover, it has been demonstrated that body mass index was a risk factor for NET development and that metabolic syndrome was associated with worse prognosis in these patients. Of note, food could also interact with the metabolism of oral target therapy and antineoplastic agents used for the treatment of progressive NETs. Therefore, the nutritional assessment, based on body composition, and lifestyle modifications should be an integral component of management of the NET patients. The nutrition care plans are an integral part of the multidisciplinary management team for patients with NETs. Nutritionists with expertise in NETs can provide dietary approaches to improve the quality of life and nutritional status during various therapeutic modalities used in patients with NETs. The aim of this review is to critically discuss the importance of nutrition and body composition in patients with NETs
Droplet minimizers for the Gates-Lebowitz-Penrose free energy functional
We study the structure of the constrained minimizers of the
Gates-Lebowitz-Penrose free-energy functional ,
non-local functional of a density field , , a
-dimensional torus of side length . At low temperatures, is not convex, and has two distinct global minimizers,
corresponding to two equilibrium states. Here we constrain the average density
L^{-d}\int_{{\cal T}_L}m(x)\dd x to be a fixed value between the
densities in the two equilibrium states, but close to the low density
equilibrium value. In this case, a "droplet" of the high density phase may or
may not form in a background of the low density phase, depending on the values
and . We determine the critical density for droplet formation, and the
nature of the droplet, as a function of and . The relation between the
free energy and the large deviations functional for a particle model with
long-range Kac potentials, proven in some cases, and expected to be true in
general, then provides information on the structure of typical microscopic
configurations of the Gibbs measure when the range of the Kac potential is
large enough
- …
