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1.
Otol Neurotol ; 45(9): e618-e623, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-39264917

ABSTRACT

OBJECTIVE: To analyze the correlation between outcomes of stapes surgery and preoperative and postoperative audiometric results with different radiological staging classifications such as the Veillon classification (VC) and the Symons-Fanning classification (SFC). STUDY DESIGN: Retrospective observational study. SETTING: One tertiary hospital center. PATIENTS: Adult patients submitted to stapes surgery due to otosclerosis from January 2017 to December 2022. INTERVENTION: Evaluation of different radiological classifications such as the VC and SFC. MAIN OUTCOME MEASURES: Preoperative and postoperative pure-tone audiometric data, outcomes of stapes surgery success (closure of the ABG, rates of AC threshold less than or equal to 30 dB), and postoperative sensorineural hearing loss. RESULTS: A total of 87 patients and 97 operated ears were included. The SFC was associated with preoperative BC (p = 0.041) and AC (p = 0.018) and postoperative BC (p = 0.026) with an increase in thresholds with higher radiological stages. The VC was associated with postoperative AC (p = 0.045) with an increase in AC thresholds with increasing radiological stages. Lastly, both the VC (p = 0.032) and the SFC (p = 0.023) were associated with a decrease in rates of postoperative AC thresholds ≤30 dB with higher radiological stages. CONCLUSIONS: The SFC seems to be more useful to predict preoperative AC and BC and postoperative BC. On the contrary, the VC was more useful to predict postoperative AC. Both scales were similarly associated with the rate of AC thresholds ≤30 dB.


Subject(s)
Audiometry, Pure-Tone , Otosclerosis , Stapes Surgery , Humans , Otosclerosis/surgery , Otosclerosis/diagnostic imaging , Male , Female , Retrospective Studies , Middle Aged , Adult , Stapes Surgery/methods , Treatment Outcome , Tomography, X-Ray Computed , Aged , Hearing Loss, Sensorineural/diagnostic imaging , Hearing Loss, Sensorineural/surgery
2.
J Voice ; 2023 Dec 27.
Article in English | MEDLINE | ID: mdl-38155056

ABSTRACT

OBJECTIVE: The main objective of this study was to compare the demographic and clinical characteristics of patients with laryngeal dystonia (LD), dystonic tremor (DT), and vocal tremor (VT). STUDY DESIGN: This was a retrospective longitudinal study. METHODS: Data analysis from every patient diagnosed with LD, DT, or VT from January 1, 2010, to September 30, 2022, at a tertiary hospital center. Differential diagnosis between these entities was clinical (clinical history, voice assessment, and endoscopy) and confirmed by laryngeal electromyography. RESULTS: A total of 87 patients were included in this study: 50 patients with LD, 23 with DT, and 14 with VT. Age at diagnosis was significantly lower in patients with LD, with a mean age of 56.2 years when compared to DT (67.6 years; P = 0.002) and VT (70.5 years; P = 0.009). Furthermore, VT had a higher female prevalence (92.9%) when compared with LD (52%; P = 0.011). LD was mainly adductor, with only two patients diagnosed with abductor LD, and DT was adductor in every case. Tremor direction in patients with VT was horizontal in 50% and mixed (horizontal + vertical) in 50%, while in DT was mixed in 65.2% and horizontal in 34.8%. LD was more commonly an isolated laryngeal movement disorder (78%) when compared to DT (47.8%; P = 0.015) or VT (28.5%; P < 0.001), which were more often secondary to generalized neurological disorders. There were no differences between groups on Voice Handicap Index-10, self-reported grade of dysphonia on a visual analogic scale (0-10), maximum phonation time, and G, R, B, A, and I in the GRBAS-I scale at diagnosis (P > 0.05). S was significantly higher in LD when compared to VT (P < 0.001) and nonsignificantly higher than in DT (P = 0.075). CONCLUSIONS: LD, DT, and VT seem to be different entities with different demographics and clinical characteristics.

3.
Int Arch Otorhinolaryngol ; 27(4): e571-e578, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37876699

ABSTRACT

Introduction Clinical and pathological staging plays an important role on the prognosis of head and neck cancer (HNC) patients. Objective The present study aims to compare clinical and pathological T, N and overall staging in patients with HNC, to identify factors associated with these discrepancies, and to analyze and compare survival or disease-free survival in staging disagreements. Methods Retrospective cohort including every patient submitted to neck dissection from January 2010 to December 2020 in the department of Otorhinolaryngology of a tertiary hospital center. Results A total of 79 patients were analyzed; their mean age was 58.52 ± 13.15 years old and 88.9% were male. Assessing overall staging, discrepancies were noted in 53% (36.4% upstaging and 16.6% downstaging) and were significantly associated with clinical overall staging ( p = 0.006). Regarding T staging, differences were noted in 45.5% (30.3% upstaging and 15.2% downstaging) and were significantly associated with imaging modality ( p = 0.016), clinical T staging ( p = 0.049), and histology ( p = 0.017). Discrepancies in N staging were noted in 38% (25.3% upstaging and 12.7% downstaging) and were significantly associated with age ( p = 0.013), clinical N staging ( p < 0.001), and presence of extranodal invasion ( p < 0.001). Both in Overall, T, and N staging, the aforementioned disagreements were not associated with either higher mortality or higher disease relapse. Conclusion Overall, T, and N staging disagree in an important number of cases, and the overall stage can disagree in up to 53% of the cases. These disagreements do not seem to influence overall and disease-free survival.

4.
Int. arch. otorhinolaryngol. (Impr.) ; 27(4): 571-578, 2023. tab
Article in English | LILACS-Express | LILACS | ID: biblio-1528728

ABSTRACT

Abstract Introduction Clinical and pathological staging plays an important role on the prognosis of head and neck cancer (HNC) patients. Objective The present study aims to compare clinical and pathological T, N and overall staging in patients with HNC, to identify factors associated with these discrepancies, and to analyze and compare survival or disease-free survival in staging disagreements. Methods Retrospective cohort including every patient submitted to neck dissection from January 2010 to December 2020 in the department of Otorhinolaryngology of a tertiary hospital center. Results A total of 79 patients were analyzed; their mean age was 58.52 ± 13.15 years old and 88.9% were male. Assessing overall staging, discrepancies were noted in 53% (36.4% upstaging and 16.6% downstaging) and were significantly associated with clinical overall staging (p = 0.006). Regarding T staging, differences were noted in 45.5% (30.3% upstaging and 15.2% downstaging) and were significantly associated with imaging modality (p = 0.016), clinical T staging (p = 0.049), and histology (p = 0.017). Discrepancies in N staging were noted in 38% (25.3% upstaging and 12.7% downstaging) and were significantly associated with age (p = 0.013), clinical N staging (p < 0.001), and presence of extranodal invasion (p < 0.001). Both in Overall, T, and N staging, the aforementioned disagreements were not associated with either higher mortality or higher disease relapse. Conclusion Overall, T, and N staging disagree in an important number of cases, and the overall stage can disagree in up to 53% of the cases. These disagreements do not seem to influence overall and disease-free survival.

5.
Sensors (Basel) ; 21(21)2021 Nov 01.
Article in English | MEDLINE | ID: mdl-34770592

ABSTRACT

Non-standard diesel blends can be harmful to the environment and human health. In this context, a simple analytical method to estimate the biodiesel mixture ratio in diesel was developed based on impedance spectroscopy (IS) associated with interdigitated sensors. In this article, four different interdigitated sensors with varied comb spacing (G) were simulated using the COMSOL Multiphysics software. Based on finite element simulations, four interdigitated electrode architectures were manufactured and evaluated. The best geometry was chosen according to theoretical data simulations, and its interdigitated electrodes were manufactured for the compositional evaluation of pseudo-binary biodiesel-diesel mixtures. According to the X-ray powder diffraction technique, the deposition of the conductive layer (Au0) over the surface of the dielectric substrate (SiO2) did not alter its phase composition. In the analysis of AFM and SEM, it was possible to observe irregular edges on the electrodes, possibly related to the manufacturing process of the thin layers and mechanical stability. Another characteristic observed in the AFM images was the height of the step of the gold layer of the sensor. Several cross sections were obtained, and the mean step value was 225.71 ± 0.0032 nm. Although there were differences in the roughness, the whole sensor had nanometric roughness. Based on the finite element method simulation performed, it can be assumed that the geometric parameters more suitable for the manufacturing of the electrode are W = 20 µm, L = 1000 µm, G = 50 µm, and N = 40 digits. The electrical characterization performed by impedance spectroscopy showed that we could differentiate between biodiesel and diesel fuels and their pseudo-binary mixtures in the low-frequency region.


Subject(s)
Biofuels , Silicon Dioxide , Electrodes , Gasoline , Gold , Humans
6.
Sensors (Basel) ; 21(18)2021 Sep 16.
Article in English | MEDLINE | ID: mdl-34577405

ABSTRACT

In this paper, a bioinspired method in the magnetic field memory of the bees, applied in a rover of precision pollination, is presented. The method calculates sharpness features by entropy and variance of the Laplacian of images segmented by color in the HSV system in real-time. A complementary positioning method based on area feature extraction between active markers was developed, analyzing color characteristics, noise, and vibrations of the probe in time and frequency, through the lateral image of the probe. From the observed results, it can be seen that the unsupervised method does not require previous calibration of target dimensions, histogram, and distances involved in positioning. The algorithm showed less sensitivity in the extraction of sharpness characteristics regarding the number of edges and greater sensitivity to the gradient, allowing unforeseen operation scenarios, even in small sharpness variations, and robust response to variance local, temporal, and geophysical of the magnetic declination, not needing luminosity after scanning, with the two freedom of degrees of the rotation.


Subject(s)
Algorithms , Pollination , Animals , Bees , Calibration , Entropy , Magnetic Fields
7.
Preprint in English | medRxiv | ID: ppmedrxiv-21260849

ABSTRACT

BackgroundHemodialyzed patients are at higher risk for COVID-19 and were prioritized in the Portuguese vaccination campaign MethodsWe performed a prospective, longitudinal, cohort analysis of 143 patients on hemodialysis and 143 age-matched controls along BTN162b2 vaccination. ELISA quantified anti-full-length Spike IgG, IgM and IgA levels prior to the first vaccine dose (t0); 3 weeks later (second dose, t1); and 3 weeks later (t2); 127 patients were re-evaluated140 (t3) and 180 days (t4) after the first dose. ResultsSeroconversion at t1 was remarkably low in patients, with positivity for anti-spike IgG, IgM and IgA antibodies of 29.4%, 12% and 41%, respectively, increasing to 90.9% (IgG) and 83.9% (IgA) in t2, (IgM remained unchanged). Below 70 years of age anti-spike IgG levels at t1 were significantly lower compared to age-matched controls and showed a profile similar to older individuals. Immunosuppression was associated with lower antibody responses (p=0.005 at t1; p=0.008 at t2). Previous unresponsiveness to hepatitis B vaccination (75/129, 58% of patients negative for anti-HBs antibodies) did not correlate with humoral unresponsiveness to BTN162b2. Anti-spike IgG, IgM and IgA positivity and antibody levels significantly decay at t3, with IgG levels showing further waning at t4. ConclusionsThe large majority of hemodialyzed patients showed IgG seroconversion upon BNT162b2 mRNA vaccination, albeit a sizable proportion of patients presented poor responses. Follow-up of antibody responses 180 days post vaccination unveiled significant decay of anti-spike antibodies and warrant close monitoring of COVID-19 infection and further studies on reinforced vaccination schedules in patients undergoing maintenance hemodialysis.

8.
Preprint in English | medRxiv | ID: ppmedrxiv-21254188

ABSTRACT

There is a consensus that mass vaccination against SARS-CoV-2 will ultimately end the COVID-19 pandemic. However, it is not clear when and which control measures can be relaxed during the rollout of vaccination programmes. We investigate relaxation scenarios using an age-structured transmission model that has been fitted to age-specific seroprevalence data, hospital admissions, and projected vaccination coverage for Portugal. Our analyses suggest that the pressing need to restart socioeconomic activities could lead to new pandemic waves, and that substantial control efforts prove necessary throughout 2021. Using knowledge on control measures introduced in 2020, we anticipate that relaxing measures completely or to the extent as in autumn 2020 could launch a wave starting in April 2021. Additional waves could be prevented altogether if measures are relaxed as in summer 2020 or in a step-wise manner throughout 2021. We discuss at which point control of COVID-19 would be achieved for each scenario.

9.
Sci Rep ; 10(1): 19938, 2020 11 17.
Article in English | MEDLINE | ID: mdl-33203915

ABSTRACT

The recent findings of increased Choroidal Thickness (CT) in Keratoconus (KC) patients raised the question of whether CT could be an indicator of progressive KC. To test this hypothesis, we evaluated and compared the choroidal profile in progressive and non-progressive KC. We ran a cross-sectional observational study in 76 patients diagnosed with KC, age 14-30, to assess KC progression. Progression was defined as when at least two of the studied variables confirmed progression (Kmax, Km, PachyMin, D-Index, Astig, K2, 3 mm PCR). Included patients performed a Spectralis Optical Coherence Tomography (OCT) with enhanced depth image (EDI) technology to evaluate choroidal profile. Choroidal measurements were taken subfoveally and at 500 µm intervals from the fovea, in 7 different locations, and compared between groups. Multivariate linear regression analyses were also performed to assess the influence of CT in KC progression. Thirty-six eyes (47.4%) were classified as KC progressors. The mean subfoveal CT observed in the total sample was 382.0 (± 97.0) µm. The comparison between groups (progressive and non-progressive KC) showed no differences in the locations evaluated (mean subfoveal CT difference between groups was 2.4 µm, p = 0.915). In the multivariate analysis CT seems not be influenced by KC progression (B = 6.72 µm, 95% CI - 40.09 to 53.53, p = 0.775). Assessment of choroidal profile does not appear to be a useful tool to differentiate progressive and non-progressive KC. Further research is needed in order to better understand the role of choroid in KC.


Subject(s)
Choroid/pathology , Keratoconus/pathology , Tomography, Optical Coherence/methods , Visual Acuity , Adolescent , Adult , Choroid/diagnostic imaging , Cross-Sectional Studies , Disease Progression , Female , Humans , Image Enhancement , Keratoconus/diagnostic imaging , Male , Young Adult
10.
ISA Trans ; 90: 294-310, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30732992

ABSTRACT

In this paper, a novel approach for online design of optimal control systems applied to the bulk resumption process by bucket wheel reclaimer (BWR) is presented. This approach is based on reinforcement learning paradigms, more specifically Action Dependent Heuristic Dynamic Programming (ADHDP), that learn online in real-time the Discrete Linear Quadratic Regulator (DLQR) optimal control solution with integral action. Due to the geometric irregularities of the storage yard stacks and variation in physical and chemical characteristics of the stacked material, the flow control of solid bulks by bucket wheel reclaimer requires methods that are suitable with the high degree of imprecision of process variables and environment uncertainties. The resumption of bulk solids is carried out by dividing the stack into layers, each layer is approximately 4 m high, and the layers are divided into workbenches up to 12 m in length. To take up a workbench several translation steps are required (penetration in the stack), with the translation step varying from 0 to 1 m. In order to maintain the desired ore flow throughout the process, the BWR lance speed must be periodically adjusted. The main advantage of the proposed control method is that besides the decision rule is fully independent of plant model, the gains of the resulting controller are self-adjustable. The control system was designed in such a way that the ADHDP-based DLQR controller with integral action would act in real-time in the plant control, using only the input and output signals and states measured along the system trajectory.

11.
Chaos ; 22(2): 026114, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22757573

ABSTRACT

We investigate the effect of white-noise perturbations on chaotic trajectories in open billiards. We focus on the temporal decay of the survival probability for generic mixed-phase-space billiards. The survival probability has a total of five different decay regimes that prevail for different intermediate times. We combine new calculations and recent results on noise perturbed Hamiltonian systems to characterize the origin of these regimes and to compute how the parameters scale with noise intensity and billiard openness. Numerical simulations in the annular billiard support and illustrate our results.

12.
IEEE Trans Syst Man Cybern B Cybern ; 40(2): 266-85, 2010 Apr.
Article in English | MEDLINE | ID: mdl-19661008

ABSTRACT

Toward the synthesis of state-space controllers, a neural-genetic model based on the linear quadratic regulator design for the eigenstructure assignment of multivariable dynamic systems is presented. The neural-genetic model represents a fusion of a genetic algorithm and a recurrent neural network (RNN) to perform the selection of the weighting matrices and the algebraic Riccati equation solution, respectively. A fourth-order electric circuit model is used to evaluate the convergence of the computational intelligence paradigms and the control design method performance. The genetic search convergence evaluation is performed in terms of the fitness function statistics and the RNN convergence, which is evaluated by landscapes of the energy and norm, as a function of the parameter deviations. The control problem solution is evaluated in the time and frequency domains by the impulse response, singular values, and modal analysis.

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