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1.
BMC Womens Health ; 24(1): 38, 2024 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-38218823

RESUMO

BACKGROUND: Immune checkpoint inhibitors (ICIs) can improve survivals of metastatic triple negative breast cancer (mTNBC); however, we still seek circulating blood biomarkers to predict the efficacy of ICIs. MATERIALS AND METHODS: In this study, we analyzed the data of ICIs treated mTNBC collected in Anhui Medical University affiliated hospitals from 2018 to 2023. The counts of lymphocytes, monocytes, platelets, and ratio indexes (NLR, MLR, PLR) in peripheral blood were investigated via the Kaplan-Meier curves and the Cox proportional-hazards model. RESULTS: The total of 50 mTNBC patients were treated with ICIs. High level of peripheral lymphocytes and low level of NLR and MLR at baseline and post the first cycle of ICIs play the predictable role of immunotherapies. Lymphocytes counts (HR = 0.280; 95% CI: 0.095-0.823; p = 0.021) and NLR (HR = 1.150; 95% CI: 1.052-1.257; p = 0.002) are significantly correlated with overall survival. High NLR also increases the risk of disease progression (HR = 2.189; 95% CI:1.085-4.414; p = 0.029). When NLR at baseline ≥ 2.75, the hazard of death (HR = 2.575; 95% CI:1.217-5.447; p = 0.013) and disease progression (HR = 2.189; 95% CI: 1.085-4.414; p = 0.029) significantly rise. HER-2 expression and anti-tumor therapy lines are statistically correlated with survivals. CONCLUSIONS: Before the initiation of ICIs, enriched peripheral lymphocytes and poor neutrophils and NLR contribute to the prediction of survivals.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Prognóstico , Biomarcadores , Linfócitos/patologia , Progressão da Doença , Estudos Retrospectivos , Biomarcadores Tumorais
2.
Crit Care Med ; 51(12): 1638-1649, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37651262

RESUMO

OBJECTIVES: To assess the value of machine learning approaches in the development of a multivariable model for early prediction of ICU death in patients with acute respiratory distress syndrome (ARDS). DESIGN: A development, testing, and external validation study using clinical data from four prospective, multicenter, observational cohorts. SETTING: A network of multidisciplinary ICUs. PATIENTS: A total of 1,303 patients with moderate-to-severe ARDS managed with lung-protective ventilation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We developed and tested prediction models in 1,000 ARDS patients. We performed logistic regression analysis following variable selection by a genetic algorithm, random forest and extreme gradient boosting machine learning techniques. Potential predictors included demographics, comorbidities, ventilatory and oxygenation descriptors, and extrapulmonary organ failures. Risk modeling identified some major prognostic factors for ICU mortality, including age, cancer, immunosuppression, Pa o2 /F io2 , inspiratory plateau pressure, and number of extrapulmonary organ failures. Together, these characteristics contained most of the prognostic information in the first 24 hours to predict ICU mortality. Performance with machine learning methods was similar to logistic regression (area under the receiver operating characteristic curve [AUC], 0.87; 95% CI, 0.82-0.91). External validation in an independent cohort of 303 ARDS patients confirmed that the performance of the model was similar to a logistic regression model (AUC, 0.91; 95% CI, 0.87-0.94). CONCLUSIONS: Both machine learning and traditional methods lead to promising models to predict ICU death in moderate/severe ARDS patients. More research is needed to identify markers for severity beyond clinical determinants, such as demographics, comorbidities, lung mechanics, oxygenation, and extrapulmonary organ failure to guide patient management.


Assuntos
Síndrome do Desconforto Respiratório , Humanos , Unidades de Terapia Intensiva , Pulmão , Estudos Prospectivos , Respiração Artificial/métodos , Síndrome do Desconforto Respiratório/terapia
3.
Clin Transl Oncol ; 25(3): 796-802, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36418642

RESUMO

BACKGROUND: There is a lack of knowledge about the career paths and employment situation of young medical oncologists. The aim of our study was to evaluate the current professional standing of these professionals in Spain. METHODS: The Spanish Society of Medical Oncology + MIR section conducted a national online survey in May 2021 of young medical oncology consultants (< 6 years of expertise) and final year medical oncology residents. RESULTS: A total of 162 responses were eligible for analysis and included participants from 16 autonomous communities; 64% were women, 80% were consultants, and 20% were residents. More than half of the participants performed routine healthcare activity and only 7% research activity. Almost three quarters (73%) were subspecialized in a main area of interest and almost half of these chose this area because it was the only option available after residency. Half of the respondents (51%) considered working abroad and 81% believed the professional standing in Spain was worse than in other countries. After finishing their residency, only 22 were offered a job at their training hospital. Just 16% of participants had a permanent employment contract and 87% were concerned (score of ≥ 5 on a scale of 1-10) about their job stability. In addition, one quarter of the participants in our study showed an interest in increasing their research activity. CONCLUSIONS: The choice of subspecialty in medical oncology may depend on job opportunities after residency rather than personal interest. The abundance of temporary contracts may have influenced the job stability concerns observed. Future mentoring strategies should engage in building a long-term career path for young medical oncologists.


Assuntos
Oncologia , Oncologistas , Humanos , Feminino , Masculino , Espanha , Inquéritos e Questionários , Emprego
4.
Front Psychol ; 13: 963666, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36483712

RESUMO

An ironic statement transmits the opposite meaning to its literal counterpart and is one of the most complex communicative acts. Thus, it has been proposed to be a good indicator of social communication ability. Prosody and facial expression are two crucial paralinguistic cues that can facilitate the understanding of ironic statements. The primary aim of this study was to create and evaluate a task of irony identification that could be used in neuroimaging studies. We independently evaluated three cues, contextual discrepancy, prosody and facial expression, and selected the best cue that would lead participants in fMRI studies to identify a stimulus as ironic in a reliable way. This process included the design, selection, and comparison of the three cues, all of which have been previously associated with irony detection. The secondary aim was to correlate irony comprehension with specific cognitive functions. Results showed that psycholinguistic properties could differentiate irony from other communicative acts. The contextual discrepancy, prosody, and facial expression were relevant cues that helped detect ironic statements; with contextual discrepancy being the cue that produced the highest classification accuracy and classification time. This task can be used successfully to test irony comprehension in Spanish speakers using the cue of interest. The correlation of irony comprehension with cognitive functions did not yield consistent results. A more heterogeneous sample of participants and a broader battery of tests may be needed to find reliable cognitive correlates of irony comprehension.

5.
Micromachines (Basel) ; 13(11)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36363950

RESUMO

A full comprehension of colorimetric relationships within and between teeth is key for aesthetic success of a dental restoration. In this sense, hyperspectral imaging can provide point-wise reliable measurements of the tooth surface, which can serve for this purpose. The aim of this study was to use a hyperspectral imaging system for the colorimetric characterization of 4 in-vivo maxillary anterior teeth and to cross-check the results with similar studies carried out with other measuring systems in order to validate the proposed capturing protocol. Hyperspectral reflectance images (Specim IQ), of the upper central (UCI) and lateral incisors (ULI), were captured on 30 participants. CIE-L*a*b* values were calculated for the incisal (I), middle (M) and cervical (C) third of each target tooth. ΔEab* and ΔE00 total color differences were computed between different tooth areas and adjacent teeth, and evaluated according to the perceptibility (PT) and acceptability (AT) thresholds for dentistry. Non-perceptible color differences were found between UCIs and ULIs. Mean color differences between UCI and ULI exceeded AT (ΔEab* = 7.39-7.42; ΔE00 = 5.71-5.74) in all cases. Large chromatic variations between I, M and C areas of the same tooth were registered (ΔEab* = 5.01-6.07 and ΔE00 = 4.07-5.03; ΔEab* = 5.80-8.16 and ΔE00 = 4.37-5.15; and ΔEab* = 5.42-5.92 and ΔE00 = 3.87-4.16 between C and M, C and I and M and I, respectively). The use of a hyperspectral camera has proven to be a reliable and effective method for color evaluation of in-vivo natural teeth.

6.
Opt Express ; 30(11): 19757-19770, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-36221743

RESUMO

The use of blue-blocking filters is increasing in spectacle lens users. Despite the low absorption in the blue range, some users complain about these filters because they affect their color perception. In a pilot study we have evaluated how the long-term use of 8 different blue-blocking filters impact the color perception during more than 2 weeks on a group of 18 normal color vision observers, compared with a control group of 10 observers. The evaluation was done using the FM100, the Color Assessment and Diagnosis (CAD) and an achromatic point measurement. Our results show that there is a trend to worsen with the filters on.


Assuntos
Percepção de Cores , Óculos , Cor , Projetos Piloto
7.
Opt Express ; 30(19): 34665-34683, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36242474

RESUMO

Color vision deficiency (CVD) has gained in relevance in the last decade, with a surge of proposals for aid systems that aim to improve the color discrimination capabilities of CVD subjects. This paper focuses on the proposal of a new metric called CVD-MET, that can evaluate the efficiency and naturalness of these systems through a set of images using a simulation of the subject's vision. In the simulation, the effect of chromatic adaptation is introduced via CIECAM02, which is relevant for the evaluation of passive aids (color filters). To demonstrate the potential of the CVD-MET, an evaluation of a representative set of passive and active aids is carried out both with conventional image quality metrics and with CVD-MET. The results suggest that the active aids (recoloration algorithms) are in general more efficient and produce more natural images, although the changes that are introduced do not shift the CVD's perception of the scene towards the normal observer's perception.


Assuntos
Doenças Cardiovasculares , Defeitos da Visão Cromática , Visão de Cores , Algoritmos , Cor , Percepção de Cores , Defeitos da Visão Cromática/diagnóstico , Simulação por Computador , Humanos , Visão Ocular
8.
BMC Health Serv Res ; 22(1): 948, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35883128

RESUMO

OBJECTIVE: Analyze the cost contributors and their impact on the drug cost avoidance (DCA) resulting from cancer clinical trials over the period of 2015-2020 in a tertiary-level hospital in Spain (HCUVA). METHODS: We performed a cross-sectional, observational, retrospective study of a total of 53 clinical trials with 363 patients enrolled. We calculated the DCA from the price of the best standard of care (i.e.: drugs that the institution would otherwise fund). A linear regression model was used to determine cost contributors and estimate their impact. RESULTS: The total DCA was ~ 4.9 million euros (31 clinical trials; 177 enrollees), representing ~ 30% and ~ 0,05% approximately of the annual pharmaceutical expenditures at the HCUVA and for the Spanish Health System, respectively. Cancer type analysis showed that lung cancer had the highest average DCA by trial, indicating that treatments in these trials were the most expensive. Linear regression analysis showed that the number of patients in a trial did not significantly affect that trial's DCA. Instead, cancer type, phase trials, and intention of treatment were significant cost contributors to DCA. Compared to digestive cancer trials, breast and lung trials were significantly more expensive, (p < 0.05 and p < 0.1, respectively). Phase III trials were more expensive than Phase II (p < 0.01) and adjuvant trials were less expensive than palliative (p < 0.05). CONCLUSION: We studied cost contributors that significantly impacted the estimated DCA from cancer clinical trials. Our work provides the groundwork to explore DCA contributors with potential to enhance public relations material and serve as a negotiating tool for budgeting, thus playing an important role to inform decisions about resource allocation.


Assuntos
Custos de Medicamentos , Neoplasias Pulmonares , Estudos Transversais , Humanos , Estudos Retrospectivos , Espanha
9.
Crit Care Explor ; 4(5): e0684, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35510152

RESUMO

OBJECTIVES: To establish the epidemiological characteristics, ventilator management, and outcomes in patients with acute hypoxemic respiratory failure (AHRF), with or without acute respiratory distress syndrome (ARDS), in the era of lung-protective mechanical ventilation (MV). DESIGN: A 6-month prospective, epidemiological, observational study. SETTING: A network of 22 multidisciplinary ICUs in Spain. PATIENTS: Consecutive mechanically ventilated patients with AHRF (defined as Pao2/Fio2 ≤ 300 mm Hg on positive end-expiratory pressure [PEEP] ≥ 5 cm H2O and Fio2 ≥ 0.3) and followed-up until hospital discharge. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Primary outcomes were prevalence of AHRF and ICU mortality. Secondary outcomes included prevalence of ARDS, ventilatory management, and use of adjunctive therapies. During the study period, 9,803 patients were admitted: 4,456 (45.5%) received MV, 1,271 (13%) met AHRF criteria (1,241 were included into the study: 333 [26.8%] met Berlin ARDS criteria and 908 [73.2%] did not). At baseline, tidal volume was 6.9 ± 1.1 mL/kg predicted body weight, PEEP 8.4 ± 3.1 cm H2O, Fio2 0.63 ± 0.22, and plateau pressure 21.5 ± 5.4 cm H2O. ARDS patients received higher Fio2 and PEEP than non-ARDS (0.75 ± 0.22 vs 0.59 ± 0.20 cm H2O and 10.3 ± 3.4 vs 7.7 ± 2.6 cm H2O, respectively [p < 0.0001]). Adjunctive therapies were rarely used in non-ARDS patients. Patients without ARDS had higher ventilator-free days than ARDS (12.2 ± 11.6 vs 9.3 ± 9.7 d; p < 0.001). All-cause ICU mortality was similar in AHRF with or without ARDS (34.8% [95% CI, 29.7-40.2] vs 35.5% [95% CI, 32.3-38.7]; p = 0.837). CONCLUSIONS: AHRF without ARDS is a very common syndrome in the ICU with a high mortality that requires specific studies into its epidemiology and ventilatory management. We found that the prevalence of ARDS was much lower than reported in recent observational studies.

10.
Opt Express ; 30(8): 13699-13713, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35472977

RESUMO

There is a belief that observers with color vision deficiencies (CVD) perform better in detecting camouflaged objects than normal observers. Some studies have concluded contradictory findings when studying the performance of normal and CVD observers in the camouflage detection tasks in different conditions. This work presents a literature review on this topic, dividing it into three different and contradictory types of results: better performance for CVD, for normal observers, or same performance. Besides, two psychophysical experiments have been designed and carried out in a calibrated computer monitor on both normal and CVD human observers to measure the searching times of the different types of observers needed to find camouflaged stimuli in two different types of stimuli. Results show the trend that, in our experimental conditions, normal observers need shorter searching times than CVD observers in finding camouflaged stimuli both in images of natural scenes and in images with synthetic stimuli.


Assuntos
Doenças Cardiovasculares , Defeitos da Visão Cromática , Defeitos da Visão Cromática/diagnóstico , Humanos
11.
Sensors (Basel) ; 21(17)2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34502824

RESUMO

Images captured under bad weather conditions (e.g., fog, haze, mist, dust, etc.), suffer from poor contrast and visibility, and color distortions. The severity of this degradation depends on the distance, the density of the atmospheric particles and the wavelength. We analyzed eight single image dehazing algorithms representative of different strategies and originally developed for RGB images, over a database of hazy spectral images in the visible range. We carried out a brute force search to find the optimum three wavelengths according to a new combined image quality metric. The optimal triplet of monochromatic bands depends on the dehazing algorithm used and, in most cases, the different bands are quite close to each other. According to our proposed combined metric, the best method is the artificial multiple exposure image fusion (AMEF). If all wavelengths within the range 450-720 nm are used to build a sRGB renderization of the imagaes, the two best-performing methods are AMEF and the contrast limited adaptive histogram equalization (CLAHE), with very similar quality of the dehazed images. Our results show that the performance of the algorithms critically depends on the signal balance and the information present in the three channels of the input image. The capture time can be considerably shortened, and the capture device simplified by using a triplet of bands instead of the full wavelength range for dehazing purposes, although the selection of the bands must be performed specifically for a given algorithm.

12.
Crit Care Med ; 49(10): e920-e930, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34259448

RESUMO

OBJECTIVES: To develop a scoring model for stratifying patients with acute respiratory distress syndrome into risk categories (Stratification for identification of Prognostic categories In the acute RESpiratory distress syndrome score) for early prediction of death in the ICU, independent of the underlying disease and cause of death. DESIGN: A development and validation study using clinical data from four prospective, multicenter, observational cohorts. SETTING: A network of multidisciplinary ICUs. PATIENTS: One-thousand three-hundred one patients with moderate-to-severe acute respiratory distress syndrome managed with lung-protective ventilation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The study followed Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis guidelines for prediction models. We performed logistic regression analysis, bootstrapping, and internal-external validation of prediction models with variables collected within 24 hours of acute respiratory distress syndrome diagnosis in 1,000 patients for model development. Primary outcome was ICU death. The Stratification for identification of Prognostic categories In the acute RESpiratory distress syndrome score was based on patient's age, number of extrapulmonary organ failures, values of end-inspiratory plateau pressure, and ratio of Pao2 to Fio2 assessed at 24 hours of acute respiratory distress syndrome diagnosis. The pooled area under the receiver operating characteristic curve across internal-external validations was 0.860 (95% CI, 0.831-0.890). External validation in a new cohort of 301 acute respiratory distress syndrome patients confirmed the accuracy and robustness of the scoring model (area under the receiver operating characteristic curve = 0.870; 95% CI, 0.829-0.911). The Stratification for identification of Prognostic categories In the acute RESpiratory distress syndrome score stratified patients in three distinct prognostic classes and achieved better prediction of ICU death than ratio of Pao2 to Fio2 at acute respiratory distress syndrome onset or at 24 hours, Acute Physiology and Chronic Health Evaluation II score, or Sequential Organ Failure Assessment scale. CONCLUSIONS: The Stratification for identification of Prognostic categories In the acute RESpiratory distress syndrome score represents a novel strategy for early stratification of acute respiratory distress syndrome patients into prognostic categories and for selecting patients for therapeutic trials.


Assuntos
Síndrome do Desconforto Respiratório/classificação , APACHE , Adulto , Área Sob a Curva , Feminino , Humanos , Unidades de Terapia Intensiva/organização & administração , Unidades de Terapia Intensiva/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Escores de Disfunção Orgânica , Prognóstico , Estudos Prospectivos , Curva ROC , Respiração Artificial/normas , Respiração Artificial/estatística & dados numéricos , Síndrome do Desconforto Respiratório/complicações , Síndrome do Desconforto Respiratório/mortalidade , Índice de Gravidade de Doença , Espanha/epidemiologia
13.
Antioxidants (Basel) ; 10(4)2021 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-33916531

RESUMO

(1) Background: Prunus species have the ability to suspend (induce dormancy) and restart growth, in an intricate process in which environmental and physiological factors interact. (2) Methods: In this work, we studied the evolution of sugars, antioxidant metabolism, and abscisic acid (ABA) and gibberellins (GAs) levels during bud dormancy evolution in a high-chill peach variety, grown for two seasons in two different geographical areas with different annual media temperature, a cold (CA) and a temperate area (TA). (3) Results: In both areas, starch content reached a peak at ecodormancy, and then decreased at dormancy release (DR). Sorbitol and sucrose declined at DR, mainly in the CA. In contrast, glucose and fructose levels progressively rose until DR. A decline in ascorbate peroxidase, dehydroascorbate reductase, superoxide dismutase and catalase activities occurred in both seasons at DR. Moreover, the H2O2-sensitive SOD isoenzymes, Fe-SOD and Cu,Zn-SOD, and two novel peroxidase isoenzymes, were detected. Overall, these results suggest the occurrence of a controlled oxidative stress during DR. GA7 was the major bioactive GA in both areas, the evolution of its levels being different between seasons and areas. In contrast, ABA content decreased during the dormancy period in both areas, resulting in a reduction in the ABA/total GAs ratio, being more evident in the CA. (4) Conclusion: A possible interaction sugars-hormones-ROS could take place in high-chill peach buds, favoring the DR process, suggesting that, in addition to sugar metabolism, redox interactions can govern bud DR, regardless of chilling requirements.

14.
Future Oncol ; 17(12): 1545-1551, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33626935

RESUMO

Purpose: The purpose of this study was to disclose the variability of pathways currently taken in the treatment of adolescent patients from diagnosis to final follow-up with a view to developing a more homogenous system. Patients & methods: A cross-sectional, observational and retrospective study of the cancer diagnosis and assignment to medical care teams in adolescent patients (12-20 years) from January 2008 to December 2018 was conducted. A total of 345 adolescent patients aged between 12 and 20 years, diagnosed with cancer and treated at Hospital Clinico Universitario Virgen de la Arrixaca were included. Results: CNS tumors, followed by leukemia were the most frequent tumors. At the time of diagnosis, the highest incidences of patients were assisted in the pediatrics service adult oncology service (21.7%) and hematology (11%). Conclusion: Our aim is to highlight the need for a better transition for patients from pediatric to adult oncology and hematology services.


Lay abstract This study shows the reality of the care of adolescent cancer patients in a hospital in southern Spain. A cross-sectional, observational and retrospective study of cancer diagnoses and assignment to medical care teams in adolescent patients (12­20 years) from January 2008 to December 2018 was conducted. A total of 345 adolescent patients between 12 and 20 years old who had a cancer diagnosis and were treated at Hospital Clinico Universitario Virgen de la Arrixaca were included. CNS tumors, followed by leukemia were the most frequent. At the time of diagnosis, the patients were most commonly attended by the pediatrics service, which concentrates 46.5% of the study population. There is great variability in the treatment and follow-up of the same tumors. The need for a better transition for patients from pediatric to adult oncology and hematology services is demonstrated.


Assuntos
Procedimentos Clínicos/organização & administração , Neoplasias/terapia , Equipe de Assistência ao Paciente/organização & administração , Melhoria de Qualidade , Transição para Assistência do Adulto/organização & administração , Adolescente , Assistência ao Convalescente/organização & administração , Assistência ao Convalescente/estatística & dados numéricos , Criança , Procedimentos Clínicos/estatística & dados numéricos , Estudos Transversais , Feminino , Humanos , Incidência , Masculino , Oncologia/organização & administração , Oncologia/estatística & dados numéricos , Neoplasias/diagnóstico , Neoplasias/epidemiologia , Pediatria/organização & administração , Pediatria/estatística & dados numéricos , Encaminhamento e Consulta/organização & administração , Encaminhamento e Consulta/estatística & dados numéricos , Estudos Retrospectivos , Centros de Atenção Terciária/organização & administração , Centros de Atenção Terciária/estatística & dados numéricos , Transição para Assistência do Adulto/estatística & dados numéricos , Adulto Jovem
15.
Sensors (Basel) ; 21(3)2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33535556

RESUMO

Saliency prediction is a very important and challenging task within the computer vision community. Many models exist that try to predict the salient regions on a scene from its RGB image values. Several new models are developed, and spectral imaging techniques may potentially overcome the limitations found when using RGB images. However, the experimental study of such models based on spectral images is difficult because of the lack of available data to work with. This article presents the first eight-channel multispectral image database of outdoor urban scenes together with their gaze data recorded using an eyetracker over several observers performing different visualization tasks. Besides, the information from this database is used to study whether the complexity of the images has an impact on the saliency maps retrieved from the observers. Results show that more complex images do not correlate with higher differences in the saliency maps obtained.

16.
Sensors (Basel) ; 20(24)2020 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-33322212

RESUMO

In the cultural heritage preservation of medieval buildings, it is common to find plaster walls covered in lime, which previously were painted in polychromy. The conservation interventions usually try to remove the whitewash, whilst maintaining the original color of the painted wall as much as possible. However, there is no agreement on which cleaning technique best preserves the original appearance of the colored plaster. Different pigments found below the lime layer may behave differently depending on the cleaning technique used. Usually, colorimetric or photometric area-based measurements are carried out to study the color of the cleaned areas to compare with their original color, obtained from pre-made plaster probes. However, this methodology fails when the mean color difference is not enough to fully characterize the changes in texture and color appearance. This study presents a set of experiments carried out using two different pigments (cinnabar and malachite) covered with lime, and treated with nine different cleaning techniques on plaster probes prepared according to medieval techniques. We have studied the effect of the cleaning process on the color and the homogeneity of the samples using a hyperspectral imaging workflow. Four different analysis methods are presented and discussed. Our results show that the proposed analysis is able to provide a much more comprehensive and diversified characterization of the quality of the cleaning method compared to the commonly used colorimetric or photometric area-based measurements.

17.
Sensors (Basel) ; 20(22)2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33238413

RESUMO

In foggy or hazy conditions, images are degraded due to the scattering and attenuation of atmospheric particles, reducing the contrast and visibility and changing the color. This degradation depends on the distance, the density of the atmospheric particles and the wavelength. We have tested and applied five single image dehazing algorithms, originally developed to work on RGB images and not requiring user interaction and/or prior knowledge about the images, on a spectral hazy image database in the visible range. We have made the evaluation using two strategies: the first is based on the analysis of eleven state-of-the-art metrics and the second is two psychophysical experiments with 126 subjects. Our results suggest that the higher the wavelength within the visible range is, the higher the quality of the dehazed images. The quality increases for low haze/fog levels. The choice of the best performing algorithm depends on the criterion prioritized by the metric design strategy. The psychophysical experiment results show that the level of agreement between observers and metrics depends on the criterion set for the observers' task.

18.
Opt Lett ; 45(18): 5117-5118, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32932489

RESUMO

Recently Karepov and Ellenbogen [Opt. Lett.45, 1379 (2020)OPLEDP0146-959210.1364/OL.384970] claimed that a new metasurface-based contact lens is able to correct deuteranomaly. Unfortunately, their results are not supported by psychophysical experiments, and some key assumptions in their simulations were misinterpreted. All of this has led to wrong conclusions providing false expectations to the color vision deficiency community.

19.
Intensive Care Med ; 46(12): 2327-2337, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32893313

RESUMO

PURPOSE: We hypothesized that neurally adjusted ventilatory assist (NAVA) compared to conventional lung-protective mechanical ventilation (MV) decreases duration of MV and mortality in patients with acute respiratory failure (ARF). METHODS: We carried out a multicenter, randomized, controlled trial in patients with ARF from several etiologies. Intubated patients ventilated for ≤ 5 days expected to require MV for ≥ 72 h and able to breathe spontaneously were eligible for enrollment. Eligible patients were randomly assigned based on balanced treatment assignments with a computerized randomization allocation sequence to two ventilatory strategies: (1) lung-protective MV (control group), and (2) lung-protective MV with NAVA (NAVA group). Allocation concealment was maintained at all sites during the trial. Primary outcome was the number of ventilator-free days (VFDs) at 28 days. Secondary outcome was all-cause hospital mortality. All analyses were done according to the intention-to-treat principle. RESULTS: Between March 2014 and October 2019, we enrolled 306 patients and randomly assigned 153 patients to the NAVA group and 153 to the control group. Median VFDs were higher in the NAVA than in the control group (22 vs. 18 days; between-group difference 4 days; 95% confidence interval [CI] 0 to 8 days; p = 0.016). At hospital discharge, 39 (25.5%) patients in the NAVA group and 47 (30.7%) patients in the control group had died (between-group difference - 5.2%, 95% CI - 15.2 to 4.8, p = 0.31). Other clinical, physiological or safety outcomes did not differ significantly between the trial groups. CONCLUSION: NAVA decreased duration of MV although it did not improve survival in ventilated patients with ARF.


Assuntos
Suporte Ventilatório Interativo , Síndrome do Desconforto Respiratório , Insuficiência Respiratória , Humanos , Respiração Artificial , Síndrome do Desconforto Respiratório/terapia , Insuficiência Respiratória/terapia , Ventiladores Mecânicos
20.
Sensors (Basel) ; 20(7)2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32260312

RESUMO

This paper analyzes, through computational simulations, which spectral filters increase the number of discernible colors (NODC) of subjects with normal color vision, as well as red-green anomalous trichromats and dichromats. The filters are selected from a set of filters in which we have modeled spectral transmittances. With the selected filters we have carried out simulations performed using the spectral reflectances captured either by a hyperspectral camera or by a spectrometer. We have also studied the effects of these filters on color coordinates. Finally, we have simulated the results of two widely used color blindness tests: Ishihara and Farnsworth-Munsell 100 Hue (FM100). In these analyses the selected filters are compared with the commercial filters from EnChroma and VINO companies. The results show that the increase in NODC with the selected filters is not relevant. The simulation results show that none of these chosen filters help color vision deficiency (CVD) subjects to pass the set of color blindness tests studied. These results obtained using standard colorimetry support the hypothesis that the use of color filters does not cause CVDs to have a perception similar to that of a normal observer.


Assuntos
Percepção de Cores/fisiologia , Defeitos da Visão Cromática/reabilitação , Óptica e Fotônica/métodos , Defeitos da Visão Cromática/patologia , Filtração , Humanos , Dispositivos Ópticos , Óptica e Fotônica/instrumentação
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