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1.
Sensors (Basel) ; 24(2)2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38257418

RESUMEN

Fusarium graminearum and F. culmorum are considered some of the most dangerous pathogens of plant diseases. They are also considerably dangerous to humans as they contaminate stored grain, causing a reduction in yield and deterioration in grain quality by producing mycotoxins. Detecting Fusarium fungi is possible using various diagnostic methods. In the manuscript, qPCR tests were used to determine the level of wheat grain spoilage by estimating the amount of DNA present. High-performance liquid chromatography was performed to determine the concentration of DON and ZEA mycotoxins produced by the fungi. GC-MS analysis was used to identify volatile organic components produced by two studied species of Fusarium. A custom-made, low-cost, electronic nose was used for measurements of three categories of samples, and Random Forests machine learning models were trained for classification between healthy and infected samples. A detection performance with recall in the range of 88-94%, precision in the range of 90-96%, and accuracy in the range of 85-93% was achieved for various models. Two methods of data collection during electronic nose measurements were tested and compared: sensor response to immersion in the odor and response to sensor temperature modulation. An improvement in the detection performance was achieved when the temperature modulation profile with short rectangular steps of heater voltage change was applied.


Asunto(s)
Fusarium , Micotoxinas , Humanos , Triticum , Nariz Electrónica , Cromatografía de Gases y Espectrometría de Masas , Hongos , Grano Comestible
2.
Perception ; 51(8): 521-538, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35542977

RESUMEN

Making new acquaintances requires learning to recognise previously unfamiliar faces. In the current study, we investigated this process by staging real-world social interactions between actors and the participants. Participants completed a face-matching behavioural task in which they matched photographs of the actors (whom they had yet to meet), or faces similar to the actors (henceforth called foils). Participants were then scanned using functional magnetic resonance imaging (fMRI) while viewing photographs of actors and foils. Immediately after exiting the scanner, participants met the actors for the first time and interacted with them for 10 min. On subsequent days, participants completed a second behavioural experiment and then a second fMRI scan. Prior to each session, actors again interacted with the participants for 10 min. Behavioural results showed that social interactions improved performance accuracy when matching actor photographs, but not foil photographs. The fMRI analysis revealed a difference in the neural response to actor photographs and foil photographs across all regions of interest (ROIs) only after social interactions had occurred. Our results demonstrate that short social interactions were sufficient to learn and discriminate previously unfamiliar individuals. Moreover, these learning effects were present in brain areas involved in face processing and memory.


Asunto(s)
Reconocimiento Facial , Interacción Social , Encéfalo , Mapeo Encefálico , Reconocimiento Facial/fisiología , Hipocampo , Humanos , Imagen por Resonancia Magnética/métodos
3.
Molecules ; 27(20)2022 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-36296506

RESUMEN

Smoked cheeses are particularly popular among consumers for their flavor and aroma. Of interest, therefore, is the health aspect related to the likelihood of polycyclic aromatic hydrocarbons (PAHs), which are known carcinogens found in smoked products. Thus, the purpose of this study was to evaluate the occurrence of 15 polycyclic aromatic hydrocarbons (PAHs) in smoked and non-smoked cheeses purchased in Poland to monitor their safety. The level of selected PAHs in cheese samples was determined using the HPLC-DAD-FLD method. Most of the cheeses tested met the maximum level of benzo[a]pyrene (2 µg/kg) and the sum of benz[a]anthracene, chrysene, benzo[b]fluoranthene and benzo[a]pyrene (12 µg/kg) established for these products. However, all the cheeses studied in this work had relatively low amounts of the sum of these compounds compared to the information available in the cheese literature, ranging from

Asunto(s)
Queso , Fenantrenos , Hidrocarburos Policíclicos Aromáticos , Hidrocarburos Policíclicos Aromáticos/análisis , Crisenos , Humo , Cromatografía Líquida de Alta Presión , Benzo(a)pireno/análisis , Polonia , Acenaftenos , Fluorenos , Carcinógenos , Antracenos
4.
Molecules ; 26(12)2021 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-34205369

RESUMEN

The benefits of natural honeybee products (e.g., honey, royal jelly, beeswax, propolis, beevenom and pollen) to the immune system are remarkable, and many of them are involved in the induction of antibody production, maturation of immune cells and stimulation of the immune system. The type of plants in the geographical area, climatic conditions and production method have a significantly influence on the nutritional quality of honey. However, this variability can influence consumer liking by the sensory attributes of the product. The aim of this work was to compare the most popular honeys from Poland in terms of nutritional value, organoleptic properties and antioxidant activity. In the study, five varieties of honey (honeydew, forest, buckwheat, linden and dandelion) from conventional and organic production methods were tested. The nutritional characteristics of honey samples included acidity, content of water, sugars, vitamin C, HMF and phenolics (total and flavonoids), while honey color, taste, aroma and consistency were investigated in the organoleptic characteristics. The antioxidant activity was determined in water- and ethanol-soluble honey extracts using DPPH and ORAC tests. The results showed that organoleptic and nutritional characteristics of popular Polish honeys differ significantly in relation to plant source and production method. The significant effect of honey variety on the content of HMF, saccharose and phenolics, as well as acidity and antioxidant capacity were noted. The impact of variety and variety × production method interaction was significant in the case of the content of vitamin C, glucose and fructose. A visible difference of buckwheat and forest honeys from other samples was observed. The highest content of total phenolics with antioxidant activity based on the SET mechanism was found in buckwheat honeys, while forest honeys were richer in flavonoids.


Asunto(s)
Antioxidantes/farmacología , Abejas/metabolismo , Miel/análisis , Nutrientes/farmacología , Animales , Ácido Ascórbico/farmacología , Etanol/química , Fagopyrum , Femenino , Flavonoides/farmacología , Fructosa/farmacología , Glucosa/farmacología , Sistema Inmunológico/efectos de los fármacos , Masculino , Fenoles/farmacología , Polonia , Agua/química
5.
Molecules ; 26(2)2021 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-33467103

RESUMEN

Trichothecene mycotoxins are sesquiterpenoid compounds primarily produced by fungi in taxonomical genera such as Fusarium, Myrothecium, Stachybotrys, Trichothecium, and others, under specific climatic conditions on a worldwide basis. Fusarium mold is a major plant pathogen and produces a number of trichothecene mycotoxins including deoxynivalenol (or vomitoxin), nivalenol, diacetoxyscirpenol, and T-2 toxin, HT-2 toxin. Monogastrics are sensitive to vomitoxin, while poultry and ruminants appear to be less sensitive to some trichothecenes through microbial metabolism of trichothecenes in the gastrointestinal tract. Trichothecene mycotoxins occur worldwide however both total concentrations and the particular mix of toxins present vary with environmental conditions. Proper agricultural practices such as avoiding late harvests, removing overwintered stubble from fields, and avoiding a corn/wheat rotation that favors Fusarium growth in residue can reduce trichothecene contamination of grains. Due to the vague nature of toxic effects attributed to low concentrations of trichothecenes, a solid link between low level exposure and a specific trichothecene is difficult to establish. Multiple factors, such as nutrition, management, and environmental conditions impact animal health and need to be evaluated with the knowledge of the mycotoxin and concentrations known to cause adverse health effects. Future research evaluating the impact of low-level exposure on livestock may clarify the potential impact on immunity. Trichothecenes are rapidly excreted from animals, and residues in edible tissues, milk, or eggs are likely negligible. In chronic exposures to trichothecenes, once the contaminated feed is removed and exposure stopped, animals generally have an excellent prognosis for recovery. This review shows the occurrence of trichothecenes in food and feed in 2011-2020 and their toxic effects and provides a summary of the discussions on the potential public health concerns specifically related to trichothecenes residues in foods associated with the exposure of farm animals to mycotoxin-contaminated feeds and impact to human health. Moreover, the article discusses the methods of their detection.


Asunto(s)
Alimentación Animal , Análisis de los Alimentos , Contaminación de Alimentos/análisis , Microbiología de Alimentos , Enfermedades Transmitidas por los Alimentos , Hongos Mitospóricos/crecimiento & desarrollo , Tricotecenos/envenenamiento , Alimentación Animal/análisis , Alimentación Animal/microbiología , Animales , Enfermedades Transmitidas por los Alimentos/metabolismo , Enfermedades Transmitidas por los Alimentos/microbiología , Enfermedades Transmitidas por los Alimentos/patología , Enfermedades Transmitidas por los Alimentos/prevención & control , Humanos
6.
Plant Foods Hum Nutr ; 75(2): 298-304, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32189232

RESUMEN

The study examined the effects of various methods of thermal treatment of Lord cultivar potato tubers on changes in starch, polyphenols, vitamin C, antioxidant activity, and mineral compounds. Following heat treatment in order to determine further transformations of starch, the potatoes were stored at 2 °C/24 h. Changes in starch, bioactive compounds and antioxidant properties varied depending on the treatment method. In general, higher retention of bioactive compounds was noted for tubers treated with "dry" methods, such as microwaving or grilling than for tubers treated with "wet" methods, e.g., boiling in water, steam cooking or cooking in a combi oven. These samples were also characterised by a higher resistant starch content. Cold storage resulted in an increase in the proportion of resistant starch. Total phenols content ranged from 210.96 (boiling) to 348.46 mg/100 g DW (grilling) and vitamin C content ranged from 43.79 (boiling) to 68.83 mg/100 g DW (microwaving). DPPH radical scavenging activity was the highest for the grilled tubers. The results indicate microwaving and grilling as the most favourable thermal treatments of potato.


Asunto(s)
Solanum tuberosum , Ácido Ascórbico , Culinaria , Tubérculos de la Planta , Almidón
7.
Neuroimage ; 202: 116084, 2019 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-31400530

RESUMEN

Perception via different sensory modalities was traditionally believed to be supported by largely separate brain systems. However, a growing number of studies demonstrate that the visual cortices of typical, sighted adults are involved in tactile and auditory perceptual processing. Here, we investigated the spatiotemporal dynamics of the visual cortex's involvement in a complex tactile task: Braille letter recognition. Sighted subjects underwent Braille training and then participated in a transcranial magnetic stimulation (TMS) study in which they tactually identified single Braille letters. During this task, TMS was applied to their left early visual cortex, visual word form area (VWFA), and left early somatosensory cortex at five time windows from 20 to 520 ms following the Braille letter presentation's onset. The subjects' response accuracy decreased when TMS was applied to the early visual cortex at the 120-220 ms time window and when TMS was applied to the VWFA at the 320-420 ms time window. Stimulation of the early somatosensory cortex did not have a time-specific effect on the accuracy of the subjects' Braille letter recognition, but rather caused a general slowdown during this task. Our results indicate that the involvement of sighted people's visual cortices in tactile perception respects the canonical visual hierarchy-the early tactile processing stages involve the early visual cortex, whereas more advanced tactile computations involve high-level visual areas. Our findings are compatible with the metamodal account of brain organization and suggest that the whole visual cortex may potentially support spatial perception in a task-specific, sensory-independent manner.


Asunto(s)
Corteza Somatosensorial/fisiología , Percepción del Tacto/fisiología , Corteza Visual/fisiología , Femenino , Humanos , Estimulación Magnética Transcraneal , Adulto Joven
8.
J Neurosci ; 37(32): 7606-7618, 2017 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-28676576

RESUMEN

It is well established that networks within multiple-demand cortex (MDC) become active when diverse skills and behaviors are being learnt. However, their causal role in learning remains to be established. In the present study, we first performed functional magnetic resonance imaging on healthy female and male human participants to confirm that MDC was most active in the initial stages of learning a novel vocabulary, consisting of pronounceable nonwords (pseudowords), each associated with a picture of a real object. We then examined, in healthy female and male human participants, whether repetitive transcranial magnetic stimulation of a frontal midline node of the cingulo-opercular MDC affected learning rates specifically during the initial stages of learning. We report that stimulation of this node, but not a control brain region, substantially improved both accuracy and response times during the earliest stage of learning pseudoword-object associations. This stimulation had no effect on the processing of established vocabulary, tested by the accuracy and response times when participants decided whether a real word was accurately paired with a picture of an object. These results provide evidence that noninvasive stimulation to MDC nodes can enhance learning rates, thereby demonstrating their causal role in the learning process. We propose that this causal role makes MDC candidate target for experimental therapeutics; for example, in stroke patients with aphasia attempting to reacquire a vocabulary.SIGNIFICANCE STATEMENT Learning a task involves the brain system within which that specific task becomes established. Therefore, successfully learning a new vocabulary establishes the novel words in the language system. However, there is evidence that in the early stages of learning, networks within multiple-demand cortex (MDC), which control higher cognitive functions, such as working memory, attention, and monitoring of performance, become active. This activity declines once the task is learnt. The present study demonstrated that a node within MDC, located in midline frontal cortex, becomes active during the early stage of learning a novel vocabulary. Importantly, noninvasive brain stimulation of this node improved performance during this stage of learning. This observation demonstrated that MDC activity is important for learning.


Asunto(s)
Estimulación Acústica/métodos , Corteza Cerebral/fisiología , Estimulación Luminosa/métodos , Tiempo de Reacción/fisiología , Aprendizaje Verbal/fisiología , Vocabulario , Adulto , Anciano , Aprendizaje por Asociación/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Distribución Aleatoria , Estimulación Magnética Transcraneal/métodos , Adulto Joven
9.
Neuroimage ; 183: 394-400, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30130641

RESUMEN

Prior studies demonstrate that a face-responsive region in the posterior superior temporal sulcus (pSTS) is involved in facial expression recognition. Although this region can be identified in both hemispheres, studies more commonly report it in the right hemisphere. However, the extent to which expression recognition is lateralised in pSTS remains unclear. In the current study, we used transcranial magnetic stimulation (TMS) to systematically compare the causal contribution of the right pSTS (rpSTS) with the left pSTS (lpSTS) during facial expression recognition. TMS was delivered over the functionally localised rpSTS, lpSTS and the control vertex site while participants (N = 30) performed an expression matching task and a control object matching task. TMS delivered over the rpSTS impaired expression recognition more than TMS delivered over the lpSTS. Crucially, TMS delivered over the rpSTS and lpSTS impaired task performance more than TMS delivered over the control site. TMS had no effect on the control task. This causally demonstrates that while task disruption was greater in the rpSTS, both the rpSTS and the lpSTS were engaged in facial expression recognition. Our results indicate that cognitive functions that are seemingly lateralised in neuroimaging studies, still rely on computations performed in both hemispheres for optimum task performance.


Asunto(s)
Expresión Facial , Reconocimiento Facial/fisiología , Lateralidad Funcional/fisiología , Lóbulo Temporal/fisiología , Estimulación Magnética Transcraneal/métodos , Adolescente , Adulto , Femenino , Humanos , Masculino , Adulto Joven
10.
J Sci Food Agric ; 97(4): 1316-1325, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27342385

RESUMEN

BACKGROUND: Vodka is a spirit-based beverage made from ethyl alcohol of agricultural origin. At present, increasingly more vodka brands have labels that specify the botanical origin of the product. Until now, the techniques for distinguishing between vodkas of different botanical origin have been costly, time-consuming and insufficient for making a distinction between vodka produced from similar raw materials. Therefore, it is of utmost importance to find a fast and relatively inexpensive technique for conducting such tests. RESULTS: In the present study, we employed comprehensive two-dimensional gas chromatography (GC×GC) and an electronic nose based on the technology of ultra-fast GC with chemometric methods such as partial least square discriminant analysis, discriminant function analysis and soft independent modeling of class analogy. CONCLUSION: Both techniques allow a distinction between the vodkas produced from different raw materials. In the case of GC×GC, the differences between vodkas were more noticeable than in the analysis by electronic nose; however, the electronic nose allowed the significantly faster analysis of vodkas. © 2016 Society of Chemical Industry.


Asunto(s)
Bebidas Alcohólicas/análisis , Cromatografía de Gases/métodos , Nariz Electrónica , Odorantes/análisis , Plantas/química , Compuestos Orgánicos Volátiles/análisis , Análisis Discriminante , Grano Comestible/química , Etiquetado de Alimentos , Humanos , Análisis de los Mínimos Cuadrados , Modelos Biológicos , Modelos Estadísticos , Tubérculos de la Planta/química , Poaceae/química , Análisis de Componente Principal , Solanum tuberosum/química , Especificidad de la Especie
12.
Sensors (Basel) ; 16(10)2016 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-27735832

RESUMEN

The capability of a phthalocyanine-based voltammetric electronic tongue to analyze strong alcoholic beverages has been evaluated and compared with the performance of spectroscopic techniques coupled to chemometrics. Nalewka Polish liqueurs prepared from five apple varieties have been used as a model of strong liqueurs. Principal Component Analysis has demonstrated that the best discrimination between liqueurs prepared from different apple varieties is achieved using the e-tongue and UV-Vis spectroscopy. Raman spectra coupled to chemometrics have not been efficient in discriminating liqueurs. The calculated Euclidean distances and the k-Nearest Neighbors algorithm (kNN) confirmed these results. The main advantage of the e-tongue is that, using PLS-1, good correlations have been found simultaneously with the phenolic content measured by the Folin-Ciocalteu method (R² of 0.97 in calibration and R² of 0.93 in validation) and also with the density, a marker of the alcoholic content method (R² of 0.93 in calibration and R² of 0.88 in validation). UV-Vis coupled with chemometrics has shown good correlations only with the phenolic content (R² of 0.99 in calibration and R² of 0.99 in validation) but correlations with the alcoholic content were low. Raman coupled with chemometrics has shown good correlations only with density (R² of 0.96 in calibration and R² of 0.85 in validation). In summary, from the three holistic methods evaluated to analyze strong alcoholic liqueurs, the voltammetric electronic tongue using phthalocyanines as sensing elements is superior to Raman or UV-Vis techniques because it shows an excellent discrimination capability and remarkable correlations with both antioxidant capacity and alcoholic content-the most important parameters to be measured in this type of liqueurs.

13.
J Cogn Neurosci ; 27(3): 593-604, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25244114

RESUMEN

This study investigated how the left inferior parietal lobule (IPL) contributes to visual word recognition. We used repetitive TMS to temporarily disrupt neural information processing in two anatomical fields of the IPL, namely, the angular (ANG) and supramarginal (SMG) gyri, and observed the effects on reading tasks that focused attention on either the meaning or sounds of written words. Relative to no TMS, stimulation of the left ANG selectively slowed responses in the meaning, but not sound, task, whereas stimulation of the left SMG affected responses in the sound, but not meaning, task. These results demonstrate that ANG and SMG doubly dissociate in their contributions to visual word recognition. We suggest that this functional division of labor may be understood in terms of the distinct patterns of cortico-cortical connectivity resulting in separable functional circuits.


Asunto(s)
Lóbulo Parietal/fisiología , Reconocimiento Visual de Modelos/fisiología , Lectura , Estimulación Magnética Transcraneal/métodos , Adolescente , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Adulto Joven
14.
Sensors (Basel) ; 13(4): 5008-27, 2013 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-23591962

RESUMEN

The paper presents the potential of an electronic nose technique in the field of fast diagnostics of patients suspected of Chronic Obstructive Pulmonary Disease (COPD). The investigations were performed using a simple electronic nose prototype equipped with a set of six semiconductor sensors manufactured by FIGARO Co. They were aimed at verification of a possibility of differentiation between model reference mixtures with potential COPD markers (N,N-dimethylformamide and N,N-dimethylacetamide). These mixtures contained volatile organic compounds (VOCs) such as acetone, isoprene, carbon disulphide, propan-2-ol, formamide, benzene, toluene, acetonitrile, acetic acid, dimethyl ether, dimethyl sulphide, acrolein, furan, propanol and pyridine, recognized as the components of exhaled air. The model reference mixtures were prepared at three concentration levels-10 ppb, 25 ppb, 50 ppb v/v-of each component, except for the COPD markers. Concentration of the COPD markers in the mixtures was from 0 ppb to 100 ppb v/v. Interpretation of the obtained data employed principal component analysis (PCA). The investigations revealed the usefulness of the electronic device only in the case when the concentration of the COPD markers was twice as high as the concentration of the remaining components of the mixture and for a limited number of basic mixture components.


Asunto(s)
Biomarcadores/análisis , Nariz Electrónica , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Gases/análisis , Humanos , Análisis de Componente Principal , Estándares de Referencia , Procesamiento de Señales Asistido por Computador , Volatilización
15.
Soc Cogn Affect Neurosci ; 18(1)2023 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-38048419

RESUMEN

Recognizing facial expressions is dependent on multiple brain networks specialized for different cognitive functions. In the current study, participants (N = 20) were scanned using functional magnetic resonance imaging (fMRI), while they performed a covert facial expression naming task. Immediately prior to scanning thetaburst transcranial magnetic stimulation (TMS) was delivered over the right lateral prefrontal cortex (PFC), or the vertex control site. A group whole-brain analysis revealed that TMS induced opposite effects in the neural responses across different brain networks. Stimulation of the right PFC (compared to stimulation of the vertex) decreased neural activity in the left lateral PFC but increased neural activity in three nodes of the default mode network (DMN): the right superior frontal gyrus, right angular gyrus and the bilateral middle cingulate gyrus. A region of interest analysis showed that TMS delivered over the right PFC reduced neural activity across all functionally localised face areas (including in the PFC) compared to TMS delivered over the vertex. These results suggest that visually recognizing facial expressions is dependent on the dynamic interaction of the face-processing network and the DMN. Our study also demonstrates the utility of combined TMS/fMRI studies for revealing the dynamic interactions between different functional brain networks.


Asunto(s)
Lóbulo Temporal , Estimulación Magnética Transcraneal , Humanos , Estimulación Magnética Transcraneal/métodos , Lóbulo Temporal/fisiología , Expresión Facial , Red en Modo Predeterminado , Mapeo Encefálico/métodos , Corteza Prefrontal/diagnóstico por imagen , Corteza Prefrontal/fisiología , Imagen por Resonancia Magnética/métodos
16.
Soc Cogn Affect Neurosci ; 18(1)2023 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-37837305

RESUMEN

Social categories such as the race or ethnicity of an individual are typically conveyed by the visual appearance of the face. The aim of this study was to explore how these differences in facial appearance are represented in human and artificial neural networks. First, we compared the similarity of faces from different races using a neural network trained to discriminate identity. We found that the differences between races were most evident in the fully connected layers of the network. Although these layers were also able to predict behavioural judgements of face identity from human participants, performance was biased toward White faces. Next, we measured the neural response in face-selective regions of the human brain to faces from different races in Asian and White participants. We found distinct patterns of response to faces from different races in face-selective regions. We also found that the spatial pattern of response was more consistent across participants for own-race compared to other-race faces. Together, these findings show that faces from different races elicit different patterns of response in human and artificial neural networks. These differences may underlie the ability to make categorical judgements and explain the behavioural advantage for the recognition of own-race faces.


Asunto(s)
Encéfalo , Reconocimiento en Psicología , Humanos , Pueblo Asiatico , Etnicidad , Cara , Reconocimiento Visual de Modelos/fisiología , Reconocimiento en Psicología/fisiología , Población Blanca
17.
Comput Methods Programs Biomed ; 240: 107684, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37356354

RESUMEN

BACKGROUND: When the COVID-19 pandemic commenced in 2020, scientists assisted medical specialists with diagnostic algorithm development. One scientific research area related to COVID-19 diagnosis was medical imaging and its potential to support molecular tests. Unfortunately, several systems reported high accuracy in development but did not fare well in clinical application. The reason was poor generalization, a long-standing issue in AI development. Researchers found many causes of this issue and decided to refer to them as confounders, meaning a set of artefacts and methodological errors associated with the method. We aim to contribute to this steed by highlighting an undiscussed confounder related to image resolution. METHODS: 20 216 chest X-ray images (CXR) from worldwide centres were analyzed. The CXRs were bijectively projected into the 2D domain by performing Uniform Manifold Approximation and Projection (UMAP) embedding on the radiomic features (rUMAP) or CNN-based neural features (nUMAP) from the pre-last layer of the pre-trained classification neural network. Additional 44 339 thorax CXRs were used for validation. The comprehensive analysis of the multimodality of the density distribution in rUMAP/nUMAP domains and its relation to the original image properties was used to identify the main confounders. RESULTS: nUMAP revealed a hidden bias of neural networks towards the image resolution, which the regular up-sampling procedure cannot compensate for. The issue appears regardless of the network architecture and is not observed in a high-resolution dataset. The impact of the resolution heterogeneity can be partially diminished by applying advanced deep-learning-based super-resolution networks. CONCLUSIONS: rUMAP and nUMAP are great tools for image homogeneity analysis and bias discovery, as demonstrated by applying them to COVID-19 image data. Nonetheless, nUMAP could be applied to any type of data for which a deep neural network could be constructed. Advanced image super-resolution solutions are needed to reduce the impact of the resolution diversity on the classification network decision.


Asunto(s)
COVID-19 , Aprendizaje Profundo , Humanos , COVID-19/diagnóstico por imagen , Prueba de COVID-19 , Pandemias , Artefactos
18.
Sci Data ; 10(1): 348, 2023 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-37268643

RESUMEN

The outbreak of the SARS-CoV-2 pandemic has put healthcare systems worldwide to their limits, resulting in increased waiting time for diagnosis and required medical assistance. With chest radiographs (CXR) being one of the most common COVID-19 diagnosis methods, many artificial intelligence tools for image-based COVID-19 detection have been developed, often trained on a small number of images from COVID-19-positive patients. Thus, the need for high-quality and well-annotated CXR image databases increased. This paper introduces POLCOVID dataset, containing chest X-ray (CXR) images of patients with COVID-19 or other-type pneumonia, and healthy individuals gathered from 15 Polish hospitals. The original radiographs are accompanied by the preprocessed images limited to the lung area and the corresponding lung masks obtained with the segmentation model. Moreover, the manually created lung masks are provided for a part of POLCOVID dataset and the other four publicly available CXR image collections. POLCOVID dataset can help in pneumonia or COVID-19 diagnosis, while the set of matched images and lung masks may serve for the development of lung segmentation solutions.


Asunto(s)
COVID-19 , Aprendizaje Profundo , Radiografía Torácica , Rayos X , Humanos , Algoritmos , Inteligencia Artificial , COVID-19/diagnóstico por imagen , Prueba de COVID-19 , Neumonía , Polonia , Radiografía Torácica/métodos , SARS-CoV-2
19.
Cereb Cortex Commun ; 3(3): tgac036, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36159205

RESUMEN

Neuroimaging studies identify multiple face-selective areas in the human brain. In the current study, we compared the functional response of the face area in the lateral prefrontal cortex to that of other face-selective areas. In Experiment 1, participants (n = 32) were scanned viewing videos containing faces, bodies, scenes, objects, and scrambled objects. We identified a face-selective area in the right inferior frontal gyrus (rIFG). In Experiment 2, participants (n = 24) viewed the same videos or static images. Results showed that the rIFG, right posterior superior temporal sulcus (rpSTS), and right occipital face area (rOFA) exhibited a greater response to moving than static faces. In Experiment 3, participants (n = 18) viewed face videos in the contralateral and ipsilateral visual fields. Results showed that the rIFG and rpSTS showed no visual field bias, while the rOFA and right fusiform face area (rFFA) showed a contralateral bias. These experiments suggest two conclusions; firstly, in all three experiments, the face area in the IFG was not as reliably identified as face areas in the occipitotemporal cortex. Secondly, the similarity of the response profiles in the IFG and pSTS suggests the areas may perform similar cognitive functions, a conclusion consistent with prior neuroanatomical and functional connectivity evidence.

20.
Animals (Basel) ; 12(2)2022 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-35049820

RESUMEN

The aim of the study was to compare and demonstrate whether commercial rennet ripening cheeses available on the market in summer and winter differ in their chemical composition, fatty acid profile, content of cis9trans11 C18:2 (CLA) acid and other trans isomers of C18:1 and C18:2 acid and whether they are characterized by different values of lipid quality assessment indices. The experimental material consisted of rennet ripening of cheeses produced from cow's milk available in the Polish market. The first batch contained cheeses produced in winter and purchased from the market between May and June. The second batch contained cheeses produced in summer and purchased between November and December. Chemical composition was analyzed by FoodScan apparatus. The gas chromatography (GC) method was used to determine the content of fatty acids. Results obtained in the presented study indicate that the chemical composition, content of fatty acids trans isomers, and lipid quality indices varied between summer and winter cheeses. The summer cheeses were richer sources of MUFA and PUFA compared to winter cheeses. Summer cheeses were also characterized by lower content of SFA, higher content n - 3, lower n - 6/n - 3 ratio, and higher content of DFA. Higher contents of CLA and trans C18:1 and C18:2 were found in summer cheeses.

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