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1.
Sensors (Basel) ; 23(15)2023 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-37571700

RESUMEN

This study investigated the use of affect and physiological signals of heart rate, electrodermal activity, pupil dilation, and skin temperature to classify advertising engagement. The ground truth for the affective and behavioral aspects of ad engagement was collected from 53 young adults using the User Engagement Scale. Three gradient-boosting classifiers, LightGBM (LGBM), HistGradientBoostingClassifier (HGBC), and XGBoost (XGB), were used along with signal fusion to evaluate the performance of different signal combinations as predictors of engagement. The classifiers trained on the fusion of skin temperature, valence, and tiredness (features n = 5) performed better than those trained on all signals (features n = 30). The average AUC ROC scores for the fusion set were XGB = 0.68 (0.10), LGBM = 0.69 (0.07), and HGBC = 0.70 (0.11), compared to the lower scores for the set of all signals (XGB = 0.65 (0.11), LGBM = 0.66 (0.11), HGBC = 0.64 (0.10)). The results also show that the signal fusion set based on skin temperature outperforms the fusion sets of the other three signals. The main finding of this study is the role of specific physiological signals and how their fusion aids in more effective modeling of ad engagement while reducing the number of features.


Asunto(s)
Publicidad , Adulto Joven , Humanos , Frecuencia Cardíaca/fisiología
2.
Sensors (Basel) ; 22(7)2022 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-35408315

RESUMEN

The purpose of this study is to analyse data from the marine pilots' bio-sensor readings to determine how experience affects their biometrical response during the port approach. The experiences play a significant role in the participant's decision-making process and correlate with the repetitions. Through the repetitions of the experimental task, the participants gain experience, which correlates with the biometrical response, e.g., heart rate, electrodermal activity, etc. After exposing the two experience-distinct groups of participants to the same simulated port-approaching task, their collected biometric data is analysed and discussed. The results show that biometrical readings of the less experienced participants typically vary compared to that of the experienced participants, who take the simulated task more seriously. The study also yields insight into the workload process, involving disturbing factors during the task.


Asunto(s)
Medicina Aeroespacial , Análisis y Desempeño de Tareas , Biometría , Frecuencia Cardíaca/fisiología , Humanos , Carga de Trabajo
3.
Lab Anim ; 55(1): 43-52, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32419577

RESUMEN

Experimental murine models are an essential tool in the field of bone marrow (BM) transplantation research. Therefore, numerous mice are required to obtain a sufficient number of BM cells, which is in contrast with the Reduction principle of the 3R principles. The selection of the cell source and the isolation protocol are therefore critical in obtaining a sufficient yield of cells for experiments. Nowadays, the vertebrae are already used as an extra source of BM cells to enrich the number of isolated cells from the long bones and ilia (LBI), when needed. Yet, little is known if BM cells from LBI and vertebrae share the same characteristics and can be pooled together for further analysis. Therefore, in this study, we aimed to compare the quantity and characteristics of haematopoietic and stromal cell lines in the BM from the LBI and vertebrae. To count haematopoietic and mesenchymal stem/stromal progenitors, colony-forming unit assays were performed. To determine the expansion capacity of mesenchymal stem/stromal cells (MSCs), cultivation of MSCs and measurement of the expression of surface markers by flow cytometry was performed. The characterisation and enumeration of immune cell populations was also performed by flow cytometry. Here, we show that the vertebrae are a comparable source of BM cells to the LBI regarding the analysed parameters.


Asunto(s)
Alternativas a las Pruebas en Animales/normas , Células de la Médula Ósea/fisiología , Células Madre Mesenquimatosas/fisiología , Columna Vertebral/fisiología , Animales , Femenino , Masculino , Ratones , Ratones Endogámicos BALB C
4.
Sensors (Basel) ; 20(17)2020 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-32825013

RESUMEN

This work examines the differences between a human and a machine in object recognition tasks. The machine is useful as much as the output classification labels are correct and match the dataset-provided labels. However, very often a discrepancy occurs because the dataset label is different than the one expected by a human. To correct this, the concept of the target user population is introduced. The paper presents a complete methodology for either adapting the output of a pre-trained, state-of-the-art object classification algorithm to the target population or inferring a proper, user-friendly categorization from the target population. The process is called 'user population re-targeting'. The methodology includes a set of specially designed population tests, which provide crucial data about the categorization that the target population prefers. The transformation between the dataset-bound categorization and the new, population-specific categorization is called the 'Cognitive Relevance Transform'. The results of the experiments on the well-known datasets have shown that the target population preferred such a transformed categorization by a large margin, that the performance of human observers is probably better than previously thought, and that the outcome of re-targeting may be difficult to predict without actual tests on the target population.


Asunto(s)
Algoritmos , Cognición , Percepción Visual , Humanos
5.
Vasc Health Risk Manag ; 12: 305-11, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27536125

RESUMEN

In occidental countries, peripheral arterial disease (PAD) is an important health issue; however, most subjects are asymptomatic (~50%) and therefore undiagnosed and untreated. Current guidelines recommend screening for PAD in primary care setting using ankle brachial index (ABI) in all patients with cardiovascular risks. This is, however, not performed strictly because the standard Doppler method is cumbersome and time-consuming. Here, we evaluate the accuracy and reproducibility of ABI measurements obtained by an improved automated oscillometric device, the MESI ABPI MD(®) device, and the standard Doppler method. ABI was measured in random order in a general practice with Doppler probes by two operators separately (ABI_dop) and twice with the MESI ABPI MD device (ABI_mesi). ABI_dop was calculated dividing the highest systolic blood pressure from both tibial and dorsalis pedis arteries by the highest systolic blood pressure of both brachial arteries. ABI_mesi was obtained automatically with simultaneous measurements on three extremities. According to ABI_dop, PAD was present in 10% of the 136 screened subjects (68.2±7.4 years). Interoperator coefficient of variation was 5.5% for ABI_dop, while the intrasubject coefficient of variation for ABI_mesi was 3.0%. ABI_mesi was correlated with ABI_dop (R=0.61, P<0.0001). The difference between the two techniques was 0.06±0.14 with ABI_mesi providing slightly higher values (P<0.0001) and negligible bias across the range (R=0.19, P<0.0001). Therefore, ABI_mesi ≤1 had a sensitivity of 85% and specificity of 96% to detect ABI_dop ≤0.9 and hence PAD. Doppler measurements took seven times longer than MESI ABPI MD measurements to be performed. In conclusion, MESI improved automated oscillometric method and offered a faster and repeatable measurement of ABI with only a small, clinically irrelevant overestimation of ABI value. The tested MESI ABPI MD-improved oscillometric system can be used as a screening tool for patients in general practice and would enable family doctors to comply with current guidelines for PAD.


Asunto(s)
Índice Tobillo Braquial/instrumentación , Índice Tobillo Braquial/métodos , Presión Sanguínea , Enfermedad Arterial Periférica/diagnóstico , Ultrasonografía Doppler , Anciano , Automatización , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oscilometría/instrumentación , Enfermedad Arterial Periférica/fisiopatología , Pletismografía/instrumentación , Valor Predictivo de las Pruebas , Distribución Aleatoria , Reproducibilidad de los Resultados , Factores de Tiempo , Estudios de Tiempo y Movimiento
6.
PLoS One ; 8(12): e81703, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24349116

RESUMEN

BACKGROUND: The aim of our study was to evaluate the prognostic value of glomerular and tubular proteinuria and tubular enzymuria as early indicators of therapeutic response to induction therapy with i.v. pulse cyclophosphamide (CyC) and methylprednisolone (MP) in patients with antineutrophil cytoplasmic antibody (ANCA) associated glomerulonephritis. METHODS AND FINDINGS: An observational single-center study was conducted in 30 patients with ANCA-associated glomerulonephritis. Patients were divided into subgroups with good or poor response to CyC therapy according to clinical and laboratory parameters. The diagnosis of ANCA-associated glomerulonephritis was based on the Chapel-Hill disease definitions. Good response to induction therapy was significantly associated with higher absolute values of urine N-acetyl-beta-D-glucosaminidase (NAG) to creatinine ratio (above 14.83 microcat/mol) and urine immunoglobulin G (IgG) to albumin ratio (above 0.09) at the time of diagnosis, while albuminuria or proteinuria did not have any early predictive value. The remission of renal disease was anticipated as early as 3 months after introduction of induction therapy in patients with reduction of urine NAG to creatinine ratio below the baseline value and in patients with at least 24% rise in eGFR. CONCLUSIONS: Urine IgG to albumin and urine NAG to creatinine ratio are better early predictors of treatment response in patients with ANCA-associated glomerulonephritis than proteinuria or albuminuria.


Asunto(s)
Acetilglucosaminidasa/orina , Anticuerpos Anticitoplasma de Neutrófilos/inmunología , Glomerulonefritis/tratamiento farmacológico , Glomerulonefritis/orina , Inmunoglobulina G/orina , Albúmina Sérica/metabolismo , Anciano , Albuminuria/diagnóstico , Anticuerpos Anticitoplasma de Neutrófilos/metabolismo , Biomarcadores/orina , Ciclofosfamida/uso terapéutico , Femenino , Glomerulonefritis/diagnóstico , Glomerulonefritis/inmunología , Glucocorticoides/uso terapéutico , Humanos , Inmunosupresores/uso terapéutico , Masculino , Metilprednisolona/uso terapéutico , Persona de Mediana Edad , Pronóstico , Resultado del Tratamiento
7.
Artif Intell Med ; 58(2): 101-14, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23548472

RESUMEN

OBJECTIVE: The early detection of breast cancer is one of the most important predictors in determining the prognosis for women with malignant tumours. Dynamic contrast-enhanced magnetic-resonance imaging (DCE-MRI) is an important imaging modality for detecting and interpreting the different breast lesions from a time sequence of images and has proved to be a very sensitive modality for breast-cancer diagnosis. However, DCE-MRI exhibits only a moderate specificity, thus leading to a high rate of false positives, resulting in unnecessary biopsies that are stressful and physically painful for the patient and lead to an increase in the cost of treatment. There is a strong medical need for a DCE-MRI computer-aided diagnosis tool that would offer a reliable support to the physician's decision providing a high level of sensitivity and specificity. METHODS: In our study we investigated the possibility of increasing differentiation between the malignant and the benign lesions with respect to the spatial variation of the temporal enhancements of three parametric maps, i.e., the initial enhancement (IE) map, the post-initial enhancement (PIE) map and the signal enhancement ratio (SER) map, by introducing additional methods along with the grey-level co-occurrence matrix, i.e., a second-order statistical method already applied for quantifying the spatiotemporal variations. We introduced the grey-level run-length matrix and the grey-level difference matrix, representing two additional, second-order statistical methods, and the circular Gabor as a frequency-domain-based method. Each of the additional methods is for the first time applied to the DCE-MRI data to differentiate between the malignant and the benign breast lesions. We applied the least-square minimum-distance classifier (LSMD), logistic regression and least-squares support vector machine (LS-SVM) classifiers on a total of 115 (78 malignant and 37 benign) breast DCE-MRI cases. The performances were evaluated using ten experiments of a ten-fold cross-validation. RESULTS: Our experimental analysis revealed the PIE map, together with the feature subset in which the discriminating ability of the co-occurrence features was increased by adding the newly introduced features, to be the most significant for differentiation between the malignant and the benign lesions. That diagnostic test - the aforementioned combination of parametric map and the feature subset achieved the sensitivity of 0.9193 which is statistically significantly higher compared to other diagnostic tests after ten-experiments of a ten-fold cross-validation and gave a statistically significantly higher specificity of 0.7819 for the fixed 95% sensitivity after the receiver operating characteristic (ROC) curve analysis. Combining the information from all the three parametric maps significantly increased the area under the ROC curve (AUC) of the aforementioned diagnostic test for the LSMD and logistic regression; however, not for the LS-SVM. The LSMD classifier yielded the highest area under the ROC curve when using the combined information, increasing the AUC from 0.9651 to 0.9755. CONCLUSION: Introducing new features to those of the grey-level co-occurrence matrix significantly increased the differentiation between the malignant and the benign breast lesions, thus resulting in a high sensitivity and improved specificity.


Asunto(s)
Inteligencia Artificial , Neoplasias de la Mama/diagnóstico , Medios de Contraste , Diagnóstico por Computador/métodos , Interpretación de Imagen Asistida por Computador , Imagen por Resonancia Magnética , Área Bajo la Curva , Neoplasias de la Mama/clasificación , Neoplasias de la Mama/patología , Técnicas de Apoyo para la Decisión , Detección Precoz del Cáncer , Femenino , Humanos , Análisis de los Mínimos Cuadrados , Modelos Logísticos , Valor Predictivo de las Pruebas , Curva ROC , Factores de Tiempo
8.
Histochem Cell Biol ; 139(1): 195-204, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23064788

RESUMEN

Immunocytochemistry is a powerful tool for detection and visualization of specific molecules in living or fixed cells, their localization and their relative abundance. One of the most commonly used fluorescent DNA dyes in immunocytochemistry applications is 4',6-diamidino-2-phenylindole dihydrochloride, known as DAPI. DAPI binds strongly to DNA and is used extensively for visualizing cell nuclei. It is excited by UV light and emits characteristic blue fluorescence. Here, we report a phenomenon based on an apparent photoconversion of DAPI that results in detection of a DAPI signal using a standard filter set for detection of green emission due to blue excitation. When a sample stained with DAPI only was first imaged with the green filter set (FITC/GFP), only a weak cytoplasmic autofluorescence was observed. Next, we imaged the sample with a DAPI filter set, obtaining a strong nuclear DAPI signal as expected. Upon reimaging the same samples with a FITC/GFP filter set, robust nuclear fluorescence was observed. We conclude that excitation with UV results in a photoconversion of DAPI that leads to detection of DAPI due to excitation and emission in the FITC/GFP channel. This phenomenon can affect data interpretation and lead to false-positive results when used together with fluorochrome-labeled nuclear proteins detected with blue excitation and green emission. In order to avoid misinterpretations, extra precaution should be taken to prepare staining solutions with low DAPI concentration and DAPI (UV excitation) images should be acquired after all other higher wavelength images. Of various DNA dyes tested, Hoechst 33342 exhibited the lowest photoconversion while that for DAPI and Hoechst 33258 was much stronger. Different fixation methods did not substantially affect the strength of photoconversion. We also suggest avoiding the use of mounting medium with high glycerol concentrations since glycerol showed the strongest impact on photoconversion. This photoconversion effect cannot be avoided even when using narrow bandpass filter sets.


Asunto(s)
Colorantes Fluorescentes/efectos de la radiación , Inmunohistoquímica/métodos , Indoles/efectos de la radiación , Procesos Fotoquímicos , Rayos Ultravioleta , Bencimidazoles/química , Bencimidazoles/efectos de la radiación , Bisbenzimidazol/química , Bisbenzimidazol/efectos de la radiación , Carcinoma Embrionario/metabolismo , Línea Celular Tumoral , Reacciones Falso Positivas , Fijadores/química , Colorantes Fluorescentes/química , Glicerol/química , Humanos , Indoles/química , Masculino , Microscopía Fluorescente , Reproducibilidad de los Resultados , Neoplasias Testiculares/patología
9.
Int J Pediatr Otorhinolaryngol ; 76(10): 1392-400, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22835930

RESUMEN

OBJECTIVE: To investigate the music perception abilities of prelingually deaf children with cochlear implants, in comparison to a group of normal-hearing children, and to consider the factors that contribute to music perception. METHODS: The music perception abilities of 39 prelingually deaf children with unilateral cochlear implants were compared to the abilities of 39 normal hearing children. To assess the music listening abilities, the MuSIC perception test was adopted. The influence of the child's age, age at implantation, device experience and type of sound-processing strategy on the music perception were evaluated. The effects of auditory performance, nonverbal intellectual abilities, as well as the child's additional musical education on music perception were also considered. RESULTS: Children with cochlear implants and normal hearing children performed significantly differently with respect to rhythm discrimination (55% vs. 82%, p<0.001), instrument identification (57% vs. 88%, p<0.001) and emotion rating (p=0.022). However we found no significant difference in terms of melody discrimination and dissonance rating between the two groups. There was a positive correlation between auditory performance and melody discrimination (r=0.27; p=0.031), between auditory performance and instrument identification (r=0.20; p=0.059) and between the child's grade (mark) in school music classes and melody discrimination (r=0.34; p=0.030). In children with cochlear implant only, the music perception ability assessed by the emotion rating test was negatively correlated to the child's age (r(S)=-0.38; p=0.001), age at implantation (r(S)=-0.34; p=0.032), and device experience (r(S)=-0.38; p=0.019). The child's grade in school music classes showed a positive correlation to music perception abilities assessed by rhythm discrimination test (r(S)=0.46; p<0.001), melody discrimination test (r(S)=0.28; p=0.018), and instrument identification test (r(S)=0.23; p=0.05). CONCLUSIONS: As expected, there was a marked difference in the music perception abilities of prelingually deaf children with cochlear implants in comparison to the group of normal hearing children, but not for all the tests of music perception. Additional multi-centre studies, including a larger number of participants and a broader spectrum of music subtests, considering as many as possible of the factors that may contribute to music perception, seem reasonable.


Asunto(s)
Percepción Auditiva , Implantes Cocleares , Sordera/cirugía , Música , Adolescente , Factores de Edad , Niño , Educación , Emociones , Femenino , Humanos , Masculino
10.
J Neurophysiol ; 105(4): 1950-62, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21307326

RESUMEN

The rodent whisker system has become the leading experimental paradigm for the study of active sensing. Thanks to more sophisticated behavioral paradigms, progressively better neurophysiological methods, and improved video hardware/software, there is now the prospect of defining the precise connection between the sensory apparatus and brain activity in awake, exploring animals. Achieving this ambitious goal requires quantitative, objective characterization of head and whisker kinematics. This study presents the methodology and potential uses of a new automated motion analysis routine. The program provides full quantification of head orientation and translation, as well as the angle, frequency, amplitude, and bilateral symmetry of whisking. The system operates without any need for manual tracing by the user. Quantitative comparison to whisker detection by expert humans indicates that the program's correct detection rate is at >95% even on animals with all whiskers intact. Particular attention has been paid to obtaining reliable performance under nonoptimal lighting or video conditions and at frame rates as low as 100. Variation of the zoom across time is compensated for without user intervention. The program adapts automatically to the size and shape of different species. The outcome of our testing indicates that the program can be a valuable tool in quantifying rodent sensorimotor behavior.


Asunto(s)
Conducta Animal/fisiología , Retroalimentación Sensorial/fisiología , Movimientos de la Cabeza/fisiología , Vibrisas/fisiología , Grabación en Video , Algoritmos , Animales , Fenómenos Biomecánicos , Masculino , Actividad Motora/fisiología , Ratas , Ratas Wistar
11.
J Telemed Telecare ; 13(7): 357-62, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17958938

RESUMEN

We have developed a telemedicine system for blood transfusion work, to supply the local hospital laboratory with an expert opinion from the central reference laboratory. The telemedicine system allows remote inspection and interpretation of pre-transfusion tests, which are performed by ID-cards (micro-tube gel technology). The system was installed at three blood transfusion laboratories in Slovenia, approximately 70 km apart. Validation of the telemedicine system was performed using 99 clinical cases selected randomly from routine work. Two groups of immunohaematology specialists participated. Group A (n = 8) performed the read-out of the pre-transfusion tests on ID-cards by using the telemedicine system. Group B (n = 2) then read the ID-cards independently using the standard visual method. All 98 final interpretations which were recorded using the telemedicine system were correct. We recorded 591 micro-tube read-outs of agglutination strength using the telemedicine system, of which 582 were correct. For comparison, we recorded 591 micro-tube read-outs using the standard visual method, of which 582 were correct. The validation proved that the telemedicine system was suitable for operational use.


Asunto(s)
Tipificación y Pruebas Cruzadas Sanguíneas/métodos , Transfusión Sanguínea , Telemedicina , Pruebas de Aglutinación/métodos , Humanos , Reproducibilidad de los Resultados , Eslovenia
12.
Transpl Immunol ; 14(3-4): 159-69, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15982558

RESUMEN

ABO histo-bloodgroups are strong transplantation antigens. In bone marrow transplantation, foreign ABO red cell antigens are not ignored by the immune system of the host, neither by the immunocompetent cells of the graft. Although ABO incompatibility is not considered a contraindication in bone marrow transplantation (BMT), its clinical consequences are still a matter of investigation. An overview of reports published by different groups is given and discussed. They present conflicting data regarding the role of the ABO match between patient and donor in the haematopoietic stem cell (HSC) transplantation. We report on the clinical outcome of bone marrow transplantation in 223 patients who received grafts from MHC identical siblings. Included are 139 ABO identical, 32 ABO minor mismatched, 34 major mismatched and 13 bi-directionally mismatched pairs. The statistical evaluation of standard parameters used to monitor the post-transplant period gave a proof that in neither group of patients with an ABO incompatible donor the recovery and success rate of transplantation, including the relapse incidence, risk of graft vs. host disease (GVHD) or overall survival, were significantly inferior. However, in all three cohorts of ABO mismatched patients, a delayed recovery of neutrophils was recorded as compared to the group receiving an ABO compatible graft. These finding leads us to the conclusion that the ABO compatibility is not a disadvantage in BMT, whereas the delayed recovery of neutrophils in patients having received an ABO mismatched graft is probably reflecting a transient humoral process leading to immune tolerance and graft accommodation.


Asunto(s)
Sistema del Grupo Sanguíneo ABO/inmunología , Incompatibilidad de Grupos Sanguíneos , Trasplante de Médula Ósea/inmunología , Adulto , Femenino , Supervivencia de Injerto/inmunología , Enfermedad Injerto contra Huésped/epidemiología , Humanos , Masculino , Neutrófilos/inmunología , Factores de Riesgo , Resultado del Tratamiento
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