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1.
PLoS One ; 15(5): e0232583, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32392215

RESUMEN

A modern color filter array (CFA) output is rendered into the final output image using a demosaicing algorithm. During this process, the rendered image is affected by optical and carrier cross talk of the CFA pattern and demosaicing algorithm. Although many CFA patterns have been proposed thus far, an image-quality (IQ) evaluation system capable of comprehensively evaluating the IQ of each CFA pattern has yet to be developed, although IQ evaluation items using local characteristics or specific domain have been created. Hence, we present an IQ metric system to evaluate the IQ performance of CFA patterns. The proposed CFA evaluation system includes proposed metrics such as the moiré robustness using the experimentally determined moiré starting point (MSP) and achromatic reproduction (AR) error, as well as existing metrics such as color accuracy using CIELAB, a color reproduction error using spatial CIELAB, structural information using the structure similarity, the image contrast based on MTF50, structural and color distortion using the mean deviation similarity index (MDSI), and perceptual similarity using Haar wavelet-based perceptual similarity index (HaarPSI). Through our experiment, we confirmed that the proposed CFA evaluation system can assess the IQ for an existing CFA. Moreover, the proposed system can be used to design or evaluate new CFAs by automatically checking the individual performance for the metrics used.


Asunto(s)
Algoritmos , Aumento de la Imagen , Color , Aumento de la Imagen/instrumentación , Aumento de la Imagen/métodos , Sistema Métrico , Fotograbar/instrumentación , Fotograbar/métodos
3.
PLoS One ; 15(3): e0229538, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32187183

RESUMEN

Participation, defined as 'involvement in life situations' according to the World Health Organisation, is a well-recognized concept and critical indicator of quality of life. In addition it has become an important outcome measure in child rehabilitation. However, little is known about the level of participation of young children with Developmental Disabilities. The aim of this study was to capture their subjective experiences of participation. An adapted informed consent based on a comic strip was used to get the children's assent. A Photo Elicitation study was used, in which photographs were taken by the children when they were involved in meaningful activities. The photographs were then used to facilitate communication with the children and to initiate in depth-interviews. Forty-seven interviews with 16 children between five and nine years were conducted based on their photographs. This method generated rich data, confirming that young children with Developmental Disabilities were able to inform us accurately on their experiences of participation. Data was analysed by means of an inductive thematic analysis. Results showed that children perceived their participation as satisfying when they can play, learn and join in family gatherings resulting in feelings of inclusion, recognition and belonging. When there are-on occasions-moments that their participation was obstructed, the children used two strategies to resolve it. Or they walked away from it and choose not to participate, or when autonomously motivated for the activity, they relied primarily on their context (i.e. mothers) as enabling their participation. Related to the data, children discussed themes related to their person, activities, connections and mediators between those themes. These themes fit well within earlier and current research on the subject of participation.


Asunto(s)
Discapacidades del Desarrollo/psicología , Entrevista Psicológica/métodos , Participación Social/psicología , Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Trastorno del Espectro Autista/fisiopatología , Niño , Preescolar , Comunicación , Discapacidades del Desarrollo/fisiopatología , Emociones/fisiología , Familia , Femenino , Humanos , Masculino , Motivación/fisiología , Padres , Fotograbar/métodos , Investigación Cualitativa , Calidad de Vida , Percepción Visual/fisiología
4.
Plast Reconstr Surg ; 145(4): 1079-1086, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32221238

RESUMEN

Advances in computer science and photography not only are pervasive but are also quantifiably influencing the practice of medicine. Recent progress in both software and hardware technology has translated into the design of advanced artificial neural networks: computer frameworks that can be thought of as algorithms modeled on the human brain. In practice, these networks have computational functions, including the autonomous generation of novel images and videos, frequently referred to as "deepfakes." The technological advances that have resulted in deepfakes are readily applicable to facets of plastic surgery, posing both benefits and harms to patients, providers, and future research. As a specialty, plastic surgery should recognize these concepts, appropriately discuss them, and take steps to prevent nefarious uses. The aim of this article is to highlight these emerging technologies and discuss their potential relevance to plastic surgery.


Asunto(s)
Aprendizaje Automático/tendencias , Fotograbar/métodos , Procedimientos Quirúrgicos Reconstructivos/métodos , Grabación en Video/métodos , Predicción , Humanos , Fotograbar/tendencias , Procedimientos Quirúrgicos Reconstructivos/tendencias , Grabación en Video/tendencias
5.
Eur J Ophthalmol ; 30(1): 112-118, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30360660

RESUMEN

PURPOSE: The aim of this study is to assess the agreement between manual and automated gonioscopy for iridocorneal angle opening. METHODS: The research is a cross-sectional observational study. Manual and automated gonioscopy were performed to consecutive patients in a glaucoma clinic. Iridocorneal angle opening grading was performed according to Shaffer's classification. Automated gonioscopy was performed with NGS-1 automated gonioscope (NIDEK Co., Gamagori, Japan). The automated gonio-photos were graded by two independent observers. Agreement between automated and manual gonioscopy and also among raters was ascertained by Fleiss' kappa statistic and comparison of area under curve. RESULTS: In total, 88 eyes of 47 subjects were analysed. Mean age was 63 ± 10 years. Twenty eyes (22.7%) were excluded from grading due to poor quality images. Angle closure was detected in 23.4% with dynamic gonioscopy in comparison with 4.3% using automated image grading. The agreement for angle closure diagnosis between dynamic and automated gonioscopy was low (κ = 0.09 ± 0.10; p = 0.18). The area under curve for detecting eyes with angle closure showed poor accuracy between automated and manual methods (area under curve: 0.53 ± 0.05, 95% confidence interval: 0.44-0.62). There was modest inter-rater agreement for angle opening assessment of automated images with Fleiss' kappa of 0.17 (95% confidence interval: 0.035-0.238). CONCLUSION: Manual and automated gonioscopy showed only slight agreement for the assessment of iridocorneal angle opening status. Further improvements of the NGS-1 automated gonioscopy and technique are desired for widespread use in a real-life setting.


Asunto(s)
Cámara Anterior/diagnóstico por imagen , Glaucoma/diagnóstico , Gonioscopía/métodos , Fotograbar/métodos , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Adulto Joven
6.
Ecotoxicol Environ Saf ; 189: 110005, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31791729

RESUMEN

Frequent geological disasters based on a range of precipitating factors occur in areas with fragile geological environments, and the traditional artificial geological disaster survey method is often too dangerous to be carried out effectively. In order to achieve more efficient influence factors and refine the evaluation of micro-scale geological disaster susceptibility, this paper used UAV tilt photography and image processing technology to construct a 3D model of the geological environment. Geological disaster influence factors were extracted from a typical geological disaster area within Qingchuan County, Sichuan Province. A weighted certainty factor method and information model method were used to evaluate geological disaster susceptibility. The geological disaster susceptibility index of different characteristic variables was calculated using a certainty factors method, while factor weight was determined using an information model. The geological environment "potentiality parameter" for each grid unit, taken as the basis of geological disaster susceptibility zoning in the area, was calculated by coupling factor weight and CF value. Finally, the ROC test method was used to verify evaluation results of geological hazard susceptibility. This study found that: (1) UAV tilt photogrammetry data can be an effective method for geological disaster susceptibility evaluation. (2) The areas under the ROC curve calculated using the two methods were 66.20% and 81.71%, respectively, showing that accuracy of the weighted certainty factor method was higher than that of the information method.


Asunto(s)
Aeronaves , Desastres , Fotograbar/métodos , Tecnología de Sensores Remotos/métodos , China , Desastres/prevención & control , Humanos , Imagenología Tridimensional , Fotograbar/estadística & datos numéricos , Regresión Espacial
7.
J Sci Med Sport ; 23(1): 15-19, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31501022

RESUMEN

OBJECTIVES: Previous studies comparing shoes based on the amount of midsole cushioning have generally used shoes from multiple manufacturers, where factors outside of stack height may contribute to observed biomechanical differences in running mechanics between shoes. Therefore, the purpose of this study was to compare ground reaction forces and ankle kinematics during running between three shoes (maximal, traditional, and minimal) from the same manufacturer that only varied in stack height. DESIGN: Within-participant repeated measures METHODS: Twenty recreational runners ran overground in the laboratory in three shoe conditions (maximal, traditional, minimal) while three-dimensional kinematic and kinetic data were collected using a 3D motion capture system and two embedded force plates. Repeated measures ANOVAs (α=.05) compared biomechanical data between shoes. RESULTS: While the loading rate was significantly greater in the minimal shoe compared to the maximal shoe, no other differences were seen for the ground reaction force variables. Peak eversion was greater in the maximal and minimal shoe compared to the traditional shoe, while eversion duration and eversion at toe-off were greater in the maximal shoe. CONCLUSIONS: Previously cited differences in ground reaction force parameters between maximal and traditional footwear may be due to factors outside of midsole stack height. The eversion mechanics in the maximal shoes from this study may place runners at a greater risk of injury. Disagreement between previous studies indicates that more research on maximal running shoes is needed.


Asunto(s)
Carrera , Zapatos , Equipo Deportivo , Adulto , Fenómenos Biomecánicos , Diseño de Equipo , Femenino , Humanos , Masculino , Fotograbar/métodos
8.
J Sci Med Sport ; 23(1): 7-14, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31421988

RESUMEN

Velocity-based training (VBT) requires the monitoring of lift velocity plus the prescribed resistance weight. A validated and reliable device is needed to capture the velocity and power of several exercises. OBJECTIVES: The study objectives were to examine the validity and reliability of the Elite Form Training System® (EFTS) for measures of peak velocity (PV), average velocity (AV), peak power (PP), and average power (AP). DESIGN: Validity of the EFTS was assessed by comparing measurements simultaneously obtained via the Qualisys Track Manager software (C-motion, version 3.90.21, Gothenburg, Sweden) utilizing 6 motion capture cameras (Oqus 400, 240 Hz, Gothenburg, Sweden). METHODS: Six participants performed 6 resistance exercises in 2 sessions: power clean, dead lift, bench press, back squat, front squat, and jump squat. RESULTS: Simple Pearson correlations indicated the validity of the device (0.982, 0.971, 0.973, and 0.982 for PV, AV, PP, and AP respectively) and ranged from 0.868 to 0.998 for the 6 exercises. The test-retest reliability of the EFTS was shown by lack of significant change in the Pearson correlation (<0.3% for each variable) between the 2 sessions. The multiple count error rate was 2.0% and the missed count error rate was 2.1%. CONCLUSIONS: The validity and reliability of the EFTS were classified as excellent across all variables and exercises with only one exercise showing a slight influence by the velocity of the movement.


Asunto(s)
Fotograbar/instrumentación , Levantamiento de Peso/fisiología , Adulto , Humanos , Masculino , Fotograbar/métodos , Reproducibilidad de los Resultados , Programas Informáticos , Adulto Joven
9.
J Vis Exp ; (154)2019 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-31885385

RESUMEN

We describe a method to image dissolved oxygen (O2), in 2D at high spatial (< 50-100 µm) and temporal (< 10 s) resolution. The method employs O2 sensitive luminescent sensor foils (planar optodes) in combination with a specialized camera system for imaging luminescence lifetime in the frequency-domain. Planar optodes are prepared by dissolving the O2-sensitive indicator dye in a polymer and spreading the mixture on a solid support in a defined thickness via knife coating. After evaporation of the solvent, the planar optode is placed in close contact with the sample of interest - here demonstrated with the roots of the aquatic plant Littorella uniflora. The O2 concentration-dependent change in the luminescence lifetime of the indicator dye within the planar optode is imaged via the backside of the transparent carrier foil and aquarium wall using a special camera. This camera measures the luminescence lifetime (µs) via a shift in phase angle between a modulated excitation signal and emission signal. This method is superior to luminescence intensity imaging methods, as the signal is independent of the dye concentration or intensity of the excitation source, and solely relies on the luminescence decay time, which is an intrinsically referenced parameter. Consequently, an additional reference dye or other means of referencing are not needed. We demonstrate the use of the system for macroscopic O2 imaging of plant rhizospheres, but the camera system can also easily be coupled to a microscope.


Asunto(s)
Imagenología Tridimensional , Luminiscencia , Oxígeno/metabolismo , Fotograbar/métodos , Calibración , Plantaginaceae/fisiología , Rizosfera
10.
Artículo en Inglés | MEDLINE | ID: mdl-31861457

RESUMEN

To investigate the parameters of eye movement between ophthalmologists and optometrists while diagnosing digital fundus photographs, sixteen participants (eight ophthalmologists and eight optometrists) were recruited in this study. Every participant's eye movement during diagnosis of a randomized set of fundus photographs displayed on an eye tracker were recorded. Fixation metrics (duration, count and rate) and scan path patterns were extracted from the eye tracker. These parameters of eye movement and correct diagnosis score were compared between both groups. Correlation analyses between fixation metrics and correct diagnosis score were also performed. Although fixation metrics between ophthalmologists and optometrists were not statistically different (p > 0.05), these parameters were statistically different when compared between different area of interests. Both participant groups had a similar correct diagnosis score. No correlation was found between fixation metrics and correct diagnosis score between both groups, except for total fixation duration and ophthalmologists' diagnosis score of diabetic retinopathy photographs. The ophthalmologists' scan paths were simpler, with larger saccades, and were distributed at the middle region of the photographs. Conversely, optometrists' scan paths were extensive, with shorter saccades covering wider fundus areas, and were accumulated in some unrelated fundus areas. These findings indicated comparable efficiency and systematic visual search patterns between both the groups. Understanding visual search strategy could expedite the creation of a novel training routine for interpretation of ophthalmic diagnostic imaging.


Asunto(s)
Competencia Clínica/estadística & datos numéricos , Retinopatía Diabética/diagnóstico , Movimientos Oculares , Fondo de Ojo , Oftalmólogos/psicología , Optometristas/psicología , Fotograbar/métodos , Adulto , Humanos , Persona de Mediana Edad , Variaciones Dependientes del Observador , Oftalmólogos/normas , Optometristas/normas
11.
Forensic Sci Int ; 305: 109998, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31707237

RESUMEN

Bruising is an injury commonly observed within suspect cases of assault or abuse, yet how a blunt impact initiates bruising and influences its severity is not fully understood. Furthermore, the standard method of documenting a bruise with colour photography is known to have limitations which influence the already subjective analysis of a bruise. This research investigated bruising using a standardised blunt impact, delivered to 18 volunteers. The resulting bruise was imaged using colour, cross polarised (CP) and infrared photography. Timelines of the L*a*b* colour space were determined from both colour and CP images for up to 3 weeks. Overall, no single photographic technique out-performed the others, however CP did provide greater contrast than colour photography. L*a*b* colour space timelines were not attributable any physiological characteristics. Whilst impact force negatively correlated with BMI (R2 = 0.321), neither were associated with any measure of bruise appearance. Due to the inter-subject variability in the bruise response to a controlled infliction, none of the methods in the current study could be used to reliably predict the age of a bruise or the severity of force used in creating a bruise. A more comprehensive approach combining impact characteristics, tissue mechanics, enhanced localised physiological measures and improvements in quantifying bruise appearance is likely to be essential in removing subjectivity from their interpretation.


Asunto(s)
Contusiones/patología , Piel/patología , Adulto , Fenómenos Biomecánicos , Índice de Masa Corporal , Femenino , Medicina Legal/métodos , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Fotograbar/métodos , Piel/lesiones , Factores de Tiempo , Adulto Joven
12.
Ophthalmic Surg Lasers Imaging Retina ; 50(10): 639-648, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31671197

RESUMEN

Ultra-widefield fundus imaging (UWFI) is a relatively new technology capable of capturing 200° images of the retina. Since vision changes can be irreversible in diabetic retinopathy (DR), recognition of prognostic biomarkers in the peripheral retina may prove invaluable toward optimizing the management and reducing the societal burden of this blinding disease. Following a bibliographic review using Pubmed, OVID Medline, Embase, and the Cochrane Library, the current review systematically examined 13 studies that compared UWFI to conventional screening techniques such as seven standard field (7SF) Early Treatment In Diabetic Retinopathy Study (ETDRS) and non-mydriatic multifield fundus photography (NMFP), as well as their scientific level of evidence. Overall, UWFI had good agreement with 7SF ETDRS and NMFP, and moderate agreement with dilated fundus examination. Seven additional studies were examined that considered the significance of peripheral lesions found on UWFI. These studies demonstrated that UWFI captured additional DR pathology in the peripheral retina that may not be evident if evaluation is limited to the posterior pole and may be relevant to patient outcomes. Future directions include but are not limited to the potential of UWFI to track the progression of DR with treatment. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:639-648.].


Asunto(s)
Retinopatía Diabética/diagnóstico por imagen , Oftalmoscopía/métodos , Fotograbar/métodos , Progresión de la Enfermedad , Diagnóstico Precoz , Humanos
13.
Diabetes Res Clin Pract ; 157: 107840, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31733978

RESUMEN

AIMS: The purpose of this study is to assess the prevalence of diabetic retinopathy (DR) world-wide from articles published since 2015 where the assessment of the presence and severity of DR was based on retinal images. METHODS: A total of 4 databases were searched for the MESH terms diabetic retinopathy and prevalence. Of 112 publications 32 studies were included and individual data pooled for analysis. The presence of any DR or diabetic macular edema (DME) was recorded and severity as mild, moderate or severe non-proliferative DR (NPDR), proliferative DR (PDR) and DME and/or clinically significant macular edema (CSME). The level of severity of DR reported refer to persons with diabetes and not individual eyes. RESULTS: The global prevalence of DR and DME, for the period 2015 to 2019 were 27.0% for any DR comprising of 25.2%, NPDR, 1.4% PDR and 4.6% DME. The lowest prevalence was in Europe at 20.6% and South East Asia at 12.5% and highest in Africa at 33.8%, Middle East and North Africa 33.8%, and the Western Pacific region at 36.2%. CONCLUSIONS: This study illustrated difficulties in deriving a meaningful global prevalence rate for DR and DME due to the lack of uniformity in defining the study populations, methodological differences, retinal image capture and grading criteria. Therefore, international consensus is required using a minimal data set for future studies.


Asunto(s)
Retinopatía Diabética/epidemiología , Fotograbar/métodos , Femenino , Historia del Siglo XXI , Humanos , Masculino , Persona de Mediana Edad , Prevalencia
14.
BMC Ophthalmol ; 19(1): 231, 2019 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-31744471

RESUMEN

BACKGROUND: Conventional flash fundus cameras capture color images that are oversaturated in the red channel and washed out in the green and blue channels, resulting in a retinal picture that often looks flat and reddish. A white LED confocal device was recently introduced to provide a high-quality retinal image with enhanced color fidelity. In this study, we aimed to evaluate the color rendering properties of the white LED confocal system and compare them to those of a conventional flash fundus camera through chromaticity analysis. METHODS: A white LED confocal device (Eidon, Centervue, Padova, Italy) and a traditional flash fundus camera (TRC-NW8, Topcon Corporation, Tokyo, Japan) were used to capture fundus images. Color images were evaluated with respect to chromaticity. Analysis was performed according to the image color signature. The color signature of an image was defined as the distribution of its pixels in the rgb chromaticity space. The descriptors used for the analysis are the average and variability of the barycenter positions, the average of the variability and the number of unique colors (NUC) of all signatures. RESULTS: Two hundred thirty-three color photographs were acquired with each retinal camera. The images acquired by the confocal white LED device demonstrated an average barycenter position (rgb = [0.448, 0.328, 0.224]) closer to the center of the chromaticity space, while the conventional fundus camera provides images with a clear shift toward red at the expense of the blue and green channels (rgb = [0.574, 0.278, 0.148] (p < 0.001). The variability of the barycenter positions was higher in the white LED confocal system than in the conventional fundus camera. The average variability of the distributions was higher (0.003 ± 0.007, p < 0.001) in the Eidon images compared to the Topcon camera, indicating a greater richness of color. The NUC percentage was higher for the white LED confocal device than for the conventional flash fundus camera (0.071% versus 0.025%, p < 0.001). CONCLUSIONS: Eidon provides more-balanced color images, with a wider richness of color content, compared to a conventional flash fundus camera. The overall higher chromaticity of Eidon may provide benefits in terms of discriminative power and diagnostic accuracy.


Asunto(s)
Microscopía Confocal/métodos , Imagen Óptica/métodos , Fotograbar/métodos , Retina/diagnóstico por imagen , Color , Estudios Transversales , Humanos , Estudios Prospectivos
15.
Ophthalmic Surg Lasers Imaging Retina ; 50(11): e274-e277, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31755978

RESUMEN

BACKGROUND AND OBJECTIVE: This study examines the rate of adherence to recommended ophthalmology follow-up after primary care-based telemedicine diabetic retinopathy (DR) screening. PATIENTS AND METHODS: Retrospective observational study of 5,764 insured diabetic patients undergoing telemedicine DR screening between May 2015 and April 2017 in an urban primary care setting. Patients underwent non-mydriatic fundus photography for telemedicine DR screening. The main outcome measure was the "capture rate." RESULTS: Of the patients studied, 31.7% were found to have any retinal pathology, and 20% were found to have DR. In the 11.8% percent of patients with sight-threatening retinopathy who were recommended to have a retinal examination, the capture rate was 81.9%. CONCLUSION: The authors' study demonstrated higher capture rate than has been previously reported, indicating that telemedicine DR screening in an urban, insured population may be a useful method for triaging high-risk patients without losing patients to follow-up. [Ophthalmic Surg Lasers Imaging Retina. 2019;50: e274-e277.].


Asunto(s)
Retinopatía Diabética/diagnóstico , Técnicas de Diagnóstico Oftalmológico , Tamizaje Masivo/organización & administración , Telemedicina/métodos , Servicios Urbanos de Salud/organización & administración , Adulto , Femenino , Fondo de Ojo , Adhesión a Directriz/normas , Humanos , Masculino , Persona de Mediana Edad , Fotograbar/métodos , Estudios Retrospectivos
16.
BMC Ophthalmol ; 19(1): 229, 2019 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-31733642

RESUMEN

PURPOSE: To investigate the diagnostic accuracy of noninvasive multimodal imaging methods in diagnosing polypoidal choroidal vasculopathy (PCV) and distinguishing PCV from typical neovascular age-related macular degeneration (nvAMD). METHODS: Retrospective study. Imaging features of noninvasive multimodal imaging methods, including fundus photography (FP), B-scan optical coherence tomography (OCT), en face OCT, OCT angiography, and autofluorescence, of 103 eyes with PCV or typical nvAMD were reviewed. Diagnostic strategy was established based on imaging features and was validated in other 105 eyes with PCV or typical nvAMD. RESULTS: Features of subretinal orange nodule on FP, thumb-like PED on OCT, notched PED on OCT, bubble sign on OCT, and Bruch's membrane depression under serosanguinous PED on OCT were more common. When the diagnostic strategy of using at least 2 of 5 features was performed, there is 0.88 sensitivity and 0.92 specificity for diagnosing PCV. The results of the validation test further confirmed the diagnostic strategy with 0.94 sensitivity and 0.93 specificity. CONCLUSIONS: Noninvasive multimodal imaging, especially FP and B-scan OCT, provide high sensitivity and specificity for diagnosing PCV and distinguishing PCV from typical nvAMD, when at least 2 of 5 suggestive imaging features are present.


Asunto(s)
Enfermedades de la Coroides/diagnóstico , Técnicas de Diagnóstico Oftalmológico , Enfermedades Vasculares Periféricas/diagnóstico , Anciano , Anciano de 80 o más Años , Neovascularización Coroidal/diagnóstico , Diagnóstico Diferencial , Femenino , Angiografía con Fluoresceína/métodos , Humanos , Degeneración Macular/diagnóstico , Masculino , Persona de Mediana Edad , Imagen Multimodal , Fotograbar/métodos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Tomografía de Coherencia Óptica/métodos
17.
J Insect Sci ; 19(5)2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31587065

RESUMEN

The Asian cockroach, Blattella asahinai Mizukubo, has expanded its range throughout the southeastern United States since its introduction into Florida. Unlike its closest relative, the German cockroach, Blattella germanica (L.), B. asahinai lives outdoors and can fly. There is little information on the biology and development of B. asahinai, including the number of instars during nymphal development. To estimate the number of instars of B. asahinai, nymphs were photographed, sexed, and the lengths and widths of their pronota were measured digitally. The number of instars of B. asahinai was estimated using Gaussian mixture models with the pronotal data. The most probable model and its clusters were selected to assign individuals to an instar. Instars were also determined by counting the number of cercal annuli of nymphs. Both clustering and cercal annuli indicated that B. asahinai most frequently had six instars when reared at 30°C. Growth did not strictly follow the Brooks-Dyar Rule, because nymphs had different numbers of instars and different growth patterns. Although Gaussian mixture models are not efficient for field sampling experiments, digital measurements may provide a way to estimate instars with live specimens in development studies without handling the animals in a way that may alter growth.


Asunto(s)
Blattellidae/crecimiento & desarrollo , Animales , Blattellidae/anatomía & histología , Femenino , Masculino , Ninfa/anatomía & histología , Ninfa/crecimiento & desarrollo , Fotograbar/métodos
19.
PLoS One ; 14(9): e0221203, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31568494

RESUMEN

With the introduction of multi-camera systems in modern plant phenotyping new opportunities for combined multimodal image analysis emerge. Visible light (VIS), fluorescence (FLU) and near-infrared images enable scientists to study different plant traits based on optical appearance, biochemical composition and nutrition status. A straightforward analysis of high-throughput image data is hampered by a number of natural and technical factors including large variability of plant appearance, inhomogeneous illumination, shadows and reflections in the background regions. Consequently, automated segmentation of plant images represents a big challenge and often requires an extensive human-machine interaction. Combined analysis of different image modalities may enable automatisation of plant segmentation in "difficult" image modalities such as VIS images by utilising the results of segmentation of image modalities that exhibit higher contrast between plant and background, i.e. FLU images. For efficient segmentation and detection of diverse plant structures (i.e. leaf tips, flowers), image registration techniques based on feature point (FP) matching are of particular interest. However, finding reliable feature points and point pairs for differently structured plant species in multimodal images can be challenging. To address this task in a general manner, different feature point detectors should be considered. Here, a comparison of seven different feature point detectors for automated registration of VIS and FLU plant images is performed. Our experimental results show that straightforward image registration using FP detectors is prone to errors due to too large structural difference between FLU and VIS modalities. We show that structural image enhancement such as background filtering and edge image transformation significantly improves performance of FP algorithms. To overcome the limitations of single FP detectors, combination of different FP methods is suggested. We demonstrate application of our enhanced FP approach for automated registration of a large amount of FLU/VIS images of developing plant species acquired from high-throughput phenotyping experiments.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Plantas/anatomía & histología , Algoritmos , Clorofila/metabolismo , Fluorescencia , Humanos , Procesamiento de Imagen Asistido por Computador/estadística & datos numéricos , Iluminación , Fenotipo , Fotograbar/métodos , Desarrollo de la Planta , Hojas de la Planta/anatomía & histología , Hojas de la Planta/metabolismo , Plantas/metabolismo
20.
PLoS One ; 14(9): e0222025, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31536537

RESUMEN

PURPOSE: To provide a self-adaptive deep learning (DL) method to automatically detect the eye laterality based on fundus images. METHODS: A total of 18394 fundus images with real-world eye laterality labels were used for model development and internal validation. A separate dataset of 2000 fundus images with eye laterality labeled manually was used for external validation. A DL model was developed based on a fine-tuned Inception-V3 network with self-adaptive strategy. The area under receiver operator characteristic curve (AUC) with sensitivity and specificity and confusion matrix were applied to assess the model performance. The class activation map (CAM) was used for model visualization. RESULTS: In the external validation (N = 2000, 50% labeled as left eye), the AUC of the DL model for overall eye laterality detection was 0.995 (95% CI, 0.993-0.997) with an accuracy of 99.13%. Specifically for left eye detection, the sensitivity was 99.00% (95% CI, 98.11%-99.49%) and the specificity was 99.10% (95% CI, 98.23%-99.56%). Nineteen images were wrongly classified as compared to the human labels: 12 were due to human wrong labelling, while 7 were due to poor image quality. The CAM showed that the region of interest for eye laterality detection was mainly the optic disc and surrounding areas. CONCLUSION: We proposed a self-adaptive DL method with a high performance in detecting eye laterality based on fundus images. Results of our findings were based on real world labels and thus had practical significance in clinical settings.


Asunto(s)
Ojo/diagnóstico por imagen , Lateralidad Funcional , Fotograbar/métodos , Anciano , Algoritmos , Área Bajo la Curva , Aprendizaje Profundo , Técnicas de Diagnóstico Oftalmológico , Fondo de Ojo , Humanos , Persona de Mediana Edad , Fenómenos Fisiológicos Oculares , Sensibilidad y Especificidad
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