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1.
Stud Health Technol Inform ; 264: 1504-1505, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438203

RESUMO

The study was done to validate the real time efficacy of a customised algorithm in detecting diabetic retinopathy (DR) among diabetic patients being examined at the vitreo retinal outpatient department (VR OPD) of a tertiary care hospital, Diabetic Retinopathy algorithm showed sensitivity of 79% and specificity of 57% which is an acceptable methodology to diagnose diabetic retinopathy and avoid unnecessary referrals.


Assuntos
Retinopatia Diabética , Algoritmos , Fundo de Olho , Humanos , Fotografação
2.
J Forensic Leg Med ; 67: 49-60, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31431262

RESUMO

For forensic clinicians and pathologists, photography of bodily regions, injuries and skin lesions present a number of technical challenges including proper framing, avoidance of distortion, choice of background and inclusion of a properly orientated scale. Photography of internal organs at autopsy presents further difficulties with regard to correct exposure, light reflections and limited depth of field. Situations commonly arise in clinical forensic and autopsy practice which require photographic documentation but which may not warrant calling upon the clinical photographer or police Scenes of Crime Officer. This article provides a brief explanation of various technical considerations which will allow forensic practitioners and technicians to take their own high quality external and internal photographs. Technical aspects discussed include aperture, shutter speed, ISO, depth of field, camera shake, and use of flash, scales, focal planes and backgrounds. The possible pitfalls encountered in several common photographic situations are illustrated and discussed, together with suggested workarounds and camera settings. Whilst the photographic examples presented here mostly relate to autopsy practice, the general principles and technical discussion also apply to wider clinical forensic photography practice.


Assuntos
Fotografação/métodos , Autopsia , Medicina Legal , Humanos , Iluminação , Fotografação/instrumentação
3.
Am J Orthod Dentofacial Orthop ; 155(6): 812-818, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31153501

RESUMO

OBJECTIVE: This study aimed to determine orthodontists' and layperson's perceptions about facial esthetics in a long face pattern sample. METHODS: The sample consisted of 64 frontal photographs of white Brazilian middle school students (9-15 years old), diagnosed as long faced through morphologic evaluation and confirmed by the facial index. A Likert-type scale was used to determine orthodontists' (22) and laypeople's (22) perceptions about facial esthetics. Chi-square and proportions tests were used for comparison between the examiners regarding the classification in each degree of esthetics, adopting a significance level of 5%. RESULTS: For orthodontists and laypeople, most of the subjects were considered to have acceptable appearance: 36.4% and 40.3%, respectively. Subjects whose appearance was classified as unpleasant constituted one-third of the sample: for orthodontists, 7.8% very unpleasant and 22.9% unpleasant, and 6.7% and 22.2%, respectively, for laypeople. The facial structures most cited as responsible for unpleasantness were the lack of lip sealing followed by incisor exposition. The increase of the lower third of the face for orthodontists and eyes for laypeople were the third most cited unpleasant characteristics. CONCLUSIONS: For the evaluators, two-thirds of the long face sample were considered to have an acceptable, pleasant, or very pleasant appearance. Laypeople's opinions aligned with the orthodontists', that one-third of long-face patients were considered to have an unpleasant appearance.


Assuntos
Estética , Face/anatomia & histologia , Adolescente , Brasil , Criança , Feminino , Humanos , Masculino , Fotografação , Sorriso
4.
N Z Vet J ; 67(5): 264-269, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31234719

RESUMO

Aims: To investigate the effect of the transverse arytenoid ligament (TAL) on abduction of the arytenoid cartilage when performing laryngoplasty. Methods: Modified prosthetic laryngoplasty was performed on right and left sides of 13 cadaver larynges. Increasing force was sequentially applied to the left arytenoid cartilage at 3 N intervals from 0-24 N, when the force on the right arytenoid cartilage was either 0 or 24 N, before and after TAL transection. Digital photographs of the rostral aspect of the larynx were used to determine the left arytenoid abduction angles for these given force combinations and results compared before and after TAL transection. Longitudinal and transverse sections of the TAL from seven other equine larynges were also examined histologically. Results: Increasing force on the left arytenoid cartilage from 0-24 N produced a progressive increase in the angle of the left arytenoid cartilage (p < 0.001) and increasing force on the right arytenoid cartilage from 0-24 N reduced the angle of the left arytenoid cartilage (p < 0.001). Following transection of the TAL the mean angle of the left arytenoid increased from 36.7 (95% CI = 30.5-42.8)° to 38.4 (95% CI = 32.3-44.5)°. Histological examination showed that the TAL was not a discrete ligament between the arytenoid cartilages but was formed by the convergence of the ligament and the left and right arytenoideus transversus muscles. Conclusions: Transection of the TAL in ex vivo equine larynges enabled greater abduction of the left arytenoid cartilage for a given force. These results indicate that TAL transection in conjunction with prosthetic laryngoplasty may have value, but the efficacy and safety of TAL transection under load in vivo, and in horses clinically affected with recurrent laryngeal neuropathy must be evaluated. Abbreviations: Fmax: Force needed to maximally abduct the left or right arytenoid; TAL: Transverse arytenoid ligament.


Assuntos
Cartilagem Aritenoide/fisiologia , Cavalos/fisiologia , Laringe/fisiologia , Ligamentos/fisiologia , Animais , Cartilagem Aritenoide/anatomia & histologia , Fenômenos Biomecânicos , Cadáver , Doenças dos Cavalos/cirurgia , Traumatismos do Nervo Laríngeo/cirurgia , Traumatismos do Nervo Laríngeo/veterinária , Laringoplastia/métodos , Laringoplastia/veterinária , Laringe/anatomia & histologia , Ligamentos/anatomia & histologia , Fotografação
5.
Forensic Sci Int ; 301: e1-e7, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31176532

RESUMO

Child pornography on the internet is one of the crimes with highest increasing incidence worldwide. In this specific type of crime, the victim's age has important legal implications. To overcome the lack of scientifically established protocols, European researchers explored and proposed a set of facial proportions obtained from images to estimate age. Within a validation scope, the present study aimed to test the applicability of morphological proportions from frontal photographs of the face to estimate age in a Brazilian population. Standardized frontal view photographs from 800 Brazilians (400 females and 400 males) homogeneously distributed in 4 age groups (6, 10, 14 and 18 years ± 30 days) were randomly selected from a Civilian Database of the Brazilian Federal Police. The selected images were analyzed with the aid of cephalometric landmarks. After landmarking the photographs, eighteen metric relations pre-established by Cattaneo et al. (C. Cattaneo, Z. Obertová, M. Ratnayake, L. Marasciuolo, J. Tutkuviene, P. Poppa, D. Gibelli, P. Gabriel, S. Ritz-Timme, Can facial proportions taken from images be of use for ageing in cases of suspected child pornography? A pilot study, Int. J. Leg. Med. 126 2012 139-144) were assessed and analyzed through parametric statistical tests and discriminant analysis. Two indexes had a moderate correlation with age, while ten had a weak correlation and six were not correlated with age. Eleven indexes were statistically different between sexes (p < 0.05). The discriminant analysis showed that 49.6% of the pooled sample was correctly classified into the respective age group. This percentage increased when each sex was analyzed separately: 50.2% for females and 53.5% for males. The set of facial proportions from frontal images proposed by Cattaneo et al. (2012) is related to facial development. As expected, the discriminant power of this approach did not reach optimal effectiveness in the Brazilian sample. In practice, this age estimation method must be adapted for more reliable application in Brazilians.


Assuntos
Envelhecimento/fisiologia , Face/anatomia & histologia , Desenvolvimento Maxilofacial/fisiologia , Fotografação , Adolescente , Pontos de Referência Anatômicos , Brasil , Cefalometria , Criança , Bem-Estar da Criança/legislação & jurisprudência , Crime , Análise Discriminante , Literatura Erótica , Feminino , Antropologia Forense , Humanos , Masculino
6.
Naturwissenschaften ; 106(7-8): 40, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31250116

RESUMO

Tandem oviposition, where males guide females in contact, requires quite a substantial muscle activity from males and, therefore, stronger heat production within the male thorax compared to the female thorax. In the present study, an infrared camera equipped with a macrolens was applied in the field, in order to estimate temperature in different body regions of male and female dragonflies Sympetrum vulgatum laying eggs in tandems. In both sexes, the thorax was considerably warmer than other body parts. The male thorax was on average 3-4 °C warmer than that of the female. These observations support previous data that Sympetrum males have a stronger muscular activity and heat production in tandem during the egg-laying process compared to females. The data provide additional evidence that this kind of contact guarding behavior during oviposition is rather costly for males. The tip of the male abdomen was much warmer than its own abdomen in the middle region. This result might be explained by possible heat transfer from the female head to the male abdomen through the contact between male abdominal appendages and the female head. An alternative explanation might be strong activity of the muscles controlling male anal appendages. Finally, this study also demonstrated a strong potential of IR cameras in field studies of dragonfly behavioral physiology.


Assuntos
Temperatura Corporal , Temperatura Alta , Odonatos/fisiologia , Oviposição/fisiologia , Animais , Técnicas Biossensoriais/instrumentação , Feminino , Raios Infravermelhos , Masculino , Fotografação/instrumentação
7.
Environ Monit Assess ; 191(6): 355, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31069552

RESUMO

We estimated canopy structure and transmitted radiation using hemispherical photography in four monitoring years (2008-2010, 2016) following the 2008 huge ice storm in a subtropical forest in south China, so as to assess changes in canopy biophysical parameters during forest recovery from natural disturbance. Significant decrease in canopy openness (CO), transmitted direct radiation (TransDir), and transmitted diffuse radiation (TransDif), as well as significant increase in leaf area index (LAI), were found in the disturbed forest stand in the subsequent years following the ice storm, indicating rapid canopy recovery. In contrast, these biophysical parameters of the undisturbed forest stand were quite stable during the monitoring years. The strength of relationships between CO and other canopy biophysical parameters decreased in the disturbed stand along the monitoring years. The disturbed stand had common slopes for the CO-TransDir and CO-TransDif models in the first two monitoring years, but different slopes for the CO-LAI model between the first and the subsequent monitoring years, while the undisturbed stand had common slopes for all the regression models in the first three monitoring years following the huge ice storm. These results showed that stronger correlations of LAI or TransDir with CO were characteristic of less complex canopies, such as those damaged by disturbance; the sensitivity of transmitted radiation in response to CO decreased with canopy recovery. Our findings demonstrated that forests with different canopy structure varied in biophysical parameters, which can be quantified by hemispherical photography.


Assuntos
Monitoramento Ambiental/métodos , Florestas , Gelo , China , Fotografação , Folhas de Planta , Árvores
8.
Forensic Sci Int ; 299: 239.e1-239.e9, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31053243

RESUMO

OBJECTIVES: The aim of the present study was to use Fourier analysis to quantify and study age-related changes in midsagittal facial profile. MATERIALS AND METHODS: Midsagittal facial profiles were extracted as lists of x and y coordinates from 125 pairs of 3D facial scans captured at an average of 10.5 years apart for adult Japanese males aged 23-52 years. These were categorized into three 10-year-long age groups. Files of x and y coordinates underwent Fourier analysis at 30 harmonic levels. Paired t-tests were used to determine statistical significance of differences across corresponding harmonic coefficients. Mean harmonic coefficients were used to construct mean pre and post ageing profiles for each age group for qualitative comparisons. RESULTS: Full detail of facial profile was described by the first 20 harmonics. With increasing age, there was a trend of longitudinal changes involving more midsagittal shape features with increased magnitudes. However, all changes were lower than 1 mm. CONCLUSIONS: Fourier analysis is a useful morphometric approach to quantify age-related midsagittal facial changes. The small variations in the study groups prompt for testing Fourier analysis on the elderly and on other parasagittal and transverse facial features.


Assuntos
Envelhecimento , Análise de Fourier , Desenvolvimento Maxilofacial , Adulto , Grupo com Ancestrais do Continente Asiático , Ciências Forenses , Humanos , Imagem Tridimensional , Japão , Estudos Longitudinais , Pessoa de Meia-Idade , Fotografação , Reprodutibilidade dos Testes , Adulto Jovem
9.
Forensic Sci Int ; 300: 6-12, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31059949

RESUMO

No human face is like another, not even in monozygotic twins, which makes the face one of the most individualizing characteristic. It is for this reason that the human face is commonly used for identification purposes and police officers take portrait photographs of arrested persons, so-called mug shots. The disadvantage of these 2D mug shots is that the perspective, in which they are taken (usually frontal and lateral-right, left or both), cannot be changed after acquisition, thus limiting a potential comparison between a mug shot and surveillance footage or other visual recordings. Documenting a face in 3D would reduce this problem as it allows adjusting the perspective of the face for image comparisons depending on the needs of the investigator. We have developed a 3D mug shot system containing 26 digital single-lens reflex cameras arranged semi-circularly in a 200° arc with a 1.46 m radius around a height-adjustable chair. We generated photogrammetric models of a test person's face captured by the mug shot system using three different focal lengths settings as well as 3D models of the same face with GOM Atos Triple Scan and Artec Space Spider. The 3D models were then analysed regarding the visibility of detailed morphological features in different regions of the face compared to 2D mug shots. Our results showed that our 3D mug shot system with its photogrammetric documentation generates 3D models with comparable surface quality to Artec-generated models, or even better quality, compared to GOM-generated models. The results of the morphological assessment were affected by the focal length and availability of texture information. In conclusion, the 3D mug shot system is a fast and efficient tool to generate 3D models of the face and may be used in addition to 2D photographs for the purpose of visual forensic identification based on images.


Assuntos
Face/anatomia & histologia , Imagem Tridimensional/métodos , Fotogrametria/métodos , Simulação por Computador , Ciências Forenses , Humanos , Fotografação , Software
10.
Ophthalmic Res ; 62(2): 61-67, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31067550

RESUMO

PURPOSE: Single-field non-mydriatic fundus photography (NMFP) has been used to detect diabetic retinopathy (DR) in many studies; however, its value in a general clinical setting has not been established. Here we performed a meta-analysis to evaluate its diagnostic effectiveness. METHOD: We systematically searched PubMed, EMBASE, and Cochrane databases for candidate studies published through May 19, 2018. A random-effect model was used to calculate the diagnostic indicators including the sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), area under the curve (AUC), and 95% confidence intervals. RESULTS: Ten prospective studies were ultimately included. The pooled sensitivity, specificity, PLR, NLR, and DOR were 0.68, 0.94, 11.2, 0.34 and 33, respectively. The AUC was 0.88. Subgroup analysis showed that single-field NMFP had a respective sensitivity and specificity of 0.73 and 0.91 when compared to standard 7-field mydriatic stereoscopic photography (7SF), and 0.54 and 0.98 when compared to slit-lamp biomicroscopy as reference standard. CONCLUSIONS: Single-field NMFP is inadequate to detect DR. Additionally, it showed higher sensitivity and lower specificity when 7SF was used as reference standard, as compared to slit-lamp biomicroscopy, suggesting that different reference standards used in DR screening might have affected the diagnostic results.


Assuntos
Retinopatia Diabética/diagnóstico por imagem , Técnicas de Diagnóstico Oftalmológico , Programas de Rastreamento/métodos , Fotografação/métodos , Área Sob a Curva , Humanos , Razão de Chances , Sensibilidade e Especificidade
11.
Acta Psychol (Amst) ; 197: 23-31, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31077995

RESUMO

Aerial photographs depict objects from an overhead position, which gives them several unusual visual characteristics that are challenging for viewers to perceive and memorize. However, even for untrained viewers, aerial photographs are still meaningful and rich with contextual information. Such visual stimulus properties are considered appropriate and important when testing for expertise effects in visual recognition memory. The current experiment investigated memory recognition in expert image analysts and untrained viewers using two types of aerial photographs. The experts were better than untrained viewers at recognizing both vertical aerial photographs, which is the domain of their expertise, and oblique aerial photographs. Thus, one notable finding is that the superior memory performance of experts is not limited to a domain of expertise but extends to a broader category of large-scale landscape scenes. Furthermore, the experts' recognition accuracy remained relatively stable throughout the experimental conditions, illustrating the ability to use semantic information over strictly visual information in memory processes.


Assuntos
Memória/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa/métodos , Fotografação/métodos , Competência Profissional , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
Neural Netw ; 116: 150-165, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31063925

RESUMO

This article presents a steganographic method StegoNN based on neural networks. The method is able to identify a photomontage from presented signed images. Unlike other academic approaches using neural networks primarily as classifiers, the StegoNN method uses the characteristics of neural networks to create suitable attributes which are then necessary for subsequent detection of modified photographs. This also results in a fact that if an image is signed by this technique, the detection of modifications does not need any external data (database of non-modified originals) and the quality of the signature in various parts of the image also serves to identify modified (corrupted) parts of the image. The experimental study was performed on photographs from CoMoFoD Database and its results were compared with other approaches using this database based on standard metrics. The performed study showed the ability of the StegoNN method to detect corrupted parts of an image and to mark places which have been most probably image-manipulated. The usage of this method is suitable for reportage photography, but in general, for all cases where verification (provability) of authenticity and veracity of the presented image are required.


Assuntos
Redes Neurais (Computação) , Reconhecimento Automatizado de Padrão/métodos , Fotografação/métodos , Bases de Dados Factuais/normas , Humanos , Reconhecimento Automatizado de Padrão/normas , Fotografação/normas , Reprodutibilidade dos Testes
13.
Appl Opt ; 58(13): 3467-3480, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31044844

RESUMO

This study was carried out to evaluate a method used to measure three-dimensional (3D) cognitive fatigue based on the pupillary response. This technique was designed to overcome measurement burdens by using non-contact methods. The pupillary response is related to cognitive function by a neural pathway and may be an indicator of 3D cognitive fatigue. Twenty-six undergraduate students (including 14 women) watched both 2D and 3D versions of a video for 70 min. The participants experienced visual fatigue after viewing the 3D content. Measures such as subjective rating, response time, event-related potential latency, heartbeat-evoked potential (HEP) alpha power, and task-evoked pupillary response (TEPR) latency were significantly different. Multitrait-multimethod matrix analysis indicated that HEP and TEPR latency measures had stronger reliability and higher correlations with 3D cognitive fatigue than other measures. TEPR latency may be useful for quantitatively determining 3D visual fatigue, as it can be easily used to evaluate 3D visual fatigue using a non-contact method without measuring burden.


Assuntos
Astenopia/diagnóstico , Imagem Tridimensional/métodos , Raios Infravermelhos , Fotografação/instrumentação , Pupila/fisiologia , Adulto , Astenopia/fisiopatologia , Cognição , Eletrocardiografia , Potenciais Evocados/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Adulto Jovem
14.
Appl Opt ; 58(13): D98-D104, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31044871

RESUMO

The Florida Everglades is infested with Burmese pythons caused by the release of exotic pets in the 1980s. The current estimates are between 30,000 and 300,000 pythons, where the result is a severe decline in Everglade mammals: 90% reductions in raccoon, opossum, bobcats, and foxes. The marsh rabbits are completely gone. The population of the pythons is rapidly increasing exponentially with 20-50 eggs per snake with a life span of up to 20 years. Pythons have been captured in the Everglades with lengths of nearly 6 m. Researchers in the state of Florida are concerned that these pythons are (1) permanently damaging the Everglades, (2) migrating further north into populated areas of Florida, and (3) endangering wildlife, pets, and eventually, people. There have been a number of sensing efforts attempted in the large-area detection of pythons, where limited success has been achieved. For example, infrared sensors have been applied to the problem, but the pythons are cold-blooded, so the infrared bands do not work well. Imec has leveraged its expertise and infrastructure in semiconductor processing to produce highly compact, higher performance, and relatively cheaper hyperspectral image sensors and camera systems. In this work, Imec teamed with the University of Florida and Extended Reality Systems to obtain hyperspectral reflectivity measurements of Burmese pythons along with natural Florida background foliage to determine bands or band combinations that may be exploited in the large-area detection of pythons. The bands investigated are the visible-near infrared (or VisNIR) and the shortwave infrared (SWIR) bands. The results show that there are enough differences in the data collection such that a single band, inexpensive VisNIR band camera may provide reasonable results and a two-band, VisNIR/SWIR combination may provide higher performance results. In this paper, we provide the VisNIR results.


Assuntos
Boidae/fisiologia , Ecossistema , Fotografação/instrumentação , Fenômenos Fisiológicos da Pele , Imagem Corporal Total/métodos , Animais , Meio Ambiente , Florida , Óptica e Fotônica
15.
Waste Manag ; 88: 337-346, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31079647

RESUMO

In an attempt to select an efficient recycling process for waste electrical and electronic equipment based on the value of individual products, we are engaged in the development of an automatic object-recognition system for discarded equipment. As part of this initiative, we developed a new object-recognition algorithm that uses the information from the labels on the bottoms of digital cameras discarded in Japan, which have a relatively high value. In addition, we created a program that can continuously process multiple two-dimensional digital images of the bottoms of the discarded cameras. The algorithm developed consists of the following: 1. Identifying the manufacturer using template matching with the manufacturer's logo on the label as a template image; 2. reading the model name located close to the logo using optical character recognition (OCR) processing; and 3. extracting the model-name candidates via a similarity calculation between the result of the OCR and the model-name list. After analyzing the information on the label of the discarded cameras, we carried out an object-recognition test using the images captured inside a photography box. The results demonstrated that on average, 48% of the total number of template images was necessary to identify all the manufacturers. This value varies from manufacturer to manufacturer; however, the template image with the "highest versatility" correctly matched 42% of the models of a certain manufacturer. The model-name identification for each manufacturer was successful 92% of the time on average, which indicated the effectiveness of this algorithm and emphasized the necessity of extracting the model-name candidates from the OCR result. Finally, assuming that a continuous process will be feasible in the future, a test was carried out using the photographed images of the discarded cameras moving on a conveyor belt at a speed of 0.5 m/s. The results demonstrated that the percentage of the number of template images required to identify the manufacturer was almost identical to that for static images. Notwithstanding the limitations of the image resolution (58% lower than that of the still images), the model-name identification rate was 81%.


Assuntos
Algoritmos , Reciclagem , Japão , Fotografação
17.
Cornea ; 38(7): 918-920, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30969261

RESUMO

PURPOSE: To describe a case of bilateral multifocal stromal crystalline keratopathy in the setting of relapsing polychondritis (RP). METHODS: Case report. RESULTS: We describe a 31-year-old woman who presented with ocular inflammation, bilateral auricular chondritis, and nasal chondritis, meeting the clinical criteria of RP. We illustrate her auricular cartilaginous abnormalities, saddle nose deformity, scleritis, and discrete mid-stromal opacities in both corneas that extend through the central cornea. Uniquely, her opacities feature a marked crystalline component as demonstrated on photography, anterior segment optical coherence tomography, and confocal microscopy. CONCLUSION: A central keratopathy is not typically reported in patients with RP. In this case report, we describe a unique diffuse bilateral nummular mid-stromal crystalline keratitis that extends into the central cornea and further define it using multimodal imaging.


Assuntos
Técnicas de Diagnóstico Oftalmológico , Policondrite Recidivante/diagnóstico por imagem , Adulto , Cristalinas/análise , Feminino , Humanos , Microscopia Confocal , Imagem Multimodal , Fotografação , Tomografia de Coerência Óptica
18.
Nat Protoc ; 14(5): 1455-1488, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30953041

RESUMO

Sleep is nearly universal among animals, yet remains poorly understood. Recent work has leveraged simple model organisms, such as Caenorhabditis elegans and Drosophila melanogaster larvae, to investigate the genetic and neural bases of sleep. However, manual methods of recording sleep behavior in these systems are labor intensive and low in throughput. To address these limitations, we developed methods for quantitative imaging of individual animals cultivated in custom microfabricated multiwell substrates, and used them to elucidate molecular mechanisms underlying sleep. Here, we describe the steps necessary to design, produce, and image these plates, as well as analyze the resulting behavioral data. We also describe approaches for experimentally manipulating sleep. Following these procedures, after ~2 h of experimental preparation, we are able to simultaneously image 24 C. elegans from the second larval stage to adult stages or 20 Drosophila larvae during the second instar life stage at a spatial resolution of 10 or 27 µm, respectively. Although this system has been optimized to measure activity and quiescence in Caenorhabditis larvae and adults and in Drosophila larvae, it can also be used to assess other behaviors over short or long periods. Moreover, with minor modifications, it can be adapted for the behavioral monitoring of a wide range of small animals.


Assuntos
Caenorhabditis elegans/fisiologia , Drosophila melanogaster/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Larva/fisiologia , Sono/fisiologia , Animais , Comportamento Animal/fisiologia , Microscopia , Fotografação
20.
BMC Ophthalmol ; 19(1): 89, 2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30961576

RESUMO

BACKGROUND: The evidence on diagnostic test accuracy (DTA) of diabetic retinopathy (DR) screening utilising photographic studies by non-ophthalmologist personnel in low and middle-income country (LMIC) settings is scarce. We aimed to assess DTA of DR screening using a nonmydriatic hand-held digital camera by trained general physicians in a non-ophthalmic setting. METHODS: This study is a validation of a screening intervention. We selected 700 people with diabetes (PwDM) > 18 years of age, not previously screened or treated for DR, presenting at a tertiary medical clinic in Sri Lanka. Two-field retinal imaging was used to capture fundus images before and after pupil dilatation, using a hand-held non-mydriatic (Visuscout 100®-Germany) digital retinal camera. The images were captured and graded by two trained, masked independent physician graders. The DTA of different levels of DR was assessed comparing physician's grading with a retinologist's clinical examination by mydriatic bio-microscopy, according to a locally adopted guideline. RESULTS: Seven hundred eligible PwDM were screened by physician graders. The mean age of participants was 60.8 years (SD ±10.08) and mean duration of DM was 9.9 years (SD ±8.09). Ungradable image proportion in non-mydriatic imaging was 43.4% (either eye-31.3%, both eyes 12.1%). This decreased to 12.8% (either eye-11.6%, both eyes-1.2%) following pupil dilatation. In comparison to detection of any level of DR, a referable level DR (moderate non-proliferative DR and levels above) showed a higher level of DTA. The sensitivity of the defined referable DR was 88.7% (95% CI 81.7-93.8%) for grader 1 (positive predictive value [PPV] 59.1%) and 92.5% (95% CI 86.4-96.5%) for grader 2 (PPV 68%), using mydriatic imaging, after including ungradable images as screen positives. The specificity was 94.9% (95% CI 93.6-96.0%) for grader 1 (negative predictive value [NPV] 99%) and 96.4% (95% CI 95.3-97.3%) for grader 2 (NPV 99.4%). CONCLUSIONS: The Physicians grading of images from a digital hand-held non-mydriatic camera at a medical clinic, with dilatation of pupil of those who have ungradable images, provides a valid modality to identify referable level of DR. This could be a feasible alternative modality to the existing opportunistic screening to improve the access and coverage. TRIAL REGISTRATION: Current Controlled Trials ISRCTN47559703 . Date of Registration 18th March 2019, Retrospectively registered.


Assuntos
Retinopatia Diabética/diagnóstico , Processamento de Imagem Assistida por Computador/métodos , Fotografação/instrumentação , Médicos , Retina/diagnóstico por imagem , Centros de Atenção Terciária , Seleção Visual/instrumentação , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Midriáticos , Estudos Prospectivos , Reprodutibilidade dos Testes
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