Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
1.
Knee Surg Sports Traumatol Arthrosc ; 32(6): 1434-1445, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38563648

RESUMO

PURPOSE: Although the Dejour classification is the primary classification system for evaluating trochlear dysplasia, concerns have been raised about its reliability owing to its qualitative criteria and challenges associated with obtaining accurate radiographs. This study aimed to quantify trochlear dysplasia using three-dimensional (3D) computed tomography (CT) reconstruction with novel parameters related to the transepicondylar axis (TEA). METHODS: Sixty patients were enrolled, including 20 with trochlear dysplasia and 40 healthy controls. The 3D CT model was generated using the Materialise Interactive Medical Image Control System software. The following six parameters were measured in eight consecutive planes at 15° intervals (planes 0-105): the distance from the TEA to the most cortical point of the lateral condyle ('LP-TEA', where LP stands for lateral peak), medial condyle ('MP-TEA', MP for medial peak) and deepest point of the trochlea ('TG-TEA', TG for trochlear groove). The distances from the medial epicondyle (MEC) to the corresponding TEA points were measured ('LP-MEC', 'MP-MEC' and 'TG-MEC'). RESULTS: In the dysplasia group, TG-TEA (planes 0, 15 and 30) and MP-MEC (planes 0, 15 and 30) were significantly greater than those in the control group (all p < 0.05 for planes of TG-TEA and MP-MEC). For type A dysplasia, LP-MEC (plane 0) was greater than that in the control group. For type B dysplasia, the MP-MEC (planes 0 and 15) and TG-TEA (planes 0 and 15) were greater than those of the control group. For type D dysplasia, MP-MEC (planes 0, 15 and 30) and TG-TEA (planes 0 and 15) were elevated. CONCLUSION: The 3D CT reconstruction analysis established a reproducible method for quantifying osseous trochlear morphology. Patients with trochlear dysplasia had a shallow TG and narrow medial trochlear width at tracking angles of 0°-30°. This finding corroborates the clinical manifestations of recurrent patellar instability that occur during early flexion. LEVEL OF EVIDENCE: Level III.


Assuntos
Imageamento Tridimensional , Tomografia Computadorizada por Raios X , Humanos , Feminino , Masculino , Adulto , Adulto Jovem , Adolescente , Fêmur/diagnóstico por imagem , Estudos de Casos e Controles , Reprodutibilidade dos Testes , Articulação do Joelho/diagnóstico por imagem
2.
Sensors (Basel) ; 21(3)2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33573308

RESUMO

Wireless sensor networks (WSN) are widely used to provide users with convenient services such as health-care, and smart home. To provide convenient services, sensor nodes in WSN environments collect and send the sensing data to the gateway. However, it can suffer from serious security issues because susceptible messages are exchanged through an insecure channel. Therefore, secure authentication protocols are necessary to prevent security flaws in WSN. In 2020, Moghadam et al. suggested an efficient authentication and key agreement scheme in WSN. Unfortunately, we discover that Moghadam et al.'s scheme cannot prevent insider and session-specific random number leakage attacks. We also prove that Moghadam et al.'s scheme does not ensure perfect forward secrecy. To prevent security vulnerabilities of Moghadam et al.'s scheme, we propose a secure and lightweight mutual authentication protocol for WSNs (WSN-SLAP). WSN-SLAP has the resistance from various security drawbacks, and provides perfect forward secrecy and mutual authentication. We prove the security of WSN-SLAP by using Burrows-Abadi-Needham (BAN) logic, Real-or-Random (ROR) model, and Automated Verification of Internet Security Protocols and Applications (AVISPA) simulation. In addition, we evaluate the performance of WSN-SLAP compared with existing related protocols. We demonstrate that WSN-SLAP is more secure and suitable than previous protocols for WSN environments.


Assuntos
Segurança Computacional , Confidencialidade , Simulação por Computador , Lógica
3.
Arthroscopy ; 35(6): 1713-1720, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31078358

RESUMO

PURPOSE: To evaluate whether the fibular position and lateral proximal tibial geometry affect the osteotomy configuration and lateral hinge fracture (LHF) during open wedge high tibial osteotomy (OWHTO). METHODS: From March 2014 to January 2016, patients who underwent OWHTO for isolated medial compartment osteoarthritis of the knee were retrospectively reviewed. To identify whether the fibular position and lateral proximal tibial geometry affect the osteotomy configuration, the fibular height, fibular anteroposterior position, lateral tibial condylar width, and lateral tibial condylar slope were evaluated on plain radiograph or computed tomography (CT). Thereafter, the correlation of these parameters with the thickness of the proximal fragment around the osteotomy end and LHFs was determined. RESULTS: A total of 123 OWHTOs including 30 LHFs (24.3%) were evaluated. High fibular head and small tibial condylar width and slope were related to thin thickness of the proximal tibial fragment, particularly on the posterior side (fibular height, P = .005; condylar width, P = .002; condylar slope, P = .01). The fibular height was shorter in the LHF group than in the non-LHF group on both plain radiography and CT (fibular height [plain radiography], 18.3 ± 1.6 vs 20.2 ± 2.1 mm; P < .001; fibular height [CT], 17.4 ± 1.1 vs 19.6 ± 2.0 mm; P < .001). The lateral tibial condylar width and slope were also smaller in the LHF group compared with the non-LHF group (tibial condylar width, 21.2 ± 4.9 vs 23.4 ± 4.5 mm; P = .023; tibial condylar slope, 37.7 ± 6.6 vs 41.3 ± 7.6 mm; P = .027). CONCLUSIONS: The fibular position and lateral proximal tibial geometry affect the osteotomy configuration and LHFs. A highly positioned fibula was related to a small lateral tibial condyle, which induced a thin proximal fragment. This finding was related to a higher risk of LHFs. Therefore, understanding the fibular height and lateral proximal tibial geometry may be helpful for the prediction of the osteotomy configuration and development of LHFs. LEVEL OF EVIDENCE: Level III, case-control study.


Assuntos
Fíbula/diagnóstico por imagem , Osteoartrite do Joelho/cirurgia , Osteotomia/efeitos adversos , Complicações Pós-Operatórias/etiologia , Tíbia/diagnóstico por imagem , Fraturas da Tíbia/etiologia , Adulto , Estudos de Casos e Controles , Feminino , Fixação Interna de Fraturas/métodos , Humanos , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/cirurgia , Próteses e Implantes , Radiografia , Reoperação , Estudos Retrospectivos , Fraturas da Tíbia/diagnóstico , Fraturas da Tíbia/cirurgia , Tomografia Computadorizada por Raios X/métodos
4.
BMC Gastroenterol ; 15: 128, 2015 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-26444007

RESUMO

BACKGROUND: Mucosal Schwann-cell hamartoma is a rare mesenchymal polyp that presents in the intestine. Despite lacking ganglion cells, it resembles a gastrointestinal ganglioneuroma. CASE PRESENTATION: We report a case of synchronous mucosal Schwann-cell hamartomas in a young male patient, who presented with a single discrete polyp in the mid-rectum and multiple polypoid mucosal lesions in the distal rectum. CONCLUSION: To the best of our knowledge, this is the first report of a case of multiple mucosal Schwann-cell hamartomas.


Assuntos
Hamartoma/patologia , Pólipos Intestinais/patologia , Doenças Retais/patologia , Células de Schwann , Humanos , Masculino , Adulto Jovem
5.
Small ; 8(14): 2203-12, 2129, 2012 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-22517593

RESUMO

A new platform technology is herein described with which to construct molecular logic gates by employing the hairpin-structured molecular beacon probe as a basic work unit. In this logic gate operation system, single-stranded DNA is used as the input to induce a conformational change in a molecular beacon probe through a sequence-specific interaction. The fluorescent signal resulting from the opening of the molecular beacon probe is then used as the output readout. Importantly, because the logic gates are based on DNA, thus permitting input/output homogeneity to be preserved, their wiring into multi-level circuits can be achieved by combining separately operated logic gates or by designing the DNA output of one gate as the input to the other. With this novel strategy, a complete set of two-input logic gates is successfully constructed at the molecular level, including OR, AND, XOR, INHIBIT, NOR, NAND, XNOR, and IMPLICATION. The logic gates developed herein can be reversibly operated to perform the set-reset function by applying an additional input or a removal strand. Together, these results introduce a new platform technology for logic gate operation that enables the higher-order circuits required for complex communication between various computational elements.


Assuntos
Técnicas Biossensoriais/métodos , DNA de Cadeia Simples/química , Sondas Moleculares/química , Sequência de Bases , Conformação de Ácido Nucleico , Oligonucleotídeos/química , Espectrometria de Fluorescência , Temperatura
6.
IEEE Trans Pattern Anal Mach Intell ; 44(1): 442-455, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32750815

RESUMO

We propose a novel and unified solution for user-guided video object segmentation tasks. In this work, we consider two scenarios of user-guided segmentation: semi-supervised and interactive segmentation. Due to the nature of the problem, available cues - video frame(s) with object masks (or scribbles) - become richer with the intermediate predictions (or additional user inputs). However, the existing methods make it impossible to fully exploit this rich source of information. We resolve the issue by leveraging memory networks and learning to read relevant information from all available sources. In the semi-supervised scenario, the previous frames with object masks form an external memory, and the current frame as the query is segmented using the information in the memory. Similarly, to work with user interactions, the frames that are given user inputs form the memory that guides segmentation. Internally, the query and the memory are densely matched in the feature space, covering all the space-time pixel locations in a feed-forward fashion. The abundant use of the guidance information allows us to better handle challenges such as appearance changes and occlusions. We validate our method on the latest benchmark sets and achieve state-of-the-art performance along with a fast runtime.

7.
IEEE Trans Image Process ; 31: 5383-5395, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35749323

RESUMO

A holistic understanding of dynamic scenes is of fundamental importance in real-world computer vision problems such as autonomous driving, augmented reality and spatio-temporal reasoning. In this paper, we propose a new computer vision benchmark: Video Panoptic Segmentation (VPS). To study this important problem, we present two datasets, Cityscapes-VPS and VIPER together with a new evaluation metric, video panoptic quality (VPQ). We also propose VPSNet++, an advanced video panoptic segmentation network, which simultaneously performs classification, detection, segmentation, and tracking of all identities in videos. Specifically, VPSNet++ builds upon a top-down panoptic segmentation network by adding pixel-level feature fusion head and object-level association head. The former temporally augments the pixel features while the latter performs object tracking. Furthermore, we propose panoptic boundary learning as an auxiliary task, and instance discrimination learning which learns spatio-temporally clustered pixel embedding for individual thing or stuff regions, i.e., exactly the objective of the video panoptic segmentation problem. Our VPSNet++ significantly outperforms the default VPSNet, i.e., FuseTrack baseline, and achieves state-of-the-art results on both Cityscapes-VPS and VIPER datasets. The datasets, metric, and models are publicly available at https://github.com/mcahny/vps.

8.
Investig Clin Urol ; 63(2): 126-139, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35244986

RESUMO

PURPOSE: To evaluate the clinical efficacy and safety of tumor enucleation (TE) compared with partial nephrectomy (PN) for T1 renal cell carcinoma. MATERIALS AND METHODS: According to protocol, we searched multiple data sources for published and unpublished randomized controlled trials and nonrandomized studies (NRSs) in any language. We performed systematic review and meta-analysis according to the Cochrane Handbook for Systematic Reviews of Interventions and rated the certainty of the evidence (CoE) using the GRADE framework. RESULTS: We are uncertain about the effects of TE on perioperative (mean difference [MD] 3.38, 95% CI 1.52 to 5.23; I²=68%; 4 NRSs; 942 participants; very low CoE) and long-term (MD 2.31, 95% CI -1.40 to 6.01; I²=57%; 4 NRSs; 542 participants; very low CoE) residual renal function. TE may result in little to no difference in short-term residual renal function (MD 1.04, 95% CI 0.25 to 1.83; I²=0%; 2 NRSs; 256 participants; low CoE). We are uncertain about the effects of TE on cancer-specific mortality (risk ratio [RR] 0.90, 95% CI: 0.11 to 7.28; I²=0%; 2 NRSs; 551 participants; very low CoE) and major adverse events (RR 0.48, 95% CI: 0.30 to 0.79; I²=0%; 10 NRS; 2,360 participants; very low CoE). CONCLUSIONS: While TE appears to have similar effects on short term postoperative residual renal function, there were uncertainties on mortality and major adverse events. However, we need rigorous RCTs to elucidate the effects of TE as the evidence stems mostly from NRSs.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Carcinoma de Células Renais/cirurgia , Progressão da Doença , Feminino , Humanos , Neoplasias Renais/cirurgia , Masculino , Nefrectomia/efeitos adversos , Período Pós-Operatório
9.
J Korean Med Sci ; 26(1): 33-41, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21218027

RESUMO

This study was conducted to evaluate treatment outcome, mortality, and predictors of both in patients with multidrug-resistant tuberculosis (MDR-TB) at 3 TB referral hospitals in the public sector of Korea. We included MDR-TB patients treated at 3 TB referral hospitals in 2004 and reviewed retrospectively their medical records and mortality data. Of 202 MDR-TB patients, 75 (37.1%) had treatment success and 127 (62.9%) poor outcomes. Default rate was high (37.1%, 75/202), comprising 59.1% of poor outcomes. Male sex (adjusted odds ratio [aOR], 2.91; 95% confidence interval [CI], 1.13-7.49), positive smear at treatment initiation (aOR, 5.50; 95% CI, 1.22-24.90), and extensively drug-resistant TB (aOR, 10.72; 95% CI, 1.23-93.64) were independent predictors of poor outcome. The all-cause mortality rate was 31.2% (63/202) during the 3-4 yr after treatment initiation. In conclusion, the treatment outcomes of patients with MDR-TB at the 3 TB hospitals are poor, which may reflect the current status of MDR-TB in the public sector of Korea. A more comprehensive program against MDR-TB needs to be integrated into the National Tuberculosis Program of Korea.


Assuntos
Antituberculosos/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Demografia , Farmacorresistência Bacteriana Múltipla , Quimioterapia Combinada , Feminino , Hospitais de Doenças Crônicas , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores Sexuais , Resultado do Tratamento , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
10.
Korean J Women Health Nurs ; 27(3): 209-219, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36311978

RESUMO

Purpose: The purpose of this study was to describe pregnant women's lived experiences of hospitalization due to preterm labor in Korea. Methods: This qualitative study adopted a phenomenological approach. Individual in-depth interviews were conducted with nine participants, over the age of 20 years, who had been hospitalized for more than 1 week after being diagnosed with preterm labor. All interviews were audio-taped and verbatim transcripts were made for analysis. The data were analyzed following Colaizzi's phenomenological method. Results: The participants' ages ranged from 26 to 36 years, and all were married women. They were hospitalized for 13.1 days on average. Five thematic clusters emerged from the analysis. 'Withstanding hospitalization for the fetus's well-being' describes women's feelings during preterm labor and their endurance during their prolonged hospitalization, rooted in their conviction that the fetus comes first. 'Endless frustration in the hospital' encompasses women's emotions while lying in bed and quietly thinking to themselves. 'Unmet physiological needs' describes participants' awareness of their inability to independently handle human physiological needs given the need for careful and limited movement. 'Gratitude for the support around oneself' reflects the support from family and medical staff. 'Shifting perceptions and accepting one's circumstances' describes accepting hospitalization and making efforts to spend their remaining time in the hospital in a meaningful way. Conclusion: The findings in this study provide a deeper understanding and insights into the experiences of Korean women with preterm labor during hospitalization, underscoring the need to develop interventions for these patients.

11.
IEEE Trans Pattern Anal Mach Intell ; 42(5): 1038-1052, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31831407

RESUMO

Video inpainting aims to fill in spatio-temporal holes in videos with plausible content. Despite tremendous progress on deep learning-based inpainting of a single image, it is still challenging to extend these methods to video domain due to the additional time dimension. In this paper, we propose a recurrent temporal aggregation framework for fast deep video inpainting. In particular, we construct an encoder-decoder model, where the encoder takes multiple reference frames which can provide visible pixels revealed from the scene dynamics. These hints are aggregated and fed into the decoder. We apply a recurrent feedback in an auto-regressive manner to enforce temporal consistency in the video results. We propose two architectural designs based on this framework. Our first model is a blind video decaptioning network (BVDNet) that is designed to automatically remove and inpaint text overlays in videos without any mask information. Our BVDNet wins the first place in the ECCV Chalearn 2018 LAP Inpainting Competition Track 2: Video Decaptioning. Second, we propose a network for more general video inpainting (VINet) to deal with more arbitrary and larger holes. Video results demonstrate the advantage of our framework compared to state-of-the-art methods both qualitatively and quantitatively. The codes are available at https://github.com/mcahny/Deep-Video-Inpainting, and https://github.com/shwoo93/video_decaptioning.

12.
Sci Rep ; 10(1): 9271, 2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32518283

RESUMO

Physical changes in arranged silver nanowires were monitored during progressive heating inside a transmission electron microscope. Using the in-situ experimental method, overall variation of silver nanowires and movement of the silver atoms could be assessed. The physical morphology of silver nanowires was rapidly transformed above 350 °C as they fused with each other, which led to extrusion of the silver atoms. Around 550 °C, silver nanowires were almost fused into one, filling a relatively large void between silver nanowires. However, above 575 °C, the united silver nanowire was completely cut off, starting from the region that was suspected to have defects. For the first time, the fusion of arranged silver nanowires and the configurational changes of silver atoms during heating were visualized, and the migration between silver atoms and the damage mechanism of silver nanowires were assessed. Moreover, the relationship of physical morphology and electrical property of silver nanowires according to the temperature were investigated using the ex-situ experimental method. As silver nanowires started to split at 300 °C, the electrical conductivity deteriorated greatly. Beyond 350 °C, the electrical conductivity was completely lost while silver nanowires disintegrated rapidly, and silver nanowires completely disappeared at 450 °C.

13.
Biotechnol J ; 13(2)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29027752

RESUMO

A novel strategy to achieve label-free multiplex DNA detection system based on the projected capacitive touchscreen is developed. Touchscreen panel is first fabricated by patterning the ITO (indium-tin-oxide) electrode array on the glass wafer, and the electrodes are modified with the respective capture probe DNA sequences complementary to hemagglutinin1 (H1), neuraminidase1 (N1), and matrix1 (M1) DNA to demonstrate the molecular diagnosis of H1N1 influenza virus as a model pathogen. DNA sample is applied to the electrodes to allow hybridization of target DNA with the corresponding complementary capture probe. As a result, the hybridization event significantly enhanced the capacitance on the electrode, which can be very conveniently detected by the projected capacitive touchscreen. Based on this design principle, the authors have successfully detected target regions of H1N1 influenza virus in a label-free multiplexed manner. This touchscreen-based detecting system would greatly benefit the point-of-care testing (POCT) in various diagnostic applications.


Assuntos
Técnicas Biossensoriais , Sondas de DNA/química , DNA Viral/isolamento & purificação , Capacitância Elétrica , Técnicas Eletroquímicas , Proteínas Virais/genética , Eletrodos , Desenho de Equipamento , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Neuraminidase , Compostos de Estanho/química
14.
RSC Adv ; 8(20): 11241-11246, 2018 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35541507

RESUMO

We herein describe a novel impedimetric method to determine alkaline phosphatase (ALP) activity based on the Cu2+-mediated oxidation of ascorbic acid on a specific DNA probe-modified electrode. In this method, pyrophosphate (PPi) capable of complexing with Cu2+ is employed as a substrate of the ALP enzyme. In the presence of ALP, PPi is hydrolyzed to phosphate (Pi), which is not able to entrap Cu2+. The free Cu2+ are specifically bound to a poly-thymine DNA probe immobilized on the electrode surface and reduced to form copper nanoparticles by a concomitant oxidation of ascorbic acid. As a result, the oxidation products of ascorbic acid are accumulated on the electrode surface, which consequently increase electron transfer resistance (R et) by interrupting the electron transfer on the electrode. On the other hand, in the absence of ALP, PPi remains intact to effectively capture Cu2+, consequently preventing the oxidation of ascorbic acid and the subsequent increase of R et. Based on this design principle, the change in R et, which is proportional to ALP activity, was measured by electrochemical impedance spectroscopy (EIS) and ALP activities were successfully determined down to 6.5 pM (7.2 U L-1) with excellent selectivity.

15.
Arch Pharm Res ; 41(5): 519-529, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29797242

RESUMO

Phytoestrogen (PE) has received considerable attention due to the physiological significance of its estrogenicity. Flemingia strobilifera (FS) has been used as a folk medicine in Asia for the treatment of inflammation, cancer, and infection; however, the estrogenic effects and chemical components of FS have not yet been reported. We aimed to uncover the estrogenic properties and PEs derived from FS using phytochemical and pharmacological evaluation. PEs from FS extract (FSE) were analyzed by NMR, HPLC, and MS. To evaluate estrogenic activity, FSE and its compounds were evaluated by in vitro and in vivo assays, including human estrogen receptor alpha (hERα) binding, estrogen response element (ERE)-luciferase reporter assays, and uterotrophic assays. FSE and its compounds 1-5 showed binding affinities for hERα and activated ERE transcription in MCF-7 cells. Additionally, FSE and compounds 1-5 induced MCF-7 cell proliferation and trefoil factor 1 (pS2) expression. In immature female rats, significant increases in uterine weight and pS2 gene were observed in FSE-treated groups. We identified estrogenic activities of FSE and its bioactive compounds, suggesting their possible roles as PEs via ERs. PEs derived from FSE are promising candidates for ER-targeted therapy for post-menopausal symptoms.


Assuntos
Fabaceae/química , Fitoestrógenos/farmacologia , Animais , Peso ao Nascer/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Fitoestrógenos/química , Fitoestrógenos/isolamento & purificação , Presenilina-2/genética , Ratos , Ratos Sprague-Dawley , Células Tumorais Cultivadas , Útero/efeitos dos fármacos
16.
IEEE Trans Image Process ; 26(5): 2311-2326, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28252398

RESUMO

We present a novel coded exposure video technique for multi-image motion deblurring. The key idea of this paper is to capture video frames with a set of complementary fluttering patterns, which enables us to preserve all spectrum bands of a latent image and recover a sharp latent image. To achieve this, we introduce an algorithm for generating a complementary set of binary sequences based on the modern communication theory and implement the coded exposure video system with an off-the-shelf machine vision camera. To demonstrate the effectiveness of our method, we provide in-depth analyses of the theoretical bounds and the spectral gains of our method and other state-of-the-art computational imaging approaches. We further show deblurring results on various challenging examples with quantitative and qualitative comparisons to other computational image capturing methods used for image deblurring, and show how our method can be applied for protecting privacy in videos.

17.
Arch Neurol ; 63(11): 1648-51, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17101837

RESUMO

BACKGROUND: Concurrent development of retinal venous drainage and cerebral venous thrombosis has not been reported. Case Description We describe a 23-year-old man with bilateral central retinal vein occlusions and cerebral venous thrombosis. Initially observed bilateral hemorrhagic retinopathy and thrombus in the right transverse sinus of the patient began to resolve after 2 weeks of low-molecular-weight heparin. Hemorrhagic retinopathy progressively improved to previous visual acuity and the right lateral sinus remained patent by maintenance of anticoagulation with warfarin. CONCLUSION: The present case shows effectiveness of low-molecular-weight heparin for the initial management of hemorrhagic retinopathy of central retinal vein occlusion combined with cerebral venous thrombosis.


Assuntos
Anticoagulantes/uso terapêutico , Veias Cerebrais , Oclusão da Veia Retiniana/tratamento farmacológico , Trombose Venosa/tratamento farmacológico , Trombose Venosa/patologia , Adulto , Heparina/uso terapêutico , Humanos , Masculino , Oclusão da Veia Retiniana/complicações , Oclusão da Veia Retiniana/patologia , Fatores de Tempo , Trombose Venosa/complicações , Varfarina/uso terapêutico
18.
IEEE Trans Pattern Anal Mach Intell ; 37(7): 1501-13, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26352455

RESUMO

We present a calibration method of a time-of-flight (ToF) sensor and a color camera pair to align the 3D measurements with the color image correctly. We have designed a 2.5D pattern board with irregularly placed holes to be accurately detected from low resolution depth images of a ToF camera as well as from high resolution color images. In order to improve the accuracy of the 3D measurements of a ToF camera, we propose to perform ray correction and range bias correction. We reset the transformation of the ToF sensor which transforms the radial distance into the scene depth in Cartesian coordinate through ray correction. Then we capture a planar scene from different depths to correct the distance error that is shown to be dependent not only on the distance but also on the pixel location. The range error profiles along the calibrated distance are classified according to their wiggling shapes and each cluster of profiles with similar shape are separately estimated using a B-spline function. The standard deviation of the remaining random noise is recorded as an uncertainty information of distance measurements. We show the performance of our calibration method quantitatively and qualitatively on various datasets, and validate the impact of our method by demonstrating an RGB-D shape refinement application.

19.
IEEE Trans Pattern Anal Mach Intell ; 37(6): 1219-32, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26357344

RESUMO

This paper introduces a new high dynamic range (HDR) imaging algorithm which utilizes rank minimization. Assuming a camera responses linearly to scene radiance, the input low dynamic range (LDR) images captured with different exposure time exhibit a linear dependency and form a rank-1 matrix when stacking intensity of each corresponding pixel together. In practice, misalignments caused by camera motion, presences of moving objects, saturations and image noise break the rank-1 structure of the LDR images. To address these problems, we present a rank minimization algorithm which simultaneously aligns LDR images and detects outliers for robust HDR generation. We evaluate the performances of our algorithm systematically using synthetic examples and qualitatively compare our results with results from the state-of-the-art HDR algorithms using challenging real world examples.

20.
IEEE Trans Pattern Anal Mach Intell ; 35(1): 144-56, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22392701

RESUMO

We present a robust radiometric calibration framework that capitalizes on the transform invariant low-rank structure in the various types of observations, such as sensor irradiances recorded from a static scene with different exposure times, or linear structure of irradiance color mixtures around edges. We show that various radiometric calibration problems can be treated in a principled framework that uses a rank minimization approach. This framework provides a principled way of solving radiometric calibration problems in various settings. The proposed approach is evaluated using both simulation and real-world datasets and shows superior performance to previous approaches.


Assuntos
Algoritmos , Inteligência Artificial , Reconhecimento Automatizado de Padrão/métodos , Fotometria/métodos , Calibragem , Luz
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA