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1.
Phys Rev E ; 109(6-2): 065307, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39020909

RESUMO

We present a data-driven reduced-order modeling of the space-charge dynamics for electromagnetic particle-in-cell (EMPIC) plasma simulations based on dynamic mode decomposition (DMD). The dynamics of the charged particles in kinetic plasma simulations such as EMPIC is manifested through the plasma current density defined along the edges of the spatial mesh. We showcase the efficacy of DMD in modeling the time evolution of current density through a low-dimensional feature space. Not only do such DMD-based predictive reduced-order models help accelerate EMPIC simulations, they also have the potential to facilitate investigative analysis and control applications. We demonstrate the proposed DMD-EMPIC scheme for reduced-order modeling of current density and speedup in EMPIC simulations involving electron beam under the influence of magnetic field, virtual cathode oscillations, and backward wave oscillator.

2.
Arq Bras Oftalmol ; 87(4): e20220142, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38747753

RESUMO

Sympathetic ophthalmia is a rare and potentially devastating bilateral diffuse granulomatous panuveitis. It is caused by surgical or non-surgical eye injuries and is an uncommon and serious complication of trauma. It is diagnosed clinically and supported by imaging examinations such as ocular ultrasonography and optical coherence tomography. Its treatment consists of immunosuppressive therapy with steroids and sometimes steroid-sparing drugs, such as cyclosporine, azathioprine, cyclophosphamide, and mycophenolate mofetil. Fast and effective management with systemic immunosuppressive agents allows for disease control and achievement of good visual acuity in the sympathizing eye. By contrast, enucleation should be considered only in situations where the injured eye has no light perception or in the presence of severe trauma. In addition to a bibliographic review of this topic, we report six cases involving different immunosuppressive and surgical treatment modalities.


Assuntos
Imunossupressores , Oftalmia Simpática , Humanos , Oftalmia Simpática/tratamento farmacológico , Imunossupressores/uso terapêutico , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Linfócitos T/imunologia , Tomografia de Coerência Óptica/métodos , Acuidade Visual
3.
Arq. bras. oftalmol ; 87(4): e2022, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1557103

RESUMO

ABSTRACT Sympathetic ophthalmia is a rare and potentially devastating bilateral diffuse granulomatous panuveitis. It is caused by surgical or non-surgical eye injuries and is an uncommon and serious complication of trauma. It is diagnosed clinically and supported by imaging examinations such as ocular ultrasonography and optical coherence tomography. Its treatment consists of immunosuppressive therapy with steroids and sometimes steroid-sparing drugs, such as cyclosporine, azathioprine, cyclophosphamide, and mycophenolate mofetil. Fast and effective management with systemic immunosuppressive agents allows for disease control and achievement of good visual acuity in the sympathizing eye. By contrast, enucleation should be considered only in situations where the injured eye has no light perception or in the presence of severe trauma. In addition to a bibliographic review of this topic, we report six cases involving different immunosuppressive and surgical treatment modalities.


RESUMO A oftalmia simpática consiste em uma panuveíte granulomatosa bilateral rara e potencialmente devastadora, ocorrendo geralmente após trauma ocular cirúrgico ou não cirúrgico. O diagnóstico é baseado em aspectos clínicos e apoiado por exames de imagem, como ultrassonografia ocular e tomografia de coerência óptica. O tratamento consiste em terapia imunossupressora com esteróides e, eventualmente, drogas poupadoras de esteróides, como ciclosporina, azatioprina, ciclofosfamida e micofonato de mofetila. O manejo rápido e eficaz com agentes imunossupressores sistêmicos permite o controle da doença e a obtenção de boa acuidade visual no olho simpatizante. A enucleação, por outro lado, poderia ser considerada apenas em situações em que o olho lesado não tem percepção luminosa ou há trauma grave. Além de uma revisão bibliográfica sobre o tema, foi relatada uma série de 6 casos com diferentes modalidades de tratamento imunossupressor e cirúrgico.

4.
Sensors (Basel) ; 23(20)2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37896614

RESUMO

Propellant mass gauging under micro-gravity conditions is a challenging task due to the unpredictable position and shape of the fuel body inside the tank. Micro-gravity conditions are common for orbiting satellites and rockets that operate on limited fuel supplies. Capacitance sensors have been investigated for this task in recent years; however, the effect of various positions and shapes of the fuel body is not analyzed in detail. In this paper, we investigate this with various fill types, such as annular, core-annular, and stratified fills at different positions. We compare the performance among several curve-fitting-based approaches and a machine-learning-based approach, the latter of which offers superior performance in estimating the fuel content.

7.
Int Ophthalmol ; 43(8): 3023-3030, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37004606

RESUMO

PURPOSE: The purpose of the study was to describe the vitreal, retinal, and choroidal features of eyes affected by endogenous endophthalmitis (EE) and evaluate the effects of systemic antifungal drug treatment and pars plana vitrectomy by using spectral domain optical coherence tomography (SD-OCT). METHODS: Medical records and SD-OCT images of eyes diagnosed with EE at a single uveitis tertiary referral center in Brazil were acquired at the time of diagnosis, after 7 days of high-dose antifungal drug treatment, and at follow-up assessments performed 30 days after resolution. RESULTS: Thirteen eyes were enrolled in the study. All patients showed hyperreflective round-shaped lesions on SD-OCT and pre-retinal aggregates. Five eyes responded to antifungal systemic oral drugs despite showing vitreous opacity. The response to treatment was observable on optical coherence tomography (OCT) images. CONCLUSION: Fungal endophthalmitis showed typical features on SD-OCT, facilitating early diagnosis and treatment despite the absence of vitreous culture or biopsy. This study suggests that OCT images can be used to support diagnosis by physicians who do not have access to vitreoretinal surgery.


Assuntos
Endoftalmite , Uveíte , Humanos , Tomografia de Coerência Óptica/métodos , Antifúngicos , Uveíte/diagnóstico , Uveíte/cirurgia , Endoftalmite/diagnóstico , Vitrectomia/métodos , Estudos Retrospectivos
10.
Ocul Immunol Inflamm ; 31(4): 843-846, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35404726

RESUMO

INTRODUCTION: Ampiginous Choroiditis is a rare posterior uveitis that combines clinical features of Acute Multifocal Posterior Placoid Pigment Epitheliopathy and Serpiginous Chorioretinitis. Its pathophysiology is poorly understood and further studies are necessary to understand which mechanisms start the immunologic reaction. CASE REPORT: The purpose of this article is to report a well-documented case of Ampiginous Choroiditis following in seven days a RT-PCR confirmed SARS-CoV-2 infection, suggesting that the infection might have contributed as a trigger. CONCLUSION: Timely diagnosis and correct treatment are paramount to improve the visual outcomes, and the patient had successful response to systemic steroids.


Assuntos
COVID-19 , Coriorretinite , Corioidite , Uveíte Posterior , Síndrome dos Pontos Brancos , Humanos , COVID-19/complicações , COVID-19/diagnóstico , SARS-CoV-2 , Corioidite/diagnóstico , Corioidite/tratamento farmacológico , Coriorretinite/diagnóstico , Síndrome dos Pontos Brancos/diagnóstico , Angiofluoresceinografia
20.
Coluna/Columna ; 21(2): e258863, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1375243

RESUMO

ABSTRACT Objective: To compare pharmacological and non-pharmacological prophylaxis in elective spine surgery to determine the risks of DVT, PTE, and epidural hematoma (EH) in both groups, as well as their respective treatment effectiveness. Methods: Systematic review and meta-analysis based on systematically searched articles, using combinations of MeSH terms related to chemoprophylaxis and non-chemoprophylaxis for prevention of deep vein thrombosis and pulmonary embolism in elective spine surgery. Adult patients were eligible for inclusion in the study, except for those with trauma, spinal cord injury, neoplasms, or those using vena cava filters. Results: Five studies were selected for this systematic review and meta-analysis: 3 retrospective studies, 1 prospective study, and 1 case series. Data analysis showed that 4.64% of patients treated with chemoprophylaxis had an unfavorable outcome regarding DVT, while this outcome occurred in 1.14% of patients not treated with chemoprophylaxis (p=0.001). Among patients using chemoprophylaxis, only 0.1% developed epidural hematoma and 0.38% developed PTE. Among those on non-pharmaceutical prophylaxis, 0.04% had EH (p=0.11) and 0.42% had PTE (p=0.45). Conclusions: No benefits were found for chemoprophylaxis as compared to non-chemoprophylaxis in preventing DVT in elective spine surgery, nor was there an increased risk of epidural hematoma or fatal thromboembolic events. Level of evidence III; Therapeutic studies; Investigation of treatment results.


RESUMO Objetivo: Comparar profilaxia farmacológica e não farmacológica em cirurgia eletiva da coluna vertebral, a fim de determinar os riscos de TVP, TEP e hematoma epidural (HE) em ambos os grupos, bem como a respectiva eficácia do tratamento. Métodos: Revisão sistemática e metanálise com base em artigos sistematicamente pesquisados, usando combinações de termos MESH relacionados à quimioprofilaxia e à não quimioprofilaxia para prevenção de trombose venosa profunda e embolia pulmonar em cirurgia eletiva da coluna vertebral. Pacientes adultos foram elegíveis para inclusão no estudo, exceto aqueles com trauma, lesão medular, neoplasias e aqueles que usavam filtros de veia cava. Resultados: Cinco estudos foram incluídos para fazer parte desta revisão sistemática e metanálise: três estudos retrospectivos, um prospectivo e um série de casos. A análise dos dados mostrou que 4,64% dos pacientes tratados com quimioprofilaxia tiveram um resultado desfavorável em relação à TVP, enquanto esse resultado ocorreu em 1,14% dos pacientes não tratados com quimioprofilaxia (p = 0,001). Entre os pacientes em uso de quimioprofilaxia, apenas 0,1% desenvolveram hematoma epidural (HE) e 0,38% desenvolveram TEP. Entre aqueles em profilaxia não medicamentosa, 0,04% apresentaram HE (p = 0,11) e 0,42% tiveram TEP (p = 0,45). Conclusões: Não foram encontrados benefícios para a quimioprofilaxia quando comparada à não quimioprofilaxia na prevenção da TVP em cirurgia eletiva da coluna vertebral, assim como não foi verificado aumento do risco de hematoma epidural ou eventos tromboembólicos fatais. Nível de evidência III; Estudos terapêuticos - Investigação dos resultados do tratamento.


RESUMEN Objetivo: Comparar la profilaxis farmacológica y no farmacológica en la cirugía de columna electiva para determinar los riesgos de TVP, TEP y hematoma epidural (HE) en ambos grupos, así como la respectiva eficacia del tratamiento. Métodos: Revisión sistemática y metanálisis basados en artículos buscados sistemáticamente, utilizando combinaciones de términos MESH relacionados con quimioprofilaxis y no quimioprofilaxis para la prevención de trombosis venosa profunda y embolia pulmonar en cirugía electiva de columna. Se eligieron pacientes adultos para su inclusión en el estudio, excepto aquellos con traumatismos, lesión medular, neoplasias y aquellos que usan filtros de vena cava. Resultados: Se incluyeron cinco estudios para formar parte de esta revisión sistemática y metanálisis: 3 estudios retrospectivos, 1 prospectivo y 1 serie de casos. El análisis de los datos reveló que el 4,64% de los pacientes tratados con quimioprofilaxis tuvieron un resultado desfavorable con respecto a la TVP, mientras que este resultado se produjo en el 1,14% de los pacientes no tratados con quimioprofilaxis (p = 0,001). Entre los pacientes que recibieron quimioprofilaxis, sólo el 0,1% desarrolló hematoma epidural (HE) y el 0,38% desarrolló TEP. Entre los que recibieron profilaxis no farmacológica, el 0,04% desarrolló HE (p = 0,11) y el 0,42% desarrolló TEP (p = 0,45). Conclusiones: No se encontraron beneficios para la quimioprofilaxis en comparación con la no quimioprofilaxis para prevenir la TVP en la cirugía de columna electiva, así como tampoco un mayor riesgo de hematoma epidural o eventos tromboembólicos fatales. Nivel de evidencia - III; Estudios terapéuticos - Investigación de los resultados del tratamiento.


Assuntos
Terapêutica , Ortopedia , Hematoma Epidural Espinal
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