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1.
Sensors (Basel) ; 24(2)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38257478

RESUMO

Rigid-reflector spaceborne antennas (RRSAs) are well-suited for high-frequency application scenarios due to their high surface accuracy. However, the low stowing efficiency of RRSAs limits the aperture diameters and further deteriorates the electromagnetic (EM) performances in terms of gain, resolution and sensitivity. After conducting systematic feature analysis with respect to several typical RRSAs, we propose a novel type of RRSA to solve the aforementioned problems. Inspired by the pose adjustment process for a higher stowing efficiency of traditional RRSAs, we also propose a new segmentation scheme of a reflective surface consisting of a deviation-angle panel that facilitates a higher stowing efficiency. Based on this scheme, its corresponding folded configuration is implemented by combining Euler's rotation theorem and the idea of parameter identification. In addition, we also compare the stowing efficiency of different schemes to verify the high stowing efficiency of the configuration. Finally, we perform mechanism/structure design and deployment dynamics to demonstrate that the antenna can be successfully deployed and exhibits excellent deployment quality. The results suggest that the proposed antenna possesses higher stowing efficiency than that of the same kind, with a stable deployment and interference-free process.

2.
ACS Sens ; 8(9): 3458-3467, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37639526

RESUMO

Diffusion limitations and nonspecific surface absorption are great challenges for developing micro-/nanoscale affinity biosensors. There are very limited approaches that can solve these issues at the same time. Here, an acoustic streaming approach enabled by a gigahertz (GHz) resonator is presented to promote mass transfer of analytes through the jet mode and biofouling removal through the shear mode, which can be switched by tuning the deviation angle, α, between the resonator and the sensor. Simulations show that the jet mode (α ≤ 0) drives the analytes in the fluid toward the sensing surface, overcomes the diffusion limitation, and enhances the binding; while the shear mode (0 < α < π/4) provides a scouring action to remove the biofouling from the sensor. Experimental studies were performed by integrating this GHz resonator with optoelectronic sensing systems, where a 34-fold enhancement for the initial binding rate was obtained. Featuring high efficiency, controllability, and versatility, we believe that this GHz acoustic streaming approach holds promise for many kinds of biosensing systems as well as lab-on-chip systems.


Assuntos
Acústica , Incrustação Biológica , Difusão
3.
BMC Ophthalmol ; 23(1): 185, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37101193

RESUMO

BACKGROUND: Patients with strabismus are more likely to have mental health problems, including high rates of depressive symptoms and social phobia. Intermittent exotropia (IXT) typically occurs in early childhood and is more common in Asian populations. We aim to assess the health-related quality of life (HRQOL) concerns in children with intermittent exotropia (IXT) using the Intermittent Exotropia Questionaire (IXTQ), and their associations with the clinical severity of IXT and the parents' HRQOL concerns. METHODS: IXT, defined as both distance and near exodeviation ≥ 10 prism diopters were eligible for inclusion. The final IXTQ score is calculated using the mean score for all items, and ranges from 0 (worst HRQOL) to 100 (best HRQOL). The correlations of child IXTQ scores with their deviation angle and stereoacuity were measured, as were those with their parent's IXTQ scores. RESULTS: One hundred twenty-two children with IXT (aged 5-17 years) and one parent for each child completed the child and parent IXTQ, respectively. The greatest HRQOL concern for each child with IXT and their parent was "Worry about eyes" (frequency 88%, score 35.0 ± 27.8). Lower child IXTQ scores were associated with a larger distance (r = 0.24, p = 0.007) and near deviation angle (r = 0.2, p = 0.026). "It bothers me because I have to wait for my eyes to clear up" and "Waiting for their eyes to clear up" were more common in children with a larger deviation angle (both p < 0.05). The parent IXTQ scores (52.1 ± 25.3) were lower than the child ones (79.7 ± 15.8) and showed a positive correlation with child IXTQ scores (r = 0.26, p = 0.004). Lower parent IXTQ scores were associated with poor distance stereoacuity (r = 0.23, p = 0.01). CONCLUSION: The HRQOL of IXT children was positively related to that of their parents. A larger deviation angle and worse distance stereoacuity function may predict more-negative impacts on children and their parents, respectively.


Assuntos
Exotropia , Qualidade de Vida , Criança , Humanos , Pré-Escolar , Qualidade de Vida/psicologia , Exotropia/diagnóstico , Perfil de Impacto da Doença , Nível de Saúde , Pais/psicologia , República da Coreia/epidemiologia
4.
Cranio ; : 1-5, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36242559

RESUMO

BACKGROUND: Pterygoid hamulus syndrome, a painful oral and facial syndrome, has been described in literature to be correlated with morphological changes in the length of the pterygoid hamulus of the sphenoid bone. CLINICAL PRESENTATION: The current case report describes the treatment for severe, continuous pain in the posterior right palate. Despite numerous conservative treatments given to the patient, no improvement was seen. Cone beam computed tomography (CBCT) measurements revealed an elongation as well as a significant medial deviation of the lower extremity of the medial pterygoid plate. The surgical resection was performed under local anesthesia. The pain subsided two days after the surgery, and there were no relapses in the weeks that followed. CONCLUSION: The medial deviation of the hamulus appeared to be important in the etiology of this painful syndrome. Additional research based on CBCT measurements will be required.

5.
Artigo em Chinês | MEDLINE | ID: mdl-36036065

RESUMO

Objective:To investigate the effect of different rotations modes of control rod on testing results of the subjective visual vertical (SVV). Methods:Twenty-four normal young volunteers were selected for this study, and the control rod of SVV was rotated in clockwise, counterclockwise and any direction at the head tilt-positions of 0°, 45° left and 45° right. The differences of SVV deflection angle values at different rotation modes were analyzed. Results:①The deviation angle values of SVV obtained by rotating the control rod in clockwise, counterclockwise and any direction at the head tilt-positions of 0° were 1.56°±0.21°, 3.05°±0.24°, and 2.16°±0.22°, respectively,and the difference was statistically significant (P<0.05),the deviation angle value of SVV in clockwise direction was smaller; ②At head tilt-positions of 45° left, the SVV deviation angle values obtained by rotating the control rod in three rotation modes were 2.59°±0.53°, 4.03°±0.51°, and 3.49°±0.54°, respectively, and the difference was statistically significant(P<0.05),the deviation angle value in the clockwise direction was also smaller; ③At the head tilt-positions of 45° right, the SVV deviation angle values in three modes were 4.68°±0.58°, 7.23°±0.72°, and 5.93°±0.96°, respectively, and the difference was statistically significant (P<0.05),the deviation value of SVV was also smaller when rotated in the clockwise direction; ④Comparison of SVV deviation angle values in three rotation modes at the head tilt-positions of 45° left and 45° right showed that there was no statistical difference in clockwise and in any direction (P>0.05), while the difference was statistically significant when rotated in the counterclockwise direction (P<0.05). Conclusion:Different rotation modes of the control rod during SVV testing will affect the test results. Rotating the control rod in clockwise direction to make the SVV values more accurate is recommended.


Assuntos
Percepção Visual , Humanos
6.
J Foot Ankle Surg ; 60(5): 1079-1087, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34140201

RESUMO

Bunionette deformities have been treated as an analog of hallux valgus, and the surgical techniques are similar. Most commonly anteroposterior image is evaluated pre- and postoperatively. To our knowledge, only one study has evaluated changes on the lateral radiograph and no study has evaluated changes in rotation of the fifth metatarsal head postoperatively. In percutaneous bunionette correction using a burr for osteotomy, shortening of the fifth metatarsal and elevation of the metatarsal head are inevitable. Without fixation, there is also a possibility of rotational change to the metatarsal head. We measured parameters on anteroposterior and lateral weightbearing radiographs in 18 feet pre- and postoperatively. Rotation of the fifth metatarsal head was graded according to the medial tubercle location. We also evaluated angular change of the fifth metatarsal on weightbearing lateral radiographs. Percutaneous bunionette correction without fixation could achieve satisfactory clinical and radiographic results, with less complication, when compared with previously published outcomes of open and percutaneous surgery with fixation. In this surgical method, bunionette is corrected in 3 dimensions. To our knowledge, this is the first study to evaluate rotation of the metatarsal head and change in the sagittal angle of the fifth metatarsal after bunionette correction.


Assuntos
Joanete do Alfaiate , Joanete , Hallux Valgus , Ossos do Metatarso , Hallux Valgus/diagnóstico por imagem , Hallux Valgus/cirurgia , Humanos , Ossos do Metatarso/diagnóstico por imagem , Ossos do Metatarso/cirurgia , Rotação
7.
Orthop Surg ; 12(6): 1597-1604, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32776484

RESUMO

OBJECTIVE: To investigate the clinical and radiological outcomes in patients with monoarticular rheumatoid arthritis of the fifth metatarsophalangeal joint after Weil osteotomy. METHODS: From July 2011 to September 2015, 18 feet of 16 rheumatoid arthritis patients who underwent Weil osteotomy of the fifth metatarsal toe with a mean age at the time of surgery of 48.8 ± 7.4 years were reviewed retrospectively. The mean disease duration was 44.6 ± 6.8 months, and the follow-up period was 36 months. Clinical outcomes were evaluated according to the American Orthopaedic Foot and Ankle Society lesser metatarsophalangeal interphalangeal scale (AOFAS), 10-item SF-36 physical functioning and 2-item SF-36 bodily pain, Visual Analogue Scale (VAS), and satisfaction scores. In the radiologic evaluation, fifth metatarsophalangeal angle (MTP-5), lateral deviation angle (LDA), and longitudinal axes of the fifth metatarsal were measured on anterior-posterior (AP) weight-bearing radiographs preoperative and at the last follow-up. RESULTS: Clinical assessment showed that the total average of AOFAS was significantly increased from preoperative 53.6 ± 9.0 to 98.7 ± 2.0 points, and the VAS score was significantly decreased from preoperative 4.1 ± 1.5 to 1.1 ± 0.8 points at the last follow-up (P < 0.001). The total averages of SF-36 physical functioning and SF-36 bodily pain were significantly increased from preoperative 48.9 ± 9.0 to 99. ± 2.1 and from 61.4 ± 12.1 to 99.4 ± 2.4 points, respectively, at the last follow-up (P < 0.001). Subjectively, the excellent outcome of the surgery results were rated by 13 patients (81.3%) that underwent surgery and three patients (18.7%) were rated as good. Regarding radiographic parameters, the mean MTP-5 significantly decreased from 21.5° ± 1.2° preoperatively to 10.2° ± 1.2°, the mean LDA significantly decreased from 7.1° ± 1.2° preoperatively to -2.4° ± 1.0°, and the mean length of the fifth metatarsal was significantly shortened from 71.5 ± 1.4 preoperatively to 67.8 ± 1.5 mm at the final follow-up visit (P < 0.001). No malunion, nonunion, necrosis, pseudoarthrosis, or fracture of the fifth metatarsal was found. No exuberant bone growth, perforation of the screw, subluxation, or dislocation was observed. No indications of modification, revision or repeat surgery, or delayed wound healing were observed during follow-up period. CONCLUSION: Surgical management of the monoarticular rheumatoid arthritis of the fifth metatarsophalangeal joint can achieve good clinical and radiological outcomes, with pain relief and dislocation reduction, as well as high satisfaction and improvement without recurrence or progression during the follow-up period.


Assuntos
Artrite Reumatoide/cirurgia , Articulação Metatarsofalângica/cirurgia , Osteotomia/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Satisfação do Paciente , Estudos Retrospectivos , Inquéritos e Questionários
8.
Acta Crystallogr A Found Adv ; 75(Pt 3): 517-526, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31041907

RESUMO

For the asymmetrical Bragg case the X-ray plane-wave reflection coefficients and rocking-curve dependences on the deviation angles from the exact Bragg orientation in the diffraction plane and in the direction perpendicular to the diffraction plane are analysed. The region of total reflection and its size dependence on two deviation angles are analysed as well. New peculiarities of the rocking curves are obtained.

9.
World Neurosurg ; 127: e288-e298, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30902779

RESUMO

OBJECTIVE: This retrospective cohort study aimed to investigate the change of spinal cord displacements and the occurrence of C5 palsy between anterior controllable antedisplacement and fusion (ACAF) (group A) and single open-door laminoplasty (group L). METHODS: From January 2016 to December 2017, a total of 80 patients with cervical ossification of the posterior longitudinal ligament (OPLL) were enrolled. All patients underwent computed tomography and magnetic resonance imaging. The types and extent of OPLL, spinal cord rotation, deviation angle, and distance between the vertebral arteries line and spinal cord (DVS) were measured. Patients with postoperative C5 palsy were recorded. Neurologic function was evaluated by Japanese Orthopaedic Association (JOA) score. RESULTS: Three days after surgery, patients in group A had better recovery (6.7° ± 2.4°) of spinal cord rotation than group L (3.1° ± 0.8°; P < 0.05). Deviation angle showed similar changes to spinal cord rotation. At the final follow-up, patients in group A had decreased DVS (11.0 ± 0.7 mm), whereas patients in group L had increased DVS (15.1 ± 0.8 mm) compared with preoperation (P < 0.05). Five patients (1 in group A and 4 in group L) developed postoperative C5 palsy (P > 0.05). Patients in group A had a higher JOA score at the final follow-up than those in group L (P < 0.05). CONCLUSIONS: ACAF could achieve in situ decompression in terms of spinal cord rotation, deviation angle, and spinal cord shift with better clinical outcomes and relatively lower incidence of C5 palsy compared with single open-door laminoplasty.


Assuntos
Laminoplastia/métodos , Imageamento por Ressonância Magnética/métodos , Ossificação do Ligamento Longitudinal Posterior/cirurgia , Medula Espinal/patologia , Fusão Vertebral/métodos , Adulto , Idoso , Antropometria , Vértebras Cervicais , Descompressão Cirúrgica/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes de Compressão Nervosa/etiologia , Síndromes de Compressão Nervosa/reabilitação , Neuroimagem , Ossificação do Ligamento Longitudinal Posterior/diagnóstico por imagem , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/reabilitação , Período Pós-Operatório , Medula Espinal/diagnóstico por imagem , Raízes Nervosas Espinhais/diagnóstico por imagem , Raízes Nervosas Espinhais/fisiopatologia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
10.
Rev. bras. oftalmol ; 78(1): 11-14, jan.-fev. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-990792

RESUMO

Abstract Introduction: Muscular transposition procedures are used when there is no ocular rotation in a particular direction due to alterations of the extraocular muscles such as paralysis, agenesis or congenital anomalies. The objective of this study is to characterize the patients treated with this procedure and determine the percentage of correction of the deviation angle obtained after surgery in the Pediatric Ophthalmology, Strabismus and Neuro-ophthalmology Unit. "Dra. Ana María Illescas Putzeys", Hospital de ojos y oídos "Dr. Rodolfo Robles V. Methods: A retrospective, descriptive, observational study was conducted with review of records of patients operated on muscle transposition during the years 1999 to 2016. Results: Twenty-three rectus muscle transposition procedures were performed. Thirteen were male (56.5%). The mean age was 42 years. In our series, an average correction of 42 PD (82%) was obtained regardless of the type of paralysis or the surgical procedure performed. Conclusion: In selected cases of paralytic strabismus, the main approach may be only muscle transposition with augmentation (posterior intermuscular fixation suture), with good results, similar to those obtained with muscle transposition using adjuvants such as botulinum toxin treatment.


Resumo Introdução: Os procedimentos de transposição muscular são utilizados quando não há rotação ocular em nenhuma direção determinada devido a alterações dos músculos extraoculares, como paralisia, agenesia ou anomalias congênitas. O objetivo deste estudo é caracterizar os pacientes tratados com este procedimento e determinar a porcentagem de correção do ângulo de desvio obtida após a cirurgia na Unidade Pediátrica de Oftalmologia, Estrabismo e Neuro-Oftalmologia. "Dra. Ana María Illescas Putzeys", Hospital de ojos y oídos "Dr. Rodolfo Robles V. Métodos: Foi realizado um estudo retrospectivo, descritivo, observacional, com revisão dos registros de pacientes operados para transposição muscular nos anos de 1999 a 2016. Resultados: Foram realizados vinte e três procedimentos de transposição do músculo reto. Treze pacientes eram homens (56,5%). A idade média foi de 42 anos. Em nossa série, foi obtida uma correção média de 42 PD (82%), independente do tipo de paralisia ou do procedimento cirúrgico realizado. Conclusão: Em casos selecionados de estrabismo paralítico, a principal abordagem pode ser apenas a transposição muscular com aumento (sutura de fixação intermuscular posterior), com bons resultados semelhantes aos obtidos com a transposição muscular com a utilização de adjuvantes como o tratamento com toxina botulínica.


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Estrabismo/cirurgia , Músculos Oculomotores/cirurgia , Epidemiologia Descritiva , Estudos Retrospectivos , Estudo Observacional
11.
Acta Crystallogr A Found Adv ; 74(Pt 3): 204-215, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29724966

RESUMO

For the asymmetrical Laue case the X-ray plane-wave transmission and reflection coefficients and rocking curves are analysed as a function of the deviation angles from the exact Bragg orientation in the diffraction plane and in the direction perpendicular to the diffraction plane. New peculiarities of the rocking curves are obtained. The peculiarities of both the effective absorption coefficient and rocking curves in thick crystals are also investigated.

12.
J Appl Biomater Funct Mater ; 16(3): 115-125, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29582693

RESUMO

INTRODUCTION: The unilateral external fixator has become a quick and easy application for fracture stabilization of the extremities; the main value for evaluation of mechanical stability of the external fixator is stiffness. The stiffness property of the external fixator affects the local biomechanical environment of fractured bone. METHODS: In this study, a theoretical model with changing Young's modulus of the callus is established by using the Castigliano's theory, investigating compression stiffness, torsional stiffness and bending stiffness of the fixator-bone system during the healing process. The effects of pin deviation angle on three stiffness methods are also investigated. In addition, finite element simulation is discussed regarding the stress distribution between the fixator and bone. RESULTS: The results reveal the three stiffness evaluation methods are similar for the fixator-bone system. Finite element simulation shows that with increased healing time, the transmission of the load between the fixator and bone are different. In addition, the finite element analyses verify the conclusions obtained from the theoretical model. CONCLUSIONS: This work helps orthopedic doctors to monitor the progression of fracture healing and determine the appropriate time for removal of a fixation device and provide important theoretical methodology.


Assuntos
Calo Ósseo/fisiologia , Consolidação da Fratura/fisiologia , Modelos Teóricos , Módulo de Elasticidade , Fixadores Externos , Análise de Elementos Finitos , Fraturas Ósseas/fisiopatologia
13.
J Surg Res ; 193(2): 713-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25466517

RESUMO

BACKGROUND: Spinous process deviation is a common variation in lumbar spine, and some authors suggest that spinous process deviation may lead to imbalance between muscles on either side of the spinous process. We assume that spinous process deviation may be correlated to the disc degeneration in lumbosacral segment; however, no studies have been published in this regard. MATERIAL AND METHODS: A total of 465 outpatients with lumbar degenerative diseases were reviewed retrospectively, and the included patients were divided into three groups of L4 deviation, L5 deviation, and no deviation. The deviation angle of L4 and L5 spinous process was measured on computed tomography using Image J, the degeneration of the corresponding disc was evaluated on magnetic resonance imaging using the Modified Pfirrmann Grading System, and the correlation between spinous process deviation and lumbar disc degeneration was studied. RESULTS: A total of 118 cases were included in the present study, and there were 69 cases in the no deviation group, 30 in the L4 deviation group, and 19 in the L5 deviation group. No significant difference in the grade of disc degeneration between the no deviation group and L4 (P > 0.05) or L5 deviation group (P > 0.05) was noted. In the L4 and L5 deviation groups, there was no significant correlation between the deviation angle of spinous process and grade of corresponding intervertebral disc degeneration (P > 0.05). CONCLUSIONS: The deviation of spinous process does not correlate to the degeneration of intervertebral disc in lumbosacral segments.


Assuntos
Degeneração do Disco Intervertebral/patologia , Vértebras Lombares/patologia , Adulto , Idoso , Feminino , Humanos , Degeneração do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/patologia , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Estenose Espinal/diagnóstico por imagem , Estenose Espinal/patologia
14.
Artigo em Coreano | WPRIM (Pacífico Ocidental) | ID: wpr-147636

RESUMO

PURPOSE: To compare the changes in strabismus angle and deviation between two groups: a bilateral lateral rectus recession (Group 1) and a unilateral lateral rectus recession in exotropia (Group 2). METHODS: A retrospective survey was conducted on 198 patients who had received exotropia surgery in our ophthalmology clinic from September 2003 to April 2007. A total of 116 patients were in Group 1, and 82 patients were in Group 2. RESULTS: The average deviations of the first postoperative month and the first postoperative year were -1.96 D +/- 4.75, 2.5 D +/- 7.82 for Group 1 and 0.77 D +/- 2.87, 5.94 D +/- 3.38 for Group 2. Revealing statistical significance between the 2 Groups: Group 1 had 30 failure cases (25.9%) and their 1 postoperative year average deviation was 5.42 D +/- 13.97, while Group 2 showed 24 failure cases (29.3%) and their 1-postoperative-year average deviation was 13.0-79 +/- 3.04. Group 1 had less strabismus angle and a greater standard deviation than Group 2, as Group 1 had more overcorrection. Among the 30 failure cases of Group 1, 9 were overcorrected and 21 were undercorrected, but all 24 failure cases in Group 2 were undercorrected. CONCLUSIONS: The strabismus angle after lateral rectus recession showed a wider variation and a larger difference in bilateral lateral rectus recession than in the unilateral lateral rectus recession.


Assuntos
Humanos , Exotropia , Oftalmologia , Estudos Retrospectivos , Estrabismo
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