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1.
Opt Lett ; 49(7): 1741-1744, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38560851

RESUMO

Speckle-correlation optical scattering imaging (SCOSI) has shown the potential for non-invasive biomedical diagnostic applications, which directly utilizes the scattering patterns to reconstruct the deep and non-line-of-sight objects. However, the course of the translation of this technique to preclinical biomedical imaging applications has been postponed by the following two facts: 1) the field of view of SCOSI was significantly limited by the optical memory effect, and 2) the molecular-tagged functional imaging of the biological tissues remains largely unexplored. In this work, a proof-of-concept design of the first-generation widefield functional SCOSI (WF-SCOSI) system was presented for simultaneously achieving mesoscopic mapping of fluid morphology and flow rate, which was realized by implementing the concepts of scanning synthesis and fluorescence scattering flowmetry. The ex vivo imaging results of the fluorescence-labeled large-scale blood vessel network phantom underneath the strong scatters demonstrated the effectiveness of WF-SCOSI toward non-invasive hemodynamic imaging applications.


Assuntos
Diagnóstico por Imagem , Hemodinâmica , Imagens de Fantasmas , Reologia , Desenho de Equipamento , Imagem Óptica/métodos
2.
Artigo em Inglês | MEDLINE | ID: mdl-38562440

RESUMO

Objective: To comparison of the application of Vibrating Mesh Nebulizer and Jet Nebulizer in chronic obstructive pulmonary disease (COPD). Research Methods: This systematic review and meta-analysis was conducted following the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) statements. The primary outcome measures analyzed included: The amount of inhaler in the urine sample at 30 minutes after inhalation therapy (USAL0.5), The total amount of inhaler in urine sample within 24 hours (USAL24), Aerosol emitted, Forced expiratory volume in 1 second (FEV1), Forced vital capacity (FVC). Results: Ten studies were included with a total of 314 study participants, including 157 subjects in the VMN group and 157 subjects in the JN group. The data analysis results of USAL0.5, MD (1.88 [95% CI, 0.95 to 2.81], P = 0.000), showed a statistically significant difference. USAL24, MD (1.61 [95% CI, 1.14 to 2.09], P = 0.000), showed a statistically significant difference. The results of aerosol emitted showed a statistically significant difference in MD (3.44 [95% CI, 2.84 to 4.04], P = 0.000). The results of FEV1 showed MD (0.05 [95% CI, -0.24 to 0.35], P=0.716), the results were not statistically significant. The results of FVC showed MD (0.11 [95% CI, -0.18 to 0.41], P=0.459), the results were not statistically significant. It suggests that VMN is better than JN and provides higher aerosols, but there is no difference in improving lung function between them. Conclusion: VMN is significantly better than JN in terms of drug delivery and utilization in the treatment of patients with COPD. However, in the future use of nebulizers, it is important to select a matching nebulizer based on a combination of factors such as mechanism of action of the nebulizer, disease type and comorbidities, ventilation strategies and modes, drug formulations, as well as cost-effectiveness, in order to achieve the ideal treatment of COPD.


Assuntos
Broncodilatadores , Doença Pulmonar Obstrutiva Crônica , Humanos , Administração por Inalação , Albuterol , Broncodilatadores/efeitos adversos , Sistemas de Liberação de Medicamentos , Desenho de Equipamento , Nebulizadores e Vaporizadores , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Aerossóis e Gotículas Respiratórios
3.
PLoS One ; 19(4): e0300616, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38598530

RESUMO

This paper presents a groundbreaking Ku-band 20W RF front-end power amplifier (PA), designed to address numerous challenges encountered by satellite communication systems, including those pertaining to stability, linearity, cost, and size. The manuscript commences with an exhaustive discussion of system design and operational principles, emphasizing the intricacies of low-noise amplification, and incorporating key considerations such as noise factors, stability analysis, gain, and gain flatness. Subsequently, an in-depth study is conducted on various components of the RF chain, including the pre-amplification module, driver-amplification module, and final-stage amplification module. The holistic design extends to the inclusion of the display and control unit, featuring the power-control module, monitoring module, and overall layout design of the PA. It is meticulously tailored to meet the specific demands of satellite communication. Following this, a thorough exploration of electromagnetic simulation and measurement results ensues, providing validation for the precision and reliability of the proposed design. Finally, the feasibility of that design is substantiated through systematic system design, prototype production, and exhaustive experimental testing. It is noteworthy that, in the space-simulation environmental test, emphasis is placed on the excellent performance of the Star Ku-band PA within the 13.75GHz to 14.5GHz frequency range. Detailed power scan measurements reveal a P1dB of 43dBm, maintaining output power flatness < ± 0.5dBm across the entire frequency and temperature spectrum. Third-order intermodulation scan measurements indicate a third-order intermodulation of ≤ -23dBc. Detailed results of power monitoring demonstrate a range from +18dBm to +54dBm. Scans of spurious suppression and harmonic suppression, meanwhile, show that the PA evinces spurious suppression ≤ -65dBc and harmonic suppression ≤ -60dBc. Rigorous phase-scan measurements exhibit a phase-shift adjustment range of 0° to 360°, with a step of 5.625°, and a phase-shift accuracy of 0.5dB. Detailed data from gain-scan measurements show a gain-adjustment range of 0dB to 30dB, with a gain flatness of ± 0.5dB. Attenuation error is ≤ 1%. These test parameters perfectly align with the practical application requirements of the technical specifications. When compared to existing Ku-band PAs, our design reflects a deeper consideration of specific requirements in satellite communication, ensuring its outstanding performance and uniqueness. This PA features good stability, high linearity, low cost, and compact modularity, ensuring continuous and stable power output. These features position the proposed system as a leader within the market. Successful orbital deployment not only validates its operational stability; it also makes a significant contribution to the advancement of China's satellite PA technology, generating positive socio-economic benefits.


Assuntos
Amplificadores Eletrônicos , Comunicações Via Satélite , Reprodutibilidade dos Testes , Desenho de Equipamento , Simulação por Computador
4.
PLoS One ; 19(4): e0299896, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38568900

RESUMO

The objective was to evaluate the effect of glide path and coronal flaring on the dentin volume removal and percentage of touched walls in curved canals using two heat-treated rotary files. The mesiobuccal canal of forty-eight, randomly selected, extracted mandibular molars was divided into two groups of 24 each, according to the type of instrument used (RACE EVO and EdgeSequel rotary files). Each group was further divided into three subgroups; Group (A): Control using one file shaped to 04/30, Group (B) with a glide path (EdgeGlidePath (EGP)), and Group (C): with a glide path and coronal flaring (EGP and EdgeTaper Platinum (ETP) SX file respectively). The root canals were then instrumented using the assigned instruments. The assessment was carried out using micro-CT. The comparison of the mean values of the tested groups about dentin volume removal and percentage of untouched walls did not reach statistical significance (p<0.05). Glide path and coronal flaring had an insignificant effect on the dentin volume removal and percentage of untouched walls in curved canals.


Assuntos
Temperatura Alta , Níquel , Preparo de Canal Radicular , Microtomografia por Raio-X/métodos , Preparo de Canal Radicular/métodos , Ligas , Titânio , Cavidade Pulpar/diagnóstico por imagem , Cavidade Pulpar/cirurgia , Desenho de Equipamento
6.
Shanghai Kou Qiang Yi Xue ; 33(1): 54-58, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38583025

RESUMO

PURPOSE: To compare the forming ability of four kinds of nickel-titanium instrument preparation resin for simulated curved root canal. METHODS: A total of 40 single bend resin simulated root canals were randomly divided into 4 groups with 10 in each group. Four kinds of nickel-titanium instruments (ProTaper, HyFlex EDM, WaveOne Gold and Reciproc Blue) were used for root canal preparation, and divided into group A, group B, group C and group D. The preparation time of the four groups was compared, the root canal images before and after preparation were analyzed by computer image analysis software, and the changes of the preparation time, curvature and curvature radius of the four groups were recorded. With the root tip as the center of the circle, the radius of 1-10 mm was selected as concentric circle arcs. The detection points were overlapping root canal intersection points. The resin removal amount and center positioning force of the inner and outer walls of the root canal at different detection points were recorded. Statistical analysis was performed with SPSS 20.0 software package. RESULTS: The root canal preparation time in group A was significant longer than that in group B, C and D(P<0.05), but there was no significant difference in the curvature and curvature radius of the root canal among the four groups (P>0.05). The removal amount of resin from the root canal wall in group C was significant lower than that in group A, B and D (P<0.05) when the distance from the detection point to the apical foramina was 5, 6, 8, 9 and 10 mm, respectively. The removal amount of resin from the outer wall of the root canal in group C was significant lower than that in group A, B and D (P<0.05) when the distance from the detection point to the apical foramina was 5, 6, 7, 9 and 10 mm, respectively. The root tip offset of group A from the detection point to the apical hole of 1, 2, 3, 4, 6, 7, 8, 9 and 10 mm was significant greater than that of group B, C and D(P<0.05). CONCLUSIONS: Among the four instruments, ProTaper has the largest apical deviation, HyFlex EDM, WaveOne Gold and Reciproc Blue have better ability of root canal forming.


Assuntos
Cavidade Pulpar , Titânio , Níquel , Instrumentos Odontológicos , Preparo de Canal Radicular/métodos , Desenho de Equipamento
7.
Biosens Bioelectron ; 256: 116277, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38613934

RESUMO

The field of biosensing would significantly benefit from a disruptive technology enabling flexible manufacturing of uniform electrodes. Inkjet printing holds promise for this, although realizing full electrode manufacturing with this technology remains challenging. We introduce a nitrogen-doped carboxylated graphene ink (NGA-ink) compatible with commercially available printing technologies. The water-based and additive-free NGA-ink was utilized to produce fully inkjet-printed electrodes (IPEs), which demonstrated successful electrochemical detection of the important neurotransmitter dopamine. The cost-effectiveness of NGA-ink combined with a total cost per electrode of $0.10 renders it a practical solution for customized electrode manufacturing. Furthermore, the high carboxyl group content of NGA-ink (13 wt%) presents opportunities for biomolecule immobilization, paving the way for the development of advanced state-of-the-art biosensors. This study highlights the potential of NGA inkjet-printed electrodes in revolutionizing sensor technology, offering an affordable, scalable alternative to conventional electrochemical systems.


Assuntos
Técnicas Biossensoriais , Dopamina , Técnicas Eletroquímicas , Grafite , Tinta , Impressão , Técnicas Biossensoriais/instrumentação , Grafite/química , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Dopamina/análise , Eletrodos , Desenho de Equipamento , Nitrogênio/química , Humanos
8.
Biosens Bioelectron ; 256: 116260, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38613935

RESUMO

Various bioelectronic noses have been recently developed for mimicking human olfactory systems. However, achieving direct monitoring of gas-phase molecules remains a challenge for the development of bioelectronic noses due to the instability of receptor and the limitations of its surrounding microenvironment. Here, we report a MXene/hydrogel-based bioelectronic nose for the sensitive detection of liquid and gaseous hexanal, a signature odorant from spoiled food. In this study, a conducting MXene/hydrogel structure was formed on a sensor via physical adsorption. Then, canine olfactory receptor 5269-embedded nanodiscs (cfOR5269NDs) which could selectively recognize hexanal molecules were embedded in the three-dimensional (3D) MXene/hydrogel structures using glutaraldehyde as a linker. Our MXene/hydrogel-based bioelectronic nose exhibited a high selectivity and sensitivity for monitoring hexanal in both liquid and gas phases. The bioelectronic noses could sensitively detect liquid and gaseous hexanal down to 10-18 M and 6.9 ppm, and they had wide detection ranges of 10-18 - 10-6 M and 6.9-32.9 ppm, respectively. Moreover, our bioelectronic nose allowed us to monitor hexanal levels in fish and milk. In this respect, our MXene/hydrogel-based bioelectronic nose could be a practical strategy for versatile applications such as food spoilage assessments in both liquid and gaseous systems.


Assuntos
Técnicas Biossensoriais , Nariz Eletrônico , Técnicas Biossensoriais/métodos , Animais , Gases/química , Gases/análise , Aldeídos/química , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Cães , Receptores Odorantes/química , Humanos , Leite/microbiologia , Leite/química , Desenho de Equipamento , Odorantes/análise
9.
Biosens Bioelectron ; 256: 116274, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38599074

RESUMO

Exploring the photochemical (PEC) method induced by low-energy light source makes great significance to achieve high stability and accurate analysis. A sensing platform driven by near-infrared (NIR) light was designed by making the biochemically encoded carbon rich plasmonic hybrid (CPH) probe, the peptide@C-Mo2C. The inherent plasmonic effect of C-Mo2C CPH can directly absorb NIR light, thus starting effective electronic-hole pairs separation. Moreover, the photothermal effect of C-Mo2C CPH also promoted the reaction yield of photothermal catalyst reaction on sensing interface to assist the PEC signal amplification. In the presence of target trypsin, it cleaves the peptides, resulting in the release of peptide@C-Mo2C probe from interface, which leads to a relative decrease in PEC signal. More importantly, a self-calibration system consisting of two independent PEC test channels attempted to eliminate the influence of background signal and baseline drift. The test channel was used to specify the recognition target, while the blank channel was used as a reference. Therefore, the signal difference between two channels was recorded, so as to obtain results with less error and higher stability. In this NIR driven PEC sensor, the carbon rich probe with direct and efficient NIR light conversion promoted the sensitivity and a self-calibration system guaranteed the stability which provided innovative thoughts for developing ingenious PEC sensor.


Assuntos
Técnicas Biossensoriais , Carbono , Raios Infravermelhos , Carbono/química , Técnicas Eletroquímicas , Peptídeos/química , Tripsina/química , Limite de Detecção , Desenho de Equipamento
10.
Biosens Bioelectron ; 256: 116280, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38603840

RESUMO

Monitoring biomarkers in human interstitial fluids (ISF) using microneedle sensors has been extensively studied. However, most of the previous studies were limited to simple in vitro demonstrations and lacked system integration and analytical performance. Here we report a miniaturized, high-precision, fully integrated wearable electrochemical microneedle sensing device that works with a customized smartphone application to wirelessly and in real-time monitor glucose in human ISF. A microneedle array fabrication method is proposed which enables multiple individually addressable, regionally separated sensing electrodes on a single microneedle system. As a demonstration, a glucose sensor and a differential sensor are integrated in a single sensing patch. The differential sensing electrodes can eliminate common-mode interference signals, thus significantly improving the detection accuracy. The basic mechanism of microneedle penetration into the skin was analyzed using the finite element method (FEM). By optimizing the structure of the microneedle, the puncture efficiency was improved while the puncture force was reduced. The electrochemical properties, biocompatibility, and system stability of the microneedle sensing device were characterized before human application. The test results were closely correlated with the gold standard (blood). The platform can be used not only for glucose detection, but also for various ISF biomarkers, and it expands the potential of microneedle technology in wearable sensing.


Assuntos
Técnicas Biossensoriais , Desenho de Equipamento , Líquido Extracelular , Glucose , Agulhas , Dispositivos Eletrônicos Vestíveis , Humanos , Líquido Extracelular/química , Técnicas Biossensoriais/instrumentação , Glucose/análise , Smartphone , Automonitorização da Glicemia/instrumentação , 60431
12.
Proc Natl Acad Sci U S A ; 121(16): e2314359121, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38557166

RESUMO

Suction is a highly evolved biological adhesion strategy for soft-body organisms to achieve strong grasping on various objects. Biological suckers can adaptively attach to dry complex surfaces such as rocks and shells, which are extremely challenging for current artificial suction cups. Although the adaptive suction of biological suckers is believed to be the result of their soft body's mechanical deformation, some studies imply that in-sucker mucus secretion may be another critical factor in helping attach to complex surfaces, thanks to its high viscosity. Inspired by the combined action of biological suckers' soft bodies and mucus secretion, we propose a multiscale suction mechanism which successfully achieves strong adaptive suction on dry complex surfaces which are both highly curved and rough, such as a stone. The proposed multiscale suction mechanism is an organic combination of mechanical conformation and regulated water seal. Multilayer soft materials first generate a rough mechanical conformation to the substrate, reducing leaking apertures to micrometres (~10 µm). The remaining micron-sized apertures are then sealed by regulated water secretion from an artificial fluidic system based on the physical model, thereby the suction cup achieves long suction longevity on complex surfaces but minimal overflow. We discuss its physical principles and demonstrate its practical application as a robotic gripper on a wide range of complex dry surfaces. We believe the presented multiscale adaptive suction mechanism is a powerful unique adaptive suction strategy which may be instrumental in the development of versatile soft adhesion.


Assuntos
Robótica , Água , Sucção , Desenho de Equipamento
14.
Sao Paulo Med J ; 142(5): e2023224, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655983

RESUMO

BACKGROUND: There is still a debate regarding the most appropriate pleural collector model to ensure a short hospital stay and minimum complications. OBJECTIVES: To study aimed to compare the time of air leak, time to drain removal, and length of hospital stay between a standard water-seal drainage system and a pleural collector system with a unidirectional flutter valve and rigid chamber. DESIGN AND SETTING: A randomized prospective clinical trial was conducted at a high-complexity hospital in São Paulo, Brazil. METHODS: Sixty-three patients who underwent open or video-assisted thoracoscopic lung wedge resection or lobectomy were randomized into two groups, according to the drainage system used: the control group (WS), which used a conventional water-seal pleural collector, and the study group (V), which used a flutter valve device (Sinapi® Model XL1000®). Variables related to the drainage system, time of air leak, time to drain removal, and time spent in hospital were compared between the groups. RESULTS: Most patients (63%) had lung cancer. No differences were observed between the groups in the time of air leak or time spent hospitalized. The time to drain removal was slightly shorter in the V group; however, the difference was not statistically significant. Seven patients presented with surgery-related complications: five and two in the WS and V groups, respectively. CONCLUSIONS: Air leak, time to drain removal, and time spent in the hospital were similar between the groups. The system used in the V group resulted in no adverse events and was safe. REGISTRATION: RBR-85qq6jc (https://ensaiosclinicos.gov.br/rg/RBR-85qq6jc).


Assuntos
Drenagem , Tempo de Internação , Pneumonectomia , Humanos , Masculino , Feminino , Estudos Prospectivos , Pessoa de Meia-Idade , Drenagem/instrumentação , Drenagem/métodos , Pneumonectomia/instrumentação , Pneumonectomia/efeitos adversos , Pneumonectomia/métodos , Idoso , Cirurgia Torácica Vídeoassistida/métodos , Cirurgia Torácica Vídeoassistida/instrumentação , Fatores de Tempo , Resultado do Tratamento , Neoplasias Pulmonares/cirurgia , Adulto , Desenho de Equipamento , Complicações Pós-Operatórias/etiologia
15.
Sci Robot ; 9(89): eadp1956, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38657089

RESUMO

Advances in engineering enable wheeled-legged hybrid locomotion, an achievement not feasible in biological systems.


Assuntos
Biomimética , Locomoção , Robótica , Robótica/instrumentação , Humanos , Biomimética/instrumentação , Locomoção/fisiologia , Desenho de Equipamento , Animais
16.
Sci Robot ; 9(89): eadi9754, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38657092

RESUMO

Animals are much better at running than robots. The difference in performance arises in the important dimensions of agility, range, and robustness. To understand the underlying causes for this performance gap, we compare natural and artificial technologies in the five subsystems critical for running: power, frame, actuation, sensing, and control. With few exceptions, engineering technologies meet or exceed the performance of their biological counterparts. We conclude that biology's advantage over engineering arises from better integration of subsystems, and we identify four fundamental obstacles that roboticists must overcome. Toward this goal, we highlight promising research directions that have outsized potential to help future running robots achieve animal-level performance.


Assuntos
Robótica , Robótica/instrumentação , Animais , Desenho de Equipamento , Corrida/fisiologia , Fenômenos Biomecânicos , Humanos
17.
Sci Robot ; 9(89): eadp8528, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38657090

RESUMO

A smart suction cup uses haptics to supplement vision for exploration of objects in a grasping task.


Assuntos
Desenho de Equipamento , Força da Mão , Robótica , Humanos , Força da Mão/fisiologia , Robótica/instrumentação , Tato , Fenômenos Biomecânicos , Mãos/fisiologia
18.
J Neuroeng Rehabil ; 21(1): 62, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658969

RESUMO

BACKGROUND: Stroke remains a major cause of long-term adult disability in the United States, necessitating the need for effective rehabilitation strategies for post-stroke gait impairments. Despite advancements in post-stroke care, existing rehabilitation often falls short, prompting the development of devices like robots and exoskeletons. However, these technologies often lack crucial input from end-users, such as clinicians, patients, and caregivers, hindering their clinical utility. Employing a human-centered design approach can enhance the design process and address user-specific needs. OBJECTIVE: To establish a proof-of-concept of the human-centered design approach by refining the NewGait® exosuit device for post-stroke gait rehabilitation. METHODS: Using iterative design sprints, the research focused on understanding the perspectives of clinicians, stroke survivors, and caregivers. Two design sprints were conducted, including empathy interviews at the beginning of the design sprint to integrate end-users' insights. After each design sprint, the NewGait device underwent refinements based on emerging issues and recommendations. The final prototype underwent mechanical testing for durability, biomechanical simulation testing for clinical feasibility, and a system usability evaluation, where the new stroke-specific NewGait device was compared with the original NewGait device and a commercial product, Theratogs®. RESULTS: Affinity mapping from the design sprints identified crucial categories for stakeholder adoption, including fit for females, ease of donning and doffing, and usability during barefoot walking. To address these issues, a system redesign was implemented within weeks, incorporating features like a loop-backed neoprene, a novel closure mechanism for the shoulder harness, and a hook-and-loop design for the waist belt. Additional improvements included reconstructing anchors with rigid hook materials and replacing latex elastic bands with non-latex silicone-based bands for enhanced durability. Further, changes to the dorsiflexion anchor were made to allow for barefoot walking. Mechanical testing revealed a remarkable 10-fold increase in durability, enduring 500,000 cycles without notable degradation. Biomechanical simulation established the modularity of the NewGait device and indicated that it could be configured to assist or resist different muscles during walking. Usability testing indicated superior performance of the stroke-specific NewGait device, scoring 84.3 on the system usability scale compared to 62.7 for the original NewGait device and 46.9 for Theratogs. CONCLUSION: This study successfully establishes the proof-of-concept for a human-centered design approach using design sprints to rapidly develop a stroke-specific gait rehabilitation system. Future research should focus on evaluating the clinical efficacy and effectiveness of the NewGait device for post-stroke rehabilitation.


Assuntos
Desenho de Equipamento , Exoesqueleto Energizado , Transtornos Neurológicos da Marcha , Reabilitação do Acidente Vascular Cerebral , Humanos , Reabilitação do Acidente Vascular Cerebral/instrumentação , Reabilitação do Acidente Vascular Cerebral/métodos , Transtornos Neurológicos da Marcha/reabilitação , Transtornos Neurológicos da Marcha/etiologia , Design Centrado no Usuário , Feminino , Fenômenos Biomecânicos , Masculino , Pessoa de Meia-Idade , Robótica/instrumentação , Cuidadores
19.
J Biomed Opt ; 29(4): 046008, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38659998

RESUMO

Significance: Optical imaging is a non-invasive imaging technology that utilizes near-infrared light, allows for the image reconstruction of optical properties like diffuse and absorption coefficients within the tissue. A recent trend is to use signal processing techniques or new light sources and expanding its application. Aim: We aim to develop the reflective optical imaging using the chaotic correlation technology with chaotic laser and optimize the quality and spatial resolution of reflective optical imaging. Approach: Scattering medium was measured using reflective configuration in different inhomogeneous regions to evaluate the performance of the imaging system. The accuracy of the recovered optical properties was investigated. The reconstruction errors of absorption coefficients and geometric centers were analyzed, and the feature metrics of the reconstructed images were evaluated. Results: We showed how chaotic correlation technology can be utilized for information extraction and image reconstruction. This means that a higher signal-to-noise ratio and image reconstruction of inhomogeneous phantoms under different scenarios successfully were achieved. Conclusions: This work highlights that the peak values of correlation of chaotic exhibit smaller reconstruction error and better reconstruction performance in optical imaging compared with reflective optical imaging with the continuous wave laser.


Assuntos
Processamento de Imagem Assistida por Computador , Lasers , Imagem Óptica , Imagens de Fantasmas , Espalhamento de Radiação , Imagem Óptica/métodos , Processamento de Imagem Assistida por Computador/métodos , Razão Sinal-Ruído , Dinâmica não Linear , Algoritmos , Desenho de Equipamento
20.
Klin Monbl Augenheilkd ; 241(4): 347-354, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38653289

RESUMO

BACKGROUND: Various yoga positions may have an unfavorable impact on intraocular pressure (IOP) and may therefore be seen as a potential risk factor for the progression of glaucoma. The new "iCare HOME2" is a handheld self-tonometer for IOP measurements outside clinical settings. This is the first study to evaluate the immediate effect of common yoga postures on the IOP of healthy and glaucomatous eyes using the "iCare HOME2" self-tonometer and to compare the time of IOP recovery in both groups. METHODS: This is a single-center, prospective, observational study including 25 healthy and 25 glaucoma patients performing the following yoga positions: "legs up" (Viparita Karani), "bend over" (Uttanasana), "plough pose" (Halasana), and the "down face dog" (Adho Mukha Svanasana) for 90 s each, with a 2-min break in between. IOP was measured with the "iCare HOME2" before, during, and after each position. RESULTS: IOP significantly increased in all eyes in all positions (p < 0.05), showing no statistically significant difference between healthy or glaucomatous eyes (p > 0.05). The mean rise in IOP in healthy subjects was 1.6 mmHg (SD 1.42; p = 0.037), 14.4 mmHg (SD 4.48; p < 0.001), 7.5 mmHg (SD 4.21; p < 0.001), and 16.5 mmHg (SD 3.71; p < 0.001), whereas in glaucoma patients, IOP rose by 2.8 mmHg (SD 2.8; p = 0.017), 11.6 mmHg (SD 3.86; p < 0.001), 6.0 mmHg (SD 2.24; p < 0.001), and 15.1 mmHg (SD 4.44; p < 0.001) during the above listed yoga positions, repsectively. The highest increase in IOP was seen in the down face position, reaching mean IOP values above 31 mmHg in both study groups. IOP elevation was observed immediately after assuming the yoga position, with no significant change during the following 90 s of holding each pose (p > 0.05). All IOP values returned to baseline level in all individuals, with no significant difference between healthy and glaucoma participants. CONCLUSION: Our data show that common yoga positions can lead to an acute IOP elevation of up to 31 mmHg in healthy as well as glaucoma eyes, with higher IOP values during head-down positions. Given that IOP peaks are a major risk factor for glaucomatous optic neuropathy, we generally advise glaucoma patients to carefully choose their yoga exercises. If and to what extent practicing yoga leads to glaucoma progression, however, remains unclear and warrants further research.


Assuntos
Glaucoma , Pressão Intraocular , Tonometria Ocular , Yoga , Humanos , Pressão Intraocular/fisiologia , Masculino , Feminino , Tonometria Ocular/métodos , Tonometria Ocular/instrumentação , Pessoa de Meia-Idade , Glaucoma/fisiopatologia , Glaucoma/diagnóstico , Glaucoma/terapia , Reprodutibilidade dos Testes , Adulto , Desenho de Equipamento , Sensibilidade e Especificidade , Análise de Falha de Equipamento , Idoso , Estudos Prospectivos
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