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1.
Acta Orthop ; 93: 198-205, 2022 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-34984481

RESUMO

Background and purpose - Facemasks play a role in preventing the respiratory spread of SARS-CoV-2, but their impact on the physician-patient relationship in the orthopedic outpatient clinic is unclear. We investigated whether the type of surgeons' facemask impacts patients' perception of the physician-patient relationship, influences their understanding of what the surgeon said, or affects their perceived empathy. Patients and methods - All patients with an appointment in the orthopedic outpatient clinic of a tertiary university hospital during the 2-week study period were included. During consultations, all surgeons wore a non-transparent (first study week) or transparent facemask (second study week). Results of 285 of 407 eligible patients were available for analysis. The doctor-patient relationship was evaluated using the standardized Patient Reactions Assessment (PRA) and a 10-point Likert-scale questionnaire ranging from 0 (strongly disagree) to 10 (strongly agree). Results - A non-transparent facemask led to more restrictions in the physician-patient communication and a worse understanding of what the surgeon said. Patients' understanding improved with a transparent facemask with greatest improvements reported by patients aged 65 years and older (non-transparent: 6 [IQR 5-10] vs. transparent: 10 [IQR 9-10], p < 0.001) and by patients with a self-reported hearing impairment (non-transparent: 7 [IQR 3-7] vs. transparent: 9 [IQR 9-10], p < 0.001). The median PRA score was higher when surgeons wore a transparent facemask (p= 0.003). Interpretation - Surgeons' non-transparent facemasks pose a new communication barrier that can negatively affect the physician-patient relationship. While emotional factors like affectivity and empathy seem to be less affected overall, the physician-patient communication and patients' understanding of what the surgeon said seem to be negatively affected.


Assuntos
COVID-19/prevenção & controle , Desenho de Equipamento , Máscaras , Cirurgiões Ortopédicos , Pandemias/prevenção & controle , Relações Médico-Paciente , Adulto , Idoso , Estudos de Coortes , Feminino , Hospitais Universitários , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , SARS-CoV-2 , Inquéritos e Questionários
2.
J Nanobiotechnology ; 20(1): 6, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983543

RESUMO

BACKGROUND: Gold nanoparticles (AuNPs) have been widely used in local surface plasmon resonance (LSPR) immunoassays for biomolecule sensing, which is primarily based on two conventional methods: absorption spectra analysis and colorimetry. The low figure of merit (FoM) of the LSPR and high-concentration AuNP requirement restrict their limit of detection (LOD), which is approximately ng to µg mL-1 in antibody detection if there is no other signal or analyte amplification. Improvements in sensitivity have been slow in recent for a long time, and pushing the boundary of the current LOD is a great challenge of current LSPR immunoassays in biosensing. RESULTS: In this work, we developed spectral image contrast-based flow digital nanoplasmon-metry (Flow DiNM) to push the LOD boundary. Comparing the scattering image brightness of AuNPs in two neighboring wavelength bands near the LSPR peak, the peak shift signal is strongly amplified and quickly detected. Introducing digital analysis, the Flow DiNM provides an ultrahigh signal-to-noise ratio and has a lower sample volume requirement. Compared to the conventional analog LSPR immunoassay, Flow DiNM for anti-BSA detection in pure samples has an LOD as low as 1 pg mL-1 within only a 15-min detection time and 500 µL sample volume. Antibody assays against spike proteins of SARS-CoV-2 in artificial saliva that contained various proteins were also conducted to validate the detection of Flow DiNM in complicated samples. Flow DiNM shows significant discrimination in detection with an LOD of 10 pg mL-1 and a broad dynamic detection range of five orders of magnitude. CONCLUSION: Together with the quick readout time and simple operation, this work clearly demonstrated the high sensitivity and selectivity of the developed Flow DiNM in rapid antibody detection. Spectral image contrast and digital analysis further provide a new generation of LSPR immunoassay with AuNPs.


Assuntos
Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , SARS-CoV-2/isolamento & purificação , Ressonância de Plasmônio de Superfície/métodos , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Teste Sorológico para COVID-19/instrumentação , Desenho de Equipamento , Ouro/química , Humanos , Imunoensaio/instrumentação , Imunoensaio/métodos , Nanopartículas Metálicas/química , SARS-CoV-2/imunologia , Saliva/virologia , Glicoproteína da Espícula de Coronavírus/imunologia , Ressonância de Plasmônio de Superfície/instrumentação
3.
Gen Dent ; 70(1): 22-25, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34978985

RESUMO

The aim of this study was to compare the effectiveness of a reciprocating file (Reciproc) and a rotary retreatment file (Mtwo retreatment [Mtwo-R]) for the removal of filling material during root canal retreatment. A total of 30 mandibular molars with a mesial root curvature between 20° and 40° were selected and prepared using a Reciproc R25 file. The canals were filled using the lateral condensation technique and a root canal sealer. The specimens were randomly allocated into 2 groups according to the retreatment technique used (n = 15): a Reciproc R25 file or Mtwo-R 15/.05 and 25/.05 files. After retreatment, the specimens were longitudinally sectioned and photographed with an operating microscope under ×10 magnification. The percentage of total remaining filling material and the percentages in the cervical, middle, and apical thirds of the specimens were calculated. The Student t test was used for statistical comparisons of the 2 groups, and the analysis of variance followed by Tukey test was used to verify differences among the root thirds within each group. No statistically significant difference between the 2 groups was detected in the percentage of total remaining filling material (P = 0.87) or the percentage in any of the thirds of the root canals (P > 0.05) after reinstrumentation. In both groups, there was a significantly greater amount of remaining material in the apical third (P < 0.05). The results suggested that there is no difference between the 2 systems in their effectiveness at removing filling material.


Assuntos
Materiais Restauradores do Canal Radicular , Obturação do Canal Radicular , Cavidade Pulpar , Desenho de Equipamento , Guta-Percha , Humanos , Retratamento , Preparo de Canal Radicular
4.
Int Endod J ; 55(1): 124-136, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34687053

RESUMO

AIM: To evaluate the shaping ability of several heat-treated nickel-titanium systems used to prepare root canals with moderate and severe curvature, in extracted mandibular molars, by micro-computed tomography, considering their variation in kinematics and design. METHODOLOGY: Curved-mesial roots of mandibular molars were randomly selected and assigned into 4 balanced experimental groups (n = 10), established by determining homogeneous 3D parameters of volume and surface area: R-Motion (RM) size 30, 0.04 taper (RM; FKG Dentaire), Reciproc Blue (RCB) size 25, 0.08 taper (RCB; VDW GmbH), HyFlex CM (HFX) size 30, 0.04 taper (HFX; Coltène Whaledent) and XP-endo Shaper size (XPS) 30, 0.01 taper (XPS; FKG Dentaire). The volume of irrigation was established at 10 ml of 2.5% NaOCl. Throughout the entire root canal preparation procedures, the samples were fixed in a vice submerged in a container with water monitored at 37°C. Dimensional cross-sectional measures of area, perimeter, roundness, major/minor diameters and 3-dimensional (volume, surface area, structure model index - SMI) parameters as well as the smallest dentine thickness along the cervical and middle root thirds were evaluated by micro-CT. Data were analysed using analysis of variance and post hoc Tukey tests (α = 5%). RESULTS: Reciproc Blue and XPS had significantly greater mean increases in cross-sectional area measurements, only in the middle third, when compared with RM and HFX (p < .05). RM, RCB and XPS had a similar increase in measurements of length and width of perimeter (p > .05), and HFX had significantly lower mean increases in perimeter values only when compared with XPS (p < .05). RCB and XPS had significantly greater mean increases in volume when compared with RM and HFX (p < .05). RM had a significantly lower difference in SMI after preparation, compared with RCB, HFX and XPS (p < .05). The smallest dentine thickness was observed after the use of RCB (p < .05), in the danger and safety zones. CONCLUSIONS: XP-endo Shaper and RM had a shaping ability similar to that of instruments with larger tapers, achieved with less dentine removal in danger and safe zones in curved-mesial canals of extracted molar teeth treated on a laboratory benchtop.


Assuntos
Cavidade Pulpar , Preparo de Canal Radicular , Cavidade Pulpar/diagnóstico por imagem , Desenho de Equipamento , Dente Molar/diagnóstico por imagem , Dente Molar/cirurgia , Níquel , Titânio , Microtomografia por Raio-X
5.
Appl Ergon ; 98: 103588, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34562781

RESUMO

Through a randomized controlled trial, we evaluated the effects of an electro-magnetic active seat suspension that reduces exposure of a long-haul truck driver to whole body vibration (WBV) on low back pain (LBP) and disability. Among 276 drivers recruited from six trucking terminals of a major US trucking company, 135 eligible drivers were assigned to either having an Active Seat (Intervention: n = 70) - the BoseRide® electro-magnetic active seat - or Passive Seat (reference: n = 65) - a new version of their current seat (passive air suspension seat) - installed in their truck via block (terminal) randomization. Low back pain (LBP) severity, on a 0-10 scale and the Oswestry LBP Disability Index were collected before and 3-, 6-, 12-, 18-, and 24-months post seat installation. LBP severity and LBP disability scores were significantly lower post seat installation in both groups. At 3 months, LBP severity decreased -1.4 [95% CI: -2.1 to -0.7: n = 46] for drivers in the Active Seat arm, and -1.5 [95% CI: -2.3 to -0.8: n = 41] for drivers in the Passive Seat arm. In a subset of drivers, WBV exposures were collected before and after the seat installation. WBV exposures significantly decreased post seat installation for Active Seat (p < 0.01) but not for Passive Seat (p = 0.15). While the new seat-suspension technology reduced WBV exposures, LBP appeared to be improved by multiple factors. These results were limited by the secondary prevention approach and the longer-term loss to follow up due to large rates of driver turnover typical for the industry.


Assuntos
Condução de Veículo , Dor Lombar , Doenças Profissionais , Exposição Ocupacional , Desenho de Equipamento , Humanos , Dor Lombar/etiologia , Dor Lombar/prevenção & controle , Veículos Automotores , Exposição Ocupacional/efeitos adversos , Vibração/efeitos adversos
6.
Appl Ergon ; 99: 103636, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34773741

RESUMO

In this study the geometric parameter of the contact length is introduced, which intends to combine force exertion and perceived handle comfort in an anthropometric length in order to determine an optimal handle circumference. To prove suitability of the approach, 31 subjects were determined and correlations to handle circumferences with the highest finger forces and highest rated comfort were investigated. For all fingers, medium correlations were found among the contact lengths and the circumferences determined with maximum force (p < 0.001, rindex = 0.348, rmiddle = 0.419, rring = 0.374 and rlittle = 0.337) with high accordance of median values. Weak to moderate correlations were found between circumferences with maximum comfort and the contact lengths (p < 0.001, rindex = 0.150, rmiddle = 0.265, rring = 0.174). Using finger-specific proportionality factors, the contact lengths can be determined directly from the hand lengths, which enables great benefits for user-centered design.


Assuntos
Força da Mão , Design Centrado no Usuário , Desenho de Equipamento , Dedos , Mãos , Humanos
7.
Urol Clin North Am ; 49(1): 185-196, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34776051

RESUMO

Ureteral stents are an indispensable part of any (endo-) urologic practice. Despite the widely demonstrated advantages of stents, they also carry a considerable risk of side effects and complications, such as urinary symptoms, pain, hematuria, decreased quality of life, stent-related infection, and encrustation. Multiple pathways in preventing or mitigating these side effects and complications and improving stent efficacy have been and are being investigated, including stent architecture and design, biomaterials, and coatings. This article provides an update on currently researched and available stents as well as future perspectives.


Assuntos
Biofilmes , Desenho de Equipamento , Stents , Implantes Absorvíveis , Materiais Biocompatíveis , Drenagem/instrumentação , Humanos , Silicones , Stents/efeitos adversos , Ureter , Ureteroscopia/efeitos adversos
9.
Drug Deliv ; 29(1): 10-17, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34962221

RESUMO

Aerosol therapy is used to deliver medical therapeutics directly to the airways to treat respiratory conditions. A potential consequence of this form of treatment is the release of fugitive aerosols, both patient derived and medical, into the environment and the subsequent exposure of caregivers and bystanders to potential viral infections. This study examined the release of these fugitive aerosols during a standard aerosol therapy to a simulated adult patient. An aerosol holding chamber and mouthpiece were connected to a representative head model and breathing simulator. A combination of laser and Schlieren imaging was used to non-invasively visualize the release and dispersion of fugitive aerosol particles. Time-varying aerosol particle number concentrations and size distributions were measured with optical particle sizers at clinically relevant positions to the simulated patient. The influence of breathing pattern, normal and distressed, supplemental air flow, at 0.2 and 6 LPM, and the addition of a bacterial filter to the exhalation port of the mouthpiece were assessed. Images showed large quantities of fugitive aerosols emitted from the unfiltered mouthpiece. The images and particle counter data show that the addition of a bacterial filter limited the release of these fugitive aerosols, with the peak fugitive aerosol concentrations decreasing by 47.3-83.3%, depending on distance from the simulated patient. The addition of a bacterial filter to the mouthpiece significantly reduces the levels of fugitive aerosols emitted during a simulated aerosol therapy, p≤ .05, and would greatly aid in reducing healthcare worker and bystander exposure to potentially harmful fugitive aerosols.


Assuntos
Aerossóis , COVID-19 , Sistemas de Liberação de Medicamentos , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Nebulizadores e Vaporizadores , Terapia Respiratória , Aerossóis/administração & dosagem , Aerossóis/efeitos adversos , COVID-19/prevenção & controle , COVID-19/transmissão , Simulação por Computador , Sistemas de Liberação de Medicamentos/instrumentação , Sistemas de Liberação de Medicamentos/métodos , Desenho de Equipamento , Humanos , Controle de Infecções/métodos , Modelos Biológicos , Tamanho da Partícula , Terapia Respiratória/efeitos adversos , Terapia Respiratória/instrumentação , Terapia Respiratória/métodos , SARS-CoV-2
11.
J Biomech Eng ; 144(2)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34467371

RESUMO

In this work, consideration is given to an aerodynamic concept to boost the filtration in face masks of airborne hygroscopic particles such as those caused by an infected person when coughs or sneezes. Nowadays, increasing the filtration efficiency of face masks implies either increasing the number of crisscrossing fiber layers or decreasing the equivalent hydraulic diameter of the pore, however, both measures are in clear detriment of its breathability. Here, a novel strategy is proposed in which the filtration of an airborne particle is boosted by increasing its diameter. We called properly this concept as the aerodynamic barrier layer. In this concept, a traditional crisscrossing fiber layer is replaced by a parallel rearranged of the fibers in the direction of the flow. This rearrangement will promote central lift forces which will push the particles toward the center of the channel where after clustering they will coalesce resulting in a bigger particle that can be now easily captured by a conventional fiber crisscrossing layer. Utilizing a simplified geometrical model, an expression for the required length of the aerodynamic barrier layer was derived. It is shown that an aerodynamic barrier layer with a length of only a few millimeters can aerodynamically focus water droplets around 1 µm-diameter and the penetration of airborne particles can be reduced up to 55%.


Assuntos
Filtração/instrumentação , Máscaras , Material Particulado/isolamento & purificação , Desenho de Equipamento , Tamanho da Partícula
12.
Ultrasonics ; 119: 106600, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34627028

RESUMO

High quality tissue-mimicking phantoms (TMPs) have a critical role in the preclinical testing of emerging modalities for diagnosis and therapy. TMPs capable of accurately mimicking real tissue in Magnetic Resonance guided Focused Ultrasound (MRgFUS) applications should be fabricated with precise T1 and T2 relaxation times. Given the current popularity of the MRgFUS technology, we herein performed a systematic review on the MR relaxation properties of different phantoms types. Polyacrylamide (PAA) and agar based phantoms were proven capable of accurately replicating critical thermal, acoustical, and MR relaxation properties of various body tissues. Although gelatin phantoms were also proven factional in this regard, they lack the capacity to withstand ablation temperatures, and thus, are only recommended for hyperthermia applications. Other gelling agents identified in the literature are Poly-vinyl alcohol (PVA), Polyvinyl Chloride (PVC), silicone, and TX-150/ TX-151; however, their efficacy in thermal studies is yet to be established. PAA gels are favorable in that they offer optical transparency enabling direct visualization of coagulative lesions. On the other hand, agar phantoms have lower preparation costs and were proven very promising for use with the MRgFUS technology, without the toxicity issues related to the preparation and storage of PAA materials. Remarkably, agar turned out to be the prominent modifier of the T2 relaxation time even for phantoms containing other types of gelling agents instead of agar. This review could be useful in manufacturing realistic MRgFUS phantoms while simultaneously indicating an opportunity for further research in the field with a particular focus on the MR behavior of agar-based TMPs.


Assuntos
Ágar/química , Materiais Biomiméticos/química , Imageamento por Ressonância Magnética/métodos , Imagens de Fantasmas , Desenho de Equipamento , Temperatura
13.
Ultrasonics ; 118: 106580, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34555738

RESUMO

Recently, a method for estimating three-dimensional acoustic impedance profiles in cultured cells and human dermal organs was proposed by interpreting the reflected ultrasonic signal based on a 1-D transmission line model for acoustic impedance microscopy (AIM). However, AIM has a disadvantage that reflected signals from cells overlap with that from a reference substrate. Additionally, the amplitudes of the reflected signals from the specimens are significantly weaker than that from the substrate. In this paper, we proposed a new method for separation of those signals based on a concept of clutter filter, which had been developed for a color Doppler method in medical ultrasonic imaging. The proposed filter using singular value decomposition (SVD) could separate original signals into desired signals such as those from the substrate and cells. Additionally, an effect from a tilt of the substrate was investigated in this study. Separability of the proposed filter was evaluated by two investigations. First one was to evaluate the separability by estimating a correlation coefficient between the filtered signal and signal reflected from a position only with the substrate. Second one was to compare a slope of the substrate estimated from the original signal with that estimated from the filtered signals from the substrate. The experimental results showed that the proposed filter could separate signals from the substrate, and the compensation of the tilt of the substrate could improve the performance of the proposed filter.


Assuntos
Astrócitos/ultraestrutura , Células Cultivadas/ultraestrutura , Microscopia Acústica/instrumentação , Animais , Desenho de Equipamento , Ratos , Processamento de Sinais Assistido por Computador
14.
Br J Radiol ; 95(1129): 20210835, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34672690

RESUMO

OBJECTIVE: To evaluate the efficacy of a barrier shield in reducing droplet transmission and its effect on image quality and radiation dose in an interventional suite. METHODS: A human cough droplet visualisation model in a supine position was developed to assess efficacy of barrier shield in reducing environmental contamination. Its effect on image quality (resolution and contrast) was evaluated via image quality test phantom. Changes in the radiation dose to patient post-shield utilisation was measured. RESULTS: Use of the shield prevented escape of visible fluorescent cough droplets from the containment area. No subjective change in line-pair resolution was observed. No significant difference in contrast-to-noise ratio was measured. Radiation dosage to patient was increased; this is predominantly attributed to the increased air gap and not the physical properties of the shield. CONCLUSION: Use of the barrier shield provided an effective added layer of personal protection in the interventional radiology theatre for aerosol generating procedures. ADVANCES IN KNOWLEDGE: This is the first time a human supine cough droplet visualisation has been developed. While multiple types of barrier shields have been described, this is the first systematic practical evaluation of a barrier shield designed for use in the interventional radiology theatre.


Assuntos
Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Equipamentos de Proteção , Radiologia Intervencionista/instrumentação , Adulto , COVID-19/transmissão , Tosse , Desenho de Equipamento , Fluorescência , Humanos , Masculino , Imagens de Fantasmas , Doses de Radiação , Razão Sinal-Ruído , Decúbito Dorsal
15.
Ultrasonics ; 120: 106658, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34922218

RESUMO

High-intensity focused ultrasound (HIFU) has been successfully used as a minimally invasive cancer therapy method. For monitoring the therapy, the amplitude-modulated (AM) localized motion imaging (LMI) method had been proposed. This paper compares the performance of AM-LMI while using different sine modulating wave frequencies and proposes the utilization of square modulating waves to gain the advantages of both high and low modulating frequencies. A single element therapy transducer with a 2 MHz central frequency was driven by sine modulating waves with different frequencies (approximate 34, 67, 102, 168, and 201 Hz) and by square modulating waves with two frequencies (34 and 67 Hz). An imaging probe with a 5 MHz central frequency and a 20 MHz sampling frequency was mounted in the center hole of the therapy transducer to acquire pulse-echo data, which were used to estimate the tissue oscillation amplitude induced by the acoustic radiation force of the HIFU beam. The decrease ratio of the oscillation amount was then utilized to estimate the coagulated lesion length during the therapy. The comparison of modulating frequencies demonstrated that a higher frequency could bring higher sensitivity to small lesions, while a lower frequency not only gives greater noise robustness but also promotes the ability to estimate lengths of larger lesions. The utilization of a square modulating wave demonstrated its utility to produce tissue oscillation with multiple frequencies and gain the advantages of both high and low modulating frequencies.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Fígado/diagnóstico por imagem , Fígado/cirurgia , Animais , Módulo de Elasticidade , Desenho de Equipamento , Movimento (Física) , Suínos , Transdutores
16.
PLoS One ; 16(12): e0261593, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34936685

RESUMO

To realize real-time and accurate performance monitoring of large- and medium-sized seed metering devices, a performance monitoring system was designed for seed metering devices based on LED visible photoelectric sensing technology and a pulse width recognition algorithm. Through an analysis of the of sensing component pointing characteristics and seed motion characteristics, the layout of the sensing components and critical photoelectric sensing system components was optimized. Single-grain seed metering devices were employed as monitoring objects, and the pulse width thresholds for Ekangmian-10 cotton seeds and Zhengdan-958 corn seeds were determined through pulse width threshold calibration experiments employed at different seed metering plate rotational speeds. According to the seeding quantity monitoring experiments, when the seed metering plate rotational speed ranged from 28.31~35.71 rev/min, the accuracy reached 98.41% for Ekangmian-10 cotton seeds. When the seed metering plate rotational speed ranged from 13.78~19.39 rev/min, the seeding quantity monitoring accuracy reached 98.19% for Zhengdan-958 corn seeds. Performance monitoring experiments revealed that the qualified seeding quantity monitoring accuracy of cotton precision seed metering devices, missed seeding quantity monitoring accuracy, and reseeding quantity monitoring accuracy could reach 98.75%, 94.06%, and 91.30%, respectively, within a seeding speed range of 8~9 km/h. This system meets the requirements of real-time performance monitoring of large- and medium-sized precision seed metering devices, which helps to improve the operational performance of seeding machines.


Assuntos
Produção Agrícola , Sementes/crescimento & desenvolvimento , Zea mays/crescimento & desenvolvimento , Algoritmos , Produção Agrícola/instrumentação , Desenho de Equipamento , Sementes/anatomia & histologia , Zea mays/anatomia & histologia
17.
PLoS One ; 16(12): e0261933, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34962969

RESUMO

Virtual reality (VR) technology plays a significant role in many biomedical applications. These VR scenarios increase the valuable experience of tasks requiring great accuracy with human subjects. Unfortunately, commercial VR controllers have large positioning errors in a micro-manipulation task. Here, we propose a VR-based framework along with a sensor fusion algorithm to improve the microposition tracking performance of a microsurgical tool. To the best of our knowledge, this is the first application of Kalman filter in a millimeter scale VR environment, by using the position data between the VR controller and an inertial measuring device. This study builds and tests two cases: (1) without sensor fusion tracking and (2) location tracking with active sensor fusion. The static and dynamic experiments demonstrate that the Kalman filter can provide greater precision during micro-manipulation in small scale VR scenarios.


Assuntos
Sistemas Homem-Máquina , Interface Usuário-Computador , Realidade Virtual , Adulto , Algoritmos , Computadores , Desenho de Equipamento , Feminino , Humanos , Masculino , Micromanipulação , Movimento , Reprodutibilidade dos Testes , Software
18.
PLoS One ; 16(12): e0261623, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34972133

RESUMO

Since being introduced into clinical practice the AFX family of endografts has undergone labelling updates, design and manufacturing changes to address a Type III failure mode. The published literature on the performance of the current endograft-AFX2 -is limited to small series with limited follow up. The present study reports the largest series of patients implanted with AFX2 for the treatment of abdominal aortic aneurysms. The study was a retrospective, 5 center study of patients receiving an AFX2 endograft from January 2016 until Dec 2020. Electronic case report forms were provided to four of the centers, with one additional site providing relevant outcomes in an independent dataset. Relevant outcomes were reported via Kaplan-Meier analysis and included all-cause mortality, aneurysm-related mortality, post EVAR aortic rupture, open conversion, device related reinterventions and endoleaks. Among a cohort of 460 patients, 405 underwent elective repair of an AAA, 50 were treated for a ruptured AAA, and 5 were aorto-iliac occlusive disease cases. For the elective cohort (mean age 73.7y, 77% male, mean AAA diameter 5.4cm), the peri-operative mortality was 1.7%. Freedom from aneurysm-related mortality was 98.2% at 1,2,3 and 4 years post-operatively, there were no post-operative aortic ruptures, and 2 patients required open conversion. Freedom from Type Ia endoleaks was 99.4% at 1, 2, 3 and 4 years. Freedom from Type IIIa and Type IIIb endoleaks were 100% and 100% (year 1), 100% and 99.6% (year 2), 99.4% and 99.6% (year 3), 99.4% and 99.6% (year 4) respectively. Freedom from all device-related reintervention (including Type II endoleaks) at 4 y was 86.8%. The AFX2 endograft appears to perform to a satisfactory standard in terms of patient centric outcomes in mid-term follow up. The Type Ia and Type III endoleaks rates at 4y appear to be within acceptable limits. Further follow up studies are warranted.


Assuntos
Aneurisma da Aorta Abdominal/fisiopatologia , Procedimentos Endovasculares , Enxerto Vascular , Idoso , Aneurisma Roto , Endoleak , Desenho de Equipamento , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Assistência Centrada no Paciente , Período Pós-Operatório , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
19.
Artigo em Inglês | MEDLINE | ID: mdl-34948732

RESUMO

This cross-sectional study aimed to examine the oral hygiene behaviors in the general population and identify factors affecting oral hygiene behaviors and plaque removal efficacy. A survey was distributed to patients through 11 dental practices in Japan, and each patient's plaque index score (PIS) was recorded. In total, 1184 patients participated (521 women and 660 men), with 84.04% using manual toothbrushes (MTBs) and 15.96% using electric toothbrushes (ETBs). ETB users had a significantly lower PIS compared to MTB users (p = 0.0017). In addition, a statistically significant difference in the PIS was detected in relation to the frequency of brushing per day (≥2 times) and time spent on brushing (≥1 min). Some MTB users spent less than 1 min brushing, while all ETB users spent at least 1 min brushing, and extended brushing periods significantly improved the PIS for the MTB users. MTB users tend to replace brush heads more frequently than ETB users, and the frequency of replacement affected the PIS significantly (p < 0.01) for the MTB users. The status of dental treatment (first visit, in treatment versus recall) also significantly affected the PIS (p < 0.01). The ETB was more effective than the MTB in terms of better plaque removal and reduced frequency of brush head replacement.


Assuntos
Higiene Bucal , Escovação Dentária , Estudos Transversais , Eletricidade , Desenho de Equipamento , Feminino , Humanos , Japão , Masculino , Método Simples-Cego
20.
Cells ; 10(12)2021 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-34943846

RESUMO

The aim of the work was to design and construct a microscopic stage that enables the observation of biological cells in a magnetic field with a constant magnetic force. Regarding the requirements for biological observations in the magnetic field, construction was based on the standard automatic stage of an optical microscope ZEISS Axio Observer, and the main challenge was to design a set of magnets which were the source of a field in which the magnetic force was constant in the observation zone. Another challenge was to design a magnet arrangement producing a weak magnetic field to manipulate the cells without harming them. The Halbach array of magnets was constructed using permanent cubic neodymium magnets mounted on a 3D printed polymer ring. Four sets of magnets were used, differing in their dimensions, namely, 20, 15, 12, and 10 mm. The polymer rings were designed to resist magnetic forces and to keep their shape undisturbed when working under biological conditions. To check the usability of the constructs, experiments with magnetic microparticles were executed. Magnetic microparticles were placed under the microscope and their movement was observed to find the acting magnetic force.


Assuntos
Campos Magnéticos , Magnetismo/instrumentação , Sobrevivência Celular , Desenho de Equipamento , Imageamento Tridimensional , Impressão Tridimensional , Reprodutibilidade dos Testes , Temperatura
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