Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
1.
Sensors (Basel) ; 24(2)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38257585

RESUMO

This paper proposes a method for generating dynamic virtual fixtures with real-time 3D image feedback to facilitate human-robot collaboration in medical robotics. Seamless shared control in a dynamic environment, like that of a surgical field, remains challenging despite extensive research on collaborative control and planning. To address this problem, our method dynamically creates virtual fixtures to guide the manipulation of a trocar-placing robot arm using the force field generated by point cloud data from an RGB-D camera. Additionally, the "view scope" concept selectively determines the region for computational points, thereby reducing computational load. In a phantom experiment for robot-assisted port incision in minimally invasive thoracic surgery, our method demonstrates substantially improved accuracy for port placement, reducing error and completion time by 50% (p=1.06×10-2) and 35% (p=3.23×10-2), respectively. These results suggest that our proposed approach is promising in improving surgical human-robot collaboration.


Assuntos
Robótica , Cirurgia Torácica , Humanos , Retroalimentação , Procedimentos Cirúrgicos Minimamente Invasivos , Imagens de Fantasmas
2.
Environ Sci Technol ; 57(16): 6360-6372, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37036108

RESUMO

Residential buildings provide unique conditions for opportunistic premise plumbing pathogen (OPPP) exposure via aerosolized water droplets produced by showerheads, faucets, and tubs. The objective of this review was to critically evaluate the existing literature that assessed the impact of potentially enhancing conditions to OPPP occurrence associated with residential plumbing and to point out knowledge gaps. Comprehensive studies on the topic were found to be lacking. Major knowledge gaps identified include the assessment of OPPP growth in the residential plumbing, from building entry to fixtures, and evaluation of the extent of the impact of typical residential plumbing design (e.g., trunk and branch and manifold), components (e.g., valves and fixtures), water heater types and temperature setting of operation, and common pipe materials (copper, PEX, and PVC/CPVC). In addition, impacts of the current plumbing code requirements on OPPP responses have not been assessed by any study and a lack of guidelines for OPPP risk management in residences was identified. Finally, the research required to expand knowledge on OPPP amplification in residences was discussed.


Assuntos
Água Potável , Engenharia Sanitária , Abastecimento de Água , Habitação , Microbiologia da Água
3.
J Appl Clin Med Phys ; 24(7): e13973, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36972299

RESUMO

PURPOSE: Proton treatment plan perturbation by common dental fixtures such as amalgams (Am) and porcelain-fused-to-metal (PFM) crowns has, to date, been uncharacterized. Previous studies have been conducted to determine the physical effect of these materials within the beam path for single spots, but their effects on complex treatment plans and clinical anatomy have not yet been quantified. The present manuscript aims to study the effect of Am and PFM fixtures on proton treatment planning in a clinical setting. METHODS: An anthropomorphic phantom with removable tongue, maxilla, and mandible modules was simulated on a clinical computed tomography (CT) scanner. Spare maxilla modules were modified to include either a 1.5 mm depth central groove occlusal amalgam (Am) or a porcelain-fused-to-metal (PFM) crown, implanted on the first right molar. Modified tongue modules were 3D printed to accommodate several axial or sagittal oriented pieces of EBT-3 film. Clinically representative spot-scanning proton plans were generated in Eclipse v.15.6 using the proton convolution superposition (PCS) algorithm v.15.6.06 using a multi-field optimization (MFO) technique with the goal of delivering a uniform 54 Gy dose to a clinical target volume (CTV) typical of a base-of-tongue (BoT) treatment. A typical geometric beam arrangement of two anterior oblique (AO) beams and a posterior beam was employed. Plans optimized without any material overrides were delivered to the phantom A) without implants; B) with Am fixture; or C) with PFM crown. Plans were also reoptimized and delivered with inclusion of material overrides to equate relative stopping power of the fixture with that of a previously measured result. RESULTS: Plans exhibit slightly greater dose weight towards AO beams. The optimizer accounted for inclusion of fixture overrides by increasing beam weights to the beam closest to the implant. Film measurements exhibited cold spots directly within the beam path through the fixture in plans with and without overridden materials. Cold spots were somewhat mitigated in plans including overridden materials in the structure set but were not entirely eliminated. Cold spots associated with Am and PFM fixtures were quantified at 17% and 14% for plans without overrides, respectively, and 11% and 9% with using Monte Carlo simulation. Compared with film measurements and Monte Carlo simulation, the treatment planning system underestimates the dose shadowing effect in plans including material overrides. CONCLUSIONS: Dental fixtures create a dose shadowing effect directly in line with the beam path through the material. This cold spot is partially mitigated by overriding the material to measured relative stopping powers. Due to uncertainties in modeling perturbation through the fixture, the magnitude of the cold spot is underestimated using the institutional TPS when compared to measurement and MC simulation.


Assuntos
Terapia com Prótons , Radioterapia de Intensidade Modulada , Humanos , Terapia com Prótons/métodos , Prótons , Dosagem Radioterapêutica , Porcelana Dentária , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Método de Monte Carlo
4.
Scand J Med Sci Sports ; 32 Suppl 1: 127-139, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33373070

RESUMO

This study analyzed the impact of performing four consecutive football matches separated by 48-72 hours during a FIFA tournament on physical load, technical performance and plasma markers of redox state, muscle damage and inflammation in elite female players. Forty-eight players from three national teams were evaluated at seven time points: before (baseline) and throughout the tournament (after each match and before two training sessions). Only data from players who played all matches were included in the analyses (N = 13). The players were divided into high-rank (N = 6) and low-rank (N = 7) team players according to FIFA standards. Plasma creatine kinase (CK), C-reactive protein (CRP), total antioxidant status (TAS), and uric acid (UA) were analyzed at the selected time points. Technical performance and physical load were also quantified according to team rank. Players from low-rank teams played significantly more time than high-rank players (85 ± 10 vs 67 ± 15 minutes; P = .02; d = 1.51). Low-rank team players presented higher values in technical performance actions than the high-rank team players, but most of the differences were explained by the longer match time played. UA content differed across the matches, increasing from baseline (F(4,40)  = 3.90; P = .01) and more in the high-rank team players (F(1,10)  = 20.46; P = .001), while CRP only differed across the matches (F(4,36)  = 2.66; P = .05), also increasing from baseline. A large time effect was shown for UA only in the high-rank players (η2 p  = 0.50; P = .02). Four consecutive matches did not result in considerable alterations in plasma stress markers, physical load, and technical performance in elite female football players from distinct rank levels.


Assuntos
Desempenho Atlético , Futebol , Feminino , Humanos , Desempenho Atlético/fisiologia , Biomarcadores , Proteína C-Reativa , Creatina Quinase , Futebol/fisiologia
5.
J Sports Sci ; 40(7): 783-796, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34955079

RESUMO

Intensified periods of competition are common in many team sports, potentially leading to increased fatigue and reduced performance. The purpose of this study was to investigate the effect of repeated high-intensity sprint interval exercise on cognitive function, mood and perceptions of energy and fatigue. Twenty-four trained rugby players completed multiple bouts of repeated sprints across two consecutive days. Prior to and following each set of maximal effort sprints or equivalent control duration, a battery of cognitive tasks assessing simple and choice reaction time, visuo-spatial working memory and inhibition were completed as well as visual analogue scales that assessed mood, energy, and fatigue. Accuracy of incongruent Stroop responses was significantly lower across day 2 compared to day 1 and the control condition. Four-choice reaction time was slower across day 2 whilst feelings of alertness, contentedness, and physical and mental energy were reduced while ratings of physical and mental fatigue increased. These findings suggest that intensified periods of high-intensity sprint interval exercise have detrimental effects on executive function, mood and perceptions of physical and mental energy, and fatigue. These deleterious effects have the potential to impact performance and may increase the propensity for injury/accidents in certain sporting and non-sporting contexts.


Assuntos
Desempenho Atlético , Esportes , Desempenho Atlético/fisiologia , Cognição , Função Executiva , Exercício Físico , Humanos , Masculino , Esportes de Equipe
6.
J Biol Regul Homeost Agents ; 34(1 Suppl. 2): 13-17. DENTAL SUPPLEMENT, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32270663

RESUMO

Oral rehabilitation by means dental implants has high standards of success. Recently, a new type of two-pieces spiral implants has been introduced in the market. Since few reports focus of the efficacy of this medical device as a reliable tool for oral rehabilitation, here a retrospective study is reported. In the period June-December 2017 one hundred and two spiral fixtures were inserted, half in females and 51 in males. The median age was 56 ± 8 (min-max 36-73 years). Forty-eight implants were inserted in upper jawbone and 54 in mandible. Two implants were lost and thus survival rate (SVR) is 99.9%. Then peri-implant bone resorption was used to investigate the clinical success (success rate, SCR) over time. No implants have a crestal bone resorption greater than 1.5 mm in the first year follow up. No studied variable has an effect on clinical outcome. In conclusion the studied implants have high SCR and SVR so that they are good tools for oral rehabilitation.


Assuntos
Perda do Osso Alveolar , Implantes Dentários , Mandíbula/cirurgia , Maxila/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
7.
J Biol Regul Homeost Agents ; 34(6 Suppl. 3): 47-57, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33412780

RESUMO

The systematic analysis of parameters impacting implant primary stability is difficult to achieve with human cadavers or animal models, particularly for complex trans-sinus procedures to determine the effects of cortical layers and bone engagement on implant stability before and after a simulated load in vitro. Solid rigid polyurethane blocks, partially intersected by an 8-mm-thick space, were created to imitate tri-cortical situations, the presence of the sinus cavity, and the posterior maxilla with different degrees of bone atrophy. Implants were inserted through the cavity at an angle of 30˚ (scenarios 1 and 2) to imitate the clinical protocol. Controls simulating uni-cortical anchorage and no sinus cavity were also included (controls 1 and 2). Four parameters were measured: peak insertion torque, insertion work, resistance to lateral bending loads and extraction torque. Scenarios 1 and 2 displayed similar peak insertion torque to control 2, where all three groups anchored equal amounts of bone surrogate. The distribution of surrogate bone in contact with trans-cavity implants influenced both extraction torque and the degree of lateral bending. Sufficient peak insertion torque can be attained with a trans-sinus tricortical implant anchorage providing sufficient apical and coronal bone is engaged.


Assuntos
Osso Cortical , Implantes Dentários , Humanos , Maxila/cirurgia , Poliuretanos , Próteses e Implantes , Torque
8.
Asian-Australas J Anim Sci ; 32(3): 452-458, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30840791

RESUMO

OBJECTIVE: The study was carried to determine the interaction effects of pen enrichment and sex on behavioral activities, skin lesions and physiology of Windsnyer pigs. METHODS: Forty-eight growing Windsnyer pigs of both sex, with an average initial body weight of 21.6 (±9.01) kg were used. Four pigs were randomly assigned to either enriched or barren pens at a stocking density of 0.35 m2/pig. Enriched pens contained 2 L bottles filled with stones and suspended at head level on ropes stretching across the pens. In addition, two plastic balls (90 mm in diameter) and 500 mL bottles (235 mm long) were placed on the floor of each enriched pen. RESULTS: Pigs in barren environments had higher heart rates (p<0.001) than those in enriched pens. There was an interaction of pen environment and sex on rectal temperature (p<0.001). Females in enriched pens had higher rectal temperatures (p<0.05) than females in barren pens. There was no interaction of pen environment and sex on time spent eating and drinking (p>0.05). Time spent bullying was influenced (p<0.05) by pen environment and sex. Female pigs in barren environment spent more time on bullying than females in enriched pens. There was an interaction of pen environment and sex on time spent lying down and walking (p<0.05). Female pigs in enriched pens spent more time lying down than females in barren pens. Males in barren pens spent more time walking than males in enriched pens while no effect of pen environment was observed in females. There was an interaction of pen environment and sex on the number of skin lesions in the head, neck and shoulder region and other parts of the body (p<0.05). CONCLUSION: It was concluded that pen enrichment reduced the number of skin lesions and anti-social behaviors, especially for female pigs. There is a need, therefore of housing indigenous pigs under confinement.

9.
J Sports Sci ; 36(5): 585-591, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28498791

RESUMO

This study investigated the effects of successive matches on match-running in elite under-23 soccer players during an international tournament. Match-running data was collected using a semi-automated multi-camera tracking system during an international under-23 tournament from all participating outfield players. Players who played 100% of all group stage matches were included (3 matches separated by 72 h, n = 44). Differences in match-running performance between matches were identified using a generalised linear mixed model. There were no clear effects for total, walking, jogging, running, high-speed running and sprinting distance between matches 1 and 3 (effect size (ES); -0.32 to 0.05). Positional analysis found that sprint distance was largely maintained from matches 1 to 3 across all positions. Attackers had a moderate decrease in total, jogging and running distance between matches 1 and 3 (ES; -0.72 to -0.66). Classifying players as increasers or decreasers in match-running revealed that match-running changes are susceptible to individual differences. Sprint performance appears to be maintained over successive matches regardless of playing position. However, reductions in other match-running categories vary between positions. Changes in match-running over successive matches affect individuals differently; thus, players should be monitored on an individual basis.


Assuntos
Desempenho Atlético/fisiologia , Comportamento Competitivo/fisiologia , Corrida/fisiologia , Futebol/fisiologia , Humanos , Masculino , Estudos de Tempo e Movimento , Adulto Jovem
10.
Heliyon ; 10(3): e25104, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38318023

RESUMO

Historically, approaches for determining peak water demand in buildings have been based on probabilistic methods. Extensive research has shown that these methods lack accuracy because of the human factor in the probability of use. Inaccuracy in the calculation of peak water demand is the main cause of oversized water supply systems in buildings. This has led to unfavorable effects such as: 1) increasing the building carbon footprint due to the use of more construction materials, and 2) engendering health hazards due to the stagnation of water causing microbial growing. This paper presents a step-by-step methodology that serves to calculate the peak water demand by simulating the use of plumbing fixtures based on data obtained from standardized flowrate. With the implementation of the methodology, the peak water demand estimated was 2.6 times lower in comparison to traditional methods. The main conclusion drawn from the research is the potential of the methodology to easily simulated peak water demand in residential buildings in the short term. Thus, it reveals a hotspot for peak water demand calculation and can serve as routes for future research.

11.
Artigo em Inglês | MEDLINE | ID: mdl-37547946

RESUMO

To verify the advantages of Virtual Fixtures (VFs) by comparing the result of guide plate navigation (GPN) and VFs in robot-assisted osteotomy. Robot-assisted surgery has been extensively applied in traditional orthopedic surgeries. It fundamentally improves surgeries' cutting accuracy. In addition, many key techniques have been applied in bone cutting to increase the procedure's safety in various ways. In this paper, two robot-assisted osteotomy methods are proposed. Three operators with no osteotomy experience performed plane cutting with the assistance of a robot. GPN and VFs were applied to assist the Sawbones cutting. Each operator has five attempts using each method to perform bone cutting, distance errors and angular errors were recorded. The advantage of Sawbones is that there is no influence from soft tissues and blood. It can give a more precise measurement. The results show that both methods have high accuracy with the robot's assistance. VFs have higher accuracy in comparison with GPN. With GPN, the mean distance and angular error of the three operators were 2.974 ± 0.282 mm and 4.737 ± 0.254°. With VFs, the mean range and angular error of the three operators were 1.857 ± 0.349 mm and 2.24 ± 0.123°, respectively. VFs limited the robot's end in the planned area, increasing the accuracy and safety of robot-assisted osteotomy.

12.
Int J Comput Assist Radiol Surg ; 18(11): 1969-1976, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37454325

RESUMO

PURPOSE: In bone surgery specialties, like orthopedics, neurosurgery, and oral and maxillofacial surgery patient safety and treatment success depends on the accurate implementation of computer-based surgical plans. Unintentional plan deviations can result in long-term functional damage to the patient. With on-site teleoperation, the surgeon operates a slave robot with a physically-decoupled master device, while being directly present at the operation site. This allows the surgeon to perform surgical tasks with robotic accuracy, while always remaining in the control loop. METHODS: In this study the master- and slave-side accuracy of an on-site teleoperated miniature cooperative robot (minaroHD) is evaluated. Master-side accuracy is investigated in a user study regarding scale factor, target feed rate, movement direction and haptic guidance stiffness. Scale factors are chosen to correspond to primarily finger, hand, and arm movements. Slave-side accuracy is investigated in autonomous milling trials regarding stepover, feed rate, movement direction, and material density. RESULTS: Master-side user input errors increase with increasing target feed rate and scale factor, and decrease with increasing haptic guidance stiffness. Resulting slave-side errors decrease with increasing scale factor and are < 0.07 mm for optimal guidance parameters. Slave-side robot position errors correlate with the feed rate but show little correlation with stepover distance. For optimal milling parameters, the 95th percentile of tracked slave-side position error is 0.086 mm with a maximal error of 0.16 mm. CONCLUSION: For optimal guidance and milling parameters, the combined error of 0.23 mm is in the range of the dura mater thickness (< 0.27 mm) or mandibular canal wall (~ 0.85 mm). This corresponds to safety margins in high-demand surgical procedures like craniotomies, laminectomies, or decortication of the jaw. However, for further clinical translation, the performance and usability of on-site teleoperated milling must be further evaluated for real-life clinical application examples with consideration of all error sources in a computer-assisted surgery workflow.

13.
Int J Sports Physiol Perform ; 18(9): 901-908, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36410336

RESUMO

PURPOSE: To examine the effect of match schedule on self-reported wellness and sleep in rugby union referees during the 2019 Rugby World Cup. METHODS: Following an observational design, 18 international-level male referees participating in the 2019 Rugby World Cup completed a daily questionnaire to quantify wellness status (sleep quality, mood, stress, fatigue, muscle soreness, and total wellness) and sleep characteristics (bedtime, wake-up time, and time in bed) from the previous night across the tournament. Linear mixed models and effect sizes (Hedges gav) assessed differences in wellness and sleep characteristics between prematch and postmatch days surrounding single-game and 2-game congested match schedules (prematch1, postmatch1, prematch2, and postmatch2 days). RESULTS: During regular schedules, all self-reported wellness variables except stress were reduced (gav = 0.33-1.05, mean difference -0.32 to -1.21 arbitrary units [AU]) and referees went to bed later (1.08, 1:07 h:min) and spent less time in bed (-0.78, 00:55 h:min) postmatch compared with prematch days. During congested schedules, only wellness variables differed across days, with total wellness reduced on postmatch1 (-0.88, -3.56 AU) and postmatch2 (-0.67, -2.70 AU) days, as well as mood (-1.01, -0.56 AU) and fatigue (-0.90, -1.11 AU) reduced on postmatch1 days compared with prematch days. CONCLUSION: Referees were susceptible to acute reductions in wellness on days following matches regardless of schedule. However, only single-game regular match schedules negatively impacted the sleep characteristics of referees. Targeted strategies to maximize wellness status and sleep opportunities in referees considering the match schedule faced should be explored during future Rugby World Cup competitions.


Assuntos
Rugby , Humanos , Masculino , Fadiga , Autorrelato , Sono
14.
J Mech Behav Biomed Mater ; 146: 106063, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37556925

RESUMO

Skull reconstruction using cranial implants is often required for repairing skull defects caused due to trauma, diseases, or malignancy to protect intracranial structures. For relieving Intracranial Pressure (ICP) surgeons restore cranial defects either using natural bones or fabricated custom cranial implants. With the increase in Traumatic Brain Injuries (TBI) and challenges faced by TBI patients to regain normalcy, it is imperative to analyse the mechanical behaviour of skull-implant assemblies under some Head Injury Criteria (HIC). Medical grade materials including Titanium Alloys (Ti-6Al-4V) and Polyether-ether-ketone (PEEK) are used by fabricating Patient-Specific Implants (PSI) manufactured using 3D imaging, modelling and printing techniques. 3D technologies are preferred over conventional manufacturing methods, as they enable fabrication of custom shapes, sizes and properties for these PSI. For an effective attachment of PSI with a defective skull, a stable joint and plate arrangement as fixture plates is necessary at their interface. These fixtures can have variable numbers, design shapes, materials and location arrangements. This paper presents the Finite Element Method/Analysis (FEM/FEA) study of PSI attached to a defected skull for reconstruction, with linear shaped fixture configuration, when subjected to an external dynamic loading at 5 m/s, strain rate of 10s-1 to 243s-1 and ICP of 15mm Hg from three sides of the skull faces. Three different materials as Neoprene (soft), Concrete (medium rigid) and E-Glass (highly rigid) have been used, in the form of a rectangular thin cuboidal wall structure, at an angle of 45° with the skull face. Four linear shaped fixture plates which were simplest to design, were used to attach the PSI-skull assembly, to ensure that weight of the PSI-fixation assembly on the patient remains minimal, overall assembly has symmetrical fixations and efforts required by a surgeon for fitment of these plates remain minimal. Placement of these fixture plates has been optimized to encompass the complete PSI-skull interface section, due to which the stresses within all the assembly components (PSI, fixture plate and skull) reduced by nearly 2.5 times than the initial design and remained within yielding limits, thereby, averting any failure under heavy external dynamic loading.


Assuntos
Crânio , Titânio , Humanos , Titânio/química , Crânio/cirurgia , Polímeros , Polietilenoglicóis/química , Cetonas/química , Análise de Elementos Finitos , Estresse Mecânico
15.
Math Biosci Eng ; 20(12): 21032-21048, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38124586

RESUMO

Pad printing is used in automotive, medical, electrical and other industries, employing diverse materials to transfer a 2D image onto a 3D object with different sizes and geometries. This work presents a universal fixation system for pad printing of plastic parts (UFSP4) in response to the needs of small companies that cannot afford to invest in the latest technological advances. The UFSP4 comprises two main subsystems: a mechanical support system (i.e., support structure, jig matrix and braking system) and a control system (i.e., an electronic system and an electric-hydraulic system). A relevant feature is the combination of a jig matrix and jig pins to fixate complex workpieces with different sizes. Using finite element analysis (FEA), in the mesh convergence, the total displacement converges to 0.00028781 m after 12,000 elements. The maximum equivalent stress value is 1.22 MPa for the polycarbonate plate in compliance with the safety factor. In a functionality test of the prototype performed in a production environment for one hour, the jigs fixed by the plate did not loosen, maintaining the satisfactory operation of the device. This is consistent with the displacement distribution of the creep analysis and shows the absence of the creep phenomenon. Based on FEA that underpinned the structural health computation of the braking system, the prototype was designed and built, seeking to ensure a reliable and safe device to fixate plastic parts, showing portability, low-cost maintenance and adaptability to the requirements of pad printing of automotive plastic parts.

16.
Int J Comput Assist Radiol Surg ; 17(3): 531-539, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35041132

RESUMO

PURPOSE: Effective and efficient haptic guidance is desirable for tele-operated robotic surgery because it has a potential to enhance surgeon's skills, especially in coronary interventions where surgeon loses both an eye-hand coordination and a direct sight to the organ. This paper proposes a novel haptic guidance procedure-both kinesthetic and cutaneous, which solely depends upon X-ray images, for tele-robotic system that assists an efficient navigation of the guidewire towards the target location during a coronary intervention. METHODS: Proposed methodology requires cardiologists to draw virtual fixtures (VFs) on angiograms as a preoperative procedure. During an operation, these VFs direct the guidewire to the desired coronary vessel. For this, the position and orientation of guidewire tip are calculated with respect to VFs' anatomy, using image processing on the real-time 2D fluoroscopic images. The haptic feedbacks are then rendered on to the master device depending on the interaction with attractive and repulsive, guidance and forbidden region VFs. RESULTS: A feasibility study in the laboratory environment is performed by using a webcam as an image acquisition device and a phantom-based coronary vessel model. The subsequent statistical analysis shows that, on an average, a decrease of approx. 37% in task completion time is observed with haptic feedback. Moreover, haptic guidance is found effective for most difficult branch, whereas there is a minimal significance of such haptics for the easiest branch. CONCLUSIONS: The proposed haptic guidance procedure may assist cardiologists for an efficient and effective guidewire navigation during a surgical procedure. The cutaneous haptics (vibration feedback) is found more helpful in coronary interventions compared with kinesthetic haptics (force feedback).


Assuntos
Procedimentos Cirúrgicos Robóticos , Robótica , Estudos de Viabilidade , Retroalimentação , Tecnologia Háptica , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Raios X
17.
Water Res ; 222: 118890, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35933812

RESUMO

Pb in drinking water is one of the main sources of Pb in human bodies. Besides excess lead incidents caused by lead service lines, Pb contamination in non-lead pipe systems (e.g. copper and PVC) is also on the rise. Brass fixtures and lead-solder connections are the primary sources of lead in non-lead systems, which cause intermittent peaks of Pb at the consumer tap. The concentrations of lead in tap water depend on pipeline geometry, sampling methods, and the characteristic of the pipe flow. Using a 3-dimensional computational fluid dynamics model, this study analyzes the Pb concentration variations at taps of copper water supply systems. The turbulent diffusion and shear flow dispersion are fully simulated in the model to provide the most accurate prediction. Water parcels containing lead (clouds) are formed adjacent to lead sources during stagnation and are then dispersed with the flow of water through the pipe when the tap is opened. The geometry of the pipeline has a significant impact on the monitored Pb levels. The complex flow condition in elbow areas leads to a more intense mixing of lead ions. Therefore, the Pb levels at consumer taps in complex plumbing systems in high-rise buildings are higher than in straight pipelines. When the sampling flow rate is large, the peak height of Pb is slightly higher due to higher turbulent intensity. Pb concentrations in sequential samples are predicted with sample volumes of 50, 250, 500, and 1000 mL. Lead levels may be diluted significantly when samples are taken in large volumes (e.g. 500 mL or 1 L), resulting in an underestimation of Pb levels at taps. A sample volume of 250-500 mL is recommended in sequential sampling programs on non-lead service lines in order to identify Pb sources.


Assuntos
Água Potável , Poluentes Químicos da Água , Cobre/análise , Água Potável/análise , Humanos , Chumbo/análise , Poluentes Químicos da Água/análise , Abastecimento de Água
18.
Am J Rhinol Allergy ; 36(4): 539-549, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35244478

RESUMO

BACKGROUND: Implantological procedures aimed at rehabilitating upper jaw edentulous patients (dental implant placement and/or maxillary sinus grafting) can sporadically result in sinusitis. In these patients, endoscopic sinus surgery is the most commonly employed treatment, but clinical scenarios and comprehensive management strategies are extremely heterogeneous across studies. OBJECTIVE: We sought to systematically define treatment strategies and related success rates for sinusitis following dental implantation, detailing different current treatment choices and concepts. METHODS: Adopting a PRISMA-compliant review framework, systematic searches were performed in multiple databases using criteria designed to include all studies published until November 2020 focusing on the treatment of human sinusitis following dental implantation. We selected all original studies, excluding case reports, specifying treatment modalities with objective treatment success definitions. Following duplicate removal, abstract and full-text selection, and quality assessment, we reviewed eligible articles for treatment modalities and success rates, which were pooled in a random-effects meta-analysis. RESULTS: Among 581 unique citations, eight studies (181 patients) were selected. Seven studies were retrospective case series. All studies relied on endoscopic sinus surgery, often coupled with intraoral accesses, and assessed therapeutic success endoscopically. The pooled treatment success rate was 94.7% (95% confidence interval, 91.5%-98%). Failures were treated in seven of 15 cases with further antibiotic therapies and in another seven cases with surgical revision. A single patient was lost to follow-up. CONCLUSIONS: Endoscopic sinus surgery appears to be the most frequent treatment of choice for sinusitis following dental implantation, with excellent success rates. The protean clinical picture drawn from the selected studies calls for the standardization of diagnostics and definitions in this field to enable direct comparisons between the results of different studies. The role of postoperative antibiotic therapies, which have been employed unevenly across studies, should also be prospectively investigated.


Assuntos
Implantes Dentários , Sinusite Maxilar , Sinusite , Humanos , Estudos Retrospectivos , Sinusite/cirurgia , Sinusite/complicações , Seio Maxilar/cirurgia , Endoscopia/efeitos adversos , Antibacterianos , Implantação Dentária/efeitos adversos , Sinusite Maxilar/etiologia , Implantes Dentários/efeitos adversos
19.
Front Robot AI ; 8: 730433, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34568439

RESUMO

In remote applications that mandate human supervision, shared control can prove vital by establishing a harmonious balance between the high-level cognition of a user and the low-level autonomy of a robot. Though in practice, achieving this balance is a challenging endeavor that largely depends on whether the operator effectively interprets the underlying shared control. Inspired by recent works on using immersive technologies to expose the internal shared control, we develop a virtual reality system to visually guide human-in-the-loop manipulation. Our implementation of shared control teleoperation employs end effector manipulability polytopes, which are geometrical constructs that embed joint limit and environmental constraints. These constructs capture a holistic view of the constrained manipulator's motion and can thus be visually represented as feedback for users on their operable space of movement. To assess the efficacy of our proposed approach, we consider a teleoperation task where users manipulate a screwdriver attached to a robotic arm's end effector. A pilot study with prospective operators is first conducted to discern which graphical cues and virtual reality setup are most preferable. Feedback from this study informs the final design of our virtual reality system, which is subsequently evaluated in the actual screwdriver teleoperation experiment. Our experimental findings support the utility of using polytopes for shared control teleoperation, but hint at the need for longer-term studies to garner their full benefits as virtual guides.

20.
Front Robot AI ; 8: 735566, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34621791

RESUMO

Minimally invasive robotic surgery copes with some disadvantages for the surgeon of minimally invasive surgery while preserving the advantages for the patient. Most commercially available robotic systems are telemanipulated with haptic input devices. The exploitation of the haptics channel, e.g., by means of Virtual Fixtures, would allow for an individualized enhancement of surgical performance with contextual assistance. However, it remains an open field of research as it is non-trivial to estimate the task context itself during a surgery. In contrast, surgical training allows to abstract away from a real operation and thus makes it possible to model the task accurately. The presented approach exploits this fact to parameterize Virtual Fixtures during surgical training, proposing a Shared Control Parametrization Engine that retrieves procedural context information from a Digital Twin. This approach accelerates a proficient use of the robotic system for novice surgeons by augmenting the surgeon's performance through haptic assistance. With this our aim is to reduce the required skill level and cognitive load of a surgeon performing minimally invasive robotic surgery. A pilot study is performed on the DLR MiroSurge system to evaluate the presented approach. The participants are tasked with two benchmark scenarios of surgical training. The execution of the benchmark scenarios requires basic skills as pick, place and path following. The evaluation of the pilot study shows the promising trend that novel users profit from the haptic augmentation during training of certain tasks.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa