A Novel Suction-and-Irrigation Laparoscopic Surgical Instrument: Internal Design and Preclinical Performance Evaluation

2021 ◽  
Author(s):  
Sang Wook Yi
Keyword(s):  
Three Dimensional ◽  
The Other ◽  
Suction Catheter ◽  
Surgical Instrument ◽  
Preventive Effect ◽  
Side Hole ◽  
Hand Model ◽  
Catheter Tip ◽  
Preclinical Efficacy ◽  
Printer Model

Abstract Objective: Laparoscopic instruments with suction and irrigation functions often lead to tissue damage during removal of the aspirated tissues, owing to the presence of aspiration into the side holes of their catheters. To address this problem, we designed a novel irrigation-and-suction catheter and assessed its preclinical efficacy. Methods: We made structural improvements to the irrigation-suction catheter to prevent tissue aspiration through its side holes. We ran a simulation program to perform experimental assessments before printing out the catheter tip models using a three-dimensional printer. Model 1 was the control, and Models 2, 3, and 4 were the improved models. Using these, we performed 10 repetitions of 15-s suction followed by 15-s irrigation, for a total of 5 times per model. We recorded the number of aspirations that occurred through the side holes and analyzed each model using nonparametric methods. Results: Models 2 and 3 showed fewer aspirations because the velocity and pressure around their side holes were lower than those of Model 1; this was statistically significant. On the other hand, Model 4 had a lesser preventive effect against aspiration due to higher velocity and pressure around its side holes. Conclusion: We confirmed that side-hole aspiration can be prevented with an internal structure that completely separates the irrigation and suction paths. Even if the irrigation and suction paths are not completely separated, adding a septal structure at the distal end of the catheter may prevent aspiration.

Mucociliary Transport

1978 ◽  
Vol 87 (4) ◽  
pp. 474-483 ◽  
Author(s):  
Marvin A. Sackner
Keyword(s):  
Specific Antigen ◽  
Suction Catheter ◽  
Mucociliary Transport ◽  
Side Hole ◽  
Asthmatic Patients ◽  
Nasal Mucus ◽  
Nasal Decongestants ◽  
Catheter Tip ◽  
Young Subjects ◽  
Tracheal Mucus

Our laboratory has developed bronchofiberscopic and roentgenographic techniques to measure tracheal, bronchial and nasal mucus velocities in humans and animals. We found that inhalation of specific antigen is associated with depression of tracheal mucus velocity in dogs who may or may not display bronchospasm and the mediator for this phenomenon might be SRS-A. Corroboration of the depression of tracheal mucus transport after ragweed inhalation has been obtained in susceptible asthmatic patients; prior inhalation of cromolyn blocks this reaction. Depression of tracheal mucus transport may be the earliest adverse manifestation of cigarette smoking in young subjects. Slowing of mucus transport in the bronchi occurs after suctioning with suction catheters; a newly designed suction catheter tip, the Aero-Flo®, displays less adverse effects on mucus velocity than standard end hole and side hole catheters. Nasal mucus velocity is enhanced by nasal decongestants, ingestion of hot fluids and exercise.

scholarly journals Catheter pose-dependent virtual angioscopy images visualized on augmented reality glasses

2019 ◽  
Vol 5 (1) ◽  
pp. 289-291 ◽  
Author(s):  
Felix von Haxthausen ◽  
Sonja Jäckle ◽  
Jan Strehlow ◽  
Floris Ernst ◽  
Verónica García-Vázquez
Keyword(s):  
Computed Tomography ◽  
Augmented Reality ◽  
Three Dimensional ◽  
The Other ◽  
Digital Subtraction ◽  
Additional Information ◽  
Catheter Tip ◽  
Virtual Angioscopy ◽  
The Mean ◽  
Ct Data

AbstractFluoroscopy and digital subtraction angiography provide guidance in endovascular aortic repair (EVAR) but introduce radiation exposure and require the administration of contrast agent. To overcome these disadvantages, previous studies proposed to display the pose of an electromagnetically (EM) tracked catheter tip within a three-dimensional virtual aorta on augmented reality (AR) glasses. For further guidance, we propose to create virtual angioscopy images based on the catheter tip pose within the aorta and to display them on HoloLens. The aorta was segmented from the computed tomography (CT) data using MeVisLab software. A landmarkbased registration allowed the calculation of the pose of the EM sensor in the CT coordinate system. The sensor pose was sent to MeVisLab running on a computer and a virtual angioscopy image was created at runtime based on the segmented aorta. When requested by HoloLens, the last encoded image was sent from MeVisLab to the AR glasses via Wi-Fi using a remote procedure call (gRPC), and then decoded and displayed on HoloLens. For evaluation purposes, the latency of transmitting and displaying the images was measured using two different lossy compression formats (namely JPEG and DXT1). A mean latency of 82 ms was measured for the JPEG format. On the other hand, using the DXT1 format, the mean latency was reduced by 87 %. This study proved the feasibility of creating pose-dependent virtual angioscopy images and displaying them on HoloLens. Additionally, the results showed that the DXT1 format outperformed the JPEG format regarding latency. The virtual angioscopy may add valuable additional information for guidance in radiation-sparing EVAR procedure approaches.

Three-Dimensional Reconstruction of Two Forms of the Chaperonin GRO EL

1990 ◽  
Vol 48 (1) ◽  
pp. 258-259
Author(s):  
J.L. Carrascosa ◽  
G. Abella ◽  
S. Marco ◽  
M. Muyal ◽  
J.M. Carazo
Keyword(s):  
Three Dimensional ◽  
The Other ◽  
Two Dimensional ◽  
Series Method ◽  
Three Dimensional Reconstruction ◽  
Structural Components ◽  
E Coli ◽  
Dimensional Reconstruction ◽  
Morphogenetic Factors ◽  
Tilt Series

Chaperonins are a class of proteins characterized by their role as morphogenetic factors. They trantsiently interact with the structural components of certain biological aggregates (viruses, enzymes etc), promoting their correct folding, assembly and, eventually transport. The groEL factor from E. coli is a conspicuous member of the chaperonins, as it promotes the assembly and morphogenesis of bacterial oligomers and/viral structures.We have studied groEL-like factors from two different bacteria:E. coli and B.subtilis. These factors share common morphological features , showing two different views: one is 6-fold, while the other shows 7 morphological units. There is also a correlation between the presence of a dominant 6-fold view and the fact of both bacteria been grown at low temperature (32°C), while the 7-fold is the main view at higher temperatures (42°C). As the two-dimensional projections of groEL were difficult to interprete, we studied their three-dimensional reconstruction by the random conical tilt series method from negatively stained particles.

Skin and Bone Surfaces for a Three-Dimensional Kinematic Hand Model

2009 ◽  
Author(s):  
Daewoo Park ◽  
Thomas J. Armstrong ◽  
Charles B. Woolley ◽  
Christopher J. Best
Keyword(s):  
Three Dimensional ◽  
Hand Model

An Efficient Multiple Description Coding for Multi-View Video Based on the Correlation of Spatial Polyphase Transformed Subsequences

2019 ◽  
Vol 63 (5) ◽  
pp. 50401-1-50401-7 ◽  
Author(s):  
Jing Chen ◽  
Jie Liao ◽  
Huanqiang Zeng ◽  
Canhui Cai ◽  
Kai-Kuang Ma
Keyword(s):  
Video Transmission ◽  
Video Sequence ◽  
Three Dimensional ◽  
The Other ◽  
Multiple Description Coding ◽  
Multiple Description ◽  
Prediction Mode ◽  
Gradient Based ◽  
Directional Interpolation ◽  
Description Coding

Abstract For a robust three-dimensional video transmission through error prone channels, an efficient multiple description coding for multi-view video based on the correlation of spatial polyphase transformed subsequences (CSPT_MDC_MVC) is proposed in this article. The input multi-view video sequence is first separated into four subsequences by spatial polyphase transform and then grouped into two descriptions. With the correlation of macroblocks in corresponding subsequence positions, these subsequences should not be coded in completely the same way. In each description, one subsequence is directly coded by the Joint Multi-view Video Coding (JMVC) encoder and the other subsequence is classified into four sets. According to the classification, the indirectly coding subsequence selectively employed the prediction mode and the prediction vector of the counter directly coding subsequence, which reduces the bitrate consumption and the coding complexity of multiple description coding for multi-view video. On the decoder side, the gradient-based directional interpolation is employed to improve the side reconstructed quality. The effectiveness and robustness of the proposed algorithm is verified by experiments in the JMVC coding platform.

scholarly journals On the Kirchhoff-Love Hypothesis (Revised and Vindicated)

2021 ◽  
Author(s):  
Olivier Ozenda ◽  
Epifanio G. Virga
Keyword(s):  
Free Energy ◽  
Dimension Reduction ◽  
Three Dimensional ◽  
Energy Functional ◽  
The Other ◽  
Variational Model ◽  
Two Dimensional ◽  
Elastic Plates ◽  
Kinematic Constraint ◽  
Free Energy Functional

AbstractThe Kirchhoff-Love hypothesis expresses a kinematic constraint that is assumed to be valid for the deformations of a three-dimensional body when one of its dimensions is much smaller than the other two, as is the case for plates. This hypothesis has a long history checkered with the vicissitudes of life: even its paternity has been questioned, and recent rigorous dimension-reduction tools (based on standard $\varGamma $ Γ -convergence) have proven to be incompatible with it. We find that an appropriately revised version of the Kirchhoff-Love hypothesis is a valuable means to derive a two-dimensional variational model for elastic plates from a three-dimensional nonlinear free-energy functional. The bending energies thus obtained for a number of materials also show to contain measures of stretching of the plate’s mid surface (alongside the expected measures of bending). The incompatibility with standard $\varGamma $ Γ -convergence also appears to be removed in the cases where contact with that method and ours can be made.

scholarly journals Ground Reaction Forces of Dressage Horses Performing the Piaffe

Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 436 ◽  
Author(s):  
Hilary Mary Clayton ◽  
Sarah Jane Hobbs
Keyword(s):  
Coefficient Of Variation ◽  
Three Dimensional ◽  
Individual Variability ◽  
The Other ◽  
Ground Reaction Forces ◽  
High Coefficient ◽  
Reaction Forces

The piaffe is an artificial, diagonally coordinated movement performed in the highest levels of dressage competition. The ground reaction forces (GRFs) of horses performing the piaffe do not appear to have been reported. Therefore, the objective of this study was to describe three-dimensional GRFs in ridden dressage horses performing the piaffe. In-ground force plates were used to capture fore and hindlimb GRF data from seven well-trained dressage horses. Peak vertical GRF was significantly higher in forelimbs than in the hindlimbs (7.39 ± 0.99 N/kg vs. 6.41 ± 0.64 N/kg; p < 0.001) with vertical impulse showing a trend toward higher forelimb values. Peak longitudinal forces were small with no difference in the magnitude of braking or propulsive forces between fore and hindlimbs. Peak transverse forces were similar in magnitude to longitudinal forces and were mostly directed medially in the hindlimbs. Both the intra- and inter-individual variability of longitudinal and transverse GRFs were high (coefficient of variation 25–68%). Compared with the other diagonal gaits of dressage horses, the vertical GRF somewhat shifted toward the hindlimbs. The high step-to-step variability of the horizontal GRF components is thought to reflect the challenge of balancing on one diagonal pair of limbs with no forward momentum.

scholarly journals Heritage Artefacts in the COVID-19 Era: The Aura and Authenticity of 3D Models

2021 ◽  
Vol 7 (1) ◽  
pp. 519-539
Author(s):  
Thiago Minete Cardozo ◽  
Costas Papadopoulos
Keyword(s):  
User Experience ◽  
Three Dimensional ◽  
3D Models ◽  
Essential Elements ◽  
The Other ◽  
Social Distancing ◽  
The Public ◽  
Affective Experiences ◽  
The One ◽  
Digital Engagement

Abstract Museums have been increasingly investing in their digital presence. This became more pressing during the COVID-19 pandemic since heritage institutions had, on the one hand, to temporarily close their doors to visitors while, on the other, find ways to communicate their collections to the public. Virtual tours, revamped websites, and 3D models of cultural artefacts were only a few of the means that museums devised to create alternative ways of digital engagement and counteract the physical and social distancing measures. Although 3D models and collections provide novel ways to interact, visualise, and comprehend the materiality and sensoriality of physical objects, their mediation in digital forms misses essential elements that contribute to (virtual) visitor/user experience. This article explores three-dimensional digitisations of museum artefacts, particularly problematising their aura and authenticity in comparison to their physical counterparts. Building on several studies that have problematised these two concepts, this article establishes an exploratory framework aimed at evaluating the experience of aura and authenticity in 3D digitisations. This exploration allowed us to conclude that even though some aspects of aura and authenticity are intrinsically related to the physicality and materiality of the original, 3D models can still manifest aura and authenticity, as long as a series of parameters, including multimodal contextualisation, interactivity, and affective experiences are facilitated.

scholarly journals MorphOT: transport-based interpolation between EM maps with UCSF ChimeraX

2020 ◽  
Author(s):  
Arthur Ecoffet ◽  
Frédéric Poitevin ◽  
Khanh Dao Duc
Keyword(s):  
Optimal Transport ◽  
Three Dimensional ◽  
Linear Interpolation ◽  
The Other ◽  
Supplementary Information ◽  
Conformational Heterogeneity ◽  
Supplementary Data ◽  
Image Dataset ◽  
Standard Linear ◽  
Unique Potential

Abstract Motivation Cryogenic electron microscopy (cryo-EM) offers the unique potential to capture conformational heterogeneity, by solving multiple three-dimensional classes that co-exist within a single cryo-EM image dataset. To investigate the extent and implications of such heterogeneity, we propose to use an optimal-transport-based metric to interpolate barycenters between EM maps and produce morphing trajectories. Results While standard linear interpolation mostly fails to produce realistic transitions, our method yields continuous trajectories that displace densities to morph one map into the other, instead of blending them. Availability and implementation Our method is implemented as a plug-in for ChimeraX called MorphOT, which allows the use of both CPU or GPU resources. The code is publicly available on GitHub (https://github.com/kdd-ubc/MorphOT.git), with documentation containing tutorial and datasets. Supplementary information Supplementary data are available at Bioinformatics online.

Sight distance red zones on combined horizontal and sag vertical curves

1998 ◽  
Vol 25 (4) ◽  
pp. 621-630 ◽  
Author(s):  
Yasser Hassan ◽  
Said M Easa
Keyword(s):  
Quantitative Analysis ◽  
Three Dimensional ◽  
The Other ◽  
Two Dimensional ◽  
Horizontal Curve ◽  
Sight Distance ◽  
Stopping Sight Distance ◽  
Three Dimensional Models ◽  
Highway Alignment ◽  
Current Standards

Coordination of highway horizontal and vertical alignments is based on subjective guidelines in current standards. This paper presents a quantitative analysis of coordinating horizontal and sag vertical curves that are designed using two-dimensional standards. The locations where a horizontal curve should not be positioned relative to a sag vertical curve (called red zones) are identified. In the red zone, the available sight distance (computed using three-dimensional models) is less than the required sight distance. Two types of red zones, based on stopping sight distance (SSD) and preview sight distance (PVSD), are examined. The SSD red zone corresponds to the locations where an overlap between a horizontal curve and a sag vertical curve should be avoided because the three-dimensional sight distance will be less than the required SSD. The PVSD red zone corresponds to the locations where a horizontal curve should not start because drivers will not be able to perceive it and safely react to it. The SSD red zones exist for practical highway alignment parameters, and therefore designers should check the alignments for potential SSD red zones. The range of SSD red zones was found to depend on the different alignment parameters, especially the superelevation rate. On the other hand, the results showed that the PVSD red zones exist only for large values of the required PVSD, and therefore this type of red zones is not critical. This paper should be of particular interest to the highway designers and professionals concerned with highway safety.Key words: sight distance, red zone, combined alignment.

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