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Evaluation of a novel phantom‑based neurosurgical training systemMüns, Andrea, Meixensberger, Jürgen, Lindner, Dirk January 2014 (has links)
Background: The complexity of neurosurgical interventions demands innovative training solutions and standardized evaluation methods that in recent times have been the object of increased research interest. The objective is to establish an education curriculum on a phantom‑based training system incorporating theoretical and practical components for important aspects of brain tumor surgery. Methods: Training covers surgical planning of the optimal access path based on real patient data, setup of the navigation system including phantom registration and navigated craniotomy with real instruments. Nine residents from different education levels carried out three simulations on different data sets with varying tumor locations. Trainings were evaluated by a specialist using a uniform score system assessing tumor identification, registration accuracy, injured structures, planning and execution accuracy, tumor accessibility and required time. Results: Average scores improved from 16.9 to 20.4 between first and third training. Average time to craniotomy improved from 28.97 to 21.07 min, average time to suture improved from 37.83 to 27.47 min. Significant correlations were found between time to craniotomy and number of training (P < 0.05), between time to suture and number of training (P < 0.05) as well as between score and number of training (P < 0.01). Conclusion: The training system is evaluated to be a suitable training tool for residents to become familiar with the complex procedures of autonomous neurosurgical planning and conducting of craniotomies in tumor surgeries. Becoming more confident is supposed to result in less error‑prone and faster operation procedures and thus is a benefit for both physicians and patients.
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Bodies in Rhythm & Space / Bodies in Rhythm and SpaceNurk, Linda January 2023 (has links)
Who am I to wear this? I find it crucial how an item of clothing feels when worn. Instinctively tactile, visually pleasing… but when pondering further the material confronts my skin. I wonder, whose lives are sacrificed for this garment I wear? This paper presents the process of crafting my work together with nature, how I witness possibilities of self-sustained collaboration between organisms and human beings discovering each other and growing together in novel metabiosis. Growing my own craft through urban micro-farming - and rethinking the lifecycle of materials - I have found a path towards a “wild” mix of biodegradable methods in body- sculpted fashion. A method I call Couture Vivante, creating textiles together with non-human bodies and imagining possible futures of ethical production. Transforming natural elements into after-life craft, reforming ecosystems around symbiosis between source and wearer. The living materials are art pieces crafted as first prototypes in my research which places emphasis on wearable materials as progress-in-motion, rather than a static or finished product. This work connects to a wider context of socio-economic and ethical structural practice. My ideal is not a vision of utopia, it is a balanced flow between humans, vegetation, textile and living creatures. Here I see an expression of the importance of man's too often ignored dependency on nature and - perhaps - coming to a point where we can realise the inherent magic instead of harming it.
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Patienters upplevelser av fantomsmärta : En litteraturstudie / Patients’ Experience Of Phantom Pain : A literature reviewBengtsson, Michela, Aursnes, Moa January 2023 (has links)
Bakgrund: Antalet amputationer ökar successivt varje år i Sverige och därmed möter sjuksköterskor allt fler patienter som har fantomsmärtor. För att kunna möta dessa patienter behöver sjuksköterskan ha kunskap om och förståelse för fenomenet fantomsmärta. Detta för att kunna utföra en personcentrerad vård, lindra smärta och för att kunna ge en säker vård. Syfte: Syftet med litteraturstudien var att beskriva patienters upplevelser av fantomsmärta. Metod: Litteraturstudien utgår från elva artiklar med en kvalitativ ansats. Databassökningar genomfördes i Cinahl och PubMed. Litteraturstudiens valda artiklar har kvalitetsgranskats.Artiklarna analyserades systematiskt och kategoriserades i kategorier och underkategorier. Resultat: Analysen resulterade i två kategorier: fantomsmärtan ter sig på olika sätt och användning av copingstrategier. Kategorin fantomsmärtanter sig på olika sätt underbyggdes med tre underkategorier: varierande smärtförnimmelser, påverkad psykisk hälsa och påverkad social hälsa. Kategorin användning av olika copingstrategier underbyggdes med två underkategorier: behov av hanteringsstrategier och behov av information. Konklusion: Patienterna upplevde att fantomsmärtan var en individuell upplevelse som påverkade varje patient på olika plan, vilket genererade i ett varierande behov av stöd och hantering. Genom att förstå att fantomsmärta är en individuell upplevelse kan sjuksköterskan anpassa sin omvårdnad för att möta varje patients unika behov och möjliggöra en personcentrerad vård. / Background: In Sweden, the number of amputations increase annually. As a result, registered nurses are expected to meet patients with phantom pain to a larger extent. Hence, registered nurses must have knowledge and understanding about phantom pain in order to perform person-centered care and provide safe care. Aim: The purpose of the literature review was to describe patients' experiences with phantom pain. Method: The literature review is based articles on a qualitative approach. Database searches were conducted in Cinahl and PubMed. The included articles for this literature review have been quality reviewed. The articles were systematically analyzed and categorized into themes and subthemes. Results: The analysis resulted in two main categories: the phantom pain manifests itself in different ways and the use of coping strategies. The main category phantom pain manifests itself in different ways was substantiated with three subcategories: varying pain sensations, affected mental health and affected social health. The main category use of different coping strategies was supported with two subcategories: need for coping strategies and need for information.Conclusion: The patients felt that the phantom pain was an individual experience that affected each patient in a different way, which generated a varying need for support and coping strategies. By understanding that phantom pain is an individual experience, the nurse can adjust the care to meet each patient's unique needs and enable person-centered care.
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Phantom Limbs / Ghost ArchitectureHernandez Hernandez, Berenice Janice January 2022 (has links)
This project asks questions about identity, place and the role of structures as memory aids. It specifically deals with the aftermath of having moved from one culture to another, and how being surrounded by a new and foreign architectural world can interrupt one’s connec-tion to the sense of self. Working from the question “Can I recreate what I lost by using an imaginary architecture imbued with my memories?” I create what I call architectural ghosts, structures made with porcelain, wood, wire and metal as an attempt to replace the memory connections I lost when leaving Mexico.
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Developing a method for insertion of soft neural probes into peripheral nervesMelander, Klara January 2022 (has links)
The main objective of this project was to develop a method for soft neural probe insertion into a nerve. These soft probes are made of a silicon elastomer that is a few orders of magnitude less stiff than the nerve, which makes the insertion process particularly challenging. To overcome this challenge a tungsten microwire was used as an insertion shuttle to help penetrate the nerve by increasing the overall stiffness of the probe. At a first stage, the insertion process was tested on a nerve phantom (e.g. agarose gel with PDMS membrane) to control the insertion parameters and validate the insertion platform. Once the envisioned insertion method was established, the probe was implanted in a real rodent nerve. / <p>Examensarbetet är utfört vid Institutionen för teknik och naturvetenskap (ITN) vid Tekniska fakulteten, Linköpings universitet</p>
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On Radar Deception, As Motivation For Control Of Constrained SystemsHajieghrary, Hadi 01 January 2013 (has links)
This thesis studies the control algorithms used by a team of ECAVs (Electronic Combat Air Vehicle) to deceive a network of radars to detect a phantom track. Each ECAV has the electronic capability of intercepting the radar waves, and introducing an appropriate time delay before transmitting it back, and deceiving the radar into seeing a spurious target beyond its actual position. On the other hand, to avoid the errors and increase the reliability, have a complete coverage in various atmosphere conditions, and confronting the effort of the belligerent intruders to delude the sentinel and enter the area usually a network of radars are deployed to guard the region. However, a team of cooperating ECAVs could exploit this arrangement and plans their trajectories in a way all the radars in the network vouch for seeing a single and coherent spurious track of a phantom. Since each station in the network confirms the other, the phantom track is considered valid. This problem serves as a motivating example in trajectory planning for the multi-agent system in highly constrained operation conditions. The given control command to each agent should be a viable one in the agent limited capabilities, and also drives it in a cumulative action to keep the formation. In this thesis, three different approaches to devise a trajectory for each agent is studied, and the difficulties for deploying each one are addressed. In the first one, a command center has all information about the state of the agents, and in every step decides about the control each agent should apply. This method is very effective and robust, but needs a reliable communication. In the second method, each agent decides on its own control, and the members of the group just communicate and agree on the range of control they like to apply on the phantom. Although in this method much less data needs to communicate between the agents, it is very sensitive to the disturbances and miscalculations, and could be easily fell apart or come to a state with no feasible solution to continue. In the third method a differential geometric approach to the problem is studied. This method has a very strong backbone, and minimizes the communication needed to a binary one. However, less data provided to the agents about the system, more sensitive and infirm the system is when it faced with imperfectionalities. In this thesis, an object oriented program is developed in the Matlab software area to simulate all these three control strategies in a scalable fashion. Object oriented programming is a naturally suitable method to simulate a multi-agent system. It gives the flexibility to make the code more iv close to a real scenario with defining each agent as a separated and independent identity. The main objective is to understand the nature of the constrained dynamic problems, and examine various solutions in different situations. Using the flexibility of this code, we could simulate several scenarios, and incorporate various conditions on the system. Also, we could have a close look at each agent to observe its behavior in these situations. In this way we will gain a good insight of the system which could be used in designing of the agents for specific missions.
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Validation of a 1D Algorithm That Measures Pulse Wave Velocity to Estimate Compliance in Blood VesselsLeung, James 01 June 2018 (has links) (PDF)
The purpose of this research is to determine if it is possible to validate the new 1D method for measuring pulse wave velocity in the aorta in vivo and estimate compliance. Arterial pressure and blood flow characterize the traveling of blood from the heart to the arterial system and have played a significant role in the evaluation of cardiovascular diseases. Blood vessel distensibility can give some information on the evolution of cardiovascular disease. A patient’s aorta cannot be explanted to measure compliance; therefore we are using a flow phantom model to validate the 1D pulse wave velocity technique to estimate compliance.
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SAR Map of Gel Phantom in a 64MHz MRI Birdcage by Fiber-Optic Thermometry and FDTD SimulationPatel, Chirag Mukesh 01 February 2011 (has links) (PDF)
As implantable medical devices are being used more often to treat medical problems for which pharmaceuticals don’t suffice, it is important to understand their interactions with commonly used medical modalities. The interactions between medical implants and Magnetic Resonance Imaging machines have proven to be a risk for patients with implants.
Implanted medical devices with elongated metallic components can create harmful levels of local heating in a Magnetic Resonance Imaging (MRI) environment [1]. The heating of a biological medium under MRI is monitored via the Specific Absorption Rate (SAR). SAR, defined as power absorbed per unit mass (W/kg), can be calculated as , where σ is electrical conductivity of the medium in units of , |E| is the magnitude of the applied electric field in units of , and ρ is the density of the medium in units of . For continuous, uniform power deposition this can be measured experimentally as a rise in temperature over time (∆T/t), where c is the specific heat capacity of the medium in units of. To understand the SAR induced in-vivo, a phantom (Figure 2.10) is used to conduct in-vitro experiments, as it provides a controllable and repeatable experimental setup.
In order to experiment in the phantom, an understanding of the background SAR distribution and in turn the exposure field distribution of the phantom is required as per the ASTMF2182-09 standard [2]. In this work, the background SAR distribution of an ASTM standard torso phantom is measured and studied via fiber optic thermometry. The measurements are compared with an electromagnetic model simulated via FDTD, demonstrating agreement between 10-25%. A custom exposure and data collection setup (including oscilloscope, function generator, RF amplifier, directional coupler, and Neoptix Omniflex Fiber Optic Thermometry system) was integrated and automated using NI LabView.
The purpose of this thesis is to map the field distribution in a torso phantom under RF exposure from a 64 MHz MRI RF Birdcage, compare the results to an electromagnetic simulation, and finally conclude the accuracy of this method for field measurements in a standard torso phantom. Understanding the capabilities and accuracy of the fiber optic thermometry method will ultimately allow researchers to successfully apply this method to monitor background fields in their respective experimental setups (related to MRI implant heating) and understand its limitations.
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MRI susceptometry: Theory and robustness of an external phantom method for measuring bulk susceptibility from MRI field echo phase reconstruction maps applied to human liver iron overloadHolt, Randall William January 1993 (has links)
No description available.
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A LEFT VENTRICULAR MOTION PHANTOM FOR CARDIAC MAGNETIC RESONANCE IMAGINGErsoy, Mehmet 27 May 2011 (has links)
No description available.
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