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You searched for subject:(bTBI). Showing records 1 – 3 of 3 total matches.

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Texas A&M University

1. Anumolu, Pratima. Computational Modeling and Optimization of a Novel Shock Tube to Study Blast Induced Traumatic Brain Injury.

Degree: 2014, Texas A&M University

Over the last decade, soldiers fighting in Iraq and Afghanistan are being exposed to blasts from powerful explosives with improvised detonation techniques. These blasts put them at high risk of closed head non-impact Blast-induced Traumatic Blast Injury (bTBI). bTBI is caused by interaction of shock-wave. It is a debilitating condition, but goes undiagnosed for several months. The pathology of bTBI is poorly understood making diagnosis, treatment, and prevention of bTBI difficult. One way to study it is to construct a shock tube that replicate blast profile. However, this method does not replicate blast conditions perfectly. The goal of this research is to improve shock tube as a research tool, for studying bTBI, by better replicating military ordnance. Various 2D models to simulate the shock wave propagation in a shock tube to see the effects of varying shock tube geometry and working fluid on the blast profiles were developed. Ranges of different parameters evaluated are: tube length - 5ft to 25ft; tube diameter - 8? to 16?; working fluid - compressed air and helium; burst pressure- 20 to 55 psi. A total of 240 simulations were run to evaluate the effect of these factors on the pressure profile. Computations were carried out using commercial software, Star CCM+ (CD-adapco, NY, USA). Assumptions used to model the flow were unsteady, inviscid, compressible, axisymmetric flow with time-step of 1e-5s. Multiple regression was run on these parameters to establish empirical relationship with pressure profile. CFD model was validated using experimental data from Robbins-Moreno shock tube. Results show that as the burst pressure increases, peak overpressure, positive phase duration, and impulse also increase. Increasing tube diameter decreases peak. Change in tube length does not have a significant effect on peak overpressure, positive phase duration, and impulse. Working fluid was most significant factor determining the magnitude of impulse and duration. In conclusion, the empirical formulas developed using CFD model of the shock tube provide reasonable predictions about the key features of a pressure profile that and their dependence on the shock tube geometry, working fluid, and burst pressure. This knowledge will be used to improve shock tube to study bTBI. Advisors/Committee Members: Moreno, Michael (advisor), Criscione, John (committee member), van Loon, Raoul (committee member), Ranjan, Devesh (committee member).

Subjects/Keywords: bTBI; CFD

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Anumolu, P. (2014). Computational Modeling and Optimization of a Novel Shock Tube to Study Blast Induced Traumatic Brain Injury. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/153530

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Anumolu, Pratima. “Computational Modeling and Optimization of a Novel Shock Tube to Study Blast Induced Traumatic Brain Injury.” 2014. Thesis, Texas A&M University. Accessed September 22, 2019. http://hdl.handle.net/1969.1/153530.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Anumolu, Pratima. “Computational Modeling and Optimization of a Novel Shock Tube to Study Blast Induced Traumatic Brain Injury.” 2014. Web. 22 Sep 2019.

Vancouver:

Anumolu P. Computational Modeling and Optimization of a Novel Shock Tube to Study Blast Induced Traumatic Brain Injury. [Internet] [Thesis]. Texas A&M University; 2014. [cited 2019 Sep 22]. Available from: http://hdl.handle.net/1969.1/153530.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Anumolu P. Computational Modeling and Optimization of a Novel Shock Tube to Study Blast Induced Traumatic Brain Injury. [Thesis]. Texas A&M University; 2014. Available from: http://hdl.handle.net/1969.1/153530

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


University of Illinois – Chicago

2. Kanagaraj, Johnwesly A. Cellular Reparative Effects of Poloxamer P188 in Blunt Force Trauma to Brain Tissue.

Degree: 2016, University of Illinois – Chicago

Blast–induced traumatic brain injury (bTBI) is a neurological dysfunction that can result from a sudden exposure to blunt force and leading to adverse health consequences. Currently, there are no treatment or preventive measures that specifically target TBI. Several hypotheses have been formulated to explain such injury, including the generation of microcavitation (e.g., microbubbles) in the brain that subsequently collapses with high pressure causing both physically and biochemically adverse effects. This study was designed to explore and elucidate potential therapeutic effects of surfactants (poloxamers P188) to partially repair the damaged brain tissue due to bTBI. A controlled electrical discharge system was designed and validated to generate microbubbles of 20 to 30 µm in size. Using this system, we tested the hypothesis that triblock surfactants poloxamers can partially rescue astrocytes exposed to collapse of microbubbles. Immediate impact of collapse of microbubbles was to create a crater-like region in which the cells detached from the substrate. Of the cells that survived the initial mechanical insult at the periphery of the crater, we monitored the calcium dynamics and production of reactive oxygen species (ROS) using fluorescence microscopy. Based on our results, we report the poloxamers are capable of rescuing partially damaged astrocytes and restore the cellular functionality. P188 has been shown to seal the damaged cell membrane and facilitate to recover the membrane integrity. Since P188 is FDA-approved, the polymeric compounds may offer a potential therapeutic treatment for those exposed to blunt force trauma. Advisors/Committee Members: Cho, Michael (advisor).

Subjects/Keywords: bTBI; poloxamers; microbubbles; astrocytes; calcium dynamics; reactive oxygen species; fluorescent microscopy

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Kanagaraj, J. A. (2016). Cellular Reparative Effects of Poloxamer P188 in Blunt Force Trauma to Brain Tissue. (Thesis). University of Illinois – Chicago. Retrieved from http://hdl.handle.net/10027/20913

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Kanagaraj, Johnwesly A. “Cellular Reparative Effects of Poloxamer P188 in Blunt Force Trauma to Brain Tissue.” 2016. Thesis, University of Illinois – Chicago. Accessed September 22, 2019. http://hdl.handle.net/10027/20913.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Kanagaraj, Johnwesly A. “Cellular Reparative Effects of Poloxamer P188 in Blunt Force Trauma to Brain Tissue.” 2016. Web. 22 Sep 2019.

Vancouver:

Kanagaraj JA. Cellular Reparative Effects of Poloxamer P188 in Blunt Force Trauma to Brain Tissue. [Internet] [Thesis]. University of Illinois – Chicago; 2016. [cited 2019 Sep 22]. Available from: http://hdl.handle.net/10027/20913.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Kanagaraj JA. Cellular Reparative Effects of Poloxamer P188 in Blunt Force Trauma to Brain Tissue. [Thesis]. University of Illinois – Chicago; 2016. Available from: http://hdl.handle.net/10027/20913

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


University of Alabama

3. Jenson, Daniel Bryan. A multiscale analysis of blast impact mitigation on the human head.

Degree: 2014, University of Alabama

The effectiveness of helmets in preventing shrapnel wounds and internal damage due to blast shock waves has been studied. Carbon nanotubes and similar nanostructures have also recently generated heightened interest due to their strength-to-weight ratio and other unique properties. Therefore, to understand and develop a helmet with improved protection, it is necessary to develop computational procedures that will enable the accurate modeling of traumatic head injuries as well as the precise measurement of the mechanical properties of nanostructures and how these characteristics behave when embedded as an advanced composite structure into a helmet. In this study, a multiscale simulation strategy is used to estimate the mechanical characteristics of advanced composite structures with embedded nanostructures. In most of the previous theoretical works, an analysis dedicated to improving the design of the helmet using composite structures was not included due to a lack of understanding of the interactions of the nanostructures with the matrix materials. In this work, the role of the helmet on the over pressurization and impulse experienced by the head during blast shock wave and blunt force trauma due to shrapnel impacts is studied. In addition, the properties of nano-composite structures are estimated using molecular dynamics (MD) simulations and then scaled to the macroscopic level using continuum mechanic formulations. This modeling is further developed using Finite Element (FE) analysis to demonstrate the effectiveness of various types of nanostructures in energy absorption. An analysis is carried out on a model of an unprotected head to compare the results to those obtained when protected by a helmet containing different nanostructures. The developed multiscale model is used to improve the composition of helmets and the general understanding of the effects of blast shock wave and shrapnel impacts thereby leading to the mitigation and prevention of traumatic head injuries. (Published By University of Alabama Libraries) Advisors/Committee Members: Unnikrishnan, Vinu, Roy, Samit, Mahmoodi, Nima, University of Alabama. Dept. of Aerospace Engineering and Mechanics.

Subjects/Keywords: Electronic Thesis or Dissertation;  – thesis; Aerospace engineering; Biomechanics; Mechanics; Brain; bTBI; Conwep; Friedlander; Helmet; Pressure

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Jenson, D. B. (2014). A multiscale analysis of blast impact mitigation on the human head. (Thesis). University of Alabama. Retrieved from http://purl.lib.ua.edu/128101

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Jenson, Daniel Bryan. “A multiscale analysis of blast impact mitigation on the human head.” 2014. Thesis, University of Alabama. Accessed September 22, 2019. http://purl.lib.ua.edu/128101.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Jenson, Daniel Bryan. “A multiscale analysis of blast impact mitigation on the human head.” 2014. Web. 22 Sep 2019.

Vancouver:

Jenson DB. A multiscale analysis of blast impact mitigation on the human head. [Internet] [Thesis]. University of Alabama; 2014. [cited 2019 Sep 22]. Available from: http://purl.lib.ua.edu/128101.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Jenson DB. A multiscale analysis of blast impact mitigation on the human head. [Thesis]. University of Alabama; 2014. Available from: http://purl.lib.ua.edu/128101

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

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