The analysis of hemodynamic parameters and functional reactivity of cerebral capillaries is still controversial. The detailed mapping of tissue oxygen levels on the scale of micrometers cannot be obtained by means of an experimental approach, necessitating the use of theoretical methods in this investigating field. To assess the hemodynamics and oxygen transport in the cortical capillary network, 2D and 3D generic models are constructed (non-tree like) using random voronoi tessellation in which each edge represents a capillary segment. The modelling presented here is based on morphometric parameters extracted from physiological data of the cortex in which the spatial distribution of the diameter of the capillary is based on a Modified Murray method. This method led to a proper link between the diameter topology and flow pattern such that the maximum efficiency for flowing blood is concluded in the model of cortical capillary network. The approach is capable of creating an appropriate generic, realistic model of a cerebral capillary network relating to each part of the brain cortex because its geometrical density is able to vary the capillary density. The pertinent hemodynamic parameters are obtained by numerical simulation based on effective blood viscosity as a function of hematocrit and microvessel diameter, ESL (endothelial surface layer) effect, phase separation and plasma skimming effects. Using a solution method of the Green's function, the model is numerically developed to provide different simulations of oxygen transport for varying perfusion and metabolism in a mesoscale model of the cortical capillary network, bridging smaller and larger scale phenomena. The analysis of hemodynamic parameters (blood flow rate, velocity and hematocrit) demonstrates a consistency with the experimental observation. The distribution pattern of wall shear stress (WSS) in the network model supports the physiological data which in turn represents a proper matching between the hemodynamics and morphometrics in the cerebral capillary network. The distributions of blood flow throughout the 2D and 3D models seem to confirm the hypothesis in which all capillaries in a cortical network are recruited at rest (normal condition). The predictions showed a heterogeneous distribution in the flow pathways (aspect of length and inflow) and the pertinent transit time of red blood cell (RBC) in the network model which is dependent on varying perfusion rates. The analyses of oxygen transport in the model has demonstrated that oxygen levels in the tissue are sensitively dependent on the microvascular architecture and flow distribution. Unlike the homogeneous compartmental models, the mesoscale model presented in this study led to a prediction of tissue PO2 gradients throughout the tissue and a spatial distribution of tissue PO2 on the micron-scale for varying perfusion and metabolism. The predicted nonlinear changes in the oxygen extraction fraction (OEF) of the model as a function of the perfusion rate provide a basis for the quantitative interpretation of functional magnetic resonance imaging (fMRI) studies in terms of changes in local perfusion. The model is capable of predicting the brain oxygen metabolism under both normal and disease states, particularly, local hypoxia and local ischemia caused by misery perfusion syndrome. The hypoxic states for different perfusion rates and oxygen consumption rates demonstrated that in a significant decrease in brain perfusion (as can occur in stroke), the tissue hypoxia can be avoided by a moderate reduction in oxygen consumption rate. Increasing oxygen consumption rates (a realization of spatiotemporal stimulation of neural tissue) with respect to maintaining the tissue PO2 in the model led to a predicted flow-metabolism coupling in the model which supports the experimental studies of somatosensory and visual stimulation in humans by positron emission tomography (PET) and functional MRI (magnetic resonance imaging). A disproportionately large increase in blood supply is required for a small increase in the metabolic utilization (oxygen consumption rate) which in turn, is strongly dependent on the resting OEF such that the magnitude of the blood flow increases in the higher resting OEF.

Approved for public release, distribution is unlimited / The purpose of this study is to examine the role of the LOGCAP Logistics Support Unit (LSU) in Southwest Asia during the early stages of Operations Enduring and Iraqi Freedom. The study provides a summary of the LSU makeup, their roles, training and their processes and procedures. The study goes on to analyze the impact of the training and processes and procedures on the mission of the LSU and changes that were made during their deployment. Evidence is provided to demonstrate the difficulties the LSU encountered as a result of role confusion and inadequate training. The empirical data presented shows a correlation between role confusion and inadequate training as the cause of extended timelines and numerous changes to efforts undertaken to meet U.S. Military needs. The research then outlines the improvements that were attempted as well as the results of their implementation. In conclusion, the study provides conclusions based upon the analysis and presents three recommendations for improving the LSU to ensure the next deployment of the LSU to large-scale contingency leverages the lessons learned from this experience. Review and analysis of empirical data gathered from December 2002 through May 2003, interviews with LSU members, and General Accounting Office (GAO) audit reports provided the basis for this study / Civilian, United States Army

There is an established link between posttraumatic stress disorder (PTSD) and criminal activity. Of every 100 veterans who served during Operation Enduring Freedom (OEF)/Operation Iraqi Freedom (OIF), 11 to 20 percent are diagnosed with PTSD each year. Previous research has documented that veterans are incarcerated at higher percentages compared to nonveteran inmates, though little published research examines incidence of PTSD relative to violent crime. Using Agnew's general strain theory as the foundation, the purpose of this correlational study was to examine combat service, PTSD, and specific violent crimes as defined by the FBI as murder and nonnegligent manslaughter, forcible rape, robbery, and aggravated assaults; while controlling for branch of service, age, and sex. The sample consisted of 46 OEF/OIF inmates (federal and state) 9 of whom were convicted of a violent crime. Results from the multiple logistic regression analysis showed that combat service, PTSD, sex, and branch of service were not statistically significant predictors of imprisonment of OEF/OIF veterans for violent crime. Age, however, was statistically significant p = .029. The findings of this study contribute to social change by providing policymakers and prison administrators nuanced information (i.e., characteristic information - age, sex, branch of service, etc.) about the needs of this unique prison population with regards to reintegration. This may in turn contribute to improved reintegration initiatives to enrich the lives of veterans, their families, and the communities where veterans reside when returning from war. Focusing on reintegration will be very beneficial.

Posttraumatic Stress Disorder (PTSD), the signature wound of the Iraq and Afghanistan wars, has caused veterans to face numerous and complex challenges within their intimate relationships post-deployment. Although other studies have explored the intimate relationships of veterans, the same level of research has not focused on OEF/OIF veterans from the standpoint of dyadic adaptation using the Dyadic Adaptation Scale (DAS). The purpose of this study was to explore the level of dyadic adaptation in intimate relationships of OEF/OIF veterans who self-reported PTSD and those who did not. More specifically, this study identified the factors that were related to the level of dyadic adaptation for this population. Participants were 126 OEF/OIF veterans who were enrolled in colleges and universities throughout the state of Iowa; provided basic background information in response to a demographics questionnaire; and completed the DAS to yield scores of the participants' dyadic adaptation within their intimate relationships, the Family Crisis Oriented Personal Evaluation Scales (F-COPES) that highlighted their levels of coping, and the Family Inventory of Life Events (FILE) that measured their life stressors within the last 12 months. The results of the correlation, MANOVA, ANOVA, and hierarchical regression analyses provided four major findings and implications. First, among participants with PTSD, DAS was correlated with tours of duty, FILE, F-COPES, and pharmacologic intervention, and among participants without PTSD, DAS was correlated with FILE. Second, the total dyadic adaptation scores for participating OEF/OIF veterans suggested an overall slight level of relationship dissatisfaction. Third, participants who self-reported PTSD had lower DAS total scores than participants who did not self-report PTSD. In addition, there was a significant difference on all four subscales (cohesion, satisfaction, consensus, and affectional expression) of the DAS between the two groups of participants. Fourth, in terms of participants who self-reported PTSD, tours of duty, types of relationships, and life stressors were the only variables that positively affected dyadic adaptation. In contrast, for participants who did not self-report PTSD, FILE was the only variable that affected the dyadic adaptation. These findings have important implications that highlight areas in which clinicians, educators, and individuals within the helping professions can join the Department of Veterans Affairs' initiatives to improve the reintegration of OEF/OIF veterans into their familiar roles post-deployment. Future research should explore the relationship norms pre-deployment and across relationship statutes, the identity of military intimate partners within treatment facilities, and the perceptions of treatment and dyadic adaptation after OEF/OIF veterans receive treatment in the community by civilian providers as compared to treatment in VA facilities.

Veterans of the Iraqi and Afghanistan conflicts have frequently returned with injuries such as mild traumatic brain injury (mTBI) and posttraumatic stress disorder (PTSD). More recently, concern has been raised about the large number of returning soldiers who are diagnosed with both. Literature exists on the neuropsychological factors associated with either alone, however far less research has explored the effects when combined (PTSD+mTBI). With a sample of 206 OEF/OIF veterans, the current study employed neuropsychological and psychological measures to determine whether participants with PTSD+mTBI have poorer cognitive and psychological outcomes than participants with PTSD-o, mTBI-o, or veteran controls (VC), when groups are matched on IQ, education, and age. The PTSD+mTBI and mTBI-o groups exhibited very similar neuropsychology profiles, and both PTSD+mTBI and mTBI-o performed significantly (α=.01) worse than VC on executive functioning and processing speed measures. There were no significant differences between VC and PTSD-o on any notable neuropsychology measures. In contrast, on the psychological measures, the PTSD+mTBI and PTSD-o groups were identical to each other and more distressed than either mTBI-o or VC. These findings suggest there are lasting cognitive impairments following mTBI that are unique to the condition and cannot be attributed to known impairments associated with distress.

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This autoethnographic account details the author's ongoing struggle with combat-related posttraumatic stress disorder (PTSD) and how leisure was integral to his journey toward recovery. By showing the mental and emotional struggles of life with the disorder, this paper offers an alternative viewpoint from the traditional scientific studies of PTSD which bury soldier's voices under layers of analysis. The purpose of this paper is to deepen and expand an understanding of both combat-related PTSD and the power of leisure in an individual's recovery from combat trauma

This thesis introduces a new tower field representation, optimal tower fields (OTFs), that facilitates efficient finite field operations. The recursive direct inversion method presented for OTFs has significantly lower complexity than the known best method for inversion in optimal extension fields (OEFs), i.e., Itoh-Tsujii's inversion technique. The complexity of OTF inversion algorithm is shown to be O(m^2), significantly better than that of the Itoh-Tsujii algorithm, i.e. O(m^2(log_2 m)). This complexity is further improved to O(m^(log_2 3)) by utilizing the Karatsuba-Ofman algorithm. In addition, it is shown that OTFs are in fact a special class of OEFs and OTF elements may be converted to OEF representation via a simple permutation of the coefficients. Hence, OTF operations may be utilized to achieve the OEF arithmetic operations whenever a corresponding OTF representation exists. While the original OTF multiplication and squaring operations require slightly more additions than their OEF counterparts, due to the free conversion, both OTF operations may be achieved with the complexity of OEF operations. Furthermore, efficient finite field algorithms are introduced which significantly improve OTF multiplication and squaring operations. The OTF inversion algorithm was implemented on the ARM family of processors for a medium and a large sized field whose elements can be represented with 192 and 320 bits, respectively. In the implementation, the new OTF inversion algorithm ran at least six to eight times faster than the known best method for inversion in OEFs, i.e., Itoh-Tsujii inversion technique. According to the implementation results obtained, it is indicated that using the OTF inversion method an elliptic curve scalar point multiplication operation can be performed at least two to three times faster than the known best implementation for the selected fields.

Thesis (M.A.)--Indiana University, 2010. / Title from screen (viewed on April 1, 2010). Department of Sociology, Indiana University-Purdue University Indianapolis (IUPUI). Advisor(s): Carol Brooks Gardner, Carrie E. Foote, Lynn M. Pike. Includes vitae. Includes bibliographical references (leaves 69-74).