El presente trabajo de investigación fue planteado tomando en cuenta que se dispone de limitada información respecto a las alteraciones ácido base en pacientes ingresados en unidades de trauma shock que son pacientes con alto riesgo de mortalidad debido a descompensación de su salud que lo lleva a inestabilidad de diversos sistemas como el cardiovascular, respiratorio, nervioso entre otros. Existe limitada información respecto a que alteraciones ácido base y en que nivel de alteración puede conllevar a mayor mortalidad en estos pacientes; es por ello que se plantea el presente trabajo teniendo como problema el siguiente. El 54.4% de pacientes fueron de sexo masculino y el restante 45.6% fueron de sexo femenino. Las edades fueron muy dispersas teniendo pacientes entre los 15 y 94 años de edad, siendo el promedio de edad de 64 años y la mayoría pacientes mayores de 50 años lo que se asocio a mortalidad con un riesgo relativo de muerte de 4.5 con respecto a los menores de 50 años. La alteración gasométrica mas frecuente fue la mixta correspondiendo a la acidosis metabólica con acidosis respiratoria en 25.6% del total de pacientes. La presencia de un ph alterado se vio en 72.5% del total de casos siendo únicamente el 27.5% gasometrías con ph normal; la acidosis de diversos tipos se presento en 75% de gasometrías alteradas (excluyendo las de ph normal) como trastorno mas frecuente frente a la alcalosis que se presento en 25% de gasometrías alteradas. la acidosis metabólica con acidosis respiratoria fue el trastorno metabólico acido base mas frecuente presentado en los pacientes fallecidos (38% de fallecidos). / --- The present investigation work was outlined taking into account that has limited information regarding the alterations acid bases on patients entered in units of trauma shock that are patient with high risk of mortality due to life threatening condition of its health that takes it to uncertainty of diverse systems like the cardiovascular, breathing, nervous among others. Limited information exists regarding that alterations acid base and in that alteration level can bear to more mortality in these patients; it is for it that thinks about the present work having as problem the following one. Conclusions: 54.4% of patients was of masculine sex and the remaining 45.6% they were of female sex. The ages were very dispersed having patients between the 15 and 94 years of age, being the average of 64 year-old age and most patient bigger than 50 years what you associates to mortality with a relative risk of death of 4.5 with regard to those smaller than 50 years. The gasometry alteration but it frequents was mixed went corresponding to the metabolic acidosis with breathing acidosis in 25.6% of the total of patient. The presence of an altered ph was seen in 72.5% of the total of cases being only 27.5% gasometrys with normal ph; the acidosis of diverse types you presents in 75% of altered gasometrys (excluding those of normal ph) like dysfunction but it frequents in front of the alcalosis that you presents in 25% of altered gasometrys. the metabolic acidosis with breathing acidosis was the dysfunction metabolic acid it bases but it frequents presented in the patients died (38% of deceaseds). bigger risk of death.

Over the past century, resuscitation of victims of hemorrhage with crystalloid or colloid solutions has proven time and again to enhance survival. Recent animal studies have shown even further improvement if drag reducing polymers (DRPs) were added in nanomolar concentrations to these resuscitation fluids. Nevertheless, our fundamental understanding of how the microcirculation responds to hemorrhage is incomplete, as well as how properties of resuscitation fluids may modulate microvascular blood flow and tissue oxygen delivery. In the present study, we examined the systemic and microcirculatory responses to hemorrhage, as they relate to hemodynamics and oxygenation, and how resuscitation fluids modify these responses. Fourteen anesthetized, male Sprague-Dawley rats were subjected to a volume hemorrhage that reduced their blood volume by 30%. After 30 minutes of hemorrhagic hypotension, the animals were resuscitated either with a conventional colloid solution of Hespan (6% hetastarch), or Hespan plus 10 parts per million of the drag reducing polymer polyethylene oxide. A volume of either fluid equal to the shed blood volume was infused over a period of one hour. All the animals were observed for two hours following the initiation of fluid resuscitation or until they expired, with measurements made at 30-minute intervals during this time. Unlike previous studies, this study found no significant improvement in blood flow and tissue oxygenation, and no significant difference between the Control and DRP groups.

Approved for public release; distribution is unlimited. / During World War II many surface combatants were damaged or severely crippled by close-proximity underwater explosions from ordnance that had actually missed their target. Since this time all new classes of combatants have been required to conduct shock trial tests on the lead ship of the class in order to test the survivability of mission essential equipment in a severe shock environment. While these tests are extremely important in determining the vulnerabilities of a surface ship, they require an extensive amount of preparation, manhours, and money. Furthermore, these tests present an obvious danger to the crew on board, the ship itself, and any marine life in the vicinity. Creating a virtual shock environment by use of a computer to model the ship structure and the surrounding fluid presents a valuable design tool and an attractive alternative to these tests. This thesis examines the accuracy of shock simulation using the shock trials conducted on USS WINSTON S. CHURCHILL (DDG 81) in 2001. Specifically, all three explosions that DDG 81 was subjected to are simulated and the resulting predictions compared with the actual shock trial data. The effects of fluid volume size, mesh density, mesh quality, and shot location are investigated. / Lieutenant, United States Navy

M.Sc. / Heat shock proteins (HSP) are a group of highly conserved proteins induced in pro- and eukaryotes by a wide variety of environmental stresses such as heat shock (HS) and oxidative injury. HSP are classified into families according to their apparent molecular mass and respective inducers. Induction of HSP is primarily regulated on transcriptional level through multiple copies of a conserved cis-acting heat shock element (HSE) in the promoter region of all hsp genes to which the heat shock transcription factor (HSF) binds. Members of the HSP family function collectively as molecular chaperone systems, and fulfil essential roles under normal conditions and provide protection and adaptation during and following stress. The induction of HSP following stress and the subsequent protection confer HSP the potential application in stress therapy and in biomarking of stress. During a previous study in which the effect of Mycobacterium tuberculosis (M.tb) on the stress response of peripheral blood moncytes (PBM) from different donors was investigated, it was observed that different individuals from different South African populations showed differential a HSP synthesis in response to M.tb. This compelled us to investigate the following: Variation in HSP synthesis in peripheral blood monocytes (PBM) from different individuals in response to the classical HSP inducer, HS. The most appropriate technique to study HSP expression on protein level. HSP synthesis was studied in PBM from 36 individuals (European (E): n=22; non-Europeans (nE): n=14) using biometabolic labelling. Three techniques were compared in the determination of HSP expression in six donors in terms of HSP synthesis, which is measured by biometabolic labelling, and accumulation of hsp70 that were measured by Western blot analysis and flow cytometry. Results obtained are : European (E) and non-European (nE) populations differed significantly (p < 0.05) from each other in spite of a prominent variation in HSP synthesis within donors ; Flow cytometry is the technique of choice for the analysis of HSP levels, since it allows fast and safe measurement of HSP levels in single cel populations within a mixed population. Data from flow cytometry correlate with Western blot analysis, but not with biometabolic labelling. The means and ranges for different HSP synthesis in different populations reported in this study, set a standard for the use of HSP as biomarker of pa environmental stress for populations inhabiting southern Africa. Efficient measurement of HSP expression as biomarker of stress can therefore be implemented in routine analysis of environmental stress, as well as investigations concerning the implications of HSP in pathology.

High-fidelity chemical kinetic models for low-temperature combustion processes require high-fidelity data from fundamental experiments conducted in idealized transient reactors, such as shock tubes and rapid compression machines (RCM). Non-intrusive laser absorption diagnostics, in particular quantum cascade lasers (QCL) in the mid-infrared wavelength region, provide a unique opportunity to obtain quantitative, time-resolved species concentration and temperature from these reactive systems. In this work, three novel laser absorption diagnostics in the mid-infrared wavelength region are presented for three different experimental applications. The first diagnostic was developed for measuring CO2 concentration using an external cavity QCL centered in the ν3 fundamental vibrational band of CO2. Absorption cross-sections were measured in a shock tube, at a fixed wavelength for the R(32) line centered at 2371.42 cm-1 (4.217 µm) over 700 – 2900 K and nominal pressures of 1, 5 and 10 bar. The diagnostic was used to measure rate coefficients for the reaction between carbon monoxide and hydroxyl radical over 700 – 1230 K and 1.2 – 9.8 bar using highly dilute mixtures. The second diagnostic was developed for measuring CO concentration using a pulsed QCL centered at 2046.28 cm-1 (4.887 µm) and an off-axis cavity implemented on the RCM. The duty cycle and pulse repetition rate of the laser were optimized for increased tuning range, high chirp rate and increased line-width to achieve effective laser-cavity coupling. A gain factor of 133 and time resolution of 10 μs were demonstrated. CO concentration-time profiles during the oxidation of highly dilute n-heptane/air mixtures were recorded and compared with chemical kinetic models. This represents the first application of a cavity-enhanced absorption diagnostic in an RCM. Finally, a calibration-free temperature diagnostic based on a pair of pulsed QCLs centered at 2196.66 cm-1 and 2046.28 cm-1 was implemented on the RCM. The down-chirp phenomenon resulted in large spectral tuning (∆v ~ 2.8 cm-1) within a single pulse of each laser at a high pulse repetition frequency (100 kHz). The diagnostic for was used to measure the temperature rise during first-stage ignition of n-pentane at nominal pressures of 10 and 15 bar for the first time.

Sepsis and its manifestation as a shock state in “septic shock” have long caused medical issues and death worldwide. The disease requires quick identification, diagnosis, and intervention with very high mortality rates prevalent otherwise. Historically this has been due to limited awareness of the disease and misclassification of its prevalence, severity, and incidence. Luckily in the past decade there has been increased interest and therefore resources devoted towards improving care and further understanding a disease that is one of the leading causes of mortality in hospitals worldwide. Over the past handful of years novel interventions and diagnostic techniques have become available. Unfortunately, in many cases these new discoveries have not yet trickled down to many of the providers on the frontline and a large amount of variation in care exists across the country. Because of the time sensitivity of sepsis, it is imperative that individuals working in the areas of healthcare who first come in contact with these patients have a clear understanding of the newest advances and resources available. In this thesis the goal is to first analyze the current protocols and standards of care for sepsis and then secondly consider new developments available both in the hospital and in prehospital emergency medical services (EMS). From the current information, strategies and protocols based on improvement of patient outcomes, can be streamlined and optimized moving forward. As predicted, there is currently an incredibly large amount of variation and knowledge on the subject with some areas implementing very progressive protocols while others still lack a sepsis protocol all together. In general, the current consensus in the field is that rapid identification and initiation of treatment is the most important component to long term survival. Improvement of outcomes therefore relies on standardization of protocols with incorporation of education components for healthcare providers. This aims to raise awareness and encourage utilization of the newest information and suggestions available. Increased interdisciplinary cooperation between prehospital providers in EMS and care providers in the hospital can also lead to improvement of recognition and treatment times for these patients. Future considerations were also examined that may potentially be applicable moving forward to improve these standards even further. There is a much opportunity available in each of these areas currently and progress is key to improving outcomes.

A dissertation submitted to the Faculty of Arts. University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the Degree of Master of Arts (Clinical Psycholoqy). Johannesburg, August 1996 / This study aims to explore the relationship between intrusion and avoidance symptoms as described in the diagnostic category in the DSM-IV (American Psychiatric Association, 1994) and frequency and level of exposure to traumatogenic events. The effects of lay counselling after the event were taken into account in the analysis, and the sample consisted of voluntary First National Bank employees, who were exposed to more than one bank robbery between December 1989 and 1992. The hypotheses of the study were that an increasing number of exposures to potentially traumatogenic events, and increasing levels of exposure to potentially traurnatoqenic events would be related to the development of avoidant and intrusion symptoms. Further, it was hypothesised that the interaction of these two variables would also be significantly related to the development of avoidant and intrusive symptoms and the nature of this interaction was explored. The scale used to measure the symptoms was the impact of Events Scale (Horowitz, 1979). Level of exposure was measured on a four point scale, which included extreme exposure with physical injury; direct threat and coafrontatlon: indirect contact with the perpetrators, and the fourth category was indirect exposure, or secondary victimisation. The results indicated that level of exposure had a significant relationship with the development of both intrusion and avoidance symptoms. Contrary to expectations, frequency of exposure was not found to be related to symptomology and it was speculated that this might have been because of the crudeness of the measure. In this regard it is of note that level of exposure as measured in this study included frequency of exposure. The results indicated further that post trauma counselling was not significantly related to symptomology. The implications of these findings were discussed in the light of the general literature in PTSD.

Thesis advisor: Donald Cox / This dissertation consists of two essays which address the origins of the business cycle. In particular, it asks: to what extent do behavioral or psychological effects, famously termed "animal spirits" by John Maynard Keynes, contribute to the amplification of business cycle fluctuations. The first essay, titled "The Labor Market Effects of Bad Economic News", examines the effects of economically pessimistic newspaper articles on hiring and employment patterns. Combining information on newspaper subscriptions with automated content analysis of newspaper articles, the paper reconstructs the flow of pessimistic news across the United States during the past recession on a county-by-county, quarter-by-quarter basis. This high resolution map of pessimistic news delivery is then used to estimate the causal impact of media pessimism on labor market outcomes. Exposure to negative news is found to suppress hiring and total employment during the early stages of the recession by up to 40% compared to pre-recession levels; overall, media pessimism can account for some 7% of jobs lost between 2007 and 2010. Further analysis of Google search data suggests that this contractionary effect is mediated by changes in public attitude caused by exposure to pessimistic stories in the media. Importantly, this study considers only articles which report negative news about the state of the national economy, rather than stories which focus on local events. It argues that the prevalence of such news stories affects local labor market conditions, but is unlikely to be affected by such conditions. This approach helps to address the simultaneity issues which have dogged previous research on the topic. The second essay, titled "Uncertainty and Risk Averse Firms in DSGE" a develops theoretical framework to rationalize the previous paper's empirical results. This paper solves a simple general equilibrium model in which firms are risk averse over future profits in a manner analogous to household risk aversion. It shows that response to increased economic uncertainty - particularly uncertainty with regards to future consumer demand, economies with risk averse firms are likely to undergo a business cycle contraction. This result also addresses a long standing problem in the RBC literature; namely, how to generate a contraction with a Keynesian demand side shock. In most models with risk averse utility-maximizing households, a reduction in aggregate demand due to consumer-side changes is expansionary. The paper argues that by introducing firm-side risk aversion into the model, this counter-intuitive behavior can be corrected in a realistic and parsimonious manner. / Thesis (PhD) — Boston College, 2014. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Economics.

A dissertation submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in ful lment of the requirements for the degree of Master of Science in Engineering. Johannesburg, April 2016 / An explosive event in an industrial gas transmission pipe stresses the pipe and can result in pipe rupture and separation at weak points. A shock wave results propagating from the high pressure section of the pipe, through the gap and to the low pressure section. The present study simulates numerically and experimentally the resulting ow eld at the position of pipe separation and propagation conditions in both pipe sections. The e ects of gap width, gap geometry and shock Mach number variation are investigated. Shock Mach numbers of 1.34, 1.45,1.60 and 2.2, gap widths of 40mm to 310mm were used. All variations of boundary conditions were found to have an e ect on the propagation conditions as well as the development of the ow features within the gap. The variation of the gap geometry was done for a pipe gap and a anged gap experimentally. Extended geometries were simulated numerically. For the pipe gap, the incident shock wave accelerated the gas in the upstream pipe to high subsonic speeds and continued in the downstream pipe at a much reduced strength. A strong expansion propagated into the ow in the upstream pipe causing a signi cant pressure drop from the initial post-shock pressure. Expansion waves at the out ow resulted in supersonic speeds as the ow entered the gap for Mach 1.45 and 1.6. A notable feature was the formation of a standing shock at the inlet to the downstream pipe. In addition to the standing shock, shock cells of alternating shocks and expansions developed within the gap essentially controlling the propagation conditions in the downstream pipe. For the lower Mach number of 1.3, no sharp discontinuities were noticed. The e ect of the gap width was found on the nature of the shock cells within the gap. The propagation conditions in the downstream pipe showed that the pressure is initially unsteady but becomes more uniform, controlled by the developed wave system in the gap. For the anged gap case, the ow within the gap is con ned for much longer and hence produced much more intense and complex ow feature interactions and an earlier transition of the ow to turbulence. Numerical investigations for a burst pipe gap, for a gap with a di erent diameter downstream pipe and a gap with a 90-degree bend downstream pipe produced peculiar ow features. / MT2016

Student Number: 0008522F Master of Science Faculty of Engineering & The Built Environment School of Mechanical, Industrial & Aeronautical Engineering / An aircraft travelling at supersonic speeds close to the ground generates a bow wave, which is reflected off the ground surface. When the aircraft enters a valley, the three-dimensional bow wave is reflected off the valley walls, such that it could focus behind the aircraft. Complex threedimensional wave surfaces will result. The real situation of an aircraft entering a valley can be modelled and tested experimentally in a shock tube. To simulate the process a planar shock wave, generated in a shock tube, is moved over several notched wedge configurations. Schlieren photographs were produced to identify the resulting complex three-dimensional wave structures and then verified by three-dimensional CFD. The valley geometries investigated are rectangular, triangular, parabolic and conical. Three hill geometries were also investigated. The three-dimensional reflected surfaces from the rectangular valleys were found to vary only slightly as the valley floor inclination is increased. As the incident wave interacts with both the wedge and valley floor surfaces two prominent reflections occur. A primary reflected wave surface is generated from regular reflection off the wedge. This surface flows over into the valley contacting the incident wave at a second contact point. A secondary reflected wave is found underneath the primary reflected wave, generated due to Mach reflection occurring over the full width off the valley floor. The area of the incident wave between the second contact point and the triple point is seen to bow out into the downstream flow. The Mach stem of the reflection off the valley floor tends to become less pronounced for the larger valley floor inclination angles. In all the rectangular valleys, a shear layer is present, cascading down the valley wall and then along the valley entrance. The shear layer tends to decrease in size as the valley floor inclination increases. Both prominent reflected shock surfaces are almost conical in nature at close proximity to the valley wall. The triangular valleys show similar reflection patterns as the rectangular valleys. As the incident shock wave initially interacts with the wedge surface only regular reflection occurs. The resulting reflected wave forms the primary reflected surface which flows over into the valley. The reflection changes to Mach reflection as the incident wave interacts with the valley floor. The Mach stem of the reflection off the valley floor increases in characteristic height as one moves from the valley entrance wall to the plane of symmetry. The Mach stem is much smaller for the higher valley floor inclinations. A secondary reflected wave is found underneath the primary reflected surface. The secondary wave is Mach reflection near the plane of symmetry which turns iii to regular reflection closer to the valley wall. The primary and secondary reflected surfaces merge near the plane of symmetry and again along the wedge surface. A shear layer is found to cascade down the valley entrance wall for all geometries, decreasing in strength as the valley inclination angle increases. The parabolic valleys show similar reflection patterns as the triangular valleys. As the incident wave interacts with both the wedge and valley surfaces two reflections occur. The reflection off the wedge surface is regular. As the incident wave flows over into the valley the initial reflection off the valley floor is regular. This regular reflection then turns into Mach reflection the closer one moves to the symmetry plane. The Mach reflection off the valley floor forms a secondary reflected wave underneath the primary reflected wave that is found to flow over into the valley. The primary reflected wave contacts the incident wave at a second contract point found above the triple point. This contact point moves closer to the triple point and eventually along the secondary reflected wave as the incident wave advances downstream. The second contact point at a single time instant is also seen to move closer to the triple point as one moves closer to the plane of symmetry. A shear layer is found cascading down the valley entrance wall. The secondary reflected wave of the Mach reflection off valley floor forms a semi-circular surface which contacts the floor just after the shear layer. The Mach reflection off the valley floor changes to regular reflection as the surface begins to climb up along the valley entrance wall. The conical valleys once again show similar reflection patterns as those found in the other valley geometries. As the incident wave interacts with both the wedge and valley surfaces two reflections occur. Regular reflection occurs off the wedge surface with the resulting primary reflected wave flowing over into the valley. This primary reflected wave contacts the incident shock at a second contact point in the valley. The reflection off the valley floor is regular close to the valley entrance wall changing to Mach reflection nearer the symmetry plane. The reflected wave from the Mach reflection forms the secondary reflected surface found beneath the primary reflected wave. The secondary reflected Mach wave changes to regular reflection as the surface nears the valley wall, with the reflection point travelling along the valley floor until coincident with the valley entrance wall, where it then travels along the entrance wall. The second contact point found on the incident wave is found above the triple point and moves down the incident shock to eventually coincide with the triple point. A weak shear layer is found to cascade down the valley entrance wall. A weak separation also occurs at the entry point of the valley. iv The three hill geometries, triangular, parabolic and conical, all display similar reflection patterns. As the incident wave advances downstream regular reflection occurs off both the wedge and hill surfaces. The reflected waves come together at a point off the surface. At this point a double triple point occurs with two resulting Mach stems. One Mach stem contacts the wedge surface while the other contacts the hill surface. The resulting double Mach stem surface wraps around the base of the hill getting progressively tighter the closer it gets to the incident wave. The only major differences between all three geometries is the shape of the resulting reflected wave off the hill surface (which tends to follow the same geometric shape as the hill) and the distance between the two triple points for the conical and parabolic hills tends to be larger than that found for the triangular hill.