Objective- To investigate the extent to which changes in body fat percentage (BF%) and weight (BW) relate to changes in C-reactive protein (CRP) in women, while statistically controlling for possible confounders, such as age, initial body weight, and menopause status. Methods and Results- A cohort of 150 free-living subjects was followed prospectively over a 2½-year period. BF% was measured using dual energy X-ray absorptiometry (DEXA), while BW was determined with a calibrated, electronic scale. There was no significant relationship between changes in BF% and CRP, regardless of age, initial BW, and menopause status. However, changes in BW were predictive of changes in CRP (F=7.75, p=0.006, R2=0.05). The association remained significant after adjusting for differences in baseline age, initial BW, and menopause status (F=9.17, p=0.003, R2=0.08). Conclusions- Changes in BF% are not predictive of changes in CRP. However, in agreement with other studies, variations in BW are predictive of changes in CRP. Evidently, changes in CRP are more a function of changes in BW than changes in BF% in middle-aged women. If a causal relationship is assumed, then weight gain over time is likely to increase risk of elevated CRP levels and possibly cardiovascular disease.

There exists a great need for armor systems with greater mass efficiencies and ballistic limits. This thesis explores the development of a new field of armor capable of satisfying the increased demand for modern armor: Mechanically Reactive Armor or MRA. More specifically, the thesis focuses on Compliant MRA or CMRA. From the physics governing projectile-armor interactions, principles governing successful design of MRA are identified and presented. These principles or design approaches focus primarily on rejecting, minimizing, or absorbing the incoming projectile's kinetic energy. After identifying these principles, the specific mechanical functions required by the principles are isolated. These functions represent the physical behavior and capabilities of real mechanisms that satisfy the specific design principles. Using these mechanical functions and other benchmark concepts as a guide, established concept generation methodology is used to identify families of CMRA concepts that could supply the identified mechanical functions. These concept families are then narrowed by comparison of their respective ability to supply the required mechanical functions. The remaining concepts are selected for further study and simulation. In order to provide more detailed insight into the behavior of specific designs of these concepts, a quantitative model is developed. This simplified model is capable of predicting the behavior of the CMRA system when impacted by a ballistic projectile. After development, the model is then implemented to search the design space of the narrowed concepts. The search of the design space reveals important trends to be used in the design of CMRA elements. Finally, the feasibility of the specific designs is evaluated to judge their practicality in terms of practical materials and dimensions. It is shown that the concepts hold significant promise but require further design and development to provide the most desirable performance.

With the rapid increase in miniaturization of mechanical components, the need for a hard, protective coatings is of great importance. In this study we investigate some of the mechanical, chemical and physical properties of the SiCN thin films. Thin films of amorphous silicon carbide nitride (a-SiCxNy) were deposited in a RF magnetron sputtering system using a powder pressed SiC target. Films with various compositions were deposited on to silicon substrate by changing the N2/Ar gas ratios during sputtering. Nano-indentation studies were performed to investigate the mechanical properties such as hardness and reduced modulus of the SiCN films. Surface morphology of the films was characterized by using atomic force microscopy (AFM). X-ray photoelectron spectroscopy (XPS) data indicated that the chemical status is highly sensitive to the nitrogen ratios during sputtering. Further, the films were annealed in dry oxygen ambient in the temperature range of 400 – 900°C and characterized using XPS to investigate the chemical composition and oxidation kinetics at each annealing temperature. The surface roughness of these films was studied as a function of annealing temperature and film composition with the help of a "Veeco" optical profilometer. Nano-indentation studies indicated that the hardness and the reduced modulus of the film are sensitive to the N2/Ar ratio of gas flow during sputtering. AFM studies revealed that the films become smoother as the N2/Ar ratio is increased. XPS data indicated the existence of C-N phases in the as-deposited films. The study of oxidation kinetics of RF sputter deposited SiCN thin films, using XPS, suggest that N2 co-sputtering helps to suppress the formation of a surface oxide, by allowing un-bonded Si to bond with N and C inside the vacuum chamber as opposed to bonding with O in atmosphere.

Two thirds of American adults are overweight and almost half of those qualify as obese. Obesity independently increases risk for cardiovascular disease (CVD), type II diabetes (T2D), and hypertension; thus, strategies to reduce risk in this population are desperately needed. Oxidative stress and inflammation are two perpetuators of these chronic diseases that are often elevated in obesity. Interventions that target reductions in oxidative stress and inflammation may help to reduce co-morbidities associated with obesity. Weight loss is shown to reduce oxidative stress and inflammation. However, the composition of and food choices within the weight loss diet may influence the response of these factors to weight loss, and has not been adequately assessed. We first tested whether there were differential effects of a conventional low-fat, high carbohydrate weight loss diet (LF) and the Atkins diet (a popular low carbohydrate, high fat diet (HF)) on oxidative stress and inflammation. We demonstrated that HF raised C-reactive protein (CRP) levels relative to LF in overweight and obese women over four weeks. This finding raises questions as to the long term safety of the HF eating plan in terms of CVD risk. We next examined the role of oxidative stress in the HF diet-induced increase in inflammation by evaluating the effects of an antioxidant supplement versus a placebo in conjunction with HF in overweight and obese men and women. Although our full hypothesis was not supported, as oxidative stress did not increase with HF, the trend for a differential effect on CRP when antioxidants were consumed is provocative. It suggests that future research on the connection between oxidative stress, the macronutrient content of the diet, and inflammation in obesity is warranted. Regarding the effects of specific fats, epidemiological research shows that diets high in saturated fat (SFA) are associated with higher CVD risk while diets higher in omega 3 fats (n-3FA) with lower CVD risk. However, the acute effects of these fats on indices of inflammation and oxidative stress are less understood, particularly in the overweight/obese population. As the majority of the time is spent in the postprandial state, the acute responses to high fat meals are gaining attention for their contribution to endothelial dysfunction and CVD. We showed that acute meals high in SFA increased a marker of endothelial activation (ICAM-1) which could contribute to the atherogenic associations with SFA. Conversely, including n-3FA in a high fat meal acutely enhanced NF-κB activation in circulating mononuclear cells; however, there were no increases in any inflammatory proteins measured over the 6 h postprandial period. It is apparent that dietary macronutrients can influence factors associated with chronic disease in overweight and obese individuals. The evidence presented here may help to refine dietary recommendations for this population. / Ph. D.

Every year millions of individuals suffer from traumatic brain injury (TBI) leading to permanent disabilities and even death. Mild TBI (mTBI) is the most common form of TBI comprising about 80-90% of all occurrences. Following a CNS insult like an mTBI, astrocytes can undergo activation resulting in the transformation into reactive astrocytes (RAs). RAs also play an important role in brain remodeling following an mTBI. Research on the mechanical complexity of the brain has important implications for understanding brain function and dysfunction, as well as for the development of new diagnostic and therapeutic tools for neurological disorders. This study aimed to develop and utilize an emph{in vitro} mTBI platform to investigate the intricate mechanical interplay between the extracellular matrix (ECM) and astrocytes following a simulated mTBI. Cellular mechanisms underlying mTBI and the contribution of mechanical forces that result in prolonged brain damage are yet to be comprehensively understood. Successfully devised mechanical characterization techniques for tissue-engineered models were developed utilizing atomic force microscopy and rheology. Astrocyte exposure to high-rate overpressure revealed altered mechanical properties of the surrounding matrix and decreased expression of laminin and collagen IV, which are critical for brain function and may contribute to pathologies associated with mTBI. The developed platform and methods provide new insights into the mechanistic complexity underlying ECM-astrocyte interactions following an mTBI. / Master of Science / Every year, millions of people suffer from traumatic brain injury (TBI), which can lead to permanent disabilities or even death. The most common form of TBI is mild TBI (mTBI), which accounts for 80-90% of all cases. After a mTBI, astrocytes, the most common cell type in the brain, can become activated and turn into reactive astrocytes (RAs). RAs play an important role in the brain's recovery following a mTBI. Understanding the mechanical complexity of the brain is crucial for developing new diagnostic and therapeutic tools for neurological disorders. This study aimed to investigate the mechanical interplay between the modeled tissue and astrocytes following a simulated mTBI using an emph{in vitro} platform. Development of mechanical characterization techniques allowed for any alterations caused by the astrocytes to their environment to be detectable. The astrocyte exposure to the simulated mTBI revealed altered mechanical properties of the surrounding environment and decreased expression of proteins laminin and collagen IV, which are critical to brain function and may contribute to pathologies associated with mTBI. This study provides new insights into the mechanistic complexity underlying the interaction between astrocytes and their environment, which could lead to the development of new treatments.

Yes / Reactive Powder Concrete (RPC) is a new type of cementitious materials with a complex hydration mechanism, and active admixtures greatly influence the hydration reaction, formation of hydration products, and evolution of microstructure. In order to comprehensively study the quantitative effects of active admixtures contents, namely silica fume, slag and fly ash, on hydration characteristics, hydration products, and microstructure of RPCs, tests of workability, setting time, electrical conductivity, bound water and mechanical properties were conducted. Furthermore, a series of properties including morphology and micro-structure characteristics of RPCs were analyzed by thermogravimetric (TG) analysis, X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), mercury intrusion porosimetry (MIP), Brunauer-Emmet-Teller (BET), and scanning electron microscope (SEM). The results indicate that the initial hydration reaction rate of RPCs is reduced by partly replacing cement with active admixtures. The pozzolanic effect created by the active admixtures enhances hydration and improves RPC's compressive and flexural strength. RPCs made of cement-silica fume mixture exhibit the best macroscopic properties. The adoption of silica fume promotes the production of C-S-H gel during hydration and exerts pozzolanic and crystal nucleation effects to promote cement hydration. RPCs made of pure cement exhibit 15.3% porosity after 28 days of hydration, with the largest proportion of less harmful pores in the microstructure. The porosity is reduced to 5.2% when cement is partially replaced with silica fume, and the microstructure is dominated by harmless pores. When replacement of silica fume is kept at 25%, using slag powder or fly ash substitute part of cement also reduces the number of less harmful pores. It is beneficial to add slag powder to increase the number of gel pores, whereas fly ash reduces the number of gel pores. The investigation presented in this paper would contribute to the production of low cost and environmentally-friendly RPCs, and accelerate the wider applications of ultra-high performance concrete (UHPC) in engineering structures.

Software developers spend more time on reading than writingcode. Comprehensible code therefore has the potential tosignificantly improve software development andmaintenance by lowering the time needed for understandingexisting code. Previous research suggest that the choice ofProgramming paradigm may affect code comprehension. Thepresent study evaluates if a positive effect of ReactiveProgramming on comprehension can be attested incomparison to Procedural Programming. We let human testsubjects solve bugs in code-snippets of commonfunctionalities implemented either according to ReactiveProgramming or Procedural Programming in the Javalanguage and RxJava, its ReactiveX implementation. Thecomprehensibility of the code is measured by the test subjects’time consumption, with lower values indicating highercomprehensibility and higher values lowercomprehensibility.Within this study we also study the effect of prior knowledgeof reactive programming, and background in programming,on the results, by having test subjects from two groups: (1)software students with experience in Reactive Programming,and (2) experienced software developers and engineers withless experience in Reactive Programming.All tests took part in a tool of our design, the CodeComparator.Our results show that reactive puzzles are solved faster,suggesting higher comprehensibility, although highdispersion in solvability time, especially for the proceduralsolutions, make it difficult to assess the validity of this timedifference. The positive effect is notable in the student groupwhereas we cannot conclude if the other group solves reactiveor procedural puzzles faster

京都大学 / 新制・課程博士 / 博士(理学) / 甲第24179号 / 理博第4870号 / 新制||理||1697(附属図書館) / 京都大学大学院理学研究科化学専攻 / (主査)准教授 水畑 吉行, 教授 若宮 淳志, 教授 倉田 博基 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

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