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Accurate analysis of the hepatic vasculature is of great importance for many medical applications, such as liver surgical planning and diagnosis of tumors and/or vascular diseases. Vessel segmentation is a pivotal step for the morphological and topological analysis of the vascular systems. Physical imaging limitations together with the inherent geometrical complexity of the vessels make the problem challenging. In this work, we present an automatic method to separate and render the portal and hepatic veins in multi-phase CT images. This methods involve image enhancement using an Hessian filter, automatic selection of thresholds to separate vasculature and liver parenchyma, and an iterative classification step for vessel separation. We also propose a series of methods and techniques that segment the portal vein and the hepatic vein, and...
An efficient response surface construction method for fatigue life prediction is investigated in this study, based on the Gaussian process (GP) modeling approach. The model is applied to fatigue crack growth analysis, in order to save the computational effort in calculating the stress intensity factor through finite element analysis. The advantage of GP modeling is shown through comparison with traditional methods such as polynomial approximation developed by previous researchers. Then the GP method is applied to railroad wheel crack growth analysis. The GP method is also applied to develop an analytical model of fatigue crack growth data. An adaptive sample selection procedure is implemented to improve the accuracy of the GP model. The use of the GP approach can significantly reduce the number of tests required to model the fatigue cr...
As systems age and require new efforts for revitalization, the original supply chain faces risks that once were not an issue. The supply chain for a legacy system can diminish over time as factors such as new technologies, economic shifts and global considerations redirect suppliers. This study examines the potential level misalignment between engineers, who develop legacy system supply chain strategies, and managers who oversee the function of these systems. A two part survey, assessing the risk of a legacy supply chain, compares the responses of 331 engineers with 203 upper managers, all of who are associated with systems engineering. Despite the potential for functional misalignment among engineers and managers, we found few statistically significant differences of perceptions of supply chain risks. There were, however, notable diff...
Human replication protein A (RPA) is a single-stranded DNA (ssDNA) binding protein involved in DNA metabolism. RPA binds ssDNA transiently during initiation of DNA replication. When this dissertation research began, the mechanisms of RPA loading and displacement were not known. Two SV40 T antigen-binding sites on RPA, DNA binding domains A and B of RPA70 (RPA70AB) and C-terminus of RPA32 (RPA32C) have been defined. The origin DNA-binding domain (OBD) of T antigen binds to both sites. Physical interaction between T antigen OBD and RPA70AB was required for the loading of RPA onto ssDNA during initiation of SV40 DNA replication. T antigen formed a ternary complex with RPA and 8-mer ssDNA, but was released from RPA-ssDNA complex when longer ssDNA was available. Thus the ternary complex is a key intermediate for RPA loading. Although RPA32C...
The current study examined posttraumatic stress (PTSS), depression, and anxiety symptoms in a sample of mothers and fathers of children with cancer. Mothers (n = 153) and fathers (n = 76) of 154 children with cancer completed self-report measures of psychological distress between 12 and 108 days after their childs initial diagnosis or most recent date of relapse. Descriptive statistics and distributions of psychological symptoms were examined in detail. Significant relations among symptoms, demographic variables, and medical variables were relatively few in number and small in magnitude. Comparisons demonstrated that lower socioeconomic status and being a single parent may be risk factors for elevated psychological distress. The current findings suggest that a large percentage of mothers and fathers experience clinically-significant e...
The presence of severe search frictions undermines technological development since the long waiting period for the subsequent trade would discourage the selectiveness of product qualities. The introduction of money will alleviate search frictions, and hence improve the technology choice.
A new asset pricing formula is proposed for an economy with heterogeneous prior beliefs. It helps explain why stock prices may deviate from the expected fundamental values, and how speculators can make profits from stock price manipulations provided the presence of informational frictions. An empirical wavelet analysis of stock market comovements reveals some features of the informational spillovers from NASDAQ and S&P500 to some Eastern Asian markets.
Non-enzymatic modification by glucose of proteins induces protein damage through the formation of advanced glycation end products (AGEs). AGEs have been implicated in the pathogenesis of a number of diseases including diabetes. Pyridoxamine (PM) is an in vitro inhibitor of the formation of AGEs, which acts by blocking the conversion of the Amadori intermediate to AGEs. In both animal experiments and human clinical trials, PM has shown promising results in delaying the onset of diabetic renal disease. The goal of this study was to use model proteins to gain insight into how glucose modifications alter protein functionality and how PM prevents the loss of protein function. Biochemical analyses of ribonuclease, lysozyme, bovine serum albumin, and ubiquitin provided insight into the damaging effects of glucose modifications on protein func...
The worldwide and continuous reception of Lessings play Nathan the Wise (1779) is an acknowledged phenomenon in German literary studies. Despite its many interpretations, little attention has so far been paid to the plays political implications and how these are politicized. Naturally, a political interpretation gains more importance in times of polarization when a theater staging can potentially have a more influential outlook on politics. In 1779, Nathan the Wise referred to the conflict between German Jews and Christians, who considered themselves religiously superior. To overcome this hierarchy, Lessing draws a tolerant society based on the common values of all three monotheistic creeds. But Lessing was far ahead of his anti-Semitic time and his piece was condemned as heresy against Christianity. In 1933, when Hitler seized power, ...
This thesis focuses on comparing the effects of university technology commercialization practices on their licensing incomes. "High Output" and "High Activity" universities were selected from top U.S. research universities based on the level of resources that are invested in the technology transfer process, as opposed to the level of income generated as
a result of licensing activities. We use the multiple case study method,consisting of four "High Outcome" and four "High Activity" universities. The principles of real options theory are used to compare and contrast the
technology commercialization processes of the two groups, based on the premise that universities that employ a real options perspective in their technology transfer decisions, will have greater licensing incomes. Based on interviews with technology transfer directors at ...
This project explored the predictive relations of depressive disorders with anxiety, externalizing, and substance use disorders. These relations were examined in both directions (i.e., odds of depression given prior anxiety; odds of anxiety given prior depression). Participants were 240 children assessed for psychopathology in sixth grade and then annually through 12th grade. Adolescents varied in risk for depression based on their mothers having a history of depressive disorders (high-risk, n=185) or no history of psychiatric diagnoses (low risk, n=55). For girls, the rates of depressive disorders were high regardless of prior anxiety disorders, whereas for boys, those with prior anxiety were more than three times as likely to have subsequent depression compared to boys with no prior anxiety, controlling for risk (OR = 3.33, p <.05). ...
