Doctor of Philosophy

dissertationThe explosion in computing power and its application to complex multiphysics problems has led to the emergence of computer simulation as a new way of extending the inductive methods of science. Many fields, particularly combustion, have been greatly changed by the ability of simulation to explore in great detail the implications of theories. But problems have also arisen; a philosophical foundation for establishing belief in simulation predictions, particularly important for complex multiphysics systems where experimental data are sparse, is sorely lacking. Toward the end of establishing such a foundation, a comprehensive philosophical approach to model validation, called instrumentalism, is proposed. A framework for verification and validation/uncertainty quantification (V&V/UQ) of codes is presented in detail, and is applied to a novel entrained flow coal gasification model implemented in the massively parallel simulation tool Arches. The V&V/UQ process begins at the mathematical model. The novel coal gasification model, which utilizes the direct quadrature method of moments (DQMOM) for the solid phase and large eddy simulation (LES) for the gas phase and accounts for coupling between the gas and solid phases, is described in detail. A verification methodology is presented in the larger context of validation and uncertainty quantification, and applied to the Arches coal gasification model. A six-step validation framework is adopted from the literature and applied to the validation of the Arches gasification model. One important aspect of this framework is model reduction, creating surrogate models for complex and expensive multiphysics simulators. A procedure for constructing surrogate response surface models is applied to the Arches gasification model, with several statistical analysis techniques used to determine the goodness of fit of the coal gasification response surface. This response surface is then analyzed using two methods: the Data Collaboration methodology, an approach from the literature; and a Monte Carlo analysis of the response surface. These analyses elucidate regions of parameter space where the simulation tool makes valid predictions. The Monte Carlo analysis also yields probabilities of simulation validity, given input parameter values. These probabilities are used to construct a prediction interval, which can then be used to compute the probability of a consistent simulation prediction

The Ursinus Weekly, October 27, 1947

Thespians to stage New York success • Sophs plan dances, class doggie roast • Gen. Arnold makes demand for greater accent on sciences in college curricula • AVC appoints leaders; starts campus clean-up • Ye good olde days in prospect again as school spirit re-appears on campus • Legal society fetes new members; Vice-president Helfferich speaks • May queen to be selected early this semester, Nov. 6 • Gym construction near end; plans for interior finished • Beardwood chemical group elects Pfeiffer president • Reporters added to staff; Lois Cain new sports assistant • Y commission slate opens with discussions, address • New Spanish Club elects officers • Dorms vote to fill WSGA berths • Pre-meds to hear psychiatrist • Aid for Europe? • Grizzlies to play host to victory-hungry PMC • Soccer team bows to Rutgers \u2711\u27, 6-2 • Three teams tied for first in campus football league • Swarthmore interception sets up tally; first frame score gives Garnet 7-0 win • JV hockey team tops Moravian • JV booters thump Hill School • Snell\u27s belles win third straight, 6-1 • Dr. Child addresses English Club • German Club organizes for 1947 • French Club plans activities • New FTA members to be inductedhttps://digitalcommons.ursinus.edu/weekly/1624/thumbnail.jp

Reviews

Introduction to the Law of Employment, Industrial Relations: a Social Psychological Approach, New Zealand and the World: Essays in Honour of Wolfgang Rosenberg, Studies in Conflict: Cases in New Zealand Industrial Relations, Labour Market Economics, The Changing Contours of British Industrial Relations, Workers' Co-operatives: Jobs and Dreams, The Right to Strike, Work and People - an Economic Evaluation of Job Enrichmen

The aggregatibacter actinomycetemcomitans heat shock protein GroEL interacts directly with human peripheral blood T cells

Heat shock family protein GroEL of Aggregatibacter actinomycetemcomitans (Aa) has antigenic properties. We previously demonstrated that A. actinomycetemcomitans GroEL-like protein affects human CD4 T cells by converting them into IL-10 and IFNg double cytokine producing Tbet+ Th1 cells. The objective of this study was to investigate whether or not AaGroEL communicates with T cells directly. To do this, sorted cells from peripheral blood mononuclear cells were stimulated with AaGroEL for 48 h. Flow cytometry was used to measure soluble and intracellular cytokine expression in the cell cultures and detect TLR2 expression on the surface of T cells. Expression of six different soluble cytokines was evaluated by CBA assay. To determine whether AaGroEL affects CD3+ T cells directly or not, purified CD3+ T cells or CD14+ cells were cultured with AaGroEL separately, and the quantity of soluble cytokine was measured. Results showed that sorted CD3+ cells produced soluble IL-6, TNFα-and IFNγ cytokines. Additionally, the intracellular cytokine staining data showed that AaGroEL-stimulated CD3+ cells were also TNFα-and IFNγ-positive. Moreover, AaGroEL-responsive T cells slightly increased their TLR2 expression. These findings suggest that CD3+ T cells produce cytokines in response to AaGroEL protein without requirements for other cells, such as CD14+ monocytes.Scientific and Technological Research Council of Turkey (TUBITAK 106T417

Global Health and Food Security in Fragile and Conflict Affected States (FCAS): Syrian Academics and their Role in the Future of Food Security for Syria

The ongoing conflict in Syria has led to distortions in agriculture, food production and availability, distribution and consumption, with attendant effects on food insecurity and malnutrition. Uncertainties about and/or absence of governance, weakened institutions, changing donor funding priorities/involvement and diminished local research capacity constrain traditional opportunities for long-term contingency planning and access to and integration of local expertise that is essential for timely, evidence-based decision-making. The extensive loss of human and intellectual capital in Syria, as academics are displaced from high-risk areas, as a matter of safety and security, means that the pipeline of expertise necessary for future societal rebuilding efforts is narrow and fragile and requires attention. A Round Table (RT) meeting was held in June 2019 to provide a platform for Syrian academics in exile in Turkey to share their expertise and to initiate a discussion about transition strategies away from short-term emergency aid to long-term food and health security with other researchers, relevant decision-makers, international and local (including Syrian) NGOs and responders to the crisis. This resulted in a number of outcomes: – Creation of a nascent network of expertise exploring the question of transition and long-term contingency planning for food and health security in Syria. – Strengthened and extended partnerships between researchers, practitioners and decision-makers in the UK, Syria and countries in the region receiving Syrian academics in exile (primarily Turkey). – A provisional framework for an expert information ecosystem to incorporate local cultural and technical expertise into future Syrian socio-economic development and reconstruction programmes. This includes the development of repositories to house and curate a catalogue of expertise, data and ongoing research outputs, and funding opportunities. – Identification of an important role for knowledge broker organisations at the interface between researchers, decision-makers and practitioners to ensure knowledge mobilisation across different organisational and disciplinary boundaries

Femtosecond gas phase electron diffraction with MeV electrons

We present results on ultrafast gas electron diffraction (UGED) experiments with femtosecond resolution using the MeV electron gun at SLAC National Accelerator Laboratory. UGED is a promising method to investigate molecular dynamics in the gas phase because electron pulses can probe the structure with a high spatial resolution. Until recently, however, it was not possible for UGED to reach the relevant timescale for the motion of the nuclei during a molecular reaction. Using MeV electron pulses has allowed us to overcome the main challenges in reaching femtosecond resolution, namely delivering short electron pulses on a gas target, overcoming the effect of velocity mismatch between pump laser pulses and the probe electron pulses, and maintaining a low timing jitter. At electron kinetic energies above 3 MeV, the velocity mismatch between laser and electron pulses becomes negligible. The relativistic electrons are also less susceptible to temporal broadening due to the Coulomb force. One of the challenges of diffraction with relativistic electrons is that the small de Broglie wavelength results in very small diffraction angles. In this paper we describe the new setup and its characterization, including capturing static diffraction patterns of molecules in the gas phase, finding time-zero with sub-picosecond accuracy and first time-resolved diffraction experiments. The new device can achieve a temporal resolution of 100 fs root-mean-square, and sub-angstrom spatial resolution. The collimation of the beam is sufficient to measure the diffraction pattern, and the transverse coherence is on the order of 2 nm. Currently, the temporal resolution is limited both by the pulse duration of the electron pulse on target and by the timing jitter, while the spatial resolution is limited by the average electron beam current and the signal-to-noise ratio of the detection system. We also discuss plans for improving both the temporal resolution and the spatial resolution

Femtosecond gas phase electron diffraction with MeV electrons

We present results on ultrafast gas electron diffraction (UGED) experiments with femtosecond resolution using the MeV electron gun at SLAC National Accelerator Laboratory. UGED is a promising method to investigate molecular dynamics in the gas phase because electron pulses can probe the structure with a high spatial resolution. Until recently, however, it was not possible for UGED to reach the relevant timescale for the motion of the nuclei during a molecular reaction. Using MeV electron pulses has allowed us to overcome the main challenges in reaching femtosecond resolution, namely delivering short electron pulses on a gas target, overcoming the effect of velocity mismatch between pump laser pulses and the probe electron pulses, and maintaining a low timing jitter. At electron kinetic energies above 3 MeV, the velocity mismatch between laser and electron pulses becomes negligible. The relativistic electrons are also less susceptible to temporal broadening due to the Coulomb force. One of the challenges of diffraction with relativistic electrons is that the small de Broglie wavelength results in very small diffraction angles. In this paper we describe the new setup and its characterization, including capturing static diffraction patterns of molecules in the gas phase, finding time-zero with sub-picosecond accuracy and first time-resolved diffraction experiments. The new device can achieve a temporal resolution of 100 fs root-mean-square, and sub-angstrom spatial resolution. The collimation of the beam is sufficient to measure the diffraction pattern, and the transverse coherence is on the order of 2 nm. Currently, the temporal resolution is limited both by the pulse duration of the electron pulse on target and by the timing jitter, while the spatial resolution is limited by the average electron beam current and the signal-to-noise ratio of the detection system. We also discuss plans for improving both the temporal resolution and the spatial resolution

Integrating plant- and animal-based perspectives for more effective restoration of biodiversity

Ecological restoration of modified and degraded landscapes is an important challenge for the 21st century, with potential for major gains in the recovery of biodiversity. However, there is a general lack of agreement between plant- and animal-based approaches to restoration, both in theory and practice. Here, we review these approaches, identify limitations from failing to effectively integrate their different perspectives, and suggest ways to improve outcomes for biodiversity recovery in agricultural landscapes. We highlight the need to strengthen collaboration between plant and animal ecologists, to overcome disciplinary and cultural differences, and to achieve a more unified approach to restoration ecology. Explicit consideration of key ecosystem functions, the need to plan at multiple spatial and temporal scales, and the importance of plant–animal interactions can provide a bridge between plant- and animal-based methods. A systematic approach to restoration planning is critical to achieving effective biodiversity outcomes while meeting long-term social and economic needs