Indiana University-Purdue University Indianapolis (IUPUI) / We numerically investigate the underlying physics of two peculiar phenomena, which are axis-switching and saddle-back velocity profile, in both laminar and turbulent rectangular jets using lattice Boltzmann method (LBM). Previously developed computation protocols based on single-relaxation-time (SRT) and multiple-relaxation-time (MRT) lattice Boltzmann equations are utilized to perform direct numerical simulation (DNS) and large eddy simulation (LES) respectively. In the first study, we systematically study the axis-switching behavior in low aspect-ratio (AR), defined as the ratio of width over height, laminar rectangular jets with <italic>AR=1</italic> (square jet), 1.5, 2, 2.5, and 3. Focuses are on various flow properties on transverse planes downstream to investigate the correlation between the streamwise velocity and secondary flow. Three distinct regions of jet development are identified in all the five jets. The <italic>45&deg</italic> and <italic>90&deg</italic> axis-switching occur in characteristic decay (CD) region consecutively at the early and late stage. The half-width contour (HWC) reveals that <italic>45&deg</italic> axis-switching is mainly contributed by the corner effect, whereas the aspect-ratio (elliptic) feature affects the shape of the jet when <italic>45&deg</italic> axis-switching occurs. The close examinations of flow pattern and vorticity contour, as well as the correlation between streamwise velocity and vorticity, indicate that <italic>90&deg</italic> axis-switching results from boundary effect. Specific flow patterns for <italic>45&deg</italic> and <italic>90&deg</italic> axis-switching reveal the mechanism of the two types of axis-switching respectively. In the second study we develop an algorithm to generate a turbulent velocity field for the boundary condition at jet inlet. The turbulent velocity field satisfies incompressible continuity equation with prescribed energy spectrum in wave space. Application study of the turbulent velocity profile is on two turbulent jets with <italic>Re=25900</italic>. In the jets with <italic>AR=1.5</italic>, axis-switching phenomenon driven by the turbulent inlet velocity is more profound and in better agreement with experimental examination over the laminar counterpart. Characteristic jet development driven by both laminar and turbulent inlet velocity profile in square jet (<italic>AR=1</italic>) is also examined. Overall agreement of selected jet features is good, while quantitative match for the turbulence intensity profiles is yet to be obtained in future study. In the third study, we analyze the saddle-back velocity profile phenomenon in turbulent rectangular jets with AR ranging from 2 to 6 driven by the developed turbulent inlet velocity profiles with different turbulence intensity (<italic>I</italic>). Saddle-back velocity profile is observed in all jets. It has been noted that the saddle-back's peak velocities are resulted from the local minimum mixing intensity. Peak-center difference <italic>&Delta_pc</italic> and profound saddle-back (PSB) range are defined to quantify the saddle-back level and the effects of AR and <italic>I</italic> on saddle-back profile. It is found that saddle-back is more profound with larger AR or slimmer rectangular jets, while its relation with <italic>I</italic> is to be further determined.

Indiana University-Purdue University Indianapolis (IUPUI) / The sympathetic nervous system strongly modulates the contractile and electrical function of the heart. The anatomical underpinnings that enable a spatially and temporally coordinated dissemination of sympathetic signals within the cardiac tissue are only incompletely characterized. In this work we took the first step of unraveling the in situ 3D microarchitecture of the cardiac sympathetic nervous system. Using a combination of two-photon excitation fluorescence microscopy and computer-assisted image analyses, we reconstructed the sympathetic network in a portion of the left ventricular epicardium from adult transgenic mice expressing a fluorescent reporter protein in all peripheral sympathetic neurons. The reconstruction revealed several organizational principles of the local sympathetic tree that synergize to enable a coordinated and efficient signal transfer to the target tissue. First, synaptic boutons are aligned with high density along much of axon-cell contacts. Second, axon segments are oriented parallel to the main, i.e., longitudinal, axes of their apposed cardiomyocytes, optimizing the frequency of transmitter release sites per axon/per cardiomyocyte. Third, the local network was partitioned into branched and/or looped sub-trees which extended both radially and tangentially through the image volume. Fourth, sub-trees arrange to not much overlap, giving rise to multiple annexed innervation domains of variable complexity and configuration. The sympathetic network in the epicardial border zone of a chronic myocardial infarction was observed to undergo substantive remodeling, which included almost complete loss of fibers at depths >10 µm from the surface, spatially heterogeneous gain of axons, irregularly shaped synaptic boutons, and formation of axonal plexuses composed of nested loops of variable length. In conclusion, we provide, to the best of our knowledge, the first in situ 3D reconstruction of the local cardiac sympathetic network in normal and injured mammalian myocardium. Mapping the sympathetic network connectivity will aid in elucidating its role in sympathetic signal transmisson and processing.

Indiana University-Purdue University Indianapolis (IUPUI) / Stroke is the main cause of disability in the United States. Individuals with stroke commonly report sensory impairment affects their recovery. Motor recovery and sensory impairment are related and impact individuals’ ability to perform valued occupations. Despite the prevalence of sensation impairment after stroke, many occupational therapists fail to include sensation assessment and intervention in treatment planning. The exclusion of sensation in occupational therapy interventions during stroke rehabilitation may be due to the lack of literature supporting the association between sensation and occupational performance. The current study aimed to determine the relationship between touch sensation of the affected hand and occupational performance and satisfaction in individuals with chronic stroke. Using a cross-sectional study design, this study associated factors related to hand sensation and function in individuals with chronic stroke. Fifty individuals with chronic stroke participated in a one-time testing session in which assessments related to sensation, movement of the hand and engagement in daily activities were administered. Correlation analyses were utilized to determine relationships between touch sensation of the affected hand with individuals’ abilities to engage in valued daily activities, arm and hand disability, and manual abilities. The main finding of the study was that individuals with intact sensation reported greater ability to perform valued occupations and satisfaction with their performance, as compared with individuals with touch sensation impairment. For individuals with impaired touch sensation of the affected hand, impairment of touch sensation of the hand did not correlate with individuals’ performance or satisfaction with valued occupations, arm or hand movement, or manual abilities. Collectively, the results of this study reflect the complex interaction between touch sensation, occupational performance, motor functioning, and manual abilities of the affected hand for individuals’ who have experienced a stroke. This study informs therapists, rehabilitation scientists, and other healthcare professionals that client-centered, individualized approaches, including a wide array of clinical assessments and intervention, including assessment of occupational performance and sensation, remain important components in stroke rehabilitation.

Indiana University-Purdue University Indianapolis (IUPUI) / Autophagy is a conserved cellular process that involves sequestration and degradation of cytosolic contents. The cell can engulf autophagic cargo (lipids, long-lived proteins, protein aggregates, and pathogens) through a double bound membrane called an autophagosome that fuses with a lysosome where hydrolases then degrade these contents. This process is one of the main defenses against starvation and is imperative for newborns at birth. Research on this process has increased exponentially in the last decade since its discovery almost a half a century ago. It has been found that autophagy is an important process in many diseases, continues to be at the forefront of research, and is clearly not fully understood. Our preliminary cell culture data in endothelial and epithelial cells show that a blockade of the de novo ceramide synthesis pathway, during treatment with an autophagy stimulus (cigarette smoke extract exposure), does not result in any reduction in autophagy or autophagic flux. Conversely, when acid sphingomyelinase (ASM) is pharmacologically inhibited, which prevents the generation of ceramide from sphingomyelin in an acidic environment, a profound increase in autophagy is observed. In this work, we hypothesize that (ASM) is an endogenous inhibitor of autophagy. ASM has two forms, a secreted form and a lysosomal form. N-terminal processing in the Golgi determines its cellular fate. In the lysosomal form, the phosphodiesterase is bound in the lysosomal membrane. The pharmacological inhibition mechanism is to release ASM from the membrane and allow other hydrolases to actively degrade the enzyme which, in turn, decreases the activity of ASM. This suggests that either the activity of ASM is a regulator of autophagy or that the presence of ASM, activity aside, is required for the lysosomal nutrient sensing machinery (LYNUS) to function properly. Here, we show that ASM is, in fact, an endogenous inhibitor of autophagy in vitro. The phosphorylation status of P70 S6k, a downstream effector of mammalian target of rapamycin (mTOR), which is part of the LYNUS, shows that dissociation of ASM from the membrane regulates mTOR and disturbs the LYNUS in such a manner as to signal autophagy.

Indiana University-Purdue University Indianapolis (IUPUI) / The present study sought to examine the impact of technology in permeating the boundaries between individuals’ work and family domains, testing and extending the current theoretical model of boundary management. The first goal, to explore predictors of the boundary management styles (BMS) people use with respect to communication technology (CT), was accomplished by demonstrating that three factors predicted BMS for CT use: preferences for integration, identity centrality, and work/family norms. The second goal, to examine outcomes that could result from varying CT use boundary management styles, was also supported in that BMS for CT use was a predictor of work-family conflict and enrichment. However, one key component of the model was not supported in that perceived control over BMS did not moderate the relationship between BMS and outcomes. Theoretical and practical implications of these findings are discussed, as well as suggestions for future research on boundary theory and CT use. By exploring tangible boundary management behaviors, the present study offers interesting implications that could ultimately assist organizations in developing policies regarding CT use both at home and at work.

Indiana University-Purdue University Indianapolis (IUPUI) / Neurofibromatosis Type 1 (NF1) is a genetic disorder resulting from mutations in the NF1 tumor suppressor gene. Neurofibromin is the protein product of NF1 and functions as a negative regulator of Ras activity in both hematopoietic and vascular wall cells, which are critical for maintaining blood vessel homeostasis. NF1 patients are predisposed to chronic inflammation and premature cardiovascular disease, including development of large arterial aneurysms, which may result in sudden death secondary to their rupture. However, the molecular pathogenesis of NF1 aneurysm formation is completely unknown. Utilizing a novel model of Nf1 murine aneurysm formation, we demonstrate that heterozygous inactivation of Nf1 (Nf1+/-) results in enhanced aneurysm formation with myeloid cell infiltration and increased reactive oxygen species in the vessel wall. Using cell lineage-restricted transgenic mice, we show that loss of a single Nf1 allele in myeloid cells is sufficient to recapitulate the Nf1+/- aneurysm phenotype in vivo. Additionally, oral administration of simvastatin, a statin with antioxidant and anti-inflammatory effects, significantly reduced aneurysm formation in Nf1+/- mice. Finally, the antioxidant apocynin was administered orally and also resulted in a significant reduction of Nf1+/- aneurysms. These data provide genetic and pharmacologic evidence that neurofibromin-deficient myeloid cells are the central cellular triggers for aneurysm formation in a novel model of NF1 vascular disease, implicated oxidative stress as the key biochemical mechanisms of NF1 aneurysm formation and provide a potential therapeutic target for NF1 vasculopathy.

Indiana University-Purdue University Indianapolis (IUPUI) / Medication administration error remains a leading cause of preventable death. A gap exists in understanding attentional dynamics, such as nurse situation awareness (SA) while managing interruptions during medication administration. The aim was to describe SA during medication administration and interruption handling strategies. A crosssectional, descriptive design was used. Cognitive task analysis (CTA) methods informed analysis of 230 interruptions. Themes were analyzed by SA level. The nature of the stimuli noticed emerged as a Level 1 theme, in contrast to themes of uncertainty, relevance, and expectations (Level 2 themes). Projected or anticipated interventions (Level 3 themes) reflected workload balance between team and patient foregrounds. The prevalence of cognitive time-sharing during the medication administration process was significant or may be remarkable. Findings substantiated the importance of the concept of SA within nursing as well as the contribution of CTA in understanding the cognitive work of nursing during medication administration.

Indiana University-Purdue University Indianapolis (IUPUI) / In recent decades, Petri nets (PNs) have been used to model traffic networks for different purposes, such as signal phase control, routing, and traffic flow estimation, etc. Because of the complex nature of traffic networks where both discrete and continuous dynamics come into play, the Hybrid Petri net (HPN) model becomes an important tool for the modeling and analysis of traffic networks. In Chapter 1 a brief historical summery about traffic systems control and then related work is mentioned followed by the major contributions in this research. Chapter 2 provides a theoretical background on Petri nets. In Chapter 3, we develop a HPN model for a single signalized intersection first, then we extend this model to study a simple traffic network that consists of two successive intersections. Time delays between different points of network are also considered in order to make the model suitable for analysis and simulation. In addition to HPN models, we also consider discrete Petri nets where their modeling simplicity enables the characterization of the occurrences of all events in the system. This discrete PN is particularly useful to give a higher-level representation of the traffic network and study its event occurrences and correlations. In Chapter 4, we build a discrete PN model to represent a traffic network with two successive intersections. However, we find that the model leads to unbounded places which cannot accurately reflect the dynamics of the traffic in terms of event occurrences. Hence, we introduce the Modified Binary Petri nets (MBPN) to overcome the limitation and resolve the confliction problem when we design our controllers. This MBPN model is a powerful tool and can be useful for the modeling and analysis of many other applications in traffic networks. Chapter 5 gives a summary for each chapter, provides conclusion and discusses future work for both discrete and hybrid Petri nets.

Text in English / The membership of the African Independent Churches is growing day by day. Research into the growth ohhis phenomenon is being conducted by various scholars. G.C. Oosthuizen studied the African Independent Churches in general, and the Shembe Church, in particular. This study examines Oosthuizen' s research of the African Independent Churches by analysing the three books that he devoted specifically to the Shembe Church. A set of five criteria is developed to evaluate Oosthuizen as a researcher. The study finds that his background and formation affected the research he conducted and contributed to the type of picture he portrayed of the Shembe Church. Oosthuizen, as a scholar of religion, sometimes allowed his theological interests to influence his research. As an empirical researcher Oosthuizen attempted to let the AICs "speak for themselves" but his theological interests caused him to make value judgements which influenced his research findings. / Christian Spirituality, Church History and Missiology / M. Th. (Missiology)

This thesis is divided into two main parts. The theoretical part defines the concept of self-assessment and focuses on the significance and forms of self-assessment, as well as the factors arising during implementation of self-assessment in education. This part also contains findings from specialized publications analysing the relationship between assessment and self-assessment directed towards individualisation (personalisation). The practical part of this thesis takes the form of pro-active research, the aim of which is to observe implementation of self- assessment by a specific pupil with a specific learning disability. It describes how to teach an integrated pupil to self-assess, confirms that the pupil is able to self-assess his work and describes the steps involved in the implementation. Key words evaluation, self-assessment, pupil with special needs, integrated pupil, descriptive language, evaluation criteria, quality indicator, forms of self-assessment, action research