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A Quantitative Investigation of the Relationship between Technology Transfer Outreach Programs and Innovation Output at U.S. Research Universities
Get PDFUniversity administrators regard technology transfer as their "Third Mission," because they benefit from more than a billion dollars in annual revenue stream through technology transfer operations. Technology transfer (TT) is the process by which research intensive universities transfer scientific innovations from an academic institution to companies and receive financial compensations. Although innovator engagement is a critical step towards encouraging innovation output, universities have not paid much attention to outreach programs. While a large body of literature has focused on downstream value-creation of commercialization, it has neglected to investigate the upstream innovation-creation process resulting in limited insights. The purpose of this research study was to build upon work engagement theory and multi-perspective models to investigate the relationship between TT outreach programs and innovation output at U.S. research universities. The research design included a quantitative internet survey method involving 163 U.S. research universities and 223 innovators. Data from the survey were analyzed using inferential statistics and IBM SPSS quantitative software to investigate the relationship and explore innovator engagement phenomenon. By identifying preferred training programs and communication channels, recognition and reward systems, and innovation output, this study aims to inform and guide university officials on effective outreach programs preferred from the perspectives of innovators and TT professionals. The findings indicated innovation output is associated with TT outreach programs. Experienced innovators preferred one-on-one interactions with TT offices to address their specific concerns and utilized up-to-date websites with searchable database at their conveniences. Innovators also expressed time constraint to innovate. Although TTOs recognized face-to-face interaction is an effective channel, budget constraint to have enough work force to manage such interactions is a challenge. Both innovators and TTOs indicated university administrators needed to include TT activities in the promotion and tenure consideration. In conclusion, outreach programs have the potential to increase innovation output for novice innovators that include students. University administrators should consider faculty's technology transfer accomplishments as academic achievements and allow time for faculty to innovate.Ed.D., Educational Leadership and Management -- Drexel University, 201
In the Wake of Hoffman: Psychologist and Public Perceptions of the Role of Psychologists in National Security Interrogations and Other Non-Traditional Settings
Get PDFThe purpose of this study was to examine the opinions of the general public and psychologists regarding the roles of psychologists in national security interrogations and other contexts that do not involve the delivery of traditional assessment and treatment services. The discussion following the release of the Hoffman Report has underscored the sharp differences in how the Report’s findings are regarded. This survey of psychologists engaged in traditional and non-traditional professional activities, as well as the general public, sheds light on the broader perceptions of the Report’s conclusions and implications, and helps determine future directions for the profession of psychology. Results revealed that the general public appears to be more accepting of psychologist involvement in national security settings – the type of activities highlighted in the Report as problematic – than psychologists. In addition, findings demonstrated that the perceptions of traditional and non-traditional psychologists regarding the appropriate role of psychologists across myriad settings do not differ significantly, perhaps indicating that the profession is less divided than initially thought after the Report’s release. Implications for research, policy, and practice are discussed.M.S., Psychology -- Drexel University, 201
Structural, Thermodynamic and Photo-Physical Properties of Cesium Lead Halide Perovskites
No full textRecently, the emergence of metal halide perovskite solar cells as a contender for next-generation photovoltaics constitutes a paradigm shift in the field of solution-processed semiconductors. Increased understanding of the fundamental optoelectronic, and structural properties of these materials and advances in thin film processing over the last few years have led to a meteoric rise in power conversion efficiencies, exceeding 23%, now rivaling much more mature commercial technologies. While the vast majority of halide perovskite studies involve the prototypical organic-inorganic hybrid compound methylammonium lead iodide (MAPbI3), the volatile and hygroscopic organic cation is detrimental to its chemical stability. Thus, finding an alternative material system, which can mitigate these issues without diminishing the desirable optoelectronic properties, is necessary. This thesis focuses on understanding the thermodynamic and photo-physical properties of a promising all-inorganic alternative, perovskite-phase cesium lead iodide (CsPbI3). The perovskite ('black') phase of CsPbI3 spontaneously forms at elevated temperature (>320 °C). At room temperature (ambient condition) the thermodynamically favored phase is a non-perovskite structure ('yellow'), not useful for photovoltaic application. To develop a fundamental understanding of phase transitions in CsPbI3, and quantify the thermodynamic landscape of phase change, herein spectroscopy and calorimetry techniques have been employed. A reversible enthalpy difference of 14.2 (± 0.5) kJ/mol between the two phases is observed which is offset only by the similarly large entropic favorability of the desired phase. It has also been shown that by rapid cooling (quenching) the black phase of CsPbI3 can be kinetically trapped in a metastable state. It is demonstrated herein that the mechanistic role of atmospheric moisture in the phase transition is catalytic rather than enthalpic. These fundamental physicochemical insights are implemented to design stable derivatives. To enhance the phase stability of the black-CsPbI3 towards atmospheric moisture a chloride doping strategy has been devised and implemented herein. The conventional synthetic routes do not allow a significant amount of chloride doping due to limited miscibility of chloride in a CsPbI3 host lattice. A combined solution- and solid-state method has been adopted. Colloidal nanocrystals of pure CsPbCl3 and CsPbI3 are co-deposited and the resulting nanocrystal solid is subsequently fused into a polycrystalline thin film of CsPbI3-xClx by chemically-induced, room-temperature sintering. This approach ensures nanometer-scale mixing even at compositions that potentially exceed the bulk miscibility of the two phases. From theoretical calculations an atomistic insight into the formation of the mixed crystal phase has been obtained. In order to accept CsPbI3 as an alternative to MAPbI3, the optoelectronic parameters need to be comparable. Transient Absorption Spectroscopy (TA) and Time Resolved Terahertz Spectroscopy have been employed to reveal the recombination kinetics of CsPbI3. By developing a 1D finite difference diffusion-recombination model the recombination rate constants are estimated and the role of carrier diffusion deconvoluted. A nearly identical bimolecular rate constant, a fundamental property of the semiconducting materials, between CsPbI3 the most highly optimized MAPbI3 films in the literature has been observed. Such resemblance without the presence of molecular dipole infers that the organic cation does not provide any fundamental advantage in the slow radiative recombination kinetics of the hybrid perovskites.Ph.D., Chemical Engineering -- Drexel University, 201
The Role of Fan-Subtitle Groups in the Process of Introducing US Television Programs Into China: A Case Study
Get PDFTelevision programs as an important cultural carrier have played a significant role in cross-cultural communication between China and the United States. This thesis will first focus on the television products that have been used as a bridge in cross-cultural communication. It will then discuss the different stages of the introduction of US television programs in China, especially the current stage - Fansub groups. This study gathers data through personal interviews and an online survey. The survey was conducted online, through multiple Chinese social media. The researcher used Chinese online questionnaire software "Wenjuan Wang" to collect data and organize the information. The purpose of the study was to explore the influence of Fansub groups on the Chinese television industry and society. This research aims to explore both the status quo of Fansub groups as they exist on the edge of the legitimate business world and the impact of their work as a carrier of cross-cultural communication in Chinese society. Therefore, this study hopes to illuminate the areas where Fansub groups may potentially become a legitimate player in the market.M.S., Television Management -- Drexel University, 201
Inflated Weight, a Dual Approach to Structure Constants for K-Theory of Grassmannians, and a Charge Statistic for Shifted Tableaux
No full textThe problem of computing products of Schubert classes in the cohomology ring can be formulated as the problem of expanding skew Schur polynomials into the basis of ordinary Schur polynomials. In contrast, the problem of computing the structure constants of the Grothendieck ring of a Grassmannian variety with respect to its basis of Schubert structure sheaves is not equivalent to expanding skew stable Grothendieck polynomials into the basis of ordinary stable Grothendiecks. Instead, we show that the appropriate K-theoretic analogy is through the expansion of skew reverse plane partitions into the basis of polynomials which are Hopf-dual to stable Grothendieck polynomials. We combinatorially prove this expansion is determined by Yamanouchi set-valued tableaux. A by-product of our results is a dual approach proof for Buch's K-theoretic Littlewood-Richardson rule for the product of stable Grothendieck polynomials. Additionally we answer a question posed by Wan and Wang in 2011. The Kostka-Foulkes polynomials are ubiquitous in algebraic combinatorics, geometry, and representation theory. These polynomials in a parameter t with positive coefficients have deep connections to the Springer theory of Weyl group representations and Lusztig's q-weight multiplicity in finite dimensional irreducible representations of the general linear Lie algebra, among other things. Lascoux and Schutzenberger provided an elegant description of the Kostka-Foulkes polynomials in terms of charge, a statistic associated to Young tableaux. Wan and Wang introduced a spin counterpart, the spin Kostka polynomials, and asked that they be given a Lascoux and Schutzenberger type description by a statistic on shifted Young tableaux. The spin charge statistic given here fulfills this request.Ph.D., Mathematics -- Drexel University, 201
How School Leadership Fosters or Constrains the Development of a Creative Learning Culture
No full textIn times of constant change, providing students with opportunities to develop critical 21st century skills of creativity and innovation, becomes an important responsibility of our school systems. Development of these learning opportunities requires skilled and creative leadership. Leaders who have the characteristics necessary to transform a school culture through their own creative influence are the motivation for this research. Creative leadership's influence on the formation and sustainability of a school learning culture is detailed from the perspective of teachers, informal leaders, and formal leaders within the culture. Using data collected through in-depth interviewing, focus groups, and a teacher perception questionnaire, the study offers an in-depth look at influences creative leadership has on the beliefs, attitudes, and actions of those within one public middle school culture. This inside view offers understanding of how creative leadership may foster the type of learning culture necessary for the growth and development of students ready for the challenges of a progressive world. Findings reveal a reciprocal relationship between creative leadership and creative school culture. The study offers explanation of how beliefs, attitudes, and actions of a school leader may influence teacher creativity. The personal perspectives of the participants in this case study may offer general theories or suggested courses of action for new or current school leaders seeking to cultivate a similar culture within their own school environment. Study recommendations for administrative training and professional development include topics focused on the development of the leadership traits of creativity and innovative mindset.Ed.D., Educational Leadership and Management -- Drexel University, 201
Impact of Apparent Treatment Resistant Hypertension on Cardiovascular Disease and Potential Biological and Pharmaceutical Interactions
No full textApparent Treatment Resistant Hypertension (ATRH) is a growing and serious concern in the U.S. affecting approximately 13% of hypertensive adults. Uncontrolled blood pressure has been connected to adverse health outcomes; however, little has been researched on long-term prognosis of individuals with ATRH. It is unclear how the relationship between ATRH and CVD would be modified by differing biological/demographic factors (age, sex, obesity, and diabetes), and first-line antihypertensive medications (diuretic, calcium channel blocker, and ACE inhibitor). Data was obtained from the Antihypertensive and Lipid Lowering to Prevent Heart Attack Trial (ALLHAT, N = 25,516) was used and ATRH was assessed from the year 2 follow-up visit (N = 2,329). Cox Proportional Hazards models were used to analyze the relationship between ATRH and CVD. Two-way interactions were analyzed (modifier*ATRH) and results suggested which three-way interactions to test (modifier*modifier*ATRH). Effect modification on the multiplicative scale and additive scale was assessed through use of product terms in the Cox model, heterogeneity of effects, and joint effects. CVD event was the outcome (N=5,030) of interest. ATRH was associated with a 30% increase in risk of CVD (HR 1.3 95% CI 1.19-1.42). Sex and age were found to modify the relationship of ATRH and CVD on both scales. Among women, ATRH was associated with a 62% increase in risk of CVD event (95% CI 1.41 - 1.86) while among men, ATRH was associated with a 14% increase in risk of CVD (95% CI 1.01 - 1.28). ATRH had a stronger impact on risk of CVD among younger subjects than it did among older (HR 1.55, 95% CI 1.33 - 1.79 and HR 1.18, 95% CI 1.05 - 1.32 respectively). No significant two-way effect modification by drug class was observed on either the multiplicative or additive scale. Potential three-way interaction was observed for both ATRH*Sex*Age and ATRH*Sex*Drug. The observed joint effect of being male, with ATRH, and on Lisinopril or Amlodipine on CVD risk (HR 1.39, 95% CI 0.73 - 2.06 and HR 1.55, 95% CI 0.87 - 2.22 respectively) was less than what was expected for both the multiplicative and additive models. The observed joint effect of being male, with ATRH and 65 years or older (HR 1.85, 95% CI 1.22 - 2.48) was less than what was expected for both additive and multiplicative models (HRs 4.10, 95% CI 3.63 - 4.57 and 4.88, 95% CI 3.66 - 6.31 respectively). The sub-multiplicative two-way interaction with ATRH*sex was a main driver in both observed three-way interactions. Our findings indicate that patient sex should be taken into consideration when considering ways to improve awareness, diagnosis, treatment, and management of ATRH. Future research should focus on these observed gender differences in patient outcomes with ATRH with specific focus on the underlying mechanisms at play in this relationship.Ph.D., Epidemiology -- Drexel University, 201
Block Black Box Algorithms Over Small Fields
No full textBlack box linear algebra algorithms treat matrices as black boxes that can be applied to input vectors but whose elements cannot be accessed or modified. Since they avoid the fill-in of non-zero entries that occurs with elimination based approaches, black box algorithms provide an efficient approach to computing with sparse matrices and can be used to compute matrix invariants such as minimal polynomial, characteristic polynomial, rank, determinant, and Frobenius normal form for very large sparse matrices over finite fields. Many of these algorithms are probabilistic and often require preconditioning to ensure certain properties hold with high probability. To guarantee a high probability of success it is often necessary that the underlying field contain a large number of elements. Consequently, when computing over small fields, such as GF(2), which is the case for many important applications, these algorithms may require computation over an extension field or repeated computation. This can lead to a significant slow down in practice. Block black box algorithms, such as the block Wiedemann algorithm, which apply black box matrices simultaneously to blocks of input vectors, have been developed for linear system solving. Block algorithms improve performance through better data locality and parallelism and can avoid the need for repeated computation or the use of extension fields needed by approaches without blocking. In this thesis, adaptations of the block Wiedemann algorithm for computing minimal polynomial, characteristic polynomial, rank, determinant, and Frobenius normal form over finite fields, especially small fields, are designed, implemented, analyzed and compared to existing implementations in the LinBox linear algebra library. The key algorithm, LIFs, uses the block Wiedemann algorithm to compute the largest invariant factors of a matrix. A tight probability bound is obtained showing that, with high probability, LIFs correctly computes the r largest invariant factors, even for small fields, using a block size slightly larger than r. An efficient implementation of LIFs requires fast computation of the Smith normal form (SNF) of a polynomial matrix over a finite field. This thesis compares a variety of SNF algorithms and provides an efficient implementation appropriate for use in LIFs. When LIFs is able to compute all of the invariant factors then it can be used to compute minimum polynomial, rank, determinant, characteristic polynomial and Frobenius normal form significantly faster, for matrices over small fields, than existing approaches based on the scalar Wiedemann algorithm with various preconditioners. When there are a large number of invariant factors LIFs cannot be used directly. For rank and determinant computation heuristic preconditioners are used to produce equivalent matrices with a small number of invariant factors for which LIFs can be used. For characterstic polynomial and Frobenius normal form LIFs is used iteratively and for small fields, even when a relatively large block size is needed, the iterated LIFs algorithm outperforms existing approaches. When very large block sizes are needed a new approach for Frobenius form computation based on repeated rank computation is outlined and experiments show it to be promising compared to general black box algorithms for Frobenius normal form.Ph.D., Computer Science -- Drexel University, 201
Restoring Tip60 HAT/HDAC2 Balance in the Neurodegenerative Brain Promotes Neural Health
No full textEpigenetic gene control in the brain is a fundamental mechanism for orchestrating dynamic gene expression profiles critical for cognitive function. One of the best characterized epigenetic mark crucial for learning and memory is histone acetylation that regulates cognitive gene expression by controlling chromatin packaging in neurons. Appropriate histone acetylation homeostasis is maintained by the antagonistic activity of histone acetyltransferases (HATs) and histone deacetylases (HDACs). Numerous studies, including studies from our lab, have shown that disruption of this finely tuned epigenetic balance in the brain involving reduced histone acetylation levels causes an epigenetic blockade of transcription with concomitant cognitive impairment that is a key step in neurodegenerative disease etiology including Alzheimer’s disease (AD). Nevertheless, the specific HATs that generate these neuroepigenetic marks, the gene profiles they regulate, and their mechanisms of action in neural epigenetic gene control in the brain remain largely unknown. Here, we show that disruption of Tip60 HAT/HDAC2 homeostasis occurs early in the brain of an AD associated amyloid precursor protein (APP) Drosophila model and triggers epigenetic repression of neuroplasticity genes well before A[beta] plaques form. Repressed genes display enhanced HDAC2 binding and reduced Tip60 and histone acetylation enrichment. Increasing Tip60 in the AD associated APP brain restores Tip60 HAT/HDAC2 balance by decreasing HDAC2 levels, reverses neuroepigenetic alterations to activate synaptic plasticity genes, and reinstates brain morphology and cognition. Such Drosophila neuroplasticity gene epigenetic signatures are conserved in male and female mouse hippocampus and their expression and Tip60 function is compromised in hippocampus from AD patients. These findings indicate that Tip60 HAT/HDAC2 mediated epigenetic gene disruption is a critical initial step in AD that is reversed by restoring Tip60 in the brain. However, whether such a mechanism is specific to AD or common to other neurodegenerative conditions remains to be identified. Here, we show that disruption of Tip60 HAT/HDAC2 balance is an early event in multiple neurodegenerative Drosophila models including Huntington’s Disease (HD), Amyotrophic Lateral Sclerosis (ALS) and Parkinson’s Disease (PD) and triggers epigenetic repression of certain subset of synaptic plasticity genes early in the disease. Moreover, larval olfactory associative learning assay displayed significant defects in the learning and memory function, as well as defects in locomotor abilities under neurodegenerative conditions. Importantly, increasing Tip60 HAT activity specifically in the mushroom body of the disease larvae restores defects in complex behaviors including learning and memory and locomotion. Our results support a model by which Tip60 HAT/HDAC2 mediated epigenetic control is critical for normal cognitive function and its disruption is an early event in most neurodegenerative disorders. These studies helped us determine whether Tip60 protects against different neurological impairments via similar modes of action. Our results lay the groundwork for discovering a potentially broad neuroprotective role for Tip60 HAT action in multiple neurological disorders.Ph.D., Biological Sciences -- Drexel University, 201
On the Durability of Bonded Repairs to Fuselage Structures Subjected to Mechanical and Environmental Conditions
No full textBonded repair is one of the structural repair technologies that the aircraft industry uses to restore the strength of fuselage structures and increase the life of an aircraft. Bonded repairs are superior to the conventional metallic fastened repairs in that the former yield a higher stiffness and lower stress concentrations and are more aerodynamically and structurally efficient. Bonded repair technology has been used to repair military aircraft for over three decades but has not been certified for repairing commercial aircraft due to the lack of sufficient performance data to support their airworthiness. Experimental work and analytical modeling of bonded repairs have also been limited to those of flat coupon specimen under ambient environmental conditions. In this study, experimental and analytical work on a full-scale curved fuselage panel with various bonded repairs is conducted to investigate their durability and integrity. The experimental work was carried out using the Federal Aviation Administration's Full-Scale Aircraft Structural Test Evaluation and Research fixture. The objectives are to characterize the durability and fatigue performance of boron/epoxy (B/Ep) and aluminum bonded repairs under a simulated service load condition over the design service life of the airplane and to investigate tools for evaluating and monitoring the repair integrity over the life of the part. During all test phases, damage formation and growth of cracks and disbonds were monitored and recorded using a structural health monitoring system and several nondestructive inspection methods. In addition, strains in the vicinity of the repair patches were continuously recording using strain gages and the digital image correlation method. Experimental results indicated that the bonded repairs are effective to reduce the fatigue crack growth rate. A linear elastic fracture mechanics based analytical model is developed to predict the growth rates of fatigue cracks in the curved panel repaired by bonded patches. The unique feature of this model is that, by using a fuselage-dependent geometric correction factor and incorporating the bonded repair theory, this model can be applied to predict the growth of a crack under any type of bonded repair in a given fuselage. The model has been validated by comparing the predicted crack growth rate results with that obtained experimentally.Ph.D., Mechanical Engineering and Mechanics -- Drexel University, 201