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Title: Study of ideal dry pipe valve
Creator: Hepp, A. A., Smith, E. J. L.
Date: 2009, 1906
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studyofidealdryp00hepp
Thesis (B.S.)--Armour Institute of Technology

Title: Using Controlled Unsteady Fluid Mass Addition to Enhance Jet Mixing
Creator: Raman, G.
Date: 1997-04
Publisher: American Inst Aeronaut Astronaut
Description: A rectangular jet was excited by controlled unsteady fluid mass addition using two miniature fluidic jets placed on either side of its narrow...
Show moreA rectangular jet was excited by controlled unsteady fluid mass addition using two miniature fluidic jets placed on either side of its narrow dimension. The subharmonic of the primary's preferred jet column frequency [St(D-e) = fD(e)/U-J = 0.15] was forced in the antisymmetric mode because such forcing persists for longer downstream distances than the fundamental. Details of the phase-averaged flowfield, velocity gradient terms, velocity spectra, and the mean and fluctuating flowfields were documented. The fluidically excited mode grew and persisted in the flow beyond the potential core region. Unsteady fluid mass addition of 12% (4% momentum addition) per fluidic jet resulted in a 35% reduction of the potential core length and about a 60% increase in the normalized mass flux (percentages are with reference to the primary unforced jet). On the basis of the results, it appears that fluidic devices have the potential for use in shear flow control applications.
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Title: COMPRESSIVE SENSING AND RECONSTRUCTION : THEORY AND APPLICATIONS
Creator: Krishnamurthy, Ritvik Nadig
Date: 2014, 2014-07
Description: Conventional approach in acquisition and reconstruction of images from frequency domain strictly follow the Nyquist sampling theorem. The...
Show moreConventional approach in acquisition and reconstruction of images from frequency domain strictly follow the Nyquist sampling theorem. The principle states that the sampling frequency required for complete reconstruction of a signal is at least twice the maximum frequency of the original signal. This dissertation studies an emerging theory called Compressive Sensing or Compressive Sampling which goes against the conventional wisdom. Theoretically, it is possible to reconstruct images or signals accurately from a number of samples which is far smaller than the Nyquist samples. Compressive Sensing has proven to have farther implications than merely reducing sampling frequency of the signal. Possibility of new data acquisition methods from analog domain to digital form using fewer sensors, image acquisition using much smaller sensors array, to name a few. This novel theory combines sampling and compression methods thereby reducing the data acquisition resources, such as number of sensors, storage memory for collected samples and maximum operating frequency. This dissertation presents some insights into reconstruction of grey scale images and audio signals using OMP and CoSaMP algorithms. It also delves into some of the key mathematical insights underlying this new theory and explains some of the interactions between Compressive Sensing and related elds such as statistics, coding theory and theoretical computer science. viii
M.S. in Computer Engineering, July 2014
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Title: LOG ANALYSIS FOR RELIABILITY MANAGEMENT IN LARGE-SCALE SYSTEMS
Creator: Zheng, Ziming
Date: 2012-07-16, 2012-07
Description: With the increasing scale and complexity of high performance computing (HPC) systems, reliability management is becoming a major concern....
Show moreWith the increasing scale and complexity of high performance computing (HPC) systems, reliability management is becoming a major concern. System logs are the primary source of information to understand and analyze system problems. Nevertheless, manual log processing is time-consuming, error-prone, and not scalable. Currently little study has been done on automated log analysis for practical use in HPC systems. In this thesis, we present a log analysis infrastructure by exploiting data mining and machine learning technologies. Our work can be broadly divided into four parts: log pre-processing, online failure prediction, automatic root cause diagnosis, and reliability modeling. We evaluate our results by means of system logs collected from production HPC systems. This work can greatly improve our understanding of faults and failures arising from hardware/software components and their interactions. It can further facilitate the reliability management for HPC systems.
Ph.D. in Computer Science, July 2012
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Title: NONLINEAR PREDICTIVE CONTROL OF PERIODICALLY FORCED CHEMICAL REACTORS
Creator: Ozgulsen, F., Kendra, S. J., Cinar, A.
Date: 1993-04
Publisher: AMER INST CHEMICAL ENGINEERS
Description: A nonlinear model-predictive control strategy is developed to maintain the superior-to-steady-state performance of a periodically forced...
Show moreA nonlinear model-predictive control strategy is developed to maintain the superior-to-steady-state performance of a periodically forced chemical reactor. The performance of the predictive con troller is investigated in the presence of measurement disturbances and parametric uncertainty. It is also shown that statistically inferred input-output models can be a substitute whenever detailed fundamental models are not available. A nonlinear autoregressive polynomial model based on observed plant data is built and incorporated into the control scheme. The catalytic oxidation of ethylene in a periodically-forced, continuous stirred-tank reactor is considered as the test case.
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Title: APPLICATION OF SPECTRUM OBSERVATORY MEASUREMENTS TO SUPPORT TRAFFIC MODEL-BASED DYNAMIC SPECTRUM ACCESS
Creator: Taher, Tanim Mohammed
Date: 2014, 2014-07
Description: In a 2012 report, the President’s Council of Advisors in Science and Technology (PCAST) published a memorandum that calls for the...
Show moreIn a 2012 report, the President’s Council of Advisors in Science and Technology (PCAST) published a memorandum that calls for the identification of 1000 MHz of Federal Spectrum to be shared with private (commercial) users. This dissertation proposes a system that employs RF measurements for spectrum usage modeling and Dynamic Spectrum Access (DSA) methodologies that utilize the modeling information to permit sharing of wireless resources. A procedure called the Comprehensive Band Modeling (CBM) procedure is developed that automatically models measured RF data from any band of interest and identifies the locations of signals and holes present in the band. The output of the CBM procedure is summarized in a compact versatile format that makes DSA applications feasible. The research primarily focuses on the 450-474 MHz land mobile radio (LMR) band, and several additional bands like the TV band and the 2.5-2.7 GHz band. However, the research methodology and techniques are broadly applicable to many more frequency ranges. The research has four main areas: (a) spectrum sensor design and measurements, (b) occupancy modeling, (c) communicating the modeling information in a compact form to secondary users to support DSA algorithms and protocols, and (d) tools and metrics for spectrum sharing favorability analysis. Three spectrum sensor platforms were employed in measurements – (1) a spectrum analyzer based Spectrum Observatory (SO) that was developed earlier, (2) a specially purposed software-defined radio (SDR) for measuring LMR channels, (3) and a high-speed and portable SO system based on a sensor called the RFeye. An SO continually measures RF data in a band at a high temporal resolution such that the channel switching activity is seen – like, transmitters turning on and off. Spectrum measurements of the individual RF channels in the 450-474 MHz LMR band and the two commercial bands are used to generate statistical traffic and occupancy models. Long-term measurement data is used to assess how stationary the channel is, and how often the model parameters need to be updated. The spectrum observatory supports a network of Secondary Users (SU) by communicating the traffic model parameters in a compact format to the SUs. The SUs share Primary User (PU) channels via DSA techniques. The DSA algorithms take advantage of the model parameters provided by the SO to maximize SU throughput with limited interference on the PU. The DSA coexistence techniques are evaluated via simulation. The simulation results including Spectrum Opportunity Accessed (SOA), SU throughput, and collision rates are then analyzed to provide an assessment of DSA-based spectrum sharing in that band. The main contribution of this dissertation is the aforementioned CBM procedure. The white spaces in the frequency and time domains, that is, the underutilized spectrum opportunities available for possible secondary use via DSA are automatically identified, as well as the frequency locations that are not conducive to DSA due to the presence of frequent primary licensee transmissions. In CBM, white spaces are referred to as ‘Holes’, and the licensed primary transmission frequencies as ‘Signals’. Useful information about the duty cycles and traffic patterns of incumbent users’ activity within possible secondary use channels is extracted and modeled. The model enables prospective secondary users of white spaces to predict the expected level of interference in any channel, which allows for channel ranking and optimal selection of DSA transmission parameters. The CBM model is describable by a tiered structure, where the first tier identifies the holes and signals; the second tier ranks the holes in terms of available bandwidth and incumbent duty cycle; and the third tier models the infrequent incumbent transmissions. With the three tiers of information, an SU can readily identify all the suitable DSA channels within the entire spectrum band. This essential summary information is retrieved as a “Hole Descriptor Object” (HDO) that is both compact and tractable. Empirical spectrum measurement data obtained from the three different SO platforms is used to test the performance of the CBM procedure in the 2500-2700 MHz frequency range that currently has WiMAX deployments, the TV white space band, and the 450-474 MHz LMR band in Chicago. Spectrum measurement data runs into hundreds of megabytes or gigabytes. As such, the raw information is not very applicable in practical wireless networks. The HDO objects on the other hand are compact and only kilobytes in size. The HDO objects contain all the useful and applicable information necessary for any smart radio (primary or secondary) to select transmission parameters like frequency of operation and bandwidth, so that it can efficiently operate. Thus, the advantage of the CBM procedure is that it summarizes gigabytes of raw spectrum measurements in a usable compact format that can be directly used by practical smart radios to operate using DSA paradigms. Another advantage of CBM is that it is comprehensive and automatically identifies all holes and signals. The research findings are of interest and value to a variety of Federal and Commercial entities. The models and relevant model parameters for public safety radio in the LMR band have been provided on request to the Public Safety and Homeland Security Bureau of the Federal Communications Commission (FCC). The DSA feasibility analysis methodology is of great national economic interest based on the contents of the PCAST report. The PCAST report recommends finding 1000 MHz of federal frequencies to be allocated for shared commercial and federal use. However, the technology for doing so and identifying the suitable bands requires measurements of actual spectrum usage, modeling the occupancy and existing traffic activity, and assessing DSA feasibility – these are important research aspects, and all of which are addressed in this dissertation. The results are of crucial importance to policy makers like the FCC and NTIA who will ultimately make the spectrum allocations decisions. A future network of commercial DSA SU radios operating in a shared band is likely to need access to a system to obtain live information about PU activity to optimally operate in the band with high throughput and low interference. The overall system, based on the CBM procedure and HDO objects, proposed in this thesis describes a framework for providing this information as a service to DSA networks, and hence the work is also of practical relevance to radio system designers.
Ph.D. in Electrical Engineering, July 2014
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Title: PSYCHOLOGICAL WELL-BEING AND ONLINE MINDFULNESS TRAINING
Creator: Stickney, Laurie
Date: 2013-04-15, 2013-05
Description: Despite the improvements in resources and communication in today’s world, many people still do not have access to mental health resources....
Show moreDespite the improvements in resources and communication in today’s world, many people still do not have access to mental health resources. Mindfulness, a type of meditation, has been shown to be effective at reducing stress, reducing pain, and increasing general mental well-being. Mindfulness has the potential to reach many people though internet-based interventions. However, more research is needed to determine whether mindfulness retains its efficacy when delivered over the internet. Participants engaged in a six week program of internet-based mindfulness interventions. Facets of mental well-being were assessed at various time points including mood state, anxiety, quality of life, mindfulness, and psychological inflexibility. Hierarchical Linear Modeling demonstrated that over time, participants significantly increased their level of mindfulness and decreased in their psychological inflexibility. Measurements pertaining to mood, anxiety, quality of life, and perceived stress did not change significantly. Nonetheless, results from the present study suggest the potential efficacy of internet-based mindfulness interventions and highlight the need for future research in this domain.
M.S. in Psychology, May 2013
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Title: Study of electric rates and ratemaking
Creator: Barrer, Glen A, Shaffer, Sydney
Date: 2009, 1915
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studyofelectricr00barr
Thesis (B.S.)--Armour Institute of Technology, 1915 Bibliography: leaves 43-47 B.S. in...
Show morehttp://www.archive.org/details/studyofelectricr00barr
Thesis (B.S.)--Armour Institute of Technology, 1915 Bibliography: leaves 43-47 B.S. in Electrical Engineering, 1915
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Title: Financial Incubators, India
Creator: Shah, Shruti
Date: 2010-05-01, 2010-05

Title: "NEW HORIZON" - SUSTAINABLE NEW CITY, DAHEJ, GUJARAT, INDIA
Creator: Suthar, Bhumika
Date: 2013, 2013-07
Description: The purpose of this thesis is to develop an ideal environment for developing new cities, that are not just green and clean but also self...
Show moreThe purpose of this thesis is to develop an ideal environment for developing new cities, that are not just green and clean but also self-sustainable. Current cities in world supports great infrastructure and accommodates approximately 6-7 Million people. According to UN, the population growth in next 15 years would be 10-15 million people will be living in the cities and that would increase loads on existing cities infrastructure. To avoid these inevitable circumstances we need new sustainable cities. In last two decades rapid urbanization and industrialization has caused indelible effects on our ecosystem. This thesis will provide in-depth insight on current urban problems and present a solution in form of new sustainable city. A holistic approach has been taken towards developing a new city at Dahej in Gujarat, India, which will be a prototype for new sustainable community development in future. It focuses on creating a perfect balance between environmental, social and economic sustainability. This new city will provide quality of life and environment. This thesis is a sincere approach to provide a strategic solution for post-carbon world and qualitative phenomena of the sustainable low-carbon future.
M.S. in Architecture, July 2013
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Title: Minimum-bias angular and trigger-associated correlations from 200 GeV p-p collisions: jets, flows, centrality, and the underlying event, Proceedings of the XLIII International Symposium on Multiparticle Dynamics
Creator: Prindle, D.
Date: 2013-09-15, 2013-09-15
Publisher: IIT Press
Description: The mechanisms leading to the hadronic final state of high-energy proton-proton collisions remain an unresolved issue at the RHIC and LHC. A...
Show moreThe mechanisms leading to the hadronic final state of high-energy proton-proton collisions remain an unresolved issue at the RHIC and LHC. A substantial contribution to the hadronic final state from minimum-bias (MB) jets is dominated by non-perturbative processes and may provide the common base for any high-energy dijet. Observation of a same-side (on azimuth)“ridge” in LHC p-p collisions suggests to some that hydrodynamic flows may play a role in that small system at higher energies. The issue of p-p centrality vs triggered jets has emerged in the context of gluon trans- verse distributions in the proton inferred from DIS data. Attempts have been made to isolate and study the underlying event (UE) complementary to triggered dijets, and it is suggested that multiple parton interactions may contribute to the UE. Reference [1] considered theoretical and experimental results for UE systematics and p-p centrality in the context of a two-component (soft+hard) model derived from single-particle pt spectrum nch systematics. The study concluded that there may be a substantial contribution to the UE from the triggered dijet and that p-p centrality is not controlled significantly by a jet trigger condition (if p-p centrality is relevant at all). Further study of two-particle correlations in p-p collisions was called for, particularly the nch dependence of MB correlations. We report a comprehensive study of MB (no pt cuts) angular correlations and trigger-associated (TA) yt correlations (transverse rapidity yt = ln[(mt + pt)/mπ]) from 200 GeV p-p collisions. Angular correlations are characterized by 2D model fits that accurately distinguish among proton dissociation structure (soft), jet-related structure (hard) and a nonjet azimuth quadrupole. All angular correlations are simply represented by a (2+1)-component model. The hard and quadrupole component scale simply with the soft-component multiplicity ns, clarifying the role of centrality and the eikonal model in p-p collisions. 2D TA correlations project to a marginal 1D trigger spectrum that can be simply predicted from pt spec- trum nch dependence. 2D TA distributions can then be processed to reveal MB jet fragment (hard component) systematics comparable to measured fragmentation functions. Hard-component azimuth dependence relative to the trigger relates to UE studies. From TA analysis we can establish the kinematic limits of jet fragment production in p-p collisions.
Sponsorship: IIT College of Science, High Energy Physics Division of Argonne National Laboratory
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Title: LASER MICROMACHINING, SINTERING, AND LASER-INDUCED PLASMA DEBURRING
Creator: Gao, Yibo
Date: 2013, 2013-12
Description: Lasers can provide non-mechanical-contact, localized and concentrated energy input to materials with controlled durations and high spatial...
Show moreLasers can provide non-mechanical-contact, localized and concentrated energy input to materials with controlled durations and high spatial resolutions down to a few microns or less. Therefore, lasers have more and more applications in manufacturing and materials processing, such as laser micromachining (which is to create micro-scale features through laser-induced material removal) and laser sintering. Despite the previous research work in the literature, many laser-based manufacturing and materials processing areas still require lots of further research work. Specifically, the following topics will be investigated in the research work in this thesis: nanosecond-pulsed laser ablation of silicon carbide at an infrared wavelength, nanosecond laser-induced plasma deburring, two-step nanosecond laser surface texturing, and the fabrication of carbon nanotube (CNT)-ceramic composites through the laser sintering process.
PH.D in Mechanical and Aerospace Engineering, December 2013
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Title: The Intrepid Penguin Lodge at Shackleton Station: AAA-Brochure
Creator: Tolsky, Benjamin
Date: 2011, 2011-05
Description: This is a design for a new research station in Antarctica that also includes Antarctica's first hotel as part of the station. The emphasis is...
Show moreThis is a design for a new research station in Antarctica that also includes Antarctica's first hotel as part of the station. The emphasis is on a modular design that is easily expandable and reconfigurable in order to meet the needs of future Antarctic research and tourism demands. The end result of the project is a single 16 minute animation to demonstrate life at the station both as a daily routine and a seasonal routine, as well as the logistics of shipping and constructing the station in Antarctica.
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Title: Developing a Collaborative On-line Student Research Forum (sequence unknown), IPRO 321 - Deliverables: IPRO 321 Brochure F09
Creator: Abhay, Anandha, Cornelius, Zachary, Corsus, Tom, De Courten-myers, Maximilian, Eberlin, Adam, Kapaldo, James, Nicholson, Bethany, Sizyuk, Yuriy, Sundberg, Stephen
Date: 2009-12
Description: ResearchWeb is meant to broaden IIT undergraduate participation beyond the existing mechanisms such as fellowships, research and reading...
Show moreResearchWeb is meant to broaden IIT undergraduate participation beyond the existing mechanisms such as fellowships, research and reading courses, and departmental projects. There is also the possibility of broadening this program to other scholarly individuals outside of the IIT undergraduate community. These individuals include IIT graduate students, students from other universities, and promising high school students. ResearchWeb is also meant to improve the transition, and perhaps promote if need be, the transition from undergraduate education to graduate education. This would be fulfilled through practical research experience.
Deliverables for IPRO 321:Developing a Collaborative On-line Student Research Forum for Fall 2009
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Title: COLLABORATIVE CONSUMPTION: PROFITS, CONSUMER BENEFITS, AND ENVIRONMENTAL IMPACTS
Creator: Supangkat, Hendrarto Kurniawan
Date: 2014, 2014-05
Description: With increasingly connected consumers and technological advancement, peer- to-peer sharing is emerging as a consumer-led initiative, which is...
Show moreWith increasingly connected consumers and technological advancement, peer- to-peer sharing is emerging as a consumer-led initiative, which is aimed to exploit slack capacities and lower the cost of consuming private goods. Sharing is praised for its potential bene ts of improving consumer access, consumer surplus, and environmental impact. On the other hand, sharing may possess credible threats to producers because of cannibalization and reduced sales quantity. This thesis is composed of three papers on the subject of peer-to-peer sharing of durable goods, e.g., cars, bikes, gadgets, and household appliances. The rst paper studies pricing and product design decisions of a single-product monopolist in a market. We identify the conditions under which a rm would accom- modate or hinder peer-to-peer sharing by pricing the product appropriately. We nd that the rm's pro t can be enhanced only when the consumer valuation heterogene- ity is neither too high nor too low, and the product's intrinsic value is su ciently high. In addition, contrary to the conventional wisdom, we show that sharing does not always improve consumer access to products. Furthermore, some consumers may end up being worse o . Finally, we nd that social sharing may enhance or impede product innovation, depending on consumer heterogeneity and the size of sharing groups. In the second paper, we study whether social sharing will encourage or discour- age product di erentiation. We nd that the two ways of expanding the market, one consumer-initiated and one rm-initiated, can be strategic complements or substi- tutes, depending on consumer heterogeneity, group size, product intrinsic value, and cost structure. We characterize such conditions. For example, we show that accom- modating sharing provides the rm a higher incentive to introduce a di erentiated product when the product intrinsic value and consumer heterogeneity are both low, x or are both high. We also extend the study by allowing consumers to endogenously choose their sharing group size, and show that it may enhance or worsen the rm's pro t. The third paper focuses on the environmental impact stemming from produc- tion and consumption, in the presence of peer-to-peer sharing. The product usage of sharing consumers is modeled as a function of capacity congestion and group size. We show that a "danger" zone exists where sharing is pro table for the rm but is not friendly to the environment. When the rm has an in uence on the sharing group size (e.g., by promoting sharing programs in metropolitan areas or college towns), the economic incentive and environmental impact can be aligned. Speci cally, we nd that stronger congestion e ects may induce the producer to promote sharing in larger groups, which in turn results in a more positive environmental impact. Such situations are more likely to occur when the product unit cost is large. Moreover, we characterize conditions under which the rm may prefer heterogeneous networks composed of groups with di erent sizes or social networks with lower homophily, and meanwhile the environmental impact can be improved.
PH.D in Management Science, May 2014
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Title: The Intrepid Penguin Lodge at Shackleton Station
Creator: Tolsky, Benjamin
Date: 2011, 2011-05
Description: This is a design for a new research station in Antarctica that also includes Antarctica's first hotel as part of the station. The emphasis is...
Show moreThis is a design for a new research station in Antarctica that also includes Antarctica's first hotel as part of the station. The emphasis is on a modular design that is easily expandable and reconfigurable in order to meet the needs of future Antarctic research and tourism demands. The end result of the project is a single 16 minute animation to demonstrate life at the station both as a daily routine and a seasonal routine, as well as the logistics of shipping and constructing the station in Antarctica.
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Title: NANOPORE STOCHASTIC DETECTION OF ANTHRAX
Creator: Han, Yujing
Date: 2014, 2014-05
Description: Nanopore stochastic sensor using a biological protein ion channel has emerged as a powerful sensing technique due to its outstanding features...
Show moreNanopore stochastic sensor using a biological protein ion channel has emerged as a powerful sensing technique due to its outstanding features such as label- and amplification-free detection, rapidness, high sensivity and selectivity. Development of a nanopore stochastic sensor for the rapid detection of anthrax can effectively prevent and control the spread of disease infection, and become extremely useful in biodefense. Two sensor design strategies were studied: one is chemistry-based detection of dipicolinic acid; and the other is genetics-based detection of anthrax lethal factor. Both approaches used in this study should find useful application in the development of nanopore sensors for the detection of other biomolecules and pathogens.
M.S. in Chemistry, May 2014
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Title: Modeling, monitoring and control strategies for high temperature short time pasteurization systems - 2. Lethality-based control
Creator: Negiz, A., Ramanauskas, P., Cinar, A., Schlesser, J. E., Armstrong, D. J.
Date: 1998-02
Publisher: ELSEVIER SCI LTD
Description: A lethality-based control system was designed to provide accurate control of a high temperature shout time (HTST) pasteurizer and to process...
Show moreA lethality-based control system was designed to provide accurate control of a high temperature shout time (HTST) pasteurizer and to process milk products with a lethality equivalent of 161 degrees F (71.67 degrees C) or above for 15 s. This control system provides significant flexibility in operating the process and optimizing functional properties of the food components. Multivariable control of an HTST pasteurizer is implemented by using product total lethality to determine the controller set-points. The equation that relates the temperature and flow rate combinations to the product total lethality, 161 degrees F (71.67 degrees C), 15 s, was modified to permit overprocessing levels specified by plant personnel. By using this equation and the set-point value selected for the other variable, set-point values for the temperature or the flow rate controller were computed. The flow and temperature controllers are integrated into a real-time monitoring and control system. The monitoring and control system includes the multivariable controller, the lethality rate calculation module, statistical monitoring of the total lethality, product flow rate, hot wafer outlet temperature, and holding tube exit temperature measurements, and the display screens for visual inspection of the monitoring tools. This study attempted to achieve compliance of the HTST process operation with the recommended Pasteurized Milk Ordinance by providing a margin between the alarm limits of the monitoring chart and the safety limits.
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Title: Lakeshore East Community School
Creator: Fernandes, Marie
Date: 2010-07-29

Title: FUNCTIONAL ANALYSIS OF UBIQUITIN-LIKE PROTEIN 4A
Creator: Zhao, Yu
Date: 2015, 2015-12
Description: Ubiquitin-like protein 4A (Ubl4A) was identified as a housekeeping gene at X chromosome. It involves in the guided entry of tail-anchored (GET...
Show moreUbiquitin-like protein 4A (Ubl4A) was identified as a housekeeping gene at X chromosome. It involves in the guided entry of tail-anchored (GET) protein pathway in which tail-anchored (TA) proteins are transported to endoplasmic reticulum (ER). However, Ubl4A also involves other functions not related to GET pathway, such as tumor suppression and DNA damage-mediated apoptosis. Up to date, the function of Ubl4A in mammals is still largely unknown. We found that either overexpression or knockdown of Ubl4A promoted cell death in cell culture system. Using an in vivo genetic knockout system, we found that Ubl4A knockout mice displayed a high neonatal mortality and had a defect in glycogen synthesis, which is mainly controlled by a key protein kinase Akt. Loss of Ubl4A resulted in the impairment of insulin-induced Akt translocation to the plasma membrane, an essential step for Akt activation. We demonstrated that Ubl4A directly interacted with actin-related protein 2/3 (Arp2/3) complex, further accelerated Arp2/3 complex-dependent actin branching, thereby bringing Akt to proximity into the plasma membrane for activation. Furthermore, we showed that Ubl4A-mediated actin branching also played important roles in other cellular activities, such as formations oflamellipodia and filopodia, macrophage phagocytosis, wound healing, and neutrophil chemotaxis. These findings provide us a new insight into understanding the roles of Ubl4A in cellular function and a molecular basis for treatment of related human diseases.
Ph.D. in Biology, December 2015
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