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December 2019

November 2019

October 2019

  • We celebrated International Open Access Week, October 21-27, by playing "The Game of Open Access" with library colleagues. Visit http://www.openaccessweek.org to learn about other international open access initiatives around the 2019 theme "Open for Whom? Equity in Open Knowledge"
  • Have you heard about the UA Libraries' Open Access Investment Fund? The fund supports initiatives and projects that advance open access. It also supports institutional memberships with specific publishers; UA authors benefit from discounts on article processing charges.
  • The UA Campus Repository has achieved the milestone of making more than 70,000 items publically available. The 70,000th item added to the repository was Bernice Ackerman's Characteristics of Summer Radar Echoes in Arizona, 1956, from the Institute of Atmospheric Physics Scientific Report series.
  • The UA Faculty Publications collection now contains more than 6,000 articles contributed by faculty and researchers under the UA Open Access Policy passed by the UA Faculty Senate.

 

  • Analysis, Simulation, and Optimization of Stochastic Vesicle Dynamics in Synaptic Transmission

    Zhang, Calvin; Peskin, Charles S.; Univ Arizona, Dept Math (WILEY, 2020-01)
    Synaptic transmission is the mechanism of information transfer from one neuron to another (or from a neuron to a muscle or to an endocrine cell). An important step in this physiological process is the stochastic release of neurotransmitter from vesicles that fuse with the presynaptic membrane and spill their contents into the synaptic cleft. We are concerned here with the formulation, analysis, and simulation of a mathematical model that describes the stochastic docking, undocking, and release of synaptic vesicles and their effect on synaptic signal transmission. The focus of this paper is on the parameter p(0), the probability of release for each docked vesicle when an action potential arrives. We study the influence of this parameter on the statistics of the release process and on the theoretical capability of the model synapse in reconstructing various desired outputs based on the timing and amount of neurotransmitter release. This theoretical capability is assessed by formulating and solving an optimal filtering problem. Methods for parameter identification are proposed and applied to simulated data. (c) 2019 Wiley Periodicals, Inc.
  • Code Obfuscation: Why is This Still a Thing?

    Collberg, Christian; Univ Arizona, Dept Comp Sci (ASSOC COMPUTING MACHINERY, 2018)
    Early developments in code obfuscation were chiefly motivated by the needs of Digital Rights Management (DRM) [7]. Other suggested applications included intellectual property protection of software [4] and code diversification to combat the monoculture problem of operating systems [2]. Code obfuscation is typically employed in security scenarios where an adversary is in complete control over a device and the software it contains and can tamper with it at will. We call such situations the Man-At-The-End (MATE) [3] scenario. MATE scenarios are the best of all worlds for attackers and, consequently, the worst of all worlds for defenders: Not only do attackers have physical access to a device and can reverse engineer and tamper with it at their leisure, they often have unbounded resources (time, computational power, etc.) to do so. Defenders, on the other hand, are often severely constrained in the types of protective techniques available to them and the amount of overhead they can tolerate. In other words, there is an asymmetry between the constraints of attackers and defenders. Moreover, DRM is becoming less prevalent (songs for sale on the Apple iTunes Store are no longer protected by DRM, for example); there are new cryptographically-based obfuscation techniques [1] that promise provably secure obfuscation; secure enclaves [5] are making it into commodity hardware, providing a safe haven for security sensitive code; and recent advances in program analysis [12] and generic de-obfuscation [13] provide algorithms that render current code obfuscation techniques impotent. Thus, one may reasonably ask the question: "Is Code Obfuscation Still a Thing?" Somewhat surprisingly, it appears that the answer is yes. In a recent report, Gartner [14] lists 19 companies active in this space (8 of which were founded since 2010) and there are still (in 2017) many papers published on code obfuscation, code de-obfuscation, anti-tamper protection, reverse engineering, and related technologies. One of the reasons for this resurgence of code obfuscation as a protective technology is that, more and more, we are faced with applications where security-sensitive code needs to run on unsecured endpoints. In this talk we will show MATE attacks that appear in many novel and unlikely scenarios, including smart cars [6], smart meters [9], mobile applications such as Snapchat and smartphone games, Internet of Things applications [8], and ad blockers in web browsers [11]. We will furthermore show novel code obfuscation techniques that increase the workload of attackers [10] and which, at least for a time, purport to restore the symmetry between attackers and defenders.
  • Growing Up: Greenhouse Designs for Urban Spaces

    Adams, James; College of Architecture, Planning and Landscape Architecture; Iuliano, Joey (The University of Arizona., 2019-12)
    With the world heading towards a potential food crisis by the year 2050 we need to start looking at current solutions to future problems. One idea is to create more efficient greenhouses where more food can be grown in a smaller space and closer to population centers. By first understanding a brief history of the origins of greenhouses and their historic uses we can further our understanding of how to push these designs into a better future. By utilizing new construction materials, buildings designs, and growing methods, greenhouses may be able to help stem the need for additional agricultural land and food transport. Many companies are already creating urban farms but there is still room for improvement. This study takes a look at some basic ideas towards furthering this goal.
  • If You're Young and Black...A report of a summer program with black male youth in Tucson, Arizona, with recommendations for program development

    Brown, Charles C.; Bradish, Damaris (College of Agriculture, University of Arizona (Tucson, AZ), 1971-05)
  • Is Youth in Social Turmoil?

    Napier, Clay (College of Agriculture, University of Arizona (Tucson, AZ), 1971-08)

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