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Creators/Authors contains: "Gallagher, Kevin"

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  1. People Search Websites, a category of data brokers, collect, catalog, monetize and often publicly display individuals' personally identifiable information (PII). We present a study of user privacy rights in 20 such websites assessing the usability of data access and data removal mechanisms. We combine insights from these two processes to determine connections between sites, such as shared access mechanisms or removal effects. We find that data access requests are mostly unsuccessful. Instead, sites cite a variety of legal exceptions or misinterpret the nature of the requests. By purchasing reports, we find that only one set of connected sites provided access to the same report they sell to customers. We leverage a multiple step removal process to investigate removal effects between suspected connected sites. In general, data removal is more streamlined than data access, but not very transparent; questions about the scope of removal and reappearance of information remain. Confirming and expanding the connections observed in prior phases, we find that four main groups are behind 14 of the sites studied, indicating the need to further catalog these connections to simplify removal. 
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  2. Ecosystem destruction and biodiversity loss are now widespread, extremely rapid, and among the top global anthropogenic risks both in terms of likelihood and overall impact. Thorough impact evaluation of these environmental abuses—essential for conservation and future project planning—requires good analysis of local ecological and environmental data in addition to social and economic impacts. We characterized the deforestation and biodiversity impacts of energy investments in Southeast Asia using multiple geospatial data sources related to forest cover and loss data from 2000 to 2018, other landcover data, and the location, type, and characteristics of energy investments. This study paid particular attention to different types of power plants and financing sources. We identified critical buffer zones and forest structures impacted by these projects in accordance with IUCN criteria and spatial ecology. The paper introduces a novel, replicable analytical framework that goes beyond earlier studies in which all forests are treated as equivalent. It characterizes forests based on spatial morphological structures such as core forest, edges, islands, and bridges, allowing for a more nuanced understanding of deforestation and its impacts on biodiversity. Preliminary findings suggest that projects financed by Chinese development banks pose different risks compared to non-Chinese financing. The study also reveals significant differences in biodiversity impacts based on the type of energy source, be it coal or hydro. The study offers critical insights into the trade-offs between energy development and biodiversity conservation. It provides actionable metrics and strategies for policymakers, conservationists, and development banks to prioritize forest and habitat preservation in Southeast Asia and globally. 
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  3. Deepfakes have become a dual-use technology with applications in the domains of art, science, and industry. However, the technology can also be leveraged maliciously in areas such as disinformation, identity fraud, and harassment. In response to the technology's dangerous potential many deepfake creation communities have been deplatformed, including the technology's originating community – r/deepfakes. Opening in February 2018, just eight days after the removal of r/deepfakes, MrDeepFakes (MDF) went online as a privately owned platform to fulfill the role of community hub, and has since grown into the largest dedicated deepfake creation and discussion platform currently online. This position of community hub is balanced against the site's other main purpose, which is the hosting of deepfake pornography depicting public figures- produced without consent. In this paper we explore the two largest deepfake communities that have existed via a mixed methods approach utilizing quantitative and qualitative analysis. We seek to identify how these platforms were and are used by their members, what opinions these deepfakers hold about the technology and how it is seen by society at large, and identify how deepfakes-as-disinformation is viewed by the community. We find that there is a large emphasis on technical discussion on these platforms, intermixed with potentially malicious content. Additionally, we find the deplatforming of deepfake communities early in the technology's life has significantly impacted trust regarding alternative community platforms. 
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  4. People Search Websites aggregate and publicize users’ Personal Identifiable Information (PII), previously sourced from data brokers. This paper presents a qualitative study of the perceptions and experiences of 18 participants who sought information removal by hiring a removal service or requesting removal from the sites. The users we interviewed were highly motivated and had sophisticated risk perceptions. We found that they encountered obstacles during the removal process, resulting in a high cost of removal, whether they requested it themselves or hired a service. Participants perceived that the successful monetization of users PII motivates data aggregators to make the removal more difficult. Overall, self management of privacy by attempting to keep information off the internet is difficult and its’ success is hard to evaluate. We provide recommendations to users, third parties, removal services and researchers aiming to improve the removal process. 
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  5. Pattern formation of biological structures involves the arrangement of different types of cells in an ordered spatial configuration. In this study, we investigate the mechanism of patterning the Drosophila eye epithelium into a precise triangular grid of photoreceptor clusters called ommatidia. Previous studies had led to a long-standing biochemical model whereby a reaction-diffusion process is templated by recently formed ommatidia to propagate a molecular prepattern across the eye. Here, we find that the templating mechanism is instead, mechanochemical in origin; newly born columns of differentiating ommatidia serve as a template to spatially pattern flows that move epithelial cells into position to form each new column of ommatidia. Cell flow is generated by a source and sink, corresponding to narrow zones of cell dilation and contraction respectively, that straddle the growing wavefront of ommatidia. The newly formed lattice grid of ommatidia cells are immobile, deflecting, and focusing the flow of other cells. Thus, the self-organization of a regular pattern of cell fates in an epithelium is mechanically driven. 
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  6. Phytochromes are red-light photoreceptors that were first characterized in plants, with homologs in photosynthetic and non-photosynthetic bacteria known as bacteriophytochromes (BphPs). Upon absorption of light, BphPs interconvert between two states denoted Pr and Pfr with distinct absorption spectra in the red and far-red. They have recently been engineered as enzymatic photoswitches for fluorescent-marker applications in non-invasive tissue imaging of mammals. This article presents cryo- and room-temperature crystal structures of the unusual phytochrome from the non-photosynthetic myxobacteriumStigmatella aurantiaca(SaBphP1) and reveals its role in the fruiting-body formation of this photomorphogenic bacterium. SaBphP1 lacks a conserved histidine (His) in the chromophore-binding domain that stabilizes the Pr state in the classical BphPs. Instead it contains a threonine (Thr), a feature that is restricted to several myxobacterial phytochromes and is not evolutionarily understood. SaBphP1 structures of the chromophore binding domain (CBD) and the complete photosensory core module (PCM) in wild-type and Thr-to-His mutant forms reveal details of the molecular mechanism of the Pr/Pfr transition associated with the physiological response of this myxobacterium to red light. Specifically, key structural differences in the CBD and PCM between the wild-type and the Thr-to-His mutant involve essential chromophore contacts with proximal amino acids, and point to how the photosignal is transduced through the rest of the protein, impacting the essential enzymatic activity in the photomorphogenic response of this myxobacterium. 
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