JPEG steganography with particle swarm optimization accelerated by AVX

Digital steganography aims at hiding secret messages in digital data transmitted over insecure channels. The JPEG format is prevalent in digital communication, and images are often used as cover objects in digital steganography. Optimization methods can improve the properties of images with embedded secret but introduce additional computational complexity to their processing. AVX instructions available in modern CPUs are, in this work, used to accelerate data parallel operations that are part of image steganography with advanced optimizations.Web of Science328art. no. e544

Leaders\u27 Accounts: A Study of Transnational NGOs Leadership Views on Accountability

The increased involvement of non-state actors such as nongovernmental organizations (NGOs) in The increased involvement of non-state actors such as nongovernmental organizations (NGOs) in shaping various national and global policy processes raises serious questions about the accountability, authority, and legitimacy of these important yet unelected actors. Although there is no consensus on how to define accountability, broadly the concept refers to the idea that some hold others responsible for their actions according to a set of standards defining proper behavior. However, deciding to whom and to what standards NGOs are accountable and how they are (or should be) held accountable remain central and open questions in accountability debates. This study relies on both qualitative and quantitative methods, introducing the use of qualitative pattern analysis to understand not only what leaders of TNGOs have to say about accountability, but also how they describe their accountability experiences. It uses the TNGO initiative datasets, which include in-depth interview data for 152 CEOs of U.S.- registered TNGOs, as well as secondary data collected for each of the organizations in the sample. Drawing from the nonprofit, management, and international relations scholarship, I explore the three central questions of accountability debates: What is accountability? Accountable to whom? And how? I argue that once one addresses each of these accountability questions, taking an actor-centered perspective, it is possible to understand how accountability practices vary across transnational NGOs. I propose the concept of accountability dissonance to explain the disconnect between the three main questions of accountability. Through the empirical chapters, I show that TNGO leaders expressed often complex views about their accountability experiences, yet they generally struggled to communicate their practices. I stress the need to pay attention to the substantive meaning of accountability messaging and to the connections among definitions, audiences, and responses. The phenomenon of accountability dissonance persists because leaders express their accountability using tools and processes that are mismatched to their definitions and audiences. Furthermore, the data suggest that the types of organizations TNGO leaders manage matter in very different ways, contingent on the aspect of accountability being considered. To reach a holistic understanding, I propose an overarching framework using the analogy of the puzzle to highlight the need for a more integrated approach to TNGO accountability, one hinging on the ability to target the communication of accountability performance to specific audiences

The site-2 protease

AbstractThe site-2 protease (S2P) is an unusually-hydrophobic integral membrane protease. It cleaves its substrates, which are membrane-bound transcription factors, within membrane-spanning helices. Although structural information for S2P from animals is lacking, the available data suggest that cleavage may occur at or within the lipid bilayer. In mammalian cells, S2P is essential owing to its activation of the sterol regulatory element binding proteins (SREBPs); in the absence of exogenous lipid, cells lacking S2P cannot survive. S2P is also important in the endoplasmic reticulum (ER) stress response, activating several different membrane-bound transcription factors. Human patients harboring reduction-of-function mutations in S2P exhibit an array of pathologies ranging from skin defects to neurological abnormalities. Surprisingly, Drosophila melanogaster lacking S2P are viable and fertile. This article is part of a Special Issue entitled: Intramembrane Proteases

Adaptation to ER Stress Is Mediated by Differential Stabilities of Pro-Survival and Pro-Apoptotic mRNAs and Proteins

The accumulation of unfolded proteins in the endoplasmic reticulum (ER) activates a signaling cascade known as the unfolded protein response (UPR). Although activation of the UPR is well described, there is little sense of how the response, which initiates both apoptotic and adaptive pathways, can selectively allow for adaptation. Here we describe the reconstitution of an adaptive ER stress response in a cell culture system. Monitoring the activation and maintenance of representative UPR gene expression pathways that facilitate either adaptation or apoptosis, we demonstrate that mild ER stress activates all UPR sensors. However, survival is favored during mild stress as a consequence of the intrinsic instabilities of mRNAs and proteins that promote apoptosis compared to those that facilitate protein folding and adaptation. As a consequence, the expression of apoptotic proteins is short-lived as cells adapt to stress. We provide evidence that the selective persistence of ER chaperone expression is also applicable to at least one instance of genetic ER stress. This work provides new insight into how a stress response pathway can be structured to allow cells to avert death as they adapt. It underscores the contribution of posttranscriptional and posttranslational mechanisms in influencing this outcome