Evolution of recollection and prediction in neural networks

Abstract — A large number of neural network models are based on a feedforward topology (perceptrons, backpropagation networks, radial basis functions, support vector machines, etc.), thus lacking dynamics. In such networks, the order of input presentation is meaningless (i.e., it does not affect the behavior) since the behavior is largely reactive. That is, such neural networks can only operate in the present, having no access to the past or the future. However, biological neural networks are mostly constructed with a recurrent topology, and recurrent (artificial) neural network models are able to exhibit rich temporal dynamics, thus time becomes an essential factor in their operation. In this paper, we will investigate the emergence of recollection and prediction in evolving neural networks. First, we will show how reactive, feedforward networks can evolve a memory-like function (recollection) through utilizing external markers dropped and detected in the environment. Second, we will investigate how recurrent networks with more predictable internal state trajectory can emerge as an eventual winner in evolutionary struggle when competing networks with less predictable trajectory show the same level of behavioral performance. We expect our results to help us better understand the evolutionary origin of recollection and prediction in neuronal networks, and better appreciate the role of time in brain function. I

Offer Strategy Model of Integrative Negotiation for Automated Negotiation Agent: Multiple Equivalent Simultaneous Offers and Argumentation-based Negotiation

Automated negotiation has attracted increasing interest and received phenomenal attention in the area of electronic market (e-market). Most of the studies on the automated negotiation focused on the distributive (zero-sum) negotiation, and their effectiveness is only illustrated in a single-issue negotiation between software agent-to-software agent interaction. In this study, we propose an offer strategy model of integrative negotiation for an automated negotiation agent and focus on software agent-to-human interaction. Our offer strategy model is based on the integrative approach and negotiation theory, which emphasize the importance of exchanging information among negotiators and multi-issue negotiation including package offers helping to achieve an integrative (win-win) outcome. In developing this model, we are incorporating negotiation strategy of argumentation-based negotiation and negotiation tactic of multiple equivalent simultaneous offers as an offer strategy to achieve an integrative (win-win) negotiation outcome. We expect that the result from applying the offer strategy model becomes more attractive and persuasive, thus may increase negotiation outcome satisfaction for both economic measure and social-psychological measure

Multiscale Exploration of Mouse Brain Microstructures Using the Knife-Edge Scanning Microscope Brain Atlas

Connectomics is the study of the full connection matrix of the brain. Recent advances in high-throughput, high-resolution 3D microscopy methods have enabled the imaging of whole small animal brains at a sub-micrometer resolution, potentially opening the road to full-blown connectomics research. One of the first such instruments to achieve whole-brain-scale imaging at sub-micrometer resolution is the Knife-Edge Scanning Microscope (KESM). KESM whole-brain data sets now include Golgi (neuronal circuits), Nissl (soma distribution), and India ink (vascular networks). KESM data can contribute greatly to connectomics research, since they fill the gap between lower resolution, large volume imaging methods (such as diffusion MRI) and higher resolution, small volume methods (e.g., serial sectioning electron microscopy). Furthermore, KESM data are by their nature multiscale, ranging from the subcellular to the whole organ scale. Due to this, visualization alone is a huge challenge, before we even start worrying about quantitative connectivity analysis. To solve this issue, we developed a web-based neuroinformatics framework for efficient visualization and analysis of the multiscale KESM data sets. In this paper, we will first provide an overview of KESM, then discuss in detail the KESM data sets and the web-based neuroinformatics framework, which is called the KESM brain atlas (KESMBA). Finally, we will discuss the relevance of the KESMBA to connectomics research, and identify challenges and future directions

BubR1 acetylation at prometaphase is required for modulating APC/C activity and timing of mitosis

Regulation of BubR1 is central to the control of APC/C activity. We have found that BubR1 forms a complex with PCAF and is acetylated at lysine 250. Using mass spectrometry and acetylated BubR1-specific antibodies, we have confirmed that BubR1 acetylation occurs at prometaphase. Importantly, BubR1 acetylation was required for checkpoint function, through the inhibition of ubiquitin-dependent BubR1 degradation. BubR1 degradation began before the onset of anaphase. It was noted that the pre-anaphase degradation was regulated by BubR1 acetylation. Degradation of an acetylation-mimetic form, BubR1–K250Q, was inhibited and chromosome segregation in cells expressing BubR1–K250Q was markedly delayed. By contrast, the acetylation-deficient mutant, BubR1–K250R, was unstable, and mitosis was accelerated in BubR1–K250R-expressing cells. Furthermore, we found that APC/C–Cdc20 was responsible for BubR1 degradation during mitosis. On the basis of our collective results, we propose that the acetylation status of BubR1 is a molecular switch that converts BubR1 from an inhibitor to a substrate of the APC/C complex, thus providing an efficient way to modulate APC/C activity and mitotic timing

A Case of Recurrent Schneiderian Papilloma of the Lacrimal Sac Invading the Nasal Cavity

A 44-year-old man presented with a history of chronic epiphora, discharge from the right eye, and a palpable mass in the medial canthal area. Irrigation of the lacrimal system revealed bloody discharge. Orbital magnetic resonance imaging (MRI) showed a well-defined heterogeneous enhanced mass filling the lacrimal sac and upper nasolacrimal duct (NLD). A wide excision and surgical biopsy were performed. Histopathology showed the tumor to be an exophytic Schneiderian papilloma with moderate to severe dysplasia. Three months later, the mass was found to be invading the nasal cavity through the NLD. Endoscopic histopathological evaluation confirmed that it was identical to the originally identified papilloma