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In multicellular organisms, cell type diversity and fate depend on specific sets of transcript isoforms generated by post-transcriptional RNA processing. Here, we used Schmidtea mediterranea, a flatworm with extraordinary regenerative abilities and a large pool of adult stem cells, as an in vivo model to study the role of Uridyl-rich small nuclear RNAs (UsnRNAs), which participate in multiple RNA processing reactions including splicing, in stem cell regulation. We characterized the planarian UsnRNA repertoire, identified stem cell-enriched variants and obtained strong evidence for an increased rate of UsnRNA 3’-processing in stem cells compared to their differentiated counterparts. Consistently, components of the Integrator complex showed stem cell-enriched expression and their depletion by RNAi disrupted UsnRNA processing resulting in global changes of splicing patterns and reduced processing of histone mRNAs. Interestingly, loss of Integrator complex function disrupted both stem cell maintenance and regeneration of tissues. Our data show that the function of the Integrator complex in UsnRNA 3’-processing is conserved in planarians and essential for maintaining their stem cell pool. We propose that cell type-specific modulation of UsnRNA composition and maturation contributes to in vivo cell fate choices, such as stem cell selfrenewal in planarians.

The book, Blown to Bits, uncovers the many ways that the new digital world has changed and is changing our whole environment. Some changes are incremental but others are more revolutionary. Some of the changes that we welcome are slowly eroding our privacy and are changing the rules of ownership. This book illuminates the complexities of these changes. I have attempted to capture the central points in selected chapters, and in some cases I have added new material or new examples to replace dated material. I picked chapters to summarize that address the following topics (and more). There are many pieces of data that exist about each of us that aggregators can piece together often because we willingly give it up to receive some service. Because of that we have little privacy left. Ownership of digitized content is being redefined legally because digital copies are as good as the original and because those copies are difficult to control. The change from an analog world to a digital world is revolutionary, and the social customs and laws are slow to adapt to the change. Encryption now is generally accepted by legislators because it is necessary for banking transactions and other commercial activity, but it gives rise to activities such as the dark web (example, the Silk Road). How does the technology behind the dark web work? The pervasive nature of digital images, digital text, GPS data, metadata, and the nature of software applications makes inadvertent disclosure of information almost impossible to control. How can laws be fashioned to control predatory behavior on the web? The supplementary materials I have created unpacks the chapters that focus on these issues. In addition I have added other materials useful for instructors who choose to use the book (some technical material, assignments and rubrics).

Dinosaur material was collected from the upper Brushy Basin Member of the Morrison Formation (Jurassic) on Little Cedar Mountain in east-central Utah. The specimens came from a portion of the Brushy Basin that consists of a brittle mudstone and durable fine-grained sandstone inter-bedded with a nodular marl. Both elastic layers contained bones, which suggests that they were first deposited in sands then buried by mud of a fluvial system. Elements found include a fragmented sauropod and theropod tooth, a sauropod scapula, coracoid, femur, tibia, fibula, caudal vertebrae, ribs, pubis, and phalanx. The fragmented theropod tooth is from a large carnosaur believed to be an allosaur. No signs of scavenging or predation have yet been found. It is believed that these large theropods were constantly shedding teeth at each feeding. The sauropod tooth is from a camarasaur. This tooth is believed to have come from younger strata and was eroded down slope. Comparative studies of bone morphology show that the post-cranial elements closely resemble those of the genus Apatosaurus. The scapula, coracoid, fibula, femur, and caudal vertebrae are the most complete. Therefore, the taxonomic assignment was determined from these elements, primarily the caudal vertebrae. Several of the elements show signs of weathering. The coracoid and scapula show significant weathering on the side that was first exposed during excavation. This side was probably exposed to the air longer than the underside, which shows less damage due to weathering. It is quite possible that these bones were exposed for several years. Also, many bones show signs of flaking, which is another indicator that they were exposed for some time after deposition. Bone orientation and type suggest that the post-cranial elements represent one individual. Most of the bones were disarticulated with the exception of the five caudal vertebrae. The presence of asymmetric ripple marks in the sandstone, from which the sauropod bones were

The main theme running through these three chapters is that economic agents are often forced to respond to events that are not a direct result of their actions or other agents actions. The optimal response to these shocks will necessarily depend on agents' understanding of how these shocks arise. The economic environment in the first two chapters is analogous to the classic chain store game. In this setting, the addition of unintended trembles by the agents creates an environment better suited to reputation building. The third chapter considers the competitive equilibrium price dynamics in an overlapping generations environment when there are supply and demand shocks. The first chapter is a game theoretic investigation of a reputation building game. A sequential equilibrium model, called the "error prone agents" model, is developed. In this model, agents believe that all actions are potentially subjected to an error process. Inclusion of this belief into the equilibrium calculation provides for a richer class of reputation building possibilities than when perfect implementation is assumed. In the second chapter, maximum likelihood estimation is employed to test the consistency of this new model and other models with data from experiments run by other researchers that served as the basis for prominent papers in this field. The alternate models considered are essentially modifications to the standard sequential equilibrium. While some models perform quite well in that the nature of the modification seems to explain deviations from the sequential equilibrium quite well, the degree to which these modifications must be applied shows no consistency across different experimental designs. The third chapter is a study of price dynamics in an overlapping generations model. It establishes the existence of a unique perfect-foresight competitive equilibrium price path in a pure exchange economy with a finite time horizon when there are arbitrarily many