University of Nebraska Omaha

About: University of Nebraska Omaha is a education organization based out in Omaha, Nebraska, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 4526 authors who have published 8905 publications receiving 213914 citations. The organization is also known as: UNO & University of Omaha.

Avatars, People, and Virtual Worlds: Foundations for Research in Metaverses *

Abstract: Metaverses are immersive three-dimensional virtual worlds in which people interact as avatars with each other and with software agents, using the metaphor of the real world but without its physical limitations. The ubiquitous availability of high speed Internet access has spurred enormous interest in virtual worlds like Second Life and World of Warcraft, both in terms of user gaming and as a new technological platform for global virtual collaboration. These environments have potential for richer, more engaging collaboration, but their capabilities have yet to be examined in depth. Of particular interest in this paper is the use of metaverses for virtual team collaboration. We develop a conceptual model for research in metaverses that is based on five key constructs: (1) the metaverse itself, (2) people/avatars, (3) metaverse technology capabilities, (4) behaviors, and (5) outcomes. We present an indepth characterization of metaverse technology capabilities from a socio-technical view that recognizes the potential for variation in emergent interaction and in outcomes. Example propositions and a discussion of key issues and challenges show how the model can be used to further research and practice in virtual teams in the context of these new environments.

Endocrine-disrupting effects of cattle feedlot effluent on an aquatic sentinel species, the fathead minnow.

Abstract: Over the last decade, research has examined the endocrine-disrupting action of various environmental pollutants, including hormones, pharmaceuticals, and surfactants, in sewage treatment plant effluent. Responding to the growth of concentrated animal feeding operations (CAFOs) and the pollutants present in their wastewater (e.g., nutrients, pharmaceuticals, and hormones), the U.S. Environmental Protection Agency developed a new rule that tightens the regulation of CAFOs. In this study, we collected wild fathead minnows (Pimephales promelas) exposed to feedlot effluent (FLE) and observed significant alterations in their reproductive biology. Male fish were demasculinized (having lower testicular testosterone synthesis, altered head morphometrics, and smaller testis size). Defeminization of females, as evidenced by a decreased estrogen:androgen ratio of in vitro steroid hormone synthesis, was also documented. We did not observe characteristics in either male or female fish indicative of exposure to environmental estrogens. Using cells transfected with the human androgen receptor, we detected potent androgenic responses from the FLE. Taken together, our morphologic, endocrinologic, and in vitro gene activation assay data suggest two hypotheses: a) there are potent androgenic substance(s) in the FLE, and/or b) there is a complex mixture of androgenic and estrogenic substances that alter the hypothalamic-pituitary-gonadal axis, inhibiting the release of gonadotropin-releasing hormone or gonadotropins. This is the first study demonstrating that the endocrine and reproductive systems of wild fish can be adversely affected by FLE. Future studies are needed to further investigate the effects of agricultural runoff and to identify the biologically active agents, whether natural or pharmaceutical in origin.

Hepatocyte Transplantation for the Treatment of Human Disease

Abstract: A great deal of work with animal models indicates that hepatocytes transplanted into the liver or spleen survive, function, and participate in the normal regenerative process. Recent clinical studies suggest that hepatocyte transplantation may be useful for bridging patients to whole organ transplantation and for providing metabolic support during liver failure and for replacing whole organ transplantation in certain metabolic liver diseases. In specific situations where the rate of death of host hepatocytes is high, the transplanted cells can repopulate the native liver. Techniques have been established for the large scale isolation, culture and cryopreservation of human hepatocytes. Shortage of donor organs and the need for immunosuppression are two major hurdles to widespread application of this procedure, and current research in experimental animals is aimed at addressing these problems.

Enhanced valley splitting in monolayer WSe2 due to magnetic exchange field

Abstract: Exploiting the valley degree of freedom to store and manipulate information provides a novel paradigm for future electronics. A monolayer transition-metal dichalcogenide (TMDC) with a broken inversion symmetry possesses two degenerate yet inequivalent valleys, which offers unique opportunities for valley control through the helicity of light. Lifting the valley degeneracy by Zeeman splitting has been demonstrated recently, which may enable valley control by a magnetic field. However, the realized valley splitting is modest (∼0.2 meV T-1). Here we show greatly enhanced valley spitting in monolayer WSe2, utilizing the interfacial magnetic exchange field (MEF) from a ferromagnetic EuS substrate. A valley splitting of 2.5 meV is demonstrated at 1 T by magnetoreflectance measurements and corresponds to an effective exchange field of ∼12 T. Moreover, the splitting follows the magnetization of EuS, a hallmark of the MEF. Utilizing the MEF of a magnetic insulator can induce magnetic order and valley and spin polarization in TMDCs, which may enable valleytronic and quantum-computing applications.