University of Texas at Austin

About: University of Texas at Austin is a education organization based out in Austin, Texas, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 94352 authors who have published 206297 publications receiving 9070052 citations. The organization is also known as: UT-Austin & UT Austin.

Pulmonary Passage is a Major Obstacle for Intravenous Stem Cell Delivery: The Pulmonary First-Pass Effect

Abstract: Intravenous (IV) stem cell delivery for regenerative tissue therapy has been increasingly used in both experimental and clinical trials. However, recent data suggest that the majority of administered stem cells are initially trapped in the lungs. We sought to investigate variables that may affect this pulmonary first-pass effect. In anesthetized Sprague-Dawley rats, silicone tubing catheters were placed in the left internal jugular vein and common carotid artery. We investigated four different cell types: mesenchymal stromal cells (MSC), multipotent adult progenitor cells (MAPCs), bone marrow-derived mononuclear cells (BMMC), and neural stem cells (NSC). Cells were co-labeled with Qtracker 655 (for flow cytometry) and Qtracker 800 (for infrared imaging) and infused intravenously with continual arterial sample collection. Samples were analyzed via flow cytometry to detect labeled cells reaching the arterial circulation. Following sampling and exsanguination, heart, lungs, spleen, kidney, and liver were harvested and placed on an infrared imaging system to identify the presence of labeled cells. The majority of MSCs were trapped inside the lungs following intravenous infusion. NSC and MAPC pulmonary passage was 2-fold and BMMC passage was 30-fold increased as compared to MSCs. Inhibition of MSC CD49d significantly increased MSC pulmonary passage. Infusion via two boluses increased pulmonary MSC passage as compared to single bolus administration. Infrared imaging revealed stem cells evenly distributed over all lung fields. Larger stem and progenitor cells are initially trapped inside the lungs following intravenous administration with a therapeutically questionable number of cells reaching the arterial system acutely.

Top executive commitment to the status quo: some tests of its determinants

Abstract: Some top executives are more committed to the status quo—particularly to their organization's current strategy and leadership profile—than are others. Most empirical research on upper echelons treats psychological phenomena as a ‘black box’—the unobserved intervening mechanisms—that causes associations between more observable executive characteristics and organizational outcomes. In contrast, this paper attempts to directly examine the determinants of an important element of an executive's psychological orientation—commitment to the status quo (CSQ). We focus on a select set of variables which have been posited in prior research as determinants of executive CSQ, but which have not been directly tested for such a relationship. Based on a large-scale survey methodology, results suggest that an executive's tenure in an industry is a pronounced determinant of CSQ, and has significantly more impact than organizational tenure. As expected, the firm's current performance was found to be positively related to CSQ; this relationship was stronger in high-discretion than in low-discretion industries. Finally, the project reaffirms a well known human tendency: incumbent CEOs tend to believe that their eventual successors should be just like them.

User Association for Load Balancing in Heterogeneous Cellular Networks

Abstract: For small cell technology to significantly increase the capacity of tower-based cellular networks, mobile users will need to be actively pushed onto the more lightly loaded tiers (corresponding to, e.g., pico and femtocells), even if they offer a lower instantaneous SINR than the macrocell base station (BS). Optimizing a function of the long-term rates for each user requires (in general) a massive utility maximization problem over all the SINRs and BS loads. On the other hand, an actual implementation will likely resort to a simple biasing approach where a BS in tier j is treated as having its SINR multiplied by a factor A_j>=1, which makes it appear more attractive than the heavily-loaded macrocell. This paper bridges the gap between these approaches through several physical relaxations of the network-wide optimal association problem, whose solution is NP hard. We provide a low-complexity distributed algorithm that converges to a near-optimal solution with a theoretical performance guarantee, and we observe that simple per-tier biasing loses surprisingly little, if the bias values A_j are chosen carefully. Numerical results show a large (3.5x) throughput gain for cell-edge users and a 2x rate gain for median users relative to a max received power association.

Information technology and the performance of the customer service process: a resource-based analysis

Abstract: Delivering quality customer service has emerged as a strategic imperative, one that is increasingly tied to a firm's information technology resources and capabilities. This paper presents an empirical study that examines the extent to which IT impacts customer service. More specifically, this study investigates the differential effects of various IT resources and capabilities on the performance of the customer service process across firms that compete in the North American life and health insurance industry. The paper builds on (1) information systems work that suggests that the effects of IT are best documented at the level of processes within a firm, (2) information systems work that suggests that the performance effects of IT are likely to be contingent in nature, and (3) developments in the resource-based view, which describes the kinds of IT resources and capabilities that are likely to enable a process in one firm to outperform the same process in competing firms. The findings suggest that tacit, socially complex, firm-specific resources explain variation in process performance across firms and that IT resources and capabilities without these attributes do not. Of particular interest to IS scholars, it is found that shared knowledge between IT and customer service units-an important driver of how IT is implemented and used in the customer service process-is a key IT capability that affects customer service process performance and moderates the impacts of explicit IT resources such as the generic information technologies used in the process and IT spending, which-consistent with resource-based predictions-were not found to be directly and positively associated with relative process performance. The implications of the findings for research and practice are discussed.