University of Houston

About: University of Houston is a education organization based out in Houston, Texas, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 23074 authors who have published 53903 publications receiving 1641968 citations.

Turbulence suppression in free shear flows by controlled excitation.

Abstract: Turbulence suppression in the near field of a free shear flow under controlled excitation is investigated in four circular jets, a plane jet, and a plane mixing layer The suppression is a consequence of an excitation-induced modification of the shear layer structure and occurs at the excitation frequency corresponding to the maximally unstable disturbance frequency of the initial free shear layer The most pronounced suppression occurs when the shear layer is excited at a frequency 40% higher than the natural roll-up frequency Excitation at a Strouhal number of about 0017 produces a rapid roll-up and early breakdown of the shear layer, and thus inhibits the formation of the energetic large-scale vortices which otherwise survive farther downstream, grow to larger sizes, and undergo successive pairings in the corresponding unexcited flow

Economic Perceptions and Vote Choice: Disentangling the Endogeneity

Abstract: Much previous research shows that variation in vote choice closely follows variation in economic perceptions over time. A number of scholars argue that the pattern is rooted in cross-sectional effects and have found apparent evidence of such effects. However, most of these studies do not take into account the possibility that economic perceptions are themselves structured by vote choice, which poses potentially serious implications. We begin to address this endogeneity, focusing specifically on Lewis-Beck's (1988) analysis of economic voting. The results suggest that the cross-sectional effects of the economy on vote choice have been substantially overstated.

A reversible solid-state crystalline transformation in a metal phosphide induced by redox chemistry.

Abstract: We demonstrate low-potential intercalation of lithium in a solid-state metal phosphide. A topotactic first-order transition between different but related crystal structures at room temperature takes place by an electrochemical redox process: MnP4 ↔ Li7MnP4. The P-P bonds in the MnP4 structure are cleaved at the time of Li insertion (reduction) to produce crystalline Li7MnP4 and are reformed after reoxidation to MnP4, thereby acting as an electron storage reservoir. This is an unusual example of facile covalent bond breaking within the crystalline solid state that can be reversed by the input of electrochemical energy.

Tumor-mediated liver X receptor-[alpha] activation inhibits CC chemokine receptor-7 expression on dendritic cells and dampens antitumor responses

Abstract: Sterol metabolism has recently been linked to innate and adaptive immune responses through liver X receptor (LXR) signaling. Whether products of sterol metabolism interfere with antitumor responses is currently unknown. Dendritic cells (DCs) initiate immune responses, including antitumor activity after their CC chemokine receptor-7 (CCR7)-dependent migration to lymphoid organs. Here we report that human and mouse tumors produce LXR ligands that inhibit CCR7 expression on maturing DCs and, therefore, their migration to lymphoid organs. In agreement with this observation, we detected CD83(+)CCR7(-) DCs within human tumors. Mice injected with tumors expressing the LXR ligand-inactivating enzyme sulfotransferase 2B1b (SULT2B1b) successfully controlled tumor growth by regaining DC migration to tumor-draining lymph nodes and by developing overt inflammation within tumors. The control of tumor growth was also observed in chimeric mice transplanted with bone marrow from mice lacking the gene encoding LXR-alpha (Nr1h3(-/-) mice) Thus, we show a new mechanism of tumor immunoescape involving products of cholesterol metabolism. The manipulation of this pathway could restore antitumor immunity in individuals with cancer.

Who Wants To Deliberate—And Why?

Abstract: Interest in deliberative theories of democracy has grown tremendously among political theorists, political scientists, activists, and even government officials. Many scholars, however, are skeptical that it is a practically viable theory, even on its own terms. They argue (inter alia) that most people dislike politics and that deliberative initiatives would amount to a paternalistic imposition. Using two large national samples investigating people's hypothetical willingness to deliberate and their actual participation in response to a real invitation to deliberate with their member of Congress, we find that (1) willingness to deliberate in the United States is much more widespread than expected, and (2) it is precisely those people less likely to participate in traditional partisan politics who are most interested in deliberative participation. They are attracted to such participation as a partial alternative to “politics as usual.”