Study of porous wall low density wind tunnel diffusers

Porous wall wind tunnel diffusers used with low density hypersonic nozzl

Title Page, Table of Contents, & From the Editor

This semester’s edition of the Psi Sigma Siren showcases the hard work of several graduate students from the UNLV History program, and I believe their tireless dedication to the historian’s craft is reflected by their articles and book reviews. We received numerous submissions, and I am proud of the projects that were accepted for this issue

Infiltration and short-term movement of nitrogen in a silt-loam soil typical of rice cultivation in Arkansas

Rice production in Arkansas is one of the top three crop commodities in terms of cash receipts. Researchers and farmers report that nitrogen (N) needs to be managed according to a variety of factors with two important ones being soil and fertilizer type. The objectives of this experiment were to determine: 1) the degree to which floodwater-incorporated N applied as urea or as ammonium sulfate infiltrates intact cores (7.2-cm dia., 10-cm depth) containing DeWitt siltloam soil, and 2) the distribution of N during 12 h of ponding. Inorganic-N concentrations were analyzed at 2-cm depth intervals in cores following removal of the flood. Nitrogen from applied fertilizer was recovered as ammonium. Ammonium sulfate-N remained in the top 4 cm of soil with concentrations of 375 µg N g-1 in the surface 2 cm and 300 µg N g-1 at the 2 - 4 cm depth after 12 hr of ponding. At all depth intervals below 4 cm, ammonium sulfate-N remained below 30 µg N g-1. In contrast, after 12 h of ponding, N in soil receiving urea was 105 µg N g-1 in the top 2 cm and 173 µg N g-1 at 2-4 cm. At 4-6, 6-8, and 8-10 cm, N was 109, 108, and 35 µg N g-1, respectively, after 12 h of ponding. These results demonstrate immediate and deeper movement of ammonium into silt loam soil receiving urea as compared to ammonium sulfate, demonstrating how the form of N in fertilizer affects its movement into the soil profile

Effects of injury and nutrition on sediment reworking by Clymenella torquata (Annelida: Polychaeta)

Marine infaunas influence sediment chemistry, nutrient cycling, and microbial communities as they burrow, feed, defecate, and irrigate their tubes and burrows. Nonlethal tissue loss to predators or other disturbances is frequently observed in macrofaunal communities, and previous research has reported significant effects of onetime injury on animal activity. In this study, we examined the effects of injury and nutrient enrichment on sediment reworking rates of a common deposit-feeding polychaete, Clymenella torquata. Individual worms in cores were monitored in a recirculating seawater system, and their defecation and sediment mixing monitored under several experimental conditions. Worms held in control (unenriched) sediment or in homogeneously diatom-enriched sediment were injured on days 0 and 7 in a 21 d experiment. Worms held in control sediment or sediment with high surface diatom enrichment were observed in a 7 d experiment following repeated injury. Posterior segments were ablated for the injury treatments, and injury and nutrient supply treatments were crossed in all experiments. Repeated injury significantly decreased surface activities and defecation, and injured worms transported significantly less surface sediment to depth than intact worms. Microalgal enrichment at the sediment surface correlated with an increase in bioturbation; intact worms in surfaceenriched sediments were more active and more likely to hoe surface sediments to depth as evidenced by vertical profiles. These findings help explain how infaunal activities are modified by injury and food availability and can be used to improve models of bioturbation to further elucidate complex benthic community dynamics

A Rac1-independent role for P-Rex1 in melanoblasts

No abstract available

Criminal law as a security project

This paper asks how criminal might be understood as a security project. Following Valverde’s lead, it does this not by trying to define the concept of security, but by looking at the operation of the temporal and spatial logics of the criminal law. It looks first at the basic logics of time and space in conceptions of criminal liability and jurisdiction, before reviewing some recent developments which challenge these practices and what these might mean for criminal law as a security project

An Antibody to De-N-Acetyl Sialic Acid Containing-Polysialic Acid Identifies an Intracellular Antigen and Induces Apoptosis in Human Cancer Cell Lines

Polysialic acid (PSA), an α2,8-linked homopolymer of N-acetylneuraminic acid (Neu5Ac), is developmentally regulated and its expression is thought to be restricted to a few tissues in adults. Recently, we showed that two human pathogens expressed a derivative of PSA containing de-N-acetyl sialic acid residues (NeuPSA). Here we show that an epitope identified by the anti-NeuPSA monoclonal antibody, SEAM 3 (SEAM 3-reactive antigen or S3RA), is expressed in human melanomas, and also intracellularly in a human melanoma cell line (SK-MEL-28), a human T cell leukemia cell line (Jurkat), and two neuroblastoma cell lines (CHP-134 and SH-SY5Y). SEAM 3 binding induced apoptosis in the four cell lines tested. The unusual intracellular distribution of S3RA was similar to that described for the PSA polysialyltransferases, STX and PST, which are also expressed in the four cell lines used here. Interestingly, suppression of PST mRNA expression by transfection of SK-MEL-28 cells with PST-specific short interfering RNA (siRNA) resulted in decreased SEAM 3 binding. The results suggest further studies of the utility of antibodies such as SEAM 3 as therapeutic agents for certain malignancies

(S)-(−)-1-Phenyl­ethanaminium 4-(4,4-di­fluoro-1,3,5,7-tetra­methyl-3a,4a-diaza-4-borata-s-indacen-8-yl)benzoate

The title compound, C8H12N+·C20H18BF2N2O2 −, crystallizes with a significant amount of void space [4.0 (5)%] in the unit cell. The structure displays N—H⋯O hydrogen bonding between the components. The plane formed by the benzoic acid moiety of the BODIPY-CO2 − is twisted by 80.71 (6)° relative to the plane formed by the ring C and N atoms of the tetramethyldipyrrin portion of the molecule