Evaluation of a high-torque backlash-free roller actuator

The results are presented of a test program that evaluated the stiffness, accuracy, torque ripple, frictional losses, and torque holding capability of a 16:1 ratio, 430 N-m (320 ft-lb) planetary roller drive for a potential space vehicle actuator application. The drive's planet roller supporting structure and bearings were found to be the largest contributors to overall drive compliance, accounting for more than half of the total. In comparison, the traction roller contacts themselves contributed only 9 percent of the drive's compliance based on an experimentally verified stiffness model. The drive exhibited no backlash although 8 arc sec of hysteresis deflection were recorded due to microcreep within the contact under torque load. Because of these load-dependent displacements, some form of feedback control would be required for arc second positioning applications. Torque ripple tests showed the drive to be extremely smooth, actually providing some damping of input torsional oscillations. The drive also demonstrated the ability to hold static torque with drifts of 7 arc sec or less over a 24 hr period at 35 percent of full load

Knowledge of Clinical Measures and Healthcare Adherence In Young Gay and Bisexual Men Living with HIV/AIDS

Knowledge of HIV/AIDS test results and adherence to healthcare interventions are two important outcomes that reflect proper HIV/AIDS management. This study aimed to determine which demographic and HIV acceptance measures were significantly associated with health literacy and adherence indicators in young MSM. 200 HIV/AIDS positive young MSM completed computer based surveys regarding demographics, HIV/AIDS health literacy indicators, and HIV/AIDS acceptance measures. It was found that young African American MSM, in comparison to young white MSM, had lower odds of knowing both viral load and CD4 measures; health literacy indicators. Further, participants who had a high school diploma were found to have increased odds of knowing both their CD4 and viral load measures in comparison to those young MSM participants who had not obtained a high school diploma. Further research should examine the factors associated with the lack of health literacy reported by young African American MSM

A Study of Juvenile Waiver

In a footnote to its recent decision, In re Dennis M, the California Supreme Court recommended, that juvenile officers and police be prepared to give their compulsory Miranda warning in terms that reflect the language and experience of today’s juveniles. This language stimulated our attempt to draft and test the efficacy of a simplified Miranda warning, potentially more understandable to juveniles, and consistent with juvenile law requirements. The purpose of this article is to relate the findings of an empirical study which sought to answer two questions: 1) should the Miranda warning be revised for the juvenile offender; and 2) does a minor have the capacity knowingly and intelligently to waive his Miranda rights

echinus, required for interommatidial cell sorting and cell death in the Drosophila pupal retina, encodes a protein with homology to ubiquitin-specific proteases

Background: Programmed cell death is used to remove excess cells between ommatidia in the Drosophila pupal retina. This death is required to establish the crystalline, hexagonal packing of ommatidia that characterizes the adult fly eye. In previously described echinus mutants, interommatidial cell sorting, which precedes cell death, occurred relatively normally. Interommatidial cell death was partially suppressed, resulting in adult eyes that contained excess pigment cells, and in which ommatidia were mildly disordered. These results have suggested that echinus functions in the pupal retina primarily to promote interommatidial cell death. Results: We generated a number of new echinus alleles, some of which are likely null mutants. Analysis of these alleles provides evidence that echinus has roles in cell sorting as well as cell death. echinus encodes a protein with homology to ubiquitin-specific proteases, which cleave ubiquitin-conjugated proteins at the ubiquitin C-terminus. The echinus locus encodes multiple splice forms, including two proteins that lack residues thought to be critical for deubiquitination activity. Surprisingly, ubiquitous expression in the eye of versions of Echinus that lack residues critical for ubiquitin specific protease activity, as well as a version predicted to be functional, rescue the echinus loss-of-function phenotype. Finally, genetic interactions were not detected between echinus loss and gain-of-function and a number of known apoptotic regulators. These include Notch, EGFR, the caspases Dronc, Drice, Dcp-1, Dream, the caspase activators, Rpr, Hid, and Grim, the caspase inhibitor DIAP1, and Lozenge or Klumpfuss. Conclusions: The echinus locus encodes multiple splice forms of a protein with homology to ubiquitin-specific proteases, but protease activity is unlikely to be required for echinus function, at least when echinus is overexpressed. Characterization of likely echinus null alleles and genetic interactions suggests that echinus acts at a novel point(s) to regulate interommatidial cell sorting and/or cell death in the fly eye

Strategy and Choice in the 1988 Presidential Primaries

In recent years, thinking about the American Presidential primaries has been dominated by the image of Carter's victory in 1976. Conventional wisdom in the eighties has advised Presidential candidates to focus on the early contests in Iowa and New Hampshire, and to at least match, or better yet, exceed the expectations that the press, pollsters, and pundits have for them in those states. The successful campaign, it was thought, had to force the competition out by the end of March in order to lock up the nomination before the convention. This common wisdom - the so-called "momentum theory" - will now have to be revised as a result of what happened in the 1988 primaries. While one candidate from each patty did eventually emerge victorious in 1988, no one followed the Carter script as closely as expected. The Democratic race was not clearly resolved until Dukakis managed consecutive victories over Jackson in Wisconsin (April 5), New York (April 19) and Pennsylvania (April 26). On the Republican side, even though the race was over after Super Tuesday, the conventional "momentum" story was still marred by the odd-and in the end, meaningless-­outcome in Iowa Republican caucuses. Bush exceeded expectations in Iowa, but in a negative direction, and both Dole and Robertson were unable to convert their successes into any advantage in New Hampshire and the South. In this paper, we use data from a series of 12 exit polls conducted by the Los Angeles Times to explain the course of the 1988 Democratic and Republican presidential primary campaigns. The Los Angeles Times sample of primaries includes the critical early Democratic and Republican contests in Iowa and New Hampshire, six Super Tuesday states, and the Democratic primaries in Illinois, New York, Pennsylvania and California. The story we tell is quite simple. Momentum in both races was slowed by regionalism, and in the Democratic contest specifically, by the non-strategic support that blacks and affluent liberal whites gave Jesse Jackson. Momentum accelerated in the New York and Pennsylvania primaries as moderate and Jewish voters strategically switched to Dukakis in order to block Jesse Jackson's nomination. Both Bush and Dukakis staked out positions for themselves near the center of the ideological spectrum in their respective parties. As it turned out, the distribution of voter preferences, combined with strategic complications typical of multicandidate races, served to make the middle an advantageous spot for the victorious candidates

Cell death and transcriptional responses induced in larvae of the nematode Haemonchus contortus by toxins/toxicants with broad phylogenetic efficacy

Establishing methods to investigate treatments that induce cell death in parasitic nematodes will promote experimental approaches to elucidate mechanisms and to identify prospective anthelmintics capable of inducing this outcome. Here, we extended recent progress on a method to monitor cell death and to identify small molecule inhibitors i

Salvinorin B Meth­oxy­methyl Ether

The title compound [MOM-SalB; systematic name: methyl (2S,4aR,6aR,7R,9S,10aS,10bR)-2-(3-fur­yl)-9-meth­oxy­meth­oxy-6a,10b-dimethyl-4,10-dioxo-2,4a,5,6,7,8,9,10a-octa­hydro-1H-benzo[f]isochromene-7-carboxyl­ate], $C_{23}H_{30}O_8$, is a deriv­ative of the κ-opioid salvinorin A with enhanced potency, selectivity, and duration of action. Superimposition of their crystal structures reveals, surprisingly, that the terminal C and O atoms of the MOM group overlap with the corresponding atoms in salvinorin A, which are separated by an additional bond. This counter-intuitive isosterism is possible because the MOM ether adopts the 'classic anomeric' conformation (gauche–gauche), tracing a helix around the planar acetate of salvinorin A. This overlap is not seen in the recently reported structure of the tetra­hydro­pyranyl ether, which is less potent. The classic anomeric conformation is strongly favoured in alk­oxy­methyl ethers, but not in substituted acetals, which may contribute to their reduced potency. This structure may prove useful in evaluating models of the activated $\kappa$-opioid receptor

Coronary Evaluation Using Multi-detector Spiral Computed Tomography Angiography: Statistical Design and Analysis

Contrast-enhanced multi-detector row spiral computed tomography (MDCT) has been introduced as a method for non-invasive visualization of coronary artery stenosis. To determine the diagnostic accuracy of MDCT coronary angiography, as compared to the “gold standard” invasive coronary angiography, sensitivity and specificity are estimated (95% Confidence Intervals). Three separate levels of estimation are computed: at the patient level, at the coronary artery level, and at the coronary artery segment level. We review the methodology for the estimation of sensitivity and specificity of non-clustered binary data (patient level analysis) and present a methodology for the estimation of sensitivity and specificity that considers the patient as a cluster and the coronary arteries (or coronary artery segments) as the diagnostic units of the study (DUOS) within each cluster. We also present how to estimate the weighted kappa for the comparison of ordinal measures of stenosis when non-clustered and clustered data are considered and the mean difference for the comparison of continuous measures of stenosis when non-clustered and clustered data are considered. Finally, we present a methods for determining the statistical precision of estimates sensitivity and specificity, weighted kappa and mean difference when clustered data are considered