Development of single crystal beta-alumina membrane

Feasibility of crystal growth technique for beta alumina membrane from molybdenum, tungsten, and iridiu

CSI sensing and control: Analytical and experimental results

Recent work on structural identification and large-angle maneuvers with vibration suppression was presented. The recent work has sought to balance structural and controls analysis activities by involving the analysts directly in the validation and experimental aspects of the research. Some new sensing, actuation, system identification, and control concepts were successfully implemented. An overview of these results is given

Constructing deal networks : brokers as network 'architects' in the U.S. IPO market and other examples.

We introduce the concept of the network architect to extend theory explaining how brokers create and manage structural holes in mediated markets. We argue that a broker's social resources and dependence on the market, along with exogenous deal conditions, influence the broker's motivations and willingness to make tradeoffs between long-term and short-term considerations when constructing deal networks. We develop our model and propositions in the context of the U.S. initial public offerings market and then generalize these arguments to other market contexts

Clinical surveillance of thrombotic microangiopathies in Scotland, 2003-2005

The prevalence, incidence and outcomes of haemolytic uraemic syndrome (HUS) and thrombotic thrombocytopaenic purpura (TTP) are not well established in adults or children from prospective studies. We sought to identify both outcomes and current management strategies using prospective, national surveillance of HUS and TTP, from 2003 to 2005 inclusive. We also investigated the links between these disorders and factors implicated in the aetiology of HUS and TTP including infections, chemotherapy, and immunosuppression. Most cases of HUS were caused by verocytotoxin-producing Escherichia coli (VTEC), of which serotype O157 predominated, although other serotypes were identified. The list of predisposing factors for TTP was more varied although use of immunosuppressive agents and severe sepsis, were the most frequent precipitants. The study demonstrates that while differentiating between HUS and TTP is sometimes difficult, in most cases the two syndromes have quite different predisposing factors and clinical parameters, enabling clinical and epidemiological profiling for these disorders

A search in the COS-B data base for correlated time variability in regions containing objects of interest

As is well known, association of the gamma-ray sources with celestial objects is, in general, difficult on a pure positional basis, while correlated time variability could obviously provide such proof. This technique can be employed on regions of the gamma-ray sky containing interesting objects of known variability at some wavelength even in the absence of a recognized gamma-ray excess with the aim to extract a weak but predictable signal from the surrounding noise. This technique is applied here on a longer variability time scale, generally of the order of days. Photons coming from the sky regions centered on the various celestial objects considered were selected with energies 100 MeV and with arrival directions within an energy-dependent area of radius of approx 6 deg at 100 MeV. In order to construct a time profile of such photons, their arrival times were grouped in bins of dimensions defined by the available photons number and by the value of the period searched for

Finite Element Analysis of Multipass Effects of Vehicles on Soil Compaction

Finite element procedure was used to simulate multiple wheel loading and to predict its effect on soil compaction. Results of nonlinear analysis, conducted using an incremental loading procedure, show effects of tire size, soil type, and number of passes on soil compaction. The results of the study also demonstrate the potential use of the procedure in compaction related studies. However, experimental verification of the model is necessary before the procedure can be recommended for wider use

Graviton n-point functions for UV-complete theories in Anti-de Sitter space

We calculate graviton n-point functions in an anti-de Sitter black brane background for effective gravity theories whose linearized equations of motion have at most two time derivatives. We compare the n-point functions in Einstein gravity to those in theories whose leading correction is quadratic in the Riemann tensor. The comparison is made for any number of gravitons and for all physical graviton modes in a kinematic region for which the leading correction can significantly modify the Einstein result. We find that the n-point functions of Einstein gravity depend on at most a single angle, whereas those of the corrected theories may depend on two angles. For the four-point functions, Einstein gravity exhibits linear dependence on the Mandelstam variable s versus a quadratic dependence on s for the corrected theory.Comment: 29 page

The burden of celebrity: The impact of CEO certification contests on CEO pay and performance

We used the results from Financial World's widely publicized certification contest, CEO of the Year, to investigate the impact of such contests on firm performance and executive compensation. A certification contest ranks actors on performance criteria that key stakeholders accept as credible and legitimate. We found that certified CEOs received higher compensation than noncertified CEOs when performance was high but lower remuneration when performance was poor. Although certifications generate positive abnormal returns when they are first announced, the longer-term impact of CEO certifications appears to be negative

The PAMP c-di-AMP Is Essential for Listeria monocytogenes Growth in Rich but Not Minimal Media due to a Toxic Increase in (p)ppGpp

SummaryCyclic di-adenosine monophosphate (c-di-AMP) is a widely distributed second messenger that appears to be essential in multiple bacterial species, including the Gram-positive facultative intracellular pathogen Listeria monocytogenes. In this study, the only L. monocytogenes diadenylate cyclase gene, dacA, was deleted using a Cre-lox system activated during infection of cultured macrophages. All ΔdacA strains recovered from infected cells harbored one or more suppressor mutations that allowed growth in the absence of c-di-AMP. Suppressor mutations in the synthase domain of the bi-functional (p)ppGpp synthase/hydrolase led to reduced (p)ppGpp levels. A genetic assay confirmed that dacA was essential in wild-type but not strains lacking all three (p)ppGpp synthases. Further genetic analysis suggested that c-di-AMP was essential because accumulated (p)ppGpp altered GTP concentrations, thereby inactivating the pleiotropic transcriptional regulator CodY. We propose that c-di-AMP is conditionally essential for metabolic changes that occur in growth in rich medium and host cells but not minimal medium