Scalar Top Quark Studies with Various Visible Energies

The precision determination of scalar top quark properties will play an important role at a future International Linear Collider (ILC). Recent and ongoing studies are discussed for different experimental topologies in the detector. First results are presented for small mass differences between the scalar top and neutralino masses. This corresponds to a small expected visible energy in the detector. An ILC will be a unique accelerator to explore this scenario. In addition to finding the existence of light stop quarks, the precise measurement of their properties is crucial for testing their impact on the dark matter relic abundance and the mechanism of electroweak baryogenesis. Significant sensitivity for mass differences down to 5 GeV are obtained. The simulation is based on a fast and realistic detector simulation. A vertex detector concept of the Linear Collider Flavor Identification (LCFI)collaboration, which studies pixel detectors for heavy quark flavour identification, is implemented in the simulations for c-quark tagging. The study extends simulations for large mass differences (large visible energy) for which aspects of different detector simulations, the vertex detector design, and different methods for the determination of the scalar top mass are discussed. Based on the detailed simulations we study the uncertainties for the dark matter density predictions and their estimated uncertainties from various sources. In the region of parameters where stop-neutralino co-annihilation leads to a value of the relic density consistent with experimental results, as precisely determined by the Wilkinson Microwave Anisotropy Probe (WMAP), the stop-neutralino mass difference is small and the ILC will be able to explore this region efficiently.Comment: 11 pages, 11 figures, presented at SUSY'0

EFFECTS OF VARIED MUSIC TEMPOS AND VOLUMES ON VERTICAL IMPACT FORCES PRODUCED IN STEP AEROBICS

INTRODUCTION This study examined the effects of selected combinations of music tempos and volumes used during a step aerobics routine on the peak ground reaction forces (GRF') exerted on a force plate while stepping METHODS 'helve college females having beginning step aerobics experience performed a 20 min. Basic step routine on a .15 m bench. The subjects performed a step aerobics routine to cadences of 122 and 130 bpm and the music volume was varied from 68 to 83 dB while landing on a Kistler piezoelectric force plate connected to an Ariel APAS. The GRFs were sampled at 500 Hz for three 20 sec intervals during 5 min application of each tempo1 decibel condition. The middle 3 impacts of the right and left strides within each 20 sec interval were analyzed, resulting in a total of 9 right and 9 left footfall GRFs. RESULTS The subjects' mean age was 22.8 2.8 years, height was 164.9 4.9 cm, and weight was 60.8 6.4 kg. The peak vertical GRFs were analyzed using a 2 x 2x 2Ax9 ANOVA (Volume x Tempo x Ft x Trial) with repeated measures on all factors. No significant effects were found for factors of volume (p = .424), stride (p = .217), or trial (p = .733). Significant differences for the varied tempo factor were found to exist at the .09 level when the tempo of the music was increased from 122 to 130 bpm. The mean peak vertical impact GRFs were 908.2 149.6 Nt (167% BWT), 930.8 147.3Nt(171%BWT), 921.5 167.0Nt(170%BWT),and943.3 187.1 Nt(174%BWT)forthe treatment conditions of 68 dB1122 bpm, 83 dB1122 bpm, 68 dB1130 bpm, and 83 dbl130 bpm, respectively. CONCLUSIONS The findings suggest that the faster loading and unloading rates of the musculature due to the faster tempo caused less control of the movement and this resulted in a 4% increase in the vertical GRFs. Therefore, the use of faster tempos in a beginning level step aerobics class could be a source for elevated risk for potential injury. REFERENCES Finch A., & Hecko, K. (1996). Effects of prolonged bench stepping on impact forces. Biomechanics in Sports MV ISBS in Sports, Madeira Portugal, 248-25 1. Newton, R., & Humphries, B. (1991). Peak ground reaction forces during step aerobics, walking, and jogging. Proceedings of Ninth ISBS Symposium. Ames, Iowa, 67-71

Investigating people: a qualitative analysis of the search behaviours of open-source intelligence analysts

The Internet and the World Wide Web have become integral parts of the lives of many modern individuals, enabling almost instantaneous communication, sharing and broadcasting of thoughts, feelings and opinions. Much of this information is publicly facing, and as such, it can be utilised in a multitude of online investigations, ranging from employee vetting and credit checking to counter-terrorism and fraud prevention/detection. However, the search needs and behaviours of these investigators are not well documented in the literature. In order to address this gap, an in-depth qualitative study was carried out in cooperation with a leading investigation company. The research contribution is an initial identification of Open-Source Intelligence investigator search behaviours, the procedures and practices that they undertake, along with an overview of the difficulties and challenges that they encounter as part of their domain. This lays the foundation for future research in to the varied domain of Open-Source Intelligence gathering

Effects of seawater pCO2 and temperature on calcification and productivity in the coral genus Porites spp. : an exploration of potential interaction mechanisms

This work was supported by the UK Natural Environment Research Council (Award NE/I022973/1) to AAF and NA.Understanding how rising seawater pCO2 and temperatures impact coral aragonite accretion is essential for predicting the future of reef ecosystems. Here we report 2 long term (10-11 month) studies assessing the effects of temperature (25 and 28°C) and both high and low seawater pCO2 (180-750 μatm) on the calcification, photosynthesis and respiration of individual massive Porites spp. genotypes. Calcification rates were highly variable between genotypes but high seawater pCO2 reduced calcification significantly in 4 of 7 genotypes cultured at 25°C but in only 1 of 4 genotypes cultured at 28°C. Increasing seawater temperature enhanced calcification in almost all corals but the magnitude of this effect was seawater pCO2 dependent. The 3°C temperature increase enhanced calcification rate on average by 3% at 180 μatm, by 35% at 260 μatm and by >300% at 750 μatm. The rate increase at high seawater pCO2 exceeds that observed in inorganic aragonites. Responses of gross/net photosynthesis and respiration to temperature and seawater pCO2 varied between genotypes but rates of all these processes were reduced at the higher seawater temperature. Increases in seawater temperature, below the thermal stress threshold, may mitigate against ocean acidification in this coral genus but this moderation is not mediated by an increase in net photosynthesis. The response of coral calcification to temperature cannot be explained by symbiont productivity or by thermodynamic and kinetic influences on aragonite formation.Publisher PDFPeer reviewe