Communications Biophysics

COntains reports on six research projects.National Institutes of Health (Grant 2 P01 MH-04737-06)National Institutes of Health (Grant 5 ROl NB-05462-02)Joint Services Electronics Programs (U. S. Army, U. S. Navy, and U. S. Air Force) under Contract DA 36-039-AMC-03200(E)National Science Foundation (Grant GK-835)National Aeronautics and Space Administration (Grant NsG-496

The role of grassland sward islets in the distribution of arthropods in cattle pastures

1. It is well documented that cattle reduce their grazing activity in the vicinity of cattle dung, which gives rise to distinct patches, or islets as they have been termed, of longer sward. The influence of such islets on pasture utilisation and agronomic performance has been widely studied, but very little information is available concerning their influence on grassland biodiversity. 2. In this study the abundance and distribution of arthropods in relation to islets was assessed, using suction sampling, at 26 commercial farms and in a replicated pasture management experiment in the south and east of Ireland. 3. Islets were found to cover approximately 24% of pastures and to contain between 40% and 50% of arthropod individuals. 4. Islets consistently contained a higher density of arthropods, even when the difference in mean sward height between islets and more strongly grazed sward was accounted for. The relative concentration of arthropods in islets declined with increasing mean sward height, which may be related to the recovery of well-grazed non-islet sward. Islets appear to act as refugia from sward removal. 5. The potential importance of islets in maintaining arthropod biodiversity within intensively grazed pastures and the wider grass-based farming landscape is discussed, particularly with reference to standard agronomic practices such as sward topping and chain harrowing, which aim to remove the sward heterogeneity created by grazing livestock

PADME (Phobos and Deimos and Mars Environment): A Proposed NASA Discovery Mission to Investigate the Two Moons of Mars

PADME is a proposed NASA Discovery mission to investigate the origin of two remarkable and enigmatic small bodies, Phobos and Deimos, the two moons of Mars

Graduate attributes in higher education: Examining academics' perception in the Middle East

Higher education institutes are facing increasing pressure to ensure that graduates are equipped with the right set of attributes that will make them desirable to potential employers. To deal with this pressure, universities have for some time been embedding employability attributes into their curriculum through classroom-based teaching and external programs. Yet, little research exists into examining academics' perception of graduate attributes and the potential challenges they face in delivering these attributes. The authors examine graduate attributes that are perceived as most important by academics. The findings suggest that communication, teamwork, problem solving, creativity, critical thinking, time management, and research skills were all seen as important for the employability.This publication was made possible by NPRP grant # [7-1534-5-231] from the Qatar National Research Fund (a member of Qatar Foundation). The findings achieved herein are solely the responsibility of the author[s].Scopu

Economic evaluation of Interactive Audio Media for securing Internet services

Abstract. Internet Telephony (Voice over Internet Protocol or VoIP) has recently become increasingly popular mainly due to its cost advantages and range of advance services. On the same time, SPam over Internet Telephony (SPIT) referred as unsolicited bulk calls sent via VoIP networks by botnets, is expected to become a serious threat in the near future. Audio CAPTCHA (Completely Automated Public Turing test to tell Computers and Human Apart) mechanism were introduced and employed as a security measure to distinguish automated software agents from human beings. The scope of this paper is to present the security economics frame and to have an in-depth review of the related economic models of SPAM and its analogies with SPIT.

Arcus: The X-Ray Grating Spectrometer Explorer

Arcus will be proposed to the NASA Explorer program as a free-flying satellite mission that will enable high-resolution soft X-ray spectroscopy (8-50 Angstroms) with unprecedented sensitivity-effective areas of greater than 500 sq cm and spectral resolution greater than 2500. The Arcus key science goals are (1) to determine how baryons cycle in and out of galaxies by measuring the effects of structure formation imprinted upon the hot gas that is predicted to lie in extended halos around galaxies, groups, and clusters, (2) to determine how black holes influence their surroundings by tracing the propagation of out-flowing mass, energy and momentum from the vicinity of the black hole out to large scales and (3) to understand how accretion forms and evolves stars and circumstellar disks by observing hot infalling and outflowing gas in these systems. Arcus relies upon grazing incidence silicon pore X-ray optics with the same 12m focal length (achieved using an extendable optical bench) that will be used for the ESA Athena mission. The focused X-rays from these optics will then be diffracted by high-efficiency off-plane reflection gratings that have already been demonstrated on sub-orbital rocked flights, imaging the results with flight-proven CCD detectors and electronics. The power and telemetry requirements on the spacecraft are modest. The majority of mission operations will not be complex, as most observations will be long (~100 ksec), uninterrupted, and pre-planned, although there will be limited capabilities to observe targets of opportunity, such as tidal disruption events or supernovae with a 3-5 day turnaround. After the end of prime science, we plan to allow guest observations to maximize the science return of Arcus to the community