Unmanned seismometer levels self, corrects drift errors

Four-component, three-axis, feedback-controlled seismograph incorporates electronic circuitry for leveling and for monitoring the feedback signal required for servo-centering. Viscous damping of the earth-motion signal, compensation of the residual long-term drift, and centering of the seismometers are provided by automatic mechanisms

What may be learnt about the archaeology of islands from archaeologically derived models of the exploration of Polynesia, 1966-2001?

Polynesian archaeology is one regional specialization in the world-wide practice of archaeological investigations of islands, oceans and seas. It is timely to consider how Polynesian archaeology fits within that newly-articulated framework of theoretical and methodological advances concerned with islands. To do this, I examine the history of archaeologically-derived models of the exploration of Polynesia developed since the invention of radiocarbon dating

On optical imaging through aircraft turbulent boundary layers

Optical resolution quality as affected by aircraft turbulent boundary layers is analyzed. Wind-tunnel data was analyzed to obtained the variation of boundary layer turbulence scale length and mass density rms fluctuations with Mach number. The data gave good agreement with a mass density fluctuation turbulence spectrum that is either isotropic of orthogonally anisotropic. The data did not match an isotropic turbulence velocity spectrum which causes an anisotropic non-orthogonal mass density fluctuation spectrum. The results indicate that the average mass density rms fluctuation is about 10% of the maximum mass density across the boundary layer and that the transverse turbulence scale size is about 10% of the boundary layer thickness. The results indicate that the effect of the turbulent boundary layer is large angle scattering which decreases contrast but not resolution. Using extinction as a criteria the range of acceptable aircraft operating conditions are given

Intercellular production of Hydrogen peroxide in Solanum lycopersicum: an immune response to Salmonella infection

Produce associated gastroenteritis in recent years has become more associated with fruits and vegetables rather than raw meat and dairy, with thousands of deaths per year recorded. Outbreaks of Salmonella have been reported from a multitude of vegetables such as lettuce, spinach and tomatoes. Many of these outbreaks are the result of infection via non-typhoid Salmonella species such as Salmonella enterica sv. Typhimurium. The ecology of Salmonella as a human pathogen via vegetable hosts is increasingly being studied, however much is still unknown. Studies have shown that Salmonella may proliferate in both the rhizosphere and phyllosphere of the tomato plant Solanum lycopersiscum. In tomatoes, Salmonella has varying levels of proliferation success depending on the variety of tomato in question. Previous studies had shown that tomatoes of the cherry variety were significantly more resistant to Salmonella proliferation than larger varieties. S. lycopersicum var. cerasiforme and var. alicante were inoculated with Salmonella enterica (LT2) sv. Typhimurium and allowed to incubate for 72 hours. Following this, tomatoes were homogenised and samples plated on XLD. This study found that Salmonella ability to proliferate in var. cerasiforme was significantly different (α=0.05) when compared to var. alicante. With Salmonella proliferating up to a 1 log more in var. alicante than in var. cerasiforme. This study suggested that this difference was due to an innate difference in immune response efficacy between var. cerasiforme and var. alicante. Studies regarding plant immune responses have shown that production of hydrogen peroxide is a common response to microbial attack. Using a novel methodology, this study extracted the intercellular fluid from the tomato fruit in both var. alicante and var. cerasiforme. Analysis via fluorometric quantification found that var. cerasiforme contained significantly higher amounts of hydrogen peroxide in its intercellular fluid than var. alicante. These data suggest that the inherent and increased resistance to Salmonella proliferation in var. cerasiforme compared to var. alicante is at least in part due to its increased levels of hydrogen peroxide in its intercellular fluid

The case of Heinrich Wilhelm Poll (1877-1939): A German-Jewish geneticist, eugenicist, twin researcher, and victim of the Nazis

This paper uses a reconstruction of the life and career of Heinrich Poll as a window into developments and professional relationships in the biological sciences in Germany in the period from the beginning of the twentieth century to the Nazi seizure of power in 1933. Poll's intellectual work involved an early transition from morphometric physical anthropology to comparative evolutionary studies, and also found expression in twin research - a field in which he was an acknowledged early pioneer. His advocacy of eugenics led to participation in state-sponsored committees convened to advise on social policy, one of which debated sterilisation and made recommendations that led eventually to the establishment of the notorious Kaiser Wilhelm Institute for Anthropology, Human Heredity and Eugenics. However, his status as a prominent geneticist and, in particular, as a eugenicist had an ironic and ultimately tragic dimension. Heinrich Poll was of Jewish birth, and this resulted in his career being destroyed by an application of the population policies he had helped put in place

New records for Tephritidae (Diptera) in Great Smoky Mountains National Park

As part of the All Taxon Biological Inventory (ATBI) being conducted in the Great Smoky Mountains National Park (GSMNP), we report new distribution and host plant records for nine Tephritidae species

Defrauding the Public Interest: A Critical Examination of Reengineered Audit Processes and the Likelihood of Detecting Fraud

In the past few years, most of the major international public accounting firms have reengineered their audit processes to improve the cost effectiveness of completing an audit and to focus on value-added services for clients. The reengineered audit processes generally focus on a client’s business processes and the information systems used by the client to generate financial information. In essence, the new audit approaches deemphasize direct testing of the underlying transactions and account balances. Such an approach emphasizes analytical procedures as the main source of substantive evidence. During this same time period, however, the profession (through the AICPA) explicitly acknowledged the profession’s responsibility for fraud detection. The main premise of this paper is that the increased emphasis on systems assessments is at odds with the profession’s position regarding fraud detection because most material frauds originate at the top levels of the organization, where controls and systems are least prevalent and effective. As such, the profession may be paying lip service to fraud detection, while at the same time changing the audit process in a manner that is less effective at detecting the most common frauds

Trace element abundance determinations by Synchrotron X Ray Fluorescence (SXRF) on returned comet nucleus mineral grains

Trace element analyses were performed on bulk cosmic dust particles by Proton Induced X Ray Emission (PIXE) and Synchrotron X Ray Fluorescence (SXRF). When present at or near chondritic abundances the trace elements K, Ti, Cr, Mn, Cu, Zn, Ga, Ge, Se, and Br are presently detectable by SXRF in particles of 20 micron diameter. Improvements to the SXRF analysis facility at the National Synchrotron Light Source presently underway should increase the range of detectable elements and permit the analysis of smaller samples. In addition the Advanced Photon Source will be commissioned at Argonne National Laboratory in 1995. This 7 to 8 GeV positron storage ring, specifically designed for high-energy undulator and wiggler insertion devices, will be an ideal source for an x ray microprobe with one micron spatial resolution and better than 100 ppb elemental sensitivity for most elements. Thus trace element analysis of individual micron-sized grains should be possible by the time of the comet nucleus sample return mission

The MSFC space station/space operations mechanism test bed

The Space Station/Space Operations Mechanism Test Bed consists of the following: a hydraulically driven, computer controlled Six Degree-of-Freedom Motion System (6DOF); a six degree-of-freedom force and moment sensor; remote driving stations with computer generated or live TV graphics; and a parallel digital processor that performs calculations to support the real time simulation. The function of the Mechanism Test Bed is to test docking and berthing mechanisms for Space Station Freedom and other orbiting space vehicles in a real time, hardware-in-the-loop simulation environment. Typically, the docking and berthing mechanisms are composed of two mating components, one for each vehicle. In the facility, one component is attached to the motion system, while the other component is mounted to the force/moment sensor fixed in the support structure above the 6DOF. The six components of the contact forces/moments acting on the test article and its mating component are measured by the force/moment sensor

Plants for predators - a participatory experiment

Encouraging natural enemies by growing attractant plants is a highly effective method of pest control in organic systems. However, it is important to establish which plants are most effective at attracting benefi cial insects. Experiments were carried out by 179 HDRA members, who grew four plant species (Coriander, Corn Marigold, Fennel and Phacelia) in their gardens and allotments. Over the course of the growing season, assessments were made on the growth and flowering of the plants and the presence of four key groups of beneficial insect (ladybirds, hoverflies, lacewings and parasitic wasps). Phacelia established quickly and its long flowering period meant it attracted insects throughout the summer. However, Phacelia was only the most attractive plant at the end of the season and insects preferred the other trial plants when they were in flower. Results highlight the importance of growing a range of flowering plants to provide resources for beneficials throughout their activity period