The role of ras gene in the development of haemic neoplasia in Mytilus trossulus

Disseminated neoplasia has been reported in mussels (Mytilus spp) from numerous locations worldwide. This condition is progressive and fatal and the aetiology is unknown. In vertebrates, oncogenes such as ras, and tumour suppressor genes such as p53, play important roles in carcinogenesis. We have cloned a Mytilus trossulus homologue of the vertebrate ras gene, which shows conserved sequence in regions of functional importance. Neoplastic hemolymph samples derived from M. trossulus have been investigated for the presence of ras gene mutations and changes in expression

An Airborne Parachute Compartment Test Bed for the Orion Parachute Test Program

The test program developing parachutes for the Orion/MPCV includes drop tests with parachutes deployed from an Orion-like parachute compartment at a wide range of dynamic pressures. Aircraft and altitude constraints precluded the use of an Orion boilerplate capsule for several test points. Therefore, a dart-shaped test vehicle with a hi-fidelity mock-up of the Orion parachute compartment has been developed. The available aircraft options imposed constraints on the test vehicle development and concept of operations. Delivery of this test vehicle to the desired velocity, altitude, and orientation required for the test is a di cult problem involving multiple engineering disciplines. This paper describes the development of the test technique. The engineering challenges include extraction from an aircraft, reposition of the extraction parachute, and mid-air separation of two vehicles, neither of which has an active attitude control system. The desired separation behavior is achieved by precisely controlling the release point using on-board monitoring of the motion. The design of the test vehicle is also described. The trajectory simulations and other analyses used to develop this technique and predict the behavior of the test vehicle are reviewed in detail. The application of the technique on several successful drop tests is summarized

Comparing Forward and Backward Chaining In Teaching Olympic Weightlifting

The popularity of Olympic‐style weightlifting in fitness routines is growing, but participating in these exercises with improper technique places lifters at increased risk for injury. Fitness training professionals have developed multiple teaching strategies, but have not subjected these strategies to systematic evaluation, particularly with novice lifters. Two strategies recommended by professional training organizations are akin to forward and backward chaining, which have been shown effective at teaching other novel, complex behaviors. The present study compared these forward‐ and backward‐chaining‐like strategies to teach novice lifters “the clean” and “the snatch,” two Olympic weightlifting movements frequently incorporated into high‐intensity training programs. Participants performed lifts taught with forward chaining more accurately than lifts taught with backward chaining

Approaches to Assessing Nutrient Coupling in Open Ocean Datasets

Nutrient coupling describes a process where the biogeochemical cycles of two elements are linked by being incorporated similarly into biomass. This paper uses data from the GEOTRACES GP16 cruise (Eastern Pacific Zonal Transect) to investigate the relationship between certain macronutrients generally coupled to trace elements in terms of their oceanic distributions with the notable exception of in an oxygen minimum zone: cadmium-phosphate and zinc-silicate. There are many methods applied to oceanographic data to correlate analyte concentrations; while they are often presented independently in literature, here we attempt to use them in conjunction for a more thorough interpretation. By compiling 1) depth profiles, 2) differences between the concentrations after applying a scale factor, and 3) direct comparisons of the analytes, greater insight into the correlations between coupled nutrients is achievable. Because the goal of studying this phenomenon is to learn about the underlying causes of these biogeochemical cycles, being able to characterize the decoupling in a way that is easy to visualize is extremely important to the efficacy of this area of research. Variation between results is elaborated on as a caution towards carefully considered and consistent data manipulation. Calculating a difference between the coupled analytes after applying a scaling factor provided the most useful information about decoupling

Diffusion Coefficients Of N-Heptane And N-Decane In N-Alkanes And N-Alcohols At Several Temperatures

The diffusion coefficients of the solutes n-heptane and n-decane were measured in the series of alkane solvents n-hexane through n-decane and in the alcohol solvents n-hexanol and n-heptanol. Mutual and self-diffusivities in most cases were measured at the temperatures of 20°, 25°, 30°, and 40°C. Concentrations of the diffusion species were in the infinitely dilute region. An unsteady state porous frit technique was used with carbon-14 tagged diffusion species. The diffusion coefficients measured were compared with various liquid diffusivity prediction correlations. © 1974, American Chemical Society. All rights reserved