Adaptation without natural selection

Document is itself an extended abstract

Note: estimating the charge size in explosive forming of sheet metal

Note: Estimating the charge size in explosive forming of sheet metal In the explosive forming of sheet metal some relatively easy method of estimating the size of the charge is needed. This short note describes a method in which the size of the charge is found by equating the work done in forming the component to that part of the explosive energy available for doing work on the component … [cont]

Imaging of Skeletal Metastases in Myxoid Liposarcoma

Unlike other soft tissue sarcomas, myxoid/round cell liposarcoma (MRCL) has a tendency to spread to extrapulmonary sites but bone metastases are thought to be uncommon. In case reports, negative bone scintigraphy has been noted in patients with myxoid/round cell liposarcoma and bone metastases but the prevalence and optimal method of diagnosis of bone metastases in this common subtype of liposarcoma are unclear. In an attempt to answer these questions, data were obtained from a prospective database of patients with sarcoma, including MRCL, and the diagnostic imaging used was examined. A variety of imaging tools were used including plain X-rays, bone scintigraphy, computed tomography (CT), and magnetic resonance imaging (MRI). Eight patients (4.3%) developed skeletal metastases all of which were positive on MRI. Bone scintigraphy was negative in two out of four cases, CT was negative in six out of seven, and X-rays were negative in four. Radiography and CT measure mainly cortical bone involvement, whereas MRI examines bone marrow. When investigating patients with MRCL for bone pain, negative X-rays and bone scans do not rule out bone metastases. In our experience, MRI provides the most sensitive technique for the diagnosis of bone metastases in MRCL

Hydrogen Utilization in the Electricity Sector: Opportunities, Issues, and Challenges

This is a modified version of an opinion piece that was featured in Power Engineering.When the sun is shining and the wind is blowing, solar and wind energy are the lowest cost sources of electric power in the country. This energy can be used to directly power electrical devices, such as lighting for buildings or charging electric vehicles. It can also be stored in batteries for short term storage or can be used to make hydrogen, which can be stored or put in a pipeline for later use, including users that are a long distance away. On the other hand, natural gas fi red gas turbines are both the lowest cost non-intermittent power source, and the largest source of electric power in the US, at around 40%. Can they continue to evolve and be repurposed to utilize stored hydrogen for electric power

Comparison of the telegraph and hyperdiffusion approximations in cosmic-ray transport

The telegraph equation and its generalizations have been repeatedly considered in the models of diffusive cosmic-ray transport. Yet the telegraph model has well-known limitations, and analytical arguments suggest that a hyperdiffusion model should serve as a more accurate alternative to the telegraph model, especially on the timescale of a few scattering times. We present a detailed side-by-side comparison of an evolving particle density profile, predicted by the telegraph and hyperdiffusion models in the context of a simple but physically meaningful initial-value problem, compare the predictions with the solution based on the Fokker–Planck equation, and discuss the applicability of the telegraph and hyperdiffusion approximations to the description of strongly anisotropic particle distributions

Experimental Space Weathering of Ordinary Chondrites by Nanopulse Laser: TEM Results

A set of ordinary chondrite meteorites has been subjected to artificial space weathering by nanopulse laser to simulate the effects of micrometeorite bombardment. Three meteorites, an H (Ehole), L (Chateau Renard - CR), and LL (Appley Bridge - AB) were lasered following the method of Sasaki et al [1]. Near IR spectra were taken before and after exposure to examine the optical changes induced and the samples were examined by scanning and transmission electron microscopy (SEM and TEM) to understand the physical changes