Radium content of ocean bottom sediments from the Arctic Ocean, Bering Sea, Alaska Peninsula, and the coasts of southern Alaska and western Canada

The radium content of several surface bottom samples in the region of the San Juan Archipelago and Vancouver Island have been reported previously (15). The present paper deals with the radium content of both surface bottom and core samples taken along the Pacific . coast of Canada and the coast of Alaska, in the Pacific Ocean, Bering Sea and the Arctic Ocean

Periodic changes in spectral scattering and spectral transmission of daylight in tidal water

Seasonal changes in the transmission of certain spectral bands of solar radiation in the inshore waters of the Pacific Northwest were reported by Williams and Utterback (1) for the year 1934 and by tterback and l\1iller (2) for the years 1935 and 1936…

Radium analyses of marine sediments in Northern Pacific and adjacent waters

Although systematic soundings of the ocean bottom were initiated approximately 100 years ago, and although the United States Coast and Geodetic Survey took hundreds of ocean bottom samples beginning about 75 years ago, it was not until the ship CARNEGIE collected a number of bottom samples at great depths that information began to be available on the radioactive properties of deep ocean sediments...

Radium content of some inshore bottom samples in the Pacific Northwest

The radium content of ordinary rock formations is quite well established and has been summarized by J efferys (3). However, a comparatively few radium determinations have been made on samples taken from the ocean bottom. Joly (4) has reported twelve radium determinations of surface samples collected from the Atlantic and Pacific Oceans. Pettersson (5) has reported on determinations made on twenty-eight samples, most of them taken from the Atlantic Ocean, while Piggott (6) has reported on twenty-eight samples t aken largely from the Pacific Ocean. Evans (1) has reported on one sample taken from off the Coast of California

Characterization of plant-based protein sources for use in canine and feline nutrition

The objective of this study was to determine the macronutrient composition and standardized amino acid digestibility of 14 novel, plant-based, protein sources. The 14 protein sources are comprised of protein concentrates (pea, potato, faba bean, yeast, and soy concentrates), pulses (garbanzo beans, navy beans, black beans, lentils, and peas), and byproducts (corn gluten meal, peanut flour, soybean meal, and soy flakes). Macronutrient compositions and a complete amino acid profile were analyzed for all 14 protein sources. Cecectomized roosters (n=4/treatment) were utilized in a precision-fed rooster assay to measure standardized amino acid digestibility and true metabolizable energy corrected for nitrogen (TMEn). The roosters were precision-fed 30g of a 1:1 ratio of an ingredient and corn mixture. Excreta was collected after 48h, freeze-dried, and analyzed for a complete amino acid profile. Due to the high amino acid digestibility and well-balanced essential amino acid profiles, these plant-based proteins have the potential to become viable protein sources in canine and feline diets

Exploration and exploitation in the presence of network externalities

This paper examines the conditions under which exploration of a new, incompatible technologyis conducive to firm growth in the presence of network externalities. In particular, this studyis motivated bythe divergent evolutions of the PC and the workstation markets in response to a new technology: reduced instruction set computing (RISC). In the PC market, Intel has developed new microprocessors bymaintaining compatibilitywith the established architecture, whereas it was radicallyr eplaced byRISC in the workstation market. History indicates that unlike the PC market, the workstation market consisted of a large number of power users, who are less sensitive to compatibilitythan ordinaryusers. Our numerical analysis indicates that the exploration of a new, incompatible technologyis more likelyto increase the chance of firm growth when there are a substantial number of power users or when a new technologyis introduced before an established technologytakes off. (; ; ;

Dust detection by the wave instrument on STEREO: nanoparticles picked up by the solar wind?

The STEREO/WAVES instrument has detected a very large number of intense voltage pulses. We suggest that these events are produced by impact ionisation of nanoparticles striking the spacecraft at a velocity of the order of magnitude of the solar wind speed. Nanoparticles, which are half-way between micron-sized dust and atomic ions, have such a large charge-to-mass ratio that the electric field induced by the solar wind magnetic field accelerates them very efficiently. Since the voltage produced by dust impacts increases very fast with speed, such nanoparticles produce signals as high as do much larger grains of smaller speeds. The flux of 10-nm radius grains inferred in this way is compatible with the interplanetary dust flux model. The present results may represent the first detection of fast nanoparticles in interplanetary space near Earth orbit.Comment: In press in Solar Physics, 13 pages, 5 figure

Churn, Baby, Churn: Strategic Dynamics Among Dominant and Fringe Firms in a Segmented Industry

This paper integrates and extends the literatures on industry evolution and dominant firms to develop a dynamic theory of dominant and fringe competitive interaction in a segmented industry. It argues that a dominant firm, seeing contraction of growth in its current segment(s), enters new segments in which it can exploit its technological strengths, but that are sufficiently distant to avoid cannibalization. The dominant firm acts as a low-cost Stackelberg leader, driving down prices and triggering a sales takeoff in the new segment. We identify a “churn” effect associated with dominant firm entry: fringe firms that precede the dominant firm into the segment tend to exit the segment, while new fringe firms enter, causing a net increase in the number of firms in the segment. As the segment matures and sales decline in the segment, the process repeats itself. We examine the predictions of the theory with a study of price, quantity, entry, and exit across 24 product classes in the desktop laser printer industry from 1984 to 1996. Using descriptive statistics, hazard rate models, and panel data methods, we find empirical support for the theoretical predictions