The Germination of Garden and Field Seeds

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Evaluating Drought Vulnerability of Small Community Surface Water Supply Systems in the Midwest

This report presents approaches and data availability for evaluating the drought vulnerability of small community water supply systems in the Midwest that obtain water from surface water bodies, such as rivers, streams, natural lakes, and man-made reservoirs. A description is provided of the various types of surface water sources from which 320 small community systems in the Midwest, each serving 10,000 or fewer people, obtain their water. The small community surface water system most commonly obtains its supply from one or two small impounding reservoirs. However, a substantial number of communities instead obtain their water from either direct river withdrawals or off-channel storage of water withdrawn from streams and rivers. Sixty of these 320 small community surface water systems were interviewed to gather information on the availability of data to determine the drought vulnerability of these systems. Although hydrologic and physical data exist for evaluating many of these systems, relatively few of the interviewed system managers could provide such pertinent information. A summary of selected hydrologic data is provided that can be used to determine the relative severity of major historical drought periods for various portions of the Midwest. Focus is given to historical droughts and available data for the southern portion of the Midwest where most surface water supply systems are located, comprising parts of Kansas, Missouri, Iowa, Illinois, Indiana, and Ohio. Geographic differences in drought severity are described, as is the influence of the physical characteristics of a water supply on the “critical” drought duration that a community must consider. Basic water budget analyses of water supplies and data needs are presented. Reservoir capacity measurements and estimates of inflow are the most critical data in reliable assessment of water supply adequacy. Depending on data availability, estimation of inflows may be straightforward to highly uncertain. For water supply systems that withdraw directly from a stream or river, the existence of long-term stream gage data on that river is particularly crucial to evaluate supply adequacy, and such data for larger streams and rivers are often available. With impounding reservoirs, which are typically located on smaller streams, data for that stream may often not exist; however, data from a “surrogate” gage that is considered to be hydrologically similar are often sufficient to estimate water supply yield. Systems that use off-channel reservoirs often withdraw water from smaller streams that do not have data for accurate depiction of their yield, and these systems also appear to be the most vulnerable to severe drought conditions. Case studies are presented to provide examples of yield calculations and innovative approaches that selected small communities have undertaken for addressing drought vulnerability. The role of demand management (drought response and water conservation) in evaluating drought vulnerability is also presented. If hydrologic data and basic physical data such as storage capacity are lacking, it may be difficult for either system managers or experienced professionals to estimate a community system’s yield and potential drought impacts, particularly for off-channel reservoir and low channel dam systems. However, managers should attempt to understand the type of drought period likely to test the adequacy of the available supply and can begin recording basic system observations, such as daily withdrawal records and reservoir drawdown, in a readily-accessible form that will be useful for future evaluations.published or submitted for publicationis peer reviewe

Optical and electrical activity of defects in rare earth implanted Si

A common technique for introducing rare earth atoms into Si and related materials for photonic applications is ion implantation. It is compatible with standard Si processing, and also allows high, non-equilibrium concentrations of rare earths to be introduced. However, the high energies often employed mean that there are collision cascades and potentially severe end-of-range damage. This paper reports on studies of this damage, and the competition it may present to the optical activity of the rare earths. Er-, Si, and Yb-implanted Si samples have been investigated, before and after anneals designed to restore the sample crystallinity. The electrical activity of defects in as-implanted Er, Si, and Yb doped Si has been studied by Deep Level Transient Spectroscopy (DTLS) and the related, high resolution technique, Laplace DLTS (LDLTS), as a function of annealing. Er-implanted Si, regrown by solid phase epitaxy at 600degrees C and then subject to a rapid thermal anneal, has also been studied by time-resolved photoluminescence (PL). The LDLTS studies reveal that there are clear differences in the defect population as a function of depth from the surface, and this is attributed to different defects in the vacancy-rich and interstitial-rich regions. Defects in the interstitial-rich region have electrical characteristics typical of small extended defects, and these may provide the precursors for larger structural defects in annealed layers. The time-resolved PL of the annealed layers, in combination with electron microscopy, shows that the Er emission at 1.54microns contains a fast component attributed to non-radiative recombination at deep states due to small dislocations. It is concluded that there can be measurable competition to the radiative efficiency in rare-earth implanted Si that is due to the implantation and is not specific to Er.</p

Improvements in Heat Transfer for Anti-Icing of Gas-Heated Airfoils with Internal Fins and Partitions

The effect of modifying the gas passage of hollow metal airfoils by the additIon of internal fins and partitions was experimentally investigated and comparisons were made among a basic unfinned airfoil section and two airfoil designs having metal fins attached at the leading edge of the internal gas passage. An analysis considering the effects of heat conduction in the airfoil metal was made to determine the internal modification effectiveness that may be obtained in gas-heated components, such as turbojet-inlet guide vanes, support struts, hollow propeller blades, arid. thin wings. Over a wide range of heated-gas flow and tunnel-air velocity, the increase In surface-heating rates with internal finning was marked (up to 3.5 times), with the greatest increase occurring at the leading edge where anti-icing heat requirements are most critical. Variations in the amount and the location of internal finning and. partitioning provided. control over the local rates of surface heat transfer and permitted efficient anti-icing utilization of the gas-stream heat content

What Collective Bargaining Promises and What it Does

[Excerpt] From the outset of my career in teaching, I have been deeply interested in the question of freedom. This interest is in part due to my upbringing and in part is the result of my academic training. Not only its substance but its origins, extension, and preservation have been abiding concerns. We often take freedom for granted, but quarrels and fights about its nature, conditions, and scope fill our history. Freedom had to be won. It was never, and is not now, established universally. It has had to be gained by groups who did not enjoy it. Such extensions as have been made were only by power of those who sought it. Freedom not only has had to be fought for, but, once gained, it has had to be maintained through constant defense. Eternal vigilance is the price of freedom

Flight control system design factors for applying automated testing techniques

Automated validation of flight-critical embedded systems is being done at ARC Dryden Flight Research Facility. The automated testing techniques are being used to perform closed-loop validation of man-rated flight control systems. The principal design features and operational experiences of the X-29 forward-swept-wing aircraft and F-18 High Alpha Research Vehicle (HARV) automated test systems are discussed. Operationally applying automated testing techniques has accentuated flight control system features that either help or hinder the application of these techniques. The paper also discusses flight control system features which foster the use of automated testing techniques

Icing Characteristics and Anti-Icing Heat Requirements for Hollow and Ternally Modified Gas-Heated Inlet Guide Vanes

A two-dimensional inlet-guide-vane cascade was investigated to determine the effects of ice formations on the pressure losses across the guide vanes and to evaluate the heated gas flow and temperature required to prevent Icing at various conditions. A gas flow of approximately 0.4 percent of the inlet-air flow was necessary for anti-icing a hollow guide-vane stage at an inlet-gas temperature of 500 F under the following icing conditions: air velocity, 280 miles per hour; water content, 0.9 gram per cubic meter; and Inlet-air static temperature, 00 F. Also presented are the anti-icing gas flows required with modifications of the hollow Internal gas passage, which show heatinput savings greater than 50 percent

Financial Risk in the Biotechnology Industry

The biotechnology industry has been an engine of innovation for the U.S. healthcare system and, more generally, the U.S. economy. It is by far the most research intensive industry in the U.S. In our analyses in the current paper, for example, we find that, over the past 25 years, average R&D intensity (R&D spending to total firm assets) for this industry was 38 percent. Consider that over this same period average R&D intensity for all industries was only about 3 percent. In the current paper we examine this industry along a number of dimensions and estimate its average financial risk. Specifically, we use Compustat and Center for Research in Securities Prices (CRSP) data from 1982 to 2005 for firms defined by the North American Industry Classification System (NAICS) as biotechnology firms to estimate several Fama-French three factor return models. The finance literature has established this model as the gold standard. Single factor models like the Capital Asset Pricing Model (CAPM) do not capture all of the types of systematic risk that influence firm cost of capital. In particular, the CAPM does not reflect the empirical evidence that supports both a size-related and a book-to-market related systematic risk factor . Both of these factors, based on biotech industry characteristics, will exert a greater influence on biotech firms, on average. Another implication is, of course, that cost of capital estimates for the industry will be underestimated when a single factor model, like the CAPM, is used. This also implies that the cost estimates of bringing a new drug and/or biologic to market will be understated if financial risk and cost of capital are measured using a single-factor model. In the current study we find that biotechnology firms are exposed to greater financial risk than other industries and are also more sensitive to policy shocks that affect, or could affect, industry profitability. Average nominal costs of capital over the 1982-2005 time period were 16.25 percent for biotechnology firms. Of course, these average estimates obscure significant variation in financial risk at the firm level, but nonetheless shed light on some interesting aggregate differences in risk. In the current paper we discuss the theoretical links between financial risk, stock prices and returns, and R&D spending. Several caveats are also discussed.

European Pharmaceutical Price Regulation, Firm Profitability, and R&D Spending

EU countries closely regulate pharmaceutical prices whereas the U.S. does not. This paper shows how price constraints affect the profitability, stock returns, and R&D spending of EU and U.S. firms. Compared to EU firms, U.S. firms are more profitable, earn higher stock returns, and spend more on research and development (R&D). Some differences have increased over time. In 1986, EU pharmaceutical R&D exceeded U.S. R&D by about 24 percent, but by 2004, EU R&D trailed U.S. R&D by about 15 percent. During these 19 years, U.S. R&D spending grew at a real annual compound rate of 8.8 percent, while EU R&D spending grew at a real 5.4 percent rate. Results show that EU consumers enjoyed much lower pharmaceutical price inflation, however, at a cost of 46 fewer new medicines introduced by EU firms and 1680 fewer EU research jobs.