Contamination study

The time dependence of the angular reflectance from molecularly contaminated optical surfaces in the Vacuum Ultraviolet (VUV) is measured. The light scattering measurements are accomplished in situ on optical surfaces in real time during deposition of molecular contaminants. The measurements are taken using non-coherent VUV sources with the predominant wavelengths being the Krypton resonance lines at 1236 and 1600 A. Detection of the scattered light is accomplished using a set of three solar blind VUV photomultipliers. An in-plane VUV BRDF (Bidirectional Reflectance Distribution Functions) experiment is described and details of the ongoing program to characterize optical materials exposed to the space environment is reported

Behind at the Starting Line: Poverty Among Hispanic Infants

In this brief, authors Daniel Lichter, Scott Sanders, and Kenneth Johnson examine the economic circumstances of Hispanic infants using the Census Bureau’s American Community Survey annual microdata files from 2006 through 2010. They report that a disproportionate share of Hispanic infants start life’s race behind the starting line, poor and disadvantaged—an important finding because the proportion of all U.S. births that are Hispanic is growing rapidly. The poverty risk is especially high among rural Hispanic infants and those in new destinations. Despite higher poverty risks, Hispanic infants receive less governmental assistance. High Hispanic infant poverty has immediate and long-term consequences for infants and the nation. Failing to invest in families and children now has long-term consequences because early childhood poverty tends to set into motion a series of lifecycle disadvantages (such as insufficient parenting, bad neighborhoods, underfunded schools, and poor health care) that greatly increases the likelihood of poverty in adulthood. The authors conclude that whether today’s Hispanic children will assimilate into America’s economic mainstream is an open question, but the Hispanic infants who will help reshape America’s future require public policy attention now

Alternate method for achieving temperature control in the -160 to +90 Celcius range

A single-pass method for accurate and precise temperature control in the -160 to +90 C range is discussed. The method exhibited minimal set-point overshoot during temperature transitions. Control to +/-2 C with transitions between set-points of 7 C per minute were achieved. The method uses commercially available temperature controllers and a gaseous nitrogen/liquid nitrogen mixer to dampen the amplitude of cold temperature spikes caused by liquid nitrogen pulsing

What\u27s Required to Break the Beef per Acre Kentucky Record

As I approach the task that Garry assigned me, I ask the question, “Do I really want to attempt to produce 1400 or more pounds of beef per acre?” An easy answer is “yes,” but more likely “no.” Most farmers I know, full or part time have all they can do now and to reach record levels of anything requires much more time and management. I am going to attempt to discuss the steps I think that will be required to reach record breaking production. Higher gains are certainly possible. We know alfalfa can produce 8 to 10 tons of yield per acre, much more with irrigation. I will take a plant, animal, and management approach to address this issue

Rural Land-Use Trends in the Conterminous United States, 1950-2000.

In order to understand the magnitude, direction, and geographic distribution of land-use changes, we evaluated land-use trends in U.S. counties during the latter half of the 20th century. Our paper synthesizes the dominant spatial and temporal trends in population, agriculture, and urbanized land uses, using a variety of data sources and an ecoregion classification as a frame of reference. A combination of increasing attractiveness of nonmetropolitan areas in the period 1970–2000, decreasing household size, and decreasing density of settlement has resulted in important trends in the patterns of developed land. By 2000, the area of low-density, exurban development beyond the urban fringe occupied nearly 15 times the area of higher density urbanized development. Efficiency gains, mechanization, and agglomeration of agricultural concerns has resulted in data that show cropland area to be stable throughout the Corn Belt and parts of the West between 1950 and 2000, but decreasing by about 22% east of the Mississippi River. We use a regional case study of the Mid-Atlantic and Southeastern regions to focus in more detail on the land-cover changes resulting from these dynamics. Dominating were land-cover changes associated with the timber practices in the forested plains ecoregions and urbanization in the piedmont ecoregions. Appalachian ecoregions show the slowest rates of landcover change. The dominant trends of tremendous exurban growth, throughout the United States, and conversion and abandonment of agricultural lands, especially in the eastern United States, have important implications because they affect large areas of the country, the functioning of ecological systems, and the potential for restoratio

An alternate method for achieving temperature control in the -130 C to 75 C range

Thermal vacuum testing often requires temperature control of chamber shrouds and heat exchangers within the -130 C to 75 C range. There are two conventional methods which are normally employed to achieve control through this intermediate temperature range: (1) single-pass flow where control is achieved by alternately pulsing hot gaseous nitrogen (GN2) and cold LN2 into the feed line to yield the setpoint temperature; and (2) closed-loop circulation where control is achieved by either electrically heating or LN2 cooling the circulating GN2 to yield the setpoint temperature. A third method, using a mass flow ratio controller along with modulating control valves on GN2 and LN2 lines, provides excellent control but equipment for this method is expensive and cost-prohibitive for all but long-term continuous processes. The single-pass method provides marginal control and can result in unexpected overcooling of the test article from even a short pulse of LN2. The closed-loop circulation method provides excellent control but requires an expensive blower capable of operating at elevated pressures and cryogenic temperatures. Where precise control is needed (plus or minus 2 C), single-pass flow systems typically have not provided the precision required, primarily because of overcooling temperature excursions. Where several individual circuits are to be controlled at different temperatures, the use of expensive cryogenic blowers for each circuit is also cost-prohibitive, especially for short duration of one-of-a-kind tests. At JPL, a variant of the single-pass method was developed that was shown to provide precise temperature control in the -130 C to 75 C range while exhibiting minimal setpoint overshoot during temperature transitions. This alternate method uses a commercially available temperature controller along with a GN2/LN2 mixer to dampen the amplitude of cold temperature spikes caused by LN2 pulsing. The design of the GN2/LN2 mixer, the overall control system configuration, the operational procedure, and the prototype system test results are described

County-Specific Net Migration by Five-Year Age Groups, Hispanic Origin, Race and Sex 2000-2010

This report documents the methodology used to prepare county-level, net migration estimates by five-year age cohorts and sex, and by race and Hispanic origin, for the intercensal period from 2000 to 2010. The estimates were prepared using a vital statistics version of the forward cohort residual method (Siegel and Hamilton 1952) following the techniques used to prepare the 1990 to 2000 net migration estimates (Voss, McNiven, Johnson, Hammer, and Fuguitt 2004) as described in detail below. These numbers (and the net migration rates derivable from them) extend the set of decennial estimates of net migration that have been produced following each decennial census beginning with 1960 (net migration for the 1950s: Bowles and Tarver, 1965; 1960s: Bowles, Beale and Lee, 1975; 1970s: White, Mueser and Tierney, 1987; 1980s: Fuguitt, Beale, and Voss 2010; and 1990s: Voss, McNiven, Hammer, Johnson and Fuguitt, 2004)

Cultivating nutrition

"Over the past decade, donor-funded policies and programs designed to address undernutrition in the Global South have shifted away from agriculture-based strategies toward nutrient supplementation and food fortification programs. Given the potential benefits resulting from agriculture-based nutrition interventions, this study uses Q methodology to explore the views of a range of stakeholders from both developed and developing countries on the value of—and constraints related to—gender-sensitive, nutrition-oriented agricultural projects. The three distinct viewpoints that emerge from this exercise all support the use of agricultural strategies to improve nutrition and underline the importance of gender-sensitive approaches. The viewpoints differ, however, on the relative importance of nutrition education, the strategic use of nutrient supplementation and food fortification, and the degree to which agriculture-based approaches have an impact on nutrition. The findings indicate that there is common ground among a range of stakeholders—donors, researchers, policymakers, and program practitioners—on the benefits of agriculture and gender-sensitive strategies to improve nutrition. These areas of agreement can serve as a foundation for forging an effective integrative strategy to improve nutrition that includes gender-sensitive agricultural approaches." Authors' AbstractNutrition ,malnutrition ,Agriculture ,stakeholders ,Gender ,

Cultivating nutrition

"Over the past decade, donor-funded policies and programs designed to address undernutrition in the Global South have shifted away from agriculture-based strategies toward nutrient supplementation and food fortification programs. Given the potential benefits resulting from agriculture-based nutrition interventions, this study uses Q methodology to explore the views of a range of stakeholders from both developed and developing countries on the value of—and constraints related to—gender-sensitive, nutrition-oriented agricultural projects. The three distinct viewpoints that emerge from this exercise all support the use of agricultural strategies to improve nutrition and underline the importance of gender-sensitive approaches. The viewpoints differ, however, on the relative importance of nutrition education, the strategic use of nutrient supplementation and food fortification, and the degree to which agriculture-based approaches have an impact on nutrition. The findings indicate that there is common ground among a range of stakeholders—donors, researchers, policymakers, and program practitioners—on the benefits of agriculture and gender-sensitive strategies to improve nutrition. These areas of agreement can serve as a foundation for forging an effective integrative strategy to improve nutrition that includes gender-sensitive agricultural approaches." Authors' AbstractNutrition ,malnutrition ,Agriculture ,stakeholders ,Gender ,