356 research outputs found
Influence of Fertilizer Nitrogen and Sulfur on Production of Malting Barley
Studies in north-central Nebraska from 1975 through 1977: 1. Evaluated the malting barley production potential of the irrigated sandy soils of the region. 2. Measured the effect of application of N and S on yield and quality of barley grown for malting purposes. 3. Investigated the ability of N analysis of barley in the vegetative stage to predict protein content of grain at harvest. Data gathered lead to the following conclusions: 1. The potential for production of malting barley on irrigated sandy soils of north-central Nebraska is limited. 2. Yields increased with the application of fertilizer N throughout the study although response varied with site and variety. 3. Application of fertilizer S had no effect on yield throughout the study. 4. Application of N increased the protein content of all grain varieties studied by approximately 2 to 3 percent. 5. Analysis of plant material collected at the boot stage for N provided a reliable indication of the grain protein content
Warm-season Grass Establishment with Atrazine
Weed competition is a limiting factor in warm-season grass establishment often delaying the first forage harvest 2 or 3 years. Weed control with herbicides could reduce this competition resulting in more rapid grass establishment. Field experiments were conducted to evaluate the effect of atrazine [2-chloro-4-(ethylamino)-6-(isopropy1amino)- s-triazine] on weed control, warm-season grass establishment, and forage yield during the seeding and following year. Several warm-season grass species were spring seeded at locations having distinctly different soils. The soils involved were a Butler silty clay loam (Abruptic Argiaquoll) containing 3.8% organic matter and a pH of 5.2, a Crofton silty clay loam (Typic Ustorthent) containing 2.1% organic matter with a pH of 7.2 and a Nora silty clay loam (Udic Haplustoll) containing 2.8% organic matter and pH 5.8. Atrazine at various rates was applied preemergence shortly after grass seeding and at one site it was atso applied the preceding fall. Weed control, grass establishment, and forage yield were measured the year of seeding and the following year. Uncontrolled weeds during the year of seeding reduced stands and 1st year forage yields of big bluestem (Andropogon gerurdi Vitman), indiangrass [Sorghusfrum nutuns (L.) Nash], sand lovegrass [Emgrostis trkhodes (Nutt. j Wood], sideoats grama [Bouteloua curtipendula (Michx.) Torr.], and switchgrass (Panicum virgatum L.). Big bluestem and switchgrass tolerated preemergence atrazine applications of 3.4 kgha on the Butler soil. Big bluestem was less tolerant of atrazine than switchgrass on the Crofton soil. Some atrazine tolerance was present in indiangrass but not in sand lovegrass and sideoats grama. Seeding year forage yields of big bluestem and switchgrass were significantly increased by atrazine. Weed control during the seeding year sometimes resulted in higher forage yields the following year. Big bluestem and switchgrass can he readily established and produce substantial forage yields the year of seeding by using atrazine for weed control. This would make these grasses more attractive to farmers and ranchers
Fatigue in U.S. Astronauts Onboard the International Space Station: Environmental Factors, Operational Impacts, and Implementation of Countermeasures
Since 2000, US astronauts have been supporting missions up to a six month duration on the International Space Station (ISS). Crewmembers have experienced fatigue for reasons similar to military deployments. Astronauts experience psychological stressors such as heavy workloads, extended duty periods, circadian misalignment, inadequate/ineffective sleep, and loss of the environmental cues of a gravity environment. Complicating the psychological stressors are environmental factors; distracting background noise, unexpected and variable mission schedules, unfavorable thermal control, elevated CO2 levels, and an unusual sleep environment with schedules that impinge on presleep periods. Physiological contributors to poor sleep and fatigue include a cephalad fluid shift and back pain. Restful sleep is further challenged due to a lack of gravityrelated proprioceptive cues and need for restraints. The term "space fog" has been used by astronauts to describe a phenomenon of forgetfulness, slowed reaction time and transient confusion while trying to complete tasks. There is a distinct temporal correlation with arrival on the Space Station and the onset of slowed cognitive skills and a spontaneous resolution that may take up to 6 weeks. The Genesis of this phenomenon may be chronic fatigue secondary to transitioning from a planar environment to a 360deg microgravity perspective. Recently, countermeasures to improve sleep duration and quality in astronauts on the ISS have been instituted with moderate degrees of success as measured by selfreaction time (psychomotor vigilance task testing), actigraphy, and subjective reports. Judicious use of stimulants and hypnotics, light therapy, controlled sleep periods and sleep shifting and reducing ambient CO2 levels are a few of the most promising countermeasures being used in space to improve sleep and reduce fatigue
EC89-104 Nebraska Soybean Variety Tests 1989
Extension circular 89-104 is about Nebraska soybean variety tests 1989
Soybean Chlorosis Studies on High pH Bottomland Soils
Soybean varieties are different in tolerance to lime-induced chlorosis. Field trials were conducted to evaluate variety performance on soils where chlorosis in soybeans was a known problem. Thirty-six varieties out of 177 were identified as tolerant to soil conditions that cause chlorosis. Eleven varieties of these 36 were found to have the most consistent yield performance on high pH soils. Tolerant varieties must be planted at adequate densities for best performance. A seeding rate of 13.5 seeds per foot of row, the highest seeding rate employed, did not appear to maximize yield on soils where chlorosis was severe. On some soils, chlorosis is so severe that even tolerant varieties planted at adequate densities will not produce seed. Under conditions where soils cause moderate to severe chlorosis in tolerant varieties, yields were improved by the use of a high pH stable chelate (Fe-EDDHA) with the seed
Soybean Chlorosis Studies on High pH Bottomland Soils
Soybean varieties are different in tolerance to lime-induced chlorosis. Field trials were conducted to evaluate variety performance on soils where chlorosis in soybeans was a known problem. Thirty-six varieties out of 177 were identified as tolerant to soil conditions that cause chlorosis. Eleven varieties of these 36 were found to have the most consistent yield performance on high pH soils. Tolerant varieties must be planted at adequate densities for best performance. A seeding rate of 13.5 seeds per foot of row, the highest seeding rate employed, did not appear to maximize yield on soils where chlorosis was severe. On some soils, chlorosis is so severe that even tolerant varieties planted at adequate densities will not produce seed. Under conditions where soils cause moderate to severe chlorosis in tolerant varieties, yields were improved by the use of a high pH stable chelate (Fe-EDDHA) with the seed
Behavioral Health and Performance Operations During the Space Shuttle Program
Prior to the Columbia STS 107 disaster in 2003, the Johnson Space Center s Behavioral Health and Performance Group (BHP) became involved in Space Shuttle Operations on an as needed basis, occasionally acting as a consultant and primarily addressing crew-crew personality conflicts. The BHP group also assisted with astronaut selection at every selection cycle beginning in 1991. Following STS 107, an event that spawned an increased need of behavioral health support to STS crew members and their dependents, BHP services to the Space Shuttle Program were enhanced beginning with the STS 114 Return to Flight mission in 2005. These services included the presence of BHP personnel at STS launches and landings for contingency support, a BHP briefing to the entire STS crew at L-11 months, a private preflight meeting with the STS Commander at L-9 months, and the presence of a BHP consultant at the L-1.5 month Family Support Office briefing to crew and family members. The later development of an annual behavioral health assessment of all active astronauts also augmented BHP s Space Shuttle Program specific services, allowing for private meetings with all STS crew members before and after each mission. The components of each facet of these BHP Space Shuttle Program support services will be presented, along with valuable lessons learned, and with recommendations for BHP involvement in future short duration space mission
World Scientists’ Warning of a Climate Emergency
Scientists have a moral obligation to clearly warn humanity of any catastrophic threat and to “tell it like it is.” On the basis of this obligation and the graphical indicators presented below, we declare, with more than 11,000 scientist signatories from around the world, clearly and unequivocally that planet Earth is facing a climate emergency
Multiple metrics for quantifying the intensity of water consumption of energy production
Discussion of the environmental implications of worldwide energy demand is currently dominated by the effects of carbon dioxide (CO[subscript 2]) emissions on global climate. At the regional scale, however, water resource challenges associated with energy systems are a growing concern. This paper, based on an inventory of national energy portfolios, posits an indicator-based framework for characterizing regional energy portfolios' relative water intensity. These calculations extend upon a previous paper that established a method for calculating the national water consumption of energy production (WCEP) at the global level. Intensity indicators are based on normalizing the WCEP results with a set of additional indicators (including population, gross domestic product, total energy production, and regional water availability). The results show great variability in water consumption across nations, as well as across the various water intensity measures that were applied. Therefore, it is best to apply this full suite of indicators to each country to develop an integrated understanding of the intensity of water use for energy across countries
The water consumption of energy production: an international comparison
Producing energy resources requires significant quantities of fresh water. As an energy sector changes or expands, the mix of technologies deployed to produce fuels and electricity determines the associated burden on regional water resources. Many reports have identified the water consumption of various energy production technologies. This paper synthesizes and expands upon this previous work by exploring the geographic distribution of water use by national energy portfolios. By defining and calculating an indicator to compare the water consumption of energy production for over 150 countries, we estimate that approximately 52 billion cubic meters of fresh water is consumed annually for global energy production. Further, in consolidating the data, it became clear that both the quality of the data and global reporting standards should be improved to track this important variable at the global scale. By introducing a consistent indicator to empirically assess coupled water–energy systems, it is hoped that this research will provide greater visibility into the magnitude of water use for energy production at the national and global scales
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