65 research outputs found
THE EFFECTS OF ALTERNATE COW FRESHENING DISTRIBUTIONS ON MILK PRODUCTION AND IMPORTS IN FLORIDA
Seasonal swings in milk production in Florida result in a need to import milk on a seasonal basis. A linear programming analysis is used to analyze alternate freshening-date distributions and project the cost savings to Florida dairy farmers from reduced milk imports.Farm Management,
Recommended from our members
Soil domestication by rice cultivation results in plant-soil feedback through shifts in soil microbiota.
BackgroundSoils are a key component of agricultural productivity, and soil microbiota determine the availability of many essential plant nutrients. Agricultural domestication of soils, that is, the conversion of previously uncultivated soils to a cultivated state, is frequently accompanied by intensive monoculture, especially in the developing world. However, there is limited understanding of how continuous cultivation alters the structure of prokaryotic soil microbiota after soil domestication, including to what extent crop plants impact soil microbiota composition, and how changes in microbiota composition arising from cultivation affect crop performance.ResultsWe show here that continuous monoculture (> 8 growing seasons) of the major food crop rice under flooded conditions is associated with a pronounced shift in soil bacterial and archaeal microbiota structure towards a more consistent composition, thereby domesticating microbiota of previously uncultivated sites. Aside from the potential effects of agricultural cultivation practices, we provide evidence that rice plants themselves are important drivers of the domestication process, acting through selective enrichment of specific taxa, including methanogenic archaea, in their rhizosphere that differ from those of native plants growing in the same environment. Furthermore, we find that microbiota from soils domesticated by rice cultivation contribute to plant-soil feedback, by imparting a negative effect on rice seedling vigor.ConclusionsSoil domestication through continuous monoculture cultivation of rice results in compositional changes in the soil microbiota, which are in part driven by the rice plants. The consequences include a negative impact on plant performance and increases in greenhouse gas emitting microbes
Laminating Creosote-Treated Hardwoods
A study was conducted to investigate the bondability of four selected hardwood species after being treated with creosote. A completely randomized block factorial design was employed. Experimental factors included five wood species (chestnut oak, red oak, red maple, yellow-poplar, and southern pine), five adhesive systems (elevated temperature cure phenol-resorcinol-formaldehyde, room temperature cure phenol-resorcinol-formaldehyde, resorcinol-formaldehyde, emulsion polymer isocyanate, and low-viscosity formulation emulsion polymer isocyanate) and two exposure levels (ambient room and vacuum/pressure/soak conditions). Exposure levels effects on the different wood species resulted in highly variable adhesive system performance. Exposure level effects were most evident for the higher density oaks. Shear strength and percent wood failure results for all wood species revealed a general trend towards a higher performance for the two phenol-resorcinol-formaldehyde systems. Res-orcinol-based adhesive systems had the highest shear strength values. Percent wood failure values were highest for the elevated temperature cure phenol-resorcinol-formaldehyde system for all species. Elevated temperature cure adhesive systems appeared to be required to successfully bond high-density creosote treated species. Successful bonding of medium-density species can be accomplished at room temperatures given proper adhesive system selection
Normas percibidas por los estudiantes universitarios de enfermerĂa acerca de sus pares y el uso de drogas en Lima, PerĂş
Design and construction of the MicroBooNE detector
This paper describes the design and construction of the MicroBooNE liquid
argon time projection chamber and associated systems. MicroBooNE is the first
phase of the Short Baseline Neutrino program, located at Fermilab, and will
utilize the capabilities of liquid argon detectors to examine a rich assortment
of physics topics. In this document details of design specifications, assembly
procedures, and acceptance tests are reported
Recommended from our members
Telemetry in an Automated Water Supply Control System
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, CaliforniaThe White Sands Missile Range (WSMR) Water Supply Control System (WSCS) controls and monitors the water wells, tanks and booster pumps located at the southern end of the missile range. Figure 1 is an overview of the WSMR water supply system. The WSCS provides water for approximately 90 square miles of the 3,700 square mile missile range. The WSCS was designed and installed in 1990 and in need of upgrading and repair. The system was evaluated and found to be only moderately functional. The WSCS consists of an IBM compatible personal computer (PC) based user interface, located at the WSMR Water Plant and Fire Dept. and industrial-type computers called Programmable Logic Controller (PLC) based stations at the Water Plant, water wells and tanks. The stations communicate over a 400 MHz radio half-duplex link. The serial message utilizes the Cyclic Redundancy Check (CRC) and Block Check Character (BBC) type of error checking. The Master station controls pumping by downloading pump settings to the slave stations. The slave stations upload data to the master such as tank level, pump status, energy usage, gallons of water pumped and various alarms. The system was analyzed and the design was found to be sound. The system did require improvements. These improvements include adding surge suppressors, software upgrades, absolute reading flow rate sensors, and providing adequate environmental cooling for the control system. Procedures for periodic maintenance and calibration of the sensors and schedules for radio equipment maintenance were also developed. Software modifications to reduce WSMR energy usage by reducing pumping during peak energy demand times are being integrated into the WSCS. The peak energy demand times are determined by historical energy usage data.International Foundation for TelemeteringProceedings from the International Telemetering Conference are made available by the International Foundation for Telemetering and the University of Arizona Libraries. Visit http://www.telemetry.org/index.php/contact-us if you have questions about items in this collection
A Comprehensive Analysis of Macroinvertebrate Diversity on the Susquehanna River at the Byers Island Transect From 2009 to 2012
The Susquehanna River ecosystem has been monitored for macroinvertebrate composition during the summer months of 2009, 2010, and 2012. Macroinvertebrates are signi?cant determinants of stream health based on how sensitive they are to pollution. Our stud
- …