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... Phytophthora spp. are pathogenic to many plant species worldwide, and late blight, caused by Phytophthora infestans, and pink rot, caused by P. erythroseptica, are two important diseases of potato. Another Phytophthora sp., P. nicotianae, was recovered from pink-rot-symptomatic tubers collected from commercial fields in Nebraska, Florida, and Missouri in 2005, 2006, and 2007, respectively. P. nico ...
... From December 2005 through January 2006, the Minnesota Department of Health (MDH) identified four human clinical isolates of Salmonella Typhimurium that were indistinguishable by pulsed-field gel electrophoresis (PFGE). During routine interviews, three of the cases reported attending the same junior high school and two handled snakes in the science classroom. MDH collected environmental samples fr ...
... OBJECTIVE:--The purpose of this study was to determine the independent and joint associations of cardiorespiratory fitness (CRF) and BMI with the incidence of type 2 diabetes in women. RESEARCH DESIGN AND METHODS--An observational cohort of 6,249 women aged 20-79 years was free of baseline cardiovascular disease, cancer, and diabetes. CRF was measured using a maximal treadmill exercise test. BMI w ...
sympatry; geographical distribution; insect taxonomy; hybrids; loci; interspecific hybridization; genetic variation; reproductive isolation; Allonemobius; allozymes; new species; population structure; Texas; Southeastern United States
Abstract:
... This study investigates the zone of overlap and hybridization between a new species in the Allonemobius species complex and Allonemobius socius (Scudder 1877). The new species, Allonemobius sp. nov. Tex was previously misidentified as Allonemobius fasciatus (De Geer 1773). Our survey of genetic variation at 13 allozyme loci shows that the new species differs from A. fasciatus in at least two alloz ...
... Summer-dormant, cool-season perennial grasses are being used in place of traditional, summer-active cultivars for high-quality winter forage. One reason for this change is the ability of cultivars with summer-dormant attributes to tolerate increasing annual temperature, decreasing precipitation, and repeated severe summer droughts. The mechanism of summer dormancy is still not understood in detail ...
urban areas; Latrodectus geometricus; prevalence; venoms; public health; risk assessment; incidence; epidemiological studies; geographical distribution; insect bites and stings; introduced species; population size; geographical variation; Louisiana; Texas; Mississippi; Florida; Georgia
Abstract:
... The range of the brown widow spider Latrodectus geometricus C. L. Koch includes much of Africa and South and Central America. This medically important spider has been recently introduced to Japan, Indonesia, Papua New Guinea, Australia, Hawaii, and California. After the identification of the brown widow spider in New Orleans, LA, and southern Mississippi, surveys in the southeastern United States ...
... Redberry juniper (Juniperus pinchotii Sudworth) is an invasive, evergreen tree that is rapidly expanding throughout western and central Texas. Goats will consume some juniper on rangelands; however, intake is limited. The objective of our research was to determine how the age and body condition of goats influence their consumption of juniper and an artificial feed containing 4 monoterpenes. Two se ...
beef cattle; concentrated animal feeding operations; feedlots; ammonia; urine; feces; ammonium nitrogen; gas emissions; summer; winter; seasonal variation; air pollution; air quality; wind speed; air temperature; quantitative analysis; stochastic processes; statistical models; Texas; High Plains (United States)
Abstract:
... Concentrated animal feeding operations (CAFOs) are major sources of ammonia emitted into the atmosphere. There is considerable literature on ammonia emissions from poultry and swine CAFO, but few comprehensive studies have investigated large, open lot beef cattle feedyards. Ammonia emission rates and emission factors for a 77-ha, 45 000-head commercial beef cattle feedyard on the southern High Pla ...
... An important aspect of river science and management is the identification of key boundaries, transition zones and hinge points. Such critical areas are likely to be important foci or indicators of the effects of environmental change on river systems. While geological controls on such features are widely recognized in upland streams, inherited or antecedent forms may also be important controls of k ...
Beier, Ross C.; Duke, Sara E.; Ziprin, Richard L.; Harvey, Roger B.; Hume, Michael E.; Poole, Toni L.; Scott, H. Morgan; Highfield, Linda D.; Alali, Walid Q.; Andrews, Kathleen; Anderson, Robin C.; Nisbet, David J.
... Vancomycin-resistant Enterococcus faecium (VRE) from human wastewater effluents in a nonclinical semiclosed agri-food system in Texas were characterized for susceptibility to antibiotics and disinfectants. The 50 VRE were resistant to eight fluoroquinolones and 10 of 17 antimicrobials typically active against Gram-positive organisms. The VRE were susceptible to quinupristin/dalfopristin and linezo ...
Gossypium hirsutum; cotton; fiber crops; staple (fibers); length; spinning; crop quality; information sources; information systems; cultivars; diameter; genotype; environmental factors; advanced fiber information system; Texas
Abstract:
... Varying fiber length distributions of cotton, Gossypium hirsutum L., impacts its spinning performance. Advanced Fiber Information System (AFIS) facilitates the analysis of the length distribution of individual fibers in cotton. Quantile regression is a variant of standard regression with which conditional quantile values can be calculated by minimizing weighted sums of absolute deviations across t ...
groundwater extraction; aquifers; time series analysis; groundwater; Texas
Abstract:
... Long-term time series data of aquifer recharge, groundwater extraction, and discharge are used to estimate aquifer storage capacity and maximum annual yield. Aquifer storage capacity is defined as the maximum volume of water that can be stored in an aquifer. It is estimated using a transient water-balance approach. The maximum annual yield is defined as the maximum combined groundwater extraction ...
Soil and Water Assessment Tool model; anthropogenic activities; ecosystems; lakes; land cover; landscapes; meteorological data; nitrates; nitrogen; nitrogen fixation; phytoplankton; pollution load; regression analysis; soil; stream flow; summer; topography; water temperature; watersheds; Texas
Abstract:
... N₂ fixation can be an important source of N to limnetic ecosystems and can influence the structure of phytoplankton communities. However, watershed‐scale conditions that favor N₂ fixation in lakes and reservoirs have not been well studied. We measured N₂ fixation and lacustrine variables monthly over a 19‐month period in Waco Reservoir, Texas, USA, and linked these data with nutrient‐loading estim ...
... Veterinarians play a unique role in emergency preparedness and response, and federal agencies and academic institutions therefore allocate considerable resources to provide training to enhance their readiness. However, the level of preparedness of veterinarians in many rural regions is yet to be improved. This article reports an assessment of the bioterrorism preparedness, specifically the experie ...
suburban areas; watersheds; turf grasses; sod strips; best management practices; composted manure; dairy manure; water pollution; phosphorus; pollution load; water quality; Soil and Water Assessment Tool model; Texas
Abstract:
... The disposal of manure on agricultural land has caused water quality concerns in many rural watersheds, sometimes requiring state environmental agencies to conduct total maximum daily load (TMDL) assessments of stream nutrients, such as nitrogen (N) and phosphorus (P). A best management practice (BMP) has been developed in response to a TMDL that mandates a 50% reduction of annual P load to the No ...
Farnsworth, Charles C.; Herman, James D.; Osterstock, Jason B.; Porterpan, Brandy L.; Willard, Michael D.; Hooper, R. Neil; Roussel, Allen J. Jr.; Schmitz, David G.; Fogelberg, Katherine; Kochevar, Deborah T.
... The middle Brazos River, located in east-central Texas, is a meandering lowland river with many oxbow lakes on its flood plain. Flood dynamics of the Brazos River are aseasonal, and faunal exchange during lateral connections of the main river channel and oxbows is pulse-like and occurs only during floods that may be months or years apart. Patterns of resource use among sympatric gar species (Lepis ...
... We used a combination of methods to study the reproductive ecology of the imperiled smalleye shiner Notropis buccula Cross in the Brazos River, Texas between April 2003 and March 2005. Patterns in oocyte development, gonadosomatic index and oocyte size distribution indicate that reproduction occurs over a 6-month period between April and September and that the population spawns asynchronously with ...
... Data collected in a general population survey from a random sample of individuals in two rural communities in Texas were used to examine the association between religious involvement and civic participation empirically. Support was found for the hypothesis that attendance at religious meetings is positively associated with community involvement. Results of the analysis of covariance also suggest t ...
Soil and Water Assessment Tool model; watershed hydrology; simulation models; case studies; Texas
Abstract:
... SWAT is a physically based model that can simulate water quality and quantity at the watershed scale. Due to many of the processes involved in the manual- or autocalibration of model parameters and the knowledge of realistic input values, calibration can become difficult. An autocalibration-sensitivity analysis procedure was embedded in SWAT version 2005 (SWAT2005) to optimize parameter processing ...
irrigation scheduling; automation; temperature; duration; thermometers; remote sensing; leaves; crops; canopy; growing season; water content; soybeans; Glycine max; water use efficiency; Texas
Abstract:
... A center pivot was completely automated using the temperature-time-threshold method of irrigation scheduling. An array of infrared thermometers was mounted on the center pivot, and these were used to remotely determine the crop leaf temperature as an indicator of crop water stress. We describe methods used to automatically collect and analyze the canopy temperature data and control the moving irri ...
... The objectives of our study were to determine prevalence of avian influenza viruses (AIV) on wintering grounds on the Texas Gulf Coast, USA, and to compare real-time reverse-transcriptase polymerase chain reaction (rRT-PCR) and virus isolation for detection of AIV in cloacal swabs from wild waterfowl. Cloacal swabs were collected from hunter-harvested waterfowl from November 2005 to January 2006 a ...
... We report the development of an enzyme-linked immunosorbent assay (ELISA) for detecting antibodies to Balamuthia mandrillaris, a free-living ameba that is an etiologic agent of granulomatous amebic encephalitis (GAE). As part of the California Encephalitis Project (CEP), we have tested serum and cerebrospinal fluid (CSF) samples from a subgroup of 130 hospitalized encephalitis patients (out of ~43 ...
... Onion and shallot (Allium cepa L.) exhibit wide variation in bulb fructan content, and the Frc locus on chromosome 8 conditions much of this variation. To understand the biochemical basis of Frc, we conducted biochemical and genetic analyses of Allium fistulosum (FF)-shallot (A. cepa Aggregatum group) alien monosomic addition lines (AALs; FF+1A-FF+8A) and onion mapping populations. Sucrose and fru ...
viral diseases of animals and humans; doves; phylogeny; Avian orthoavulavirus 1; wild birds; bird diseases; virulence; pigeons; Rhode Island; Texas
Abstract:
... As part of West Nile virus surveillance programs in Rhode Island and eastern Texas between 2000 and 2007, brain tissue was collected from 5,608 dead birds representing 21 avian orders found in public places or reported by homeowners. Fifteen Newcastle disease virus isolates were recovered only from birds of the order Columbiformes and were positively identified by the USDA-validated real-time reve ...
... Large numbers of a cockroach that resembled the German cockroach, Blattella germanica (L.), were observed during winter 2005-2006 in home turf settings in Weslaco, TX, 11 km from the U.S. border with northeastern Mexico. In June and July 2006, this cockroach was observed at night on the foliage of soybean, Glycine max (L.) Merr., in numbers often exceeding 50 per m row. Because of its similarity t ...
... Bottom-water hypoxia effects on sediment–water interface nitrogen (N) transformations in Corpus Christi Bay (TX, USA) were examined using continuous-flow intact sediment core incubations. Sediment cores were collected from three sites in August 2002 (summer hypoxia) and April 2003 (normoxia). Oxygen (O₂) and hydrogen sulfide (H₂S) depth profiles were generated with microelectrodes. Membrane inlet ...
Paula Federico; Thomas G. Hallam; Gary F. McCracken; S. Thomas Purucker; William E. Grant; A. Nelly Correa-Sandoval; John K. Westbrook; Rodrigo A. Medellín; Cutler J. Cleveland; Chris G. Sansone; Juan D. López Jr.; Margrit Betke; Arnulfo Moreno-Valdez; Thomas H. Kunz
... During the past 12 000 years agricultural systems have transitioned from natural habitats to conventional agricultural regions and recently to large areas of genetically engineered (GE) croplands. This GE revolution occurred for cotton in a span of slightly more than a decade during which a switch occurred in major cotton production areas from growing 100% conventional cotton to an environment in ...
... Fatty acid esters extractable from the surface of honey bee, Apis mellifera L. (Hymenoptera: Apidae), larvae, called brood pheromone, significantly increase rate of colony growth in the spring and summer when flowering plant pollen is available in the foraging environment. Increased colony growth rate occurs as a consequence of increased pollen intake through mechanisms such as increasing number o ...
biogeography; cacti and succulents; indigenous species; species diversity; Chihuahuan Desert; Texas
Abstract:
... A standardized sampling method was used to evaluate turnover (β diversity) among cactus species assemblages along a 798 km long latitudinal megatransect across the Chihuahuan Desert Region, from north-central Mexico to southern Texas. A total of 71 cactus species were found along the megatransect, 66.2% of which appeared at low frequencies, mostly as a consequence of their highly discontinuous dis ...
gas exchange; drought; seasonal variation; C3 plants; forbs; grasslands; carbon dioxide; perennials; water stress; photosynthesis; leaves; C4 plants; botanical composition; leaf area; radiation use efficiency; atmospheric circulation; cell respiration; environmental factors; net ecosystem exchange; rain; grazing intensity; Texas
Abstract:
... Eddy covariance measurements were begun in late April 2004 to quantify CO₂ exchange in a perennial C₃/C₄ grassland on the Edwards Plateau near San Marcos, TX. Objectives were to document how net ecosystem exchange of CO₂ (NEE) and its components, gross photosynthesis (GPP) and ecosystem respiration (R e), vary on a seasonal and interannual basis, and to examine how environmental factors affect C e ...
... The western Corn Belt and southwestern corn growing areas have highly variable year-to-year corn yields due to variation in rainfall and variation in frequency of high temperatures during the growing season. Irrigation is practiced at many locations to stabilize year-to-year yield variation. Early planting is desirable since higher temperatures coupled with less rainfall occur more frequently as t ...
climate; climate models; global warming; linear models; nonlinear models; prediction; renal calculi; risk; temperature; California; Florida; Kansas; Kentucky; Texas
Abstract:
... An unanticipated result of global warming is the likely northward expansion of the present-day southeastern U.S. kidney stone "belt." The fraction of the U.S. population living in high-risk zones for nephrolithiasis will grow from 40% in 2000 to 56% by 2050, and to 70% by 2095. Predictions based on a climate model of intermediate severity warming (SRESa1b) indicate a climate-related increase of 1. ...
kriging; estimation; pressure; cluster analysis; aquifers; groundwater; Texas; New Mexico
Abstract:
... Most applications of geostatistical estimation and simulation techniques are concerned with casting the kriging system for the entire data set. Although there have been many successful applications of geostatistical analysis to capture the nonlinear relationships inherent in hydrological processes, there are numerous instances where more data does not necessarily imply better performance. In this ...
... The Lower Rio Grande Valley (LRGV) of south Texas is an agriculturally rich area supporting intensive production of vegetables, fruits, grain sorghum, and cotton. Modern agricultural practices involve the combined use of irrigation with the application of large amounts of agrochemicals to maximize crop yields. Intensive agricultural activities in past decades might have caused potential contaminat ...
... Common broomweed (Amphiachyris dracunculoides [[DC]] Nutt. Ex Rydb.) is an annual forb that occurs throughout the southern Great Plains, USA. During years of abundant growth, broomweed is problematic because it can reduce grass production and interfere with livestock foraging. In contrast, the canopy structure of broomweed may provide habitat cover for wildlife, including the northern bobwhite qua ...
... Although invaders come in all shapes and sizes, several mollusks have recently achieved notoriety as both economically and ecologically costly invaders. Applesnails of the genus Pomacea get their name from reaching the size of an apple. Native to South America, the species P. insularum has recently established reproducing, and potentially invasive, populations in Texas, Alabama, Georgia, and Flori ...
... Surveillance and monitoring are important for measuring the level of disease in a population, documenting changes in prevalence over time, determining high-risk areas for implementation of control measures, eradicating disease, and documenting freedom from disease. The documentation of freedom from disease has importance for international trade and the resumption of production after an outbreak. J ...
rivers; agricultural watersheds; land use; water quality; water pollution; USDA; conservation programs; governmental programs and projects; conservation practices; erosion control; Soil and Water Assessment Tool model; agricultural runoff; nutrient management; soil organic carbon; soil quality; Texas
Abstract:
... The Leon River basin was selected as a benchmark watershed for the Conservation Effects Assessment Project to complement the historical USDA Agricultural Research Service experimental watersheds near Riesel, Texas. Excessive nutrient and bacteria concentrations contributed by agricultural, urban, and natural sources are the primary water quality concerns. Modeling and field evaluations of the hydr ...
conservation areas; forest trees; botanical composition; forest management; wildlife habitats; floodplains; wild birds; lowland forests; stand basal area; vegetation structure; density; Gulf of Mexico region; Texas; Southeastern United States
Abstract:
... The Columbia Bottomlands, a Southern floodplain forest formation on the upper Texas coast, historically covered over 283,000 ha but has since been reduced to 25% of its former extent. The importance of this regional ecosystem as critical stopover and staging habitat for Nearctic-Neotropical migratory landbirds gave rise to the Columbia Bottomlands Conservation Plan, an active land acquisition and ...
Hispanics; auctions; clothing; corn; cotton; demographic statistics; markets; men; polylactic acid; production technology; regression analysis; willingness to pay; women; Texas
Abstract:
... This study of value-based labelling for apparel products examined consumer willingness to pay (WTP) for three credence attributes of fibre: origin, type and production method. Experimental auctions were conducted with student subjects in Texas and used socks made from cotton and polylactic acid (PLA), a fibre manufactured from corn. The bid results of two rounds were compared. The first round was ...
... Organic agriculture has been advanced as a production system that improves environmental quality and supports rural community development. Recent developments in organics have called into question both assertions. Researchers have argued that the advent of national-level organic standards has contributed to the conventionalization and bifurcation of organics. Conventionalization refers to the proc ...
soil water content; drainage; lawns and turf; watersheds; rain; watershed hydrology; turf grasses; runoff; golf courses; Texas; Minnesota
Abstract:
... Storm event runoff is a critical component to the environmental and structural design related to hydrology. The curve number (CN) method is a robust and accepted method for determining excess rainfall. Measured CNs for golf course watersheds, and for that matter hydrologic data from golf course watersheds, are limited. Rainfall-runoff data from two golf courses, Morris Williams Municipal Golf Cour ...
... Accumulation of dairy manure compost has created a need to identify alternative uses for this plant nutrient source. This field study determined compost effects on corn (Zea mays L.) silage production, nutritive value, and soil characteristics for three growing seasons following incorporation of dairy manure compost at 0, 35, 70, and 105 Mg dry matter (DM) ha⁻¹ Yields from subplots receiving annua ...
... Few native herbaceous perennial warm-season legumes are available for cultivation in the southern United States. Additional germplasm would be useful for pastures, biomass production, wildlife plantings, rangeland reseeding, or native prairie restoration. Three native perennial legumes were selected from an initial screening of north-central Texas germplasm for potential domestication based on suc ...
... Few native herbaceous perennial warm-season legumes are available for cultivation in the southern United States. These would be useful for pastures, biomass production, wildlife plantings, rangeland reseeding, or native prairie restoration. Three native perennial legumes were selected from an initial screening of north Texas germplasm for potential domestication based on successful establishment, ...