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Winter annual cover crops can be planted before soybean in Mississippi for many agronomic reasons. Incorporating winter annual cover crops into soybean production changes the seasonal hosts within fields. Some studies suggest that reducing tillage and using diverse species of cover crops can increase arthropod diversity and predator activity. Neonicotinoid seed treatments are often implemented to combat early season insect pests in soybean that follow cover crops, but negative effects on the environment such as reductions in biodiversity are often attributed to these compounds. We conducted an experiment to measure the effects on the diversity of the soybean epigeal and foliar communities when incorporating cover crops as well as insecticidal seed treatments into Mississippi soybean growing systems. Our results showed that legume cover crops had significant impacts on the epigeal community diversity of soybean planted behind them. These cover crops, especially hairy vetch, supported a more diverse foliar community before termination. To prevent increases in herbivorous arthropods, neonicotinoid seed treatments can be used without affecting epigeal predators such as beetles, ants, and spiders. The neonicotinoid seed treatments affected arthropod diversity, but the reductions were mainly caused by decreases in herbivorous pest insects that fed on treated soybean plants.

Mainstem girdling of soybean seedlings by threecornered alfalfa hoppers, Spissistilus festinus (Say), can result in several plant responses: (1) death of the plant, usually within 2 - 3 wks of injury,(2) mainstem breakage at the girdle soon after girdling through maturity, (3) partial breakage at the girdle with continued plant growth, (4) or the injured area (girdle) may heal over and the plant remain upright. Studies were conducted to simulate plant loss occurring during the reproductive growth stages which would result from threecornered alfalfa hopper injury during the early vegetative growth stages and examine the impact of this plant loss on yield of full-season indeterminate, late-planted/double-crop indeterminate, and full-season determinate soybeans, Glycine max (L.) Merr., at specific reproductive growth stages. Yield of full-season indeterminate soybeans was reduced by 6.4 - 15% when plant loss exceeded 20% at the R1–R2 growth stage. At R3 and R5, yields were reduced 7.4 - 30% and 7.2%...

The susceptibilities of 18 field populations of the sugarcane borer, Diatraea saccharalis (F.), to two sources of Bacillus thuringiensis (Bt) Cry1Ab protein were determined using laboratory bioassays. Fifteen of the 18 field populations were collected from seven locations across Louisiana and the other three populations were sampled from the Gulf Coast area of Texas during 2004–2006. Neonates of D. saccharalis were exposed to a meridic diet treated with selected concentrations of Cry1Ab protein. Larval mortality was measured at 7 days after inoculation. Statistically significant differences in median lethal concentrations (LC50s) were detected among insect populations from different geographical locations, but the field populations remained as susceptible as a laboratory strain of D. saccharalis that had been maintained in the laboratory for >20 years without exposure to any chemical insecticides or Bt toxins. The LC50s of Cry1Ab protein, which was extracted from DKC69-70 Bt corn hybrid, ranged from 0.03 to 0.32 μg/g for the seven field populations collected during 2004. The LC50 values based on bioassays with purified, trypsin-activated Cry1Ab protein from a recombinant Escherichia coli culture were 0.03–0.17 μg/g for the 11 field populations collected during 2005–2006. Small changes in Cry1Ab susceptibility were detected among crops, years of sampling, or locations. All field-collected insect populations, except one, exhibited lower LC50 values than the laboratory strain. The results of this study suggest that field populations of D. saccharalis remain generally susceptible to the Cry1Ab protein after 8 years use of transgenic Bt corn in Louisiana and the Gulf Coast area of Texas.

The eddy correlation (ECOR) flux measurement system provides in situ, half-hour measurements of the surface turbulent fluxes of momentum, sensible heat, latent heat, and carbon dioxide (CO2) (and methane at one Southern Great Plains extended facility (SGP EF) and the North Slope of Alaska Central Facility (NSA CF). The fluxes are obtained with the eddy covariance technique, which involves correlation of the vertical wind component with the horizontal wind component, the air temperature, the water vapor density, and the CO2 concentration. The instruments used are: • a fast-response, three-dimensional (3D) wind sensor (sonic anemometer) to obtain the orthogonal wind components and the speed of sound (SOS) (used to derive the air temperature) • an open-path infrared gas analyzer (IRGA) to obtain the water vapor density and the CO2 concentration, and • an open-path infrared gas analyzer (IRGA) to obtain methane density and methane flux at one SGP EF and at the NSA CF. The ECOR systems are deployed at the locations where other methods for surface flux measurements (e.g., energy balance Bowen ratio [EBBR] systems) are difficult to employ, primarily at the north edge of a field of crops. A Surface Energy Balance System (SEBS) has been installed collocated withmore » each deployed ECOR system in SGP, NSA, Tropical Western Pacific (TWP), ARM Mobile Facility 1 (AMF1), and ARM Mobile Facility 2 (AMF2). The surface energy balance system consists of upwelling and downwelling solar and infrared radiometers within one net radiometer, a wetness sensor, and soil measurements. The SEBS measurements allow the comparison of ECOR sensible and latent heat fluxes with the energy balance determined from the SEBS and provide information on wetting of the sensors for data quality purposes. The SEBS at one SGP and one NSA site also support upwelling and downwelling PAR measurements to qualify those two locations as Ameriflux sites.« less

Transgenic maize [Zea mays L. (Poaceae)] expressing Bacillus thuringiensis proteins (Bt maize) has become the most important tool for managing stalk borers in maize in the USA. The current strategy for delaying the evolution of resistance in target insects for Bt maize is referred to as high dose/ refuge strategy. A key requirement of the strategy is that initial resistance allele frequencies in field insect populations are low (e.g.

On 19 December 2008, a large portion of the S-shaped, steel-framed walkway under construction at the Atlanta Botanical Gardens suddenly collapsed during concrete placement operations. The approximately 575 ft long cable-stayed canopy bridge was designed to be supported by four masts along the curved spline segments and two opposing inclined columns at the transitional straight spline segments. At the time of collapse, the walkway structure was supported on temporary shoring tower frames and helical piles. A detailed study of movement and structural behavior was used to investigate the cause of collapse. Construction photos made it possible to compare erected locations of shoring tower frames and grillage members with their post-collapse locations and stacked configurations. Spline impact marks on the ground and shoring members below showed varying degrees of post-impact translation at points along the length of the collapsed walkway structure. Type and directionality of bolt failures at spline beam splices and abutments, and angles of inclination of shoring tower support piles above the ground surface were also considered. The movement displayed in these various elements pointed toward likely locations of collapse initiation among the numerous shoring towers. This study of movement allowed for a focused investigation to establish probable cause of the collapse.

Coapplication of herbicides and insecticides affords growers an opportunity to control multiple pests with one application given that efficacy is not compromised. Trifloxysulfuron was applied at 5.3 g ai/ha both alone and in combination with the insecticides acephate (370 g ai/ha), oxamyl (370 g ai/ha), lambda-cyhalothrin (34 g ai/ha), acetamiprid (45 g ai/ha), thiamethoxam (45 g ai/ha), endosulfan (379 g ai/ha), indoxacarb (123 g ai/ha), emamectin benzoate (11 g ai/ha), methoxyfenozide (67 g ai/ha), spinosad (75 g ai/ha), and pyridalyl (112 g ai/ha) to determine the effects of coapplication on control of some of the more common and/or troublesome broadleaf weeds infesting cotton. In addition, the insecticides acephate, oxamyl, lambda-cyhalothrin, thiamethoxam, and endosulfan, at the rates listed above, were applied either alone or in combination with trifloxysulfuron at 7.9 g/ha to assess the effects of coapplication on thrips control. Control of hemp sesbania (insecticides oxamyl and lambda-cyhalothrin), sicklepod (insecticides methoxyfenozide and pyridalyl), redroot pigweed (insecticides thiamethoxam, methoxyfenozide, spinosad, and pyridalyl), and smooth pigweed, Palmer amaranth, and common lambsquarters (all insecticides) with trifloxysulfuron may be reduced when coapplied with the indicated insecticides for each species. Control of pitted, tall, ivyleaf, and entireleaf morningglory with trifloxysulfuron was not affected by the insecticides evaluated. Coapplication of trifloxysulfuron with the insecticides evaluated also resulted in no negative effects on thrips control.

Beet armyworm, Spodoptera exigua (Hubner), and fall armyworm, Spodoptera frugiperda (J. E. Smith), are occasional pests of cotton, Gossypium hirsutum (L.), and soybean, Glycine max (L.) Merrill. These insects can be difficult to control due to insecticide resistance and larval behavior on plants. The objectives of these studies were to determine the efficacy of selected insecticides against native infestations of beet armyworm in cotton and soybean and to generate baseline dose-mortality responses for beet armyworm and fall armyworm adults to indoxacarb and pyridalyl in the adult vial test. Indoxacarb, pyridalyl, spinosad, methoxyfenozide, and emamectin benzoate controlled beet armyworm infestations up to 10 d after treatment compared to the non-treated control. Thiodicarb reduced beet armyworm densities up to three d after treatment. The LC50 values of indoxacarb and pyridalyl for beet armyworm and fall armyworm exceeded the highest concentrations tested (100-200 μg/vial) in the adult vial test. Dose-mortality values of indoxacarb and pyridalyl were higher than discriminating concentrations of cypermethrin, methomyl, profenofos, and endosulfan used in the adult vial test for monitoring tobacco budworm, Heliothis virescens (F.), and bollworm, Helicoverpa zea (Boddie), susceptibility in Louisiana and Texas. These results indicate that the adult vial test may not be the most efficient test method for indoxacarb and pyridalyl in insecticide susceptibility monitoring programs.

In each of two experiments, 924 pigs (4.99 kg BW; 16 to 18 d of age) were assigned to 1 of 42 pens based on BW and gender. Pens were allotted randomly to dietary copper (Cu) treatments that consisted of control (10 ppm Cu as cupric sulfate, CuSO4 x 5H2O) and supplemental dietary Cu concentrations of 15, 31, 62, or 125 ppm as cupric citrate (CuCit), or 62 (Exp. 2 only), 125 (Exp. 1 only), or 250 ppm as CuSO4. Live animal performance was determined at the end of the 45-d nursery phase in each experiment. On d 40 of Exp. 2, blood and fecal samples were collected from two randomly selected pigs per pen for evaluation of plasma and fecal Cu concentrations and fecal odor characteristics. In Exp. 1, ADG, ADFI, and G:F were increased (P < 0.05), relative to controls, when pigs were fed diets containing 250 ppm Cu as CuSO4. Pigs fed diets containing 125 ppm Cu as CuCit had increased (P < 0.05) ADG compared with pigs fed diets supplemented with 15 or 62 ppm Cu as CuCit. The ADG, ADFI, and G:F did not differ among pigs fed diets containing 125 and 250 ppm Cu as CuSO4 or 125 ppm Cu as CuCit. In Exp. 2, pigs fed diets containing 250 ppm Cu as CuSO4 had improved (P < 0.05) ADG, ADFI, and G:F compared with controls. In addition, ADG, ADFI, and G:F were similar when pigs were fed diets containing either 250 ppm Cu as CuSO4 or 125 ppm Cu as CuCit. Pigs fed diets containing 62 ppm Cu as CuSO4 or CuCit had similar ADG, ADFI, and G:F. Plasma Cu concentrations were not affected by dietary Cu source or concentration, but fecal Cu concentrations were increased (P < 0.05) as the dietary concentration of Cu increased. Pigs consuming diets supplemented with 125 ppm Cu as CuCit had fecal Cu concentrations that were lower (P < 0.05) than pigs consuming diets supplemented with 250 ppm Cu as CuSO4. Fecal Cu did not differ in pigs receiving diets supplemented with 62 ppm Cu as CuSO4 or CuCit. Odor characteristics of feces were not affected by Cu supplementation or source. These data indicate that 125 and 250 ppm Cu gave similar responses in growth, and that CuCit and CuSO4 were equally effective at stimulating growth and improving G:F in weanling pigs. Fecal Cu excretion was decreased when 125 ppm Cu as CuCit was fed compared with 250 ppm Cu as CuSO4. Therefore, 125 ppm of dietary Cu, regardless of source, may provide an effective environmental alternative to 250 ppm Cu as CuSO4 in weanling pigs.

The common species of thrips that are considered pests of cotton, Gossypium hirsutum (L.), include flower thrips, Frankliniella tritici (Fitch); tobacco thrips, Frankliniella fusca (Hinds); western flower thrips, Frankliniella occidentalis (Pergande); onion thrips, Thrips tabaci (Lindeman); and soybean thrips, Neohydatothrips variabilis (Beach). Thrips feeding on cotton seedlings can inhibit plant growth, reduce plant stand, delay crop maturity, and reduce seed-cotton yield. Surveys were conducted in Alabama, Arkansas, Georgia, Louisiana, Mississippi, and Tennessee to determine the thrips species infesting cotton seedlings during 1996 to 1999. Cotton seedlings were sampled weekly between 7 and 48 days after plant emergence at one to four field sites in each state. Over 12,000 thrips adults were collected using plant washing procedures with 9,005 individuals mounted on slides, and identified to species. The tobacco thrips was the most common species collected in all states, except Georgia, and comprised at least 63% of the thrips adults in all instances, except four. The occurrence of flower thrips and soybean thrips was variable; however, neither species accounted for more than 21% of thrips identified in each state. Western flower thrips accounted for less than 15% of adults collected in all instances except two (28% and 30%) in Louisiana. Also, individual specimens of Thrips nigropilosus Uzel and Anophothrips obscurus Müller were collected in Alabama, and several specimens of Microcephalothrips abdominalis (Crawford) were collected in Arkansas and Louisiana.

A large spark generator was used outdoors to determine the production of nitrogen oxides (NOx) from sparks with characteristics similar to those of lightning strokes. The experiment was conducted at the Rocket Triggered Lightning Program facility at Cape Canaveral, Florida, in August 1991, during the Convection and Precipitation/Electrification field experiment. Plumes of NOx from spark generations were sensed by a NOx analyzer. The spark energy was 9.8±0.7×104 J, and the spark gap was 1.65 or 2.13 m. The plumes reached the analyzer inlet within 0.3–4.7 s after spark generation. The NOx concentrations varied, depending on the geometry of the plume. Laboratory studies of analyzer response permitted adjustment of the measured concentrations to corrected concentrations. Production of NOx, in terms of mass of nitrogen, averaged 22.5±2.9 mg per spark, 11.7±1.5 mg m−1 of spark length, and 1.1±0.2×1016 molecules J−1. The median ratio of nitric oxide (NO) to nitrogen dioxide (NO2) was 0.76, indicating substantial conversion within a few seconds. Scaling of NOx production to lightning energy levels and dimensions yielded an annual global NOx production of 9.7 Tg yr−1, similar to values estimated from recent thunderstorm measurements and modeling studies. Recent satellite measurements suggest that cloud-to ground lightning flash frequency is an order of magnitude smaller than normally assumed; estimates of global NOx production by lightning might also need to be reduced by an order of magnitude.

Retrospektive Studien lieferten Hinweise, dass Bluttransfusionen vermutlich noch nach vielen Jahren die Immunfunktion beeinflussen und mit einem erhohten Risiko fur Infektionen, maligne Erkrankungen und ggf. erhohter Mortalitat assoziiert sein konnten. Andererseits reduziert ein liberales Transfusionsregime insbesondere bei Risikopatienten postoperativ die kardialen Komplikationen.

Cisatracurium, one of 10 isomers of atracurium, undergoes pH and temperature-dependent Hofmann elimination in plasma and tissues. The clearance of cisatracurium due to Hofmann elimination and organ elimination was estimated by applying a nontraditional two-compartment pharmacokinetic model with elimination occurring from both compartments to plasma cisatracurium concentration-time data from 31 healthy adult surgical patients with normal renal and hepatic function. The elimination rate constant from the central compartment, intercompartmental rate constants, and the volume of the central compartment were obtained from the model fit. The elimination rate constant from the peripheral compartment could not be independently estimated in vivo and was therefore fixed to the rate of degradation of cisatracurium in human plasma (pH 7.4 and 37 degrees C) and held constant in the model. Total body clearance, Hofmann clearance, organ clearance, and the volume of distribution at steady-state were derived from the model parameter estimates. Renal clearance was calculated from cisatracurium urinary excretion data from 12 of the 31 patients. Clearance values (mean +/- SD) were 5.20 +/- 0.86, 4.00 +/- 1.04, 1.20 +/- 0.71, and 0.85 +/- 0.32 mL.min-1.kg-1 for total body clearance, Hofmann clearance, organ clearance, and renal clearance, respectively. Hofmann clearance accounted for 77% of total body clearance. Organ clearance was 23% of total body clearance. Renal clearance, a component of organ clearance, was 16% of total body clearance. The organ-independent nature of the elimination of cisatracurium was characterized by a relationship between steady-state volume of distribution and total body clearance. The half-life is an independent variable and is not dependent on the total body clearance nor the steady-state volume of distribution. Hofmann elimination is the predominant pathway for cisatracurium elimination in humans.

Corrections and improvements have been made to published equations relating return stroke peak current and peak electric field for cloud-to-ground lightning. The original equations were derived from measurements made at the Rocket-Triggered-Lightning Program facility at the Kennedy Space Center in Florida. Some previous articles include errors in the conversion of equations from units of volts per meter, for peak electric field, into Lightning Location and Protection units, representing normalized signal strength amplitude. This article presents the proper conversion procedure and the resultant corrected equations. Furthermore, equations are presented that were produced by converting other published relationships. Finally, we combined 1985--1988 RTLP data to produce equations based on more data than has been used previously; the resulting equation for peak current as a function of normalized signal strength amplitude supports previous evidence that the slope should be near 0.2 for a zero intercept. All relationships are tabulated, and three are graphically compared against the data.

We compared both the time course of neuromuscular blockade and the cardiovascular side-effects of suxamethonium and mivacurium during halothane and nitrous oxide anaesthesia in infants 2-12 months and children 1-12 years of age. Equipotent doses of mivacurium and suxamethonium were studied; 2.2 x ED95 was used in four groups of infants and children, while 3.4 x ED95 was used in two groups of children. Onset of neuromuscular block in infants was not significantly faster with suxamethonium than with mivacurium (P = 0.2). In all infants given suxamethonium, intubating conditions were excellent, while, in 6/10 infants given mivacurium, intubating conditions were excellent. Onset of complete neuromuscular block in children was significantly faster with suxamethonium, 0.9 min compared with mivacurium, 1.4 min (P < or = 0.05). Increasing the dose of suxamethonium or mivacurium in children to 3.4 x ED95 did not change the onset of neuromuscular block. Recovery of neuromuscular transmission to 25% of initial twitch height (T25) in infants and children was significantly faster after suxamethonium than after mivacurium, at 2.5 and 6 min, respectively (P < or = 0.05). In children given 3.4 x ED95 of suxamethonium or mivacurium, recovery from neuromuscular block was almost identical with the dose of 2.2 x ED95, with spontaneous recovery to T25 prolonged by only 0.5 min. No infant or child had hypotension after the mivacurium bolus dose.

The efficacy of selected insecticides against bean leaf beetle was evaluated at the Delta Research and Extension Center (Washington County). Soybean seed (Asgrow 4831) were planted on a Tunica clay soil on 11 Jun. Plot size was four rows (40-inch centers) by 50 ft. Treatments were replicated …

Aspiration pneumonitis is a severe complication of anesthesia. The objectives of this study were to determine if preoperative famotidine, a new histamine2-receptor antagonist, given by mouth either the evening before or the morning of elective surgery, reduced gastric residual volume and increased gastric pH in pediatric patients. Either famotidine or placebo (or both) were orally administered to 58 children (aged 2-17 years). The patients were randomly assigned to four groups: Famotidine-Famotidine, Placebo-Placebo, Placebo-Famotidine, and Famotidine-Placebo; subjects in the Famotidine-Famotidine group received two doses of famotidine (0.5 mg.kg-1 per dose), those in the Placebo-Placebo group, two doses of placebo, those in the Placebo-Famotidine and Famotidine-Placebo group, one dose of each by mouth. The Famotidine-Famotidine group received one dose of famotidine at 22:00 the evening before surgery and a second dose 60-90 min before the scheduled time of surgery. The Placebo-Placebo group received two doses of placebo at the same times as the Famotidine-Famotidine group. The Placebo-Famotidine group received a dose of placebo the night before surgery and a dose of famotidine the morning of surgery; the Famotidine-Placebo group received famotidine the night before surgery and placebo the morning of surgery. The administration of famotidine on the morning of surgery significantly increased gastric pH (4.8 vs. 1.3) in comparison with placebo, as did two doses of famotidine (6.6). Famotidine failed to reduce gastric residual volume significantly in any group. The administration of famotidine significantly reduced the number of pediatric patients considered at higher risk for aspiration pneumonitis, despite not decreasing gastric residual volume.

The impact of selected at-planting insecticides treatments on soybean yield was evaluated at the Delta Research and Extension Center (Washington County). Soybean seed (Asgrow 4934) were planted on a Commerce silty clay loam soil on 22 Apr at a seeding rate of 117,612 seed/acre. Plant emergence date was 1 May. Plot size was four rows (40 in. centers) by 40 ft. Treatments were replicated four times in an RCB. All seed used in the trial received a commercial fungicide seed treatment. The Gaucho treatment was applied as a seed treatment at the commercial rate of …

The efficacy of selected insecticides against Dectes stem borer was evaluated at the Delta Research and Extension Center (Washington County) in two trials. In Trial 1, soybean seed (Asgrow 4632) were planted on a Beulah very fine sandy loam soil on 6 May. In Trial 2, soybean seed (Asgrow 4831) were planted on a Commerce silty clay loam soil on 13 May. Plot size was four rows …

Cottonseed were planted on a Commerce silt loam soil on 20 Jun. Plot size was four rows (centered on 40 inches) by 50 ft. Treatments were replicated four times in a RCB. Treatments were applied on 18 Aug with a high clearance sprayer and CO2 charged spray system calibrated to deliver 6 gpa through Teejet TX-8 hollow cone nozzles (2 per row). Treatment efficacy was determined by sampling the center two rows of each plot with a sweep net (25 sweeps/row) at 5 and 7 DAT. Data for each row were averaged and all data were subjected to ANOVA and means separated according to Fisher’s Protected LSD (P = 0.05). No rainfall occurred from the application date until the end of sampling. Plots were mechanically harvested using a spindle type harvester on 26 Oct. Yields were converted to lb seed cotton/acre.

'Delta Pine 555 BR' cotton seed were planted on a Commerce silt loam soil on 19 Apr with a John Deere 7100 series planter equipped with 10-inch seed cones mounted to replace the seed hoppers. Plot size was four rows (40-inch centers) by 50 ft. Treatments were replicated four times in a RCB design. All seed treatments were applied by Syngenta. Granular in-furrow treatments (Temik 15G) were applied with 8-inch belt cone applicators mounted to replace the standard granular applicators. Control of thrips adults, thrips larvae, and aphids was determined by randomly selecting five plants per plot at 10, 13, 17, 21, 24, and 28 d after emergence (DAE). Whole plant washing procedures were used to remove the insects and counts were made with the aid of a dissecting microscope. Plant density was determined by counting all plants on the center two rows of each plot at 38 DAE. Plant height was determined by measuring 10 randomly selected plants from the center two rows of each plot at 38 DAE. Plots were mechanically harvested using a spindle type harvester on 19 Sep. Yields were converted to lb seed cotton/acre. Data were subjected to ANOVA and means were separated using an F protected LSD (P = 0.05).