Invasive emergent and floating macrophytes can have detrimental impacts on aquatic ecosystems. Management of these aquatic weeds frequently relies upon foliar application of aquatic herbicides. However, there is inherent variability of overspray (herbicide loss) for foliar applications into waters within and adjacent to the targeted treatment area. The spray retention (tracer dye captured) of four invasive broadleaf emergent species (water hyacinth, alligatorweed, creeping water primrose, and parrotfeather) and two emergent grass-like weeds (cattail and torpedograss) were evaluated. For all species, spray retention was simulated using foliar applications of rhodamine WT (RWT) dye as a herbicide surrogate under controlled mesocosm conditions. Spray retention of the broadleaf species was first evaluated using a CO2-pressurized spray chamber overtop dense vegetation growth or no plants (positive control) at a greenhouse (GH) scale. Broadleaf species and grass-like species were then evaluated in larger outdoor mesocosms (OM). These applications were made using a CO2-pressurized backpack sprayer. Evaluation metrics included species-wise canopy cover and height influence on in-water RWT concentration using image analysis and modeling techniques. Results indicated spray retention was greatest for water hyacinth (GH, 64.7 ± 7.4; OM, 76.1 ± 3.8). Spray retention values were similar among the three sprawling marginal species alligatorweed (GH, 37.5 ± 4.5; OM, 42 ± 5.7), creeping water primrose (GH, 54.9 ± 7.2; OM, 52.7 ± 5.7), and parrotfeather (GH, 48.2 ± 2.3; OM, 47.2 ± 3.5). Canopy cover and height were strongly correlated with spray retention for broadleaf species and less strongly correlated for grass-like species. Although torpedograss and cattail were similar in percent foliar coverage, they differed in percent spray retention (OM, 8.5± 2.3 and 28.9 ±4.1, respectively). The upright leaf architecture of the grass-like species likely influenced the lower spray retention values in comparison to the broadleaf species.

The Battelle Critical Care Decontamination System™ (CCDS™) decontaminates N95 filtering facepiece respirators (FFRs) using vapor phase hydrogen peroxide (VPHP) for reuse when there is a critical supply shortage. The Battelle CCDS received an Emergency Use Authorization (EUA) from the US Food and Drug Administration (FDA) in March 2020. This research focused on evaluating the mechanical properties of the straps as an indicator of respirator fit. The objective was to characterize the load generated by the straps following up to 20 don/doff and decontamination cycles in Battelle's CCDS. In general, the measured loads at 50 and 100% strains after 20 cycles were similar (±15%) to the as-received controls. Qualitatively, reductions in the load may be associated with loss of elasticity in the straps, potentially reducing the ability to obtain a proper fit. However, small changes in strap elasticity may not affect the ability to obtain a proper fit given the potential for variation in strap length and positioning on the head. Regardless, prior to reusing a N95 respirator, it is important to complete a visual inspection to ensure it is not damaged, malformed, or soiled. If so, it is recommended to discard the respirator and use a different one. Similarly, the respirator should be discarded if the wearer cannot obtain a proper fit during the user seal check.

The stellar winds of hot stars have an important impact on both stellar and galactic evolution, yet their structure and internal processes are not fully understood in detail. One of the best nearby laboratories for studying such massive stellar winds is the O4I(n)fp star ζ Pup. After briefly discussing existing X-ray observations from Chandra and XMM, we present a simulation of X-ray emission line profile measurements for the upcoming 840 kilosecond Chandra HETGS observation. This simulation indicates that the increased S/N of this new observation will allow several major steps forward in the understanding of massive stellar winds. By measuring X-ray emission line strengths and profiles, we should be able to differentiate between various stellar wind models and map the entire wind structure in temperature and density. This legacy X-ray spectrum of ζ Pup will be a useful benchmark for future X-ray missions.

Background: EMBRACE (NCT02462759) Part 1 is a randomized, double-blind, sham-procedure controlled study assessing safety/tolerability of intrathecal nusinersen (12-mg equivalent dose) in symptomatic infants/children with SMA who were not eligible to participate in ENDEAR or CHERISH. Methods: Eligible participants had onset of SMA symptoms at ≤6 months with 3 SMN2 copies; onset at ≤6 months, age >7 months and 2 copies; or onset at >6 months, age ≤18 months, and 2/3 copies. Safety/tolerability was the primary endpoint. Exploratory endpoints included Hammersmith Infant Neurological Examination Section 2 (HINE-2) motor milestone attainment, change in ventilator use, and growth. Results: EMBRACE Part 1 was terminated early based on positive results from ENDEAR. Safety/tolerability was similar to previous trials. More nusinersen-treated (11/14;79%) vs. sham–treated individuals (2/7;29%) were HINE-2 motor milestone responders. Between Day 183 and 302, mean (SD) hours of ventilator use changed by +1.236 (3.712) hours in nusinersen-treated (n=12) and +2.123 (3.023) hours in sham–treated individuals (n=7). Similar increases in weight and body length were observed in nusinersen-treated and sham–treated individuals by Day 183. Conclusions: In EMBRACE Part 1, nusinersen demonstrated a favorable benefit-risk profile. These results add to the aggregated efficacy, safety/tolerability data of nusinersen in SMA.

Study Supported by: Ionis and Biogen

Research has shown both production and health benefits for the use of chicory (Cichorium intybus) within ruminant diets. Despite this, little was known about the effects of this forage, containing differing fatty acid profiles and secondary plant compounds compared with ryegrass, on beef stability, fatty acid composition or sensory properties. An experiment was conducted to investigate whether the inclusion of chicory in the diet of grazing beef steers would alter these three properties in the M. Longissimus muscle when compared with beef steers grazing perennial ryegrass (Lolium perenne). Triplicate 2 ha plots were established with a chicory (cv. Puna II)/perennial ryegrass mix or a perennial ryegrass control. A core group of 36 Belgian Blue – cross steers were used within a 2-year beef finishing experiment (n=6/replicate plot). In the 2nd grazing year, steers were slaughtered as they reached a target fat class of 3. Muscle pH was checked 2 and 48 h post-slaughter. A section of the hindloin joint containing the M. Longissimus lumborum muscle was removed and a 20 mm-thick steak was cut and muscle samples were taken for analysis of vitamin E and fatty acid analysis. The remaining section of the loin was vacuum packed in modified atmosphere packs and subjected to simulated retail display. A section of the conditioned loin was used for sensory analysis. Data on pH, vitamin E concentration and colour stability in a simulated retail display showed there were no effects of including chicory in the diet of grazing beef steers on meat stability. There were also no differences found in the fatty acid composition or the overall eating quality of the steaks from the two treatments. In conclusion, there were no substantive effects of including chicory in the swards of grazing beef cattle on meat stability, fatty acid composition or sensory properties of the M. Longissimus muscle when compared with beef steers grazing ryegrass-only swards.

Woody plant encroachment restricts forage production and capacity to produce grazing livestock. Biophysical plant growth simulation and economic simulation were used to evaluate a prescribed burning range management technique. Modeling systems incorporated management practices and costs, historical climate data, vegetation and soil inventories, livestock production data, and historical regional livestock prices. The process compared baseline non-treatment return estimates to expected change in livestock returns resulting from prescribed burning. Stochastic analyses of production and price variability produced estimates of greater net returns resulting from use of prescribed burning relative to the baseline.

Predicted crop yields and wind erosion rates from a multi-year/multi-crop growth simulation model provided input into a multi-period recursive QP model to evaluate erosion implications during the transition to dryland crop production on the Texas Southern High Plains. Three farm-program participation options were considered in this study. Participation in an extension of the current farm program resulted in an increase in net returns and wind erosion rates above nonparticipation. Imposition of a soil loss limit without consideration of a flexible base option can significantly reduce discounted present values. Increasing risk aversion across producers affects crop mix selection which can result in lower per acre wind erosion rates for this particular region.

In anticipation of Congressional debates over an expanded environmental title in the 1990 farm bill, several studies on pesticide use and the impacts of reduction were undertaken (e.g., Smith et al., Knutson et al., Osteen and Szmedra, and GRC Economics). Osteen and Szmedra reported that the use of herbicides, insecticides, and fungicides increased steadily from post-World War II to 1982 before decreasing as crop prices declined and acreage reduction programs reduced planted acreage. Heightened concerns and perceptions about the presence of pesticides and nitrates in our food and water supplies have led to calls for the reduction and/or elimination of agricultural chemicals. For example, a National Academy of Science study has concluded and therefore fostered the perception that substantial reductions in chemical use are possible without large impacts on production and/or prices.

A general description of ablation polygons is given and variations from widely distributed regions are examined. After discussion of the conditions in which they most frequently develop, possible explanations are considered, leading to the conclusion that the polygons result from ablation by turbulence in the surrounding air, and that the dirt fringes to the polygons may be explained by the “normal trajectory” theory.

The synthetic auxin herbicides, aminocyclopyrachlor and clopyralid, control dicotyledonous weeds in turf. Clippings of turfgrass treated with synthetic auxin herbicides have injured off-target plants exposed to herbicide-laden clippings. Labels of aminocyclopyrachlor and clopyralid recommend that clippings of treated turfgrass remain on the turf following a mowing event. Alternative uses for synthetic auxin-treated turfgrass clippings are needed because large quantities of clippings on the turf surface interfere with the functionality and aesthetics of golf courses, athletic fields, and residential turf. A white clover bioassay was conducted to determine the persistence and bioavailability of aminocyclopyrachlor and clopyralid in turfgrass clippings. Aminocyclopyrachlor and clopyralid were each applied at 79 g ae ha−1 to mature tall fescue at 56, 28, 14, 7, 3.5, and 1.75 d before clipping collection (DBCC). Clippings were collected, and the treated clippings were recycled onto adjacent white clover plots to determine herbicidal persistence and potential for additional weed control. Clippings of tall fescue treated with aminocyclopyrachlor produced a nonlinear regression pattern of response on white clover. Calculated values for 50% response (GR50) for visual control, for normalized difference vegetative index (NDVI), and for reduction in harvested biomass were 20.5, 17.3, and 18.7 DBCC, respectively, 8 wk after clippings were applied. Clippings of tall fescue treated with clopyralid did not demonstrate a significant pattern for white clover control, presumably because clopyralid was applied at a less-than-label rate. The persistence and bioavailability of synthetic auxin herbicides in clippings harvested from previously treated turfgrass creates the opportunity to recycle clippings for additional weed control.

The General Accounting Office (GAO) recommended that the USDA substantially reduce or eliminate the extent of price discrimination practiced under federal milk marketing orders. The purpose of this study was to quantify the impacts of alternative means of implementing the GAO proposal on the economic viability of Texas and New Mexico dairy farms. Five dairy farms were simulated for six years under the current dairy policy and five alternative proposals. Results of the analyses indicate that large New Mexico dairies can remain economically viable under all of the alternatives. On the other hand, federal order policy changes would accelerate the loss of equity for moderate size Texas dairy farms.

Agricultural pesticide use has come under an intensive attack from an environmentally aware society. The Environmental Protection Agency has placed restrictions on use of selected pesticides, including DDT. The use of pesticide is a paradox in itself. Without feasible alternative insecticide strategies, such as biological control, restrictions on the use of pesticides will decrease agricultural output and food costs will increase. However, with pesticide use, social costs in the form of environmental damages may occur. To make an equitable decision as to the future of pesticides, researchers and policy-makers have tried to determine the optimal level of use, optimal timing of application, extent of economic benefits, extent of social costs, and the effects on the economy of pesticide restrictions.

This paper investigates the farm-level impacts of the 1996 farm bill on the South. Focus group perceptions of risk sources, observed acreage changes, and the farm-level impact of increased price risk are evaluated. Focus group respondents ranked price and yield as the two most important sources of risk, and diversification was ranked highly as a risk-management tool. Limited data suggest that acreage shifts among crops are occurring in the South, presumably aided by the 1996 farm bill. Higher probabilities of cash flow deficits are estimated for cotton and rice relative to feedgrain, wheat, and oilseed operations.

Domestic products have a disproportionately high market share on many goods markets. We examine the contribution of preferences to such “home bias”, using detailed data on wine sales in New Hampshire (weekly sales by brand by store for one year). In counterfactual simulations, where we use the same set of products as currently available, the U.S. market share falls from 58 percent to 38 percent if all country-of-origin effects are set equal. Home bias on this market is not explained by higher marginal costs for imports or by lesser store coverage of imported brands. The evidence rather points to higher foreign fixed costs of entry, coupled with a preference for U.S. wines, as the main sources for the high domestic market share. (JEL Classification: F12, F14, L13, L66)

The mean post-mating age of mated female moths of the European corn borer, Ostrinia nubilalis (Hübner), from light traps varied from 3.4 to 5.2 days during the June–September flight period at Harrow, Ontario, in a manner consistent with assignment of moths to 3 generations per year. At the beginning of the first generation the mean age was 3.66 days and rose to 5.21 before flights ceased. At the beginning of the second generation the mean age was 3.39 days and rose to 4.47 days. A third generation could be detected in early September by a significant drop in age and an increase in virgin females. The average age of mated females was negatively correlated with the proportion of virgin females in the same week (r = −0.648, P = 0.02), indicating that about 40% of the variance in age of mated females was associated with emergence of new recruits to the population. Females collected with a sweep net from their day time resting places in weeds were either the same age or older than those from the light trap. The mean age of moths from light traps was found to be not meaningful when it was tested as a factor in forecasting damage caused by their progeny in green peppers 3–5 weeks later.

Introduction of pneumococcal polysaccharide (PPV23) and conjugate vaccine (PCV7) programmes were expected to change the epidemiology of invasive pneumococcal disease (IPD) and pneumonia in the UK. We describe the epidemiology of IPD and hospitalization with pneumonia using high-quality surveillance data over an 8-year period, 2002–2009. Although PPV23 uptake increased from 49% to 70% and PCV7 uptake reached 98% by 2009, the overall incidence of IPD increased from 11·8/100 000 to 16·4/100 000 (P=0·13), and the incidence of hospitalization with pneumonia increased from 143/100 000 to 207/100 000 (P<0·001). Although a reduction in the proportion of IPD caused by PCV7 serotypes was observed, concurrent increases in PPV23 and non-vaccine serotype IPD contributed to an increased IPD burden overall. Marked inequalities in the geographical distribution of disease were observed. Existing vaccination programmes have, so far, not been sufficient to address an increasing burden of pneumococcal disease in our locality.

Puberty is defined in the Oxford English Dictionary as the state or condition of having become functionally capable of procreating offspring, suggesting that it is a discrete event that occurs at a particular point in time. Whilst it is easy to determine the age at puberty in animals from the time of completion of spermatogenesis in the male, or the first ovulation in the female, these are particularly difficult criteria to evaluate in our own species. Thus human puberty is generally described in terms of a sequence of changes in secondary sexual characteristics occurring over an extended period of time, and these have been reviewed in detail by Marshall & Tanner (1974).