Experiments in short-term memory usually collect binary data and pool the results of several subjects. The observed pooled proportion of recall is then transformed by the angular transformation to stabilize the variance. In this paper the variance of the transformed proportion is derived and a simple test statistic is obtained to check the validity of the binomial model. Some numerical comparisons for selected poolings are made.

A digraph group is a group defined by non-empty presentation with the property that each relator is of the form $R(x, y)$, where x and y are distinct generators and $R(\cdot , \cdot )$ is determined by some fixed cyclically reduced word $R(a, b)$ that involves both a and b. Associated with each such presentation is a digraph whose vertices correspond to the generators and whose arcs correspond to the relators. In this article, we consider digraph groups for strong digraphs that are digon-free and triangle-free. We classify when the digraph group is finite and show that in these cases it is cyclic, giving its order. We apply this result to the Cayley digraph of the generalized quaternion group, to circulant digraphs, and to Cartesian and direct products of strong digraphs.

OBJECTIVES/GOALS: Antibiograms are used to guide empiric antibiotic selection. However, it is unclear if antibiotic profiles differ between symptomatic urinary tract infections (UTIs) and asymptomatic bacteriuria (ASB). We aimed to compare antibiotic susceptibility profiles of urinary E. coli isolates from patients with a symptomatic UTI to those with ASB. METHODS/STUDY POPULATION: We conducted a cohort study of 1,140 urinary E. coli isolates from unique patients that received care through Vanderbilt University Medical Center (VUMC) from Nov 2020 – Jun 2021. We included any patient that was seen at VUMC as an inpatient, outpatient or at the emergency department with ≥ 105 colony forming units/mL E. coli detected from a clinical urine specimen. Chart abstractions were performed to capture reported UTI symptoms and demographic information. Descriptive statistics were conducted to compare antibiotic susceptibility profiles (i.e., susceptible, intermediate, resistant) between symptomatic and ASB groups. The risk of detection of a multidrug-resistant organism (MDRO) (intermediate, or resistant to at least one antibiotic in three or more classes) was assessed between groups. RESULTS/ANTICIPATED RESULTS: Among 1,140, 1,018 (89%) and 122 (11%) were symptomatic and ASB, respectively. When comparing symptomatic and ASB, the median ages were 50 and 46. Groups had similar proportions of no indwelling catheter (94% v. 95%) and without diabetes (87% v. 88%). The collection setting between inpatient, emergency department, and outpatient were similar with most being outpatient (79% v. 83%). The proportion of patients who were pregnant, immuno compromised, or had a structural/functional urinary tract abnormality were higher in the symptomatic group. The proportion of isolates resistant and susceptible to tested antibiotics were similar between groups, with only ciprofloxacin showing slightly higher resistance among ASB (16% v. 25%). The risk of MDRO detection was similar between groups (RR: 0.858, 95% CI: 0.64, 1.15). DISCUSSION/SIGNIFICANCE: Antibiotic susceptibility comparison demonstrated similar profiles, which suggests antibiogram use as appropriate to guide ASB treatment. Results offer insight on whether traditional methods for assessing antibiotic susceptibility on population-levels could benefit from further refinement by patient-specific clinical parameters.

A subcommittee of the Hawaii Governor's Joint Task Force on Rat Lungworm Disease developed preliminary guidelines for the diagnosis and treatment of neuroangiostrongyliasis (NAS) in 2018 (Guidelines, 2018). This paper reviews the main points of those guidelines and provides updates in areas where our understanding of the disease has increased. The diagnosis of NAS is described, including confirmation of infection by real-time polymerase chain reaction (RTi-PCR) to detect parasite DNA in the central nervous system (CNS). The treatment literature is reviewed with recommendations for the use of corticosteroids and the anthelminthic drug albendazole. Long-term sequelae of NAS are discussed and recommendations for future research are proposed.

Application timing and environmental factors reportedly influence the efficacy of auxinic herbicides. In resistance-prone weed species such as Palmer amaranth (Amaranthus palmeri S. Watson), efficacy of auxinic herbicides recently adopted for use in resistant crops is of utmost importance to reduce selection pressure for herbicide-resistance traits. Growth chamber experiments were conducted comparing the interaction of different environmental effects with application time to determine the influence of these factors on visible phytotoxicity and hydrogen peroxide (H2O2) formation in A. palmeri. Temperature displayed a high degree of influence on 2,4-D and dicamba efficacy in general, with applications at the low-temperature treatment (31/20 C day/night) resulting in an increase in phytotoxicity compared with high-temperature treatments (41/30 C day/night). Application time across temperature treatments significantly affected 2,4-D–induced phytotoxicity, resulting in a ≥30% increase across rates with treatments at 4:00 PM compared with 8:00 AM. Temperature differential had a significant influence on dicamba efficacy based on visible phytotoxicity data, with a ≥46% increase with a high (37/20 C day/night) compared with a low differential (41/30 C day/night). Concentration of H2O2 in herbicide-treated plants was 34% higher under a high temperature differential compared with the low differential. Humidity treatments and application time interactions displayed undetected or inconsistent effects on visible phytotoxicity and H2O2 production. Overall, temperature-related influences seem to have the largest environmental effect on auxinic herbicides within conditions evaluated in this study. Leaf concentration of H2O2 appears to be generally correlated with phytotoxicity, providing a potentially useful tool in determining efficacy of auxinic herbicides in field settings.

Remembering is dynamically entangled in conversations. The communicative function of episodic memory can be epistemic, as suggested by Mahr & Csibra (M&C). However, remembering can have genuinely social functions, specifically, the creation or consolidation of interpersonal relationships. Autonoesis, a distinct feature of episodic memory, is more likely to have evolved in the service of social binding than of epistemic assertiveness.

The effects of formulation on clomazone volatilization and transport through soil were studied. After 22 days of leaching under unsaturated flow in 49-cm long intact soil cores, greater clomazone movement was observed in Plainfield sand than in Cisne silt loam or Drummer silty clay loam soils. Soil clomazone concentrations resulting in injury to oats occurred throughout Plainfield soil cores but were restricted to the upper 14 cm of Cisne and Drummer soils. In addition, clomazone was detected in the leachate from Plainfield soil only. In a similar study with Plainfield sand cores, clomazone was less mobile than atrazine; encapsulation of the herbicides in starch granules did not affect clomazone movement but greatly decreased atrazine movement from the soil surface. Similarly, starch encapsulation did not affect bioavailability of clomazone but did reduce bioavailability of atrazine. In a laboratory study with continual air flow, volatilization of clomazone applied to the soil surface was reduced by encapsulation in starch and starch/clay granules. Clomazone volatilization was not affected by soil water content within a range of 33 to 1500 kPa water tension. Following soil saturation with water, clomazone volatilization from both liquid and granular formulations increased. Granule size appeared to have a greater impact than granule composition on clomazone volatilization.

Earth's land-sea distribution modifies the temperature response to orbitally induced perturbations of the seasonal insolation. We examine this modification in the frequency domain by generating 800,000-yr time series of maximum summer temperature in selected regions with a linear, two-dimensional, seasonal energy balance climate model. Previous studies have demonstrated that this model has a sensitivity comparable to general circulation models for the seasonal temperature response to orbital forcing on land. Although the observed response in the geologic record is sometimes significantly different than modeled here (differences attributable to model limitations and feedbacks involving the ocean-atmosphere-cryosphere system), there are several results of significance: (1) in mid-latitude land areas the orbital signal is translated linearly into a large (>10°C) seasonal temperature response; (2) although the modeled seasonal response to orbital forcing on Antarctica is 6°C, the annual mean temperature effect (<2°C) is only about one-fifth that inferred from the Vostok ice core, and primarily restricted to periods near 41,000 yr; (3) equatorial regions have the richest spectrum of temperature response, with a 3000-yr phase shift in the precession response, plus some power near periods of 10,000–12,000 yr, 41,000 yr, 100,000 yr, and 400,000 yr. Peaks at 10,000–12,000 yr and 100,000 and 400,000 yr result from the twice-yearly passage of the sun across the equator. The complex model response in equatorial regions has some resemblance to geologic time series from this region. The amplification of model response over equatorial land masses at the 100,000-yr period may explain some of the observed large variance in this band in geologic records, especially in pre-Pleistocene records from times of little or no global ice volume.

Reduction of seed-bank persistence is an important goal for weed management systems. Recent interest in more biological-based weed management strategies has led to closer examination of the role of soil microorganisms. Incidences of seed decay with certain weed species occur in the laboratory; however, their persistence in soil indicates the presence of yet-unknown factors in natural systems that regulate biological mechanisms of seed antagonism by soil microorganisms. A fundamental understanding of interactions between seeds and microorganisms will have important implications for future weed management systems targeting seed banks. Laboratory studies demonstrate susceptibility to seed decay among weed species, ranging from high (velvetleaf) to very low (giant ragweed). Microscopic examinations revealed dense microbial assemblages formed whenever seeds were exposed to soil microorganisms, regardless of whether the outcome was decay. Microbial communities associated with seeds of four weed species (woolly cupgrass, jimsonweed, Pennsylvania smartweed, and velvetleaf) were distinct from one another. The influence of seeds on microbial growth is hypothesized to be due to nutritional and surface-attachment opportunities. Data from velvetleaf seeds suggests that diverse assemblages of bacteria can mediate decay, whereas fungal associations may be more limited and specific to weed species. Though microbial decay of seeds presents clear opportunities for weed biocontrol, limited success is met when introducing exogenous microorganisms to natural systems. Alternatively, a conservation approach that promotes the function of indigenous natural enemies through habitat or cultural management may be more promising. A comprehensive ecological understanding of the system is needed to identify methods that enhance the activities of microorganisms. Herein, we provide a synthesis of the relevant literature available on seed microbiology; we describe some of the major challenges and opportunities encountered when studying the in situ relationships between seeds and microorganisms, and present examples from studies by the ARS Invasive Weed Management Unit.

Ten years of Oregon Seed Certification Service (OSCS) preharvest field inspections converted from a nonspatial database to a geographic information system (GIS) were analyzed for patterns in spatial distribution of occurrence and severity of the 36 most common weeds of grass seed crops. This was done under the assumptions that those patterns would be primarily consequences of interactions among farming practices, soil properties, and biological traits of the weeds, and that improved understanding of the interactions would benefit the grass seed industry. Kriging, Ripley's K-function, and both Moran's I spatial autocorrelation and Getis-Ord General G high/low clustering using the multiple fixed distance band option all produced roughly similar classifications of weeds possessing strongest and weakest spatial clustering patterns. When Moran's I and General G analyses of maximum weed severity observed within individual fields over the life of stands were conducted using the inverse distance weighting option, however, results were highly sensitive to the presence of a small number of overlapping fields in the 10-yr record. Addition of any offset in the range from 6 to 6,437 m to measured distances between field centroids in inverse distance weighting matrices removed this sensitivity, and produced results closely matching those for the multiple fixed distance band method. Clustering was significant for maximum severity within fields over the 10-yr period for all 43 weeds and in 78% of single-year analyses. The remaining 22% of single-year cases showed random rather than dispersed distribution patterns. In decreasing order, weeds with strongest inverse-distance spatial autocorrelation were German velvetgrass, field bindweed, roughstalk bluegrass, annual bluegrass, orchardgrass, common velvetgrass, Italian ryegrass, Agrostis spp., and perennial ryegrass. Of these nine weeds, distance for peak spatial autocorrelation ranged from 2 km for Agrostis spp. to 34 km for common velvetgrass. Weeds with stronger spatial autocorrelation had greater range between distance of peak spatial autocorrelation and maximum range of significance. Z-scores for General G high/low clustering were substantially lower than corresponding values for Moran's I spatial autocorrelation, although the same two weeds (German velvetgrass and field bindweed) showed strongest clustering using both measures. Simultaneous patterns in Moran's I and General G implied that management practices relatively ineffective in controlling weeds usually played a greater role in causing weeds to cluster than highly effective practices, although both types of practices impacted Italian ryegrass distribution. Distance of peak high/low clustering among perennial weeds was smallest (1 to 3 km) for Canada thistle, field bindweed, Agrostis spp., and western wildcucumber, likely indicating that these weeds occurred in patchy infestations extending across neighboring fields. Although both wild carrot and field bindweed doubled in average severity over the period from 1994 to 2003, wild carrot was the only weed clearly undergoing an increase in spatial autocorrelation. Soil chemical and physical properties and dummy variables for soil type and crop explained small but significant portions of total variance in redundancy and canonical correspondence analysis of weed occurrence and severity. Fitch-Morgoliash tree diagrams and Redundancy Analysis (RDA) and Canonical Correspondence Analysis (CCA) ordinations revealed substantial differences among soil types in weed occurrence and severity. Gi∗ local hot-spot clustering combined with feature class to raster conversion protected grower expectations of confidentiality while describing dominant spatial features of weed distribution patterns in maps released to the public.

Obtaining radiocarbon assays on objects of chronological interest is always preferable to obtaining assays on spatially associated charcoal. The development of Accelerator Mass Spectrometer (AMS) dating has expanded the number of objects that can be directly assayed because it requires only a few milligrams of material. Pottery can be directly assayed when charred cooking residues adhering to the interior walls are present. The accuracy of AMS ages derived from residues has been questioned in cases where cooking freshwater aquatic organisms may have introduced carbon from ancient carbon reservoirs into residues. Here we provide analytic protocols for examination of this phenomenon and the results of systematic modeling of age estimates on residues formed from fish and maize with varying percentages of dead carbon. We present a regional case study using a large series of AMS age estimates on residues from the Finger Lakes region of northeastern United States to demonstrate how the paleolimnological record and lipid analysis of residues can help to determine if dates on residues from a given region are likely to have been affected by the presence of ancient carbon. In the case of the Finger Lakes, there is no evidence that ancient carbon affected the age estimates.