Long strings of consecutive composite values of polynomials

We show that for any polynomial $f$ from the integers to the integers, with positive leading coefficient and irreducible over the rationals, if $x$ is large enough then there is a string of $(\log x)(\log\log x)^{1/835}$ consecutive integers $n \in [1,x]$ for which $f(n)$ is composite. This improves a result of the first author, Konyagin, Maynard, Pomerance and Tao, which states that there are such strings of length $(\log x)(\log\log x)^{c_f}$, where $c_f$ depends on $f$ and $c_f$ is exponentially small in the degree of $f$ for some polynomials.Comment: 22 page

Sets whose differences avoid squares modulo m

We prove that if $\varepsilon(m)\to 0$ arbitrarily slowly, then for almost all $m$ and any $A\subset\mathbb{Z}_m$ such that $A-A$ does not contain non-zero quadratic residues we have $|A|\leq m^{1/2-\varepsilon(m)}.$Comment: 14 page

Physical Condition, Sex, and Age-Class of Eastern Red-Backed Salamanders ( Plethodon cinereus

Nonforested habitats such as open fields and pastures have been considered unsuitable for desiccation-prone woodland salamanders such as the Eastern Red-backed Salamander (Plethodon cinereus). Recent research has suggested that Plethodon cinereus may not only disperse across but also reside within open habitats including fields, meadows, and pastures. However, presence and high densities of P. cinereus within agriculturally disturbed habitats may be misleading if these populations exhibit atypical demographic characteristics or decreased physical condition relative to forest populations. We surveyed artificial cover boards from 2004-2005 to compare physical condition, sex ratios, and age-class structure of P. cinereus among woodland, woodland-meadow edge, silvopasture, and meadow sites in the central Appalachian Mountains of southern West Virginia. Physical condition of salamanders was not significantly different among the four habitats. Furthermore, adult sex ratios of P. cinereus typically were not significantly different from 1 : 1 and were similar between forested and non-forested sites, although populations within silvopastures were biased towards females. However, adult salamanders were significantly more abundant than juveniles in all habitat types, with differences most pronounced within meadow habitats. Our study indicates that relatively small, non-forested habitats such as silvopastures and meadows may not adversely affect the overall physical condition or sex ratios of Plethodon cinereus. However, the paucity of juveniles within disturbed meadows indicates that these agriculturally modified habitats may negatively impact reproduction or that immature salamanders are at a physiological or competitive disadvantage in comparison to adults, particularly when surface cover is limited

Exploring standardized persons\u27 expectations for practice-readiness among student pharmacists

Although patient expectations and preferences for healthcare selection have been described in the literature, there are no studies exploring what qualities and behaviors standardized persons (SPs) identify for the practice-ready pharmacist. This manuscript explores those qualities and behaviors within an objective structured clinical examination (OSCE) to determine SP interest in having the student as their pharmacy provider. Methods: Using open-ended questions via a Qualtrics survey, SPs were asked to provide qualities and behaviors they associated with each of three practice-readiness rating levels. Using a constant comparative approach, the researchers coded the collected data over multiple stages to allow for authentic reflection and interpretation of the data. Coders used both inductive and deductive processes prior to establishing a unified understanding and corresponding codebook. Results: A total of 55 SPs (61.1% response rate) participated in the survey, with the majority of participants working for the organization no more than two years (58.2%). Through the coding process, several major themes emerged across each of the three ratings including professionalism, patient-centered skills, communication, and preparation. Findings indicated the differences in ratings were influenced by the degree that students demonstrated each theme. Conclusions: Overall, these findings provide a better understanding of the qualities and behaviors SPs associate with student pharmacists completing OSCEs acting as practicing pharmacists. However, additional research is needed to determine if the same qualities and behaviors would be viewed as essential with SPs at other academic institutions

Drivers of Macroinvertebrate Community Integrity Within Mixed Urban and Agricultural Dominated Mississippi Tributary Watersheds

The “urban stream syndrome” refers to a multitude of impacts caused by urbanization including flashier hydrograph, elevated concentrations of nutrients and contaminants, altered channel morphology and stability, reduced biotic richness, with increased dominance of tolerant species, reduced base flow and increased suspended solids. The drivers of these “symptoms” include impervious surfaces, piping in stormwater drainages, habitat and forest loss, water supply and sewer leaking, and direct alterations to channel morphology and flow. The goal of this study was to assess the integrity of the macroinvertebrate community and determine the most significant drivers of such integrity at the catchment, riparian zone, and reach scales. The study area included eight mixed land use (urban & agricultural) watersheds in Rock Island County, IL and Scott County, IA. Watersheds were delineated using Arc-GIS. Forty-one sampling sites were identified to capture the maximum variation in known drivers of watershed degradation. Macroinvertebrates were sampled using standard dip-netting techniques, with staples apportioned to different in-stream habitats weights by habitat abundance. Water quality data was collected monthly for the following parameters: total dissolved solids (TDS), total suspended solids (TSS) dissolved oxygen (DO), phosphate, and discharge. Sub-catchment basins above each sampling site were then delineated and used to quantify upstream landscape characteristics using available geospatial data including land cover, total impervious surface and within a 5m buffer of streams, etc. The family biotic index (FBI), a measure of integrity in relation to organic pollution tolerance was calculated

Assessing Intra-Event Phosphorus Dynamics in Drainage Water Using Phosphate Stable Oxygen Isotopes

Quantifying fluxes and pathways of dissolved reactive phosphorus (DRP) in tile-drained landscapes has been hampered by a lack of measurements that are sensitive to P fate and transport processes. One potential tool to help understand these dynamics is the oxygen isotope signature of phosphate (δ18OPO4); however, its potential benefits and limitations are not well understood for intra-event dynamics at the field scale. The objectives of this study were to quantify intra-event variability of δ18OPO4 signatures in tile drainage water and assess the efficacy of δ18OPO4 to elucidate mechanisms and flow pathways controlling DRP transport to tile drains. We collected water samples during a summer storm event from a subsurface (tile)-drained field located in west-central Ohio and analyzed for δ18OPO4 of DRP. Supplementary water quality measurements, hydrologic modeling, and soil temperature data were used to help understand intra-event δ18OPO4 dynamics. Results of the soil extraction analysis from our study site highlight that the soil water-extractable P (WEP) pool was not in equilibrium with long-term, temperature-dependent water isotope values. This result suggests that P-rich soils may, at least partially, retain their original source signature, which has significant implications for identifying hotspots of P delivery in watershed-scale applications. Results of the storm event analysis highlight that equilibration of leached DRP in soil water creates a gradient between isotopic compositions of pre-event shallow subsurface sources, pre-event deep subsurface sources, and the WEP tied up in surface soils. The current study represents the first intra-event analysis of δ18OPO4 and highlights the potential for phosphate oxygen isotopes as a novel tool to improve understanding of P fate and transport in artificially drained agroecosystems

Preferential Quadriceps Activation in Female Athletes with Incremental Increases in Landing Intensity

The purpose of this study was to identify alterations in preparatory muscle activation patterns across different drop heights in female athletes. Sixteen female high school volleyball players performed the drop vertical jump from three different drop heights. Surface electromyography of the quadriceps and hamstrings were collected during the movement trials. As the drop height increased, muscle activation of the quadriceps during preparatory phase also increased (p \u3c .05). However, the hamstrings activation showed no similar increases relative to drop height. Female athletes appear to preferentially rely on increased quadriceps activation, without an increase in hamstrings activation, with increased plyometric intensity. The resultant decreased activation ratio of the hamstrings relative to quadriceps before landing may represent altered dynamic knee stability and may contribute to the increased risk of ACL injury in female athletes