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Commercialization of 2,4-D–tolerant crops is a major concern for sweetpotato producers because of potential 2,4-D drift that can cause severe crop injury and yield reduction. A field study was initiated in 2014 and repeated in 2015 to assess impacts of reduced rates of 2,4-D, glyphosate, or a combination of 2,4-D with glyphosate on sweetpotato. In one study, 2,4-D and glyphosate were applied alone and in combination at 1/10, 1/100, 1/250, 1/500, 1/750, and 1/1,000 of anticipated field use rates (1.05 kg ha−1 for 2,4-D and 1.12 kg ha−1 for glyphosate) to ‘Beauregard’ sweetpotato at storage root formation (10 days after transplanting [DAP]). In a separate study, all these treatments were applied to ‘Beauregard’ sweetpotato at storage root development (30 DAP). Injury with 2,4-D alone or in combination with glyphosate was generally equal or greater than with glyphosate applied alone at equivalent herbicide rates, indicating that injury is attributable mostly to 2,4-D in the combination. There was a quadratic increase in crop injury and quadratic decrease in crop yield (with respect to most yield grades) with increased rate of 2,4-D applied alone or in combination with glyphosate applied at storage root development. However, neither the results of this relationship nor of the significance of herbicide rate were observed on crop injury or sweetpotato yield when herbicide application occurred at storage root formation, with a few exceptions. In general, crop injury and yield reduction were greatest at the highest rate (1/10×) of 2,4-D applied alone or in combination with glyphosate, although injury observed at lower rates was also a concern after initial observation by sweetpotato producers. However, in some cases, yield reduction of U.S. no.1 and marketable grades was also observed after application of 1/250×, 1/100×, or 1/10× rates of 2,4-D alone or with glyphosate when applied at storage root development.
A major concern of sweetpotato producers is the potential negative effects from herbicide drift or sprayer contamination events when dicamba is applied to nearby dicamba-resistant crops. A field study was initiated in 2014 and repeated in 2015 to assess the effects of reduced rates of N,N-Bis-(3-aminopropyl)methylamine (BAPMA) or diglycloamine (DGA) salt of dicamba, glyphosate, or a combination of these individually in separate trials with glyphosate on sweetpotato. Reduced rates of 1/10, 1/100, 1/250, 1/500, 1/750, and 1/1,000 of the 1× use rate of each dicamba formulation at 0.56 kg ha−1, glyphosate at 1.12 kg ha−1, and a combination of the two at aforementioned rates were applied to ‘Beauregard’ sweetpotato at storage root formation (10 d after transplanting) in one trial and storage root development (30 d after transplanting) in a separate trial. Injury with each salt of dicamba (BAPMA or DGA) applied alone or with glyphosate was generally equal to or greater than glyphosate applied alone at equivalent rates, indicating that injury is most attributable to the dicamba in the combination. There was a quadratic increase in crop injury and a quadratic decrease in crop yield (with respect to most yield grades) observed with an increased herbicide rate of dicamba applied alone or in combination with glyphosate applied at storage root development. However, with a few exceptions, neither this relationship nor the significance of herbicide rate was observed on crop injury or sweetpotato yield when herbicide application occurred at the storage root formation stage. In general, crop injury and yield reduction were greatest at the highest rate (1/10×) of either salt of dicamba applied alone or in combination with glyphosate, although injury observed at lower rates would be cause for concern after initial observation by sweetpotato producers. However, in some cases yield reduction of No.1 and marketable grades was observed following 1/250×, 1/100×, or 1/10× application rates of dicamba alone or with glyphosate when applied at storage root development.
The reported incidence of Clostridoides difficile infection (CDI) has increased in recent years, partly due to broadening adoption of nucleic acid amplification tests (NAATs) replacing enzyme immunoassay (EIA) methods. Our aim was to quantify the impact of this switch on reported CDI rates using a large, multihospital, empirical dataset.
We analyzed 9 years of retrospective CDI data (2009–2017) from 47 hospitals in the southeastern United States; 37 hospitals switched to NAAT during this period, including 24 with sufficient pre- and post-switch data for statistical analyses. Poisson regression was used to quantify the NAAT-over-EIA incidence rate ratio (IRR) at hospital and network levels while controlling for longitudinal trends, the proportion of intensive care unit patient days, changes in surveillance methodology, and previously detected infection cluster periods. We additionally used change-point detection methods to identify shifts in the mean and/or slope of hospital-level CDI rates, and we compared results to recorded switch dates.
For hospitals that transitioned to NAAT, average unadjusted CDI rates increased substantially after the test switch from 10.9 to 23.9 per 10,000 patient days. Individual hospital IRRs ranged from 0.75 to 5.47, with a network-wide IRR of 1.75 (95% confidence interval, 1.62–1.89). Reported CDI rates significantly changed 1.6 months on average after switching to NAAT testing (standard deviation, 1.9 months).
Hospitals that switched from EIA to NAAT testing experienced an average postswitch increase of 75% in reported CDI rates after adjusting for other factors, and this increase was often gradual or delayed.
In 2008, four decades since Meldgaard's work at Alarniq—the type site for Dorset culture—Savelle and Dyke returned to resurvey the site. Archaeological investigations continued in 2015 and 2017 as part of the Foxe Basin Archaeological Project, when Howse conducted further surveys, excavated six semi-subterranean dwellings and two associated middens, and tested five additional features. The new site map and radiocarbon sequence have significantly changed our understanding of site use and beach-level chronology at Alarniq. The number of dwellings varies across the beach ridges, suggesting populations fluctuated throughout the site's use (2,700–800 cal BP). However, the new radiocarbon analyses also indicate that dwellings between 14.5 and 21.5 m above sea level are the same general age and that paleodemography at Alarniq is less straightforward than suggested by the number of features per beach ridge. It appears that ideal house construction location is a stronger indicator of the placement of winter houses at the site than proximity to the shoreline. We suggest this is largely related to site seasonality. These new data have significant implications for our understanding of current Dorset artifact typologies that have largely been developed using the material Meldgaard recovered at the site.
Archaeological sites in the Canadian Arctic often contain substantial quantities of marine mammal bones and in some cases completely lack terrestrial mammal bones. A distrust of radiocarbon (14C) dates on marine mammal bones among Arctic archaeologists has caused many sites to be insufficiently dated. The goal of this study was to investigate the marine reservoir effect on Atlantic walrus in the Foxe Basin region of the Canadian Arctic through a two-pronged approach: dating of live-harvested specimens of known age collected prior to AD 1955 and dating of pairs of animal remains (walrus and caribou) from stratigraphically contemporaneous levels within archaeological features. 14C dates on pre-bomb, live-harvested walrus indicate that a ΔR value of 160±50 yr be used in calibrating dates on walrus from this region. These results differed significantly from a similar set of pre-bomb mollusks, which argues against applying mollusk-based corrections to marine mammals. The results of comparative dating of caribou and walrus from archaeological features provided maximum estimates of reservoir ages that were more varied than the directly measured ages. Although about half of inferred ΔR values overlap the museum specimen results, the others indicate that the assumption of contemporaneity does not hold true.
School leadership is critical to provide students with disabilities with opportunities to learn in inclusive schools. We summarise research about inclusive leadership, outlining factors that promoted and impeded inclusive schools in the United States. Next, we provide an example of a national collaboration between the Council of Chief State School Officers (CCSSO) and the Collaboration for Effective Educator Development, Accountability, and Reform (CEEDAR) Center that linked the Professional Standards for Educational Leaders (PSEL; National Policy Board for Educational Administration, 2015) to a supplemental guidance document, titled PSEL 2015 and Promoting Principal Leadership for the Success of Students With Disabilities. The latter illustrates what effective inclusive school leadership means for each of the 10 PSEL standards, and provides recommendations for improving leadership preparation and policy, including licensure. We also consider possible implications of this work for those in other countries, emphasising the need for widely understood and shared leadership practices and the need to link such practices to initial and ongoing leadership development.
Midpassages are the most recognizable architectural feature associated with the entire Paleoeskimo period (2800 BC–AD 1300) in the Canadian and Greenlandic Arctic. Usually built of stone, midpassages are rectangular-shaped axial structures that run through the center of tent rings and semisubterranean house depressions. However, a unique triangular form of midpassage developed in association with the Late Dorset complex in the Boothia Peninsula area of the Canadian Arctic around AD 400. Unlike the rectangular-shaped varieties that were built contemporaneously across the Arctic, distribution of the triangular form is limited, and occurrences are rare. Initially, construction appears restricted to the Boothia Peninsula region, where the form persisted for the subsequent 400 years. After AD 900, they are found in Inglefield Land, Greenland, and a few other locations in the Canadian Arctic where they continued to be built until around AD 1200, representing an over 800-year period in a remarkably unvarying configuration. Further, these triangular midpassage structures very likely represent a regional architectural variant that moved northward with the Late Dorset diaspora after AD 800.
Although researchers have developed evidence-based practices and identified other effective practices that show promise for improving outcomes for students with disabilities, these practices are all too frequently not used in inclusive classrooms. Some have posited that this research-to-practice gap may result because teachers lack confidence in these practices and do not find them feasible for use in their classrooms. More recently, researchers have begun to examine whether teacher education may contribute to this research-to-practice gap. We contend that teacher preparation is an important contributor to the research-to-practice gap, and discuss how teacher preparation might be changed to better prepare teachers to use effective practices in inclusive classrooms. Primary changes that are needed include identifying a set of high-leverage practices that serve as the core curriculum of teacher education and using a practice-based approach to systematically prepare future teachers to use these practices.
Loess is widespread over Alaska, and its accumulation has traditionally been associated with glacial periods. Surprisingly, loess deposits securely dated to the last glacial period are rare in Alaska, and paleowind reconstructions for this time period are limited to inferences from dune orientations. We report a rare occurrence of loess deposits dating to the last glacial period, ~19 ka to ~12 ka, in the Yukon-Tanana Upland. Loess in this area is very coarse grained (abundant coarse silt), with decreases in particle size moving south of the Yukon River, implying that the drainage basin of this river was the main source. Geochemical data show, however, that the Tanana River valley to the south is also a likely distal source. The occurrence of last-glacial loess with sources to both the south and north is explained by both regional, synoptic-scale winds from the northeast and opposing katabatic winds that could have developed from expanded glaciers in both the Brooks Range to the north and the Alaska Range to the south. Based on a comparison with recent climate modeling for the last glacial period, seasonality of dust transport may also have played a role in bringing about contributions from both northern and southern sources.
Regulatory impact analyses (RIAs) weigh the benefits of regulations against the burdens they impose and are invaluable tools for informing decision makers. We offer 10 tips for nonspecialist policymakers and interested stakeholders who will be reading RIAs as consumers.
1. Core problem: Determine whether the RIA identifies the core problem (compelling public need) the regulation is intended to address.
2. Alternatives: Look for an objective, policy-neutral evaluation of the relative merits of reasonable alternatives.
3. Baseline: Check whether the RIA presents a reasonable “counterfactual” against which benefits and costs are measured.
4. Increments: Evaluate whether totals and averages obscure relevant distinctions and trade-offs.
5. Uncertainty: Recognize that all estimates involve uncertainty, and ask what effect key assumptions, data, and models have on those estimates.
6. Transparency: Look for transparency and objectivity of analytical inputs.
7. Benefits: Examine how projected benefits relate to stated objectives.
8. Costs: Understand what costs are included.
9. Distribution: Consider how benefits and costs are distributed.
10. Symmetrical treatment: Ensure that benefits and costs are presented symmetrically.
The American Heart Association (AHA; Dallas, Texas USA) and European Resuscitation Council (Niel, Belgium) cardiac arrest (CA) guidelines recommend the intraosseous (IO) route when intravenous (IV) access cannot be obtained. Vasopressin has been used as an alternative to epinephrine to treat ventricular fibrillation (VF).
Limited data exist on the pharmacokinetics and resuscitative effects of vasopressin administered by the humeral IO (HIO) route for treatment of VF. The purpose of this study was to evaluate the effects of HIO and IV vasopressin, on the occurrence, odds, and time of return of spontaneous circulation (ROSC) and pharmacokinetic measures in a swine model of VF.
Twenty-seven Yorkshire-cross swine (60 to 80 kg) were assigned randomly to three groups: HIO (n=9), IV (n=9), and a control group (n=9). Ventricular fibrillation was induced and untreated for two minutes. Chest compressions began at two minutes post-arrest and vasopressin (40 U) administered at four minutes post-arrest. Serial blood specimens were collected for four minutes, then the swine were resuscitated until ROSC or 29 post-arrest minutes elapsed.
Fisher’s Exact test determined ROSC was significantly higher in the HIO 5/7 (71.5%) and IV 8/11 (72.7%) groups compared to the control 0/9 (0.0%; P=.001). Odds ratios of ROSC indicated no significant difference between the treatment groups (P=.68) but significant differences between the HIO and control, and the IV and control groups (P=.03 and .01, respectively). Analysis of Variance (ANOVA) indicated the mean time to ROSC for HIO and IV was 621.20 seconds (SD=204.21 seconds) and 554.50 seconds (SD=213.96 seconds), respectively, with no significant difference between the groups (U=11; P=.22). Multivariate Analysis of Variance (MANOVA) revealed the maximum plasma concentration (Cmax) and time to maximum concentration (Tmax) of vasopressin in the HIO and IV groups was 71753.9 pg/mL (SD=26744.58 pg/mL) and 61853.7 pg/mL (SD=22745.04 pg/mL); 111.42 seconds (SD=51.3 seconds) and 114.55 seconds (SD=55.02 seconds), respectively. Repeated measures ANOVA indicated no significant difference in plasma vasopressin concentrations between the treatment groups over four minutes (P=.48).
The HIO route delivered vasopressin effectively in a swine model of VF. Occurrence, time, and odds of ROSC, as well as pharmacokinetic measurements of HIO vasopressin, were comparable to IV.
BurgertJM, JohnsonAD, Garcia-BlancoJ, FultonLV, LoughrenMJ. The Resuscitative and Pharmacokinetic Effects of Humeral Intraosseous Vasopressin in a Swine Model of Ventricular Fibrillation. Prehosp Disaster Med. 2017;32(3):305–310.
The concepts of nature, culture and heritage are deeply entwined; their threads run together in some of our finest museums, in accounts of exploration and discovery, in the work of artists, poets andwriters, and in areas that are cherished and protected because of their landscapes and wildlife. The conservation ethic - placing a value on the natural environment - lies at the heart of the notion of "natural heritage", but we need to question how those values originated, were consolidated and ultimately moulded and changed over time. In a contemporary context the connections between nature andculture have sometimes become lost, fragmented, dislocated or misunderstood; where did "natural heritage" begin and how do we engage with the idea of "nature" today? The essays collected here re-evaluate the role of culture in developing the concept of natural heritage, reflecting on the shifts in its interpretation over the last 300 years.
Contributors: Martin Holdgate, Marie Addyman,E. Charles Nelson, Darrell Smith, Andrew Ramsey, Viktor Kouloumpis, Richard Milner, Gina Douglas, Penny Bradshaw, Arthur MacGregor, Chiara Nepi, Hannah Paddon, Stephen Hewitt, Gordon McGregor Reid, Ghillean T Prance, Peter Davis, Christopher Donaldson, Lucy McRobert, Sophie Darlington, Keith Scholey, Paul A. Roncken, Angus Lunn, Juliet Clutton-Brock, Tim Sands, Robert A. Lambert, James Champion,Erwin van Maanen, Heather Prince, Chris Loynes, Julie Taylor, Sarah Elmeligi, Samantha Finn, Owen Nevin, Jared Bowers, Kate Hennessy, Natasha Lyons, Mike Jeffries.