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Potential effectiveness of harvest weed seed control (HWSC) systems depends upon seed shatter of the target weed species at crop maturity, enabling its collection and processing at crop harvest. However, seed retention likely is influenced by agroecological and environmental factors. In 2016 and 2017, we assessed seed-shatter phenology in 13 economically important broadleaf weed species in soybean [Glycine max (L.) Merr.] from crop physiological maturity to 4 wk after physiological maturity at multiple sites spread across 14 states in the southern, northern, and mid-Atlantic United States. Greater proportions of seeds were retained by weeds in southern latitudes and shatter rate increased at northern latitudes. Amaranthus spp. seed shatter was low (0% to 2%), whereas shatter varied widely in common ragweed (Ambrosia artemisiifolia L.) (2% to 90%) over the weeks following soybean physiological maturity. Overall, the broadleaf species studied shattered less than 10% of their seeds by soybean harvest. Our results suggest that some of the broadleaf species with greater seed retention rates in the weeks following soybean physiological maturity may be good candidates for HWSC.
Seed shatter is an important weediness trait on which the efficacy of harvest weed seed control (HWSC) depends. The level of seed shatter in a species is likely influenced by agroecological and environmental factors. In 2016 and 2017, we assessed seed shatter of eight economically important grass weed species in soybean [Glycine max (L.) Merr.] from crop physiological maturity to 4 wk after maturity at multiple sites spread across 11 states in the southern, northern, and mid-Atlantic United States. From soybean maturity to 4 wk after maturity, cumulative percent seed shatter was lowest in the southern U.S. regions and increased moving north through the states. At soybean maturity, the percent of seed shatter ranged from 1% to 70%. That range had shifted to 5% to 100% (mean: 42%) by 25 d after soybean maturity. There were considerable differences in seed-shatter onset and rate of progression between sites and years in some species that could impact their susceptibility to HWSC. Our results suggest that many summer annual grass species are likely not ideal candidates for HWSC, although HWSC could substantially reduce their seed output during certain years.
We aimed to investigate the heterogeneity of seasonal suicide patterns among multiple geographically, demographically and socioeconomically diverse populations.
Weekly time-series data of suicide counts for 354 communities in 12 countries during 1986–2016 were analysed. Two-stage analysis was performed. In the first stage, a generalised linear model, including cyclic splines, was used to estimate seasonal patterns of suicide for each community. In the second stage, the community-specific seasonal patterns were combined for each country using meta-regression. In addition, the community-specific seasonal patterns were regressed onto community-level socioeconomic, demographic and environmental indicators using meta-regression.
We observed seasonal patterns in suicide, with the counts peaking in spring and declining to a trough in winter in most of the countries. However, the shape of seasonal patterns varied among countries from bimodal to unimodal seasonality. The amplitude of seasonal patterns (i.e. the peak/trough relative risk) also varied from 1.47 (95% confidence interval [CI]: 1.33–1.62) to 1.05 (95% CI: 1.01–1.1) among 12 countries. The subgroup difference in the seasonal pattern also varied over countries. In some countries, larger amplitude was shown for females and for the elderly population (≥65 years of age) than for males and for younger people, respectively. The subperiod difference also varied; some countries showed increasing seasonality while others showed a decrease or little change. Finally, the amplitude was larger for communities with colder climates, higher proportions of elderly people and lower unemployment rates (p-values < 0.05).
Despite the common features of a spring peak and a winter trough, seasonal suicide patterns were largely heterogeneous in shape, amplitude, subgroup differences and temporal changes among different populations, as influenced by climate, demographic and socioeconomic conditions. Our findings may help elucidate the underlying mechanisms of seasonal suicide patterns and aid in improving the design of population-specific suicide prevention programmes based on these patterns.
Having sufficient medical countermeasures (MCMs) available for the treatment of acetylcholinesterase-inhibiting nerve agent poisoned patients following a mass chemical exposure is a challenge for communities. After stockpiles containing auto-injectors are exhausted, communities need to be aware of alternative pharmaceutical options. The Department of Homeland Security Chemical Defense Program convened a federal interagency working group consisting of first responders, clinicians, and experts from the fields of medical toxicology, pharmacology, and emergency management. A literature review of pharmaceutical alternatives for treating nerve agent toxicity was performed. Pharmaceuticals that met the federal Public Health Emergency Medical Countermeasures Enterprise Product Specific Requirements were prioritized. Food and Drug Administration approval for one indication, market availability, and alignment to government procurement strategy were considered. This article summarizes the literature on comparative pharmacokinetics and efficacy against nerve agents (where available) of Food and Drug Administration approved drugs with muscarinic acetylcholine receptor antagonist and gamma-aminobutyric acid receptor agonist effects. This work is intended to serve as a resource of pharmaceutical options that may be available to communities (ie, emergency managers, planners, clinicians, and poison centers) when faced with a mass human exposure to a nerve agent and inadequate supplies of MCMs. (Disaster Med Public Health Preparedness. 2019;13:605-612)
Soybean consultants from Arkansas, Louisiana, southeast Missouri, Mississippi, and Tennessee were surveyed in 2016 to assess weed management practices and the prevalence of herbicide-resistant weeds in midsouthern U.S. soybean production. The consultants surveyed represented 13%, 28%, 8%, 16%, and 5% of the total soybean area planted in Arkansas, Louisiana, southeast Missouri, Mississippi, and Tennessee, respectively. Of the total scouted area, 78% of the consultants said their growers planted glyphosate-resistant soybean in 2016, with 18% planting glufosinate-resistant (LibertyLink®), primarily due to familiarity with and cost of the technology. Although 94% of the consultants determined that glufosinate was most effective on killing Palmer amaranth, the primary concern associated with controlling herbicide-resistant weeds was the associated cost, followed by return profit and time constraints. Palmer amaranth, morningglory species, horseweed, barnyardgrass, and Italian ryegrass were the five most problematic weeds in soybean across the five states. Palmer amaranth was the most problematic and important weed in each state individually. The increased concern (77% of consultants) with this species was attributed to the rising concern with and occurrence of protoporphyrinogen oxidase–resistant Palmer amaranth. Consultants were of the opinion that more research was needed on cover crops and the new traited technologies in order to improve weed management in soybean.
Inadvertent hyperthermia during anaesthesia is a rare but life-threatening complication. We have encountered several cases of severe hyperthermia in paediatric patients undergoing anaesthesia for cochlear implantation.
This study aimed to describe the clinical characteristics of children who developed hyperthermia while undergoing cochlear implantation, and to explore possible mechanisms and predisposing factors. The anaesthetic charts of all patients aged under 18 years who underwent cochlear implantation, or mastoid or ophthalmic surgery, between 1 January 2006 and 31 December 2009, at Soroka Medical Center in Beer Sheva, Israel, were reviewed. Patients undergoing mastoid and ophthalmic surgical procedures were used as controls.
A larger percentage of patients who underwent cochlear implant surgery (10 per cent) developed hyperthermia compared to controls (0.7 per cent, p < 0.05). In five of the seven cases, hyperthermia appeared in combination with tachycardia and hypercapnia, adhering to the clinical triad of malignant hyperthermia.
Patients undergoing cochlear implantation are susceptible to developing intra-operative hyperthermia. This article describes the hyperthermic events that occur during paediatric cochlear implantation, and attempts to identify potential triggers of hyperthermia.
We have completed a Chandra snapshot survey of 54 radio jets that are extended on arcsec scales. These are associated with flat spectrum radio quasars spanning a redshift range z=0.3 to 2.1. X-ray emission is detected from the jet of approximately 60% of the sample objects. We assume minimum energy and apply conditions consistent with the original Felten-Morrison calculations in order to estimate the Lorentz factors and the apparent Doppler factors. This allows estimates of the enthalpy fluxes, which turn out to be comparable to the radiative luminosities.
Recent research indicates that cognitive reserve mitigates the clinical expression of neuropsychological impairment in multiple sclerosis (MS). This literature primarily uses premorbid intelligence and lifetime experiences as indicators. However, changes in current recreational activities may also contribute to the maintenance of neural function despite brain atrophy. We examined the moderation effects of current changes in recreational activity on the relationship between brain atrophy and information processing speed in 57 relapsing-remitting MS patients. Current enrichment was assessed using the Recreation and Pastimes subscale from the Sickness Impact Profile. In patients reporting current declines in recreational activities, brain atrophy was negatively associated with cognition, but there was no such association in participants reporting stable participation. The MRI metric-by-recreational activity interaction was significant in separate hierarchical regression analyses conducted using third ventricle width, neocortical volume, T2 lesion volume, and thalamic volume as brain measures. Results suggest that recreational activities protect against brain atrophy's detrimental influence on cognition. (JINS, 2013, 19, 1–6)
To describe the implementation of an institution-wide, multiple-step intervention to curtail the epidemic spread of carbapenem-resistant Klebsiella pneumoniae (CRKP).
Consecutive intervention analyses.
Patients and Setting.
All patients admitted to a 775-bed tertiary care medical center in Jerusalem, Israel, from 2006 through 2010.
The effects of 4 interventions were assessed: (1) a policy of isolation for patients colonized or infected with CRKP in single rooms, which was started in March 2006; (2) cohorting of CRKP patients with dedicated nursing staff and screening of patients neighboring a patient newly identified as a carrier of CRKP, which was started in March 2007; (3) weekly active surveillance of intensive care unit patients, which was started during August 2008; and (4) selective surveillance of patients admitted to the emergency department, which was started in March 2009. Interrupted regression analysis and change-point analysis were used to assess the effect of each intervention on the CRKP epidemic.
Patient isolation alone failed to control the spread of CRKP, with incidence increasing to a peak of 30 new cases per 1,000 hospital beds per month. Institution of patient cohorting led to a steep decline in the incidence of CRKP acquisition (P< .001). Introduction of active surveillance interventions was followed by a decrease in the incidence of CRKP-positive clinical cultures but an increase in the incidence of CRKP-positive screening cultures. The mean prevalence of CRKP positivity for the period after cohorting began showed a statistically significant change from the mean prevalence in the preceding period (P< .001).
The cohorting of patients with dedicated staff, combined with implementation of focused active surveillance, effectively terminated the epidemic spread of CRKP. Cohorting reduced cross-infection within the hospital, and active surveillance allowed for earlier detection of carrier status. Both interventions should be considered in attempts to contain a hospital epidemic.
Public health and the emergency care community must work together to effectively achieve a state of community-wide disaster preparedness. The identification of model communities with good working relationships between their emergency care community and public health agencies may provide useful information on establishing and strengthening relationships in other communities. Seven model communities were identified: Boston, Massachusetts; Clark County, Nevada; Eau Claire, Wisconsin; Erie County, New York; Louisville, Kentucky; Livingston County, New York; and Monroe County, New York. This article describes these communities and provides a summary of common findings. Specifically, we recommend that communities foster respectful working relationships between agency leaders, hold regular face-to-face meetings, educate each other on their expertise and roles during a disaster, develop response plans together, work together on a day-to-day basis, identify and encourage a leader to facilitate these relationships, and share resources. (Disaster Med Public Health Preparedness. 2007;1:142–145)
We investigate the variations of the magnetic field, Doppler factor, and relativistic particle density along the jet of a quasar at z=0.72. We chose 4C 19.44 for this study because of its length and straight morphology. The 18 arcsec length of the jet provides many independent resolution elements in the Chandra X-ray image. The straightness suggests that geometry factors, although uncertain, are almost constant along the jet. We assume the X-ray emission is from inverse Compton scattering of the cosmic microwave background. With the aid of assumptions about jet alignment, equipartition between magnetic-field and relativistic-particle energy, and filling factors, we find that the jet is in bulk relativistic motion with a Doppler factor ≈ 6 at an angle no more than 10∘ to the line of sight over de-projected distances ≈ 150–600 kpc from the quasar, and with a magnetic field ≈10 μGauss.
Interactions between environmental conditions and management practices can significantly affect soil function. Soil quality assessments may improve our understanding of how soils interact with the hydrosphere and atmosphere. This information can then be used to develop management practices that improve the capacity of the soil to perform its various functions and help identify physical, chemical, and biological soil attributes to quantify the present state of a soil and detect changes resulting from management. In protocols established by the Great Plains cropping system network, sampling and testing procedures were selected to identify physical, chemical, and biological soil attributes responsive to management that may serve as useful indicators in assessing the effects of management on the soil resource. Eight existing long-term studies from throughout the Great Plains in the central USA were used to make these assessments because, (1) many years are required for certain soil properties to change measurably; (2) annual weather causes variation in system performance; and (3) the soil pools of interest are spatially variable. This paper includes detailed descriptions of the treatments and sites, and both long-term and short-term (1999–2002) data on precipitation, temperature, and yields for each location.
The electronic structure of the Pu-based superconductor PuCoGa5 and the Pauli paramagnet UCoGa5 is investigated using photoemission spectroscopy. The photoemission data of PuCoGa5 reveal features at the Fermi energy EF and about 1-1.5 eV below EF indicative of itinerant and localized f-electrons, respectively. Angle-resolved spectra of UCoGa5 show two peaks at similar energies that are highly dispersive, providing evidence for itinerant character of the f-electrons in this material. A comparison of the PuCoGa5 and UCoGa5 data to the spectra of α-Pu and δ-Pu serves to place PuCoGa5 within the context of the more general electronic structure problem in elemental Pu.
The standard method to determine the band structure of a condensed phase material is to (1) obtain a single crystal with a well defined surface and (2) map the bands with angle resolved photoelectron spectroscopy (occupied or valence bands) and inverse photoelectron spectroscopy (unoccupied or conduction bands). Unfortunately, in the case of Pu, the single crystals of Pu are either nonexistent, very small and/or having poorly defined surfaces. Furthermore, effects such as electron correlation and a large spin-orbit splitting in the 5f states have further complicated the situation. Thus, we have embarked upon the utilization of unorthodox electron spectroscopies, to circumvent the problems caused by the absence of large single crystals of Pu with well-defined surfaces. Our approach includes the techniques of resonant photoelectron spectroscopy , x-ray absorption spectroscopy [1,2,3,4], electron energy loss spectroscopy [2,3,4], Fano Effect measurements , and Bremstrahlung Isochromat Spectroscopy , including the utilization of micro-focused beams to probe single-crystallite regions of polycrystalline Pu samples. [2,3,6]
Time-resolved photoinduced reflectivity data were measured for the itinerant antiferromagnet UNiGa5 (TN ≈ 85 K) from room temperature down to 10 K. The relaxation time τ increases sharply near TN, which we attribute to the opening of a spin gap. In addition, at the lowest temperatures τ increases with a T1 dependence, which is similar to that shown by the heavy fermion YbAgCu4, but with no blocking of electron-phonon scattering within the DOS peak. The transient amplitude increase at TN with a temperature dependence that is consistent with the appearance of a spin gap.
As applications for extreme ultraviolet (EUV) radiation have been identified, the demand for better optics has also increased. Thorium and thorium oxide thin films (19 to 61 nm thick) were RF-sputtered and characterized using atomic force microscopy (AFM), spectroscopic ellipsometry, low-angle x-ray diffraction (LAXRD), x-ray photoelectron spectroscopy (XPS), and x-ray absorption near edge structure (XANES) in order to assess their capability as EUV reflectors. Their reflectance and absorption at different energies were also measured and analyzed at the Advanced Light Source in Berkeley. The reflectance of oxidized thorium is reported between 2 and 32 nm at 5, 10, and 15 degrees from grazing. The imaginary component of the complex index of refraction, β, is also reported between 12.5 and 18 nm. Thin films of thorium were found to reflect better between 6.5 and 9.4 nm at 5 degrees from grazing than all other known materials, including iridium, gold, nickel, uranium dioxide, and uranium nitride. The measured reflectance does not coincide with reflectance curves calculated from the Center for X-Ray Optics (CXRO) atomic scattering factor data. We observe large energy shifts of up to 20 eV, suggesting the need for better film characterization and possibly an update of the tabulated optical constants.