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White mold caused by the fungus, Sclerotinia sclerotiorum is a devastating disease of soybean (Glycine max) and other leguminous crops, including dry bean (Phaseolus vulgaris). Previous research has demonstrated that no-till planting soybean into rolled–crimped cereal rye residue can enhance weed management, improve soil health and reduce labor requirements in organic production. However, there are limited data on the effects of cereal rye residue on white mold suppression in no-till planted soybean and dry bean. Two field trials were conducted in 2016–2017 (Year 1) and repeated in 2017–2018 (Year 2) to evaluate the potential of cereal rye cover crop residue to suppress white mold in these crops. In each trial (soybean and dry bean), the experimental design was a randomized complete block with two treatments: (1) rolled–crimped cereal rye residue and (2) no cover crop control. Treatment effects on plant population, biomass and yield components varied between the main crops. Compared with the control treatment, cereal rye residue reduced the incidence of white mold in soybean in both years and in dry bean in Year 2. The reduction in white mold in cereal rye residue plots was due to a combination of (1) decreased sclerotial germination (no stipes formed) and (2) increased nonfunctional sclerotial germination defined here as sclerotia that germinated but produced stipes without the expanded cup where asci containing ascospores are formed. Weed density and biomass were lower in cereal rye residue plots in soybean and dry bean, except in Year 1 in soybean when weed biomass was low in both treatments. Our findings indicate that cereal rye residue could help organic and conventional farmers manage white mold in no-till planted soybean and dry bean. Germination of sclerotia resulting in nonfunctional apothecia could potentially exhaust soilborne inoculum in the upper soil profile and reduce infections in subsequent crops.
The Taipan galaxy survey (hereafter simply ‘Taipan’) is a multi-object spectroscopic survey starting in 2017 that will cover 2π steradians over the southern sky (δ ≲ 10°, |b| ≳ 10°), and obtain optical spectra for about two million galaxies out to z < 0.4. Taipan will use the newly refurbished 1.2-m UK Schmidt Telescope at Siding Spring Observatory with the new TAIPAN instrument, which includes an innovative ‘Starbugs’ positioning system capable of rapidly and simultaneously deploying up to 150 spectroscopic fibres (and up to 300 with a proposed upgrade) over the 6° diameter focal plane, and a purpose-built spectrograph operating in the range from 370 to 870 nm with resolving power R ≳ 2000. The main scientific goals of Taipan are (i) to measure the distance scale of the Universe (primarily governed by the local expansion rate, H0) to 1% precision, and the growth rate of structure to 5%; (ii) to make the most extensive map yet constructed of the total mass distribution and motions in the local Universe, using peculiar velocities based on improved Fundamental Plane distances, which will enable sensitive tests of gravitational physics; and (iii) to deliver a legacy sample of low-redshift galaxies as a unique laboratory for studying galaxy evolution as a function of dark matter halo and stellar mass and environment. The final survey, which will be completed within 5 yrs, will consist of a complete magnitude-limited sample (i ⩽ 17) of about 1.2 × 106 galaxies supplemented by an extension to higher redshifts and fainter magnitudes (i ⩽ 18.1) of a luminous red galaxy sample of about 0.8 × 106 galaxies. Observations and data processing will be carried out remotely and in a fully automated way, using a purpose-built automated ‘virtual observer’ software and an automated data reduction pipeline. The Taipan survey is deliberately designed to maximise its legacy value by complementing and enhancing current and planned surveys of the southern sky at wavelengths from the optical to the radio; it will become the primary redshift and optical spectroscopic reference catalogue for the local extragalactic Universe in the southern sky for the coming decade.
Tillage is a foundational management practice in many cropping systems. Although effective at reducing weed populations and preparing a crop seedbed, tillage and cultivation can also dramatically alter weed community composition. We examined the impact of soil tillage timing on weed community structure at four sites across the northeastern United States. Soil was tilled every 2 wk throughout the growing season (late April to late September 2013), and weed seedling density was quantified by species 6 wk after each tillage event. We used a randomized complete block design with four replicates for each tillage-timing treatment; a total of 196 plots were sampled. The timing of tillage was an important factor in shaping weed community composition and structure at all sites. We identified three main periods of tillage timing that resulted in similar communities. Across all sites, total weed density tended to be greatest and weed evenness tended to be lowest when soils were tilled early in the growing season. From the earliest to latest group of timings, total abundance decreased on average from 428±393 to 159±189 plants m−2, and evenness increased from 0.53±0.25 to 0.72±0.20. The effect of tillage timing on weed species richness varied by site. Our results show that tillage timing affects weed community structure, suggesting that farmers can manage weed communities and the potential for weed interference by adjusting the timing of their tillage and cropping practices.
Healthcare provider hands are an important source of intraoperative bacterial transmission events associated with postoperative infection development.
To explore the efficacy of a novel hand hygiene improvement system leveraging provider proximity and individual and group performance feedback in reducing 30-day postoperative healthcare-associated infections via increased provider hourly hand decontamination events.
Randomized, prospective study.
Dartmouth-Hitchcock Medical Center in New Hampshire and UMass Memorial Medical Center in Massachusetts.
Patients undergoing surgery.
Operating room environments were randomly assigned to usual intraoperative hand hygiene or to a personalized, body-worn hand hygiene system. Anesthesia and circulating nurse provider hourly hand decontamination events were continuously monitored and reported. All patients were followed prospectively for the development of 30-day postoperative healthcare-associated infections.
A total of 3,256 operating room environments and patients (1,620 control and 1,636 treatment) were enrolled. The mean (SD) provider hand decontamination event rate achieved was 4.3 (2.9) events per hour, an approximate 8-fold increase in hand decontamination events above that of conventional wall-mounted devices (0.57 events/hour); P<.001. Use of the hand hygiene system was not associated with a reduction in healthcare-associated infections (odds ratio, 1.07 [95% CI, 0.82–1.40], P=.626).
The hand hygiene system evaluated in this study increased the frequency of hand decontamination events without reducing 30-day postoperative healthcare-associated infections. Future work is indicated to optimize the efficacy of this hand hygiene improvement strategy.
The rate at which the poaching of rhinoceroses has escalated since 2010 poses a threat to the long-term persistence of extant rhinoceros populations. The policy response has primarily called for increased investment in military-style enforcement strategies largely based upon simple economic models of rational crime. However, effective solutions will probably require a context-specific, stakeholder-driven mix of top-down and bottom-up mechanisms grounded in theory that represents human behaviour more realistically. Using a problem-oriented approach we illustrate in theory and practice how community-based strategies that explicitly incorporate local values and institutions are a foundation for combating rhinoceros poaching effectively in specific contexts. A case study from Namibia demonstrates how coupling a locally devised rhinoceros monitoring regime with joint-venture tourism partnerships as a legitimate land use can reconcile individual values represented within a diverse stakeholder group and manifests as both formal and informal community enforcement. We suggest a social learning approach as a means by which international, national and regional governance can recognize and promote solutions that may help empower local communities to implement rhinoceros management strategies that align individual values with the long-term health of rhinoceros populations.
Atypical lymphoproliferative, histiocytic, and dendritic cell disorders often mimic their more common benign or malignant counterparts, and thus can easily be misdiagnosed. Although it may be challenging to identify these unusual disease entities precisely, doing so may significantly alter further evaluation, prognosis, and management of the patient. Multidisciplinary collaboration between clinicians and pathologists is often required to arrive at a definitive diagnosis. Critical to this process is obtaining adequate tissue, ideally through excisional lymph node biopsy. Although core-needle biopsy may sometimes yield a diagnosis, for many of these entities it will be inadequate. Fine needle aspiration has been demonstrated to be of little value in the diagnosis of lymphoproliferative disorders, as it does not provide an adequate assessment of tissue architecture. In cases where a biopsy is equivocal, additional biopsies may be necessary to establish a firm diagnosis.
In this chapter, we will summarize the pathophysiology, presentation, diagnosis, prognosis, and treatment of atypical lymphoproliferative, histiocytic, and dendritic cell disorders. Three main categories of these disorders have been defined (Table 17.1). Benign conditions, such as Kikuchi's disease, often behave indolently and can usually be managed with observation. Histiocytic disorders exhibit a wide range of behavior, and may require more aggressive therapies. Atypical lymphoproliferative disorders can be polyclonal, such as Castleman'sdisease, or malignant, such as lymphomatoid granulomatosis, and are treated in a variety of different ways.
Significant new opportunities for astrophysics and cosmology have been identified at low radio frequencies. The Murchison Widefield Array is the first telescope in the southern hemisphere designed specifically to explore the low-frequency astronomical sky between 80 and 300 MHz with arcminute angular resolution and high survey efficiency. The telescope will enable new advances along four key science themes, including searching for redshifted 21-cm emission from the EoR in the early Universe; Galactic and extragalactic all-sky southern hemisphere surveys; time-domain astrophysics; and solar, heliospheric, and ionospheric science and space weather. The Murchison Widefield Array is located in Western Australia at the site of the planned Square Kilometre Array (SKA) low-band telescope and is the only low-frequency SKA precursor facility. In this paper, we review the performance properties of the Murchison Widefield Array and describe its primary scientific objectives.
The Dominion Radio Astrophysical Observatory (DRAO) is carrying out a survey as part of an international collaboration to image the northe, at a common resolution, in emission from all major constituents of the interstellar medium; the neutral atomic gas, the molecular gas, the ionised gas, dust and relativistic plasma. For many of these constituents the angular resolution of the images (1 arcmin) will be more than a factor of 10 better than any previous studies. The aim is to produce a publicly-available database of high resolution, high-dynamic range images of the Galaxy for multi-phase studies of the physical states and processes in the interstellar medium. We will sketch the main scientific motivations as well as describe some preliminary results from the Canadian Galactic Plane Survey/Releve Canadien du Plan Galactique (CGPS/RCPG).
The future of centimetre and metre-wave astronomy lies with the Square Kilometre Array (SKA), a telescope under development by a consortium of 17 countries that will be 50 times more sensitive than any existing radio facility. Most of the key science for the SKA will be addressed through large-area imaging of the Universe at frequencies from a few hundred MHz to a few GHz. The Australian SKA Pathfinder (ASKAP) is a technology demonstrator aimed in the mid-frequency range, and achieves instantaneous wide-area imaging through the development and deployment of phased-array feed systems on parabolic reflectors. The large field-of-view makes ASKAP an unprecedented synoptic telescope that will make substantial advances in SKA key science. ASKAP will be located at the Murchison Radio Observatory in inland Western Australia, one of the most radio-quiet locations on the Earth and one of two sites selected by the international community as a potential location for the SKA. In this paper, we outline an ambitious science program for ASKAP, examining key science such as understanding the evolution, formation and population of galaxies including our own, understanding the magnetic Universe, revealing the transient radio sky and searching for gravitational waves.
Visible-blind UV cameras based on a 32 × 32 array of backside-illuminated GaN/AlGaN p-i-n photodiodes have been successfully demonstrated. The photodiode arrays were hybridized to silicon readout integrated circuits (ROICs) using In bump bonds. Output from the UV cameras were recorded at room temperature at frame rates of 30-240 Hz. These new visible-blind digital cameras are sensitive to radiation from 285-365 nm in the UV spectral region.