Objectives/Goals: To explore the caregivers’ lived experiences related to facilitators of and barriers to effective primary care or neurology follow-up for children discharged from the pediatric emergency department (PED) with headaches. Methods/Study Population: We used the descriptive phenomenology qualitative study design to ascertain caregivers’ lived experiences with making follow-up appointments after their child’s PED visit. We conducted semi-structured interviews with caregivers of children with headaches from 4 large urban PEDs over HIPAA-compliant Zoom conferencing platform. A facilitator/co-facilitator team (JH and SL) guided all interviews, and the audio of which was transcribed using the TRINT software. Conventional content analysis was performed by two coders (JH and AS) to generate new themes, and coding disputes were resolved by team members using Atlas TI (version 24). Results/Anticipated Results: We interviewed a total of 11 caregivers (9 mothers, 1 grandmother, and 1 father). Among interviewees, 45% identified as White non-Hispanic, 45% Hispanic, 9% as African-American, and 37% were publicly insured. Participants described similar experiences in obtaining follow-up care that included long waits to obtain neurology appointments. Participants also described opportunities to overcome wait times that included offering alternative healthcare provider types as well as telehealth options. Last, participants described desired action while awaiting neurology appointments such as obtaining testing and setting treatment plans. Discussion/Significance of Impact: Caregivers perceived time to appointment as too long and identified practical solutions to ease frustrations while waiting. Future research should explore sharing caregiver experiences with primary care providers, PED physicians, and neurologists while developing plans to implement caregiver-informed interventions.

The first demonstration of laser action in ruby was made in 1960 by T. H. Maiman of Hughes Research Laboratories, USA. Many laboratories worldwide began the search for lasers using different materials, operating at different wavelengths. In the UK, academia, industry and the central laboratories took up the challenge from the earliest days to develop these systems for a broad range of applications. This historical review looks at the contribution the UK has made to the advancement of the technology, the development of systems and components and their exploitation over the last 60 years.

Although lignin has been negatively correlated with neutral-detergent fibre (NDF) digestibility (NDFD) in ruminants and used to predict potential extent of NDF digestion of forages, selection of an analysis, Klason lignin (KL) or acid-detergent lignin (ADL), to describe that the nutritionally relevant lignin has not been resolved. Dismissed as an artifact is the difference between KL and ADL (ΔL). A question is whether ΔL influences NDFD. We evaluated the relationships of ΔL, KL and ADL with NDFD in order to determine the nutritionally homogeneous or heterogeneous nature of KL. Data sets from two laboratories (DS1 and DS2) were used that included ADL, KL and in vitro NDFD at 48 h (NDFD48). DS1 contained seven C3 grasses, seventeen C4 maize forages and nineteen alfalfas, and DS2 had fifteen C3 grasses, eight C4 forages and six alfalfas. Mean ΔL was greater than ADL in C3 and C4 samples and less in alfalfas. Within forage type and laboratory, ΔL was not correlated with NDFD48 (r −0·34–0·49; all P > 0·17). ADL was more consistently correlated with NDFD48 (r −0·47–−0·95; P < 0·01–0·21) than with KL (r 0·03–−0·91; P < 0·01–0·94). ΔL as a proportion of KL was correlated with NDFD48 in C3 and C4 samples (r 0·44–0·76; P < 0·01–0·08). The differing behaviours of ΔL and ADL relative to NDFD48 indicate that KL is a nutritionally heterogeneous fraction, the behaviour of which may vary by forage type and ratios of ADL and ΔL present.

It is shown from studies of synthetic kaolinites doped with Fe3+ that the ESR spectrum of kaolinite at g = 4 consists of two components attributed to Fe3+ ions occupying two distinct substitutional sites (Centres I and II). The relative intensity of the two components can be correlated with the X-ray crystallinity of the samples. The ESR spectrum is influenced by artificial changes in crystallinity produced by subjecting samples to high stresses or by intercalation. It is concluded that Centre II is due to Fe3+ replacing Al3+ in the octahedral layer in a region of high crystallinity. Centre I is assigned to Fe3+ occupying Al3+ sites distorted by changes in the hydroxyl orientations associated with layer stacking disorder or disruption of interlayer bonding.

A stable defect centre in kaolinite which produces an ESR spectrum at g = 2·0 is attributed to either a hole centre located on an Si—O bond adjacent to an Mg2+ octahedral impurity or to an O2 − ion trapped within the lattice.

Synthetic kaolinites of varying crystallinity, and in some instances with ideal morphology, have been produced by hydrothermal reaction of aluminiosilicate gels. Synthetic kaolinites doped with Mg2+ and Fe3+ were also obtained.

Synthetic kaolinite doped with Fe3+ produced an ESR spectrum at g = 4 identical to spectra observed in natural kaolinites. Following X-irradiation and annealing at ~200°C, synthetic kaolinite doped with Mg2+ exhibited an ESR signal at g = 2·0 identical to a resonance observed in natural kaolinites. It is concluded that the g = 2·0 signal in kaolinite is due to a defect centre stabilized by Mg2+ substitution.

All synthetic and natural kaolinites exhibit an additional resonance at g = 2·0 following X-irradiation which can be repeatedly created and destroyed by irradiation and annealing. This resonance is attributed to defects possibly associated either with the substitution of Al3+ for Si4+ in kaolinite or with lattice vacancies.

We describe the design and performance of the Engineering Development Array, which is a low-frequency radio telescope comprising 256 dual-polarisation dipole antennas working as a phased array. The Engineering Development Array was conceived of, developed, and deployed in just 18 months via re-use of Square Kilometre Array precursor technology and expertise, specifically from the Murchison Widefield Array radio telescope. Using drift scans and a model for the sky brightness temperature at low frequencies, we have derived the Engineering Development Array’s receiver temperature as a function of frequency. The Engineering Development Array is shown to be sky-noise limited over most of the frequency range measured between 60 and 240 MHz. By using the Engineering Development Array in interferometric mode with the Murchison Widefield Array, we used calibrated visibilities to measure the absolute sensitivity of the array. The measured array sensitivity matches very well with a model based on the array layout and measured receiver temperature. The results demonstrate the practicality and feasibility of using Murchison Widefield Array-style precursor technology for Square Kilometre Array-scale stations. The modular architecture of the Engineering Development Array allows upgrades to the array to be rolled out in a staged approach. Future improvements to the Engineering Development Array include replacing the second stage beamformer with a fully digital system, and to transition to using RF-over-fibre for the signal output from first stage beamformers.

Halosulfuron-methyl, a sulfonylurea herbicide, was registered for broadleaf weed control in dry bean. This herbicide has an adequate margin of crop safety in white bean, but causes unacceptable injury to adzuki bean. Halosulfuron-methyl absorption, translocation, and metabolism were evaluated in white and adzuki bean using radiolabeled herbicide to determine if differences in these parameters could explain the difference in crop safety between these two species. Adzuki bean had more rapid halosulfuron-methyl absorption than white bean. Adzuki bean reached 90% absorption (t 90) 26.2 h after treatment (HAT), whereas white bean required 40.1 HAT to reach t 90. The maximum halosulfuron-methyl absorption was higher in adzuki bean (75.7%) than in white bean (65.3%). More 14C-halosulfuron was translocated to the apex, first trifoliate, stem above the treated leaf, and roots in aduzki bean than in white bean. The maximum radioactivity translocated out of treated leaf was higher in adzuki bean (17.7%) than in white bean (12.1%). Halosulfuron-methyl was broken down to the same metabolites in white and adzuki bean. The half-life of halosulfuron-methyl in adzuki bean was 16 HAT, compared with less than 6 HAT in white bean. More herbicide remained as the free acid in adzuki bean compared with white bean over the entire 48-h time course. The differential tolerance of white and adzuki bean to halosulfuron can be attributed to greater absorption and translocation and decreased metabolism in adzuki bean.

Morphologic and stratigraphic evidence shows that a late-glacial ice cap existed on part of the Eastern Cordillera of Ecuador (Lat. 0° 20′ S) on ground with a mean elevation of 4200 m where none exists now. An outlet glacier from an ca. 800 km2ice cap terminated at 3850 m altitude in the Papallacta valley on the eastern side of the plateau. Radiocarbon dates show that moraines formed by this advance were ice-free by 13,20014C yr B.P. Tephras and the age of organic deposits at the plateau edge indicate ice-free conditions before 11,80014C yr B.P. This interval was followed by the expansion of an ca. 140 km2ice cap that discharged glaciers into adjacent valleys where terminal moraines were built at 3950 m altitude. AMS and conventional radiocarbon dates from macrofossils, peat, and gyttja above and below till of the readvance indicate that the ice cap formed between ca. 11,000 and 10,00014C yr B.P. and was thus coeval with the European Younger Dryas event. The ice cap developed in response to a surface temperature cooling of at least 3°C in the tropical Andes, a finding that is consistent with a coupled equatorial/high latitude North Atlantic climate system operating at the late-glacial/Holocene transition. These results are further evidence that Younger Dryas cooling may have been a global event.

Saflufenacil is a PRE herbicide for the control of broadleaf weeds. Field and growth room studies were conducted to explore the tolerance of corn to POST treatments of saflufenacil and BAS 781. Additionally, the potential use of sodium as a safener for saflufenacil was evaluated. Crop injury caused by saflufenacil or BAS 781 was 8 and 38%, respectively, when applied at twice the recommended dose at the spike to two-leaf stage of crop growth. This injury increased to 28 and 65%, respectively, when applied at the three- to four-leaf stage. This level of crop injury resulted in yield loss, particularly when applied at the three- to four-leaf stage. The addition of Na-bentazon to saflufenacil reduced this injury and increased crop dry weight under both field and laboratory conditions. In the field, Na-bentazon also increased corn collar height and yield compared with saflufenacil applied alone. Na-bentazon reduced injury through a reduction in foliar uptake of saflufenacil. Sodium derived from baking soda also provided a safening effect, but only at the lowest dose of saflufenacil tested.

Background: Transient ischemic attack (TIA) and minor stroke are associated witha substantial risk of subsequent stroke; however, there is uncertainty aboutwhether such patients require admission to hospital for their initialmanagement. We used data from a clinical stroke registry to determine thefrequency and predictors of hospitalization for TIA or minor stroke acrossthe province of Ontario, Canada. Methods: The Ontario Stroke Registry collects information on apopulation-based sample of all patients seen in the emergency departmentwith acute stroke or TIA in Ontario. We identified patients with minorischemic stroke or TIA included in the registry between April 1, 2008, andMarch 31, 2011, and used multivariable analyses to evaluate predictors ofhospitalization. Results: Our study sample included 8540 patients with minor ischemic strokeor TIA, 47.2% of whom were admitted to hospital, with a range of 37.6% to70.3% across Ontario’s 14 local health integration network regions. Keypredictors of admission were preadmission disability, vascular risk factors,presentation with weakness, speech disturbance or prolonged/persistentsymptoms, arrival by ambulance, and presentation on a weekend or duringperiods of emergency department overcrowding. Conclusions: More than one-half of patients with minor stroke or TIA were notadmitted to the hospital, and there were wide regional variations inadmission patterns. Additional work is needed to provide guidance to healthcare workers around when to admit such patients and to determine whetherdischarged patients are receiving appropriate follow-up care.

The redshifted 21cm line of neutral hydrogen (Hi), potentially observable at low radio frequencies (~50–200 MHz), should be a powerful probe of the physical conditions of the inter-galactic medium during Cosmic Dawn and the Epoch of Reionisation (EoR). The sky-averaged Hi signal is expected to be extremely weak (~100 mK) in comparison to the foreground of up to 104 K at the lowest frequencies of interest. The detection of such a weak signal requires an extremely stable, well characterised system and a good understanding of the foregrounds. Development of a nearly perfectly (~mK accuracy) calibrated total power radiometer system is essential for this type of experiment. We present the BIGHORNS (Broadband Instrument for Global HydrOgen ReioNisation Signal) experiment which was designed and built to detect the sky-averaged Hi signal from the EoR at low radio frequencies. The BIGHORNS system is a mobile total power radiometer, which can be deployed in any remote location in order to collect radio frequency interference (RFI) free data. The system was deployed in remote, radio quiet locations in Western Australia and low RFI sky data have been collected. We present a description of the system, its characteristics, details of data analysis, and calibration. We have identified multiple challenges to achieving the required measurement precision, which triggered two major improvements for the future system.

The lowest frequency band (70–450 MHz) of the Square Kilometre Array (SKA) will consist of sparse aperture arrays grouped into geographically localised patches or stations. Signals from thousands of antennas in each station will be beamformed to produce station beams which form the inputs for the central correlator. Two-stage beamforming within stations can reduce SKA-low signal processing load and costs, but has not been previously explored for the irregular station layouts now favoured in radio astronomy arrays. This paper illustrates the effects of two-stage beamforming on sidelobes and effective area, for two representative station layouts (regular and irregular gridded tiles on an irregular station). The performance is compared with a single-stage, irregular station. The inner sidelobe levels do not change significantly between layouts, but the more distant sidelobes are affected by the tile layouts; regular tile creates diffuse, but regular, grating lobes. With very sparse arrays, the station effective area is similar between layouts. At lower frequencies, the regular tile significantly reduces effective area, hence sensitivity. The effective area is highest for a two-stage irregular station, but it requires a larger station extent than the other two layouts. Although there are cost benefits for stations with two-stage beamforming, we conclude that more accurate station modelling and SKA-low configuration specifications are required before design finalisation.