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Wind-driven snow redistribution can increase the spatial heterogeneity of snow accumulation on ice caps and ice sheets, and may prove crucial for the initiation and survival of glaciers in areas of marginal glaciation. We present a snowdrift model (Snow_Blow), which extends and improves the model of Purves, Mackaness and Sugden (1999, Journal of Quaternary Science 14, 313–321). The model calculates spatial variations in relative snow accumulation that result from variations in topography, using a digital elevation model (DEM) and wind direction as inputs. Improvements include snow redistribution using a flux routing algorithm, DEM resolution independence and the addition of a slope curvature component. This paper tests Snow_Blow in Antarctica (a modern environment) and reveals its potential for application in palaeoenvironmental settings, where input meteorological data are unavailable and difficult to estimate. Specifically, Snow_Blow is applied to the Ellsworth Mountains in West Antarctica where ablation is considered to be predominantly related to wind erosion processes. We find that Snow_Blow is able to replicate well the existing distribution of accumulating snow and snow erosion as recorded in and around Blue Ice Areas. Lastly, a variety of model parameters are tested, including depositional distance and erosion vs wind speed, to provide the most likely input parameters for palaeoenvironmental reconstructions.
To sustainably improve cleaning of high-touch surfaces (HTSs) in acute-care hospitals using a multimodal approach to education, reduction of barriers to cleaning, and culture change for environmental services workers.
The study was conducted in 2 academic acute-care hospitals, 2 community hospitals, and an academic pediatric and women’s hospital.
Frontline environmental services workers.
A 5-module educational program, using principles of adult learning theory, was developed and presented to environmental services workers. Audience response system (ARS), videos, demonstrations, role playing, and graphics were used to illustrate concepts of and the rationale for infection prevention strategies. Topics included hand hygiene, isolation precautions, personal protective equipment (PPE), cleaning protocols, and strategies to overcome barriers. Program evaluation included ARS questions, written evaluations, and objective assessments of occupied patient room cleaning. Changes in hospital-onset C. difficile infection (CDI) and methicillin-resistant S. aureus (MRSA) bacteremia were evaluated.
On average, 357 environmental service workers participated in each module. Most (93%) rated the presentations as ‘excellent’ or ‘very good’ and agreed that they were useful (95%), reported that they were more comfortable donning/doffing PPE (91%) and performing hand hygiene (96%) and better understood the importance of disinfecting HTSs (96%) after the program. The frequency of cleaning individual HTSs in occupied rooms increased from 26% to 62% (P < .001) following the intervention. Improvement was sustained 1-year post intervention (P < .001). A significant decrease in CDI was associated with the program.
A novel program that addressed environmental services workers’ knowledge gaps, challenges, and barriers was well received and appeared to result in learning, behavior change, and sustained improvements in cleaning.
Background: Neonatal hypoxic ischemic encephalopathy (HIE) is a clinical phenomenon, that often results from pre or perinatal reduced cerebral blood flow and/or hypoxemia. However, in some cases, neonates present with HIE without significant risk factors or have an unusual clinical course. With the advent of advanced genetic testing, we aimed to explore if such infants had genetic risk factors predisposing them to an HIE-phenotype. Methods: We reviewed 206 charts of infants meeting local protocol criteria for moderate to severe HIE at Level III NICU’s in Calgary, Alberta. Of these, 27 patients had genetic testing such as microarray, whole exome sequencing, or gene panels. Results: Six/twenty-seven patients had genetic mutations; two CDKL5 mutations (protein kinase), one CFTR mutation (cystic fibrosis), one PDH deficiency, one CYP21A2 mutation (congenital adrenal hyperplasia), and one ISY1 (VUS; pre-mRNA splicing). Two patients had noted difficult deliveries and four had minor complications, but all were out of keeping with the severity of presumed HIE. Conclusions: This preliminary study demonstrates a possible association between genetic co-morbidities and predisposition towards HIE in the context of a relatively uneventful pre/perinatal course. Earlier identification of genetic etiology, recognized by a discrepancy between risk factors and clinical presentation, could aid in treatment decisions and outcome prognostication.
To assess produce availability, quality and price in a large sample of food stores in low-income neighbourhoods in California.
Cross-sectional statewide survey.
Between 2011 and 2015, local health departments assessed store type, WIC (Supplemental Nutrition Program for Women, Infants, and Children)/SNAP (Supplemental Nutrition Assistance Program) participation, produce availability, quality and price of selected items in stores in low-income neighbourhoods. Secondary data provided reference chain supermarket produce prices matched by county and month. t Tests and ANOVA examined differences by store type; regression models examined factors associated with price.
Large grocery stores (n 231), small markets (n 621) and convenience stores (n 622) in 225 neighbourhoods.
Produce in most large groceries was rated high quality (97 % of fruits, 98 % of vegetables), but not in convenience stores (25 % fruits, 14 % vegetables). Small markets and convenience stores participating in WIC and/or SNAP had better produce availability, variety and quality than non-participating stores. Produce prices across store types were, on average, higher than reference prices from matched chain supermarkets (27 % higher in large groceries, 37 % higher in small markets, 102 % higher in convenience stores). Price was significantly inversely associated with produce variety, adjusting for quality, store type, and SNAP and WIC participation.
The study finds that fresh produce is more expensive in low-income neighbourhoods and that convenience stores offer more expensive, poorer-quality produce than other stores. Variety is associated with price and most limited in convenience stores, suggesting more work is needed to determine how convenience stores can provide low-income consumers with access to affordable, high-quality produce. WIC and SNAP can contribute to the solution.
We present seismic and radar data from the onset region of Rutford Ice Stream, West Antarctica, which show the form and internal structure of a variety of bed forms beneath an active ice stream. The ice flow in the area of our survey accelerates from 72 to >200 m a–1, the ice is 2200–3200 m thick, and the bed of the ice stream lies up to 2000 m below present sea level. We have imaged the internal structure of the bed forms with seismic reflection techniques and also observed radar reflections from below the bed in some circumstances. We observed a transverse moraine 2 km wide and 1.5 km long beneath the slower-flowing part of the ice stream, which we interpret to be composed of unconsolidated sediment undergoing active deformation near the ice–sediment interface. We observed drumlins of classical form with elongation ratios of between 1:1.5 and 1:4.0 where the surface flow speed exceeded 95 m a–1. The conformity of the internal structure of the bed forms with the ice base suggests that the bed forms are active depositional features in congruence with the observation of a contemporary drumlin-forming episode in the distal part of the same ice stream. These observations provide the first direct evidence of the association between ice-stream flow speed and bed-form shape.
In glacial environments particle-size analysis of moraines provides insights into clast origin, transport history, depositional mechanism and processes of reworking. Traditional methods for grain-size classification are labour-intensive, physically intrusive and are limited to patch-scale (1 m2) observation. We develop emerging, high-resolution ground- and unmanned aerial vehicle-based ‘Structure-from-Motion’ (UAV-SfM) photogrammetry to recover grain-size information across a moraine surface in the Heritage Range, Antarctica. SfM data products were benchmarked against equivalent datasets acquired using terrestrial laser scanning, and were found to be accurate to within 1.7 and 50 mm for patch- and site-scale modelling, respectively. Grain-size distributions were obtained through digital grain classification, or ‘photo-sieving’, of patch-scale SfM orthoimagery. Photo-sieved distributions were accurate to <2 mm compared to control distributions derived from dry-sieving. A relationship between patch-scale median grain size and the standard deviation of local surface elevations was applied to a site-scale UAV-SfM model to facilitate upscaling and the production of a spatially continuous map of the median grain size across a 0.3 km2 area of moraine. This highly automated workflow for site-scale sedimentological characterization eliminates much of the subjectivity associated with traditional methods and forms a sound basis for subsequent glaciological process interpretation and analysis.
In this study, we used an online survey to assess knowledge, attitudes, and practices related to environmental cleaning and other infection prevention strategies among environmental services workers (ESWs) at 5 hospitals. Our findings suggest that ESWs could benefit from additional education and feedback as well as new strategies to address workflow challenges.
Spatial studies of the emission line regions in planetary nebulae (PN) can provide insight into the physical and chemical environments across the nebulae. In a collaborative effort by the coauthors, a K-band Fabry-Perot etalon has been coupled with an advanced 256 × 256 InSb focal plane array at the Wyoming Infrared Observatory 2.3m telescope. This system permits us to obtain spatially resolved, 0.24″/pixel, moderate spectral resolution (R ≈ 800), flux-density IR emission line images of astronomical sources. We obtained continuum-subtracted images of Br γ, HeI 2.06 μm, the 2-μm UIR features, and the 3.3 μm PAH dust feature in the PN NGC 6572, NGC 7027, and NGC 7662. One objective was to determine the spatial morphology of two unidentified emission lines, UIR1−2.199 μm, and UIR2−2.287 μm (Geballe et al. 1991). These UIR lines appear in the spectra of many PN (Hora et al. 1997) and in the Orion Nebula (Luhman & Rieke 1996). Geballe et al. suggested that the UIR lines are most likely forbidden transitions and showed that the parent ion ionization potential is ≈ 30–40 eV, while the ionization potential for the ions themselves is 40–60 eV. Here we directly compare the distribution of the UIR emitters to that of the gas (H+,He+) and dust (PAHs).
The evolution of planetary nebulae is controlled largely by hardening of the radiation field from the central star and by hydrodynamic interactions between the “fast wind” and the slower red giant wind. These processes also result in the heating and dissociation of H2 and in the production of H2 vibration–rotation lines in the near-infrared. Both mechanisms tend to produce high gas temperatures and, at high densities, a thermal population of states. Kinematic studies provide vital information on the geometry and expansion of the nebulae and offer a discriminant between shocked and photodissociated regions.
Sauropod dinosaurs were the largest terrestrial animals and their growth rates remain a subject of debate. By counting growth lines in histologic sections and relating bone length to body mass, it has been estimated that Apatosaurus attained its adult body mass of about 25,000 kg in as little as 15 years, with a maximum growth rate over 5000 kg/yr. This rate exceeds that projected for a precocial bird or eutherian mammal of comparable estimated body mass. An alternative method of estimating limb length and body mass for each growth line, and fitting the resulting age/mass data to the von Bertalanffy growth equation, yields a revised growth curve suggesting that Apatosaurus adult mass was reached by 70 years with a maximum growth rate of 520 kg/yr. This alternative method for growth rate determination can also be applied to histological studies of other sauropods. At only about half the mass of Apatosaurus, Janenschia took between 20 and 30 years to attain its adult size (over 14,000 kg). This result is supported by independent evidence of estimated bone apposition rates. Despite having an adult body mass greater than Apatosaurus, the titanosaurid Alamosaurus attained a mass over 32,000 kg within 45 years and a maximum growth rate of 1000 kg/yr. Titanosaurids may have been the fastest growing of all sauropods. Even so, sauropod growth rate estimates produced using the von Bertalanffy equation fall between those projected for reptiles and those for precocial birds of equivalent projected body mass. These results are comparable to those found for smaller dinosaurs, and suggest that sauropods grew at rates similar to other dinosaurs in spite of their great size.
In the debate over the reality of race, a three-way dispute has become entrenched: race is biologically real, socially real, or simply not real. These three theses have each enjoyed increasingly sophisticated defenses over roughly the past thirty years, but we argue here that this debate contains a lacuna: there is a fourth, mostly neglected, position that we call ‘basic racial realism.’ Basic racial realism says that though race is neither biologically real nor socially real, it is real all the same. Our goal is to establish this theory's credentials and provide it with initial support. It appears to be in a strong dialectical position and to nicely capture what many want from a theory of race.
Excavations at Sparta have cleared up many of the problems connected with the class of pottery now definitely recognised as Laconian, but the great number of the mythological scenes, found mainly on kylikes, form a group quite distinct in spirit and design from the other types of decoration used on Laconian ware, and it is still a question whether the vases with these scenes (nearly all of them found outside Greece) could really have come from the workshops which turned out the vases found in Spartan soil. There must be some distinct and powerful cause, lying outside the normal growth of local artistic tradition, to account for this new development, and this cause, as I will try to shew, seems to be the coming of Bathycles of Magnesia to build the great Throne of Apollo at Amyclae.
To quantify myocardial blood flow in infants and children with mild or moderate aortic stenosis using adenosine-infusion cardiac magnetic resonance.
It is unclear whether asymptomatic children with mild/moderate aortic stenosis have myocardial abnormalities. In addition, cardiac magnetic resonance-determined normative myocardial blood flow data in children have not been reported.
We studied 31 infants and children with either haemodynamically normal hearts (n=20, controls) or mild/moderate aortic stenosis (n=11). The left ventricular myocardium was divided into six segments, and the change in average segmental signal intensity during contrast transit was used to quantify absolute flow (ml/g/minute) at rest and during adenosine infusion by deconvolution of the tissue curves with the arterial input of contrast.
In all the cases, adenosine was well tolerated without complications. The mean pressure gradient between the left ventricle and the ascending aorta was higher in the aortic stenosis group compared with controls (24 versus 3 mmHg, p<0.001). Left ventricular wall mass was slightly higher in the aortic stenosis group compared with controls (65 versus 50 g/m2, p<0.05). After adenosine treatment, both the absolute increase in myocardial blood flow (p<0.0001) and the hyperaemic flow significantly decreased (p<0.001) in children with mild/moderate aortic stenosis compared with controls.
Abnormal myocardial blood flow in children with mild/moderate aortic stenosis may be an important therapeutic target.
We report on the preparation and characterization of crystalline bismuth oxide thin films via Biased Target Ion Beam Deposition method. A focused blue laser (405nm) is used to write an array of dots in the bismuth oxide thin film and demonstrate clear and circular recording marks in form of “bubbles” or “little volcanos” (FWHM ∼500nm). Results indicate excellent static recording characteristics, writing sensitivity and contrast. The recording mechanism is investigated and is believed to be related to laser-induced morphology change.
This report, in which the usual arrangement is adopted, includes all the excavation-accounts which have reached me up to September 30th, 1929. Those concerning the work of the French School, the German School and the Greek Archaeological Service relate to work done in 1928; the rest mainly concern the campaigns of 1929.
During the season of 1929 the American School, under Professor Rhys Carpenter, have continued their work on Old Corinth, selecting three areas for excavation:—the first, just north of the Peribolos of Apollo and east of the Lechaeum Road, revealed a large though much-destroyed Roman thermal establishment, where the well-preserved floor-piers of two hypocaust rooms and a deep marble-lined pool leave no doubt as to the purpose of the building, identified by Professor Carpenter with the famous Baths of Eurykles, described by Pausanias. The second area lies between the Temple of Apollo and the village road on the north. In antiquity the rocky hill on which the Temple stood had been cut away to a vertical rock-face, some 20 feet high, and Professor Carpenter's purpose is to restore the ancient isolation of the Temple.