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We present a workflow to track icebergs in proglacial fjords using oblique time-lapse photos and the Lucas-Kanade optical flow algorithm. We employ the workflow at LeConte Bay, Alaska, where we ran five time-lapse cameras between April 2016 and September 2017, capturing more than 400 000 photos at frame rates of 0.5–4.0 min−1. Hourly to daily average velocity fields in map coordinates illustrate dynamic currents in the bay, with dominant downfjord velocities (exceeding 0.5 m s−1 intermittently) and several eddies. Comparisons with simultaneous Acoustic Doppler Current Profiler (ADCP) measurements yield best agreement for the uppermost ADCP levels (~ 12 m and above), in line with prevalent small icebergs that trace near-surface currents. Tracking results from multiple cameras compare favorably, although cameras with lower frame rates (0.5 min−1) tend to underestimate high flow speeds. Tests to determine requisite temporal and spatial image resolution confirm the importance of high image frame rates, while spatial resolution is of secondary importance. Application of our procedure to other fjords will be successful if iceberg concentrations are high enough and if the camera frame rates are sufficiently rapid (at least 1 min−1 for conditions similar to LeConte Bay).
The Orion facility at the Atomic Weapons Establishment in the United Kingdom has the capability to operate one of its two 500 J, 500 fs short-pulse petawatt beams at the second harmonic, the principal reason being to increase the temporal contrast of the pulse on target. This is achieved post-compression, using 3 mm thick type-1 potassium dihydrogen phosphate crystals. Since the beam diameter of the compressed pulse is
mm, it is impractical to achieve this over the full aperture due to the unavailability of the large aperture crystals. Frequency doubling was originally achieved on Orion using a circular sub-aperture of 300 mm diameter. The reduction in aperture limited the output energy to 100 J. The second-harmonic capability has been upgraded by taking two square 300 mm
300 mm sub-apertures from the beam and combining them at focus using a single paraboloidal mirror, thus creating a 200 J, 500 fs, i.e., 400 TW facility at the second harmonic.
Ecosystem services related to biodiversity, including cultural services, are essential for agricultural production such as viticulture. In agricultural landscapes, pesticides and mechanization threaten biodiversity, lead to landscape simplification and may reduce ecosystem services. On the other hand, consumers are more and more aware of environmental issues in food production. We investigated if landscape complexity, including soil management practices, was (i) appreciated by visitors and (ii) presented by winegrowers and tourism professionals in the French vineyards with the designation of geographical origin (DGO) ‘Coteaux du Layon’. Our goal was to determine if landscape complexity provides cultural ecosystem services such as aesthetics beneficial for the wine trade and the DGO region's attractiveness. We analyzed the iconographic content and the composition of landscape photographs on 50 websites to investigate if local winegrowers and tourism professionals associate biodiversity in the landscape and soil management practices with wine promotion. A questionnaire was realized to study the perception of local landscapes by interviewing 192 visitors of the region. The benefits of landscape complexity and soil management practices favoring biodiversity in viticulture were known and appreciated by many visitors, even if photographs of wine and traditional practices appeared to encourage wine purchasing. Local winegrowers’ representation of the DGO region only partially served these preferences; instead they mainly presented the wine-growing region by photographs focusing on wine bottles and vineyards. Consumer's preferences showed that complex landscapes could provide cultural ecosystem services that winegrowers are still less aware of. Therefore, complexity-targeted landscape planning including vegetation cover in soil management should be included in policy recommendations as agroecological measures for sustainable DGO production.
Purpose: We identified key clinicopathologic features of brain metastasis (BM) patients who are long-term survivors (LTS). Methods: We screened a prospective database of 1892 patients (treated 2006-2017), identified 92 (5%) who lived > 3 years following BM diagnosis, and performed per patient analyses. Results: Median age at diagnosis of BM was 57 years (range 19-77), 77% were women. The most common tumors were lung (50%), breast (26%), thyroid (7%) and skin (5%). 42% had tumors with drug-targetable oncoproteins (e.g. EGFR mutant) and 15% expressed hormonal receptors. ECOG was <2 in 70%. 47% had stage IV disease at diagnosis (75% with brain as the first site). 55% had controlled extracranial disease at the time of BM diagnosis. Median BM diameter was 1.5 cm (range 0.2-7) and 62% had a single lesion. Treatment was with surgery, radiosurgery, whole brain radiation (WBRT), or systemic therapy alone in 38%, 62%, 52%, and 4%, respectively. 53% received targeted- or immuno-therapy. Median follow up was 63 months (range 36-113). 61% failed intracranially at a median 24 months (range 1-99). 5 and 10- year survival (from BM diagnosis) was 82%, and 34%, respectively. Neither upfront WBRT nor other variables tested correlated with improved survival. In patients who died, an MRI was available within 3 months from death in 57%; of those 55% had no active intracranial disease, suggesting that the majority of deaths were non-neurologic. Conclusion: In general, LTS of BM had a limited number of BM, inactive extracranial disease, and drug targetable mutations.
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.
Epidemiological studies have identified increased colorectal cancer (CRC) risk with high red meat (HRM) intakes, whereas dietary fibre intake appears to be protective. In the present study, we examined whether a HRM diet increased rectal O6-methyl-2-deoxyguanosine (O6MeG) adduct levels in healthy human subjects, and whether butyrylated high-amylose maize starch (HAMSB) was protective. A group of twenty-three individuals consumed 300 g/d of cooked red meat without (HRM diet) or with 40 g/d of HAMSB (HRM+HAMSB diet) over 4-week periods separated by a 4-week washout in a randomised cross-over design. Stool and rectal biopsy samples were collected for biochemical, microbial and immunohistochemical analyses at baseline and at the end of each 4-week intervention period. The HRM diet increased rectal O6MeG adducts relative to its baseline by 21 % (P< 0·01), whereas the addition of HAMSB to the HRM diet prevented this increase. Epithelial proliferation increased with both the HRM (P< 0·001) and HRM+HAMSB (P< 0·05) diets when compared with their respective baseline levels, but was lower following the HRM+HAMSB diet compared with the HRM diet (P< 0·05). Relative to its baseline, the HRM+HAMSB diet increased the excretion of SCFA by over 20 % (P< 0·05) and increased the absolute abundances of the Clostridium coccoides group (P< 0·05), the Clostridiumleptum group (P< 0·05), Lactobacillus spp. (P< 0·01), Parabacteroides distasonis (P< 0·001) and Ruminococcus bromii (P< 0·05), but lowered Ruminococcus torques (P< 0·05) and the proportions of Ruminococcus gnavus, Ruminococcus torques and Escherichia coli (P< 0·01). HRM consumption could increase the risk of CRC through increased formation of colorectal epithelial O6MeG adducts. HAMSB consumption prevented red meat-induced adduct formation, which may be associated with increased stool SCFA levels and/or changes in the microbiota composition.
To explore GPs’ experiences of managing recurrent urinary tract infections (RUTIs) and their views on the use of herbal medicines for this condition.
RUTIs are an important problem commonly managed in primary care. Antibiotic prophylaxis is an effective treatment for acute infections but growing microbial resistance, adverse effects, and the lack of sustained long-term benefits mean that novel treatments are required. There are a number of promising reports of herbal medicines being used to treat RUTIs.
A total of 15 GPs (seven female; aged 34–59 years; in practice from 3 to 31 years) were purposively sampled and took part in semi-structured face-to-face and telephone interviews. Interviews were digitally recorded, transcribed, and analysed using inductive thematic analysis. Data collection and analysis proceeded iteratively to allow emerging themes to inform subsequent interviews.
Participants were aware of the disabling effect of RUTIs on women’s lives. GPs experienced significant challenges in their management of RUTIs with decisions about the provision of antibiotics being particularly complex. While some participants were open to the possibility of herbal treatment options they required more research into effectiveness and safety, better regulation of herbal practitioners, and assurance about herbal quality control and potential herb–drug interactions.
Several studies demonstrating that central line–associated bloodstream infections (CLABSIs) are preventable prompted a national initiative to reduce the incidence of these infections.
We conducted a collaborative cohort study to evaluate the impact of the national “On the CUSP: Stop BSI” program on CLABSI rates among participating adult intensive care units (ICUs). The program goal was to achieve a unit-level mean CLABSI rate of less than 1 case per 1,000 catheter-days using standardized definitions from the National Healthcare Safety Network. Multilevel Poisson regression modeling compared infection rates before, during, and up to 18 months after the intervention was implemented.
A total of 1,071 ICUs from 44 states, the District of Columbia, and Puerto Rico, reporting 27,153 ICU-months and 4,454,324 catheter-days of data, were included in the analysis. The overall mean CLABSI rate significantly decreased from 1.96 cases per 1,000 catheter-days at baseline to 1.15 at 16–18 months after implementation. CLABSI rates decreased during all observation periods compared with baseline, with adjusted incidence rate ratios steadily decreasing to 0.57 (95% confidence intervals, 0.50–0.65) at 16–18 months after implementation.
Coincident with the implementation of the national “On the CUSP: Stop BSI” program was a significant and sustained decrease in CLABSIs among a large and diverse cohort of ICUs, demonstrating an overall 43% decrease and suggesting the majority of ICUs in the United States can achieve additional reductions in CLABSI rates.
We report on an influenza B outbreak in an Ontario long-term care facility in which 2 immunized residents receiving oseltamivir prophylaxis for at least 5 days developed laboratory-confirmed influenza B infection. All isolates were tested for the most common oseltamivir resistance, and none of them had resistance identified.
Vertically aligned graphene was grown by plasma-enhanced chemical vapor deposition using methane feedstock. Optical emission spectroscopy (OES) was used to monitor the plasma species, and Raman spectroscopy was used for characterizing the properties of as-grown vertically aligned graphene. OES-derived information on plasma species, such as C, C2, CH, and H, are correlated with the properties of the vertically aligned graphene. Graphene grown at 250 W and 15 sccm exhibited the lowest amount of defects. Although OES peak intensities occurred at the highest power and lowest flow conditions, the OES peak ratios of plasma species had a greater dependence on flow rate and exhibited a saddle point in the atomic C/H ratio corresponding to optimal growth involving the lowest amount of overall defects. Plasma diagnostics provides a valuable approach to optimize growth characteristics and material properties.
It has been recognized since the 1960's that bombardment of a growing thin film by energetic particles strongly influences film properties. Particle bombardment has generally been accomplished by accelerating ions into the growing film. However, it has also been recognized since the 1960's that energetic particles reflected from the target influence the characteristics of films grown by physical sputtering and many experiments have been interpreted on this basis. A systematic study of the energy reflected from the surface by normally incident, singly charged noble-gas ions on five substrates of different masses has recently been published. This data along with sputter yields from the literature allow estimates to be made which were previously unavailable. The energy reflected from the target is carried away by electrons, sputtered particles and reflected ions (neutrals). The purpose of this paper is to provide basic information which will allow thin film scientists to estimate the influence of various experimental parameters on the amount of energy arriving at the growing film. The energy reflected from the target per sputtered atom will be given as a function of ion mass, target mass, and ion energy. TRIM.SP Monte Carlo calculations will be used to estimate the ratio of the energy carried away by sputtered atoms to that carried away by reflected ions. Calculations will also be used to estimate the average energy of the sputtered atoms as a function of ion mass, substrate mass and ion energy. It will be shown how this information can be used to guide the adjustment of experimental parameters in sputtering environments so as to control film characteristics.
Poor conductivity is a bottleneck hindering the production of nanocrystal-based devices. In most nanocrystal syntheses, ligands with long alkyl chains are used to prepare monodisperse, crystalline particles. When these nanocrystals are incorporated into devices as films, the bulky ligands form an insulating layer that prevents charge transfer between particles. While annealing or post-deposition chemical treatments can be used to strip surface ligands, each of these approaches has disadvantages. Here we demonstrate the use of a novel family of ligands comprised of primary alkyl dithiocarbamates to stabilize PbSe/CdSe core-shell nanocrystals. Primary dithiocarbamates, which can bind to cadmium and lead, are known to decompose to the corresponding sulfides when heated under mild conditions. In our scheme, PbSe/CdSe core-shell nanocrystals are first synthesized with standard ligands. These ligands are then exchanged to short chain dithiocarbamates in solution. When a film is cast and annealed at low temperature, the dithiocarbamates are removed. Electron microscopy reveals that the particles move closer together, and, along with x-ray diffraction, shows that the nanocrystals remain quantum confined. Transport measurements show a 10,000-fold increase in conductivity after annealing.
To better understand the specific charge transfer events that occur within a dye-sensitized solar cell (DSSC), we synthesized well-defined ZnO:dye dyads. The ZnO nanocrystals were synthesized following literature procedures from zinc acetate and a hydroxide source in ethanol. The absorption onset of the ZnO nanocrystals was observed using UV-vis measurements, from which estimated nanocrystal diameters were determined. At room temperature, the synthesis yielded nanocrystals ranging in diameter from 2-4 nm. Dispersions of ZnO nanocrystals in ethanol were mixed with solutions containing 5΄΄-phenyl-3΄,4΄-di(nbutyl)-[2,2΄:5΄,2΄΄] terthiophene-5-carboxylic acid. Using FT-IR and fluorescence spectroscopy, it was verified that the dye molecules were adsorbed to the ZnO surface via their carboxylate groups while the number of dye molecules adsorbed to the surface was quantified using a combination of techniques. Adsorption isotherms were employed to probe surface coverage of the dye onto the nanocrystals to yield an adsorption equilibrium constant of 1.5 ± 0.2 x 105 M-1. The ability of ZnO nanocrystals to quench the emission of the dye by an electron transfer mechanism was observed and elucidated using ultra-fast laser spectroscopy where the time-scale for electron injection from the dye to the ZnO was determined to be 5.5 ps.
Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate), or PEDOT:PSS, a conductive polymer suspension, as well as carbon nanotubes (CNTs), were incorporated into a conductive ink suitable for use in a piezoelectric inkjet printer. Viscosity, surface tension, and particle size of the ink were controlled to achieve stable, high-resolution printing. Passage of the CNTs through the filtration and jetting steps involved in printing was evaluated using scanning transmission electron microscopy (STEM), UV-visible spectroscopy, and zeta-potential measurements of the filtered and printed inks. Only single-walled nanotubes (SWCNTs) passed through the jetting stage in significant amounts. Printed PEDOT/SWCNT sheet resistance was effectively minimized at ˜1 kΩ/on cellulose acetate, in ink containing 6 w/w% of an aqueous SWCNT solution (approximately 0.04 w/w% SWCNTs).