15,367 research outputs found
Aerosol major ion record at Mount Washington
This study examined the seasonal cycles and regional-scale meteorological controls on the chemical properties of bulk aerosols collected from 1999 to 2004 at Mount Washington, the highest peak in the northeastern United States. The concentrations of NH4+ and SO42− peaked during summer months. The pattern for aerosol NO3− was more complicated with relatively high median concentrations characterizing spring and summer months, but with major elevated events occurring during fall, winter, and spring. The seasonal relationship between NH4+ and SO42− indicated that during warmer months a mixture of (NH4)2SO4 and NH4HSO4 was present, while it was mainly the latter in winter. More acidity and higher concentrations of the major species were generally associated with winds from the southwest and west sectors. The highest (≥95th percentile) concentrations of SO42− and NH4+ were associated with air mass transport from major upwind source regions in the Midwest and along the eastern seaboard. The ionic composition and seasonal cycle observed at Mount Washington were similar to those measured at other northeastern sites, but the range and average concentrations were much lower. These differences were exaggerated during wintertime. Included in this paper are several Eulerian case studies of SO2 conversion to SO42− during transit from Whiteface Mountain, New York, to Mount Washington. The calculations suggest a gas-phase SO2 oxidation rate of ∼1–2% per hour and demonstrate the possibility of using these two sites to investigate the chemical evolution of air masses as they move from Midwestern source regions to northern New England
Exercise facilities for neurologically disabled populations : perceptions from the fitness industry
BACKGROUND:
People with neurological disabilities (pwND) face many barriers to undertaking physical activity. One option for exercise alongside formal physiotherapy is local fitness facilities but accessibility is often found wanting and gyms are seen as unwelcoming to pwND.
OBJECTIVE:
The objective of this exploratory study was to investigate the perceptions of fitness facility managers with respect to exercise for pwND in a gym environment. The aim was to identify potential barriers to provision by the fitness industry for pwND.
METHODS:
The participants included those who were in a position to influence provision at a policy level and those working at management level within fitness providers. A mixed methods approach was used: a quantitative questionnaire and 4 qualitative interviews. Descriptive and correlational analysis, thematic content analysis and concurrent triangulation analysis was undertaken.
RESULTS:
Specially trained staff is perceived to be necessary to make fitness facilities accessible for pwND.
CONCLUSIONS:
Ensuring the provision of specially trained staff to support pwND to exercise in gyms may be the main barrier to provision for this population. Investigation into the standard training of fitness professionals combining the expertise of neurological physiotherapists with that of fitness professionals to meet the needs of pwND would be advantageous
First record of verticillium wilt (Verticillium longisporum) in winter oilseed rape in the UK
Verticillium longisporum is an important pathogen of oilseed rape (OSR) and vegetable brassicas in several European countries, but has not been reported previously in the UK (Karapapa et al., 1997; Steventon et al., 2002). In 2007, Verticillium wilt was suspected in UK crops of winter OSR (W-OSR) on cv. Castille in Romney Marsh, Kent and on cv. Barrel near Hereford. At these two locations, 32 and 10% of the plants, respectively, appeared to be affected, but the presence of stem canker may have masked some infections. Symptoms were first seen as the crops began to ripen (seeds green-brown to brown, Growth Stage: 6,4-6,5) and included brown and dark grey vertical bands on the stems from soil level into the branches, and premature ripening of some branches (Fig. 1).
Microsclerotia were observed on stem samples collected in the field (Fig. 2), suggesting V. longisporum as the causal agent. Cultures were prepared from field samples by immersing stem pieces in 5% sodium hypochlorite solution for one minute, washing twice in sterile distilled water and plating onto potato dextrose agar containing 25 mg/l streptomycin sulphate. Isolates from three plants per outbreak were identified morphologically as V. longisporum. Mean conidial dimensions (25 spores per isolate) were 8.80-9.65 μm (length) and 2.50-2.85 μm (width) and all isolates produced elongated microsclerotia, characters typical of V. longisporum (Karapapa et al., 1997). The identity was confirmed by PCR using species-specific primers (Steventon et al., 2002) and, as a member of the α sub-group, by direct sequencing of the amplicons from primer pairs ITS4-ITS5 and DB19-DB22 (Collins et al., 2003; 2005). Sequences for isolate 003 from Kent were deposited in GenBank (Accession Nos. HQ702376 and HQ702377). All isolates tested from 2008 and 2009 were identical with previously deposited sequences for European OSR isolates (e.g. AF363992 and AF363246 respectively). Pathogenicity was confirmed by inoculating three OSR cv. Castille seedlings per isolate using the root dip technique with 1 x 106 spores/ml (Karapapa et al., 1997) under heated glasshouse conditions at 19°C. Leaf yellowing and blackening of the leaf veins were found 26 days after inoculation (Fig. 3). Yellowing affecting the three oldest leaves increased for seven to nine days. After five weeks the final mean leaf area affected was 63-78% with no differences between isolates. No leaf yellowing occurred in the controls. After five weeks, V. longisporum was re-isolated from all the inoculated seedlings, but not from the non-inoculated controls.
In June 2008, infection of W-OSR crops in different fields on the same farms was found on cv. Es Astrid in Kent (56% incidence) and on cv. Lioness in Hereford (15% incidence). The Kent farm had been growing W-OSR alternating with winter wheat for at least 10 years whilst the Hereford farm had grown W-OSR one year in four. These short rotations of OSR may be contributing to the appearance of this disease. This study confirms the identification of V. longisporum on any host in the UK, through molecular studies and detailed spore measurements that were not reported in an earlier review (Gladders, 2009). This pathogen occurs in several European countries and, since OSR may be traded freely, following a Defra consultation, no statutory plant health action is to be taken
Experimental and theoretical lifetimes and transition probabilities in Sb I
We present experimental atomic lifetimes for 12 levels in Sb I, out of which
seven are reported for the first time. The levels belong to the 5p(P)6s
P, P and 5p(P)5d P, F and F terms. The
lifetimes were measured using time-resolved laser-induced fluorescence. In
addition, we report new calculations of transition probabilities in Sb I using
a Multiconfigurational Dirac-Hartree-Fock method. The physical model being
tested through comparisons between theoretical and experimental lifetimes for
5d and 6s levels. The lifetimes of the 5d F levels (19.5,
7.8 and 54 ns, respectively) depend strongly on the -value. This is
explained by different degrees of level mixing for the different levels in the
F term.Comment: 10 page
Percutaneous Endoscopic Gastrostomy in the Super-Morbidly Obese Patient
INTRODUCTION: Obesity is reaching epidemic proportions in the United States, and as patients at the extremes of morbid obesity come under the care of surgeons, routine procedures may become increasingly complex in the face of greater body mass. We prospectively evaluated the success rate of percutaneous endoscopic gastrostomy (PEG) placement in a group of morbidly obese patients outside the current classification systems used to stratify obesity.
METHODS: Patients with a body mass index (BMI) greater than 60 kg/m2 who presented for PEG over a one year period were prospectively enrolled. Each patient underwent attempted PEG placement using the pull method by a single surgeon. Outcome variables included: successful PEG, wound infection, tube dislodgement, or bleeding.
RESULTS: Six patients with BMI \u3e 60 kg/m2 presented for PEG. All patients were in a surgical critical care unit maintained on mechanical ventilation. All underwent successful PEG placement with standard techniques and sustained no post-procedural complications.
CONCLUSION: In the hands of an experienced surgical endoscopist, percutaneous endoscopic gastrostomy can be safely performed in patients at the extremes of morbid obesity. Future studies are warranted to validate the results of our small series
Replicators in Fine-grained Environment: Adaptation and Polymorphism
Selection in a time-periodic environment is modeled via the two-player
replicator dynamics. For sufficiently fast environmental changes, this is
reduced to a multi-player replicator dynamics in a constant environment. The
two-player terms correspond to the time-averaged payoffs, while the three and
four-player terms arise from the adaptation of the morphs to their varying
environment. Such multi-player (adaptive) terms can induce a stable
polymorphism. The establishment of the polymorphism in partnership games
[genetic selection] is accompanied by decreasing mean fitness of the
population.Comment: 4 pages, 2 figure
Summary of the 13th IACHEC Meeting
We summarize the outcome of the 13th meeting of the International
Astronomical Consortium for High Energy Calibration (IACHEC), held at Tenuta
dei Ciclamini (Avigliano Umbro, Italy) in April 2018. Fifty-one scientists
directly involved in the calibration of operational and future high-energy
missions gathered during 3.5 days to discuss the current status of the X-ray
payload inter-calibration and possible approaches to improve it. This summary
consists of reports from the various working groups with topics ranging from
the identification and characterization of standard calibration sources,
multi-observatory cross-calibration campaigns, appropriate and new statistical
techniques, calibration of instruments and characterization of background, and
communication and preservation of knowledge and results for the benefit of the
astronomical community.Comment: 12 page
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