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Terrestrial gastropods are problematical for radiocarbon (14C) measurement because they tend to incorporate carbon from ancient sources as a result of their dietary behavior. The 14C ecology of the pulmonate land snail, Helix melanostoma in Cyrenaica, northeastern Libya, was investigated as part of a wider study on the potential of using terrestrial mollusk shell for 14C dating of archaeological deposits. H. melanostoma was selected out of the species available in the region as it has the most predictable 14C ecology and also had a ubiquitous presence within the local archaeology. The ecological observations indicate that H. melanostoma has a very homogenous 14C ecology with consistent variations in F14C across sample sites controlled by availability of dietary vegetation. The majority of dated specimens from non-urbanized sample locations have only a small old-carbon effect, weighted mean of 476±48 14C yr, with between ~1% and 9% of dietary F14C from non-organic carbonate sources. Observed instabilities in the 14C ecology can all be attributed to the results of intense human activity not present before the Roman Period. Therefore, H. melanostoma and species with similar ecological behavior are suitable for 14C dating of archaeological and geological deposits with the use of a suitable offset.
A regional offset (ΔR) from the marine radiocarbon calibration curve is widely used in calibration software (e.g. CALIB, OxCal) but often is not calculated correctly. While relatively straightforward for known-age samples, such as mollusks from museum collections or annually banded corals, it is more difficult to calculate ΔR and the uncertainty in ΔR for 14C dates on paired marine and terrestrial samples. Previous researchers have often utilized classical intercept methods that do not account for the full calibrated probability distribution function (pdf). Recently, Soulet (2015) provided R code for calculating reservoir ages using the pdfs, but did not address ΔR and the uncertainty in ΔR. We have developed an online application for performing these calculations for known-age, paired marine and terrestrial 14C dates and U-Th dated corals. This article briefly discusses methods that have been used for calculating ΔR and the uncertainty and describes the online program deltar, which is available free of charge.
We conducted a retrospective study of the appropriateness of antimicrobial agents prescribed on discharge from an acute care hospital. Seventy percent of discharge antibiotics were inappropriate in antibiotic drug choice, dose, or duration. Our findings suggest there is a significant need for antimicrobial stewardship at transitions in care.
This investigation examined the relationship between teachers’ beliefs and their preferences for classroom interventions for behaviours consistent with attention-deficit/hyperactivity disorder (ADHD). Teacher ratings of intervention acceptability, effectiveness, and rate of change were compared across United States and New Zealand samples. Beliefs examined were personal teaching efficacy, general teaching efficacy, and pupil control ideology (PCI). Samples were compared regarding their preferences for the daily report card, response cost technique, classroom lottery, and medication as classroom strategies for managing ADHD-related behavioural concerns. Data were analysed using general linear modelling techniques, and an interaction was demonstrated between ADHD intervention x PCI x nationality. Differences were observed for ADHD interventions across samples based upon pupil control orientations. Implications for educators and their classroom practices are discussed.
A model is proposed for predicting the presence of cumulative nonlinear distortions in the acoustic waveforms produced by high-speed jet flows. The model relies on the conventional definition of the acoustic shock formation distance and employs an effective Gol’dberg number
for diverging acoustic waves. The latter properly accounts for spherical spreading, whereas the classical Gol’dberg number
is restricted to plane wave applications. Scaling laws are then derived to account for the effects imposed by jet exit conditions of practical interest and includes Mach number, temperature ratio, Strouhal number and an absolute observer distance relative to a broadband Gaussian source. Surveys of the acoustic pressure produced by a laboratory-scale, shock-free and unheated Mach 3 jet are used to support findings of the model. Acoustic waveforms are acquired on a two-dimensional grid extending out to 145 nozzle diameters from the jet exit plane. Various statistical metrics are employed to examine the degree of local and cumulative nonlinearity in the measured waveforms and their temporal derivatives. This includes a wave steepening factor (WSF), skewness, kurtosis and the normalized quadrature spectral density. The analysed data are shown to collapse reasonably well along rays emanating from the post-potential-core region of the jet. An application of the generalized Burgers equation is used to demonstrate the effect of cumulative nonlinear distortion on an arbitrary acoustic waveform produced by a high-convective-Mach-number supersonic jet. It is advocated that cumulative nonlinear distortion effects during far-field sound propagation are too subtle in this range-restricted environment and over the region covered, which may be true for other laboratory-scale jet noise facilities.
Many patients treated for head and neck cancer require nutritional support, which is often delivered using a gastrostomy tube. It is difficult to predict which patients will retain their gastrostomy tube in the long term. This study aimed to identify the factors which affect the duration of gastrostomy tube retention.
In this retrospective study, 151 consecutive patients from one centre were audited. All patients had a mucosal tumour of the head and neck, and underwent gastrostomy tube insertion between 2003 and 2007.
There were near-complete data sets for 132 patients. The gastrostomy tube was retained in survivors (n = 66) for a mean of 21.3 months and in non-survivors (n = 66) for 11.9 months. Univariate analysis showed that co-morbidity was the only factor which significantly increased duration of gastrostomy tube retention in survivors (p = 0.041).
Co-morbidity alone was associated with a significant increase in gastrostomy tube retention. It is suggested that co-morbidity be included as a variable in future relevant research. Co-morbidity should also be considered when counselling patients about their long-term function following cancer treatment. Gastrostomy tube retention is likely to be affected by many factors, with few single variables having importance independently.
The Cumberland Infirmary, Carlisle, serves a largely remote, rural population of 330 000. The aim of this study was to report the treatment and survival figures for patients treated for laryngeal cancer at this centre.
The study included 209 consecutive patients with squamous cell carcinoma of the larynx diagnosed between 1996 and 2010 at the Cumberland Infirmary.
Disease-specific survival was 100 per cent for stage one, 76 per cent for stage two, 87 per cent for stage three and 46 per cent for stage four. In total, 76 patients (36 per cent) had a laryngectomy, either as primary treatment or as a salvage procedure.
Our tumour-specific survival rate was very high, and this success may be due in part to high rates of surgical intervention. Survival data compared favourably with other centres, despite less radical radiotherapy regimes. Laryngeal cancer can be managed effectively in a small, relatively remote, multidisciplinary team setting.
Infectious mononucleosis is a clinical manifestation of primary Epstein–Barr virus infection. It is unknown whether genetic factors contribute to risk. To assess heritability, we compared disease concordance in monozygotic to dizygotic twin pairs from the population-based California Twin Program and assessed the risk to initially unaffected co-twins. One member of 611 and both members of 58 twin pairs reported a history of infectious mononucleosis. Pairwise concordance in monozygotic and dizygotic pairs was respectively 12·1% [standard error (s.e.)=1·9%] and 6·1% (s.e.=1·2%). The relative risk (hazard ratio) of monozygotic compared to dizygotic unaffected co-twins of cases was 1·9 [95% confidence interval (CI) 1·1–3·4, P=0·03], over the follow-up period. When the analysis was restricted to same-sex twin pairs, that estimate was 2·5 (95% CI 1·2–5·3, P=0·02). The results are compatible with a heritable contribution to the risk of infectious mononucleosis.
Staphylococcus aureus is a leading cause of infections in deployed service members. Based on a molecular epidemiological study of 182 MRSA isolates from patients in three U.S. Army combat support hospitals in separate regions in Iraq, USA300 clone was the most predominant (80%) pulsotype. This finding suggested that strain carriage from the home country by military personnel is epidemiologically more important than local acquisition.
Stability of aminoglycoside resistance has been investigated in 20 strains of Staphylococcus aureus resistant to gentamicin (16 strains were also resistant to methicillin). In view of previous reports that incubation at elevated temperatures can hasten the loss of unstable antibiotic resistance, we passaged strains daily in a liquid medium for 24 days at 43 °C. The nine strains which were resistant to neomycin kept their aminoglycoside resistance virtually intact, whereas most of the other 11 strains (sensitive to neomycin) lost almost all their resistance to gentamicin and kanamycin after 5 days. It thus appears that the stability of aminoglycoside resistances in Staph. aureus is closely linked to the resistance of the strains to neomycin. This finding has important possible consequences in terms of the advisability of the clinical usage of preparations containing neomycin or framycetin for topical application and bowel sterilization.
Fatigue syndromes and irritable bowel syndrome (IBS) often occur together. Explanations include being different manifestations of the same condition and simply sharing some symptoms.
A matched case-control study in UK primary care, using data collected prospectively in the General Practice Research Database (GPRD). The main outcome measures were: health-care utilization, specific symptoms and diagnoses. Risk markers were divided into distant (from 3 years to 1 year before diagnosis) and recent (1 year before diagnosis).
A total of 4388 patients with any fatigue syndrome were matched to two groups of patients: those attending for IBS and those attending for another reason. Infections were specific risk markers for both syndromes, with viral infections being a risk marker for a fatigue syndrome [odds ratios (ORs) 2.3–6.3], with a higher risk closer to onset, and gastroenteritis a risk for IBS (OR 1.47, compared to a fatigue syndrome). Chronic fatigue syndrome (CFS) shared more distant risk markers with IBS than other fatigue syndromes, particularly other symptom-based disorders (OR 3.8) and depressive disorders (OR 2.3), but depressive disorders were a greater risk for CFS than IBS (OR 2.4). Viral infections were more of a recent risk marker for CFS compared to IBS (OR 2.8), with gastroenteritis a greater risk for IBS (OR 2.4).
Both fatigue and irritable bowel syndromes share predisposing risk markers, but triggering risk markers differ. Fatigue syndromes are heterogeneous, with CFS sharing predisposing risks with IBS, suggesting a common predisposing pathophysiology.
We have obtained high resolution spectra of the pre-main sequence binary system KH 15D (V582 Mon) while the star is fully visible, fully occulted, and during several ingress and egress events over the course of five contiguous observing seasons. The Hα line profile is a standard probe of the magnetospheric accretion flows on young stars such as KH 15D. We use these time series data to map out the size of the magnetosphere and find that it changes size from one observing season to the next.
Mineralogy and Remote Sensing of Rocks, Soil, Dust, and Ices
P. R. Christensen, Planetary Exploration Laboratory Arizona State University Moeur Building 110D Tempe, AZ 85287, USA,
J. L. Bandfield, Arizona State University, MC 6305 Mars Space Flight Facility Tempe, AZ, USA,
A. D. Rogers, Department of Geosciences, SUNY at Stony Brook Stony Brook, NY 11794, USA,
Glotch R. T. D., Department of Geosciences, SUNY at Stony Brook Stony Brook, NY 11794, USA,
V. E. Hamilton, Hawaii Institute of Geophysics & Planetology, University of Hawaii, 1680 East-West Road, Honolulu, HI 96822, USA,
S. W. Ruff, Mars Space Flight Facility Arizona State University Moeur Building, Room 131 Tempe, AZ 85287-6305, USA,
M. B. Wyatt, Brown University, Department of Geological Science, 324 Brook Street Providence, RI 02912-1846, USA
The Thermal Emission Spectrometer (TES) on Mars Global Surveyor (MGS) mapped the surface, atmosphere, and polar caps of Mars from 1997 through 2006. TES provided the first global mineral maps of Mars, and showed that the surface is dominated by primary volcanic minerals (plagioclase feldspar, pyroxene, and olivine) along with high-silica, poorly crystalline materials. Differences in the abundances of these minerals were initially grouped into two broad compositional categories that correspond to basalt and basaltic andesite. Additional analysis has identified four surface compositional groups that are spatially coherent, revealing variations in the composition of the primary crust-forming magmas through time. In general, plagioclase, high-Ca clinopyroxene, and high-silica phases are the dominant mineral groups for most regions, with lesser amounts of orthopyroxene, olivine, and pigeonite. One of the fundamental results from the TES investigation was the identification of several large deposits of crystalline hematite, including those in Meridiani Planum, that were interpreted to indicate the presence of liquid water for extended periods of time. This interpretation led to the selection of Meridiani as the target for the Opportunity rover, the first time that a planetary landing site was selected on the basis of mineralogic information. Aqueous weathering may have formed some of the high-silica phases seen in TES spectra at high latitudes, and the Mars Express Observatoire pour la Minéralogie, l'Eau, les Glaces et l'Activité (OMEGA) spectrometer has detected phyllosilicates and sulfates, typically formed by aqueous weathering and deposition, in several locations.
Aim: To compare voice performance following Bioplastique™ injection with that following Isshiki thyroplasty.
Measures: A 12 item, self-reported voice performance questionnaire was completed and observer-rated perceptual voice analysis scores were also measured, before and after Bioplastique injection, for 14 patients. Results were compared with our previously reported outcomes for 28 thyroplasty patients.
Results: Only 14 of 30 patients had complete datasets. For these patients, the mean pre-operative voice performance questionnaire score improved significantly, from 40.3 to 18.9 (p=0.002, Wilcoxon test). All perceptual analysis parameters showed significant improvement. These results compare favourably with the thyroplasty cohort (mean voice performance questionnaire score: pre-operative 35; post-operative 18; p<0.001). One Bioplastique patient developed contralateral paresis, requiring partial removal of the material 18 months later. Two thyroplasty patients experienced complications and three required revision.
Conclusions: Both Bioplastique injection and Isshiki thyroplasty resulted in a significant improvement in both subjective and perceptual voice performance. Our data suggest that the effect size of the two interventions is approximately similar (in nonrandomised cohorts of surviving patients). As in many similar studies, the incomplete follow-up data reflect severe comorbidity. Bioplastique injection is a quicker procedure associated with fewer complications, and thus appears superior to framework surgery in patients with limited life expectancy.
The taxonomy and phylogenetic relationships of fish trypanosomes are uncertain. A collection of 22 cloned trypanosome isolates from 14 species of European freshwater fish and 1 species of African freshwater fish were examined by molecular phylogenetic analysis. The small subunit ribosomal RNA (ssu rRNA) genes of 8 clones were sequenced and compared with ssu rRNA gene sequences from a wider selection of vertebrate trypanosome isolates by phylogenetic analysis. All trypanosomes from freshwater fish fell in a single clade, subdivided into 3 groups. This clade sits within a larger, robust clade containing trypanosomes from marine fish and various amphibious vertebrates. All 22 trypanosome clones were analysed by random amplification of polymorphic DNA. The resulting dendrogram shows 3 groups, which are congruent with the groups identified in the ssu rRNA gene phylogeny. Two of the groups contain the majority of trypanosome isolates and within-group variation is slight. These groups do not separate purported trypanosome species distinguished by morphology or host origin, and thus these criteria do not appear to be reliable guides to genetic relationships among fish trypanosomes. However, we suggest that the 2 groups themselves may represent different species of fish trypanosomes. The polymorphic DNA markers we have identified will facilitate future comparisons of the biology of these 2 groups of fish trypanosomes.
We present preliminary analysis of new HST observations of the transiting extrasolar planet HD 209458b. Photometric observations were obtained with the Fine Guidance Sensor (FGS) on the Hubble Space Telescope (HST), providing milli-mag precision and high time resolution (40 Hz). The FGS photometry allows us to derive precise stellar/orbital parameters (ephemeris, inclination, limb darkening) and planetary radius, and also allows a search for the presence of planetary rings and satellites. We discuss preliminary results and two approaches to modelling the observations.
Woody plant encroachment restricts forage production and capacity to produce grazing livestock. Biophysical plant growth simulation and economic simulation were used to evaluate a prescribed burning range management technique. Modeling systems incorporated management practices and costs, historical climate data, vegetation and soil inventories, livestock production data, and historical regional livestock prices. The process compared baseline non-treatment return estimates to expected change in livestock returns resulting from prescribed burning. Stochastic analyses of production and price variability produced estimates of greater net returns resulting from use of prescribed burning relative to the baseline.
Background. Verbal working memory (WM), which relies on intact functioning of frontostriatal circuits, has been suggested as a cognitive domain that is preferentially affected in HIV-1 infection. Although several studies have found WM impairments in HIV-1 infected patients, Baddeley's classic WM model has not been studied extensively in this population.
Methods. We used two cognitive neuropsychological approaches to examine verbal WM deficits in 18 HIV-1 seronegative, 16 HIV-1 asymptomatic, and 20 HIV-1 symptomatic patients. First, based on Baddeley's WM model of the Phonological Loop, we used the phonological similarity effect and the irrelevant speech effect to evaluate each individual's phonological store, and the word-length effect and the articulatory suppression effect to evaluate the articulatory control process. Secondly, an individual differences approach, which focuses on the capacity limitation of the WM system and potentially integrates the functions of Baddeley's Central Executive component with the Phonological Loop, was adopted. We evaluated each patient's simultaneous storage and processing of auditory material using the Verbal Memory Span test.
Results. The HIV-1 symptomatic individuals, but not the HIV-1 asymptomatic subjects, demonstrated impaired short-term storage of verbal material in the phonological store on Baddeley's measures. Although the HIV-1 asymptomatic and symptomatic subjects demonstrated intact rehearsal of speech-based material in the articulatory control process, both groups demonstrated impairment on the Verbal Memory Span test.
Conclusions. These findings suggest that deficits in simultaneous short-term storage and processing occur during both early and later stages of HIV-1 infection.