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Clostridioides difficile infection (CDI) remains a significant public health concern, resulting in excess morbidity, mortality, and costs. Additional insight into the burden of CDI in adults aged <65 years is needed.
A 6-year retrospective cohort study was conducted using data extracted from United States Veterans Health Administration electronic medical records.
Patients aged 18–64 years on January 1, 2011, were followed until incident CDI, death, loss-to-follow-up, or December 31, 2016. CDI was identified by a diagnosis code accompanied by metronidazole, vancomycin, or fidaxomicin therapy, or positive laboratory test. The clinical setting of CDI onset was defined according to 2017 SHEA-IDSA guidelines.
Of 1,073,900 patients, 10,534 had a CDI during follow-up. The overall incidence rate was 177 CDIs per 100,000 person years, rising steadily from 164 per 100,000 person years in 2011 to 189 per 100,000 person years in 2016. Those with a CDI were slightly older (55 vs 51 years) and sicker, with a higher baseline Charlson comorbidity index score (1.4 vs 0.5) than those without an infection. Nearly half (48%) of all incident CDIs were community associated, and this proportion rose from 41% in 2011 to 56% in 2016.
The findings from this large retrospective study indicate that CDI incidence, driven primarily by increasing community-associated infection, is rising among young and middle-aged adult Veterans with high service-related disability. The increasing burden of community associated CDI in this vulnerable population warrants attention. Future studies quantifying the economic and societal burden of CDI will inform decisions surrounding prevention strategies.
Solid solutions are pervasive in minerals and in industrial inorganic materials. The analyst is often called upon to provide qualitative and quantitative X-ray phase analysis for specimens containing solid solutions when all that is available are Powder Diffraction File (PDF) data or commercial standards for the end members. In an earlier paper (1) we presented several examples of substantial errors in accuracy of quantitative analysis that can arise when the crystallinity and composition of the analyte standard do not match those of the analyte in the sample of interest. We recommended that to obtain more accurate quantitative analyses, one should determine the analyte composition (e.g., from XRF on grains seen in a SEM or from comparison of cell parameters with those of the end members) and synthesize an analyte standard with this composition and with a crystallinity approximating that of the analyte (e.g., as determined from peak breadth or α1/ α2 splitting).
In 1921, when Sir Ernest Shackleton was planning his circum-Antarctic expedition on the R.Y.S. Quest, he was eager to appoint a suitably qualified young person as a cabin boy or deck hand. He expressed great admiration for the Boy Scout Movement and its founder, Sir Robert Baden-Powell. Discussions between them led to Shackleton advertising for a Boy Scout to accompany him on the expedition, believing that the experience would greatly benefit the youngster's character, as well as providing much positive publicity for the expedition. He selected two young Scouts but, while much has been written about James Marr, no account has been written about the younger boy, Norman Mooney. This is because he was unable to cope with continuous seasickness and had to return home after only four weeks at sea. This account provides some little-known detail about Mooney and why he was selected, and about Shackleton's sensitive recruiting procedure.
The drafting, publishing and subsequent reproduction of Edward Wilson's evocative and sinisterly premonitory poem, The Barrier Silence, is examined. It was written in October 1911 for Part 3 of the South Polar Times (SPT), Vol. 3, prepared and ‘published’ at Robert Falcon Scott's British Antarctic (Terra Nova) Expedition hut at Cape Evans, Ross Island, shortly before Wilson, Scott and three other members set off on the ill-fated South Pole journey. Wilson contributed most of the illustrative material for all three volumes of the SPT, but this poem is the only written article attributed to him, although it is possible that he was also the author of an anonymous poem. Events that may have influenced Wilson to write his poem are also considered.
The Antarctic Treaty recognizes the outstanding scientific values of the Antarctic environment through the designation of Antarctic Specially Protected Areas (ASPAs) that have rigorous management plans specific to each site. Deception Island has the largest concentration of rare bryophyte species and communities in Antarctica, while also offering substantial opportunities for research in a range of scientific disciplines due to its volcanic nature. As a result, conflicts between research interests and conservation goals may arise. On the summit ridge of Caliente Hill severe trampling damage to the moss assemblages growing in association with localized geothermal activity was observed. The range of species affected included the entire known population of Schistidium deceptionense, an endemic moss known only from this site, as well as other very rare Antarctic mosses (Ditrichum ditrichoideum, Bryum orbiculatifolium, Bucklandiella subcrispipila, Pohlia wahlenbergii and Dicranella hookeri). A photomapping study was undertaken to characterize further the status of the site and monitor changes within it. Increased awareness, co-ordination of activities and a spatial zoning within the site could help mitigate damage from permitted activities. Nevertheless, prioritization of longer term conservation goals over short-term research interests may ultimately be necessary where local human impact cannot be managed by other means.
The derivation of a constitutive law to describe large-scale sea-ice deformation commonly uses the so-called “flow rule”. This method introduces a mathematically imposed relationship between shear strength and dilatation which is not based on physical postulates. In this note a more general procedure is described which uses the Reiner–Rivlin equation as a starting point. The method is illustrated by deriving a particular constitutive law and applying it to a simple problem of sea ice blown against a shoreline.
Light curves of quasars give information on time scales (hence limits on size of principal luminous source), and on phase of variation (hence evidence bearing on the distance of surrounding regions or shells).
For three months in 1970, NASA, Goddard Space Flight Center conducted an experiment to try and detect the motion of the Earth's pole of rotation by laser ranging to an Earth satellite. Two laser tracking stations were used, one at Goddard Space Flight Center and one near Seneca in New York State, 408 km away and on the same meridian as the Goddard station. The objective of the experiment was to precisely measure the orbital inclination of the Beacon Explore C spacecraft, on a daily basis and with a resolution of a few hours, to a few hundredths of an arc second by the simultaneous tracking of the spacecraft as it passed between the two stations. During the experiment over fifty thousand range measurements on over two hundred revolutions of the satellite were obtained and on fifty occasions the satellite was simultaneously tracked at both stations. The noise accuracy of the tracking varied between 20 and 60 cm during most of the experiment and the orbital inclination obtained from the measurements showed a systematic change of about 25 arc sec, due primarily (about 80%) to the gravitational perturbation of the orbit by the Sun and the Moon. Perturbations by solar radiation pressure and the solid-Earth tides appear to account for most of the remaining systematic changes in the inclination and from which it has been possible to derive a value of Love's number for the Earth as
A preliminary determination of the motion of the pole in the meridian containing the stations by subtracting the known perturbations (including tides) from the observed perturbation suggests that an accuracy of 3 to 5 m has been obtained, over periods of about 6 hr, during the latter part of the experiment. The experiment has also demonstrated that the present laser tracking systems are able to measure the chord distance between the two tracking stations with a repeatability of 25 to 30 cm.
The present analysis of the data is directed towards an improved extraction of the gravitational perturbations and an improved determination of the Love number k2.
A full account of the experiment and its results so far will be published elsewhere.
We previously reported an association between 5HTTLPR genotype and
outcome following cognitive–behavioural therapy (CBT) in child anxiety
(Cohort 1). Children homozygous for the low-expression short-allele
showed more positive outcomes. Other similar studies have produced mixed
results, with most reporting no association between genotype and CBT
To replicate the association between 5HTTLPR and CBT outcome in child
anxiety from the Genes for Treatment study (GxT Cohort 2,
n = 829).
Logistic and linear mixed effects models were used to examine the
relationship between 5HTTLPR and CBT outcomes. Mega-analyses using both
cohorts were performed.
There was no significant effect of 5HTTLPR on CBT outcomes in Cohort 2.
Mega-analyses identified a significant association between 5HTTLPR and
remission from all anxiety disorders at follow-up (odds ratio 0.45,
P = 0.014), but not primary anxiety disorder
The association between 5HTTLPR genotype and CBT outcome did not
replicate. Short-allele homozygotes showed more positive treatment
outcomes, but with small, non-significant effects. Future studies would
benefit from utilising whole genome approaches and large, homogenous
Laser tracking of the Lageos spacecraft has been used to derive the position of the Earth's pole of rotation at 5-day intervals during October, November and December 1976. The estimated precision of the results is 0.01 to 0.02 arcseconds in both x and y components, although the formal uncertainty is an order of magnitude better, and there is general agreement with the Bureau International de l'Heure smoothed pole path to about 0.02 arcseconds. Present orbit determination capability of Lageos is limited to about 25 cm rms fit to data over periods of 5 days and about 50 cm over 50 days. The present major sources of error in the perturbations of Lageos are Earth and ocean tides followed by the Earth's gravity field, and solar and Earth reflected radiation pressure. Ultimate accuracy for polar motion and Earth rotation from Lageos after improved modeling of the perturbing forces appears to be of order ± 5 cm for polar motion over a period of about 1 day and about ± 0.2 to ± 0.3 milliseconds in U.T. for periods up to 2 or 3 months.
Electrochemical reactions at both positive and negative electrodes in a nickel metal hydride (Ni-MH) battery during charge have been investigated by in situ neutron powder diffraction. Commercially available β-Ni(OH)2 and LaNi5-based powders were used in this experiment as positive and negative electrodes, respectively. Exchange of hydrogen by deuterium for the β-Ni(OH)2 electrode was achieved by ex situ cycling of the cell prior to in situ measurements. Neutron diffraction data collected in situ show that the largest amount of deuterium contained at the positive electrode is de-intercalated from the electrode with no phase transformation involved up to ∼100 mA h/g and, in addition, the 110 peak width for the positive electrode increases on charge. The negative electrode of composition MmNi3.6Al0.4Mn0.3Co0.7, where Mm = Mischmetal, exhibits a phase transformation to an intermediate hydride γ phase first and then to the β phase on charge. Unit cell dimensions and phase fractions have been investigated by Rietveld refinement of the crystal structure.
This presentation outlines disparities in the uptake of accident compensation entitlements by indigenous New Zealanders and a programme to prevent injury and improve outcomes/experience for Māori. ACC administers NZ's 24/7 no-fault accident compensation scheme which covers New Zealanders and visitors to NZ injured at work, home, play, in road crashes, or during treatment. Research has shown that disparities persist in injury outcomes/experience for NZ's indigenous population (Māori make-up 15% of the population and experience multiple disadvantage). This is inconsistent with the Government's commitment to Crown-Māori partnership.
Disparities findings persist for Māori included; higher rates of serious/fatal injuries on the roads, lower GP referral rates to medical/surgical specialists, found the claim process more complicated and ACC less helpful in their return to work and lower rates of employment participation following a serious injury.
ACC's 10 year vision of success; improved outcomes/experience for Māori clients and businesses, increased injury prevention effectiveness for Māori and improved ACC culture and capability in relation to Māori.
Over a three year period, the ACC Board considered a series of papers on disparities in the uptake of entitlements by Māori. In early 2013, the Board considered advice on the Scheme's and organisation's responsiveness to Māori and endorsed the need for significant improvements. We shall explore two phases. Phase 1 of ACC's Māori Programme aims to reduce disparities, build organisational capability and establish relationships. Initiatives include innovative solutions to improve employment participation of seriously injured Māori. Phase 2 builds new partnerships with indigenous organisations and embeds cultural-responsiveness into the organisation/system. Challenges include building genuine partnerships and sustaining the Programme in a changing organisational, social, political and economic context. Improving injury outcomes/experience for Māori is a long-term commitment. Programme success includes fewer fatal/serious injuries to Maori, better employment participation after injury, and new partnerships.
Retinal pigment epithelial cells of teleosts contain numerous melanosomes (pigment granules) that exhibit light-dependent motility. In light, melanosomes disperse out of the retinal pigment epithelium (RPE) cell body (CB) into long apical projections that interdigitate with rod photoreceptors, thus shielding the photoreceptors from bleaching. In darkness, melanosomes aggregate through the apical projections back into the CB. Previous research has demonstrated that melanosome motility in the RPE CB requires microtubules, but in the RPE apical projections, actin filaments are necessary and sufficient for motility. We used myosin S1 labeling and platinum replica shadowing of dissociated RPE cells to determine actin filament polarity in apical projections. Actin filament bundles within RPE apical projections are uniformly oriented with barbed ends toward the distal tips. Treatment of RPE cells with the tetravalent lectin, Concanavalin A, which has been shown to suppress cortical actin flow by crosslinking of cell-surface proteins, inhibited melanosome aggregation and stimulated ectopic filopodia formation but did not block melanosome dispersion. The polarity orientation of F-actin in apical projections suggests that a barbed-end directed myosin motor could effect dispersion of melanosomes from the CB into apical projections. Inhibition of aggregation, but not dispersion, by ConA confirms that different actin-dependent mechanisms control these two processes and suggests that melanosome aggregation is sensitive to treatments previously shown to disrupt actin cortical flow.
Significant new opportunities for astrophysics and cosmology have been identified at low radio frequencies. The Murchison Widefield Array is the first telescope in the southern hemisphere designed specifically to explore the low-frequency astronomical sky between 80 and 300 MHz with arcminute angular resolution and high survey efficiency. The telescope will enable new advances along four key science themes, including searching for redshifted 21-cm emission from the EoR in the early Universe; Galactic and extragalactic all-sky southern hemisphere surveys; time-domain astrophysics; and solar, heliospheric, and ionospheric science and space weather. The Murchison Widefield Array is located in Western Australia at the site of the planned Square Kilometre Array (SKA) low-band telescope and is the only low-frequency SKA precursor facility. In this paper, we review the performance properties of the Murchison Widefield Array and describe its primary scientific objectives.
Thin-film piezoelectric lead zirconate titanate (PZT) is one of the most efficient electromechanical coupling transducer materials currently available for microelectromechanical systems (MEMS). This article reviews piezoelectric MEMS (piezo MEMS) technologies using PZT thin films in radio frequency (RF) devices for communications and radar applications and in the emerging field of millimeter-scale robotics. The electromechanical material properties of thin-film PZT uniquely enable insect-inspired and insect-scale autonomous robots. Recent progress on large force and displacement actuators for robotic leg joints, compact and high torque ultrasonic motors, and bioinspired millimeter-scale flapping wing platforms will be presented. The use of thin-film PZT to achieve high performance and low-voltage RF MEMS switches, ultralow power consumption nanomechanical logic circuits, and high coupling and low loss resonators, filters, and transformers are also reviewed.