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Objectives: The aim of this study was to identify whether the three main primary progressive aphasia (PPA) variants would show differential profiles on measures of visuospatial cognition. We hypothesized that the logopenic variant would have the most difficulty across tasks requiring visuospatial and visual memory abilities. Methods: PPA patients (n=156), diagnosed using current criteria, and controls were tested on a battery of tests tapping different aspects of visuospatial cognition. We compared the groups on an overall visuospatial factor; construction, immediate recall, delayed recall, and executive functioning composites; and on individual tests. Cross-sectional and longitudinal comparisons were made, adjusted for disease severity, age, and education. Results: The logopenic variant had significantly lower scores on the visuospatial factor and the most impaired scores on all composites. The nonfluent variant had significant difficulty on all visuospatial composites except the delayed recall, which differentiated them from the logopenic variant. In contrast, the semantic variants performed poorly only on delayed recall of visual information. The logopenic and nonfluent variants showed decline in figure copying performance over time, whereas in the semantic variant, this skill was remarkably preserved. Conclusions: This extensive examination of performance on visuospatial tasks in the PPA variants solidifies some previous findings, for example, delayed recall of visual stimuli adds value in differential diagnosis between logopenic variant PPA and nonfluent variant PPA variants, and illuminates the possibility of common mechanisms that underlie both linguistic and non-linguistic deficits in the variants. Furthermore, this is the first study that has investigated visuospatial functioning over time in the PPA variants. (JINS, 2018, 24, 259–268)
Astronomical light echoes, the time-dependent light scattered by dust in the vicinity of varying objects, have been recognized for over a century. Initially, their utility was thought to be confined to mapping out the three-dimensional distribution of interstellar dust. Recently, the discovery of spectroscopically useful light echoes around centuries-old supernovae in the Milky Way and the Large Magellanic Cloud has opened up new scientific opportunities to exploit light echoes.
In this review, we describe the history of light echoes in the local Universe and cover the many new developments in both the observation of light echoes and the interpretation of the light scattered from them. Among other benefits, we highlight our new ability to classify outbursting objects spectroscopically, view them from multiple perspectives, obtain a spectroscopic time series of the outburst, and establish accurate distances to the source event. We also describe the broader range of variable objects with properties that may be better understood from light-echo observations. Finally, we discuss the prospects of new light-echo techniques not yet realized in practice.
Light echoes, light from a variable source scattered off dust, have been observed for over a century. The recent discovery of light echoes around centuries-old supernovae in the Milky Way and the Large Magellanic Cloud have allowed the spectroscopic characterization of these events, even without contemporaneous photometry and spectroscopy using modern instrumentation. Here we review the recent scientific advances using light echoes of ancient and historic transients, and focus on our latest work on SN 1987A's and Eta Carinae's light echoes.
Clostridium difficile spores persist in hospital environments for an extended period. We evaluated whether admission to a room previously occupied by a patient with C. difficile infection (CDI) increased the risk of acquiring CDI.
Retrospective cohort study.
Medical intensive care unit (ICU) at a tertiary care hospital.
Patients admitted from January 1, 2005, through June 30, 2006, were evaluated for a diagnosis of CDI 48 hours after ICU admission and within 30 days after ICU discharge. Medical, ICU, and pharmacy records were reviewed for other CDI risk factors. Admitted patients who did develop CDI were compared with admitted patients who did not.
Among 1,844 patients admitted to the ICU, 134 CDI cases were identified. After exclusions, 1,770 admitted patients remained for analysis. Of the patients who acquired CDI after admission to the ICU, 4.6% had a prior occupant without CDI, whereas 11.0% had a prior occupant with CDI (P = .002). The effect of room on CDI acquisition remained a significant risk factor (P = .008) when Kaplan-Meier curves were used. The prior occupant's CDI status remained significant (P = .01; hazard ratio, 2.35) when controlling for the current patient's age, Acute Physiology and Chronic Health Evaluation III score, exposure to proton pump inhibitors, and antibiotic use.
A prior room occupant with CDI is a significant risk factor for CDI acquisition, independent of established CDI risk factors. These findings have implications for room placement and hospital design.
We present BV photometry and the results of a search for stellar variability in the Galactic globular cluster M 69. The resulting color–magnitude diagram shows significant contamination by field stars. In our variability search we found 62 variable stars, 54 of which were new discoveries.
The structure of prehnite Ca2Al(AlSi3O10)(OH)2, including H positions, has been determined by a combination of single-crystal X-ray diffraction and neutron powder diffraction on four natural samples. The symmetry of the average structure with Al/Si disordered at the T2 siteis Pncm. However, for four of the crystals studied, numerous violations of the n- and c-glide reflection conditions indicate lower symmetry corresponding to space groups P2cm and P2/n and Al-Si ordered structures, possibly as domains of different symmetries and ordering within a single crystal. Time-of-flight neutron powder diffraction was carried out on a sample from Mali at 293 K and 2 K. The structure was refined in space group Pncm by Rietveld analysis. Although it was not possible to locate the missing H using the 293 K neutron data, these data were used to refine the H position located approximately by single-crystal XRD and to refine Uiso. For the 2 K neutron powder diffraction data, H was located directly by difference-Fourier synthesis and its refined position found to be in close agreement with that obtained by the combined XRD/neutron 293 K dataset.
The crystal structure of seeligerite, Pb3IO4Cl3, from the San Rafael mine, Sierra Gorda, Chile, was solved in the space group Cmm2, and refined to R = 3.07%. The unit-cell parameters are: a = 7.971(2), b = 7.976(2), c = 27.341(5) Å, V = 1738.3(6) Å3 and Z = 8. The crystal structure consists of a stacking sequence along  of square-net layers of O atoms and square-net layers of Cl atoms with Pb+ and I+ cations located in the voids of the packing. As is typical of cations with a stereoactive lone-pair of electrons, Pb2+ and I5+ adopt strongly-asymmetrical configurations. Pb2+ cations occur in a variety of coordination polyhedra, ranging from anticubes and monocapped anticubes to pyramidal ‘one-sided’ coordinations. I5+ is coordinated by a square of four oxygen atoms: I1 and I3 exhibit a ‘one-sided’ coordination, whereas I2 has square-planar coordination.
The TEM investigation has revealed additional superlattice reflections (which were not registered by X-ray diffraction (XRD)) in the hk0 diffraction pattern of seeligerite based upon a 0.158 Å-1 square net, which can be interpreted as arising from a 20-cation super-sheet motif (12.6 Å x 12.6 Å), likely related to a further level of Pb-I order superimposed upon the 8-site motif identified by XRD.
The meeting started at 16h00. The president welcomed the 24 participants to the business meeting of Commission 27. After the approval of the agenda, she gave an overview of the activities of Commission 27 of the past three years.
Cryptosporidium has become increasingly recognized as a pathogen responsible for outbreaks of diarrhoeal illness in both immunocompetent and immunocompromised persons. In August 2001, an Illinois hospital reported a cryptosporidiosis cluster potentially linked to a local waterpark. There were 358 case-patients identified. We conducted community-based and waterpark-based case-control studies to examine potential sources of the outbreak. We collected stool specimens from ill persons and pool water samples for microscopy and molecular analysis. Laboratory-confirmed case-patients (n=77) were more likely to have attended the waterpark [odds ratio (OR) 16·0, 95% confidence interval (CI) 3·8–66·8], had pool water in the mouth (OR 6·0, 95% CI 1·3–26·8), and swallowed pool water (OR 4·5, 95% CI 1·5–13·3) than age-matched controls. Cryptosporidium was found in stool specimens and pool water samples. The chlorine resistance of oocysts, frequent swimming exposures, high bather densities, heavy usage by diaper-aged children, and increased recognition and reporting of outbreaks are likely to have contributed to the increasing trend in number of swimming pool-associated outbreaks of cryptosporidiosis. Recommendations for disease prevention include alteration of pool design to separate toddler pool filtration systems from other pools. Implementation of education programmes could reduce the risk of faecal contamination and disease transmission.
The octahedral-framework mineral bernalite, Fe(OH)3, provides a rare opportunity to examine directly the effects of a vacant A site upon the physical properties of perovskite-like structures. Here, we report the effect upon compressibility. Bernalite has been reported previously as having space group Immm (Birch et al., 1993), but numerous reflections violating I-centering were observed in the present study. A case is presented for bernalite having orthorhombic space group Pmmn. Lattice parameters were refined using the Le Bail method for a metrically tetragonal cell and their variation with pressure at room temperature was determined from 17 measurements at pressures from 10–4 to 9.3 GPa using synchrotron X-ray powder diffraction. No discontinuities in the compression curves of lattice parameters were observed. Fitting to a second-order Birch-Murnaghan equation-of-state (KT0' = 4) gives V0 = 438.51±0.06 Å3 and KT0 = 78.2±0.4 GPa. Second-order fits of (a/a0)3 and (c/c0)3 give elastic moduli KT0a = 82.0(6) GPa and KT0c = 71.6(4) GPa: the shorter cation–cation distance is the more compressible. These values are very close to those of stottite, FeGe(OH)6, which has tilt system a+a+c–. The difference in the elastic moduli KT0a and KT0c of bernalite and their close similarity to the stottite values support the revised Pmmn structure (tilt system a+b+c–) for bernalite proposed here. The compressional anisotropy observed in bernalite may reflect its highly anisotropic and directional H-bonding topology.
We present the first results from our next-generation microlensing survey, the SuperMACHO project. We are using the CTIO 4m Blanco telescope and the MOSAIC imager to carry out a search for microlensing toward the Large Magellanic Cloud (LMC). We plan to ascertain the nature of the population responsible for the excess microlensing rate seen by the MACHO project. Our observing strategy is optimized to measure the differential microlensing rate across the face of the LMC. We find this derivative to be relatively insensitive to the details of the LMC's internal structure but a strong discriminant between Galactic halo and LMC self lensing. In December 2003 we completed our third year of survey operations. 2003 also marked the first year of real-time microlensing alerts and photometric and spectroscopic followup. We have extracted several dozen microlensing candidates, and we present some preliminary light curves and related information. Similar to the MACHO project, we find SNe behind the LMC to be a significant contaminant - this background has not been completely removed from our current single-color candidate sample. Our follow-up strategy is optimized to discriminate between SNe and true microlensing.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html
To evaluate the consumption of added fats and oils across the European centres and countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC).
Design and setting:
24-Hour dietary recalls were collected by means of standardised computer-guided interviews in 27 redefined EPIC centres across 10 European countries.
From an initial number of 36 900 subjects, single dietary recalls from 22 924 women and 13 031 men in the age range of 35–74 years were included.
Mean daily intake of added fats and oils varied between 16.2 g (Varese, Italy) and 41.1 g (Malmö, Sweden) in women and between 24.7 g (Ragusa, Italy) and 66.0 g (Potsdam, Germany) in men. Total mean lipid intake by consumption of added fats and oils, including those used for sauce preparation, ranged between 18.3 (Norway) and 37.2 g day−1 (Greece) in women and 28.4 (Heidelberg, Germany) and 51.2 g day−1 (Greece) in men. The Mediterranean EPIC centres with high olive oil consumption combined with low animal fat intake contrasted with the central and northern European centres where fewer vegetable oils, more animal fats and a high proportion of margarine were consumed. The consumption of added fats and oils of animal origin was highest in the German EPIC centres, followed by the French. The contribution of added fats and oils to total energy intake ranged from 8% in Norway to 22% in Greece.
The results demonstrate a high variation in dietary intake of added fats and oils in EPIC, providing a good opportunity to elucidate the role of dietary fats in cancer aetiology.
The commissioning and operation of apparatus for neutron diffraction at simultaneous high temperatures and pressures is reported. The basic design is based on the Paris-Edinburgh cell using opposed anvils, with internal heating. Temperature is measured using neutron radiography. The apparatus has been shown in both on-line and off-line tests to operate to a pressure of 7 GPa and temperature of 1700°C. The apparatus has been used in a neutron diffraction study of the crystal structure of deuterated brucite, and results for 520°C and 5.15 GPa are presented. The diffraction data that can be obtained from the apparatus are of comparable quality to previous high-pressure studies at ambient temperatures, and are clearly good enough for Rietveld refinement analysis to give structural data of reasonable quality.