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Anisocotyly, the unequal development of cotyledons post germination, is a unique trait observed only in Old World Gesneriaceae (Lamiales). New World Gesneriaceae have isocotylous seedlings. In both Old and New World Gesneriaceae, cotyledons initially grow equally for a short period just after germination. In the New World species, both cotyledons cease their growth at the same time early on, whereas in Old World species one cotyledon continues to expand to become a macrocotyledon while the other withers away. In this study, cotyledon growth was observed in two European Old World Gesneriaceae: Haberlea rhodopensis and Ramonda myconi. The results were compared with those for the typical anisocotylous species Streptocarpus rexii and the typical isocotylous species Corytoplectus speciosus. We found that the cotyledon growth patterns in Haberlea rhodopensis and Ramonda myconi were intermediate between the typical anisocotylous or isocotylous species. Haberlea rhodopensis and Ramonda myconi showed irregular growth patterns, with some plants being slightly anisocotylous but most being isocotylous. The developmental basis for the residual anisocotyly, the extended basal meristem activity in the macrocotyledon, appeared to be identical in the European species to that in the typical Old World Streptocarpus rexii but weakly expressed, rare and terminated early. In conclusion, European Gesneriaceae retain a reduced anisocotylous growth that may be linked to their early plumule development.
As part of ongoing molecular phylogenetic work on the large Gesneriaceae genus Cyrtandra, new insights into the taxonomy and relationships of the Cyrtandra of Japan, Taiwan and Batan Island in the northern Philippines have emerged. Cyrtandra umbellifera is confirmed as a species with a distribution that includes both Taiwan and Batan Island. Cyrtandra yaeyamae is found to be distinct from the widespread C. cumingii, with a distribution that includes both the Ryukyu Islands in Japan and Batan Island.
Towards a comprehensive revision of Gesneriaceae in Sri Lanka, 12 names are here typified, of which 11 are lectotypifications, including one second-step lectotypification, and the other is a neotypification.
Two new species of Oreocharis, O. tribracteata and O. rufescens, are described and a key to the species in Vietnam is provided. The new species have distinct features not previously, or rarely, observed in the genus, both showing the partial fusion of the calyx lobes into a tube, and the presence of three bracts in Oreocharis tribracteata.
The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
In 2015, Denmark launched an automated surveillance system for hospital-acquired infections, the Hospital-Acquired Infections Database (HAIBA).
To describe the algorithm used in HAIBA, to determine its concordance with point prevalence surveys (PPSs), and to present trends for hospital-acquired bacteremia
Private and public hospitals in Denmark
A hospital-acquired bacteremia case was defined as at least 1 positive blood culture with at least 1 pathogen (bacterium or fungus) taken between 48 hours after admission and 48 hours after discharge, using the Danish Microbiology Database and the Danish National Patient Registry. PPSs performed in 2012 and 2013 were used for comparison.
National trends showed an increase in HA bacteremia cases between 2010 and 2014. Incidence was higher for men than women (9.6 vs 5.4 per 10,000 risk days) and was highest for those aged 61–80 years (9.5 per 10,000 risk days). The median daily prevalence was 3.1% (range, 2.1%–4.7%). Regional incidence varied from 6.1 to 8.1 per 10,000 risk days. The microorganisms identified were typical for HA bacteremia. Comparison of HAIBA with PPS showed a sensitivity of 36% and a specificity of 99%. HAIBA was less sensitive for patients in hematology departments and intensive care units. Excluding these departments improved the sensitivity of HAIBA to 44%.
Although the estimated sensitivity of HAIBA compared with PPS is low, a PPS is not a gold standard. Given the many advantages of automated surveillance, HAIBA allows monitoring of HA bacteremia across the healthcare system, supports prioritizing preventive measures, and holds promise for evaluating interventions.
Strong absorption lines in quasar spectra primarily probe low-mass galaxies and detecting these in emission has previously been difficult. Dedicated surveys for the host galaxies of damped Lyman-α (DLA) systems have often resulted in non-detections and upper limits. Targeting the most metal-rich absorbers has proven to be a viable method, because these galaxies are brighter. By combining DLA metallicities and deriving host galaxy stellar masses, we find that metal-rich DLAs (with >10% solar metallicity) and their host galaxies follow the same redshift-dependent scaling relation between stellar mass and metallicity as luminosity-selected galaxies. We derive a prediction for an absorber galaxy mass that depends on the DLA metallicity.
The aim of this study was to determine the genetic background of longitudinal residual feed intake (RFI) and BW gain in farmed mink using random regression methods considering heterogeneous residual variances. The individual BW was measured every 3 weeks from 63 to 210 days of age for 2139 male+female pairs of juvenile mink during the growing-furring period. Cumulative feed intake was calculated six times with 3-week intervals based on daily feed consumption between weighing’s from 105 to 210 days of age. Genetic parameters for RFI and BW gain in males and females were obtained using univariate random regression with Legendre polynomials containing an animal genetic effect and permanent environmental effect of litter along with heterogeneous residual variances. Heritability estimates for RFI increased with age from 0.18 (0.03, posterior standard deviation (PSD)) at 105 days of age to 0.49 (0.03, PSD) and 0.46 (0.03, PSD) at 210 days of age in male and female mink, respectively. The heritability estimates for BW gain increased with age and had moderate to high range for males (0.33 (0.02, PSD) to 0.84 (0.02, PSD)) and females (0.35 (0.03, PSD) to 0.85 (0.02, PSD)). RFI estimates during the growing period (105 to 126 days of age) showed high positive genetic correlations with the pelting RFI (210 days of age) in male (0.86 to 0.97) and female (0.92 to 0.98). However, phenotypic correlations were lower from 0.47 to 0.76 in males and 0.61 to 0.75 in females. Furthermore, BW records in the growing period (63 to 126 days of age) had moderate (male: 0.39, female: 0.53) to high (male: 0.87, female: 0.94) genetic correlations with pelting BW (210 days of age). The result of current study showed that RFI and BW in mink are highly heritable, especially at the late furring period, suggesting potential for large genetic gains for these traits. The genetic correlations suggested that substantial genetic gain can be obtained by only considering the RFI estimate and BW at pelting, however, lower genetic correlations than unity indicate that extra genetic gain can be obtained by including estimates of these traits during the growing period. This study suggests random regression methods are suitable for analysing feed efficiency and BW gain; and genetic selection for RFI in mink is promising.
Recently, the usage of optical fiber coils has increased significantly, especially in the design of physic and chemical sensors. Therefore, it is important to test the theoretical current models developed to predict the power loss throughout optical fiber. In this paper a pioneer and popular model, the Marcuse model of power loss, was studied and evaluated for optical fiber coils of small radii. Power attenuation in a bent fiber data was collected using an Optical Time Domain Reflectometer (OTDR), and it was compared to the theoretical predictions of the Marcuse model. It was observed that the model predicts correctly the attenuation behavior for usual curvature radii, however, it fails to predict accurately the attenuation behavior for small curvature radii, underestimating considerably the actual power loss. Also, it has been observed that at small radii the power loss parameter 2α and the mode propagation constant of the wave guide β stop being constants and become functions of the optical path, particularly of the number of loops in the coil. It is possible that new mechanisms of light leaking are present, due to the extreme distortion of the modes configuration into the fiber at small radii. Those mechanisms cannot be described by a model that considers a power loss parameter 2α, and more specifically the mode propagation constant of the wave guide (β) as constants. Then it is important to develop other models where the previous parameters can be considered as functions of the optical path.
The oscillating piezoelectric field of a surface acoustic wave (SAW) is employed to transport photoexcited electrons and holes in GaAs nanowires (NWs) transferred to a SAW beam line on a LiNbO3 crystal. We show that carriers generated in the NW by a focused light spot can be acoustically transported to a second location, where they recombine emitting short light pulses. The results presented here demonstrate the high-frequency manipulation of carriers in NWs without the use of electrical contacts, which opens new perspectives for applications in opto-electronic devices operating at GHz frequencies.
Young people with self-experienced cognitive thought and perception deficits (basic symptoms) may present with an early initial prodromal state (EIPS) of psychosis in which most of the disability and neurobiological deficits of schizophrenia have not yet occurred.
To investigate the effects of an integrated psychological intervention (IPI), combining individual cognitive–behavioural therapy, group skills training, cognitive remediation and multifamily psychoeducation, on the prevention of psychosis in the EIPS.
A randomised controlled, multicentre, parallel group trial of 12 months of IPI v. supportive counselling (trial registration number: NCT00204087). Primary outcome was progression to psychosis at 12- and 24-month follow-up.
A total of 128 help-seeking out-patients in an EIPS were randomised. Integrated psychological intervention was superior to supportive counselling in preventing progression to psychosis at 12-month follow-up (3.2% v. 16.9%; P = 0.008) and at 24-month follow-up (6.3% v. 20.0%; P = 0.019).
Integrated psychological intervention appears effective in delaying the onset of psychosis over a 24-month time period in people in an EIPS.
Percutaneous tracheotomy (PT) is beneficial in decreasing dead space and reducing airway resistance when compared with intubation. Absolute contraindications include the need for an emergent airway or inability to intubate the patient. All current PT methods are based upon the Seldinger technique of dilators placed over a guidewire. It is recommended that PT be performed under simultaneous video bronchoscopy. Techinques for PT are: Ciaglia method (percutaneous dilating technique), Griggs technique (guidewire dilating forceps (GWDF) technique), Fantoni's technique (translaryngeal approach), and PercTwist (screw-action dilator). Two important issues specific to PT that may arise during the course of the procedure are accidental penetration of the endotracheal tube cuff with the introducer needle during initial puncture of the anterior tracheal wall and possible dislocation of the endotracheal tube. The most common immediate postoperative complication is bleeding. Long-term complications have been reported extensively in a number of studies and metaanalyses.
Individuals with body dysmorphic disorder (BDD) may have perceptual distortions for their appearance. Previous studies suggest imbalances in detailed relative to configural/holistic visual processing when viewing faces. No study has investigated the neural correlates of processing non-symptom-related stimuli. The objective of this study was to determine whether individuals with BDD have abnormal patterns of brain activation when viewing non-face/non-body object stimuli.
Fourteen medication-free participants with DSM-IV BDD and 14 healthy controls participated. We performed functional magnetic resonance imaging (fMRI) while participants matched photographs of houses that were unaltered, contained only high spatial frequency (HSF, high detail) information or only low spatial frequency (LSF, low detail) information. The primary outcome was group differences in blood oxygen level-dependent (BOLD) signal changes.
The BDD group showed lower activity in the parahippocampal gyrus, lingual gyrus and precuneus for LSF images. There were greater activations in medial prefrontal regions for HSF images, although no significant differences when compared to a low-level baseline. Greater symptom severity was associated with lower activity in the dorsal occipital cortex and ventrolateral prefrontal cortex for normal spatial frequency (NSF) and HSF images.
Individuals with BDD have abnormal brain activation patterns when viewing objects. Hypoactivity in visual association areas for configural and holistic (low detail) elements and abnormal allocation of prefrontal systems for details are consistent with a model of imbalances in global versus local processing. This may occur not only for appearance but also for general stimuli unrelated to their symptoms.
Nanometer sized gold patterns were produced with controlled spacings using the combination of a top-down (e-beam lithography) and a bottom-up (macromolecular chemistry) technique. Sub-10 nm nanoparticle arrays on silicon consisting of gold nano particles separated by micro meter spacings were fabricated with this approach. Using electron beam lithography, templates comprising of 150 nm to 1 μm sized trenches, holes and aperiodic patterns were made in an electron-beam resist. Block copolymer micelles were then patterned into this template by spincoating. The micelles acted as positioners for a nanometer sized gold precursor that is sequestered within its core. Subsequent removal of the resist layer left an array of Au loaded organic micelles ordered according to the pattern of the template. Exposure of this substrate to a hydrogen plasma removed the organic block copolymer and resulted in an array of sub-10 nm gold nanoparticles/nanoclusters with micron separations. The gold was then used as an anchor point for the tethering of functional molecules in order to localize fluorescent molecules.
The synthesis of spatially controlled Ge nanowires and nanoclusters by
Ge+ ion implantation in oxidized V-grooves on (001) Si
surfaces has been studied experimentally as well as theoretically. The
V-grooves were prepared by anisotropic wet chemical etching and thermal
oxidation. The SiO2-covered V-grooves were implanted with 70 keV
Ge+ ions up to a fluence of 1017 cm−2.
Ge accumulates within the SiO2 at the bottom of the V-groove,
which has been proven by analytical TEM (EDX-mapping). Theoretical studies
have shown that the Ge accumulation is caused by the V-groove geometry,
forward sputtering, and re-deposition. During subsequent annealing the
redistributed Ge forms a nanowire by precipitation, ripening and
coalescence. Kinetic lattice Monte Carlo simulations of the nanowire
formation process show growth instabilities and self-organization
Ion implantation, specified by parameters like ion energy, ion fluence, ion
flux and sub-strate temperature, has become a well-established tool to
synthesize buried low-dimensional nanostructures. In general, in ion beam
synthesis the evolution of nanostructures is determined by the competition
between ballistic and thermodynamic effects. A kinetic 3D lattice
Monte-Carlo model is introduced, which allows for a proper incorporation of
collisional mixing and phase separation within supersaturated
solid-solutions. It is shown, that for both the ballistically and
thermodynamically dominated regimes, the Gibbs-Thomson relation is the key
ingredient in understanding nanocluster evolution. Various aspects of
precipitate evolution during implantation, formation of ordered arrays of
nanophase domains by focused ion implantation and compound nanocluster
synthesis are discussed.
The precipitation of copper and nickel at grain boundaries in cast polycrystalline silicon is investigated. The metals are diffused into the specimens from a surface source between 800 – 1000 °C and the precipitation after cooling is studied by TEM. Copper precipitates in form of colonies containing hundreds of particles with a size between 5–6 nm. In the grain boundary they nucleate preferentially at dislocations and steps. The distribution and size of the precipitates depend on the cooling rate after the diffusion. Nickel forms only few large (micrometer size) plate-like or three dimensional precipitates at and near grain boundaries. The main features of the results and the differences between the two elements are explained under the assumption that the precipitation requires the transport of native point defects.