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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.
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.
By consistently connecting the chemical and spectrophotometric evolution of galaxies we are able to include the effect of dust absorption. The time and redshift evolution of the extinction is based on the evolution of the gas content and metallicity. We present our evolutionary synthesis models which include dust absorption to analyze the UV emission in various galaxy types. We are able to predict the extinction E(B-V) for different galaxy types as a function of redshift. We further use these models to explore the range of metallicities in normal and starbursting galaxies and the metallicity distribution of the stellar population. Comparing our model spectral energy distributions (SEDs) with templates from R. C. Kennicutt's (1992, ApJS 79, 255) and A. L. Kinney et al.'s (1996, ApJ, 467, 38) atlas we show the detailed agreement with integrated spectra of galaxies and point out the importance of aperture effects. Combined with a cosmological model we show the differences in the evolutionary and K-corrections by comparing models with and without dust.
Norovirus outbreaks occur frequently in Denmark and it can be difficult to establish whether apparently independent outbreaks have the same origin. Here we report on six outbreaks linked to frozen raspberries, investigated separately over a period of 3 months. Norovirus from stools were sequence-typed; including extended sequencing of 1138 bp encompassing the hypervariable P2 region of the capsid gene. Norovirus was detected in 27 stool samples. Genotyping showed genotype GI.Pb_GI.6 (polymerase/capsid) with 100% identical sequences. Samples from five outbreaks were furthermore identical over the variable capsid P2 region. In one outbreak at a hospital canteen, frozen raspberries was associated with illness by cohort investigation (relative risk 6·1, 95% confidence interval 3·2–11). Bags of raspberries suspected to be the source were positive for genogroup I and II noroviruses, one typable virus was genotype GI.6 (capsid). These molecular investigations showed that the apparently independent outbreaks were the result of one contamination event of frozen raspberries. The contaminated raspberries originated from a single producer in Serbia and were originally not considered to belong to the same batch. The outbreaks led to consultations and mutual visits between producers, investigators and authorities. Further, Danish legislation was changed to make heat-treatment of frozen raspberries compulsory in professional catering establishments.
We investigated an outbreak of gastroenteritis following a Christmas buffet served on 4–9 December 2012 to ~1300 hotel guests. More than 300 people were reported ill in initial interviews with hotel guests. To identify possible sources of infection we conducted a cohort investigation through which we identified 214 probable cases. Illness was associated with consumption of scrambled eggs (odds ratio 9·07, 95% confidence interval 5·20–15·84). Imported chives added fresh to the scrambled eggs were the suspected source of the outbreak but were unavailable for testing. Enterotoxigenic Escherichia coli (ETEC) infection was eventually confirmed in 40 hotel guests. This outbreak reinforces that ETEC should be considered in non-endemic countries when the clinical picture is consistent and common gastrointestinal pathogens are not found. Following this outbreak, the Norwegian Food Safety Authority recommended that imported fresh herbs should be heat-treated before use in commercial kitchens.
Most finite spatial point process models specified by a density are locally stable, implying that the Papangelou intensity is bounded by some integrable function β defined on the space for the points of the process. It is possible to superpose a locally stable spatial point process X with a complementary spatial point process Y to obtain a Poisson process X ⋃ Y with intensity function β. Underlying this is a bivariate spatial birth-death process (Xt, Yt) which converges towards the distribution of (X, Y). We study the joint distribution of X and Y, and their marginal and conditional distributions. In particular, we introduce a fast and easy simulation procedure for Y conditional on X. This may be used for model checking: given a model for the Papangelou intensity of the original spatial point process, this model is used to generate the complementary process, and the resulting superposition is a Poisson process with intensity function β if and only if the true Papangelou intensity is used. Whether the superposition is actually such a Poisson process can easily be examined using well-known results and fast simulation procedures for Poisson processes. We illustrate this approach to model checking in the case of a Strauss process.
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.
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.
Amorphous silicon p-i-n diodes were illuminated with LED-generated trains of rectangular light pulses under various duty-cycle conditions. Our results indicate that such diodes are able to handle modulation rates in excess of 10MHz over a wide range of operating temperatures. Measurements of the dark I-V characteristics show that the shot-noise in properly designed junctions can be reduced to a level comparable to c-Si photodiodes.
THERMID, made of acetylene-terminated polyimide oligomers, was developed by National Starch & Chemical Co. It is capable of forming thicker deposits than conventional polyimides. It is a candidate for a broad array of electronic and optoelectronic applications, including passivation coating, alpha-particle barrier, interlayer dielectric, encapsulation of discrete devices and IC, optical waveguide, and multilayer dielectric for thin hybrids. The study and evaluation of electrical and optical properties of THERMID polyimide give more support to their application in the semiconductor industry.
Nanocluster memories are promising for future non-volatile memory applications. In this work thin SiO2 films were implanted with Ge+ and Si+ and annealed subsequently. Charge storage effects of the MOS capacitors have been studied through I-V and high frequency C-V measurements. Positive voltage pulses lead to a positive flatband voltage shift of the C-V curve. Detrapping by applying negative voltage pulses leads to a negative shift. The achieved programming window using 6 V / 100 ms pulses for Ge based structures is higher than that for Si (2.0 V vs. 0.2 V). However the retention times for Si based memories are longer. For dedicated process parameters microstructural investigations (RBS, XTEM) of Ge+ implanted SiO2 layers showed two bands of clusters, one near the interface SiO2/Si and one in the center of the SiO2 layer.
Milk contains immunomodulatory compounds that may be important to protect the immature intestine in preterm neonates from harmful inflammatory reactions involved in disorders like necrotising enterocolitis (NEC). We hypothesised that bovine colostrum and milk formulas enriched with sialic acids (SL), gangliosides (Gang) or osteopontin (OPN) would improve gastrointestinal function and NEC resistance in preterm neonates. Forty-seven caesarean-delivered preterm pigs were given total parenteral nutrition for 2 d followed by 1·5 d of enteral feeding. In Expt 1, a control formula was compared with an OPN-enriched formula (n 13), while Expt 2 compared a control formula with bovine colostrum or formulas enriched with Gang or SL (n 4–6). OPN enrichment decreased NEC severity relative to control formula (P < 0·01), without any significant effects on NEC incidence, digestive enzyme activities and hexose absorption. Neither SL- nor Gang-enriched formulas improved NEC resistance or digestive functions, while all the intestinal functional parameters were significantly improved in pigs fed bovine colostrum, relative to formula. The effects in vivo were supported in vitro by bacteria- and dose-dependent modulation by colostrum whey of the cytokine response from bacteria-stimulated murine bone marrow-derived dendritic cells (DC). In conclusion, OPN had only moderate NEC-protective effects, while formulas enriched with Gang or SL were ineffective. The observed modulation of DC cytokine response by bovine colostrum whey in vitro may be due to a synergistic action of various milk bioactives, and it may explain its beneficial effects on NEC development and intestinal function in a piglet model of preterm infants.
Phyto-oestrogens are believed to have a range of beneficial effects on predominant Western diseases. A few studies on phyto-oestrogens in milk exist and show that the composition can be affected by feeding. Therefore, the aim was to study how feeding of lucerne and grass/clover silages (GCSs) affects the concentration of phyto-oestrogens in bovine milk. Sixteen Danish Holstein cows were assigned to a 4 × 4 latin square design with four cows per treatment per period of 3 weeks. The four treatment diets were lucerne silage (LS), 2/3 lucerne silage and 1/3 maize silage (2/3LS), 1/3 lucerne silage and 2/3 maize silage (1/3LS) and GCS. Milk was collected at the end of each period and feed samples on day 6, 13 and 20 in each experimental period. Milk and pooled feed samples were analysed for the concentration of isoflavones, coumestans and lignans. The content of isoflavones was higher and the content of coumestrol lower in the GCS diet than in LS, 2/3LS and 1/3LS diets. For the LS, 2/3LS and 1/3LS diets, the concentration of coumestrol and secoisolariciresinol increased with the proportion of lucerne while the concentration of isoflavones was similar across the diets. The concentrations of the formononetin, daidzein and equol in the milk were significantly higher for the GCS diet than for the LS, 2/3LS and 1/3LS diets. In particular, the concentration of equol was 62–291 times higher for GCS. The concentration of coumestrol was significantly lower for the GCS diet compared to the LS, 2/3LS and 1/3LS diets. No pattern for the concentration of lignans was observed. In conclusion, a high concentration of isoflavones, particularly equol, and a low concentration of coumestrol were measured in the milk from the GCS diet. In contrast, a low concentration of isoflavones and a high concentration of coumestrol were measured in the milk from the LS, 2/3LS and 1/3LS diets. However, the concentration of phyto-oestrogens in bovine milk is low compared to food sources rich in phyto-oestrogens but the high concentration of equol could possibly be of therapeutic importance.