185 research outputs found
Directional ordering of fluctuations in a two-dimensional compass model
A classical realization of directional coupling in two dimension of the effective orbital-orbital interaction in the Mott insulating phase of the transition metal oxides (TMO) was presented. The model exhibited partial orbital ordering in the form of directional ordering of fluctuation at low temperatures stabilized by an entropy gap. The directional ordering was necessarily accompanied by a lattice distortion and the bond length in horizontal and vertical directions became unequal when the couplings of the orbital isosopin to lattice modes were included. Analysis shows that the compass model has a low temperature phase which exhibited long-ranged correlations in the directions of fluctuations in both isospin and lattice spaces.published_or_final_versio
Degradation of Cry1Ab protein from genetically modified maize (MON810) in relation to total dietary feed proteins in dairy cow digestion
To investigate the relative degradation and fragmentation pattern of the recombinant Cry1Ab protein from genetically modified (GM) maize MON810 throughout the gastrointestinal tract (GIT) of dairy cows, a 25Â months GM maize feeding study was conducted on 36 lactating Bavarian Fleckvieh cows allocated into two groups (18 cows per group) fed diets containing either GM maize MON810 or nearly isogenic non-GM maize as the respective diet components. All cows were fed a partial total mixed ration (pTMR). During the feeding trial, 8 feed (4 transgenic (T) and 4 non-transgenic (NT) pTMR) and 42 feces (26 T and 18 NT) samples from the subset of cows fed T and NT diets, and at the end of the feeding trial, digesta contents of rumen, abomasum, small intestine, large intestine and cecum were collected after the slaughter of six cows of each feeding group. Samples were analyzed for Cry1Ab protein and total protein using Cry1Ab specific ELISA and bicinchoninic acid assay, respectively. Immunoblot analyses were performed to evaluate the integrity of Cry1Ab protein in feed, digesta and feces samples. A decrease to 44% in Cry1Ab protein concentration from T pTMR to the voided feces (9.40 versus 4.18Â ÎŒg/g of total proteins) was recorded. Concentrations of Cry1Ab protein in GIT digesta of cows fed T diets varied between the lowest 0.38Â ÎŒg/g of total proteins in abomasum to the highest 3.84Â ÎŒg/g of total proteins in rumen. Immunoblot analysis revealed the extensive degradation of recombinant Cry1Ab protein into a smaller fragment of around 34Â kDa in GIT. The results of the present study indicate that the recombinant Cry1Ab protein from MON810 is increasingly degraded into a small fragment during dairy cow digestion
Internet-of-Things-Enabled Smart Bed Rail for Application in Hospital Beds
This article presents an atypical offline based LoRaWAN application for use in hospital settings, where the ability to maintain network connectivity during internet connection disruption is paramount. A prototype bed rail is demonstrated, providing advanced functionality compared to traditional bed rails. The manufactured prototype provides data to a nurses station reliably and operates under battery backup. The power consumption of the system under different transmission intervals was tested, allowing appropriate battery sizing for different applications to be specified accurately. It is expected that a single LoRaWAN gateway will be able to cover bed rails across an entire modern hospital, allowing minimal infrastructure cost to implement the device or application in a rapidly deployed field hospital.</jats:p
Onset of occupational hand eczema among healthcare workers during the SARSâCoVâ2 pandemic: Comparing a single surgical site with a COVIDâ19 intensive care unit
Background
As a result of the COVIDâ19 outbreak, hygiene regulations have been revised and hand sanitation has been intensified.
Objective
To investigate the onset of hand eczema during the COVIDâ19 pandemic in healthcare workers (HCWs) directly involved in intensive care of COVIDâ19 patients and HCWs without direct contact with COVIDâ19 patients. Hereby, we aim at increasing awareness about occupational hand eczema and preventive measures that can be adopted.
Method
A survey was distributed amongst 114 HCWs at a single surgical centre and at a COVIDâ19 intensive care unit of the university hospital Ludwig Maximilian University Munich, Germany. Participants were questioned about the daily frequency of hand hygiene prior to and during the pandemic. Participants selfâreported the onset of hand eczema and associated symptoms.
Results
Our study revealed a significant increase in hand washing, disinfection, and use of hand cream across all participants (Pâvalue <.001), regardless of having direct contact with COVIDâ19 patients. A high prevalence of symptoms associated with acute hand dermatitis of 90.4% was found across all HCWs, whereas hand eczema itself was underreported (14.9%).
Conclusion
The increase in hand sanitation during the COVIDâ19 pandemic impairs the skin of the hands across all HCWs, independent of direct intensive care of affected patients
Trans-Atlantic exchanges have shaped the population structure of the Lyme disease agent Borrelia burgdorferi sensu stricto
The origin and population structure of Borrelia burgdorferi sensu stricto (s.s.), the agent of Lyme disease, remain obscure. This tick-transmitted bacterial species occurs in both North America and Europe. We sequenced 17 European isolates (representing the most frequently found sequence types in Europe) and compared these with 17 North American strains. We show that trans-Atlantic exchanges have occurred in the evolutionary history of this species and that a European origin of B. burgdorferi s. s. is marginally more likely than a USA origin. The data further suggest that some European human patients may have acquired their infection in North America. We found three distinct genetically differentiated groups: i) the outgroup species Borrelia bissettii, ii) two divergent strains from Europe, and iii) a group composed of strains from both the USA and Europe. Phylogenetic analysis indicated that different genotypes were likely to have been introduced several times into the same area. Our results demonstrate that irrespective of whether B. burgdorferi s. s. originated in Europe or the USA, later trans-Atlantic exchange(s) have occurred and have shaped the population structure of this genospecies. This study clearly shows the utility of next generation sequencing to obtain a better understanding of the phylogeography of this bacterial species
The origin of mid-infrared emission in massive young stellar objects: multi-baseline VLTI observations of W33A
The circumstellar structure on 100 AU scales of the massive young stellar
object W33A is probed using the VLTI and the MIDI instrument. N-band
visibilities on 4 baselines are presented which are inconsistent with a
spherically symmetric geometry. The visibility spectra and SED are
simultaneously compared to 2D axi-symmetric dust radiative transfer models with
a geometry including a rotationally flattened envelope and outflow cavities. We
assume an O7.5 ZAMS star as the central source, consistent with the observed
bolometric luminosity. The observations are also compared to models with and
without (dusty and gaseous) accretion disks. A satisfactory model is
constructed which reproduces the visibility spectra for each (u,v) point. It
fits the silicate absorption, the mid-IR slope, the far-infrared peak, and the
(sub)mm of the SED. It produces a 350 micron morphology consistent with
observations. The 10 micron emission on 100 AU scales is dominated by the
irradiated walls of the cavity sculpted by the outflow. The visibilities rule
out the presence of dust disks with total (gas and dust) masses more than 0.01
Msun. However, optically thick accretion disks, interior to the dust
sublimation radius, are allowed to accrete at rates equalling the envelope's
mass infall rate (up to 10^(-3) Msun/yr) without substantially affecting the
visibilities due to the extinction by the extremely massive envelope of W33A.Comment: Accepted for publication in A&
Probing the envelopes of massive young stellar objects with diffraction limited mid-infrared imaging
Massive stars form whilst they are still embedded in dense envelopes. As a
result, the roles of rotation, mass loss and accretion in massive star
formation are not well understood. This study evaluates the source of the
Q-band, lambda=19.5 microns, emission of massive young stellar objects (MYSOs).
This allows us to determine the relative importance of rotation and outflow
activity in shaping the circumstellar environments of MYSOs on 1000 AU scales.
We obtained diffraction limited mid-infrared images of a sample of 20 MYSOs
using the VLT/VISIR and Subaru/COMICS instruments. For these 8 m class
telescopes and the sample selected, the diffraction limit, ~0.6", corresponds
to approximately 1000 AU. We compare the images and the spectral energy
distributions (SEDs) observed to a 2D, axis-symmetric dust radiative transfer
model that reproduces VLTI/MIDI observations of the MYSO W33A. We vary the
inclination, mass infall rate, and outflow opening angle to simultaneously
recreate the behaviour of the sample of MYSOs in the spatial and spectral
domains. The mid-IR emission of 70 percent of the MYSOs is spatially resolved.
In the majority of cases, the spatial extent of their emission and their SEDs
can be reproduced by the W33A model featuring an in-falling, rotating dusty
envelope with outflow cavities. There is independent evidence that most of the
sources which are not fit by the model are associated with ultracompact HII
regions and are thus more evolved. We find that, in general, the diverse 20
micron morphology of MYSOs can be attributed to warm dust in the walls of
outflow cavities seen at different inclinations. This implies that the warm
dust in the outflow cavity walls dominates the Q-band emission of MYSOs. In
turn, this emphasises that outflows are an ubiquitous feature of massive star
formation.Comment: Accepted for publication in A&A. The images in this version have been
compressed. A high resolution version is available on reques
Providing a âchallenge functionâ:Government social researchers in the UKâs Department of Energy and Climate Change (2010â2015)
Resolved 24.5 micron emission from massive young stellar objects
Massive young stellar objects (MYSO) are surrounded by massive dusty
envelopes. Our aim is to establish their density structure on scales of ~1000
AU, i.e. a factor 10 increase in angular resolution compared to similar studies
performed in the (sub)mm. We have obtained diffraction-limited (0.6") 24.5
micron images of 14 well-known massive star formation regions with
Subaru/COMICS. The images reveal the presence of discrete MYSO sources which
are resolved on arcsecond scales. For many sources, radiative transfer models
are capable of satisfactorily reproducing the observations. They are described
by density powerlaw distributions (n(r) ~ r^(-p)) with p = 1.0 +/-0.25. Such
distributions are shallower than those found on larger scales probed with
single-dish (sub)mm studies. Other sources have density laws that are
shallower/steeper than p = 1.0 and there is evidence that these MYSOs are
viewed near edge-on or near face-on, respectively. The images also reveal a
diffuse component tracing somewhat larger scale structures, particularly
visible in the regions S140, AFGL 2136, IRAS 20126+4104, Mon R2, and Cep A. We
thus find a flattening of the MYSO envelope density law going from ~10 000 AU
down to scales of ~1000 AU. We propose that this may be evidence of rotational
support of the envelope (abridged).Comment: 21 pages, accepted for A&
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