A wide variety of industrial applications require materials with high strength and ductility. Unfortunately, the strategies for increasing material strength, such as processing to create line defects ...(dislocations), tend to decrease ductility. We developed a strategy to circumvent this in inexpensive, medium manganese steel. Cold rolling followed by low-temperature tempering developed steel with metastable austenite grains embedded in a highly dislocated martensite matrix. This deformed and partitioned (D and P) process produced dislocation hardening but retained high ductility, both through the glide of intensive mobile dislocations and by allowing us to control martensitic transformation. The D and P strategy should apply to any other alloy with deformation-induced martensitic transformation and provides a pathway for the development of high-strength, high-ductility materials.
Four 2-(styryl)triphenylene derivatives (TSs) were synthesized for deep-blue dopant materials. By using a pyrene-containing compound, DMPPP, as the host, the TS-doped devices exhibited significant ...delayed fluorescence via triplet-triplet annihilation, providing the highest quantum efficiency of 10.2% and a current efficiency of 12.3 cd A(-1).
Experimental evidence indicates that bainitic ferrite formed by transformation at low temperatures (200–350°C) contains quantities of carbon in solid solution far beyond those expected from ...para-equilibrium. A change in the conventional symmetry of the bainitic ferrite lattice from cubic to tetragonal explains the abnormal solid solubility detected. This carbon supersaturation was measured by atom probe tomography, and the tetragonality of the bainitic ferrite, was characterized by means of X-ray diffraction analysis and high resolution transmission electron microscopy.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus with high nucleotide identity to SARS-CoV and to SARS-related coronaviruses that have been detected in horseshoe ...bats, has spread across the world and had a global effect on healthcare systems and economies
. A suitable small animal model is needed to support the development of vaccines and therapies. Here we report the pathogenesis and transmissibility of SARS-CoV-2 in golden (Syrian) hamsters (Mesocricetus auratus). Immunohistochemistry assay demonstrated the presence of viral antigens in nasal mucosa, bronchial epithelial cells and areas of lung consolidation on days 2 and 5 after inoculation with SARS-CoV-2, followed by rapid viral clearance and pneumocyte hyperplasia at 7 days after inoculation. We also found viral antigens in epithelial cells of the duodenum, and detected viral RNA in faeces. Notably, SARS-CoV-2 was transmitted efficiently from inoculated hamsters to naive hamsters by direct contact and via aerosols. Transmission via fomites in soiled cages was not as efficient. Although viral RNA was continuously detected in the nasal washes of inoculated hamsters for 14 days, the communicable period was short and correlated with the detection of infectious virus but not viral RNA. Inoculated and naturally infected hamsters showed apparent weight loss on days 6-7 post-inoculation or post-contact; all hamsters returned to their original weight within 14 days and developed neutralizing antibodies. Our results suggest that features associated with SARS-CoV-2 infection in golden hamsters resemble those found in humans with mild SARS-CoV-2 infections.
STRUCTURAL PARAMETERS OF GALAXIES IN CANDELS van der Wel, A; Bell, E F; Haussler, B ...
The Astrophysical journal. Supplement series,
12/2012, Letnik:
203, Številka:
2
Journal Article
Recenzirano
Odprti dostop
We present global structural parameter measurements of 109,533 unique, H sub(F160W)-selected objects from the CANDELS multi-cycle treasury program. Sersic model fits for these objects are produced ...with GALFIT in all available near-infrared filters (H sub(F160W), J sub(F125W) and, for a subset, Y sub(F105W)). The parameters of the best-fitting Sersic models (total magnitude, half-light radius, Sersic index, axis ratio, and position angle) are made public, along with newly constructed point-spread functions for each field and filter. Random uncertainties in the measured parameters are estimated for each individual object based on a comparison between multiple, independent measurements of the same set of objects. To quantify systematic uncertainties, we create a mosaic with simulated galaxy images with a realistic distribution of input parameters and then process and analyze the mosaic in an identical manner as the real data. We find that accurate and precise measurements-to 10% or better-of all structural parameters can typically be obtained for galaxies with H sub(F160W) < 23, with comparable fidelity for basic size and shape measurements for galaxies to H sub(F160W) ~ 24.5.
Spectroscopic + photometric redshifts, stellar mass estimates, and rest-frame colors from the 3D-HST survey are combined with structural parameter measurements from CANDELS imaging to determine the ...galaxy size-mass distribution over the redshift range 0 < z < 3. Separating early- and late-type galaxies on the basis of star-formation activity, we confirm that early-type galaxies are on average smaller than late-type galaxies at all redshifts, and we find a significantly different rate of average size evolution at fixed galaxy mass, with fast evolution for the early-type population, R sub(eff) is proportional to (1 + z) super(-1.48), and moderate evolution for the late-type population, R sub(eff) is proportional to (1 + z) super(-0.75). The intrinsic scatter is lap0.2 dex for all galaxy types and redshifts. For late-type galaxies, the logarithmic size distribution is not symmetric but is skewed toward small sizes: at all redshifts and masses, a tail of small late-type galaxies exists that overlaps in size with the early-type galaxy population.
Context.
While it is generally assumed that Class II sources evolve largely in isolation from their environment, many still lie close to molecular clouds and may continue to interact with them. This ...may result in late accretion of material onto the disk that can significantly influence disk processes and planet formation.
Aims.
In order to systematically study late infall of gas onto disks, we identify candidate Class II sources in close vicinity to a reflection nebula (RN) that may be undergoing this process.
Methods.
First we targeted Class II sources with known kilo-au scale gas structures – possibly due to late infall of material – and we searched for RNe in their vicinity in optical and near-infrared images. Second, we compiled a catalogue of Class II sources associated with RNe and looked for the large-scale CO structures in archival ALMA data. Using the catalogues of protostars and RNe, we also estimated the probability of Class II sources interacting with surrounding material.
Results.
All of the sources with large-scale gas structures also exhibit some reflection nebulosity in their vicinity. Similarly, at least five Class II objects associated with a prominent RNe, and for which adequate ALMA observations are available, were found to have spirals or stream-like structures which may be due to late infall. We report the first detection of these structures around S CrA.
Conclusions.
Our results suggest that a non-negligible fraction of Class II disks in nearby star-forming regions may be associated with RNe and could therefore be undergoing late accretion of gas. Surveys of RNe and kilo-au scale gas structures around Class II sources will allow us to better understand the frequency and impact of late-infall phenomena.
BACKGROUND:The impact of gut microbiota on the regulation of host physiology has recently garnered considerable attention, particularly in key areas such as the immune system and metabolism. These ...areas are also crucial for the pathophysiology of and repair after myocardial infarction (MI). However, the role of the gut microbiota in the context of MI remains to be fully elucidated.
METHODS:To investigate the effects of gut microbiota on cardiac repair after MI, C57BL/6J mice were treated with antibiotics 7 days before MI to deplete mouse gut microbiota. Flow cytometry was applied to examine the changes in immune cell composition in the heart. 16S rDNA sequencing was conducted as a readout for changes in gut microbial composition. Short-chain fatty acid (SCFA) species altered after antibiotic treatment were identified by high-performance liquid chromatography. Fecal reconstitution, transplantation of monocytes, or dietary SCFA or Lactobacillus probiotic supplementation was conducted to evaluate the cardioprotective effects of microbiota on the mice after MI.
RESULTS:Antibiotic-treated mice displayed drastic, dose-dependent mortality after MI. We observed an association between the gut microbiota depletion and significant reductions in the proportion of myeloid cells and SCFAs, more specifically acetate, butyrate, and propionate. Infiltration of CX3CR1+ monocytes to the peri-infarct zone after MI was also reduced, suggesting impairment of repair after MI. Accordingly, the physiological status and survival of mice were significantly improved after fecal reconstitution, transplantation of monocytes, or dietary SCFA supplementation. MI was associated with a reorganization of the gut microbial community such as a reduction in Lactobacillus. Supplementing antibiotic-treated mice with a Lactobacillus probiotic before MI restored myeloid cell proportions, yielded cardioprotective effects, and shifted the balance of SCFAs toward propionate.
CONCLUSIONS:Gut microbiota–derived SCFAs play an important role in maintaining host immune composition and repair capacity after MI. This suggests that manipulation of these elements may provide opportunities to modulate pathological outcome after MI and indeed human health and disease as a whole.
The responsible behaviour of consumers that purchase green computers is a form of sustainable consumption, as green computers use less energy resulting in less CO2 emissions and the use of fewer ...toxic metals and materials during their production. The research question is how to encourage such behaviour. Although prior research has provided some answers by investigating the antecedents of the behaviour, it has done so through a piecemeal approach from the angles of the theory of planned behaviour (TPB), the value-belief-norm (VBN) theory, and habits. The present research aims to investigate the antecedents of the responsible acquisition of computers behaviour (RACB) among Malaysian consumers by integrating the TPB and the VBN theory with the habits variable. Hypotheses and a research framework were developed based on these theories and a survey questionnaire was used to collect information on the green computer purchase behaviour of computer owners aged 17 and over in Malaysia. A total of 1,000 usable surveys were completed and structural equation modelling was used to analyse the data collected. The findings reveal that the TPB, the VBN theory, and the habits variable can be integrated to explain RACB, which is formed when biospheric values trigger subjective norms that subsequently result in the formation of habits that lead to intentions of acquiring green computers and RACB. The study's findings show that although personal norms do not affect RACB, subjective norms affect ascriptions of responsibility, personal norms, and RACB. The findings provide insights to policymakers, NGOs, manufacturers, and marketers that can assist them in designing strategies for the effective promotion of RACB.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
PDF
