With a suite of multi-modal and multi-scale characterization techniques, the present study unambiguously proves that a substantially-improved combination of ultrahigh strength and good ductility can ...be achieved by tailoring the volume fraction, morphology, and carbon content of the retained austenite (RA) in a transformation-induced-plasticity (TRIP) steel with the nominal chemical composition of 0.19C–0.30Si–1.76Mn–1.52Al (weight percent, wt%). After intercritical annealing and bainitic holding, a combination of ultimate tensile strength (UTS) of 1100MPa and true strain of 50% has been obtained, as a result of the ultrafine RA lamellae, which are alternately arranged in the bainitic ferrite around junction regions of ferrite grains. For reference, specimens with a blocky RA, prepared without the bainitic holding, yield a low ductility (35%) and a low UTS (800MPa). The volume fraction, morphology, and carbon content of RA have been characterized using various techniques, including the magnetic probing, scanning electron microscopy (SEM), electron-backscatter-diffraction (EBSD), and transmission electron microscopy (TEM). Interrupted tensile tests, mapped using EBSD in conjunction with the kernel average misorientation (KAM) analysis, reveal that the lamellar RA is the governing microstructure component responsible for the higher mechanical stability, compared to the blocky one. By coupling these various techniques, we quantitatively demonstrate that in addition to the RA volume fraction, its morphology and carbon content are equally important in optimizing the strength and ductility of TRIP-assisted steels.
The notion of a quasiparticle, such as a phonon, a roton or a magnon, is used in modern condensed matter physics to describe an elementary collective excitation. The intrinsic zero-temperature magnon ...damping in quantum spin systems can be driven by the interaction of the one-magnon states and multi-magnon continuum. However, detailed experimental studies on this quantum many-body effect induced by an applied magnetic field are rare. Here we present a high-resolution neutron scattering study in high fields on an S=1/2 antiferromagnet C
H
N
CuBr
. Compared with the non-interacting linear spin-wave theory, our results demonstrate a variety of phenomena including field-induced renormalization of one-magnon dispersion, spontaneous magnon decay observed via intrinsic linewidth broadening, unusual non-Lorentzian two-peak structure in the excitation spectra and a dramatic shift of spectral weight from one-magnon state to the two-magnon continuum.
Neonatal adiposity is associated with a higher risk of obesity and cardiometabolic risk factors in later life. It is however unknown if central food intake regulating networks in the ventral striatum ...are altered with in-utero abdominal growth, indexed by neonatal adiposity in our current study. We aim to examine the relationship between striatal microstructure and abdominal adipose tissue compartments (AATCs) in Asian neonates from the Growing Up in Singapore Toward healthy Outcomes mother-offspring cohort.
About 109 neonates were included in this study. Magnetic resonance imaging (MRI) was performed for the brain and abdominal regions between 5 to 17 days of life. Diffusion-weighted imaging of the brain was performed for the derivation of caudate and putamen fractional anisotropy (FA). Abdominal imaging was performed to quantify AATCs namely superficial subcutaneous adipose tissue (sSAT), deep subcutaneous adipose tissue (dSAT), and internal adipose tissue (IAT). Absolute and percentage adipose tissue of total abdominal volume (TAV) were calculated.
We showed that AATCs at birth were significantly associated with increased FA in bilateral ventral caudate heads which are part of the ventral striatum (sSAT: β
= 0.56, p < 0.001; β
= 0.65, p < 0.001, dSAT: β
= 0.43, p < 0.001; β
= 0.52, p < 0.001, IAT: β
= 0.30, p = 0.005; β
= 0.32, p = 0.002) in neonates with low birth weights adjusted for gestational age.
Our study provides preliminary evidence of a potential relationship between neonatal adiposity and in-utero programming of the ventral striatum, a brain structure that governs feeding behavior.
This paper presents a novel technique to suppress common-mode electromagnetic interference (EMI) using a digital active EMI filter (DAEF). The DAEF control technique is concurrently implemented with ...a digital controller of a grid-tied photovoltaic microinverter. A brief description of the microinverter architecture and its inverter circuit is illustrated. The inverter stability is investigated using the overall transfer function. Accordingly, the system compensation is designed based on the direct quadrant (DQ) reference frame control technique. Finally, the proposed digital controller is tested on a grid-connected 200-W dc-ac microinverter. The experiment results validate the effectiveness of the proposed technique. Compared with the conventional passive EMI filter, the proposed digital controller can achieve an equivalent or better performance in terms of EMI suppression and maintain stability within the operation bandwidth. Therefore, the embedded DAEF can significantly reduce the size, cost, and space of the overall power inverter printed circuit board without the need of a conventional passive EMI filter.
Bronchial biopsy specimens from chronic obstructive pulmonary disease (COPD) patients demonstrate increased numbers of CD8+ T-lymphocytes, macrophages and, in some studies, neutrophils and ...eosinophils. Smoking cessation affects the rate of forced expiratory volume in one second (FEV(1)) decline in COPD, but the effect on inflammation is uncertain. Bronchial biopsy inflammatory cell counts were compared in current and ex-smokers with COPD. A pooled analysis of subepithelial inflammatory cell count data from three bronchial biopsy studies that included COPD patients who were either current or ex-smokers was performed. Cell count data from 101 subjects, 65 current smokers and 36 ex-smokers, were analysed for the following cell types: CD4+ and CD8+ T-lymphocytes, CD68+ (monocytes/macrophages), neutrophil elastase+ (neutrophils), EG2+ (eosinophils), mast cell tryptase+ and cells mRNA-positive for tumour necrosis factor-alpha. Current smokers and ex-smokers were similar in terms of lung function, as measured by FEV(1) (% predicted), forced vital capacity (FVC) and FEV(1)/FVC. The results demonstrate that there were no significant differences between smokers and ex-smokers in the numbers of any of the inflammatory cell types or markers analysed. It is concluded that, in established chronic obstructive pulmonary disease, the bronchial mucosal inflammatory cell infiltrate is similar in ex-smokers and those that continue to smoke.
ABSTRACT
We present timing solutions and analyses of 11 pulsars discovered by the Five-hundred-meter Aperture Spherical radio Telescope (FAST). These pulsars were discovered using an ultrawide ...bandwidth receiver in drift-scan observations made during the commissioning phase of FAST, and were then confirmed and timed using the 64-m Parkes Radio Telescope. Each pulsar has been observed over a span of at least one year. Highlighted discoveries include PSR J0344−0901, which displays mode-changing behaviour and may belong to the class of so-called swooshing pulsars (alongside PSRs B0919+06 and B1859+07); PSR J0803−0942, whose emission is almost completely linearly polarized; and PSRs J1900−0134 and J1945+1211, whose well-defined polarization angle curves place stringent constraints on their emission geometry. We further discuss the detectability of these pulsars by earlier surveys, and highlight lessons learned from our work in carrying out confirmation and monitoring observations of pulsars discovered by a highly sensitive telescope, many of which may be applicable to next-generation pulsar surveys. This paper marks one of the first major releases of FAST-discovered pulsars, and paves the way for future discoveries anticipated from the Commensal Radio Astronomy FAST Survey.
The South China Sea is the largest marginal basin of SE Asia, yet its mechanism of formation is still debated. A 1000-km long wide-angle refraction seismic profile was recently acquired along the ...conjugate margins of the SW sub-basin of the South China Sea, over the longest extended continental crust. A joint reflection and refraction seismic travel time inversion is performed to derive a 2-D velocity model of the crustal structure and upper mantle. Based on this new tomographic model, northern and southern margins are genetically linked since they share common structural characteristics. Most of the continental crust deforms in a brittle manner. Two scales of deformation are imaged and correlate well with seismic reflection observations. Small-scale normal faults (grabens, horsts and rotated faults blocks) are often associated with a tilt of the velocity isocontours affecting the upper crust. The mid-crust shows high lateral velocity variation defining low velocity bodies bounded by large-scale normal faults recognized in seismic reflection profiles. Major sedimentary basins are located above low velocity bodies interpreted as hanging-wall blocks. Along the northern margin, spacing between these velocity bodies decreases from 90 to 45 km as the total crust thins toward the Continent–Ocean Transition. The Continent–Ocean Transitions are narrow and slightly asymmetric – 60 km on the northern side and no more than 30 km on the southern side – indicating little space for significant hyper-stretched crust. Although we have no direct indication for mantle exhumation, shallow high velocities are observed at the Continent–Ocean Transition. The Moho interface remains rather flat over the extended domain, and remains undisturbed by the large-scale normal faults. The main décollement is thus within the ductile lower crust.
•Wide-angle refraction seismic images the conjugate margins of the South China Sea.•Moho interface remains rather smooth over the extended domain.•Crust at mid-depth (10 km bsf) shows fault-related lateral velocity variations.•Large-scale normal faults root in the lower ductile crust.•The crust is partly composed of inherited granitic plutons of Yanshanian origin.
Aspergillus fumigatus
is one of the most prominent opportunistic fungal pathogens in immunocompromised hosts. Early recognition of this infection along with prompt antifungal therapy may increase the ...survival rate. We expressed two potential bio-markers of
A. fumigatus
infection—galactomannoprotein Afmp1p and Afmp4p in
Pichia pastoris
. We generated 33 monoclonal antibodies (MAbs), 20 against recombinant Afmp1p (rAfmp1p) and the other 13 against recombinant Afmp4p (rAfmp4p). Subsequently, we developed two antigen-capture enzyme-linked immunosorbent assays (ELISAs) which employed MAbs as both the capture and the detection antibodies for rAfmp1p and rAfmp4p. The two antigen-capture ELISAs specifically detected Afmp1p/Afmp4p in cultures of
A. fumigatus
and had no cross-reaction with other tested pathogenic fungi, including
Penicillium marneffei
and other pathogenic
Aspergillus
species. The Afmp1p-captured ELISA would be positive even when the culture supernatant of
A. fumigatus
had been diluted to 128-fold of its original concentration. The two antigen ELISAs could capture circulating or excreted antigens during the acute phase of invasive aspergillosis (IA) in the animal model, and had no cross-reactivity to other
Aspergillus
-challenged animal models. We developed two antigen-capture ELISAs for the laboratory diagnosis of
A. fumigatus
infection. These two antigen-capture ELISAs may be useful in the clinical diagnosis of aspergillosis.
Background
Left lateral sectionectomy (LLS) is one of the most commonly performed minimally invasive liver resections. While laparoscopic (L)-LLS is a well-established technique, over traditional ...open resection, it remains controversial if robotic (R)-LLS provides any advantages of L-LLS.
Methods
A post hoc analysis of 997 patients from 21 international centres undergoing L-LLS or R-LLS from 2006 to 2020 was conducted. A total of 886 cases (214 R-LLS, 672 L-LLS) met study criteria. 1:1 and 1:2 propensity score matched (PSM) comparison was performed between R-LLS & L-LLS. Further subset analysis by Iwate difficulty was also performed. Outcomes measured include operating time, blood loss, open conversion, readmission rates, morbidity and mortality.
Results
Comparison between R-LLS and L-LLS after PSM 1:2 demonstrated statistically significantly lower open conversion rate in R-LLS than L-LLS (0.6% versus 5%,
p
= 0.009) and median blood loss was also statistically significantly lower in R-LLS at 50 (80) versus 100 (170) in L-LLS (
p
= 0.011) after PSM 1:1 although there was no difference in the blood transfusion rate. Pringle manoeuvre was also found to be used more frequently in R-LLS, with 53(24.8%) cases versus to 84(12.5%) L-LLS cases (
p
< 0.001). There was no significant difference in the other key perioperative outcomes such as operating time, length of stay, postoperative morbidity, major morbidity and 90-day mortality between both groups.
Conclusion
R-LLS was associated with similar key perioperative outcomes compared to L-LLS. It was also associated with significantly lower blood loss and open conversion rates compared to L-LLS.
•Hypoxia altered the biofilm bacterial community composition.•Biofilms treated with hypoxia resulted in different benthic communities.•The hypoxic treatment was dominated by Hydroides sp.•The ...normoxic treatment was dominated by Folliculina sp.
Biofilms on submerged surfaces are important in determining larval settlement of most marine benthic invertebrates. We investigated if exposure of biofilms to hypoxia would alter the larval settlement pattern and result in a shift in benthic invertebrate community structure in the field. Biofilms were first exposed to hypoxia or normoxia in laboratory microcosms for 7days, and then deployed in the field for another 7days to allow for larval settlement and recruitment to occur. Using terminal-restriction fragment length polymorphism of the 16S rRNA gene, this study showed that hypoxia altered the biofilm bacterial community composition, and the difference between the hypoxic and normoxic treatments increased with the time of exposure period. This study also demonstrated significantly different benthic invertebrate community structures as a result of biofilm exposure to hypoxia and that the hypoxic and normoxic treatments were dominated by Hydroides sp. and Folliculina sp., respectively.
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