This study examines the influence of radiative heating on the prediction of tropical cyclone (TC) intensification in the Hurricane Weather Research and Forecasting (HWRF) model. Previous idealized ...modeling and observational studies demonstrated that radiative heating can substantially modulate the evolution of TC intensity. However, the relevance of this process under realistic conditions remains unclear. Here, we use observed longwave radiative heating to explore the performance of TC forecasts in HWRF simulations. The performance of TC intensity forecasts is then investigated in the context of radiative heating forecasts. In observations and HWRF forecasts, high clouds near the TC center increase the convergence of radiative fluxes. A sharp spatial gradient (≥60 W/m2) in the flux convergence from the TC center outward toward the environment is associated with subsequent TC intensification. More accurate simulation of the spatial structure of longwave radiative heating is associated with more accurate TC intensity forecasts.
Plain Language Summary
Satellite measurements observed larger radiation heating near the center of intensifying tropical cyclones. Previous idealized modeling studies suggest that this heating facilitates tropical cyclone development. In this study, we investigate how radiative heating affects the ability of a tropical cyclone forecast model to predict tropical cyclone intensification. Our results demonstrate that the model forecasts of intensity improve when the model better reproduces the observed spatial structure of radiative heating associated with the tropical cyclone.
Key Points
Tropical cyclones that intensify tend to have greater longwave convergence within the atmospheric column prior to intensification
An operational forecast model can capture the signal of TC intensification in longwave radiation
The ability to simulate radiation in the forecast model can influence its prediction skills of tropical cyclone intensification
Spitzer data at 24, 70, and 160 {mu}m and ground-based H{alpha} images are analyzed for a sample of 189 nearby star-forming and starburst galaxies to investigate whether reliable star formation rate ...(SFR) indicators can be defined using the monochromatic infrared dust emission centered at 70 and 160 {mu}m. We compare recently published recipes for SFR measures using combinations of the 24 {mu}m and observed H{alpha} luminosities with those using 24 {mu}m luminosity alone. From these comparisons, we derive a reference SFR indicator for use in our analysis. Linear correlations between SFR and the 70 {mu}m and 160 {mu}m luminosity are found for L(70) {approx_gt} 1.4 x 10{sup 42} erg s{sup -1} and L(160) {approx_gt} 2 x 10{sup 42} erg s{sup -1}, corresponding to SFR {approx_gt} 0.1-0.3 M{sub sun} yr{sup -1}, and calibrations of SFRs based on L(70) and L(160) are proposed. Below those two luminosity limits, the relation between SFR and 70 {mu}m (160 {mu}m) luminosity is nonlinear and SFR calibrations become problematic. A more important limitation is the dispersion of the data around the mean trend, which increases for increasing wavelength. The scatter of the 70 {mu}m (160 {mu}m) data around the mean is about 25% (factor {approx}2) larger than the scatter of the 24 {mu}m data. We interpret this increasing dispersion as an effect of the increasing contribution to the infrared emission of dust heated by stellar populations not associated with the current star formation. Thus, the 70 (160) {mu}m luminosity can be reliably used to trace SFRs in large galaxy samples, but will be of limited utility for individual objects, with the exception of infrared-dominated galaxies. The nonlinear relation between SFR and the 70 and 160 {mu}m emission at faint galaxy luminosities suggests a variety of mechanisms affecting the infrared emission for decreasing luminosity, such as increasing transparency of the interstellar medium, decreasing effective dust temperature, and decreasing filling factor of star-forming regions across the galaxy. In all cases, the calibrations hold for galaxies with oxygen abundance higher than roughly 12 +log(O/H) {approx} 8.1. At lower metallicity, the infrared luminosity no longer reliably traces the SFR because galaxies are less dusty and more transparent.
Abstract
The stoichiometric photocatalytic reaction of CO
2
with H
2
O is one of the great challenges in photocatalysis. Here, we construct a Cu
2
O-Pt/SiC/IrO
x
composite by a controlled ...photodeposition and then an artificial photosynthetic system with Nafion membrane as diaphragm separating reduction and oxidation half-reactions. The artificial system exhibits excellent photocatalytic performance for CO
2
reduction to HCOOH and H
2
O oxidation to O
2
under visible light irradiation. The yields of HCOOH and O
2
meet almost stoichiometric ratio and are as high as 896.7 and 440.7 μmol g
−1
h
−1
, respectively. The high efficiencies of CO
2
reduction and H
2
O oxidation in the artificial system are attributed to both the direct Z-scheme electronic structure of Cu
2
O-Pt/SiC/IrO
x
and the indirect Z-scheme spatially separated reduction and oxidation units, which greatly prolong lifetime of photogenerated electrons and holes and prevent the backward reaction of products. This work provides an effective and feasible strategy to increase the efficiency of artificial photosynthesis.
Summary
Background
Proton pump inhibitor (PPI) use has been reported to be associated with liver damage and might possibly be carcinogenic.
Aims
We examined whether long‐term PPI use increases the ...risk of hepatocellular carcinoma (HCC) in patients without viral hepatitis B or C.
Methods
We conducted a nested case‐control study in a cohort of patients without viral hepatitis in Taiwan from 2000 to 2013. In total, 29 473 HCC cases and 294 508 matched controls were included. Moreover, we identified prescriptions for PPI and durations between the PPI index date and cancer diagnosis date (or the corresponding date in controls).
Results
The adjusted odds ratio (AOR) for HCC associated with PPI use was 2.86 (95% confidence interval CI, 2.69‐3.04). Considering the use of PPIs determined according to cumulative defined daily dose (cDDD) subgroups, a dose‐response effect was observed in patients exposed to 29‐180, 181‐240, 241‐300, and 300+ cDDDs of PPIs. The AORs were 2.74 (95% CI, 2.57‐2.93), 2.98 (95% CI, 2.50‐3.56), 3.23 (95% CI, 2.59‐4.02), and 3.43 (95% CI, 2.94‐4.00) in the 29‐180, 181‐240, 241‐300, and 300+ cDDD groups, respectively, compared with the 0‐28 cDDD group. A sensitivity analysis revealed a consistent association between PPI use and the risk of HCC in subpopulations stratified by risk factors associated with HCC.
Conclusions
This observational study demonstrated that PPIs might increase the risk of HCC.
Linked ContentThis article is linked to Mikocka‐Walus and Knowles, and Stapersma et al papers. To view these articles visit https://doi.org/10.1111/apt.14905 and https://doi.org/10.1111/apt.14935.
Aims
Relatively, few anti‐biofilm polysaccharides against Pseudomonas aeruginosa were done to investigate the underlying molecular mechanism. Exopolysaccharide EPS273 can clearly reduce biofilm ...formation and infection of P. aeruginosa. This study aims to investigate its anti‐biofilm and anti‐infection mechanism on transcriptional level.
Methods and Results
Herein, we used an RNA‐Seq transcriptomic approach to investigate the underlying anti‐biofilm and anti‐infection mechanism of EPS273. The expression levels of a large number of genes were changed after P. aeruginosa PAO1 was treated with EPS273. Especially, the genes related to biofilm formation, such as gene involved in production of extracellular matrix and virulence factor, genes involved in flagella and cell motility and genes involved in iron acquisition. Notably, the expression levels of genes involved in regulatory and signal transduction were markedly downregulated, such as two‐component system PhoP‐PhoQ and quorum sensing (QS) system LasI/LasR and RhlI/RhlR. Furthermore, when genes phoP and phoQ were disrupted, respectively, the reduction of biofilm formation and cell motility in mutant △phoP or △phoQ was also detected.
Conclusion
EPS273 may exert its anti‐biofilm and anti‐infection function by downregulating gene expression of two‐component system PhoP‐PhoQ and QS systems LasI/LasR and RhlI/RhlR of P. aeruginosa, which further regulated expression of genes involved in biofilm formation.
Significance and Impact of the Study
Our data will expand understanding of anti‐biofilm mechanisms of polysaccharides on transcriptomic level.
Combining the Mars Atmosphere and Volatile Evolution measurements of neutral atmospheric density, solar EUV/X-ray flux, and differential photoelectron intensity made during 240 nominal orbits, we ...calculate the ionization efficiency, defined as the ratio of the secondary (photoelectron impact) ionization rate to the primary (photon impact) ionization rate, in the dayside Martian upper atmosphere under a range of solar illumination conditions. Both the CO2 and O ionization efficiencies tend to be constant from 160 km up to 250 km, with respective median values of 0.19 0.03 and 0.27 0.04. These values are useful for fast calculation of the ionization rate in the dayside Martian upper atmosphere, without the need to construct photoelectron transport models. No substantial diurnal and solar cycle variations can be identified, except for a marginal trend of reduced ionization efficiency approaching the terminator. These observations are favorably interpreted by a simple scenario with ionization efficiencies, as a first approximation, determined by a comparison between relevant cross sections. Our analysis further reveals a connection between regions with strong crustal magnetic fields and regions with high ionization efficiencies, which are likely indicative of more efficient vertical transport of photoelectrons near magnetic anomalies.
A marigold-like SiC@MoS2 nanoflower with a unique Z-scheme structure efficiently achieves the overall conversion of gas phase CO2 with H2O (CO2 (g) + 2H2O (g) = CH4 + 2O2) without any sacrificial ...reagents under visible light (λ ≥ 420 nm) irradiation. The CH4 and O2 evolution are 323 and 621 μL·g–1·h–1, and stable throughout 5 cycle reactions of total 40 h. This work demonstrates a breakthrough in artificial photosynthesis with the Z-scheme 1D heterojunction constructed by combining 2D semiconductor and 3D semiconductor based on the transfer balance of photogenerated electron and hole.
Abstract We present a new three-dimensional (3D) magnetohydrodynamic (MHD) model and a new 3D energetic particle transport (EPT) model. The 3D MHD model numerically solves the ideal MHD equations ...using the relaxing total variation diminishing scheme. In the 3D MHD simulations, we use simple boundary conditions with a high-speed flow, and we can clearly identify a corotating interaction region (CIR) with the characteristics of forward shock and reverse shock. The 3D EPT model solves the Fokker–Planck transport equation for the solar energetic particles (SEPs) using backward stochastic processes, with the magnetic field and solar wind velocity field from MHD results. For comparison, the 3D EPT model results with Parker fields are also obtained. We investigate the transport of SEPs with particle sources and observers in different positions in MHD fields with a CIR, and we compare the results with those in the Parker fields. Our simulation results show that the compression region with local enhancement of the magnetic field, i.e., CIR, can act as a barrier to scatter energetic particles back, and particles can struggle to diffuse through the strong magnetic field regions. Usually, a normal anisotropy profile is commonly present in SEP simulation results with Parker fields, and it is also typically present in that with MHD fields. However, because of the compression region of the magnetic field, energetic particles may exhibit anomalous anisotropy. This result may be used to replicate the spacecraft observation phenomena of the anomalous anisotropy.
Summary
Effective laboratory markers for the estimation of disease severity and predicting the clinical progression of coronavirus disease‐2019 (COVID‐19) is urgently needed. Laboratory tests, ...including blood routine, cytokine profiles and infection markers, were collected from 389 confirmed COVID‐19 patients. The included patients were classified into mild (n = 168), severe (n = 169) and critical groups (n = 52). The leukocytes, neutrophils, infection biomarkers such as C‐reactive protein (CRP), procalcitonin (PCT) and ferritin and the concentrations of cytokines interleukin (IL)‐2R, IL‐6, IL‐8, IL‐10 and tumor necrosis factor (TNF)‐α were significantly increased, while lymphocytes were significantly decreased with increased severity of illness. The amount of IL‐2R was positively correlated with the other cytokines and negatively correlated with lymphocyte number. The ratio of IL‐2R to lymphocytes was found to be remarkably increased in severe and critical patients. IL‐2R/lymphocytes were superior compared with other markers for the identification of COVID‐19 with critical illness, not only from mild but also from severe illness. Moreover, the cytokine profiles and IL‐2R/lymphocytes were significantly decreased in recovered patients, but further increased in disease‐deteriorated patients, which might be correlated with the outcome of COVID‐19. Lymphopenia and increased levels of cytokines were closely associated with disease severity. The IL‐2R/lymphocyte was a prominent biomarker for early identification of severe COVID‐19 and predicting the clinical progression of the disease.
IL‐2R/lymphocyte was a superior marker for the identification of severe COVID‐19 patients.
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