Background
The aim of this study was to investigate the prevalence of epidemiologic and physician‐diagnosed pollen‐induced AR (PiAR) in the grasslands of northern China and to study the impact of the ...intensity and time of pollen exposure on PiAR prevalence.
Methods
A multistage, clustered and proportionately stratified random sampling with a field interviewer‐administered survey study was performed together with skin prick tests (SPT) and measurements of the daily pollen count.
Results
A total of 6043 subjects completed the study, with a proportion of 32.4% epidemiologic AR and 18.5% PiAR. The prevalence was higher in males than females (19.6% vs 17.4%, P = .024), but no difference between the two major residential and ethnic groups (Han and Mongolian) was observed. Subjects from urban areas showed higher prevalence of PiAR than rural areas (23.1% vs 14.0%, P < .001). Most PiAR patients were sensitized to two or more pollens (79.4%) with artemisia, chenopodium, and humulus scandens being the most common pollen types, which were similarly found as the top three sensitizing pollen allergens by SPT. There were significant regional differences in the prevalence of epidemiologic AR (from 18.6% to 52.9%) and PiAR (from 10.5% to 31.4%) among the six areas investigated. PiAR symptoms were positively associated with pollen counts, temperature, and precipitation (P < .05), but negatively with wind speed and pressure P < .05).
Conclusion
Pollen‐induced AR (PiAR) prevalence in the investigated region is extremely high due to high seasonal pollen exposure, which was influenced by local environmental and climate conditions.
Cross-resonance (CR) gates have emerged as a promising scheme for fault-tolerant quantum computation with fixed-frequency qubits. We experimentally implement an entangling CR gate by using a ...microwave-only control in a tunable coupling superconducting circuit, where the tunable coupler provides extra degrees of freedom to verify optimal conditions for constructing a CR gate. By developing a three-qubit Hamiltonian tomography protocol, we systematically investigate the dependency of gate fidelities on spurious qubit interactions and present the first experimental approach to the evaluation of the perturbation impact arising from spectator qubits. Our results reveal that the spectator qubits lead to reductions in CR gate fidelity dependent on Z Z interactions and particular frequency detunings between spectator and gate qubits. The target spectator demonstrates a more serious impact than the control spectator under a standard echo pulse scheme, whereas the degradation of gate fidelity is observed up to 22.5% as both the spectators are present with a modest ZZ coupling to the computational qubits. Our experiments uncover an optimal CR operation regime, and the method we develop here can readily be applied to improving other kinds of two-qubit gates in large-scale quantum circuits.
ABSTRACT A sample of the Large Sky Area Multi-Object Fibre Spectroscopic Telescope spectra of early-type M0-M3 dwarfs is compared with Kepler observations. It is found that M dwarfs with strong ...chromospheric emission in have large flare activity in general. The rotational periods derived from the Kepler measurements have close correlations with the sizes of the flares, the power-law distribution index, and the equivalent widths of the emission. A clear trend exists for higher magnetic activities being detected in faster-rotating M dwarfs (rotation periods < 20 days).
MicroRNAs (miRNAs) are believed to have fundamental roles in tumorigenesis and have great potential for the diagnosis and treatment of cancer. However, the roles of miRNAs in hepatocellular ...carcinogenesis are still not fully elucidated. We investigated the aberrantly expressed miRNAs involved in hepatoma by comparison of miRNA expression profiles in cancerous hepatocytes with normal primary human hepatocytes, and 37 dysregulated miRNAs were screened out by twofold change with a significant difference (P<0.05). Clustering analysis based on 13 miRNAs with changes over 15-folds showed that the miRNA expression patterns between the cancerous and normal hepatocytes were clearly different. Among the 13 miRNAs, we found that miR-375 was significantly downregulated in hepatocellular carcinoma (HCC) tissues and cell lines. Overexpression of miR-375 in liver cancer cells decreased cell proliferation, clonogenicity, migration/invasion and also induced G1 arrest and apoptosis. To unveil the molecular mechanism of miR-375-mediated phenotype in hepatoma cells described above, we examined the putative targets using bioinformatics tools and found that astrocyte elevated gene-1 (AEG-1) was a potential target of miR-375. Then we demonstrated that miR-375 bound directly to the 3'-untranslated region of AEG-1 and inhibited the expression of AEG-1. TaqMan quantitative reverse transcriptase-PCR and western blot analysis showed that miR-375 expression was inversely correlated with AEG-1 expression in HCC tissues. Knockdown of AEG-1 by RNAi in HCC cells, similar to miR-375 overexpression, suppressed tumor properties. Ectopic expression of AEG-1, conversely, could partially reverse the antitumor effects of miR-375. In a mouse model, therapeutic administration of cholesterol-conjugated 2'-O-methyl-modified miR-375 mimics (Chol-miR-375) could significantly suppress the growth of hepatoma xenografts in nude mice. In conclusion, our findings indicate that miR-375 targets AEG-1 in HCC and suppresses liver cancer cell growth in vitro and in vivo, and highlight the therapeutic potential of miR-375 in HCC treatment.
We present an empirical stellar spectra library created using spectra from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) DR5. This library represents a uniform data set ...ranging from 3750 through 8500 K in effective temperature (Teff), from −2.5 through +1.0 dex in metallicity (Fe/H), and from 0 to 5.0 dex in gravity (log g). The spectra in the library have resolutions R ∼ 1800, with well-calibrated fluxes and rest-framed wavelengths. Using a large number of red stars observed by LAMOST, we generated denser K-type templates to fill in data missing from current empirical spectral libraries, particularly the late K type. For K giants, we calibrated the spectroscopic surface gravities against the asteroseismic surface gravities. To verify the reliability of the parameters labeled for this library, we performed an internal cross-validation using a χ2 minimization method to interpolate the parameters of each individual spectrum using the remaining spectra in the library. We obtained precisions of 41 K, 0.11 dex, and 0.05 dex for Teff, log g, and Fe/H, respectively, which means the templates are labeled with correct stellar parameters. Through external comparisons, we confirmed that measurements of the stellar parameters through this library can achieve accuracies of approximately 125 K in Teff, 0.1 dex in Fe/H and 0.20 dex in log g without systematic offset. This empirical library is useful for stellar parameter measurements because it has large parameter coverage and full wavelength coverage from 3800 to 8900 .
Hyperflares of M Dwarfs Chang, H.-Y.; Lin, C.-L.; Ip, W.-H. ...
The Astrophysical journal,
11/2018, Letnik:
867, Številka:
1
Journal Article
Recenzirano
From a study of the light curves of the M dwarfs observed by the Kepler space telescope in its primary mission, a number of flare events with the peak flux increases reaching more than the nominal ...stellar luminosity have been found. One of them, KIC 9201463, produced an extreme flare with the peak flux increase jumping to five times the quiet-time value. In relative terms, this class of hyperflares is much stronger than the superflares of the solar-type stars and could have a very important influence on the atmospheric evolution and the potential development of biospheres of habitable super-Earths orbiting around M dwarf stars. A cross-correlation of the flare activities of some of these M dwarf stars and their H equivalent width (EW) values derived from the LAMOST project indicates that the H EW values can be used to monitor the occurrence of hyperflares as well as the level of flare activity of different classes of M dwarfs with fast to slow rotations, and hence the long-term environmental effects of star-planet interaction of exoplanets.
ABSTRACT We present preliminary results of the quasar survey in the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) first data release (DR1), which includes the pilot survey and ...the first year of the regular survey. There are 3921 quasars reliably identified, among which 1180 are new quasars discovered in the survey. These quasars are at low to median redshifts, with a highest z of 4.83. We compile emission line measurements around the H , Hβ, Mg ii, and C iv regions for the new quasars. The continuum luminosities are inferred from SDSS photometric data with model fitting, as the spectra in DR1 are non-flux-calibrated. We also compile the virial black hole mass estimates, with flags indicating the selection methods, and broad absorption line quasars. The catalog and spectra for these quasars are also available. Of the 3921 quasars, 28% are independently selected with optical-infrared colors, indicating that the method is quite promising for the completeness of the quasar survey. LAMOST DR1 and the ongoing quasar survey will provide valuable data for studies of quasars.
Vertically propagating low‐frequency inertia‐gravity waves (IGWs) are retrieved from meteor radar winds observed at King Sejong Station (KSS: 62.22°S, 58.78°W), Antarctica. IGW horizontal winds ...extracted from temporal band‐pass filtering in regular time‐height bins show the frequent occurrence of IGWs with the downward phase progression and the counterclockwise rotation of their horizontal wind vectors with time (i.e., upward energy propagation) near the mesopause region throughout the whole year of 2014. The vertical wavelengths of the observed IGWs roughly range from 14 km to more than 20 km, which is consistent with previous observational studies on the mesospheric IGWs over Antarctica. Stokes parameters and rotary spectra computed from the hodographs of the IGW horizontal wind components reveal that the intrinsic frequencies of the upward propagating IGWs are |f|−3|f| with seasonal variations of the relative predominance between |f|−2|f| and 2|f|−3|f|, where f is the Coriolis parameter at KSS. The hodograph analysis also indicates that the N‐S propagation is dominant in austral summer, while the NE‐SW propagation is pronounced in austral winter. The propagation direction is discussed in relation to the generation of IGWs due to dynamical imbalances occurring in the tropospheric and stratospheric jet flow systems. Ray tracing results indicate that the N‐S propagation in summer may be due to the jet flow systems roughly north of KSS and the NE‐SW propagation in winter may be either the SW propagation from the jet flow systems northeast of KSS or the NE propagation (around the South Pole) from the south of Australia and Southern Indian and Pacific Oceans.
Key Points
Vertically propagating IGWs are retrieved from meteor radar winds observed at King Sejong Station, Antarctica
Low‐frequency IGWs with intrinsic frequencies of |f|−3|f| occur frequently near the southern mesopause throughout a whole year
Horizontal propagation directions of the low‐frequency IGWs arerelated to the tropospheric and stratospheric jet flow systems
The current therapies to treat hepatitis B virus (HBV) infection are limited. Recently, clustered regularly interspaced short palindromic repeat (CRISPR) systems, originally identified in bacteria ...and archaea, have been found to consist of an RNA-based adaptive immune system that degrades complimentary sequences of invading plasmids and viruses. Here, we studied the effects of the CRISPR/CRISPR-associated Cas9 system that was targeted to the surface antigen (HBsAg)-encoding region of HBV, both in a cell culture system and in vivo. The HBsAg levels in the media of the cells and in the sera of mice were analyzed by a quantitative enzyme-linked immunosorbent assay. The HBV DNA levels were assessed by quantitative PCR and HBsAg expression in mouse livers was assessed by an immunohistochemical assay. The amount of HBsAg secreted in the cell culture and mouse serum was reduced by CRISPR/Cas9 treatment. Immunohistochemistry analyses showed almost no HBsAg-positive cells in the liver tissue of CRISPR/Cas9-S1+X3-treated mice. The CRISPR/Cas9 system efficiently produced mutations in HBV DNA. Thus, CRISPR/Cas9 inhibits HBV replication and expression in vitro and in vivo and may constitute a new therapeutic strategy for HBV infection.
Osteoporosis is a complex multifactorial disease that can lead to an increased risk of fracture. However, selective and effective osteoporosis drugs are still lacking. We showed that Asperosaponin VI ...(AVI) has the implications to be further developed as an alternative supplement for the prevention and treatment of bone loss. AVI has been found to have beneficial effects on metabolic diseases such as bone loss, obesity, and atherosclerosis. Our study was designed to determine the effect and mechanism of action of AVI against bone loss through regulating microbial dysbiosis. A hindlimb unloading mouse model was established to determine the effect of AVI on bone microarchitecture, gut microbiota, and serum metabolites. Eighteen female C57BL/6 J mice were divided into three groups: control, hindlimb unloading with vehicle (HLU), and hindlimb unloading treated with AVI (HLU-AVI, 200 mg/kg/day). AVI was administrated orally for 4 weeks. The results demonstrated that AVI improved the bone microstructure by reversing the decrease in bone volume fraction and trabecular number, and the increase in trabecular separation and structure model index of cancellous bone in hindlimb suspension mice. The results of 16sRNA gene sequencing suggested that the therapeutic effect of AVI on bone loss may be achieved through it regulating the gut microbiota, especially certain specific microorganisms. Combined with the analysis of ELISA, immunohistochemistry, and serum metabolome results, it could be speculated that AVI played an important role in adjusting the balance of bone metabolism by influencing specific flora such as
Clostridium
and its metabolites to regulate the 5-hydroxytryptophan pathway. The study explored the novel mechanism of AVI against osteoporosis, and has implications for the further development of AVI as an alternative supplement for the prevention and treatment of bone loss.
Graphical Abstract
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