The ability of the ivy sign on contrast-enhanced T1-weighted MR imaging (CEMR) to reflect cerebral perfusion and postoperative revascularization in Moyamoya disease remains largely unknown. We aimed ...to compare the capabilities of CEMR and FLAIR.
CEMR, FLAIR, arterial spin-labeling, and DSA were performed in 44 patients with Moyamoya disease. The ivy sign was scored separately on CEMR and FLAIR using the Alberta Stroke Program Early CT Score. The status of leptomeningeal collaterals was scored on DSA. The postoperative Matsushima grade was evaluated at least 3 months after surgical revascularization.
Scoring of the ivy sign on CEMR showed excellent interrater reliability, and FLAIR vascular hyperintensity showed moderate interrater reliability. Correlation analyses revealed that DSA scores were more consistent with the CEMR-based ivy sign score (
=
0.25,
= .03) than with FLAIR vascular hyperintensity (
= 0.05,
= .65). The CEMR-based ivy sign score was significantly correlated with CBF in late-Suzuki stage Moyamoya disease (
= -2.64,
= .02). The CEMR-based ivy sign score at baseline was significantly correlated with the postoperative Matsushima grade (
=
0.48,
= .03).
In this study, CEMR outperformed FLAIR in capturing the ivy sign in Moyamoya disease. In addition, the CEMR-based ivy sign score provided adequate information on hemodynamic status and postoperative neovascularization. The current study suggested that CEMR could be considered as an alternative to FLAIR in future studies investigating leptomeningeal collaterals in Moyamoya disease.
We report a systematic study on the crystal growth of the rare-earth titanates R2Ti2O7 (R=Gd, Tb, Dy, Ho, Y, Er, Yb and Lu) and Y-doped Tb2−xYxTi2O7 (x=0.2 and 1) using an optical floating-zone ...method. High-quality single crystals were successfully obtained and the growth conditions were carefully optimized. The oxygen pressure was found to be the most important parameter and the appropriate ones are 0.1–0.4MPa, depending on the radius of rare-earth ions. The growth rate is another parameter and was found to be 2.5–4mm/h for different rare-earth ions. X-ray diffraction data demonstrated the good crystallinity of these crystals. The basic physical properties of these crystals were characterized by the magnetic susceptibility and specific heat measurements.
•R2Ti2O7 single crystals are grown by using floating-zone method.•The growth conditions are optimized.•Structural and physical properties are characterized.
A climate model, coupled to a sophisticated land surface scheme, is used to explore the impact of land use induced land cover change (LULCC) on climate extremes indices recommended by the Expert Team ...on Climate Change Detection and Indices (ETCCDI). The impact from LULCC is contrasted with the impact of doubling atmospheric carbon dioxide (CO2). Many of the extremes indices related to temperature are affected by LULCC and the resulting changes are locally and field significant. Some indices are systematically affected by LULCC in the same direction as increasing CO2 while for others LULCC opposes the impact of increasing CO2. We suggest that assumptions that anthropogenically induced changes in temperature extremes can be approximated just by increasing greenhouse gases are flawed, as LULCC may regionally mask or amplify the impact of increasing CO2 on climate extremes. In some regions, the scale of the LULCC forcing is of a magnitude similar to the impact of CO2 alone. We conclude that our results complicate detection and attribution studies, but also offer a way forward to a clearer and an even more robust attribution of the impact of increasing CO2 at regional scales.
Key Points
Temperature extremes indices are affected by LULCC
LULCC may locally mask or amplify impact of increasing CO2 on extreme indices
Results offer way towards clearer, more robust attribution of CO2 impact
Neovascularization has a critical role in the growth and metastatic spread of tumors, and involves recruitment of circulating endothelial progenitor cells (EPCs) from bone marrow. In this study, we ...examined whether EPCs could promote tumor angiogenesis, and found that the tumor growth was enhanced by the administration of EPCs. To test the hypothesis that genetically modified bone marrow-derived EPCs can be effective carriers of therapeutic agents to tumor sites, we conducted human interferon-beta (HuIFN-β) gene transfection of EPCs with a virus vector in vitro. When HuIFN-β was applied in the ex vivo culture of EPCs, HuIFN-β-transduced EPCs achieved efficient killing of the total population of SPC-A1 cells, indicating a bystander effect was elicited by HuIFN-β-transduced EPCs in vitro. When SCP-A1 cancer cells were coimplanted along with ex vivo cultivated EPCs subcutaneous injection in nude mice, the tumor growth was increased. However, the anti-tumor effect of interferon-beta (IFN-β) offset the tumor-progressive character of EPCs and the tumor growth, and the vascular density of tumor tissues increased by coimplanted EPCs were decreased upon IFN-β treatment. In addition, overall expression levels of vascular endothelial growth factor in tumor tissues were decreased upon IFN-β treatment. Therefore, our results suggest that gene-transfected EPCs could be useful as a tumor-specific drug delivery system.
The relationships of the hyline tribe Dendropsophini remain poorly studied, with most published analyses dealing with few of the species groups of Dendropsophus. In order to test the monophyly of ...Dendropsophini, its genera, and the species groups currently recognized in Dendropsophus, we performed a total evidence phylogenetic analysis. The molecular dataset included sequences of three mitochondrial and five nuclear genes from 210 terminals, including 12 outgroup species, the two species of Xenohyla, and 93 of the 108 recognized species of Dendropsophus. The phenomic dataset includes 46 terminals, one per species (34 Dendropsophus, one Xenohyla, and 11 outgroup species). Our results corroborate the monophyly of Dendropsophini and the reciprocal monophyly of Dendropsophus and Xenohyla. Some species groups of Dendropsophus are paraphyletic (the D. microcephalus, D. minimus, and D. parviceps groups, and the D. rubicundulus clade). On the basis of our results, we recognize nine species groups; for three of them (D. leucophyllatus, D. microcephalus, and D. parviceps groups) we recognize some nominal clades to highlight specific morphology or relationships and facilitate species taxonomy. We further discuss the evolution of oviposition site selection, where our results show multiple instances of independent evolution of terrestrial egg clutches during the evolutionary history of Dendropsophus.
ABSTRACT This research studied the food composition and feeding rhythm of Saurogobio dabryi in the lower reaches of the Jialing River, aimed to explore the seasonal difference of its feeding habits. ...Gut contents of 268 S. dabryi in the downstream (Hechuan section) of the Jialing River were collected seasonally from September 2015 to August 2016. The feeding habits of S. dabryi were studied by microscopic examination, analysis of similarity, and the Amundsen graphical method. A total of 26 food categories were identified, among which algae and organic detritus were the dominant food source for S. dabryi. Animal prey contributed relatively low proportions to the food of S. dabryi. Seasonal variations of food composition of S. dabryi were significant (P<0.05). Hierarchical cluster analysis shows that the food composition in autumn was significantly different from other seasons at a similarity level of 60%. The results indicated that the feeding rhythm of the S. dairyi in the lower reaches of the Jialing River showed significant seasonal changes (P<0.05); The feeding intensity and food amount gradually increased from spring to winter, which may be related to the morphological structure, breeding period, special habitat, and seasonal changes of biological prey of S. dabryi.
The effect of CeO2 loading (1-20wt.%) on the properties and catalytic behaviors of CeO2-Al2O3-supported Pt catalysts on the partial oxidation of methane was studied. The catalysts were characterized ...by SBET, X-ray diffraction (XRD), temperature-programmed reduction (TPR) and oxygen storage capacity (OSC). XRD and TPR results showed that the pretreatment temperature of the support influences on the amount of CeO2 with fluorite structure. The pretreatment temperature of the support and CeO2 loading influenced the morphology of Pt. OSC analysis showed a significant increase in the oxygen storage capacity per weight of CeO2 for samples with high CeO2 loading (12 and 20wt.%). TPR analyses showed that the addition of Pt promotes the reduction of CeO2. This effect was more significant for the catalysts with high CeO2 loading ( > =12wt.%). The dispersion of Pt, measured by the rate of cyclohexane dehydrogenation, increases with increasing of the pretreatment temperature of the support. It was shown that the kind of the support is very important for obtaining of catalysts resistant to carbon formation. The catalysts with high CeO2 loading ( > =12wt.%) showed the highest catalytic activity and stability in the reaction of partial oxidation of methane due to a higher Pt-CeO2 interface.
This work studied the effect of reaction conditions and catalyst reducibility on the performance of the Pt/CeO2 catalyst in the partial oxidation of ethanol. Oxygen storage capacity (OSC) ...measurements allowed evaluation of the oxygen transfer capacity of the catalysts. Metal dispersion was determined through cyclohexane dehydrogenation, a structure-insensitive reaction. Infrared spectroscopy of adsorbed ethanol, temperature-programmed desorption, and temperature-programmed surface reaction of ethanol was performed to establish the reaction mechanism. The low dispersion and low oxygen transfer capacity led to a decrease in both the activity and stability of Pt/CeO 2 catalysts on partial oxidation of ethanol. The higher amount of oxygen near the metal particles promotes the mechanism of carbon removal from the metallic surface, which takes place at the metal-support interfacial perimeter. Moreover, the increase in particle size decreases the metal-support interfacial area, reducing the effectiveness of the mechanism of carbon removal from the metallic surface. Furthermore, the results obtained on partial oxidation of ethanol showed that an increase in the residence time or reaction temperature increased the ethanol conversion and H 2 yield. Regarding selectivity for hydrocarbons and oxygenated products, the production of methane increased and the selectivity for acetaldehyde decreased as the residence time or reaction temperature was increased. At low conversions, the ethanol dehydrogenation dominates, forming acetaldehyde, whereas at high conversions the decomposition of ethanol is favored, producing CH 4 , H2 , and CO. A reaction mechanism is proposed to explain the catalytic tests.
Candidate revolving chiral doublet bands in 119Cs Zheng, K. K.; Petrache, C. M.; Zhang, Z. H. ...
The European physical journal. A, Hadrons and nuclei,
2022/3, Letnik:
58, Številka:
3
Journal Article
Recenzirano
Two rotational bands are identified in
119
Cs, one of which having very similar pattern to that of the strongly-coupled
π
g
9
/
2
404
9
/
2
+
band. The properties of the bands with similar patterns ...extracted from the experimental data are in agreement with a chiral interpretation. Tilted axis cranking covariant density functional theory with pairing correlations and particle-number conserving cranked shell model calculations are employed to determine the deformation and to investigate the band configurations, respectively. It results that the backbending is induced by the rotational alignment of two
h
11
/
2
protons, whose angular momenta reorient from the short to the intermediate axis, in a plane orthogonal to the angular momentum of the strongly-coupled
g
9
/
2
proton which keeps aligned along the long axis. The total spin points in 3D, inducing the breaking of the chiral symmetry. This is the first observation of candidate chiral bands built on a configuration with three protons, one in the strongly coupled
404
9
/
2
+
orbital which does not change orientation with increasing rotational frequency, and two in the
h
11
/
2
orbital which reorients to the rotation axis. The bands are observed in the transient backbending regime, showing that the chirality in nuclei is a general phenomenon, being robust and present not only in nuclei with nearly maximal triaxiality and pure configurations, but also in nuclei with moderate triaxiality and mixed configurations which gradually evolve from one to three-quasiparticle configurations, like in the backbending region.
The impact of historical land use induced land cover change (LULCC) on regional-scale climate extremes is examined using four climate models within the Land Use and Climate, IDentification of robust ...impacts project. To assess those impacts, multiple indices based on daily maximum and minimum temperatures and daily precipitation were used. We contrast the impact of LULCC on extremes with the impact of an increase in atmospheric CO2 from 280 ppmv to 375 ppmv. In general, consistent changes in both high and low temperature extremes are similar to the simulated change in mean temperature caused by LULCC and are restricted to regions of intense modification. The impact of LULCC on both means and on most temperature extremes is statistically significant. While the magnitude of the LULCC-induced change in the extremes can be of similar magnitude to the response to the change in CO2, the impacts of LULCC are much more geographically isolated. For most models, the impacts of LULCC oppose the impact of the increase in CO2 except for one model where the CO2-caused changes in the extremes are amplified. While we find some evidence that individual models respond consistently to LULCC in the simulation of changes in rainfall and rainfall extremes, LULCC's role in affecting rainfall is much less clear and less commonly statistically significant, with the exception of a consistent impact over South East Asia. Since the simulated response of mean and extreme temperatures to LULCC is relatively large, we conclude that unless this forcing is included, we risk erroneous conclusions regarding the drivers of temperature changes over regions of intense LULCC.
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