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Recently, tremendous research interest has been aroused in clathrate superhydrides. However, their microscopic properties, especially the superconducting (SC) gap and electron-phonon coupling (EPC) strength, are largely unexplored experimentally. Here, we investigate the time-resolved ultrafast spectroscopy of a superconductor LaH 10±δ under an ultrahigh pressure of 165 GPa. By analyzing the ultrafast dynamics of the quasiparticles, we experimentally obtain the SC gap Δ(0) = 53 ± 5 meV, revealing a gap ratio 2Δ(0)/ k B T c  = 5.6 and a gap parameter ϑ  = 1.95. Significantly, we experimentally estimate λ ⟨ Ω 2 ⟩  = (2.4 ± 0.1) × 10 4 (meV) 2 , which corresponds to an EPC strength λ  = 2.58 ± 0.11. These results together provide direct experimental evidence that strong EPC is responsible for the near-room-temperature superconductivity in clathrate superhydrides. Our investigation significantly advances the experimental exploration of superhydrides, and contributes to the ultrafast dynamics investigations of quantum materials under high pressures. Recently, clathrate superhydride superconductors have garnered significant attention. Here the authors measure the electron-phonon coupling strength and superconducting gap of an ultrahigh pressure superconductor LaH 10±δ by ultrafast spectroscopy, revealing a strong coupling nature of the superconductivity.

Atmospheric submicron particulate matter (PM1) is one of the most significant pollution components in China. Despite its current popularity in the studies of aerosol chemistry, the characteristics, sources and evolution of atmospheric PM1 species are still poorly understood in China, particularly for the two harvest seasons, namely, the summer wheat harvest and autumn rice harvest. An Aerodyne Aerosol Chemical Speciation Monitor (ACSM) was deployed for online monitoring of PM1 components during summer and autumn harvest seasons in urban Nanjing, in the Yangtze River delta (YRD) region of China. PM1 components were shown to be dominated by organic aerosol (OA, 39 and 41%) and nitrate (23 and 20%) during the harvest seasons (the summer and autumn harvest). Positive matrix factorization (PMF) analysis of the ACSM OA mass spectra resolved four OA factors: hydrocarbon-like mixed with cooking-related OA (HOA + COA), fresh biomass-burning OA (BBOA), oxidized biomass-burning-influenced OA (OOA-BB), and highly oxidized OA (OOA); in particular the oxidized BBOA contributes ~80% of the total BBOA loadings. Both fresh and oxidized BBOA exhibited apparent diurnal cycles with peak concentration at night, when the high ambient relative humidity and low temperature facilitated the partitioning of semi-volatile organic species into the particle phase. The fresh BBOA concentrations for the harvests are estimated as BBOA = 15.1 × (m/z 60–0.26% × OA), where m/z (mass-to-charge ratio) 60 is a marker for levoglucosan-like species. The (BBOA + OOA-BB)/ΔCO, (ΔCO is the CO minus background CO), decreases as a function of f44 (fraction of m/z 44 in OA signal), which might indicate that BBOA was oxidized to less volatile OOA, e.g., more aged and low volatility OOA (LV-OOA) during the aging process. Analysis of air mass back trajectories indicates that the high BB pollutant concentrations are linked to the air masses from the western (summer harvest) and southern (autumn harvest) areas.

Topological superconductivity is one of most fascinating properties of topological quantum matters that was theoretically proposed and can support Majorana Fermions at the edge state. Superconductivity was previously realized in a Cu-intercalated Bi 2 Se 3 topological compound or a Bi 2 Te 3 topological compound at high pressure. Here we report the discovery of superconductivity in the topological compound Sb 2 Te 3 when pressure was applied. The crystal structure analysis results reveal that superconductivity at a low-pressure range occurs at the ambient phase. The Hall coefficient measurements indicate the change of p-type carriers at a low-pressure range within the ambient phase, into n-type at higher pressures, showing intimate relation to superconducting transition temperature. The first principle calculations based on experimental measurements of the crystal lattice show that Sb 2 Te 3 retains its Dirac surface states within the low-pressure ambient phase where superconductivity was observed, which indicates a strong relationship between superconductivity and topology nature.

The CXCL12/CXCR4 axis has been posited widely to have significant roles in many primary tumors and metastases. It is known that CXCR7 can also be engaged by CXCL12, but the exact function of CXCR7 is controversial. This prompted us to investigate the expression, specific function and signal transduction of CXCR7 in hepatocellular carcinoma (HCC). In this study, CXCR7 and CXCR4 were differentially expressed in nine cell lines of HCC, and that elevated expression of both CXCR7 and CXCL4 were correlated with highly metastatic ability of HCC cells. Moreover, CXCR7 expression was significantly upregulated in metastatic HCC samples compared with the non-metastatic ones by staining of high-density tissue microarrays constructed from a cohort of 48 human HCC specimens. CXCR7 overexpression enhanced cell growth and invasiveness in vitro , and tumorigenicity and lung metastasis in vivo . By contrast, CXCR7 stable knockdown markedly reduced these malignant behaviors. In addition, it was observed that alterations in CXCR7 expression were positively correlated with the phosphorylation levels of mitogen-activated protein kinase (MAPK) pathway proteins. Targeting extracellular regulated kinase pathway by using U0126 inhibitor or using CCX771, a selective CXCR7 antagonist, drastically reduced CXCR7-mediated cell proliferation. Importantly, by using human biotin-based antibody arrays, several differentially expressed proteins were identified in CXCR7-overexpression and depletion groups. Comparative analysis indicated that upstream regulators including TP53 and IL-6 were involved in CXCR7 signal transduction. CXCR7 expression was further proved to regulate expression of vascular endothelial growth factor A and galectin-3, which may contribute to tumor angiogenesis and invasiveness. Consequently, elevated expression of CXCR7 contributes to HCC growth and invasiveness via activation of MAPK and angiogenesis signaling pathways. Targeting CXCR7 may prevent metastasis and provide a potential therapeutic strategy for HCC.

Recently, A 2 B 3 type strong spin orbital coupling compounds such as Bi 2 Te 3 , Bi 2 Se 3 and Sb 2 Te 3 were theoretically predicated to be topological insulators and demonstrated through experimental efforts. The counterpart compound Sb 2 Se 3 on the other hand was found to be topological trivial, but further theoretical studies indicated that the pressure might induce Sb 2 Se 3 into a topological nontrivial state. Here, we report on the discovery of superconductivity in Sb 2 Se 3 single crystal induced via pressure. Our experiments indicated that Sb 2 Se 3 became superconductive at high pressures above 10 GPa proceeded by a pressure induced insulator to metal like transition at ~3 GPa which should be related to the topological quantum transition. The superconducting transition temperature ( T C ) increased to around 8.0 K with pressure up to 40 GPa while it keeps ambient structure. High pressure Raman revealed that new modes appeared around 10 GPa and 20 GPa, respectively, which correspond to occurrence of superconductivity and to the change of T C slop as the function of high pressure in conjunction with the evolutions of structural parameters at high pressures.

Pressure-induced amorphous-to-amorphous configuration changes in Ca-Al metallic glasses (MGs) were studied by performing in-situ room-temperature high-pressure x-ray diffraction up to about 40 GPa. Changes in compressibility at about 18 GPa, 15.5 GPa and 7.5 GPa during compression are detected in Ca 80 Al 20 , Ca 72.7 Al 27.3 and Ca 66.4 Al 33.6 MGs, respectively, whereas no clear change has been detected in the Ca 50 Al 50 MG. The transfer of s electrons into d orbitals under pressure, reported for the pressure-induced phase transformations in pure polycrystalline Ca, is suggested to explain the observation of an amorphous-to-amorphous configuration change in this Ca-Al MG system. Results presented here show that the pressure induced amorphous-to-amorphous configuration is not limited to f electron-containing MGs.

Summary In this study, fish samples were collected by electric fishing gear (2,000 W, 650 V) in May 2015. The length–weight relationships for four fish species from the Muling River in China belonging to two families and four genera were analyzed. A total of 115 specimens were used to estimate the relationship parameters.

Summary Length‐weight relationships were determined for 11 fish species from the tributary of Amur River in Fuyuan, northeastern China. This is the first record of length‐weight relationships for six of these species.

Summary This paper reports the length–weight relationships of 16 fish species belonging to three families and ten genera from the Tarim River in China. Length–weight relationships for ten fish species were unknown to Fishbase, and new maximum lengths are given for six species. The r2 values ranged from 0.972 to 0.995. Values of b varied from 2.79 to 3.49.