Search

The small-scale event layers in the continental margin contain abundant dynamic environment information, and pose a challenge to the interpretation of continuous sedimentary records, giving geological significance to their accurate identify and possible genesis. Here, pulsed turbidite layers since the last glacial maximum (LGM) in a gravity core in the northwestern South China Sea (SCS) was analyzed to investigate the precisely identification, possible causes and the role of marine environmental change during the late Quaternary in formation of these small-scale event layers in the SCS. Eight potential pulsed turbidite layers, according to the petrographic characteristics, grain size parameters and element geochemistry, were identified. Meanwhile, indicators including total sulfur (TS)/total organic carbon (TOC) ratio, CaCO3 content, and chromium-reducible sulfur (CRS) revealed these horizons were mostly related to methane seep events. Constrained by foraminifera shells AMS14C results, these events were determined to have occurred from the LGM to early Holocene, Similar records in the northern and southern slopes suggests the universal occurrence of these small-scale layers in the SCS. The comprehensive analysis showed that the development of these event layers over the past 25 ka can be divided into three stages, 25-15.5 ka, 15.5-7 ka and 7 ka to present. Late Quaternary Ocean environment changes, especially sea level and bottom water temperature, controlled the occurrence of regional small-scale event layers in the SCS. The regional scale mechanism is that the pressure and temperature change affect the stability of hydrate and the methane seepage, and thus the strata stability. Corresponding to the lowest, the rapid increase and the highest levels of the sea level and bottom water temperature, the temporal evolution pattern of small-scale event layers in the SCS showed a highest, decreased and lowest frequency, respectively. The linkage between the late Quaternary marine environmental change and turbidite deposition through gas activities in this study can act as a useful reference for further understanding the continental margin sedimentary process.

Additional file 1. Primers designed for amplifying the microsatellites surrounding the TARDBP gene and all the published mutations in the TARDBP gene.

Iron regulatory protein 2 (IRP2) is a key regulator of iron homeostasis and is found to be altered in several types of human cancer. However, how IRP2 contributes to tumorigenesis remains to be elucidated. In this study, we sought to investigate the role of IRP2 in tumorigenesis and found that IRP2 promotes cell growth by repressing TAp63, a member of p53 tumor suppressor family. Specifically, we found that IRP2 overexpression decreased, whereas IRP2 deficiency increased, TAp63 expression. We also showed that the repression of TAp63 by IRP2 was independent of tumor suppressor p53. To uncover the molecular basis, we found that IRP2 stabilized TAp63 mRNA by binding to an iron response element in the 3'UTR of p63 mRNA. To determine the biological significance of this regulation, we showed that IRP2 facilitates cell proliferation, at least in part, via repressing TAp63 expression. Moreover, we found that IRP2 deficiency markedly alleviated cellular senescence in TAp63-deficient mouse embryo fibroblasts. Together, we have uncovered a novel regulation of TAp63 by IRP2 and our data suggest that IRP2 exerts its oncogenic activities at least in part by repressing TAp63 expression. IMPLICATIONS: We have revealed a novel regulation of TAp63 by IRP2 and our data suggest that IRP2 exerts its oncogenic activities, at least in part, by repressing TAp63 expression.

In this paper, the QS-1 sediments (3.64 m long; at 1500 m water depth) collected from the Qiongdongnan Basin were used to analyze the relationship between sedimentary geochemical anomalies and methane seepage. Mo-U covariation, Ce anomaly, and Mg/Ca-Sr/Ca end-member model were analyzed to identify the variations of redox environment and authigenic carbonate precipitation, finally constructing the methane release events in this study area. These observations suggest that: 1) Significant Mo/U enrichments and Ba front indicate the presence of high-flux active methane seepage with SMI of 260 cmbsf in this study area. The depositional environment evolved as oxic-anoxic-reducing-sulfide environment from bottom to top, as evidenced by Mo-U covariation and Ce anomaly; 2) Based on Sr/Ca and Mg/Ca end-member model proposed by Bayon et al. (2007), the high-Mg calcite was the dominant authigenic carbonate currently which usually precipitated behind the methane seep events; and 3) The active cold seep can be divided into three methane release events (MREs): MRE I, the most intense methane seepage occurred at 22.1 ka BP; MRE II, three low-intensity methane seepage occurred at 19.3, 16.5, and 11.3 ka BP, respectively; and MRE III, the continuous methane seep began at 9.3 ka BP until now. The synthesis of geochemical indicators has significant implications for tracing methane seepage of varying intensity and duration.

In this paper, single-phase pyrite with different particle sizes is prepared by hydrothermal method with the reactants of Na2S, S, and FeSO4. Compared with natural pyrite powder, synthesized pyrite nanocubes with small particle sizes and fine distribution have lower resistance, higher specific capacity and power density during the discharging process. The enlarging contacting surface area of pyrite with electrolytes will reduce the concentration polarization caused by the discharging current and improve the utilization efficiency of the pyrite materials. When pulse currents are loaded, compared with natural pyrite single-cell thermal battery, synthetic ones have smaller voltage drops and higher power density during the pulse discharging process. Influences of particle sizes on the thermal stability of the pyrite powders have also been investigated.

A new method to synthesize AgCoO2 delafossite powder with AgNO3 and LiCoO2 by the cation exchange solid state reaction at an atmospheric press has been presented. The effect factors such as moral ratio Ag/Li, reaction time, reaction temperature on the production were discussed systematically and the optimized preparation conditions were obtained. The crystal structure of AgCoO2 from XRD is monoclinic. SEM images showed that AgCoO2 is sheet in shape,single particle size is about 100nm and many single particles swam to form irregular polygon agglomerates.

Single phase pyrite has been successfully prepared via the reaction of FeSO4·7H2O, S and Na2S·9H2O using hydrothermal method. The X-ray powder diffraction measurements confirm the formation of iron disulfides in the pH range of 1-12. Marcasite is formed at pH

The diffusion bonding of TC21 titanium alloy with initial grain size of 2 μm was performed at 780-980 °C for 5-90 min. The microstructure, bonding quality, microhardness and deformation ratio of the joints were analyzed. It is found that the interface bonding ratio can achieve 100% and the deformation ratio can be controlled within 10% when diffusion bonding is performed at 880 °C for 15-30 min. The microhardness of the joints increases with increasing of bonding temperature, but it shows a peak value as the bonding time is prolonged. When the joint is bonded at 880-930°C, fully equiaxed structures are observed, and with increasing of bonding temperature, the sizes of α and β phases are increased; but when bonding temperature is up to 980 °C, fully lamellar structures are obtained. When the joint is bonded at 880 °C for 5-60 min, the size of α and β phases increases with prolonging of bonding time. However, when the bonding time is prolonged to 90 min, the sizes of α and β phases decrease slightly.

Compared to other satellite data, SPOT5 image has obvious advantage in spatial resolution of 2.5 m for panchromatic image satisfied with the demand of land use updating survey at 1: 10,000 scale theoretically. But unfortunately, few studies have been done on area precision of the features. In this paper, one case study was taken in Longxiang section of Zhejiang province in China. A system area precision analysis was performed for the features abstracted from SPOT5 image at 1: 10,000 scale based on the data derived from contemporary aerial survey as true references. Based on antitheses, the area precision was analyzed from the different aspects such as land use type, patch size and combination of land use type. At the same time, the minimum patch area was determined for information extraction from SPOT5 image according to certain precision standard. The results indicate that, on 1:10,000 scale, the patch area precision of each land use type reach about 90% overall, except some upland patches with small area. In fact, for some land use types with frequent conversion, such as residence and construction, the patch average area precision can reach about 95%, the maximum of area precision is about 99%. The study also shows that the bigger the patch area is, the higher the precision can be obtained. Furthermore, it is reliable to extract the patch information of buildings with a high area precision when the changing is between building and other land use types. However, the borderline is unsharp when upland borders upon orchard plot, it is difficult to extract the patch information accurately and the area precision is correspondingly low.