A new D457 × 7.1 X65ERW oil pipeline leaked twice during the pressure test. The two failed oil pipes belonged to the same batch of products from the same manufacturer. Failure analysis showed that ...the cracks in the 1# and 2# cracking pipes propagated from the outer surface of the pipe wall to the inner surface along the weld fusion line. The inclusion phase distributed in chains in the weld zone is speculated to be the root cause of the cracking in the pressure test. The fitness-for-service of this batch of steel pipes was analyzed using the failure-assessment chart technique. The batch of steel pipes could be used safely under the design pressure of 10 MPa, and the re-evaluation period of three years was recommended for the pipeline based on the fatigue results of the steel-pipe weld zone.
Gastric cancer (GC) is one of the most frequent malignancies worldwide. Long noncoding RNAs (lncRNAs) are found to be largely implicated in various cancers, including GC. However, the function of ...lncRNA VCAN antisense RNA 1 (VCAN‐AS1) in GC remains unclear. Herein, we observed a low level of VCAN‐AS1 in normal gastric tissues through NCBI and UCSC, and that VCAN‐AS1 upregulation in GC tissues was related to poor prognosis by TCGA. Furthermore, VCAN‐AS1 was found markedly enhanced in GC tissues and cell lines, while its upregulation was related with clinical outcomes of GC patients. Besides this, silencing VCAN‐AS1 represses cell proliferation, migration, and invasion but enhances apoptosis. More important, we discovered that VCAN‐AS1 expression was negatively correlated with wild‐type p53 levels in GC tissues and that p53 was negatively modulated by VCAN‐AS1 in GC cells. Furthermore, p53 suppression reversed the repression of VCAN‐AS1 silence on the biological processes of AGS cells. Intriguingly, we identified that both VCAN‐AS1 and TP53 can bind with eIF4A3, one of the core proteins in the exon junction complex. Also, we confirmed that VCAN‐AS1 negatively regulates TP53 expression by competitively binding with eIF4A3. Our findings disclosed that VCAN‐AS1 contributes to GC progression through interacting with eIF4A3 to downregulate TP53 expression, indicating that VCAN‐AS1 is a novel therapeutic strategy for GC treatment.
VCAN antisense RNA 1 (VCAN‐AS1) is overexpressed in GC tissue and cell lines, and GC patients with a higher VCAN‐AS1 suffer worse clinical survival. VCAN‐AS1 facilitates GC progression through the p53‐dependent pathway. VCAN‐AS1 inhibits p53 expression through blocking the binding of eIF4AIII‐assembled exon junction complex (EJC) to TP53 mRNA
We report on the high thermoelectric performance of p-type polycrystalline BiCuSeO, a layered oxyselenide composed of alternating conductive (Cu2 Se2 )2- and insulating (Bi2 O2 )2+ layers. The ...electrical transport properties of BiCuSeO materials can be significantly improved by substituting Bi3+ with Ca2+ . The resulting materials exhibit a large positive Seebeck coefficient of ∼+330 μV K-1 at 300 K, which may be due to the 'natural superlattice' layered structure and the moderate effective mass suggested by both electronic density of states and carrier concentration calculations. After doping with Ca, enhanced electrical conductivity coupled with a moderate Seebeck coefficient leads to a power factor of ∼4.74 μW cm-1 K-2 at 923 K. Moreover, BiCuSeO shows very low thermal conductivity in the temperature range of 300 (∼0.9 W m-1 K-1 ) to 923 K (∼0.45 W m-1 K-1 ). Such low thermal conductivity values are most likely a result of the weak chemical bonds (Young's modulus, E∼76.5 GPa) and the strong anharmonicity of the bonding arrangement (Gruneisen parameter, γ∼1.5). In addition to increasing the power factor, Ca doping reduces the thermal conductivity of the lattice, as confirmed by both experimental results and Callaway model calculations. The combination of optimized power factor and intrinsically low thermal conductivity results in a high ZT of ∼0.9 at 923 K for Bi0.925 Ca0.075 CuSeO.
•Plastic mulch did not affect organic carbon concentration and stock in the top soil.•Plastic mulch increased microbial-derived sugar contents in soil.•Plastic mulch increased soil carbon ...mineralization.•Plastic mulch increased maize root biomass production.•Plastic mulch offset the increased mineralization with enhanced root-derived input.
Plastic-film mulch is widely used to increase soil temperature and reduce water evaporation in vegetable production. In China, it is also extensively used for growing grain crops, especially in temperature and rainfall limited areas. However, it remains unclear whether the technology is sustainable in terms of maintenance of soil organic carbon (SOC) balance. We assessed the effects of plastic-film mulch on the SOC balance in maize (Zea mays L.) production in a range of cold semiarid environments. We imposed four treatments: (i) no plastic-film mulch or straw incorporation, (ii) plastic-film mulch, (iii) straw incorporation in soil without mulch, and (v) straw incorporation plus mulch, in ridge–furrow prepared fields at five sites along a hydrothermal gradient for up to six years. Maize root biomass across sites increased by 23–38% in mulched plots associated with the increase in aboveground biomass, indicating an increased SOC input, compared to that in non-mulched plots. The plastic-film mulch increased SOC mineralization, indicated by the stimulated decomposition of buried maize straw, and a 4–5% reduction in the concentration of light-fraction SOC (<1.8gcm−3), but the total SOC concentration and stock in the 0–0.15m soil layer did not change relative to no mulch after six years of continuous cropping. Plastic-film mulch did not affect the total non-cellulosic sugar content; however, it significantly increased the contribution of microbial-synthesized sugars to the total non-cellulosic sugars, indicating an intensified microbial action on the SOC pool compared to no mulch. Straw incorporation increased the root biomass, light and total SOC concentrations and non-cellulosic sugars, and changed the non-cellulosic sugar composition. We conclude that the increase in soil temperature and moisture by use of plastic-film mulch enhances productivity, but importantly maintains the SOC level in temperature- and rainfall-limited semiarid regions by balancing the increased SOC mineralization with increased root-derived C input.
In this work, two kinds of BN‐nanowires (BNnws): a‐BNnw and d‐BNnw, respectively composed of azo (N−N) and diboron (B−B) bonds, are proposed with the aid of the first‐principles simulations. Their ...structural stabilities are carefully verified from the energetics, lattice dynamics, and thermodynamic perspectives. Similar to the other common boron nitride polymorph, the a‐BNnw and d‐BNnw are semiconductors with relatively wide band gaps of 3.256 and 4.631 eV at the HSE06 level, respectively. The corresponding projected DOS patterns point out that their band edges are composed of different atomic species, which can help with the separation of their excitons. The band gaps can be manipulated monotonically by axial strains within the elastic ranges. The major charge carriers are electron holes. Significantly, a‐BNnw possesses very high carrier mobilities around 0.44×104 cm2 V−1 s−1.
One‐dimensional boron nitride nanowires composed of B−B and N−N bonds are predicted via density functional calculations. The band gaps vary between 1.8 and 3.5 eV under strains, which covers the entire visible light region. Together with high mechanical strengths and charge carrier mobilities, these nanowires can have potential applications in solar cells.
A new multichannel seismic reflection profile collected across the Sichuan Basin in southern China by SINOPROBE images prominent reflectors that originate within the lower crust and penetrate well ...into the underlying mantle. The geometry of these mantle reflectors is very similar to those observed on other deep reflection profiles that have been interpreted as relicts of ancient subduction. Considering the geological history of the basement beneath and surrounding Sichuan Basin and ages of granites encountered in nearby wells, we propose that these newly revealed reflectors are the remnants of Neo-Proterozoic subduction that occurred along the NW margin of the Yangtze Craton. This interpretation is consistent with geochemical studies from a gneissic complex at the west margin of the Sichuan Basin. Moreover, preservation of these reflectors supports the idea that the Sichuan lithosphere served as a consolidated tectonic buttress against which the Tibetan Plateau has impinged to produce the Longmenshan orogenic belt.
•Dipping sub-Moho reflections are imaged beneath Sichuan Basin from SINOPROBE.•The sub-Moho reflections are interpreted as relict subduction.•Relict subduction is Neo-Proterozoic age given nearby geochemical evidence.•Debate about South China tectonic accretion may be solved by this study.•Presence and preservation of fossil subduction shows strength of Sichuan lithosphere.
Due to the disadvantages of poor targeting, slow action, and low effectiveness of current commonly used cancer treatments, including surgery, chemotherapy, and radiotherapy, researchers have turned ...to DNA as a biomaterial for constructing drug delivery nanocarriers. DNA is favored for its biocompatibility and programmability. In order to overcome the limitations associated with traditional drug delivery systems (DDSs), researchers have developed smart-responsive DNA DDSs that can control drug release in response to specific physical or chemical stimuli at targeted sites. In this review, a summary of multiple targeted ligand structures is provided, various shapes of stable DNA nanomaterials, and different stimuli-responsive drug release strategies in DNA DDSs. Specifically, targeted cell recognition, in vivo stable transport, and controlled drug release of smart DDSs are focused. Finally, the further development prospects and challenges of clinical application of DNA nanomaterials in the field of smart drug delivery are discussed. The objective of this review is to enhance researchers' comprehension regarding the potential application of DNA nanomaterials in precision drug delivery, with the aim of expediting the clinical implementation of intelligent DDSs.
•We report a familial cluster of COVID-19 to assess potential transmission of the disease during the incubation period.•A familial cluster of four patients with COVID-19 in Zhoushan, China had ...contact with an asymptomatic family member, who developed symptoms later.•The infectivity during the incubation period for SARS-CoV-2 is a big challenge for controlling the disease.
We report a familial cluster of 2019 novel coronavirus disease (COVID-19) to assess its potential transmission during the incubation period. The first patient in this familial cluster was identified during the presymptomatic period, as a close contact of a confirmed patient. Five family members had close contact with this first patient during his incubation period, with four of them confirmed positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the subsequent sampling tests.
Precise control and accurate understanding of the ordering degree of bimetallic nanocatalysts (BNs) are challenging yet crucial to acquire advanced materials for the oxygen reduction reaction (ORR). ...AuCu BNs with various ordering degrees were synthesized to evaluate the influence of ordering degree on the ORR at a molecular level using in situ Raman spectroscopy. The activity of AuCu BNs was improved by over 2 times after a disorder‐to‐order transition, making the performance of highly ordered AuCu BNs exceed that of benchmark Pt/C. Direct Raman spectroscopic evidence of key intermediate (*OH) demonstrates that the active site is the combination site of Au and Cu. Moreover, two distinct *OH species are observed on the ordered and disordered structure, and the ordered site is more beneficial for ORR due to its lower affinity to *OH. This work deepens the understanding on the important role of ordering degree on BNs and enables the design of improved catalysts.
The critical role of the ordering degree of AuCu bimetallic catalysts was studied in situ by a shell‐isolated nanoparticle‐enhanced Raman spectroscopy satellite strategy and the molecular reaction mechanism is revealed.
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