Clayey silt reservoirs bearing natural gas hydrates (NGH) are considered to be the hydrate-bearing reservoirs that boast the highest reserves but tend to be the most difficult to exploit. They are ...proved to be exploitable by the first NGH production test conducted in the South China Sea in 2017. Based on the understanding of the first production test, the China Geological Survey determined the optimal target NGH reservoirs for production test and conducted a detailed assessment, numerical and experimental simulation, and onshore testing of the reservoirs. After that, it conducted the second offshore NGH production test in 1225 m deep Shenhu Area, South China Sea (also referred to as the second production test) from October 2019 to April 2020. During the second production test, a series of technical challenges of drilling horizontal wells in shallow soft strata in deep sea were met, including wellhead stability, directional drilling of a horizontal well, reservoir stimulation and sand control, and accurate depressurization. As a result, 30 days of continuous gas production was achieved, with a cumulative gas production of 86.14 ×104 m3. Thus, the average daily gas production is 2.87 ×104 m3, which is 5.57 times as much as that obtained in the first production test. Therefore, both the cumulative gas production and the daily gas production were highly improved compared to the first production test. As indicated by the monitoring results of the second production test, there was no anomaly in methane content in the seafloor, seawater, and atmosphere throughout the whole production test. This successful production test further indicates that safe and effective NGH exploitation is feasible in clayey silt NGH reservoirs. The industrialization of hydrates consists of five stages in general, namely theoretical research and simulation experiments, exploratory production test, experimental production test, productive production test, and commercial production. The second production test serves as an important step from the exploratory production test to experimental production test.
Organometallic halide perovskite films with good surface morphology and large grain size are desirable for obtaining high‐performance photovoltaic devices. However, defects and related trap sites are ...generated inevitably at grain boundaries and on surfaces of solution‐processed polycrystalline perovskite films. Seeking facial and efficient methods to passivate the perovskite film for minimizing defect density is necessary for further improving the photovoltaic performance. Here, a convenient strategy is developed to improve perovskite crystallization by incorporating a 2D polymeric material of graphitic carbon nitride (g‐C3N4) into the perovskite layer. The addition of g‐C3N4 results in improved crystalline quality of perovskite film with large grain size by retarding the crystallization rate, and reduced intrinsic defect density by passivating charge recombination centers around the grain boundaries. In addition, g‐C3N4 doping increases the film conductivity of perovskite layer, which is beneficial for charge transport in perovskite light‐absorption layer. Consequently, a champion device with a maximum power conversion efficiency of 19.49% is approached owing to a remarkable improvement in fill factor from 0.65 to 0.74. This finding demonstrates a simple method to passivate the perovskite film by controlling the crystallization and reducing the defect density.
Graphitic carbon nitride (g‐C3N4) is incorporated into the perovskite precursor solution to modify the perovskite film by controlling the perovskite crystallization, reducing the intrinsic defect density, and improving the film conductivity. As a result, a champion device with a maximum power conversion efficiency of 19.49% is approached.
This note further investigates the locally and globally adaptive synchronization of an uncertain complex dynamical network. Several network synchronization criteria are deduced. Especially, our ...hypotheses and designed adaptive controllers for network synchronization are rather simple in form. It is very useful for future practical engineering design. Moreover, numerical simulations are also given to show the effectiveness of our synchronization approaches.
Glycolytic enzyme phosphoglycerate mutase 1 (PGAM1) plays a critical role in cancer metabolism by coordinating glycolysis and biosynthesis. A well-validated PGAM1 inhibitor, however, has not been ...reported for treating pancreatic ductal adenocarcinoma (PDAC), which is one of the deadliest malignancies worldwide. By uncovering the elevated PGAM1 expressions were statistically related to worse prognosis of PDAC in a cohort of 50 patients, we developed a series of allosteric PGAM1 inhibitors by structureguided optimization. The compound KH3 significantly suppressed proliferation of various PDAC cells by down-regulating the levels of glycolysis and mitochondrial respiration in correlation with PGAM1 expression. Similar to PGAM1 depletion, KH3 dramatically hampered the canonic pathways highly involved in cancer metabolism and development. Additionally, we observed the shared expression profiles of several signature pathways at 12 h after treatment in multiple PDAC primary cells of which the matched patient-derived xenograft (PDX) models responded similarly to KH3 in the 2 wk treatment. The better responses to KH3 in PDXs were associated with higher expression of PGAM1 and longer/stronger suppressions of cancer metabolic pathways. Taken together, our findings demonstrate a strategy of targeting cancer metabolism by PGAM1 inhibition in PDAC. Also, this work provided “proof of concept” for the potential application of metabolic treatment in clinical practice.
Primary familial brain calcification (PFBC) is a genetically heterogeneous disorder characterized by bilateral calcifications in the basal ganglia and other brain regions. The genetic basis of this ...disorder remains unknown in a significant portion of familial cases. Here, we reported a recessive causal gene, MYORG, for PFBC. Compound heterozygous or homozygous mutations of MYORG co-segregated completely with PFBC in six families, with logarithm of odds (LOD) score of 4.91 at the zero recombination fraction. In mice, Myorg mRNA was expressed specifically in S100β-positive astrocytes, and knockout of Myorg induced the formation of brain calcification at 9 months of age. Our findings provide strong evidence that loss-of-function mutations of MYORG cause brain calcification in humans and mice.
•MYORG is a major causal gene for autosomal recessive PFBC•Specific expression of MYORG suggests astrocyte involves in PFBC•Myorg knockout mice develops calcium deposits in the brain
Yao et al. provide evidence that MYORG is a major causal gene for autosomal recessive PFBC by a comprehensive strategy combining whole-exome sequencing analysis, Sanger sequencing, linkage analysis, RNA expression analysis, and a mouse model.
The reaction of precursors containing both nitrogen and oxygen atoms with NiII under 500 °C can generate a N/O mixing coordinated Ni‐N3O single‐atom catalyst (SAC) in which the oxygen atom can be ...gradually removed under high temperature due to the weaker Ni−O interaction, resulting in a vacancy‐defect Ni‐N3‐V SAC at Ni site under 800 °C. For the reaction of NiII with the precursor simply containing nitrogen atoms, only a no‐vacancy‐defect Ni‐N4 SAC was obtained. Experimental and DFT calculations reveal that the presence of a vacancy‐defect in Ni‐N3‐V SAC can dramatically boost the electrocatalytic activity for CO2 reduction, with extremely high CO2 reduction current density of 65 mA cm−2 and high Faradaic efficiency over 90 % at −0.9 V vs. RHE, as well as a record high turnover frequency of 1.35×105 h−1, much higher than those of Ni‐N4 SAC, and being one of the best reported electrocatalysts for CO2‐to‐CO conversion to date.
A vacancy defect was controllably constructed at the Ni site in a nickel single‐atom catalyst. It shows significantly enhanced electrocatalytic activity and selectivity for CO2‐to‐CO conversion compared with the Ni‐N4 catalyst.
As a highly infectious respiratory tract disease, coronavirus disease 2019 (COVID-19) can cause respiratory, physical, and psychological dysfunction in patients. Therefore, pulmonary rehabilitation ...is crucial for both admitted and discharged patients of COVID-19. In this study, based on the newly released pulmonary rehabilitation guidelines for patients with COVID-19, as well as evidence from the pulmonary rehabilitation of patients with severe acute respiratory syndrome, we investigated pulmonary rehabilitation for patients with COVID-19 having complications, such as chronic pulmonary disease, and established an intelligent respiratory rehabilitation model for these patients.
Natural gas hydrates (NGH) is one of key future clean energy resources. Its industrialized development will help remit the huge demand of global natural gas, relieve the increasing pressure of the ...environment, and play a vital role in the green sustainable growth of human societies. Based on nearly two decades’ studying on the reservoir characteristics in the South China Sea (SCS) and the knowledge of reservoir system, the China Geological Survey (CGS) conducted the first production test on an optimal target selected in Shenhu area SCS in 2017. Guided by the “three-phase control” exploitation theory which focused on formation stabilization, technologies such as formation fluid extraction, well drilling and completing, reservoir stimulating, sand controlling, environmental monitoring, monitoring and preventing of secondary formation of hydrates were applied. The test lasted for 60 days from May 10th when starting to pump, drop pressure and ignite to well killing on July 9th, with gas production of 3.09×105 m3 in total, which is a world record with the longest continuous duration of gas production and maximal gas yield. This successful test brings a significant breakthrough on safety control of NGH production.
The regioselective ring‐opening of 1,2‐ and 1,3‐sulfamidates with fluorine anion is reported. Direct construction of monofluoro‐substituted amines and amino acid derivatives using inexpensive and ...easily available potassium fluoride (KF). The monofluorination process only needs 35 minutes under heating, which will be an attractive route for the synthesis of the PET fluorine‐18 radiotracer. The application of the product can be extended to the construction of fluorinated polypeptides after simple deprotection treatment.
The regioselective ring‐opening of 1,2‐ and 1,3‐sulfamidates with fluorine anion is reported. Construction of monofluoro‐substituted amines and amino acid derivatives is realized by using inexpensive potassium fluoride (KF). The monofluorination process only needs 35 minutes under heating, which will be an attractive new route for the synthesis of the PET fluorine‐18 radiotracer.
NRP1 as multifunctional non-tyrosine-kinase receptors play critical roles in tumor progression. MicroRNAs (miRNAs) are an important class of pervasive genes that are involved in a variety of ...biological functions, particularly cancer. It remains unclear whether miRNAs can regulate the expression of NRP1. The goal of this study was to identify miRNAs that could inhibit the growth, invasion and metastasis of gastric cancer by targeting NRP1 expression. We found that miR-338 expression was reduced in gastric cancer cell lines and in gastric cancer tissues. Moreover, we found that miR-338 inhibited gastric cancer cell migration, invasion, proliferation and promoted apoptosis by targeting NRP1 expression. As an upstream regulator of NRP1, miR-338 directly targets NRP1. The forced expression of miR-338 inhibited the phosphorylation of Erk1/2, P38 MAPK and Akt; however, the expression of phosphorylated Erk1/2, P38 MAPK and Akt was restored by the overexpression of NRP1. In AGS cells infected with miR-338 or transfected with SiNRP1, the protein levels of fibronectin, vimentin, N-cadherin and SNAIL were decreased, but the expression of E-cadherin was increased. The expression of mesenchymal markers in miR-338-expressing cells was restored to normal levels by the restoration of NRP1 expression. In vivo, miR-338 also decreased tumor growth and suppressed D-MVA by targeting NRP1. Therefore, we conclude that miR-338 acts as a novel tumor suppressor gene in gastric cancer. miR-338 can decrease migratory, invasive, proliferative and apoptotic behaviors, as well as gastric cancer EMT, by attenuating the expression of NRP1.
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