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(2-dimethyl amino)ethyl methacrylate (DMA) was co-polymerized with (2-dibutyl amino)ethyl methacrylate (DBA) to form random copolymer P(DMA-co-DBA) with DMA/DBA molar ratios in the range of 9:1 to ...

Lacustrine shale is an important target for the exploration of unconventional oil and gas in China beyond marine shale gas. However, the formation environment of lacustrine shale differs from that of marine shale, resulting in a different reservoir composition, organic matter, oil and gas content, and hydrocarbon mobility. In this study, the Chang 7 shale of the Yanchang Formation in the Ordos Basin was used to analyze the effect of volcanic activity on the paleoproductivity and preservation conditions during the formation of lacustrine shale. The results show that algae and bacteria were developed before the eruption. After the eruption, the number of bacteria declined, but the increased prosperity of algae reflects that the volcanic activity enhanced ancient productivity. The sulfate generated by volcanic activity promotes bacterial sulfate reduction, and the produced H2S leads to a strong reducing environment in the waterbody, which is conducive to the preservation of organic matter. Organic geochemical analysis shows that the black shale in the shale strata has a high total organic carbon (TOC) content and strong hydrocarbon generation potential, whereas the tuff has a low TOC content and can scarcely generate hydrocarbons, indicating that the tuff deposited by volcanic activity cannot be considered as effective source rock. In terms of storage space, shale is mainly laminar and dispersed, and it includes organic and inorganic pores. The development of organic pores is affected by thermal maturity, whereas inorganic pores mainly occur between detrital particles and crystals. Tuff is mainly supported by heterogeneous matrix and associated with alteration. Its pores include inter- and intragranular mineral pores. The development of tight sandstone pores is affected by compaction, cementation, and dissolution, which mainly consist of intra- and intergranular pores. The Chang 7 lacustrine shale generally contains oil, but different lithologies have different oil drainage efficiencies. Sandstone and shale exhibit the best and worst oil drainage efficiency, respectively. It is mainly affected by the pore size distribution, fluid properties, and rock wettability. Therefore, the development of shale oil should mainly focus on lacustrine shale formations with interbeds. The mutual dissolution of organic matter and hydrocarbons in the shale section leads to the poor mobility and difficult development of hydrocarbons.

Post-translational modification (PTM) on protein plays important roles in the regulation of cellular function and disease pathogenesis. The systematic analysis of PTM dynamics presents great opportunities to enlarge the target space by PTM allosteric regulation. Here, we presented a framework by integrating the sequence, structural topology, and particular dynamics features to characterize the functional context and druggabilities of PTMs in the well-known kinase family. The machine learning models with these biophysical features could successfully predict PTMs. On the other hand, PTMs were identified to be significantly enriched in the reported allosteric pockets and the allosteric potential of PTM pockets were thus proposed through these biophysical features. In the end, the covalent inhibitor DC-Srci-6668 targeting the PTM pocket in c-Src kinase was identified, which inhibited the phosphorylation and locked c-Src in the inactive state. Our findings represent a crucial step toward PTM-inspired drug design in the kinase family.

Waste bamboo-derived activated carbon (BAC), biomass char (BBC), and nitric acid-modified BACN and BBCN supports as well as commercial activated carbon (AC) and corresponding ACN were prepared for comparative study. Their denitrification performance in 100–250 °C decreased as BACN > ACN > BBCN > BAC > AC > BBC. BACN and ACN were separately loaded with different MOx (M = Mn, Ce, Fe, Cu, V) by wet impregnation. M/BACN showed slightly higher NO conversion than corresponding M/ACN. Mn/BACN exhibited the best denitrification performance with NO conversion of 92% at 200 °C. The physicochemical properties of supports and catalysts were characterized by BET, SEM-EDS, FTIR, XRD, and XPS. The results suggested that BAC was most sensitive to HNO3 modification, thereby BACN possessed much more surface functional groups. This was the main reason for BACN exhibiting the best denitrification performance among the supports. Loading metal oxides introduced more strong active sites sharply increasing the catalytic activity, even though decreased the surface area and decomposed a few surface functional groups. Mn/BACN mainly followed the L–H mechanism at low temperature. Rich surface functional groups on BACN could promote the adsorption and activation of NH3 and NO accelerating the reaction in L–H mechanism.

An accurate prediction of the hydrogen behaviors in the accident and management process is a crucial topic for both the hydrogen safety assessment and safety analysis in the confined enclosure like the containment of the nuclear power plant (NPP). Hence, the hydrogen behaviors including the transient light gas release, stratification and dissolution in the TH22 test facility for the NPP containment are analyzed and compared using the 3-D CFD code GASFLOW-MPI in this study. In this paper, the light gas helium is adopted as a substitute for the hydrogen in the calculations in accordance with the experiment. Firstly, the detached eddy simulation (DES) turbulence model, 3-D numerical model and experiment setup are introduced. Then, the hydrogen behaviors with the GASFLOW-MPI including the light gas release, stratification and dissolution are analyzed and validated with the experiment data. In addition, the velocity profiles, light gas concentrations, dimensionless numbers and temperature distributions are evaluated for the characteristics of the hydrogen behaviors. The results indicate that the calculation results agree well with the experiment data. Foremostly, the relative errors between the calculation results and experiment data during the phase of the dissolution of the light gas cloud are within 11.9%. Meanwhile, the relative errors of the time for the complete dissolution during the phase of the dissolution of the light gas cloud are within 5.0%. For the light gas release and stratification phase, the jet flow dominates as the Froude (Fr) number exceeds 10 during the time t = 600 s–800 s. Additionally, the time averaged centerline velocity and light gas concentration after the potential core region decay with a slop of 1/z which coincide with the theoretical jet limit. Lastly, the light gas concentrations and temperature distributions in all three phases are captured clearly with the GAFLOW-MPI. It demonstrates that the GASFLOW-MPI can accurately described the details of the related hydrogen behaviors in the accident and management process in the confined enclosure like the NPP. This paper can provide guidance for the numerical computation of the hydrogen safety issues in the confined space.

Two structural isomers of highly conjugated (bisthiophene)benzene carbazoles were designed and synthesized to study the effect of the substitution pattern on their liquid crystalline behavior, tran...

The shuttle effect of polysulfides severely blocks the cycling performance and commercial application of lithium–sulfur (Li–S) batteries. Recently, metal–organic frameworks (MOFs) with abundant porosity, nanometer cavity size, and high specific surface areas have been considered to be an effective material in inhibiting polysulfide diffusion. However, the insulation properties of MOFs and the reuse of dissolved polysulfides are still challenging. Hence, in this study, a fluorine doped ZIF-8 derived porous carbon is designed and applied as a membrane modifier to mitigate the shuttle effect and maximize reuse of the dissolved polysulfides. A comparative study of a bare membrane, ZIF-8 carbonized material (N–C-1000) coated membrane and fluorine doped ZIF-8 derived porous carbon (F–N–C-1000) coated membrane was performed. The experimental results prove that a layer of ZIF-8 derived porous carbon coated membrane does improve the capacity and cycling stability. The results also show that the optimal candidate with enhanced capacity and cycling stability should be mainly ascribed to physical adsorption (abundant porosity), chemical adsorption (fluorine and nitrogen doping) and even reuse of dissolved polysulfides by the modified membrane.

Novel heterocyclic liquid crystalline semiconductors incorporating fused thiazolo[5,4-d]thiazole (N, S), thiophene (S), pyridine (N), and/or alkoxy (O) units have been synthesised via simple and hi...

In this study, a gradient material for shielding neutrons and gamma rays was developed, which consists of epoxy resin, boron carbide (B4C), lead (Pb) and a little graphene oxide. It aims light weight and compact, which will be applied on the transportable nuclear reactor. The material is made up of sixteen layers, and the thickness and components of each layer were designed by genetic algorithm (GA) combined with Monte Carlo N Particle Transport (MCNP). In the experiment, the viscosities of the epoxy at different temperatures were tested, and the settlement regularity of Pb particles and B4C particles in the epoxy was simulated by matlab software. The material was manufactured at 25 °C, the Pb C and O elements of which were also tested, and the result was compared with the outcome of the simulation. Finally, the material's shielding performance was simulated by MCNP and compared with the uniformity material's. The result shows that the shielding performance of gradient material is more effective than that of the uniformity material, and the difference is most noticeable when the materials are 30 cm thick.

A series of CeO2 photocatalysts were synthesized through the molten salt method. The photocatalytic activity was evaluated through the degradation of methyl orange (MO). Systematic characterizations including X-ray diffraction, Scanning electron microscopy, Fourier transformed infrared, X-ray photoelectron spectroscopy, Raman spectroscopy, electron spin-resonance spectroscopy, UV–vis diffuse reflectance spectroscopy, photoluminescence spectrometry, photocurrent response and electrochemical impedance spectroscopy were conducted to study the as-prepared CeO2 samples. It was found that, under ultraviolet light irradiation, the apparent rate constants of CeO2 prepared at 800 °C for degradation of MO was about 3.4 times higher than CeO2 prepared at 500 °C. CeO2 prepared at 800 °C held the higher oxygen vacancies concentration. According to the trapping experiments, it was demonstrated that photo-generated holes played a dominant role in this photocatalytic system. Furthermore, the possible photocatalytic mechanism which showed the roles of photo-generated holes and oxygen vacancies was proposed.

Several oligomers (MWs > 1000 g mol−1) with highly rigid and conjugated aromatic cores, incorporating 1,4-disubstituted phenylene, 2,7-disubstituted fluorene, 1,4-disubstituted thiophene and/or 2,7...

Novel symmetrical carbazole-thieno[3,4-c]pyrrole-4,6-dione-carbazoles (Carbazole-TPD-Carbazole) were designed and synthesised as donor–acceptor-donor (D-A-D) materials. The correlations between the...

Two structural isomers of alkyl-substituted tri-carbazoles were synthesised to study the effect of the substitution pattern on their liquid crystalline behaviour and conductivity and performance in...

The polymer-matrix nuclear radiation shielding material is an important component of nuclear power plants. However, its mechanical properties and shielding performance gradually deteriorate due to the long-term synergy of nuclear radiation and thermal effects, which brings hidden dangers to the safe operation of the device. Based on this problem, this article makes a comprehensive review. First, the degradation of mechanical properties and shielding performance of polymer-matrix nuclear radiation materials in service is briefly described. Then, the research methods adopted by scholars to study the change law of properties and performance are introduced, and the main existing difficulties encountered by the study are summarized. Finally, the physical mechanism of the change of material properties is explained in detail, and a reference approach to solving the problem is proposed.

Background: Farmers harvest two batches fruits of Lemons (Citrus limon L. Burm. f.) i.e., spring flowering fruit and autumn flowering fruit in dry-hot valley in Yunnan, China. Regular lemons harvested in autumn have smooth skin. However, lemons harvested in spring have rough skin, which makes them less attractive to customers. Furthermore, the rough skin causes a reduction in commodity value and economical losses to farmers. This is a preliminary study that investigates the key transcriptomic and metabolomic differences in peels of lemon fruits (variety Yuning no. 1) harvested 30, 60, 90, 120, and 150 days after flowering from the same trees in different seasons.Results: We identified 5,792, 4,001, 3,148, and 5,287 differentially expressed genes (DEGs) between smooth peel (C) and rough peel (D) 60, 90, 120, and 150 days after flowering, respectively. A total of 1,193 metabolites differentially accumulated (DAM) between D and C. The DEGs and DAMs were enriched in the mitogen-activated protein kinase (MAPK) and plant hormone signaling, terpenoid biosynthesis, flavonoid, and phenylalanine biosynthesis, and ribosome pathways. Predominantly, in the early stages, phytohormonal regulation and signaling were the main driving force for changes in peel surface. Changes in the expression of genes associated with asymmetric cell division were also an important observation. The biosynthesis of terpenoids was possibly reduced in rough peels, while the exclusive expression of cell wall synthesis-related genes could be a possible reason for the thick peel of the rough-skinned lemons. Additionally, cell division, cell number, hypocotyl growth, accumulation of fatty acids, lignans and coumarins- related gene expression, and metabolite accumulation changes were major observations.Conclusion: The rough peels fruit (autumn flowering fruit) and smooth peels fruit (spring flowering fruit) matured on the same trees are possibly due to the differential regulation of asymmetric cell division, cell number regulation, and randomization of hypocotyl growth related genes and the accumulation of terpenoids, flavonoids, fatty acids, lignans, and coumarins. The preliminary results of this study are important for increasing the understanding of peel roughness in lemon and other citrus species.

Tyrosinase is an oxidase that is the rate-limiting enzyme for controlling the production of melanin in the human body. Overproduction of melanin can lead to a variety of skin disorders. Calycosin is an isoflavone from Astragali Radix, which is a traditional Chinese medicine that exhibits several pharmacological activities including skin whitening. In our study, the inhibitory effect of calycosin on melanin production is confirmed in a zebrafish in vivo model by comparing with hydroquinone, kojic acid, and arbutin, known as tyrosinase inhibitors. Moreover, the inhibitory kinetics of calycosin on tyrosinase and their binding mechanisms are determined using molecular docking techniques, molecular dynamic simulations, and free energy analysis. The results indicate that calycosin has an obvious inhibitory effect on zebrafish pigmentation at the concentration of 7.5 μM, 15 μM, and 30 μM. The IC50 of calycosin is 30.35 μM, which is lower than hydroquinone (37.35 μM), kojic acid (6.51 × 103 μM), and arbutin (3.67 × 104 μM). Furthermore, all the results of molecular docking, molecular dynamics simulations, and free energy analysis suggest that calycosin can directly bind to the active site of tyrosinase with very good binding affinity. The study indicates that the combination of computer molecular modeling and zebrafish in vivo assay would be feasible in confirming the result of the in vitro test and illustrating the target-binding information.

This paper presents characteristics of the HEMP radiation field on a typical transport aircraft using the frequency sweep method. Firstly, the characteristics of the HEMP field are analyzed. Then, various parameters including the electric field strength and magnetic field strength distribution are calculated using Altair FEKO software. Afterwards, the electric field strength distributions of three layers (top layer, inner layer and bottom layer) are calculated and analyzed. The results indicate that the HEMP induced field is affected by the aircraft body. The induced electric field strength E(t) varies greatly at different positions. Nevertheless, the peak value of E(t) is usually greater than the initial peak value of electric field strength E0. Such a study can provide guidance and insight into the protection design of the HEMP of the aircraft.

Washing method by sulfuric acid was investigated in the context of deactivation and regeneration mechanism of arsenic deactivated catalyst over V2O5-WO3/TiO2 catalyst. The physical and chemical properties changes for catalysts were characterized by XRD, SEM, BET, Raman, XPS, NH3-TPD and in situ DRIFT, therein including morphology, structure, chemical states, surface acidity and functional groups. The results indicated that arsenic species mainly consisted of As2O5 on the arsenic poisoned catalyst surface. It increased N2O formation due to high active oxygen ratio of poisoned catalyst. After regeneration, the N2O formation was reduced. Arsenic oxides covering on catalyst surface could be almost wipe off with sulfuric acid. As-OH group disappeared, and the Bronsted and Lewis acid sites were re-exposed. Moreover, a new Bronsted acid sites (S-OH) was formed by chelating bidentate sulfates (SO42−) since it introduced S=O into anatase TiO2 lattice. However, some vanadium species were lost and the remaining species tended to form V4+, the activity had an apparent decrease in the temperature range of 300–400 °C.

Aim Excessive exposure to 5-hydroxymethylfurfural (5-HMF), which is a common impurity in various sugar-containing products, induces serious side effects. Our previous study revealed that 5-HMF exerted immune sensitizing potential when injected into rodents. In this study, we explored 5-HMF mediated anaphylactoid reactions and its underlying molecular mechanisms. Methods We investigated anaphylactoid reactions in Brown Norway (BN) rats and Institute of Cancer Research (ICR) mice to identify 5-HMF mediated in vivo anaphylactoid reactions. RBL-2H3 and P815 cell degranulation models were also established, and degranulation, enzyme-linked immunosorbent, filamentous actin (F-actin) microfilament staining, and western blot assays were performed in these cells. Results We showed that 5-HMF induced anaphylactoid reactions by increasing blood vessel permeability in mice, and significantly elevating histamine (His) and glutathione peroxidase-1 (Gpx-1) levels in rat serum. Moreover, after incubation with 5-HMF, β-hexosaminidase (β-Hex), His, IL-4 and IL-6 levels were all significantly increased, thereby inducing cellular degranulation in RBL-2H3 and P815 cells. Finally, 5-HMF also upregulated Lyn, Syk, p38 and JNK protein phosphorylation levels. Conclusions Our findings suggest that 5-HMF induces anaphylactoid reactions both in vivo and in vitro, therefore 5-HMF limits in sugar-containing products should receive more regulatory attention.

Initial neutrons are produced by accelerator-driven neuron sources, and in order to gain various energy ranges to realize all kinds of applications of the neutrons, specially designed neutron sources are required. Therefore, in this research, a method for designing neutron sources with wanted energy ranges is developed. Through a special design of the structure and components of the materials of the neutron source, it is able to gain the intended neutrons. In the investigation, the method is first applied to an initial neutron source for gaining 0.025 eV to 1.0 eV neutrons, and the initial neutrons are produced by proton bombing the beryllium (Be) target, which is simulated by GEANT4. In the simulation, the thickness of moderator materials including polythene (PE), H2O, and CH4 is carefully designed for the neutron source, and since the multilayer and composite material has the potential of improving the neutrons, the structure and components of two models for complex materials are also devised accordingly. Finally, this method is applied to a compact neutron source (CANS) for gaining thermal neutrons.

Calculation of isotopic distribution is a valuable but challenging task in biological mass spectrometry. An algorithm to simulate both isotope aggregated and fine structure is proposed in this paper. The algorithm generates isotopic distribution of a given molecular formula by vector manipulation and change-making strategy based on the concept of denomination system. Additional feature of the algorithm can provide isotope fine structure within an interested m/z window. The performance of the algorithm is evaluated by a number of testing molecules. It is shown that the algorithm is accurate and efficient, providing an alternative solution to the conundrum of isotopic distribution calculation. The program has been implemented as an interactive Matlab package, an independent GUI software, and an open-source Python package, which can be conveniently downloaded and installed.

V2O5-WO3/TiO2 catalyst has been widely used in industry. Alkali metals would cause the deactivation of V2O5-WO3/TiO2 catalyst. In this paper, the poisoning deactivation of NaCl and Na2O on V2O5-WO3/TiO2 catalyst was compared. The properties of the catalysts were characterized by BET, XPS, H2-TPR, NH3-TPD and in situ DRIFTS. It was found the addition of NaCl, Na2O affected the structure, redox properties and acid sites of V2O5-WO3/TiO2 catalyst. Na+ would react with V OH to form V O Na+ destroying the structure of Bronsted sites and affect the adsorption of NH3 on the Lewis acid to restrain the generation of V4+ NH2 to decrease the SCR activity, occupying the oxygen vacancy made a decline in chemisorbed oxygen. The poisoning effect of NaCl was stronger than that of Na2O, even if the property of weak-chemisorption of NaCl is stronger and possessed more V5+ species. There is a reason that NaCl provided HCl and then reacted with VO2 to form Cl V O Cl OH to adsorb NH3. However, Cl V O Cl OH cannot make the catalysis selectively generate nitrogen and water.

The Junggar Basin of NW China is representative in containing oil and gas seeps worldwide as there are a wide variety of oil and gas seeps over a large area. However, the genesis of these seeps remains poorly known, limiting the understanding of their implications for petroluem geology and hydrocarbon exploration. Here, we investigate 26 samples of oil and gas seeps from nine outcrops within five areas along the margins of the Junggar Basin to determine the geochemical characteristics of the hydrocarbons, constrain their genesis, and discuss future exploration strategies. Results indicate one type of gas seeps and five types of oil seeps. The gas seeps are derived from low-maturity Jurassic source rocks and occur in the Wusu and Dushanzi areas in the western segment of the southern basin. Type 1 oil seeps, sourced from lower Permian rocks (P1f), occur on the northwestern margin. Type 2 oil seeps, derived from middle Permian source rocks (P2l/P2p), occur on the eastern segment of the southern margin and eastern margin of the Junggar Basin. Type 3 oil seeps, with Jurassic source rocks, occur in the Qigu area in the middle segment of the southern basin. Type 4 oil seeps, with Cretaceous source rocks, occur in the Anjihai and Huoerguosi areas within the middle segment of the southern basin. Type 5 oil seeps mainly have Paleogene source rocks with a minor contribution from Jurassic rocks and occur in the Wusu and Dushanzi areas in the western segment of the southern basin with the single-type gas seeps. These results indicate the presence of lacustrine hybrid petroleum systems within the Junggar Basin with complex oil and gas sources and migration-accumulation. Six potential areas along the basin margin were proposed for exploration in the future.

Owing to the integration of microfiber couplers (MFCs), polyvinyl alcohol overlay (PVA) material and U-shaped structure, a novel humidometer depended on unsymmetrical U-shaped twisted MFC is reported in this work. The special MFC sensing structure is formed by two microfiber tapers, which attach together under the action of van der Waals force and electrostatic attractive force, therefore it is convenient to adjust the coupling length according to the design requirements. In addition, a layer of PVA material with tens of nanometers is covered on the coupling region by the coating method "first in the middle and then on both sides". Finally, the U-shaped MFC is fabricated. This sensing structure possesses a large detection range (18%–95%RH) at the laboratory temperature. The demonstrated sensing structure with larger effective coupling length shows that the humidity sensitivity is 100.2 pm/%RH with a very good linearity (R2 = 0.9961). The RH sensitivity is enhanced by ˜2 times compared with that of the sensor with shorter effective coupling length. This sensor also shows other advantages, including high reversibility, repeatability and low temperature cross-sensitivity.

Background: Aloe barbadensis Miller 1768, A. vera L. var. chinensis (Haw.) Berger 1908, A. ferox Miller 1768, and A. arborescens Miller 1768 are the most widely cultivated species of Aloe and are used in Asia along with 400 other Aloe species worldwide because of their potent and potential bioactivity. Objective: The objective was to analyze and compare the soluble proteins of four commonly used medicinal Aloe species. Methods: Aloe protein samples were obtained by TCA/acetone-saturated phenol-methanol/ammonium acetate combined extraction (phenol extraction), and then were analyzed by sodium dodecyl sulfate–polyacrylamide gel electrophoresis and two-dimensional gel electrophoresis. Finally, the differentially expressed proteins of four Aloe species were identified by matrix-assisted laser desorption ionization–time-of-flight–MS analysis. Results: The phenol extraction method was the most suitable method for the protein extraction of Aloe. Fifty differentially expressed proteins in four Aloe species were successfully identified and divided into eight functional categories. Furthermore, Malate dehydrogenase and ran-binding protein in A. barbadensis, cytoskeletal-related protein tubulin in A. vera var. chinensis and auxin-induced protein PCNT-115 in A. arborescens are closely related to their morphological characteristics. Conclusions: There are differences in the soluble proteins of the four Aloe species. Those proteins, related to the difference of their morphology of Aloe, might be used to identify different species. Highlights: Fifty differentially expressed proteins in four medicinal Aloe species were identified, and these proteins were classified into eight categories according to their biological functions. Four special proteins closely related to the morphological characteristics of Aloe were found and might be used to identify these four Aloe species.

Si is one of the most attractive anode materials because of its extremely high theoretical capacity. In this study, we find that the (111) plane of crystalline Si in the anode is still present after 100 cycles and infer that it is the intercalation site of Li+ ions. We believe that Li+ ions are inserted into the tetrahedral sites of crystalline Si, and the (111) plane of Si collapses; meanwhile, expansion parallel to 〈220〉 crystal orientation occurs. After full lithiation, the crystalline Si is converted to amorphous silicon. In a Si/ composite anode, although the addition of amorphous carbon may improve the cycling performance of Si anode, the activation process is prolonged as the amount of amorphous carbon increased. We determine that amorphous carbon may reduce the diffusion of Li+, which increases the overpotential and results in the lower formation of the saturated Li/Si alloy.

Paleosol carbonates were found in the Erlongkou section at the top of the Changhsing Formation in Chongqing, southwestern China. Detailed petrology study suggested that these paleosol carbonates have typical pedogenic structures and fabrics. Conodont biostratigraphy, volcanic ash zircon dating, and stratigraphic carbon isotopes indicated that the paleosol carbonates formed at the end of Permian (252.3 ± 1.0 Ma). Geochemical results indicate two different provenances for the paleosol (i.e., the micrite of the Changhsing Formation and volcanic ash). The calcretes and carbonates in the paleosol are pedogenic calcites that precipitated under well-drained conditions, and they are free of carbonate debris from the bedrocks. Atmospheric CO2 concentrations (pCO2) estimated based on the model of Cerling (1999) suggested that there was greenhouse paleoclimates with a transient fluctuation in pCO2 at the end of the Permian.

In this research, a high-boron-content composite material with both neutron and γ rays shielding properties was developed by an optimized design and manufacture. It consists of 304 stainless steel as the matrix and spherical boron carbide (B4C) particles as the functional particles. The content of B4C is 24.68 wt%, and the particles’ radius is 1.53 mm. The density of the newly designed material is 5.17 g·cm−3, about 68.02% of that of traditional borated stainless steel containing 1.7 wt% boron, while its neutrons shielding performance is much better. Firstly, focusing on shielding properties and material density, the content and the size of B4C were optimized by the Genetic Algorithm (GA) program combined with the MCNP program. Then, some samples of the material were manufactured by the infiltration casting technique according to the optimized results. The actual density of the samples was 5.21 g cm−3. In addition, the neutron and γ rays shielding performance of the samples and borated stainless steel containing 1.7 wt% boron was tested by using an 241Am–Be neutron source and 60Co and 137Cs γ rays sources, respectively, and the results were compared. It can be concluded that the new designed material could be used as a material for nuclear power plants or spent-fuel storage and transportation containers with high requirements for mobility.

Pancreatic cancer (PC) is a malignant tumor disease, whose molecular mechanism is not fully understood. Sodium channel epithelial 1α subunit (SCNN1A) serves an important role in tumor progression. The current study explored the role of homeobox D9 (HOXD9) and SCNN1A in the progression of PC. The expression of SCNN1A and HOXD9 in PC samples was predicted on online databases and detected in PC cell lines. The association between SCNN1A expression and PC prognosis was examined by the Gene Expression Profiling Interactive Analysis, The Cancer Genome Atlas and Genotype‑Tissue Expression databases and by a Kaplan‑Meier plotter. Subsequently, the biological effects of SCNN1A on PC cell growth, colony formation, migration and invasion were investigated through RNA interference and cell transfection. Next, the expression of E‑cadherin, N‑cadherin, Vimentin and Snail was detected by western blotting to discover whether HOXD9 dysregulation mediated PC metastasis. Binding sites of HOXD9 and SCNN1A promoters were predicted on JASPAR. Reverse transcription‑quantitative PCR and western blotting were used to detect the expression level of SCNN1A following interference and overexpression of HOXD9. Luciferase assay detected luciferase activity following interference with HOXD9 and the transcriptional activity of SCNN1A following binding site deletion. High expression of SCNN1A and HOXD9 in PC was predicted by online databases, signifying poor prognosis. The present study confirmed the above predictions in PC cell lines. Knockdown of SCNN1A and HOXD9 could effectively inhibit the proliferation, migration, invasion and epithelial‑mesenchymal transition of PC cells. Furthermore, HOXD9 activated SCNN1A transcription, forming a feedback regulatory loop. HOXD9 was demonstrated to activate SCNN1A and promote the malignant biological process of PC.

Organic matter (OM), composed of various macerals, has a strong influence on the enrichment of shale gas. Nevertheless, the connection between OM-hosted pore structure and maceral type is not yet fully understood because of the difficulty to identify the maceral types by traditional scanning electron microscope (SEM). Using a combination of the reflected light microscopy, focused ion beam SEM (FIB-SEM), and Raman spectrum, three maceral types, including alginite, graptolite, and solid bitumen, are identified in the Longmaxi Shale of the Sichuan Basin. The alginate is characterized by the linear arrangement of OM-hosted pores due to the inherited biological structure of benthic algae. Pores in the structureless solid bitumen are randomly distributed with the highest abundance. The graptolite containing pore rarely is unfavorable for the pore generation but can be a good proxy for thermal maturity. Variation in thermal maturity levels accounts for the change of total pore volume in a given marcel type in the Longmaxi Shale obtained from different shale gas fields.

DNA methyltransferases (DNMTs) including DNMT1 are a conserved family of cytosine methylases that play crucial roles in epigenetic regulation. The versatile functions of DNMT1 rely on allosteric networks between its different interacting partners, emerging as novel therapeutic targets. In this work, based on the modeling structures of DNMT1-ubiquitylated H3 (H3Ub)/ubiquitin specific peptidase 7 (USP7) complexes, we have used a combination of elastic network models, molecular dynamics simulations, structural residue perturbation, network modeling, and pocket pathway analysis to examine their molecular mechanisms of allosteric regulation. The comparative intrinsic and conformational dynamics analysis of three DNMT1 systems has highlighted the pivotal role of the RFTS domain as the dynamics hub in both intra- and inter-molecular interactions. The site perturbation and network modeling approaches have revealed the different and more complex allosteric interaction landscape in both DNMT1 complexes, involving the events caused by mutational hotspots and post-translation modification sites through protein-protein interactions (PPIs). Furthermore, communication pathway analysis and pocket detection have provided new mechanistic insights into molecular mechanisms underlying quaternary structures of DNMT1 complexes, suggesting potential targeting pockets for PPI-based allosteric drug design.

Purpose We aim to investigate the risk factors associated with the prognosis of proliferative diabetic retinopathy (PDR) after a sequential treatment of intravitreal injection of bevacizumab (IVB) and pars plana vitrectomy (PPV). Methods In this cohort study, 63 eyes from 55 patients (21 females) diagnosed with PDR, who needed PPV for non-clearing vitreous hemorrhage or fibrovascular membrane proliferation were enrolled. All the eyes underwent IVB followed by PPV. Anterior chamber tap was performed at the beginning of both procedures to evaluate the concentration of vascular endothelial growth factor (VEGF), interleukin (IL)-6, IL-8, and monocyte chemoattractant protein (MCP)-1. Results Forty-seven patients (54 eyes) were followed over six months, averaging 12±5 (6–19) months. The concentration of VEGF significantly decreased after IVB (P Conclusions MCP-1 was a predictor for the unfavorable visual outcome of PDR after IVB pretreatment and PPV.

Power-to-Gas technologies could play an important role in future energy systems, since they make it possible to store surplus electric energy from fluctuating renewable energy sources such as solar and wind. In Power-to-Gas concepts, the first step towards storage is the production of H2 by electrolysis, a possible further step is methanation. The Engler-Bunte-Institute, Fuel Technology at Karlsruhe Institute of Technology is conducting research on catalytic methanation in slurry bubble column reactors, which represent a highly load flexible reactor technology. To obtain experimental data at a semi-industrial scale a methanation pilot plant was built and commissioned. The plant is equipped with various safety valves, which may release the hazardous gases H2, CO and CH4 in the chemical reactor into the environment in the unintended case of overpressure, which may lead to a flammable and/or toxic cloud, threatening the safety of the workers and other humans near the plant. In this work, the safety evaluation of the accidental release in the methanation plant is performed using the numerical tool GASFLOW-MPI. Both toxicity and flammability of the hazardous gas cloud are analyzed and discussed. A local-global two-step simulation strategy, including a local computational model and a global computational model, is employed to calculate the hazardous gas dispersion efficiently and accurately. In the first step, a local detailed computational model with fine mesh is used to calculate the release mass flow through the exhaust tube and the complicated shock waves directly without any further assumption model such as the notional nozzle model. In the second step, a large-scale model with the relatively coarse mesh is chosen to efficiently predict the hazardous gas dispersion around the entire methanation plant. Moreover, the performances of two different types of exhaust pipes are compared and discussed, and the recommended exhaust pipe design is provided. The simulation results show that version B of the exhaust tubes is more recommendable from the viewpoint of safety.

No comment; International audience; Quantum-state control of reactive systems has enabled microscopic probes of underlying interaction potentials and the alteration of reaction rates using quantum statistics. However, extending such control to the quantum states of reaction outcomes remains challenging. Here, we realize this goal by utilizing the conservation of nuclear spins throughout the reaction. Using resonance-enhanced multiphoton ionization spectroscopy to investigate the products formed in bimolecular reactions between ultracold KRb molecules we find that the system retains a near-perfect memory of the reactants’ nuclear spins, manifested as a strong parity preference for the rotational states of the products. We leverage this effect to alter the occupation of these product states by changing the coherent superposition of initial nuclear spin states with an external magnetic field. In this way, we are able to control both the inputs and outputs of a reaction with quantum-state resolution. The techniques demonstrated here open up the possibilities to study quantum entanglement between reaction products and ultracold reaction dynamics at the state-to-state level.

International audience; Kesterite quaternary material Cu2ZnSnS4, (CZTS)-based thin-film solar cells have attracted intensive attention owing to their earth-abundant nature, stable thermodynamic structure, and large potential for high power conversion efficiency (PCE) defined by their suitable optoelectronic properties. As a widely used thin film preparation method, pulsed laser deposition (PLD) has not been fully studied in CZTS thin-film solar cell. Herein, a promising route based on PLD from a quaternary target and post-sulphuration for CZTS thin film was achieved. Through systematical investigation and optimization of substrate temperature, laser pulse energy, and sulfurization temperature, the CZTS thin films showed single kesterite structure, high (112) orientation, and dense polycrystalline grains with controlled composition. The CZTS thin-film solar cell exhibited a record PCE of 6.62%, the highest reported value when using pulsed laser deposited and sulfurized process, due to its lower series resistance, reduced grain boundary effects, superior interface quality, and a suitable depletion width. This research offers a facile and robust preparation method for CZTS films with enhanced photovoltaic properties and increased efficiency.

The status of FOXP3 and its isoforms in hepatocellular carcinoma (HCC) is unclear. We aimed to investigate the expression and function of FOXP3 and its isoforms in HCC. The study was performed on 84 HCC patients, HCC cell lines and a mouse tumor model. The levels of FOXP3 and its isoforms were determined by nested PCR, quantitative real-time PCR and immunohistochemistry (IHC) staining. The correlation between their levels and clinicopathologic characteristics was analyzed. The full length of FOXP3 (FOXP3) and exon 3-deleted FOXP3 (FOXP3Δ3) were found to be the major isoforms in HCC. The levels of FOXP3Δ3 mRNA and protein in HCC tumor samples were not significantly different from their adjacent normal tissues. The high expression of FOXP3 protein in HCC patients showed a good overall survival. The overexpression of FOXP3 significantly reduced tumor cell proliferation, migration and invasion. The immunofluorescence result indicated that FOXP3 needed to be translocated into the nucleus to exert its inhibitory function. The luciferase assay demonstrated that FOXP3 could be synergistic with Smad2/3/4 to inhibit the oncogene c-Myc. The co-immunoprecipitation results further revealed that FOXP3 could interact with Smad2/3/4. The chromatin immunoprecipitation (ChIP) assay showed that both FOXP3 and Smad2/3/4 bound the promoter of the c-Myc to inhibit it. The in vivo mouse tumor model study confirmed the inhibitory effect of FOXP3. Collectively, the expression of tumor FOXP3 can inhibit the growth of HCC via suppressing c-Myc directly or indirectly via interacting with Smad2/3/4. Therefore, FOXP3 is a tumor suppressor in HCC.

Previous studies have implicated an essential role for UHRF1-mediated histone H3 ubiquitination in recruiting DNMT1 to replication sites for DNA maintenance methylation during S phase of the cell cycle. However, the regulatory mechanism on UHRF1-mediated histone ubiquitination is not clear. Here we present evidence that UHRF1 and USP7 oppositely control ubiquitination of histones H3 and H2B in S phase of the cell cycle and that DNMT1 binds both ubiquitinated H3 and H2B. USP7 knockout markedly increased the levels of ubiquitinated H3 and H2B in S phase, the association of DNMT1 with replication sites and importantly, led to a progressive increase of global DNA methylation shown with increased cell passages. Using DNMT3A/DNMT3B/USP7 triple knockout cells and various DNA methylation analyses, we demonstrated that USP7 knockout led to an overall elevation of DNA methylation levels. Mechanistic study demonstrated that USP7 suppresses DNMT1 recruitment and DNA methylation through its deubiquitinase activity and the interaction with DNMT1. Altogether our study provides evidence that USP7 is a negative regulator of global DNA methylation and that USP7 protects the genome from excessive DNA methylation by attenuating histone ubiquitination-dependent DNMT1 recruitment.

As an important member of cytochrome P450 (CYP) enzymes, CYP17A1 is a dual-function monooxygenase with a critical role in the synthesis of many human steroid hormones, making it an attractive therapeutic target. The emerging structural information about CYP17A1 and the growing number of inhibitors for these enzymes call for a systematic strategy to delineate and classify mechanisms of ligand transport through tunnels that control catalytic activity. In this work, we applied an integrated computational strategy to different CYP17A1 systems with a panel of ligands to systematically study at the atomic level the mechanism of ligand-binding and tunneling dynamics. Atomistic simulations and binding free energy computations identify the dynamics of dominant tunnels and characterize energetic properties of critical residues responsible for ligand binding. The common transporting pathways including S, 3, and 2c tunnels were identified in CYP17A1 binding systems, while the 2c tunnel is a newly formed pathway upon ligand binding. We employed and integrated several computational approaches including the analysis of functional motions and sequence conservation, atomistic modeling of dynamic residue interaction networks, and perturbation response scanning analysis to dissect ligand tunneling mechanisms. The results revealed the hinge-binding and sliding motions as main functional modes of the tunnel dynamic, and a group of mediating residues as key regulators of tunnel conformational dynamics and allosteric communications. We have also examined and quantified the mutational effects on the tunnel composition, conformational dynamics, and long-range allosteric behavior. The results of this investigation are fully consistent with the experimental data, providing novel rationale to the experiments and offering valuable insights into the relationships between the structure and function of the channel networks and a robust atomistic model of activation mechanisms and allosteric interactions in CYP enzymes.

SARS-CoV-2 has caused the largest pandemic of the twenty-first century (COVID-19), threatening the life and economy of all countries in the world. The identification of novel therapies and vaccines that can mitigate or control this global health threat is among the most important challenges facing biomedical sciences. To construct a long-term strategy to fight both SARS-CoV-2 and other possible future threats from coronaviruses, it is critical to understand the molecular mechanisms underlying the virus action. The viral entry and associated infectivity stems from the formation of the SARS-CoV-2 spike protein complex with angiotensin-converting enzyme 2 (ACE2). The detection of putative allosteric sites on the viral spike protein molecule can be used to elucidate the molecular pathways that can be targeted with allosteric drugs to weaken the spike-ACE2 interaction and, thus, reduce viral infectivity. In this study, we present the results of the application of different computational methods aimed at detecting allosteric sites on the SARS-CoV-2 spike protein. The adopted tools consisted of the protein contact networks (PCNs), SEPAS (Affinity by Flexibility), and perturbation response scanning (PRS) based on elastic network modes. All of these methods were applied to the ACE2 complex with both the SARS-CoV2 and SARS-CoV spike proteins. All of the adopted analyses converged toward a specific region (allosteric modulation region [AMR]), present in both complexes and predicted to act as an allosteric site modulating the binding of the spike protein with ACE2. Preliminary results on hepcidin (a molecule with strong structural and sequence with AMR) indicated an inhibitory effect on the binding affinity of the spike protein toward the ACE2 protein.

Background Dehydrocorydaline (DHC) and canadine (THB) are two active alkaloid compounds in Corydalis yanhusuo (Y.H. Chou & Chun C. Hsu) W.T. Wang ex Z.Y. Su & C.Y. Wu (Papaveraceae) (Rhizoma Corydalis). DHC and THC were previously shown to exert anti-platelet aggregation effect dose-dependently, but their exact mechanisms had not yet been addressed. Therefore, it is essential to study the mechanisms of DHC and THB affecting on platelet's function. Purpose To investigate the anti-platelet effects and corresponding signal cascades of DHC and THB on platelet aggregation. Methods Firstly, in vitro anti-platelet aggregation of DHC and THB induced by different agonists including thrombin (THR), adenosine diphosphate (ADP) and arachidonic acid (AA) were determined through turbidimetry method. Then the possible target-related platelet proteins after treated with DHC/THB were separated and identified by two dimensional gel electrophoresis (2-DE) and MALDI-TOF-MS/MS analysis, respectively. Finally, the signal cascades network induced by DHC/THB were predicted through functional analysis of these proteins along with the determination of platelet DAG concentration. Results The platelet aggregation stimulated by THR, ADP and AA were inhibited by DHC and THB dose-dependently to a certain degree. Meanwhile, DHC and THB had the strongest effect on ADP- and THR-induced platelet aggregation respectively. In addition, treatment of these two compounds caused regulations of about sixty proteins in platelet, including cytoskeleton proteins, cell signaling proteins, proteins related to material energy metabolism, etc. Conclusions Using proteomic analysis combined with platelet aggregation test and ELISA, this study was successful in exploring the possible mechanisms of DHC/THB on platelet aggregation. DHC might inhibit platelet aggregation by a mechanism involving the ADP receptors P2Y1 and P2Y12, and the effect of THB on platelet function may be related to its binding to THR receptor PAR1 for mediated Gi signaling pathway. These results provide fundamental information for the anti-thrombotic effect of RC.

Stereolithography (SLA) is a form of 3D printing technology used for the production parts and patterns in a layer by layer fashion. Traditionally, 3D printing has been used for the manufacture of prototypes, however it is increasingly being used for the production of parts in small volumes. However, there are limited materials that can be used to produce parts using this process and they commonly need additional processes to produce a finished part. Additionally, 3D printing is time-consuming and is currently not suitable for the large scale production of low-cost parts. Injection moulding, on the other hand, is a process where molten polymer is forced into a cooled metal mould, which solidifies the polymer into the shape of the mould. However, set up costs for injection moulding are prohibitively high for short production or pilot runs due to the cost of the metal mould. Hence, there is a lot of interest in a hybrid system which uses 3D printing to produce the tools for use in Injection moulding. However, recent work in AIT has shown that the 3D printed inserts are prone to wear and breakdown due to the high pressures and temperatures involved in injection moulding. As such, the current study aims to develop reinforced thermally conductive polymer resins for use in 3D printing of tooling. Initial trials include the incorporation of a range of nanofillers including silver, copper, halloysite and other nanoclays. These fillers were added to a photopolymer resin, cured and characterised in terms of thermal conductivity, mechanical properties, contact angle, hardness and scanning electron microscopy. Initial results indicate that the incorporation of conductive copper and silver nanoparticles does not have a significant effect on thermal conductivity. Conversely, the incorporation of Halloysite nanoclay loading at 3 wt% significantly increased the thermal conductivity of the resin to 0.721 w/mk from 0.681 w/mk for the cured neat resin. These results indicate that nanofiller can be used to increase the thermal conductivity of commercially available SLA resins. However further work is needed before these materials are a viable alternative to metal tooling in injection moulding applications.

Improving the cementitious activity and volume stability of steel slag by thermal reconstruction is an innovative method for efficient utilization of steel slag. In this study, different amounts of CaF2 and CaSO4 were added to steel slag as a mineralizer based on the determining admixtures needed for the reconstruction reaction, and the effects of CaF2 and CaSO4 on the cementitious activity and volume stability of the reconstructed steel slag were investigated. The results show that when the CaF2 content is increased to 5 wt%, the cementitious activity index of the reconstructed steel slag gradually increases to 92%, which is 12% higher than the first level technical requirement specified by the national standards, and the free CaO (f - CaO) and MgO (f-MgO) contents gradually decrease to 0.35 and 0.13 wt%, respectively. With increasing CaSO4 content, the cementitious activity index first increases and then decreases, while the contents of f -CaO and f-MgO show the opposite trend. When the CaSO4 content is 2 wt%, the activity index is 105%,which is 25%higher than the first level technical requirement specified by the national standards, and the f -CaO and f-MgO contents reach minima of 0.44 and 0.35 wt%, respectively.

The Mesozoic (especially the Cretaceous) sequences in the northern South China Sea (SCS) are important potential targets of oil and gas exploration; however, they are currently poorly understood. We use organic petrology and geochemistry to evaluate the hydrocarbon potential and study depositional environment of the Cretaceous black mudstones and shales from the Dayawan Section in the Guangdong Province, China. These mudstones and shales yield total organic carbon (TOC) contents of 0.63%–2.76% and most samples meet the requirement for higher TOC source rocks. Organic matters in the mudstones and shales were sourced mainly from higher plants as well as subordinate benthic macroalgae. Organic petrology and geochemical data suggested that the organic matters were dominated by Type-III and minor Type-II, and generally have low thermal maturity. Thus, we evaluated the black mudstones and shales have a potential for hydrocarbon generation (especially gas prone). Pr/Ph, trace elements, and mixture source of organic matter suggested that these black mudstones and shales formed in a coastal–lacustrine environment, characterized by weakly oxidizing−weakly reducing conditions and low-salinity. A marine transgression developing in the middle part of the section was recognized. Generally, the northern SCS, which exhibits the more marine influence, likely contains source rocks with higher TOC contents and better organic matter types. The Cretaceous source rocks with higher liquid hydrocarbon generation potential may occur locally in the Pearl River Mouth Basin.