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SMC2 (structural maintenance of chromosomes 2) is the core subunit of condensins, which play a central role in chromosome organization and segregation. However, the functions of SMC2 in embryonic development remain poorly understood, due to the embryonic lethality of homozygous SMC2−/− mice. Herein, we explored the roles of SMC2 in the liver development of zebrafish. The depletion of SMC2, with the CRISPR/Cas9-dependent gene knockout approach, led to a small liver phenotype. The specification of hepatoblasts was unaffected. Mechanistically, extensive apoptosis occurred in the liver of SMC2 mutants, which was mainly associated with the activation of the p53-dependent apoptotic pathway. Moreover, an aberrant activation of a series of apoptotic pathways in SMC2 mutants was involved in the defective chromosome segregation and subsequent DNA damage. Therefore, our findings demonstrate that SMC2 is necessary for zebrafish liver development.

SMC2 (structural maintenance of chromosomes 2) is the core subunit of condensins, which play a central role in chromosome organization and segregation. However, the functions of SMC2 in embryonic development remain poorly understood, due to the embryonic lethality of homozygous SMC2−/− mice. Herein, we explored the roles of SMC2 in the liver development of zebrafish. The depletion of SMC2, with the CRISPR/Cas9-dependent gene knockout approach, led to a small liver phenotype. The specification of hepatoblasts was unaffected. Mechanistically, extensive apoptosis occurred in the liver of SMC2 mutants, which was mainly associated with the activation of the p53-dependent apoptotic pathway. Moreover, an aberrant activation of a series of apoptotic pathways in SMC2 mutants was involved in the defective chromosome segregation and subsequent DNA damage. Therefore, our findings demonstrate that SMC2 is necessary for zebrafish liver development.

Developing metal-free catalysts with high catalytic activity for oxygen evolution reaction (OER) is essentially important for energy and environment-related techniques. Compared with individual element doping, doping carbon materials with multiple heteroelements has more advantages for enhancing the OER performance. However, doped sites for the different atoms are highly uncontrollable under the reported methods, which hinder the deeper understanding on the relationship between structure and property, and also limit the enhancement of catalytic activity. Our latest research has reported a method to site-controlled introducing a new form of nitrogen atoms, i.e. sp-hybridized nitrogen (sp-N), into graphdiyne, showing its potential advantages in OER catalysis. Since the sites of sp-N atoms are defined in graphdiyne, and the doping sites for S atoms are well understood, the relative position between N and S can be further defined. It gives us a chance to understand deeply the mechanism in the N, S heteroelements doped metal-free catalyst. Experimental results present that the codoping of sp-N and S atoms brought an excellent OER performance with low overpotential and high current density owning to the effectively synergistic effect of the stereodefined heteroatoms. This work was supported by the National Key Research and Development Program of China (2016YFB0600903) and the National Natural Science Foundation of China (21590795, 21820102002), the Scientific Instrument Developing Project of the Chinese Academy of Sciences (Grant No. YZ201623), Queensland-Chinese Academy of Sciences Collaborative Science Fund (122111KYSB20170001), and Chinese Academy of Sciences (CAS) Interdisciplinary Innovation Team.

The dehydration products of gypsum under different temperature and water vapor pressure were investigated by thermodynamic theory. Additionally, the rehydration mechanism of soluble anhydrite was also studied by Monte Carlo (MC) simulations. The thermodynamic calculation results reveal that the dehydration mechanism of gypsum significantly depended on ambient temperature and water vapor pressure. In the high-temperature and low water vapor pressure region, gypsum dehydrates to form γ-CaSO4 in a single-step process (CaSO4·2H2O → γ-CaSO4); with increasing water vapor pressure, gypsum undergoes the CaSO4·2H2O → γ-CaSO4 → β-CaSO4·0.5H2O reaction path and as water vapor pressure increases further, the occurrence of a two-step conversion path CaSO4·2H2O → β-CaSO4·0.5H2O → γ-CaSO4 was observed. It was also found that gypsum is stable in the low-temperature and high water vapor pressure region and does not dehydrate to form any calcium sulfate hemihydrate. Finally, the rehydration mechanism of soluble anhydrite was studied by MC simulations. The simulation results are in agreement with the experimental data and support the finding that γ-CaSO4 rehydration forms CaSO4·0.67H2O in high relative humidity. Another important result revealed by the MC simulation is that γ-CaSO4 has an extraordinary ability to capture water molecules from an extremely dry atmosphere, which is very useful in some fields, such as in drying processes and even for extracting liquid water from extremely dry atmosphere.

Most currently available bioreactors have some defects in the expression, activity, or purification of target protein and peptide molecules, whereas the mucus gland of fish can overcome these defects to become a novel bioreactor for the biopharmaceutical industry. In this study, we have evaluated the practicability of developing a mucus gland bioreactor in loach (Paramisgurnus dabryanus). A transgenic construct pT2-krt8-IFN1 was obtained by subcloning the promoter of zebrafish keratin 8 gene and the type I interferon (IFN1) cDNA of grass carp into the SB transposon. The IFN1 expressed in CIK cells exhibited an antiviral activity against the replication of GCRV873 and activated two genes downstream of JAK-STAT signaling pathway. A transgenic loach line was then generated by microinjection of the pT2-krt8-IFN1 plasmids and in vitro synthesized capped SB11 mRNA. Southern blots indicated that a single copy of IFN1 gene was stably integrated into the genome of transgenic loach. The expression of grass carp IFN1 in transgenic loaches was detected with RT-PCR and Western blots. About 0.0825 &micro, g of grass carp IFN1 was detected in 20 &micro, L mucus from transgenic loaches. At a viral titer of 1 &times, 103 PFU/mL, plaque numbers on plates containing mucus from transgenic loaches reduced by 18% in comparison with those of the control, indicating that mucus of IFN1-transgenic loaches exhibited an antiviral activity. Thus, we have successfully created a mucus gland bioreactor that has great potential for the production of various proteins and peptides.

The amount of waste clay bricks has been increasing as the demolition of old buildings in China, which has caused the serious environmental problem. Utilizing waste clay bricks as lightweight aggregates for preparing concrete is a new idea to consume them and save natural resources. Based on this concept, an experimental study was carried out to evaluate the feasibility of preparing lightweight aggregate concrete with waste clay bricks by testing the properties of prepared lightweight aggregate concrete. The results indicate that the dry densities of all mixtures are about 1700 kg/m3∼1850 kg/m3, meeting the standard requirement for lightweight aggregate concrete (≤1950 kg/m3), the 28-day compressive strength could reach up to 40 MPa, and corresponding static elasticity modulus is about 26 GPa. Moreover, both freeze-thaw resistance and carbonation resistance of all mixtures could satisfy the service requirements of Chinese standard (JGJ 51), and the chloride migration coefficient varies from 5.0 × 10−12 m2/s and 19.0 × 10−12 m2/s, corresponding with chloride penetration resistance of concrete from high to low. It has been proved that consuming waste clay bricks by preparing lightweight aggregate concrete with waste clay bricks as coarse and fine aggregates is a promising way and has application potentials.

As a new member of the carbon allotrope family, graphdiynes (GDs) consist of both sp- and sp(2)-hybridized carbon atoms, possessing unique pi-conjugated carbon skeletons and expanded 18C-hexagonal pores in two dimensions. In contrast with the zero band gap graphene (GR), GD is a semiconductor with a direct band gap of 1.22 eV calculated according to the density functional theory (DFT) using the HSE06 method; this makes it a potential semiconductor material that can supplant silicon in the integrated circuit industry. Moreover, owing to the presence of diacetylenic linkages between its hexagonal carbon rings, GD shows electron-deficient properties, which lead to its electron-accepting tendency. Graphdiynes exhibit unusual semiconducting properties with excellent charge mobilities and electron transport properties that are associated with its distinct topological and electronic structures. Graphdiynes play the role of not only electron-acceptors that efficiently collect the electrons from other materials but also electron-donors that inject electrons into other systems, thus exhibiting excellent electron-transfer enhancement characteristics. The unique electron-transfer enhancement property of GDs inspired us to summarize the interactions between GDs and other materials including metal oxides, metal nano-particles, and organic molecules. In this review paper, we first introduce the TiO2/GD nanocomposite, because the linking of GDs and titania nanoparticles (P25) through the Ti-O-C bond sets an important precedent for exploring the electron-transfer behaviors involving GDs and the metal oxide. These results indicate that the GDs can act as acceptors of the photogenerated electrons in the TiO2/GD system, effectively suppressing charge recombination and resulting in excellent photocatalytic properties. Nevertheless, the GDs in CdSe quantum dots (QDs)/GD composites are able to collect photogenerated holes from the QDs and perform as promising hole-transfer materials in the photoelectrochemical cell for water splitting. As a result, the interactions between GDs and various metal compounds should be explored to deeply understand the electron-transfer properties of GDs. Furthermore, GDs can be also used as electron donors to reduce PdCl42- to Pd nanoparticles that can subsequently be used for the electroless deposition of highly dispersed Pd nanoparticles. Based on electrostatic potential surface analysis over the Pt-2/GD, GDs can attract the electron cloud from the Pt nanoparticles and produce a positive polarization of the metal atom surface. However, due to its large pi-conjugated system, GD can also collect and transfer electrons from the electrode under a bias voltage, making it a new type of electrocatalyst material, especially for single-atom catalysts. The interactions between GDs and metal particles/clusters/atoms have attracted the broad attention of the rapidly developing field of single-atom catalysis. Finally, research on the interactions between GDs and organic molecules, especially biomolecules, is still in its infancy and requires development. In summary, we overview the recent research progress on GD and its enhanced ability for electron transfer in this review paper, including metal oxides/GD, metal nano-particles/GD, polymers/GD, and organic molecules/GD, from both experimental and theoretical perspectives, and emphasize the interactions and electron-transfer enhancement properties.

The manufacture of cement is considered as a high energy consumption and environmental pollution process, and it is necessary to figure out a way to reduce the consumption of cement in construction industry. The waste clay brick is a kind of construction waste with pozzolanic activity, which could be used to prepare blended cement after grinding. However, the particle size of clay brick powder (CBP) will influence its pozzolanic activity and properties of blended cement, which needs to be clarified. Therefore, in this study, the pozzolanic activity of CBP and properties of blended cement containing CBP were investigated. The results show that with the increase of grinding time, the CBP particles tend to be refined and spherical, which will increase the specific surface area and pozzolanic activity of CBP. The decrease of CBP particle size in blended cement paste can accelerate the early-age hydration and decrease the setting time since the ultrafine CBP could become the crystallization nucleus. The compressive strength of mortars with 30% CBP is 10%–35% lower than that without CBP, and the smaller the CBP particle size, the faster the compressive strength grows. Moreover, the hydration products and pore structure results also prove that the CBP with smaller particle size will consume more calcium hydroxide to react, which could make the microstructure denser and obtain stronger compressive strength growth at later ages. Meanwhile, the environmental impact and cost calculations indicate that the energy intensity and CO2 emissions of blended cement are obviously lower than Portland cement. It could be concluded that the pozzolanic activity of CBP will be enhanced with the decrease of particle size, and this research provided the reference for application of waste clay brick to produce green construction materials.

Graphdiyne can serve as both the electron‐acceptor and electron‐donor due to its distinct topological and electronic structure. The unique electron‐transfer behavior promotes its widespread applications. In article number 1800959, Dan Wang and co‐workers discuss advances in how graphdiyne and its composite materials are used for photo‐ and electrochemical energy conversion areas, such as solar cells, photocatalysis, water splitting, and fuel cells.

As a rising star of carbon allotropes, graphynes (GYs) merely consist of sp‐ and sp2‐hybridized carbon atoms, which endow them a large conjugated network and expanded 2D porous structure. With unique topological structure, GYs display unusual semiconducting properties, especially in the aspects of charge mobility and electron transport. Among the members of the GY family, only graphdiyne (GD) can be successfully synthesized in large quantities. The advanced properties of GD make it promising in various applications. Here, the recent progress in the synthesis of GD and GD‐based composites is reviewed as well as their applications in photorelated and electrocatalytic applications. It is hoped that this Review will promote the development and applications of carbon chemistry.