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Quorum sensing (QS) offers cell density dependent dynamic regulations in cell culture through devices such as synchronized lysis circuit (SLC) and metabolic toggle switch (MTS). However, there is still a lack of studies on cocultivation with a combination of different QS-based devices. Taking the production of isopropanol and salidroside as case studies, we have mathematically modeled a comprehensive set of QS-regulated cocultivation schemes and constructed experimental combinations of QS devices, respectively, to evaluate their feasibility and optimality for regulating growth competition and corporative production. Glucose split ratio is proposed for the analysis of competition between cell growth and targeted production. Results show that the combination of different QS devices across multiple members offers a new tool with the potential to effectively coordinate synthetic microbial consortia for achieving high product titer in cross-feeding cocultivation. It is also evident that the performance of such systems is significantly affected by dynamic characteristics of chosen QS devices, carbon source control and the operational settings. This study offers insights for future applications of combinational QS devices in synthetic microbial consortia.

β‐thalassaemia is a prevalent hereditary haematological disease caused by mutations in the human haemoglobin β (HBB) gene. Among them, the HBB IVS2‐654 (C > T) mutation, which is in the intron, creates an aberrant splicing site. Bone marrow transplantation for curing β‐thalassaemia is limited due to the lack of matched donors. The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR‐associated protein 9 (Cas9), as a widely used tool for gene editing, is able to target specific sequence and create double‐strand break (DSB), which can be combined with the single‐stranded oligodeoxynucleotide (ssODN) to correct mutations. In this study, according to two different strategies, the HBB IVS2‐654 mutation was seamlessly corrected in iPSCs by CRISPR/Cas9 system and ssODN. To reduce the occurrence of secondary cleavage, a more efficient strategy was adopted. The corrected iPSCs kept pluripotency and genome stability. Moreover, they could differentiate normally. Through CRISPR/Cas9 system and ssODN, our study provides improved strategies for gene correction of β‐Thalassaemia, and the expression of the HBB gene can be restored, which can be used for gene therapy in the future.

A high-strength Mg-10Gd-3Y-1Zn-0.4Zr (GWZ1031K, wt.%) alloy was prepared by laser powder bed fusion (LPBF), and the microstructure and mechanical properties of the as built, LPBF-T5, LPBF-T4, and LPBF-T6 states were systematically studied. The as built alloy is composed of fine equiaxed ɑ-Mg grains with an average grain size of 4.1 ± 0.5 μm, reticular β-(Mg,Zn)3(Gd,Y) eutectic phase and flaky Y2O3 oxide phase, and exhibits yield strength (YS) of 310 ± 8 MPa, ultimate tensile strength (UTS) of 347 ± 6 MPa and elongation (EL) of 4.1 ± 0.8%. A simple direct aging heat treatment at 175℃ for 64 h after LPBF leads to an ultra-high YS of 365 ± 12 MPa but a low EL of 0.8 ± 0.3% in the LPBF-T5 alloy. The solution heat treatment improves ductility by transforming the hard and brittle eutectic phase into the relatively soft and deformable lamellar long period stacking ordered (LPSO) structure inside grains and X phase at grain boundaries without obvious grain growth. Moreover, the LPBF-T4 alloy solution-treated at 450℃ for 12 h exhibits YS of 255 ± 8 MPa, UTS of 328 ± 9 MPa, and EL of 10.3 ± 0.5%. Aging heat treatment after solution introduces numerous prismatic β′ and β1 precipitates, which help to increase tensile strength. The YS, UTS, and EL of the LPBF-T6 alloy are 316 ± 5 MPa, 400 ± 7 MPa, and 2.2 ± 0.3%, respectively. It can be concluded that the LPBF process when combined with specially designed post-processing holds great promise for the manufacturing of high-performance components of the Mg-rare earth alloys with significantly higher YS for various applications.

Mineral carbonation using alkaline industrial solid wastes is a promising CO2 sequestration technology. In this work, the effects of temperature, CO2 content, steam content, and reaction time on CO2 sequestration at atmospheric pressure were studied by the direct gas–solid carbonation of circulating fluid bed fly ash in a thermogravimetric analyzer and a fixed bed reactor system. Results indicate that increasing the temperature and the content of CO2 and H2O(g) can improve the CO2 sequestration efficiency of the circulating fluid bed fly ash. However, the effect of CO2 content is not as significant as that of temperature and H2O(g). The maximum CO2 sequestration capacity of 60 g CO2/kg fly ash with a maximum sequestration efficiency of 28.74% was achieved at 600 °C with 20% H2O(g) addition. The Brunauer–Emmett–Teller surface area and the pore volume decreased with the increase in average pore size after carbonation, due to the formation of a dense carbonate protective layer and pore blockage. With steam addition, the surface area and the pore volume increase, which contributes to the conversion of CaO to CaCO3. The production of Ca(OH)2 or transient Ca(OH)2 and the enhancement of CO2 molecular mobility account for the promotion of steam in the carbonation process. The promotion mechanism of steam in different stages of reaction and temperature were explored in detail. Given the rich reserves of fly ash in China, it shows a good application prospect to use the Chinese fly ash as a mineral carbonation feedstock, which may not only reduces CO2 emission, but also stabilizes the wastes.

Plasma nitriding was conducted as post-treatment for surface texture on pure titanium to obtain a continuous nitriding layer. Supersonic fine particles bombarding (SFPB) was carried out to prepare surface texture. The surface morphologies and chemical composition were analyzed using scanning electron microscope and energy disperse spectroscopy. The microstructures of modified layers were characterized by transmission electron microscope. The tribological properties of surface-textured and duplex-treated pure titanium under oil lubrication condition were systematically investigated in the ball-on-plate reciprocating mode. The effects of applied load and sliding velocity on the tribological behavior were analyzed. The results show that after duplex treatments, the grains size in modified layer becomes slightly larger, and hardness is obviously improved. Wear resistance of duplex-treated pure titanium is significantly improved referenced to untreated and surface-textured pure titanium, which is 3.22 times as much as untreated pure titanium and 2.15 times of that for surface-textured pure titanium, respectively.

Human MSX1 gene is mapped to chromosome 4 and encodes a 303aa homeobox protein MSX1. MSX1 expression appears during early tooth development of vertebrate embryogenesis. Mutations in this protein are related to human tooth anomalie, cleft lip and palate and congenital ectodermal dysplasia syndrome. Most of the confirmed pathogenic mutations are located in exon2 encoded homeobox domain. Here, we report the establishment of MSX1 gene knockout human embryonic stem (hES) cell lines by CRISPR-Cas9 technology. These cell lines provide good materials for further studies of the roles MSX1 plays in human tooth development and congenital tooth agenesis.

47, XXX syndrome is one of several sex-chromosomal aneuploidies, and it has an incidence of approximately 1/1000 in newborn females. Because of heterogeneity in X-inactivation, these patients may exhibit a variety of clinical symptoms. Here, we report the generation of an integration-free human induced pluripotent stem cell line (GZHMUi001-A) by using Sendai virus to reprogram peripheral blood mononuclear cells from a 47, XXX syndrome patient with premature ovarian failure. This 47, XXX iPS cell line has characteristics of pluripotent stem cells and is a useful tool for the investigation of this X chromosome aneuploid disease.

Yak (Bos grunniens) is an animal mainly living on the Tibetan Plateau. Yak skin is a valuable resource that is wasted in the meat production process. This study aimed to prepare yak skin gelatin hydrolysates (YSGH) from yak skin through enzymatic hydrolysis and investigate functional characterization of YSGH. We showed that trypsin was more effective than neutrase, papain, and pepsin in increasing the degree of hydrolysis (DH) of YSGH. The conditions of enzymatic hydrolysis were optimized using central composite design (CCD) and response surface method (RSM), and the highest DH value of 31.96% was obtained. We then analyzed the amino acid compositions and molecular weight distribution of peptides in YSGH. The obtained YSGH exhibited certain antioxidant activity and excellent ACE-inhibitory activity (IC50 = 0.991 mg/mL). In addition, the solubility (98.79%), emulsification, and foaming properties of YSGH developed here were also evaluated. With these physicochemical and biological functions, YSGH had potential applications in food, pharmaceuticals, and cosmetics as an ingredient.

This paper investigated the effects of Gd and Y solutes on aging behaviour and corresponding mechanical properties of the extruded Mg–Gd(-Y)-Zn-Mn alloys at room and elevated temperatures. The results show that aging treatment provided significant improvement of ~100 MPa in strength by forming ellipsoidal β ′ nanophases in the as-extruded alloys. Partially substituting Y for Gd in the as-extruded Mg-Gd-Zn-Mn alloys can delay age-hardening response, but improve the strength increment after aging treatment. As the Y/Gd atomic ratio changed from 0 to 1, the Mg-1.75Gd-0.75Y-0.5Zn–Mn(at.%) alloy with a Y/Gd atomic ratio of 0.4 obtained the higher peak-hardness and mechanical properties. Enhanced age-hardening response and better mechanical properties were detected after separate additions of Y and Gd. The extruded-T5 Mg-2.5Gd-0.75Y-0.5Zn-0.3Mn alloy exhibited superior ultimate tensile strengths of 520 MPa at room temperature, 344 MPa at 250 °C, and 225 MPa at 300 °C. Fracture behaviours reveal that a change in predominant deformation mechanism from one based on dislocations to one mediated by grain boundary (GB) processes was found as the tensile temperatures arise from 250 °C to 300 °C. The activation of GB sliding of the fine grains partially resulted in the decrease of tensile strength at 300 °C.

The semisolid billets of Mg-10Gd-3Y-1Zn-0.4Zr (wt%) alloy were prepared by the strain-induced melt activation (SIMA) route, and the effects of isothermal heating parameters on the morphology and coarsening kinetics of primary solid grains were studied. It was found that the average grain size increased with the increase of isothermal time while the grain size showed different changing laws with the temperature at different isothermal times. The growth behavior of the primary solid grains was predominantly governed by the Ostwald ripening mechanism, although there is coalescence mechanism in some cases. As the isothermal temperature increased from 550 °C to 590 °C, the coarsening rate constant increased continuously and then declined when the temperature was further increased to 610 °C. Compared with other SIMA processed magnesium alloys, the present alloy showed a significantly lower grain coarsening rate constant due to the inhibiting effect of rare earth (RE) elements on coarsening. This research has provided an insight into the microstructural evolution of Mg-RE alloy under different heating conditions, and will provide valuable information for potential industrial applications.

Hemophilia A (HA), is a X-linked recessive congenital bleeding disorder, caused by deficiency of the coagulation factor VIII (FVIII) which is encoded by coagulation factor 8 (F8). HA affects 1 of every 5,000 males worldwide. The intron 22 inversion (Inv22) mutation of F8 causes about 45% of severe HA cases. Here, we generated induced pluripotent stem cells (iPSCs) from a HA patient with Inv22 mutation by electroporation of urine-derived cells (UCs) with episomal plasmids under feeder-free, virus-free, serum-free condition and without oncogene c-MYC. This iPSCs line could facilitate future applications of human iPSCs by provide a valuable cell model.

A Mg-11.00Gd-1.77Zn-0.43Zr (wt.%) alloy named GZ112K was prepared by selective laser melting (SLM) with different processing parameters. The formability, element vaporization, microstructure and tensile properties of the SLMed samples at different scanning speed and hatch spacing were characterized. The process map at a constant laser power of 80 W for the alloy has been established. It shows that the optimum scanning speed and hatch spacing are 300–700 mm/s and 100 μm respectively. The SLMed samples have fine grains of about 2 μm and dispersed eutectic phase of β-(Mg,Zn)3Gd due to the very high cooling rate, high solid solubility of Gd and Zn elements in ɑ-Mg matrix owing to the effect of solute trapping. The SLMed GZ112K alloy with scanning speed of 300 mm/s and hatch spacing of 100 μm has yield strength (YS) of 325 MPa, ultimate tensile strength (UTS) of 332 MPa and elongation of 4.0% at room temperature. Compared with as-cast alloy, the SLMed GZ112K alloy has much higher YS (+162 MPa), UTS (+122 MPa) and comparable elongation (+0.4%).

EDA is a gene located at Xq13.1. It encodes different isoforms of tumor necrosis factor (TNF) superfamily member ectodysplasin A. Ectodysplasin A is a transmembrane protein which can be cleaved to form a secreted form and interact with EDA receptor to mediate the development of ectoderm. Mutations of the EDA gene are related to ectodermal dysplasia and tooth agenesis. Here, we report the establishment of the EDA gene knockout human embryonic stem (hES) cell line by CRISPR-Cas9 technology. This cell line provides good materials for further studies of the roles ectodysplasin A plays in ectoderm differentiation and tooth development.

MicroRNAs (miRNAs) are emerging critical regulators of cell function that frequently reside in clusters throughout the genome. They influence a myriad of cell functions, including the generation of induced pluripotent stem cells, also termed reprogramming. Here, we have successfully delivered entire miRNA clusters into reprogramming fibroblasts using retroviral vectors. This strategy avoids caveats associated with transient transfection of chemically synthesized miRNA mimics. Overexpression of 2 miRNA clusters, 106a-363 and in particular 302-367, allowed potent increases in induced pluripotent stem cell generation efficiency in mouse fibroblasts using 3 exogenous factors (Sox2, Klf4, and Oct4). Pathway analysis highlighted potential relevant effectors, including mesenchymal-to-epithelial transition, cell cycle, and epigenetic regulators. Further study showed that miRNA cluster 302-367 targeted TGFβ receptor 2, promoted increased E-cadherin expression, and accelerated mesenchymal-to-epithelial changes necessary for colony formation. Our work thus provides an interesting alternative for improving reprogramming using miRNAs and adds new evidence for the emerging relationship between pluripotency and the epithelial phenotype.

β-Thalassemia (β-Thal) is a group of life-threatening blood disorders caused by either point mutations or deletions of nucleotides in β-globin gene (HBB). It is estimated that 4.5% of the population in the world carry β-Thal mutants (1), posing a persistent threat to public health. The generation of patient-specific induced pluripotent stem cells (iPSCs) and subsequent correction of the disease-causing mutations offer an ideal therapeutic solution to this problem. However, homologous recombination-based gene correction in human iPSCs remains largely inefficient. Here, we describe a robust process combining efficient generation of integration-free β-Thal iPSCs from the cells of patients and transcription activator-like effector nuclease (TALEN)-based universal correction of HBB mutations in situ. We generated integration-free and gene-corrected iPSC lines from two patients carrying different types of homozygous mutations and showed that these iPSCs are pluripotent and have normal karyotype. We showed that the correction process did not generate TALEN-induced off targeting mutations by sequencing. More importantly, the gene-corrected β-Thal iPS cell lines from each patient can be induced to differentiate into hematopoietic progenitor cells and then further to erythroblasts expressing normal β-globin. Our studies provide an efficient and universal strategy to correct different types of β-globin mutations in β-Thal iPSCs for disease modeling and applications.

Induced pluripotent stem cell (iPS cell) holds great potential for applications in regenerative medicine, drug discovery, and disease modeling. We describe here a practical method to generate human iPS cells from urine-derived cells (UCs) under feeder-free, virus-free, serum-free condition and without oncogene c-MYC. We showed that this approach could be applied in a large population with different genetic backgrounds. UCs are easily accessible and exhibit high reprogramming efficiency, offering advantages over other cell types used for the purpose of iPS generation. Using the approach described in this study, we have generated 93 iPS cell lines from 20 donors with diverse genetic backgrounds. The non-viral iPS cell bank with these cell lines provides a valuable resource for iPS cells research, facilitating future applications of human iPS cells.