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Abstract Background Pig organ xenotransplantation is a potential solution for the severe organ shortage in clinic, while immunogenic genes need to be eliminated to improve the immune compatibility between humans and pigs. Current knockout strategies are mainly aimed at the genes causing hyperacute immune rejection (HAR) that occurs in the first few hours while adaptive immune reactions orchestrated by CD4 T cell thereafter also cause graft failure, in which process the MHC II molecule plays critical roles. Methods Thus, we generate a 4‐gene (GGTA1, CMAH, β4GalNT2, and CIITA) knockout pig by CRISPR/Cas9 and somatic cell nuclear transfer to compromise HAR and CD4 T cell reactions simultaneously. Results We successfully obtained 4KO piglets with deficiency in all alleles of genes, and at cellular and tissue levels. Additionally, the safety of our animals after gene editing was verified by using whole‐genome sequencing and karyotyping. Piglets have survived for more than one year in the barrier, and also survived for more than 3 months in the conventional environment, suggesting that the piglets without MHC II can be raised in the barrier and then gradually mated in the conventional environment. Conclusions 4KO piglets have lower immunogenicity, are safe in genomic level, and are easier to breed than the model with both MHC I and II deletion.

Abstract Understandings of the three-dimensional social behaviors of freely moving large-size mammals are valuable for both agriculture and life science, yet challenging due to occlusions in close interactions. Although existing animal pose estimation methods captured keypoint trajectories, they ignored deformable surfaces which contained geometric information essential for social interaction prediction and for dealing with the occlusions. In this study, we develop a Multi-Animal Mesh Model Alignment (MAMMAL) system based on an articulated surface mesh model. Our self-designed MAMMAL algorithms automatically enable us to align multi-view images into our mesh model and to capture 3D surface motions of multiple animals, which display better performance upon severe occlusions compared to traditional triangulation and allow complex social analysis. By utilizing MAMMAL, we are able to quantitatively analyze the locomotion, postures, animal-scene interactions, social interactions, as well as detailed tail motions of pigs. Furthermore, experiments on mouse and Beagle dogs demonstrate the generalizability of MAMMAL across different environments and mammal species.

Abstract Background Mice with humanized livers are important models to study drug toxicology testing, development of hepatitis virus treatments, and hepatocyte transplantation therapy. However, the huge difference between mouse and human in size and anatomy limited the application of humanized mice in investigating human diseases. Therefore, it is urgent to construct humanized livers in pigs to precisely investigate hepatocyte regeneration and human hepatocyte therapy. CRISPR/Cas9 system and somatic cell cloning technology were used to generate two pig models with FAH deficiency and exhibiting severe immunodeficiency (FAH/RAG1 and FAH/RAG1/IL2RG deficiency). Human primary hepatocytes were then successfully transplanted into the FG pig model and constructed two pigs with human liver. Results The constructed FAH/RAG1/IL2RG triple-knockout pig models were characterized by chronic liver injury and severe immunodeficiency. Importantly, the FG pigs transplanted with primary human hepatocytes produced human albumin in a time dependent manner as early as 1 week after transplantation. Furthermore, the colonization of human hepatocytes was confirmed by immunochemistry staining. Conclusions We successfully generated pig models with severe immunodeficiency that could construct human liver tissues.

Fine reactive alumina powders have a significant impact on the properties of refractories at high temperatures. Except for the hydration of cement and in situ reactions, the performance of castables is also correlated with the sintering of reactive alumina. The characteristics of fine alumina powders produced by various manufacturers are quite different. This work aims to investigate the comprehensive influence of powder characteristics on the sintering behaviour of reactive alumina powders. Three types of commercial reactive alumina powders were selected for experiments. The linear shrinkage, bulk density, apparent porosity and microstructure of alumina compacts calcined at different temperatures were analysed. It was demonstrated that large specific surface area and higher SiO2 content had a positive effect on the densification of alumina compacts. The calculation based on the hypothetical composition of alumina grain boundary indicated that SiO2 mainly participated in the formation of liquid. Therefore, more liquid was generated at the grain boundary of alumina grains containing higher SiO2 content, which resulted in better sinterability of reactive alumina powders.

Background and Purpose: Burn injuries are prone to infection caused by bacteria, fungi, or other pathogens. Fungal wound infection usually has non-specific clinical symptoms.Nevertheless, in some cases, the fungal burden is so substantial that can easily be seen by the naked eyes, but this phenomenon has rarely been reported with Fusarium. Case report: A 53-year-old patient with severe burn injury was admitted to the intensive care unit of the National Hospital of Burn, Ha Noi, Vietnam. His wound was dressed with a traditional herbal product before the hospital admission. On the 5th day after the admission, some white patches suspected of fungal colonies appeared on burn lesions where the herbal medicine was placed. Histological examination (Periodic acidSchiff) and culture of biopsy samples taken from those lesions revealed fungus that was identified as Fusarium equiseti after analysis of the internal transcribed spacer and D1/D2 region of the large subunit of the 28S rDNA. The isolated strain showed susceptibility to voriconazole but resistance to fluconazole, itraconazole, caspofungin,and amphotericin B in vitro. The patient received aggressive treatment, including IV voriconazole (400 mg daily from day five); however, he could not recover. Conclusion: Fusarium should be suspected in burn patients with white patches on lesions. Antifungal susceptibility testing is important since multidrug resistance is common among Fusarium strains.

Abstract Blastocyst complementation by pluripotent stem cell (PSC) injection is believed to be the most promising method to generate xenogeneic organs. However, ethical issues prevent the study of human chimeras in the late embryonic stage of development. Primate embryonic stem cells (ESCs), which have similar pluripotency to human ESCs, are a good model for studying interspecies chimerism and organ generation. However, whether primate ESCs can be used in xenogenous grafts remains unclear. In this study, we evaluated the chimeric ability of cynomolgus monkey (Macaca fascicularis) ESCs (cmESCs) in pigs, which are excellent hosts because of their many similarities to humans. We report an optimized culture medium that enhanced the anti-apoptotic ability of cmESCs and improved the development of chimeric embryos, in which domesticated cmESCs (D-ESCs) injected into pig blastocysts differentiated into cells of all three germ layers. In addition, we obtained two neonatal interspecies chimeras, in which we observed tissue-specific D-ESC differentiation. Taken together, the results demonstrate the capability of D-ESCs to integrate and differentiate into functional cells in a porcine model, with a chimeric ratio of 0.001–0.0001 in different neonate tissues. We believe this work will facilitate future developments in xenogeneic organogenesis, bringing us one step closer to producing tissue-specific functional cells and organs in a large animal model through interspecies blastocyst complementation.

The mushy zone refers to the region of the solid-liquid system where the temperature is between the liquidus and solidus temperatures. In this zone, the turbulence of the interdendritic flow is reduced by blockage of dendrites. The mushy zone coefficient (Amush) is an important calculating parameter in the continuous casting numerical simulation process, which strongly affects the prediction of fluid flow and solidification behavior in the mold zone. However, most researchers have neglected the influence of the mushy zone coefficient, and the correct expression of this coefficient is rarely found in the literature. Generally, the lower default value of 1×105 kg·m-3·s-1 is used in the model, which leads to unrealistic results. In this study, the relationship between the mushy zone coefficient and permeability was analyzed, and the expression of the mushy zone coefficient was proposed. A coupled flow and solidification numerical model was developed to evaluate the effect of the mushy zone coefficient on the melt flow and solidification phenomena in a bloom continuous casting mold. Results show that the higher the value of the mushy zone coefficient, the stronger the damping becomes, and the faster the velocity drops as melt solidifies. A relatively high value of the mushy zone coefficient generates a "banded" form of mushy zone sandwiched between the solid and liquid phases in the mold zone. When the mushy zone coefficient is at a lower value, a wider mushy zone is obtained and the melt cools down rapidly in the mold region. In addition, the temperature at free surface is relatively low with supercooling, and the solidified shell remelts locally. The model is validated through comparison with measurements of shell thickness on a breakout shell. The value of the mushy zone coefficient ranging from 1×108 to 5×108 kg·m-3·s-1 is suggested.

To analyze the cardio-protective effects of ticagrelor in patients with acute coronary syndrome with S-T segment elevation.

Low birth efficiency and developmental abnormalities in embryos derived using round spermatid injection (ROSI) limit the clinical application of this method. Further, the underlying molecular mechanisms remain elusive and warrant further in-depth study. In this study, the embryonic day (E) 11.5 mouse fetuses and corresponding placentas derived upon using ROSI, intracytoplasmic sperm injection (ICSI), and natural in vivo fertilized (control) embryos were collected. Transcriptome and DNA methylation profiles were analyzed and compared using RNA-sequencing (RNA-seq) and whole-genome bisulfite sequencing, respectively. RNA-seq results revealed similar gene expression profiles in the ROSI, ICSI, and control fetuses and placentas. Compared with the other two groups, seven differentially expressed genes (DEGs) were identified in ROSI fetuses, and ten DEGs were identified in the corresponding placentas. However, no differences in CpG methylation were observed in fetuses and placentas from the three groups. Imprinting control region methylation and imprinted gene expression were the same between the three fetus and placenta groups. Although 49 repetitive DNA sequences (RS) were abnormally activated in ROSI fetuses, RS DNA methylation did not differ between the three groups. Interestingly, abnormal hypermethylation in promoter regions and low expression of Fggy and Rec8 were correlated with a crown-rump length less than 6 mm in one ROSI fetus. Our study demonstrates that the transcriptome and DNA methylation in ROSI-derived E11.5 mouse fetuses and placentas were comparable with those in the other two groups. However, some abnormally expressed genes in the ROSI fetus and placenta warrant further investigation to elucidate their effect on the development of ROSI-derived embryos.

Absolute pitch (AP) is a superior ability to identify or produce musical tones without a reference tone. Although a few studies have investigated the relationship between AP and high-level music processing such as tonality and syntactic processing, very little is known about whether AP is related to musical tension processing. To address this issue, 20 AP possessors and 20 matched non-AP possessors listened to major and minor melodies and rated the levels of perceived and felt musical tension using a continuous response digital interface dial. Results indicated that the major melodies were perceived and felt as less tense than the minor ones by AP and non-AP possessors. However, there was weak evidence for no differences between AP and non-AP possessors in the perception and experience of musical tension, suggesting that AP may be independent of the processing of musical tension. The implications of these findings are discussed.

Abstract Porcine‐derived xenogeneic sources for transplantation are a promising alternative strategy for providing organs for treatment of end‐stage organ failure in human patients because of the shortage of human donor organs. The recently developed blastocyst or pluripotent stem cell (PSC) complementation strategy opens a new route for regenerating allogenic organs in miniature pigs. Since the eye is a complicated organ with highly specialized constituent tissues derived from different primordial cell lineages, the development of an intact eye from allogenic cells is a challenging task. Here, combining somatic cell nuclear transfer technology (SCNT) and an anophthalmic pig model (MITFL247S/L247S), allogenic retinal pigmented epithelium cells (RPEs) were retrieved from an E60 chimeric fetus using blastocyst complementation. Furthermore, all structures were successfully regenerated in the intact eye from the injected donor blastomeres. These results clearly demonstrate that not only differentiated functional somatic cells but also a disabled organ with highly specialized constituent tissues can be generated from exogenous blastomeres when delivered to pig embryos with an empty organ niche. This system may also provide novel insights into ocular organogenesis.

Taking a 30 ton of LF as an investigated object, a gray-box model to predict the end-point temperature of molten steel in LF based on the mechanism model and the black-box model was established. The heat transfer mechanism model was firstly estab-lished according to the energy conservation law. In addition, the black-box model based on partial least squares was adopted to solve the problem that the regeneration of the ladle lining and thermal effects of the alloys are difficult to accurately calculate. Finally, the two models were combined to predict the end-point temperature of molten steel in LF. Simulation results show that the hit rate within the error range of ±5℃ by partial least squares for the regeneration of ladle lining refractory and thermal effects of the alloys reaches more than 97%, and the total hit rate within the error ranges of ±5, ±8 and ±10℃ by gray-box model reaches 88%, 96% and 99%, respectively. This means the grey-box model can accurately predict the end-point temperature of LF, which provides the guid-ance for the LF refining process in this factory.

The changes of total oxygen(T. O.) and N contents,the evolution of non-metallic inclusions,and the characteristic of macro-inclusions in casting billets of 50 CrVA spring steel produced by the BOF-LF-CC process were studied by continuous sampling at different stages. Results show that the average contents of T. O. and N are 106×10-6 and 13×10-6 at LF-start,respectively,and they become 15×10-6 and 39×10-6 in billets,indicating that the deoxidization effect in the LF refining process is obvious. However,reoxidation phenomenon is obvious in the transportation and casting processes,so it is necessary to strengthen the steel stream protection from ladle to tundish. The CaO-Al2O3-MgO and CaO-Al2O3-SiO2 composite oxide inclusions are the main inclusions in billets,the Al2O3 content in those inclusions is as high as 60%-70%,and no low-melting inclusion is obtained. The low-melting inclusion can be obtained by increasing the slag basicity or feeding a proper content of Ca wire. Large-size inclusions are primarily composed of CaO and CaOAl2O3-SiO2-(MgO) spherical oxides as well as a certain proportion of pure Al2O3 inclusions. It is necessary to extend the soft stirring time in the ladle to make inclusions float fully.

A novel composite phase change materials (PCMs) of paraffin/TiO2/active-carbon was prepared by a microemulsion method, where paraffin acted as a PCM and titanium dioxide (TiO2) as matrix material, and a small amount of active carbon was added to improve the thermal conductivity. The compositions, morphology and thermal properties of the paraffin/TiO2/active-carbon composite PCMs were characterized by XRD, SEM, TGA and DSC respectively. The shape stability during phase change process of this composite was also tested. The results show that paraffin is well encapsulated by TiO2 matrix, and thus exhibiting excellent shape-stabilized phase change feature. Besides, this composite PCM also presents superhydrophobic property. Therefore, these multifunctional features will endow PCMs with important application potential in energy efficient buildings.

The static tensile behaviors of Fe-22Mn-0.7C TWIP steel and Q235 steel between 700 ℃ and 1300 ℃ were investigated by Gleeble-1500 thermo-mechanical simulator.The microstructure characteristic and fracture morphology were observed by optical microscopy,scanning electron microscopy,energy dispersive spectrometry and electron probe micro-analysis.The hot ductility and influenced mechanism were revealed based on the discussion of chemical composition,matrix phase volume fraction,grain size and solidification defects.It is found that the TWIP steel has a reduction in area lower than 40% in the temperature range of 700 ℃ to 1250 ℃,but its tensile strength is higher than that of Q235 steel.Fractographic results manifest intergranular fracture for the TWIP steel.Grain refinement and microsegregation descending in the TWIP steel are beneficial to increasing the hot ductility due to the improvement of matrix homogeneity.Besides,the tensile strength and reduction in area of the TWIP steel increase with increasing strain rate.

Large strain isothermal compression tests were carried out on a Gleeble-3800 thermal simulator to study the high temperature deformation behavior of Cr-Co-Mo-Ni gear steel. The constitutive equation and hot processing map of the steel were established based on experiment data. The results show that the flow stress decreases with increasing temperature,but increases with increasing strain rate. The flow stress can be described by the constitutive equation in a hyperbolic sine function and the averaged value of activation energy is 487.21 kJ·mol-1. The proper hot working regions shown by the hot processing map are the temperature of 1000-1100℃ and the strain rate of 0.1-1 s-1. In addition,the forging processes were simulated by finite element method based on the experiment,the effects of initial forging temperature and passes on the temperature and strain rate of forgings were analyzed,and the proper forging process parameters were obtained which are the initial forging temperature of 1000-1100℃ and the forging passes of 15.

N-ethyl-N-nitrosourea (ENU) mutagenesis is a powerful tool to generate mutants on a large scale efficiently, and to discover genes with novel functions at the whole-genome level in Caenorhabditis elegans, flies, zebrafish and mice, but it has never been tried in large model animals. We describe a successful systematic three-generation ENU mutagenesis screening in pigs with the establishment of the Chinese Swine Mutagenesis Consortium. A total of 6,770 G1 and 6,800 G3 pigs were screened, 36 dominant and 91 recessive novel pig families with various phenotypes were established. The causative mutations in 10 mutant families were further mapped. As examples, the mutation of SOX10 (R109W) in pig causes inner ear malfunctions and mimics human Mondini dysplasia, and upregulated expression of FBXO32 is associated with congenital splay legs. This study demonstrates the feasibility of artificial random mutagenesis in pigs and opens an avenue for generating a reservoir of mutants for agricultural production and biomedical research.

Shadow as a design element applied to architectural and landscape design, can embellish, foil, and even enhance the subject. The shadow can also make the design works full of vitality and characteristic. Based on the actual cases, this article analyses the effect of shadow on architecture and landscape, and reveals the special effect producing by shadow. The effects include breaking the visual limitation, enhancing the connotation and artistic conception of the design. Shadow can give people an unexpected artistic appeal and spiritual shock. And bring much richer experience and even much more deep thinking to people.

In this lab-scale simulation, the performance of aerated immobilized microbe (IM) in in-situ pond sedimentation remediation, and the microbial community was studied. It is known for the results that total organic matter (TOM), total nitrogen (TN) and total phosphorus (TP) in the sediment can be effectively reduced by aerated immobilized microbe technology. The polluted raw water, classified as inferior Class-Ⅴ according to the surface water environment quality standard (GB3838-2002), upgraded to Class-III in 30-days remediation with TOM, TN and TP removal rates of 33.35%, 43.35% and 23.20%, respectively. In contract, the control group without the assistant of aerated immobilized microbe still remains at Class-IV. High-throughput sequencing analysis reveals that immobilized microbe technology could improve the species diversity and abundance of the flora, and enhance the similarity between the sediment and the overlying water in the system. The dominant bacteria of the overlying water were Perlucidibaca, Limnohabitans, Bacillus, Hydrogenophaga, Mycobacterium etc. And the dominant bacteria of the sediment were Methanolinea, Methanoregula, Candidatus Competibacter, Methanosaeta etc. Total phosphorous, certified by the redundancy analysis, is the key environmental factor of microbial community structure in both overlying water and sediment.

Genetically modified pigs have become a popular model system in fundamental research, agricultural and biomedical applications. However, random integration often result in unstable expression of transgene and unpredictable phenotypes. The Rosa26 locus has been widely used to produce genetic modified animals with high and consistent expressing of transgene in mouse, human and rat, as it can be targeted efficiently and is not subject to gene-silencing effects. Recently, the first case of reporter gene targeting pigs in porcine Rosa26 (pRosa26) locus was reported. In the study, full sequence of pRosa26 locus was further characterized, and the pRosa26 promoter (pR26) was cloned and we evidenced that the new porcine endogenous promoter is suitable for driving transgene expression in a high and stable manner by avoiding DNA methylation. Furthermore, elongation factor 1a promoter (EF1a) -driven GFP reporter and Myostatin promoter (MyoP)-driven Follistatin (Fst) were successfully targeted into the pRosa26 locusby traditional homologous recombination (HR) strategy. EF1a showed high activity and hypomethylation at the locus. And, muscle-specific promoter MyoP was activated strictly in muscle of the pRosa26 targeted pigs, indicating Rosa26 locus supports tissue-specific promoter driving transgene expression in its own manner. The study provided further demonstration on biomedical and agricultural applications of porcine Rosa26 promoter and locus.

Residue management in cropping systems is useful to improve soil quality. However, the studies on the effects of residue management on the enzyme activities and microbial community of soils in South China are few. Therefore, the effects of incorporating winter cover crop residue with a double-cropping rice (Oryza sativa L.) system on soil enzyme activities and microbial community in Southern China fields were studied. The experiment has conducted at the experimental station of the Institute of Soil and Fertilizer Research, Hunan Academy of Agricultural Science, China since winter 2004. Four winter cropping systems were used: rice-rice-ryegrass (Lolium multiflorum L.) (R-R-Ry), rice-rice-Chinese milk vetch (Astragalus sinicus L.) (R-R-Mv), rice-rice-rape (Brassica napus L.) (R-R-Ra) and rice-rice with winter fallow (R-R-Fa). The result indicated that the enzyme activities in the R-R-Ry, R-R-Mv and R-R-Ra systems were significantly higher (P