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In the avian species, genetic modification by cell nuclear transfer is infeasible due to its unique reproductive system. The in vitro primordial germ cell modification approach is difficult and cumbersome, although it is the main method of genetic modification in chickens. In the present study, the adenoviral CRISPR/Cas9 vector was directly microinjected into the dorsal aorta of chicken embryos to achieve in vivo genetic modification. The results demonstrated that keratin 75-like 4 (KRT75L4), a candidate gene crucial for feather development, was widely knocked out, and an 8bp deletion was the predominant mutation that occurred in multiple tissues in chimeras, particularly in the gonad (2.63-11.57%). As we expected, significant modification was detected in the sperm of G0 (0.16-4.85%), confirming the potential to generate homozygous chickens and establishing this vector as a simple and effective method for genetic modification in avian species.
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Adenoviridae , Aorta , Sistemas CRISPR-Cas , Pollos , Vectores Genéticos , Animales , Embrión de Pollo , Vectores Genéticos/genética , Pollos/genética , Adenoviridae/genética , Aorta/metabolismo , Edición Génica/métodos , MasculinoRESUMEN
Methanol-to-olefin (MTO) is a typical new coal chemical industry example. Due to the large volume of generated wastewater, complex composition including catalysts, aromatics and various oxygen-containing compounds, and serious environmental hazard, wastewater recycling is critical for sustainable industrial development and ecological protection. Herein, a swirl regenerating micro-channel separation (SRMS) technology was proposed to integrate deep filtration and hydrocyclone-enhanced regeneration. A small-scale experimental investigation was first conducted to verify the feasibility of the MTO wastewater treatment. A pilot SRMS device with a treatment capacity of 20 m3/h was constructed, and the device's continuous operation effect and stability were comprehensively evaluated. The separation performance of the SRMS device at different solution pH values and the impact of the hydrocyclone-enhanced regeneration of separation media were discussed in detail. At low solution pH values (<7), the SRMS device exhibits an average separation efficiency of 92.0% for fine particulate matter in wastewater, and the median particle size, d50, decreases from 1.55 to 0.6 µm. As the solution pH increases, the repulsive energy barrier for the medium-contaminant and contaminant-contaminant increases, inhibiting the deposition behavior of particulate pollutants. In addition, hydrocyclone desorbs contaminants deposited on the separation media and the average contaminant residual rate decreases from 3.3 to 0.2 wt%. We propose an industrial application for treating and reusing MTO wastewater (200 m3/h) using the SRMS technology based on the experimental results. The costs of the wastewater treatment process are as low as 0.25 CNY/m3, and the wastewater reuse rate is over 97% without chemical consumption. This work can provide an environmentally friendly and economically sustainable approach to the source management of MTO wastewater.
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Metanol , Aguas Residuales , Alquenos , Carbón Mineral , PolvoRESUMEN
The slow kinetics and poor structural stability prevent transition metal selenides from being widely used in sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs). Herein, the "flower-like" porous carbon anchored by Zn-Mn binary selenides (ZMS@FC) composites are fabricated by selenizing the modified hierarchically metal-organic frameworks. The 2D conductive hierarchically flakes' abundant pore structure and multiple active sites shorten the ion diffusion length and promote conductivity, while the synergistic effect of the binary metals and intrinsic large pseudocapacitive contribution effectively improve capacity and rate performance. ZMS@FC composites exhibit impressive rate capability of 294.4 mA h g-1 at 10 A g-1 and excellent cyclic stability with 369.6 mA h g-1 specific capacity retention at 2 A g-1 after 1000 cycling in SIBs. It is noted that 156.9 mA h g-1 can be retained at 5 A g-1 and 227.0 mA h g-1 is remained after 500 cycles at 2 A g-1 in PIBs. The ex situ X-ray diffraction patterns and transmission electron microscopy pictures are used to confirm the conversion reaction processes of the Zn-Mn-Se. Designing high-performance energy storage materials may benefit greatly from the universal synthesis technology of bimetallic sulfide anodes for enhanced SIBs and PIBs.
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Although the spontaneous vapor-solid growth of SiC nanowires is a well-established phenomenon, the exact mechanism by which nanowires grow on substrates is still poorly understood. Here, we studied the initial growth of SiC nanowires on carbon sources with different nanotextures via a catalyst-free vapor reaction between a polyacrylonitrile-based carbon fiber and a silicon powder. The results revealed that the SiC nanowires were preferentially formed on the carbon fiber with a higher degree of graphitization. Detailed analyses suggested that the growth behavior of the underlying SiC film formed on the carbon fibers, which is strongly affected by the microstructures of the carbon fibers, plays an important role in the formation of nanowires. In addition, the photoluminescence spectrum of SiC nanowires showed strong ultraviolet-visible emission peaks at an excitation wavelength of 250 nm, which may provide potential applications in the field of optoelectronic devices.
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ACF/GO/PEI (activated carbon fiber/graphene oxide/polyethyleneimine) composite was fabricated by crosslinking reaction and characterized with Scanning electron microscope (SEM), N2 physical adsorption and Fourier transform infrared spectroscopy (FTIR). Furthermore, the adsorption behavior of ACF/GO/PEI composite for methyl orange (MO) from aqueous solution was investigated. The experimental results showed that the specific surface area of ACF/GO/PEI composite is 1013.6 m2/g and almost the same as that of original ACFs. However, with a larger fraction of mesopores, the pore structure of ACF/GO/PEI composite showed a significant change in comparison with that of original ACFs. Accordingly, ACF/GO/PEI composite indicated more excellent adsorptivity than ACFs. The tests also showed the adsorption capacity decreased with the increase in adsorbent mass and pH. The adsorption isotherm was fitted using both Langmuir and Freundlich adsorption models and the adsorption process was found to be well-described by Langmuir model. Moreover, the adsorption kinetics was discussed with pseudo-first-order, pseudo-second-order and intra-particle diffusion models and the results disclosed the kinetic data were well fitted with pseudo-second-order kinetic model and the adsorption rate was controlled by intra-particle diffusion and film diffusion. Thermodynamic parameters including ΔG, ΔH and ΔS showed that the adsorption process was a spontaneous, endothermic and increasing randomness process.
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Single nucleotide polymorphisms (SNPs) are essential to the understanding of population genetic variation and diversity. Here, we performed restriction-site-associated DNA sequencing (RAD-seq) on 72 individuals from 13 Chinese indigenous and three introduced chicken breeds. A total of 620 million reads were obtained using an Illumina Hiseq2000 sequencer. An average of 75,587 SNPs were identified from each individual. Further filtering strictly validated 28,895 SNPs candidates for all populations. When compared with the NCBI dbSNP (chicken_9031), 15,404 SNPs were new discoveries. In this study, RAD-seq was performed for the first time on chickens, implicating the remarkable effectiveness and potential applications on genetic analysis and breeding technique for whole-genome selection in chicken and other agricultural animals.
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Pollos/genética , Técnicas de Genotipaje/métodos , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN/métodos , Animales , GenotipoRESUMEN
The atomic-scale nucleation mechanism of vapor-grown carbon nanofibers (CNFs) is investigated using classical molecular dynamics simulations with a developed parameterization. Carbon precipitation and graphene plane formation are simulated, taking into account the carbon concentration (CC) in Ni carbide. The simulated results show that the carbon atoms formed sp(2) networks or sp chains in the Ni nanocrystals and then precipitated onto the Ni surface with distinct precipitation dynamics and time intervals that are dependent on the CC. The lowest-energy configurations of the precipitated carbon atoms exhibit an irregular corrugated network, a defective graphene plane, and separate defective graphene planes under high, medium, and low CC, respectively. These observations are in good agreement with the microstructural characteristics of different types of CNFs from experiments. Pair correlation function calculations show that the precipitated carbon structures exhibit different graphite orderings. The study reveals the atomistic CNF nucleation mechanism and emphasizes the critical role of metal carbide CC in the microstructure formation of CNFs during synthesis.
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HfCxN1-x nanoparticles were synthesized using the urea-glass route, employing hafnium chloride, urea, and methanol as raw materials. The synthesis process, polymer-to-ceramic conversion, microstructure, and phase evolution of HfCxN1-x/C nanoparticles were thoroughly investigated across a wide range of molar ratios between the nitrogen source and the hafnium source. Upon annealing at 1600 °C, all precursors demonstrated remarkable translatability to HfCxN1-x ceramics. Under high nitrogen source ratios, the precursor exhibited complete transformation into HfCxN1-x nanoparticles at 1200 °C, with no observed presence of oxidation phases. In comparison to HfO2, the carbothermal reaction of HfN with C significantly reduced the preparation temperature required for HfC. By increasing the urea content in the precursor, the carbon content of the pyrolyzed products increased, leading to a substantial decrease in the electrical conductivity of HfCxN1-x/C nanoparticle powders. Notably, as the urea content in the precursor increased, a significant decrease in average electrical conductivity values was observed for the R4-1600, R8-1600, R12-1600, and R16-1600 nanoparticles measured at a pressure of 18 MPa, yielding values of 225.5, 59.1, 44.8, and 46.0 S·cm-1, respectively.
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Introduction: Pullorum disease is one of the common bacterial infectious diseases caused by Salmonella pullorum (S. pullorum), which can result in a decrease in the reproductive performance of laying hens, thus causing considerable economic losses. However, studies about the characteristics of intestinal microbiota with pullorum and their potential association with reproductive performance in hens are still limited. This study was to identify the gut microbiota associated with S. pullorum in poultry. Methods: A total of 30 hens with S. pullorum-negative (PN) and 30 hens with S. pullorum-positive (PP) were analyzed for hatching eggs laid in 2 weeks (HEL), fertilization eggs (FE), chick number (CN), and microbial structure. Results: There were significant differences in HEL (p < 0.01), FE (p < 0.01), and CN (p < 0.01) between PP and PN. Histomorphological observations showed abnormal morphology of the ovaries and fallopian tubes and low integrity of epithelial tissue in the ileum and cecum in PP. 16S rRNA gene sequencing revealed that beneficial cecal microbes, such as Bacteroides, Desulfovibrio, and Megamonas, were positively correlated with reproductive performance and had lower abundance in PP (p = 0.001). Furthermore, diminished phosphotransferase system (PTS) and pentose phosphate pathway, butanoate metabolism and oxidative phosphorylation were also found in PP. Discussion: Taken together, this study clarified the morphological characteristics of the reproductive tract and intestines of chickens infected with S. pullorum and preliminarily explored the potential association between cecal microbiota and reproductive performance in hens. Our data may provide a reference for revealing the intestinal microbial characteristics of hens in resisting pullorum and exploring novel approaches to infection control in future studies.
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Pullorum disease is one of the most common diarrhea-related diseases caused by Salmonella enterica subspecies enterica serovar Gallinarum biovar Pullorum (S Pullorum); it negatively affects the poultry industry. However, limited studies have explored the association between the gut microbiota and S Pullorum infection in chickens. In the present study, we performed a microbiome comparison and a microbiome genome-wide association study (mGWAS) to investigate the association among the host genetics, the gut microbiota, and pullorum disease in chickens. We found that S Pullorum infection in chickens could alter the abundance of 39 bacterial genera (P < 0.05). The altered structure and composition of the gut microbiota were also detected in the offspring. mGWAS results revealed host genetic variants to be prominently associated with gut microbial diversity and individual microbes. The pathogens Pelomonas and Brevundimonas, which had a high abundance in positive parent chickens and their offspring, were significantly associated with several genetic mutations in immunity-related genes, such as TGIF1, TTLL12, and CCR7 This finding explained why Pelomonas and Brevundimonas were heritable in S Pullorum-infected chickens. The heritable gut microbes and identified genetic variants could provide references for the selection of resistant chickens and the elimination of pullorum disease.IMPORTANCE The present study investigated the association among the host genome, the gut microbiome, and S Pullorum infection in chickens. The results suggested that the gut microbial structure is altered in S Pullorum-infected chickens. The diversity and abundance of the gut microbiota remarkably differed between the offspring coming from S Pullorum-positive and S Pullorum-negative chickens. Heritable gut microbiota were detected in the offspring. Moreover, host genetic variants were associated with microbial diversity and individual gut microbes. The pathogens Pelomonas and Brevundimonas, which exhibited a high heritability in S Pullorum-positive parents and their offspring, were associated with several genetic mutations in immunity-related genes.
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The gut microbiota is a complex ecological community and widely recognized in many aspects of research, but little is known on the relation between gut microbiota and embryonic development in chickens. The aim of this study was to explore the dynamic distribution of gut microbiota in chickens' embryos during stages of developments (chicken embryos that had incubated until day 3 [E3], day 12 [E12], and day 19 [E19]). Here, 16S rRNA gene sequencing was performed on the gut microbiota in chicken embryos across different developmental stages. Twenty-one phyla and 601 genera were present in chicken embryos, and 96 genera such as Ochrobactrum, Phyllobacterium, and Amycolatopsis were the core microbiota in the 3 stages of development. Second, 94 genera of microbes were found to change significantly between E3 and E12, and 143 genera significantly differed between E12 and E19 in chicken embryos (P < 0.05). Ochrobactrum and Amycolatopsis decreased with growth changes: E3 (30.4%), E12 (25.1%), and E19 (13.6%) and E3 (11.5%), E12 (7.4%), and E19 (5.6%), respectively. Contrarily, Phyllobacterium increased to 47.9% at E19, indicating the growing trend of microbial diversity among the embryos' development. Moreover, the principal component analysis showed a high level of similarities between E3 and E12 compared with E19, whereas the alpha analysis showed more diversity of gut microbiota at E19. Furthermore, the functional predictions showed that metabolic pathways such as energy metabolism and genetic information processing were significantly enriched on day 3 and day 12 in our study, suggesting their strong influence on growth, development, and immunity of chicken embryos. Our findings provide insights into the understanding of dynamic shifts of gut microbiota during chicken embryonic growth.
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Fenómenos Fisiológicos Bacterianos , Biodiversidad , Pollos , Microbioma Gastrointestinal , Animales , Bacterias/genética , Embrión de Pollo , Pollos/microbiología , Desarrollo Embrionario , ARN Ribosómico 16S/genéticaRESUMEN
ZnSe nitrogen-doped carbon composite nanofibers (ZnSe@N-CNFs) were derived as anode materials from selenization of electrospinning nanofibers. Electron microscopy shows that ZnSe nanoparticles are distributed in electrospinning nanofibers after selenization. Electrochemistry tests were carried out and the results show the one-dimensional carbon composite nanofibers reveal a great structural stability and electrochemistry performance by the enhanced synergistic effect with ZnSe. Even at a current density of 2 A g-1, the as-prepared electrodes can still reach up to 701.7 mA h g-1 after 600 cycles in lithium-ion batteries and 368.9 mA h g-1 after 200 cycles in sodium-ion batteries, respectively. ZnSe@N-CNFs with long cycle life and high capacity at high current density implies its promising future for the next generation application of energy storage.
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Novel carbon-free Mn2O3/MnCr2O4 hybrid nanosheets are synthesized through thermal decomposition of the facilely co-precipitated Mn-Cr binary hydroxide and a carbonate hybrid precursor. As an anode for lithium-ion batteries, the Mn2O3/MnCr2O4 electrode delivers a wonderful electrochemical performance, i.e., an enhanced stability of 913 mA h g-1 at a current density of 1 A g-1 after 300 cycles, and an excellent rate performance. The excellent electrochemical performance of the Mn2O3/MnCr2O4 electrode can be ascribed to the interconnected nanosheets and porous structure, as well as the possible synergistic effects between Mn and Cr mixed oxides.
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Novel (B,N)-doped three-dimensional (3D) porous graphene-carbon nanotubes (CNTs) can be used as an excellent alkaline and acid tolerant electrocatalyst for both the oxygen reduction reaction (ORR) and the hydrogen evolution reaction (HER). Based on density functional theory, the H and O atoms' pre-and post-adsorption energy can effectively reduce the reaction energy barrier.
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Polydactyly, a common heritable limb malformation in vertebrates, is characterized by supernumerary digits. In chickens, basic characteristics and rough dominant genes have been explored in past decades; however, the elaborate pattern of inheritance and the determinant gene remain obscure. In this study, different types of polydactylism were classified by the numbers and the shapes of toes, including the newly defined subtypes of B' and G, for the Beijing fatty chicken, a native breed of chicken from China. Through experiments on hybridization, we demonstrated a complete dominant inheritance of polydactyly instead of an incomplete penetrance or genetic modification of the previous conjecture. In particular, by using the F2 population of the five-digit purebred line of Beijing fatty chicken backcrossed to Shiqiza chicken and by using restriction-site associated DNA based markers, we performed a genome-wide association study on the trait of polydactyly. Furthermore, whole genome resequencing strategy was applied to sweep SNPs across the whole genome. An outlier-based Fst approach was employed to search for signatures of selection, and results indicated that the determinant mutation was found in the region ranging from 8.3 Mb to 8.7 Mb, where the polydactyly candidate gene LMBR1 was located. The G/T mutation of rs80659072 was identified to be highly associated with polydactyly in our resequencing and was validated in random samples from an expanded population. Thus, we confirmed that LMBR1 was the causative gene of polydactyly in the Beijing fatty chicken by using GWAS with restriction-site associated DNA based markers and resequencing.
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Pollos/genética , Mapeo Cromosómico , Polidactilia/genética , Animales , Genes Dominantes , Mutación , Polimorfismo de Nucleótido SimpleRESUMEN
PGCs (Primordial germ cells) were isolated from the blood of 51~56 h hatching Shiqiza chicken embryos by Ficoll density gradient centrifugation. The PGCs were injected into 2.5 d hatching embryos of H breed chicken to produce germ-line chimeras. AFLP checking method was established to identify chicken germline chimeras. Eight germ-line H-S chimera embryos were identified among 20 developing H breed embryos.
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Pollos , Quimera , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Animales , Células Cultivadas , Pollos/genética , Desarrollo Embrionario , Células GerminativasRESUMEN
The effect of mass transport on the growth characteristics of large-area vapor-grown carbon nanofibers (CNFs) was investigated by adjusting the substrate deposition angle (α). The catalyst precursor solution was coated onto one side of a 2D porous carbon paper substrate via a decal printing method. The results showed that the CNFs were grown on only one side of the substrate and α was found to significantly affect the growth uniformity. At α = 0°, the growth thickness, the density, the microstructure and the yield of the CNF film were uniform across the substrate surface, whereas the growth uniformity decreased with increasing α, suggesting that the large-area CNF deposition processes were mass-transport-controlled. Computational fluid dynamics simulations of the gas diffusion processes revealed the homogeneous distributions of the carbon-source-gas concentration, pressure, and velocity near the substrate surface at α = 0°, which were the important factors in achieving the mass-transport-limited uniform CNF growth. The homogeneity of the field distributions decreased with increasing α, in accordance with the variation in the growth uniformity with α. When used as a micro-porous layer, the uniform CNF film enabled higher proton exchange membrane fuel cell performance in comparison with commercial carbon black by virtue of its improved electronic and mass-transport properties confirmed by the electrochemical impedance spectroscopy results.