Background Methane(CH_(4))emissions from ruminants significantly contribute to greenhouse gas effects and energy loss in livestock production.Methyl-coenzyme M reductase(MCR)is the key enzyme in methanogenesis,making ...Background Methane(CH_(4))emissions from ruminants significantly contribute to greenhouse gas effects and energy loss in livestock production.Methyl-coenzyme M reductase(MCR)is the key enzyme in methanogenesis,making it a promising target for CH_(4) mitigation.This study aimed to identify and validate plant-derived inhibitors by using molecular docking to screen compounds with strong binding affinity to the F430 active site of MCR and assessing their efficacy in reducing CH_(4) emissions.Results Molecular docking analysis identified salvianolic acid C(SAC)as a potent inhibitor of MCR,showing a strong binding affinity to the F430 active site(binding energy:-8.2 kcal/mol).Enzymatic inhibition assays confirmed its inhibitory effect,with a half-maximal inhibitory concentration(IC50)of 692.3μmol/L.In vitro rumen fermentation experiments demonstrated that SAC supplementation(1.5 mg/g DM)significantly reduced CH_(4)production(P<0.01)without negatively affecting major fermentation parameters.Microbial community analysis using 16S rRNA sequencing and metagenomics revealed that SAC selectively altered the rumen microbiota,increasing the relative abundance of Bacteroidota while significantly reducing Methanobrevibacter(P=0.04).Moreover,metagenomic analysis showed the downregulation of key methanogenesis-related genes(mcrA and rnfC),suggesting a dual mechanism involving direct enzymatic inhibition and microbial community modulation.Conclusions These findings indicate that SAC effectively reduces CH_(4)production by inhibiting MCR activity and reshaping the rumen microbial community.As a plant-derived compound with strong inhibitory effects on methanogenesis,SAC presents a promising and sustainable alternative to synthetic CH_(4) inhibitors,offering potential applications for mitigating CH_(4)emissions in livestock production.展开更多
“好房子”承载着千家万户对美好生活的向往,2025年被首次写入政府工作报告,住房城乡建设部及各地行业主管部门相继对“好房子”建设提出了一系列要求,并持续推动政策落地,建设“好房子”由此成为房地产领域产业转型发展的新赛道。在此...“好房子”承载着千家万户对美好生活的向往,2025年被首次写入政府工作报告,住房城乡建设部及各地行业主管部门相继对“好房子”建设提出了一系列要求,并持续推动政策落地,建设“好房子”由此成为房地产领域产业转型发展的新赛道。在此背景下,由贝壳集团旗下贝好家推出的C2M(Customer to Manufacturer,从消费者到制造者)全链解决方案,经过一段时间的探索和落地实践,已取得不错的实践成效和市场反馈。展开更多
The airborne electromagnetic （AEM） method has a high sampling rate and survey flexibility. However, traditional numerical modeling approaches must use high-resolution physical grids to guarantee modeling accuracy, e...The airborne electromagnetic （AEM） method has a high sampling rate and survey flexibility. However, traditional numerical modeling approaches must use high-resolution physical grids to guarantee modeling accuracy, especially for complex geological structures such as anisotropic earth. This can lead to huge computational costs. To solve this problem, we propose a spectral-element （SE） method for 3D AEM anisotropic modeling, which combines the advantages of spectral and finite-element methods. Thus, the SE method has accuracy as high as that of the spectral method and the ability to model complex geology inherited from the finite-element method. The SE method can improve the modeling accuracy within discrete grids and reduce the dependence of modeling results on the grids. This helps achieve high-accuracy anisotropic AEM modeling. We first introduced a rotating tensor of anisotropic conductivity to Maxwell＇s equations and described the electrical field via SE basis functions based on GLL interpolation polynomials. We used the Galerkin weighted residual method to establish the linear equation system for the SE method, and we took a vertical magnetic dipole as the transmission source for our AEM modeling. We then applied fourth-order SE calculations with coarse physical grids to check the accuracy of our modeling results against a 1D semi-analytical solution for an anisotropic half-space model and verified the high accuracy of the SE. Moreover, we conducted AEM modeling for different anisotropic 3D abnormal bodies using two physical grid scales and three orders of SE to obtain the convergence conditions for different anisotropic abnormal bodies. Finally, we studied the identification of anisotropy for single anisotropic abnormal bodies, anisotropic surrounding rock, and single anisotropic abnormal body embedded in an anisotropic surrounding rock. This approach will play a key role in the inversion and interpretation of AEM data collected in regions with anisotropic geology.展开更多
The LiMnPO4/C composite material was synthesized via a sol-gel method based on the citric acid. The X-ray diffraction （XRD）, scanning electron microscopy （SEM） and electrochemical performance tests were adopted to...The LiMnPO4/C composite material was synthesized via a sol-gel method based on the citric acid. The X-ray diffraction （XRD）, scanning electron microscopy （SEM） and electrochemical performance tests were adopted to characterize the properties of LiMnPO4/C. The XRD studies show that the pure olivine phase LiMnPO4 can be obtained at a low temperature of 500 °C. The SEM analyses illustrate that the citric acid used as the chelating reagent and carbon source can restrain the particle size of LiMnPO4/C well. The LiMnPO4/C sample synthesized at 500 °C for 10 h performs the highest initial discharge capacity of 122.6 mA-h/g, retaining 112.4 mA-h/g over 30 cycles at 0.05C rate. The citric acid based sol-gel method is favor to obtain the high electrochemical performance of LiMnPO4/C.展开更多
Nanosphere-like Li2FeSiO4/C was synthesized via a solution method using sucrose as carbon sources under a mild condition of time-saving and energy-saving, followed by sintering at high temperatures for crystallization...Nanosphere-like Li2FeSiO4/C was synthesized via a solution method using sucrose as carbon sources under a mild condition of time-saving and energy-saving, followed by sintering at high temperatures for crystallization. The amount of carbon in the composite is less than 10% （mass fraction）, and the X-ray diffraction result confirms that the sample is of pure single phase indexed with the orthorhombic Pmn21 space group. The particle size of the Li2FeSiO4/C synthesized at 700 °C for 9 h is very fine and spherical-like with a size of 200 nm. The electrochemical performance of this material, including reversible capacity, cycle number, and charge-discharge characteristics, were tested. The cell of this sample can deliver a discharge capacity of 166 mA-h/g at C/20 rate in the first three cycles. After 30 cycles, the capacity decreases to 158 mA-h/g, and the capacity retention is up to 95%. The results show that this method can prepare nanosphere-like Li2FeSiO4/C composite with good electrochemical performance.展开更多
The objective of the present study was to examine the effect of different weaning methods on the ruminal methanogenic archaea composition and diversity in Holstein calves.Thirty-six newborn Holstein bull calves were a...The objective of the present study was to examine the effect of different weaning methods on the ruminal methanogenic archaea composition and diversity in Holstein calves.Thirty-six newborn Holstein bull calves were assigned to 1 of 3 treatments:(1)conventional weaning(d 56)and fed a high proportion of solid feed(CWS);(2)conventional weaning(d 56)and fed a high proportion of liquid feed(CWL);(3)early weaning(d 42)and fed with a high proportion of solid feed(EWS).High-throughput sequencing of the methyl coenzyme M reductase(mcr A)gene,which encodes theα-subunit of methyl coenzyme M reductase-the enzyme that catalyzes the final step in methanogenesis was used to determine the composition and diversity of rumen methanogens.No significant difference(P>0.05)was observed for operational taxonomic units(OTUs)or richness indices,but diversity indices increased(P<0.05)for calves fed high dietary solids.Predominant families across the three treatments were Methanobacteriaceae,Thermoplasmataceae and Methanomassiliicoccaceae.Calves in the EWS treatment had a higher(P<0.05)relative abundance of Methanobrevibacter sp.strain AbM4 and Methanosphaera stadtmanae,while calves in the CWL treatment had a higher(P<0.05)abundance of Methanosphaera sp.strain SM9.A positive(P<0.05)relationship was identified between butyrate and Methanobrevibacter sp.strain AbM4.In conclusion,the composition and diversity of methanogens in the rumen of Holstein calves varied under the different weaning methods.This study identified a positive relationship between butyrate and Methanobrevibacter sp.strain AbM4,potentially reflecting correlations between ruminal fermentation variables and methanogenesis function.These in-depth analyses provide further understanding of weaning methods for intensified production systems.展开更多
基金funded by the Integrated Demonstration of Scalable and Efficient Healthy Breeding for Cattle and Sheep(Grant No.2022YFD1301100)Instant Intelligent Diagnosis and Risk Warning Methods for Nutritional and Metabolic-Type Periparturient Cow Paralysis(Grant No.2024-YWF-ZYSQ-10)。
文摘Background Methane(CH_(4))emissions from ruminants significantly contribute to greenhouse gas effects and energy loss in livestock production.Methyl-coenzyme M reductase(MCR)is the key enzyme in methanogenesis,making it a promising target for CH_(4) mitigation.This study aimed to identify and validate plant-derived inhibitors by using molecular docking to screen compounds with strong binding affinity to the F430 active site of MCR and assessing their efficacy in reducing CH_(4) emissions.Results Molecular docking analysis identified salvianolic acid C(SAC)as a potent inhibitor of MCR,showing a strong binding affinity to the F430 active site(binding energy:-8.2 kcal/mol).Enzymatic inhibition assays confirmed its inhibitory effect,with a half-maximal inhibitory concentration(IC50)of 692.3μmol/L.In vitro rumen fermentation experiments demonstrated that SAC supplementation(1.5 mg/g DM)significantly reduced CH_(4)production(P<0.01)without negatively affecting major fermentation parameters.Microbial community analysis using 16S rRNA sequencing and metagenomics revealed that SAC selectively altered the rumen microbiota,increasing the relative abundance of Bacteroidota while significantly reducing Methanobrevibacter(P=0.04).Moreover,metagenomic analysis showed the downregulation of key methanogenesis-related genes(mcrA and rnfC),suggesting a dual mechanism involving direct enzymatic inhibition and microbial community modulation.Conclusions These findings indicate that SAC effectively reduces CH_(4)production by inhibiting MCR activity and reshaping the rumen microbial community.As a plant-derived compound with strong inhibitory effects on methanogenesis,SAC presents a promising and sustainable alternative to synthetic CH_(4) inhibitors,offering potential applications for mitigating CH_(4)emissions in livestock production.
文摘“好房子”承载着千家万户对美好生活的向往,2025年被首次写入政府工作报告,住房城乡建设部及各地行业主管部门相继对“好房子”建设提出了一系列要求,并持续推动政策落地,建设“好房子”由此成为房地产领域产业转型发展的新赛道。在此背景下,由贝壳集团旗下贝好家推出的C2M(Customer to Manufacturer,从消费者到制造者)全链解决方案,经过一段时间的探索和落地实践,已取得不错的实践成效和市场反馈。
基金financially supported by the Key Program of National Natural Science Foundation of China(No.41530320)China Natural Science Foundation for Young Scientists(No.41404093)+1 种基金Key National Research Project of China(Nos2016YFC0303100 and 2017YFC0601900)China Natural Science Foundation(No.41774125)
文摘The airborne electromagnetic （AEM） method has a high sampling rate and survey flexibility. However, traditional numerical modeling approaches must use high-resolution physical grids to guarantee modeling accuracy, especially for complex geological structures such as anisotropic earth. This can lead to huge computational costs. To solve this problem, we propose a spectral-element （SE） method for 3D AEM anisotropic modeling, which combines the advantages of spectral and finite-element methods. Thus, the SE method has accuracy as high as that of the spectral method and the ability to model complex geology inherited from the finite-element method. The SE method can improve the modeling accuracy within discrete grids and reduce the dependence of modeling results on the grids. This helps achieve high-accuracy anisotropic AEM modeling. We first introduced a rotating tensor of anisotropic conductivity to Maxwell＇s equations and described the electrical field via SE basis functions based on GLL interpolation polynomials. We used the Galerkin weighted residual method to establish the linear equation system for the SE method, and we took a vertical magnetic dipole as the transmission source for our AEM modeling. We then applied fourth-order SE calculations with coarse physical grids to check the accuracy of our modeling results against a 1D semi-analytical solution for an anisotropic half-space model and verified the high accuracy of the SE. Moreover, we conducted AEM modeling for different anisotropic 3D abnormal bodies using two physical grid scales and three orders of SE to obtain the convergence conditions for different anisotropic abnormal bodies. Finally, we studied the identification of anisotropy for single anisotropic abnormal bodies, anisotropic surrounding rock, and single anisotropic abnormal body embedded in an anisotropic surrounding rock. This approach will play a key role in the inversion and interpretation of AEM data collected in regions with anisotropic geology.
基金Project (0991025) supported by Natural Science Foundation of Guangxi, ChinaProject (51164007) supported by the National Natural Science Foundation of ChinaProject (201101ZD008) supported by Educational Commission of Guangxi, China
文摘The LiMnPO4/C composite material was synthesized via a sol-gel method based on the citric acid. The X-ray diffraction （XRD）, scanning electron microscopy （SEM） and electrochemical performance tests were adopted to characterize the properties of LiMnPO4/C. The XRD studies show that the pure olivine phase LiMnPO4 can be obtained at a low temperature of 500 °C. The SEM analyses illustrate that the citric acid used as the chelating reagent and carbon source can restrain the particle size of LiMnPO4/C well. The LiMnPO4/C sample synthesized at 500 °C for 10 h performs the highest initial discharge capacity of 122.6 mA-h/g, retaining 112.4 mA-h/g over 30 cycles at 0.05C rate. The citric acid based sol-gel method is favor to obtain the high electrochemical performance of LiMnPO4/C.
基金Project supported by Ministry of Education Key Laboratory of Synthetic and Natural Functional Molecular Chemistry, China Project (2010JK765) supported by the Education Department of Shaanxi Province, China
文摘Nanosphere-like Li2FeSiO4/C was synthesized via a solution method using sucrose as carbon sources under a mild condition of time-saving and energy-saving, followed by sintering at high temperatures for crystallization. The amount of carbon in the composite is less than 10% （mass fraction）, and the X-ray diffraction result confirms that the sample is of pure single phase indexed with the orthorhombic Pmn21 space group. The particle size of the Li2FeSiO4/C synthesized at 700 °C for 9 h is very fine and spherical-like with a size of 200 nm. The electrochemical performance of this material, including reversible capacity, cycle number, and charge-discharge characteristics, were tested. The cell of this sample can deliver a discharge capacity of 166 mA-h/g at C/20 rate in the first three cycles. After 30 cycles, the capacity decreases to 158 mA-h/g, and the capacity retention is up to 95%. The results show that this method can prepare nanosphere-like Li2FeSiO4/C composite with good electrochemical performance.
基金supported by the Key Program for International S&T Cooperation Projects of China(2016YFE0109000)the National Key R&D Program of China(2017YFF0211702)+1 种基金the National Natural Science Foundation of China(41475126 and 31802085)the Young Scientist Lifting Project,China(2017–2019)
文摘The objective of the present study was to examine the effect of different weaning methods on the ruminal methanogenic archaea composition and diversity in Holstein calves.Thirty-six newborn Holstein bull calves were assigned to 1 of 3 treatments:(1)conventional weaning(d 56)and fed a high proportion of solid feed(CWS);(2)conventional weaning(d 56)and fed a high proportion of liquid feed(CWL);(3)early weaning(d 42)and fed with a high proportion of solid feed(EWS).High-throughput sequencing of the methyl coenzyme M reductase(mcr A)gene,which encodes theα-subunit of methyl coenzyme M reductase-the enzyme that catalyzes the final step in methanogenesis was used to determine the composition and diversity of rumen methanogens.No significant difference(P>0.05)was observed for operational taxonomic units(OTUs)or richness indices,but diversity indices increased(P<0.05)for calves fed high dietary solids.Predominant families across the three treatments were Methanobacteriaceae,Thermoplasmataceae and Methanomassiliicoccaceae.Calves in the EWS treatment had a higher(P<0.05)relative abundance of Methanobrevibacter sp.strain AbM4 and Methanosphaera stadtmanae,while calves in the CWL treatment had a higher(P<0.05)abundance of Methanosphaera sp.strain SM9.A positive(P<0.05)relationship was identified between butyrate and Methanobrevibacter sp.strain AbM4.In conclusion,the composition and diversity of methanogens in the rumen of Holstein calves varied under the different weaning methods.This study identified a positive relationship between butyrate and Methanobrevibacter sp.strain AbM4,potentially reflecting correlations between ruminal fermentation variables and methanogenesis function.These in-depth analyses provide further understanding of weaning methods for intensified production systems.
