Chinese cabbage(Brassica rapa ssp. pekinensis) has a long cultivation history and is one of the vegetable crops with the largest cultivation area in China. However, salt stress severely damages photosynthesis and horm...Chinese cabbage(Brassica rapa ssp. pekinensis) has a long cultivation history and is one of the vegetable crops with the largest cultivation area in China. However, salt stress severely damages photosynthesis and hormone metabolism, nutritional balances, and results in ion toxicity in plants. To better understand the mechanisms of salt-induced growth inhibition in Chinese cabbage, RNA-seq and physiological index determination were conducted to explore the impacts of salt stress on carbon cycle metabolism and photosynthesis in Chinese cabbage. Here, we found that the number of thylakoids and grana lamellae and the content of starch granules and chlorophyll in the leaves of Chinese cabbage under salt stress showed a time-dependent response, first increasing and then decreasing. Chinese cabbage increased the transcript levels of genes related to the photosynthetic apparatus and carbon metabolism under salt stress, probably in an attempt to alleviate damage to the photosynthetic system and enhance CO_(2) fixation and energy metabolism. The transcription of genes related to starch and sucrose synthesis and degradation were also enhanced;this might have been an attempt to maintain intracellular osmotic pressure by increasing soluble sugar concentrations. Soluble sugars could also be used as potential reactive oxygen species(ROS) scavengers, in concert with peroxidase(POD)enzymes, to eliminate ROS that accumulate during metabolic processes. Our study characterizes the synergistic response network of carbon metabolism and photosynthesis under salt stress.展开更多
Balancing electron transfer and intermediate adsorption ability of bifunctional catalysts via tailoring electronic structures is crucial for green hydrogen production,while it still remains challenging due to lacking ...Balancing electron transfer and intermediate adsorption ability of bifunctional catalysts via tailoring electronic structures is crucial for green hydrogen production,while it still remains challenging due to lacking efficient strategies.Herein,one efficient and universal strategy is developed to greatly regulate electronic structures of the metallic Ni-Fe-P catalysts via in-situ introducing the rare earth(RE)atoms(Ni-Fe-RE-P,RE=La,Ce,Pr,and Nd).Accordingly,the as-prepared optimal Ni-Fe-Ce-P/CC self-supported bifunctional electrodes exhibited superior electrocatalytic activity and excellent stability with the low overpotentials of 247 and 331 mV at 100 mA cm^(-2) for HER and OER,respectively.In the assembled electrolyzer,the Ni-Fe-Ce-P/CC as bifunctional electrodes displayed low operation potential of 1.49 V to achieve a current density of 10 mA cm^(-2),and the catalytic performance can be maintained for 100 h.Experimental results combined with density functional theory(DFT)calculation reveal that Ce doping leads to electron decentralization and crystal structure distortion,which can tailor the band structures and d-band center of Ni-Fe-P,further increasing conductivity and optimizing intermediate adsorption energy.Our work not only proposes a valuable strategy to regulate the electron transfer and intermediate adsorption of electrocatalysts via RE atoms doping,but also provides a deep under-standing of regulation mechanism of metallic electrocatalysts for enhanced water splitting.展开更多
To investigate the dissolution behaviors of Al_(2)O_(3)inclusions in CaO-5wt%MgO-SiO_(2)-30wt%Al_(2)O_(3)-TiO_(2)system ladle slags,confocal scanning laser microscopy was conducted on the slags with different TiO_(2)c...To investigate the dissolution behaviors of Al_(2)O_(3)inclusions in CaO-5wt%MgO-SiO_(2)-30wt%Al_(2)O_(3)-TiO_(2)system ladle slags,confocal scanning laser microscopy was conducted on the slags with different TiO_(2)contents(0-10wt%),and scanning electron microscopy was performed to study the interfacial reaction between Al_(2)O_(3)and this slag system.The results disclose that the dissolution of Al_(2)O_(3)inclusions does not result in the formation of new phases at the boundary between the slag and the inclusions.In TiO_(2)-bearing and TiO_(2)-free ladle slags,there is no difference in the dissolution mechanism of Al_(2)O_(3)inclusions at steelmaking temperatures.Boundary layer diffusion is found as the controlling step of the dissolution of Al_(2)O_(3),and the diffusion coefficient is in the range of 4.18×10^(-10)to 2.18×10^(-9)m^(2)/s at 1450-1500℃.Compared with the solubility of Al_(2)O_(3)in the slags,slag viscosity and temperature play a more profound role in the dissolution of Al_(2)O_(3)inclusions.A lower viscosity and a lower melting point of the slags are beneficial for the dissolution.Suitable addition of TiO_(2)(e.g.,5wt%)in ladle slags can enhance the dissolution of Al_(2)O_(3)inclusions because of the low viscosity and melting point of the slags,while excessive addition of TiO_(2)(e.g.,10wt%)shows the opposite trend.展开更多
Based on low-altitude remote sensing images,this paper established sample set of typical river vegetation elements and proposed river vegetation extraction technical solution to adaptively extract typical vegetation e...Based on low-altitude remote sensing images,this paper established sample set of typical river vegetation elements and proposed river vegetation extraction technical solution to adaptively extract typical vegetation elements of river basins.The main research of this paper were as follows:(1)a typical vegetation extraction sample set based on low-altitude remote sensing images was established.(2)A low-altitude remote sensing image vegetation extraction model based on the focus perception module was designed to realize the end-to-end automatic extraction of different types of vegetation areas of low-altitude remote sensing images to fully learn the spectral spatial texture information and deep semantic information of the images.(3)By comparison with the baseline method,baseline method with embedded focus perception module showed an improvement in the precision by 7.37%and mIoU by 49.49%.Through visual interpretation and quantitative calculation analysis,the typical river vegetation adaptive extraction network has effectiveness and generalization ability,consistent with the needs of practical applications of vegetation extraction.展开更多
短串联重复序列(short tandem repeat,STR)已广泛用于法医学亲子鉴定和个体识别中,但STR的突变可能会影响其结果的解释。在大多数类似研究中,由于忽略“隐性”突变现象,STR的突变率被低估。鉴于此,为获得更加准确的STR实际突变率,本研...短串联重复序列(short tandem repeat,STR)已广泛用于法医学亲子鉴定和个体识别中,但STR的突变可能会影响其结果的解释。在大多数类似研究中,由于忽略“隐性”突变现象,STR的突变率被低估。鉴于此,为获得更加准确的STR实际突变率,本研究使用Slooten与Ricciardi提出的有限突变模型和大规模数据,对28,313例(78,739个体)中国北京汉族已确认亲生关系的亲子鉴定案的20个常染色体STR基因座(D3S1358、D1S1656、D13S317、Penta E、D16S539、D18S51、D2S1338、CSF1PO、Penta D、TH01、vWA、D21S11、D6S1043、D7S820、D5S818、TPOX、D8S1179、D12S391、D19S433和FGA;由于有限突变模型中未包含D6S1043的矫正参数,因此本文实际计算其余19个STR基因座的突变率)进行了调查。结果发现,所有基因座均存在突变现象,总计发生1665个突变事件,包括1614个一步突变,34个两步突变,8个三步突变和9个非整步突变。基因座特异性的平均实际突变率在三联体中为0.00007700(TPOX)~0.00459050(FGA),在二联体中为0.00000000(TPOX)~0.00344850(FGA)。此外,本研究还分析了表面和实际突变率、三联体和二联体突变率、父源和母源的突变率之间的关系。研究表明,实际突变率多大于表面突变率,而且μ1^(*)/μ2^(*)(表面突变率)的比值通常也大于μ1/μ2(实际突变率)(μ1^(*),μ1;μ2^(*),μ2分别是一步和两步的突变率),即更多的“隐性”突变被释放出来。而且父源和母源的三联体和二联体的突变率也有存在差异。随后,将这些突变率数据与已发表的中国其他汉族人口的相关研究进行比较,展现出了STR突变率的时间与区域差异。由于样本量大,本研究中还报告了一些少见的突变事件,例如同卵双胞胎突变和“假四步突变”等。综上所述,本研究通过大量数据获得了接近真实的STR突变率的估计值,不仅可为中国法医DNA数据库和群体遗传学数据库提供重要的基础数据,也对开展法医学个体识别、亲权鉴定和遗传学研究具有重要的意义。展开更多
Based on the investigation of long-life asphalt pavement at home and abroad,the development of long-life asphalt pavement technology in Shandong Province,China is reviewed in this paper.The structural combination char...Based on the investigation of long-life asphalt pavement at home and abroad,the development of long-life asphalt pavement technology in Shandong Province,China is reviewed in this paper.The structural combination char-acteristics of typical long-life asphalt pavement in Shandong Province and their popularization and application are introduced.The application effect of combined base long-life asphalt pavement,which has been widely promoted,is evaluated.At the same time,taking the Binda perpetual pavement test road in Shandong Province as an example,the dynamic response and long-term performance evolution of long-life asphalt pavement are analyzed over a period of more than 17 years.Sections S1,S2,and S3 present information about full-depth asphalt pavement.Section S4 describes combined base asphalt pavement.The results show that the maximum strain of S1–S4 is within the endurance strain limit.S1,S2,S3 and S4 are all expected to be long-life asphalt pavements.In the current study,Sections S1–S4 were maintained in good condition during a service period of more than 17 years with no structural cracks and good deflection,rutting,and IRI indexes.The deflection index was stable without growth,and the IRI was also relatively stable following the opening to traffic.The rutting depth un-derwent a slight cumulative increase within 8 years of opening,and then stabilized.The average rutting depth over the 17-year period was less than 15 mm.Therefore,S1–S4 meet the design standards required for use as long-life pavements.From the perspectives of resource saving,energy saving,and emission reduction and service performance,full-depth asphalt pavement can be considered to represent a new generation of green and durable pavement structures with great future promotion potential.展开更多
Objective:To systematically evaluate the clinical efficacy and safety of Qingkailing (QKL) injection for pediatric acute upper respiratory infection (AURI).Methods:We searched for randomized controlled trials (RCTs) o...Objective:To systematically evaluate the clinical efficacy and safety of Qingkailing (QKL) injection for pediatric acute upper respiratory infection (AURI).Methods:We searched for randomized controlled trials (RCTs) of pediatric AURI treated by QKL and western medicine (WM) in the China National Knowledge Infrastructure Database,China Science and Technology Journal Database,Wanfang,Chinese Biomedical Literature Database,PubMed and Cochrane Library from inception to August,2016.Two reviewers independently retrieved the RCTs and extracted information.The Cochrane Collaboration Risk of Bias Assessment Tool was used to evaluate the methodological quality of RCTs.The data were meta-analyzed by RevMan 5.3 software.Results:Ultimately,21 RCTs that involved 2364 participants were included,and the quality of RCTs was generally poor.According to the meta-analysis,the combined use of QKL and WM for treating AURI can be effective,with a higher total effective rate,less defervescence time and less recovery time of tonsil and throat inflammation.Twenty-five adverse drug reactions (ADRs) were reported in three RCTs,but there were no serious ADRs.Conclusion:The combination of QKL and WM for treating pediatric AURI can result in better effects,but no definitive conclusions can be made regarding its safety.More rigorous RCTs are needed to support the clinical application of QKL.展开更多
Solar-driven water splitting is a promising alternative to industrial hydrogen production.This study reports an elaborate design and synthesis of the integration of cadmium sulfi de(CdS)quantum dots and cuprous sulfi ...Solar-driven water splitting is a promising alternative to industrial hydrogen production.This study reports an elaborate design and synthesis of the integration of cadmium sulfi de(CdS)quantum dots and cuprous sulfi de(Cu_(2)S)nanosheets as three-dimensional(3D)hollow octahedral Cu_(2)S/CdS p-n heterostructured architectures by a versatile template and one-pot sulfi dation strategy.3D hierarchical hollow nanostructures can strengthen multiple refl ections of solar light and provide a large specifi c surface area and abundant reaction sites for photocatalytic water splitting.Owing to the construction of the p-n heterostructure as an ideal catalytic model with highly matched band alignment at Cu_(2)S/CdS interfaces,the emerging internal electric fi eld can facilitate the space separation and transfer of photoexcited charges between CdS and Cu_(2)S and also enhance charge dynamics and prolong charge lifetimes.Notably,the unique hollow Cu_(2)S/CdS architectures deliver a largely enhanced visible-light-driven hydrogen generation rate of 4.76 mmol/(g·h),which is nearly 8.5 and 476 times larger than that of pristine CdS and Cu_(2)S catalysts,respectively.This work not only paves the way for the rational design and fabrication of hollow photocatalysts but also clarifi es the crucial role of unique heterostructure in photocatalysis for solar energy conversion.展开更多
The agricultural and consumer quality of Chinese cabbage is determined by its shape.The shape is defined by the folding of the heading leaves,which defines the head top shape(HTS).The overlapping HTS,in which the head...The agricultural and consumer quality of Chinese cabbage is determined by its shape.The shape is defined by the folding of the heading leaves,which defines the head top shape(HTS).The overlapping HTS,in which the heading leaves curve inward and overlap at the top,is the shape preferred by consumers.To understand the genetic regulation of HTS,we generated a large segregating F 2 population from a cross between pak choi and Chinese cabbage,with phenotypes ranging from nonheading to heading with either outward curving or inward curving overlapping heading leaves.HTS was correlated with plant height,outer/rosette leaf length,and petiole length.A high-density genetic map was constructed.Quantitative trait locus(QTL)analysis resulted in the identification of 22 QTLs for leafy head-related traits,which included five HTS QTLs.Bulked segregant analysis(BSA)was used to confirm HTS QTLs and identify candidate genes based on informative single-nucleotide polymorphisms.Interestingly,the HTS QTLs colocalized with QTLs for plant height,outer/rosette leaf,and petiole length,consistent with the observed phenotypic correlations.Combined QTL analysis and BSA laid a foundation for molecular marker-assisted breeding of Chinese cabbage HTS and directions for further research on the genetic regulation of this trait.展开更多
With the complementation of whole-genome sequencing of Chinese cabbage,it is necessary to develop genome-wide Simple Sequence Repeat(SSR)markers and analyse their characteristics,which will bring a revolution in the m...With the complementation of whole-genome sequencing of Chinese cabbage,it is necessary to develop genome-wide Simple Sequence Repeat(SSR)markers and analyse their characteristics,which will bring a revolution in the molecular marker-assisted breeding of Chinese cabbage.In this study distribution and characteristics of SSR loci in the genome of Chinese cabbage'Chiifu'was analyzed.Finally,a total of 173,892 SSR markers that occurred in 10 chromosomes were identified,and Perfect Repeat Motifs(P type)which is a main form of SSR loci with a mean distance of 1.89 kb/SSR was identified.Among them,mono-,di-,and tri-nucleotide repeat motifs were equally distributed across chromosomes compared with tetra-,penta-,and hexa-nucleotide repeat motifs.The largest proportion of SSR loci consisted of mono-and dinucleotide repeat motifs,which accounted for 93.04%of the total SSR loci.A/T and AT/TA were the most abundant motifs,accounting for 97.61%and 64.05%of the mono-and dinucleotide repeats,respectively.Furthermore,200 SSR markers were used for the amplification of 12 Chinese cabbage germplasm,in which 30 were highly polymorphic.These SSR markers were further used for the association analyses of flowering time of 190 Chinese cabbage accessions.The results revealed that 9 and 10 alleles were associated with bolting and flowering time,respectivley.The results show that development of SSR markers is feasible and useful in marker assisted selection of Chinese cabbage.展开更多
Although China has achieved great advancements toward national food security,the country is still confronted with a range of challenges,including natural resource stress,imbalanced diets and environmental pollution.Op...Although China has achieved great advancements toward national food security,the country is still confronted with a range of challenges,including natural resource stress,imbalanced diets and environmental pollution.Optimized management of crop–livestock systems is the key measure to realize agricultural green transformation.However,optimized management of crop–livestock systems that use multi-objective zoning is lacking.This study employed a multi-objective zoning management approach to comprehensively analyze four indicators:ammonia volatilization,nitrogen surplus,soil carrying capacity and ecological red line area.With its significant ecological integrity and a strong emphasis on sustainability,the Baiyangdian Basin serves as a unique and suitable test case for conducting analyses on multi-objective nutrient optimization management,with the aim to facilitate the agricultural green transformation.This study finds that less than 8%of the area in the Baiyangdian Basin meet the acceptable environmental indicator standard,whereas around 50%of the area that had both nitrogen surplus and ammonia volatilization exceeded the threshold.Implementation of unified management,that is,the same management technique across the study areas,could result in an increase of areas meeting environmental indicator thresholds to 21.1%.This project developed a novel multi-indicator partition optimization method,in which distinct measures are tailored for different areas to satisfy multiple environmental indicators.Implementation of this method,could potentially bring more than 50%area below the threshold,and areas with ammonia emissions and nitrogen surplus could be reduced to 15.8%.The multi-indicators partition optimization method represents a more advanced and efficiency-oriented management approach when compared to unified management.This approach could be regarded as the best available option to help China achieve agricultural transformation to improve efficient production and reduce environmental pollution.It is recommended that current policies aimed at nutrient management toward sustainable agricultural development should shift toward the application of multi-indicators partition optimization.展开更多
A recent UN Sustainable Development Goals(SDGs) analysis indicated a significant regression in the global SDG goal scores, particularly in SDG 2—Zero Hunger. The emissions of environmental pollution caused by meeting...A recent UN Sustainable Development Goals(SDGs) analysis indicated a significant regression in the global SDG goal scores, particularly in SDG 2—Zero Hunger. The emissions of environmental pollution caused by meeting food demands have prompted some countries to intensify their climate change mitigation efforts. These circumstances have introduced significant uncertainty to the future global sustainable food development. Additionally, a notable global challenge is the persistence of hidden hunger, primarily characterized by the insufficient consumption of high-quality animal protein. Addressing this issue would necessitate increased environmental costs to attain high-quality food security. The future food system presents a significant challenge in coordinating food security, food quality and environmental quality. This article presents a comprehensive review and proposes a three-step strategy for future agricultural development based on food security, quality, and environmental aspects. This is a novel food system transfer strategy, as it concurrently addresses both global food security and environmental thresholds. It involves the construction of an efficient food system that operates within the constraints of environmental limits. The objective is to align with global SDG indicators and to maintain natural resource consumption and pollutant emissions within planetary boundaries.展开更多
Perovskite light-emitting diodes(PeLEDs)rely on optimized device architecture to realize effective electro-optical converting.Especially,the stacks of dissimilar semiconducting materials form heterointerfaces,at which...Perovskite light-emitting diodes(PeLEDs)rely on optimized device architecture to realize effective electro-optical converting.Especially,the stacks of dissimilar semiconducting materials form heterointerfaces,at which the defects and energetics of perovskite film greatly affect the device performance.Herein,we focus on the heterointerface engineering of perovskite towards high-quality PeLEDs.The defect engineering at both the bottom-surface(namely buried interface)and top-surface of perovskite film is simultaneously performed by semiconducting passivating molecules,which feature aligned energy levels and superior carrier injection ability regarding to perovskite.Moreover,such defect passivation could influence the heterointerface energetics.The perovskite work function is decreased by our suggested passivator treatment because of interface dipole,which results in band bending at the heterojunction and modulates the carrier dynamics.Hence,the electron injection is greatly enhanced,which boosts the up-conversion electroluminescence in current system.Overall,via the heterointerface engineering of defects and energetics synergistically,efficient PeLEDs with 3-fold enhancement of external quantum efficiency and low driving voltages with respect to pristine ones are achieved based on our proposed PeLED architecture.展开更多
Summary What is already known about this topic?Tuberculosis(TB)is often referred to as“a disease of poverty,”yet the information regarding the financial burden of TB care is limited and regionally representative.Wha...Summary What is already known about this topic?Tuberculosis(TB)is often referred to as“a disease of poverty,”yet the information regarding the financial burden of TB care is limited and regionally representative.What is added by this report?This manuscript reported the national representative total and breakdown costs associated with TB care in China.The total cost per patient was 1,185 USD,of which 88%was direct cost and 37%was incurred prior to TB treatment.展开更多
The performance of perovskite light-emitting diodes(PeLEDs)has been drastically improved recently.Therein,the coexistence of polydisperse perovskite domains has been one worthy subject of study.The crystallization of ...The performance of perovskite light-emitting diodes(PeLEDs)has been drastically improved recently.Therein,the coexistence of polydisperse perovskite domains has been one worthy subject of study.The crystallization of perovskite is affected by the buried interface character with the bottom contact layer;and the trap states also inherently exist at the buried interface of the perovskite film,which induce the nonradiative recombination and impede the PeLED performance.In this work,we focus on the crystallization modulation of monodisperse perovskite nanodomains toward high-performance PeLEDs.We show that a LiBr pre-modification layer on the bottom substrate induces the formation of monodisperse perovskite phase.In this system,the carrier transferring process deriving from the polydisperse phases is reduced.In addition,the LiBr pre-modification layer at the buried interface minimizes the trap states and enhances the radiative recombination of perovskites.Accordingly,our PeLEDs show a champion external quantum efficiency(EQE)of 25.5%for 4 mm2 device,and 22.9%for 100 mm^(2)device.展开更多
基金financially supported by the Natural Science Foundation of Hebei Province-Innovation Group Research Project(Grant No.C2020204111)the National Natural Science Foundation of China(Grant No.31930098)+3 种基金the Science Fund for Distinguished Young Scholars of Hebei Province(Grant No.C2021204049)the Hebei Province Outstanding Youth Fund(Grant No.BJ2021024)the Hebei Provincial Key Research Projects(21326344D)Hebei International Joint Research Base of Modern Agricultural Biotechnology.
文摘Chinese cabbage(Brassica rapa ssp. pekinensis) has a long cultivation history and is one of the vegetable crops with the largest cultivation area in China. However, salt stress severely damages photosynthesis and hormone metabolism, nutritional balances, and results in ion toxicity in plants. To better understand the mechanisms of salt-induced growth inhibition in Chinese cabbage, RNA-seq and physiological index determination were conducted to explore the impacts of salt stress on carbon cycle metabolism and photosynthesis in Chinese cabbage. Here, we found that the number of thylakoids and grana lamellae and the content of starch granules and chlorophyll in the leaves of Chinese cabbage under salt stress showed a time-dependent response, first increasing and then decreasing. Chinese cabbage increased the transcript levels of genes related to the photosynthetic apparatus and carbon metabolism under salt stress, probably in an attempt to alleviate damage to the photosynthetic system and enhance CO_(2) fixation and energy metabolism. The transcription of genes related to starch and sucrose synthesis and degradation were also enhanced;this might have been an attempt to maintain intracellular osmotic pressure by increasing soluble sugar concentrations. Soluble sugars could also be used as potential reactive oxygen species(ROS) scavengers, in concert with peroxidase(POD)enzymes, to eliminate ROS that accumulate during metabolic processes. Our study characterizes the synergistic response network of carbon metabolism and photosynthesis under salt stress.
基金support from the National Key Technology R&D Program of China(2021YFB3500801,2022YFC3901503,2022YFB3504302)the Natural Science Foundation and Overseas Talent Projects of Jiangxi Province(20232BAB214025,20232BCJ25044).
文摘Balancing electron transfer and intermediate adsorption ability of bifunctional catalysts via tailoring electronic structures is crucial for green hydrogen production,while it still remains challenging due to lacking efficient strategies.Herein,one efficient and universal strategy is developed to greatly regulate electronic structures of the metallic Ni-Fe-P catalysts via in-situ introducing the rare earth(RE)atoms(Ni-Fe-RE-P,RE=La,Ce,Pr,and Nd).Accordingly,the as-prepared optimal Ni-Fe-Ce-P/CC self-supported bifunctional electrodes exhibited superior electrocatalytic activity and excellent stability with the low overpotentials of 247 and 331 mV at 100 mA cm^(-2) for HER and OER,respectively.In the assembled electrolyzer,the Ni-Fe-Ce-P/CC as bifunctional electrodes displayed low operation potential of 1.49 V to achieve a current density of 10 mA cm^(-2),and the catalytic performance can be maintained for 100 h.Experimental results combined with density functional theory(DFT)calculation reveal that Ce doping leads to electron decentralization and crystal structure distortion,which can tailor the band structures and d-band center of Ni-Fe-P,further increasing conductivity and optimizing intermediate adsorption energy.Our work not only proposes a valuable strategy to regulate the electron transfer and intermediate adsorption of electrocatalysts via RE atoms doping,but also provides a deep under-standing of regulation mechanism of metallic electrocatalysts for enhanced water splitting.
基金financially supported by the National Natural Science Foundation of China(Nos.U20A20272 and52074073)the Fundamental Research Funds for the Central Universities(No.2325035)。
文摘To investigate the dissolution behaviors of Al_(2)O_(3)inclusions in CaO-5wt%MgO-SiO_(2)-30wt%Al_(2)O_(3)-TiO_(2)system ladle slags,confocal scanning laser microscopy was conducted on the slags with different TiO_(2)contents(0-10wt%),and scanning electron microscopy was performed to study the interfacial reaction between Al_(2)O_(3)and this slag system.The results disclose that the dissolution of Al_(2)O_(3)inclusions does not result in the formation of new phases at the boundary between the slag and the inclusions.In TiO_(2)-bearing and TiO_(2)-free ladle slags,there is no difference in the dissolution mechanism of Al_(2)O_(3)inclusions at steelmaking temperatures.Boundary layer diffusion is found as the controlling step of the dissolution of Al_(2)O_(3),and the diffusion coefficient is in the range of 4.18×10^(-10)to 2.18×10^(-9)m^(2)/s at 1450-1500℃.Compared with the solubility of Al_(2)O_(3)in the slags,slag viscosity and temperature play a more profound role in the dissolution of Al_(2)O_(3)inclusions.A lower viscosity and a lower melting point of the slags are beneficial for the dissolution.Suitable addition of TiO_(2)(e.g.,5wt%)in ladle slags can enhance the dissolution of Al_(2)O_(3)inclusions because of the low viscosity and melting point of the slags,while excessive addition of TiO_(2)(e.g.,10wt%)shows the opposite trend.
文摘Based on low-altitude remote sensing images,this paper established sample set of typical river vegetation elements and proposed river vegetation extraction technical solution to adaptively extract typical vegetation elements of river basins.The main research of this paper were as follows:(1)a typical vegetation extraction sample set based on low-altitude remote sensing images was established.(2)A low-altitude remote sensing image vegetation extraction model based on the focus perception module was designed to realize the end-to-end automatic extraction of different types of vegetation areas of low-altitude remote sensing images to fully learn the spectral spatial texture information and deep semantic information of the images.(3)By comparison with the baseline method,baseline method with embedded focus perception module showed an improvement in the precision by 7.37%and mIoU by 49.49%.Through visual interpretation and quantitative calculation analysis,the typical river vegetation adaptive extraction network has effectiveness and generalization ability,consistent with the needs of practical applications of vegetation extraction.
文摘短串联重复序列(short tandem repeat,STR)已广泛用于法医学亲子鉴定和个体识别中,但STR的突变可能会影响其结果的解释。在大多数类似研究中,由于忽略“隐性”突变现象,STR的突变率被低估。鉴于此,为获得更加准确的STR实际突变率,本研究使用Slooten与Ricciardi提出的有限突变模型和大规模数据,对28,313例(78,739个体)中国北京汉族已确认亲生关系的亲子鉴定案的20个常染色体STR基因座(D3S1358、D1S1656、D13S317、Penta E、D16S539、D18S51、D2S1338、CSF1PO、Penta D、TH01、vWA、D21S11、D6S1043、D7S820、D5S818、TPOX、D8S1179、D12S391、D19S433和FGA;由于有限突变模型中未包含D6S1043的矫正参数,因此本文实际计算其余19个STR基因座的突变率)进行了调查。结果发现,所有基因座均存在突变现象,总计发生1665个突变事件,包括1614个一步突变,34个两步突变,8个三步突变和9个非整步突变。基因座特异性的平均实际突变率在三联体中为0.00007700(TPOX)~0.00459050(FGA),在二联体中为0.00000000(TPOX)~0.00344850(FGA)。此外,本研究还分析了表面和实际突变率、三联体和二联体突变率、父源和母源的突变率之间的关系。研究表明,实际突变率多大于表面突变率,而且μ1^(*)/μ2^(*)(表面突变率)的比值通常也大于μ1/μ2(实际突变率)(μ1^(*),μ1;μ2^(*),μ2分别是一步和两步的突变率),即更多的“隐性”突变被释放出来。而且父源和母源的三联体和二联体的突变率也有存在差异。随后,将这些突变率数据与已发表的中国其他汉族人口的相关研究进行比较,展现出了STR突变率的时间与区域差异。由于样本量大,本研究中还报告了一些少见的突变事件,例如同卵双胞胎突变和“假四步突变”等。综上所述,本研究通过大量数据获得了接近真实的STR突变率的估计值,不仅可为中国法医DNA数据库和群体遗传学数据库提供重要的基础数据,也对开展法医学个体识别、亲权鉴定和遗传学研究具有重要的意义。
文摘Based on the investigation of long-life asphalt pavement at home and abroad,the development of long-life asphalt pavement technology in Shandong Province,China is reviewed in this paper.The structural combination char-acteristics of typical long-life asphalt pavement in Shandong Province and their popularization and application are introduced.The application effect of combined base long-life asphalt pavement,which has been widely promoted,is evaluated.At the same time,taking the Binda perpetual pavement test road in Shandong Province as an example,the dynamic response and long-term performance evolution of long-life asphalt pavement are analyzed over a period of more than 17 years.Sections S1,S2,and S3 present information about full-depth asphalt pavement.Section S4 describes combined base asphalt pavement.The results show that the maximum strain of S1–S4 is within the endurance strain limit.S1,S2,S3 and S4 are all expected to be long-life asphalt pavements.In the current study,Sections S1–S4 were maintained in good condition during a service period of more than 17 years with no structural cracks and good deflection,rutting,and IRI indexes.The deflection index was stable without growth,and the IRI was also relatively stable following the opening to traffic.The rutting depth un-derwent a slight cumulative increase within 8 years of opening,and then stabilized.The average rutting depth over the 17-year period was less than 15 mm.Therefore,S1–S4 meet the design standards required for use as long-life pavements.From the perspectives of resource saving,energy saving,and emission reduction and service performance,full-depth asphalt pavement can be considered to represent a new generation of green and durable pavement structures with great future promotion potential.
基金the National Natural Science Foundation of China(81473547,81673829).
文摘Objective:To systematically evaluate the clinical efficacy and safety of Qingkailing (QKL) injection for pediatric acute upper respiratory infection (AURI).Methods:We searched for randomized controlled trials (RCTs) of pediatric AURI treated by QKL and western medicine (WM) in the China National Knowledge Infrastructure Database,China Science and Technology Journal Database,Wanfang,Chinese Biomedical Literature Database,PubMed and Cochrane Library from inception to August,2016.Two reviewers independently retrieved the RCTs and extracted information.The Cochrane Collaboration Risk of Bias Assessment Tool was used to evaluate the methodological quality of RCTs.The data were meta-analyzed by RevMan 5.3 software.Results:Ultimately,21 RCTs that involved 2364 participants were included,and the quality of RCTs was generally poor.According to the meta-analysis,the combined use of QKL and WM for treating AURI can be effective,with a higher total effective rate,less defervescence time and less recovery time of tonsil and throat inflammation.Twenty-five adverse drug reactions (ADRs) were reported in three RCTs,but there were no serious ADRs.Conclusion:The combination of QKL and WM for treating pediatric AURI can result in better effects,but no definitive conclusions can be made regarding its safety.More rigorous RCTs are needed to support the clinical application of QKL.
基金National Natural Science Foundation of China(No.21972015)Young Top Talents Pro-ject of Liaoning Province(No.XLYC1907147)+2 种基金Joint Research Fund Liaoning-Shenyang National Laboratory for Materials Science(No.2019JH3/30100003)the Fundamental Research Funds for the Central Universities(No.DUT20TD06)the Swedish Research Council,and the K&A Wallenberg Foundation.
文摘Solar-driven water splitting is a promising alternative to industrial hydrogen production.This study reports an elaborate design and synthesis of the integration of cadmium sulfi de(CdS)quantum dots and cuprous sulfi de(Cu_(2)S)nanosheets as three-dimensional(3D)hollow octahedral Cu_(2)S/CdS p-n heterostructured architectures by a versatile template and one-pot sulfi dation strategy.3D hierarchical hollow nanostructures can strengthen multiple refl ections of solar light and provide a large specifi c surface area and abundant reaction sites for photocatalytic water splitting.Owing to the construction of the p-n heterostructure as an ideal catalytic model with highly matched band alignment at Cu_(2)S/CdS interfaces,the emerging internal electric fi eld can facilitate the space separation and transfer of photoexcited charges between CdS and Cu_(2)S and also enhance charge dynamics and prolong charge lifetimes.Notably,the unique hollow Cu_(2)S/CdS architectures deliver a largely enhanced visible-light-driven hydrogen generation rate of 4.76 mmol/(g·h),which is nearly 8.5 and 476 times larger than that of pristine CdS and Cu_(2)S catalysts,respectively.This work not only paves the way for the rational design and fabrication of hollow photocatalysts but also clarifi es the crucial role of unique heterostructure in photocatalysis for solar energy conversion.
基金the National Natural Science Foundation of China(Grant Nos.32002054,31930098,and 31801857)he National Key R&D of China(Grant No.2016YFD0100204-17)+2 种基金the Science and Technology Support Program of Hebei(Grant No.360108)the Natural Science Foundation of Hebei(Grant No.C2020204122)the International Cooperation Project in the Science and Technology Support Program of Hebei(Grant Nos.2019YX023A and 17396315D)。
文摘The agricultural and consumer quality of Chinese cabbage is determined by its shape.The shape is defined by the folding of the heading leaves,which defines the head top shape(HTS).The overlapping HTS,in which the heading leaves curve inward and overlap at the top,is the shape preferred by consumers.To understand the genetic regulation of HTS,we generated a large segregating F 2 population from a cross between pak choi and Chinese cabbage,with phenotypes ranging from nonheading to heading with either outward curving or inward curving overlapping heading leaves.HTS was correlated with plant height,outer/rosette leaf length,and petiole length.A high-density genetic map was constructed.Quantitative trait locus(QTL)analysis resulted in the identification of 22 QTLs for leafy head-related traits,which included five HTS QTLs.Bulked segregant analysis(BSA)was used to confirm HTS QTLs and identify candidate genes based on informative single-nucleotide polymorphisms.Interestingly,the HTS QTLs colocalized with QTLs for plant height,outer/rosette leaf,and petiole length,consistent with the observed phenotypic correlations.Combined QTL analysis and BSA laid a foundation for molecular marker-assisted breeding of Chinese cabbage HTS and directions for further research on the genetic regulation of this trait.
基金supported by the fundings from the National Natural Science Foundation of China (31930098,32172594)Hebei Provincial Department of Human Resources and Social Security (C20210363)+1 种基金Hebei Provincial Department of Science and Technology (216Z2904G)the Natural Science Foundation of Heibei (C2020204111).
文摘With the complementation of whole-genome sequencing of Chinese cabbage,it is necessary to develop genome-wide Simple Sequence Repeat(SSR)markers and analyse their characteristics,which will bring a revolution in the molecular marker-assisted breeding of Chinese cabbage.In this study distribution and characteristics of SSR loci in the genome of Chinese cabbage'Chiifu'was analyzed.Finally,a total of 173,892 SSR markers that occurred in 10 chromosomes were identified,and Perfect Repeat Motifs(P type)which is a main form of SSR loci with a mean distance of 1.89 kb/SSR was identified.Among them,mono-,di-,and tri-nucleotide repeat motifs were equally distributed across chromosomes compared with tetra-,penta-,and hexa-nucleotide repeat motifs.The largest proportion of SSR loci consisted of mono-and dinucleotide repeat motifs,which accounted for 93.04%of the total SSR loci.A/T and AT/TA were the most abundant motifs,accounting for 97.61%and 64.05%of the mono-and dinucleotide repeats,respectively.Furthermore,200 SSR markers were used for the amplification of 12 Chinese cabbage germplasm,in which 30 were highly polymorphic.These SSR markers were further used for the association analyses of flowering time of 190 Chinese cabbage accessions.The results revealed that 9 and 10 alleles were associated with bolting and flowering time,respectivley.The results show that development of SSR markers is feasible and useful in marker assisted selection of Chinese cabbage.
基金funded by the National Key R&D Program of China(2021YFE0101900)the Key R&D Program of Hebei,China(21327507D)the National Natural Science Foundation of China(32002138,T2222016,31972517)。
文摘Although China has achieved great advancements toward national food security,the country is still confronted with a range of challenges,including natural resource stress,imbalanced diets and environmental pollution.Optimized management of crop–livestock systems is the key measure to realize agricultural green transformation.However,optimized management of crop–livestock systems that use multi-objective zoning is lacking.This study employed a multi-objective zoning management approach to comprehensively analyze four indicators:ammonia volatilization,nitrogen surplus,soil carrying capacity and ecological red line area.With its significant ecological integrity and a strong emphasis on sustainability,the Baiyangdian Basin serves as a unique and suitable test case for conducting analyses on multi-objective nutrient optimization management,with the aim to facilitate the agricultural green transformation.This study finds that less than 8%of the area in the Baiyangdian Basin meet the acceptable environmental indicator standard,whereas around 50%of the area that had both nitrogen surplus and ammonia volatilization exceeded the threshold.Implementation of unified management,that is,the same management technique across the study areas,could result in an increase of areas meeting environmental indicator thresholds to 21.1%.This project developed a novel multi-indicator partition optimization method,in which distinct measures are tailored for different areas to satisfy multiple environmental indicators.Implementation of this method,could potentially bring more than 50%area below the threshold,and areas with ammonia emissions and nitrogen surplus could be reduced to 15.8%.The multi-indicators partition optimization method represents a more advanced and efficiency-oriented management approach when compared to unified management.This approach could be regarded as the best available option to help China achieve agricultural transformation to improve efficient production and reduce environmental pollution.It is recommended that current policies aimed at nutrient management toward sustainable agricultural development should shift toward the application of multi-indicators partition optimization.
文摘A recent UN Sustainable Development Goals(SDGs) analysis indicated a significant regression in the global SDG goal scores, particularly in SDG 2—Zero Hunger. The emissions of environmental pollution caused by meeting food demands have prompted some countries to intensify their climate change mitigation efforts. These circumstances have introduced significant uncertainty to the future global sustainable food development. Additionally, a notable global challenge is the persistence of hidden hunger, primarily characterized by the insufficient consumption of high-quality animal protein. Addressing this issue would necessitate increased environmental costs to attain high-quality food security. The future food system presents a significant challenge in coordinating food security, food quality and environmental quality. This article presents a comprehensive review and proposes a three-step strategy for future agricultural development based on food security, quality, and environmental aspects. This is a novel food system transfer strategy, as it concurrently addresses both global food security and environmental thresholds. It involves the construction of an efficient food system that operates within the constraints of environmental limits. The objective is to align with global SDG indicators and to maintain natural resource consumption and pollutant emissions within planetary boundaries.
基金financial support from the National Natural Science Foundation of China(No.22105061)Henan University start-up funding.
文摘Perovskite light-emitting diodes(PeLEDs)rely on optimized device architecture to realize effective electro-optical converting.Especially,the stacks of dissimilar semiconducting materials form heterointerfaces,at which the defects and energetics of perovskite film greatly affect the device performance.Herein,we focus on the heterointerface engineering of perovskite towards high-quality PeLEDs.The defect engineering at both the bottom-surface(namely buried interface)and top-surface of perovskite film is simultaneously performed by semiconducting passivating molecules,which feature aligned energy levels and superior carrier injection ability regarding to perovskite.Moreover,such defect passivation could influence the heterointerface energetics.The perovskite work function is decreased by our suggested passivator treatment because of interface dipole,which results in band bending at the heterojunction and modulates the carrier dynamics.Hence,the electron injection is greatly enhanced,which boosts the up-conversion electroluminescence in current system.Overall,via the heterointerface engineering of defects and energetics synergistically,efficient PeLEDs with 3-fold enhancement of external quantum efficiency and low driving voltages with respect to pristine ones are achieved based on our proposed PeLED architecture.
基金All participants who contributed to the survey from the Centers for Disease Control and Prevention(CDC),hospitals,and health facilities.
文摘Summary What is already known about this topic?Tuberculosis(TB)is often referred to as“a disease of poverty,”yet the information regarding the financial burden of TB care is limited and regionally representative.What is added by this report?This manuscript reported the national representative total and breakdown costs associated with TB care in China.The total cost per patient was 1,185 USD,of which 88%was direct cost and 37%was incurred prior to TB treatment.
文摘The performance of perovskite light-emitting diodes(PeLEDs)has been drastically improved recently.Therein,the coexistence of polydisperse perovskite domains has been one worthy subject of study.The crystallization of perovskite is affected by the buried interface character with the bottom contact layer;and the trap states also inherently exist at the buried interface of the perovskite film,which induce the nonradiative recombination and impede the PeLED performance.In this work,we focus on the crystallization modulation of monodisperse perovskite nanodomains toward high-performance PeLEDs.We show that a LiBr pre-modification layer on the bottom substrate induces the formation of monodisperse perovskite phase.In this system,the carrier transferring process deriving from the polydisperse phases is reduced.In addition,the LiBr pre-modification layer at the buried interface minimizes the trap states and enhances the radiative recombination of perovskites.Accordingly,our PeLEDs show a champion external quantum efficiency(EQE)of 25.5%for 4 mm2 device,and 22.9%for 100 mm^(2)device.