Twenty years of ocean observations with China Argo

The international Argo program,a global observational array of nearly 4000 autonomous profiling floats initiated in the late 1990s,which measures the water temperature and salinity of the upper 2000 m of the global ocean,has revolutionized oceanography.It has been recognized one of the most successful ocean observation systems in the world.Today,the proposed decade action“OneArgo”for building an integrated global,full-depth,and multidisciplinary ocean observing array for beyond 2020 has been endorsed.In the past two decades since 2002,with more than 500 Argo deployments and 80 operational floats currently,China has become an important partner of the Argo program.Two DACs have been established to process the data reported from all Chinese floats and deliver these data to the GDACs in real time,adhering to the unified quality control procedures proposed by the Argo Data Management Team.Several Argo products have been developed and released,allowing accurate estimations of global ocean warming,sea level change and the hydrological cycle,at interannual to decadal scales.In addition,Deep and BGC-Argo floats have been deployed,and time series observations from these floats have proven to be extremely useful,particularly in the analysis of synoptic-scale to decadal-scale dynamics.The future aim of China Argo is to build and maintain a regional Argo fleet comprising approximately 400 floats in the northwestern Pacific,South China Sea,and Indian Ocean,accounting for 9%of the global fleet,in addition to maintaining 300 Deep Argo floats in the global ocean(25%of the global Deep Argo fleet).A regional BGC-Argo array in the western Pacific also needs to be established and maintained.

Transition metal embedded in nonmetal-doped T-carbon [110]: A superior synergistic trifunctional electrocatalyst for HER, OER and ORR

The design of efficient and low-cost multifunctional electrocatalysts for hydrogen evolution reaction(HER), oxygen evolution reaction(OER) and oxygen reduction reaction(ORR) is critical for the development of clean energy. Two-dimensional(2D) carbon-based nano-materials are becoming more and more popular in heterogeneous catalysis due to their cost-effective and multi-scale tunability as single-atom catalysis(SACs) substrates. In this paper, by using first-principles calculation, we designed and demonstrated a novel macropore T-carbon [110](TC) monolayer as 2D electrocatalyst substrate for HER/OER/ORR, and the synergistic modification of the transition metal and nonmetal atoms(TM-X) were investigated to enhance the multifunctional electrocatalytic performance. We screened out the Co embedded in N-doped TC(Co3@N-TC) from 30 TM@X-TC monolayers as a trifunctional electrocatalysts, which exhibits superior performance for HER/ORR/OER on both thermodynamic and kinetic scales, and with excellent thermal and electrochemical stability. Then, the TC monolayer is naturally macropore with a diameter of 5.36 A and exhibits excellent adsorption capacity for the intermediates and products of the redox reactions. Moreover, we revealed the origin of the electrocatalytic activity using the crystal orbital Hamilton population(COHP) and the molecular orbitals(MOs). The d orbital of Co3@N-TC is significantly hybridized with the p orbital of the intermediates, so that the lone electrons initially occupied in the antibonding state pair up and occupy the downward bonding state, allowing *OH to be appropriately adsorbed onto the TC monolayer. This work not only demonstrates that the TM@X-TC monolayer is a superior synergistic trifunctional electrocatalyst, but also reveals a macropore monolayer material with potential applications in electrocatalysis.

Comparative transcriptome analysis of different heat stress responses between self-root grafting line and heterogeneous grafting line in rose

Rose is sensitive to high temperature which will make the rose go into a semi-dormancy state.Grafting is an excellent way to enhance rose heat tolerance.Here,heat-tolerant Rosa multiflora‘Huanong Wuci 1'(W)and heat-sensitive Rosa chinensis‘Old Blush’(X)were selected as experimental materials.The RNA-seq technique was used to investigate the transcriptomes of self-root grafting line(XX0),heterogeneous grafting line(XW0),self-root grafting line under 6 h heat stress(XX6),and heterogeneous grafting line under 6 h heat stress(XW6).Under high temperature stress,multiple signaling pathways were activated,moreover,a large number of transcription factors and functional genes were induced,especially the HSFs and HSPs with remarkably upregulated expression levels.The GO analysis showed that the differences in the expressions of the genes related to fatty acids and carbohydrates were observed between self-root grafting line and heterogeneous grafting line.In addition,14 P450s were differentially expressed,and one lectin gene was up-regulated in XW0 vs XW6,but down-regulated in XX0 vs XX6.Considering physiological and biochemical traits such as relative electrolyte leakage,SOD activity,proline,and total soluble sugars,DEGs involved in these processes may be key factors to resist high temperature.The present study provides an insight into the complex mechanism underlying grafting in response to heat stress.Our results indicate that grafting is an effective way to improve rose heat resistance.

Expression of Pseudorabies Virus gE Core Epitopes in Escherichia coli Strain BL21 and Utilization of Indirect PRV gE-ELISA

Pseudorabies virus glycoprotein E( PRV gE) has been recognized as a suitable diagnostic antigen for pseudorabies. In order to produce gE antigen in large quantities and at low cost,a gene fragment encoding PRV gE core epitopes was expressed in E. coli BL21 expression system. SDS-PAGE and Western Blotting revealed that the expression product in culture supernatant of E. coli BL21 was a recombinant protein,approximately 51. 8 Kd. At 5 h post-induction,protein concentration assay showed that the expression product amounted to 1. 65 mg /ml,accounting for 24. 17% of total proteins in the culture supernatant. An indirect PRV gE-ELISA was established by using the recombinant expression product as a coating antigen. Cross-reactivity assay showed that this antigen was PRV specific. In addition,the assay was consistently reproducible. Comparison of detection results of 240 serum samples between PRV gE-ELISA and a commercially available PRV diagnostic kit showed that there was no significant difference between these two methods( P > 0. 05).

CRISPR/Cas9 technology and its application in horticultural crops

Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR associated 9(CRISPR/Cas9)system has recently become one popular technology due to its efficiency,precision,and simplicity compared with other genome editing tools such as Zinc Finger Nucleases(ZFNs)and Transcription Activator Like Effector Nucleases(TALENs).Horticultural crops provide energy and health-keeping nutrients to humankind.Genome-editing technology has become widely adopted in horticultural breeding with the increasing demand for high yield and better-quality horticultural crops.Here,we describe the CRISPR/Cas9 system construction,its optimization,including sgRNA promoter,sgRNA design,Cas9 protein promoter,SpCas9 variants and orthologs,and vector delivery methods.We also summarized the application of this technology in horticultural plants for stress responses enhancement,fruit quality improvement,and cultivation traits modification.This detailed review was compiled to help establish comprehensive understanding of the CRISPR/Cas9 systems and provide a reference for further developing this technology to manipulate horticultural plant traits effectively.

Antithrombin gene Arg197Stop mutation-associated venous sinus thrombosis in a Chinese family

This study sought to elucidate the genetic correlation of cerebral venous sinus thrombosis caused by a hereditary antithrombin deficiency in a Chinese family,at the genetic and protein levels.A nonsense mutation from C to T on locus 6431 in exon 3B of the antithrombin gene was observed,leading to an arginine (CGA) to stop codon (TGA) change in the protein.This is the first report of this mutation in China.Ineffective heparin therapy in the propositus patient is associated with a lack of heparin binding sites after antithrombin gene mutation.Characteristic low intracranial pressure in the acute phase might be specific to this patient with cerebral venous sinus thrombosis.

Fishery analysis using gradient-dependent optimal interpolation

The current lack of high-precision information on subsurface seawater is a constraint in fishery research.Based on Argo temperature and salinity profiles,this study applied the gradient-dependent optimal interpolation to reconstruct daily subsurface oceanic environmental information according to fishery dates and locations.The relationship between subsurface information and matching yellowfin tuna(YFT)in the western and central Pacific Ocean(WCPO)was examined using catch data from January 1,2008 to August 31,2017.The seawater temperature and salinity results showed differences of less than±0.5°C and±0.01 compared with the truth observations respectively.Statistical analysis revealed that the most suitable temperature for YFT fishery was 28–29°C at the near-surface.The most suitable salinity range for YFT fishery was 34.5–36.0 at depths shallower than 300 m.The suitable upper and lower bounds on the depths of the thermocline were 90–100 m and 300–350 m,respectively.The thermocline characteristics were prominent,with a mean temperature gradient exceeding 0.08°C/m.These results indicate that the profiles constructed by gradient-dependent optimal interpolation were more accurate than those of the nearest profiles adopted.

Thermocline Model for Estimating Argo Sea Surface Temperature Thermocline Model for Estimating Argo Sea Surface Temperature

Argo has become an important constituent of the global ocean observation system.However,due to the lack of sea surface measurements from most Argo profiles,the application of Argo data is still limited.In this study,a thermocline model was constructed based on three key thermocline parameters,i.e,thermocline upper depth,the thermocline bottom depth,and thermocline temperature gradient.Following the model,we estimated the sea surface temperature of Argo profiles by providing the relationship between sea surface and subsurface temperature.We tested the effectiveness of our proposed model using statistical analysis and by comparing the sea surface temperature with the results obtained from traditional methods and in situ observations in the Pacific Ocean.The root mean square errors of results obtained from thermocline model were found to be significantly reduced compared to the extrapolation results and satellite retrieved temperature results.The correlation coefficient between the estimation result and in situ observation was 0.967.Argo surface temperature,estimated by the thermocline model,has been theoretically proved to be reliable.Thus,our model generates theoretically feasible data present the mesoscale phenomenon in more detail.Overall,this study compensates for the lack surface observation of Argo,and provides a new tool to establish complete Argo data sets.

Healing Effect and Underlying Mechanism of Silver Nanoparticles Prepared Using Carboxymethyl Chitosan under Solar Irradiation

In our previous study,silver nanoparticles were prepared using AgNO_(3) and carboxymethyl chitosan(CMCS)which is commercially available with solar irradiation.In this study,the efficacy and safety of silver nanoparticles prepared by this method were evaluated for healing wounds in rats with diabetes.We also attempted to determine the underlying mechanism and influencing factors of the silver nanomaterial preparation method.Compared with growth factors,silver nanoparticles exhibit better healing effects for rats with diabetes.No remnant silver ions were detected in the major organs of these rats after the application of silver nanoparticles.Silver nanoparticles prepared using CMCS are less toxic than those prepared from the conventional method,promote the proliferation of skin fibroblasts,and are promising as a topical medication for infected wounds.An obvious breakage process of the particles is observed during the growth of nanocrystalline silver in CMCS.In this study,we also attempted to determine whether this method is suitable for synthesizing silver nanoparticles using N-trimethyl chitosan chloride and sodium alginate were used in this particular experiment.The characteristic UV-vis absorbance peak of silver nanoparticles was found only in the reaction mixture containing N-trimethyl chitosan chloride.Our study demonstrates that free radicals are the key factor in this silver nanoparticle preparation method.

择期颈椎手术患者围术期发生主要不良心脏事件的影响因素

目的探讨择期颈椎手术患者围术期发生主要不良心脏事件(major adverse cardiac events,MACE)的影响因素。方法回顾性分析河北北方学院附属第一医院2017年3月至2021年3月收治的426例行择期颈椎手术患者的临床资料。收集患者的基本信息,包括性别、年龄、体质量指数(body mass index,BMI)、基础疾病,并根据基础疾病计算Charlson合并症指数(Charlson comorbidity index,CCI),收集术前血清肌钙蛋白I(cardiac troponin I,cTnI)水平和围术期MACE发生情况以及手术相关指标,包括颈椎手术类型、手术方式、入路方式、手术时间、麻醉时间、术中出血量、术后疼痛视觉模拟量表(visual analogue scale,VAS)评分、电解质紊乱情况。计数资料以例(%)表示,组间比较采用χ^(2)检验;应用Logistic回归模型对颈椎手术患者围术期发生MACE的影响因素进行多因素分析。结果426例患者中围术期发生MACE 54例(12.68%),其中不稳定型心绞痛4例(7.41%)、急性心肌梗死4例(7.41%)、严重心律失常33例(61.11%)、急性心力衰竭13例(24.07%)。多因素Logistic回归分析结果显示,年龄增加(50~59岁:比值比=1.34,95%置信区间:1.14~1.78;60~69岁:比值比=1.48,95%置信区间:1.20~1.86;70~79岁:比值比=1.71,95%置信区间:1.34~2.57;80~89岁:比值比=1.95,95%置信区间:1.46~2.85)以及女性、CCI评分>3分、术前cTnI>0.04μg/L、术后VAS评分>5分和电解质紊乱均为颈椎手术患者围术期发生MACE的影响因素(比值比分别为1.84、2.12、2.34、2.57、2.20,95%置信区间分别为1.34~2.68、1.50~3.41、1.63~3.72、1.53~4.01、1.43~3.69,均P<0.05)。结论择期颈椎手术患者围术期MACE的发生率较高,年龄增加、女性、高CCI评分、术前血清cTnI水平较高、术后疼痛和电解质紊乱均为择期颈椎手术患者围术期MACE发生的影响因素。

万寿菊再生体系的建立及优化

以40个不同基因型万寿菊(Tagetes erecta)叶片为外植体,在相同条件下诱导不定芽分化,获得最佳再生基因型;然后分析不同激素组合、外植体切口方式、固化剂及蔗糖对万寿菊再生和玻璃化影响;最后对不同类型的伸长培养基进行探索。结果表明,最佳再生基因型为里程碑·黄色;最佳再生培养基为MS+0.2 mg·L^(-1)TDZ+0.5 mg·L^(-1)IBA+8 g·L^(-1)琼脂+40g·L^(-1)蔗糖,再生率达70%,玻璃化率降低至16%;最适再生的小叶部位为全小叶;最适伸长培养基为MS+8 g·L^(-1)琼脂+30g·L^(-1)蔗糖,伸长率达91.3%。该研究建立了高效稳定的万寿菊再生体系,解决了万寿菊再生过程中严重的玻璃化问题,可为万寿菊的遗传改良和基因功能研究奠定基础。

Naringenin reduces lung metastasis in a breast cancer resection model

Metastasis is the main cause of death in cancer patients. To improve the outcomes of patients undergoing a surgery, new adjuvant therapies that can effectively inhibit metastases have to be developed. Studies have shown that flavonoid naringenin, a natural product that is mainly present in grapes and citrus, may contribute to cancer prevention. It has many advantages compared to traditional chemotherapeutic drugs, such as low toxicity. To determine whether naringenin can also inhibit metastases, a breast cancer resection model that mimics clinical situations was established. We found that orally administered naringenin significantly decreased the number of metastatic tumor cells in the lung and extended the life span of tumor resected mice. Flow cytometry analysis revealed that T cells displayed enhanced antitumor activity in naringenin treated mice, with an increased proportion of IFN-γ and IL-2 expressing T cells. In vitro studies further demonstrated that relief of immunosuppression caused by regulatory T cells might be the fundamental mechanism of metastasis inhibition by naringenin. These results indicate that orally administered naringenin can inhibit the outgrowth of metastases after surgery via regulating host immunity. Thus, naringenin can be an ideal surgical adjuvant therapy for breast cancer patients.

Chrysin promotes osteogenic differentiation via ERK/MAPK activation

T he effect of the anti-infl ammatory fl avonoid chrysin on osteogenesis was determined in preosteoblast MC3T3-E1 cells.Results demonstrated that chrysin could induce osteogenic differentiation in the absence of other osteo-genic agents.Chrysin treatment promoted the expres-sion of transcription factors(Runx2 and Osx)and bone formation marker genes(Col1A1,OCN,and OPN)as well as enhanced the formation of mineralized nodules.During osteogenic differentiation,chrysin preferentially activated ERK1/2,but not JNK nor the p38 MAPKs.Further experi-ments with inhibitors revealed the co-treatment of U0126,PD98059,or ICI182780(a general ER antagonist)with chrysin effectively abrogated the chrysin-induced osteo-genesis and ERK1/2 activation.Thus,the effect of chrysin on osteogenesis is ERK1/2-dependent and involves ER.Therefore,chrysin has the signifi cant potential to enhance osteogenesis for osteoporosis prevention and treatment.

Multi-objective optimization design of wheat centralized seed feeding device based on particle swarm optimization (PSO) algorithm

In order to solve the problem of interaction between multiple evaluation indexes of seed metering performance under multiple factors of centralized seed feeding device,a multi-objective optimization of structure based on particle swarm optimization(PSO)algorithm was proposed in this paper.The wheat centralized seed feeding device was taken as the research object,and the experimental factors were cone angle of type hole,working speed and seed filling gap.The working process of wheat centralized seed feeding device was simulated by discrete element method(DEM).The average seed number of type hole,the variation coefficient of the average seed number of type hole,and the maximum tangential force between seed and seed feeding mechanism were selected as the evaluation indexes.Through the variance analysis of the evaluation indexes by the experimental factors,the optimization objective function was constructed.Using PSO algorithm,the multi-objective optimization was carried out for the wheat centralized seed feeding device.The optimization results show that the best structural combination parameters of the wheat centralized seed feeding device are the hole cone angle of 31.6°and the seed filling gap of 4.6 mm.The validity of the method was verified by simulation and field test.The results show that the PSO algorithm multi-objective optimization method proposed in this paper can provide a reference for the structural improvement and optimal design of the centralized seed feeding device.

Effects of subsoiling on working quality and total power consumption of high stubble straw returning machine

Straw returning into field is a direct and effective measure to reduce the straw burning and improve the soil organic matter content.Straw returning directly to field needs higher performance machines,especially under the condition of large amount of straw in the field is more difficult.Therefore,the model of conservation tillage by combination of subsoiling and straw returning was studied.Experiments on combined tillage machine for effect of subsoiling on working quality and total power consumption for high stubble straw returning were carried out.The high stubble rape field was used as the test field;forward speed and PTO speed of tractor were taken as the test factors.Straw coverage rate and straw proportion of the lower half burying layer were taken as the test indexes of the working quality.Subsoiling and rotary burying(SRB)returning operation was used as experimental group and direct rotary burying(DRB)returning operation was the control group.The results showed that under different working conditions,the mean value of straw coverage rate of SRB was 93.0%,straw proportion of the lower half burying layer was 52.8%,these values were better than DRB.The straw proportion of the lower half burying layer of SRB compared with DRB increased by 10.5%.Two factors all had a significant effect on it under the SRB and DRB conditions.Subsoiling could significantly reduce the PTO torque.Under low speed,the total power consumption of SRB was slightly smaller,while under high speed,the total power consumption of DRB was slightly smaller.Under the SRB and DRB conditions,two factors both had a significant effect on total power consumption.The optimal working combination(working quality as the primary index)was 1.5 km/h of forward speed and 720 r/min of PTO speed.Under this condition,the straw coverage rate was 94.1%,the straw proportion of the lower half burying layer was 59.0%,and the total power consumption was 35.62 kW.The research confirmed that subsoiling is beneficial to the working quality and total power consumption of high stubble straw returning machine.It could meet the working requirements,and provide a reference for optimizing straw returning machine and improving working quality.

Femtosecond laser-induced periodic surface structures on lithium niobate crystal benefiting from sample heating

Periodic surface structures were fabricated by irradiating lithium niobate(LN) crystals with femtosecond laser pulses at sample temperatures ranging from 28℃ to 800℃. Carrier density and conductivity of the samples were increased via heating LN, which inhibited coulomb explosion to obtain a uniform periodic surface structure. The periodic surface structures cover an area of 8 mm × 8 mm and have an average spacing of 174 5 nm.Meanwhile, the absorption of the processed sample is about 70% in the spectral range of 400–1000 nm, which is one order of magnitude higher than that of pure LN. Fabrication of periodic surface structures on heating LN with femtosecond laser pulses provides a possibility to generate nanogratings or nanostructures on wide-bandgap transparent crystals.

Effects of blade sliding cutting angle and stem level on cutting energy of rice stems

Previous studies highlighted the significance of optimizing the cutting blade for crop harvesting and size reduction.This study investigated the effect of blade sliding cutting angle and stem level on cutting energy of single rice stem using a cutting apparatus that combined with texture analyzer.The cutting energy was determined for four blade angles.The results showed that the average cutting energy was the highest for cutting stem upper level and the lowest for cutting stem lower level.It was found that the peak cutting force per unit stem area decreased with blade sliding cutting angle increased.However,the least average cutting energy was 9.12 J/mm^(2) of 45°sliding angle when cutting without counter support blade and 32.3%less than that of 60°sliding angle.When cutting with counter support blade,the cutting energy per unit stem area varied from 6.57 to 12.54 J/mm 2 as the sliding angle varied from 0°to 60°,whereas the peak cutting force per unit stem area varied from 2.46 to 0.98 N/mm 2.It was concluded that the optimal sliding cutting angle was 45°without support blade and 30°with support blade,respectively.The experiments on rice stems in this study indicated that optimization of sliding cutting angle and stem level have a significant effect on cutting energy savings.Also this study emphasized the need to further investigate the effect of the case of more moisture content and cutting speed on the cutting energy to help in selection of optimum cutting speed and harvesting time.

Fabrication of nanostructure in inner-surface of AISI 304 stainless steel pipe with surface plastic deformation

In the present investigation, a pipe inner-surface grinding(PISG) technique was developed to fabricate nanostructure in the inner-surface of an austenitic 304 stainless steel pipe. PISG was performed by high speed shearing with hard sphere tips, leading to gradient distribution of strain, strain rate and strain gradient along depth. Nano-austenite with an average boundary spacing of 20 nm was generated, followed by deformation microstructure characterized by shear bands, multi-and uni-directional twins and planar dislocation arrays. Deformation induced grain refinement of austenitic 304 stainless steel with low stacking fault energy(SFE) covering 4–5 order's magnitude of length scales toward nanometer regime was unified.

On the microstructural evolution pattern toward nano-scale of an AISI 304 stainless steel during high strain rate surface deformation

In the present investigation,an austenitic AISI 304 stainless steel was subjected to high strain rate surface deformation by Pipe Inner-Surface Grinding(PISG)technique.The depth-dependent deformation parameters(strain,strain rate and strain gradient)were evaluated and the microstructures were systematically characterized.Microstructural evolution from millimeter-to nano-scale was explored,with special attention paid to the localized deformation.Microstructural evolution begins with the formation of planar dislocation arrays and the twin-matrix lamellae,which is followed by the localized deformation characterized by the initiation and the development of shear bands.A twinning-dominated process that was supplemented with dislocation slip-dominated one governed the microstructural evolution inside shear bands.The twin-matrix lamellae transform into extended/lamellar structure and finally the nanosized grains.Austenitic grains were substantially refined and martensitic transformation was effectively suppressed,of which the underlying mechanisms were analyzed.