Research on Three-Dimensional Simulation of the Internal Arc Gear Skiving

Aiming at the problems that the simulation accuracy which is reduced due to the simplification of the model,a three-dimensional simulation method based on solid modeling is being proposed.By analyzing the motion relationship and positional relationship between the caries knife and the workpiece,the coordinate system of the caries machining was established.With the MATLAB software,the cutting edge model and the blade sweeping surface model of the boring cutter are sequentially established.Boolean operation is performed on the blade swept surface formed by the tooth cutter teeth with time t and the workpiece tooth geometry as well as the undeformed three-dimensional chip geometry model and the instantaneous cogging geometry model are obtained at different times.Through the compare between gear end face simulation tooth profile and the theoretical inner arc tooth profile,we verified the accuracy and rationality of the proposed method.

Investigating the effect of the Tibetan Plateau on the ITCZ using a coupled Earth system model

本文利用耦合地球气候系统模式研究了青藏高原对热带辐合带(ITCZ)的影响.我们研究发现热带大西洋ITCZ的位置对青藏高原存在与否有明显的敏感性.与目前真实情况相比,移除青藏高原会导致北半球海面降温,南半球海面升温.这种海面温度变化在大西洋表现得尤为明显,导致热带大西洋最大海温中心向南移动,从而迫使大气对流中心向南移动,即表现为ITCZ的南移.相应地,夏季热带大气Hadley环流的上升支也发生明显南移.北(南)半球海洋变冷(变暖)这种态势要求增强跨赤道向北的大气经向热量输送,从而维持各个半球的能量平衡,而这需要ITCZ位置的南移才能实现.本文研究表明,青藏高原的存在在现今ITCZ气候态的形成中可能扮演了重要角色.

Understanding the Development of the 2018/19 Central Pacific El Niño

A central Pacific(CP)El Niño event occurred in 2018/19.Previous studies have shown that different mechanisms are responsible for different subtypes of CP El Niño events(CP-I El Niño and CP-II El Niño).By comparing the evolutions of surface winds,ocean temperatures,and heat budgets of the CP-I El Niño,CP-II El Niño,and 2018/19 El Niño,it is illustrated that the subtropical westerly anomalies in the North Pacific,which led to anomalous convergence of Ekman flow and surface warming in the central equatorial Pacific,played an important role in the 2018/19 El Niño event as well as in the CP-II El Niño.Although the off-equatorial forcing played a vital role,it is found that the equatorial forcing acted as a driving(damping)term in boreal spring(summer)of the 2018/19 El Niño.The 2018/19 El Niño provides a timely and vivid example that helps illustrate the proposed mechanism of the CP El Niño,which could be leveraged to improve El Niño predictability.

数字时代下文化产品贸易发展与增强中华文明全球影响力创新路径研究

在中华民族创造的人类文明新形态的形成发展过程中,中华优秀传统文化发挥着重要作用,是承载着中华价值观念、信仰和文化符号的文化产品,是一种传播中华文明的重要物质力量。党的二十大报告明确提出了“增强中华文明传播力影响力”的任务要求,数字经济时代,文化产品国际贸易中的交流和传播,在提升中华文明全球传播力影响力方面有着独特的功能和效应。本文立足数字化时代特点,关注新媒体环境下文化产业发展与中华文明国际传播的新趋势、新理念、新平台打造,探讨文化产品贸易发展与增强中华文明全球影响力的创新路径。

Characterization of 500 Chinese patients with cervical esophageal cancer by clinicopathological and treatment outcomes

Objective: There are no comprehensive studies on survival outcomes and optimal treatment protocols for cervical esophageal cancer(CEC), due to its rare clinical prevalence. Our objective was to determine the relationship between pathological characteristics, treatment protocols, and survival outcomes in Chinese CEC patients.Methods: A total of 500 Chinese CEC patients were selected from our 500,000 esophageal and gastric cardia carcinoma database(1973–2018). There were two main groups: patients treated with surgery, and patients receiving non-surgical treatments(radiotherapy, radiochemotherapy, and chemotherapy). The Chi-square test and Kaplan–Meier method were used to compare the continuous variables and survival.Results: Among the 500 CEC patients, 278(55.6%) were male, and the median age was 60.9 ± 9.4 years. A total of 496 patients(99.2%) were diagnosed with squamous cell carcinoma. In 171(34.2%) patients who received surgery, 22(12.9%) had undergone laryngectomy. In 322(64.4%) patients who received non-surgical treatments, 245(76.1%) received radiotherapy. Stratified survival analysis showed that only T stage was related with survival outcomes for CEC patients in the surgical group, and the outcomes between laryngectomy and non-laryngectomy patients were similar. It was noteworthy that the 5-year survival rate was similar in CEC patients among the different groups treated with surgery, radiotherapy, chemotherapy, or radiochemotherapy(P = 0.244). Conclusions: The CEC patients had similar survival outcomes after curative esophagectomy and radiotherapy, including those with or without total laryngectomy. These findings suggest that radiotherapy could be the initial choice for treatment of Chinese CEC patients.

Introduction to the special section:Recent advancement on integrated carbonate reservoirs prediction with complex secondary storage space

Carbonate reservoirs in Western China show tremendous exploration and development potential.These have become the key area for oil and gas reserves addition and sustainable resource development for China.Compared to conventional carbonate reservoirs,prediction of this kind of reservoir predominated by secondary storage is much more difficultand presents significant challenges.

Controlling the Coffee Ring Effect on Graphene and Polymer by Cations

Recently,there are great efforts that have been taken to suppressing/controlling the coffee ring effect,but it is of challenge to achieve inexpensive and efficient control with less disturbance,suitable for scalable production and highly enhancing the printing/dyeing color fastness.By only adding trace amounts of salt into the suspensions,here we experimentally achieve the facile and highly efficient control of the coffee ring effect of suspended matter on substrates of graphene,natural graphite,and polyethylene terephthalate surfaces.Notably,friction force measurements show that ion-controlled uniform patterns also greatly enhance color fastness.Molecular dynamics simulations reveal that,due to strong hydrated cation-π interactions between hydrated cations and aromatic rings in the substrate surface,the suspended matters are adsorbed on the surfaces mediated by cations so that the suspended matters are uniformly distributed.These findings will open new avenues for fabricating functional patterns on graphene substrates and will benefit practical applications including printing,coating,and dyeing.

Unexpectedly Strong Diamagnetism of Self-Assembled Aromatic Peptides

There is a considerable amount of work that shows the biomagnetism of organic components without ferromagnetic components at the molecular level,but it is of great challenge to cover the giant gap of biomagnetism between their experimental and theoretical results.Here we show that the diamagnetism of aromatic peptides is greatly enhanced for about 11 times by self-assembling,reaching two orders of magnitude higher than the mass susceptibility of pure water.The self-assembly of aromatic rings in the peptide molecules plays the key role in such a strong diamagnetism.

Genesis and Accumulation of Paleo-Oil Reservoir in Dabei Area,Kuqa Depression,Northwest China:Implications for Tight-Gas Accumulation

Paleo-oil reservoir is of great importance to understand hydrocarbon enrichment mechanism and hydrocarbon exploration potential,but is yet poorly investigated in Kuqa Depression.The occurrence of the paleo-oil reservoir in Dabei area was proved by quantitative grain fluorescence(QGF)and fluid inclusion petrography.Development history of the paleo-oil reservoir was reconstructed through:(1)oil-source correlation;(2)time coupling of source rock maturation,porosity evolution and migration pathways.The impact of paleo-oil reservoir on tight-gas accumulation was consequently discussed.Results suggest that considerable oil was accumulated in the K_(1)bs reservoir with paleo oil-water contact in Dabei 2 Well and Dabei 201 Well at 5800 and 6040 m,respectively.Crude oil was primarily sourced from Triassic source rocks with Jurassic source rocks of secondary importance,which was at oil generation window(0.7%–1.1%Ro)during 9–6 and 7.5–5 Ma,respectively.The occurrence of K_(1)bs tight reservoir(porosity<12%)was about 25 Ma,while faults and associated fractures at Kelasue structural belt were developed approximately from 8 to 3.5 Ma.Therefore,the tight oil accumulation was formed during 8–5 Ma.The paleo-oil reservoir in Dabei 1 gas field was destroyed by the evaporation fractionation in later stage.

An MA-MRR model for transaction-level analysis of highfrequency trading processes

The transaction-level analysis of security price changes by Madhavan,Richardson,and Roomans(1997,hereafter MRR)is a useful framework for financial analysis.The first-order Markov property of trading indicator variables is a critical assumption in the MRR model,which contradicts the information lag empirically demonstrated in high-frequency trading processes.In this study,a nonparametric test is employed,which shows that the Markov property of the trading indicator variables is rejected on most trading days.Based on the spread decomposed structure,an MA-MRR model was proposed with a moving average structure adopted to absorb the information lag as an extension.The empirical results show that the information lag plays an important role in measuring the adverse selection risk parameter and that the difference in this parameter between the original and the extension is significant.Furthermore,our analysis suggests that the information lag parameter is a useful measure of the average speed at which information is incorporated into prices.

多百年际气候变率:观测、理论与模拟研究

长时间序列的代用资料表明,地球气候系统存在着数百年时间尺度的气候变率.这种变率产生的原因及机制一直是困扰气候学家和考古学家的重大科学问题.从全新世中期直至工业革命之前,地球所受的外强迫变化较小,研究这一时期气候系统的长期自然振荡非常重要.本文从观测、理论和模拟研究3个方面对多百年际气候变率的研究现状进行了详细梳理.我们期望能够通过创新性的理论和模式试验方法,勾画多百年际气候变率的空间模态,解密其时间尺度来源,揭示其内在运行机理,取得原创性成果,回答海洋动力学和气候动力学的一些基础科学问题.

Photocatalytic direct oxygen-isotopic labelings of carbonyls in ketones and aldehydes with oxygen-isotopic waters

Oxygen-isotopic labelings play important roles in identifying and understanding chemical and biological processes.Direct C=O to C=^(18)O or C=^(17)O conversion in a single step leading to labeled compounds can alleviate synthetic burdens without the need for resynthesis.Here we describe a photocatalytic oxygenisotopic labeling protocol that can efficiently and selectively install ^(18)O and ^(17)O on carbonyls of ketones and aldehydes via oxygen isotope exchange with oxygen-isotopic waters(H_(2)^(18)O or H_(2)^(17)O)as the sources of oxygen isotopes,in which light and oxygen-enabled sodium alkanesulfinates catalyzed this process.This strategy was extended to the in-situ formed ketones from the photocatalytic aerobic oxidation of alkyl arenes and secondary alcohols.Furthermore,reduction of the oxygen-isotopically labeled aldehydes with NaBH_(4) provided the corresponding oxygen-isotopically labeled primary alcohols.We believe that the oxygen-isotopically labeling method will be widely used in chemistry,biology and medicine fields.

Interactive effects of water and nitrogen addition on soil microbial communities in a semiarid steppe

Aims Better understanding of microbial compositional and physiological acclimation mechanisms is critical for predicting terrestrial ecosystem responses to global change.The aim is to assess variations in soil microbial communities under future scenarios of changing precipitation and N deposition in a semiarid grassland of northern China.Methods In order to explicitly estimate microbial responses,a field experiment with water and N addition was established in April 2005 and continuously conducted for 4 years.Specifically,soil microbial community composition and microbial C utilization potential were determined by phospholipid fatty acid(PLFA)and community-level physiological profiles,respectively.Important Findings Water addition had no effects on the PLFA concentrations of grampositive(GP)and negative bacteria(GN),total bacteria and fungi.However,N addition caused significant reductions in the PLFA concentrations of GP,GN,total bacteria and fungi and thus decreased total PLFA of microbial communities.Moreover,there were interactive effects of water and N addition on GN/GPand the ratio of fungal to bacterial PLFA(F/B).In addition,synergistic effects were found between water and nitrogen in affecting microbial C utilization potentials,which implies that microbial C utilization potentials tend to be enhanced when both N and water availability are sufficient.Overall,the microbial responses to water and N addition support our hypothesis that water and N addition may be combined together to affect microbial communities in the semiarid grassland.

An individualized immune signature of pretreatment biopsies predicts pathological complete response to neoadjuvant chemoradiotherapy and outcomes in patients with esophageal squamous cell carcinoma

No clinically available biomarkers can predict pathological complete response(pCR)for esophageal squamous cell carcinomas(ESCCs)with neoadjuvant chemoradiotherapy(nCRT).Considering that antitumor immunity status is an important determinant for nCRT,we performed an integrative analysis of immune-related gene profiles from pretreatment biopsies and constructed the first individualized immune signature for pCR and outcome prediction of ESCCs through a multicenter analysis.During the discovery phase,14 differentially expressed immune-related genes(DEIGs)with greater than a twofold change between pCRs and less than pCRs(<pCRs)were revealed from 28 pretreatment tumors in a Guangzhou cohort using microarray data.Ten DEIGs were verified by qPCR from 30 cases in a Beijing discovery cohort.Then,a four-gene-based immune signature(SERPINE1,MMP12,PLAUR,and EPS8)was built based on the verified DEIGs from 71 cases in a Beijing training cohort,and achieved a high accuracy with an area under the receiver operating characteristic curve(AUC)of 0.970.The signature was further validated in an internal validation cohort and an integrated external cohort(Zhengzhou and Anyang cohorts)with AUCs of 0.890 and 0.859,respectively.Importantly,a multivariate analysis showed that the signature was the only independent predictor for pCR.In addition,patients with high predictive scores showed significantly longer overall and relapse-free survival across multiple centers(P<0.05).This is the first,validated,and clinically applicable individualized immune signature of pCR and outcome prediction for ESCCs with nCRT.Further prospective validation may facilitate the combination of nCRT and immunotherapy.

Phosphorus transformation under the influence of aluminum,organic carbon,and dissolved oxygen at the water-sediment interface:A simulative study

The effects of sediment aluminum(Al),organic carbon(OC),and dissolved oxygen(DO)on phosphorus(P)transformation,at the water-sediment interface of a eutrophic constructed lake,were investigated via a series of simulative experiments.The above three factors had various influences on dissolved P concentration,water pH,water and surface sediment appearance,and P fractions.Additions of Al had the greatest effect on suppressing P release,and the water p H remained alkaline in the water-sediment system under various OC and DO conditions.No dissolution of the added Al was detected.31P-N M R characterization suggested that OC addition did not promote biological P uptake to polyphosphates under oxic conditions.The simulation result on the added phytate indicated the absence of phytate in the original lake sediment.As compared to the reported natural lakes and wetland,the water-sediment system of the constructed lake responded differently to some simulative conditions.Since Al,OC,and DO can be controlled with engineering methods,the results of this study provide insights for the practical site restorations.

An Aqueous Asymmetric Supercapacitor Based on Activated Carbon and Tungsten Trioxide Nanowire Electrodes

An asymmetric supercapacitor （ASC） was assembled by using an activated carbon as positive electrode and WO3 nanowire as negative electrode, and its electrical performances were tested in voltage windows ranging from 0 to 1.5 V. A high specific capacitance of 51 Fog-1 could be achieved at the current density of 0.25 A·g-1 . Moreover, the ASC displays a good cycling stability with 86% of capacitance retention after 800 cycles, its energy density can be up to 11.9 Wh·kg-1 at the power density of 210 W·kg -1, and remains 7.7 Wh·kg-1 at a power density of 1250 W· kg-1. The excellent electrical performance is perhaps due to the crystal orientation of （001） planes for the WO3 nanowire, which favors the rapid reaction between W（VI） and H＋ cations. This aqueous asymmetric WO3//AC supercapacitor is promising for practical applications due to its easy preparation of WO3.

An Old Story Retold: Loss of G1 Control Defines A Distinct Genomic Subtype of Esophageal Squamous Cell Carcinoma

Esophageal squamous cell carcinoma （ESCC） has a high mortality rate. To determine the molecular basis of ESCC development, this study sought to identify characteristic genome-wide alterations in ESCC, including exonic mutations and structural alterations. The clinical implications of these genetic alterations were also analyzed. Exome sequencing and verification were performed for nine pairs of ESCC and the matched blood samples, followed by validation with additional sam- ples using Sanger sequencing. Whole-genomc SNP arrays were employed to detect copy number alteration （CNA） and loss of heterozygosity （LOH） in 55 cases, including the nine ESCC samples subjected to exome sequencing. A total of 108 non-synonymous somatic mutations （NSSMs） in 102 genes were verified in nine patients. The chromatin modification process was found to be enriched in our gene ontology （GO） analysis. Tumor genomes with TP53 mutations were signifi- cantly more unstable than those without TP53 mutations. In terms of the landscape of genomic alterations, deletion of 9p21.3 covering CDKN2A/2B （30.9%）, amplification of 1 1q13.3 covering CCND1 （30.9%）, and TP53 point mutation （50.9%） occurred in two-thirds of the cases. These results suggest that the deregulation of the G1 phase during the cell cycle is a key event in ESCC. Furthermore, six minimal common regions were found to be significantly altered in ESCC samples and three of them, 9p21.3, 7p 11.2, and 3p 12.1, were associated with lymph node metastasis. With the high correlation of TP53 mutation and genomic instability in ESCC, the amplification of CCND1, the deletion of CDKN2A/2B, and the somatic mutation of TP53 appear to play pivotal roles via G1 deregulation and therefore helps to classify this cancer into different genomic subtypes. These findings provide clinical significance that could be useful in future molecular diagnoses and therapeutic targeting.

Reservoir accumulation conditions and key exploration&development technologies for Keshen gas field in Tarim Basin

The Keshen gas field is located in the central part of Kuqa foreland thrust belt in Tarim Basin,and is another large gas field discovered in Kuqa depression after Kela 2 gas field.Since the breakthrough in 2008,a number of large and medium scale gas reservoirs including Keshen 2,Keshen 5 and Keshen 8 have been discovered,that are characterized by ultra depth,ultra-high pressure,ultra-low porosity,ultra-low permeability,high temperature and high pressure.With natural gas geological reserves of nearly trillion cubic meters and production capacity of nearly 5.5 billion cubic meters,the Keshen gas field is the main natural gas producing area in Tarim Oilfield.The Keshen gas field is located in a series of thrusting imbrication structures in the Kelasu structural belt of Kuqa foreland thrust belt.The salt roof structure,plastic rheology of salt beds and pre-salt faulted anticlinal structure constitute the large wedge-shaped thrust body.The thick delta sandstone of the Cretaceous Bashijike Formation is widely distributed,and it forms the superior reservoir-caprock combination with overlying Paleogene thick gypsum-salt bed.The deep Jurassic-Triassic oil and gas migrate vertically along fault system formed in Late Himalaya,break through the thick Cretaceous mudstone and move laterally along the fracture system of the pre-salt reservoirs,to form anticline and fault anticline high pressure reservoir groups.Through near ten years of studies,the three-dimensional seismic acquisition and processing technology for complex mountainous areas,extrusion salt-related structural modeling technology and fractured low-porosity sandstone reservoir evaluation technology have been established,which lay a foundation for realization of oil and gas exploration objectives.Logging acquisition and evaluation technology for high temperature,high pressure,ultra-deep and low-porosity sandstone gas reservoirs,and efficient development technology for fractured tight sandstone gas reservoirs have been developed,which provide a technical support for efficient exploration&development and rapid production of the Keshen gas field.

Successive Free-Radical C(sp^(2))-C(sp^(2)) Coupling Reactions to Form Graphene

Graphene is of great interest because of its exciting properties and potential applications,but its production on a large-scale still presents considerable challenges.Herein,we report the synthesis of predominately few-layer graphene,due toπ–πstacking,and single-layer graphene from reaction between hexabromobenzene and Na metal,followed by annealing to improve crystallinity.The reaction proceeds via a free-radical C(sp^(2))–C(sp^(2))coupling mechanism,which is supported by theoretical calculations.The graphene can host unpaired spin electrons,leading to a short acquisition time for a solidstate nuclear magnetic resonance 13C spectrum from unlabeled graphene,which is ascribed to the very short spin-lattice relaxation time.High catalytic activity for transforming amine to imine with a conversion of>99%and a yield of∼97%is demonstrated,and high electronic conductivity of∼105 S·m^(−1) is found by terahertz spectroscopy.The reaction delivers a method for synthesizing graphene with a high spin concentration from perbrominated benzene molecules by using an active metallic agent,such as Na,Li,or Mg.

Precision Higgs physics at the CEPC

The discovery of the Higgs boson with its mass around 125 GeV by the ATLAS and CMS Collaborations marked the beginning of a new era in high energy physics.The Higgs boson will be the subject of extensive studies of the ongoing LHC program.At the same time,lepton collider based Higgs factories have been proposed as a possible next step beyond the LHC,with its main goal to precisely measure the properties of the Higgs boson and probe potential new physics associated with the Higgs boson.The Circular Electron Positron Collider(CEPC)is one of such proposed Higgs factories.The CEPC is an e^+e^- circular collider proposed by and to be hosted in China.Located in a tunnel of approximately 100 km in circumference,it will operate at a center-of-mass energy of 240 GeV as the Higgs factory.In this paper,we present the first estimates on the precision of the Higgs boson property measurements achievable at the CEPC and discuss implications of these measurements.