Coupling of the Calculated Freezing and Thawing Front Parameterization in the Earth System Model CAS-ESM

The soil freezing and thawing process affects soil physical properties,such as heat conductivity,heat capacity,and hydraulic conductivity in frozen ground regions,and further affects the processes of soil energy,hydrology,and carbon and nitrogen cycles.In this study,the calculation of freezing and thawing front parameterization was implemented into the earth system model of the Chinese Academy of Sciences(CAS-ESM)and its land component,the Common Land Model(CoLM),to investigate the dynamic change of freezing and thawing fronts and their effects.Our results showed that the developed models could reproduce the soil freezing and thawing process and the dynamic change of freezing and thawing fronts.The regionally averaged value of active layer thickness in the permafrost regions was 1.92 m,and the regionally averaged trend value was 0.35 cm yr–1.The regionally averaged value of maximum freezing depth in the seasonally frozen ground regions was 2.15 m,and the regionally averaged trend value was–0.48 cm yr–1.The active layer thickness increased while the maximum freezing depth decreased year by year.These results contribute to a better understanding of the freezing and thawing cycle process.

Genomic Epidemiology of ST34 Monophasic Salmonella enterica Serovar Typhimurium from Clinical Patients from 2008 to 2017 in Henan,China

Salmonella enterica serovar 4,[5],12:i:-(S.4,[5],12:i:-)is a monophasic variant of Salmonella enterica serovar Typhimurium that has emerged as a global serovar causing public health concern.To date,the epidemiology and genomic characterization of this pathogen in China have not been well described.We investigated the prevalence,antimicrobial resistance(AMR)phenotypes,and population genomics of sequence type 34(ST34)S.4,[5],12:i:-among cases of human salmonellosis in Henan Province,China.A total of 100 ST34 S.4,[5],12:i:-isolates were studied from 2008 to 2017 and found mostly resistant to ampicillin(AMP),streptomycin(STR),sulfonamides(SUL),and tetracycline(TET)(ASSu T).Bayesian phylogenetic analysis demonstrated that isolates identified in China were mostly related to the European lineage and evolved into two major clades with different resistance genes and plasmid profiles.Notably,clade 1 showed a significantly higher rate of mutations in gyr A and plasmid-mediated quinolone resistance genes.The carrying of the resistance-containing region(encoding R-type ASSu T),including bla(conferring resistance to AMP),str AB(STR),sul2(SUL),and tet(B)(TET)inserted into the flj BA operon,was responsible for most of the monophasic variants in clade 2.Inc HI2 plasmids were the dominant multi-drug resistance mobile genetic elements accounting for the transmission of acquired resistance genes in this serovar,and these were more prevalent in clade 1.Our findings highlighted the increasing prevalence of multi-drug resistant S.4,[5],12:i:-in China,along with the differential characteristics of resistance gene acquisition among various lineages.Based on our data,control measures are required to address the spread of this zoonotic pathogen.Further owing to its potential origin in food-producing animals,a"One Health"approach,should be implemented to support surveillance whilst informing interventional strategies.

Development and validation of a tumor microenvironment-related prognostic signature in lung adenocarcinoma and immune infiltration analysis

Objective Tumor-infiltrating immune cells and stromal cells in the tumor microenvironment(TME)significantly affect the prognosis of and immune response to lung adenocarcinoma(LUAD).In this study,we aimed to develop a novel TME-related prognostic model based on immune and stromal genes in LUAD.Methods LUAD data from the TCGA database were used as the training cohort,and three Gene Expression Omnibus(GEO)datasets were used as the testing cohort.The Estimation of STromal and Immune cells in MAlignant Tumor tissues using Expression data algorithm was used to analyze the immune and stromal genes involved in the TME.Kaplan-Meier and Cox regression analyses were used to identify prognostic genes and construct a TME-related prognostic model.Gene set enrichment analysis and TIMER were used to analyze the immune features and signaling pathways of the model.Results A TME-related prognostic model based on six hub genes was generated that significantly stratified patients into the high-and low-risk groups in terms of overall survival.The model had strong predictive ability in both the training(TCGA)and testing(GEO)datasets and could serve as an independent prognostic factor for LUAD.Moreover,the low-risk group was characterized by greater immune cell infiltration and antitumor immune activity than the high-risk group.Importantly,the signature was closely associated with immune checkpoint molecules,which may serve as a predictor of patient response to immunotherapy.Finally,the hub genes BTK,CD28,INHA,PIK3CG,TLR4,and VEGFD were considered novel prognostic biomarkers for LUAD and were significantly correlated with immune cells.Conclusion The TME-related prognostic model could effectively predict the prognosis and reflect the TME status of LUAD.These six hub genes provided novel insights into the development of new therapeutic strategies.

模拟多年冻土活动层厚度对气候变化的响应

在气候变化背景下,活动层厚度的变化会对多年冻土区水文,生态,寒区工程等产生较大的影响.本研究利用中科院气候系统模式CAS-FGOALS-g3和陆面过程模式CAS-LSM模拟分析了活动层厚度的变化趋势和相对变化.结果表明:活动层厚度整体上呈现出增加的趋势.1979-2014年,多年冻土区活动层厚度的区域平均为1.08 m,变化趋势为0.33 cm yr-1,其变化趋势与2 m气温变化趋势基本一致,相对变化范围为1%-58%,平均为10.9%.在未来四种不同的气候情景(SSP-2.6,SSP2-4.5,SSP3-7.0和SSP5-8.5)下,到2100年预计活动层厚度的相对变化分别为10.3%,14.6%,30.1%和51%.

Increases in Anthropogenic Heat Release from Energy Consumption Lead to More Frequent Extreme Heat Events in Urban Cities

With economic development and rapid urbanization,increases in Gross Domestic Product and population in fastgrowing cities since the turn of the 21st Century have led to increases in energy consumption.Anthropogenic heat flux released to the near-surface atmosphere has led to changes in urban thermal environments and severe extreme temperature events.To investigate the effects of energy consumption on urban extreme temperature events,including extreme heat and cold events,a dynamic representation scheme of anthropogenic heat release(AHR)was implemented in the Advanced Research version of the Weather Research and Forecasting(WRF)model,and AHR data were developed based on energy consumption and population density in a case study of Beijing,China.Two simulations during 1999−2017 were then conducted using the developed WRF model with 3-km resolution with and without the AHR scheme.It was shown that the mean temperature increased with the increase in AHR,and more frequent extreme heat events were produced,with an annual increase of 0.02−0.19 days,as well as less frequent extreme cold events,with an annual decrease of 0.26−0.56 days,based on seven extreme temperature indices in the city center.AHR increased the sensible heat flux and led to surface energy budget changes,strengthening the dynamic processes in the atmospheric boundary layer that reduce AHR heating efficiency more in summer than in winter.In addition,it was concluded that suitable energy management might help to mitigate the impact of extreme temperature events in different seasons.

Progress in the diagnosis and treatment of extensive-stage small cell lung cancer

Lung cancer, being the most common cancer type, accounts for 13% of all newly diagnosed malignant tumors globally each year. Small cell lung cancer(SCLC) accounts for approximately 15% of newly diagnosed lung cancers each year, but its annual death toll accounts for 25% of that of lung cancer. We summarized relevant clinical studies to elaborate the epidemiology, pathological and clinical characteristics and the treatment status of small cell lung cancer. This paper first described the epidemiology and the pathological and clinical characteristics of SCLC and the systematic treatment of extensive-stage SCLC and then introduced the current targeted therapy and immunotherapy for SCLC to provide clinicians and patients with a more systematic, comprehensive, and beneficial treatment regimen. We expect that these studies can provide clinicians with a clear direction in molecularly targeted therapy or immunotherapy, so that a treatment approach with better antitumor effects and longer-lasting clinical benefits can be provided to the patients.

CAS-LSM Datasets for the CMIP6 Land Surface Snow and Soil Moisture Model Intercomparison Project

The datasets of the five Land-offline Model Intercomparison Project(LMIP)experiments using the Chinese Academy of Sciences Land Surface Model(CAS-LSM)of CAS Flexible Global-Ocean-Atmosphere-Land System Model Grid-point version 3(CAS FGOALS-g3)are presented in this study.These experiments were forced by five global meteorological forcing datasets,which contributed to the framework of the Land Surface Snow and Soil Moisture Model Intercomparison Project(LS3MIP)of CMIP6.These datasets have been released on the Earth System Grid Federation node.In this paper,the basic descriptions of the CAS-LSM and the five LMIP experiments are shown.The performance of the soil moisture,snow,and land-atmosphere energy fluxes was preliminarily validated using satellite-based observations.Results show that their mean states,spatial patterns,and seasonal variations can be reproduced well by the five LMIP simulations.It suggests that these datasets can be used to investigate the evolutionary mechanisms of the global water and energy cycles during the past century.

Developing the Agro-Grassland System to Insure Food Security of China

China’s food security has always been the top priority in China. As the huge increase of animal food consumption, the current agriculture system in China namely “grain farming”, whose major animal feed are grains, seems to meet a great challenge to ensure China’s food security in the future. Not only the current situation, but also the production capacity as developing grassland agriculture is analyzed in this paper. The results show that half of provinces don’t have enough grain to meet their various needs for grain, and the whole country’s potential of grain yield is reaching a limited position. On the other hand, implementing cereal-forage rotation on 20% of the total arable land and developing high productivity sown pastures on 3% of the total rangeland areas could create approximately 1.2 times Arable Land Equivalent Unit (ALEU) than ever. So changing the traditional agriculture system into Grassland Agro-Ecosystems is an effective way to insure China’s food security. It includes utilization of rangeland rationally, establishment of more sown pasture and implementation of cereal-pasture rotation system, increase livestock production, and use of arable land more efficiently.

Similarity phenomena of lean swirling flames at different bulk velocities with acoustic disturbances

In this study,flame responses to acoustic disturbances with different frequencies and amplitudes were experimentally investigated in a lean premixed swirl-stabilized combustor operating at different bulk velocities.The total heat release rate fluctuations and spatial CH*chemiluminescence distributions were captured using a photomultiplier tube and high-speed camera,respectively.The results indicate that the heat release rate exhibits a relatively drastic oscillation and high-order harmonics for low-frequency disturbances.When the bulk velocity and forcing frequency were doubled simultaneously,similar flame structures were observed in the CH*chemiluminescence distributions.As the bulk velocity increases,the gain of the Flame Describing Function(FDF)extends toward the higher frequencies,and the delay time of the flame response decreases.The similarity among FDFs at different bulk velocities was effectively captured by introducing a non-dimensional parameter,defined as the ratio of the flame response delay to the forcing time scale,to replace the dimensional forcing frequency.Furthermore,the availability of the newly defined non-dimensional parameter was verified for flames with different swirl numbers,as this played an important role in determining the flame structures and associated unsteady heat release rate.

Takagi-Sugeno fuzzy model identification for turbofan aero-engines with guaranteed stability

This paper is concerned with identifying a Takagi-Sugeno（TS） fuzzy model for turbofan aero-engines working under the maximum power status（non-afterburning）. To establish the fuzzy system, theoretical contributions are made as follows. First, by fixing antecedent parameters, the estimation of consequent parameters in state-space representations is formulated as minimizing a quadratic cost function. Second, to avoid obtaining unstable identified models, a new theorem is proposed to transform the prior-knowledge of stability into constraints. Then based on the aforementioned work, the identification problem is synthesized as a constrained quadratic optimization.By solving the constrained optimization, a TS fuzzy system is identified with guaranteed stability.Finally, the proposed method is applied to the turbofan aero-engine using simulation data generated from an aerothermodynamics component-level model. Results show the identified fuzzy model achieves a high fitting accuracy while stabilities of the overall fuzzy system and all its local models are also guaranteed.

Allocation of grassland, livestock and arable based on the spatial and temporal analysis for food demand in China

To explore the distribution of food demand and the projected trend in future food demand in China, this paper analyzed the change in current(1998–2012) percapita demand for grain, grain-consuming and herbivorous livestock products, and predicted the food demand in 2020 The results indicated that in 1998–2012, the national percapita consumption of grain ration declined by about36.66%, and the per-capita consumption of grain-consuming and herbivorous livestock products increased by about 48% and 34.09%, respectively. The grain-consuming livestock products have become the primary source of both calories and protein for consumers. The proportion of herbivorous livestock products in consumer diets has increased steadily and there has been huge potential in substituting beef and mutton for pork in this dynamic market. The demand for food in different regions of China is highly variable, which is important for planning grassland agriculture development and ensuring food safety. The demand for grain, and grain-consuming and herbivorous livestock products will increase by about3.3%, 20% and 14% respectively by 2020. Based on the food demand and trend in the development of grassland agriculture, the 31 regions in China are divided into three priority groups for grassland agriculture development.

China’s new problems of food security revealed by the Food Equivalent Unit

China's food security has a great influence on the world,and has always been the top priority in China.In recent years,as the concept of food security is evolving into one of nutrition security and the importance of food diversity is increasing,research based on nutrition security and broad food systems are increasingly needed in today’s China.Thus,not only grain for human consumption,but also animal foods have been integrated into the Food Equivalent,which is used to analyze China’s current agriculture system and reveal the water resource distribution.The results indicated that the average animal food consumption has risen by 78.6%,and now China’s daily supply of animal food per capita has reached about 50%of that in the USA and 80%of that in the South Korea.So there exist an obvious disparity in animal food supply between China and these two countries.It is impossible for the China’s current agricultural system to achieve the level in the USA.Under China’s current agricultural system,the consumption proportion of feed grain had surpassed the consumption of food grain,increased sharply from 33%in 1992 to 67%in 2011.However,the growth potential of total grain output is approaching an upper limit,so the continued growth of feed grain demand exerts great pressure on the China’s food supply.The discordance of the spatial distribution of water resource and virtual water revealed that China’s current agriculture system had a low efficiency in being able to achieve food and nutrition security.China’s current“grain farming”cannot meet the demand of increasing nutrition and appropriate resource utilization.The implementation of grassland agriculture appears feasible and necessary for saving feed grain,providing a large number of high-quality animal foods and appropriate water resource utilization.