Dynamic Modeling Framework of Sediment Trapped by Check-Dam Networks:A Case Study of a Typical Watershed on the Chinese Loess Plateau

Check-dam construction is an effective and widely used method for sediment trapping in the Yellow River Basin and other places over the world that are prone to severe soil erosion.Quantitative estimations of the dynamic sediment trapped by check dams are necessary for evaluating the effects of check dams and planning the construction of new ones.In this study,we propose a new framework,named soil and water assessment tool(SWAT)–dynamic check dam(DCDam),for modeling the sediment trapped by check dams dynamically,by integrating the widely utilized SWAT model and a newly developed module called DCDam.We then applied this framework to a typical loess watershed,the Yan River Basin,to assess the time-varying effects of check-dam networks over the past 60 years(1957–2016).The DCDam module generated a specific check-dam network to conceptualize the complex connections at each time step(monthly).In addition,the streamflow and sediment load simulated by using the SWAT model were employed to force the sediment routing in the check-dam network.The evaluation results revealed that the SWAT-DCDam framework performed satisfactorily,with an overestimation of 11.50%,in simulating sediment trapped by check dams,when compared with a field survey of the accumulated sediment deposition.For the Yan River Basin,our results indicated that the designed structural parameters of check dams have evolved over the past 60 years,with higher dams(37.14%and 9.22%increase for large dams and medium dams,respectively)but smaller controlled areas(46.03%and 10.56%decrease for large dams and medium dams,respectively)in recent years.Sediment retained by check dams contributed to approximately 15.00%of the total sediment load reduction in the Yan River during 1970–2016.Thus,our developed framework can be a promising tool for evaluating check-dam effects,and this study can provide valuable information and support to decision-making for soil and water conservation and check-dam planning and management.

Fiber-specific increase of carotenoid content promotes cotton fiber elongation by increasing abscisic acid and ethylene biosynthesis

Cotton fiber is a raw material for the global textile industry and fiber quality is essential to its industrial application.Carotenoids are plant secondary metabolites that may serve as dietary components,regulate light harvesting,and scavenge reactive oxygen species.Although carotenoids accumulate predominantly in rapidly elongating cotton fibers,their roles in cotton fiber development remain poorly understood.In this study,a fiber-specific promoter proSCFP was applied to drive the expression of GhOR1Del,a positive regulator of carotenoid accumulation,to upregulate the carotenoid level in cotton fiber in planta.Fiber length,strength,and fineness were increased in proSCFP:GhOR1Del transgenic cotton and abscisic acid(ABA)and ethylene contents were increased in elongating fibers.The ABA downstream regulator GhbZIP27a stimulated the expression of the ethylene synthase gene GhACO3 by binding to its promoter,suggesting that ABA promoted fiber elongation by increasing ethylene production.These findings suggest the involvement of carotenoids and ABA signaling in promoting cotton fiber elongation and provide a strategy for improving cotton fiber quality.

Flow softening and dynamic recrystallization behavior of a Mg-Gd-Y-Nd-Zr alloy under elevated temperature compressions

Flow softening behavior of a homogenized Mg-7Gd-4Y-1Nd-0.5Zr alloy under compression to a final strain of∼1.8 at elevated temperatures of 450∼550℃ and a constant strain rate of 2s^(−1) has been investigated by optical microscopy,scanning electron microscopy,electron back-scattered diffraction and transmission electron microscopy.The results show that true stress first rises to the peak point and then drops to the bottom value and increases again with further increasing strain at each temperature.Twinning dynamic recrystallization(DRX)and continuous DRX contribute to the formation of new fine grains at temperatures 450∼475℃ when the restoration is caused by both DRX and texture change due to extension twinning,resulting in the larger softening degrees compared with the softening effects owing to continuous DRX and discontinuous DRX at 500∼550℃ when twinning activation is suppressed.500℃ is the transition temperature denoting a significant decline in the contribution of twinning and TDRX to the strain with increasing temperature.The cuboid-shape phase exists in both homogenized and compressed samples,while the compositions are varied.

Can the Grain-for-Green Program Really Ensure a Low Sediment Load on the Chinese Loess Plateau?

The Chinese Loess Plateau is the most seriously eroded area in the world and contributes the vast majority of the sediment that goes into the Yellow River.Since the 1950s,progressive soil and water conservation measures have been implemented—in particular,large-scale ecological restoration has been ongoing since 1999—resulting in a significant reduction of the sediment load.However,the mechanism of the sediment transport dynamics is not fully understood due to multiple and complicated influencing factors including climate change and human activities(e.g.,ecological restoration).A challenging question,then,arises:Is the current low sediment level a“new normal”in this era and in the future?To address this question,we selected a typical loess hilly region where considerable ecological restoration has been implemented,and which is regarded as the site of the first and most representative Grainfor-Green program in the Loess Plateau.We investigated the evolution of discharge–sediment relationships in the past decades(1960–2010)and their association with the soil and water conservation measures in this area.The results showed that there was a distinct change in the regression parameters of the commonly used annual discharge–sediment regression equation—a continuously increasing trend of parameter b and a decreasing trend of parameter a,accompanying the ecological restoration.The increase in exponent b(i.e.,a steeper slope)implies a potential lower sediment load resulting from low discharge and a potential higher sediment load resulting from large discharge.This finding may question the new normal of a low sediment level and implies the potential risk of a large sediment load during extremely wet years.

Centrifugal model test on a riverine landslide in the Three Gorges Reservoir induced by rainfall and water level fluctuation

Frequent soil landslide events are recorded in the Three Gorges Reservoir area,China,making it necessary to investigate the failure mode of such riverside landslides.Geotechnical centrifugal test is considered to be the most realistic laboratory model,which can reconstruct the required geo-stress.In this study,the Liangshuijing landslide in the Three Gorgers Reservoir area is selected for a scaled centrifugal model experiment,and a water pump system is employed to retain the rainfall condition.Using the techniques of digital photography and pore water pressure transducers,water level fluctuation is controlled,and multi-physical data are thus obtained,including the pore water pressure,earth pressure,surface displacement and deep displacement.The analysis results indicate that:Three stages were set in the test(waterflooding stage,rainfall stage and drainage stage).Seven transverse cracks with wide of 1–5 mm appeared during the model test,of which 3 cracks at the toe landslide were caused by reservoir water fluctuation,and the cracks at the middle and rear part were caused by rainfall.During rainfall process,the maximum displacement of landslide model reaches 3 cm.And the maximum deformation of the model exceeds 12 cm at the drainage stage.The failure process of the slope model can be divided into four stages:microcracks appearance and propagation stage,thrust-type failure stage,retrogressive failure stage,and holistic failure stage.When the thrust-type zone caused by rainfall was connected or even overlapped with the retrogressive failure zone caused by the drainage,the landslide would start,which displayed a typical composite failure pattern.The failure mode and deformation mechanism under the coupling actions of water level fluctuation and rainfall are revealed in the model test,which could appropriately guide for the analysis and evaluation of riverside landslides.

乳腺癌患者的心理状况及相关因素分析(英文)

Sufferers of breast cancer are often plagued by various psychological problems. Mastectomy, which has a serious influence on the female sex characteristics, can bring about especially serious psychological problems. These problems affect not only the patients’ quality of life but also the beginning, development, and end of the disease. This paper reviewed the relationships between the patients’ personal factors, the disease itself, treatment factors, and other socio-psychological factors and psychological conditions so as to provide new ideas for the psychological intervention on breast cancer patients, comprehensive clinical diagnosis and treatment, and prevention and cure.

Outcomes of patients treated with SVILE vs.P-GemOx for extranodal natural killer/T-cell lymphoma,nasal type:a prospective,randomized controlled study

Objective:To compare the efficacy and safety of the novel SVILE regimen with the P-GemOx regimen in patients with newly diagnosed extranodal natural killer/T-cell lymphoma,nasal type(ND-ENKTL).Methods:From April 2015 to July 2018,103 patients with ND-ENKTL were randomly assigned to SVILE(experimental group)or P-GemOx(control group)chemotherapy followed by radiotherapy and consolidation chemotherapy.The primary endpoint was the overall response rate after 3 cycles of chemotherapy,and secondary study endpoints were complete response(CR),progression-free survival(PFS),and overall survival(OS).Safety was also evaluated.Results:There were no significant differences in baseline characteristics in the experimentalvs.control groups.In experimental and control groups,respectively,the overall response rates were 91.7%vs.97.0%for stageI/II and 75.0%vs.72.2%for stage III/IV.The CR rates were 83.4%vs.97.0%for stage I/II and 68.8%vs.61.1%for stage III/IV.None of those differences were significant.There was no significant difference in PFS and OS between groups and between patients in stage I/II and stage III/IV.The 3-year PFS and OS in stage I/II were 88.3%vs.93.3%and 88.8%vs.97.0%,respectively.The 3-year PFS and OS in stage III/IV were 46.2%vs.65.7%and 68.8%vs.72.2%,respectively.The common adverse events were hematological toxicity,hepatotoxicity,and coagulation abnormalities,which were found to be reversible with supportive therapy.Conclusions:The novel SVILE regimen has comparable effects to those of P-GemOx in patients with ND-ENKTL and is well tolerated.SVILE is a therapeutic option for ND-ENKTL.

Construction of Au@Metal-organic framework for sensitive determination of creatinine in urine

Creatinine level in urine is an important biomarker for renal function diseases,such as renal failure,glomerulonephritis,and chronic nephritis.The Au@MIL-101(Fe)was prepared by in situ growth of Au nanoparticles in MIL-101(Fe)as a selective SERS substrate.The Au@MIL-101(Fe)offers the great local surface plasmon resonance(SPR)effect due to gold nanoparticles aggre-gation inside metal-organic frameworks.The framework structure could enrich trace target samples and drag them into SPR hot spots.The optimal Au@MIL-101(Fe)composite substrate is used for analyzing creatinine in urine and the limit of detection is down to 0.1μmol/L and a linear relationship is ranging from 1μmol/L to 100μmol/L.

Toward Sustainable Revegetation in the Loess Plateau Using Coupled Water and Carbon Management

The"Grain-for-Green"project on the Loess Plateau is the largest revegetation program in the world.However,revegetation-induced land use changes can influence both water and carbon cycles,and the diverse consequences were not well understood.Therefore,the reasonability and sustainability of revegetation measures are in question.This study quantifies the impacts of revegetation-induced land use conversions on the water and carbon cycles in a typical watershed on the Loess Plateau and identifies suitable areas where revegetation of forest or grassland could benefit both soil and water conservation and carbon sequestration.We used a coupled hydro-biogeochemical model to simulate the changes of a few key components in terms of water and carbon by designing a variety of hypothetical land use conversion scenarios derived from revegetation policy.Compared to the baseline condition(land use in 2000),both sediment yield and water yield decreased substantially when replacing steep cropland with forest or grassland.Converting cropland with slopes larger than 25°,15°,and 6°to forest(CTF)would enhance the carbon sequestration with a negligible negative effect on soil water content,while replacing cropland with grassland(CTG)would result in a decline in net primary production but with a substantial increase in soil water content(3.8%-14.9%).Compared to the baseline,the soil organic carbon would increase by 0.9%-3.2% in CTF and keep relatively stable in CTG.Through testing a variety of hypothetical revegetation scenarios,we identified potential priority areas for CTF and CTG,where revegetation may be appropriate and potentially beneficial to conserving soil and water and enhancing carbon sequestration.Our study highlights the challenges in future water and carbon coupling management under revegetation policy,and our quantitative results and identification of potential areas for revegetation could provide information to policy makers for seeking optimal management on the Loess Plateau.

PI3K/Akt抑制剂渥曼青霉素对白血病细胞增殖和凋亡的影响(英文)

Objective:We studied the effects of Wortmannin (WM) on the proliferation and apoptosis of leukemia cells,and explore the possible mechanisms.Methods:The human myeloid leukemia cell line K562 was treated with different concentrations of WM,and then detected the activity of the cell proliferation by MTT assay,comet tail formation of cell DNA damage phenomenon by single cell gel electrophoresis,cell apoptosis by Annexin V-FITC/PI double staining and the expression levels of total Akt,phoshorylated Akt,NF-κB and protein in K562 cell by Western blotting,RT-PCR test before and after WM.Results:WM inhibited cell proliferation of K562 in a concentration-dependent manner,with IC50 value for 24 h being 25 nmol/L.WM induced apoptosis of K562 cells in a concentration-dependent manner,and could induce the breakage of DNA strand of K562 cell.The rate of DNA tail and the tail length of experimental groups were significantly higher than that of control group.WM may inhibit the expression of phosphorylated Akt and NF-KB protein in a dose-dependent manner in both the protein and gene levels,but no significant effect on total Akt protein.Conclusion:WM inhibited cell proliferation and induced apoptosis in K562 and concentration-dependent manner.The possible mechanism may be involved in the regulation of survival signaling pathway,such as PI3K/Akt/Nκ-KB.

Study of Celastrol on Akt Signaling Pathway and Its Roles in the Apoptosis of K562 Cells

The purpose Celastrol, the main active compound of the Celastrus genus plants, belonging to Celastraceae, has recently marked antitumour potency on solid tumours of various derivations, Methods: We demonstrate here that Celastrol also present powerful antileukaemic potency through both growth arrest and apoptosis induction in K562 cells, which was accompanied by typical apoptotic morphological and sharp decreased expression of phosphorylation level of Caspase family members and Akt signaling pathway related proteins were determined by western blot before and after celastrol treatment, and further the effect of AKT signaling pathway on celastrol-induced-apoptosis was analyzed. However, in vitro treatment with Celastrol resulted in significantly reduced expression of phophorylation of Akt, Survivin and Bcl-2 significantly in K562 cells. Results: 25 nmol/L WORT (PI3K-Akt inhibitor) can significantly augmented cell apoptosis induced by Celastrol in K562 cells in dose-dependent manner, Moreover, most Caspase3,8,6 were activated in K562 cells during Celastrol treatment, 50 μmol/Lz-VAD-fmk (Caspase inhibitor) can to enhance the apoptosis induced by Celastrol. Discussion: These results suggest that the fact that Akt signaling pathway might act as new targets of Celastrol, correlates well with the sensitivity to Celastrol, as well as the rate of apoptosis induced by Celastrol, Mechanisms that regulate Akt signaling pathway may be provide novel opportunities for drug development.

A Comparative Analysis of Sino-Thai College English Course Teaching——A Case of Comparison between Jiujiang University and Chiang Mai University

English is one of the most common languages in the world,and it has become one of the most important subjects in various countries.The native languages of China and Thailand are not English,and both countries are located in Asia and have many similarities in geographical location and cultural background.The Ministries of Education of the two countries have successively put forward relevant policies to promote the development of English education in the country.The implementation of these policies has promoted the development of college English course teaching in the country.These factors determine that the two countries have similarities in college English course teaching for Non-English majors.However,there are differences in teaching mode and teaching staff in the two countries because of their different national conditions,which make many differences,exist in college English course teaching for non-English majors in the two countries.During the author’s career as an exchange student in Chiang Mai University,she experienced the difference of college English course teaching for non-English majors in Thai universities,so the author did some researches on the basis of the understanding of English course teaching in Thai universities.Therefore,this thesis takes Sino-Thai college English course teaching for non-English majors as the research object—takes Jiujiang University and Chiang Mai University as example,and analyses their present situation from the aspects of the development and evolution,the teaching mode,and teaching staff of college English course teaching for non-English majors.On this basis,the author makes a comparative analysis of the English course teaching for non-English majors in two selected universities,then find their respective advantages and disadvantages,and put forward some suggestions on the development of Sino-Thai college English course teaching.

儿童视力自动检测系统在婴幼儿视力评价中的初步应用

目的:采用北京大学第一医院与北京大学信息科学技术学院、心理与认知科学学院共同研制开发的儿童条栅视力自动检测系统(AACP)对婴幼儿视力进行测量,探讨该系统的应用价值。方法:前瞻性临床研究。于2018年2月至2021年10月利用北京大学多个院系联合研制开发的AACP,对5个月~6岁儿童进行视力自动检测,并同时使用条栅视力检测卡(TAC-II)进行人工检测,将2种检测所得结果做对比研究。采用Wilcoxon检验进行2种视力间的差异比较,Spearman相关进行相关性分析,Bland-Altman图进行一致性分析。结果:33例(66眼)3~6岁儿童全部完成AACP与TAC-II的双眼视力检测,其中30例(54眼)儿童完成AACP与TAC-II的单眼视力检测,双眼视力检查完成率100%,单眼检查完成率90.0%。194例(388眼)5~30个月龄婴幼儿中,141例(282眼)完成2种检测方法的双眼视力检测并得到有效数据,完成率为72.7%。33例3~6岁儿童的AACP与TAC-II双眼视力及单眼视力均呈正相关(r=0.40,P=0.021;r=0.55,P<0.001)。141例5~30月龄婴幼儿的AACP与TAC-II双眼视力有较强的相关性(r=0.88,P<0.001),相关系数高于3~6岁儿童,Bland-Altman图显示90.8%的点在一致性范围内,不同月龄间AACP与TAC-II视力均存在明显正相关(r=0.82~0.94,均P<0.05),不同月龄间AACP视力差异有统计学意义(H=32.02,P<0.001),视力随月龄增长而逐渐递增。结论:AACP与TAC-II所得到的婴幼儿视力结果存在正相关,在低年龄婴幼儿中有更好的相关性和一致性。AACP有望成为适合临床条栅视力评估及婴幼儿视力筛查的检查工具。

Investigation on the mechanism of ginsenoside Rg3 in treating murine primary mammary tumor

A murine primary mammary tumor model was established to investigate the treatment with ginsenosides Rg3.The relationship between ginsenosides Rg3 and primary mammary tumor was explored.Mammary tumor was induced by using the 7,12-dimethybenz(a)anthracene(DMBA).Ginsenoside Rg3 was employed for treatment.The incidence of mammary tumor in every group was compared,and the expressions of vascular endothelial growth factor(VEGF)and microvessel density(MVD)were detected by immunohistochemical method.The cell cycle and apoptosis percentage were determined by means offlow cytometry.The incidence of tumor in treatment group was significantly lower than that in control group(60.00%vs 33.33%,P<0.05).The average diameter of mammary tumor was(0.86�0.27)cm in control group and(0.39�0.09)cm in treatment group,with the difference being significant between control and treatment groups(P<0.01).The MVD value was(31.9�5.3)in control group and(20.1�4.9)in treatment group,respectively.There was a significant difference between the two groups(P<0.05).The apoptosis percentage in control group was significantly lower than that in treatment group[(2.47�0.69)%vs(5.67�0.99)%,P<0.05].Ginsenoside Rg3 can play an antitumor role in primary mammary tumor model by inhibiting angiogenesis,cell cycle progression,and promoting cell apoptosis.