This paper aims to assess the influence of moisture content changes during rainfall on the stability of loess high-fill slopes by taking a loess high-fill slope in Lanzhou City as an example.First,according to the moi...This paper aims to assess the influence of moisture content changes during rainfall on the stability of loess high-fill slopes by taking a loess high-fill slope in Lanzhou City as an example.First,according to the moisture content monitoring data collected from a slope online monitoring system,direct shear tests were performed on soil samples of different moisture content to determine the relationship between the shear strength parameters and moisture content.Next,a coupled hydro-mechanical model with soil shear strength related to moisture content was established and used to analyze 16 working conditions with various rainfall intensities and durations for two cases:shear strength parameters from the site exploration report and those from this study.Finally,the results from the two cases were compared regarding the changes in stresses and displacements after rainfall infiltration to analyze the influence of moisture content on the stability of loess high-fill slopes.The conclusions are as follows:(1)Segmental relationship equations of cohesion and angle of internal friction were established for loess with various moisture content.(2)Under the conditions of different rainfall intensities,significant differences were observed in the trends of slope stress and displacement changes.(3)The slope displacement occurred in the shallow soil layer within about 12.5 m from the slope top,and the plastic strain concentrated in the soil layer within about 6 m from the slope top.(4)The results of slope stability analyses based on moisture content monitoring data are more in line with the observed.展开更多
Zinc-finger proteins play different roles in cancer;however,the function of zinc-finger protein ZNF575 in cancer remains unclear.In the present study,we aimed to determine the function and expression of ZNF575 in colo...Zinc-finger proteins play different roles in cancer;however,the function of zinc-finger protein ZNF575 in cancer remains unclear.In the present study,we aimed to determine the function and expression of ZNF575 in colorectal cancer.Proliferation assay,colony formation assay,and tumor model in mice were used to investigate the function of ZNF575 after ectopic expression of ZNF575 in colorectal cancer(CRC)cells.RNA sequencing,ChIP,and luciferase assays were used to investigate the mechanism behind ZNF575 regulation of CRC cell growth.The expression of ZNF575 was determined by IHC staining in 150 pairs of malignant CRC tissues,followed by prognosis analysis.We indicated that ectopic expression of ZNF575 inhibited CRC cell proliferation,colony formation and promoted cell apoptosis in vitro.Tumor growth in CRC was also impaired by ZNF575 in mice.RNA sequencing,follow-up western blotting,and qPCR results demonstrated the increase of p53,BAK,and PUMA in ZNF575-expressing CRC cells.Further results indicated that ZNF575 directly targeted the p53 promoter and promoted the transcription of p53.Downregulation of ZNF575 was confirmed in malignant tissues,and ZNF575 expression was positively correlated with the prognosis of CRC patients.The present study demonstrated the function,underlying mechanism,expression,and the prognosis-predicting role of ZNF575 in CRC,which indicated that ZNF575 would be a potential prognostic predictor and therapeutic target for CRC and other cancers.展开更多
AIM:To investigate the differentiated whole genome expression profiling of gastric high-and low-grade intraepithelial neoplasia and early-stage adenocarcinoma.METHODS:Gastric specimens from an upper magnifying chromoe...AIM:To investigate the differentiated whole genome expression profiling of gastric high-and low-grade intraepithelial neoplasia and early-stage adenocarcinoma.METHODS:Gastric specimens from an upper magnifying chromoendoscopic targeted biopsy were collected from March 2010 to May 2013.Whole genome expression profiling was performed on 19 low-grade intraepithelial neoplasia(LGIN),20 high-grade intraepithelial neoplasia(HGIN),19 early-stage adenocarcinoma(EGC),and 19 chronic gastritis tissue samples using Agilent 4×44K Whole Human Genome microarrays.Differentially expressed genes between different types of lesions were identified using an unpaired t-test and corrected with the Benjamini and Hochberg false discovery rate algorithm.A gene ontology(GO)enrichment analysis was performed using the Gene Spring software GX 12.6.The differentially expressed gene was verified using a real-time TaqManPCR assay with independent tissue samples,including 26 LGIN,15 HGIN,14 EGC,and 20 chronic gastritis.The expression of G0S2 were further validated by immunohistochemical staining(IHC)in 24 LGIN,40 HGIN,30 EGC and 61 chronic gastritis specimens.RESULTS:The gene expression patterns of LGIN and HGIN tissues were distinct.There were 2521 significantly differentially expressed transcripts in HGIN,with951 upregulated and 1570 downregulated.A GO enrichment analysis demonstrated that the most striking overexpressed transcripts in HGIN compared with LGIN were in the category of metabolism,defense response,and nuclear factorκB(NF-κB)cascade.While the vast majority of transcripts had barely altered expression in HGIN and EGC tissues,only 38 transcripts were upregulated in EGC.A GO enrichment analysis revealed that the alterations of the immune response were most prominent in the progression from HGIN to EGC.It is worth noting that,compared with LGIN,289 transcriptswere expressed at higher levels both in HGIN and EGC.A characteristic gene,G0/G1 switch 2(G0S2)was one of the 289 transcripts and related to metabolism,the immune response,and the NF-κB cascade,and its expression was validated in independent samples through real-time TaqManPCR and immunohistochemical staining.In real-time PCR analysis,the expression of G0S2 was elevated both in HGIN and EGC compared with that in LGIN(P<0.01 and P<0.001,respectively).In IHC analysis,G0S2 immunoreactivity was detected in the cytoplasmic of neoplastic cells,but was undetectable in chronic gastritis cells.The G0S2 expression in HGIN was higher than that of LGIN(P=0.012,χ2=6.28)and EGC(P=0.008,χ2=6.94).CONCLUSION:A clear biological distinction between gastric high-and low-grade intraepithelial neoplasia was identified,and provides molecular evidence for clinical application.展开更多
Isotopic signature is a powerful tool to discriminate methane(CH_(4)) source types and constrain regional and global scale CH_(4) budgets.Peatlands on the Qinghai-Tibetan Plateau are poorly understood about the isotop...Isotopic signature is a powerful tool to discriminate methane(CH_(4)) source types and constrain regional and global scale CH_(4) budgets.Peatlands on the Qinghai-Tibetan Plateau are poorly understood about the isotopic signature of CH_(4) due to the limited experimental conditions.In this study,three campaigns of diurnal air samples spacing 2-3 h were taken from an alpine peatland on the eastern Qinghai-Tibetan Plateau to investigate its source signal characteristics.Both CH_(4) concentration and its stable carbon isotope(δ^(13)C-CH_(4)) were measured to derive the carbon isotopic signature of the CH_(4) source using the Keeling plot technique.Diurnal variation patterns in CH_(4) concentration and δ^(13)C-CH_(4) were observed during summertime,with depleted δ^(13)C-CH_(4) signals and high CH_(4) concentration appearing at nighttime.The δ^(13)C-CH4 signature during summer was calculated to be-71 % ± 1.3%,which falls within the range of other wetland studies and close to high-latitude peatlands.The boundary layer dynamic and CH_(4) source were supposed to influence the measured CH_(4) concentration and δ^(13)C-CH_(4.)Further investigations of CH_(4) isotopic signals into the nongrowing season are still needed to constrain the δ^(13)C-CH_(4) signature and its environmental controls in this region.展开更多
To improve the quality of multimedia services and stimulate secure sensing in Internet of Things applications, such as healthcare and traffic monitoring, mobile crowdsensing(MCS) systems must address security threats ...To improve the quality of multimedia services and stimulate secure sensing in Internet of Things applications, such as healthcare and traffic monitoring, mobile crowdsensing(MCS) systems must address security threats such as jamming, spoofing and faked sensing attacks during both sensing and information exchange processes in large-scale dynamic and heterogeneous networks. In this article, we investigate secure mobile crowdsensing and present ways to use deep learning(DL) methods, such as stacked autoencoder, deep neural networks, convolutional neural networks, and deep reinforcement learning, to improve approaches to MCS security, including authentication, privacy protection, faked sensing countermeasures, intrusion detection and anti-jamming transmissions in MCS. We discuss the performance gain of these DLbased approaches compared to traditional security schemes and identify the challenges that must be addressed to implement these approaches in practical MCS systems.展开更多
Correction to:Acta Geochim https://doi.org/10.1007/S11631-021-00477-Z The article“Variations of methane stable isotopic values from an Alpine peatland on the eastern Qinghai-Tibetan Plaleau"written by Qian Guo,H...Correction to:Acta Geochim https://doi.org/10.1007/S11631-021-00477-Z The article“Variations of methane stable isotopic values from an Alpine peatland on the eastern Qinghai-Tibetan Plaleau"written by Qian Guo,Haijun Peng,Bing Hong,Hu Yao,Yongxuan Zhu,Hanwei Ding,Ning An,Yetang Hong was originally published electronically on the publisher's internet portal(currently SpringerLink)on 3 June 2021.There were some errors in the published article which should be corrected.The authors apologize for these errors and any confusion caused.展开更多
A compact broadband Compton spectrometer with high spectral resolution has been designed to detect spectra of laser-driven high-flux gamma rays.The primary detection range of the gamma-ray spectrum is 0.5 MeV–13 MeV,...A compact broadband Compton spectrometer with high spectral resolution has been designed to detect spectra of laser-driven high-flux gamma rays.The primary detection range of the gamma-ray spectrum is 0.5 MeV–13 MeV,although a secondary harder gamma-ray region of 13 MeV–30MeV can also be covered.The Compton-scattered electrons are spectrally resolved using a curved surface detector and a nonuniform magnetic field produced by a pair of step-like magnets.This design allows a compact structure,a wider bandwidth,especially in the lower-energy region of 0.5 MeV–2 MeV,and optimum spectral resolution.The spectral resolution is 5%–10%in the range 4 MeV–13 MeV and better than 25%in the range 0.5MeV–4MeV(with an Al converter of 0.25mmthickness and a collimator of 1 cm inner diameter).Low-Z plastic materials are used on the inner surface of the spectrometer to suppress noise due to secondary X-ray fluorescence.The spectrometer can be adjusted flexibly via a specially designed mechanical component.An algorithmbased on a regularizationmethod has also been developed to reconstruct the gamma-ray spectrum from the scattered electrons.展开更多
Composite Thin-walled Lenticular Tube(CTLT)is increasingly utilized in small satellites missions as a lightweight,foldable,and rollable structural material that facilitates the construction of large deployable systems...Composite Thin-walled Lenticular Tube(CTLT)is increasingly utilized in small satellites missions as a lightweight,foldable,and rollable structural material that facilitates the construction of large deployable systems.The CTLT is initially flattened and coiled around a central hub for storage before launch,during which elastic energy is stored as deformation energy,allowing it to be self-deployed on demand for use in orbit.This work presents a comprehensive investigation into the coiling,storage and deployment behaviors of CTLT that wraps around a central hub.A nonlinear explicit dynamic finite element model was developed with both deformable CTLT and rigidbodies mechanisms including the central hub and guide rollers,as well as the complex interactions among them.The coiling mechanics characteristics such as stored strain energy and rotational moment were presented and validated against experimental data in the literature.Then,the dynamic deployment behaviors were analyzed in terms of two different deployment methods,namely,controlled deployment and free deployment.The effect of material property change during storage was also discussed through numerical experiments.展开更多
Lithium-ion batteries(LIBs)have been widely applied in portable electronic devices and electric vehicles.With the booming of the respective markets,a huge quantity of spent LIBs that typically use either LiFePO_(4) or...Lithium-ion batteries(LIBs)have been widely applied in portable electronic devices and electric vehicles.With the booming of the respective markets,a huge quantity of spent LIBs that typically use either LiFePO_(4) or Li N_(x)Co_(y)Mn_(z)O_(2) cathode materials will be produced in the very near future,imposing significant pressure for the development of suitable disposal/recycling technologies,in terms of both environmental protection and resource reclaiming.In this review,we firstly do a comprehensive summary of the-state-of-art technologies to recycle Li N_(x)Co_(y)Mn_(z)O_(2) and LiFePO_(4)-based LIBs,in the aspects of pretreatment,hydrometallurgical recycling,and direct regeneration of the cathode materials.This closed-loop strategy for cycling cathode materials has been regarded as an ideal approach considering its economic benefit and environmental friendliness.Afterward,as for the exhausted anode materials,we focus on the utilization of exhausted anode materials to obtain other functional materials,such as graphene.Finally,the existing challenges in recycling the LiFePO_(4) and Li N_(x)Co_(y)Mn_(z)O_(2) cathodes and graphite anodes for industrial-scale application are discussed in detail;and the possible strategies for these issues are proposed.We expect this review can provide a roadmap towards better technologies for recycling LIBs,shed light on the future development of novel battery recycling technologies to promote the environmental benignity and economic viability of the battery industry and pave way for the large-scale application of LIBs in industrial fields in the near future.展开更多
Clouds are critical to the global radiation budget and hydrological cycle, but knowledge is still poor concerning the observed climatology of cloud-base height (CBH) in China. Based on fine-resolution sounding obser...Clouds are critical to the global radiation budget and hydrological cycle, but knowledge is still poor concerning the observed climatology of cloud-base height (CBH) in China. Based on fine-resolution sounding observations from the China Radiosonde Network (CRN), the method used to estimate CBH was modified, and uncertainty analyses indicated that the CBH is good enough. The accuracy of CBH estimation is verified by the comparison between the sounding-derived CBHs and those estimated from the micro-pulse lidar and millimeter-wave cloud radar. As such, the CBH climatology was compiled for the period 2006-16. Overall, the CBH exhibits large geographic variability across China, at both 0800 Local Standard Time (LST) and 2000 LST, irrespective of season. In addition, the summertime cloud base tends to be elevated to higher altitudes in dry regions [i.e., Inner Mongolia and the North China Plain (NCP)]. By comparison, the Tibetan Plateau (TP), Pearl River Delta (PRD) and Sichuan Basin (SCB) have relatively low CBHs (〈 2.4 km above ground level). In terms of seasonality, the CBH reaches its maximum in summer and minimum in winter. A low cloud base tends to occur frequently (〉 70%) over the TP, PRD and SCB. In contrast, at most sites over the Yangtze River Delta (YRD) and the NCP, about half the cloud belongs to the high-cloud category. The CBH does not exhibit marked diurnal variation in summer, throughout all CRN sites, probably due to the persistent cloud coverage caused by the East Asia Summer Monsson. To the best of our knowledge, this is the first CBH climatology produced from sounding measurements in China, and provides a useful reference for obtaining observational cloud base information.展开更多
Antiferromagnets(AFMs)with chiral noncollinear spin structure have attracted great attention in recent years.However,the existing research has mainly focused on hexagonal chiral AFMs,such as Mn3Sn,Mn3Ga,Mn3Ge with low...Antiferromagnets(AFMs)with chiral noncollinear spin structure have attracted great attention in recent years.However,the existing research has mainly focused on hexagonal chiral AFMs,such as Mn3Sn,Mn3Ga,Mn3Ge with low crystalline symmetry.Here,we present our systematical study for the face-centered cubic noncollinear antiferromagnetic Mn3Pt.By varying the alloy composition(x),we have successfully fabricated antiferromagnetic Mn1-xPtx epitaxial films on MgO substrates and have observed a crystalline structure transition from L10 MnPt to L12 Mn3Pt.The Mn3Pt exhibits a large anomalous Hall effect,which is in the same order of magnitude as those of ferromagnetic materials.Moreover,a large thickness-evolved strain effect is revealed in Mn3Pt films by X-ray diffraction(XRD)analysis based on the Scherrer method.Our work explores Mn3Pt as a promising candidate for topological antiferromagnetic spintronics.展开更多
This study compared the effects on bone metabolism and morphology of pathological obesity induced by excessive fat intake in a non-hibernator(mice)versus healthy obesity due to pre-hibernation fattening in a hibernato...This study compared the effects on bone metabolism and morphology of pathological obesity induced by excessive fat intake in a non-hibernator(mice)versus healthy obesity due to pre-hibernation fattening in a hibernator(ground squirrels).Kunming mice were fed a high-fat diet to provide a model of pathological obesity(OB group).Daurian ground squirrels fattened naturally in their pre-hibernation season(PRE group)were used as a healthy obesity model.Micro-computed tomography(micro-CT)and three-point bending tests were used to determine the microstructure and mechanical properties of bone.Western blots were used to analyze protein expression levels related to bone metabolism(Runt-related transcription factor 2(RunX2),osteocalcin(OCN),alkaline phosphatase(ALP),osteoprotegerin(OPG),receptor activator of nuclear factor-κB ligand(RANKL),cathepsin K,matrix metallopeptidase 9(MMP9),patched protein homolog 1(Ptch1),phosphorylatedβ-catenin(P-β-catenin),and glycogen synthase kinase-3β(GSK-3β)).Compared with controls,there was no obvious bone loss in the OB mice,and the stiffness of the femur was increased significantly.Compared with summer active squirrels,bone formation was enhanced but the mechanical properties did not change in the PRE group squirrels.In OB mice,western blots showed significantly increased expression levels of all proteins except RunX2,OPG,and Ptch1.PRE ground squirrels showed significantly increased expression of most proteins except OCN and Ptch1,which decreased significantly,and P-β-catenin and OPG,which did not change.In conclusion,for non-hibernating mice,moderate obesity had a certain protective effect on bones,demonstrating two-way regulation,increasing both bone loss and bone formation.For pre-hibernating ground squirrels,the healthy obesity acquired before hibernation had a positive effect on the microstructure of bones,and also enhanced the expression levels of proteins related to bone formation,bone resorption,and Wnt signaling.展开更多
With the development of tyrosine kinase inhibitor(TKI)resistance,finding the novel effective chemotherapeutic agent is of seminal importance for chronic myelogenous leukemia(CML)treatment.This study aims to find the e...With the development of tyrosine kinase inhibitor(TKI)resistance,finding the novel effective chemotherapeutic agent is of seminal importance for chronic myelogenous leukemia(CML)treatment.This study aims to find the effective anti-leukemic candidates and investigate the possible underlying mechanism.We synthesized the novel coumarin derivatives and evaluated their anti-leukemic activity.Cell viability assay revealed that compound DBH2 exhibited the potent inhibitory activity on the proliferation of CML K562 cells and TKI resistant K562 cells.Morphological observation and flow cytometry confirmed that DBH2 could selectively induce cell apoptosis and cell cycle arrest at G2/M phase of the K562 cells,which was further confirmed on the bone marrow cells from CML transgenic model mice and CD34+bone marrow leukemic cells from CML patients.Treatments of DBH2 in combination with imatinib could prolong the survival rate of SCL-tTA-BCR/ABL transgenic model mice significantly.Quantitative RT-PCR revealed that DBH2 inhibited the expression of STAT3 and STAT5 in K562 cells,and caspase-3 knockout alleviated the DBH2 induced apoptosis.Furthermore,DBH2 could induce the expression of PARP1 and ROCK1 in K562 cells,which may play the important role in caspase-dependent apoptosis.Our results concluded that coumarin derivative DBH2 serves as a promising candidate for the CML treatment,especially in the combination with imatinib for the TKI resistant CML,and STAT/caspase-3 pathway was involved in the molecular mechanism of anti-leukemic activity of DBH2.展开更多
Despite the prevalence of artificial separation of daytime and nighttime hot extremes, they may actually co-occur or occur sequentially. Considering their potential lead-lag configuration, this study identified an ent...Despite the prevalence of artificial separation of daytime and nighttime hot extremes, they may actually co-occur or occur sequentially. Considering their potential lead-lag configuration, this study identified an entire heatwave period as consecutive days with either daytime or nighttime hot extremes and investigated the changes of the prevalence and sequence of daytime and nighttime hot extremes during heatwaves over China from 1961 to 2017. It was found that the majority(82%) of heatwaves were compound heatwaves that had both daytime and nighttime hot extremes exceeding the 90 th percentile-based thresholds, while only 7%(11%) were purely daytime(nighttime) heatwaves that contained only daytime(nighttime) hot extremes. During the entire periods of compound heatwaves, daytime hot extremes usually occurred one day or a few days before nighttime hot extremes, which was in accordance with the daily variations in radiation and meteorological conditions, such as the increasing surface humidity and cloud cover, and decreasing solar radiation during the entire heatwave periods. From 1961 to2017, compound heatwave numbers exhibited the sharpest increase with a statistically significant trend of 0.44 times decade-1, in contrast to an insignificant trend of 0.00 times decade-1 for purely daytime heatwaves and a significant trend of 0.09 times decade-1 for purely nighttime heatwaves. Within the compound heatwave periods, hot nights were starting earlier and ending later, and numbers of concurrent daytime-nighttime hot extremes increased significantly at 0.20 days decade-1. In particular,urban area were not only subject to increasingly more frequent and longer compound heatwaves, but also to more occurrences of concurrent daytime-nighttime hot extremes with more serious impact. This study provides instructions for researchers to customize and select appropriate heatwave indices.展开更多
基金supported by a grant from the Gansu Provincial Department of Natural Resources Science and Technology Innovation Talent Cultivation Project(2022–09)the Geological Disaster Prevention Projects of the Gansu Provincial Bureau of Geology and Mineral Resources,and Natural Science Foundation of Gansu Province(No.22JR5RA326).
文摘This paper aims to assess the influence of moisture content changes during rainfall on the stability of loess high-fill slopes by taking a loess high-fill slope in Lanzhou City as an example.First,according to the moisture content monitoring data collected from a slope online monitoring system,direct shear tests were performed on soil samples of different moisture content to determine the relationship between the shear strength parameters and moisture content.Next,a coupled hydro-mechanical model with soil shear strength related to moisture content was established and used to analyze 16 working conditions with various rainfall intensities and durations for two cases:shear strength parameters from the site exploration report and those from this study.Finally,the results from the two cases were compared regarding the changes in stresses and displacements after rainfall infiltration to analyze the influence of moisture content on the stability of loess high-fill slopes.The conclusions are as follows:(1)Segmental relationship equations of cohesion and angle of internal friction were established for loess with various moisture content.(2)Under the conditions of different rainfall intensities,significant differences were observed in the trends of slope stress and displacement changes.(3)The slope displacement occurred in the shallow soil layer within about 12.5 m from the slope top,and the plastic strain concentrated in the soil layer within about 6 m from the slope top.(4)The results of slope stability analyses based on moisture content monitoring data are more in line with the observed.
基金supported by grants from Sichuan Provincial Science and Technology(2022NSFSC0742).
文摘Zinc-finger proteins play different roles in cancer;however,the function of zinc-finger protein ZNF575 in cancer remains unclear.In the present study,we aimed to determine the function and expression of ZNF575 in colorectal cancer.Proliferation assay,colony formation assay,and tumor model in mice were used to investigate the function of ZNF575 after ectopic expression of ZNF575 in colorectal cancer(CRC)cells.RNA sequencing,ChIP,and luciferase assays were used to investigate the mechanism behind ZNF575 regulation of CRC cell growth.The expression of ZNF575 was determined by IHC staining in 150 pairs of malignant CRC tissues,followed by prognosis analysis.We indicated that ectopic expression of ZNF575 inhibited CRC cell proliferation,colony formation and promoted cell apoptosis in vitro.Tumor growth in CRC was also impaired by ZNF575 in mice.RNA sequencing,follow-up western blotting,and qPCR results demonstrated the increase of p53,BAK,and PUMA in ZNF575-expressing CRC cells.Further results indicated that ZNF575 directly targeted the p53 promoter and promoted the transcription of p53.Downregulation of ZNF575 was confirmed in malignant tissues,and ZNF575 expression was positively correlated with the prognosis of CRC patients.The present study demonstrated the function,underlying mechanism,expression,and the prognosis-predicting role of ZNF575 in CRC,which indicated that ZNF575 would be a potential prognostic predictor and therapeutic target for CRC and other cancers.
基金Supported by The specific grants of Public-Funded Projects in the Health Industry,Grant 200902002
文摘AIM:To investigate the differentiated whole genome expression profiling of gastric high-and low-grade intraepithelial neoplasia and early-stage adenocarcinoma.METHODS:Gastric specimens from an upper magnifying chromoendoscopic targeted biopsy were collected from March 2010 to May 2013.Whole genome expression profiling was performed on 19 low-grade intraepithelial neoplasia(LGIN),20 high-grade intraepithelial neoplasia(HGIN),19 early-stage adenocarcinoma(EGC),and 19 chronic gastritis tissue samples using Agilent 4×44K Whole Human Genome microarrays.Differentially expressed genes between different types of lesions were identified using an unpaired t-test and corrected with the Benjamini and Hochberg false discovery rate algorithm.A gene ontology(GO)enrichment analysis was performed using the Gene Spring software GX 12.6.The differentially expressed gene was verified using a real-time TaqManPCR assay with independent tissue samples,including 26 LGIN,15 HGIN,14 EGC,and 20 chronic gastritis.The expression of G0S2 were further validated by immunohistochemical staining(IHC)in 24 LGIN,40 HGIN,30 EGC and 61 chronic gastritis specimens.RESULTS:The gene expression patterns of LGIN and HGIN tissues were distinct.There were 2521 significantly differentially expressed transcripts in HGIN,with951 upregulated and 1570 downregulated.A GO enrichment analysis demonstrated that the most striking overexpressed transcripts in HGIN compared with LGIN were in the category of metabolism,defense response,and nuclear factorκB(NF-κB)cascade.While the vast majority of transcripts had barely altered expression in HGIN and EGC tissues,only 38 transcripts were upregulated in EGC.A GO enrichment analysis revealed that the alterations of the immune response were most prominent in the progression from HGIN to EGC.It is worth noting that,compared with LGIN,289 transcriptswere expressed at higher levels both in HGIN and EGC.A characteristic gene,G0/G1 switch 2(G0S2)was one of the 289 transcripts and related to metabolism,the immune response,and the NF-κB cascade,and its expression was validated in independent samples through real-time TaqManPCR and immunohistochemical staining.In real-time PCR analysis,the expression of G0S2 was elevated both in HGIN and EGC compared with that in LGIN(P<0.01 and P<0.001,respectively).In IHC analysis,G0S2 immunoreactivity was detected in the cytoplasmic of neoplastic cells,but was undetectable in chronic gastritis cells.The G0S2 expression in HGIN was higher than that of LGIN(P=0.012,χ2=6.28)and EGC(P=0.008,χ2=6.94).CONCLUSION:A clear biological distinction between gastric high-and low-grade intraepithelial neoplasia was identified,and provides molecular evidence for clinical application.
基金financially supported by the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No.XDB40010000)the National Natural Science Foundation of China (Grant Nos.41907288,41673119,and 41773140)+1 种基金the Science and Technology Foundation of Guizhou Province (Grant Nos.[2019]1317 and [2020]1Y193)supported by the“Light of West China”Program and the CAS Scholarship。
文摘Isotopic signature is a powerful tool to discriminate methane(CH_(4)) source types and constrain regional and global scale CH_(4) budgets.Peatlands on the Qinghai-Tibetan Plateau are poorly understood about the isotopic signature of CH_(4) due to the limited experimental conditions.In this study,three campaigns of diurnal air samples spacing 2-3 h were taken from an alpine peatland on the eastern Qinghai-Tibetan Plateau to investigate its source signal characteristics.Both CH_(4) concentration and its stable carbon isotope(δ^(13)C-CH_(4)) were measured to derive the carbon isotopic signature of the CH_(4) source using the Keeling plot technique.Diurnal variation patterns in CH_(4) concentration and δ^(13)C-CH_(4) were observed during summertime,with depleted δ^(13)C-CH_(4) signals and high CH_(4) concentration appearing at nighttime.The δ^(13)C-CH4 signature during summer was calculated to be-71 % ± 1.3%,which falls within the range of other wetland studies and close to high-latitude peatlands.The boundary layer dynamic and CH_(4) source were supposed to influence the measured CH_(4) concentration and δ^(13)C-CH_(4.)Further investigations of CH_(4) isotopic signals into the nongrowing season are still needed to constrain the δ^(13)C-CH_(4) signature and its environmental controls in this region.
基金supported in part by the National Natural Science Foundation of China under Grant 61671396 and 91638204in part by the open research fund of National Mobile Communications Research Laboratory,Southeast University(No.2018D08)in part by Science and Technology Innovation Project of Foshan City,China(Grant No.2015IT100095)
文摘To improve the quality of multimedia services and stimulate secure sensing in Internet of Things applications, such as healthcare and traffic monitoring, mobile crowdsensing(MCS) systems must address security threats such as jamming, spoofing and faked sensing attacks during both sensing and information exchange processes in large-scale dynamic and heterogeneous networks. In this article, we investigate secure mobile crowdsensing and present ways to use deep learning(DL) methods, such as stacked autoencoder, deep neural networks, convolutional neural networks, and deep reinforcement learning, to improve approaches to MCS security, including authentication, privacy protection, faked sensing countermeasures, intrusion detection and anti-jamming transmissions in MCS. We discuss the performance gain of these DLbased approaches compared to traditional security schemes and identify the challenges that must be addressed to implement these approaches in practical MCS systems.
文摘Correction to:Acta Geochim https://doi.org/10.1007/S11631-021-00477-Z The article“Variations of methane stable isotopic values from an Alpine peatland on the eastern Qinghai-Tibetan Plaleau"written by Qian Guo,Haijun Peng,Bing Hong,Hu Yao,Yongxuan Zhu,Hanwei Ding,Ning An,Yetang Hong was originally published electronically on the publisher's internet portal(currently SpringerLink)on 3 June 2021.There were some errors in the published article which should be corrected.The authors apologize for these errors and any confusion caused.
基金ACKNOWLEDGMENTS This work was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB16000000)the National Natural Science Foundation of China(Grant Nos.11775223,11375197,11605200,and 11275202)+1 种基金the Science Challenge Project(Grant No.TZ2016005)the Open Fund of the State Key Laboratory of High Field Laser Physics(SIOM).
文摘A compact broadband Compton spectrometer with high spectral resolution has been designed to detect spectra of laser-driven high-flux gamma rays.The primary detection range of the gamma-ray spectrum is 0.5 MeV–13 MeV,although a secondary harder gamma-ray region of 13 MeV–30MeV can also be covered.The Compton-scattered electrons are spectrally resolved using a curved surface detector and a nonuniform magnetic field produced by a pair of step-like magnets.This design allows a compact structure,a wider bandwidth,especially in the lower-energy region of 0.5 MeV–2 MeV,and optimum spectral resolution.The spectral resolution is 5%–10%in the range 4 MeV–13 MeV and better than 25%in the range 0.5MeV–4MeV(with an Al converter of 0.25mmthickness and a collimator of 1 cm inner diameter).Low-Z plastic materials are used on the inner surface of the spectrometer to suppress noise due to secondary X-ray fluorescence.The spectrometer can be adjusted flexibly via a specially designed mechanical component.An algorithmbased on a regularizationmethod has also been developed to reconstruct the gamma-ray spectrum from the scattered electrons.
基金co-supported by the National Natural Science Foundation of China(No.12202295)the Fundamental Research Funds for the Central Universities,China(No.YJ2021137)+1 种基金the Open Project of State Key Laboratory for Strength and Vibration of Mechanical Structures,Xi’an Jiaotong University,China(No.SV2021-KF-04)the Open Project of State Key Laboratory of Structural Analysis for Industrial Equipment,Dalian University of Technology,China(No.GZ22120)。
文摘Composite Thin-walled Lenticular Tube(CTLT)is increasingly utilized in small satellites missions as a lightweight,foldable,and rollable structural material that facilitates the construction of large deployable systems.The CTLT is initially flattened and coiled around a central hub for storage before launch,during which elastic energy is stored as deformation energy,allowing it to be self-deployed on demand for use in orbit.This work presents a comprehensive investigation into the coiling,storage and deployment behaviors of CTLT that wraps around a central hub.A nonlinear explicit dynamic finite element model was developed with both deformable CTLT and rigidbodies mechanisms including the central hub and guide rollers,as well as the complex interactions among them.The coiling mechanics characteristics such as stored strain energy and rotational moment were presented and validated against experimental data in the literature.Then,the dynamic deployment behaviors were analyzed in terms of two different deployment methods,namely,controlled deployment and free deployment.The effect of material property change during storage was also discussed through numerical experiments.
基金supported by the National Natural Science Foundation of China(Nos.51072130,51502045 and 21905202)the Australian Research Council(ARC)through Discovery Early Career Researcher Award(DECRA,No.DE170100871)program。
文摘Lithium-ion batteries(LIBs)have been widely applied in portable electronic devices and electric vehicles.With the booming of the respective markets,a huge quantity of spent LIBs that typically use either LiFePO_(4) or Li N_(x)Co_(y)Mn_(z)O_(2) cathode materials will be produced in the very near future,imposing significant pressure for the development of suitable disposal/recycling technologies,in terms of both environmental protection and resource reclaiming.In this review,we firstly do a comprehensive summary of the-state-of-art technologies to recycle Li N_(x)Co_(y)Mn_(z)O_(2) and LiFePO_(4)-based LIBs,in the aspects of pretreatment,hydrometallurgical recycling,and direct regeneration of the cathode materials.This closed-loop strategy for cycling cathode materials has been regarded as an ideal approach considering its economic benefit and environmental friendliness.Afterward,as for the exhausted anode materials,we focus on the utilization of exhausted anode materials to obtain other functional materials,such as graphene.Finally,the existing challenges in recycling the LiFePO_(4) and Li N_(x)Co_(y)Mn_(z)O_(2) cathodes and graphite anodes for industrial-scale application are discussed in detail;and the possible strategies for these issues are proposed.We expect this review can provide a roadmap towards better technologies for recycling LIBs,shed light on the future development of novel battery recycling technologies to promote the environmental benignity and economic viability of the battery industry and pave way for the large-scale application of LIBs in industrial fields in the near future.
基金the Ministry of Science and Technology of China (Grant Nos. 2017YFC1501701, 2017YFC1501401, 2017YFA0603501 and 2016YFA0600403)the National Natural Science Foundation of China (Grant Nos. 91544217, 41771399 and 41471301)+1 种基金the Chinese Academy of Meteorological Sciences (Grant Nos. 2017Z005 and 2017R001)the Fundamental Research Funds for the Central Universities (Grant No. 2017STUD17)
文摘Clouds are critical to the global radiation budget and hydrological cycle, but knowledge is still poor concerning the observed climatology of cloud-base height (CBH) in China. Based on fine-resolution sounding observations from the China Radiosonde Network (CRN), the method used to estimate CBH was modified, and uncertainty analyses indicated that the CBH is good enough. The accuracy of CBH estimation is verified by the comparison between the sounding-derived CBHs and those estimated from the micro-pulse lidar and millimeter-wave cloud radar. As such, the CBH climatology was compiled for the period 2006-16. Overall, the CBH exhibits large geographic variability across China, at both 0800 Local Standard Time (LST) and 2000 LST, irrespective of season. In addition, the summertime cloud base tends to be elevated to higher altitudes in dry regions [i.e., Inner Mongolia and the North China Plain (NCP)]. By comparison, the Tibetan Plateau (TP), Pearl River Delta (PRD) and Sichuan Basin (SCB) have relatively low CBHs (〈 2.4 km above ground level). In terms of seasonality, the CBH reaches its maximum in summer and minimum in winter. A low cloud base tends to occur frequently (〉 70%) over the TP, PRD and SCB. In contrast, at most sites over the Yangtze River Delta (YRD) and the NCP, about half the cloud belongs to the high-cloud category. The CBH does not exhibit marked diurnal variation in summer, throughout all CRN sites, probably due to the persistent cloud coverage caused by the East Asia Summer Monsson. To the best of our knowledge, this is the first CBH climatology produced from sounding measurements in China, and provides a useful reference for obtaining observational cloud base information.
基金the National Key R&D Program of China(Grant Nos.2017YFA0303202,and 2017YFA0305300)the National Natural Science Foundation of China(Grant Nos.11974260,11674246,51501131,51671147,11874283,51801152,and 11774064)+1 种基金the Natural Science Foundation of Shanghai(Grant Nos.17ZR1443700,and19ZR1478700)the Fundamental Research Funds for the Central Universities。
文摘Antiferromagnets(AFMs)with chiral noncollinear spin structure have attracted great attention in recent years.However,the existing research has mainly focused on hexagonal chiral AFMs,such as Mn3Sn,Mn3Ga,Mn3Ge with low crystalline symmetry.Here,we present our systematical study for the face-centered cubic noncollinear antiferromagnetic Mn3Pt.By varying the alloy composition(x),we have successfully fabricated antiferromagnetic Mn1-xPtx epitaxial films on MgO substrates and have observed a crystalline structure transition from L10 MnPt to L12 Mn3Pt.The Mn3Pt exhibits a large anomalous Hall effect,which is in the same order of magnitude as those of ferromagnetic materials.Moreover,a large thickness-evolved strain effect is revealed in Mn3Pt films by X-ray diffraction(XRD)analysis based on the Scherrer method.Our work explores Mn3Pt as a promising candidate for topological antiferromagnetic spintronics.
基金supported by the National Natural Science Foundation of China(Nos.31640072 and 31900338)the Natural Science Basic Research Program of Shaanxi(No.2020JM-428),China.
文摘This study compared the effects on bone metabolism and morphology of pathological obesity induced by excessive fat intake in a non-hibernator(mice)versus healthy obesity due to pre-hibernation fattening in a hibernator(ground squirrels).Kunming mice were fed a high-fat diet to provide a model of pathological obesity(OB group).Daurian ground squirrels fattened naturally in their pre-hibernation season(PRE group)were used as a healthy obesity model.Micro-computed tomography(micro-CT)and three-point bending tests were used to determine the microstructure and mechanical properties of bone.Western blots were used to analyze protein expression levels related to bone metabolism(Runt-related transcription factor 2(RunX2),osteocalcin(OCN),alkaline phosphatase(ALP),osteoprotegerin(OPG),receptor activator of nuclear factor-κB ligand(RANKL),cathepsin K,matrix metallopeptidase 9(MMP9),patched protein homolog 1(Ptch1),phosphorylatedβ-catenin(P-β-catenin),and glycogen synthase kinase-3β(GSK-3β)).Compared with controls,there was no obvious bone loss in the OB mice,and the stiffness of the femur was increased significantly.Compared with summer active squirrels,bone formation was enhanced but the mechanical properties did not change in the PRE group squirrels.In OB mice,western blots showed significantly increased expression levels of all proteins except RunX2,OPG,and Ptch1.PRE ground squirrels showed significantly increased expression of most proteins except OCN and Ptch1,which decreased significantly,and P-β-catenin and OPG,which did not change.In conclusion,for non-hibernating mice,moderate obesity had a certain protective effect on bones,demonstrating two-way regulation,increasing both bone loss and bone formation.For pre-hibernating ground squirrels,the healthy obesity acquired before hibernation had a positive effect on the microstructure of bones,and also enhanced the expression levels of proteins related to bone formation,bone resorption,and Wnt signaling.
基金This project was reviewed and approved by the ethical committee of Tangdu Hospital,Air Force Medical University(No.201903-87).
文摘With the development of tyrosine kinase inhibitor(TKI)resistance,finding the novel effective chemotherapeutic agent is of seminal importance for chronic myelogenous leukemia(CML)treatment.This study aims to find the effective anti-leukemic candidates and investigate the possible underlying mechanism.We synthesized the novel coumarin derivatives and evaluated their anti-leukemic activity.Cell viability assay revealed that compound DBH2 exhibited the potent inhibitory activity on the proliferation of CML K562 cells and TKI resistant K562 cells.Morphological observation and flow cytometry confirmed that DBH2 could selectively induce cell apoptosis and cell cycle arrest at G2/M phase of the K562 cells,which was further confirmed on the bone marrow cells from CML transgenic model mice and CD34+bone marrow leukemic cells from CML patients.Treatments of DBH2 in combination with imatinib could prolong the survival rate of SCL-tTA-BCR/ABL transgenic model mice significantly.Quantitative RT-PCR revealed that DBH2 inhibited the expression of STAT3 and STAT5 in K562 cells,and caspase-3 knockout alleviated the DBH2 induced apoptosis.Furthermore,DBH2 could induce the expression of PARP1 and ROCK1 in K562 cells,which may play the important role in caspase-dependent apoptosis.Our results concluded that coumarin derivative DBH2 serves as a promising candidate for the CML treatment,especially in the combination with imatinib for the TKI resistant CML,and STAT/caspase-3 pathway was involved in the molecular mechanism of anti-leukemic activity of DBH2.
基金supported by the National Key R&D Program(Grant No.2016YFA0601502)the National Natural Science Foundation of China(Grant Nos.41822503 and 41375092).
文摘Despite the prevalence of artificial separation of daytime and nighttime hot extremes, they may actually co-occur or occur sequentially. Considering their potential lead-lag configuration, this study identified an entire heatwave period as consecutive days with either daytime or nighttime hot extremes and investigated the changes of the prevalence and sequence of daytime and nighttime hot extremes during heatwaves over China from 1961 to 2017. It was found that the majority(82%) of heatwaves were compound heatwaves that had both daytime and nighttime hot extremes exceeding the 90 th percentile-based thresholds, while only 7%(11%) were purely daytime(nighttime) heatwaves that contained only daytime(nighttime) hot extremes. During the entire periods of compound heatwaves, daytime hot extremes usually occurred one day or a few days before nighttime hot extremes, which was in accordance with the daily variations in radiation and meteorological conditions, such as the increasing surface humidity and cloud cover, and decreasing solar radiation during the entire heatwave periods. From 1961 to2017, compound heatwave numbers exhibited the sharpest increase with a statistically significant trend of 0.44 times decade-1, in contrast to an insignificant trend of 0.00 times decade-1 for purely daytime heatwaves and a significant trend of 0.09 times decade-1 for purely nighttime heatwaves. Within the compound heatwave periods, hot nights were starting earlier and ending later, and numbers of concurrent daytime-nighttime hot extremes increased significantly at 0.20 days decade-1. In particular,urban area were not only subject to increasingly more frequent and longer compound heatwaves, but also to more occurrences of concurrent daytime-nighttime hot extremes with more serious impact. This study provides instructions for researchers to customize and select appropriate heatwave indices.