Transport properties of Hall-type quantum states in disordered bismuthene

Bismuthene,an inherently hexagonal structure characterized by a huge bulk gap,offers a versatile platform for investigating the electronic transport of various topological quantum states.Using nonequilibrium Green's function method and Landauer-Büttiker formula,we thoroughly investigate the transport properties of various Hall-type quantum states,including quantum spin Hall(QSH)edge states,quantum valley Hall kink(QVHK)states,and quantum spin-valley Hall kink(QSVHK)states,in the presence of various disorders.Based on the exotic transport features,a spin-valley filter,capable of generating a highly spin-and valley-polarized current,is proposed.The valley index and the spin index of the filtered QSVHK state are determined by the staggered potential and the intrinsic spin-orbit coupling,respectively.The efficiency of the spin-valley filter is supported by the spacial current distribution,the valley-resolved conductance,and the spin-resolved conductance.Compared with a sandwich structure for QSVHK,our proposed spin-valley filter can work with a much smaller size and is more accessible in the experiment.

Epithelial-mesenchymal transition status of circulating tumor cells in breast cancer and its clinical relevance

Objective:Circulating tumor cells(CTCs)play a critical role in cancer metastasis,but their prevalence and significance remain unclear.This study attempted to track the epithelial-mesenchymal transition(EMT)status of CTCs in breast cancer patients and investigate their clinical relevance.Methods:In this study,the established negFACS-IF:E/M platform was applied to isolate rare CTCs and characterize their EMT status in breast cancer.A total of 89 breast cancer patients were recruited,including stage 0–III(n=60)and late stage(n=29)cases.Results:Using the negFACS-IF:E/M platform,it was found that in human epidermal growth factor receptor 2(HER2)+patients,mesenchymal CTCs usually exhibited a high percentage of HER2+cells.Stage IV breast cancer patients had considerably more CTCs than stage 0–III patients.Among stage 0–III breast cancers,the HER2 subtype included a significantly higher percentage of mesenchymal and biphenotypic(epithelial and mesenchymal)CTCs than the luminal A or B subtypes.Among stage IV patients,CTCs were predominantly epithelial in cases with local recurrence and were more mesenchymal in cases with distant metastasis.By applying a support vector machine(SVM)algorithm,the EMT status of CTCs could distinguish between breast cancer cases with metastasis/local recurrence and those without recurrence.Conclusions:The negFACS-IF:E/M platform provides a flexible and generally acceptable method for the highly sensitive and specific detection of CTCs and their EMT traits in breast cancer.This study demonstrated that the EMT status of CTCs had high clinical relevance in breast cancer,especially in predicting the distant metastasis or local recurrence of breast cancer.

Progression from ductal carcinoma in situ to invasive breast cancer:molecular features and clinical significance

Ductal carcinoma in situ(DCIS)represents pre-invasive breast carcinoma.In untreated cases,25-60%DCIS progress to invasive ductal carcinoma(IDC).The challenge lies in distinguishing between non-progressive and progressive DCIS,often resulting in over-or under-treatment in many cases.With increasing screen-detected DCIS in these years,the nature of DCIS has aroused worldwide attention.A deeper understanding of the biological nature of DCIS and the molecular journey of the DCIS-IDC transition is crucial for more effective clinical management.Here,we reviewed the key signaling pathways in breast cancer that may contribute to DCIS initiation and progression.We also explored the molecular features of DCIS and IDC,shedding light on the progression of DCIS through both inherent changes within tumor cells and alterations in the tumor microenvironment.In addition,valuable research tools utilized in studying DCIS including preclinical models and newer advanced technologies such as single-cell sequencing,spatial transcriptomics and artificial intelligence,have been systematically summarized.Further,we thoroughly discussed the clinical advancements in DCIS and IDC,including prognostic biomarkers and clinical managements,with the aim of facilitating more personalized treatment strategies in the future.Research on DCIS has already yielded significant insights into breast carcinogenesis and will continue to pave the way for practical clinical applications.

Quantitative Estimation of Pipeline Slope Disaster Risk in China

China’s economic development is closely related to oil and gas resources,and the country is investing heavily in pipeline construction.Slope geological hazards seriously affect the long-term safe operation of buried pipelines,usually causing pipeline leakage,property and environmental losses,and adverse social impacts.To ensure the safety of pipelines and reduce the probability of pipeline disasters,it is necessary to predict and quantitatively evaluate slope hazards.While there has been much research focus in recent years on the evaluation of pipeline slope disasters and the stress calculation of pipelines under hazards,existing methods only provide information on the occurrence probability of slope events,not whether a slope disaster will lead to pipeline damage.Taking the 2015 Xinzhan landslide in Guizhou Province,China,as an example,this study used discrete elements to simulate landslide events and determine the risk level and scope for pipeline damage,and then established a pipe-soil coupling model to quantitatively evaluate the impact of landslide hazards for pipelines in medium-and high-risk areas.The results provide a reference for future pipeline disaster prevention and control.

Circulating tumor cells:biology and clinical significance

Circulating tumor cells(CTCs)are tumor cells that have sloughed off the primary tumor and extravasate into and circulate in the blood.Understanding of the metastatic cascade of CTCs has tremendous potential for the identification of targets against cancer metastasis.Detecting these very rare CTCs among the massive blood cells is challenging.However,emerging technologies for CTCs detection have profoundly contributed to deepening investigation into the biology of CTCs and have facilitated their clinical application.Current technologies for the detection of CTCs are summarized herein,together with their advantages and disadvantages.The detection of CTCs is usually dependent on molecular markers,with the epithelial cell adhesion molecule being the most widely used,although molecular markers vary between different types of cancer.Properties associated with epithelial-tomesenchymal transition and stemness have been identified in CTCs,indicating their increased metastatic capacity.Only a small proportion of CTCs can survive and eventually initiate metastases,suggesting that an interaction and modulation between CTCs and the hostile blood microenvironment is essential for CTC metastasis.Single-cell sequencing of CTCs has been extensively investigated,and has enabled researchers to reveal the genome and transcriptome of CTCs.Herein,we also review the clinical applications of CTCs,especially for monitoring response to cancer treatment and in evaluating prognosis.Hence,CTCs have and will continue to contribute to providing significant insights into metastatic processes and will open new avenues for useful clinical applications.

Nucleobase,nucleoside,nucleotide,and oligonucleotide coordinated metal ions for sensing and biomedicine applications

Metal ions play critical roles in chemical,biological,and environmental processes.Various biomolecules have the ability to coordinate with metal ions and form various materials.Nucleobases,nucleosides,and nucleotides,as the essential components of DNA,have emerged as a useful building block for the construction of functional nanomaterials.In recent years,DNA oligonucleotides have also been used for this purpose.We herein review the strategies for the synthesis of soft nanomaterials through the assembly of nucleotides(or DNA)and metal ions to yield various nanoparticles,fibers,and hydrogels.Such coordination methods are simple to operate and can be carried out under ambient conditions.The luminescent,catalytic,and molecular recognition properties of these coordination materials are described with representative recent examples.Their applications ranging from biosensing,enzyme encapsulation,catalysis,templated shell growth to cancer therapy are highlighted.Finally,challenges of this field and future perspectives are discussed.

Pancreatic cancer cells render tumor-associated macrophages metabolically reprogrammed by a GARP and DNA methylation-mediated mechanism

How tumor-associated macrophages transit from a predominant antitumor M1-like phenotype to a protumoral M2-like phenotype during the development of pancreatic ductal adenocarcinoma (PDA) remains to be elucidated. We thus conducted a study by employing a PDA-macrophage co-culture system, an “orthotopic” PDA syngeneic mouse model, and human PDA specimens, together with macrophages derived from GARP knockout mice and multiple analytic tools including whole-genome RNA sequencing, DNA methylation arrays, multiplex immunohistochemistry, metabolism measurement, and invasion/metastasis assessment. Our study showed that PDA tumor cells, through direct cell–cell contact, induce DNA methylation and downregulation of a panel of glucose metabolism and OXPHOS genes selectively in M1-like macrophages, leading to a suppressed glucose metabolic status in M1-like but not in M2-like macrophages. Following the interaction with PDA tumor cells, M1-like macrophages are reprogrammed phenotypically to M2-like macrophages. The interaction between M1-like macrophages and PDA cells is mediated by GARP and integrin αV/β8, respectively. Blocking either GARP or integrin would suppress tumor-induced DNA methylation in Nqo-1 gene and the reprogramming of M1-like macrophages. Glucose-response genes such as Il-10 are subsequently activated in tumor-educated M1-like macrophages. Partly through Il-10 and its receptor Il-10R on tumor cells, M1-like macrophages functionally acquire a pro-cancerous capability. Both exogenous M1-like and M2-like macrophages promote metastasis in a mouse model of PDA while such a role of M1-like macrophages is dependent on DNA methylation. Our results suggest that PDA cells are able to reprogram M1-like macrophages metabolically and functionally through a GARP-dependent and DNA methylation-mediated mechanism to adopt a pro-cancerous fate.

Evaluation of satellite land surface albedo products over China using ground-measurements

Land surface albedo(LSA)is an important parameter in surface energy balance and global climate change.It has been used in the fields of energy budgets,climate dynamics,and land surface processes.To apply satellite LSA products more widely,the product accuracy needs to be evaluated at different scales and under atmospheric and surface conditions.This study validates and analyzes the errors of the LSA datasets from the Global LAnd Surface Satellites(GLASS)product,the European Space Agency’s Earth Observation Envelope Programme(GlobAlbedo),the Quality Assurance for Essential Climate Variables(QA4ECV)project,the Gap-filled Snow-free Bidirectional Reflectance Distribution Function(BRDF)parameters product(MCD43GF),and the Satellite Application Facility on Climate Monitoring(CM SAF)Albedo dataset from the AVHRR data(CLARA-SAL)against the Chinese Ecosystem Research Network(CERN)measurements at different spatiotemporal scales over China from 2005 to 2015.The results show that LSA estimated by GLASS agrees well with the CERN measurements on a continental scale.The GLASS product is characterized by a correlation coefficient of 0.80,a root-mean-square error of 0.09,and a mean absolute error of 0.06.The consistency between GLASS,GlobAlbedo,and CLARA-SAL is slightly lower over the regions with high aerosol optical depth(AOD)(e.g.Sichuan Basin,northern China)and high cloud cover compared with that in regions with lower AOD and low cloud cover.The estimation errors are related to varying atmospheric and surface conditions and increase with increasing AOD and cloud cover and decreasing enhanced vegetation index.Therefore,algorithms under complex atmospheric and surface conditions(e.g.high AOD,sparse vegetation)should be optimized to improve the accuracy of LSA products.

Numerical study of Klein quantum dots in graphene systems

The Klein quantum dot(KQD) refers to a quantum dot(QD) having quasi-bound states with a finite trapping time, which has been observed in experiments focusing on graphene recently. In this paper, we develop a numerical method to study the quasibound states of the KQD in graphene systems. By investigating the variation of the local density of states(LDOS) in a circular QD, we obtain the dependence of the quasi-bound states on the QD parameters, such as the electron energy, the radius and the confined potential. Based on these results, not only the experimental phenomena can be well explained, but also the crossover between quasi-bound states and real bound states is demonstrated when the intervalley scattering is included. We further study the evolution of the LDOS as the shape of the KQD varies from a circle to a semicircle. The ways of forming closed interference paths of carriers are suppressed during the deformation, and thus the corresponding quasi-bound states are eliminated. Our study reveals the mechanism of the whispering gallery mode on the quasi-bound states in graphene systems.