ⅢA-ⅡB multicomponent perovskite rare earth ferrites with promising electromagnetic wave absorption properties

Perovskite-type rare-earth ferrites(REFeO_(3))are promising materials for absorbing electromagnetic(EM)wave pollution.However,insufficient dielectric loss and poor impedance matching are key factors that limit the broader implementation of REFeO_(3).Herein,a series of multicomponent perovskite-type ferrites with strong EM wave absorption capabilities was prepared.Through the synergistic effect of chemical constitution regulation and entropy regulation,optimization of the dielectric loss and impedance matching is achieved by strengthening the structural defect mechanism,thus further adjusting the EM wave absorption performance.Compared with(LaGdSmNdBa)FeO_(3)(HE-1)and(LaGdPrSmNdBa)FeO_(3)(HE-2),(LaGdBa)FeO_(3)(ME-1)and(LaGdSmBa)FeO_(3)(ME-2)exhibit favorable performance,with optimal minimum reflection loss(RL_(min))of-56.35 dB(at 11.12 GHz)and-63.25 dB(at 7.22 GHz)and effective absorption bandwidth(EAB)of 4.46 and 4.72 GHz,respectively.This multicomponent design provides a new strategy for the development of EM wave absorption materials.

High-entropy rare earth stannate ceramics:Acid corrosion resistant radiative cooling materials with high atmospheric transparency window emissivity and high near-infrared solar reflectivity

In response to the development of the concepts of“carbon neutrality”and“carbon peak”,it is critical to developing materials with high near-infrared(NIR)solar reflectivity and high emissivity in the atmospheric transparency window(ATW;8–13μm)to advance zero energy consumption radiative cooling technology.To regulate emission and reflection properties,a series of high-entropy rare earth stannate ceramics(HE-RE_(2)Sn_(2)O_(7):(Y_(0.2)La_(0.2)Nd_(0.2)Eu_(0.2)Gd_(0.2))_(2)Sn_(2)O_(7),(Y_(0.2)La_(0.2)Sm_(0.2)Eu_(0.2)Lu_(0.2))_(2)Sn_(2)O_(7),and(Y_(0.2)La_(0.2)Gd_(0.2)Yb_(0.2)Lu_(0.2))_(2)Sn_(2)O_(7))with severe lattice distortion were prepared using a solid phase reaction followed by a pressureless sintering method for the first time.Lattice distortion is accomplished by introducing rare earth elements with different cation radii and mass.The as-synthesized HE-RE_(2)Sn_(2)O_(7)ceramics possess high ATW emissivity(91.38%–95.41%),high NIR solar reflectivity(92.74%–97.62%),low thermal conductivity(1.080–1.619 W·m^(−1)·K^(−1)),and excellent chemical stability.On the one hand,the lattice distortion intensifies the asymmetry of the structural unit to cause a notable alteration in the electric dipole moment,ultimately enlarging the ATW emissivity.On the other hand,by selecting difficult excitation elements,HE-RE_(2)Sn_(2)O_(7),which has a wide band gap(Eg),exhibits high NIR solar reflectivity.Hence,the multi-component design can effectively enhance radiative cooling ability of HE-RE_(2)Sn_(2)O_(7)and provide a novel strategy for developing radiative cooling materials.

稀土选矿药剂研究现状及展望

稀土拥有一系列优异的物理化学性质,在众多领域均有重要应用,是中国、美国、日本、澳大利亚等众多国家公认的关键矿产资源。然而稀土矿物种类繁多、品位低,常与性质相似的脉石矿物紧密共生,其选矿富集很大程度依赖于稀土选矿药剂的发展。本文以稀土资源高效选矿富集为导向,总结了矿物型稀土矿浮选药剂,含捕收剂、抑制剂、活化剂、起泡剂的研发现状及其浮选作用机理,概述了离子型稀土矿化学选矿试剂,含浸出剂、沉淀剂的研究现状及其浸矿机理,并总结和评价了当前稀土浮选捕收剂现状,最后分析了未来稀土选矿药剂的研究方向。本综述将为从事稀土选矿和分离富集技术研究或相关药剂研发的企业和工作人员提供参考。

A novel(Sm_(0.2)Eu_(0.2)Gd_(0.2)Ho_(0.2)Yb_(0.2))CrO_(3)high-entropy ceramic nanofiber as a negative temperature coefficient thermistor

The electrical properties of high-entropy ceramics(HECs)have been extensively studied in recent years due to their unique structural characteristics and fascinating functional properties induced by entropy engineering.Novel high-entropy(Sm_(0.2)Eu_(0.2)Gd_(0.2)Ho_(0.2)Yb_(0.2))CrO_(3)(HE-RECrO_(3))nanofibers were prepared by electro spinning.This work demonstrates that HE-RECrO_(3)nanofibe rs were successfully synthesized at a low temperature(800℃),which is approximately 400℃lower than the temperatures at which chromate ceramics were synthesized via the sol-gel method and the solid-state reaction method.The resistivity of HE-RECrO_(3)nanofibers decreases exponentially with increasing temperature from 25 to600℃.The logarithm of the resistivity is linearly related to the inverse of the temperature,confirming the negative temperature coefficient property of HE-RECrO_(3)nanofibers.The B_(25/50)value of the HERECrO_(3)nanofibers reaches 4072 K.In conclusion,HE-RECrO_(3)nanofibers are expected to be potential candidates for negative-temperature-coefficient(NTC)thermistors.

Long-term outcomes of lobectomy vs.sublobectomy for stage I lung invasive mucinous adenocarcinoma

To the Editor:Lung invasive mucinous adenocarcinoma(LIMA)is regarded as a subtype of invasive lung adenocarcinoma(LUAD).No significant differences exist in the overall survival(OS)or recurrence-free survival(RFS)between lobectomy and sublobectomy in clinical stage IA non small cell lung cancer(NSCLC)≤2 cm.[1]Besides,the studies on surgical methods in early LIMA are limited.In this study,we reviewed the clinicopathological features of LIMA and compared its prognosis under different surgical methods.

High-entropy(Sm_(0.2)Eu_(0.2)Gd_(0.2)Dy_(0.2)Er_(0.2))_(2)Hf_(2)O_(7) ceramic with superb resistance to radiation-induced amorphization

Nuclear engineering materials are required to possess outstanding extreme environmental tolerance and irradiation resistance.A promising novel pyrochlore-type of(Sm_(0.2)Eu_(0.2)Gd_(0.2)Dy_(0.2)Er_(0.2))2 Hf_(2)O_(7)high-entropy ceramic(HE-RE2 Hf_(2)O_(7))for control rod was prepared by solid-state reaction method.The ion irradiation of HE-RE_(2) Hf_(2)O_(7)with 400 keV Kr+at 400℃was investigated using a 400 kV ion implanter and compared with single-component pyrochlore Gd2 Hf_(2)O_(7)to evaluate the irradiation resistance.For HE-RE2 Hf_(2)O_(7),the phase transition from pyrochlore to defective fluorite is revealed after irradiation at 60 dpa.After irradiation at 120 dpa,it maintained crystalline,which is comparable to Gd2 Hf_(2)O_(7)but superior to the titanate pyrochlores previously studied.Moreover,the lattice expansion of HE-RE2 Hf_(2)O_(7)(_(0.2)2%)is much lower than that of Gd2 Hf_(2)O_(7)(0.62%),indicating excellent irradiation damage resistance.Nanoindentation tests displayed an irradiation-induced increase in hardness and a decrease in elastic modulus by about 2.6%.Irradiation-induced segregation of elements is observed on the surface of irradiated samples.In addition,HE-RE2 Hf_(2)O_(7)demonstrates a more sluggish grain growth rate than Gd2 Hf_(2)O_(7)at 1200℃,suggesting better high-temperature stability.The linear thermal expansion coefficient of HE-RE2 Hf_(2)O_(7)is 10.7×10-6 K-1 at 298–1273 K.In general,it provides a new strategy for the design of the next advanced nuclear engineering materials.

Novel Sc-doped Bi_(3)TiNbO_(9) ferroelectric nanofibers prepared by electrospinning for visible-light photocatalysis

In this work,a novel Sc-doped Bi_(3)TiNbO_(9) ferroelectric nanofiber was first prepared by electrospinning.The nanofibers are approximately 100 nm level in diameter.The photocatalytic activity analysis reveals that the Bi_(3)TiNbO_(9) nanofibers synthesized by electrospinning are superior to powders prepared by the solid-state method,which is mainly attributed to the high specific surface area and high surface activity of the nanofibers.In addition,doping Sc can reduce the band gap of Bi_(3)TiNbO_(9) and further improve the photocatalytic efficiency.Bi_(3)TiNbO_(9) nanofibers containing 5 mol%Sc have the highest photocatalytic activity,which can degrade 98.55%of RhB under 405 nm light irradiation for 120 min.In addition,the catalytic mechanism of the catalyst was obtained by scavenger tests,active species capture tests and band structure analyses.After three cycles of photocatalytic experiment,the degradation rate is decreased by only 2.42%,proving that the nanofibers catalyst has excellent stability.This work provides good prospects for the practical application of electrospinning technology in the field of photocatalysis.

Neodymium and samarium codoped PLZT ferroelectric ceramics for potential betavoltaic nuclear batteries

In this work,neodymium(Nd)and samarium(Sm)codoped lead lanthanum zirconate titanate(PLZT)ceramics were prepared by a high-temperature solid-state method.The samples were characterized by X-ray diffraction,scanning electron microscopy and ferroelectric analysis.Rare earth-doped PLZT ceramics show good phase formation.An appropriate rare earth element doping amount increases the densities of PLZT ceramics and reduces their resistivities,which is due to the role of rare earth elements in grain refinement.However,the increase in the amount of grain boundaries caused by grain refinement also affects domain inversion.Therefore,with increasing doping concentration,the remnant polarization of PLZT gradually decreases,and the doping of rare earth elements also slightly reduces the band gap of PLZT.Under irradiation with an X-ray simulated beta source with a particle energy of 10 keV(between the average energies of the beta particles of^3H and^(63)Ni),the ceramic sheets in this work produce current densities of up to 1.38 nA/cm^2.This indicates that Nd and Sm codoped PLZT ceramics have a certain potential for application in betavoltaic batteries.

Tumor-derived miR-20b-5p promotes lymphatic metastasis of esophageal squamous cell carcinoma by remodeling the tumor microenvironment

DEAREDITOR,Esophageal squamous cell carcinoma(ESCC)is one of the most common fatal malignancies worldwide and is especially common in East Asian regions,including China.Screening lymph node metastasis(LNM)-related biomarkers and elucidating the mechanism could provide promising therapeutic targets and help ESCC patients to select reasonable individual therapies.

TRAP1 Shows Clinical Significance and Promotes Cellular Migration and Invasion through STAT3/MMP2 Pathway in Human Esophageal Squamous Cell Cancer

Tumor necrosis factor receptor-associated protein 1 （TRAP1）, an important member of mitochondrial heat shock protein 90 family, is involved in multiple biological processes in several types of tumors. However, its pathological role in esophageal squamous cell cancer （ESCC） remains unknown. Herein, we demonstrated the clinical value of TRAP1, and its role in apoptosis and motility in ESCC. The clinical potential of TRAP1 was investigated through immunohistochemical analysis in 328 ESCC samples, which revealed that strong TRAP1 expression was associated with increased risk of lymph node metastasis, while high TRAP1 expression correlated with poor prognosis. Expression of TRAP1 was found to be an independent prognostic factor for patients with ESCC. Additionally, the upregulation of TRAP1 antagonized cisplatin-induced apoptosis while its downregulation sensitized cells to cisplatin-induced apoptosis. As revealed by the transwell assay, TRAP1 overexpression promoted cellular migration and invasion as compared to the control groups. In contrast, silencing of endogenous TRAP1 expression attenuated the ability of migration and invasion. Finally, the molecular mechanism investigated in the present study demonstrated that TRAP1-mediated migration and invasion occurred through STAT3/MMP2 signaling pathway. In conclusion, TRAP1 may be considered as a molecular predictive marker for prognosis and a novel molecular candidate for therapeutic target in ESCC.

Downregulation of miR-503 Promotes ESCC Cell Proliferation,Migration,and Invasion by Targeting Cyclin D1

Esophageal squamous cell carcinoma （ESCC） is one of the most aggressive cancers in China, but the underlying molecular mechanism of ESCC is still unclear. Involvement of micro- RNAs has been demonstrated in cancer initiation and progression. Despite the reported function of miR-503 in several human cancers, its detailed anti-oncogenic role and clinical significance in ESCC remain undefined. In this study, we examined miR-503 expression by qPCR and found the downregulation of miR-503 expression in ESCC tissue relative to adjacent normal tissues. Fur- ther investigation in the effect of miR-503 on ESCC cell proliferation, migration, and invasion showed that enhanced expression of miR-503 inhibited ESCC aggressive phenotype and overexpres- sion of CCND1 reversed the effect of miR-503-mediated ESCC cell aggressive phenotype. Our study further identified CCND1 as the target gene of miR-503. Thus, miR-503 functions as a tumor suppressor and has an important role in ESCC by targeting CCND1.

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

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

RASSF6-TRIM16 axis promotes cell proliferation,migration and invasion in esophageal squamous cell carcinoma

Ras-association(RA) domain family number 6(RASSF6) is a member of the Ras-association domain protein family.It is epigenetically inactive and negatively regulates the malignant progression of some tumors.However,its precise role in esophageal squamous cell carcinoma(ESCC) has not been reported.In this study,we performed immunohistochemistry(IHC) assay.The results show that RASSF6 is upregulated in ESCC and that the elevated expression level of RASSF6 is associated with lymph node metastasis and poor survival of ESCC patients.Consistent with the clinical obse rvations,the upregulation of RASSF6 greatly promotes ESCC cell proliferation,migration and invasion as well as the cell cycle transition to Gl/S phase in vitro.According to models in vivo,the downregulation of RASSF6 considerably inhibits ESCC tumor growth and lung metastasis.Mechanistically,RASSF6 negatively regulates the tumor suppressor tripartite-motif-containing protein 16(TRIM16) by promoting its ubiquitination-dependent degradation and eventually activates pathways associated with the cell cycle and epithelialmesenchymal transition(EMT).Together,these results indicate that the RASSF6-TRIM16 axis is a key effector in ESCC progression and that RASSF6 serves as a potential target for the treatment of ESCC.

miR-503-3p promotes epithelialemesenchymal transition in breast cancer by directly targeting SMAD2 and E-cadherin

Although progress in clinical and basic research has significantly increased our understanding of breast cancer, little is known about the molecular mechanism underlying breast cancer metastasis. Identification of effective therapeutic targets to prevent breast cancer metastasis is urgently needed. The function of mi R-503-3p has been investigated in other cancers, but its role in breast cancer remains undefined.Here, we found that mi R-503-3p was overexpressed in breast cancer tissue and plasma compared with adjacent normal breast tissue and with plasma from healthy individuals. Moreover, we identified mi R-503-3p to be an oncogene of breast cancer cell proliferation, migration and invasion. Upregulation of mi R-503-3p in breast cancer cells inhibited expression of epithelialemesenchymal transition（EMT）-related protein SMAD2 and the epithelial marker protein E-cadherin by directly binding to their m RNA30 untranslated region, whereas increased expression of mesenchymal marker proteins, including vimentin and N-cadherin. Taken together, our findings support a critical role for mi R-503-3p in induction of breast cancer EMT and suggest that plasma mi R-503-3p may be a useful diagnostic biomarker for breast cancer.

Transcriptional activation of Nlp by estrogen-ERa in breast cancer

Estrogen Receptor-a （ERa） is the key transcription factor that regulates cell proliferation and homeosta- sis. In this pathway, estrogen plays an important role in genomic instability and cell cycle regulation pro- cesses and the mechanisms of its action are multifaceted. In this study, we showed that estrogen regulates genomic instability through promoting the expression of Nip, a BRCAl-associated centrosomal protein which is involved in microtubule nucleation, spindle formation, chromosomal missegregation and abnormal cytokinesis. We demonstrated that the expression of Nip is strongly associated with ERa and FOXAI level in clinical breast cancer samples with poor clinical outcomes to breast cancer patients. Addition of estrogen in the ER-positive breast cancer cells resulted in elevation of NLP mRNA. Significantly, we identified that estrogen-ERa is capable of regulating Nlp expression through specifically binding ERa to the proximal region and the Estrogen Responsive Elements （ERE） enhancer in the distal region of NLP gene. Reporter assays demonstrated that estrogen directly activated Nlp promoter. ChIP assay results showed that E2-ERa directly bound to the EREs of Nip. Therefore, overexpression of Nip in breast cancer exhibits a hormone-dependent pattern, and estrogen participates in the regulation of genome instability and cell cycle in breast cancer cells partially through transcriptional activation of NLP gene. Overexpression of Nlp enhances the malignant progression of ERa-positive breast cancer cells in vitro, whereas knockdown of Nip suppresses this biological effects in ERa-positive breast cancer ceils. ERa/NIp axis may serve as a promising target against breast cancer.