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The electrochemical formation of liquid sulfur at room temperature on the basal plane of MoS

EGFR exon 20 insertion mutation is a rare mutation subtype of EGFR mutations, with no approved treatment in China so far. The clinical treatments of advanced EGFR exon 20 insertion mutations in non-small cell lung cancer (NSCLC) are mainly based on EGFR-TKI, chemotherapy, ICI, and other therapies. However, the efficacy is not satisfactory. Aumolertinib is the third-generation EGFR-TKI independently developed in China, which has shown excellent efficacy and safety in phase 2 and 3 clinical trials. This study aimed to share a case of applying aumolertinib as the core combined with other treatments for a patient with multiple metastases in NSCLC with an uncommon site of EGFR exon 20 insertion mutations. The comprehensive treatment benefited the patient in terms of 10 months of progression-free survival and a significant improvement in quality of life. We discussed whether we could further explore the potential of aumolertinib in treating EGFR exon 20 insertion mutations through this case report.

Deciphering the atomic and electronic structures of interfaces is key to developing state-of-the-art perovskite semiconductors. However, conventional characterization techniques have limited previous studies mainly to grain-boundary interfaces, whereas the intragrain-interface microstructures and their electronic properties have been much less revealed. Herein using scanning transmission electron microscopy, we resolved the atomic-scale structural information on three prototypical intragrain interfaces, unraveling intriguing features clearly different from those from previous observations based on standalone films or nanomaterial samples. These intragrain interfaces include composition boundaries formed by heterogeneous ion distribution, stacking faults resulted from wrongly stacked crystal planes, and symmetrical twinning boundaries. The atomic-scale imaging of these intragrain interfaces enables us to build unequivocal models for the ab initio calculation of electronic properties. Our results suggest that these structure interfaces are generally electronically benign, whereas their dynamic interaction with point defects can still evoke detrimental effects. This work paves the way toward a more complete fundamental understanding of the microscopic structure–property–performance relationship in metal halide perovskites.

Angiogenesis is the process of capillary sprouting from pre-existing vessels and it plays a critical role in the carcinogenic process of lung adenocarcinoma (LUAD). However, the association of angiogenesis regulators with the prognosis and progression of LUAD needs to be further elucidated. In this study, we adopted differential expression analysis, Cox proportional hazards (PH) regression analysis and experimental validation to identify angiogenesis regulators correlated with a poor prognosis, immune infiltration and cancer progression in LUAD. These results showed that the diagnostic and prognostic models based on COL5A2 and EPHB2 served as independent biomarkers with superior predictive ability. The patients in the high-risk group exhibited a worse prognosis in the TCGA cohort (P

Tumor-associated macrophages (TAMs) play an important role in remodeling the tumor microenvironment (TME), which promotes tumor growth, immunosuppression and angiogenesis. Because of the high plasticity of macrophages and the extremely complex tumor microenvironment, the mechanism of TAMs in cancer progression is still largely unknown. In this study, we found that xCT (SLC7A11) was overexpressed in lung cancer-associated macrophages. Higher xCT in TAMs was associated with poor prognosis and was an independent predictive factor in lung cancer. In addition, lung cancer growth and progression was inhibited in xCT knockout mice, especially macrophage-specific xCT knockout mice. We also found that the deletion of macrophage xCT inhibited AKT/STAT6 signaling activation and reduced M2-type polarization of TAMs. Macrophage xCT deletion recruited more CD8

Circulating tumor cells (CTCs) are shed from primary or metastatic tumors into the peripheral blood circulation which carry a wealth of information for cancer diagnosis, treatment and prognosis. However, most of current CTCs isolation and detection methods provide only cancer cell counting information which is far from meeting clinical needs. In addition to the numbers of CTCs, the target proteins and gene mutations carried by CTCs can also be used for clinical diagnosis, disease monitoring and therapeutic selection. In this work, we develop a novel microfluidic-based CTCs separation and enrichment platform that enables the extraction of CTCs information, including cell number, epithelial-mesenchymal transition (EMT) subtypes, protein expression levels, and target gene mutations. The platform offers a high CTCs recovery rate (> 85%), high CTCs purification (∼104 enrichment) and intact viable CTCs for downstream analysis. This platform can successfully enrich tumor cells from a 4 mL blood sample within 15 minutes. CTCs were detected in clinical samples from cancer patients with a detection rate of 95.8%. Furthermore, the CTCs subtypes (epithelial, mesenchymal or mix type), the expression levels of selected proteins (PD-L1, HER2, VEGF), and the target mutations in selected genes (EGFR, KRAS, BRAF) could also be directly analyzed by immunofluorescence and digital PCR for clinical utility. PD-L1 expression detected in the CTCs was consistent with the immunohistochemical results. This microfluidic-based CTCs enrichment platform and downstream molecular analysis provide a possible alternative to tissue biopsy for precision cancer management, especially for patients whose tissue biopsies are unavailable.

X-ray detectors need to be operated at as low as possible doses to reduce radiation health risks during x-ray security examination or medical inspection, which drives the efforts to explore novel detectors with high sensitivity and low detection limits. Organolead trihalide perovskite is the champion, with the highest sensitivity and lowest detection limit. Unfortunately, these materials threaten the safety of the human body and environment by the toxic issue of lead. Here we present a new environmentally friendly material with van der Waals heterostructure of BixIy for ultra-sensitive x-ray detection. The BixIy detector provides anisotropic x-ray detecting performance with a sensitivity up to 1.3×105 µC Gy− 1 cm− 2 and a detection limit as low as 34 nGy s− 1. Meanwhile, our BixIy detector demonstrates wonderful environmental and hard radiation stabilities. Our discovery inspires the search for new van der Waals heterostructure classes to realize high-performance x-ray detectors and other optoelectronic devices without employing toxic elements.

Two-dimensional materials with out-of-plane (OOP) ferroelectric and piezoelectric properties are highly desirable for the realization of ultrathin ferro- and piezoelectronic devices. We demonstrate unexpected OOP ferroelectricity and piezoelectricity in untwisted, commensurate, and epitaxial MoS 2 /WS 2 heterobilayers synthesized by scalable one-step chemical vapor deposition. We show d 33 piezoelectric constants of 1.95 to 2.09 picometers per volt that are larger than the natural OOP piezoelectric constant of monolayer In 2 Se 3 by a factor of ~6. We demonstrate the modulation of tunneling current by about three orders of magnitude in ferroelectric tunnel junction devices by changing the polarization state of MoS 2 /WS 2 heterobilayers. Our results are consistent with density functional theory, which shows that both symmetry breaking and interlayer sliding give rise to the unexpected properties without the need for invoking twist angles or moiré domains.

The vital regulation of abnormally expressed lncRNAs in human cancers has been identified. This study is aimed at illustrating the role of LINC01426 in influencing malignant behaviors of lung adenocarcinoma (LUAD) and the possible mechanism. Differential expressions of LINC01426 in a downloaded profile containing LUAD and normal tissues were analyzed using Gene Expression Profiling Interactive Analysis (GEPIA) database and were reconfirmed in clinical samples collected in our hospital. In addition, LINC01426 level in lung carcinoma cell lines was detected by quantitative real-time polymerase chain reaction (qRT-PCR) as well. The relationship between LINC01426 expression and the age, tumor node metastasis (TNM) staging, lymphatic metastasis, tumor differentiation, and overall survival of LUAD was analyzed. After intervening LINC01426 level in H1299 and PC9 cells, proliferative and metastatic changes were assessed by functional experiments. LINC01426 was upregulated in LUAD tissues and cell lines. Its level was closely linked to TNM staging, lymphatic metastasis, tumor differentiation, and overall survival of LUAD. Knockdown of LINC01426 suppressed proliferative and metastatic abilities in H1299 and PC9 cells. LINC01246 is upregulated in LUAD samples and predicts a poor prognosis. It drives malignant process of LUAD via stimulating proliferative and metastatic abilities.

Halide perovskites are promising for a spectrum of energy applications including photovoltaics. Decisively characterizing microstructures of perovskites is critical yet challenging due to their soft characteristics. Recently, Rothmann et al. employed low-dose, low-angle annular dark-field scanning transmission electron microscopy to image perovskite thin films at the atomic scale, unveiling key structural details that are invisible to previous observations. This study opens the door to revealing microscopic structure-property-performance relationships in perovskites and beyond, guiding the reinvention and optimization of energy devices.

Objective Tracheobronchial mucoepidermoid carcinoma (TMEC) is an extremely rare salivary gland-type neoplasm. We aimed to explore the clinical characteristics and prognosis of TMEC and to compare them with those of another rare salivary gland-type neoplasm, tracheobronchial adenoid cystic carcinoma (TACC). Method We performed a retrospective review of all patients pathologically diagnosed with TMEC between 1965 and 2017 at our institution. We reviewed the patients’ clinical characteristics, treatment methods and outcomes and compared the results of TMEC and TACC patients. Results A total of 115 consecutive patients, including 107 who underwent surgery and 8 who received nonoperative therapy, were included in our study. The 1-, 2-, and 5-year survival rates were 97.89%, 94.17%, and 90.50%, respectively, in the surgical group and 83.33%, 41.67% and 0.00%, respectively, in the nonoperative group. The multivariate analysis showed that N stage was an independent prognostic factor for overall survival (OS). TMEC patients were younger, had a shorter complaint duration, had fewer symptoms, had more bronchial tumors, and were more likely to undergo surgical treatment and achieve an R0 resection (surgically treated patients) than TACC patients; furthermore, TMEC patients had a significantly better OS than TACC patients (P Conclusions TMEC has different characteristics and a better prognosis than TACC, which may reflect the different biological behaviors of these two salivary gland neoplasms. Radical treatment and close follow-up are critical for surgically treated TMEC patients with lymph node metastasis.

Van der Waals (vdW) integration affords semiconductor heterostructures without constrains of lattice matching and opens up a new realm of functional devices by design. A particularly interesting approach is the electrochemical intercalation of two-dimensional (2D) atomic crystal and formation of superlattices, which can provide scalable production of novel vdW heterostructures. However, this approach has been limited to the use of organic cations with non-functional aliphatic chains, therefore failed to take the advantage of the vast potentials in molecular functionalities (electronic, photonic, magnetic, etc.). Here we report the integration of 2D crystal (MoS2, WS2, highly oriented pyrolytic graphite (HOPG), WSe2 as model systems) with electrochemically inert organic molecules that possess semiconducting characteristics (including perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA), pentacene and fullerene), through on-chip electrochemical intercalation. An unprecedented long-range spatial feature of intercalation has been achieved, which allowed facile assembly of a vertical MoS2-PTCDA-Si junction. The intercalated heterostructure shows significant modulation of the lateral transport, and leads to a molecular tunneling characteristic at the vertical direction. The general intercalation of charge neutral and functional molecules defines a versatile platform of inorganic/organic hybrid vdW heterostructures with significantly extended molecular functional building blocks, holding great promise in future design of nano/quantum devices.

Topological domains in ferroelectrics have received much attention recently owing to their novel functionalities and potential applications in electronic devices. So far, however, such topological polar structures have been observed only in superlattices grown on oxide substrates, which limits their applications in silicon-based electronics. Here we report the realization of room-temperature skyrmion-like polar nanodomains in lead titanate/strontium titanate bilayers transferred onto silicon. Moreover, an external electric field can reversibly switch these nanodomains into the other type of polar texture, which substantially modifies their resistive behaviours. The polar-configuration-modulated resistance is ascribed to the distinct band bending and charge carrier distribution in the core of the two types of polar texture. The integration of high-density (more than 200 gigabits per square inch) switchable skyrmion-like polar nanodomains on silicon may enable non-volatile memory applications using topological polar structures in oxides.

As with all stylish 2D functional materials, tellurene and tellurides possessing excellent physical and chemical properties such as high environmental stability, tunable narrow bandgap, and lower thermal conductivity, have aroused the great interest of the researchers. These properties of such materials also form the basis for relatively newfangled scholarly fields involving advanced topics, especially for broadband photodetectors. Integrating the excellent properties of many 2D materials, tellurene/telluride-based photodetectors show great flexibility, higher frequency response or faster time response, high signal-to-noise ratio, and so on, which make them leading the frontier of photodetector research. To fully understand the excellent properties of tellurene/tellurides and their optoelectronic applications, the recent advances in tellurene/telluride-based photodetectors are maximally summarized. Benefiting from the solid research in this field, the challenges and opportunities of tellurene/tellurides for future optoelectronic applications are also discussed in this review, which might provide possibilities for the realization of state-of-the-art high-performance tellurene/telluride-based devices.

Colorectal cancer (CRC) is one of the most heritable cancers, and genetic factors play an important role in the increased CRC risk. However, the well-established CRC-risk genes were limited for explaining the increased risk of CRC individuals. Germline mutations in DNA damage repair (DDR) genes have also been reported to be implicated in CRC heritability. Here, we aimed to determine the prevalence and significance of germline DDR and well-established CRC-risk gene variants in CRCs with paired somatic analyses. Next-generation sequencing (NGS) was performed on tumor tissues and paired white blood cells collected from 2160 Chinese patients with CRC using well-designed 381- or 733-cancer gene panel. Germline/somatic variations were identified and assessed for pathogenicity and likely pathogenicity. Of 2160 CRCs, 136 pathogenic germline mutations in 133 patients (133/2160, 6.1%) were identified in 21 genes, including 19 out of 32 examined DDR genes. Compared with non-carriers, individuals with germline variants were prone to a higher level of microsatellite instability (MSI) and tumor mutational burden (TMB), and an earlier age of onset. Somatic sequencing identified second hits in 24/133 (18%) patients with germline variants. Among the mismatch repair (MMR) genes with germline mutations, the second hit significantly increased MSI and TMB, particularly apparent in MSH6. All MMR germline variation carriers further with a second hit were all MSI-H and had an extraordinarily high level of TMB. Collectively, approximately 6.1% of CRC patients carried pathogenic germline variants, and additional somatic second hit increases the genomic instability in CRC, whereas the more clinical significance warrants further study.

Two-dimensional semiconductors could be used as a channel material in low-power transistors, but the deposition of high-quality, ultrathin high-κ dielectrics on such materials has proved challenging. In particular, atomic layer deposition typically leads to non-uniform nucleation and island formation, creating a porous dielectric layer that suffers from current leakage, particularly when the equivalent oxide thickness is small. Here, we report the atomic layer deposition of high-κ gate dielectrics on two-dimensional semiconductors using a monolayer molecular crystal as a seeding layer. The approach can be used to grow dielectrics with an equivalent oxide thickness of 1 nm on graphene, molybdenum disulfide (MoS2) and tungsten diselenide (WSe2). Compared with dielectrics created using established methods, our dielectrics exhibit a reduced roughness, density of interface states and leakage current, as well as an improved breakdown field. With the technique, we fabricate graphene radio-frequency transistors that operate at 60 GHz, and MoS2 and WSe2 complementary metal–oxide–semiconductor transistors with a supply voltage of 0.8 V and subthreshold swing down to 60 mV dec−1. We also create MoS2 transistors with a channel length of 20 nm, which exhibit an on/off ratio of over 107. Using a monolayer molecular crystal as a seeding layer, hafnium oxide dielectrics with an equivalent oxide thickness of only 1 nm can be deposited on graphene, molybdenum disulfide and tungsten diselenide.

Only a small series of studies has investigated primary tracheobronchial adenoid cystic carcinoma (TACC), and its prognosis and prognostic factors have not been well defined.Patients with TACC diagnosed histologically between January 1967 and December 2017 at our institution were retrospectively analyzed.A total of 191 consecutive patients were included in our study. One hundred sixty-three patients underwent surgery, while the remaining 28 patients received nonoperative therapy. The 5-year, 10-year, and 20-year survival rates of the surgical group were 85.00%, 63.40%, and 47.00%, while the 5-year and 10-year survival rates of the nonoperative group were 63.70% and 46.40%, respectively. The multivariate analysis showed that the complaint duration (7 months or ≥7 months) and treatment methods (R0 resection, R1 resection with radiotherapy, R1 resection without radiotherapy) were independent prognostic factors for disease-free survival of the R0/1 (resection with no residual tumor or microscopic residual tumor) resected patients, while the tumor size (≤3 cm or3 cm) and treatment methods were independent prognostic factors for the overall survival. Sixty-four (45.1%) patients in the R0/1 group experienced recurrence/progression, and compared with chemotherapy or supportive treatment, local treatment significantly improved the prognosis of these patients (P .050).The complaint duration and tumor size are independent prognostic factors for disease-free survival and overall survival in TACC, respectively. Complete resection of the primary tumor, postoperative adjuvant radiotherapy for patients with positive margins, and local treatment after postoperative recurrence or progression may contribute to better survival.

Background The systemic immune-inflammation index (SII) is correlated with patient survival in various types of solid tumors. However, only a few studies have focused on the prognostic value of the SII in patients with surgically resected non-small cell lung cancer (NSCLC). Methods This study was a single center retrospective analysis of 569 NSCLC patients who underwent curative lobectomy at the Department of Thoracic Surgery, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College between 2006 and 2012. A receiver operating characteristic curve was plotted to compare the discriminatory ability of the SII for overall survival (OS). A Cox proportional hazards regression model was used to perform univariate and multivariate analyses. Results The SII, neutrophil-lymphocyte ratio (NLR), and platelet-lymphocyte ratio (PLR) all correlated with OS in NSCLC patients, and the SII was an independent prognostic factor for OS (hazard ratio 1.256, 95% confidence interval 1.018-1.551; P = 0.034). The area under the receiver operating characteristic curve of the SII (0.547) was larger than the NLR (0.541) and PLR (0.531). Furthermore, the SII retained prognostic significance in the lung adenocarcinoma subgroup. Conclusion The SII is a promising prognostic predictor for patients with surgically resected NSCLC and retained prognostic significance in the lung adenocarcinoma subgroup. The prognostic value of the SII is superior to the NLR and PLR.

Due to the absence of dangling bonds, the integration of ultra-thin dielectric on 2D semiconductors has become a huge challenge, and its reliability research has been blank before. For the first time, we report the high $-\mathcal{K}$ dielectric reliability on Mos2. By PTCDA crystal as interface layer, we demonstrated excellent reliability of HfO 2 /PTCDA gate stack, including EBD over 8.9 MV/cm, $\mathrm{E}_{\text{BD}}\ ^{10\text{yrs}}$ over 6.5 MV/cm and ultra-low BD rate, all of which show better reliability than HfO 2 /Si.

Electron-boson interaction is fundamental to a thorough understanding of various exotic properties emerging in many-body physics. In photoemission spectroscopy, photoelectron emission due to photon absorption would trigger diverse collective excitations in solids, including the emergence of phonons, magnons, electron-hole pairs, and plasmons, which naturally provides a reliable pathway to study electron-boson couplings. While fingerprints of electron-phonon/-magnon interactions in this state-of-the-art technique have been well investigated, much less is known about electron-plasmon coupling, and direct observation of the band renormalization solely due to electron-plasmon interactions is extremely challenging. Here by utilizing integrated oxide molecular-beam epitaxy and angle-resolved photoemission spectroscopy, we discover the long sought-after pure electron-plasmon coupling-induced low-lying plasmonic-polaron replica bands in epitaxial semimetallic SrIrO$_3$ films, in which the characteristic low carrier concentration and narrow bandwidth combine to provide a unique platform where the electron-plasmon interaction can be investigated kinematically in photoemission spectroscopy. This finding enriches the forms of electron band normalization on collective modes in solids and demonstrates that, to obtain a complete understanding of the quasiparticle dynamics in 5d electron systems, the electron-plasmon interaction should be considered on equal footing with the acknowledged electron-electron interaction and spin-orbit coupling., 34 pages, 4 figures

Achieving high thermoelectric power factor in thin film heterostructures is essential for integrated and miniaturized thermoelectric device applications. In this work, we demonstrate a mechanism to enhance thermoelectric power factor through coupling the interfacial confined two-dimensional electron gas (2DEG) with thin film conductivity in a transition metal dichalcogenides-SrTiO3 heterostructure. Owing to the formed conductive interface with two-dimensional electron confinement effect and the elevated conductivity, the ZrTe2/SrTiO3 (STO) heterostructure presents enormous thermoelectric power factor as high as 4×10^5 μW cm^(-1) K^(-2) at 20 K and 4800 μW cm^(-1) K^(-2) at room temperature. Interfacial reaction induced degradation of Ti cations valence number from Ti4+ to Ti3+ is attributed to be responsible for the formation of the quasi-two-dimensional electrons at the interface which results in very large Seebeck coefficient; and the enhanced electrical conductivity is suggested to be originated from the charge transfer induced doping in the ZrTe2. By taking the thermal conductivity of STO substrate as a reference, the effective zT value of this heterostructure can reach 15 at 300 K. This superior thermoelectric property makes this heterostructure a promising candidate for future thermoelectric device, and more importantly, paves a new pathway to design promising high-performance thermoelectric systems.

Achieving high thermoelectric power factor in thin film heterostructures is essential for integrated and miniatured thermoelectric device applications. In this work, we demonstrate a mechanism and device performance of enhanced thermoelectric power factor through coupling the interfacial confined two-dimensional electron gas (2DEG) with thin film conductivity in a transition metal dichalcogenides-SrTiO3 heterostructure. Owing to the formed conductive interface with two-dimensional electron confinement effect and the elevated conductivity, the ZrTe2/SrTiO3 (STO) heterostructure presents enormous thermoelectric power factor as high as 4×10^5 μW/cmK^2 at 20 K and 4800 μW/cmK^2 at room temperature. Formation of quasi-two-dimensional electrons gas at the interface is attributed to the giant Seebeck coefficient, and enhanced electrical conductivity is suggested to be originated from charge transfer induced doping in the ZrTe2, which leads to extremely large thermoelectric power factor. By taking the thermal conductivity of STO substrate as a reference, the effective zT value of this heterostructure can reach 1.5 at 300 K. This high thermoelectric figure of merit is demonstrated by a prototype device based on this heterostructure which results in 3K temperature cooling by passing through a current of 100 mA. This superior thermoelectric property makes this heterostructure a promising candidate for future thermoelectric device, and more importantly, paves a new pathway to design promising high-performance thermoelectric systems.

2D semiconductors are considered to be one of the most promising channel materials to extend transistor scaling. However, the integration of ultra-thin dielectrics on 2D semiconductors has been challenging, and the reliability has not been investigated to date. Here, using monolayer 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) molecules as interface layer, we realize EOT as low as 1.7 nm on large-area monolayer CVD MoS 2 . The reliability of ultrathin high-κ dielectric on 2D semiconductors is systematically studied for the first time. The median breakdown (BD) field of HfO 2 /PTCDA stack is over 8.42 MV/cm, which is two times that of HfO 2 /Si under the same EOT. Through TDDB we project that the gate dielectric can work reliably for 10 years under E BD = 6.5 MV/cm, which shows 85% improvement than HfO 2 /Si. The BD current increase rate in our gate stack is several orders of magnitude smaller than HfO 2 /Si. The excellent reliability suggests that molecular interfacial layer is a promising dielectric technology for 2D electronics.

Layered metal chalcogenide materials provide a versatile platform to investigate emergent phenomena and two-dimensional (2D) superconductivity at/near the atomically thin limit. In particular, gate-induced interfacial superconductivity realized by the use of an electric-double-layer transistor (EDLT) has greatly extended the capability to electrically induce superconductivity in oxides, nitrides and transition metal chalcogenides and enable one to explore new physics, such as the Ising pairing mechanism. Exploiting gate-induced superconductivity in various materials can provide us with additional platforms to understand emergent interfacial superconductivity. Here, we report the discovery of gate-induced 2D superconductivity in layered 1T-SnSe2, a typical member of the main-group metal dichalcogenide (MDC) family, using an EDLT gating geometry. A superconducting transition temperature Tc around 3.9 K was demonstrated at the EDL interface. The 2D nature of the superconductivity therein was further confirmed based on 1) a 2D Tinkham description of the angle-dependent upper critical field, 2) the existence of a quantum creep state as well as a large ratio of the coherence length to the thickness of superconductivity. Interestingly, the in-plane approaching zero temperature was found to be 2-3 times higher than the Pauli limit, which might be related to an electric field-modulated spin-orbit interaction. Such results provide a new perspective to expand the material matrix available for gate-induced 2D superconductivity and the fundamental understanding of interfacial superconductivity., Comment: 18 pages, 4 figures, accepted by Nano Letters

Two-dimensional electron gas (2DEG) in SrTiO3 (STO)-based heterostructures has been a subject of intense scientific interest in recent years. In this work, the metallic transition metal dichalcogenides ZrTe2 was grown on STO by pulsed laser deposition and AlN was subsequently deposited as a protection layer. The high-resolution transmission electron microscopy and electron energy loss spectroscopy results demonstrated the system as a multilayer structure of AlN/ZrTe2/ZrO2/STO due to interface redox reactions and implied a conductive STO surface. The remarkable Shubnikov–de Haas oscillations detected by angular dependent magnetotransport measurements reveal clear evidence of a high mobility quasi-2DEG in the STO-based interface. Moreover, evidence for extra carriers with three-dimensional features is observed implying the multiband contributions, which provide an explanation for some anomalous behavior in STO-based heterostructures. In addition, the thickness dependence study suggests the charge transfer effect between the capping metallic topological material ZrTe2 and the interfacial 2DEG. This work provides insight into the intrinsic electronic structure of STO-based heterostructures, and the integrated systems can serve as a platform for studying the interplay of the 2DEG with attractive materials as well as developing practical device applications.

Dual targeting towards both extracellular and intracellular receptors specific to tumor is a significant approach for cancer diagnosis and therapy. In the present study, a novel nano-platform (AuNC-cRGD-Apt) with dual targeting function was initially established by conjugating gold nanocluster (AuNC) with cyclic RGD (cRGD) that is specific to αvβ3integrins over-expressed on the surface of tumor tissues and aptamer AS1411 (Apt) that is of high affinity to nucleolin over-expressed in the cytoplasm and nucleus of tumor cells. Then, AuNC-cRGD-Apt was further functionalized with near infrared (NIR) fluorescence dye (MPA), giving a NIR fluorescent dual-targeting probe AuNC-MPA-cRGD-Apt. AuNC-MPA-cRGD-Apt displays low cytotoxicity and favorable tumor-targeting capability at both in vitro and in vivo level, suggesting its clinical potential for tumor imaging. Additionally, Doxorubicin (DOX), a widely used clinical chemotherapeutic drug that kill cancer cells by intercalating DNA in cellular nucleus, was immobilized onto AuNC-cRGD-Apt forming a pro-drug, AuNC-DOX-cRGD-Apt. The enhanced tumor affinity, deep tumor penetration and improved anti-tumor activity of this pro-drug were demonstrated in different tumor cell lines, tumor spheroid and tumor-bearing mouse models. Results in this study suggest not only the prospect of non-toxic AuNC modified with two targeting ligands for tumor targeted imaging, but also confirm the promising future of dual targeting AuNC as a core for the design of prodrug in the field of cancer therapy.

Background: The systemic immune-inflammation index (SII) has been reported to be associated with patient survival in various kinds of solid tumors. However, just few studies have focused on its prognostic value in patients with surgically resected esophageal squamous cell carcinoma (ESCC). Materials and Methods: This study was a single-institution, retrospective analysis of 468 ESCC patients who underwent curative esophagectomy at the Department of Thoracic Surgery, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College between 2005 and 2008. The receiver operating curve (ROC) was plotted to compare the discrimination ability of the SII and other inflammatory factors for overall survival (OS) and disease-free survival (DFS). Univariate and multivariate analyses were performed based on the Cox proportional hazards regression model. Results: The SII, neutrophil-lymphocyte ratio (NLR), and platelet-lymphocyte ratio (PLR) were all associated with OS in ESCC patients. The SII, NLR, and PLR were independent prognostic factors for OS (hazard ratio (HR) = 1.604, 95% confidence interval (CI) 1.247-2.063, P < 0.001; HR = 1.396, 95% CI 1.074-1.815, P = 0.013; HR = 1.370, 95% CI 1.067-1.758, P = 0.013, respectively) and DFS (HR = 1.681, 95% CI 1.307-2.162, P < 0.001; HR = 1.376, 95% CI 1.059-1.788, P = 0.017; HR = 1.398, 95% CI 1.089-1.794, P = 0.009, respectively). The area under the curve (AUC) for SII was bigger than NLR, PLR, and MLR (0.553, 0.540, 0.532, and 0.521, respectively). Conclusion: The SII is a simple and promising prognostic predictor for patients with surgically resected ESCC. The prognostic value of SII is superior to those of the NLR, PLR and MLR. Moreover, the SII retained prognostic significance in stage I-II ESCC subgroup (OS, DFS) and stage III ESCC subgroup (DFS).

Two-dimensional (2D) materials such as graphene and transition-metal dichalcogenides reveal the electronic phases that emerge when a bulk crystal is reduced to a monolayer1-4. Transition-metal oxide perovskites host a variety of correlated electronic phases5-12, so similar behaviour in monolayer materials based on transition-metal oxide perovskites would open the door to a rich spectrum of exotic 2D correlated phases that have not yet been explored. Here we report the fabrication of freestanding perovskite films with high crystalline quality almost down to a single unit cell. Using a recently developed method based on water-soluble Sr3Al2O6 as the sacrificial buffer layer13,14 we synthesize freestanding SrTiO3 and BiFeO3 ultrathin films by reactive molecular beam epitaxy and transfer them to diverse substrates, in particular crystalline silicon wafers and holey carbon films. We find that freestanding BiFeO3 films exhibit unexpected and giant tetragonality and polarization when approaching the 2D limit. Our results demonstrate the absence of a critical thickness for stabilizing the crystalline order in the freestanding ultrathin oxide films. The ability to synthesize and transfer crystalline freestanding perovskite films without any thickness limitation onto any desired substrate creates opportunities for research into 2D correlated phases and interfacial phenomena that have not previously been technically possible.

In situ transmission electron microscopy (TEM) technology has become one of the fastest growing areas in TEM research in recent years. This technique allows researchers to investigate the dynamic response of materials to external stimuli inside the microscope. Optoelectronic functional semiconducting materials play an irreplaceable role in several key fields such as clean energy, communications, and pollution disposal. The ability to observe the dynamic behavior of these materials under real working conditions using advanced TEM technologies would provide an in-depth understanding of their working mechanisms, enabling further improvement of their properties. In this work, we designed a microelectromechanical-system-chip-based system to illuminate a sample inside a transmission electron microscope. This system allows simultaneous in situ optical and electrical measurements, which are crucial for optoelectronic semiconductor characterization.

Layered metal chalcogenide materials provide a versatile platform to investigate emergent phenomena and two-dimensional (2D) superconductivity at/near the atomically thin limit. In particular, gate-induced interfacial superconductivity realized by the use of an electric-double-layer transistor (EDLT) has greatly extended the capability to electrically induce superconductivity in oxides, nitrides, and transition metal chalcogenides and enable one to explore new physics, such as the Ising pairing mechanism. Exploiting gate-induced superconductivity in various materials can provide us with additional platforms to understand emergent interfacial superconductivity. Here, we report the discovery of gate-induced 2D superconductivity in layered 1T-SnSe

Van der Waals heterostructure based on layered two-dimensional (2D) materials offers unprecedented opportunities to create materials with atomic precision by design. By combining superior properties of each component, such heterostructure also provides possible solutions to address various challenges of the electronic devices, especially those with vertical multilayered structures. Here, we report the realization of robust memristors for the first time based on van der Waals heterostructure of fully layered 2D materials (graphene/MoS2-xOx/graphene) and demonstrate a good thermal stability lacking in traditional memristors. Such devices have shown excellent switching performance with endurance up to 107 and a record-high operating temperature up to 340oC. By combining in situ high-resolution TEM and STEM studies, we have shown that the MoS2-xOx switching layer, together with the graphene electrodes and their atomically sharp interfaces, are responsible for the observed thermal stability at elevated temperatures. A well-defined conduction channel and a switching mechanism based on the migration of oxygen ions were also revealed. In addition, the fully layered 2D materials offer a good mechanical flexibility for flexible electronic applications, manifested by our experimental demonstration of a good endurance against over 1000 bending cycles. Our results showcase a general and encouraging pathway toward engineering desired device properties by using 2D van der Waals heterostructures., To appear on Nature Electronics; 31 pages, 6 figures, 8 supplementary figures