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Ta doped TiN films were prepared on glass substrates by DC magnetron co-sputtering. The structure and properties of the obtained (Ti,Ta)N film were characterized by X-ray diffraction, Raman spectroscopy, ultraviolet/visible/near-infrared spectrophotometer and four probes method. The results show that with the increase of the sputtering power (PTa) for Ta target, the amount of Ta added to TiN lattice increases, resulting in a slight distortion of TiN lattice and stress transformation in the film. Correspondingly, the optical and electrical properties of the film changed. Raman spectrum was deconvoluted into five Lorentz peaks in the range of 50-1400 cm?1 and a new Raman peak appeared in all samples due to the substitution of Ta for Ti. The analysis of deconvolution results shows that the peak positions of different phonon modes and FWHM change, which may be related to the change of stress in the thin films caused by adding Ta to TiN lattice. The sample prepared with power of 50W has the maximum infrared emissivity of 1.35 and 0.43 at 2.5 and 25 ?m wavelengths, respectively, indicating that (Ti,Ta)N film is promising candidate for replacing TiN in Low-E glass.

Expansion of material is one of the major impediments in the high precision instrument and engineering field. Low/zero thermal expansion compounds have drawn great attention because of their important scientific significance and enormous application value. However, the realization of low thermal expansion over a wide temperature range is still scarce. In this study, a low thermal expansion over a wide temperature range has been observed in the Ta2WO8 oxide semiconductor. It is a balance effect of the negative thermal expansion of the a axis and the positive thermal expansion of the b axis and the c axis to achieve low thermal expansion behavior. The results of the means of variable temperature X-ray diffraction and variable pressure Raman spectroscopy analysis indicated that the transverse vibration of bridging oxygen atoms is the driving force, which is corresponding to the low-frequency lattice modes with a negative Gruneisen parameter. The present study provides one wide band gap semiconductor Ta2WO8 with anomalous thermal expansion behavior.

Oxygen vacancies have a profound effect on the electric, magnetic, and optical properties of transition-metal oxides, but their effect on thermal expansion properties has rarely been studied. Herei...

Toosendanin (TSN) is a triterpenoid extracted from the bark or fruits of Melia toosendan Sieb et Zucc, which is a traditional Chinese medicine and mainly grows in China and India. TSN has been verified to possess antitumor activities on various human cancers, whereas the effects of TSN on ovarian cancer (OC) has not been reported yet. Here, TSN was shown to significantly inhibit proliferation of SKOV3 and OVCAR3 cell lines in a dose- and time-dependent manner. Treatment of OC cells with TSN resulted in colony formation reduction, S and G2/M phase arrest, cell apoptosis, and dramatic decrease in mitochondrial membrane potential. Furthermore, TSN suppressed invasion and migration of OC cells. Research on molecular mechanism indicated that the above efficacy of TSN was associated with decreased expression of survivin, PARP-1, Bcl-2, Bcl-xl, caspase-3, caspase-9, MMP-2 and MMP-9 and increased expression of cleaved PARP-1, Bax, cleaved caspase-3 and cleaved caspase-9. Finally, in vivo results showed that TSN suppressed OC xenograft tumor growth by inducing apoptosis and regulating the related protein expression levels of SKOV3 cells in transplanted tumors. Taken together, our data provide new insights into TSN as a potentially effective reagent against human OC through caspase-dependent mitochondrial apoptotic pathway.

Nowadays, one of the most typical and important potential applications of negative thermal expansion (NTE) materials is to prepare zero thermal expansion or controllable coefficient thermal expansion materials by compounding them with positive thermal expansion materials. The research on NTE properties at the nanoscales is the basis and premise for the realization of high-quality composites. Here, using first-principles calculations, we take a typical open framework material ScF3 as an example to study a new NTE mechanism at the nanoscale, which involves edge and size effects, as well as crystal symmetry breaking. By analyzing the vibrational modes in ultrathin ScF3 films, three effects contributing to the NTE properties are identified, namely, the acoustic mode (ZA mode) induced by surface truncation, the enhanced rotations of ScF6 octahedra in the surface layer and the suppressed rotations of ScF6 octahedra in the inner layer due to crystal symmetry breaking. With increasing thickness, the effect of the ZA mode vibration gradually weakens, while the rotations of the ScF6 octahedra in the surface and inner layers are enhanced. Ultimately, the approximately mutual compensation of these three effects makes the NTE coefficients of different thicknesses almost unchanged. Finally, we simply generalize our conclusions to zero dimensional nanoparticles. This work reveals a new NTE mechanism in low-dimensional open framework materials, which serves as a guide in designing NTE materials at the nanoscale.

The chemical flexibility of A2M3O12-based compounds enables the design of materials with versatile functionalities such as ferroelastic switching, ion conduction and negative thermal expansion (NTE) above the ferroelastic transition temperature (Tt), which is promising for a variety of applications. Quantitative prediction of Tt is essential but lacking. Herein we propose a concept of averaged effective electronegativity (AEE) and establish a linear relationship between the Tt and AEE for A2M3O12-based compounds. The linear scaling law is validated using first principles calculations of the effective charge on oxygen and its effectiveness is verified experimentally by designing high entropy compounds Scx1Zrx2Hfx3Fex4Moy1Vy2O12 and a NTE compound Zr2MoVPO12 with expected Tt. Generalization of the linear scaling law to other NTE oxides with displacive phase transition is also demonstrated. The findings can be used as a simple and effective approach to guide the design of novel compounds with desired properties and Tt.

A large negative thermal expansion (NTE) (α

Understanding the role of guest molecules in the lattice void of open-framework structures is vital for tailoring thermal expansion. Here, we take a new negative thermal expansion (NTE) compound, T...

Exploring isotropic negative thermal expansion (NTE) compounds is interesting, but remains challenging. Here, a new concept of "average atomic volume" is proposed to find new NTE open-framework materials. According to this guidance, two NTE compounds, AgB(CN)4 and CuB(CN)4, have been discovered, of which AgB(CN)4 exhibits a large NTE over a wide temperature range (αv = -40 × 10-6 K-1, 100-600 K). The analysis by extended X-ray absorption fine structure spectroscopy and first-principles calculation indicate that (i) the NTE driving force comes from the transverse vibrations of bridge chain atoms of C and N, corresponding to the low-frequency phonon modes; and (ii) the same transverse vibration direction of C and N atoms is a key factor for the occurrence of strong NTE in AgB(CN)4. The present concept of "average atomic volume" can be a simple parameter to explore new NTE compounds especially in those open-framework materials.

Perovskite Er1-xCaxMnO3 (x = 0, 0.1, 0.2, 0.25, 0.3, 0.4, 0.5) was synthesized using a solid-state method. Thermal expansion behavior was tested using a thermal dilatometer and high-temperature X-ray diffraction (XRD). The experimental results indicated the doping contents of Ca (x) in the Er1-xCaxMnO3 have a dramatic effect on their thermal expansion behavior. The samples of Er1-xCaxMnO3 (x = 0.1,0.2 and 0.25) exhibit positive thermal expansion (PTE) characteristics while Er0.7Ca0.3MnO3 (x = 0.3) exhibits a negative thermal expansion (NTE) property with a thermal expansion coefficient of −3.1 × 10−6 K−1 in room temperature (RT) −750 K. In addition, Er0.6Ca0.4MnO3 (x = 0.4) exhibits NTE properties only at RT–500 K, and Er0.5Ca0.5MnO3 (x = 0.5) exhibits PTE properties at RT–750 K. The thermal shrinkage mechanism is the Jahn–Teller effect of the Mn3+ ions and the double exchange of Mn3+–O–Mn4+ in Er0.7Ca0.3MnO3. This phenomenon causes Mn–O octahedral distortion and oxygen vacancy, causing Er0.7Ca0.3MnO3 to become anisotropic. This feature results in the elastic deformation of Er0.7Ca0.3MnO3 during heating, which consumes the void and displays NTE at macro level.

A2M3O12-based materials have received considerable attention owing to their wide range of negative thermal expansion (NTE) and chemical flexibility toward novel materials design. However, the struc...

Negative thermal expansion (NTE) behaviors have been observed in various types of compounds. The achievement in the merits of promising low-cost and facile NTE oxides remains challenging. In the pr...

Designing negative thermal expansion (NTE) materials with a larger NTE coefficient and a wider temperature window is a great challenge nowadays, leading to the limitation of existing NTE materials such that only about 150 kinds of NTE materials have been discovered since 1996. Here, using first-principles calculations combined with the quasi-harmonic approximation (QHA), we find that the synergistic effect of different vibrational modes can significantly enhance the NTE in open framework compounds. We systematically investigate the NTE properties of the M2IIMIV(CN)8 (MII = Ni, Co, Fe, and Mn; MIV = Mo and W) family, which is the first kind of Prussian blue analogues (PBAs) with a 2D and 3D topology structure, to explore the synergistic enhancement effect in NTE. We reveal that both the optical modes of the rotational motion of [W(CN)8] and [Ni(NC)4] rigid units and the low frequency acoustic modes of the transverse vibration contribute significantly to the NTE. Furthermore, the coefficients of NTE increase monotonously with increasing ionic radius upon substituting Ni in M2IIW(CN)8 with Co, Fe, or Mn, respectively. Analyzing the vibrational modes of the substituted systems indicates that the dramatic changes in NTE originate from a highly synergistic effect, in which all the frequencies of these NTE modes have the same trend, i.e. the lower the frequencies, the larger the coefficient of NTE. This work clearly presents a synergistic mechanism of enhancing NTE in PBA materials, and sheds light on designing new materials with better properties.

HfMgW3O12 is a representative material with negative thermal expansion in the ABM3O12 (A = Zr, Hf; B = Mg, Mn, Zn, M = W, Mo) family. Herein we report a novel feature of hydration in HfMgW3O12 and its effect on the thermal expansion and its structures which have not been determined previously. It is found that hydrate formation in HfMgW3O12 occurs under ambient or moisture conditions and restrain the low energy librational and translational and even high energy bending and stretching motions of the polyhedra. The coefficient of thermal expansion could be tailored from negative to zero and positive depending on the hydration levels. The unhydrated HfMgW3O12 adopts an orthorhombic structure with space group Pna21 (33) without phase transition at least from 80 K to 573 K, but pressure-induced structure transition and amorphization are found to occur at about 0.19 Gpa and above 3.93 GPa, respectively.

The control of thermal expansion is essential in applications where thermal stability is required from fiber optics coatings, high performance fuel cell cathodes to tooth fillings. Negative thermal expansion (NTE) materials, although rare, are fundamental for this purpose. This work focuses on studying tetracyanidoborate salt CuB(CN)4, an interesting cubic-structure material that displays large isotropic NTE. A joint study of synchrotron x-ray diffraction, temperature-dependent Raman spectroscopy, and lattice dynamics calculations was conducted, showing that not only low-frequency optical modes (transverse thermal vibrations of N and C atoms) but also the acoustic modes (the vibrations of Cu atoms as a collective torsion of the neighboring atoms), contribute to NTE. As a result, new insights were gained into the NTE mechanism of CuB(CN)4 and related framework materials.

The chemical flexibility of A

Nowadays, one of the most typical and important potential applications of negative thermal expansion (NTE) materials is to prepare zero thermal expansion or controllable coefficient thermal expansion materials by compounding them with positive thermal expansion materials. The research on NTE properties at the nanoscales is the basis and premise for the realization of high-quality composites. Here, using first-principles calculations, we take a typical open framework material ScF

Macrophage-targeting therapies have become attractive strategies for immunotherapy. Deficiency of MARCO significantly inhibits tumor progression and metastasis in murine models of pancreatic cancer. However, the role of MARCO in patients with pancreatic cancer remains unclear. In the present study, we analyzed tumor-associated macrophage (TAM)-related changes using the Cancer Genome Atlas database. We observed a significant enrichment of M2 macrophages in pancreatic cancer tissues. We found that several pro-tumor markers are increased in cancer tissues, including CD163, CD206, SIRPα, LILRB1, SIGLEC10, AXL, MERTK, and MARCO. Crucially, MARCO is highly or exclusively expressed in pancreatic cancer across many types of solid tumors, suggesting its significant role in pancreatic cancer. Next, we investigated the expression of MARCO in relation to the macrophage marker CD163 in a treatment-naïve pancreatic cancer cohort after surgery (n = 65). MARCO and CD163 were analyzed using immunohistochemistry. We observed increased expression of CD163 and MARCO in pancreatic cancer tissues compared with paracancerous tissues. Furthermore, we observed a large variation in CD163 and MARCO expression in pancreatic cancer tissues among cases, suggesting the heterogeneous expression of these two markers among patients. Correlation to clinical data indicated a strong trend toward worse survival for patients with high CD163 and MARCO macrophage infiltration. Moreover, high CD163 and MARCO expression negatively affected the disease-free survival and overall survival rates of patients with pancreatic cancer. Univariate and multivariate analysis revealed that CD163 and MARCO expression was an independent indicator of pancreatic cancer prognosis. In conclusion, high CD163 and MARCO expression in cancer tissues is a negative prognostic marker for pancreatic cancer after surgery. Furthermore, anti-MARCO may be a novel therapy that is worth studying in depth.

Negative thermal expansion (NTE) of materials is an intriguing phenomenon challenging the concept of traditional lattice dynamics and of importance for a variety of applications. Progresses in this field develop markedly and update continuously our knowledge on the NTE behavior of materials. In this article, we review the most recent understandings on the underlying mechanisms (anharmonic phonon vibration, magnetovolume effect, ferroelectrorestriction and charge transfer) of thermal shrinkage and the development of NTE materials under each mechanism from both the theoretical and experimental aspects. Besides the low frequency optical phonons which are usually accepted as the origins of NTE in framework structures, NTE driven by acoustic phonons and the interplay between anisotropic elasticity and phonons are stressed. Based on the data documented, some problems affecting applications of NTE materials are discussed and strategies for discovering and design novel framework structured NET materials are also presented.

The control of thermal expansion is attractive but remains challenging for the studies of negative thermal expansion materials. Here, we report a continuously controllable thermal expansion from negative to positive by means of adjusting the magnetic moment of Fe in Er2(Fe,Co)14B intermetallic compounds. Interestingly, a zero thermal expansion (ZTE) has been achieved in a wide temperature range (ΔT = 355 K), which is larger than most existing ZTE alloys. The spontaneous magnetostriction (ωS) reveals a negative contribution arising from the magneto-volume effect to the controllable thermal expansion. The present study could be suitable for the design of controllable thermal expansion of other alloys related to the magneto-volume effect.

Negative thermal expansion (NTE) behavior is an interesting physical phenomenon, but the number of NTE materials is limited. In this study, a new NTE compound has been found, FeFe(CN)6 Prussian blue analogue, where the average linear coefficient of thermal expansion (αl) is −4.260 × 10−6 K−1 between 100 and 450 K. The NTE properties and local vibration dynamics have been investigated by joint experiments of synchrotron X-ray diffraction, X-ray pair distribution function, and extended X-ray absorption fine structure spectroscopy. It has been observed that the Fe–C/Fe–N bonds expand with increasing temperature, while the unit cell shrinks in FeFe(CN)6. The vibration directions of both Fe–C and Fe–N prefer to be perpendicular to the linkage of Fe–CN–Fe rather than being parallel. More pieces of evidence indicate that the transverse vibrations of N atoms dominate the NTE behavior of FeFe(CN)6. The present results prove directly that the transverse thermal vibrations of C and N atoms are crucial for the occurrence of the NTE of Prussian blue analogues.

Germanium diselenide (GeSe2) is a promising candidate for electronic devices because of its unique crystal structure and optoelectronic properties. However, the evolution of lattice and electronic structure of β-GeSe2 at high pressure is still uncertain. Here we prepared high-quality β-GeSe2 single crystals by chemical vapor transfer (CVT) technique and performed systematic experimental studies on the evolution of lattice structure and bandgap of β-GeSe2 under pressure. High-precision high-pressure ultra low frequency (ULF) Raman scattering and synchrotron angle-dispersive x-ray diffraction (ADXRD) measurements support that no structural phase transition exists under high pressure up to 13.80 GPa, but the structure of β-GeSe2 turns into a disordered state near 6.91 GPa and gradually becomes amorphous forming an irreversibly amorphous crystal at 13.80 GPa. Two Raman modes keep softening abnormally upon pressure. The bandgap of β-GeSe2 reduced linearly from 2.59 eV to 1.65 eV under pressure with a detectable narrowing of 36.5%, and the sample under pressure performs the piezochromism phenomenon. The bandgap after decompression is smaller than that in the atmospheric pressure environment, which is caused by incomplete recrystallization. These results enrich the insight into the structural and optical properties of β-GeSe2 and demonstrate the potential of pressure in modulating the material properties of two-dimensional (2D) Ge-based binary material.

BackgroundPrimary liver cancer is a common clinical malignancy. Traditional Chinese medicine (TCM) is an alternative treatment for primary liver cancer. TCM effectively improves the survival rate and quality of life of patients, but high-level evidence is lacking.Patients and methodsThis study determined whether the combination of TCM and conventional cancer treatment affects the survival of liver cancer patients. Patients were selected from 5 tertiary hospitals in Henan Province. Two thousand and sixty-seven patients with primary liver cancer were included in the study for analysis. Patients who received adjunctive TCM treatment and underwent treatment for more than 1 month were classified as the TCM intervention cohort, i.e., the exposure group. Patients who did not receive adjunctive TCM treatment or who received adjunctive TCM treatment for less than 1 month were classified as the non-TCM intervention cohort, i.e., the non-exposed group. The main outcome indicators were the survival outcome and survival time of primary liver cancer patients. The propensity score inverse probability weighting method was used to balance the differences in the observed characteristics between the groups.ResultsThe primary cohort comprised 2,067 patients with primary liver cancer, including 462 patients who received adjunctive TCM treatment and 1,605 patients who did not receive adjunctive TCM treatment. Multiple logistic (binary) regression analysis results showed that adjunctive TCM treatment may reduce the mortality of primary liver cancer patients (regression coefficient = −0.82, PP

Objective: To systematically access the efficacy and safety of ICIs monotherapy or ICIs combined with chemotherapy versus chemotherapy in advanced gastrointestinal cancers. Methods: Retrieved the randomized controlled trials (RCTs) of ICIs or ICIs combined with chemotherapy and chemotherapy in advanced gastrointestinal tumors included in PubMed, Cochrane Library, Embase, and Web of sciences. Meta-analysis was performed using Review Manager 5.3 software. The primary outcomes are overall survival (OS) and progression-free survival (PFS), and secondary outcomes include objective response rate (ORR) and adverse events (AEs).Results: A total of 13 RCTs including 5166 patients with advanced gastrointestinal tumors were included in this meta-analyses. ICIs or ICIs combined with chemotherapy exhibited superior OS (HR: 0.84, 95% CI: 0.76-0.94, P=0.001) compared with chemotherapy. Subgroup analysis shows that the use of anti-PD-1 antibodies significantly benefits OS (HR:0.80, 95%CI:0.70-0.91, P=0.0009). The second-line application of ICIs or ICIs combined with chemotherapy will have more significant OS benefits than chemotherapy ( HR: 0.85, 95%CI: 0.79-0.97, P=0.01). No significant difference was observed in PFS and ORR. The PFS of squamous cell carcinoma seemed to be better (HR:0.72, 95%CI:0.60-0.87, P=0.0005). No significant difference in AEs and grade≥3 AEs. But the incidence of AEs decreased when ICIs monotherapy (RR:0.81, 95%CI:0.66-0.99, P=0.04).Conclusion: For gastrointestinal malignant tumors, patients who received ICIs or ICIs combined with chemotherapy had a superior OS compared with chemotherapy, not at the cost of increased AEs, the proportion of AEs is reduced than chemotherapy while ICIs monotherapy. PFS and ORR are not significantly improved.

Zn

面对高精尖仪器或设备的热膨胀控制的需求, 探索新的负热膨胀材料显得尤为重要. 本文采用“平均原子晶格体积”概念预测各向异性新的负热膨胀材料体系, 据此发现了REFe(CN)6 (RE = La, Sm, Ho,Lu) 负热膨胀材料家族. 我们采用原位中子粉末衍射(NPD)、X射线吸收精细结构谱(EXAFS)和第一性原理计算揭示了其负热膨胀来源于低频声子振动模式中的CN原子的横向热振动, 进一步发现“平均原子晶格体积”越大, 其对应的低频声子模式频率越低, 格林艾森常数越负,CN原子的横向热振动越强. 本工作为定性预测负热膨胀材料提供了新的方法, 对热膨胀控制与设计具有重要意义.

Zn2GeO4 is a multifunctional material whose intrinsic thermal expansion properties below ambient temperature have not been explored until now. Herein, the thermal expansion of Zn2GeO4 is investigat...