This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief. There were serious questions about the validity of the data contained in these articles: " … the Western blot bands in … papers are all very regularly spaced and have a smooth appearance in the shape of a dumbbell or tadpole, without any of the usual smudges or stains. All bands are placed on similar looking backgrounds, suggesting they were copy/pasted from other sources, or computer generated". Based on the latter findings, the Editor-in-Chief requested the authors to provide the raw data. However, the authors were not willing and/or able to fulfil this request and therefore the Editor-in-Chief decided to retract the article. As a consequence the writing in this article misled and deceived reviewers and readers of the journal and thus as a whole represents a gross misuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.

Background: Roquin2 is an important RNA-binding protein that destabilizes the mRNA of many inflammatory cytokines, such as TNF, IL6 and PTGS2, which are also important angiogenic factors. However, the potential role of Roquin2 in breast tumor angiogenesis and cancer progression remains unclear.Methods: The public breast cancer dataset, real-time Polymerase Chain Reaction and Western blot were used to detect the expression of Roquin2 in human breast cancer tissues and cells. RNA-sequencing and PCRarray were used to determine the effect of Roquin2 on the expression of angiogenesis-related genes in the tumor cells. The effects of Roquin2 on tumor angiogenesis were evaluated by in vitro and in vivo experiments. RNA immunoprecipitation assay, luciferase reporter assay, RNA-EMSA, and RIP-ChIP were used to elucidate the potential molecular mechanism of Roquin2.Findings: Roquin2 expression was repressed in breast cancer tissues and strongly associated with patient poor survival. Overexpression of Roquin2 inhibited tumor angiogenesis in vitro and in vivo, whereas its further knockdown promoted it. Mechanistically, Roquin2 specifically destabilizes the proangiogenic genes, including endoglin, endothelin-1, vascular endothelial growth factor B and platelet derived growth factor C, by directly interacting with the stem–loop structure in the 3' untranslated region (3'UTR) of these mRNAs through its ROQ domain, thereby modulating the balance of angiogenesis-related genes expression program.Interpretation: Our results demonstrate that Roquin2 is a novel tumor suppressor in breast cancer that inhibits tumor angiogenesis by specifically downregulating the expression of multiple proangiogenic genes, and thus might provide a potential anti-angiogenic therapeutic target for breast cancer.Funding: This work was supported by grants from the National Natural Science Foundation of China (NSFC) (Grant Number: 81702769), CAMS Innovation Fund for Medical Science (No. 2017-I2M-1-016), and the PUMC Youth Fund (Grant Number: 3332017105).Declaration of Interest: The authors declare no conflict of interest.Ethical Approval: The study was conducted in accordance with the Declaration of Helsinki, and the experimental protocols were approved by the Ethics Committee of Beijing Jishuitan Hospatial, the 4th Clinical Medical College of Peking University and the Medical Ethics Committee of the Institute of Microcirculation, CAMS & PUMC.

Micro/nanorobots have been extensively explored as a tetherless small-scale robotic biodevice to perform minimally invasive interventions in hard-to-reach regions. Despite the emergence of versatile micro/nanorobots in recent years, matched in vivo development remains challenging, limited by unsatisfactory integration of core functions. Herein, we report a polydopamine (PDA)-coated magnetic microswimmer consisting of a magnetized Spirulina (MSP) matrix and PDA surface. Apart from the properties of the existing MSP (e.g., robust propulsion, natural fluorescence, tailored biodegradation, and selective cytotoxicity), the introduced PDA coating enhances the photoacoustic (PA) signal and photothermal effect of the MSP, thus making PA image tracking and photothermal therapy possible. Meanwhile, the PDA’s innate fluorescence quenching and diverse surface reactivity allows an off–on fluorescence diagnosis with fluorescence probes (e.g., coumarin 7). As a proof of concept, real-time image tracking (by PA imaging) and desired theranostic capabilities of PDA-MSP microswimmer swarms are demonstrated for the treatment of pathogenic bacterial infection. Our study suggests a feasible antibacterial microrobot for in vivo development and a facile yet versatile functionalization strategy of micro/nanorobots.

In the current research work, safranine T (ST) was chosen to be the guest, and the preparation of carbon dots (CDs) was done by a one-step hydrothermal methodology with citric acid (CA) to be the precursor, besides the surface passivation species in the consequent host-guest CDs. In addition, the CDs that had high-luminescence properties were prepared in the solid and liquid states, respectable fluorescence quantum yield of 15.2% (liquid) and 39.9% (solid), which is higher as compared with the majority of the reported orange fluorescent CDs. Meanwhile, red light-emitting diodes (LEDs) were fabricated with the use of a combination of CDs and UV LED chips. The constructed white LEDs possess excellent white light properties with the Commission Internationale de L'Eclairage chromaticity coordinate of (0.33, 0.34), coupled with the normal correlated color temperature of 5347 K as well as elevated color rendering index of 81 (>80), which seems appropriate for indoor lighting. Moreover, vitamine B12 (VB12) has the potential of productively quenching the fluorescence of CDs on the basis of the inner filter effect. Besides that, the system possessed the elevated selectivity with regard to VB12 that had the detection limit of 60.78 nM, which could further have been illustrated in not just VB12 tablets but in vitamin drink and human serum samples as well. Moreover, the CDs with the positive biocompatibility as well as ignorable cytotoxicity were extended for sensing VB12 in the living cell. These properties suggest that CDs have immense potential in the field of sensors, cell imaging, and optical devices.

Misfit dislocation pattern is generally accepted to play a critical role on the interface mediated deformation mechanism such as dislocation nucleation and shear sliding in various flat interfaces, however, a specific mechanical loading may dynamically modify its distribution and character before the appearance of distinct plastic flow out of interfaces. Taking bimetal semi-coherent interfaces with high symmetrically distributed misfit dislocations as an illustration, we reveal for the first time that the dynamic evolution of misfit dislocation patterns in interface appears for some specific interface types and loading schemes, and eventually governs the preferred sites of dislocation nucleation and the shear sliding mechanism. In contrary to the nearly unchanged feature of misfit dislocations under biaxial in-plane tension, the initial patterns around nodes of misfit dislocations are found to be distorted and spread anisotropically within interface during uniaxial in-plane loading, which in turn governs the non-Schmid phenomena of dislocation nucleation. A similar dependence of shear sliding mechanism on the anisotropic feature of core spreading of misfit dislocations in interface is also observed, depending on the characteristic of misfit dislocation patterns. Further investigations suggest that the dynamic evolution of misfit dislocation patterns may differ substantially for different types of interfaces, and consequently contribute to different mechanisms of dislocation nucleation and shear sliding. These results suggest a necessity to investigate the dynamic evolution of misfit dislocation patterns to get a more realistic understanding on the interface dominated plasticity.

The dynamic mechanical relaxation of metallic glasses is closely associated with the physical and mechanical properties. In the current work, the dynamic mechanical relaxation behaviors of Cu46Zr45Al7Y2 and La65Al14(Cu5/6Ag1/6)11(Ni1/2Co1/2)10 bulk metallic glasses are investigated by mechanical spectroscopy. In general, metallic glasses display two relaxation modes: main (α) relaxation and the slow secondary (β) relaxation. The α relaxation is linked to the dynamic glass transition phenomenon and viscous flow while the slow β relaxation is associated with many fundamental issues, such as diffusion and glass transition phenomenon. The experimental study shows La65Al14(Cu5/6Ag1/6)11(Ni1/2Co1/2)10 bulk metallic glass displays a noticeable slow β relaxation. Contrarily, the Cu46Zr45Al7Y2 bulk metallic glass relaxation process takes the form of an "excess wing". In the framework of quasi-point defects (QPD) theory, the dynamic mechanical response of the metallic glasses is discussed.

Hypoxia-inducible factor-1α (HIF-1α) is considered the main transcriptional regulator of the hypoxia-specific cellular and developmental response. This study was performed to investigate the effect of Shenqin biochemical extract (SQBE) on HIF-1α expression in ultraviolet B (UVB)-irradiated HaCaT cells and the possible action mechanisms of SQBE against UVB-induced skin cancer. HaCaT cells in logarithmic growth phase were seeded in Dulbecco's modified Eagle's medium with 10% fetal bovine serum, and conventionally cultured at 37°C with 5% CO2. Cells were divided into control group (administered the same amounts of dimethyl sulfoxide), SQBE1 group (12.5 μg/mL SQBE), SQBE2 group (25.0 μg/mL SQBE), and SQBE3 group (50.0 μg/mL SQBE). Four hours post administration, the control and treatment groups were irradiated with UVB (0, 20, 40, and 60 mJ/cm2). After 24 h, cell survival rate was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Expression levels of HIF-1α mRNA and protein were detected by polymerase chain reaction and western blotting, respectively. SQBE-treated, UVB-irradiated cells had improved survival rates. This increase was most significant in SQBE3 group (P < 0.01), which also had effectively reduced expression of intracellular HIF-1α mRNA and protein. Hence, SQBE had a protective effect on UVB-irradiated HaCaT cells and inhibited the UVB irradiation-induced expression of HIF-1α. This indicates that SQBE could prevent the occurrence of UVB radiation-induced skin cancer.

Objective: To compare the mortality, survival rate and the therapeutic efficacy between mitral valve repair and replacement as treatment for severe ischemic mitral regurgitation (IMR), and explore the middle- and long-term outcomes. Methods: Between January 2000 and January 2016, 378 patients with severe IMR underwent coronary artery bypass grafting (CABG) combined with mitral valve repair (n=162) or mitral valve replacement (n=216) in the Department of Cardiovascular Surgery of Nanjing First Hospital. Clinical data, in-hospital morbidity and mortality of patients were retrospectively reviewed. The patients were followed up for the long term survival rate, heart function and re-admission. Results: No statistically significant differences of baseline data and operation details were found between the two groups except for left ventricular end-diastolic diameter[(61.3±10.2)mm in replacement group vs (56.2±9.0)mm in repair group, P<0.001]. Seven patients died during the perioperative period, with a total operation mortality of 1.9%.No significant difference of mortality was found between the two groups (5 cases in the replacement group and 2 cases in the repair group). The early outcome after the surgery showed that the rate of low cardiac output and ventricular arrhythmia of patients were significantly higher in the replacement group compared with the repair group (both P<0.05). The mortality of patients received mitral valve replacement was better than who received mitral valve repair when left ventricular end-diastolic diameter was over 65 mm (5.9% vs 10.0%, P=0.036). No significant differences were observed between the two groups in the middle- and -long term survival rate (87% for replacement group vs 85% for repair group, P=0.568). The follow-up time was 1-85 (52.8±21.5) months and the follow-up rate was 93%. The rate of valve-related complications was significantly higher in the repair group compared with the replacement group (8.82% vs 3.82%, P=0.003). Conclusions: We should choose the surgical methods carefully (replacement or repair) for severe IMR patients according to degree of left ventricular remodeling and pathological changes of mitral valve. Mitral valve replacement with preservation of the subvalvular apparatus is a safe and effective surgical alternative for mitral valve repair, especially for patients with complications or complex reflux.

Using atomistic simulations, several semi-coherent cube-on-cube bimetal interfaces are comparatively investigated to unravel the combined effect of the character of misfit dislocations, the stacking fault energy difference between bimetal pairs, and their lattice mismatch on the dissociation of interfacial misfit dislocations. Different dissociation paths and features under loadings provide several unique deformation mechanisms that are critical for understanding interface strengthening. In particular, applied strains can cause either the formation of global interface coherency by the migration of misfit dislocations from an interface to an adjoining crystal interior or to an alternate packing of stacking faults connected by stair-rod dislocations.

The structure of A-C type intervariant interface in nonmodulated martensite in the Ni54Mn25Ga21 alloy was studied using high resolution transmission electron microscopy. The A-C interface is between the martensitic variants A and C, each of which has a nanoscale substructure of twin-related lamellae. According to their different thicknesses, the nanoscale lamellae in each variant can be classified into major and minor lamellae. It is the boundaries between these lamellae in different variants that constitute the A-C interface, which is thus composed of major-major, minor-minor, and major-minor lamellar boundaries. The volume fraction of the minor lamellae, λ, plays an important role in the structure of A-C interfaces. For major-major and minor-minor lamellar boundaries, they are symmetrical or asymmetrical tilt boundaries; for major-minor boundary, as λ increases, it changes from a symmetrical tilt boundary to two asymmetrical microfacets. Moreover, both lattice and misfit dislocations were observed in the A-C interfaces. On the basis of experimental observations and dislocation theory, we explain how different morphologies of the A-C interface are formed and describe the formation process of the A-C interfaces from λ ≈ 0 to λ ≈ 0.5 in terms of dislocation-boundary interaction, and we infer that low density of interfacial dislocations would lead to high mobility of the A-C interface.

Surface mechanical grinding of a Ni-based superalloy can introduce a gradient microstructure in the surface layer with a grain size from nanoscale to microscale. In-depth investigation of the crystal orientation distribution of the surface nanostructured layer is more often, however, not an easy work by using the scanning electron microscope (SEM) based electron backscatter diffraction (EBSD) method due to its sensitivity to lattice distortions and spatial resolution limitation. Here we use a newly developed precession electron diffraction (PED) technique coupled with transmission electron microscopy (TEM) to investigate the microstructural and crystallographic characteristics of the surface gradient nanostructure, with particular emphasis on the topmost nanocrystalline layer. A strong shear texture and a minor Copper texture were identified according to orientation analyses of the 1.6 mu m thick near-surface nanocrystalline layer. The PED technique is proved to be practical for two dimensional orientation mapping of severely deformed microstructures at the nanoscale.

In this paper, the effect of surfactant polyvinylalcohol (PVA) and polyacrylate acid (PAA) on shape evolution of Pb(Zr0.3Ti0.7)O3 (PZT) nano materials synthesized by hydrothermal method was studied. PZT nanorod array was grown on the conduction substrate surface of (100) Nb–SrTiO3 with optimized PVA and PAA concentrations. X-ray diffraction, scanning electron microscopy and transmission electron microscopy were used to characterize the PZT nanomaterials. The results demonstrated that the optimization concentration of PVA and PAA were 0.8 and 3.2 g L−1, respectively. The pyroelectric coefficient of the PZT nanorod array was 1.75 × 10−9 C cm−2 K−1 before poling and 2.56 × 10−9 C cm−2 K−1 after poling. This low temperature synthesized PZT nanorod array shows great potential application in pyroelectric nanodevices.

7050 Al alloy was successfully processed by equal-channel angular pressing (ECAP) at room temperature (RT). The effect of ECAP on the subsequent aging precipitation behavior was investigated by using transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). The results reveal that the kinds, spatial distribution and sizes of precipitates in the unECAPed and the ECAPed samples are different. ECAP accelerates the process of aging precipitation and results in the broadening of precipitate size distribution. ECAP can produce not only deformation heat but also internal defects such as excess vacancies and high density of dislocations when the sample passes through the main deformation zone. Deformation heat can lead to pre-precipitation, forming a small amount of GPII zones during ECAP processing. Strain-induced excess vacancies make solute segregation along dislocations by the mechanism of nonequilibrium segregation. High density dislocations mainly accelerate the process of aging precipitation. Besides, dislocations also induce the competition between homogeneous precipitation and heterogeneous precipitation on dislocations due to the flow of solutes and vacancies towards dislocations.

The interfacial reactions of B4C-coated and C-coated SiC fiber reinforced Ti-43Al-9V composites were investigated by scanning electron microscope and transmission electron microscope. The detailed mi- crostructures as well as the chemical composition throughout the reaction zone were identified. For SiCf B4C/TiAl composite, the reaction zone from B4C coating to TiAl matrix is composed of 4 layers, namely, a carbon-rich layer, a mixed layer of TiB2 + amorphous carbon, a TiC layer and a mixed layer of TiB + Ti2AlC. For SiCf/C/TiAl composite, the reaction zone from C coating to TiAl matrix is composed of 3 layers, namely, a fine-grained TiC layer, a coarse-grained TiC layer and a thick Ti2AlC layer. For both kinds of composites, the reaction mechanisms of the interfacial reactions were analyzed, and the corresponding reaction kinetics were calculated. The activation energies of interfacial reaction in SiCf/B4C/TiAl composite and SiCf/B4C/TiAl composite are 308.1 kJ/mol and 230.7 kJ/mol, respectively. (C) 2014 Elsevier Ltd. All rights reserved.

The deformation and fracture process in Al–Cu–Mg alloy were investigated by using the in situ straining transmission electron microscopy (TEM) method. Some major aspects of the fracture process, including dislocation emission and migration, thinning of dislocation free zone (DFZ), crack propagation (both in continuous and discontinuous manners) and slipping/twinning deformation, can be observed. The rod-like T dispersoids, which may increase the microcrack initiation sensitivity, also can effectively prevent the fast and continuous propagation of the crack. DFZ ahead of crack tip can be thinned in a mixed mode characterized by tearing and shear deformation, while nanovoids, which are typical characteristics in DFZ during discontinuous crack propagation, may originate from the enrichment of defects such as dislocations and vacancies. Deformation twinning at crack tip can slow down crack propagation and change crack propagation path, thus may be beneficial to the fracture toughness of the alloy.

The substructures in rotation-twinned T (Al20Cu2Mn3) particles were investigated by means of high resolution transmission electron microscopy (HRTEM) and high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) in the present work. A flattened hexagonal structural subunit with 20 atomic columns was proposed. The stacking mode of these subunits in non-defective T phase was proved to be tessellation of many flattened hexagonal subunits with the same orientations, while the stacking modes near anti-phase boundary (APB) and twin boundary (TB) were tessellations of two differently oriented flattened hexagonal subunits. The transition region at twin domain junctions has hybrid structure and perfect or imperfect pentagram structure. Centered with the perfect pentagram transition structure, a rotation twin with ten fan-shaped domains and constituted by five twin variants can be deduced. (C) 2013 Elsevier B. V. All rights reserved.