The development of high-performance ultraelastic metals with superb strength, a large elastic strain limit and temperature-insensitive elastic modulus (Elinvar effect) are important for various ...industrial applications, from actuators and medical devices to high-precision instruments
. The elastic strain limit of bulk crystalline metals is usually less than 1 per cent, owing to dislocation easy gliding. Shape memory alloys
-including gum metals
and strain glass alloys
-may attain an elastic strain limit up to several per cent, although this is the result of pseudo-elasticity and is accompanied by large energy dissipation
. Recently, chemically complex alloys, such as 'high-entropy' alloys
, have attracted tremendous research interest owing to their promising properties
. In this work we report on a chemically complex alloy with a large atomic size misfit usually unaffordable in conventional alloys. The alloy exhibits a high elastic strain limit (approximately 2 per cent) and a very low internal friction (less than 2 × 10
) at room temperature. More interestingly, this alloy exhibits an extraordinary Elinvar effect, maintaining near-constant elastic modulus between room temperature and 627 degrees Celsius (900 kelvin), which is, to our knowledge, unmatched by the existing alloys hitherto reported.
MicroRNAs are critical regulators of cancer initiation, progression, and dissemination. Extensive evidence suggests that the inhibition of over-expressed oncogenic miRNA function can be a robust ...strategy for anticancer therapy. However, in vivo targeted delivery of miRNA therapeutics to various types of cancers remains a major challenge. Inspired by their natural synthesis and cargo delivery capabilities, researchers have exploited tumor cell-derived extracellular vesicles (TEVs) for the cancer-targeted delivery of therapeutics and theranostics. Here, we investigate a TEV-based nanoplatform for multimodal miRNA delivery and phototherapy treatments as well as the magnetic resonance imaging of cancer. We demonstrated loading of anti-miR-21 that blocks the function of endogenous oncogenic miR-21 over-expressed in cancer cells into and subsequent delivery by TEVs derived from 4T1 cells. We also produced Cy5-anti-miR-21-loaded TEVs from two other cancer cell lines (HepG2 and SKBR3) and confirmed their robust homologous and heterologous transfection efficiency and intracellular Cy5-anti-miR-21 delivery. Additionally, TEV-mediated anti-miR-21 delivery attenuated doxorubicin (DOX) resistance in breast cancer cells with a 3-fold higher cell kill efficiency than in cells treated with DOX alone. We then investigated TEVs as a biomimetic source for the functionalization of gold–iron oxide nanoparticles (GIONs) and demonstrated nanotheranostic properties of TEV-GIONs in vitro. TEV-GIONs demonstrated excellent T2 contrast in in vitro magnetic resonance (MR) imaging and resulted in efficient photothermal effect in 4T1 cells. We also evaluated the biodistribution and theranostic property of anti-miR-21 loaded TEV-GIONs in vivo by labeling with indocyanine green near-infrared dye. We further validated the tumor specific accumulation of TEV-GIONs using MR imaging. Our findings demonstrate that the distribution pattern of the TEV-anti-miR-21-GIONs correlated well with the tumor-targeting capability as well as the activity and efficacy obtained in response to doxorubicin combination treatments. TEVs and TEV-GIONs are promising nanotheranostics for future applications in cancer molecular imaging and therapy.
A new method, combining empirical modeling with time series Interferometric Synthetic Aperture Radar (InSAR) data, is proposed to provide an assessment of potential landslide volume and area. The ...method was developed to evaluate potential landslides in the Heitai river terrace of the Yellow River in central Gansu Province, China. The elevated terrace has a substantial loess cover and along the terrace edges many landslides have been triggered by gradually rising groundwater levels following continuous irrigation since 1968. These landslides can have significant impact on communities, affecting lives and livelihoods. Developing effective landslide risk management requires better understanding of potential landslide magnitude. Fifty mapped landslides were used to construct an empirical power-law relationship linking landslide area (AL) to volume (VL) (VL = 0.333 × AL1.399). InSAR-derived ground displacement ranges from −64 mm/y to 24 mm/y along line of sight (LOS). Further interpretation of patterns based on remote sensing (InSAR & optical image) and field survey enabled the identification of an additional 54 potential landslides (1.9 × 102 m2 ≤ AL ≤ 8.1 × 104 m2). In turn this enabled construction of a map that shows the magnitude of potential landslide activity. This research provides significant further scientific insights to inform landslide hazard and risk management, in a context of ongoing landscape evolution. It also provides further evidence that this methodology can be used to quantify the magnitude of potential landslides and thus contribute essential information towards landslide risk management.
•A new approach combining time-series InSAR with empirical model is proposed.•The volume and area of potential landslides are forecasted.•The approach is validated for recent landslides.•The approach contributes essential information to landslide risk assessment.
Clouds cover about 70% of Earth's surface and play a dominant role in the energy and water cycle of our planet. Only satellite observations provide a continuous survey of the state of the atmosphere ...over the entire globe and across the wide range of spatial and temporal scales that compose weather and climate variability. Satellite cloud data records now exceed more than 25 years; however, climate data records must be compiled from different satellite datasets and can exhibit systematic biases. Questions therefore arise as to the accuracy and limitations of the various sensors and retrieval methods. The Global Energy and Water Cycle Experiment (GEWEX) Cloud Assessment, initiated in 2005 by the GEWEX Radiation Panel (GEWEX Data and Assessment Panel since 2011), provides the first coordinated intercomparison of publicly available, standard global cloud products (gridded monthly statistics) retrieved from measurements of multispectral imagers (some with multiangle view and polarization capabilities), IR sounders, and lidar. Cloud properties under study include cloud amount, cloud height (in terms of pressure, temperature, or altitude), cloud thermodynamic phase, and cloud radiative and bulk microphysical properties (optical depth or emissivity, effective particle radius, and water path). Differences in average cloud properties, especially in the amount of high-level clouds, are mostly explained by the inherent instrument measurement capability for detecting and/or identifying optically thin cirrus, especially when overlying low-level clouds. The study of long-term variations with these datasets requires consideration of many factors. The monthly gridded database presented here facilitates further assessments, climate studies, and the evaluation of climate models.
The CDEX-1 experiment conducted a search of low-mass (< 10GeV/c super(2)) weakly interacting massive particles dark matter at the China Jinping Underground Laboratory using a p-type point-contact ...germanium detector with a fiducial mass of 915 g at a physics analysis threshold of 475 eVee. We report the hardware setup, detector characterization, data acquisition, and analysis procedures of this experiment. No excess of unidentified events is observed after the subtraction of the known background. Using 335.6 kg-days of data, exclusion constraints on the weakly interacting massive particle-nucleon spin-independent and spin-dependent couplings are derived.
Abstract
Nickel-based complex oxides have served as a playground for decades in the quest for a copper-oxide analog of the high-temperature superconductivity. They may provide clues towards ...understanding the mechanism and an alternative route for high-temperature superconductors. The recent discovery of superconductivity in the infinite-layer nickelate thin films has fulfilled this pursuit. However, material synthesis remains challenging, direct demonstration of perfect diamagnetism is still missing, and understanding of the role of the interface and bulk to the superconducting properties is still lacking. Here, we show high-quality Nd
0.8
Sr
0.2
NiO
2
thin films with different thicknesses and demonstrate the interface and strain effects on the electrical, magnetic and optical properties. Perfect diamagnetism is achieved, confirming the occurrence of superconductivity in the films. Unlike the thick films in which the normal-state Hall-coefficient changes signs as the temperature decreases, the Hall-coefficient of films thinner than 5.5 nm remains negative, suggesting a thickness-driven band structure modification. Moreover, X-ray absorption spectroscopy reveals the Ni-O hybridization nature in doped infinite-layer nickelates, and the hybridization is enhanced as the thickness decreases. Consistent with band structure calculations on the nickelate/SrTiO
3
heterostructure, the interface and strain effect induce a dominating electron-like band in the ultrathin film, thus causing the sign-change of the Hall-coefficient.
Improvac has been tentatively used to immune-castrate roosters. The aim of this study was to investigate whether Improvac affected skeletal muscle development in chickens. The muscle fiber type and ...size and the expression levels of genes related to muscle development in pectoral and thigh muscles were examined at 5, 9, and 14 wk of age in the control, early, late, and early + late Improvac-treated groups. Immunocastration with Improvac affected the development of thigh muscles and the expression of MYH1B, MSTN, and SM. The cross-sectional area in the early group was significantly larger than in the control group at the 14th week (P < 0.01). At the fifth week, the expression levels of MYH1B, MYOD, and MSTN in the early group were significantly higher than those in the control group (P < 0.05), and at the ninth week, the expression level of SM1 in the control group was significantly lower than that in early and late groups (P < 0.05). Immunocastration did not affect pectoral muscle development or the expression of genes related to muscle development.
Direct evidence of zonal flow (ZF) predator-prey oscillations and the synergistic roles of ZF- and equilibrium E×B flow shear in triggering the low- to high-confinement (L- to H-mode) transition in ...the DIII-D tokamak is presented. Periodic turbulence suppression is first observed in a narrow layer at and just inside the separatrix when the shearing rate transiently exceeds the turbulence decorrelation rate. The final transition to H mode with sustained turbulence and transport reduction is controlled by equilibrium E×B shear due to the increasing ion pressure gradient.
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