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Photodynamic therapy is an emerging tumor therapy that kills tumor cells by activating reactive oxygen species (ROS) produced by photosensitizers. Mitochondria, as an important organelle, are the main generator of cellular ROS. Therefore, the development of photosensitizers capable of targeting mitochondria could significantly enhance the efficacy of photodynamic therapy. In this study, two novel ruthenium(II) complexes, Ru-1 and Ru-2, were designed and synthesized, both of which were functionalized with α,β-unsaturated ketones for sensing of glutathione (GSH). The crystal structures of the two complexes were determined and they exhibited good recognition of GSH by off–on luminescence signals. The complex Ru-2 containing aromatic naphthalene can enter the cells and react with GSH to generate a strong luminescence signal that can be used to monitor intracellular GSH levels through imaging. Ru-2 also has an excellent mitochondrial localization ability with a Pearson's coefficient of 0.95, which demonstrates that it can efficiently target the mitochondria of tumor cells to enhance the effectiveness of photodynamic therapy as a photosensitizer. [ABSTRACT FROM AUTHOR]

Beneath Enceladus' ice crust lies an ocean which might host habitable conditions. Here, the scale and productivity of a notional Enceladean methanogenic biosphere are computed as a function of the core‐to‐ocean flux of hydrogen and the ratio between abiotic and biotic methane in Enceladus' space plume. Habitats with an ocean‐top pH range of 8–9 have up to 40%–60% probability of being energy‐limited. Those at pH > 9 are increasingly uninhabitable, and those <8.5 are increasingly likely to host exponential growth, possibly leading to compositional inconsistencies between the ocean and Cassini gas observations. In those cases, energy‐based habitability models cannot infer an inhabited Enceladus consistent with both Earth life and Cassini measurements without including additional microbial growth limiters such as nutrient limitation, toxicity, or spatial constraints. If methanogens are isolated to a 350 K seafloor habitat and consume 10 mol s−1 of H2, the most probable biomass is 103, 103.7 kg C with ocean‐top pH 8,9, respectively. Biomass production consistent with space plume fluxes is 104–106 kgC yr−1—milligrams of cellular carbon per kilogram of H2O ejected—but requires that >50% of the space plume methane is biotic. Alternative scenarios are presented, and biomass is generally lower when habitat temperature is higher. Ocean biomass density cannot yet be reliably estimated owing to uncertainties in the scale and physicochemical properties of Enceladus' putative habitats. Evaluating abiotic to biotic ratios in plume methane and organic material could help identify false negative results from life detection missions and constrain the scale of an underlying biosphere. Plain Language Summary: The Cassini spacecraft observed energy and nutrient sources for life erupting from a water ocean below the icy exterior of Saturn's moon Enceladus. Future spacecraft planned for Enceladus, Europa and Titan will obtain similar measurements in greater detail. In this work, we calculate the probability that different suites of environments inside Enceladus' ocean are habitable for methanogens, an ancient type of organism which may be able to survive there. Three scenarios are possible: uninhabitable, habitable, and energy‐saturated. Next, we extend this calculation to show that the possible biosphere is small but productive. Microbial waste, generated at the seafloor, could be ejected from the ocean and consequently snow down onto Enceladus' surface. Mass spectrometers on future spacecraft could constrain these possibilities further and may be critical to inferring biosignatures when cell densities are too low to detect. Key Points: Spatial habitability on Enceladus is not guaranteed, and additional modeling parameters are needed to evaluate possible vacant habitatsCell turnover is important for life detection missions and can be constrained more tightly than total biomassAbiotic to biotic ratios of space plume carbon are critical as biosignatures and for assessing the scale of Enceladus' notional biosphere [ABSTRACT FROM AUTHOR]

Laser‐driven phosphor‐converted white‐laser diodes are supposed to be next‐generation high‐brightness lighting sources for their unparalleled photoelectric efficiency and light quality, yet a significant obstacle hitherto has resided in the shortage and serious laser‐induced luminescence saturation of red emitters. Here, a hot‐pressing synthesis route to obtain high‐performance red‐emitting cordierite (Mg2Al4Si5O18:Eu2+) ceramic is developed, which enables the in situ formation of bulk specimens with high crystallinity (>90%) from the counterpart glass powders. A preeminent saturation threshold of 21 W mm−2 is realized in a red‐emitting Mg2Al4Si5O18:Eu2+ ceramic film converter. More importantly, the luminous exitance reaches 209 lm mm−2, which is 5 times that of commercial red phosphor‐converted‐LED, indicating breakthrough progress in the comprehensive light‐emitting performance of red converters. This work innovates the solid‐state synthesis of laser bulk converters from glass to meet the demanding requirements of advanced warm white laser lighting. [ABSTRACT FROM AUTHOR]

Near‐infrared (NIR) phosphor‐converted light‐emitting diodes (pc‐LEDs) lighting sources are applied in non‐destructive examination and illumination supplements for night monitoring. As a critical component of NIR pc‐LED, NIR phosphors are required to possess a high external quantum efficiency (EQE), super thermal stability, and broadband emission to meet applications. Here, Na2SrGe6O14:Cr3+ (NSGO:Cr) glass ceramics (GC) bulk via highly crystallization from glass precursor is fabricated and demonstrates an ultrabroad emission band centered at 815 nm with a full width at half‐maximum (FWHM) of 214 nm and a high EQE of 49.2%. Moreover, Yb3+ co‐doping significantly enhances Cr3+ → Yb3+ energy transfer (ET) due to the stronger Yb3+: 2F7/2‐2F5/2 absorption. Benefiting from the ET process, the Cr/Yb co‐doped GC exhibits NIR‐I/II emission with improved thermal stability from 30.1% to 65.0%. Furthermore, an encapsulant‐free NIR GC‐converted LED (GCc‐LED) is prepared and exhibits 52.2 mW NIR output power with a high photoelectric conversion efficiency (PCE) of 19.4%. Under a large current of 600 mA, the NIR device exhibits a watt‐level output power of 922.4 mW with a PCE of 9.1%. Compared to conventional NIR powder phosphors, NSGO:Cr/Yb GC with high performance can open up an avenue for the fabrication of high power NIR lighting sources. [ABSTRACT FROM AUTHOR]

The interaction mechanism between grouted anchor cables and the surrounding rock mass or soil are complicated and difficult to investigate using conventional monitoring technologies. This study focuses on the in-situ pullout behavior of grouted anchor cables using Brillouin Optical Time-Domain Analysis technique. A series of pullout tests were conducted on anchor cables with five different anchor lengths and three grouting methods. Distributed fiber optic sensors were used to measure the strain distribution of cable bolts from tip to top. The in-situ pullout test results show that both ultimate pullout resistance and ultimate displacement at the ultimate pullout resistance increase with anchor length. The bond strength suffers a slight variation with an increase in anchor length. Both ultimate pullout resistance and the ultimate displacement for Type-B grouting (grouting with reaming) and Type-C grouting (secondary grouting) are larger than those for Type-A grouting (one-time grouting). The shear bond strength of Type-C grouting is greater than that of Type-A grouting. Results from Gaussian functions analysis show that it is feasible to use the function to characterize the axial stress of anchor cables. Furthermore, the overall mobilized percentage η was evaluated. The anchor cables with smaller anchor lengths will result in greater η. The η for the anchor cables of 6 m reaches 92% at the last load, whereas the anchor cables of 18 m were mobilized by only 29% at the last load. The grouting method has a negligible effect on the η, increasing from 22% to 29% in process of the pullout test. [ABSTRACT FROM AUTHOR]

From the end of May to the first ten days of June in 2020, a 12 day heavy rain process occurred in Guangxi. Due to the extreme complexity of its formation, it is necessary to analysis deeply and reveal its characteristics and causes. Based on hourly EC ERA5 0.25° x 0.25° reanalysis and real data, a multiscale comprehensive analysis of the process is carried out. The results show that:(1) This process has the characteristics of long duration of heavy rainfall, wide range, strong intensity, large accumulated rainfall, breaking the historical record of 24 h rainfall in many places and particularly serious disaster. (2) The process occurs under the circulation background of favorable configuration of mid-and-high-latitudes circulation, subtropical high, Bay of Bengal trough, low-level jet and South Asia high. There is no stable confrontation between the South Asian high transition layer and the subtropical high. there is a Transition from the meridional circulation to zonal circulation in mid-and-high-latitudes. The influence of cold air on South China is fluctuating, it causes alternating effects of cold front, stationary front and warm-sector. Thus, the local, regional and provincial rainstorms occur alternately, which is obviously different from the previous continuous rainstorms. (3) The atmosphere accumulates large energy, and huge energy is accumulated before the rainstorm in the fronts and warm-sector. Energy accumulation and effective release are positively correlated with the maximum hourly rainfall. The high temperature and humidity of the lower atmosphere and the deep wet layer of the whole atmosphere and the smaller CIN and lower TCL_P are conducive to energy accumulation and convection triggering. Warm sector and static Front Rainstorm have easier environmental conditions for triggering. The extreme convergence of energy, power and water vapor leads to the extreme rainfall. (4) The frontal rainstorm is triggered by the surface mesoscale frontal area, shear line and terrain. The combination of systems and the enhancement of low-level environmental wind field organize the development of convection. The warm-sector rainstorm is triggered by the cyclonic shear on the left side of the boundary layer jet axis, the convergence of low-level jet outlet and topographic uplift. The pulsation of jet stream enhances the development of convection. (5) The frontal rainstorm is a mobile cloud belt, and the warm sector rainstorm is a less mobile cloud cluster. The lower the cloud top brightness temperature, the greater the maximum hourly rainfall. The cloud top brightness temperature lower than 200 K can be used as the criterion for the maximum hourly rainfall greater than 50 mm/h. The maximum hourly rainfall occurs after the minimum cloud top brightness temperature reaches the minimum value. The heavy rainfall begins with the maximum radar RCS ≥ 45 dBZ and lasts for the maximum radar RCS ≥ 50 dBZ. The front echo is cold cloud echo with high centroid, and the warm-sector echo is warm cloud echo with low centroid. (6) Topography plays an important role in triggering and maintaining rainstorm, and it is more obvious for warm-sector rainstorm.(7) There are differences between the observation and reanalysis data in the penetration analysis of weak cold air, and the former is easier to capture the convective trigger. [ABSTRACT FROM AUTHOR]

LncRNAs are emerging as important regulators of gene expression by controlling transcription in the nucleus and by modulating mRNA translation in the cytoplasm. In this study, we reveal a novel function of lncRNA SNHG15 in mediating breast cancer cell invasion through regulating the local translation of CDH2 mRNA. We show that SNHG15 preferentially localizes at the cellular protrusions or cell leading edge and that this localization is directed by IMP1, a multifunctional protein involved in many aspects of RNA regulation. We demonstrate that SNHG15 also forms a complex with nucleolin, allowing nucleolin to be co-transported with SNHG15 to the cell protrusions, where the accumulated nucleolin is able to bind to CDH2 mRNA. Interaction with nucleolin stabilizes local CDH2 mRNA and regulates its translation, thus promoting cell invasive potential. Our findings reveal an underlying mechanism by which lncRNA could serve as a carrier to transport a protein regulator into a specific cell compartment to enhance target mRNA expression. [ABSTRACT FROM AUTHOR]

GSH is one of the most important reducing agents in biological systems. The depletion of GSH in the human body is linked to many diseases. Therefore, it is necessary to develop suitable and efficient probes for detecting GSH concentrations in real samples. In this work, we designed and synthesized two near-infrared emitting iridium(III) complex probes containing a novel ligand functionalized with an α,β-unsaturated ketone for the rapid and sensitive detection of GSH. The molecular structure of Ir2 was determined by X-ray crystallography. Due to their large Stokes shift, long luminescence lifetime and NIR emission, these probes were successfully applied in the imaging of GSH in living cells. In addition, two iridium(III) complexes have strong singlet oxygen generation ability which can be used for photodynamic therapy (PDT) upon visible light irradiation. On the basis of these findings, our iridium(III) complexes may serve as GSH probes for HeLa cell imaging and as photosensitizers for PDT. [ABSTRACT FROM AUTHOR]