A biodegradable two‐dimensional (2D) delivery platform based on loading black phosphorus nanosheets (BPs) with Cas9 ribonucleoprotein engineered with three nuclear localization signals (NLSs) at C ...terminus (Cas9N3) is successfully established. The Cas9N3‐BPs enter cells effectively via membrane penetration and endocytosis pathways, followed by a BPs biodegradation‐associated endosomal escape and cytosolic releases of the loaded Cas9N3 complexes. The Cas9N3‐BPs thus provide efficient genome editing and gene silencing in vitro and in vivo at a relatively low dose as compared with other nanoparticle‐based delivery platforms. This biodegradable 2D delivery platform offers a versatile cytosolic delivery approach for CRISPR/Cas9 ribonucleoprotein and other bioactive macromolecules for biomedical applications.
Cas9 in black: A biodegradable two‐dimensional delivery platform for CRISPR/Cas9 is successfully established. It is based on loading black phosphorus nanosheets with engineered Cas9 ribonucleoprotein, enabling controlled cytosolic release and genome editing with high efficiency.
Lithium-ion (Li-ion) batteries have been widely applied in industrial applications. It is desired to predict the health state of batteries to achieve optimal operation and health management. However, ...accuracy is the biggest bottleneck for battery health prediction. In this paper, a new hybrid ensemble data-driven method is proposed to accurately predict the state-of-health (SOH) and remaining-useful-life (RUL) of Li-ion batteries. A health indicator is selected as feature inputs to predict the degradation trend of battery, after the Pearson correlation analysis. Two random learning algorithms are integrated to extract the inherent relationship between the extracted health indicator and practical SOH due to their good learning performance. Based on the estimated SOH, the nonlinear autoregressive (NAR) structure is designed to reduce the RUL prediction error of each learning model since the NAR structure makes good use of historical and current information. Finally, in order to quantitatively evaluate the prediction interval of the RUL, a Bootstrap-based uncertainty management method is designed. Test results on two publicly available datasets show that the proposed hybrid data-driven method can accurately predict the SOH and RUL of batteries. The proposed method does not require any other additional hardware or system downtime, which makes it suitable for online practical applications, such as energy storage systems and electric vehicles.
As a new kind of 2D material, black phosphorus has gained increased attention in the past three years. Although few‐layered black phosphorus nanosheets (BPs) degrade quickly under ambient conditions ...to phosphate anions, which greatly hampers their optical and electronic applications, this property also makes BPs highly biocompatible and biodegradable, and is regarded as an advantage for various biomedical applications. This Concept summarizes the state‐of‐art progresses of BPs, from fabrication and surface modification to biomedical applications. It is expected that BPs with such fascinating properties will encourage more scientists to engage in expanding its biomedical applications by tackling the scientific challenges involved in their development.
Black phosphorus is gaining increasing attention as a new 2D layered material. This Concept summarizes the state‐of‐art progress of few‐layered black phosphorus, from fabrication and surface modification to biomedical applications. Future research paths for the customization of degradation of few‐layer black phosphorus, for potential applications in the biomedical field, are also suggested.
We carry out a systematical study of the spectral lag properties of 50 single-pulsed gamma-ray bursts (GRBs) detected by the Fermi Gamma-Ray Burst Monitor. By dividing the light curves into multiple ...consecutive energy channels, we provide a new measurement of the spectral lag that is independent of energy channel selections. We perform a detailed statistical study of our new measurements. We find two similar power-law energy dependencies of both the pulse arrival time and pulse width. Our new results on the power-law indices would favor the relativistic geometric effects for the origin of spectral lag. However, a complete theoretical framework that can fully account for the diverse energy dependencies of both arrival time and pulse width revealed in this work is still lacking. We also study the spectral evolution behaviors of the GRB pulses. We find that a GRB pulse with negligible spectral lag would usually have a shorter pulse duration and would appear to have a "hardness-intensity tracking" behavior, and a GRB pulse with a significant spectral lag would usually have a longer pulse duration and would appear to have a "hard-to-soft" behavior.
Black phosphorus nanosheets (BPs) are demonstrated to be highly bioactive anti‐cancer agents because of their inherent and selective chemotherapeutic effects. Fast intracellular biodegradation of BPs ...and acute elevation of phosphate anions were observed from different types of cancer cells due to the stronger intracellular oxidative stress and accelerated energy metabolism, but normal cells are not affected. Selective biodegradation of BPs induced G2/M phase arrest and subsequent apoptosis‐ and autophagy‐mediated cell death in cancer cells but not normal cells. The selectivity was superior to that of the traditional chemotherapeutic agent, doxorubicin (DOX). In vivo assessment confirmed the efficiency of BPs in suppressing tumor growth. This study provides insights into nanostructured bioactive anti‐cancer agents and reveals a new direction for nanomedicine research.
Selective chemotherapy: Black phosphorus nanosheets constitute a new type of bioactive anti‐cancer agent. They selectively induce proliferation inhibition, G2/M arrest and apoptotic/autophagic cell death in cancer cells during natural degradation.
Although polymerase chain reaction (PCR) is the most widely used method for DNA amplification, the requirement of thermocycling limits its non-laboratory applications. Isothermal DNA amplification ...techniques are hence valuable for on-site diagnostic applications in place of traditional PCR. Here we describe a true isothermal approach for amplifying and detecting double-stranded DNA based on a CRISPR-Cas9-triggered nicking endonuclease-mediated Strand Displacement Amplification method (namely CRISDA). CRISDA takes advantage of the high sensitivity/specificity and unique conformational rearrangements of CRISPR effectors in recognizing the target DNA. In combination with a peptide nucleic acid (PNA) invasion-mediated endpoint measurement, the method exhibits attomolar sensitivity and single-nucleotide specificity in detection of various DNA targets under a complex sample background. Additionally, by integrating the technique with a Cas9-mediated target enrichment approach, CRISDA exhibits sub-attomolar sensitivity. In summary, CRISDA is a powerful isothermal tool for ultrasensitive and specific detection of nucleic acids in point-of-care diagnostics and field analyses.
Building models to predict ecosystem responses to future rainfall changes requires closely matching model complexity to data availability. A new study by Paschalis et al. (Global Change Biology, ...2020) examines opportunities to improve both data availability and model structure in 10 state‐of‐the‐art terrestrial biosphere models.
This is a Commentary on Paschalis et al. 26, 3336–3355
Although the maximized dispersion of metal atoms has been realized in the single‐atom catalysts, further improving the intrinsic activity of the catalysts is of vital importance. Here, the decoration ...of isolated Ru atoms into an edge‐rich carbon matrix is reported for the electrocatalytic hydrogen evolution reaction. The developed catalyst displays high catalytic performance with low overpotentials of 63 and 102 mV for achieving the current densities of 10 and 50 mA cm−2, respectively. Its mass activity is about 9.6 times higher than that of the commercial Pt/C‐20% catalyst at an overpotential of 100 mV. Experimental results and density functional theory calculations suggest that the edges in the carbon matrix enhance the local electric field at the Ru site and accelerate the reaction kinetics for the hydrogen evolution. The present work may provide insights into electrocatalytic behavior and guide the design of advanced electrocatalysts.
Isolated Ru atoms are decorated on an edge‐rich carbon matrix and applied as an efficient electrocatalyst for the hydrogen evolution reaction. This work demonstrates that the edges in a carbon matrix enable the integration of efficient charge delivery and a strong local electric field effect, which may shed light on the future design of efficient electrocatalysts.
A dual temperature‐ and light‐responsive C2H2/C2H4 separation switch in a diarylethene metal–organic framework (MOF) is presented. At 195 K and 100 kPa this MOF shows ultrahigh C2H2/C2H4 selectivity ...of 47.1, which is almost 21.4 times larger than the corresponding value of 2.2 at 293 K and 100 kPa, or 15.7 times larger than the value of 3.0 for the material under UV at 195 K and 100 kPa. The origin of this unique control in C2H2/C2H4 selectivity, as unveiled by density functional calculations, is due to a guest discriminatory gate‐opening effect from the diarylethene unit.
Photochromic diarylethene units were used to identify C2H2, leading to ultrahigh C2H2/C2H4 selectivity and promising application in C2H2/C2H4 separation at low temperature. The photochromic material can be further used as a temperature‐ and light‐responsive switch for C2H2/C2H4 separation.
Although phosphorene has attracted much attention in electronics and optoelectronics as a new type of two‐dimensional material, in‐depth investigations and applications have been limited by the ...current synthesis techniques. Herein, a basic N‐methyl‐2‐pyrrolidone (NMP) liquid exfoliation method is described to produce phosphorene with excellent water stability, controllable size and layer number, as well as in high yield. Phosphorene samples composed of one to four layers exhibit layer‐dependent Raman scattering characteristics thus providing a fast and efficient means for the in situ determination of the thickness (layer number) of phosphorene. The linear and nonlinear ultrafast absorption behavior of the as‐exfoliated phosphorene is investigated systematically by UV–vis–NIR absorption and Z‐scan measurements. By taking advantage of their unique nonlinear absorption, ultrashort pulse generation applicable to optical saturable absorbers is demonstrated. In addition to a unique fabrication technique, our work also reveals the large potential of phosphorene in ultrafast photonics.
A basic N‐methyl‐2‐pyrrolidone liquid exfoliation method is described to produce phosphorene with an excellent water stability, controllable size and layer number, as well as in a high yield. Phosphorene with one to four layers exhibits layer‐dependent Raman scattering characteristics thus providing a fast and efficient means for the in situ determination of the thickness of phosphorene.
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