Small interfering RNA (siRNA) therapeutic is considered to be a promising modality for the treatment of hyperlipidemia. Establishment of a thermostable clinically applicable delivery system remains a most challenging issue for siRNA drug development. Here, a series of ionizable lipid-like materials were rationally designed; 4 panels of lipid formulations were fabricated and evaluated on the basis of four representative structures. The lead lipid (A1-D1-5) was stable at 40°C, and the optimized formulation (iLAND) showed dose and time dual-dependent gene silencing pattern with median effective dose of 0.18 mg/kg. In addition, potent and durable reduction of serum cholesterol and triglyceride were achieved by administering siRNAs targeting angiopoietin-like 3 or apolipoprotein C3 ( APOC3 ) in high-fat diet–fed mice, db/db mice, and human APOC3 transgenic mice, respectively, accompanied by displaying ideal safety profiles. Therefore, siRNA@iLAND prepared with thermostable A1-D1-5 demonstrates substantial value for siRNA delivery, hyperlipidemia therapy, and prevention of subsequent metabolic diseases.

China's Mars probe, named Tianwen-1, including an orbiter and a landing rover, will be launched during the July-August 2020 Mars launch windows. Selected to be among the rover payloads is a Subsurface Penetrating Radar module (RoSPR). The main scientific objective of the RoSPR is to characterize the thickness and sub-layer distribution of the Martian soil. The RoSPR consists of two channels. The low frequency channel of the RoSPR will penetrate the Martian soil to depths of 10 to 100 m with a resolution of a few meters. The higher frequency channel will penetrate to a depth of 3 to 10 m with a resolution of a few centimeters. This paper describes the design of the instrument and some results of field experiments.

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Heterostructure nanoparticles (NPs), constructed by two single‐component NPs with distinct nature and multifunctional properties, have attracted intensive interest in the past few years. Among them, heterostructures made of upconversion NPs (UCNPs) and metal–organic frameworks (MOFs) can not only integrate the advantageous characteristics (e.g., porosity, structural regularity) of MOFs with unique upconverted optical features of UCNPs, but also induce cooperative properties not observed either for single component due to their special optical or electronic communications. Recently, diverse UCNP‐MOF heterostructures are designed and synthesized via different strategies and have demonstrated appealing potential for applications in biosensing and imaging, drug delivery, and photodynamic therapy (PDT). In this review, the synthesis strategies of UCNP‐MOF heterostructures are first summarized, then the authors focus mainly on discussion of their biomedical applications, particularly as PDT agents for cancer treatment. Finally, the authors briefly outlook the current challenges and future perspectives of UCNP‐MOF hybrid nanocomposites. The authors believe that this review will provide comprehensive understanding and inspirations toward recent advances of UCNP‐MOF heterostructures.

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An experimental study on ignition and combustion of single particles was conducted at normal gravity (1-g) and microgravity (l-g) for three high volatile coals with initial diameter of 1.5 and 2.0 mm, respectively. The non-intrusive twin-color pyrometry method was used to retrieve the surface temperature of the coal particle through processing the images taken by a color CCD camera. At the same time, a mathematical model considering thermal conduction inside the coal particle was developed to simulate the ignition process.Both experiments and modeling found that ignition occurred homogeneously at the beginning and then heterogeneously for the testing coal particles burning at l-g. Experimental results confirmed that ignition temperature decreased with increasing volatile content and increasing particle size. However, contradicted to previous studies, this study found that for a given coal with certain particle size, ignition temperature was about 50-80 K lower at l-g than that at 1-g.The model predictions agreed well with the l-g experimental data on ignition temperature. The criterion that the temperature gradient in the space away from the particle surface equaled to zero was validated to determine the commence of homogeneous ignition. Thermal conduction inside the particle could have a noticeable effect for determining the ignition temperature. With the consideration of thermal conduction, the critical size for the phase transient from homogeneous to heterogeneous is about 700 lm at ambient temperature 1500 K and oxygen concentration 0.23.

Unmanned aerial vehicles (UAVs)-based environmental studies are gaining space in recent years due to their advantages of minimal cost, flexibility, and very high spatial resolution. Researchers can acquire imagery according to their schedule and convenience with the option of alternating the sensors working in visible, infrared, and microwave wavelengths. The recent developments in UAVs and in the associated image-processing techniques extend the fields of UAVs application. Inherent geometric deformation of UAVs images inevitably leads to burgeoning interest in exploring the geographical registration techniques of UAVs images preprocessing. However, atmospheric correction had been generally neglected due to the low altitudes of UAVs platforms. The path radiance of low-latitude atmosphere misleads the reflectance of target objects. Thus, a valid atmospheric correction is essential in the cases where vegetation indices (VIs) are adopted in vegetation monitoring. The off-the-shelf atmospheric correction algorithms adopted in satellite-based remote sensing are typically ill-suited for UAVs-based images due to the distinctly different altitudes and radiation transfer modes. This article identified the effect of atmospheric attenuation for spectral data collected by UAVs sensors of different altitudes and developed a physical-based atmospheric correction algorithm of UAVs images. Field-measured reflectance spectrum was essential in modelling. A sunny and dry day and a flat terrain were the two prerequisites to ensure the general application of the developed algorithm. A case study was subsequently carried out to verify the utility of the developed algorithm, and the results showed that VIs based on the UAVs images of different altitudes had a similar ability in vegetation assessment as groundbased recordings. However, the assessment accuracy could be clearly improved by using the developed atmospheric correction algorithm. ARTICLE HISTORY

Tumor‐specific miRNA imaging is achieved through the integration of enzyme‐triggered catalytic hairpin assembly with lipid‐nanoparticle‐based delivery. The approach enables controlled activation of signal amplification in cancer cells with improved imaging contrast, as reported by Lele Li, Mengyuan Li, and co‐workers in their Research Article (e202214230).