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Polarimetry synthetic aperture radar (SAR) interferometry (PolInSAR) has been well-established for forest height estimation. However, employing mono-frequency SAR data for PolInSAR tree height inversion presents inherent limitations, posing challenges to ensure inversion accuracy. This article presents a novel method for the inversion of vegetation parameters using dual-frequency (DF) four-stage PolInSAR, aiming to address the limitations observed in mono-frequency inversion. By leveraging the differential penetration of vegetation across distinct frequency bands, this method facilitates the derivation of more precise volume-only coherence and ground phase information. Applying the DF four-stage PolInSAR method to a substantial dataset of simulation results identifies the optimal band combination as P- and L-band. Moreover, the band combination that yields the most significant enhancement in accuracy is determined to be L- and S-band. These simulation results inform the design of the DF full-polarization SAR system. Subsequently, airborne SAR data are acquired using this L- and S-band full-polarization airborne SAR system over the Saihanba Forest Farm in Hebei, China. Ground-based LiDAR measurements serve as reference values for the comparison of PolInSAR inversion results. The DF four-stage PolInSAR method has a 5.46% improvement in the inversion accuracy of airborne SAR data. Both simulation and airborne SAR data inversion outcomes demonstrate a significant enhancement in forest height inversion accuracy achieved through the DF four-stage PolInSAR method compared to the mono-frequency approach.

The welding kinetics of interface evolution and mechanism inIN718 alloy solid-state welding are investigated systematically by comparing the hot compression behavior of the separated samples and conventional samples in the temperature range of 1000 °C–1160 °C and strain rate range of 0.1/s to 5/s. The separated samples obtain higher peak stress than conventional samples, and the kinetics analysis results show that separated samples provide higher structural factors and deformation activation energy. The activation energy of the interfacial microstructure evolution of the IN718 alloy was calculated to be 29.7948 kJ/mol. The evolution mechanism of the interface microstructure is characterized by the elimination of the interface second phase and the migration of straight interfacial grain boundaries (IGBs), which is inseparable from the occurrence of interfacial dynamic recrystallization. Interfacial dynamical recrystallization helps to regulate the chemical potential around the second phase for a continuous dissociation. The migration mechanism of the IGBs is influenced by the strain rates, which is continuous dynamic recrystallization (CDRX) for high strain rates and discontinuous dynamic recrystallization (DDRX) for low strain rates.

Supercomputing technology has been supporting the solution of cutting-edge scientific and complex engineering problems since its inception—serving as a comprehensive representation of the most advanced computer hardware and software technologies over a period of time. Over the course of nearly 80 years of development, supercomputing has progressed from being oriented towards computationally intensive tasks, to being oriented towards a hybrid of computationally and data-intensive tasks. Driven by the continuous development of high performance data analytics (HPDA) applications—such as big data, deep learning, and other intelligent tasks—supercomputing storage systems are facing challenges such as a sudden increase in data volume for computational processing tasks, increased and diversified computing power of supercomputing systems, and higher reliability and availability requirements. Based on this, data-intensive supercomputing, which is deeply integrated with data centers and smart computing centers, aims to solve the problems of complex data type optimization, mixed-load optimization, multi-protocol support, and interoperability on the storage system—thereby becoming the main protagonist of research and development today and for some time in the future. This paper first introduces key concepts in HPDA and data-intensive computing, and then illustrates the extent to which existing platforms support data-intensive applications by analyzing the most representative supercomputing platforms today (Fugaku, Summit, Sunway TaihuLight, and Tianhe 2A). This is followed by an illustration of the actual demand for data-intensive applications in today’s mainstream scientific and industrial communities from the perspectives of both scientific and commercial applications. Next, we provide an outlook on future trends and potential challenges data-intensive supercomputing is facing. In a word, this paper provides researchers and practitioners with a quick overview of the key concepts and developments in supercomputing, and captures the current and future data-intensive supercomputing research hotspots and key issues that need to be addressed.

All living organisms depend on tightly regulated cellular networks to control biological functions. Proteolysis is an important irreversible post-translational modification that regulates most, if not all, cellular processes. Proteases are a large family of enzymes that perform hydrolysis of protein substrates, leading to protein activation or degradation. The 473 known and 90 putative human proteases are divided into 5 main mechanistic groups: metalloproteases, serine proteases, cysteine proteases, threonine proteases, and aspartic acid proteases. Proteases are fundamental to all biological systems, and when dysregulated they profoundly influence disease progression. Inhibiting proteases has led to effective therapies for viral infections, cardiovascular disorders, and blood coagulation just to name a few. Between 5 and 10% of all pharmaceutical targets are proteases, despite limited knowledge about their biological roles. More than 50% of all human proteases have no known substrates. We present here a comprehensive list of all current known human proteases. We also present current and novel biochemical tools to characterize protease functions in vitro, in vivo, and ex vivo. These tools make it achievable to define both beneficial and detrimental activities of proteases in health and disease.

Symbiosis receptor-like kinase (SymRK) is a key protein mediating the legume-Rhizobiumsymbiosis. Our previous work has identified an MAP kinase kinase, SIP2, as a SymRK-interacting protein to positively regulate nodule organogenesis in Lotus japonicus, suggesting that an MAPK cascade might be involved in Rhizobium-legume symbiosis. In this study, LjMPK6 was identified as a phosphorylation target of SIP2. Stable transgenic L. japonicuswith RNAi silencing of LjMPK6decreased the numbers of nodule primordia (NP) and nodule, while plants overexpressing LjMPK6increased the numbers of nodule, infection threads (ITs), and NP, indicating that LjMPK6 plays a positive role in nodulation. LjMPK6 could interact with a cytokinin receptor, LHK1 both in vivoand in vitro. LjMPK6 was shown to compete with LHP1 to bind to the receiver domain (RD) of LHK1and to downregulate the expression of two LjACS(1-aminocyclopropane-1-carboxylic acid synthase) genes and ethylene levels during nodulation. This study demonstrated an important role of LjMPK6 in regulation of nodule organogenesis and ethylene production in L. japonicus.

A series of alkaline earth metal-doped M/ZrO2catalysts (M = Mg, Ca, Sr, and Ba) were prepared by co-precipitation method. The influence of alkaline earth metal on the physicochemical properties and catalytic performance of M/ZrO2catalysts in the conversion of ethanol was investigated. The catalysts were characterized by N2adsorption/desorption method, temperature programmed desorption and X-ray diffraction. It was revealed that the introduction of alkaline earth metal changed the acidity/basicity of catalysts and positively enhanced catalytic performance in the ethanol conversion to olefins reaction. The ethylene yield increased with the introduction of alkaline earth metals, which was attributed to higher amount of strong acid sites. The maximum yield of ethylene and propylene reached 80.8% over Sr(1)/ZrO2catalyst. The adsorption of ethanol on perfect-ZrO2(101) and Sr/ZrO2(101) surfaces was investigated with density functional theory. The adsorption for ethanol on Sr/ZrO2(101) surface was more stable than on perfect-ZrO2(101). The ethanol molecule has stronger interaction with Sr/ZrO2(101) surface than perfect-ZrO2(101) surface.

Xiao-Ai-Ping (XAP), a traditional oriental medicinal herb isolated from the stem of Marsdenia tenacissima (Roxb.) Wight et Arn., has been shown to induce tumor cell apoptosis. In this study, we used confocal fluorescence microscopy and fluorescence resonance energy transfer (FRET) techniques to study the molecular mechanism of XAP-induced apoptosis in single living human lung adenocarcinoma (ASTC-a-1) cells. The efficacious apoptosis was observed at 6 h after of 100 μl XAP treatment. Further monitoring the dynamics of caspase-3 activation using FRET imaging in single living ASTC-a-1 cell expressing stably with SCAT3, a FRET probe, showed that XAP activated the caspase-3 at about 2 h after XAP treatment. These data suggest that caspase-3 activation was involved in the XAP-induced apoptosis in ASTC-a-1 cells.